JPH10152076A - Crawler belt driving mechanism for crawler type vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a crawler type vehicle excellent in drivability and maneuverability. SOLUTION: A crawler type truck 1 employs a four-wheel drive system consisting of a front driving sprocket 12 and a rear driving sprocket 13. No deflection is generated at the part on the running surface side of a crawler belt 14, therefore, it is possible to improve road surface gripping force. Use of a hydraulic four-wheel steering system makes steering characteristics very good. Driving sprockets 12, 13 are supported by a truck frame 11, which retain the crawler belt 14 completely. A truck roller 17 is formed with a free sprocket 17C, thus it is possible to prevent the part on the running surface side of the crawler belt 14 from being derailed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crawler type vehicle, and more particularly to a mechanism capable of improving the driving performance of the vehicle.

[0002]

2. Description of the Related Art A crawler track has a pair of left and right crawler belts which are bridged between a front driving sprocket and a rear driven sprocket to form an endless track. The trajectory of each crawler belt on the traveling road surface side is supported by a plurality of track rollers supported to be vertically swingable with respect to a track frame (body frame). As described above, the crawler track generally adopts a two-wheel drive system.
In general, a two-wheel steering system is employed as the steering system.

[0003]

The crawler track having such a structure has the following problems to be solved.

[0004] First, the crawler belt is driven by a front drive sprocket. In this driving mode, the crawler belt is pulled to the front side via the rear driven sprocket. For this reason, the portion of the crawler belt between the driving sprocket and the driven sprocket that is in contact with the traveling road surface is likely to be bent. As a result, the road surface grip force of the crawler belt and the like may be reduced, and the driving performance may be reduced.

Second, the steering performance of a crawler truck is lower in operability and responsiveness than a general vehicle.

Third, the driven sprockets are attached to both ends of a rear drive shaft extending in the vehicle width direction. If the rear drive shaft bends up and down, the crawler belt stretched over the left and right driven sprockets is likely to come off.

Fourth, in the crawler belt, a portion between the driving sprocket and the driven sprocket is supported by a track roller. However, when the road surface has many irregularities, or when the vehicle travels across an inclined surface, the crawler belt may be disengaged from the track roller in the vehicle width direction, that is, derailment may occur. In particular, when the vehicle travels across an inclined surface, the crawler belt on the valley side (lower side) is likely to lose wheel.

An object of the present invention is to propose a crawler belt driving mechanism for a crawler type vehicle which can solve such a conventional problem.

[0009]

In order to solve the above-mentioned problems, the crawler-type vehicle of the present invention employs a four-wheel drive system as a drive system of the crawler belt. That is, a front propeller shaft whose rear side is connected to the engine via a transmission, a front drive shaft extending in the vehicle width direction connected to the front side of the front propeller shaft via a front differential, and a front side A pair of left and right front drive sprockets fixed to both ends of the drive shaft, a rear propeller shaft whose front side is connected to the engine via a transmission, and a rear differential connected to the rear side of the rear propeller shaft. A rear drive shaft extending in the vehicle width direction, a pair of left and right rear drive sprockets fixed to both ends of the rear drive shaft, a right crawler belt bridged over the right front and rear sprockets, Front and rear sprockets And a four-wheel drive mechanism having a left crawler belt hung on.

[0010] In the crawler belt driving mechanism of the crawler type vehicle according to the present invention, the crawler belt is driven at positions before and after the crawler belt. Does not occur. Therefore, the driving performance can be improved by increasing the road surface grip force.

Next, in the crawler type vehicle according to the present invention, the front sprocket and the rear sprocket are configured to be supported by a front end and a rear end of a track frame extending in the front-rear direction of the vehicle body at both sides in the vehicle width direction. . With this configuration, the sprocket is supported by the drive shaft and also by the track frame. Therefore, the sprocket is always supported at a fixed position, and the crawler belt does not come off from there.

On the other hand, in the crawler type vehicle according to the present invention, a free sprocket is disposed between a pair of track rollers supported via a swing arm at a middle position of the track frame in the vehicle longitudinal direction,
The free sprocket is located between two teeth formed on the inner peripheral surface of the crawler belt. By employing this configuration, the free sprocket prevents the crawler belt from coming off the wheel.
Therefore, when traveling on a road surface with a lot of unevenness or traveling on an inclined surface, the crawler belt can be prevented from coming off the wheel.

Further, the crawler type vehicle of the present invention employs a hydraulic four-wheel steering mechanism. That is,
A pair of front skid disks attached to both sides of the front drive shaft; a pair of rear skid disks attached to both sides of the rear drive shaft; and And a hydraulic circuit for applying a steering braking force to the rear skid disc and a hydraulic circuit for applying a steering braking force to the left front and rear skid discs. According to the present invention thus configured, the operability at the time of steering is improved,
In addition, responsiveness is improved because of four-wheel steering.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A crawler track to which the present invention is applied will be described below with reference to the drawings.

FIG. 1A shows the appearance of the crawler type track of this embodiment. As shown in this figure, the crawler track 1 is composed of a vehicle body 2 and a crawler drive mechanism 3 attached to the bottom surface thereof. The crawler drive mechanism 3 includes a pair of right and left crawlers 4 and 5 having the same configuration.

As shown in FIG. 1B, the crawler 4
A track frame 11 extending in the vehicle longitudinal direction, and a front drive sprocket 12 supported on the front side
And a rear drive sprocket 1 supported on the rear side
3 and a crawler belt 14 spanned between these sprockets. Also, track frame 1
1, a track roller set 15 to 19 are supported on the lower side thereof via a swing arm, and a track roller set 20 is also supported at an upper middle position in the vehicle longitudinal direction. The sprockets 12 and 13 and the track roller sets 15 to 20 form an endless track of the crawler belt 14. Since the crawler 5 on the other side has the same structure, its description is omitted.

As shown in FIG. 1 (C), the track roller set 17 located in the middle of the front and rear direction of the vehicle body among the track roller sets on the lower side of the track frame 11 has a predetermined interval in the vehicle width direction. A pair of track rollers 17 arranged at
A, 17B, and a free sprocket (idling sprocket) 17C disposed between these rollers. The crawler belt 14 has a configuration in which a metal core is covered with rubber.
The tooth-like projections 14A and 14B are formed. The free sprocket 17C is located between these two teeth 14A, 14B.

FIG. 2 shows a four-wheel drive mechanism and a hydraulic four-wheel steering mechanism of the crawler truck 1 of the present embodiment. First, the four-wheel drive mechanism will be described. The rotation of the engine 31 attached to the vehicle body frame is connected via a transmission 32 to a rear propeller shaft 33 extending coaxially toward the rear of the vehicle body. A rear end of the rear propeller shaft 33 is a rear differential 34.
Through the rear drive shaft 35. At the left and right ends of the rear drive shaft 35, respectively, a rear drive sprocket 1
3A and 13B are fixed.

Similarly, the transmission 32 is connected to a front propeller shaft 41 extending forward of the vehicle body. The front end of the front propeller shaft 41 is connected to a front drive shaft 43 via a front differential 42. At both ends of the front drive shaft 43, front drive sprockets 12A,
2B is fixed.

Next, the hydraulic four-wheel steering mechanism will be described.
The rotation of the shaft of the steering wheel 51 arranged in the driver's seat of the vehicle body is transmitted to a steering gear box 52 composed of a rack and pinion, and is transmitted to a steering arm 53 via this. Rocks. The left and right ends of the steering arm 53 are connected to a left steering master cylinder 54 and a right steering master cylinder 55, respectively. The swing of the steering arm 53 is converted into a hydraulic driving force.

The hydraulic pressure from the left steering master cylinder 54 is transmitted to front and rear skid disc braking pads 57, 58 via a steering hose 56. The skid disks 59, 60 are attached to the front left and right drive shafts. These skid disks 59,
A brake is applied to the brake pad 60 by applying hydraulic pressure to the brake pads 57 and 58.

Similarly, the hydraulic pressure from the right steering master cylinder 55 is transmitted to the front and rear skid disc braking pads 62 and 63 via the steering hose 61. The skid disks 64 and 65 are attached to the front left and right drive shafts. These skid disks 64, 65 are braked by applying hydraulic pressure to the braking pads 62, 63.

[0023]

As described above, the following effects can be obtained in the crawler type vehicle of the present invention.

First, a four-wheel drive system is adopted as a crawler belt drive system. Therefore, since the crawler belt 14 is driven at a position before and after the crawler belt 14, the portion of the crawler belt 14 in contact with the road surface does not bend. For this reason, the road performance can be improved by increasing the road surface grip force.

Second, the front drive sprocket 12
And the rear drive sprocket 13 is mounted on the track frame 1 extending in the vehicle longitudinal direction at both sides in the vehicle width direction.
1 is supported by the front end and the rear end, respectively. Therefore, the sprockets 12 and 13 are
Track frame 1 supported by 3, 35
1 is also supported. Therefore, the sprocket is always supported at a fixed position, and the crawler belt 14 does not come off from there.

Third, a free sprocket 17C is disposed between a pair of track rollers 17A and 17B supported via a swing arm at a position on the track frame 11 at an intermediate position in the vehicle longitudinal direction. 17C is located between the two teeth 14A, 14B formed on the inner peripheral surface of the crawler belt 14. Therefore, the free sprocket 1
7C prevents the crawler belt 14 from coming off.
As a result, it is possible to prevent the crawler belt 14 from falling off when traveling on a road surface having a lot of irregularities or traveling on an inclined surface.

Fourth, a hydraulic four-wheel steering mechanism is employed. Accordingly, the operability at the time of steering is improved, and the responsiveness is also improved due to the four-wheel steering.

[Brief description of the drawings]

1A is a schematic perspective view showing a crawler track to which the present invention is applied, FIG. 1B is a schematic side view showing one crawler, and FIG. 1C is a portion of the crawler cut along a line CC. FIG.

FIG. 2 is a schematic configuration diagram showing a four-wheel drive mechanism and a four-wheel steering mechanism assembled in a crawler track in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Crawler type track 2 Body 3 Crawler type drive mechanism 4, 5 Crawler 11 Track frame 12 Front drive sprocket 13 Rear drive sprocket 14 Crawler belt 17 Track roller 17C Free sprocket

Claims (4)

[Claims] A front propeller shaft having a rear side connected to an engine via a transmission; a front drive shaft extending in a vehicle width direction connected to a front side of the front propeller shaft via a front differential; A pair of left and right front drive sprockets fixed to both ends of the front drive shaft, a rear propeller shaft whose front side is connected to the engine via a transmission, and a rear differential on the rear side of the rear propeller shaft. A connected rear drive shaft extending in the vehicle width direction; a pair of left and right rear drive sprockets fixed to both ends of the rear drive shaft; and a right side bridged over the right front and rear drive sprockets. Crawler belt and the left front Crawler belt drive mechanism of a crawler type vehicle, characterized in that it comprises a four-wheel drive mechanism having a left crawler belt hung sprocket for the rear. 2. The vehicle according to claim 1, wherein the front drive sprocket and the rear drive sprocket are respectively supported by a front end and a rear end of a track frame extending in the vehicle longitudinal direction at both sides in the vehicle width direction. A crawler belt drive mechanism for a crawler-type vehicle. 3. The free sprocket according to claim 2, wherein a free sprocket is disposed between a pair of track rollers supported via a swing arm at a position about the center of the track frame in the longitudinal direction of the vehicle. Are located between two tooth-shaped projections formed on the inner peripheral surface of the crawler belt, and the free sprocket prevents the crawler belt from derailing. Crawler belt drive mechanism for crawler-type vehicles. 4. The steering wheel according to claim 1, wherein a pair of front skid disks mounted on both sides of the front drive shaft, a pair of rear skid disks mounted on both sides of the rear drive shaft, and operation of a steering wheel. A hydraulic circuit that applies a steering braking force to the front and rear skid disks on the right side in conjunction with
A crawler belt drive mechanism for a crawler-type vehicle, comprising: a four-wheel operation mechanism having a hydraulic circuit for applying a steering braking force to the left-side front and rear-side skid disks.