U.S. patent application number 12/815924 was filed with the patent office on 2011-12-15 for agitator with internal twin motor drive system.
Invention is credited to Michael L. Fry, Gerald M. Harrison, Tatsuo Kikkawa, Toru Odachi.
Application Number | 20110303239 12/815924 |
Document ID | / |
Family ID | 44279633 |
Filed Date | 2011-12-15 |
United States Patent
Application |
20110303239 |
Kind Code |
A1 |
Harrison; Gerald M. ; et
al. |
December 15, 2011 |
AGITATOR WITH INTERNAL TWIN MOTOR DRIVE SYSTEM
Abstract
A floor care apparatus includes a housing having a nozzle
assembly and a canister assembly. Both a suction generator and a
dirt collection vessel are carried on the housing. An agitator
cavity is provided on the nozzle assembly. A rotary agitator is
provided in the agitator cavity. The rotary agitator includes an
internal space. An agitator drive system is provided in the
internal space of the rotary agitator. The agitator drive system
includes first and second drive motors that simultaneously drive
the agitator.
Inventors: |
Harrison; Gerald M.;
(Lancaster, KY) ; Fry; Michael L.; (Danville,
KY) ; Odachi; Toru; (Gamou-Gun, JP) ; Kikkawa;
Tatsuo; (OumiHachiman-City, JP) |
Family ID: |
44279633 |
Appl. No.: |
12/815924 |
Filed: |
June 15, 2010 |
Current U.S.
Class: |
134/6 ;
15/389 |
Current CPC
Class: |
A47L 5/30 20130101; A47L
9/0411 20130101; A47L 9/0438 20130101 |
Class at
Publication: |
134/6 ;
15/389 |
International
Class: |
A47L 5/26 20060101
A47L005/26 |
Claims
1. A floor care apparatus, comprising: a housing including a nozzle
assembly and a canister assembly; a suction generator carried on
said housing; a dirt collection vessel carried on said housing; an
agitator cavity provided on said nozzle assembly; a rotary agitator
provided in said agitator cavity, said rotary agitator including an
internal space; and an agitator drive system provided in said
internal space of said rotary agitator, said agitator drive system
including a first drive motor and a second drive motor.
2. The apparatus of claim 1, wherein said first and second drive
motors are aligned within said internal space.
3. The apparatus of claim 2, wherein said first drive motor is
provided adjacent a first end of said rotary agitator and said
second drive motor is provided adjacent a second end of said rotary
agitator so as to provide weight balance.
4. The apparatus of claim 3, further including a first intake
opening at a first end of said agitator, a second intake opening at
a second end of said agitator and an exhaust outlet in a wall of
said rotary agitator between said first drive motor and said second
drive motor.
5. The apparatus of claim 4, further including a first air filter
in said internal space between said first drive motor and said
first intake opening, a second air filter in said internal space
between said second drive motor and said second intake opening and
a third air filter in said internal space between said first and
second drive motors and covering said exhaust outlet; cooling air
being drawn into said filter through said first and second air
intake openings by said first and second drive motors, said cooling
air flowing through said first and second drive motors before being
exhausted from said rotary agitator through said exhaust
outlet.
6. The apparatus of claim 5, further including a first motor
support engaging said first motor and mounting said first motor to
said nozzle assembly and a second motor support engaging said
second motor and mounting said second motor to said nozzle
assembly.
7. The apparatus of claim 6, further including a first bearing
assembly provided between said first motor support and said first
end of said rotary agitator and a second bearing assembly provided
between said second motor support and said second end of said
rotary agitator.
8. The apparatus of claim 7, further including a first power
transmission assembly received in said internal space and
transmitting power from said first drive motor to said rotary
agitator and a second power transmission assembly received in said
internal space and transmitting power from said second drive motor
to said rotary agitator.
9. The apparatus of claim 8, wherein said first drive motor
includes a first drive shaft and said second drive motor includes a
second drive shaft.
10. The apparatus of claim 9, wherein said first power transmission
assembly includes a first planetary gear set carrier carrying a
first planetary gear set as well as a first drive ring and
associated rubber drive boot.
11. The apparatus of claim 10, wherein said second power
transmission assembly includes a second planetary gear set carrier
carrying a second planetary gear set as well as a second drive ring
and associated rubber drive boot.
12. The apparatus of claim 11, wherein said first planetary gear
set carrier holds a first bearing and said first drive shaft
extends through said first bearing while said second planetary gear
set carrier holds a second bearing and said second drive shaft
extends through said second bearing.
13. The apparatus of claim 12, further including a first annular
gear fixed to a first housing of said first drive motor and a
second annular gear fixed to a second housing of said second drive
motor, said first planetary gear set being driven around said first
annular gear by said first drive motor while said second planetary
gear set is being drive around said second annular gear by said
second drive motor.
14. The apparatus of claim 13, further including a plurality of
axial ribs projecting inwardly into said internal space from said
wall of said rotary agitator.
15. The apparatus of claim 14, wherein said first and second drive
ring and associated rubber drive boot include a plurality of spaced
channels that receive and engage said plurality of axial ribs on
said wall of said rotary agitator so that said rotary agitator is
rotated with said first and second planetary gear set carriers.
16. A method of driving a rotary agitator in a vacuum cleaner
comprising: providing a first agitator drive motor; providing a
second agitator drive motor; and simultaneously driving said rotary
agitator with said first agitator drive motor and said second
agitator drive motor.
17. The method of claim 16, including mounting both of said first
and second agitator drive motors in an internal space within said
rotary agitator.
18. The method of claim 17, including aligning said first and
second agitator drive motors within said internal space in said
rotary agitator while also orienting said first and second agitator
drive motors in opposite directions.
19. The method of claim 18, including driving said first agitator
drive motor in a counter-clockwise direction while simultaneously
driving said second agitator drive motor in a clockwise
direction.
20. The method of claim 19, including reducing the overall diameter
of said rotary agitator by using said first and second agitator
drive motors to drive said rotary agitator instead of a single
drive motor where said single drive motor has a diameter D and a
power output of P while each of said first and second agitator
drive motors has a diameter less than D and a combined power output
of at least P.
Description
TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY OF THE INVENTION
[0001] The present invention relates generally to the floor care
appliance field and, more particularly, to a vacuum cleaner
incorporating an agitator with an internal twin motor drive
system.
BACKGROUND OF THE INVENTION
[0002] A vacuum cleaner, equipped with a rotary agitator having a
single internal drive motor, is disclosed in U.S. Pat. No.
7,070,636. This patent is owned by the assignee of the present
invention.
[0003] By providing an agitator with an internal drive motor, one
eliminates the need for a drive belt along with the inconvenient
and troublesome maintenance required by such a feature. This
represents a significant benefit. In addition, the overall design
of the drive system is compact. Further, the internal drive system
has proven to be a reliable performer characterized by a long
service life.
[0004] Despite these numerous benefits and advantages, further
improvements are possible. The present invention relates to an
agitator with an internal twin motor drive system. Such an
arrangement provides a number of additional advantages over the
state of the art agitator equipped with a single internal drive
motor.
[0005] Specifically, the internal twin motor drive system allows
one to provide an agitator of reduced diameter with the same level
or even more torque as provided by the state of the art single
internal motor design. Thus, the vacuum cleaner equipped with the
new internal twin motor drive system may be made with a lower
profile. This allows for cleaning under lower bathroom and kitchen
cabinet overhangs and furniture. Further, the twin motors may be
positioned in the agitator to better balance the weight over the
agitator and the overall vacuum cleaner. This functions to increase
the cleaning performance and overall service life of the vacuum
cleaner while providing the vacuum cleaner with neutral handling
characteristics so that it is easier to steer.
SUMMARY OF THE INVENTION
[0006] To achieve the foregoing and other objects, and in
accordance with the purposes of the present invention as described
herein, an improved floor care apparatus is provided. That floor
care apparatus comprises a housing including a nozzle assembly and
a canister assembly, a suction generator carried on the housing,
and a dirt collection vessel carried on the housing. An agitator
cavity is provided on the nozzle assembly. A rotary agitator is
provided in the agitator cavity. The rotary agitator includes an
internal space. An agitator drive system is provided in the
internal space of the rotary agitator. That agitator drive system
includes a first drive motor and a second drive motor.
[0007] More specifically, the first and second drive motors are
aligned within the internal space. The first drive motor is
provided adjacent the first end of the rotary agitator while the
second drive motor is provided adjacent a second end of the rotary
agitator in order to provide weight balance. An air intake opening
is provided at each end of the rotary agitator. An air exhaust
outlet is provided between the first and second drive motors. Air
filters are provided in the internal space between the intake
openings and the drive motors and cooling air is drawn into these
filters through the intake opening by the first and second drive
motors. The cooling air flows through the first and second drive
motors before being exhausted from the rotary agitator through the
exhaust outlet.
[0008] In accordance with an additional aspect of the present
invention, a method is provided for driving a rotary agitator in a
vacuum cleaner. The method comprises providing a first agitator
drive motor, providing a second agitator drive motor and
simultaneously driving the rotary agitator with the first and
second agitator drive motors.
[0009] More specifically, the method includes mounting both the
first and second agitator drive motors in an internal space within
the rotary agitator. Further, the method includes aligning the
first and second agitator drive motors within the internal space
while also orienting the first and second agitator drive motors in
opposite directions. Thus, the method includes driving the first
agitator drive motor in a clockwise direction while simultaneously
driving the second agitator drive motor in a counter-clockwise
direction.
[0010] Still further, the method includes the step of reducing the
overall diameter of the rotary agitator. This is done by using
first and second agitator drive motors to drive the rotary agitator
instead of a single drive motor where the single drive motor has a
diameter D and power output P while each of the first and second
agitator drive motors has a diameter less than D and a combined
power output of at least P. Thus, the resulting agitator has a
reduced diameter allowing the vacuum cleaner or floor care
appliance to have a lower overall profile so as to better reach
under cabinet overhangs, furniture and the like. At the same time,
vacuum cleaner or floor care appliance performance is in no way
compromised.
[0011] In the following description there is shown and described
several different embodiments of the invention, simply by way of
illustration of some of the modes best suited to carry out the
invention. As it will be realized, the invention is capable of
other different embodiments and its several details are capable of
modification in various, obvious aspects all without departing from
the invention. Accordingly, the drawings and descriptions will be
regarded as illustrative in nature and not as restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings incorporated herein and forming a
part of the specification, illustrate several aspects of the
present invention and together with the description serve to
explain certain principles of the invention. In the drawings:
[0013] FIG. 1 is a perspective view of a vacuum cleaner constructed
in accordance with the teachings of the present invention;
[0014] FIG. 1a is a schematical diagram of the vacuum cleaner
illustrated in FIG. 1;
[0015] FIG. 2 is a cross-sectional view through the nozzle assembly
of the vacuum cleaner showing the agitator and the agitator drive
system;
[0016] FIG. 2a is a detailed transverse cross-sectional view
through the agitator illustrating the first power transmission
assembly received in the internal space of the agitator;
[0017] FIG. 2b is a detailed cross sectional view of the first end
of the agitator including the first drive motor and first
transmission assembly; and
[0018] FIG. 3 is an exploded perspective view of the agitator and
the agitator drive system.
[0019] Reference will now be made in detail to the present
preferred embodiment of the invention, an example of which is
illustrated in the accompanying drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE
INVENTION
[0020] Reference is now made to FIGS. 1 and 1a showing the floor
care appliance 10 of the present invention. It should be
appreciated that while the floor care appliance 10 is illustrated
as an upright vacuum cleaner, embodiments of the present invention
also include canister vacuum cleaners, extractors and the like
incorporating the rotary agitator and agitator drive system 12 of
the present invention as described in detail below.
[0021] The upright vacuum cleaner 10 illustrated includes a housing
11 having a nozzle assembly 14 and a canister assembly 16. The
canister assembly 16 further includes a control handle 18 and a
hand grip 20. The hand grip 20 carries a control switch 22 for
turning the vacuum cleaner 10 on and off. Of course, electrical
power is supplied to the vacuum cleaner 10 from a standard
electrical wall outlet through a cord (not shown).
[0022] At the lower portion of the canister assembly 16, rear
wheels (not shown) are provided to support the weight of the vacuum
cleaner 10. A second set of wheels on the nozzle assembly 14 (also
not shown) allow the operator to raise and lower the nozzle
assembly through selective manipulation of the height adjustment
switch 24. Such a height adjustment mechanism is well known in the
art. To allow for convenient storage of the vacuum cleaner 10, a
foot latch 26 functions to lock the canister assembly 16 in an
upright position as illustrated in FIG. 1. When the foot latch 26
is released, the canister assembly 16 may be pivoted relative to
the nozzle assembly 14 as the vacuum cleaner 10 is manipulated
to-and-fro to clean the floor.
[0023] The canister assembly 16 includes a cavity 28 adapted to
receive and hold the dirt collection vessel 30. In the illustrated
embodiment, the cavity 28 comprises a filter bag compartment that
is accessed through a removable door 32. A dirt collection vessel
in the form of a replaceable filter bag 30 is received and held in
that cavity. In alternative embodiments of the present invention
the cavity 28 receives a dirt cup. Substantially any design of dirt
cup known in the art may be provided including those designed to
provide cyclonic air flow. As also known in the art, such a dirt
cup may or may not include a main filter assembly.
[0024] In the illustrated embodiment, the housing 11 and, more
particularly, the canister assembly 16 also carries a suction
generator 36. Such a suction generator 36 comprises a suction fan
and cooperating drive motor that function to generate a vacuum air
stream for drawing dirt and debris from the surface to be cleaned.
While the suction generator 36 is illustrated as being carried on
the canister housing 16, it should be appreciated that it could
likewise be carried on the nozzle assembly 14 if desired.
[0025] The nozzle assembly 14 includes an agitator cavity 38 that
houses a rotary agitator 40. As best illustrated in FIG. 2, the
rotary agitator 40 incorporates an outer cylindrical wall 42 that
holds a series of bristle tufts 44 that project outwardly. The
cylindrical wall 42 also defines an internal space 44 that receives
an agitator drive system 46 that will be described in greater
detail below. The wall 42 of the agitator 40 may be made from, for
example, metal, wood, ceramic, plastic and composite materials.
More specifically, such materials include but are not limited to
aluminum, steel, pressed wood and fiberglass reinforced
plastics.
[0026] During operation, the scrubbing action of the bristle tufts
44 on the agitator 40 and the negative air pressure created by the
suction generator 36 cooperate to brush and beat dirt and debris
from the nap of a carpet being cleaned and then draw dirt and
debris laden air from the agitator cavity and suction inlet 38 into
the dirt collection vessel 30. Specifically, the dirt and
dust-laden air passes serially through the suction inlet 38 and
hose and/or integrally molded conduit in the nozzle assembly 14
and/or canister assembly 16 as is known in the art. Next, it is
delivered into the dirt collection vessel/filter bag 30 which
serves to trap the suspended dirt, dust and other particles inside
while allowing the now clean air to pass freely through to the
suction generator 36. A secondary filter (not shown) may be
provided between the dirt collection vessel/filter bag 30 and the
suction generator 36 in order to further insure that no
particulates are ingested by the motor of the suction generator.
After the air stream passes over the motor of the suction generator
36 to provide cooling, it is forced through a final filtration
cartridge 48 before being returned to the environment through an
exhaust port 34.
[0027] As best illustrated in FIG. 2, the agitator drive system
includes a first drive motor 52 and a second drive motor 54. The
two drive motors 52, 54 are aligned along the longitudinal axis A
of the agitator 40 within the internal space 46. The first and
second agitator drive motors 52, 54 are also oriented in opposite
directions. Specifically, the first drive motor 52 is received and
held on a first motor support 56 while the second drive motor 54 is
received and held on a second motor support 58. The first motor
support 56 includes a mounting block 60 keyed into a slot 62 in one
side of the nozzle assembly 14 while the second motor support 58
includes a mounting block 64 that is keyed into a slot 66 at the
opposite side of the nozzle assembly (see also detailed showing in
FIG. 2b). A first bearing assembly 68 is carried on the first motor
support 56 and provided between the first motor support and the
first end of the rotary agitator 40. Similarly, a second bearing
assembly 70 is provided on the second motor support 58 and received
between the second motor support and a second end of the agitator
40. The two bearing assemblies 68, 70 support the agitator 40 in
the agitator cavity 38 of the nozzle assembly 14 while allowing the
agitator to freely rotate relative to the nozzle assembly.
[0028] As further illustrated in FIGS. 2 and 3, the first drive
motor 52 includes a first drive shaft 72 and with first gear teeth
74 while the second drive motor 54 includes a second drive shaft 76
with second gear teeth 78. A first power transmission assembly,
generally designated by reference numeral 80 is received in the
internal space 46 and transmits power from the first drive motor 52
to the rotary agitator 40. Similarly, a second transmission
assembly 82 is received in the internal space 46 and transmits
power from the second drive motor 54 to the rotary agitator 40.
[0029] Reference is now made to FIGS. 2, 2a, 2b and 3 so as to
allow detailed description of the first transmission assembly 80.
As illustrated, the first transmission 80 includes a first
planetary gear set carrier 84 carrying a first planetary gear set
comprising three gears 86, a first drive ring 88 and an associated
rubber drive boot 90. The first drive motor 52 drives the first
drive shaft 72. The drive shaft 72 extends through a bearing 92
held in the hub 94 of the planetary gear set carrier 84. The
planetary gear set carrier 84 includes three stub shafts 96 that
support each of the planetary gears 86. Each of the planetary gears
86 include teeth that mesh with the gear teeth 74 on the drive
shaft 72. Additionally, the planetary gears 86 mesh with the teeth
of an annular gear 98 that is fixed to the housing of the first
drive motor 52 by pin or other means. Thus, it should be
appreciated that as the drive shaft 72 is driven by the first drive
motor 52, the planetary gears 86 are driven around the annular gear
98, thereby causing the planetary gear set carrier 84 to
rotate.
[0030] As noted above, planetary gear set carrier 84 also includes
the drive ring 88 and the associated rubber drive boot 90. The
drive ring 88 and rubber drive boot 90 both include a series of
spaced channels 100 that receive and engage axial ribs 102
projecting inwardly radially from the inner surface of the
cylindrical wall 42 of the rotary agitator 40. Thus, the rotation
of the planetary gear set carrier 84 is transmitted by the drive
ring 88 and associated drive boot 90 directly to and causes like
rotation of the agitator 40. The rubber drive boot 90 provides the
necessary damping to ensure the smooth transmission of power to the
agitator 40.
[0031] The second transmission assembly 82 that transmits power
from the second drive motor 54 to the agitator 40 is substantially
identical to the first transmission assembly 80 and like reference
numbers have been utilized to identify corresponding parts of the
second transmission assembly in the drawing figures. Here it should
be noted that the first drive motor 52 and first transmission
assembly 80 are oriented in a first direction within the internal
space 46 while the second drive motor 54 and second transmission
assembly 82 are oriented in the opposite direction so that the two
appear to be mirror images. Both drive motors 52, 54 simultaneously
drive the rotary agitator 40 through their respective transmission
assemblies 80, 82. To achieve this end the first agitator drive
motor 52 is operated in a counter-clockwise direction while the
second agitator drive motor 54 is operated in a clockwise
direction.
[0032] It is important to provide proper cooling to the first and
second drive motors 52, 54 confined within the internal space 46 in
the rotary agitator 40. Toward this end, a first intake opening 110
is provided at a first end of the agitator 40 and a second intake
opening 112 is provided at a second end of the agitator. A first
air filter 114 is provided in the internal space 46 between the
first intake opening 110 and the first drive motor 52. Similarly, a
second air filter 116 is provided in the internal space 46 between
the second intake opening 112 and the second drive motor 54.
[0033] A third filter 118 is provided in the internal space 46
between the first and second drive motors 52, 54. The third filter
118 covers a series of air exhaust outlets 120 provided in the wall
42 of the agitator 40. Typically the filters 114, 116 and 118 are
made from open cell foam, woven filter media or non-woven filter
media.
[0034] Air is drawn into the air intake openings 110, 112 and then
through the first and second air filters 114, 116 by operation of
the first and second drive motors 52, 54. The air is then forced
past both transmission assemblies 80, 82 and the third filter 118
before being exhausted from the rotary agitator 40 through the
exhaust outlets 120 (note action arrows B in FIGS. 2 and 2b).
[0035] Advantageously, by using an agitator drive system 12
incorporating dual drive motors 52, 54, it is possible to reduce
the overall diameter of the agitator 40 as well as the overall
height of the nozzle assembly 14. The resulting "low profile"
nozzle assembly 14 is capable of more easily fitting under vacuum
cleaning obstacles such as furniture and bathroom and kitchen
cabinets that overhand the floor so as to allow more complete and
convenient cleaning. Further, this is accomplished without any loss
of power P. More specifically, the overall diameter of the rotary
agitator 40 is reduced by using first and second agitator drive
motors 52, 54 to drive the rotary agitator instead of a single
drive motor where the single drive motor has a diameter D and a
power output (torque) P while each of the first and second agitator
drive motors 52, 54 has a diameter less than D and a combined power
output of at least P. For example, a state of the art vacuum
cleaner uses a single internal agitator drive motor to drive the
rotary agitator. That single agitator drive motor has a diameter of
46 mm requiring an agitator with an outer diameter of 56 mm. In
contrast, the rotary agitator 40 of the present invention equipped
with the internal dual motor drive system 12 has an overall
diameter of 46 mm: that is 10 mm less than the old rotary agitator
which is almost an 18% reduction in diameter. This is possible as
the dual drive motors 52, 54 each have an outer diameter of only 39
mm. Specifically, since two drive motors 52, 54 are used instead of
one; the drive motors themselves may be smaller thereby allowing
one to produce a nozzle assembly 14 with a lower overall profile.
Advantageously, this is accomplished without any loss of power.
[0036] The foregoing description of the preferred embodiments of
the present invention have been presented for purposes of
illustration and description. It is not intended to be exhaustive
or to limit the invention to the precise form disclosed. Obvious
modifications or variations are possible in light of the above
teachings. The embodiments were chosen and described to provide the
best illustration of the principles of the invention and its
practical application to thereby enable one of ordinary skill in
the art to utilize the invention in various embodiments and with
various modifications as are suited to the particular use
contemplated. All such modifications and variations are within the
scope of the invention as determined by the appended claims when
interpreted in accordance with the breadth to which they are
fairly, legally and equitably entitled. The drawings and preferred
embodiments do not and are not intended to limit the ordinary
meaning of the claims in their fair and broad interpretation in any
way.
* * * * *