JPH0674005B2 - Vehicles for running on rough ground - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention has a rear arm rotatably mounted vertically near a rear portion of an engine mounted near the center of a vehicle body. The present invention relates to a small waste vehicle for holding a rear wheel and having a towing device for towing a trailer at a rear portion of a vehicle body.

(Background of the Invention) A three-wheeled or four-wheeled saddle-ride type vehicle for traveling on rough terrain equipped with wide ultra-low pressure tires, in which a rear fender is covered with a rear fender, and a straddle-type vehicle is mounted on the upper surface of the rear fender. It is known that a driving seat is attached. Also in this case,
The front end of the rear arm is pivotally attached to the frame near the rear of the engine mounted near the center of the vehicle body, the rear wheel axle is held at the rear end of this rear arm, and the rear arm is supported by the cushion unit, so that the rear wheel is of the rear arm type. Some of them are held by a rear wheel suspension so that they can be moved up and down. When a trailer towing device is provided in this type of vehicle, it is desirable that the trailer's towing load does not cause a change in vehicle posture. Further, since the rear fender and the driving seat extend rearward above the rear wheels, when the trailer towing device is arranged below these, the rear fender and the seat are likely to hinder the work of attaching and detaching the trailer. The problem arises.

(Object of the Invention) The present invention has been made in view of such circumstances, and when a pair of left and right rear wheels is held by a vertically swingable rear arm and a trailer traction device is provided between the rear wheels, a trailer is provided. It is an object of the present invention to provide a saddle riding type vehicle for running on rough terrain in which the towing load of the vehicle is less likely to affect the driving posture of the vehicle and the workability of attaching and detaching the trailer is good.

(Construction of the Invention) According to the present invention, an object is to provide an engine mounted near the center of a vehicle body, and a frame near the rear portion of the engine in which a front end is pivotally attached by a pivot shaft to a rear cylinder in the vehicle width direction at the rear end. A vertically swingable rear arm, a cushion unit hung between the frame and the rear arm, and a gear case that is arranged in parallel with the rear cylinder at the rear end of the rear arm in the vehicle width direction to accommodate a final reduction gear. A rear axle that penetrates the gear case and the rear cylinder and has rear wheels attached to both ends thereof; and a drive shaft that is inserted into the rear arm and transmits the output of the engine to the rear axle via the final reduction gear. A rear-mounted vehicle having a long, front-and-back straddle-type driving seat in the upper part of the vehicle body and having a space that opens rearward between the rear arm and the driving seat. Is tilted so that the rear part thereof is lower than the pivot shaft in the non-riding state, the gear case is arranged offset in the width direction of the vehicle body, and the pivot is attached to the rear cylinder near the center of the vehicle width direction. This is accomplished by a vehicle for traveling on rough terrain, characterized in that a bracket extending in the direction of extension of a straight line from the shaft to the rear axle is fixed, and the bracket is provided with a connecting device for trailer towing.

(Embodiment) FIG. 1 is a side view showing an embodiment of the present invention with a left rear wheel removed, FIG. 2 is a plan view of an essential part thereof, and FIG. 3 is III- in FIG. It is a III line sectional view. 1 and 2, reference numeral 10 is a frame, which includes a steering shaft tube 12, a main tube 14, and a pair of left and right seat pillar tubes 16 (16
a, 16b), down tube 18 (18a, 18b), back tube 20 (20a, 20b), seat rail 22 (22a, 22b), and the like. Seat pillar tube 16 and back tube
The lower end of 20 and the rear end of the down tube 18 are
It is fixed to a, 24b). A steering shaft (not shown) is rotatably held by the steering shaft cylinder 12, and upper and lower brackets 26, 28 are fixed to the vertically protruding ends of the steering shaft. The front fork 30 is fixed to the. A front wheel 32 is attached to the lower end of the front fork 30. The front wheel 32 has a wide ultra-low pressure tire. 34 is seat pillar tube 16 and down tube 18
Between the front wheel 32 and the rear wheel 50 described later.

A rear arm 36 has a front cylinder 38, a rear cylinder 40, and a left cylinder 42 and a right cylinder 44 connecting the both cylinders 38, 40. The front cylinder 38 has a pivot shaft 46 (Fig. 3) between the bearing cylinders 24a and 24b.
As a result, the rear arm 36 is tilted so that its rear part is lower than the pivot shaft 46 in the non-riding state, and can swing up and down about the pivot shaft 46. A rear axle 48 is rotatably held by the rear cylinder 40.
A pair of rear wheels 50 (50a, 50b) are fixed to the left and right protruding ends of the. A wide ultra-low pressure tire is mounted on the rear wheel 50. Reference numeral 52 denotes a cushion unit, the front end of which is pivotally attached to a bracket 54 fixed to the lower surface of the rear portion of the main tube 14. Brackets 56 and 58 projecting obliquely upward and upward are fixed to the rear cylinder 40 of the rear arm 36, and the rear end of the cushion unit 52 is pivotally attached to the bracket 58.

A liquid-tight gear case 60 is formed at the joint between the rear cylinder 40 and the left cylinder 42 of the rear arm 36. The gear case 60 accommodates a large gear 62a and a small gear 62b that form the final reduction gear 62, and these gears 62 are immersed in the gear oil contained in the case 60. Gear wheel 62a is the case 6
It is fixed to the rear axle 48 passing through 0. Also small gear 62b
Is connected to a drive shaft 64 (FIG. 1) inserted in the left cylinder 42. The front end of the drive shaft 64 is connected to the engine through a universal joint (not shown) located between the bearing tubes 24a and 24b.
It is connected to 34 output shafts (not shown). Therefore, the rotation of the output shaft of the engine 34 is controlled by the universal joint, the drive shaft 64, and the small gear.
It is transmitted to the rear wheel 50 via 62b, the large gear 62a, and the rear axle 48.

A breather pipe 66 forming an air passage is connected to an upper portion of the gear case 60 so as to communicate with the inside of the case 60. The breather tube 66 extends upward along the main tube 14 via the left cylinder 42 of the rear arm 36 and the left seat pillar tube 16a. As a result, the opening 66a on the atmosphere side of the breather pipe 66 comes to a position higher than the line A (FIG. 1) connecting the upper ends of the front wheels 32 and the rear wheels 50. This opening
66a points downward so as to deviate from the traveling direction of the vehicle,
It prevents rainwater from entering the opening 66a while driving in the rain. In FIG. 1, 68 is a fuel tank mounted so as to straddle the opening 66a, 70 is a rear fender that covers the left and right rear wheels 50, and 72 is a vertically long operation seat. This driving seat
A space that opens rearward is formed between 72 and the rear arm 36.

As shown in FIG. 3, a tongue-shaped bracket 74 that extends rearward from the vicinity of the center in the vehicle width direction is fixed to the rear cylinder 40, and the above-described bracket 56 that extends forward and upward and the bracket 74.
And another bracket 76 (76
a, 76b) are bolted. The bracket 76 extends rearward from the tongue-shaped bracket 74, and a spherical protrusion 78 protruding upward is fixed to the end portion thereof. This protrusion
The tow rod 82 of the trailer 80 shown in FIG. 1 is connected to 78. That is, as shown in FIG. 3, a hemispherical shell-shaped engagement arm 84 having an opening at the bottom is fixed to the front end of the tow rod 82, and the engagement arm 84 is covered by the projection 78 to connect the two. . The solid line in FIG. 3 shows the vehicle when the vehicle is not in a ride state. In this state, the tongue-shaped bracket 74 and the rear portion of the bracket 76 are directed obliquely downward and rearward. The phantom line in the figure indicates the time when the driver gets on the vehicle. At this time, the pivot shaft 46 sinks downward together with the frame 10, and the tongue-shaped bracket 74 and bracket 76
The rear part is in a substantially horizontal position. Therefore, when the driver rides on the trailer 80 and pulls the trailer 80, the trailer pulling force acts horizontally on the brackets 74 and 76 in the substantially horizontal position, and the bending moment applied to the brackets 74 and 76 is minimized. As a result, the influence of the trailer towing load on the driving posture of the vehicle can be reduced.

The bracket 76 is attached to the rear cylinder 40 at the rear of the rear arm 36.
The gear case 60 is mounted so as to be located near the center in the vehicle width direction above, and the gear case 60 is displaced to the left of the center in the vehicle width direction (see FIG. 2). Without the bracket 76 short enough, the rear arm
Connect the connection between the rear end of the 76 and the tow rod 82 of the trailer 80 to the rear axle 48.
Can be approached. As a result, the vertical movement amount of the connecting portion due to the swinging of the rear arm 76 becomes small, and conversely, the load fluctuation of the trailer 80 applied to the connecting portion reduces the action of swinging the rear arm 76 up and down. Ie rear arm
The influence of the vertical force exerted between the 76 and the trailer 80 is weakened.

According to this embodiment, the inside of the gear case 60 is a breather tube.
Since the 66 communicates with the atmosphere, if the temperature inside the case 60 rises when the vehicle is running, part of the air inside the case 60 escapes from the opening 66a of the breather pipe 66 to the atmosphere, and when the vehicle is stopped. If the temperature inside the case 60 decreases while being left as it is, air will enter the case 60 through the opening 66a and the breather pipe 66. For this reason, the inside of the case 60 is always maintained at almost atmospheric pressure, an excessive air pressure does not act on the seal portion of the case 60, and the seal portion is not damaged. Further, since the opening 66a of the breather pipe 66 is located at a high position, water does not flow into the case 60 through this opening 66a. This type of vehicle sometimes uses the buoyancy of tires to float on the surface of water and cross rivers and swamps, but since the tires are wide and thick, sufficient buoyancy is generated. Therefore, the vehicle body is not submerged so much that the front and rear wheels 32 and 50 are completely submerged. Since the opening 66a of the breather pipe 66 is located above the line A connecting the upper ends of the front and rear wheels 32, 50, even when the entire vehicle is floated on the water surface and crossed over the water,
The opening 66a is never submerged in water. Therefore, even at this time, water does not flow into the case 60, and there is no possibility that the deterioration of the gear oil or the life of the final reduction gear 62 is adversely affected.

Although this embodiment applies the present invention to a three-wheeled vehicle, it goes without saying that the present invention also includes one applied to a four-wheeled vehicle.
In addition, the breather pipe 66 as the air passage is 1 in this embodiment.
Although it is formed of a book tube, a plurality of tubes may be connected, or the seat pillar tube 16, the back tube 20 and the like that form the frame 10 may be used as a part of this air passage.

(Effect of the invention) As described above, according to the present invention, the rear arm is tilted so that its rear part is lower than the pivot shaft in the non-riding state, and the rear arm of the rear arm is provided with a straight line extending from the pivot shaft to the rear axle. A bracket that extends in the extension direction of the vehicle is fixed near the center of the vehicle width direction, and a trailer towing coupling device is provided on this bracket, so when the driver descends from the vehicle and attaches or detaches the trailer, the position of the pivot shaft becomes higher. The rear arm and the bracket rotate about the rear axle, and the position of the rear end of the bracket is lowered. That is, the traction device moves downward from the rear fender. For this reason, the space that is opened rearward from between the driving seat and the rear arm is largely opened rearward, and the workability of attaching and detaching the trailer is improved. In addition, when the driver gets on the vehicle, the pivot shaft becomes lower, the rear arm and the bracket integrated with the rear arm rotate in the opposite direction to that at the time of getting off, and the coupling device is located substantially behind the rear axle and at substantially the same height as the pivot shaft. As a result, the trailer's towing load is less likely to affect the driving posture of the vehicle. Furthermore, while the bracket is placed near the center of the vehicle width direction, the gear case is deviated in the vehicle width direction so as not to interfere with this bracket.Therefore, when installing the bracket, make the bracket sufficiently short without worrying about the gear case. The coupling device can be brought closer to the rear axle. Therefore, the influence of the vertical force exerted on the rear arm and the trailer on each other is reduced. That is, the vertical swing amount of the trailer due to the vertical swing of the rear arm is reduced, and conversely, the vertical swing of the trailer towing rod has less effect on the driving posture of the vehicle.

[Brief description of drawings]

FIG. 1 is a side view in which an embodiment of the present invention is partially sectioned, and FIG.
FIG. 3 is a plan view of an essential part, and FIG. 3 is a sectional view taken along line III-III in FIG. 34 …… engine, 44 …… rear arm, 46 …… pivot, 48 …… rear axle, 50 …… rear wheel, 53 …… cushion unit, 60 …… gear case, 62 …… final reduction gear, 64 …… drive Shaft, 76 ... Bracket, 78 ... Protrusion as coupling device, 80 ... Trailer.

Claims (1)

[Claims] 1. An engine mounted in the vicinity of the center of a vehicle body, and a rear arm capable of swinging up and down, the front end of which is pivotally attached to a frame near the rear portion of the engine by a pivot shaft and the rear end of which has a rear cylinder in the vehicle width direction. A cushion unit that is bridged between the frame and the rear arm, a gear case that is arranged in parallel with the rear cylinder at the rear end of the rear arm in the vehicle body width direction and accommodates a final reduction gear, and the gear case and the rear cylinder. A rear axle that penetrates and has rear wheels attached to both ends, a drive shaft that is inserted into the rear arm and that transmits the output of the engine to the rear axle via the final reduction gear, and is long at the upper part of the vehicle body in the front-rear direction. In a vehicle for traveling on a wasteland, which includes a straddle-type operation seat and has a space that opens rearward between the rear arm and the operation seat, in a state where the rear arm is not in a riding state, While inclining so that it is lower than the pivot shaft, the gear case is eccentrically arranged in the width direction of the vehicle body, and extends in a straight line from the pivot shaft to the rear axle to the rear cylinder near the center of the vehicle width direction. A vehicle for running on rough terrain, characterized in that a bracket that extends in the same direction is fixed, and that this bracket is provided with a connecting device for towing a trailer.