GB2119329A

GB2119329A - Multiple drive mechanism for an agricultural vehicle

Info

Publication number: GB2119329A
Application number: GB08212216A
Authority: GB
Inventors: Wu Cheng-Hsun
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-04-27
Filing date: 1982-04-27
Publication date: 1983-11-16
Also published as: GB2119329B

Abstract

A multiple drive mechanism for an agricultural vehicle comprises two individual change-speed transmissions 7, 8 driven by a single engine 9, one of the transmissions is secured and connected to a differential 79 disposed between two front drive half shafts 2 each provided with a drive wheel 5, 5' while the other transmission 8 is secured and connected to a continuous rear drive shaft 4 provided with a pair of drive wheels 6, 6'. A pair of differential axle sleeves 84, 84' are disposed between the ends of the continuous rear drive shaft and the rear drive wheels. One of the transmissions 7, 8 can be put in neutral to allow two-wheel drive via the other of transmissions 7, 8. The vehicle comprises front and rear frames articulated together about a longitudinal horizontal axis. <IMAGE>

Description

SPECIFICATION Multiple drive mechanism for an agricultural vehicle The present invention relates to a vehicle such as an agricultural vehicle having two individual transmission gearings for driving all of the wheels or only two of the wheels of the vehicle.

Conventional agricultural vehicles such as power carts, crawlers etc. are mostly driven via a single gear box using a directional clutch engaged or disengaged inside the gear box, as well as a single drive shaft. Such a drive shaft will be easily bent or broken when in operation, due to the fact that there is no spring provided for transforming short sharp jolts resulting from poor road surfaces into damped oscillations, and quite a large force is transmitted to the drive shaft. Furthermore, in such power carts, a single frame is supported by the front and rear shafts which are provided with the wheels, hence slipping of the wheels on the ground will easily occur if one of the wheels is stuck in a hole in soft ground.

An object of the present invention is to provide a multiple drive mechanism for an agricultural vehicle in which two sets of individual transmissions and drive shafts are used in order to increase the ground gripping force, drive force and loading capacity.

According to the present invention there is provided a multiple drive mechanism for an agricultural vehicle comprising front and rear individual transmissions arranged to be driven by the same power source, one of the front and rear transmissions being secured and connected to a differential disposed between two half shafts each provided with a drive wheel while the other transmission is secured and connected to a continuous drive shaft provided with a pair of drive wheels; a pair of differential axle sleeves disposed between the end of the continuous drive shaft and the drive wheels; and front and rear frames secured on the front and rear drive shafts, respectively.

A multiple drive mechanism for an agricultural vehicle may be provided with two frames which are respectively secured on the front and rear drive shafts, and connected one with the other by means of a rotatable shaft longitudinally arranged therebetween in order that the front shaft may be angularly moved relative to the rear shaft so as to keep the front and rear wheels in contact with the ground during movement of the vehicle in order to prevent the wheels from slipping on the ground.

The multiple drive mechanism has a differential which is used with the front drive shaft. Two sets of differential axle sleeves are disposed between the end of the continuous rear drive shaft and the rear drive wheels in order to let the wheels run at different speeds while still driving the vehicle, and to allow the vehicle to make a turn.

An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which: Figure lisa top view of an embodiment of a multiple drive mechanism for an agricultural vehicle in accordance with the present invention; Figure 2 is a side view of the drive mechanism of the agricultural vehicle of Figure 1; and Figure 3 is a view showing the power transmission of the drive mechanism of Figures 1 and 2.

Referring now to Figures 1 to 3, there is shown a multiple drive mechanism for a n an agricultural vehicle comprising a front frame 1 securely coupled with front drive shaft 2 and a rear frame 3 securely coupled with rear drive shaft 4. A pair of front wheels (5,5') are secured on the ends of the front shaft 2 while a pair of rear wheels (6, 6') are secured on the ends of the rear shaft 4. A front transmission 7 is disposed at an intermediate portion of the front shaft 2, and a rear transmission 8 is disposed on the intermediate portion of the rear shaft 4.An engine 9 is mounted on the front frame 1, and a shaft 10 is rotatably longitudinally secured on an intermediate portion of the end of the front frame 1 by means of two bearings (11, 11'), and connected with the bottom of the front of the rear frame 3 in order that the front frame, secured on the front drive shaft provided with front wheels, may be angularly moved relative to the rear frame, secured on the rear drive shaft provided with rear wheels, so as to keep the front and rear wheels in contact with the ground during movement of the vehicle in order to prevent the wheels from slipping on the ground, and to increase travel stability.

Referring now to Figure 3, an engine 9 includes a transverse output shaft 91, a belt 92 which is disposed around a pulley 93 mounted on the end of the output shaft 91, and a pully 94 mounted on one end 711 of a horizontal input shaft 71 of the front transmission 7. The other end 712 of the input shaft 71 extends through the front transmission 7 and is connected to one end of an intermediate drive shaft 72 by means of bevel gears 73 and a universal joint 74. The opposite end 721 of the intermediate drive shaft 72 is also connected to one end of an input shaft 81 of the rear transmission 8 by means of bevel gears 75 and a universal joint 76.

The drive power can be transmitted from the engine 9 to input shafts 71 and 81 of the gear transmissions 7 and 8 by means of an idle-wheel clutch 95. The idle-wheel clutch 95 is mounted on a bracket 96 secured on the front frame 1, and connected to a foot pedal 97 through a steei wire 98 in order that the idle-wheel clutch 95 can be operated by the foot pedal to engage or disengage the belt 92.

The idle-wheel clutch is shown in the disengaged position in which no power can be transmitted to the input shafts 71 and 81.

The front and rear transmissions 7 and 8 can be conventional transmissions, and can be identical in construction. They are respectively controlled by front and rear gear levers 77 and 82, and comprise an output shaft 78 (83). The output shaft 78 of the front transmission 7 serves as a front drive shaft which is divided into two halves which are con nected one with the other through a conventional differential 79. With this conventional differential, the front wheels can run at different speeds while still driving the carrier, in order to allow the carrier to make a turn.

The output shaft 83 of the rear transmission 8 is a continuous shaft which acts as the rear drive shaft. A set of conventional differential sleeves (84,84') are arranged between ends 831 and 832 of the rear drive shaft 83 and rear wheels (6, 6'), respectively, in order to let the rear wheels run at different speeds while still driving the carrier, so as to allow the carrier to make a turn.

It should be noted that the front and rear trasmissions 7 and 8 should be operated in the same speed position e.g. high speed, low speed or neutral by means of the front and rear gear levers 77 and 82 in order that the front and rear wheels drive the cart at the same speed, and form a multi drive vehicle.

However, if one of the front and rear transmissions 7 and 8 is in the neutral position, the other transmission may be in any one of the speed positions or in the neutral position.

A rear brake 85 is provided on the rear transmission 8, and is connected to a foot pedal 86 through a steel wire 87 in order that the rear brake may be actuated by the foot pedal 86.

Therefore, there is disclosed a multiple drive mechanism for an agricultural vehicle comprising front and rear individual transmissions arranged to be driven by the same power source, one of the front and rear transmissions being secured and connected to a differential disposed between two half shafts each provided with a drive wheel while the other transmission is secured and connected to a continuous drive shaft provided with a pair of drive wheels; a pair of differential axle sleeves disposed between the end of the continuous drive shaft and the drive wheels; and a frame supported by the front and rear drive shafts.

Claims

1. A multiple drive mechanism for an agricultural vehicle comprising front and rear individual transmissions arranged to be driven by the same power source, one of the front and rear transmissions being secured and connected to a differential disposed between two half shafts each provided with a drive wheel while the other transmission is secured and connected to a continuous drive shaft provided with a pair of drive wheels; a pair of differential axle sleeves disposed between the end of the continuous drive shaft and the drive wheels; and front and rear frames secured on the front and rear drive shafts, respectively.

2. A mechanism as claimed in Claim 1, including a rotatable shaft longitudinaliy arranged between the front and rear frames to allow relative rotational movement therebetween.

3. A mechanism as claimed in Claim 2, wherein the rotatable shaft is mounted in bearings on the rear of the front frame and attached to the bottom of the front of the rear frame.

4. A mechanism as claimed in Claim 1 or 2, wherein the front transmission is secured and connected to the differential disposed between the two half shafts which are each provided with a front drive wheel.

5. A mechanism as claimed in Claim 3, wherein the rear transmission is secured and connected to the continuous drive shaft each end of which is connected with a rear drive wheel.

6. A multiple drive mechanism substantially as hereinbefore described with reference to, and as illustrated in, the accompany drawings.