U.S. patent application number 09/730236 was filed with the patent office on 2001-05-03 for power buggy.
Invention is credited to Bengtson, Alan D., Dombek, Gregory S., Jansen, Steven E., Motl, Robert M..
Application Number | 20010000641 09/730236 |
Document ID | / |
Family ID | 22505441 |
Filed Date | 2001-05-03 |
United States Patent
Application |
20010000641 |
Kind Code |
A1 |
Dombek, Gregory S. ; et
al. |
May 3, 2001 |
Power buggy
Abstract
A power buggy is configured to be safe, stable, easy to control,
and comfortable. Frequently-used controls such as dump controls, a
speed control, and a directional control, are located at or very
near handgrips of the operator's handle so as to permit the
operator to control the vehicle without releasing either of the
handgrips. For instance, speed and direction are both controlled by
a bidirectional twist grip forming one of the handgrips. The twist
grip must rotate through a neutral position before changing
directional control from forward to reverse so that an operator
cannot reverse the vehicle's direction of travel without first
rather gradually reducing vehicle speed. Operator comfort is also
enhanced by a fuel tank that shields the operator from the engine.
The fuel tank also has a large capacity while simultaneously
functioning as a support for side shrouds of the vehicle. A
stowable operator's platform is lockable in both its stowed and
operative positions so as to prevent injury to the operator from
unintended platform movement.
Inventors: |
Dombek, Gregory S.;
(Germantown, WI) ; Jansen, Steven E.; (Wild Rose,
WI) ; Bengtson, Alan D.; (Shorewood, WI) ;
Motl, Robert M.; (West Bend, WI) |
Correspondence
Address: |
BOYLE FREDRICKSON ZIOLKOWSKI, S.C.
250 EAST WISCONSIN AVENUE
SUITE 1030
MILWAUKEE
WI
53202
|
Family ID: |
22505441 |
Appl. No.: |
09/730236 |
Filed: |
December 5, 2000 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09730236 |
Dec 5, 2000 |
|
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09143753 |
Aug 31, 1998 |
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6155648 |
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Current U.S.
Class: |
298/7 |
Current CPC
Class: |
B60K 15/03177 20130101;
B60K 23/00 20130101; B60K 15/063 20130101 |
Class at
Publication: |
298/7 |
International
Class: |
B60P 001/00 |
Claims
We claim:
1. A power buggy comprising: (A) a plurality of wheels; (B) a
movable chassis which is supported on said wheels and which has
front and rear end portions; (C) a dumpable article support which
is supported on said front end portion of said chassis; (D) an
internal combustion engine which is supported on said rear end
portion of said chassis and which at least indirectly supplies
motive power to said wheels; (E) a fuel tank which stores fuel for
said engine, said fuel tank being formed from plastic and at least
partially overlying an upper surface of said engine; and (F)
operator's controls which extend upwardly through said fuel tank
and which are accessible by an operator stationed behind said power
buggy.
2. The power buggy as recited in claim 1, wherein said chassis
includes a frame, and further comprising a side shroud having a
lower end portion connected to said frame and an upper end portion
connected to said fuel tank.
3. The power buggy as recited in claim 2, wherein said shroud has
an at least generally vertical body and a flange which forms said
upper end portion of said shroud, which extends inwardly from an
upper end portion of said body, and which is secured to said fuel
tank.
4. The power buggy as defined in claim 3, wherein said fuel tank
has a longitudinally extending lateral edge portion which is of
reduced thickness when compared to a laterally central portion
thereof, and wherein said flange of said shroud is connected to
said edge portion of said fuel tank.
5. The power buggy as defined in claim 4, wherein a
longitudinally-extending groove is formed in an upper surface of
said edge portion of said fuel tank, and wherein said flange of
said shroud has a hook portion which extends into said groove in
said fuel tank to secure said shroud to said fuel tank.
6. The power buggy as defined in claim 1, wherein said fuel tank is
sufficiently long and wide to completely overlie an upper surface
of said internal combustion engine.
Description
CROSS REFERENCE TO A RELATED APPLICATION
1. This application is a continuation of U.S. patent application
Ser. No. 09/143,753, filed Aug. 31, 1998 and entitled "Power
Buggy."
BACKGROUND OF THE INVENTION
2. 1. Field of the Invention
3. The invention relates to load hauling machines and, more
particularly, relates to a "power buggy," i.e., a relatively small,
self-propelled load hauling vehicle having a storage bucket and
operator's controls. The invention additionally relates to a power
buggy designed to maximize operator safety, stability, and
comfort.
4. 2. Discussion of the Related Art
5. Power buggies are well-known light industrial vehicles designed
to haul loads of from a few hundred pounds to a few tons. The
typical power buggy comprises 1) a chassis supported on the ground
via a plurality of wheels, 2) a storage bucket or dumping platform
supported on the front end of the chassis and liftable to dump
loads, and 3) a power source for propelling the vehicle and for
operating other powered equipment on the vehicle. The typical power
buggy is controlled by an operator who is stationed behind the
power buggy and who either walks behind the power buggy or stands
on an operator's platform mounted on the rear end of the chassis.
Controls for the typical power buggy include a steering control
mechanism, a speed control mechanism, an engine kill switch or
similar controller, and dump controls which raise and lower the
bucket. The vehicle is steered by a generally Y-shaped handlebar
having a pair of handgrips. Vehicle propulsion is controlled by a
squeeze lever mounted adjacent one of the handgrips. Power buggies
of this general type are available from Miller, the Morrison
Division of Amida Industries, Inc., the Whiteman Division of Amida
Industries, Inc., and Schroeder Industries.
6. The typical power buggy has several disadvantages impairing
operator comfort and even risking operator injury.
7. For instance, the controls of the typical power buggy are
inconveniently located and/or difficult to operate. As an example,
the squeeze lever used for speed control operates on generally the
same principal as a motorcycle hand brake to the extent that the
operator must simultaneously grasp the handgrip and pull a
spring-loaded lever towards the handgrip. The vehicle is propelled
at a speed proportional to the amount of force applied to the
squeeze lever. The squeezing action is somewhat difficult for the
operator, and prolonged operation of the squeeze lever can result
in operator hand fatigue.
8. Directional control, i.e., shifting between forward and reverse,
is effected by way of a separate shift control lever located remote
from the squeeze lever. The operator must release one of the
handgrips to shift between forward and reverse with resultant risk
of loss of vehicle control. This risk is heightened by the fact
that, because speed control and directional control are
independent, it is possible for an operator to shift the vehicle
while still applying force to the squeeze lever so that the vehicle
reverses its direction of travel abruptly, thereby potentially
causing the operator to lose his/her balance.
9. These problems are exacerbated by the fact that other controls
are similarly relatively inaccessible and/or hard to operate. For
instance, dump controls typically take the form of hand-operated
levers which are spaced a substantial distance from the handgrips
and which therefore require the release of one of the handgrips for
their operation. Some power buggies attempt to alleviate this
problem by supplementing the hand levers with redundant foot
levers. However, operating the foot levers requires the shifting of
the operator's weight to one foot with risk of loss of balance.
10. All of these factors conspire to render the power buggy
relatively difficult to operate with risk of loss of vehicle
control and even operator injury. At the very least, the operator
risks substantial discomfort in operating the machine.
11. Many power buggies are powered either directly or indirectly by
an internal combustion engine which is located at the rear end of
the vehicle in close proximity to the operator. The typical power
buggy lacks any effective device for isolating the operator from
the engine. Operators of these power buggies therefore experience
additional discomfort from the substantial noise, heat, and
vibrations from the engine. The fuel tank certainly does nothing to
alleviate this problem. In fact, the fuel tank typically comprises
a metal tank located in front of the engine and having a relatively
low capacity of no more than 1-2 gallons. This relatively small
fuel tank must be refilled frequently, which requires on-site
storage of fuel with consequent risk of spills.
12. Some power buggies have an operator's platform which extends
rearwardly from the chassis and which permits the operator to stand
on the platform and ride on the power buggy while operating it.
Some of these platforms are movable from a raised, stowed position
in which the platform extends generally vertically to a lowered,
operative position in which the platform extends generally
horizontally. In addition to reducing the length of the machine for
transport, selectively stowing the operator's platform permits the
operator to operate the power buggy by walking along behind it
rather than riding on the platform. Walk-along operation may be a
matter of preference to some operators and is actually quite
desirable when the power buggy is being operated on soft ground or
under other conditions in which the added weight of the operator
could cause the vehicle to leave undesired tracks.
13. The typical operator's platform is not lockable in either its
stowed position or its operative position. It instead relies on
gravity to hold it in its operative position and relies on a spring
mechanism or an over-center arrangement or the like to hold the
platform in its stowed position. This lack of locking capability
may risk operator injury under some circumstances. For instance,
when the vehicle is traveling up a steep hill with the platform in
its stowed position, the force of gravity may overcome the spring
arrangement or over-center arrangement and cause the platform to
fall backwardly on its own accord and injure the operator's legs.
Conversely, if an operator backs into an obstruction while riding
on the platform while it is in its operative position, that
obstruction may force the platform upwardly and throw the operator
from the vehicle or pinch the operator's feet between the platform
and the chassis.
14. The need therefore has arisen to provide a power buggy that can
be operated easily, safely, and comfortably while at the same time
maximizing vehicle stability.
OBJECTS AND SUMMARY OF THE INVENTION
15. A first principal object of the invention is to provide a power
buggy having a speed/directional control mechanism that permits the
operator to control both the speed and direction of vehicle
movement without releasing either of the vehicle's handgrips.
16. Another object of the invention to provide a power buggy that
meets the first principal object and that prevents the operator
from shifting from one direction of movement to another without
reducing vehicle speed.
17. In accordance with a first aspect of the invention, these
objects are achieved by providing a power buggy comprising a
plurality of wheels, a movable chassis which is supported on the
wheels, a bucket which is supported on the chassis, and a motive
power source which is supported on the chassis and which is
selectively and alternatively operable to propel the power buggy in
a forward direction and in a reverse direction, and an operator's
handle. The operator's handle includes a bidirectional twist grip
which is designed to be grasped by a hand of an operator and which
is operatively coupled to the motive power source such that 1)
rotational movement of the twist grip in a first direction from a
neutral position causes the motive power source to propel the power
buggy in the forward direction and 2) rotational movement of the
twist grip in a second direction from the neutral position causes
the motive power source to propel the power buggy in the reverse
direction.
18. Preferably, the twist grip is operatively coupled to the motive
power source such that power buggy speed increases with increased
twist grip rotation in a particular direction through at least most
of the range of twist grip movement in that direction.
19. As a result of this arrangement, vehicle speed and direction
are easily controlled by a single device, and these two controls
are intertwined such that the vehicle must decelerate at least
somewhat gradually before changing directions.
20. In a preferred embodiment, the twist grip is coupled to the
motive power source by a coupling assembly including a cable and
converter which converts rotational movement of the twist grip to
translational movement of the cable.
21. A second principal object of the invention is to provide a
power buggy having controls arranged to maximize operator safety,
stability, and comfort.
22. In accordance with a second aspect of the invention, this
object is achieved by providing a power buggy comprising, a
plurality of wheels, a movable chassis which is supported on the
wheels, a bucket which is supported on the chassis and which can be
raised and lowered to dump loads, and a motive power source which
is supported on the chassis and which is selectively and
alternatively operable to propel the power buggy in a forward
direction and in a reverse direction. The power buggy further
comprises an operator's handle that includes first and second grips
designed to be grasped by an operator's hands, one of the grips
being a twist grip which is operatively coupled to the motive power
source such that 1) rotational movement of the twist grip in a
first direction from a neutral position causes the motive power
source to propel the power buggy in the forward direction and 2)
rotational movement of the twist grip in a second direction from
the neutral position causes the motive power source to propel the
power buggy in the reverse direction. A bucket dump control switch
is located at least in the vicinity of one of the grips so as to
permit the operator to effect directional control, speed control,
and bucket dumping control while holding onto both of the
grips.
23. A third principal object of the invention is to provide a power
buggy having an improved fuel tank.
24. In accordance with still another aspect of the invention, this
object is achieved by providing a power buggy comprising a
plurality of wheels, a movable chassis which is supported on the
wheels, a bucket which is supported on the chassis, an internal
combustion engine which is supported on the chassis and which at
least indirectly supplies motive power to the wheels, and a fuel
tank which stores fuel for the engine. The fuel tank is formed from
plastic and at least partially overlies an upper surface of the
engine and a rear end of the engine so as to significantly reduce
transmission of sounds and vibrations from the engine to an
operator located behind the engine.
25. Preferably, the fuel tank has a storage capacity of at least
ten gallons to negate the need for on-site fuel storage and
transport.
26. The fuel tank also preferably has a longitudinal groove formed
therein which receives a connector flange of a side shroud of the
vehicle. Attachment of the side shroud to the fuel tank in this
manner reduces the support framework requirement for the
vehicle.
27. A fourth principal object of the invention is to provide a
power buggy having a stowable operator's platform that is lockable
in both its stowed position and its operative position so as to
maximize operator safety regardless of whether the operator is
walking behind the power buggy or riding on the platform.
28. In accordance with another aspect of the invention, this object
is achieved by providing a power buggy comprising a plurality of
wheels, a movable chassis which is supported on the wheels, a
bucket which is supported on the chassis in the vicinity of a front
end of the power buggy, manual controls which are located in the
vicinity of a rear end of the power buggy, and a stowable
operator's platform. The operator's platform is supported on the
chassis in the vicinity of the rear end of the power buggy and is
movable between 1) a stowed position in which an operator can walk
along behind the power buggy while operating the controls and 2) an
operative position in which the operator can ride on the operator's
platform while operating the controls. The operator's platform is
lockable in both the stowed position and the operative
position.
29. Preferably, the stowed position is a raised position in which
the operator's platform extends generally vertically and the
operative position is a lowered position in which the operator's
platform extends generally horizontally. In this case, the
operator's platform preferably is mounted on a pivot shaft which
extends laterally with respect to the chassis and which rotatably
journals the operator's platform to a frame mounted on the chassis.
The operator's platform is locked in its raised and lowered
positions by a spring-loaded locking pin assembly which is mounted
on one of the operator's platform and the frame and at least a
portion of which is biased towards holes formed in the other of the
operator's platform and the frame.
30. Other objects, features, and advantages of the invention will
become apparent to those skilled in the art from the following
detailed description and accompanying drawings. It should be
understood, however, that the detailed description and specific
examples, while indicating preferred embodiments of the present
invention, are given by way of illustration and not of limitation.
Many changes and modifications may be made within the scope of the
present invention without departing from the spirit thereof, and
the invention includes all such modifications.
BRIEF DESCRIPTION OF THE DRAWINGS
31. A preferred exemplary embodiment of the invention is
illustrated in the accompanying drawings in which like reference
numerals represent like parts throughout, and in which:
32. FIG. 1 is a side elevation view of a power buggy constructed in
accordance with a preferred embodiment of the invention;
33. FIG. 2 is a top plan view of the power buggy;
34. FIG. 3 is a rear elevation view of the power buggy;
35. FIG. 4 is a partially exploded perspective view of the power
buggy;
36. FIG. 5 is a partially schematic, partially perspective view of
various controls for the power buggy;
37. FIG. 6 is a fragmentary elevation view of a speed/directional
control mechanism of the power buggy;
38. FIG. 7 is a fragmentary end elevation view of the twist grip
and an associated converter of the speed/directional control
mechanism of FIG. 6;
39. FIG. 8 is a fragmentary side elevation view of a portion of the
power buggy including a motive power source and a fuel tank;
40. FIG. 9 is a fragmentary rear end view of the assembly of FIG.
8;
41. FIG. 10 is an enlarged fragmentary sectional view of the
assembly of FIG. 9;
42. FIG. 11 is a perspective view of the fuel tank, viewed from
above;
43. FIG. 12 is a perspective view of the fuel tank, viewed from
below;
44. FIG. 13 is a fragmentary perspective view of an assembly on the
power buggy including an operator's platform and its associated
support structure, showing the operator's platform in its lowered
or operative position;
45. FIG. 14 is a side elevation view of the assembly of FIG.
13;
46. FIG. 15 is a fragmentary plan view of a portion of the assembly
of FIGS. 13 and 14, illustrating locking of the operator's platform
to its associated support structure;
47. FIG. 16 corresponds to FIG. 13 but illustrates the operator's
platform in its stowed or raised position; and
48. FIG. 17 corresponds to FIG. 14 but, like FIG. 16, illustrates
the operator's platform in its stowed or raised position.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
49. 1. Resume
50. Pursuant to the invention, a power buggy is provided that is
safe, stable, easy to control, and comfortable. Frequently-used
controls such as dump controls, a speed control, and a directional
control, are located at or very near handgrips of the operator's
handle so as to permit the operator to control the vehicle without
releasing either of the handgrips. For instance, speed and
direction are both controlled by a bidirectional twist grip forming
one of the handgrips. The twist grip must rotate through a neutral
position before changing directional control from forward to
reverse so that an operator cannot reverse the vehicle's direction
of travel without first rather gradually reducing vehicle speed.
Operator comfort is also enhanced by a fuel tank that shields the
operator from the engine. The fuel tank also has a large capacity
while simultaneously functioning as a support for side shrouds of
the vehicle. A stowable operator's platform is lockable in both its
stowed and operative positions so as to prevent injury to the
operator from unintended platform movement.
51. 2. Power Buggy Overview
52. Referring initially to FIGS. 1-5, a power buggy 20 is
illustrated that is designed to haul loads over relatively short
distances at construction sites and the like and to dump those
loads at desired locations. The major components of the power buggy
20 include 1) a chassis 22 supported on front and rear wheels 24
and 26, 2) a dumpable article support 28 that is supported on the
chassis and that can be selectively raised and lowered to dump
loads stored therein, 3) a motive power source 30, 4) operator's
controls 32, 34, 36, and 38, and 5) a stowable operator's platform
40.
53. The chassis 22 may comprise any suitable metal frame supported
on wheels or rollers. In the present case, the chassis 22 is
supported on front and rear wheels 24 and 26. The front wheels 24
are driven by the motive power source 30. The rear wheels 26 are
steered using a handle 41 having a left handgrip 42 and a right
handgrip 44. The motive power source and other covered components
of the vehicle are bounded from above by a fuel tank 46 (detailed
in Section 4. below) and from the sides by side shrouds 48. The
side shrouds 48 are attached to the fuel tank 46 at their upper
ends as detailed in Section 4. below and are attached to the
chassis 22 at their lower ends in a conventional manner. A front
shroud (not shown) typically also will be connected at its ends to
the side shrouds 48 and at its top to the fuel tank 46.
54. The dumpable article support 28 may comprise any structure
which is capable of supporting articles and of being raised and
lowered to selectively dump articles stored therein or thereon. For
instance, the article support may comprise a platform. In the
illustrated embodiment, the article support comprises a bucket, so
the terms "dumpable article support" and "bucket" will be used
interchangeably for the sake of convenience. The bucket 28
comprises a plastic storage bucket having a maximum capacity of
2500 pounds. The bucket 28 has a front wall 52 which is relatively
low and which is sloped to facilitate dumping. The bucket also has
a rear wall 50 which is relatively high so as to enhance load
carrying capacity and bucket aesthetics. The front end of the
bucket 28 is pivotably mounted on the chassis 22 via a pivot shaft
54. A double acting hydraulic cylinder 56 (FIG. 5) has a cylinder
end attached to the chassis 22 and a rod end attached to a bracket
58 mounted on a laterally-central portion of a bottom surface of
the bucket 28 in the vicinity of the rear end of the bucket 28.
Cylinder extension pivots the bucket 28 about the shaft 54 to dump
loads. The motive power source 30 preferably comprises 1) a
hydraulic pump 60 (FIGS. 5, 6, and 8) and 2) an internal combustion
engine 62 (FIGS. 3, 5, 8, and 9) that is located behind the pump 60
and that supplies power to the pump 60. The engine 62 preferably is
a relatively small four-stroke engine of about 10-15 horsepower.
The engine 62 also supplies electrical power to the various
electronic components of the vehicle 20 by way of an AC charge coil
64 and a DC converter 66, both illustrated in FIG. 5. The AC charge
coil 64 and DC converter 66 eliminate the need for a battery,
thereby reducing the complexity and weight of the power buggy
20.
55. The pump 60 may comprise any pump which can be driven by the
engine 62 to supply pressurized hydraulic fluid to other system
components. As best seen in FIG. 5, the preferred pump 60 is a
hydrostatic pump having 1) an input shaft 68 driven by the engine
62, 2) a fluid inlet 70 connected to a reservoir 72, 3) supply and
return ports 74 and 76 in a charge portion of the pump 60, and 4)
first and second selectively pressurized fluid outlet ports 78 and
80 in a hydrostatic portion of the pump 60. The supply port 74 is
always pressurized during pump operation and is connected to a
valve manifold block 82 (controlled by solenoids 100 and 102 as
detailed in Section 3. below) via a supply line 84. The return port
76 is connected to manifold block 82 via a return line 86 having a
filter 88 disposed therein. First and second wheel motor supply
lines 90 and 92 extend from the outlet ports 78 and 80, through the
valve block 82, and to opposite sides of a pair of hydraulic motors
94 and 96, one of which is associated with each front wheel 24. The
direction of motor rotation and, accordingly, the direction of
front wheel rotation, is controlled by selectively pressurizing
only one of the outlet ports 78 and 80. This selection is achieved
by operation of a control shaft 98 the operation of which is
detailed in Section 3. below.
56. As discussed briefly above, the operator's controls 32, 34, 36,
and 38, fuel tank 46, and operator's platform 40 are all designed
to maximize operator comfort and safety and to achieve other
benefits. Each of these components will be detailed in turn.
57. 3. Operator's Controls
58. Referring particularly to FIG. 5, all primary vehicle functions
are controlled from locations at or very near the handgrips 42 and
44 so that the operator can operate the vehicle 20 without
releasing either handgrip. Specifically, speed and direction are
controlled via a bidirectional twist grip 32 forming a gripping
surface on one of the handgrips (the right handgrip 44 in the
illustrated embodiment). Bucket dumping is controlled by first and
second dump control switches 34 and 36 mounted adjacent one of the
handgrips (the left handgrip 42 in the illustrated embodiment).
Engine shutoff is controlled by a conventional kill switch 38
mounted adjacent one of the handgrips (the right handgrip 44 in the
illustrated embodiment). While the kill switch 38 is conventional,
the dump control switches 34 and 36 and twist grip 32 are not.
These controls will now be described.
59. Still referring to FIG. 5, fluid flow to the cylinder 56
through the valve block 82 is controlled by first and second
solenoids 100 and 102 which, when actuated, control supply and
exhaust of hydraulic fluid to the double acting hydraulic cylinder
56 to extend and retract the cylinder 56 in order to raise and
lower the bucket 28. Electric power to the solenoids 100 and 102 is
controlled by the first and second switches 34 and 36 so that
activation of one switch raises the bucket 28, and activation of
the other switch lowers the bucket. More specifically, depression
of the first switch 34 energizes the first solenoid 100 to
pressurize a supply line 104 for the cylinder end of the cylinder
56, thereby extending the cylinder 56 and raising the bucket 28.
Depression of the second switch 36 energizes the second solenoid
102 to pressurize a supply line 106 for the rod end of the cylinder
56, thereby retracting the cylinder 56 and lowering the bucket
28.
60. Still referring to FIG. 5, and as described briefly above, the
control shaft 98 for the pump 60 normally assumes a neutral
position in which neither of the outlets 78 and 80 is pressurized
and in which the wheel motors 94 and 96 are not supplied with
pressurized hydraulic fluid. Rotation of the control shaft 98 in
one direction causes the pump 60 to supply pressurized fluid to the
line 90 to drive the wheels 24 forwardly. Rotation of the control
shaft 98 in the opposite direction causes the pump 60 to supply
pressurized fluid to the line 92 and drive the wheels 24 in the
reverse direction. This operation constitutes a departure from
typical hydrostatic-pump-driven power buggies which do not actually
change the direction of fluid flow through the pump but which
instead use a control valve to selectively pressurize one of the
two lines. It also should be noted that vehicle speed is
proportional to the magnitude of control shaft rotation from its
neutral position so that the operator can easily control the
vehicle's speed simply by increasing or decreasing magnitude of
control shaft rotation by changing the magnitude of twist grip
rotation as detailed below.
61. The control shaft 98 is operated by a speed/directional control
mechanism which normally holds the control shaft 98 in its neutral
position and which is selectively operable to rotate the control
shaft 98 in either its forward direction or its reverse direction.
Referring to FIGS. 6 and 7, this mechanism includes the twist grip
32, a cable 110, a first converter that converts rotational
movement of the twist grip 32 to translational movement of the
cable 110, and a second converter that converts translational
movement of the cable 110 to rotational movement of the control
shaft 98.
62. The first converter includes a drive gear 112, a driven gear
116, and a pulley 122. The drive gear comprises a bevel gear 112
that is mounted on a common support shaft 114 for the twist grip 32
so as to rotate with the twist grip 32. The driven gear 116 meshes
with the bevel gear 112 and is mounted on a support shaft 118
journaled in a gear housing 120 encasing both gears 112 and 116.
The pulley 122 is formed integrally with the driven gear 116 so as
to rotate with the driven gear 116. The cable 110 rides over the
pulley 122 and is attached at a generally central portion thereof
to a cable ferrule 124 which fits into a slot on the pulley 122. By
this arrangement, rotation of the twist grip 32 and consequent
pulley rotation drives the cable 110 linearly in the direction of
the arrows 126 in FIG. 6.
63. Still referring to FIG. 6, the second converter includes a
swash plate or lever 130 that is coupled to the control shaft 98
and to opposed first and second ends 132 and 134 of the cable 110.
The lever 130 also is biased towards a central or neutral position
of the control shaft 98 so that motive power is not supplied to the
wheels 24 unless the twist grip 32 is rotated. In the illustrated
embodiment, a central portion of the lever 130 is attached to the
control shaft 98, and the first and second ends 132 and 134 of the
cable 110 are attached to opposite ends of the lever 130. More
specifically, each end 132 and 134 of the cable 110 passes from the
cable ferrule 124, passes through a cable adjuster 136, and is
affixed to the respective end portion of the lever 130.
64. First and second return spring assemblies 140 and 141 bias the
lever 130 towards its neutral position. Each return spring assembly
140, 141 extends generally in parallel with an associated cable end
132 or 134 and is located adjacent the associated cable end. Each
return spring assembly 140, 141 includes 1) a spring housing 142,
2) a plunger 144 which extends through the spring housing 142, and
3) a helical return spring 146. The return spring 146 surrounds the
plunger 144, abuts the support bracket 142 at one end, and abuts a
spring seat 148 at its other end so as to bias the plunger 144
towards the lever 130. The effective plunger length and, hence, the
biasing force imposed on the lever 130 by the plunger 144 can be
adjusted by an adjustment knob 150 that forms a distal end of the
plunger 144 and that is threadedly mounted on a rod 152 forming a
near end of the plunger 144. A distal end of this adjustment knob
150 abuts a wear pad 138 mounted on a transverse portion 154 of the
lever 130 extending perpendicularly to a pump arm portion 156 to
which the cable ends 132 and 134 are affixed.
65. In operation, the return spring assemblies 140 and 141 normally
bias the lever 130 and, hence, the control shaft 98 to their
neutral positions so that no motive power is transferred to the
wheels 24. If the operator wishes to propel the vehicle 20 in the
forward direction, he or she simply rotates the twist grip 32
clockwise in the direction of the arrow 156 in FIGS. 5 and 6. This
twisting movement applies tension to the first end 132 of the cable
110 and pivots the lever 130 and control shaft 98 counterclockwise
as seen in FIG. 6. The resultant control shaft rotation causes the
pump 60 to deliver pressurized fluid to the line 90, thereby
driving the wheels 24 in a forward direction at a speed at least
generally proportional to the magnitude of the rotation of the
twist grip 32 and, hence, to the magnitude of movement of the lever
130 and the control shaft 98. Upon release of the twist grip 32 by
the operator, the lever 130 and the control shaft 98 will return to
their neutral positions under the force of the relevant return
spring assembly 140 or 141.
66. It should be apparent from the above that, due to the
relationship between the twist grip 32, the control shaft 98, and
the wheels 24, the operator cannot reverse the direction of vehicle
movement without rather gradually decelerating the vehicle 20.
Instead, the operator must first return the twist grip 32 to its
neutral position, thereby rather gradually decelerating the
vehicle, and then rotate the twist grip 32 in the opposite
direction (see arrow 158 in FIGS. 5 and 6) to reverse the direction
of vehicle movement. Only then can the operator rotate the twist
grip in the direction of arrow 158. This arrangement helps prevent
shocks to the vehicle 20 that otherwise could occur if an operator
were to shift from one direction of movement to the other at or
near full speed.
67. 4. Fuel Tank
68. The fuel tank 46, best seen in FIGS. 1-4 and 8-12, is unusual
in several beneficial respects. First, it is formed from
rotationally molded plastic rather than metal. It therefore has
good sound and vibration damping characteristics and also can
assume a rather convoluted shape. It is also rather large when
compared to fuel tanks traditionally used on power buggies--having
a capacity of 10-15 gallons as opposed to only 1-2 gallons. It also
acts as an attachment surface for the side shrouds 48, thereby
negating the need for additional shroud support framework.
69. An upper surface 160 of the fuel tank 46, best seen in FIGS.
1-4, 8, and 11, is gently curved along its upper surface to enhance
its appearance. As best seen in FIGS. 1 and 2, a front end 162 of
the fuel tank 46 is sloped upwardly and forwardly so as to be
generally parallel with the sloped upper portion of the rear wall
50 of the bucket 28, thereby avoiding interference between the fuel
tank 46 and the bucket 28 and enhancing the aesthetic appearance of
the power buggy 20.
70. A bottom surface 164 of the fuel tank 46, best seen in FIGS. 8,
9, and 12, is configured so as to overlie the upper surface of the
engine 62 and at least some of the rear surface of the engine 62 so
as to shield the operator from heat, noise and vibrations from the
engine 62. Portions of the bottom surface 164 of the fuel tank 46
are concave so as to nest above adjacent portions of the engine 62
and related components, thereby covering the engine 62. In
addition, a pair of L-shaped portions 168, 170 of the fuel tank 46
extend downwardly from the bottom surface 164 at a location behind
the engine 62 to provide additional fuel storage capacity and to
further shield the operator from the engine 62. Lateral segments of
portions 168 and 170 are spaced apart at the rear of the tank 46 to
accommodate an air filter cowling 166 of the engine 62. Portions
168 and 170 also have longitudinal segments that extend forwardly
from the rear of the tank 46 to the shrouds 48 so that much of the
rear end of the engine 62 is effectively encased by the fuel tank
46, thereby further isolating the operator from the heat and noise
of engine operation.
71. Referring now to FIGS. 9-11, longitudinally extending,
generally upwardly facing grooves 172 are molded into the upper
surface 160 of the fuel tank 46 for receiving the side shrouds 48.
As best seen in FIG. 10, each side shroud 48 is located closely
adjacent the fuel tank 46 and includes 1) a body 174 which extends
at least generally vertically along a major portion thereof, and 2)
an upper flange 176 which extends generally downwardly from an
upper edge of the body 174 and into the associated groove 172 in
the fuel tank 46 thereby to secure the shroud 48 to the fuel tank
46. The complementary generally J-shapes of the grooves 172 in the
fuel tank 46 and the mating flanges in the shrouds 48 assure a
relatively tight connection of the shrouds 48 to the fuel tank 46
and inhibit unintended shroud removal.
72. 5. Operator's Platform
73. The operator's platform 40 is designed to permit an operator to
stand on the platform 40 and to ride on the power buggy 20 while
operating the power buggy 20. The operator's platform 40 is also
designed to selectively move out of this operative position to a
stowed position for transport or for permitting the operator to
walk along behind the vehicle 20, if desired. Preferably, the
operator's platform 40 is pivotably mounted on the chassis 22 so as
to be raised and lowered when moving between its stowed position
and its operative position. The preferred operator platform 40 is
illustrated in FIGS. 13-17 and can be seen in its lowered or
operative position in FIGS. 13-15 and its raised or stowed position
in FIGS. 16 and 17. The platform 40 is mounted on the chassis 22
via a support frame and is locked in its stowed and operative
positions by a locking pin assembly 180.
74. The support frame includes first and second laterally opposed
support braces 182 and 184 which may be mounted on the rear end of
the chassis 22 in any conventional manner. Bottom end portions of
the braces 182 and 184 extend rearwardly from the chassis 22
sufficiently far to permit unobstructed pivoting of the platform 40
relative to the chassis 22. The platform 40 includes 1) a
perforated generally planar support plate 186 and 2) first and
second laterally opposed, longitudinally extending support members
188 and 190 on which the support plate 186 is mounted. More
specifically, front and rear support bars 192 and 194 extend
downwardly from the opposite ends of the support plate 186 and are
attached to the support members 188 and 190. Each of the support
members 188 and 190 preferably takes the form of an inverted U the
center leg of which abuts the front and rear support bars 192 and
194. Mounting brackets 196 and 198 are welded or otherwise affixed
to cantilevered ends of the support members 188 and 190 extending
beyond the front support bar 192. A pivot shaft 200 extends through
the mounting brackets 196 and 198 at a location in front of the
support plate 186 and has opposite ends supported on the first and
second support braces 182 and 184 of the frame so as to permit
pivoting of the support platform 40 relative to the chassis 22.
First and second holes 202 and 204 are formed in each of the
mounting brackets 196 and 198 for receiving a plunger of the
associated locking pin assembly 180 as detailed below. A front end
portion of each of the mounting brackets 196 and 198 extends above
the associated support member 188, 190 to present a raised surface
206, 208 as best seen in FIGS. 13 and 14. A stop member, taking the
form of an inverted U-shaped stop channel 210, extends laterally
with respect to the chassis 22 at a location above the pivot shaft
200 and is attached at its opposite ends to the inner surfaces of
the support braces 182 and 184. The bottom surface of the stop
channel 210 abuts the raised surfaces 206 and 208 of the mounting
brackets 196 and 198 when the operator's platform 40 is in its
operative position to prevent pivoting of the platform 40 beyond
that position.
75. The locking pin assembly 180, best seen in FIG. 15 includes a
plunger guide 212, a plunger 214, and a spring 216. The plunger
guide includes an L-shaped member having 1) a lateral leg 218
affixed to the outer surface of the support brace 182 and 2) a
longitudinal leg 220 extending rearwardly from the lateral leg 218.
The plunger 214 extends through a hole in the longitudinal leg 220
of the plunger guide 212, through a mating hole in the support
brace 182, and towards the mounting bracket 196 for the operator's
platform 40. The spring 216 surrounds the plunger 214 and rests on
the plunger guide 212 at its outer end and on a plunger-mounted
spring seat 222 at its inner end so as to bias the plunger 214
towards the mounting bracket 196. The first and second holes 202
and 204 in the mounting bracket 196 are spaced such that the
plunger 214 is aligned with the first hole 202 when the platform 40
is in its operative position and with the second hole 204 when the
platform 40 is in its stowed position.
76. In operation, the operator will typically stand on the
operator's platform 40 while operating the power buggy 20, with the
operator's platform 40 being locked in the operative position of
FIGS. 13-15 by extension of the plunger 214 into the first hole 202
in the mounting bracket 196. This locking action prevents the
operator's platform 40 from pivoting upwardly should the power
buggy 20 back into an obstruction such as a curb or a hillside.
Contact between the raised surfaces 206 and 208 of the mounting
brackets 196 and 198 and the bottom surface of the stop channel 210
helps assure stability by distributing the operator's weight
between the pivot shaft 200 and the stop channel 210.
77. Should the operator wish to stow the platform 40 either to
prepare the power buggy 20 for transport or to permit the operator
to walk along behind the power buggy 20 during operation, he or she
simply retracts the plunger 214 by grasping a ring 224 on the end
of the plunger 214 and pulling the plunger 214 out of the first
hole 202 against the force of the return spring 216. The operator
then pivots the platform 40 to its raised position of FIGS. 16 and
17 and releases the ring 224 so that the plunger 214 is driven into
the second hole 204 by the return spring 216, thereby locking the
platform 40 in its raised position.
78. Many changes and modifications could be made to the invention
without departing from the spirit thereof. The scope of some of
those changes is discussed above. The scope of other changes will
become apparent from the appended claims.
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