Motorized dumping vehicle

A motorized dump-type vehicle is provided having a chassis frame, a gasoline engine mounted on said frame, a dump container pivotally mounted on the front of said frame and a hydraulic system enabling said container to be raised and lowered by a hydraulic cylinder and said vehicle to be driven in either forward or reverse directions and braked by hydraulic drive motors. The hydraulic fluid is cooled by an oil reservoir tank forming a structural part of the frame and positioned such that heat from the hydraulic fluid can dissipate itself in the container and its contents.

DESCRIPTION 
Technical Field 
The invention relates to a motorized load-carrying vehicle with a 
load-carrying pan tipped by power-operated means on the vehicle. 
BACKGROUND ART 
Concrete construction and other work requiring on-the-job transport of 
heavy materials from one location to another has brought about the 
development of a variety of relatively-small, load-carrying vehicles 
capable of moving on the job site with relatively small but often very 
heavy loads of material. For example, a frequent need is to load a 
quantity of concrete at a first location, transport such concrete to a 
second location and then dump the contents for spreading and screeding 
operations at the second location. In concrete work such vehicles are 
often referred to as a "concrete buggy". They may also be referred to as a 
dump truck or power-driven wheelbarrow. Some of such vehicles are of the 
walk-behind type while others are of the step or seat-riding type. The 
load which is carried by a container called a "skip", "hopper", "pan", or 
"dump box" is conventionally raised and lowered by a hydraulic piston as 
in U.S. Pat. Nos. 2,424,670 or 2,427,132. A front pair of single or dual 
wheels is conventionally driven by a differential and transmission as in 
U.S. Pat. No. 2,427,132. In the three-wheel-type vehicle, a single or dual 
wheel supports the rear of the vehicle and is adapted for rotating around 
a vertical axis for the purpose of steering the vehicle and sometimes with 
use of a steering mechanism as in U.S. Pat. No. 2,427,132. The 
conventional way of braking the vehicle is by use of mechanical brakes as 
illustrated in U.S. Pat. Nos. 2,427,132 and 2,530,574. 
With the above brief description of those aspects of the concrete 
buggy-type prior art apparatus deemed pertinent to the present invention, 
it will be immediately apparent that there is a continuing need for 
improvements in the manner in which a vehicle of this type is driven as 
well as in the manner of braking the vehicle, particularly when carrying a 
heavy load. While mechanical drive systems have prevailed, it has been 
known to employ a hydraulic drive motor for driving a single rear wheel 
instead of mechanically driving two front wheels as is the conventional 
practice. In this regard, the Prime-Mover Company of Muscatine, Iowa 
52761, has made a three-wheel vehicle for handling packaged or palletized 
brick or block and sold as the L-32 and L-36 models of what is referred to 
as a "straddle-type mason tender". In the hydraulic system employed in the 
Prime-Mover apparatus both forward and reverse action as well as braking 
action are said to be achieved with a single hydraulic drive motor. 
However, except for this type of three-wheel vehicle in which a single 
rear wheel is driven by a single hydraulic drive motor, applicant is 
unaware of any other attempts that have been made to use hydraulic drive 
motors for driving three wheel concrete buggy type vehicles. 
The present invention seeks to improve upon the aforementioned prior art by 
providing in a motorized so-called "three-wheel-type dump vehicle" a 
hydraulic drive system for the front wheels, with means in the hydraulic 
system enabling the front wheels to act as brakes and also with means 
whereby the hydraulic fluid can be cooled within a reservoir which acts 
both as a structural frame member and as a uniquely-arranged heat sink in 
which the concrete or other relatively-cool material being transported in 
used to absorb heat from the hydraulic fluid. In other aspects, the 
invention also seeks to provide an improved hydraulic system enabling both 
the dump box as well as the front wheels to be hydraulically operated and 
with a minimum requirement of horsepower in the gasoline engine used as 
the prime source of power for the vehicle. Other objects will become 
apparent as the description proceeds. 
DISCLOSURE OF INVENTION 
The invention provides a three-wheel-type motorized vehicle with a tilting 
dump box pivotally mounted upon the forward end of the vehicle chassis. A 
small horsepower gasoline engine mounts on the rear end of the chassis and 
operates a two-stage hydraulic pump. The hydraulic pump forms part of a 
hydraulic system for operating the dump box and separate hydraulic drive 
motors on the front wheels. The hydraulic system also includes a reservoir 
forming a structural part of the chassis and located so as to use the 
material being transported, e.g., relatively cool concrete, for absorbing 
heat from the hydraulic fluid passing through the reservoir. The two-stage 
pump controls the volume of oil pumped as required to maintain appropriate 
hydraulic pressure as the amount of load changes, e.g., heavy loads, light 
loads, uphill and downhill transport situations. Walk behind, riding stop 
and riding seat-type variations of the invention vehicle are disclosed.

BEST MODE FOR CARRYING OUT THE INVENTION 
Making reference initially to FIGS. 1-4 and FIG. 7, the invention vehicle 
10 comprises a rectangular metal formed chassis 12 mounting a small, e.g., 
seven and one-half horsepower gasoline engine 15 at its rear end and a 
metal formed dump box load container 18 at its front end. Dump box 18 has 
a suitable pivotal mount 20 and is raised and lowered by hydraulic 
piston/cylinder 22 by means of rod 25 pivotally connected to bracket 28 on 
the bottom wall of dump box 18 and cylinder 30 pivotally connected on 
bracket 31 mounted on bar 32 (FIG. 3). 
Chassis 12 is made up of side frame members 35, 36 and end frame members 
38, 40. A metal oil reservoir tank 42 extends between and as welded to the 
metal side frame members 35, 36. Tank 42 forms a structural part of 
chassis 12. Further, the top wall 43 of tank 42 is located immediately 
below the bottom wall surface 19 of dump box 18 when in the transport 
position. Heat in tank 42 can thus be transmitted through walls 43 and 19. 
Thus, when relatively cool concrete is placed in dump box 18, such 
concrete acts as a heat sink for removing heat stored in reservoir tank 
42. Since substantial heat develops in the hydraulic system of the 
invention, particularly when the vehicle 10 is carrying relatively heavy 
loads, climbing a steep incline, or the like, an important feature of the 
invention is to provide a reservoir tank which serves the normal purpose 
of an oil reservoir as well as serving as a structural part of the vehicle 
chassis and which is located in a manner wherein the dump box itself as 
well as the material being transported can be used to absorb heat stored 
in the hydraulic fluid passing through the reservoir. 
Chassis 12 is supported in the rear by a single wheel 50 having a pivotal 
mount 52 below engine 15 enabling the operator 53 to steer by use of the 
handles 55, 56 swiveling wheel 50 on its vertical axis to change the 
direction of travel of vehicle 10. The front of chassis 12 is supported by 
two sets of dual wheels 60, 61 and 62, 63 to provide increased load 
carrying wheel surface as compared to use of single front wheels in the 
normal three-wheel type vehicle. Thus, while single front wheels could be 
substituted for the illustrated dual wheel arrangement on the front of 
chassis 12, vehicle 10 provides, in effect, a three-wheel-type vehicle 
with increased load-bearing wheel surface. 
Wheels 60, 61 are driven by hydraulic motor 65 mounted on support bar 32 
and wheels 62, 63 are driven by hydraulic motor 66, also mounted on 
support bar 32 beneath chassis 12. Thus, another important and unique 
feature of the invention is to drive the vehicle 10 by means of front 
wheels which are individually hydraulically powered by separate hydraulic 
motors, a feature in the configuration of the invention believed to be 
unique in the industry and offering numerous advantages particularly when 
transporting, reversing and braking heavy loads in industrial 
applications. 
Continuing the description in reference to FIGS. 1-4 and FIG. 7, hydraulic 
piston/cylinder 22 for raising and lowering dump box 18 is controlled by 
valve 75 through control lever 76, and drive wheel motors 65, 66 are 
controlled through valve 80 through control lever 81. As best illustrated 
in FIG. 7, it will be noted that the gasoline engine 15 drives a two-stage 
oil pump 100 with an adjustable dump such as employed in log splitters 
wherein the volume of oil pumped and the system pressure automatically 
varies as the load varies thereby enabling a relatively-small gasoline 
engine to be employed for hauling relatively-heavy loads. A Delta pump is 
one such pump in which under heavy load fluid volume is reduced and 
pressure is increased and under light load fluid volume increases and 
pressure decreases. Valves 75 and 80 are both of the type having a spring 
return to a neutral position in the case of valve 75 or stop-neutral 
position in the case of valve 80. The output of pump 100 is fed entirely 
to the control valve 75 through conduit 74 from which most of the fluid is 
continuously diverted through conduit 79 to the drive motors control valve 
80 and when desired to one side or the other of piston/cylinder 22 through 
conduits 77, 78. Valve 80 may be latched in the forward position by 
latching control lever 81 in notch 91 formed in bracket 92 (see FIG. 2). 
Conduit 43 provides a return line from valve 80 to reservoir tank 42. 
Pressurized fluid is admitted to one side or the other of the respective 
drive motors 65, 66, through conduits 83, 84 depending on whether control 
level 81 is in the forward or reverse position. Braking is achieved by 
closing the normally-open control valve 102 by utilizing a control cable 
103 and pivoted handle 104 loaded by spring 105 and mounted on handle 55. 
Thus, braking is achieved very effectively and in a simple manner using 
the drive motors 65, 66 as a front wheel braking device thus eliminating 
the need for any additional braking mechanism. 
The invention vehicle readily adapts to the riding-step-type vehicle as 
illustrated in FIG. 5 wherein there has been added a step platform 110 
secured to chassis 12 and a conventional steering mechanism 112 having a 
steering wheel 114, a steering rod 115 and steering gear box 116 suitably 
connected through chain 117 to pivot rear wheel 50. The invention also 
readily adapts to the seat-riding-type vehicle as shown in FIG. 6 wherein 
there has been added the seat 120 to the FIG. 5 construction. 
Having described the improved hydraulically driven and dump vehicle of the 
invention, it can be seen that the invention provides improvements in a 
unique reservoir forming both a structural part of the chassis as well as 
being uniquely located to dissipate the substantial amount of heat that is 
inevitably developed in a hydraulic system under heavy load. Further, the 
invention can also be seen to provide an extremely simple hydraulic front 
wheel drive mechanism for achieving both forward and reverse directions of 
travel as well as a quick and effective means for braking, either under 
normal or emergency conditions. Additionally, by use of the two-stage oil 
pump, the invention also achieves the advantage of being able to use a 
relatively small horsepower engine for transporting relatively heavy loads 
.