Note: Descriptions are shown in the official language in which they were submitted.
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IMPROVED SYSTEM FOR CONTROLLING THE GROUND SPEED
AND DIRECTION OF TRAVEL OF AN OFF-ROAD VEHICLE
Background of the Invention
The present invention relates to an improved system for
controlling the ground speed of an off-road vehicle and, more
specifically relates to an improved interconnected system for
controlling the ground speed of lawn tractors, lawn and garden
- tractors and front-mount mowers having variable speed
transmissions, such as hydrostatic or continuously variable
transmissions.
It is well known to provide off-road vehicles,
specifically lawn tractors, lawn and garden tractors, and
front-mount mowers with systems for controlling their ground
speed. Typically, variable speed transmissions such as
hydrostatic transmissions or continuously variable
transmissions utilized in off-road vehicles such as those
listed above have used different combinations of hand and foot
controls to select the direction of travel and to control the
relative vehicle speed. Conventional off-road vehicle hand
controls require that the operator remove at least one hand
from the steering wheel to reach a control lever and to move
it to the appropriate location. During the movement of the
operator's hand from the steering wheel to the control lever,
-~ the operator i5 required to interrupt his concentration from
the task he is performing with the vehicle in order to
concentrate on moving his hand control to the proper position.
Thus, with conventional hand controls, there i5 a tendency for
operators to break their roncentration and thereby to reduce
- productivity and operating comfort.
Another conventional system utilized to control the
ground speed of the types of off-road vehicles mentioned above
includes a treadle pedal which is essentially a heel and toe
; forward and reverse ~ontrol mechanism. With the treadle pedal
control system, an operator normally places his foot on the
pedal in such a way that the toe of the operator's foot would
contact one portion of the treadle pedal and the heel would
contact another portion. To drive the vehicle in the forward
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direction, the operator presses his toe forward thereby
raising his heel off of the vehicle foot rest. To change the
move~ent to the direction to reverse or to slow it down, the
operator would increase the pressure on his heel until the
vehicle eventually comes to a complete stop, and then continue
pressing his heel down toward the foot rest in order to
produce vehicle movement in the reverse direction.
The conventional treadle pedal system has proved to have
three significant problems, the first being operator
discomfort which results from the fore-and-aft movement of the
foot and the second, somewhat related to the first, being
difficulty in modulating the vehicle's speed in either the
forward ~r reverse direction because the conventional treadle
pedal design requires that the operator keep his foot on both
the forward control and reverse control portions of the pedal
simultaneously. Additionally, because the operator's leg is
suspended above the foot rest, with the foot located on a
movable pedal without the foot maintaining contact with the
foot rest thereby providing foot stability, vehicle speed
control over rough terrain has proven most difficult.
A third and perhaps the most desirable ground speed
control system developed to date for off-road vehicles is the
dual pedal side-by-side system. The details of this system
are disclosed in U.S. Pat. No. 4,759,417 dated Jul. 26, 1988
issued to Wanie et al and commonly assigned to the assignee of
the present application. However, the side-by-sid~ pedal -
location required the operator to use one foot to operate both
the forward and reverse pedals, and therefore, occasionally
resulted in the wrong pedal being pressed for the direction
the operator intended to have the vehicle move.
5pecifically, in the two pedal side-by-side system, the
two pedals are operated by the right foot. Each of the pedals
when pushed moves through a similar forward arc. The main
distinguishing feature between the reverse speed control pedal
and the forward speed control pedal is that the reverse speed
control pedal is located to the ri~ht of the forward speed
control pedal. Both pedals occasionally re~uire that the
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riyht foot and leg be lifted and the foot placed on the
correct pedal in order to move the vehicle in the desired
direction.
This side-by-side relationship is not as natural for an
operator to relate to forward and reverse as are forward and
reverse position pedals, since the operator moves his foot
through a similar arc for both forward and reverse vehicle
- movement. Consequently, it may sometimes be difficult for an
~- operator to feel which pedal his foot is engaging without
loo~ing.
- An additional problem with present control systems is
that they generally rely on a spring-loaded mechanism to
return the variable speed or hydrostatic transmission to
neutral. Frictional resistance in the lever controls or
pedals and the linkages between the lever control or pedals
and the variable speed transmission which may be caused by
dirt, rust or other impairments, may exceed the force which
the neutral return spring exists on the mechanism.
Accordingly, there is a need for an improved system for
controlling the ground speed and direction of travel of
~- maneuverable off-road vehicles having variable speed
transmissions such as variable speed hydrostatic
transmissions, which allows an operator to know by feel which
direction pedal he is engaging with his foot without looking.
Such a system should improve vehicle operator efficiency in
foot movement, decreasing fatigue, increasing productivity and
comfort. Additionally, it would be desirable to have a foot
pedal control system that provides different engaging areas
for forward and reverse and which allows an operator to
maintain his heel in contact with the vehicle foot rest during
the disengagement of one pedal and engagement of the other.
Summary of the Invention --
The present invention is an improved system for
controlling the ground speed and direction of a maneuverable
off-road vehicle. In each of the preferred embodiments, the
: system of the present invention is illustrated utili~ing a
representative compact utility tractor, a representative lawn
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and garden tractor, and a represen~at5ve front-mount mower,
each having a variable speed transmission such as a
hydrostatic transmission. The system of the present invention
includes an engine operatively connected to a variable speed
transmission and a two pedal direction control system
operatively connected to the variable speed transmission
control shaft for selectively engaging the transmissions so
that the vehicle is operated in either the forward or the
reverse direction. The two pedal direction control system is
arranged on the vehicle relative to each other so that
operator foot movement from each of said pedals respectively
is the same as the desired direction of vehicle movement~
Additionally, the forward pedal is constructed so that it
moves in a forward arc when engaged by an operator and the 15 reverse pedal is constructed so it moves in a rearward arc.
These two different pedal movement arcs provide a different
feel which is readily recognized by an operator.
A further aspect of the present invention includes a
system operatively interconnecting the ground speed control 20 system and the vehicle brake system, for pulling the ~oot
control linkage to neutral when the operator engages the brake
pedal.
Accordingly, objects of the present invention include:
providing a two pedal control system which allows the operator
to differentiate between the forward and reverse pedal~ by
- relati~e pedal position and feel; providing a two pedal
control system which allows the operator to differentiate
between the pedals without looking; providing improved
productivity; providing an improved two pedal control system
whereby an operator moves his toe relative to the vehicle in
the same direction when engaging the desired pedal as the
desired v~hicle direction o~ movement; providing a two pedal
control system which enables an operator to more evenly
modulate vehicle speed during operation; providing a two pedal
control system whereby direction changes are executed by an
operator by simply pivoting his foot at his heel from one
pedal to another; providing a brake ~nd pedal system interlock
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system whereby, when the brake is engaged, the pedal system is
r~turned to the neutral position; providing a system whereby
when the park brake is engaged, the pedals are locked so that
the machine will not move even if the operator should
accidentally engage the pedal while mounting or dismounting
the vehicle; and/or providing a simplified system with a lower
cost in material, manufacturing and assembly than previous
systems.
Other objects and advantages of the invention will be
apparent from the following description, the accompanying
drawings and the appended claims.
Brief Description of the Drawings
FIG. 1 is a partial side view illustrating the
interconnection of a neutral location and return system and a
~5 prior two pedal system utilized in a compact utility tractor;
FIG. 2 is a partial side view of the improved p~dal
system installed on the compact utility tractor of FIG. 1
according to the present invention;
FIG. 3 is a view similar to FIG. 2 illustrating the
relative position of the operator's foot and toe when engaging
; the forward pedal of the pedal system of the present
invention;
FIG. 4 is a perspective view of a representative
conventional lawn and garden tractor;
FIG. 5 is a partial perspective view of the improved two
pedal sy6tem of the present invention installed on a lawn and
garden tractor similar to that of FIG. 4;
FIG. 6 is a partial side view illustrating the
interconnection of the neutral location and return system and ~ :
the improved pedal system of FIG. 5;
FIG. 7 is a partial top view illustrating the
interconnection of the neutral location and return system and
the improved pedal system of FIG. 5;
FIG. 8a is a partial s~de view of the reverse pedal
portion of the improved two pedal system, of FIG. 5
illustrating the lost motion slot;
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FIG~ 8b is a partial top view of the reverse pedal
portion of the improved two pedal system of FIGr~ 5
illustrating the lost motion slot;
FIG. 9 is a side view of a front-mount mower having the
5 improved two pedal system of the present invention installed
- therein;
FIG. 10 is a partial front view in section of the
improved two pedal system of the present invention installed
in the front-mount mower of FIG. 9;
FIG. lla is a partial right-hand side view of the
improved two pedal system brake interconnection system
- installed in the front-mount mower of FIG. 9;
FIG. llb is a partial plan view of the two pedal brake
interconnection system of FIG. lla;
FIG. 12 is a partial side view o~ the brake and two pedal
system interconnection of FIGS. lla and llb;
FIG. 13 is a partial top sectional view of the improved
system of FIG. 12; and
FIG. 14 is a partial rear view illustrating the neutral
location and return system installed on the front-mount mower
of FIG. 9.
Detailed Description of a First Embodiment
The ground speed con$rol system for a small compact
utility tractor, generally designated as 50, of the present
invention is illustrated in 2-3. The ground speed control
- system 50 also includes a system 52 for locating the neutral
position of a variable speed transmission and for returning
the transmission to neutral and a forward and reverse
direction foot control pedal system 53. The sys$em shown in
~IG. 1 is generally disclosed in U.S. Pat. No. 4,759,417
issued Jul. 26, 1988 to Wanie et al and assigned to the
assignee of the present application.
As shown in FIG. 1, the forward and reverse pedal system
53 is interconn~cted to the neutral location and return system
- 35 51. The pedal system 53 is utilized to rotate a cam 54
operatively connected to a hydrostatic transmission control
shaft 56.
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The forward and reverse pedal system 53 includes a
forward pedal 58 and a reverse pedal 60, each operatively
connected to a shaft 62. A reverse arm 64 with a flange 66 at
one end and a hub 68 at the other end is operatively connected
to the shaft 62. The hub 68 is conventionally attached to the
end of the shaft 62 remote from the connection of the reverse
pedal 60 to the shaft 62. The attached arm 64 extends above
the shaft 62.
The forward foot pedal 58 is conventionally connected to
a pedal bushing 70 rotatably mounted on the shaft 62. The
bushing 70 has an arm 72 connected thereto and extending below
the shaft 62.
Forward and reverse connecting rods 74, 76 are pivotably
connected to the forward 72 and reverse 64 pedal arms,
respectively, at one end and are both operatively connected to
the respective other ends to a bolt 78 having a spacer
thereon. The bolt 78 is operatively connected to a cam
extension portion 80. Since the forward pedal 58 is connected
to the bushing 70 which is rotatably mounted on the shaft 56,
the ground peed contact system functions due to the location
of the forward connecting rod 74 being connected below the
; shaft 62 and the reverse connecting rod 76 being connected
above the shaft 62. Both rods 74, 76 are connected to the cam
? 54 below the cam's pivot point which i8 about the control
shaft 56. Thus, when one or the other of the pedals 58, 60 ic
depressed, the cam 54 is rotated in opposite directions.
In order to drive a vehicle having the ground speed
control system 50 installed therein in either the forward or
the reverse direction, an operator would depress either the
forward 58 or the reverse 60 pedals. If the operator were to
depress the forward pedal 58, which is rotatably connected to
the shaft 62, the lower arm 72 would rotate clockwise which
would compress the forward connecting rod 74 to the rear which
in turn would rotate the cam 54 about the control shaft 56
clockwise. The roller 82 operatively positioned on a cam
follower 84 moves along the upper surface 86 of a cam V 88
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causing the cam follower 84 to rotate clockwise about its
pivot 90.
As the forward pedal 58 is depressed, the reverse pedal
60 is rotated an equal distance in the opposite direction. If
5 the operator were to remove his foot from the forward pedal
58, a resilient means or spring 92 anchored to the frame 94 by
the adjustable eye bolt 96 would tend to pull the upper flange
98 of the cam follower 84 counterclockwise causing the roller
82 to seek the apex 100 of the cam V, thus returning the
hydrostatic control shaft 56 to the neutral position and the
pedals 58, 60 to the rest position.
In order to propel a vehicle in the reverse direction, an
operator would depress the reverse pedal 60 rotating the shaft
arm 64 which is connected to the reverse connection rod 76
clockwise, which would then rotate the cam 54 counterclockwise
about the control shaft 56 causing the cam follower roller 82
to move along the lower cam V-surface 102 which would also
cause the cam follower 84 to rotate clockwise.
Thus, it can be seen that the forward and reverse pedals
58, 60 operate in tandem, i.e. that displacement of one or the
other in a direction is met by equal displacement of the other
in the oppo~ite direction. The adjustable eye bolt 9~ and
resilient means 92 connected to the cam follower 84 provide
con~tant tension on the cam ~ollower 84 such that upon the
absence of pressure being applied on either pedal 58, 60, the
cam follower 84 is rotated in a counterclockwise direction
forcing the roller 82 attached to the cam follower 84 to seek
the apex 10~ of the cam V 88, thus returning the control shaft
56 to the neutral position.
As can be seen from a close examination of FIGS. 1-3, the
basic construction of the ground speed control system 50 has
not changed except for the reverse pedal 114. Since, in FIG.
1, the pedals 58 and 60 appear quite similar, and when
engaged, travel in the same forward arc, it should be readily
apparent that an operator could be required to :Look at which
pedal is being engaged to insure that the vehic:le would move
in the desired direction. Additionally, as shown in ~IG. 1,
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it can be seen that when moving from one pedal to the other,
some operators were sometimes required to lift their foot off
the foot rest. In fact, the arrangement of FIG. 1 usually
required that some operators have their entire foot out of
engagement with the foot rest when engaging either the forward
or reverse pedal.
As shown in FIGS. 2 and 3, the reverse pedal of FIG. 1
has been relocated so that the portion thereby which is
engaged by the operator has been moved from in i~ront of the
foot rest to a position coming through the foot rest 104 at a
location closer to the rear of the vehicle. The. connecting
member 108 between the pedal 114 and the shaft ~2 has been
rerouted through the opening 106 in the foot rest 1~4 and a
bracket 110 for receiving a pivoting shaft 112 has been
operatively connected to the top surface of the foot rest 104
perpendicular to the shaft 62 (see FIG. 1). A new reverse
pedal 114 has been pivotally connected to the shaft 62 so that
it pivots counterclockwise about the shaft 112, down and away
from the operator's foot.
As shown in FIG. 3, an operator engages the forward pedal
58 with the toe 48 of his foot 116 while maintaining his heel
120 in contact with the foot rest 104. As with the forward
pedal 58 of FIG. 1, the member 122 connected to the shaft 62
has moved an equal distance in the opposite direction of the
pedal 114. If the operator were to want to come to a stop and
then back the vehicle up, he would release the pressure on the
pedal 58 with his toe at which time the transmission would
return to neutral. He would then pivot his toe toward the new
reverse pedal 114 preferably maintaining his heel in contact
with the foot rest. Once the vehicle came to a stop, the
operator would press down with his toe onto the new reverse
pedal 114, thereby moving the vehicle rearwardly.
The new reverse pedal 114 is constructed so that if the
operator inadverten~ly presses forward on the reverse pedal
114 with his foot in the same position he uses to depress the
forward pedal 58 ~i.e. he believes he is engaging the forward
pedal), no ~ehicle movement would result because the operator
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must rotate his foot about his heel to the rear of the vehicle
and then press down on the reverse pedal 114. This requires
the operator to move his foot through a rearward arc.
Specifically, as seen in FIG. 3, to move the vehicle in the
forward direction, the operator pushes forward with his toe
and the pedal 58 moves in a forward arc. On the other hand,
if the operator were to enyage the rear pedal 114 and attempt
to press forward, his toe would contact the pivotable shaft
112 and the bracket 110 and would not move member 108 and,
thus, would not rotate the shaft 62.
Another important feature of the relative construction of
the two foot pedals of the present invention is the relative
movement of the operator's toe when engaging the pedals. When
the operator wants the vehicle to go forward, he moves his toe
forward. Specifically, he engages the pedal with his toe and
moves his toe forward. When the operator wants the vehicle to
go in reverse, he moves his toe rearward and engages the pedal
and presses down. Thus, with the relative location of the two
pedals of the present invention, it is more difficult for the
2~ operator to be confused when engaging either the forward or
the reverse pedal because, to go in the forward direction, he
must move his toe forward and then press forward and when he
wants to go in the reverse direction he must move his toe
rearward and then press down. These are two different and
distinct motions which result in two different and distinct
"feels".
Detailed Descri~tion of a Second Embodiment
Referring now to the drawings and specifically to FIGS.
5-8, there is illustrated a second embodiment incorporating
the improved ground speed and direction ~ontrol system of the
present invention, generally indicated as 200, installed on a
representative lawn and garden tractor 202.
FIG. 4 illustrates a representative lawn and garden
tractor 202 incorporating a hand operated lever ground speed
control system 206 installed thereon. As shown in FIG. 4, the
representative lawn and garden tractor 202 consists of a frame
208, a front axle 210 and a rear axle 212. Two front wheels
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214, 216 are mounted on the axle 210 and two rear wheels 218,
220 are mounted on the rear axle 212. A fender deck 222 is
mounted on the frame over the rear axle and includes a pair of
foot rests (only one shown) 224. An operator's station 230
which includes a seat 232, a steering wheel 234 and a hand
operat~d direction control lever 236 is operatively positioned
on the vehicle 202. The direction control lever 236 is
operatively connected to the variable speed transmission (not
shown). The typical lawn and garden tractor 202 also includes
an engine (not shown) and a radiator (not shown) if the engine
i6 liquid cooled, both enclosed within a hood 238.
As shown in FIGS. 5-8, the improved ground speed and
direction control system 200 for the representative lawn and
garden tractor 202 is illustrated. The ground speed and
lS direction control system 200 includes a system 240 for
establishing a neutral position and for returning the
transmission to the neutral position and a forward and reverse
direction control foot pedal system 242. An illustrative
embodiment of the neutral location and return system 240
comprises a cam 244 having a Y-portion 246 connected a
transmission control shaft 248 and a cam follower 250
pivotally connected to the vehicle.
The cam 2~4 connection to the transmission control shaft
248 serves a~ the cam 244 pivot. The cam 244 has a connecting
portion 252 which is connected to a secondary pivot member 25
which is operatively connected to the vehicle frame 208.
The cam follower 250 has a roller means or roller 256
rotatably connected thereto for interacting with the ~-portion
246 of the cam 244. The cam follower 250 is preferably
pivotally connected to the transmission at one end and to
resilient means or a spring 258 at the other.
During operation, the Gam 244 is operatively connected to
the control shaft 248 and pivots about that connection point.
The roller 256 is attached to the cam follower 250 and engages
the cam V 246. The roller 256 moves along either leg 260, 262
of the V 246 depending upon which way the cam 244 is rotated.
The cam's rotation causes the roller 256 to move from the V- -
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apex 264 which in turn causes the cam follower 250 to rotate
about an eccentric 266. This rotation stretches the resilient
means or spring 258. Upon release of the force causing
rotation of the cam, the spring 258 will bias the cam follower
250 towards the cam 244 moving the roller 256 into the apex
264 of the cam V 246.
The forward and reverse pedal system 242 comprises a
forward pedal 270 which is connected to a first shaft 274 and
a reverse pedal 272 which is operatively connected to a second
shaft 276. The two shafts 274, 276 are located approximately
parallel to one another with the second shaft 276 being
located more remote from the neutral location and position
system 240 than the fir~t shaft 274.
The first pedal 270 is operatively connected to one side
277 of a connection means or U-shaped bracket 278 which pivots
about the first shaft 274. The other side 279 of the U-shaped
bracket 278 is operatively connected to one end 280 of a strap
282 which also pivots about the first shaft 274. The other
end 284 of the strap 282 is operatively connected to the
secondary pivot member 254 by an elongated member 282.
The secondary pivot member 254 preferably takes the form
of an elongated member which is pivotably connected to the
vehicle's frame 208 in the middle thereof and is connected to
the elongated linkage means 282 at it~ one end 290 and to the
cam 244 having the V-shaped profile 246 at its other end 292.
The reverse pedal 272 is operatively positioned on the
foot rest 224 and is operatively connected to one end 294 of
the second shaft 276. At the other end 296 of the second
shaft 276, a first link 298 is securely connected to the shaft
276. The first link 298 is connected to the second sha~t 276
so that it moves with the shaft when the shaft 276 is rotated
by engaging the reverse control pedal 272. A second link 300
is pivotably connected to the first link 298 and to the strap
284 by fastener 302.
In order to drive the vehicle in either the forward or
reverse directions, ~n operator would engage either the
forward 270 or reYerse 272 control pedalsO If ~the operator
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were to engage the forward pedal 270, which rotates about the
first shaft 274, the U-bracket 278 would rotate clockwise
thereabout. This rotation would in turn rotate the strap 2B4
clockwise moving the connection linkage 282 forward toward the
forward control pedal 270. Once the control linkage 282 moves
forward, the secondary pivot member 254 would pivot clockwise
causing the cam 244 to rotate clockwise about the control
shaft 248 thereby moving the roller 256 out of the apex 264 of
the V-profile 246.
As the forward pedal 270 i6 engaged, the reverse pedal
272 iB normally rotated an equal distance in the opposite
direction. If the operator were to remove his foot from the
forward pedal, the neutral return spring 258 would pull the
cam follower 250 clockwise causing the roller 256 to seek the
apex 264 of the cam V 246, thus returning the control shaft
248 to the neutral position and the pedals to the rest
position.
In order to drive the vehicle in the reverse direction,
the operator would rotate his foot keeping his heel
maintaining contact with the foot rest 224 to the right and
rearwardly to engage the reverse foot pedal 272. Downward
pressure on the reverse foot pedal would rotate the second
shaft 276 counterclockwise, which in turn, would rotate the
first link 298 counterclockwise thereby moving the second link
300 rearward causing the strap 284 to rotate counterclockwise
a~out the first shaft 274. This strap rotation pushes the
connection linkage 282 towards the transmission rotating the
secondary pivot member 254, causing it to rotate
counterclockwi~e, thereby rotating the cam 244 clockwise about
the control shaft 248.
As shown in FIGS. 8a and 8b, the second link 300 of the
reverse pedal system ha~ a lo~t motion slot 304 formed
therein. The first link ~98 is connected to the second link
300 by a pin 306 which fits in the lost motion slot 304. The
lost motion slot 304 is utilized in the event that the reverse
pedal 27~ is actuated in the wrong direction (clockwise) and
will then prevent the reverse pedal 272 from accuating the
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forward pedal 270, thereby moving the vehicle in the wrong
direction. As shown in FIG. 8b, a spring 308 i9 connected
between the second shaft 276 and the second link 300 to bias
the link 300 to the normal at rest position.
As can be clearly seen with reference to FIG. 5, if an
operator were to have his heel contacting the foot rest 224
and his toe on the forward control pedal 270 in order to move
the vehicle in a forward direction, he would, move his toe
forward. If the operator were to want to change directions
and move the vehicle in reverse, he would, with his heel still
contacting the foot rest 224, move his toe rearward, thereby
allowing the forward control pedal to move towards him and,
after the vehicle came to a stop or while it was decelerating
and after disengaging the forward pedal, he would rotate his
toe, with his heel preferably still engaging the foot rest,
outwardly and rearwardly and then move his toe down tc engage
the reverse control pedal 272. With the illustrated
construction of the improved two pedal control system 242, an
operator is required to move his toe when engaging the desired
pedal in the same direction as that in which he desires the
i vehicle to go, thereby significantly reducing operator
direction selection errors.
Detailed Description of a Third Embodiment
- An improved ground speed and direction control system 400
~or a small front-mount mower 402 is illustrated in FIGS. 9-
14. The representative front-mount ~ower 402 illustrated
includes a frame 404, a front axle 406 having two front
driving wheels 408 (only one shown) and a single rear wheel
410. A platform 412 is mounted on the frame 404 and includes
a pair of foot rests 414 (only one shown~. An operator's
station 4 0 is operatively positioned on the vehicle and
includes a seat 422 and a steering wheel 42~. The front-mount
mower 402 is powered by an engine transaxle combination 426
located under the vehicle operator station 420 and enclosed by
hood 428.
The ground speed control and direction system 400
includes, among other systems, the following subsystems: a
14
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system 430 for locating an accurate neutral position (FIG. 14)
and for returning the transmission to the neutral position; a
forward and reverse direction foot pedal system 432 ~FIGS. 10
and 13); a brake system 434 interconnected with the foot
control system 432 (FIGS. lla, llb, 12 and 13); and a park
brake system 436 interconnected with the brake system 434 and
the pedal control system 432 (FIG. lla).
As shown in FIG. 14, the neutral position location and
return system 430 comprises connection linkage or cable 438
designed to control a control shaft 440 of a variable speed
transaxle 439. The neutral location and return system 430
utilized with the small front-mount mower 402 is similar to
the two systems disclosed within this application and to those
disclosed in U.S. Pat. No. 4,759,417, issued Jul. 26, 1988 to
Wanie et al, the disclosure of which is hereby incorporated by
reference.
The system 400 basically comprises a cam 442 having a V-
shaped notch 444 formed therein. A cam follower 446 having a
roller 448 operatiYely positioned thereon for interaction with
the cam 442. The cam follower 446 is biased by a resilient or
spring means 447 so that when the forces cause the roller 448
to interact with either of the cam surfaces 452, 454, the
resilient means returns the roller 448 to the Y-notch 444.
The cam 442 is adjusted so that the V-notch 444 corresponds to
the transmission neutral position when the roller 44~ is
positioned therein. The linkage 438, in this particular case
a control cable, interconnects the cam 442 to the forward and
reverse direction control pedal system 432.
As shown in FIGS. 9-10 and 12, the forward and reverse
direction foot pedal system 432 comprises a forward pedal 456
including a pad 458 and an arm 460. The arm 460 is pivotably -~
operatively connected to a first shaft 462. A U-shaped
bracket 464 has one portion 466 of the U-me~ber 464 connected
to the arm ~60 and the other portion 46~ U-member 464
extending to a strap, 470. The strap 470 is rotatably
connected at one end to the first shaft ~62 and at the other
end to the cable linkage means 472 which is operatively ~-
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connected at the other end to the neutral locate and return
system 430 and the variable speed transaxle 439 by the cable
438.
A reverse pedal 474 is connected to a second shaft 476,
S positioned parallel to and more forwardly on the vehicle than
the first shaft 462. A first link 478 having a pin 480
operatively connected thereto is securely connected to the
other end of the second shaft 476. A second link 482 having a
lost motion slot 484 formed in one end and being operatively
connected by pin 518 to the strap 470 at the other end,
interconnects the first link 478 with the strap 470. The
second link 482 is connected to the strap 470 at a position
intermediate the two ends of strap 470~
In order to drive the front-mount mower 402 in either the
forward or reverse directions, an operator would engage either
the forward or the reverse pedals. If the operator were to
engage the forward pedal 456, the arm 460 with the U-shaped
member 464 connected thereto would rotate clockwise about the
first shaft 462. This would rotate the strap 470 clockwise
about the first shaft 462, pulling the cable 438 connected to
the other end of the strap 470 forward. At the other end of
the cable, the roller 448 (see FIG. 14) would be forced out of
the V 444 of the cam 442 and would move along the cam surface
452 as disclosed in the above mentioned patent.
As the forward pedal 456 i~ engaged and rotated
clockwise, the second link 482, connected to the reverse pedal
474, would move forward with relationship to the vehicle,
pushing the first link 478 forward causing the pin 480 to move
and the second shaft 476 to rotate clockwise raising the
reverse pedal 474 out of the foot rest 414.
In order to move the vehicle in the reverse direction, an
operator would engage the reverse control pedal 474, thereby
rotating the second shaft 476 counterclockwise which in turn
would rotate the first link 478 counterclockwise. The pin 480
on the first link 478 would then engage the rearward end of
the lost motion slot 484 and move the second link 482 rearward
with respect to the vehicle. This action would rotate the
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strap 470 counterclockwise about the first shaft 462, shifting
the c:able 438 connected to the end of the strap 470 toward the
rear of the vehicle, moving the cam out of engagement with the
roller in the direction opposite to that discussed above.
A spring or resilient means (not shown) is connected
between the pin 480 and the second link 482 for biasing the
reverse pedal to the normal position in case the pedal is
actuated in the wrong direction. If the reverse pedal 474
were to be actuated in the wrong direction (clockwise), then
the lost motion slot 484 in the second link 482 would prevent
the reverse pedal 474 from actuating the forward pedal 456 and
moving the vehicle in the forward direction. Specifically,
this feature is important should debris ~r other foreign
matter become lodged in the reverse pedal mechanism and this
would insure that accidental engagement of the reverse pedal -
474 would not cause an equal rotation of the forward pedal 456
and thereby cause vehicle movement and/or increased vehicle
speed in the forward direction.
Looking now to FIGS. 12 and 13, the interconnection
between the vehicle brake system 434, the park brake system
; 436 with the two pedal forward and reverse pedal control
system 432, and the neutral location and return system 430 is
specifically illustrated.
The vehicle brake system 434 includes a foot brake 486
which has a ~rake pad 488 connected to one end of a brake arm
490. The brake arm 490 is bolted to the U-shaped arm 506 at
its lower portion 508, which arm 506 is fitted over the shaft --
462. The rearward portion 510 of arm 506 carries the brake
pin 512. Looking now to FIGS. lla and 12, an interlock cam
492 is utilized to force the foot pedal cable linkage means
472 to the neutral position when the brake 486 is engaged.
The interlock cam 492 is rotatably connected to the vehicle
frame by an adjustable pivot 494 at one end thereof. The cam
4g2 includes a hook member 496 formed in its other end and a
slot 498 formed intermediate the hook member 4g6 and the
- adjustable pivot 494, Th~ hook member 496 has an extended
portion 500 with a cam surface ~02 formed thereon most remote
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from the adjustable pivot 494. The cam surface 502 is
connected to an opening 504 formed in the interlock cam 492.
The park brake pin 512 engages the slot 498 in the
interlock cam 492. A park brake latch 514 having a hook
member 516 at one end and pivotally connected to the vehicle
at the other end is utilized to lock the vehicle in place with
the brakes applied. The park brake latch 514 is rotata~ly
movable via a park brake lever (not shown) located on the
vehicle fender.
When the brakes are engaged by an operator contacting the
brake pedal 486 with his foot, the brake arm 490 is rotated
towards the front of the vehicle, the arm 490 in turn rotates
the shaft 462 clockwise, and the park brake pin 512 which is
connected to the rearward portion 510 of brake arm 506 forces
the interlock cam 492 upward to engage a roller 518 which is
positioned at the connection between the strap 470 and the
second link member 482. The roller 518 engages the cam
surface 503 of the hook member 496 as the interlock cam 492 is
rotated counterclockwise into engagement. When the vehicle is
moving in the reverse direction, the cam surface 503 engages
the roller 518 as mentioned above. Engagement of the brake
486 forces contact between the hook member 496 and the roller
518, thereby returning the variable speed transaxle to the
neutral position. The neutral position was originally
established with the V-notch in the cam at the transaxle and
was coordinated with the interlock cam 492 position by use of
the adjustable pivot 494.
The park brake latch 514 locks the brakes in the engaged
position. In the engaged position, the hook member 516 of the
park brake latch 514 engages the park brake pin 512, thus
firmiy positioning the roller 512 inside the interlock cam
slot 498 and thus returning the vehicle transmission to the
neutral position.
A brake engaged sensing switch (not shown~ is
interconnected to a conventional seat switch (not shown) for
indicating operator presence and to the vehicle electrical
systPm ~not shown) so that, if an operator were to leave the
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vehicle seat with the parking brake disengaged and the engine
running, the engine would shut-off. This interconnecting
feature allows an operator to dismount the vehicle with the
parking brake engaged and still have the engine remain
operating. Thus, the interconnection of the interlock cam
492, the park brake latch 514 with the improved ground speed
and direction control system 400 provides for safe operation
of the vehicle.
As can be seen from the above, the park brake pin 512
serves a dual function. Specifically, the park brake pin 512
is utilized as the brake 490 is actuated so that the interlock
cam 492 is engaged with the roller 518, thus returning and
locking the forward 456 and reverse ~74 control pedals in
neutral. Additionally, the park brake pin 512 is used by the
1~ park brake latch 514 locking the vehicle brake system in the
full engaged position, thereby returning the transmission to
neutral and to lock the forward and reverse control pedals in -~ -
neutral. The park bra~e pin 512 facilitates simultaneously
1 locking the forward and reverse pedals so that even if they
s 20 were to be accidentally engaged by an operator dismounting or
mounting the vehicle, they would not move to cause the
transmission to be engaged and causing the engaging vehicle to
move. This particular interlock system utilizes a minimum of
~ parts, thereby reducing the potential manufacturing tolerance
-~ 25 build-up between the parts and significantly reducing the cost
~' and time of assembly.
While the forms of apparatus herein described constitute
preferred embodiments of this invention, it is to be
understood that the invention is not limited to these precise
forms of apparatus, and that ~hanges may be made therein
without departing from the scope of the invention, which is
defined in the appended claims.
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