GB2091653A

GB2091653A - An all-terrain or off-road vehicle with two individual gear transmissions

Info

Publication number: GB2091653A
Application number: GB8102560A
Authority: GB
Original assignee: PI HSIANG WU
Current assignee: PI HSIANG WU
Priority date: 1981-01-28
Filing date: 1981-01-28
Publication date: 1982-08-04

Abstract

An all-terrain or off-road vehicle has two individually controlled gear transmissions 1, 2 through which the driving force is transmitted from the engine 3 to the left and right wheels. Left and right steering levers 21, 22 control tensioning of respective drive belts 11, 12 and operation of brake chambers 23, 24. Separate gear levers 13, 14 independently control selection of forward and reverse drive in the transmissions 1, 2 so that the vehicle may be turned on the spot. <IMAGE>

Description

SPECIFICATION An all-terrain or off-road vehicle with two individual gear transmissions The present invention relates to an all-terrain or off-road vehicle having two individual gear transmissions which allow vehicle to make a turn in all directions on the spot (same turning center).

Conventional off-road vehicles or crawlers are mostly driven by a single gear box usinga directional clutch engaged or disengaged inside the gear box for driving forward or backward, or making a turn. However, in this type of vehicle, quite a large space is required for the vehicle to make a turn.

By installing two sets of hydraulic pumps and motors, the vehicle can make a turn in all directions on the spot. But these pumps and motors are expensive, and require a great deal of maintenances and higher horsepower engines for operation.

Briefly, the present invention overcomes the disadvantages of the prior off-road vehicle by providing a double-steering transmission which allows vehicles to make a turn in ail directions on the spot.

Accordingly, it is a primary object of the present invention to provide an all-terrain or off-road vehicle with two individual gear transmissions which comprise of the left and right steering levers which control the clutches and brakes of the vehicle in order to allow vehicle to make a turn in all directions on the spot.

Other objects of the present invention will become apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS: Figure 1 is a perspective view of an embodiment of a vehicle in accordance with the present invention.

Figure 2 is a top view of the vehicle of Figure 1, in which certain parts being omitted or shown in phantom line for clarity.

Figure 3 is a side view of the vehicle of Figure 1.

Figure 4 shows a schematic view of one of the steering levers connected to the clutch and brake of a transmission.

DETAILED DESCRIPTION OF THE INVENTION: Referring to Fig 1-4, all-terrain or off-road vehicle according to the present invention comprises a drive control means for a vehicle which is having a frame, right wheels and left wheels, a power drive unit connected through a drive chain to the wheels comprising, two independent drive means operatively connected to the drive shaft of the power unit, two individual gear transmissions each separately and operatively connected to one of the said independent drive means to be driven thereby, separate right and left drive axles, each of the said transmissions being separately and operatively connected to one of the said drive axles, right and left wheel drive means operatively connected to the said right and left wheel drive means operatively connected to the said right and left drive axles respectively to drive said wheels, and separate control means to independently control the operation of said right and left wheel drive means so that with the said control means, the vehicle may be driven forward, backward, or turned on the spot. Each gear transmission includes gear box having a gear reduction mechanism for forward and backward operation.

When using the synchronized-changing gear the vehicle can travel forward or backward or make a turn to the left or to the right. Instead of using synchronized changing gear by individually shifting one of the gear transmissions to a reverse position and the one to a forward position, the vehicle can make a turn on the spot (same turning center). This is the most important feature of the present invention. With the two individual gear transmissions, the vehicle can carry a much heavier load than that of the one using a single gear box.

Vehicles using two individual gear boxes are manufactured very easily and its cost is rather low comparatively without sacrificing the features of the hydraulic type, which is another feature of this invention. The vehicle assembly and its driving device are shown in detail in Fig. 2, and Fig. 3. The driving power from the engine 3 is transmitted to the two individual transmissions 1 8 2 thru the right and left steering clutches 9 t 10 and thru the belts 11 & 1 2 respectively. The two transmissions 1 8 2 are resepectively controlled by the right and left gear levers 1 3 & 14.The driving force is transmitted thru the two main drive shafts 1 5 a 1 6 to the chain sprockets 1 7a, 1 7b, 1 8a, Et 1 8b, and then transmitted to the front and rear wheels thru the driving chains 1 9a, 1 9b, 20a, 8 20b respectively so as to accomplish the all-terrain multi-wheel off-road driving system.

When the gear levers 13 and 14 of the two respective transmissions are operated in synchronization, the right and left steering levers 21 8 22 will control the clutch and brake of the transmissions 1 8 2 respectively so as to drive the vehicle forwards, backwards, or to allow the vehicle to make a turn at various angles. When the operations of the gear levers 13 8 14 are not in synchronization i.e. one is in forward gear position and the other in reverse gear position, (but the speed ratio of the gears is the same) the vehicle would turn around on the spot without going forward or backward.

Figure 4 shows the steering lever controlling the idler-wheel clutch and brake directly: no further details of this mechanism are shown, since the construction and manner of operation of such devices are common knowledge to persons who are familiar with the automotive and related arts.

Since the control systems of the right and left steering levers 21 and 22 are the same, the following only explains the operation of the right steering lever 21, separate idler-wheel clutch 9 and the brake chamber 23. When the steering lever 21 is pulled in the direction of the driver's seat, the steel wire 25, the outer sheath of which is fixedly mounted on the frame, will release the idler-wheel 28 from the belts 11 and thus cause the transmission 1 to lose its driving force.

When the steering lever 21 is pulled backwards gradually to different positions, differential speeds between the right and left transmissions 1 and 2 are produced through the variable slipping of belt drive 1 Thus the steering angle depends upon the pulling angle of the steering lever 21.

When the left and right steering levers 22 8 21 are pulled simultaneously to the end position, the .vehicle will stop without pushing down the main foot peddle clutch. In the forwardmost position of the left and right steering levers 22 S 21, the vehicle will move straightforward. Consequently, the moving and turning of the vehicle may be controlled by the left and right steering levers 22 821.

Claims

1. A drive control means for a vehicle which is having a frame, right wheels and left wheels, a power drive unit connected through a drive chain to the wheels comprising, two independent drive means operatively connected to the drive shaft of the power unit, two individual gear transmissions each separately and operatively connected to one of the said independent drive means to be driven thereby, separate right and left drive axles, each of the said transmissions being separately and operatively connected to one of the said drive axles, right and left wheel drive means operatively connected to the said right and left wheel drive means operatively connected to the said right and left drive axles respectively to drive said wheels, and separate control means to independently control the operation of said right and left wheel drive means so that with the said control means, the vehicle may be driven forward, backward, or turned on the spot.

2. The drive control means as claimed in Claim 1, wherein each of the said independent drive means comprises a belt drive mechanism which is having an idler-tensioning clutch controlled by one of the said control means to vary the drive ratio between the input and the output of said belt drive.

3. The drive control means as claimed in Claim 3, wherein the said idler-tensioning clutch comprises an idler wheel rotatably mounted on a support bracket, said support bracket being pivotably mounted on the frame so that the idler wheel can be manipulated to engage and disengage the belts of said belt drive mechanism and to vary the tension of said belts to vary said drive ratio.

4. The drive control means as claimed in Claim 4, wherein each of the said control means comprises a steering lever mounted on the frame and operatively connected to said idler support bracket to control the tension on the said belts.

5. The drive control means as claimed in Claim 5, further comprises two separate gear levers each being operatively and independently connected to one of the said gear transmissions to control the operation thereof.

6. A drive control means substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.

7. A vehicle substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.