U.S. patent application number 17/106806 was filed with the patent office on 2021-03-18 for multi-speed power tool with electronic clutch.
The applicant listed for this patent is MILWAUKEE ELECTRIC TOOL CORPORATION. Invention is credited to Cole Conrad, Daniel Robert Ertl, Alex Huber, Mark Alan Kubale, Matthew Mergener, Carl Benjamin Westerby, Matthew Wycklendt, Wing Fung Yip.
Application Number | 20210078151 17/106806 |
Document ID | / |
Family ID | 1000005248305 |
Filed Date | 2021-03-18 |
United States Patent
Application |
20210078151 |
Kind Code |
A1 |
Huber; Alex ; et
al. |
March 18, 2021 |
MULTI-SPEED POWER TOOL WITH ELECTRONIC CLUTCH
Abstract
A power tool and a method of operating a power tool including a
motor, a clutch collar including a plurality of settings, a
wireless transceiver operable to form a wireless connection with a
remote device, and a processor coupled to the clutch collar and the
wireless transceiver. The processor receives, via the wireless
transceiver, a mapping including a plurality of torque levels
corresponding to the plurality of settings. The processor detects
that the clutch collar is set to a setting of the plurality of
settings. The processor is further determines the torque level for
the setting from the mapping and detects, during the operation of
the power tool, that a torque of the power tool exceeds the torque
level. The processor is also configured to generate an indication
that the torque exceeds the torque level. The indication may
include flashing a light, ratcheting the motor, and stopping the
motor.
Inventors: |
Huber; Alex; (Milwaukee,
WI) ; Westerby; Carl Benjamin; (Milwaukee, WI)
; Ertl; Daniel Robert; (Brookfield, WI) ;
Wycklendt; Matthew; (Madison, WI) ; Mergener;
Matthew; (Mequon, WI) ; Kubale; Mark Alan;
(West Bend, WI) ; Conrad; Cole; (Wauwatosa,
WI) ; Yip; Wing Fung; (Kowloon, HK) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MILWAUKEE ELECTRIC TOOL CORPORATION |
Brookfield |
WI |
US |
|
|
Family ID: |
1000005248305 |
Appl. No.: |
17/106806 |
Filed: |
November 30, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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15146547 |
May 4, 2016 |
10850380 |
|
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17106806 |
|
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|
62180586 |
Jun 16, 2015 |
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62169671 |
Jun 2, 2015 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F16D 2500/3027 20130101;
F16D 2500/7102 20130101; B25D 16/006 20130101; B25D 16/003
20130101; F16D 2500/30426 20130101; F16D 2500/7104 20130101; F16D
48/06 20130101; F16D 2500/51 20130101; F16D 2500/7103 20130101;
F16D 2500/10418 20130101; B25D 2250/165 20130101; B25D 2250/205
20130101; B25F 5/001 20130101; B25D 2250/221 20130101; F16D
2500/7101 20130101; F16D 2500/30415 20130101; F16D 2500/3022
20130101 |
International
Class: |
B25D 16/00 20060101
B25D016/00; F16D 48/06 20060101 F16D048/06; B25F 5/00 20060101
B25F005/00 |
Claims
1. A power tool comprising: a housing; a motor within the housing;
a wireless transceiver operable to form a wireless connection with
a remote device; and a processor connected to the wireless
transceiver, the processor configured to: receive, via the wireless
transceiver, a torque level from the remote device, detect, during
operation of the power tool, that a torque of the power tool
exceeds the torque level, and generate an indication that the
torque exceeds the torque level.
2. The power tool of claim 1, further comprising a current sensor
connected to the processor, wherein the processor is configured to
detect the torque based on a motor current sensed by the current
sensor.
3. The power tool of claim 1, wherein the indication includes at
least one selected from the group consisting of flashing a light,
ratcheting the motor, and stopping the motor.
4. The power tool of claim 1, wherein the indication includes
ratcheting the motor, and an intensity of the ratcheting is set by
the processor based on the torque level.
5. The power tool of claim 1, wherein the torque level is provided
as a fixed magnitude of torque.
6. The power tool of claim 1, wherein the torque level is provided
as a percentage of available torque.
7. The power tool of claim 1, wherein the processor is further
configured to: receive, via the wireless transceiver, a request to
enable an anti-kickback feature; receive, via the wireless
transceiver, an anti-kickback level for the anti-kickback feature;
set the anti-kickback torque level; detect, during operation of the
power tool, that the torque of the power tool exceeds the
anti-kickback torque level; and stop the motor when the torque
exceeds the anti-kickback torque level.
8. The power of claim 1, wherein the torque level is a first torque
level provided for a first mode, the power tool further comprising:
a mode selector configured to select between the first mode and a
second mode; the electronic processor is further configured to:
receive, via the wireless transceiver, a second torque level from
the remote device for the second mode, receive, using the mode
selector, a selection of the second mode, detect, during operation
of the power tool, that the torque of the power tool exceeds the
second torque level, and generate an indication that the torque
exceeds the second torque level.
9. A method of operating a power tool including a housing and a
motor within the housing, the method comprising: receiving, with a
processor via a wireless transceiver of the power tool, a torque
level from a remote device; detecting, with the processor, that a
torque of the power tool exceeds the torque level during operation
of the power tool; and generating, with the processor, an
indication that the torque exceeds the torque level.
10. The method of claim 9, wherein detecting the torque includes
detecting a motor current and calculating an estimated torque based
on the motor current.
11. The method of claim 9, wherein the indication includes
ratcheting the motor, and an intensity of the ratcheting varies
with the torque level.
12. The method of claim 9, wherein the indication includes at least
one selected from the group consisting of flashing a light,
ratcheting the motor, and stopping the motor.
13. The method of claim 9, wherein the torque level is provided as
a fixed magnitude of torque.
14. The method of claim 9, wherein the torque level is provided as
a percentage of available torque.
15. The method of claim 9, further comprising: receiving, via the
wireless transceiver, a request to enable an anti-kickback feature;
receiving, via the wireless transceiver, an anti-kickback level for
the anti-kickback feature; setting, with the processor, the
anti-kickback torque level; detecting, with the processor during
operation of the power tool, that the torque of the power tool
exceeds the anti-kickback torque level; and stopping, with the
processor, the motor when the torque exceeds the anti-kickback
torque level.
16. The method of claim 9, wherein the torque level is a first
torque level provided for a first mode, the method further
comprising: receiving, with the processor via the wireless
transceiver, a second torque level from the remote device for a
second mode; receiving, using a mode selector for selecting between
the first mode and the second mode, a selection of the second mode;
detecting, with the processor, that the torque of the power tool
exceeds the second torque level during operation of the power tool;
and generating, with the processor, an indication that the torque
exceeds the second torque level.
17. A power tool comprising: a housing; a motor within the housing;
a wireless transceiver operable to form a wireless connection with
a remote device; and a processor connected to the wireless
transceiver, the processor configured to: receive, via the wireless
transceiver, a plurality of torque levels for a plurality of
operating modes from the remote device, determine that the power
tool is operating in a first mode of the plurality of operating
modes; detect, during operation of the power tool, that a torque of
the power tool exceeds a first torque level of the plurality of
torque levels corresponding to the first mode, and generate an
indication that the torque exceeds the first torque level.
18. The power tool of claim 17, wherein the electronic processor is
further configured to: determine that the power tool is operating
in a second mode of the plurality of operating modes; detect,
during operation of the power tool, that the torque of the power
tool exceeds a second torque level of the plurality of torque
levels corresponding to the second mode; and generate a second
indication that the torque exceeds the second torque level.
19. The power tool of claim 17, further comprising a current sensor
connected to the processor, wherein the processor is configured to
detect the torque based on a motor current sensed by the current
sensor.
20. The power tool of claim 17, wherein the indication includes at
least one selected from the group consisting of flashing a light,
ratcheting the motor, and stopping the motor.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/146,547, filed on May 4, 2016, now U.S.
Pat. No. 10,850,380, which claims priority to U.S. Provisional
Patent Application No. 62/169,671, filed on Jun. 2, 2015, and U.S.
Provisional Patent Application No. 62/180,586, filed on Jun. 16,
2015, the entire contents of which are hereby incorporated by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to an electronic clutch for a
power tool.
SUMMARY
[0003] One embodiment provides a power tool including a housing, a
motor within the housing, a clutch collar on the housing including
a plurality of settings, a wireless transceiver operable to form a
wireless connection with a remote device, and a processor coupled
to the clutch collar and the wireless transceiver. The processor is
configured to receive, via the wireless transceiver, a mapping
including a plurality of torque levels corresponding to the
plurality of settings and detect that the clutch collar is set to a
setting of the plurality of settings. The processor is further
configured to determine the torque level for the setting from the
mapping and detect, during the operation of the power tool, that a
torque of the power tool exceeds the torque level. The processor is
also configured to generate an indication that the torque exceeds
the torque level.
[0004] Another embodiment provides a method of operating a power
tool including a housing, a motor within the housing, a clutch
collar on the housing including a plurality of settings, and an
electronic clutch. The method includes receiving, with a processor
via a wireless transceiver, a mapping including a plurality of
torque levels corresponding to the plurality of settings and
detecting, with the processor, that the clutch collar is set to a
setting from the plurality of settings. The method also includes
determining, with the processor, the torque level for the setting
from the mapping, and detecting, with the processor, that a torque
of the power tool exceeds the torque level during operation of the
power tool. The method further includes generating, with the
processor, an indication that the torque exceeds the torque
level.
[0005] Another embodiment provides a method of operating a housing,
a motor within the housing, a clutch collar on the housing
including a plurality of settings, and an electronic clutch. The
method includes receiving, with a processor via a wireless
transceiver, a first torque value generated by a remote device
based on user input and wirelessly transmitted by the remote device
to the wireless transceiver. The method further includes the
processor detecting that the clutch collar is set to a setting of
the plurality of settings. The processor calculates a torque level
for the setting based on the position of the setting among the
plurality of settings and the first torque value. The method
further includes controlling the motor based on the torque
level.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIGS. 1A and 1B illustrate a power tool according to some
embodiments.
[0007] FIG. 2 illustrates a block diagram of the power tool
according to some embodiments.
[0008] FIGS. 3A and 3B illustrate a printed circuit board assembly
associated with the power tool of FIGS. 1A and 1B according to some
embodiments.
[0009] FIG. 4 illustrates a circuit diagram of the printed circuit
board assembly of FIGS. 3A and 3B according to some
embodiments.
[0010] FIG. 5 illustrates a block diagram of a remote device
according to some embodiments.
[0011] FIGS. 6A and 6B illustrate a graphical user interface of a
remote device associated with the power tool of FIGS. 1A and 1B
according to some embodiments.
[0012] FIG. 7 illustrates a graphical user interface of a remote
device associated with the power tool of FIGS. 1A and 1B according
to some embodiments.
[0013] FIG. 8 illustrates a flowchart of a method of operating a
power tool having an electronic clutch according to some
embodiments.
DETAILED DESCRIPTION
[0014] Before any embodiments of the invention are explained in
detail, it is to be understood that the invention is not limited in
its application to the details of construction and the arrangement
of components set forth in the following description or illustrated
in the following drawings. The invention is capable of other
embodiments and of being practiced or of being carried out in
various ways.
[0015] FIGS. 1A-B illustrate a power tool 100 incorporating a
brushless direct current (DC) motor. In a brushless motor power
tool, such as power tool 100, switching elements are selectively
enabled and disabled by control signals from a controller to
selectively apply power from a power source (e.g., battery pack) to
drive a brushless motor. The power tool 100 is a brushless hammer
drill having a housing 102 with a handle portion 104 and motor
housing portion 106. The power tool 100 further includes an output
unit 107, a clutch selector ring (or clutch collar) 108, a mode
selector ring 109, forward/reverse selector 110, speed select
switch 111, trigger 112, a mode selector pushbutton 113, a battery
interface 114, and light 116. The mode selector ring 109 allows a
user to select between a drilling mode, a driving mode, a hammering
mode, and an adaptive mode. When in the adaptive mode, the mode
selector pushbutton 113 may be activated (e.g., pushed) to cycle
through adaptive modes defined by control profiles of the tool 100.
The clutch collar 108 allows a user to select between various
clutch settings, such as settings 1-13 or the even values between
2-26 (i.e., settings 2, 4, 6, 8, . . . 24, 26). Other embodiments
include a clutch collar 108 having fewer or more setting options.
The speed select switch 111 is a two-position switch that slides
between a high speed and a low speed. In some embodiments, the
speed select switch 111 includes additional speed settings (e.g.,
high, medium, and low).
[0016] FIG. 2 illustrates a simplified block diagram 120 of the
power tool 100, which includes a power source 122, field effect
transistors (FETs) 124, a motor 126, Hall sensors 128, a motor
control unit 130, user input 132, and other components 133 (battery
pack fuel gauge, work lights (e.g., light emitting diodes (LEDs),
such as the light 116), a current sensor 135, a voltage sensor 136,
and a wireless transceiver 137). The power source 122 provides DC
power to the various components of the power tool 100 and may be a
power tool battery pack that is rechargeable and uses, for
instance, lithium ion cell technology. In some instances, the power
source 122 may receive alternating current (AC) power (e.g.,
120V/60 Hz) from a tool plug that is coupled to a standard wall
outlet, and then filter, condition, and rectify the received power
to output DC power.
[0017] Each of the Hall sensors 128 outputs motor feedback
information, such as an indication (e.g., a pulse) when a magnet of
the motor's rotor rotates across the face of that Hall sensor.
Based on the motor feedback information from the Hall sensors 128,
the motor control unit 130 can determine the position, velocity,
and acceleration of the rotor. The motor control unit 130 also
receives user controls from user input 132, such as by depressing
the trigger 112 or shifting the forward/reverse selector 110. In
response to the motor feedback information and user controls, the
motor control unit 130 transmits control signals to control the
FETs 124 to drive the motor 126. By selectively enabling and
disabling the FETs 124, power from the power source 122 is
selectively applied to stator coils of the motor 126 to cause
rotation of a rotor. Although not shown, the motor control unit 130
and other components of the power tool 100 are electrically coupled
to the power source 122 such that the power source 122 provides
power thereto.
[0018] The current sensor 135 detects current to the motor, for
example, by detecting current flowing between the power source 122
and the FETS 124 or between the FETS 124 and the motor 126, and
provides an indication of the current sensed to the motor control
unit 130. The voltage sensor 136 detects voltages of the power tool
100, such as a voltage level of the power source 122 and a voltage
across the motor 126. The wireless transceiver 137 provides a
wireless connection between the motor control unit 130 and an
external device to enable wireless communication with the external
device, such as a remote device 140.
[0019] In some embodiments, the motor control unit 130 includes a
memory and an electronic processor configured to execute
instructions stored on the memory to effect the functionality of
the motor control unit 130 described herein.
[0020] The tool 100 includes an electronic clutch, also referred to
as an e-clutch. More particularly, the tool 100 includes an
e-clutch control module 134. The e-clutch control module 134 may be
implemented in hardware, software, or a combination thereof. In the
illustrated embodiment, the e-clutch control module 134 includes
instructions stored on and executed by the motor control unit 130
to implement the e-clutch functionality described herein. The
e-clutch control module 134 takes input from a user from the clutch
collar 108. As will be discussed in more detail below, the clutch
collar 108 provides the user a rotatable selector that provides an
electrical signal indicative of the user selection to the e-clutch
control module 134. The position of the speed select switch 111,
which a user can toggle between two settings (for example, a high
speed setting ("1") and a low speed setting ("2")), is monitored by
the e-clutch control module 134 as well.
[0021] The user selection on the clutch collar 108 is translated
into a desired/target torque output level for the tool 100. Then,
when the tool 100 is in operation, the e-clutch control module 134
calculates an output torque of the power tool by taking into
account one or more of a gear ratio, battery current, effect of
speed control or pulse-width-modulation (PWM) on root mean squared
(RMS) current, and changes in motor velocity and acceleration. For
example, the e-clutch control module 134 calculates the output
torque based on a current flowing to the motor 126 as sensed by the
current sensor 135. When the target torque is reached, the motor
control unit 130 generates an indication of reaching the target
torque by one or more of stopping the tool 100 from further
driving, shaking (i.e., ratcheting) the motor 126 to indicate that
the target torque has been reached, and flashing the light 116 to
indicate that the target torque has been reached.
[0022] The clutch collar 108 allows the user to select the desired
torque level at which the tool 100 clutches. The clutch collar 108
is able to rotate continuously and is not limited, for example, to
a single revolution or 360 degrees of rotation. In other words, the
clutch collar 108 is able to be rotated multiple revolutions (i.e.,
more than 360 degrees of rotation). The continuous rotation feature
allows the clutch collar 108 to go from a maximum torque setting
(e.g., at a 0 degree rotational position) to the minimum torque
setting (e.g., at a 359 degree rotational position), which are
adjacent, more quickly than if the clutch collar 108 had to rotate
back through the various intervening settings between the maximum
and minimum setting.
[0023] In other embodiments, the clutch collar 108 is limited in
rotation, for example, by a rotational stop physically blocking
rotation beyond a certain point (e.g., 180 degrees, 270 degrees,
300 degrees, 360 degrees, 540 degrees, 720 degrees, an amount
between 300 and 360 degrees, or another degree amount). As an
example, the clutch collar 108 may include a projection that
rotates with the collar and the motor housing 106 may have a fixed
tab (i.e., a rotational stop). The clutch collar 108 is free to
rotate until the projection abuts the fixed tab. The projection and
tab may be internal (i.e., inside the clutch collar 108 and motor
housing 106, respectively) or external (i.e., on an outside surface
of the clutch collar 108 and the motor housing 106,
respectively).
[0024] The clutch collar 108 includes a wiper (not shown) that
contacts one of several resistive elements, each associated with a
particular clutch setting. The particular resistive element
contacted by the wiper depends on the rotational position of the
clutch collar 108.
[0025] For instance, FIGS. 3A-B illustrate a front side and a back
side, respectively, of a printed circuit board assembly (PCBA) 200
associated with the clutch collar 108, and FIG. 4 illustrates a
circuit diagram 201 of the PCBA 200 coupled to the motor control
unit 130. The PCBA 200 includes a mode pin 202, an e-clutch (EC)
pin 204, a power pin (Vcc) 206, and a ground pin (GND) 208. As
shown in FIG. 5, the mode pin 202 and the e-clutch pin 204 are
coupled to input pins of the motor control unit 130. The PCBA 200
also includes thirteen surface mount resistors, R1-R13, each having
a different resistance value and conductively coupled to a
different one of thirteen wiper connection points (S1-S13) and
being associated with a different one of the thirteen clutch
settings (1-13). When a user rotates the clutch collar 108 and
stops at a particular clutch setting (e.g., 2), the wiper contacts
a conductive PCBA track (e.g., wiper connection point S2) of the
associated resistor (e.g., R2) to complete a circuit including the
e-clutch pin 204. The conductive tracks for the thirteen resistors
are viewable on the front side of the PCBA 200 in FIG. 3A. The
motor control unit 130 and, particularly, the e-clutch control
module 134, receives an electronic signal indicating that the wiper
has contacted the particular resistor (e.g., R2). The e-clutch
control module 134 interprets the signal and determines that the
user has selected a particular setting (e.g., 2). From the user
perspective, the clutch collar has an interface similar to a
mechanical clutch, ensuring that the user will understand how to
use the clutch.
[0026] In some embodiments, the ability to continuously rotate the
clutch collar 108 (e.g., multiple revolutions in the clockwise
direction, and the counter-clockwise direction), allows the clutch
collar 108 to specify more settings than wiper-resistor positions
on the PCBA 200. For instance, when rotating the clutch collar 108
so that the wiper moves clockwise on the PCBA 200 shown in FIG. 3A
(going from S1 to S2 through S13), if the user continues to rotate
the clutch collar 108 past position S13, eventually the wiper will
again contact position S1. The e-clutch control module 134
determines, based on outputs from the e-clutch pin 204, that the
clutch collar 108 went from position S13 to S1 without going
through positions S12-S2. Thus, this position S1 can be treated as
a fourteenth position (S14). If the clutch collar 108 continues to
rotate in the clockwise direction, each subsequent position is
likewise treated as a new position. For example, S2 would be a
fifteenth position (S15), S3 would be a sixteenth position (S16),
and so on. A similar expansion of positions is provided through
rotating the clutch collar 108 counter clockwise to go directly
from position S1 to S13, without going through intervening
positions S2-S12.
[0027] Accordingly, the continuously rotating clutch collar 108
essentially allows an infinite number of settings to be indicated,
as a user can continuously rotate in a first direction to
continuously increment the torque setting, and continuously rotate
in the opposition direction to decrement the torque setting. In
turn, the e-clutch control module 134 can provide a maximum and
minimum torque setting (e.g., in software) where, for instance,
further increments from the clutch collar 108 are ignored because
the maximum setting has been reached. Additionally, the increased
number of setting positions allows tuning of a torque setting with
finer granularity. For instance, rather than dividing up the
potential torque settings among thirteen positions, the e-clutch
control module 134 can divide the same range of potential torque
settings among 26, 39, 50, 100, or another number of positions.
[0028] The PCBA 200 is further associated with the mode selector
ring 109 to allow a user to select between the drilling mode,
driving mode, hammering mode, and adaptive mode. The PCBA 200
includes further surface mount resistors R31, R32, R33, and R34 on
the bottom portion of the PCBA 200, each resistor being
conductively coupled to a wiper connection point (M1-M4) and being
associated with one of the four modes for selection. Similar to the
clutch collar 108, the mode selector ring 109 includes a wiper that
contacts a resistive element (R31-R34) to complete a circuit and
indicate the mode selection to the motor control unit 130, albeit
the signal is output via the mode pin 202, rather than the e-clutch
pin 204.
[0029] The position of the speed select switch 111, which a user
can toggle between two settings (e.g., a "1" and "2"), is monitored
by the e-clutch control module 134 as well. A similar resistor,
wiper, and PCBA track setup as described with respect to FIGS. 3A,
3B, and 4 is used to track the position of the speed select switch
111 and, therefore, the user's selection of the speed setting (gear
ratio) of the tool 100. In some embodiments, the e-clutch control
module 134 receives the speed setting and accounts for the gear
ratio of the speed setting such that a consistent output torque for
a given clutch setting is obtained regardless of the of speed
setting selected. In other embodiments, the e-clutch control module
134 applies a different target torque dependent on the speed
setting such that a different output torque is obtained for a given
clutch setting at different speed settings.
[0030] In other embodiments, rather than a wiper-resistor ring
technique, different clutch collar selection and mode selection
user interface technology is used, such as inputs using mutual
inductive sensing and capacitive sensing.
[0031] The e-clutch control module 134 estimates the output torque
of the tool 100 (torque at the shaft) using a measurement of
battery current. The current sensor 135, or another sensor used to
infer battery current, provides a measurement to the e-clutch
control module 134. For instance, to determine battery current, the
current sensor 135 may be positioned to measure the current along
the connection between the power source 122 and the FETs 124
labeled "power" in FIG. 2.
[0032] The current-torque relationship is fairly linear, and the
relationship depends on a motor constant (e.g., torque per unit
current (k_t)), gear ratio, gear friction, motor speed and other
factors. Determining the output torque of the tool 100 based on
current may be improved by subtracting current that is due to motor
inertia from the measured battery current. The inertia is specific
to the motor used and takes into account the effects of velocity
and acceleration. Taking motor inertia into consideration when
estimating torque assists in preventing inadvertent shutdowns on
startup or due to changes in the trigger position, where the
current-torque relationship can sometimes be non-linear,
unreliable, or both. The current-to-torque calculation may also be
improved by calculating an RMS current based on the measured
battery current, a PWM duty ratio, and motor design
characteristics. This calculation helps maintain a similar torque
output across different PWM duty ratios. The output torque
calculation may also account for the gear ratio of the power tool
100, which is selected by the user via the speed select switch 111.
For example, the output torque calculation includes one or more of
different offsets and constants, which may be empirically
determined, to compensate for the different speed settings (i.e.,
gear ratios) selectable by the speed select switch 111.
[0033] The calculated output torque is compared against the
threshold torque level set by the user (e.g., via the clutch collar
108) and the tool 100 provides feedback when the threshold torque
level is met or exceeded. In some embodiments, because the output
torque calculation takes into consideration and accounts for the
gear ratio indicated by the speed select switch 111, regardless of
the particular speed setting selected, the tool 100 achieves
approximately the same torque output for a particular torque
setting (e.g., "2") selected by the user via the clutch collar 108.
A torque level (or, torque value) that is considered approximately
the same as another torque level may vary by embodiment and may be,
for example, within 2% of the other torque level, within 5% of the
other torque level, or within 10% of the other torque level.
[0034] The tool 100 indicates to the user that the desired torque
has been reached by ratcheting the motor and flashing the light
116. By ratcheting the motor 126, the e-clutch control module 134
simulates to the user the ratcheting feel and sound of a mechanical
clutch. This technique makes the experience for the user similar to
a mechanical clutch and it is also cost effective because no
additional hardware is needed. The e-clutch control module 134 will
also control the light 116 to blink when the tool 100 has reached
the selected target torque.
[0035] The feedback (e.g., ratcheting) intensity is scaled up and
down with the desired output torque to prevent the ratcheting from
being stronger than the target torque, while maximizing or ensuring
the effectiveness of the feedback to the user. The ratcheting of
the motor 126 is implemented by controlling a pulse-width modulated
(PWM) signal generated by the motor control unit 130 to drive the
motor 126 (via the FETS 124) to be output in short bursts. For
instance, the PWM signal generated by the motor control unit 130
cycles between an active state with a non-zero percent duty cycle
for a first time period, and an inactive (off) state with a zero or
near zero percent duty cycle for a second time period. In some
instances, the frequency and duty cycles for the active and
inactive periods of the PWM signal may vary during the course of
ratcheting. The amount of motor ratcheting generated is based on
the target torque selected by the user. More particularly, the
higher the target torque selected (e.g., as indicted by the clutch
collar 108 and determined by the motor control unit 130), the more
motor ratcheting generated by the tool 100 to indicate when the
target torque is reached. Similarly, the lower the target torque
selected, the less motor ratcheting generated by the tool 100 to
indicate when the target torque is reached. Scaling the motor
ratcheting in accordance with the selected target torque level 1)
prevents over-torqueing a fastener from the ratcheting motion
itself, which could occur if the amount of motor ratcheting is too
high; and 2) allows a level of motor ratcheting commensurate with
the driving action so as to be low enough at low torques to not
startle the user and high enough at high torques to be felt and
recognized by the user.
[0036] To scale the intensity of the motor ratcheting, the length
of time that the PWM signal is active and not active can be
adjusted. Generally, the longer the active time period, the more
intense the ratcheting effect. Similarly, the duration of the
inactive time period of the PWM signal can be adjusted to increase
and decrease the intensity of the ratcheting feedback. Generally,
the longer the PWM signal is inactive, the less intense the
ratcheting feedback. For instance, to increase the intensity of the
ratcheting, the time period that the PWM signal is active is
increased, the time period that the PWM signal is inactive is
decreased, or both.
[0037] The particular threshold torque level used by the tool 100
varies depending on the selected mode of the tool 100. When in the
drilling mode and the hammering mode, as selected via the mode
selector ring 109, the tool 100 generally does not implement
threshold torque levels as described above. When in the driving
mode, the e-clutch control module 134 uses the default threshold
torque level setting assigned to the currently selected torque
setting indicated by the rotational position of the clutch collar
108. The e-clutch control module 134 may include a mapping of
default threshold torque levels corresponding to the settings of
the clutch collar 108. When in the adaptive mode, as indicated by
the mode selector ring 109 based on a user selection, the tool 100
may operate implement threshold torque levels as described above.
The threshold torque levels may be set through wireless
communications between the power tool 100 and the remote device
140, as described in further detail below.
[0038] FIG. 5 illustrates a block diagram of the remote device 140.
The remote device 140 may be, for example, a smart phone, laptop,
tablet, desktop, or other computing device. The remote device 140
includes a memory 145, an electronic processor 150, a touchscreen
display 155, and a wireless transceiver 160 coupled by a bus 165.
The memory 145 stores instructions, including those for a graphical
user interface, that are executed by the electronic processor 150
to perform the processing functions of the remote device 140
described herein. The touchscreen display 155 displays information
for a user and receives input from a user. The touchscreen display
155 is one example of a user interface and, in some embodiments
further or alternative user interface elements are included in the
remote device 140, such as pushbuttons, speakers, keyboards, and
the like. The electronic processor 150 is operable to execute
instructions of the memory 145 to generate a graphical user
interface (GUI) on the touchscreen display 155, such as the GUIs
250 and 300 described in further detail below. The wireless
transceiver 160 is configured to form a wireless communication link
with the wireless transceiver 137 of the power tool 100 (FIG. 2) to
enable the electronic processor 150 to communicate with the motor
control unit 130 (and the e-clutch control module 134 thereof) of
the power tool 100. The wireless transceivers 137, 160 may use the
Bluetooth.RTM. communication protocol, Wi-Fi.RTM. communication
protocol, or another wireless protocol.
[0039] FIGS. 6A and 6B illustrate a GUI 250 generated by the remote
device 140 and configured to receive user input specifying a
control provide (e.g., a custom drive control profile), and to
generate and transmit to the motor control unit 130 the custom
drive control profile to configure operation of the power tool 100.
The power tool 100 and, in particular, the motor control unit 130,
may store multiple control profiles, which may be provided and
updated by the remote device 140. A control profile includes
various tool operating parameters used by the motor control unit
130 to control the power tool 100. When in the adaptive mode, as
indicated by the mode selector ring 109, the motor control unit 130
may cycle through and select the particular control profile to
employ for operation of the power tool 100 in response to
depressions of the mode selector pushbutton 113 by a user. For
example, the power tool 100 may include four control profiles at a
given moment, and each time the mode selector pushbutton 113 is
depressed, the selected control profile used by the motor control
unit 130 to control the power tool changes (e.g., from profile one,
to profile two, to control profile three, to profile four, back to
profile one, and so on). In other embodiments, more or less control
profiles are stored on the power tool 100, or only a single control
profile is stored on the power tool 100.
[0040] The GUI 250 is operable to receive a user selection of the
adjustable mode or the fixed mode via a clutch ring settings
selector 255 (see, e.g., FIGS. 6A and 6B). For the fixed mode, a
set-up screen of which is shown in FIG. 6B, the remote device 140
receives a user selection, via a slider 260 or text box 265, of a
particular fixed torque level (e.g., 75 in-lbs.) or a particular
percentage of available torque (e.g., 75% (of maximum available
torque)). The selected fixed torque level, along with an indication
of the fixed torque mode, is part of a custom drive control profile
that is then wirelessly communicated to the tool 100 and, more
particularly, to the e-clutch control module 134. This selected
torque level is then used by the e-clutch control module 134 as the
torque threshold for the tool 100, regardless of the position of
the clutch collar 108.
[0041] Alternatively, the power tool 100 may receive a custom drive
control profile from the remote device 140 indicating that the tool
100 is to operate in the adjustable mode. In the adjustable mode, a
set-up screen of which is shown in FIG. 6A, the torque threshold
used by the e-clutch control module 134 is the torque level
assigned to the currently selected torque setting indicated by the
rotational position of the clutch collar 108. Initially, the torque
levels assigned to the various torque settings of the clutch collar
108 are the default torque levels that are also used in the driving
mode. However, via the remote device 140, the user can assign new
torque levels to the various settings available to be selected by
the clutch collar 108, over-writing or being used in place of the
default torque levels. The GUI 250 receives the user assignment of
torque levels to settings of the clutch collar 108 (a mapping), and
provides the mapping via the wireless transceiver 160 to the
e-clutch control module 134 as part of a control profile. The
e-clutch control module 134 may store the mapping to a memory of
the motor control unit 130.
[0042] In an example mapping generation by the GUI 250, the user is
able to assign a maximum and minimum torque level (via the slider
260 or text boxes 265) that can be selected via the clutch collar
108, such that the lowest torque setting of the clutch collar 108
is assigned the minimum torque level selected and the highest
torque setting of the clutch collar 108 is assigned the maximum
torque level selected. The remaining intermediate torque settings
are then assigned a proportional torque level between the minimum
and maximum torque levels. For instance, assuming thirteen torque
settings (1-13) on the clutch collar 108 and a user selecting a
minimum torque level of 50 inch-pounds (in.-lbs.) and a maximum
torque level of 110 in.-lbs., the remote device 140 will assign the
following torque levels to the tool 100, in some embodiments:
TABLE-US-00001 TABLE I Torque level Torque Setting Torque level (%
of maximum (Clutch Collar Position) (in-lbs.) torque) 1 50 29% 2 55
32% 3 60 35% 4 65 38% 5 70 41% 6 75 44% 7 80 47% 8 85 50% 9 90 53%
10 95 56% 11 100 59% 12 105 62% 13 110 65%
These assigned values assume a linear scale between minimum and
maximum values. However, in some instances, non-linear scales are
used, such as an exponential scale. In some embodiments, the GUI
250 may receive a selection of the scale to apply via user input.
The maximum and minimum selected torque levels can also be
expressed as a percentage of the maximum torque available. For
instance, the right column of the above table illustrates the
torque levels expressed as a percentage. Furthermore, as noted
above with respect to the continuously rotating feature of the
clutch collar 108, more or fewer than 13 torque setting positions
are assigned a torque level in some embodiments. For instance, each
increment or decrement of the position of the clutch collar 108 can
increment or decrement, respectively, the torque level by 1 in-lb
(or by 1% of maximum torque) until the maximum or minimum torque
levels are reached.
[0043] The GUI 250 further includes a speed setting selector 270 to
select between a high speed mapping and a low speed mapping. In
other words, the GUI 250 is operable to receive torque levels for a
first mapping when the high speed mapping is selected via the speed
setting selector 270, and to receive torque levels for a second
mapping when the low speed mapping is selected via the speed
setting selector 270. The remote device 140 is further operable to
generate and provide to the motor control unit 130 a profile
including the first mapping applicable when the power tool is in
the high speed setting and the second mapping applicable when the
power tool is in the low speed setting (selected via the speed
select switch 111).
[0044] In some embodiments, the profile provided to the power tool
100 based on user input received by the GUI 250 may indicate that,
in one of the speed settings (e.g., the high speed setting), the
power tool 100 is in the adjustable mode and, in the other of the
speed settings (e.g., the low speed setting), the power tool is in
the fixed mode. For example, with the low speed mapping selected on
the GUI 250 via the speed setting selector 270, the GUI 250 may
receive a selection of the adjustable mode via the clutch ring
settings selector 255. Further, with the high speed mapping
selected on the GUI 250 via the speed setting selector 270, the GUI
250 may receive a selection of the fixed mode via the clutch ring
settings selector 255. The remote device 140 then generates a
profile including a first mapping and the adjustable mode for the
low speed setting and a fixed torque level and the fixed mode
indication for the high speed setting. Accordingly, a user is
operable to cycle the power tool 100, by moving the speed select
switch 111, between an adjustable mode whereby the user may specify
a torque level via the clutch collar 108 and a fixed mode whereby
the torque level is fixed (based on input via the GUI 250).
[0045] The profile generated by the remote device 140 and provided
to the power tool 100 based on the GUI 250 may further include a
maximum speed for the motor 126 (one for each of the high and low
speed setting), a trigger ramp up parameter indicating a pace at
which the motor 126 should ramp up to a desired speed, a work light
duration indicating how long to keep the light 116 enabled (e.g.,
after the trigger 112 is pressed or released), and a work light
brightness level.
[0046] Using the e-clutch control module 134, clutch collar 108,
and remote device 140, rather than a traditional mechanical clutch,
allows for more sophisticated mappings of torque control. A
mechanical input (clutch collar 108) provides the user with a
mechanical input mechanism on the tool 100 that is coupled with
programmable electronic control to provide greater tool
customization, intelligence, and usability. The ability to remap
the torque settings selectable by the clutch collar 108 results in
a tool 100 having an extended user interface, where the indications
that are provided by the mechanical input are programmable and are
not fixed. For instance, torque setting "2" is not fixed to
indicate 55 in-lbs. (or another value) of torque. Rather, via the
remote device 140, the meaning of a particular output signal from
the mechanical input can be remapped by the user to indicate
something different to the motor control unit 130 and e-clutch
control module 134. The particular indication from the mechanical
input, specified through the mapping, is then used to control the
motor in a certain predetermined manner. This extended user
interface provided by the remote device 140 provides extended
functionality and customization of the tool 100, which has limited
surface real estate for additional user interface components.
[0047] In some embodiments, the e-clutch control module 134 limits
the maximum allowable torque setting to be that which is allowable
according to applicable laws, rules, or regulations for a driving
tool without a side handle. In some embodiments, the e-clutch
control module 134 receives an input regarding whether a side
handle is present on the tool and limits the maximum allowable
torque setting based on the input. More particularly, when the
e-clutch control module 134 determines that the side handle is not
present, the maximum allowable torque setting is limited to that
which is permitted according to applicable laws, rules, or
regulations. When the e-clutch control module 134 determines that
the side handle is present, the maximum torque setting allowable is
permitted to be higher than when the side handle is not present.
The higher maximum torque setting may again be limited by
applicable laws, rules, or regulations for a driving tool with a
side handle.
[0048] In some embodiments, a switch on the tool 100 allows a user
to indicate to the e-clutch control module 134 whether a side
handle is present. The switch may be similar in function and
structure to the speed select switch 111, may be a push button, or
another electro-mechanical input device that provides an output to
the e-clutch control module 134 indicative of whether a side handle
is present. In another embodiment, attaching the side handle to the
tool itself actuates a switch that provides an indication to the
e-clutch control module 134 of the presence of the side handle, and
removal of the handle provides an indication to the e-clutch
control module 134 that that the side handle has been removed. In
another embodiment, the GUI of the remote device 140 includes an
input (e.g., radio buttons or two-position slider) enabling a user
to select or toggle between a side handle on indication and a side
handle off indication. This selection is then communicated to the
e-clutch control module 134 and used as described above to set the
maximum allowable torque setting.
[0049] As noted above, the tool includes a speed selector switch
111 allowing the user to select between two gear ratios, which
results in a different output speed range. Generally, a high gear
ratio allows for higher maximum speed, but lower maximum torque,
while a low gear ratio allows for a higher maximum torque, but
lower maximum speed. In tools with traditional mechanical clutches,
the maximum torque allowable is typically limited to a maximum
torque to be provided in the high gear ratio (high speed) mode. As
a result, while the low gear ratio mode would allow for a higher
maximum torque absent the mechanical clutch, the mechanical clutch
limits the maximum torque allowable in the low gear ratio (low
speed) mode to the maximum torque to be provided in the high gear
ratio mode. As such, the higher torques of the low gear ratio mode
remain unavailable in a clutching mode. In contrast, the tool 100
includes an e-clutch rather than a mechanical clutch. The
configurability of the e-clutch control module 134 removes the
torque limit imposed by the higher gear ratio to be able to take
advantage of the extra torque levels available by the low gear
ratio.
[0050] Accordingly, in some embodiments, the e-clutch control
module 134 allows a user to specify a higher torque level for the
low speed mode than is selectable for the high speed mode. For
instance, in FIGS. 6A-B, the low speed mode is selected and the
maximum torque allowed is approximately 175 in-lbs., which is the
same maximum torque allowed in the high speed mode. However, in
some embodiments, the tool 100 can achieve a higher torque output
while in the low speed mode. Accordingly, in some embodiments, the
maximum selectable torque level is a first value (e.g., 175
in-lbs.) when in the high speed mode; but, in the low speed mode,
the maximum selectable torque level is a greater value (e.g., 300
in-lbs. or 1000 in-lbs.).
[0051] In some embodiments, the e-clutch control module 134 allows
a user to individually provide a torque level for each setting of
the clutch collar 108. A GUI of the remote device 140 may include a
text box, slider, or other input mechanism, for each setting of the
clutch collar 108 to enable a user to enter a custom torque level
for each clutch collar setting. For example, the user may enter 200
in-lbs for setting 1, 150 in-lbs for setting 2, and 700 in-lbs for
setting 3. In other embodiments, the GUI of the remote device 140
may receive, from a user, custom values for a subset of the
settings, and a range for the other settings. For instance, for a
clutch collar 108 having thirteen settings (e.g. 1-13), the GUI may
receive custom torque levels for settings the three settings (e.g.,
1-3), and a range for the remaining settings (e.g., 4-13) defined
by a maximum value and a minimum value. The remote device 140 may,
in turn, divide the range among the remaining settings (e.g.,
4-13), similar to as described above with respect to Table I.
[0052] In some embodiments, the e-clutch control module 134
receives via a GUI of the remote device 140 different ranges for
different subsets of the settings of the clutch collar 108. For
example, the GUI may provide a mapping of torque levels to the
e-clutch control module 134, based on received user input,
specifying a first range of torques for a first group of settings
(e.g., 1-5) of the clutch collar and a second range of torques for
a second group of settings (e.g., 6-13) of the clutch collar, the
ranges each defined by maximum and minimum torque levels similar to
as described above.
[0053] FIG. 7 illustrates another graphical user interface, GIU
300, generated by the remote device 140 and used to configure the
tool 100. The GUI 300 is configured to receive user input
specifying a custom drill control profile, which is then
transmitted by the remote device 140 to the power tool 100 to
configure operation of the power tool 100. The GUI 300 is similar
to the GUI 250 of FIGS. 6A-B, but includes different features,
including an anti-kickback feature block 301. More particularly,
the GUI 300 includes an anti-kickback toggle 302 that has an enable
and a disable position, selectable by the user. For instance, as
illustrated in FIG. 7, the anti-kickback toggle 302 is in the
enabled position, but is switched to the disabled position by
swiping to the left on the GUI 300 (e.g., on a touch screen of the
remote device 140). When enabled, the user is operable to set the
sensitivity of the anti-kickback feature by setting a torque
shutoff level (i.e., an anti-kickback torque level). In the
illustrated example, the user may adjust the torque shutoff level
between level 1 and level 10 by sliding the slider 304. The GUI 300
also includes a torque shutoff level indicator 306 indicating the
currently selected torque shutoff setting, which is set to level 3
in FIG. 7. After the remote device 140 receives the user settings
of the custom drill profile via GUI 300, the remote device 140
transmits the profile (configuration data) to the power tool 100
wirelessly or via a wired connection, which is received by the
motor control unit 130. As previously described, the mode selector
pushbutton 113 may be pressed to cycle through profiles of the tool
100 and to select the custom drill control profile having the
anti-kickback feature enabled.
[0054] In operation, while the power tool 100 is performing a
drilling operation with the anti-kickback feature is enabled, the
e-clutch control module 134 monitors the battery current to the
motor 126 using the current sensor 135, as described above. The
e-clutch control module 134 also determines a current threshold
based on the selected torque shutoff setting (e.g., using a look up
table mapping each torque shutoff setting to a current value). When
the e-clutch control module 134 determines that the battery current
level reaches the current threshold, the motor control unit 130
ceases driving the motor 126 to bring the motor 126 to a quick
stop. Thus, the motor control unit 130 infers that a kickback
situation is occurring based on an increase in motor torque, which
is inferred via battery current, and shuts down the motor 126.
[0055] When the anti-kickback toggle 302 is disabled, and the
remote device 140 communicates the custom drill profile
configuration data to the power tool with the disabled feature
status, the power tool 100 proceeds without a torque shutoff as
described.
[0056] As illustrated in FIG. 7, other tool operation parameters
may be specified via the GUI 300. For example, the GUI 300 is
operable to receive a maximum speed for the motor 126 (for both the
high and low speed setting), a trigger ramp up parameter indicating
a pace at which the motor 126 should ramp up to a desired speed, a
work light duration indicating how long to keep the light 116
enabled (e.g., after the trigger 112 is pressed or released), and a
work light brightness level. The GUI 300, in turn, generates a
custom drill control profile including the specified parameters,
which is transmitted to the motor control unit 130. The profile may
be stored in a memory of the motor control unit 130. The motor
control unit 130, in turn, controls the power tool 100 in
accordance with the parameters specified by the custom drill
control profile.
[0057] FIG. 8 illustrates a flowchart of a method 700 of operating
a power tool 100 having an electronic clutch. The method 700
includes receiving a mapping for the clutch collar 108 (at step
710). For example, the mapping may be part of a profile generated
by the remote device 140 in response to user inputs received by the
GUI 250 (FIGS. 6A and 6B). The profile may also include an
indication of a mode specified via the GUI 250, such as an
adjustable mode or a fixed mode. The mapping indicates or assigns a
torque level for each of the plurality of positions (that is,
plurality of settings) of the clutch collar 108. The motor control
unit 130 receives and stores the mapping from the remote device 140
via the wireless transceiver 137. A processor of the motor control
unit 130 may store the mapping in a memory of the motor control
unit 130.
[0058] In some embodiments, as described above, the mapping
includes torque levels for two or more revolutions of the clutch
collar 108. For example, the mapping may include torque levels
corresponding to a plurality of settings for a first revolution of
the clutch collar and a second plurality of torque levels
corresponding to the plurality of settings for a second revolution
of the clutch collar. Assuming that the clutch collar 108 includes
thirteen settings for one revolution of the clutch collar 108, this
mapping may include twenty-six torque levels, one for each setting
(or, position) of the clutch collar 108 over two revolutions. In
some embodiments, torque levels for more than two revolutions of
settings of the clutch collar are provided. In some embodiments,
the mapping specifies a maximum torque level, and minimum torque
level, and an increment/decrement level indicating the change in
target torque levels between settings of the clutch collar 108.
[0059] At step 720, the motor control unit 130 detects the clutch
collar 108 position selected by the user of the power tool 100. As
described above with respect to FIGS. 3A, 3B, and 4, the user may
rotate the clutch collar 108 to select a particular torque level.
At step 730, the motor control unit 130 determines the torque level
for the position of clutch collar 108 selected by the user. The
motor control unit 130 determines this torque level based on the
mapping received at step 710. As described above, in some
embodiments, the remote device 140 may transmit a profile to the
power tool 100 including a user-specified fixed torque level. In
these embodiments, the motor control unit determines the torque
level to be the fixed torque level received from the remote device
140, which may occur by the motor control unit 130 ignoring the
position of the clutch collar 108, ignoring the speed setting, or
assigning the fixed torque level to each of the positions of the
clutch collar 108 such that the fixed torque level is selected
regardless of the position of the clutch collar 108.
[0060] At step 740, the motor control unit 130 detects a torque of
the power tool 100. The motor control unit 130 detects the torque,
for example, based on motor current. For example, the current
sensor 135 senses the current flowing to the motor 126 and provides
a signal indicative of the current to the motor control unit 130.
The motor control unit 130 may use techniques described above to
determine the torque based on the signal received from the current
sensor 135.
[0061] At step 750, the motor control unit 130 determines whether
the toque of the power tool 100 exceeds the torque level determined
at step 730. In some embodiments, this determination may involve a
comparison of torque levels (e.g., in inch-pounds or
Newton-meters), and, in other embodiments, the determination may
involve a comparison of current values indicative of a torque
(e.g., in Amperes). When the torque detected in step 740 exceeds
the torque level determined at step 730, the motor control unit 130
generates an indication (at step 760). The indication includes, for
example, flashing the light 116, ratcheting the motor 126, and/or
stopping the motor 126. In other words, in response to determining
that the detected torque of the power tool exceeds the torque
level, the motor control unit 130 may stop the motor 126 to provide
the indication, for instance, by ceasing the sending of driving
signals to the FETs 124 or by controlling the FETs 124 to actively
brake the motor 124. In some embodiments, the motor control unit
130 may ratchet the motor 126 to provide the indication in step
750. In some embodiments, the motor control unit 130 may control
the light 116 to flash to provide the indication. In yet further
embodiments, the motor control unit 130 generates the indication by
using a combination of flashing the light 116, ratcheting the motor
126, and stopping the motor 126. For example, the control unit 130
may flash the light 116 and ratchet the motor 126 for a first
period of time, and then stop the motor 126. The method 700 repeats
steps 740 and 750 until the torque exceeds the torque level
determined in step 730, until a new position of the clutch collar
108 is selected, or until the trigger 112 is released.
[0062] In some embodiments, the mapping received in step 710
includes a first mapping for a high speed setting and a second
mapping for a low speed setting. When the power tool 100 is in the
high speed setting, indicated by the speed select switch 111, the
first mapping is used by the e-clutch control module 134 (e.g., in
step 730 for determining the torque level). However, when the power
tool is in the low speed setting, indicated by the speed select
switch 111, the second mapping is used by the e-clutch control
module 134. Accordingly, the clutch collar 108 may indicate
different desired torque levels at same rotational position
depending on the position for the speed select switch 111. In some
embodiments, the maximum torque level of the first mapping is less
than the maximum torque level of the second mapping.
[0063] In some embodiments, the method includes receiving, from a
speed select switch, a speed setting. The method further includes
compensating for the speed setting in detecting the torque of the
power tool in step 740 or in calculating the torque level in step
730 to provide similar performance regardless of the speed setting.
For example, through the compensation, the torque of the power tool
upon generating the indication in step 750 for a particular setting
of the clutch collar 108 is approximately the same regardless of
the speed setting.
[0064] In some embodiments, the method 700 includes a further step
of receiving, via the wireless transceiver, a request to enter a
fixed torque mode and a fixed torque level. The request and the
fixed torque level may be provided by the remote device 140 as part
of a control profile generated based on user input on the GUI 250.
In a subsequent operation of the power tool, the e-clutch control
module 134 detects, during a subsequent operation of the power
tool, that a subsequent torque of the power tool exceeds the fixed
torque level. The subsequent torque of the power tool is detected
similar to the torque detection of step 740. The motor control unit
130 then generates a second indication that the subsequent torque
exceeds the fixed torque level. The second indication is generated
similar to the indication of step 760, and may include one or more
of stopping the motor 126, ratcheting the motor 126, and flashing
the light 116.
[0065] In some embodiments, the mapping received in step 710
includes a first torque value generated by the remote device 140
based on user input, for example, received via the GUI 250. The
motor control unit 130 uses the first torque value and calculates,
in advance or as needed, torque levels for the plurality of
settings. For example, in step 730, the motor control unit 130
calculates a torque level for the clutch collar setting detected in
step 720 based on the position of the clutch collar setting among
the plurality of settings and the first torque value. The first
torque value may indicate a maximum torque level or a minimum
torque level. Taking, for example, the first torque value as
indicative of a minimum torque level, the motor control unit 130
may calculate the torque level of the setting by assuming a
particular torque increment and incrementing the minimum torque
level by the number of settings that the clutch collar setting is
above the minimum clutch collar setting. Alternatively, the motor
control unit 130 may use a default maximum torque level in
combination with the received minimum torque level and calculate
the torque level for the clutch collar setting to be a value
proportional or corresponding to the position of the clutch setting
among the plurality of settings. For example, a clutch collar
setting of six out of thirteen possible settings would result in a
torque level that is greater than the mid-point between the minimum
and maximum torque levels, assuming a linear scale, and a clutch
collar setting of five out of thirteen settings would result in a
torque level that is below the mid-point. The motor control unit
proceeds to control the motor based on the calculated torque level.
For example, the motor control unit 130 proceeds to execute steps
740, 750, and 760, in some embodiments, and uses the calculated
torque level in the determination of step 750.
[0066] In some embodiments, in step 710, a first torque value and a
second torque value are received, and calculating the torque level
is further based on the second torque value. In some examples, the
first torque value is indicative of a minimum torque level and the
second torque value is indicative of a maximum torque level.
Similar to as described immediately above, the motor control unit
130 uses the first torque value and the second torque value to
calculate, in advance or as needed, torque levels for the plurality
of settings. In some examples, the first torque value is indicative
of a first torque level for a first setting, the second torque
value is indicative of a second torque level for a second setting,
the method further includes associating remaining settings of the
plurality of settings with torque levels between the first torque
level and the second torque level.
[0067] Although the flow chart of FIG. 8 is illustrated and
described as steps performed in a serial manner, one or more blocks
of the method 700 may be executed in parallel or in a different
order than described. Further, the processor of the motor control
unit 130 may execute instructions to implement the steps and
functions of the method 700 attributable to the motor control unit
130.
[0068] Although the tool 100 is described as a hammer drill, in
some embodiments, the tool 100 is a standard, non-hammering
drill/driver, or another drill/driving tool, such as an angle
driver or an impact driver.
[0069] Thus, the invention provides, among other things, a power
tool having a configurable electronic clutch and methods of
configuring an electronic clutch. Various features and advantages
of the invention are set forth in the following claims.
* * * * *