U.S. patent application number 10/128184 was filed with the patent office on 2002-12-19 for walk-behind implement having forward and reverse drives and a method of operation therefor.
Invention is credited to Boyer, Scott G., Cox, C. Paul, Herrick, Todd W., Johnson, Kevin L., Ruebusch, Richard T..
Application Number | 20020189137 10/128184 |
Document ID | / |
Family ID | 23098497 |
Filed Date | 2002-12-19 |
United States Patent
Application |
20020189137 |
Kind Code |
A1 |
Cox, C. Paul ; et
al. |
December 19, 2002 |
Walk-behind implement having forward and reverse drives and a
method of operation therefor
Abstract
A walk-behind self-propelled implement, such as a snow thrower
or lawnmower, for example, is provided. The implement includes
first and second transmission modules associated with a common
single axle to which a pair of drive wheels is attached. The first
and second transmission modules are operable exclusively with
respect to one another to drive the axle and the wheels in a
forward and reverse direction, respectively. A control member
mounted to the handle of the implement includes a forward bail
member pivotable to rotate the control member in a first direction
to urge the wheel to rotate in a forward direction, and a reverse
bail member pivotable to rotate the control member in a second
direction opposite the first direction to urge the wheel to rotate
in a reverse direction.
Inventors: |
Cox, C. Paul; (Sellersburg,
IN) ; Johnson, Kevin L.; (Douglas, GA) ;
Boyer, Scott G.; (Borden, IN) ; Ruebusch, Richard
T.; (New Albany, IN) ; Herrick, Todd W.;
(Tecumseh, MI) |
Correspondence
Address: |
BAKER & DANIELS
111 E. WAYNE STREET
SUITE 800
FORT WAYNE
IN
46802
|
Family ID: |
23098497 |
Appl. No.: |
10/128184 |
Filed: |
April 23, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60286414 |
Apr 25, 2001 |
|
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|
Current U.S.
Class: |
37/242 |
Current CPC
Class: |
A01D 2101/00 20130101;
E01H 5/04 20130101; F16D 23/12 20130101; A01D 34/6812 20130101;
A01D 2034/6843 20130101; A01D 34/69 20130101 |
Class at
Publication: |
37/242 |
International
Class: |
E01H 005/09 |
Claims
What is claimed is:
1. A walk-behind self-propelled implement, comprising: a frame; a
power source mounted to said frame, said power source having a
rotating output shaft; an axle rotatably supported by said frame;
at least one drive wheel attached to said axle; a first
transmission module associated with said axle and operable to
transfer rotation of said output shaft to said axle in a forward
direction; and a second transmission module associated with said
axle and operable to transfer rotation of said output shaft to said
axle in a reverse direction, wherein said first and second
transmission modules are operable exclusively of one another.
2. The implement of claim 1, wherein each of said first and second
transmission modules includes clutch surfaces selectively
engageable with one another to transfer rotation of said output
shaft to said axle.
3. The implement of claim 1, including a control mechanism
connected to said frame, said control mechanism operable to actuate
said clutch surfaces of said first and second transmission modules
exclusively of one another.
4. The implement of claim 1, wherein each of said first and second
transmission modules includes a pair of casings sandwiching said
axle therebetween, respective said casing pairs including bearings
rotatably supporting said axle.
5. The implement of claim 1, wherein each of said first and second
transmission modules includes an input shaft having a worm portion
and a worm gear rotatable with respect to said axle, said worm
portion engaging said worm gear to transfer rotation
therebetween.
6. The implement of claim 5, wherein each of said first and second
transmission modules further includes clutch surfaces selectively
engageable to transfer rotation from said worm gear to said
axle.
7. The implement of claim 5, wherein said first transmission module
includes a right hand worm portion and a right hand worm gear, and
said second transmission module includes a left hand worm portion
and a left hand worm gear.
8. The implement of claim 1, wherein said implement comprises a
snow thrower, said snow thrower including an auger assembly
connected to said frame, said auger assembly including a rotatable
auger driven from said output shaft.
9. The implement of claim 8, wherein said auger is driven from said
output shaft through a belt drive, said belt drive including a
tensioning mechanism operable to engage said belt drive to transfer
rotation of said output shaft to said auger.
10. The implement of claim 1, wherein said implement comprises a
lawnmower, said lawnmower including a blade connected to said
output shaft and rotatable therewith.
11. A walk-behind self-propelled implement, comprising: a frame; a
handle attached to said frame; a power source mounted to said
frame; an axle rotatably supported by said frame, said power source
drivingly coupled to said axle; at least one drive wheel attached
to said axle; and a control member rotatably attached to said
handle, said control member including a forward bail member
pivotable to rotate said control member in a first direction to
urge said wheel to rotate in a forward direction, and a reverse
bail member pivotable to rotate said control member in a second
direction opposite said first direction to urge said wheel to
rotate in a reverse direction.
12. The implement of claim 11, including a first transmission
module associated with said axle and controllable only by said
forward bail member, and a second transmission module associated
with said axle and controllable only by said reverse bail member,
said first and second transmission modules operable exclusively of
one another.
13. The implement of claim 12, wherein each of said first and
second transmission modules include a pair of clutch surfaces
selectively engageable with one another to drivingly couple said
power source to said axle.
14. The implement of claim 12, including a first and second cables
respectively connected between said forward and reverse bail
members and said first and second transmission modules, said first
and second cables translatable by pivoting of said forward and
reverse bail members to actuate said first and second transmission
modules.
15. The implement of claim 12, wherein said implement comprises a
snow thrower, said snow thrower including an auger assembly
connected to said frame, said auger assembly including a rotatable
auger drivingly coupled to said output shaft.
16. The implement of claim 15, wherein said auger is driven from
said power source through a belt drive, said belt drive including a
tensioning mechanism operable to engage said belt drive to transfer
power from said power source to said auger.
17. The implement of claim 12, wherein said implement comprises a
lawnmower, said lawnmower including a blade driven from said power
source.
18. A method of operating a self-propelled walk-behind implement,
comprising the steps of: moving a control member in a first
rotational direction to operably engage only a first transmission
module and effect forward movement of the implement; and reversibly
rotating the control member to operably engage only a second
transmission module and effect reverse movement of the implement.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under Title 35, U.S.C.
.sctn. 119(e) of U.S. Provisional Patent Application Serial No.
60/286,414, entitled WALK-BEHIND IMPLEMENT HAVING FORWARD AND
REVERSE DRIVES AND A METHOD OF OPERATION THEREFOR, filed on Apr.
25, 2001.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to walk-behind self-propelled
implements intended primarily for use as lawnmowers, snow throwers,
cultivators and the like, but may also be applied to larger
implements and vehicles.
[0004] 2. Description of the Related Art
[0005] Lawn and garden implements, for example, mowers, tillers and
snow throwers, often include a transaxle through which power from
an engine is transmitted to ground-engaging wheels attached to
axles extending from the transaxle for propelling the implement.
Typically, the drive source operates at a single, rotary mechanical
speed and propels the implement in a forward direction under manual
control by an operator. Additionally, the drive source is operably
coupled to a working device, such as a blade or auger assembly, for
example, and may be disengaged or placed in a neutral condition by
the operator via a control lever provided on the implement
handle.
[0006] Single stage snow throwers are generally less expensive
relative to their two-stage counterparts. Propulsion of single
stage snow throwers is generally dependant upon substantial
operator intervention to move the implement in a forward or reverse
direction. For example, single stage snow throwers are typically
propelled forward by the auger rather than through mechanical
rotation and propulsion of the wheel(s). Snow thrower speed is
controlled as the operator exerts an upward force on the handle to
increase traction between the auger and the ground to propel the
implement forward. Since the movement of the implement is
substantially dependant on the engagement between the auger and the
ground, it is common for the implement to not track straight.
Furthermore, since the auger is driven in a single direction to
effect a forward motion of the implement, the single stage snow
thrower is not equipped to drive the implement in a reverse
direction, and must be pulled rearward by the operator.
[0007] There is a need for a simple, inexpensive implement such as
a snow thrower, which may be propelled along a substantially
straight direction in both forward and reverse directions, and
which also allows for engagement and disengagement of the working
device. Furthermore, an inexpensive implement is desirable which
includes a single control member to selectively control wheel
direction, and which is not complicated to operate.
SUMMARY OF THE INVENTION
[0008] The present invention overcomes the disadvantages of prior
walk-behind implements by providing a walk-behind implement
including a selectively engageable working device and a pair of
inexpensive transmission modules engageable with a common axle to
allow both forward and reverse movement of the implement through a
control assembly provided on the implement handle.
[0009] In one form thereof, the present invention provides a
walk-behind self-propelled implement, including a frame; a power
source mounted to the frame, the power source having a rotating
output shaft; an axle rotatably supported by the frame; at least
one drive wheel attached to the axle; a first transmission module
associated with the axle and operable to transfer rotation of the
output shaft to the axle in a forward direction; and a second
transmission module associated with the axle and operable to
transfer rotation of the output shaft to the axle in a reverse
direction, wherein the first and second transmission modules are
operable exclusively of one another.
[0010] In another form thereof, the present invention provides a
walk-behind self-propelled implement, including a frame; a handle
attached to the frame; a power source mounted to the frame; an axle
rotatably supported by the frame, the power source drivingly
coupled to the axle; at least one drive wheel attached to the axle;
and a control member rotatably attached to the handle, the control
member including a forward bail member pivotable to rotate the
control member in a first direction to urge the wheel to rotate in
a forward direction, and a reverse bail member pivotable to rotate
the control member in a second direction opposite the first
direction to urge the wheel to rotate in a reverse direction.
[0011] In a further form thereof, the present invention provides a
method of operating a self-propelled walk-behind implement,
including the steps of moving a control member in a first
rotational direction to operably engage only a first transmission
module and effect forward movement of the implement; and reversibly
rotating the control member to operably engage only a second
transmission module and effect reverse movement of the
implement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The above-mentioned and other features and objects of this
invention, and the manner of attaining them, will become more
apparent and the invention itself will be better understood by
reference to the following description of the invention taken in
conjunction with the accompanying drawings, wherein:
[0013] FIG. 1A is a perspective view of a first embodiment of a
walk-behind implement according to the present invention;
[0014] FIG. 1B is a perspective view of a second embodiment of a
walk-behind implement according to the present invention;
[0015] FIG. 2 is a perspective view of a third embodiment of a
walk-behind implement according to the present invention;
[0016] FIG. 3 is a perspective view of the implement of FIG. 1A,
shown with a portion of the housing, the shroud and snow discharge
chute removed;
[0017] FIG. 4 is an enlarged side view of the working device drive
mechanism of the implement of FIG. 3;
[0018] FIG. 5A is a schematic of the implement of FIG. 3, showing
the control assembly connected with corresponding wheel and working
device drive mechanisms;
[0019] FIG. 5B is a schematic of the implement of FIG. 1B, showing
the control assembly connected with corresponding wheel and working
device drive mechanisms;
[0020] FIG. 6A is a bottom view of the implement of FIG. 3;
[0021] FIG. 6B is a bottom view of the implement of FIG. 5B;
[0022] FIG. 7 is a fragmentary top view of the implement of FIG. 3,
showing the pair of transmission modules from just above their
respective sheaves;
[0023] FIG. 8 is a sectional view taken along line 8-8 of FIG. 7,
showing the construction of each transmission module and showing
the arrangement between each intermeshed wheel and axle gear;
[0024] FIG. 9 is an exploded view of one of the transmission
modules of the implement of FIG. 3;
[0025] FIG. 10 is an enlarged view of the encircled area of FIG.
8;
[0026] FIG. 11 is a fragmentary view of the implement of FIG. 1A,
showing the controls;
[0027] FIG. 12 is an enlarged view of the encircled area of FIG.
11;
[0028] FIG. 13 is an enlarged fragmentary view of the handle and
controls of the implement of FIG. 1A, showing the working device
activation control member;
[0029] FIG. 14 is a sectional view of the implement of FIG. 1A,
taken along line 14-14 of FIG. 1A, showing the control assembly in
a disengaged and neutral condition;
[0030] FIG. 15 is the implement of FIG. 14, showing the working
device activation control member in an engaged position and the
drive control member in a disengaged position;
[0031] FIG. 16 is the implement of FIG. 14, showing the working
device activation control member in an engaged position and the
drive control member in an engaged position to propel the implement
forward;
[0032] FIG. 17 is the implement of FIG. 14, showing the working
device activation control member in a disengaged position and the
drive control member in an engaged position to propel the implement
in reverse;
[0033] FIG. 18 is the implement of FIG. 14, showing the working
device activation control member in an engaged position and the
drive control member in a partially engaged position; and
[0034] FIG. 19 is fragmentary perspective of a fourth embodiment of
a walk-behind implement according to the present invention, showing
a modified drive control member and its attachment with the forward
and reverse cable assemblies.
[0035] Corresponding reference characters indicate corresponding
parts throughout the several views. Although the drawings represent
embodiments of the present invention, the drawings are not
necessarily to scale and certain features may be exaggerated in
order to better illustrate and explain the present invention. The
exemplifications set out herein illustrate embodiments of the
invention, and such exemplifications are not to be construed as
being exhaustive or to limit the scope of the invention in any
manner.
DETAILED DESCRIPTION
[0036] Referring to FIG. 1A, a first embodiment of a walk-behind
implement according to the present invention is shown in the form
of a snow thrower. Snow thrower 20a includes frame 22a and a pair
of ground engaging wheels 24a rotatably attached thereto. Frame 22a
includes a substantially horizontal deck 41a (FIG. 3) which
supports engine 26 (FIGS. 1B, 2). The working device or auger
assembly includes auger 28 having a rotating blade. Auger 28 is
rotatably supported by frame 22a and rotates within snow receiving
opening 23 of frame 22a. Engine 26 is operably engaged to ground
engaging wheels 24a to propel implement 20a in either a forward or
reverse direction. Control assembly 32 is provided on handle 30 and
handle 30 includes first end 31 attached to frame 22a and second
end 34 projected outwardly therefrom. Snow received into opening 23
is discharged by auger 28 through discharge nozzle 36 and deflected
by deflection chute 38. Snow thrower 20a includes an engine
enclosing shroud 40.
[0037] Referring to FIG. 1B, a second embodiment of a snow thrower
according to the present invention is shown and differs from snow
thrower 20a in several aspects. Certain elements include reference
numerals having a different letter (e.g., 20a and 20b) appended
thereto which indicates that the corresponding element previously
described in the first embodiment has been modified. As shown, snow
thrower 20b lacks a shroud, and the auger and wheel drive
mechanisms thereof are substantially enclosed underneath deck 41b,
or within frame 22b as described below.
[0038] Referring to FIG. 2, a third embodiment walk-behind
implement according to the present invention is shown in the form
of a lawn mower, including rotating blade 19 mounted on output
shaft 50 of engine 26. Mower 20c includes a pair of driven rear
wheels 24c, and additionally, a pair of non-driven front wheels 42
rotatably attached to frame 22c. Similar to walk-behind implements
20a and 20b, walk-behind implement 20c includes a control assembly
32 to actuate the transfer of power from engine 26 to ground
engaging wheels 24c, resulting in forward or reverse movement of
the implement. Additionally, the control assembly allows an
operator to engage or disengage a rotating blade (not shown)
enclosed underneath deck 41c of frame 22c. Implements 20a, 20b and
20c may include a T-handle 46 connected to start cord 48 for
starting engine 26. Alternatively, or additionally, an electric
starter may be employed.
[0039] Referring to FIG. 5A, engine 26 of implement 20a includes
vertically oriented output shaft 50, and wheel drive pulley 52
keyed to output shaft 50 through known means such as a Woodruff
key, for example. A second pulley or power take off (PTO) pulley 54
is keyed to end 55 of output shaft 50. As best seen in FIG. 6A, PTO
pulley 54 is in driving engagement with pulley 56 of right angle
drive mechanism 58 through belt 62 engaged about the peripheries of
pulleys 54 and 56. The output shaft of right angle drive mechanism
58 has a second pulley 60 attached thereto which is arranged
substantially perpendicular relative to pulley 56. Tensioner 64 is
fixed to frame 22a and is provided with an adjustable bracket (not
shown) to provide a predetermined tension to belt 62 during
assembly. Tensioner 64 may include a pulley assembly fixed to the
adjustable bracket through a centrally located roller bearing
assembly (not shown).
[0040] Referring to FIGS. 3 and 4, rotation of engine output shaft
50 (FIG. 5A) causes rotation of auger 28 through working device
drive mechanism 65a. Referring to FIG. 4, working device drive
mechanism 65a includes pivot arm 66 having first and second ends 68
and 70 of which end 68 is pivotally attached to frame 22a and
second end 70 is provided with tensioner pulley 74 rotatably
attached thereto. Pivot arm 66 includes notch 72 which receives an
end of tension spring 78; the other end of spring 78 is anchored to
frame portion 77. Belt 79 is engaged with the peripheries of drive
pulley 60 and auger pulley 82. Cable end 81 extends through
aperture 74 in pivot arm 66 and is connected to corresponding cable
assembly 83 to transfer operator movement of control assembly 32
(FIG. 5A) to pivoting movement of pivot arm 66 to rotatably engage
auger 28. As best shown in FIG. 5A, auger pulley 82 is attached to
an axial end of auger 28 and a centrally located auger drive shaft
84 provides support for auger blade 85 (FIG. 1) attached thereto.
Auger 28 includes shaft 84 and blade 85.
[0041] Referring to FIG. 5A, drive mechanism 65a is activated
through operator manipulation of control bail 67 located at second
end 34 of handle portion 30 of implement 20a. When drive mechanism
65a is in a fully disengaged condition (not shown), tensioner
pulley 75 rotatably attached to pivot arm 66 exerts little or no
lateral force on belt 79 through pulley 75 and as a result rotation
of drive pulley 60 has no effect on substantially loose and
stationary belt 62, and hence, auger pulley 82 is not urged to
rotate. In contrast, when the working device drive mechanism 65a is
in an engaged condition, belt 62 is tensioned by pulley 75 (FIGS.
3, 4). Accordingly, rotation of pulley 60 causes rotation of auger
pulley 82 through belt 62 to thereby rotate auger 28.
[0042] Referring to FIG. 5B, second embodiment snow thrower 20b is
shown and includes working device drive mechanism 65b horizontally
oriented and positioned underneath deck 41b of frame 22b (FIG. 1B).
Drive mechanism 65b differs from working device drive mechanism 65a
shown in FIG. 5A by including pivot arm 90 (FIG. 6B) acting on belt
62, which is engaged between power take off pulley 54 and the input
pulley 56 of angle drive 58, through tensioner pulley 98. Referring
to FIG. 6B, working device drive mechanism 65b includes pivot arm
90 having first and second ends 92 and 94 in which first end 92 is
pivotally attached to base portion 96 and pulley 98 rotatably
supported by second end 94 of arm 90. Cable end 81 extends through
aperture 100 in pivot arm 90 to rotate pivot arm 90 and urge
tensioner pulley 98 into engagement with belt 62 in response to
user movement of control member 67 (FIG. 5B) of control assembly
32. It will be understood by those having ordinary skill in the art
that auger pulley 82 is in direct driving engagement with pulley 60
of angle drive mechanism 58 through a predetermined tension
effected on belt 86 by adjustably fixed tensioner pulley 88
attached to frame 22b.
[0043] Referring to FIG. 1A, implement 20a includes access panel
102 which covers and encloses cavity 104 (FIG. 4) containing drive
mechanism 65a. Panel 102 is attached by fasteners 106 extended
through spaced apart holes provided along periphery 110 of access
panel 102. Walk-behind implement 20a also includes snow deflection
chute positioner mechanism 112 having crank handle 114 attached to
shaft 116. Shaft 116 is supported by handle cross member 118
through support bracket 120 mounted to cross member 118. Crank
plate 122 is secured to axial end 124 of shaft 116 and crank handle
114 is attached to crank plate 122. Crank handle 114 is offset
relative to shaft 116 to provide an adequate lever arm length such
that shaft 116 may be rotated by an operator with little to
moderate effort. As is customary, rotation of handle 114 causes
rotation of deflection chute 38 to accordingly throw snow in a
direction selected by an operator positioning positioner mechanism
112.
[0044] As best shown in FIG. 5A, rotation of engine output shaft 50
is transferred to rotation of wheels 24 through wheel drive
mechanism 126. Wheel drive mechanism 126 includes first and second
transmission modules 128 and 130 having respective drive shafts 131
and 133. Transmission modules 128 and 130 are each similar to
commercially-available Model 301 transmissions manufactured by
Tecumseh Products Company. Pulleys 132 and 134 are respectively
keyed to driveshafts 131, 133. Referring to FIG. 7, belt 136 is
engaged with a portion of a periphery of wheel drive pulley 52, and
is additionally engaged about a portion of peripheries of pulleys
132 and 134 of first and second transmission modules 128 and 130. A
fixed tensioner pulley 138 is rotatably mounted to frame 22a and
positioned between wheel drive pulley 52 and pulley 132 of first
transmission module 128. Tensioner pulley 138 is adjustably fixed
such that a predetermined tension may be exacted on belt 136 during
assembly of walk-behind implement 20a. First and second
transmission modules 128 and 130 share a common axle 142 and axle
142 includes first and second ends each of which include a gear 144
attached thereto (FIG. 8).
[0045] First and second transmission modules 128 and 130 are
respectively provided with actuator levers 148 and 150 each of
which, when rotated, provides engagement of drive shaft 131 or 133
with drive engaging wheels 24 through the respective transmission
module. Actuator levers 148 and 150 are alternately, rotatably
displaced through operator manipulation of control assembly 32 as
hereinafter described. It may be seen that rotation of axle 142
causes rotation of gears 144 which are meshed with a pair of wheel
gears 146 fixed to respective hubs 147 of wheels 24 (FIG. 8).
[0046] Referring to FIG. 8, first transmission module 128, which is
similar to second transmission module 130, includes housing 152
having sealed internal cavity 154 containing lubrication fluid
(e.g. oil) therein. Referring to FIGS. 9-10, a shaft seal (not
shown), such as an O-ring seal, for example, is captured within a
recessed portion of housing half 158 to seal surface 160 of drive
shaft 131 and sealably encloses cavity 154 of housing 152. A pair
of seals 162, 164 provide a lubrication barrier between axle 142
and housing 152 and a seal is included in each respective sleeve
assembly 166, 168 to prevent oil within cavity 154 from escaping
housing 152. Housing seal 170 is provided between housing halves
158 and 159 to seal housing cavity 154 at interface 172 (FIG. 9).
Oil fill plug (not shown) is removably attached to upper housing
half 158 to allow for introduction or removal of oil into housing
152.
[0047] Transmission module 128 includes external actuator lever 148
which, when rotated by an operator through cable linkage, causes
the transmission drive shaft 131 to become operatively coupled with
axle 142. Referring to FIG. 9, drive shaft 131 includes right hand
worm portion 176, to cause forward rotation of axle 142. Worm
portion 176 is located on outer surface 160 of drive shaft 131, and
is intermeshed with right hand worm gear 178. Ball bearing
assemblies 180, 182 are respectively fitted within housing halves
158 and 159 to rotatably support drive shaft 131. Ball bearing
assemblies 155, 156 are captured between housing halves 158, 159 to
rotatably support axle 142. Housing halves 158, 159 are fastened
together by screws 157. A pair of cone clutches 184, 186 are
rotationally fixed on axle 142 by having notches 188, 190 provided
therein and engaged with Woodruff key 192. Woodruff key 192 is
engaged within notch 194 machined into axle 142 by a broaching
operation, for example. Cone clutches 184, 186 respectively include
frustoconical surfaces 196, 198 which engage complementary
frustoconical surfaces 200, 202 provided on lateral sides 204, 206
of worm gear 178 (FIG. 10). Washers 208, 210 are in contact with
respective butt ends 212, 214 of cone clutches 184, 186 and thrust
bearings 216, 218 contact respective washers 208, 210. Washers 220,
222 contact respective thrust bearings 216, 218. Additionally,
spacers 224, 226 are positioned on outermost lateral surfaces of
washers 220, 222 and an actuator plate 228 is positioned
intermediate spacer 226 and sleeve assembly 168. Actuator plate 228
is engaged by cam portion 230 of actuator rod 232 as rod 232 is
selectively rotated by an operator through, for example, cable
linkage attached to actuator lever 148.
[0048] In operation, an axial force, provided by actuator plate 228
due to selective rotation of actuator lever 148 and actuator rod
232, is transmitted to cone clutches 184, 186, causing
frustoconical surfaces 196, 198 of respective cone clutches 184,
186 to respectively engage frustoconical surfaces 200, 202 of worm
gear 178. Rotation of actuator rod 232 operatively engages worm
gear 178 and axle 142, through the clutch/worm gear interface, and
axle 142 is thus driven by rotating drive shaft 131. In a fully
engaged condition, surfaces 196, 198 of the cone clutches and
surfaces 200, 202 of the worm gear simultaneously rotate having
little or no slippage occurring therebetween. A degree of slippage
initially occurs between surfaces 196, 198 of cone clutches 186,
188 and surfaces 200, 202 of worm gear 178 during engagement
thereof, resulting in a "soft" engagement therebetween. When cone
clutches 186, 188 are fully engaged with worm gear 178, the speed
of axle 142, relative to the speed of drive shaft 131, is directly
reduced through the engagement of worm gear 178 and worm portion
176 to produce, for example, an axle speed nine times less than the
speed of drive shaft 131.
[0049] Second transmission module 130 differs from second
transmission module 128 by including an oppositely configured, left
hand worm portion 233 which meshes with corresponding oppositely
machined gear teeth of left hand worm gear 234 (FIG. 8). Thus, the
drive assembly in operation provides alternate clutching engagement
between first transmission module 128, resulting in reverse
movement of implement 20a, and second transmission module 130,
resulting in forward motion of implement 20a.
[0050] Referring to FIG. 11, it may be seen that engagement or
disengagement of auger 28 (FIG. 1A) may be controlled by an
operator manually pivoting U-shaped control lever 67 of control
assembly 32. Lever 67 includes a grip cover 236 (FIG. 13) which
extends along the length of elongate handle portion 237. A pair of
side rails 238, 240 extend generally, perpendicularly relative to
handle portion 237, and are each provided with first ends, which
connect to the handle portion, and second ends which form pivot
pins 242 and 244 (FIG. 12) which extend through respective holes
246 (FIG. 13) and 248 (FIG. 12) within handle 30.
[0051] As best shown in FIG. 13, lever 67 is also provided with
linkage member 250 which includes cable post 252 at one end and a
hook-shaped stop portion 254 at the opposite end. A portion 256 of
linkage member 250 overlays side rail 238 and is attached to side
rail through welding or brazing, for example. Cable end 260 is
rotatably supported by cable post 252 of linkage member 250 and is
attached to cable 258 of cable assembly 83 (FIGS. 4, 13). Cable
assembly 83 includes end 81 attached to auger pivot arm 66 and
second end 260 attached to cable post 252 of working device
actuation lever 67. Sheath 261 (FIGS. 4, 13) extends along at least
a portion of the length of cable 258.
[0052] Referring to FIG. 11, it may be seen that control assembly
32 includes oblong hoop-shaped wheel control member 262 which
includes forward bail 264 and reverse bail 266. The forward and
reverse bails respectively include elongate handle portions 267 and
268. Forward bail 264 includes a pair of side rails 269 and reverse
bail 266 includes a pair of side rails 270. Side rails 269 of
forward bail 264 are respectively attached to each end of elongate
handle portion 267 and extend substantially perpendicularly
therefrom toward reverse bail 266. Reverse bail 266 is generally a
mirror image of forward bail 264 and includes side rails 270
attached at each end which extend substantially perpendicularly
therefrom and toward forward bail 264. Side rails 269 join
respective side rails 270 through a pair of welds, for example, and
a pair of pivot posts 272 and 274 extend outwardly from the side
rail joints. Pivot posts 272, 274 are generally parallel with
elongate handle portions 267 and 268 of forward and reverse bails
264 and 266. A pair of opposed holes 276 (FIG. 13) and 278 (FIG.
12) are provided in handle 30 and respectively receive pivot post
272 (FIG. 13) and 274 (FIG. 12). As best seen in FIG. 12, swivel
plate 281 is fixed to pivot post 274 and is located between side
rails 269, 270 and handle 30. Swivel plate 281 includes first and
second through holes 283 and 285, and respectively rotatable
therein are ends 280 and 282 of cables 286 and 294.
[0053] Referring to FIG. 7, forward cable assembly 284 is provided
with cable 286 which is covered at least partially along its length
by sheath 288 and includes rear cable end 280, connected to swivel
plate 281 (FIG. 12) and front cable end 290 connected to actuator
lever 150 of second transmission module 130. Reverse cable assembly
292 includes cable 294 having rear end 282 connected to swivel
plate 281 and front end 298 attached to actuator lever 148 of first
transmission module 128. Cable sheath 296 of reverse cable assembly
292 extends at least partially along the length of cable 294. As is
customary, cable clamps 300 (FIGS. 11-13) may be placed in several
discrete locations to ensure that each cable assembly is closely
positioned, and secured, along portions of the handle.
[0054] Referring to FIGS. 14-18, the operation of implement 20a
will now be described. FIG. 14 illustrates a neutral condition
wherein the working device and wheel drive mechanisms 65a, 126 are
in a neutral or non-activated condition. Accordingly, forward and
reverse bails 264, 266 of wheel control member 262 are
substantially equally positioned on each side of handle 30.
Notably, in this position, each elongate handle portion 267 and 268
of forward and reverse bails 264, 266 is substantially equally
spaced from an elongate push portion of handle 30. Extension spring
271 (FIG. 9) is attached to actuator lever 248 to cause reverse
bail 266 to return to the neutral position when released.
Similarly, a substantially identical extension spring 273 is
attached to actuator lever 150 of second transmission module 130 to
cause forward bail 264 to return to a neutral position. It may be
seen that working device activation lever 67 extends significantly
outward from handle 30 and is biased into position by extension
spring 78 acting on pivot arm 66 (FIG. 4).
[0055] FIG. 15 represents an auger activation and wheel drive
mechanism deactivation condition. It may be seen that working
device activation lever 67 is swung downwardly, toward handle 30,
by an operator, such that portion 237 of lever 67 is adjacently
positioned to handle 30 and working device drive mechanism 65a is
accordingly engaged. Accordingly, as lever 67 is swung toward
handle 30, cable 258 is moved by cable post 252 (FIG. 13) of
linkage member 250 from a first position corresponding to a neutral
position of the transmission (FIG. 14) to a second position
corresponding to an engaged position of the transmission module
(FIGS. 13, 15).
[0056] Referring to FIG. 16, it may be seen that the working device
activation lever 67 and the wheel control member 262 are both
respectively in engaged positions resulting in rotation of auger 28
and forward movement of implement 20a. The wheel control member
262, in this position, effectuates rotation of operator lever 150
of second transmission module 130 (FIG. 7) to a position in which
clutching engagement and corresponding forward rotation of axle 142
is accomplished. It will be understood by those having ordinary
skill in the art that manipulation of forward bail 264 which
tensions cable 286 of forward cable assembly 284 simultaneously
slackens or loosens of reverse cable 294 of reverse cable assembly
292 such that each first and second transmission module 128 and 130
operate mutually exclusively with respect to one another.
[0057] Referring to FIG. 17, a condition of control assembly 32
corresponding to reverse movement of implement 20a and
non-engagement of auger 28 is shown. It may be seen that reverse
cable 294 of reverse cable assembly 292 is displaced towards handle
30, and simultaneously, forward cable 286 of forward cable assembly
284 is decreased in tension to ensure exclusive actuation of first
transmission module 128. The ability to reverse implement 20a under
power, with the controls positioned as shown in FIG. 17, allows an
operator to expend significantly less effort than would otherwise
be required in pulling the implement backward.
[0058] Referring to FIG. 18, working device activation lever 67 is
fully engaged, and forward bail 264 of wheel control member 262 is
partially engaged, such that wheel control member 262 effectuates
rotation of actuator lever 150 of second transmission module 130
(FIG. 7) to a position in which a degree of slippage occurs between
the complementing frustoconical surfaces of the cone clutches and
the worm gear surfaces during the "soft" engagement thereof. Upon
further movement of forward bail 264 of wheel control member 262,
the complementing frustoconical surfaces of the cone clutches and
worm gear surfaces rotate together, and the implement moves
forward.
[0059] Referring to FIG. 19, a fourth embodiment of a walk-behind
implement is shown which includes a modified control assembly.
Control assembly 32d differs from control assembly 32 illustrated
in FIG. 11 in that swivel plate 281 is eliminated and forward and
reverse cable assemblies 284, 292 are directly attached to forward
and reverse bails 264, 266, respectively. Specifically, rear end
280 of forward cable assembly 284 is pivotally fixed to side rail
269 of forward bail 264, and rear end 282 of reverse cable assembly
292 is pivotally fixed to side rail 270 of reverse bail 266. Rear
cable ends 280, 282 may be swivel joint type ends, for example.
Although shown being positioned at opposite ends of elongate wheel
control member 262d, it is contemplated that forward and reverse
cable assemblies 284, 292, and their associated forward and reverse
cable rear ends 280, 282 may be located at the same end of elongate
wheel control member 262d by being attached to respective side
rails 269, 270 of forward and reverse bails 264, 266.
[0060] It is further contemplated that the wheel control member may
be manipulated such that movement of bail member 266 toward handle
30 (FIG. 17) causes forward movement of implement 20a, and movement
of bail member 264 toward handle 30 (FIG. 16) causes reverse motion
of implement 20a ; that is, cable ends 280, 282 may be reversed
from the positions as described above.
[0061] While this invention has been described as having exemplary
designs, the present invention can be further modified within the
spirit and scope of this disclosure. This application is therefore
intended to cover any variations, uses, or adaptations of the
invention using its general principles. Further, this application
is intended to cover such departures from the present disclosure as
come within known or customary practice in the art to which this
invention pertains and which fall within the limits of the appended
claims.
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