JP2897048B2 - Front and rear wheel drive motorcycle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in front-rear-wheel drive motorcycles.

(Conventional technology) Motorcycles include a type in which only the rear wheels are driven by the engine and a type in which the front wheels are also driven by the engine, that is,
There is a front and rear wheel drive motorcycle. Although not shown, the front and rear wheel drive motorcycle has an advantage that the front and rear wheels are respectively driven, so that the motorcycle can travel smoothly on a slippery road surface without slipping. On the other hand, since the front wheels are steered by the front forks, there is a disadvantage that a rotation difference is generated between the front wheels and the rear wheels, and the structure becomes complicated.

As prior art documents of this kind, for example,
No.-6923 and JP-A-60-18478.

(Problems to be Solved by the Invention) The conventional front-wheel drive motorcycle has a problem in that the left and right weight balance of the vehicle body is lost because the chains driving the front wheels and the rear wheels are concentrated on one side of the frame. Further, since the driving portion of the front wheels becomes heavy, the load distribution of the front wheels becomes large, and there is a disadvantage that the handling becomes heavy. Further, it is necessary to attach a one-way clutch such as an overrun clutch on the drive side of the front wheel so that the front wheel can overrun during steering and the rotation difference between the front and rear wheels does not become a brake.

The present invention has been made in view of the above, to improve the right and left weight balance of the vehicle body, to improve the handling by appropriately distributing the load of the front wheels, to provide a rotation difference absorbing and torque distribution device on the drive side of the front wheels. The aim is to obtain a front-rear wheel drive motorcycle that can be expected to run smoothly.

(Means for Solving the Problems) In the present invention, in order to achieve the above object, a front fork is supported at the front of a frame of a motorcycle so as to be steerable, and is rotatably supported at a lower end of the front fork. And a rear wheel rotatably supported on a rear portion of the frame, driven by an engine mounted on a lower front portion of the frame between the front and rear wheels, wherein the front and rear portions are disposed between the front fork and a front upper portion of the engine. A rotation difference absorbing and torque distributing device for wheels is disposed with its rotation axis directed in the left-right direction of the vehicle body, and the output shaft of the engine, the rotational difference absorbing and torque distributing device, the output shaft of the engine, and the rear wheel are Are connected by a front chain and a rear wheel chain on one side in the left-right direction of the vehicle body. A constant velocity joint mounted in parallel with the torque distributing device and the rotational difference absorbing and torque distributing device are connected by a connecting chain on the other side in the left-right direction of the vehicle body opposite to the front chain. A drive shaft is arranged on one side in the left-right direction of the vehicle body on the same side as the front chain and the rear wheel chain, and a driving force is transmitted from the constant velocity joint to the front wheels.

Preferably, a radiator for cooling the cooling water of the engine is disposed on a front portion of the vehicle body opposite to the front chain and the rear wheel chain disposed on one side in the left-right direction of the vehicle body, and on a frame front portion on the other side in the left-right direction of the vehicle body. .

Further, a front end of a muffler is connected to the engine, a front portion of the muffler is disposed across the left and right sides of the vehicle body, and a rear chain and a rear wheel are provided with a rear portion of the muffler disposed on one side in the left-right direction of the vehicle body. It is desirable to arrange on the other side in the left-right direction of the vehicle body opposite to the chain, and to extend rearward of the vehicle body.

(Operation) According to the present invention, when the engine is driven, the driving force is transmitted from the engine to the rear wheels via the rear wheel chain. Further, the driving force is transmitted from the engine to the front wheels via the front chain, the rotation difference absorbing and torque distribution device, the connecting chain, the constant velocity joint, and the drive shaft in order. By transmitting such driving force, the front and rear wheel drive motorcycle is
The front and rear wheels respectively drive and travel. At this time, if a rotation difference occurs between the front wheel and the rear wheel due to the steering of the front fork, the rotation difference absorbing / torque distribution device slips and the front wheel overruns. Further, since the rear wheel chain, the front chain, and the drive shaft are located on one side in the left-right direction of the vehicle body and the connecting chain is located on the other side in the left-right direction of the vehicle body, the right and left weight balance of the vehicle body is improved. Further, since the rotation difference absorbing and torque distributing device can be mounted in a gap between the front fork and the front fork, the space is not occupied significantly. In addition, the drive shaft for driving the front wheels can be configured to be lightweight below the constant velocity joint, and can have a proper load distribution on the front wheels and can be easily handled.

According to the second aspect of the present invention, since the radiator is located on the other side in the left-right direction of the vehicle body, the connection chain and the radiator cooperate to achieve a good left-right weight balance of the vehicle body.

Further, according to the third aspect of the present invention, since the muffler is located on the other side in the left-right direction of the vehicle body, the connection chain, the radiator, and the muffler cooperate to further improve the right and left weight balance of the vehicle body.

(Embodiment) Hereinafter, an embodiment of a front and rear wheel drive motorcycle according to the present invention will be described with reference to the drawings.

The front-rear wheel drive motorcycle according to the present embodiment includes a front fork 13 that can be steered to the front portion (left side in FIGS. 1 and 2) of the frame 2 of the motorcycle as shown in FIGS. The front wheel 10 is supported at the lower portion of the front fork 13 to support the front wheel 10. The engine 1 is mounted on the frame 2, and the rear wheel 4 is mounted on the rear portion of the frame 2 (the right side in FIGS. 1 and 2). And the engine 1 drives the front wheel 10 and the rear wheel 4 respectively.

The engine 1 has a built-in clutch (not shown) for connecting and disconnecting operation and a multi-stage gear reducer (not shown), and is mounted below the front part of the frame 2. In the engine 1, the end of the output shaft 3 is directed leftward in the left-right direction of the vehicle body (see the lower side in FIG. 1), and the output shaft 3 and the rear wheel 4 pass leftward in the width direction of the rear wheel 4. The chain is connected by an endless rear wheel chain 5, and the rear wheel 4 is driven to rotate by the circulation of the rear wheel chain 5. Further, the output shaft 3 is an endless front chain which passes diagonally forward of the engine 1, in other words, a rotation shaft of a rotation difference absorbing and torque distribution device 6 attached to a front portion of the frame 2 and which passes through the left side in the left-right direction of the vehicle body. 7 are connected.

As shown in FIG. 3, the rotation difference absorbing and torque distributing device 6 rotates the cam groove 12 with the pin 11 and presses the pressure plate 9 of the multi-plate clutch 8 with the reaction torque of the front wheel 10. When the reaction torque is small, the transmission torque is small, and when the front wheel 10 overruns due to steering, the multi-plate clutch 8 slips to absorb the rotation difference.

4 and 5, a constant velocity joint 15 extending in the left-right direction of the vehicle body is supported directly below the steering shaft 14 of the front fork 13 for ensuring steering. The constant velocity joint 15 is connected to the rotating shaft of the rotation difference absorbing and torque distributing device 6 by two endless connecting chains 16 on the right side in the left-right direction of the vehicle body (see the upper side in FIG. 1). On the front left side of the front fork 13,
A rotatable drive shaft 17 located below the constant velocity joint 15 is rotatably supported. The drive shaft 17 is configured such that a driven 18 at a lower portion thereof slides together with a telescopic cushion of the front fork 13 to rotate integrally with the drive shaft 17.

The constant velocity joint 15 is connected to the drive shaft 17 by a pair of gears 19, a bevel pinion 20, and a bevel gear 21 on the left and right sides of the vehicle body, and the driven 18 is connected to the lower front wheel 10 by a bevel pinion 22 and a bevel gear 23. Have been. With such a configuration, in the front-rear-wheel drive motorcycle, the front wheels 10 are driven and rotated by driving the engine 1.

24 is a radiator for cooling the cooling water of the engine 1,
The radiator 24 is installed on the front part 2 of the frame 2 on the right side in the left-right direction of the vehicle body (see FIG. 1).

Reference numeral 25 denotes a muffler for the engine 1.
The front end 25a is connected to the lower part of the engine 1 and the front part 25b is in the left-right direction of the vehicle body (vertical direction in FIG. 1).
The front chain 7 and the rear wheel chain 5 have a rear portion 25c disposed on the left side in the left-right direction of the vehicle body.
The vehicle body is supported and disposed on the right side in the left-right direction of the vehicle body on the opposite side, in other words, on the other side in the left-right direction of the vehicle body, and extends obliquely toward the rear portion of the frame 2 (rightward in FIG. 1). .

According to the above configuration, the rear wheel chain 5, the front chain 7, the drive shaft 17, the driven
18, a gear 19, a bevel pinion 20, a bevel gear 21, a bevel pinion 22, and a bevel gear 23, and a connecting chain 16, a radiator 24, and a muffler 25 are arranged on the right side in the left-right direction of the opposite vehicle body. The balance between the left and right weights can be made very good. Also,
The rotation difference absorbing / torque distributing device 6 is mounted between the front fork 13 and the front portion of the frame 2 to make effective use of space, and the front wheels 10 can be overrun during steering. In addition, the drive shaft 17 can be made shorter and lighter below the constant velocity joint 15 of the front fork 13, thereby making it possible to optimize the load distribution of the front wheel 10 and significantly improve handling. Become. Furthermore, the left and right width of the vehicle body is narrowed as a whole, so that downsizing and weight reduction can be greatly expected.

(Effects of the Invention) As described above, according to the present invention, there is an effect that the right and left weight balance of the vehicle body can be improved, and the distributed load of the front wheels can be made appropriate to improve the handling. Further, since the rotation difference absorbing and torque distribution device is provided on the drive side of the front wheels, smooth running can be expected.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a front and rear wheel drive motorcycle according to the present invention. FIG. 1 is an overall plan view, FIG. 2 is a side view thereof, FIG. FIG. 4 is a vertical sectional front view of a main part of a front fork portion, and FIG. 5 is a side view of the same. 1 ... engine, 2 ... frame, 3 ... output shaft, 4 ... rear wheel,
5 rear wheel chain, 6 rotation difference absorption and torque distribution device,
7 ... front chain, 10 ... front wheel, 13 ... front fork,
15 ... constant velocity joint, 16 ... connecting chain, 17 ... drive shaft, 18 ... driven, 19 ... gear, 20 ... bevel pinion, 21 ... bevel gear, 22 ... bevel pinion, 23 ... bevel gear, 24 ... radiator, 25 ... muffler.

Claims (3)

(57) [Claims] A front fork is supported at a front portion of a frame of a motorcycle so as to be steerable, and a front wheel rotatably supported at a lower end of the front fork and a rear wheel rotatably supported at a rear portion of the frame. In a front-rear wheel drive motorcycle driven by an engine mounted on a front lower portion of a frame between the front and rear wheels, a rotation difference absorbing / torque distribution device for the front and rear wheels is provided between the front fork and the front upper fork of the engine. The rotating shaft is arranged in the left-right direction of the vehicle body, and the output shaft of the engine, the rotation difference absorbing and torque distributing device, and the output shaft of the engine and the rear wheel are respectively connected to the front chain and the rear wheel chain of the vehicle body. A constant-velocity motor connected to one side in the left-right direction while a rotating shaft is attached to a vehicle body directly below a steering shaft of the front fork in parallel with the rotation difference absorbing and torque distributing device. The front fork and the front chain and the rear wheel chain are connected to the front fork while connecting the int and the rotation difference absorbing and torque distributing device with a connecting chain on the other side in the left-right direction of the vehicle body opposite to the front chain. A front and rear wheel drive motorcycle, wherein a drive shaft is disposed on one side in the left-right direction of the vehicle body, and a driving force is transmitted from the constant velocity joint to the front wheels. 2. A radiator for cooling the cooling water of the engine is disposed at a front portion of the vehicle body opposite to the front chain and the rear wheel chain at one side in the left-right direction of the vehicle body, and at a front portion of a frame on the other side in the left-right direction of the vehicle body. A front-rear wheel drive motorcycle according to claim 1. 3. A front chain in which a front end of a muffler is connected to the engine, a front portion of the muffler is disposed on the left and right sides of the vehicle body, and a rear portion of the muffler is disposed on one side in the left-right direction of the vehicle body. The front-wheel drive motorcycle according to claim 1 or 2, wherein the motorcycle is disposed on the other side in the left-right direction of the vehicle body opposite to the rear wheel chain and extends rearward of the vehicle body.