U.S. patent application number 15/727859 was filed with the patent office on 2018-02-01 for weight material dispensing, cutting and applying system.
The applicant listed for this patent is 3M Innovative Properties Company, ESys Corporation. Invention is credited to Benjamin D. BELKNAP, Scott R. CLAXTON, Mark A. COMPTON, John K. FUNCHEON, Mark R. GABEL, Louis R. HEDTKE, JR., Matthew W. KING, David L. MCDOLE.
Application Number | 20180031438 15/727859 |
Document ID | / |
Family ID | 44971313 |
Filed Date | 2018-02-01 |
United States Patent
Application |
20180031438 |
Kind Code |
A1 |
COMPTON; Mark A. ; et
al. |
February 1, 2018 |
Weight Material Dispensing, Cutting and Applying System
Abstract
An apparatus for balancing a wheel includes a tool and an arm
control module. The tool is mechanically coupled to an arm and
includes a leading edge, a trailing edge, and a face surface that
forms an arc between the leading and trailing edges. The arm
control module actuates the arm to position the leading edge of the
tool a predetermined distance from an edge of a deck of a cutting
apparatus to receive a piece of non-segmented wheel weight
material. A blade of a cutting apparatus passes between the edge of
the deck and the leading edge of the tool to cut the piece from the
non-segmented wheel weight material.
Inventors: |
COMPTON; Mark A.; (Lake
Orion, MI) ; HEDTKE, JR.; Louis R.; (Grosse Pointe
Woods, MI) ; KING; Matthew W.; (Mt. Clemens, MI)
; CLAXTON; Scott R.; (Ortonville, MI) ; MCDOLE;
David L.; (Westfield, IN) ; FUNCHEON; John K.;
(Carmel, IN) ; GABEL; Mark R.; (Cottage Grove,
MN) ; BELKNAP; Benjamin D.; (Northville, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ESys Corporation
3M Innovative Properties Company |
Auburn Hills
St.Paul |
MI
MN |
US
US |
|
|
Family ID: |
44971313 |
Appl. No.: |
15/727859 |
Filed: |
October 9, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14564029 |
Dec 8, 2014 |
9784636 |
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15727859 |
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13175413 |
Jul 1, 2011 |
8943940 |
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14564029 |
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12683495 |
Jan 7, 2010 |
8505423 |
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13175413 |
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61428534 |
Dec 30, 2010 |
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61143284 |
Jan 8, 2009 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B26D 3/08 20130101; B26D
5/20 20130101; G01M 1/326 20130101; B26D 7/30 20130101; Y10T
83/7195 20150401; B26D 7/06 20130101; Y10T 83/023 20150401; Y10T
83/173 20150401; Y10T 83/04 20150401; B26D 1/085 20130101; B26D
7/1863 20130101; G01M 1/16 20130101 |
International
Class: |
G01M 1/16 20060101
G01M001/16; G01M 1/32 20060101 G01M001/32; B26D 7/30 20060101
B26D007/30; B26D 5/20 20060101 B26D005/20 |
Claims
1. An apparatus for balancing a wheel, the apparatus comprising: a
tool that is mechanically coupled to an arm and that includes a
leading edge, a trailing edge, and a face surface that forms an arc
between the leading and trailing edges; an arm control module that
actuates the arm to position the leading edge of the tool a
predetermined distance from an edge of a deck of a cutting
apparatus to receive a wheel weight, wherein the cutting apparatus
separates the wheel weight from a supply feed of wheel weight
material; and a sensor that detects presence or absence of the
wheel weight on the tool.
2. The apparatus of claim 1, wherein the sensor detects the
presence or absence of the wheel weight on the face surface of the
tool within a second predetermined distance of the leading edge of
the tool.
3. The apparatus of claim 1, wherein the sensor is located adjacent
to the leading edge of the tool.
4. The apparatus of claim 1, wherein the face surface of the tool
includes an aperture, and wherein the sensor is located within the
aperture.
5. The apparatus of claim 1, further comprising a second sensor
that detects presence or absence of the wheel weight on the
tool.
6. The apparatus of claim 1, wherein the arm control module
selectively performs error handling in response to the sensor
detecting that the wheel weight is absent from the tool.
7. The apparatus of claim 6, wherein the error handling includes
wiping the face surface of the tool.
8. The apparatus of claim 1, wherein, subsequent to the tool moving
away from the cutting apparatus, application of the wheel weight to
the wheel is skipped in response to the sensor indicating that the
wheel weight is absent from the tool.
9. The apparatus of claim 1, wherein, to receive the wheel weight,
the arm control module positions the leading edge of the tool
parallel to the edge of the deck and coplanar with a surface of the
deck.
10. The apparatus of claim 1, further comprising: a cutter
interfacing module that selectively outputs an in-position signal
in response to the leading edge of the tool being located at the
predetermined distance from the edge of the deck; and a cutter
actuator control module that waits to actuate the cutting apparatus
until the in-position signal is received from the cutter
interfacing module.
11. The apparatus of claim 1, wherein a blade of the cutting
apparatus passes between the edge of the deck and the leading edge
of the tool to separate the wheel weight from the supply feed of
the wheel weight material.
12. The apparatus of claim 1, further comprising at least one
magnetic device configured to attract the wheel weight to the face
surface of the tool.
13. A method for balancing a wheel, the method comprising:
positioning a leading edge of a tool a predetermined distance from
an edge of a deck to receive a wheel weight, wherein the tool
includes a trailing edge and a face surface that forms an arc
between the leading and trailing edges; bringing the wheel weight
into contact with the tool; separating the wheel weight from a
supply feed of wheel weight material; subsequent to the separating,
detecting presence or absence of the wheel weight on the tool; and
selectively moving the tool to apply the wheel weight to the
wheel.
14. The method of claim 13 wherein the wheel weight is connected to
the tool prior to separating the wheel weight from the supply feed
of wheel weight material.
15. The method of claim 13, wherein positioning the leading edge of
the tool includes actuating an arm to which the tool is connected,
and wherein moving the tool includes selectively actuating the
arm.
16. The method of claim 13, further comprising applying the wheel
weight to the wheel, wherein applying the wheel weight to the wheel
includes pressing the wheel weight against the wheel using a
rolling motion.
17. The method of claim 13, further comprising moving the tool to
apply the wheel weight to the wheel along a first plane of the
wheel beginning at the leading edge of the tool.
18. The method of claim 13, wherein the moving is skipped in
response to detecting the absence of the wheel weight on the
tool.
19. The method of claim 13, further comprising: joining a first
roll of wheel weight material with a second roll of wheel weight
material using a splice; and applying a splice indicium to the
splice to allow detection of a location of the splice.
20. The method of claim 19, further comprising, in response to
detecting the splice indicium: cutting a spliced section of wheel
weight material surrounding the location of the splice; and
discarding the spliced section of wheel weight material without
applying the spliced section of wheel weight material to the wheel.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 14/564,029 (now U.S. Pat. No. 9,784,363), filed on Dec. 8,
2014, which is a continuation of U.S. patent application Ser. No.
13/175,413 (now U.S. Pat. No. 8,943,940), filed on Jul. 1, 2011,
which is a continuation-in-part of U.S. patent application Ser. No.
12/683,495 (now U.S. Pat. No. 8,505,423), filed on Jan. 7, 2010,
which claims priority to U.S. Provisional Application No.
61/143,284, filed on Jan. 8, 2009. This application claims the
benefit of U.S. Provisional Application No. 61/428,534, filed on
Dec. 30, 2010. The entire disclosures of the above applications are
incorporated by reference herein.
FIELD
[0002] The present disclosure relates to weight material and more
particularly to weight material dispensing and cutting systems and
methods of operating such systems.
BACKGROUND
[0003] The background description provided herein is for the
purpose of generally presenting the context of the disclosure. Work
of the presently named inventors, to the extent it is described in
this background section, as well as aspects of the description that
may not otherwise qualify as prior art at the time of filing, are
neither expressly nor impliedly admitted as prior art against the
present disclosure.
[0004] Rotating assemblies are used in many applications. For
example only, in automotive applications, wheel/tire assemblies are
used to couple the vehicle to the ground. As the vehicle moves,
wheel/tire assemblies rotate many times. At higher rates of speed,
any weight imbalance in the wheel/tire assemblies may result in
vibration, which increases wear on vehicle components and may be
perceived as a poor ride by the driver.
[0005] As a result, wheel/tire assemblies are balanced in a
balancing process. A balancing machine may spin a wheel/tire
assembly to determine which points of the wheel/tire assembly
require more or less weight so that the weight will be evenly
distributed across the assembly. In most applications, it is easier
to add additional weight than to remove weight.
[0006] The balancing machine may therefore determine how much
weight to add to which locations of the wheel/tire assembly in
order to balance the weight distribution of the assembly. In
various implementations, two locations on the assembly may be
selected, although more or fewer are possible. The balancing
locations may be predetermined, and the balancing machine simply
determines how much weight to apply to each of the predetermined
balancing locations.
[0007] For a rimmed wheel, lead pound-on weights may be attached to
the rim of the wheel. For example, lead weights from 0.5 ounces to
10 ounces in increments of 0.5 ounces may be stocked by businesses
that balance wheel/tire assemblies. In this example, 20 different
part numbers of lead weights must be inventoried and managed. The
various lead weights may not look appreciably different in size,
thereby leading to inadvertent mixing of the weights and
inadvertent use of the wrong size of weight. In addition, lead
toxicity is a concern. Other materials may be used for pound-on
weights, such as iron. With iron pound-on weights, rust may be a
concern.
[0008] To address these concerns, systems of encased lead weights
have been developed. In these systems, individual weights (such as
0.5 ounce weights) are encased in a non-toxic coating, such as
plastic, and the coating connects the individual weights together
to form a segmented strip. Depending on the weight desired for
balancing, the corresponding number of weights can be cut from the
strip. The segmented strip of weights allows a single part number
to be inventoried. The segmented strip may have an adhesive backing
that secures the cut segments to the wheel/tire assembly. The
non-toxic coating may protect against lead toxicity and/or
rust.
SUMMARY
[0009] An apparatus for balancing a wheel includes a tool and an
arm control module. The tool is mechanically coupled to an arm and
includes a leading edge, a trailing edge, and a face surface that
forms an arc between the leading and trailing edges. The arm
control module actuates the arm to position the leading edge of the
tool a predetermined distance from an edge of a deck of a cutting
apparatus to receive a piece of non-segmented wheel weight
material. A blade of a cutting apparatus passes between the edge of
the deck and the leading edge of the tool to cut the piece from the
non-segmented wheel weight material.
[0010] An apparatus for balancing a wheel includes a first tool, a
second tool, an actuator, and an arm control module. The first tool
is positioned by an arm and includes a first face surface. The
second tool is positioned by the arm and includes a second face
surface. The actuator selectively extends and retracts the second
tool relative to the first tool. The arm control module, after a
first piece of non-segmented wheel weight material is deposited on
the first face surface and a second piece of the non-segmented
wheel weight material is deposited on the second face surface, (i)
applies the first piece along a first plane of the wheel by moving
the arm and (ii) applies the second piece along a second plane of
the wheel while the second tool is extended relative to the first
tool by moving the arm. The first and second planes do not
intersect.
[0011] A method of cutting non-segmented wheel weight material
includes actuating an arm to position a leading edge of a tool a
predetermined distance from an edge of a deck of a cutting
apparatus. The tool includes the leading edge, a trailing edge, and
a face surface that forms an arc between the leading and trailing
edges. The method further includes receiving a piece of the
non-segmented wheel weight material using the tool. A blade of the
cutting apparatus passes between the edge of the deck and the
leading edge of the tool to cut the piece.
[0012] A method for balancing a wheel includes selectively
extending and retracting a first tool relative to a second tool.
The first and second tools are positioned by an arm, and the first
and second tools include first and second face surfaces,
respectively. The method further includes, after a first piece of
non-segmented wheel weight material is deposited on the first face
surface and a second piece of the non-segmented wheel weight
material is deposited on the second face surface, moving the arm to
apply the first piece along a first plane of the wheel while the
first tool is extended relative to the second tool and moving the
arm to apply the second piece along a second plane of the wheel,
wherein the first and second planes do not intersect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present disclosure will become more fully understood
from the detailed description and the accompanying drawings,
wherein:
[0014] FIG. 1A is an isometric view of an example continuous weight
material dispensing and cutting system according to the principles
of the present disclosure;
[0015] FIG. 1B is a front view of an example continuous weight
material dispensing and cutting system according to the principles
of the present disclosure;
[0016] FIG. 2A is an isometric view of an example implementation of
a cutting apparatus according to the principles of the present
disclosure;
[0017] FIG. 2B is a side view of an example implementation of a
cutting apparatus according to the principles of the present
disclosure;
[0018] FIG. 2C is a top view of an example implementation of a
cutting apparatus according to the principles of the present
disclosure;
[0019] FIG. 2D is a simplified top view of an example
implementation of a cutting apparatus according to the principles
of the present disclosure;
[0020] FIG. 2E is a partial front view of an example implementation
of a cutting apparatus according to the principles of the present
disclosure;
[0021] FIGS. 2F-2H are cross-sectional views of example
implementations of a cutting apparatus along the A-A line of FIG.
2E according to the principles of the present disclosure;
[0022] FIG. 2I is a composite of end, side, and isometric views of
a drive roller depicted in FIG. 2H according to the principles of
the present disclosure;
[0023] FIG. 2J is an end view of an example implementation of a
cutting apparatus according to the principles of the present
disclosure;
[0024] FIG. 3 is a functional block diagram of an example
implementation of control electronics for the system according to
the principles of the present disclosure;
[0025] FIG. 4A is an isometric view of an example implementation of
a dispensing apparatus according to the principles of the present
disclosure;
[0026] FIG. 4B is a front view of an example implementation of a
dispensing apparatus according to the principles of the present
disclosure;
[0027] FIG. 4C is a rear view of an example implementation of a
dispensing apparatus according to the principles of the present
disclosure;
[0028] FIG. 4D is a partial rear view of an example implementation
of a dispensing apparatus according to the principles of the
present disclosure;
[0029] FIG. 5 is an isometric view of an example implementation of
a splicing apparatus according to the principles of the present
disclosure;
[0030] FIG. 6 is a block diagram of an example wheel balancing
system according to the principles of the present disclosure;
[0031] FIG. 7A is an example carside view of a wheel and tire
according to the principles of the present disclosure;
[0032] FIG. 7B is an example cross sectional view of the wheel and
the tire according to the principles of the present disclosure;
[0033] FIG. 8A and 8B are front and side views, respectively, of an
example implementation of an arm with and an end of arm tool
(EOAT), a crowder, and a conveyer system according to the
principles of the present disclosure;
[0034] FIGS. 9A-9H are various isometric views of the cutting
apparatus and a backing removal system according to the principles
of the present disclosure;
[0035] FIGS. 10A-10H are various isometric views of the cutting
apparatus, the arm, and the EOAT according to the principles of the
present disclosure;
[0036] FIGS. 11A-11G are various views of wet out tools of the EOAT
according to the principles of the present disclosure;
[0037] FIG. 12 is a flowchart depicting an example method of
balancing a wheel using the cutting apparatus, the arm, and the
EOAT according to the principles of the present disclosure;
[0038] FIG. 13 is a functional block diagram of an example control
system of the arm and the EOAT according to the principles of the
present disclosure;
[0039] FIG. 14 is an isometric view of an example implementation of
a wheel balancing system including a mounting plane learning system
according to the principles of the present disclosure; and
[0040] FIGS. 15A-15B are a two-part flowchart depicting an example
method of controlling the arm and the EOAT according to the
principles of the present disclosure.
DETAILED DESCRIPTION
[0041] The following description is merely example in nature and is
in no way intended to limit the disclosure, its application, or
uses. For purposes of clarity, the same reference numbers will be
used in the drawings to identify similar elements. As used herein,
the phrase at least one of A, B, and C should be construed to mean
a logical (A or B or C), using a non-exclusive logical or. It
should be understood that steps within a method may be executed in
different order without altering the principles of the present
disclosure.
[0042] As used herein, the term module refers to an Application
Specific Integrated Circuit (ASIC), an electronic circuit, a
processor (shared, dedicated, or group) and memory that execute one
or more software or firmware programs, a combinational logic
circuit, and/or other suitable components that provide the
described functionality.
[0043] The apparatuses and methods described herein may be
implemented by one or more computer programs executed by one or
more processors. The computer programs include processor-executable
instructions that are stored on a non-transitory tangible computer
readable medium. The computer programs may also include stored
data. Non-limiting examples of the non-transitory tangible computer
readable medium are nonvolatile memory, magnetic storage, and
optical storage.
[0044] When individual lead or iron weights are encased and joined
in a segmented strip, the granularity of control of the weight is
limited. Cutting a segment with a partial lead weight is not an
option because of the toxicity of the lead, and cutting the lead
may be more difficult than cutting the casing. Similarly, cutting a
segment with a partial iron weight exposes the iron to rust and may
be more difficult than cutting only the casing. Weight pieces are
therefore only available in increments of the individual weight.
This may limit the accuracy of the balancing. In addition, if only
half a segment in terms of weight is needed for balancing, the
entire segment is used, thereby wasting half a segment.
[0045] To overcome the problems of this segmented design, a
continuous strip of high-density weight material may be used. For
ease of storage, handling, and transportation, the weight material
may be flexible. For example, the weight material may be flexible
enough to be stored in a roll. Because the weight material is
continuous, the granularity of control of the weight of a segment
can be made arbitrarily small. Manufacturing limitations may cause
the linear density of the continuous weight material to vary
slightly over the length of the continuous weight material. The
precision of the cutting apparatus and the variance of the linear
density of the weight material therefore dictates the accuracy of
pieces cut from a continuous strip of the weight material.
[0046] In contrast to segmented strips of lead or iron weights
connected by a casing, continuous weight material may have a
cross-section that is substantially uniform along the length of the
continuous weight material. The segmented material, meanwhile, has
one cross-section where the lead/iron material is present and a
different cross-section in the connecting spaces where only the
casing is present.
[0047] Similarly, the linear density of the continuous weight
material may remain approximately constant. This is in contrast to
the segmented material, where the sections including lead/iron have
a much higher linear density than the connecting sections. The
continuous weight material may be available in different
cross-sectional shapes and sizes to accommodate various aesthetic
and packaging concerns.
[0048] One side of the continuous weight material may be partially
or fully covered with an adhesive to allow a cut segment to be
attached to a wheel. The adhesive may be in the form of an acrylic
foam tape. A lining or backing may cover an exposed surface of the
tape to prevent the tape from sticking to the continuous weight
material when stored in a roll. In addition, the backing prevents
contaminants from reducing the effectiveness of the adhesive. For
example only, the continuous weight material may be available from
the 3M Company, such as product numbers TN2015, TN2023, and
TN4014.
[0049] For purposes of illustration only, the present disclosure
describes continuous weight material in the context of wheel/tire
assemblies. However, the systems and methods of the present
disclosure apply to other applications where additional precise
weights may be needed. For example only, precise weights may be
used in balancing other components in both automotive and
non-automotive applications. The components may be rotating
components, such as a flywheel or a driveshaft, or may be
components that reciprocate or move in another fashion. The systems
and methods of the present disclosure apply to weight balancing
even for stationary objects, where desired weight balance
parameters may be specified.
[0050] Referring now to FIGS. 1A and 1B, isometric and front views
of a continuous weight material dispensing and cutting system are
shown. A strip 102 of continuous weight material is provided from a
dispensing apparatus 104 to a cutting apparatus 106. The dispensing
apparatus 104 provides the strip 102 from a spool 110. The cutting
apparatus 106 advances the strip 102 by a specified length, and
then cuts the strip 102 to create a piece of weight material.
[0051] The dispensing apparatus 104 may create a loop 120 from the
strip 102 so that advancing of the strip 102 by the cutting
apparatus 106 does not have to be precisely synchronized with
feeding of the strip 102 by the dispensing apparatus 104. In
addition, the loop 120 provides a reserve of additional weight
material to allow the cutting apparatus 106 to continue operating
while the spool 110 is being changed. The size of the loop 120 may
be limited by a distance to the floor. The size of the loop 120 may
also be limited by the ability of the cutting apparatus 106 to pull
the weight of the weight material included in the loop 120. For
example, motor torque and/or friction may limit the amount of
weight the cutting apparatus 106 can pull.
[0052] Referring now to FIGS. 2A-2J, various views of an example
implementation of the cutting apparatus 106 are presented. The
cutting apparatus 106 includes a drive roller 130 that advances a
predetermined length of the strip 102. A cutting device 140 then
cuts the strip 102, thereby creating a piece of weight material.
Prior to reaching the drive roller 130, the strip 102 may be drawn
through an alignment assembly 150. The alignment assembly 150
ensures that the strip 102 enters at the correct orientation and
position. In various implementations, such as is shown in FIG. 2A,
the alignment assembly 150 may include first, second, and third
rollers 152, 154, and 156. In various implementations, one or more
of the first, second, and third rollers 152, 154, and 156 may be
eliminated.
[0053] The height of the first roller 152 may be adjusted based on
the cross-sectional thickness of the strip 102. The first roller
152 may be adjusted using an adjustment knob 158. In FIG. 2D, a top
view illustrates that the first roller 152 and the second and third
rollers 154 and 156 may be adjusted laterally with respect to each
other based on the cross-sectional width of the strip 102. In
various implementations, the second and third rollers 154 and 156
may be fixed, while the first roller 152 is adjusted laterally.
[0054] A first edge 162 of the first roller 152 and a first edge
164 of the second roller 154 define the track for the strip 102.
The distance between the first edges 162 and 164 may therefore be
adjusted to be equal to or slightly greater than the
cross-sectional width of the strip 102. First and second guides 166
and 168 may further prevent the strip from moving in a lateral
direction. The second guide 168 may be adjusted based on the
cross-sectional width of the strip 102. In various implementations,
the first and second guides 166 and 168 may be shortened or
eliminated altogether.
[0055] The drive roller 130 engages the strip 102 and pulls the
strip 102 underneath the cutting device 140. The drive roller 130
presses the strip 102 against an idle roller 180. This increases
the frictional force exerted on the strip 102 by the drive roller
130, thereby reducing slippage. The idle roller 180 may rotate
freely, such as on low-friction bearings, to reduce rubbing that
would otherwise occur if the drive roller 130 simply pressed the
strip 102 against a fixed surface.
[0056] The drive roller 130 may be directly driven by a stepper
motor 190. Directly driven means that the axle of the drive roller
130 is integral with or coupled in line with an output shaft of the
stepper motor 190. Directly driven therefore means that the drive
roller 130 rotates at the same angular speed as the stepper motor
190. Directly driven also means that an axis around which the drive
roller 130 rotates is approximately collinear with an axis around
which the output shaft of the stepper motor 190 rotates. One
advantage of direct driving over other coupling mechanisms, such as
gear, belt, or chain drives is that no slop or gear lash develops
over time in a direct drive system.
[0057] FIGS. 2F-2H depict example configurations for direct
driving. The stepper motor 190 is mounted to a rigid plate 191. An
output shaft 192 of the stepper motor 190 fits into a corresponding
void in a first end of a drive shaft 193. An opposite end of the
drive shaft 193 rides in a bearing 194. The drive roller 130 is
affixed to the drive shaft 193 and therefore rotates with the drive
shaft 193. One or more set screws, such as set screw 202, may
secure the drive roller 130 to the drive shaft 193.
[0058] One or more set screws 195 may secure the drive shaft 193 to
the output shaft 192. For example only, the output shaft 192 may
have a cross-section as shown in FIG. 2F, which is a circle with
two portions defined by two chords of the circle removed. Two set
screws 195 may bear against each flat section 204-1 and 204-2,
respectively, of the cross-section.
[0059] Referring now to FIG. 2G, the stepper motor 190 is secured
to a rigid motor mount 196. The drive roller 130 is affixed to a
drive shaft 197, which is supported by bearings 198. The output
shaft 192 is attached to a protruding end of the drive shaft 197 by
a coupling 199. The coupling 199 may allow for a small amount of
axial, lateral, and angular misalignment between the drive shaft
197 and the output shaft 192.
[0060] The misalignment is small and therefore the output shaft 192
and the drive shaft 197 are still approximately collinear, as
required for direct driving. For example only, an angle
misalignment of less than 1 degree and a lateral misalignment of
less than 7 thousandths of an inch may still be considered
approximately collinear with regard to the definition of direct
driving. For applications where less precision is required,
slightly more angular and lateral misalignment may be allowed, such
as 5 degrees and 50 thousandths of an inch.
[0061] Referring now to FIG. 2H, a unitary version of the drive
roller 130 is shown. The drive roller 130 incorporates an axle that
is supported by the bearings 198 and attached to the output shaft
192 of the stepper motor 190 by the coupling 199.
[0062] Referring now to FIG. 2I, end, side, and isometric views of
the drive roller 130 as shown in FIG. 2H. The drive roller 130
includes a unitary piece 278 having a roller core 280, axle ends
281 and 282, and bearing ends 283 and 284. The axle ends 281 and
282 are on either side of the roller core 280 and may have a
smaller diameter than the roller core 280. The bearing ends 283 are
on either end of the axle ends 281 and 282, respectively, and may
have a smaller diameter than the axle ends 281 and 282.
[0063] The unitary piece 278 is formed from a single piece of
material. In various implementations, the unitary piece 278 is
rough machined, such as by using a lathe, from a piece of round
stock, such as 1045 cold rolled steel. The roller core 280 is then
coated with a cover material 286, which may have a high coefficient
of friction and be more compliant than metal, such as 60-durometer
polyurethane. The cover material 286 and the bearing ends 283 may
then be finely machined, such as by using a surface grinder. In
various implementations, the axle ends 281 and 282 may also be
finely machined.
[0064] Referring back to FIG. 2A, the distance the strip 102 is
moved with each step of the stepper motor 190 depends on
configuration of the stepper motor 190 and an electrical driver of
the stepper motor 190, as well as the diameter of the drive roller
130. For example only, the distance moved with each step may be
between 7 and 8 ten thousandths of an inch, or may be four
thousandths of an inch. For example only, a system according to the
principles of the present disclosure may allow pieces of weight
material to be generated with a repeatability of approximately 0.5
or 0.25 grams.
[0065] The variation in linear density of the weight material, and
not the accuracy of the cutting system, may be the limiting factor
with regard to weight repeatability. For example only, a system
according to the principles of the present disclosure may produce
pieces of weight material whose length deviates from the desired
length (which may be calculated based on desired weight) by no more
than plus or minus 0.5%, for a total range of 1%.
[0066] The idle roller 180 is mounted in a carriage 200. The
carriage 200 may move up and down with respect to the strip 102 to
accommodate various thicknesses of the strip 102. In addition, more
or less pressure may be applied by the carriage 200 to increase the
frictional force of the idle roller 180. For example, in humid or
oily environments, the pressure applied by the carriage 200 may be
increased.
[0067] When the idle roller 180 is also driven, a second stepper
motor (not shown) may be mounted to the carriage 200 so that the
second stepper motor moves up and down with the carriage 200. The
second stepper motor directly drives the idle roller 180 in unison
with driving of the drive roller 130 by the stepper motor 190.
Alternatively, the idle roller 180 may be driven from the stepper
motor 190 via a belt/chain or gear train. In another alternative,
the stepper motor 190 may directly drive the idle roller 180, and
the drive roller 130 is allowed to idle.
[0068] Downforce of the carriage 200 may be created in various
ways. For example, air pressure may be used to press the carriage
200 against the drive roller 130. In addition, gravity may provide
downforce. Further, springs and/or hydraulic pressure may apply
downforce to the carriage 200. The air pressure or hydraulic
pressure may be calibrated using a calibration procedure and/or may
be manually set by an operator.
[0069] In various implementations, the drive roller 130 and/or the
idle roller 180 may have a raised pattern that is imprinted on the
strip as the strip passes between the drive roller 130 and the idle
roller 180. This pattern may have aesthetic value. In addition, the
raised pattern may offer a better grip of the strip 102, reducing
slippage.
[0070] The stepper motor 190 is electronically controlled to
advance a predetermined amount of the strip 102 past the cutting
device 140. Once this predetermined amount has been fed, the
cutting device 140 actuates a blade 210 to cut a piece off of the
strip 102. For example only, the cutting device 140 may be actuated
by air pressure.
[0071] As shown in more detail with respect to FIG. 2J, the blade
210 may be positioned so that the cutting edge is not perpendicular
to the direction of travel of the blade 210. This causes the edge
of the blade 210 to meet the strip 102 at a single point, which
maximizes the cutting force of the blade 210, similar to an angled
guillotine. The blade 210 may be a standard trapezoidally shaped
utility knife blade. The blade may be secured in a cartridge that
is mounted to the cutting device 140 without using tools for quick
replacement. For example only, the cartridge may be secured by
thumbscrews.
[0072] A slit 212 may be located beneath the blade 210. The blade
210 can therefore travel past the bottom of the strip 102, insuring
a complete cut. The slit 212 may be only slightly wider than the
thickness of the blade 210, thereby providing support on either
side of the blade 210. This prevents the strip 102 from being
pressed through the slit 212 by the blade 210, especially as the
blade 210 dulls.
[0073] A shoe 220 may hold down the cut piece of material as the
blade 210 retracts. The cut piece of weight material then falls
free of the cutting apparatus 106. The shoe 220 may not contact a
cut piece of weight material that is very short. In various
implementations, a transport system, such as a conveyor, may take
the cut piece of weight material from the location of the cutting
apparatus 106 to a location where the piece of weight material will
be applied.
[0074] Locating the cutting apparatus 106 away from the application
location may be necessary to accommodate space constraints.
Alternatively, bins may be located adjacent to the cutting
apparatus 106. For example only, first and second bins 240 and 242
may be provided. The first and second bins 240 and 242 may
correspond to first and second pieces of weight material for a
given wheel/tire assembly. Each wheel/tire assembly may have two
locations for application of wheel weight.
[0075] The first piece of weight material will be retrieved from
the first bin 240 and applied to the first location, while the
second piece of weight material will be retrieved from the second
bin 242 and applied to the second location. A light may be
associated with each of the bins 240 and 242 and may be illuminated
to indicate from which of the bins 240 and 242 a piece of weight
material should be retrieved.
[0076] A first diverter 250 may direct a piece of cut weight
material from the cutting apparatus 106 to the first bin 240. A
first actuator 252 may move the diverter 250 to the side, thereby
allowing a piece of cut weight material to fall to a second
diverter 254, which then directs the cut weight material to the
second bin 242. A second actuator 256 may move the second diverter
254 to the side. When both the first and second diverters 250 and
254 are moved to the side, the cut piece of weight material may
fall into a discard bin.
[0077] For example, as described in more detail below, when a
spliced section of the strip 102 is detected, the spliced section
may be cut and discarded. In addition, pieces used for calibration
and pieces at the beginning or end of a supply of weight material
may be discarded. For example only, the first and second actuators
252 and 256 may be electrically powered or may be actuated by air
pressure. A suction system may be used to remove the discarded
pieces of weight material. The suction system may also dispose of
the weight material backing when it is removed to apply the weight
material to the wheel/tire assembly.
[0078] In various implementations, the backing material may be
removed before the cut piece of weight material reaches the first
diverter 250. For example, the backing material may be removed as
the strip 102 passes the drive roller 130. In such a system, system
components that will come into contact with the cut piece may be
made from or coated with a nonstick coating. For example, the first
and second diverters 250 and 254 and the first and second bins 240
and 242 may be plasma coated or coated with polytetrafluoroethylene
(PTFE) or its equivalents.
[0079] The weight material may be applied by human operator or by a
robot, with or without human assistance. A robotic application unit
may be implemented in the system. The robotic application unit may
retrieve the cut piece of weight material and apply the cut piece
of weight material to an end effector. In various implementations,
the robotic application unit may hold the piece of weight material
with the end effector prior to the material being cut, eliminating
the need to pick up the cut piece of weight material. The end
effector may hold the material using any suitable system, including
magnetic, vacuum, and/or mechanical gripping systems.
[0080] The robotic application unit then transports the piece of
cut weight material to the wheel/tire assembly, where the end
effector presses the piece of weight material against the
appropriate spot on the wheel/tire assembly. In various
implementations, a backing material with the weight material is
removed by a second gripping apparatus. Alternatively, a vacuum may
be used to remove the backing. The backing may be disposed of via a
suction system.
[0081] Once the piece of weight material has been applied to the
wheel/tire assembly, pressure may be applied across the length of
the piece of weight material to wet out the piece of weight
material. This pressure may be applied by the end effector or by a
second end effector.
[0082] In order for an operator to accurately place a piece of
weight material on a given position of a wheel/tire assembly, a
witness mark may be added to the piece of weight material by the
cutting apparatus 106. The witness mark can then be aligned with a
corresponding witness mark on the wheel.
[0083] For example only, a scribe cylinder 260 may be used to
scribe a mark on the side of the strip 102. To accomplish this, the
stepper motor 190 may advance half of the desired length of the
strip 102, at which point the scribe cylinder 260 makes a scribe
mark on the strip 102. The stepper motor 190 then advances the
remaining portion of the desired length of the strip 102. Once the
cutting device 140 cuts the piece of weight material from the strip
102, the scribe mark is located in the middle of the resulting
piece.
[0084] The scribe cylinder 260 may actuate a scribe head 262 that
creates an indentation on the side of the strip 102. For example
only, the scribe cylinder 260 may be controlled by air pressure.
Sensors may detect whether the various components of the system are
operating correctly. For example only, sensors may measure whether
the scribe cylinder 260 is actuating fully and whether the cutting
device 140 is actuating fully.
[0085] A control enclosure 270 may include electronics that control
the stepper motor 190, and when present, the second stepper motor.
The stepper motor 190 and the second stepper motor may both receive
the same electrical signals to ensure that they operate in unison.
The electronics may include one or more processors and circuitry
that performs some or all of the functions shown in FIG. 3. The
control enclosure 270 may also include pneumatic and/or hydraulic
control devices, such as solenoids. These solenoids may be
electrically controlled to provide air and/or hydraulic pressure at
various times, such as to actuate the blade 210 and the scribe
cylinder 260. An air regulator with moisture separator may assure a
clean air supply for pneumatic components.
[0086] In various implementations, the control enclosure 270 may
include electronics that control both the dispensing apparatus 104
and the cutting apparatus 106. The control enclosure 270 may be
separate from, or separable from, the remainder of the cutting
apparatus 106. One or more wired or wireless links may allow
communication between the control enclosure 270 and the cutting
apparatus 106. In addition, one or more wired or wireless links may
allow communication between the control enclosure 270 and the
dispensing apparatus 104. The control enclosure 270 may provide one
or more power supplies to the cutting apparatus 106 and/or the
dispensing apparatus 104.
[0087] Referring now to FIG. 2J, the blade 210 is secured in a
cartridge 214 by set screws 216. The cartridge 214 may slide onto a
track of the cutting device 140 and be secured by one or more
thumbscrews (not shown).
[0088] Referring now to FIG. 3, a functional block diagram of an
example control system of the control enclosure 270 is presented. A
central control module 302 may receive weight data from a data
receiver module 306. The data receiver module 306 may receive
desired weight values from a balancing machine. For example only,
the data receiver module 306 may receive data over a serial
interface, a parallel interface, a factory control network, a local
area network, or a direct electrical interface. For example only,
supported communication protocols may include Ethernet, Datahighway
Plus (DH+), controller area network (CAN), and DeviceNet. In
various implementations, while the data receiver module 306
receives the desired weight values from the balancing machine, the
desired weight values are transferred via another apparatus, such
as a conveyor system, an upper-level system, a plant management
system, and a data tracking system.
[0089] In various implementations, the data receiver module 306 may
have a conversion front end (not shown) and a reference interface,
such as RS-232. The conversion front end converts an incoming
interface to the reference interface. In this way, the conversion
front end can be replaced when a new external interface is used,
while retaining RS-232 for internal communication.
[0090] The data receiver module 306 may receive two weight values
for each wheel/tire assembly. The central control module 302
provides weight values to a length converter module 310, which
converts the weight values into length values. This conversion is
based on the linear density of the weight material, a value that
may be stored in a linear density storage module 314.
[0091] The central control module 302 may provide a linear density
value to the linear density storage module 314. Alternatively, the
linear density storage module 314 may be preprogrammed with values
of linear density for various available weight materials. The
central control module 302 may then indicate to the linear density
storage module 314 which material is being used.
[0092] In various implementations, the weight to length conversion
may be performed by dividing the desired weight by the linear
density of the weight material in use. The central control module
302 may communicate with an operator input/output device 318. The
operator input/output device 318 may provide sensory feedback to an
operator and/or may receive input from the operator.
[0093] For example only, the operator input/output device 318 may
allow for the operator to supply the linear density of the weight
material being used. Alternatively, the operator may indicate which
weight material is being used, and the central control module 302
will select the corresponding linear density in the linear density
storage module 314.
[0094] In other implementations, the operator input/output device
318 may offer the operator a selection of linear densities, from
which the operator selects the correct linear density. In various
implementations, various sensors may be present to determine the
material's linear density. For example only, a calibration scale
may be implemented. The central control module 302 may cause a
predetermined length of material to be cut. The weight of this
length of material, as measured by a calibration scale, and the
requested length can be used to calculate linear density.
[0095] Alternatively, the calibration scale may be used to verify
accuracy of the system. If the linear density as calculated based
on the weight measured by the calibration scale does not match the
expected density, the scale may be out of calibration, the material
may be different than expected, and/or length errors may be
present. This calibration process may also be manually initiated
via the operator input/output device 318.
[0096] In various implementations, the central control module 302
may determine linear density of the weight material based on the
cross-sectional profile of the weight material. The central control
module 302 may include one or more sensors that determine the
cross-sectional profile of the weight material. Based on these
sensors, the central control module 302 can select or calculate the
linear density of the weight material. In various implementations,
the volumetric density of the weight material may remain
approximately constant. The linear density can thereby be
calculated from the volumetric density based on the cross-sectional
area of the weight material.
[0097] Once the central control module 302 has determined a desired
length to which to cut the weight material, the central control
module 302 provides this length to a stepper actuator control
module 322. The central control module 302 may convert the desired
length into a number of steps for the stepper motor 190 and provide
the length in units of steps.
[0098] The stepper actuator control module 322 then controls the
stepper motor 190 to advance by the requested number of steps. Once
the stepper actuator control module 322 has finished its movement,
the stepper actuator control module 322 may transmit a completion
signal to the central control module 302.
[0099] The central control module 302 may then request that a
cutter actuator control module 326 actuate the cutting device 140.
For example only, the cutter actuator control module 326 may
energize a solenoid that allows air pressure to flow to the cutting
device 140, thereby forcing the blade 210 through the weight
material.
[0100] In various implementations, the central control module 302
may apply a scribe mark to the piece of weight material. Whether
the scribe mark is applied, and to where the scribe mark is
applied, may be determined by operator input from the operator
input/output device 318. When a scribe mark will be added to the
center of the piece, the central control module 302 may provide
half the desired length to the stepper actuator control module
322.
[0101] After completion of this half length, the central control
module 302 provides a signal to the scribe actuator control module
330. The scribe actuator control module 330 then actuates then
actuates the scribe cylinder 260 to create the scribe mark. The
central control module 302 then provides the remaining half length
to the stepper actuator control module 322.
[0102] Once the stepper actuator control module 322 signals that
the stepper motor 190 has advanced through the second half of the
length, the central control module 302 then instructs the cutter
actuator control module 326 to cut the weight material. The scribe
mark will then be in the center of the cut piece.
[0103] The central control module 302 may provide commands to a
diverter actuator control module 334. The diverter actuator control
module 334 may direct cut pieces between different locations. For
example only, the diverter actuator control module 334 may direct a
cut piece between one or more bins and a discard bin. The diverter
actuator control module 334 may also illuminate a light
corresponding to the bin where the cut piece is located for
retrieval by the operator.
[0104] The stepper motor 190 drives the drive roller 130. The
downforce of the carriage 200 against the weight material
determines the frictional force, which prevents the weight material
from slipping against the drive roller 130. The central control
module 302 may modulate the amount of downforce via a carriage
downforce control module 338. In various implementations, the
carriage downforce control module 338 may control hydraulic and/or
air pressure pressing the carriage 200 against the idle roller
180.
[0105] The central control module 302 may receive inputs from one
or more safety sensors 342. For example only, the safety sensors
342 may sense whether maintenance doors are open. The central
control module 302 may halt operation of various components, such
as the cutter actuator control module 326 and the scribe actuator
control module 330, when any of the safety sensors 342 indicate
that a maintenance door is open.
[0106] This prevents the operator from coming in contact with
moving parts. Emergency stop switches (not shown) may be located at
various locations on both the cutting apparatus 106 and the
dispensing apparatus 104. The emergency stop switches also halt
operation of various components. This prevents operator injury and
equipment damage in event of a fault.
[0107] In various implementations, the stepper actuator control
module 322 may still be active when maintenance doors are open. The
stepper actuator control module 322 may control the stepper motor
190 to advance, thereby drawing in new weight material when a new
roll is begun. The operator may signal via the operator
input/output device 318 to the central control module 302 that a
new piece of material is being loaded. The stepper actuator control
module 322 may then begin advancing the stepper motor 190 to draw
in the new weight material.
[0108] A material detection module 346 may detect whether weight
material is present. For example only, the material detection
module 346 may detect once the roll of weight material has been
used up. In this way, the central control module 302 can stop
operation and not inadvertently output the last piece, which may be
too short due to the weight material running out.
[0109] In addition, the central control module 302 will halt
actuating the scribe cylinder 260 and the cutting device 140 when
no weight material is present. When loading new material, the
material detection module 346 may detect that the new weight
material is present. The central control module 302 may then direct
the stepper actuator control module 322 to advance the stepper
motor 190 to draw the material into the cutting apparatus 106. The
material detection module 346 may use various types of sensors. For
example only, the material detection module 346 may interface with
a photoelectric sensor, a mechanical sensor, an infrared sensor,
and/or an ultrasonic sensor.
[0110] A splice detection module 350 may detect splices in the
weight material. When one roll of weight material ends, a new roll
of weight material can be spliced to the end of the old roll. In
this way, operation is continuous, without having to feed a new
roll of weight material. However, the splice itself may not be
desirable for placing on a wheel/tire assembly.
[0111] Therefore, when the splice detection module 350 detects a
splice, the central control module 302 may advance the length of
the splice, cut the splice, and instruct the diverter actuator
control module 334 to discard the material surrounding the splice.
After a splice, a predetermined length of the new weight material
may be cut and weighed to determine the linear density of the new
weight material.
[0112] Splices may be created with adhesives that have different
material properties than the surrounding weight material. For
example only, the splicing material may be adhesive tape. The
adhesive tape may have a higher optical reflectivity than the
surrounding weight material. This change in optical reflectivity
may be sensed by the splice detection module 350 as a splice.
[0113] In another example, electrical properties of the adhesive
tape, such as magnetic permeability, may be different than the
surrounding weight material. Alternatively, the splicing material
may not be detectable by itself; additional material is added to
allow for detection. For example only, the splicing tape may be
undetectable, so reflective tape is applied over the splice.
[0114] The operator input/output device 318 may allow the operator
to repeat the previous cut. For example, this feature may be used
when a piece of weight material is dropped or misplaced. The
operator input/output device 318 may also allow an operator to
manually cut a piece of weight material to a given length or having
a given weight. This may be useful when integrating with balancing
machines that do not output weights in a digital format.
[0115] When integrating a system according to the present
disclosure with prior art lead balancing stations, a large number
of bins may be present, each having a different size of lead
weight. The operator input/output device 318 may allow the operator
to cut a predetermined number of pieces of a certain weight to
replace the lead weights in one bin with cut pieces of the
continuous weight material.
[0116] The operator input/output device 318 may allow the user to
enter an upper limit and a lower limit, to define a range of
weights, as well as an increment. The central control module 302
can then cut a predetermined number of pieces of each increment of
weight, from the lower limit to the upper limit. In various
implementations, control may pause between each increment, so the
cut pieces can be removed from a collection bin and placed in the
correct bin previously occupied by the lead weights. The operator
can then signal via the operator input/output device 318 to begin
cutting the next increment.
[0117] In various implementations, the operator input/output device
318 may be separate from, or separable from, the control enclosure
270. The control enclosure 270 may be separate from the cutting
apparatus 106, the dispensing apparatus 104, and the operator
input/output device 318. The control enclosure 270 may then be
placed at any convenient location. Being separate, the operator
input/output device 318 may be placed so as to best be accessible
to the operator. By separating components, shipping, packaging,
service, and replacement may be made easier and more
cost-effective.
[0118] Referring now to FIG. 4A-4D, various views of an example
implementation of the dispensing apparatus 104 are presented.
Weight material may be purchased and stored on the spool 110. The
spool 110 is loaded into the dispensing apparatus 104 by opening
first and second doors 408 and 412. The first and second doors 408
and 412 protect the operator from moving parts and may prevent
debris from entering the dispensing apparatus 104.
[0119] The spool 110 has first and second ends 414 and 416 whose
diameters are larger than the diameter of a center portion 418 of
the spool 110. The first and second ends 414 and 416 ride on first
and second axles 420 and 422. Each of the axles 420 and 422 may
have a flanged roller, which correspond to the first and second
ends 414 and 416. The flange of the flanged rollers prevents the
spool 110 from moving in an axial direction along the axles 420 and
422.
[0120] In various implementations, a second spool (not shown) may
be stored in the dispensing apparatus 104. The second spool may be
located directed above the spool 110. The second spool may be
stored in the dispensing apparatus 104 simply to be located
conveniently. However, in various implementations, the dispensing
apparatus 104 may include machinery that, once the spool 110 is
removed, guides the second spool into the previous location of the
spool 110. In fact, the dispensing apparatus 104 may include
automated machinery that automatically (or upon actuation of a
button or other operator input) replaces the spool 110 with the
second spool.
[0121] As shown in FIGS. 4C-4D, the first and second axles 420 and
422 may be coupled via a chain or a belt. This causes the first and
second axles 420 and 422 to rotate together. The first and second
axles 420 and 422 may be driven by a motor 430 via another belt or
chain. The motor 430 turns the first and second axles 420 and 422
in order to dispense more weight material from the spool 110.
[0122] Weight material from the spool 110 passes through first,
second, and third rollers 440, 442, and 444. The weight material
then passes through a splicing apparatus 450, which will be
described in more detail below. In various implementations, the
splicing apparatus 450 may be located in another position, such as
on the exterior of the dispensing apparatus 104. The splicing
apparatus 450 may be portable, and may be handheld--when not in
use, the splicing apparatus 450 may then be temporarily affixed to
the dispensing apparatus 104. The weight material then passes over
a pulley 460. The pulley 460 is driven by a motor 464. The motor
464 turns the pulley 460 to provide the loop 120 of weight
material.
[0123] The size of the loop 120 may be determined by operating
requirements of the system and may be set to provide enough weight
material so that a splice can be made while operation continues
unabated using material from the loop 120. An idle roller 468
applies pressure to the weight material to keep the weight material
from slipping against the pulley 460. Downforce is applied to the
idle roller 468 by a downforce device 470. For example only, the
downforce device 470 may include a spring. Alternatively, the
downforce device 470 may be fixed in place, creating a fixed gap
between the idle roller 468 and the pulley 460.
[0124] The dispensing apparatus 104 may include one or more sensors
to determine the length of the loop 120. For example, as shown in
FIGS. 4A and 4B, the dispensing apparatus 104 may include sensors
474-1, 474-2, and 474-3. If the length of the loop 120 decreases
below a predetermined distance, operation of the cutting apparatus
106 may be halted to prevent the weight material from being pulled
taught and slipping in the cutting apparatus 106.
[0125] The motor 464 may drive the pulley 460 to establish a
predetermined length of the loop 120. When splicing is being
performed, the motor 464 may fix the position of the pulley 460 to
keep the strip 102 from moving and allow precise splicing. When
splicing, the trailing end of the previous roll of weight material
may be centered in the splicing apparatus 450. The previous spool
110 can be removed and replaced with a new spool 110 containing a
new roll of weight material.
[0126] The new weight material may be threaded through the rollers
440, 442, and 444 so that the leading end of the new weight
material butts up against the trailing end of the previous roll of
weight material. The two ends are then joined. For example only, a
length of adhesive tape may be present at the splicing apparatus
450. In order to join the leading end of the new weight material to
the trailing end of the previous weight material, the operator may
apply the piece of tape to the ends and apply enough pressure to
ensure adhesion.
[0127] In addition, splice indicia may be applied to the weight
material. For example only, reflective tape may be applied to allow
for detection of the splice. Alternatively, marks, paint, or other
indicia may be applied to the weight material. Once the splice is
completed, the motor 464 may drive the pulley 460 to reestablish
the desired length of the loop 120. The dispensing apparatus 104
may be designed to isolate access to the splicing apparatus 450
from access to the spool 110. In this way, the splicing apparatus
450 can only be accessed once the spool 110 is loaded and
associated safety doors are closed. Then, the splice can be
performed without exposing the operator to the mechanics of the
motor 430 and the first and second axles 420 and 422.
[0128] For example only, during normal operation (when not
splicing), the motor 464 may drive the pulley 460 such that a
bottom of the loop 120 remains between the sensors 474-1 and 474-2.
In various implementations, the sensors 474-1, 474-2, and 474-3 may
be photoelectric sensors. The sensors 474-1, 474-2, and 474-3 may
be diffuse sensors, which include both a light emitter and a
detector, eliminating the need for separate light emitters or
detectors on an opposite side of the loop 120.
[0129] When a splice is desired, the motor 464 may drive the pulley
460 to lower the bottom of the loop 120 to the sensor 474-3. In
various implementations, once the bottom of the loop 120 reaches
the sensor 474-3, the motor 464 may drive the pulley 460 a
predetermined further amount, to lower the bottom of the loop 120 a
predetermined distance below the sensor 474-3.
[0130] Alternatively, for splicing, the motor 464 may drive the
pulley 460 until a trailing end of the weight material is located
at a predetermined location (such as the middle) of the splicing
apparatus 450. However, even if the trailing end has not yet
reached the predetermined location of the splicing apparatus 450,
the motor 464 may halt movement of the pulley 460 once the bottom
of the loop 120 reaches the sensor 474-3, or at a predetermined
distance thereafter. Once the bottom of the loop rises above the
sensor 474-3, the motor 464 may once again actuate the pulley 460
to attempt to bring the trailing end of the weight material to the
predetermined location of the splicing apparatus 450. Once splicing
is complete, the motor 464 may resume controlling the bottom of the
loop 120 to be between the sensors 474-1 and 474-2.
[0131] The motor 430 drives the first and second axles 420 and 422
in order to provide slack material from the spool 110. In this way,
the frictional force required between the weight material and the
pulley 460 is reduced. The spool 110 may be installed in such a way
that a bottom loop 480 is created below the spool 110. A dancer
switch 484 detects the height of the bottom loop 480.
[0132] The dancer switch 484 includes a rod 488 arranged in a
direction perpendicular to the plane of FIG. 4D. The rod rides
along the inside of the bottom loop 480. The dancer switch 484
pivots about a pivot point 490. As the bottom loop 480 moves up,
indicating less slack is available, the dancer switch 484 pivots
about the pivot point 490. A sensor 494 across the pivot point 490
from the rod 488 detects this condition and instructs the motor 430
to rotate the first and second axles 420 and 422 to provide more
slack material.
[0133] Referring now to FIG. 5, an isometric view of an example
implementation of the splicing apparatus 450 is presented. First
and second clamps 502 and 504 are mounted to a base plate 508. The
first clamp 502 clamps the trailing end of the old weight material
between a first shoe 510 and the base plate 508. The second clamp
504 clamps the leading end of the new roll of weight material
between a second shoe 512 and the base plate 508. Adhesive tape
(and, optionally, splice indicia, such as reflective tape) may be
applied manually by an operator or by a mechanical apparatus. Once
the splice has been accomplished, the first and second clamps 502
and 504 are released.
[0134] Referring now to FIG. 6, a block diagram of an example wheel
balancing system 600 is presented. A feeder 604 provides a wheel to
a balancer 608. For example only, the feeder 604 may include a
conveyor system or another suitable system for providing the wheel
to the balancer 608. FIGS. 7A and 7B include views of an example
wheel 704 with a tire 708 mounted on the wheel 704. When the wheel
704 is mounted on a car, one side of the wheel will be facing in
toward the middle of the car and the other side will be facing out
away from the car. The side facing in is referred to here as the
carside and the side facing out is referred to as the curbside.
[0135] FIG. 7A includes an example perspective view from the
carside of the wheel 704 and the tire 708. FIG. 7B includes an
axial, cross-sectional view of the wheel 704 and tire 708 with the
carside of the wheel 704 down. Referring now to FIGS. 7A and 7B,
the wheel 704 includes a mounting surface 712 where the wheel 704
mates with a rotating portion of a vehicle (e.g., a rotor or hub)
if the wheel 704 is mounted to a vehicle. The mounting surface 712
may include one or more apertures 716 through which a mounting stud
of the vehicle or a lug bolt may extend. A plane that is flush with
the mounting surface 712 is referred to as a mounting plane
714.
[0136] The inner surface of wheel 704 may have one or more
predetermined surfaces where the weight material can be attached to
the wheel 704. For example only, the wheel 704 may include two
predetermined surfaces, such as first and second predetermined
surfaces 718 and 720, where the weight material can be attached to
the inner surface of the wheel 704. The example of FIG. 7B shows
pieces of weight material attached to the wheel 704 within the
first and second predetermined surfaces 718 and 720.
[0137] Each of the predetermined surfaces can be thought of as
defining a cylinder or a conical frustum. A conical frustum is a
cone with the top sliced off parallel to the base, and can look
like a tapered cylinder. Each of the predetermined surfaces can be
referred to as a plane. For example only, the cylindrical or
frustum shaped portion of the interior surface of the wheel 704
defined by the first predetermined surface 718 will hereafter be
referred to as the midplane of the wheel 704. The cylindrical or
frustum shaped portion of the interior surface of the wheel 704
defined by the second predetermined surface 720 will hereafter be
referred to as the lowerplane of the wheel 704. The width of the
strip 102 of the weight material may be selected such that the
width of the strip 102 is less than or equal to the narrower one of
the midplane 718 and the lowerplane 720. In various
implementations, the width of the midplane 718 and the lowerplane
720 may be equal.
[0138] The midplane 718 and the lowerplane 720 are each defined by
two parallel planes. For example only, the midplane 718 is defined
by an inner (or carside) plane 717 and an outer (or curbside) plane
719. The lowerplane 720 may be defined by an inner plane 721 and an
outer plane 723. A distance between the mounting plane 714 and an
inner plane in a direction parallel to a rotational axis 722 of the
wheel 704 can be referred to as the offset of the associated plane.
For example only, a distance 724 between the mounting plane 714 and
the inner plane 717 of the midplane 718 will be referred to as a
first offset. A distance 728 between the mounting plane 714 and the
inner plane 721 of the lowerplane 720 will be referred to as a
second offset.
[0139] A radial distance between the axis 722 and an inner plane in
a radial direction from the axis 722 will be referred to as a
radius. For example only, a distance 732 between the axis 722 and
the inner plane 717 of the midplane 718 will be referred to as a
first radius. A distance 736 between the axis 722 and the inner
plane 721 of the lowerplane 720 will be referred to as a second
radius.
[0140] Referring back to FIG. 6, the balancer 608 spins the wheel
in a predetermined manner to determine how to balance the wheel
both side-to-side (i.e., curbside to carside) and rotationally.
Based on predetermined characteristics of the wheel and
measurements taken during the spinning, the balancer 608 generates
balancing data for the wheel. The balancer 608 may also apply
visual markers to the wheel where balancing weights should be
applied.
[0141] For example only, the balancing data includes first and
second desired weights 610. The first and second desired weights
610 indicate how much of the weight material to apply within the
midplane and the lowerplane, respectively, of the wheel. A dispense
and cut system (DCS) 612 determines a desired length of a first
piece of the weight material based on the first desired weight. The
DCS 612 also determines a desired length of a second piece of the
weight material based on the second desired weight.
[0142] A robotic arm moves an end of arm tool (EOAT), collectively
illustrated in FIG. 6 by 616, to receive the first and second
pieces of the weight material 614 and may assist the DCS 612 in
cutting the pieces 614 of the weight material. In various
implementations, the robotic arm is capable of compound,
multi-axial movement. The EOAT is attached to a distal end of the
arm.
[0143] The balancing data also includes first and second angles,
the first and second offsets, and the first and second radii (or
radiuses) 620. The first angle indicates an angle, measured
relative to a reference angle, at which a midpoint of the first
piece of the weight material should be applied within the midplane.
The second angle indicates an angle, measured relative to the
reference angle, at which a midpoint of the second piece of the
weight material should be applied within the lowerplane. For
example only, the reference angle may be at a 12:00 position of the
wheel, an angle at which the valve stem opening is present, or
another suitable reference angle.
[0144] A crowder 624 centers the wheel about a reference axis. For
example only, the crowder 624 may include a four-post crowding
mechanism where the four posts are drawn towards the reference axis
to center the wheel about the reference axis while minimizing
rotation of the wheel. The first and second pieces of the weight
material may be applied at a weight application station 628. In
various implementations, the crowder 624 may be implemented
separately from the weight application station 628. Once the wheel
is centered by the crowder 624, the robotic arm and EOAT 616
selectively moves to apply the last cut ends of the first and
second pieces of the weight material within the midplane and the
lowerplane beginning at the first and second desired angles,
respectively. In this manner, the wheel is balanced.
[0145] Referring now to FIGS. 8A and 8B, a side view 804 and a
front view 808, respectively, of an example implementation of the
arm with the EOAT 616, the weight application station 628, and the
crowder 624 are presented. In various implementations, the wheel
may be provided to a weight application station via a conveyer
system 812 or in another suitable manner. For example only, the
wheel may be provided to the weight application station with the
carside of the wheel facing down on the conveyer. An opening 816 in
the conveyer system 812 may be provided at the weight application
station through which the arm and EOAT 616 may access the interior
of the wheel from below the conveyer system 812. In various
implementations, the wheel may be provided to the weight
application station with the curb side of the wheel down on the
conveyer system 812, and the arm and EOAT 616 may access the
interior surfaces of the wheel from above.
[0146] FIGS. 9A-9D include various isometric views of an example
implementation of the cutting apparatus 106 of the DCS 612. The
cutting apparatus 106 of the present application may include a
backing material removal system. FIGS. 9E-9H include various
isometric views of an example implementation of a backing removal
system 910. Referring to FIGS. 9A-9H, in various implementations,
the strip may be provided to the cutting apparatus 106 with the
backing 904 facing up and with the weight material 908 facing down.
In this manner, the adhesive side of the strip faces up.
[0147] For example only, the backing material removal system 910
may include a removal roller 912 and a tensioner roller system 916.
A leading edge 920 of the backing 904 may be peeled away from the
weight material 908 (e.g., by an operator initially). The leading
edge 920 of the backing 904 may be provided to a driven roller
assembly 911 via an idle roller 913 and a weighted roller assembly
914.
[0148] A biasing mechanism 915 (e.g., a spring) biases a driven
roller 917 of the driven roller assembly 911 toward an idle roller
918. The driven roller 917 holds the backing 904 in place when the
driven roller 917 is not being driven. The driven roller 917 may be
driven in tandem with the drive roller 130. In various
implementations, the driven roller 917 may be driven independently
of the drive roller 130.
[0149] For example only, the driven roller 917 may be driven when
the weighted roller assembly 914 reaches a predetermined position
as indicated by a position sensor assembly 919. In the example
embodiment, the weighted roller assembly 914 is implemented in a
key-hole arrangement where the weighted roller assembly 914 moves
up and down within a guide 921. In various implementations, other
types of arrangements may be used, such as an arrangement involving
Thompson shafts, THK rails, or another suitable arrangement.
[0150] Because the driven roller 917 holds the backing 904 in place
when the driven roller 917 is not being driven, the weighted roller
assembly 914 may slide down the guide 921 toward the predetermined
position as the weight material 908 is dispensed past the removal
roller 912. The position sensor assembly 919 may include a position
sensor and a stop. The position sensor monitors the position of the
weighted roller assembly 914 within the guide 921.
[0151] When the position of the weighted roller assembly 914
reaches the predetermined position, the driven roller 917 may be
driven. In various implementations, the driven roller 917 may be
driven a predetermined amount (e.g., angle). The predetermined
amount may be set to lift the weighted roller assembly 914 to a
second predetermined position. In other implementations, the driven
roller assembly 917 may be driven until the position sensor
assembly 919 indicates that the weighted roller assembly 914 is in
the second predetermined position. When the weighted roller
assembly 914 is between the first and second predetermined
positions, the weighted roller assembly 914 and the driven roller
917 maintain tension on the backing 904 such that the backing 904
is removed from the weight material 908 as the weight material 908
is dispensed past the removal roller 912. If rolls of the strip 102
are spliced together, the splice may splice the backing 904 so the
backing material removal system will continue to remove the backing
904 even after a splice in the strip 102.
[0152] Referring now to FIGS. 10A-10H, various isometric views of
the cutting apparatus 106 are shown. As stated above, the slit 212
may be implemented in the cutting apparatus 106 below the blade 210
in various implementations. For purposes of the present disclosure,
however, the cutting apparatus 106 includes only a cutting
apparatus edge 924 of a slit. A leading edge of the EOAT, as
discussed further below, will provide a dispense edge of the slit.
The blade 210 passes through this slit to cut the weight
material.
[0153] A deck 928 of the cutting apparatus 106 may be tapered
inward toward the drive roller 130 from the cutting apparatus edge
924 of the slit. The tapered face of the deck 928 is illustrated at
932. The tapered face 932 may enable the leading edge of the EOAT
to be moved into a cutting position from behind the blade 210.
[0154] The cutting apparatus 106 includes an arm 1004 with an EOAT
that is generally illustrated by 1008. The EOAT 1008 includes a
first wet out tool 1012 and a second wet out tool 1016. The EOAT
1008 may also be referred to as an end effector. A wet out tool may
also be referred to as a wet out shoe.
[0155] The first wet out tool 1012 includes a leading edge 1020 of
an arc shaped face 1024 and a trailing edge 1028 of the arc shaped
face 1024. The second wet out tool 1016 includes a leading edge
1032 of an arc shaped face 1036 and a trailing edge 1040 of the arc
shaped face 1036.
[0156] When the EOAT 1008 is away from the cutting position, the
cutting apparatus 106 may dispense a first piece 1044 of the weight
material past the cutting apparatus edge 924 and the blade 210. In
various implementations, the cutting apparatus 106 may dispense the
first piece 1044 of the weight material past the cutting apparatus
edge 924 while the first wet out tool 1012 is in the cutting
position or in a final cutting position.
[0157] The first piece 1044 includes a previously cut end 1048. The
weight material may curve in a downward direction, such as shown in
the example illustration of FIG. 10A, when dispensed past the
cutting apparatus edge 924. The downward curve may be attributable
to, for example, gravity, a shape taken by the weight material from
being stored on a roll, and/or one or more other forces.
[0158] As shown in FIG. 10B, the leading edge 1020 of the first wet
out tool 1012 may first be moved up to the cutting position. When
in the cutting position, the slit is formed between the cutting
apparatus edge 924 and the leading edge 1020 of the first wet out
tool 1012. A wet out tool may be said to be in the cutting position
when a distance between a leading edge of the wet out tool and the
cutting apparatus edge 924 is approximately equal to a
predetermined distance. The predetermined distance may be only
slightly wider than the thickness of the blade 210 such that the
leading edge of the wet out tool and the cutting apparatus edge 924
provide support on both sides of the blade 210. This prevents the
weight material 908 from being pressed through the slit between the
leading edge of the wet out tool and the cutting apparatus edge 924
by the blade 210, especially as the blade 210 dulls.
[0159] Once the leading edge 1020 of the first wet out tool 1012 is
in the cutting position, the arm 1004 may be actuated to rotate the
first wet out tool 1012 upward about the leading edge 1020 to a
final cutting position. Rotating the first wet out tool 1012 upward
about the leading edge 1020 of the first wet out tool 1012 while
the first piece 1044 is dispensed may cause the first piece 1044 to
lay flatly on the arc shaped face 1024 of the first wet out tool
1012. As stated above, in various implementations, the first piece
1044 may be dispensed after the first wet out tool 1012 is in the
final cutting position. The first piece 1044 laying flatly on the
arc shaped face 1024 of the first wet out tool 1012 when the first
wet out tool 1012 is in the final cutting position is illustrated
in FIG. 10C.
[0160] Once the first wet out tool 1012 reaches the final cutting
position, an in position signal may be provided to the central
control module 302 of the cutting apparatus 106. The central
control module 302 may trigger cutting of the first piece 1044 via
the cutter actuator control module 326 in response to receiving the
in position signal. In this manner, first piece 1044 of the weight
material having the desired weight is cut from the strip 102. A
newly cut end 1052 of the first piece 1044 is created by the
cutting of the first piece 1044 that is located approximately at
the leading edge 1020 of the first wet out tool 1012.
[0161] The EOAT 1008 can then be moved away from the final cutting
position. For example only, the EOAT 1008 can be moved to position
the leading edge 1032 of the second wet out tool 1016 underneath
the cutting position. FIG. 10D includes an example illustration of
the leading edge 1032 of the second wet out tool 1016 being
positioned underneath the cutting position.
[0162] When the EOAT 1008 is away from the cutting position, a
second piece 1056 of the weight material can be dispensed. Like the
first piece 1044, as discussed above, the second piece 1056 can be
dispensed once the second wet out tool 1016 is in the final cutting
position. The second piece 1056 also includes a previously cut end
1060. The cutting of the first piece 1044 may create the previously
cut end 1060 of the second piece 1056. FIG. 10E includes an example
illustration of the second piece 1056 of the weight material
dispensed.
[0163] As shown in FIG. 10F, the leading edge 1032 of the second
wet out tool 1016 may next be moved up to the cutting position.
When in the cutting position, the slit is formed between the
cutting apparatus edge 924 and the leading edge 1032 of the second
wet out tool 1016. Once the leading edge 1032 of the second wet out
tool 1016 is in the cutting position, the arm 1004 may be actuated
to rotate the second wet out tool 1016 upward about the leading
edge 1032 to the final cutting position. Rotating the second wet
out tool 1016 upward about the leading edge 1032 of the second wet
out tool 1016 while the second piece 1056 is dispensed may cause
the second piece 1056 to lay flatly on the arc shaped face 1036 of
the second wet out tool 1016. FIG. 10G illustrates the second piece
1056 laying flatly on the arc shaped face 1036 of the second wet
out tool 1016 when the second wet out tool 1016 is in the final
cutting position.
[0164] Once the second wet out tool 1016 reaches the final cutting
position, a second in position signal may be provided to the
central control module 302 of the cutting apparatus 106. The
central control module 302 may trigger cutting of the second piece
1056 via the cutter actuator control module 326 in response to
receiving the second in position signal. In this manner, the second
piece 1056 of the weight material having the desired weight is cut
from the strip 102. A newly cut end 1064 of the second piece 1056
is created by the cutting of the second piece 1056 that is located
approximately at the leading edge 1032 of the second wet out tool
1016. The first and second pieces 1044 and 1056 can then be moved
away from the cutting apparatus 106 via the EOAT 1008 for
application to the wheel as shown in the example illustration of
FIG. 10H.
[0165] Alternatively, the first and second wet out tools 1012 and
1016 may be moved to the final cutting positions prior to the
weight material being dispensed onto the first and second wet out
tools 1012 and 1016. In such implementations, FIGS. 10A, 10B, 10E,
and 10F would not apply. This alternative approach can be used when
the weight material is stiff enough that the weight material can be
pushed onto the first and second wet out tools 1012 and 1016
without bunching up.
[0166] FIGS. 11A-11G include various example views of the first and
second wet out tools 1012 and 1016. While the first wet out tool
1012 is shown and will be discussed in conjunction with FIGS.
11A-11C and 11G, the discussion may be applicable to the second wet
out tool 1016. Further, while the second wet out tool 1016 is shown
and will be discussed in conjunction with FIGS. 11D-11F, the
discussion may be applicable to the first wet out tool 1012.
[0167] Referring now to FIGS. 11A-11C, the first wet out tool 1012
may be made of a urethane or another suitable material that
provides a suitable amount of elasticity. The suitable amount of
elasticity may enable the first wet out tool 1012 to deform by at
least a predetermined amount (e.g., 4 degrees) to accommodate a
maximum possible change in the radius of the wheel present between
the inner and outer planes of the midplane of the wheel. In various
implementations, the first wet out tool 1012 may be made of another
suitable material that is less elastic than urethane, and one or
more flexible members (e.g., springs) may be provided with the
first wet out tool 1012 to enable the first wet out tool 1012 to
accommodate the maximum possible change in the wheel radius (see
FIG. 11G).
[0168] The arc shape (e.g., the radius of the arc) of the arc
shaped face 1024 of the first wet out tool 1012 may be selected,
for example, to accommodate a smallest possible wheel diameter,
such as a 12 inch wheel diameter. In various implementations, the
leading edge 1020 of the first wet out tool 1012 may be defined by
a metal edge structure (not shown) formed on top of or embedded
within the urethane of the first wet out tool 1012. The metal edge
structure may provide a suitably rigid surface against which the
weight material can be cut and that can be used to form the slit
with the cutting apparatus edge 924.
[0169] The first wet out tool 1012 may also include first and
second side faces 1104 and 1108. The arc shaped face 1024 may be
defined by the leading and trailing edges 1020 and 1028 of the
first wet out tool 1012 and by the first and second faces 1104 and
1108. The first and second faces 1104 and 1108 may extend past the
arc shaped face 1024 to create first and second flanges 1112 and
1116, respectively, of the first wet out tool 1012. The first and
second flanges 1112 and 1116 prevent lateral movement of weight
material on the first wet out tool 1012. In various
implementations, one or both of the first and second flanges 1112
and 1116 may be omitted.
[0170] The width of the arc shaped face 1024 (e.g., between the
first and second flanges 1112 and 1116) may be chosen based upon
the width of the strip 102. For example only, the width of the arc
shaped face 1024 between the first and second flanges 1112 and 1116
may be slightly (e.g., a predetermined amount) larger than the
width of the strip 102. The distance between the first and second
flanges 1112 and 1116 being only slightly larger than the width of
the strip 102 may provide lateral support for the first piece 1044
of the weight material.
[0171] The height of the first and second flanges 1112 and 1116
above the arc shaped face 1024 may be selected based upon the
height of the strip 102. For example only, the height of the first
and second flanges 1112 and 1116 above the arc shaped face 1024 may
be (e.g., a predetermined amount) less than the height of the strip
102. Fast movement of the arm 1004 may be performed in a direction
that is perpendicular to the first and second flanges 1112 and 1116
to prevent a piece of material from slipping off of the arc shaped
face 1024 during the movement.
[0172] The first wet out tool 1012 includes one or more magnetic
devices, such as magnetic devices 1130-1, 1130-2, . . . , 1130-N
(collectively referred to as magnetic devices 1130). The magnetic
devices 1130 may help attract ferrous material present in the
weight material toward the arc shaped face 1024 of the first wet
out tool 1012. In various other implementations, vacuum and/or
grippers may additionally or alternatively be used.
[0173] The magnetic devices 1130 may be natural magnets, such as
rare earth magnets, or another suitable form of magnetic device,
such as electromagnets. For example only, the magnetic devices 1130
may include neodymium. The magnetic devices 1130 may create a
magnetic field on the arc shaped face 1024 of the first wet out
tool 1012. The force of the magnetic field may be sufficient to
hold the first piece 1044 stationary on the arc shaped face 1024 of
the first wet out tool 1012 during movement of the EOAT 1008. In
various implementations, a spacing between the magnetic devices
1130 and/or the characteristics of the magnetic devices 1130 may be
chosen to create a desired magnetic field on the arc shaped face
1024 of the first wet out tool 1012. The magnetic force generated
by the magnetic devices 1130 is less than the adhesive force
holding the first piece 1044 against the wheel when the first piece
1044 is applied to the wheel. In this manner, the magnetic force
will be overcome by the adhesive force, and the first piece 1044
will be peeled off of the first wet out tool 1012 as the first
piece 1044 is applied (wet out) along the inner surface of the
wheel.
[0174] One or more apertures may be formed in the first wet out
tool 1012 for one or more material presence sensors, such as
material presence sensor 1144. While only the material presence
sensor 1144 is shown, the first wet out tool 1012 may include one
or more additional material presence sensors. The apertures may
completely extend through the first wet out tool 1012 or may extend
partially through the first wet out tool 1012. The material
presence sensors may include, for example, fiber optic sensors that
generate signals based on proximity of a surface to the fiber optic
sensor. For another example only, the material presence detection
sensors may be diffuse type photo-electric sensors. The signals
output by the material presence sensors can be used to determine
whether weight material is present on the arc shaped face 1024 of
the first wet out tool 1012. For example only, the signals output
by one or more of the material presence sensors may be used after
the first wet out tool 1012 has been moved away from the cutting
position to ensure that the first piece 1044 has been deposited on
the first wet out tool 1012 and cut.
[0175] Referring now to FIGS. 11D-11F, isometric illustrations of
the first and second wet out tools 1012 and 1016 are presented. An
actuating system 1160 may be included with the second wet out tool
1016. The actuating system 1160 may include one or more linear
actuators, such as actuator 1164. The actuator 1164 can be actuated
to extend and retract the second wet out tool 1016. For example
only, the actuator 1164 may be hydraulically actuated, electrically
actuated, or actuated in another suitable manner.
[0176] Extension and/or retraction of a wet out tool may be
performed to allow pieces of the weight material to be applied
individually. For example only, the second wet out tool 1016 may be
maintained in a predetermined initial position such that the second
piece 1056 of the weight material is not applied while the first
piece 1044 of the weight material is being applied. An example of
the second wet out tool 1016 in a predetermined initial position is
presented in the example of FIG. 11D.
[0177] To apply the second piece 1056, the second wet out tool 1016
may be extended past the first wet out tool 1012. For example only,
the actuating system 1160 may extend the second wet out tool 1016
past the first wet out tool 1012 by a predetermined distance. The
predetermined distance may be based on a greatest possible change
in the radius over the distance between the inner plane of the
midplane and the inner plane of the lowerplane. Extending the
second wet out tool 1016 past the first wet out tool 1012 allows
the second piece 1056 to be applied independently of the first
piece 1044, which may or may not still be present on the first wet
out tool 1012. An example of the second wet out tool 1016 extended
past the first wet out tool 1012 is presented in the example of
FIG. 11E.
[0178] In various implementations, the actuating system 1160 or
another actuating system may be included with the first wet out
tool 1012. The actuating system 1160 may include one or more
additional linear actuators, such as actuator 1168 and actuator
1172. The actuator 1168 may extend and retract the first wet out
tool 1012 relative the second wet out tool 1016. The actuator 1172
may actuate to change the spacing between the first and second wet
out tools 1012 and 1016. An example illustration of the actuator
1172 extended to change the spacing between the first and second
wet out tools 1012 and 1016 is presented in the example of FIG.
11F. The spacing between the first and second wet out tools 1012
and 1016 may be changed, for example, in situations where the EOAT
may come into contact with the mounting surface of a wheel in
during an attempt to align the first wet out tool 1012 with the
curbside plane of the wheel.
[0179] Referring now to FIG. 11G, an example cross-sectional
illustration of the first wet out tool 1012 is presented. As stated
above, the first wet out tool 1012 may be made of a urethane or
another suitable material that provides a suitable amount of
elasticity. In various implementations, such as the example of FIG.
11G, flexible structures may provide additional compliance. In such
implementations, the first wet out tool 1012 may be made of another
suitable material that is less elastic than urethane. One or more
flexible members (e.g., coil springs) may be provided with the
first wet out tool 1012 to enable the first wet out tool 1012 to
accommodate the maximum possible change in the wheel radius.
[0180] The first wet out tool 1012 may be secured to arm and EOAT
616 via a securing assembly 1176. For example only, the securing
assembly 1176 may include a fastener 1178 (e.g., a threaded bolt),
a sleeve 1180, a bushing 1182, and a compressible washer 1184. An
inner portion of the sleeve 1180 may be tapered radially inwardly
toward the fastener 1178 from ends of the sleeve 1180. For example
only, a cross-section of the sleeve 1180 may have a butterfly shape
as illustrated in the example of FIG. 11G. The bushing 1182 is
implemented concentrically within the sleeve 1180. The fastener
1178 extends through a lateral face 1186 of the first wet out tool
1012, the bushing 1182, and a lateral face 1188 of the EOAT to
secure the first wet out tool 1012 to the EOAT. For example only,
the sleeve 1180 and the bushing 1182 may include copper.
[0181] First and second resilient members 1190 and 1192 are located
radially outwardly from the fastener 1178. The first and second
resilient members 1190 and 1192 apply a biasing force against the
lateral wall 1186 of the first wet out tool 1012. For example only,
the first and second resilient members 1190 and 1192 may each
include a ball 1194, a ball stop 1196, and a biasing source 1198.
The biasing source 1198 may bias the ball 1194 against the ball
stop 1196 where the ball 1194 will generally be in contact with the
lateral wall 1186 of the first wet out tool 1012. For example only,
the biasing source 1198 may include a spring, air, a hydraulic
fluid, or another suitable biasing member.
[0182] When the front face 1024 of the first wet out tool 1012
contacts the inner surface of a wheel where the wheel radius is
changing, the first and second resilient members 1190 and 1192
allow the first wet out tool 1012 to pivot to accommodate the
changing wheel radius. More specifically, a changing wheel radius
may force the first wet out tool 1012 to pivot and apply a force
that is greater than the biasing force to one of the balls 1194.
For example only, the first wet out tool 1012 may pivot in a first
direction 1197 and apply a force to the ball 1194 of the second
resilient member 1192. The first wet out tool may pivot in a second
direction 1198 and apply a force to the ball 1194 of the first
resilient member 1190. The application of a force to one of the
balls 1194 forces the one of the balls 1194 away from the
associated one of the ball stops 1196, thereby allowing the first
wet out tool 1012 to pivot. The tapered/butterfly shape of the
sleeve 1180 allows the bushing 1182 to pivot within the sleeve
1180.
[0183] Referring now to FIG. 12, a flowchart depicting an example
method 1200 of balancing a wheel is presented. Control begins at
1204, where control receives balancing data. For example only, the
balancing data includes the first and second offsets, the first and
second radii, the first and second angles, and the first and second
desired weights. The balancing data may also include the lengths of
the first and second pieces.
[0184] While not shown, control may determine whether either of the
first and second pieces need to be applied based on the balancing
data. If neither piece needs to be applied, such as if the weights
are zero or are below a minimum threshold, control may return to
1204 and wait for the balancing data of the next wheel to arrive.
If only the second piece needs to be applied, control may transfer
to 1224. Otherwise, control continues at 1208.
[0185] At 1208, the cutting apparatus 106 dispenses the first piece
1044 of the weight material past the cutting apparatus edge 924.
The first piece 1044 of the weight material corresponds to the
desired weight to be applied within the midplane of the wheel, with
the midpoint of the first piece 1044 being located at the first
angle. The first piece 1044 is dispensed while the first wet out
tool 1012 is away from the cutting position. If the first piece
1044 was dispensed while the first wet out tool 1012 was in the
cutting position or the final cutting position, the magnetic force
of the magnetic devices 1130 may cause the first piece 1044 to lay
undesirably upon the arc shaped face 1024 of the first wet out tool
1012. For example only, the first piece 1044 may not lay flatly
upon the arc shaped face 1024.
[0186] At 1212, control moves the first wet out tool 1012 into the
final cutting position. For example only, the leading edge 1024 of
the first wet out tool 1012 may first be moved to the cutting
position at the predetermined distance away from the cutting
apparatus edge 924. Second, control may rotate the first wet out
tool 1012 about the leading edge 1024 to position the first wet out
tool 1012 in the final cutting position. Moving the first wet out
tool 1012 into the final cutting position in this manner may allow
the first piece 1044 of the weight material to be drawn towards the
magnetic devices 1130 of the first wet out tool such that the first
piece 1044 lays flatly along the arc shaped face 1024 of the first
wet out tool 1012 between the first and second flanges 1112 and
1116.
[0187] Alternatively, the first wet out tool 1012 could be moved
into position prior to the first piece 1044 of the weight material
being dispensed. If the weight material has adequate rigidity, the
first piece 1044 may slide along the face 1024 of the first wet out
tool 1012, without arching (i.e., creating a gap between the first
piece 1044 and the face 1024 of the first wet out tool 1012). This
approach may require less time, as the first wet out tool 1012 can
be moved directly to the dispense location instead of being moved
and then rotated into place.
[0188] At 1216, the cutting apparatus 106 cuts the first piece 1044
from the strip 102. More specifically, the blade 210 is lowered to
cut the first piece 1044 using the slit that is defined by the
cutting apparatus edge 924 and the leading edge 1024 of the first
wet out tool 1012. The EOAT 1008 may be moved away from the cutting
position so the second piece 1056 can be dispensed at 1220.
[0189] While not shown, control may determine the second piece is
to be applied based on the balancing data. If true, control may
proceed with 1224; if false, control may proceed to 1236, which is
discussed further below. The second piece 1056 of the weight
material is dispensed past the cutting apparatus edge 924 at 1224.
At 1228, the second wet out tool 1016 is moved into the final
cutting position. For example only, the leading edge 1032 of the
second wet out tool 1016 may first be moved to the cutting position
at the predetermined distance away from the cutting apparatus edge
924. Second, control may rotate the second wet out tool 1016 about
the leading edge 1032 to position the second wet out tool 1016 in
the final cutting position. The second wet out tool 1016 may be
moved in a path that is similar or identical to the path taken in
moving the first wet out tool 1012 into the final cutting position.
Alternatively, the second wet out tool 1016 may be moved to the
final cutting position prior to dispensing of the second piece 1056
of wheel weight material.
[0190] The second piece 1056 is cut using the slit defined by the
cutting apparatus edge 924 and the leading edge 1032 of the second
wet out tool 1016 at 1232. At 1236, control may determine a path to
take in applying the first and/or second pieces 1044 and 1056.
Control may determine the path based on the first and second
offsets, the first and second angles, and the first and second
radii. Control may determine the path further based on the
reference angle, the mounting plane, the reference axis, and/or one
or more other suitable parameters.
[0191] At 1240, control actuates the arm 1004 based on the path to
position the leading edge 1020 of the first wet out tool 1012 at a
first desired angle and to position the arc shaped face 1024 of the
first wet out tool 1012 within the midplane of the wheel. The first
desired angle corresponds to the angle at which the newly cut edge
of the first piece 1044 should begin such that the midpoint of the
first piece 1044 is applied at the first angle. While not shown,
control may determine whether the first piece is present on the
first wet out tool 1012. If true, control may proceed with 1244; if
false, control may proceed to 1248, which is discussed further
below.
[0192] Control actuates the arm 1004 to apply the first piece 1044
in a rolling motion, from the leading edge 1020 toward the trailing
edge 1028 at 1244. Applying a piece in the rolling motion may be
referred to as wetting out the piece. Wetting out may be defined as
applying the piece such that the adhesive on the piece flows to
create a maximum contact area between the adhesive and the bonding
surface, thereby maximizing the attractive forces between the
adhesive and the bonding surface. Control actuates the arm 1004 to
apply the first piece 1044 at a predetermined pressure at 1244. For
example only, the predetermined pressure may be approximately 15
pounds per square inch (PSI).
[0193] By applying the first piece 1044 in the rolling motion, the
partial circle (i.e., arc) shape of the arc shaped face 1024
ensures that the adhesive surface of the first piece 1044 contacts
the wheel as much as possible. The rolling motion may be from the
leading edge 1020 to the trailing edge 1028 or from the leading
edge 1020 to a point on the arc shaped face 1024 between the
leading and trailing edges 1020 and 1028. For example only, the
point may be a point on the arc shaped face 1024 between the
trailing edge 1028 and the previously cut end 1048 of the first
piece 1044.
[0194] While not shown, control may determine whether the second
piece is present on the second wet out tool 1016. If true, control
may proceed with 1248; if false, control may end and start over
when balancing data is received for a next wheel.
[0195] Control extends the second wet out tool at 1248 to
accommodate the maximum possible change in the radius of the wheel.
Control extends the second wet out tool 1016 past the first wet out
tool 1012. After the first piece 1044 is applied to the wheel,
control may move the EOAT 1008 including the first and second wet
out tools 1012 and 1016 away from the interior surface of the wheel
before extending the second wet out tool 1016 as to not
inadvertently apply the second piece 1056 of the weight
material.
[0196] Control actuates the arm 1004 based on the path to position
the leading edge 1032 of the second wet out tool 1016 at a second
desired angle and to position the arc shaped face 1036 of the
second wet out tool 1016 within with the lowerplane of the wheel at
1252. The second desired angle corresponds to the angle at which
the newly cut edge of the second piece 1056 should begin such that
the midpoint of the second piece 1056 is applied at the second
angle. Control actuates the arm 1004 to apply the second piece 1056
in the rolling motion, from the leading edge 1036 toward the
trailing edge 1040 at 1256. Control actuates the arm 1004 to apply
the second piece 1056 at the predetermined pressure. Control may
then end.
[0197] Referring now to FIG. 13, a functional block diagram of an
example control system 1300 of the arm 1004 and the EOAT 1008 is
presented. A central control module 1304 may receive the balancing
data for a wheel from a balancing data module 1308. More
specifically, the central control module 1304 may receive the first
and second offsets, the first and second radii, and the first and
second angles. The central control module 1304 may also receive the
desired weights of the first and second pieces and/or the lengths
of the first and second pieces.
[0198] The balancing data module 1308 may receive the first and
second offsets, radii, and angles from the balancer 608. For
example only, the balancing data module 1308 may receive the
balancing data over a serial interface, a parallel interface, a
factory control network, a local area network, or a direct
electrical interface. For example only, support and communication
protocols may include Ethernet, data highway plus (DH plus),
controller area network (CAN), and DeviceNet. In various
implementations, the balancing data may be transferred to the
balancing data module 1308 via another mechanism, such as by a
conveyer control system, an upper-level system, a plant management
system, and/or a data tracking system.
[0199] In various implementations, the balancing data module 1308
may include a conversion front end (not shown) and a reference
interface, such as RS-232. The conversion front end converts an
incoming interface to the reference interface. In this way, the
conversion front end can be replaced when a new external interface
is used, while retaining RS-232 for internal communication. In
various implementations, the balancing data may be provided to the
balancing data module 1308 via another suitable input source, such
as a user.
[0200] A reference data module 1312 may provide the reference data
to the central control module 1304. The reference data may include,
for example, the distance between the mounting plane and a plane
upon which the wheel rests, the reference angle, the reference
axis, and/or one or more other suitable pieces of reference data.
The plane upon which the wheel rests may be referred to as a
reference plane.
[0201] In various implementations, the reference data may be
predetermined data. In various other implementations, one or more
pieces of the reference data may be provided by another apparatus.
For example only, the distance between the reference plane and the
mounting plane of the wheel may be determined and provided to the
reference data module 1312 by a mounting plane learning system,
described below.
[0202] The reference data module 1312 may store data corresponding
to each combination of wheel and tire that has been or is expected
to be balanced. For a given combination of wheel and tire, the
physical characteristics, such as wheel geometry and location of
the mounting plane, should be fixed. The wheel geometry includes
radii, offsets of planes (including midplane and lowerplane) from
the mounting plane, and clearance for maneuvering the robotic arm.
The wheel geometry may be determined from the wheel blueprints
during installation and pre-programmed into the reference data
module 1312. As new wheel types are introduced, the reference data
module 1312 can be updated with their characteristics.
[0203] The wheel geometry may be independent of the tire mounted to
the wheel. However, one parameter that may change depending on
selected tire, and even depending on level of inflation of the
tire, is the absolute location of the mounting plane. When the
wheel and tire combination is resting on a conveyor belt, the tire
may lift the wheel higher than if the wheel alone were resting on
the conveyor belt. Because generally all wheel geometry is
referenced to the mounting plane, the position of the mounting
plane should be determined so that balancing weights can be placed
accurately.
[0204] Assuming that the robotic arm is mounted to a fixed position
below the conveyor belt, the vertical position of the conveyor belt
with respect to the robotic arm mount is fixed and can be
pre-programmed. Then, if the vertical distance between the conveyor
belt and the mounting plane can be determined, the absolute
position of the mounting plane can be calculated. In various
implementations, the amount that the tire lifts the wheel off the
conveyor belt may be calculated or measured. Inflation pressure of
tires may be standardized, and in some cases, variations in the
inflation pressure may result in only negligible changes in how
high the wheel is lifted.
[0205] Another approach, an example of which is described below in
FIG. 14, involves physically measuring the height of the mounting
plane, using either the robotic arm or a separate height measuring
device. Once the height of the mounting plane is determined or
measured for a given wheel and tire combination, that height can be
stored, and relied on for each future balancing of that wheel and
tired combination. In various implementations, the height may be
checked at periodic intervals, such as after a predetermined number
of wheels having been balanced, or after a predetermined period of
time.
[0206] Referring now to FIG. 14, an isometric view of an example
implementation of a mounting plane learning system 1400 is
presented. A distance learning apparatus 1404 may be used in
conjunction with and/or implemented with the arm 1004 and the EOAT
1008. The distance learning apparatus 1404 may be used to determine
the distance between a reference plane 1410 and the mounting plane
714.
[0207] In various implementations, the distance learning apparatus
1404 may include a pressure switch and a plate implemented on the
EOAT 1008. The EOAT 1008 may be extended through the opening 816
with the pressure switch/plate parallel to the mounting surface
712. When the pressure switch is actuated due to contact with the
mounting surface 712 of the wheel, the distance between the
reference plane 1410 and the mounting plane 714 may be determined.
For example only, the distance between the reference plane 1410 and
the mounting plane 714 may be determined based on a known location
of the reference plane 1410 and how far the distance learning
apparatus 1404 had moved past the reference plane 1410 when the
pressure switch is actuated.
[0208] In various implementations, the distance learning apparatus
1404 may be implemented independently of the EOAT, such as on
another robotic arm or simply on a piston. The piston may have to
be a multi-stage nested piston to reach the mounting plate while
still being able to retract below the surface of the conveyor belt.
The distance learning apparatus 1404 may include one or more types
of distance learning devices, such as a linear variable distance
transducer (LVDT) that determines the distance between the
reference plane 1410 and the mounting plane 714. For example only,
the LVDT may be calibrated based on a value of zero when the LVDT
is at the reference plane 1410.
[0209] The LVDT may extend through the opening 816, past the
reference plane 1410, until the LVDT makes contact with the
mounting surface 712. When the LVDT contacts the mounting surface
712, the distance between the reference plane 1410 and the mounting
plane 714 may be determined based on how far the LVDT extended past
the reference plane 1410. In various implementations, the distance
learning apparatus 1404 may include a linear quadrature encoder
and/or an optical measuring system (e.g., a laser measuring
system), and/or another suitable apparatus that determines the
distance between the reference plane 1410 and the mounting plane
714.
[0210] The distance learning apparatus 1404 may be actuated into
the opening 816 through which the weight material is applied to the
interior surface of the wheel or below the opening 816 when the arm
1004 and the EOAT 1008 are clear of the opening 816. For example
only, the distance learning apparatus 1404 may be used to determine
the distance while the first and second pieces 1044 and 1056 are
being cut.
[0211] The distance learning apparatus 1404 may be employed to
determine the distance between the reference plane 1410 and the
mounting plane 714 selectively. For example only, the distance
learning apparatus 1404 may be used to determine a value of the
distance between the reference plane 1410 and the mounting plane
714 one or more times for a given type of wheel and tire
combination.
[0212] The distance learning apparatus 1404 may thereafter be used
periodically to verify and/or update the value of the distance
while the same type of wheel is being balanced. Using the distance
learning apparatus 1404 periodically when one type of wheel is
being balanced may increase throughput (i.e., the number of wheels
balanced per unit time) while still ensuring accurate placement of
the wheel weight material.
[0213] In various implementations, the distance between the
reference plane 1410 and the mounting plane 714 may be a
predetermined distance. The predetermined distance may be set based
on the distance between the carside plane 1414 of the wheel and the
mounting plane 714. The distance between the carside plane 1414 and
the mounting plane 714 may be provided by, for example, a wheel
manufacturer, the balancer 608, or another suitable source of the
characteristics of the wheel.
[0214] However, a tire mounted on the wheel may cause the carside
plane 1414 of the wheel to sit above the reference plane 1410.
Bulging 1418 of the tire may cause the carside plane 1414 of the
wheel to be different than the reference plane 1410. Accordingly,
if the predetermined distance is set to the distance between the
carside plane 1414 and the mounting plane 714, the predetermined
distance may be inaccurate by an amount approximately equal to the
height of the bulge 1418. In some implementations, this amount may
be negligible or may be mitigated by adjusting (i.e., increasing)
the predetermined distance by a predetermined amount. The
predetermined amount may be set based on half of the height of the
bulge 1418 in various implementations. In various implementations,
the height of the bulge 1418 may be estimated, previously
determined or measured, estimated, etc.
[0215] Referring back to FIG. 13, a path determination module 1316
determines a path for receiving and cutting the first and second
pieces 1044 and 1056 using the EOAT 1008. An example path is
described above in conjunction with FIGS. 10A-10H. An arm actuator
control module 1318 selectively controls movement of the arm 1004
based on the path.
[0216] A material detection module 1320 may indicate to the central
control module 1304 when a piece of the weight material is present
on a wet out tool. A cutter interfacing module 1324 may communicate
with the central control module 302 to coordinate the operation of
the cutting apparatus 106 with the operation of the arm 1004 and
the EOAT 1008.
[0217] For example only, the central control module 302 may wait
for an EOAT clear signal from the cutter interfacing module 1324
before dispensing the first piece 1044 of the weight material for
cutting. The central control module 1304 may generate the EOAT
clear signal when the EOAT is away from the cutting apparatus edge
924 such that dispensed material will not contact or be drawn into
contact with a wet out tool. The central control module 302 may
transmit a first material dispensed signal to the central control
module 1304 when the first piece of material has been dispensed for
cutting.
[0218] After receiving the first material dispensed signal, the
central control module 1304 may actuate the arm 1004 to follow the
path determined by the path determination module 1316. The path may
include first bringing the leading edge 1024 of the first wet out
tool 1012 into the cutting position and, second, rotating the first
wet out tool 1012 up about the leading edge 1024 to position the
first wet out tool 1012 in the final cutting position. In
implementations where the magnetic devices 1130 are electromagnetic
devices, a magnet control module 1328 may control the operation of
the magnetic devices 1130. For example only, the central control
module 1304 may operate the magnetic devices 1130 after the first
material dispensed signal is received. The central control module
1304 may selectively disable the magnetic devices 1130 after one or
more of the first and second weights 1040 and 1056 have been
applied.
[0219] The central control module 302 may wait to receive a cut
signal from the cutter interfacing module 1324 before cutting the
first piece 1044 from the strip 102. The central control module
1304 may generate the cut signal once the first wet out tool 1012
is in the final cut position. The cutter apparatus 106 cuts the
first piece 1044 of the weight material from the strip 102 in
response to the cut signal.
[0220] After moving the EOAT 1008 away from the cutting apparatus
edge 924, the central control module 1304 may determine whether the
first piece 1044 is present on the first wet out tool 1012. For
example only, the material detection module 1320 may indicate that
the first piece 1044 is present on the first wet out tool 1012 when
the presence of the first piece 1044 is detected based on the
signals generated by the one or more presence detection sensors
implemented with the first wet out tool 1012. The first piece 1044
not being present after the EOAT 1044 has been moved away from the
cutting apparatus edge 924 may indicate that the first piece 1044
slid off of the first wet out tool 1012, that the first piece 1044
was not cut as expected, and/or that one or more other faults may
be present. For example only, the first piece 1044 not being
present may indicate that the blade 210 is dull and should be
replaced. The cutting apparatus 106 and/or the central control
module 1304 may take one or more remedial actions accordingly.
[0221] The central control module 1304 may (for a second time for
the wheel) transmit the EOAT clear signal to the central control
module 302 once the EOAT is moved away from the cutting apparatus
edge 924. The central control module 302 may dispense the second
piece 1056 of the weight material for cutting when the EOAT clear
signal is received. The central control module 302 may transmit a
second material dispensed signal to the central control module 1304
once the second piece 1056 has been dispensed for cutting.
[0222] After the second material dispensed signal is received, the
central control module 1304 may actuate the arm 1004 to follow the
path determined by the path determination module 1316. The path may
include first bringing the leading edge 1032 of the second wet out
tool 1016 into the cutting position and, second, rotating the
second wet out tool 1016 up about the leading edge 1032 to position
the second wet out tool 1016 in the final cutting position.
[0223] The central control module 302 may wait to receive the cut
signal (for a second time for the wheel) from the cutter
interfacing module 1324 before cutting the second piece 1056 from
the strip 102. The central control module 1304 may generate the cut
signal when the second wet out tool 1016 is in the final cut
position. The cutter apparatus 106 cuts the second piece 1056 of
the weight material from the strip 102 in response to the cut
signal.
[0224] After moving the EOAT 1008 away from the cutting apparatus
edge 924 again, the central control module 1304 may determine
whether the second piece 1056 is present on the second wet out tool
1016. For example only, the material detection module 1320 may
indicate that the second piece 1056 is present on the second wet
out tool 1016 when the presence of the second piece 1056 is
detected based on the signals generated by the one or more presence
detection sensors implemented with the second wet out tool
1016.
[0225] The path determination module 1316 also determines the path
to follow in applying the first and second pieces 1044 and 1056 to
the wheel. The path determination module 1316 may determine the
path based on the first and second offsets, the first and second
radii, and the first and second angles. The path determination
module 1316 may determine the path further based on one or more
pieces of the reference data and/or other suitable data.
[0226] The path may include first moving the EOAT 1008 to the
reference axis. Once there, the arm actuator control module 1318
may position the leading edge 1020 of the first wet out tool 1012
at the first desired angle and position an edge of the arc shaped
face 1024 at the first offset and the first radius within the
midplane of the wheel.
[0227] A desired angle determination module 1318 may determine the
first and second desired angles based on the reference angle, the
first and second angles, the length of the first and second pieces,
respectively, and/or other suitable data. For example only, the
desired angle determination module 1318 may determine an angular
distance within the midplane that corresponds to half of the length
of the first piece. The desired angle determination module 1318 may
set the first desired angle by adjusting the first angle toward the
reference angle by the angular distance. Similarly, the desired
angle determination module 1318 may determine the second desired
angle based on an angular distance within the lowerplane
corresponding to half of the length of the second piece and set the
second desired angle by adjusting the second dangle toward the
reference angle by the angular distance.
[0228] Before applying the first and/or second weights 1044 and
1056 (e.g., before positioning the EOAT 1008 within the wheel
cavity), the central control module 1304 may wait for a crowder
done signal from the crowder 624. The central control module 1304
may communicate with the crowder 624 via a crowder interfacing
module 1330. The crowder 624 may transmit the crowder done signal
to the central control module 1304 when the crowder 624 has
centered the wheel about the reference axis and the crowder 624 is
holding the wheel (and/or tire).
[0229] An EOAT actuator control module 1334 controls extension and
retraction of the second wet out tool 1016. Prior to the
application of the first piece 1044, the EOAT actuator control
module 1334 may retract the second wet out tool 1056 to a
predetermined initial position. When in the predetermined initial
position, the second wet out tool 1016 may be retracted with
respect to the first wet out tool 1012 or aligned with the first
wet out tool 1012. The retraction of the second wet out tool 1016
to the predetermined position may prevent the second piece 1056
from inadvertently being applied without being first correctly
positioned.
[0230] The arm actuator control module 1318 applies the first piece
1044 starting at the leading edge 1020 of the first wet out tool
1012 (which is positioned at the first desired angle) and rolling
the first wet out tool 1012 toward the trailing edge 1028 of the
first wet out tool 1012. The arm actuator control module 1318
applies the first piece 1044 in the rolling motion at the
predetermined pressure. The arm actuator control module 1318 may
roll the first wet out tool 1012 all the way to the trailing edge
1028 of the first wet out tool 1012 or to a location between the
trailing edge 1028 and the previously cut end 1048 of the first
piece 1044.
[0231] The EOAT actuator control module 1334 may extend the second
wet out tool 1016 to a predetermined extended position after the
first piece 1044 is applied. For example only, the EOAT actuator
control module 1334 may extend the second wet out tool 1016 while
the EOAT is moved toward the second desired angle, offset, and
radius. When in the predetermined extended position, the arc shaped
face 1036 of the second wet out tool 1016 is extended past the arc
shaped face 1024 of the first wet out tool 1012. The predetermined
extended position may be a predetermined distance past the position
of the first wet out tool 1012. The predetermined distance may be
based on the maximum possible change in the radius of the wheel
over the distance between the first and second wet out tools 1012
and 1016.
[0232] Once the second wet out tool 1016 is extended, the arm
actuator control module 1318 positions the leading edge 1032 of the
second wet out tool 1016 at the second desired angle and positions
the arc shaped face 1036 of the second wet out tool 1016 within the
lowerplane of the wheel. The arm actuator control module 1318
applies the second piece 1056 starting at the leading edge 1032 of
the second wet out tool 1016. The arm actuator control module 1318
rolls the second wet out tool 1016 from the leading edge 1032
toward the trailing edge 1040 of the second wet out tool 1016. The
arm actuator control module 1318 applies the second piece 1056 in
the rolling motion at the predetermined pressure. The arm actuator
control module 1318 may roll the second wet out tool 1016 all the
way to the trailing edge 1040 of the second wet out tool 1016 or to
a location between the trailing edge 1040 and the previously cut
end 1060 of the second piece 1056. The second piece 1056 may be
applied by rolling the second wet out tool 1016 similar to how the
first piece 1044 is applied. The rolling motion wets out the
pieces.
[0233] Referring now to FIGS. 15A-15B, a flowchart depicting an
example method 1600 of controlling the arm 1004 and the EOAT 1008
is presented. Control begins at 1604, where balancing data is
received. At 1608, control determines, based on the balancing data,
whether application of a first piece is necessary. If so, control
continues at 1612; otherwise, control transfers to 1616.
[0234] At 1612, controls positions the first wet out tool in the
final cutting position. Control continues at 1620, where a dispense
and cut signal is sent to the cutting system, such as the central
control module 302 of FIG. 3. Control continues at 1624 and waits
until a done signal is received before proceeding to 1628. At 1628,
control determines whether the first piece 1044 is present on the
first wet out tool 1012 based on feedback received from the one or
more sensors implemented with the first wet out tool 1012. If the
piece is present, control transfers to 1616; otherwise, control
transfers to 1632.
[0235] At 1632, control performs error handling. This may stop the
automated balancing process and wait for operator intervention.
Alternatively, the robot may initiate a cleaning process, such as
wiping the face of the EOAT on an absorbent blotting material to
remove accumulated grease or other lubricating elements. Control
may then request the piece to be re-cut at 1636, and control
returns to 1624. When the error handling 1632 is reached
frequently, such as more than twice during a predetermined
timeframe, balancing may be halted until an operator reviews the
problem and affirmatively restarts the balancing process.
[0236] At 1616, control determines whether the second piece is
required. If so, control continues at 1640; otherwise, control
returns to 1604. At 1640, control moves the second wet out tool
into the final cutting position. Control continues at 1644, where
the dispense and cut signal is sent to the cutting system. Control
continues at 1648 and waits until a done signal is received before
continuing at 1652. At 1652, control determines whether the second
piece 1056 is present on the second wet out tool 1016. If so,
control continues to FIG. 15B; otherwise, control transfers to
1656. At 1656, control performs error handling. Once the error has
been addressed and/or logged, control transmits a cut again signal
to the cutting system at 1660. Control then returns to 1648.
[0237] At 1682 (FIG. 15B), control may determine the path for
applying the first and second pieces 1044 and 1056. Control may
follow the path to position the leading edge 1020 of the first wet
out tool 1012 at the first desired angle and to position the arc
shaped face 1024 of the first wet out tool 1012 within the midplane
at 1686. Control may also retract the second wet out tool 1016 at
1686. Control applies the first piece 1044 by rolling the first wet
out tool 1012 along the midplane of the wheel from the leading edge
1020 toward the trailing edge 1028 of the first wet out tool 1012
at the predetermined pressure at 1686.
[0238] Once the first piece 1044 has been applied, control extends
the second wet out tool 1016 to the predetermined extended position
at 1692. Control may follow the path to position the leading edge
1032 of the second wet out tool 1016 at the second desired angle
and to position the arc shaped face 1036 of the second wet out tool
1016 within the lowerplane at 1694. In various implementations,
control may extend the second wet out tool 1016 while control is
moving the second wet out tool 1016 into position at 1694. Control
applies the second piece 1056 by rolling the second wet out tool
1016 along the lowerplane of the wheel from the leading edge 1032
toward the trailing edge 1040 of the second wet out tool 1016 at
the predetermined pressure at 1696. Control then returns to 1604 of
FIG. 15A.
[0239] The broad teachings of the disclosure can be implemented in
a variety of forms. Therefore, while this disclosure includes
particular examples, the true scope of the disclosure should not be
so limited since other modifications will become apparent to the
skilled practitioner upon a study of the drawings, the
specification, and the following claims.
* * * * *