JPH07277231A - Tire-driving crawler travel gear - Google Patents

Abstract

PURPOSE:To prevent localized wear with the ground plane of an endless-belt- shaped crawler main body offset to one side of the belt width by balancing ground pressures along the belt width of the crawler main body. CONSTITUTION:In a tire-driving crawler travel gear in which a crawler main body 7 in the form of an endless belt is wound to a plurality of tires 14 in such a way that the tires 14 are offset to one side of the belt width A of the crawler main body 7, either the side wall portion 20 of each tire 14 is provided with greater rigidity at the other side of the belt width A of the crawler main body than at the former side of the belt width A of the crawler main body, or the tread 15a of each tire 14 is formed into a slope that inclines from one side of the belt width A of the crawler main body to an end at the other side so as to extend inwards along the radial direction of the tire.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire-driven crawler traveling device.

[0002]

2. Description of the Related Art Conventionally, as a tire drive type crawler traveling device, there is one disclosed in Japanese Patent Laid-Open No. 3-246177. This is a vehicle in which a guide wheel is provided between a rear wheel and a front wheel of the vehicle, and an endless belt-shaped crawler body made of an elastic material is hung across the guide wheel and the rear wheel.

[0003]

In the above conventional one, as shown in FIG. 7, the rear wheel 31 and the guide wheel 32 are
For example, in the case of being offset inward in the band width direction with respect to the crawler body 33, the center of gravity of the load acting on the crawler body 33 is biased inward from the central portion in the band width direction, and the band width of the crawler body 33 is There is a problem that the ground contact pressure on the inner side is higher than the outer side in the direction, so that the inner side 34a of the ground contact surface 34 of the crawler body 33 is unevenly worn, which affects durability.

On the other hand, as shown in FIG. 8, even if the rear wheel 31 and the guide wheel 32 are not offset to one side in the band width direction with respect to the crawler body 33, the rear wheel 31 and the guide wheel 32 are When the thrust force f acts, the ground surface 34 of the crawler body 33 is unevenly worn on the front side 34a in the acting direction of the thrust force f. When the thrust force f acts on the rear wheel 31 and the guide wheel 32 described above, the rear wheel 31 and the guide wheel 32 are usually set so that the tire centers are aligned in the vertical direction. Since the tension applied to the crawler body 34 in the circumferential direction with respect to 32 is not uniform in the band width direction of the crawler body 33, it is conceivable that the wheels 31 and 32 are provided with the same negative camber or positive camber. . In the case of the negative camber, the inner side of the crawler body in the band width direction is unevenly worn, and in the case of the positive camber, the outer side is unevenly worn.

In view of the above problems, the present invention balances the ground contact pressure in the band width direction of the crawler body to prevent the uneven wear of the ground surface of the crawler body biased to one side in the band width direction. The purpose is to make the ground pressure uniform.

[0006]

The first technical means taken by the present invention to achieve the above object is to provide an endless belt-shaped crawler body made of an elastic material over a plurality of tires. In a tire-driven crawler traveling device mounted so as to be offset to one side in the crawler body band width direction, the rigidity of the sidewall portion of the tire on the other side in the crawler body band width direction is set to one side in the crawler body band width direction. It is larger than the side wall part.

A second technical means is a tire mounted on an endless belt-shaped crawler body made of an elastic material so that the tire is offset to one side in the band width direction of the crawler body. In the drive type crawler traveling device,
The tread surface of the tire is provided with an inclined surface that is inclined so as to move inward in the tire radial direction from the other side in the width direction of the crawler body toward one end.

A third technical means is a tire drive type crawler traveling device in which an endless belt-shaped crawler main body made of an elastic material is hung over a plurality of tires, and an arbitrary axial position is provided on a tread surface of the tire. Is located at the point where the inclined surface is provided so as to move inward in the tire radial direction from the end to the end in the acting direction of the thrust force acting on the tire.

A fourth technical means is a tire drive type crawler traveling device in which an endless belt-shaped crawler main body made of an elastic material is hung over a plurality of tires.
The rigidity of the side wall portion on the rear side in the acting direction of the thrust force acting on the tire is larger than that of the side wall portion on the front side in the acting direction of the thrust force.

[0010]

In the invention of claim 1, the crawler main body is mounted on a plurality of tires so that the tire is offset to one side in the band width direction of the crawler main body.
Since the rigidity of the side wall portion on the other side in the width direction of the crawler main body is made higher than that of the side wall portion on the one side in the width direction of the crawler main body, the side opposite to the load below the side wall portion on the offset side The load on the lower side of the side wall of the crawler becomes larger, and the center of gravity of the load moves to the central part of the crawler body in the band width direction. Uniform pressure can be achieved.

According to the second aspect of the present invention, the tread surface of the tire is provided with an inclined surface that is inclined so as to move inward in the tire radial direction from the other side in the width direction of the crawler body toward one end. As a result, similarly to the above, the ground pressure in the band width direction of the crawler body is balanced, and the ground pressure can be made uniform. According to the third aspect of the invention, the tread surface of the tire is provided with an inclined surface that is inclined so as to move inward in the tire radial direction from an arbitrary position in the axial direction toward the end portion in the acting direction of the thrust force acting on the tire. By providing the ground pressure, the ground pressure can be balanced in the band width direction of the crawler body, and the ground pressure can be made uniform.

According to the fourth aspect of the present invention, the rigidity of the sidewall portion of the tire on the rear side in the acting direction of the thrust force acting on the tire is made larger than that of the sidewall portion on the front side in the acting direction of the thrust force. The ground pressure in the band width direction of the crawler body is balanced, and the ground pressure can be made uniform.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 2, reference numeral 1 denotes a light track type semi-crawler type vehicle in which tire-driven crawler traveling devices 2 are mounted on the left and right sides of the rear part of the vehicle body, and the left and right front wheels 3 are steering wheels.
At least the left and right rear wheels 4 are drive wheels, and a guide wheel 5 is provided between the left and right front wheels 3 and the rear wheels 4. In the crawler traveling device 2, the elastic crawler 6 is provided with a rear wheel 4 and a guide wheel 5.
It is mainly constructed by hanging over.

As shown in FIGS. 1 and 3, the elastic crawler 6 is provided with an endless crawler body 7 made of an elastic material such as rubber, and a lug 8 is circumferentially provided on the grounding surface 7a side of the crawler body 7. Are formed integrally at a predetermined interval on the inner peripheral surface 7
b is formed so as to be a flat surface in the band width direction, and on the inner peripheral surface 7b side thereof, the rear wheels 4 and the guide wheels 5 are located on both sides in the axial direction (left-right direction) and the wheels 4 and 5 are removed. A pair of left and right guide protrusions 9 and 10 for preventing a ring are integrally formed at a predetermined interval in the circumferential direction.

In the crawler body 7, the crawler body 7 made of a hard material has a core metal 1 in the band width direction (left-right direction) A.
1 are embedded at a predetermined interval in the circumferential direction, and the core metal 11 is arranged at a position corresponding to the guide protrusions 9 and 10. Further, in the crawler body 7, a tensile body 12 is embedded in which a large number of circumferentially endless steel cords are arranged in the band width direction A.

Each of the rear wheels 4 and the guide wheels 5 is formed by mounting a pneumatic tire 14 made of rubber on a wheel 13. Tire 14
Is a pair of axially inner and outer bead portions 19 in which a tread portion 15 that can come into contact with the road surface, a bead wire 16 and a bead filler 17 are embedded and fixed to a rim 18 of the wheel 13, and the tread portion 15 and the bead portion. A pair of axially inner and outer side wall portions 20 positioned between the portions 19;
It is mainly configured by a carcass 21 provided from one bead portion 19 to the other bead portion 19. In addition,
The sidewall portion 20 further includes a shoulder portion 20a on the tread portion 15 side and a side portion 20 on the bead portion 19 side.
and b.

The rear wheel 4 and the guide wheel 5 are attached to the axle so that the tire center line (a line segment in the tire radial direction passing through the axial center of the tire) O is aligned in the vertical direction, and the rear wheel 4 and the guide wheel 5 are offset from the crawler body 7 inward in the band width direction A of the crawler body 7.
Therefore, normally, the ground contact pressure inside the ground contact surface 7a of the crawler main body 7 (and the ground contact surface of the lug 8) in the band width direction A is higher than that at the outer side, and uneven wear is caused. Eliminates uneven wear.

That is, as a first means, the structure of the side wall portion 20 on the outer side in the axial direction is strengthened to increase the rigidity of the side wall portion 20. The following method can be considered as a method of increasing the rigidity of the sidewall portion 20. The thickness of the sidewall portion 20 is increased. The hardness of the rubber material of the sidewall portion 20 (carcass 2
The hardness of the rubber layer on the outer side of 1 and / or the inner liner on the inner side of the carcass 21 is increased. The length of the winding portion 21A of the carcass 21 is increased. The height of the bead filler 17 is increased (the vertical length is increased) or the size thereof is increased. Increase the hardness of the bead filler 17.

The above items (1) to (3) are combined on a case-by-case basis, but they may be used independently. In addition, as a second means, the tread surface 15A is
It is formed on an inclined surface that is inclined at an angle α with respect to a surface orthogonal to the tire center line O so as to move inward in the tire radial direction from the outer end portion in the band width direction A toward the inner end portion.

When the load from the vehicle body side acts on the tire 14, the load acting on the lower side of the outer side wall portion 20 of the tire 14 is applied to the inner side by applying the first and second means individually or in combination. It becomes larger than the load acting below the sidewall portion 20, and the center of gravity of the load moves to the central portion in the band width direction of the crawler body 7 as shown by the load distribution B shown by the solid line in FIG.
The ground pressure of the crawler body 7 in the band width direction A is balanced, and the ground pressure of the crawler body 7 is made uniform. Figure 4
The load distribution C shown by a virtual line in FIG.

When the first and second means are used in combination, each complements the other function, and
In the means of, for example, the sidewall portion 2 is excessively
There is no need to increase the wall thickness of 0, and the second means has an effect that it becomes unnecessary to take α too large. In addition, in FIG. 1, the entire tread surface 15A is an inclined surface, but the present invention is not limited to this, and the starting point D of the inclined surface is, as shown in FIG. Alternatively, it may be at any position in the tire axial direction, and the inclination angle α is preferably set within 10 ° in consideration of the wall thickness of the tread portion 15.

The first and second means are also adopted when the thrust force acts on the rear wheel 4 and the guide wheel 5. That is, as shown in FIG. 6, for example, since the tension in the circumferential direction of the crawler body 7 is not uniform in the crawler body 7 band width direction A, it is the same as when the tire 14 is provided with a negative camber. In the normal case, a normal thrust force F acts on the tire 14 inward,
Although the ground contact pressure of the crawler body 7 is larger on the inner side than the outer side in the band width direction, the ground pressure in the band width direction A of the crawler body 7 is balanced by the first and second means. The ground pressure can be made uniform.

Further, when the second means is adopted, an angle corresponding to the camber angle given to the tire 14 is measured and the angle is adopted as α. Further, when the thrust force acts axially outward of the tire 14, the inclined surface provided to the tread surface 15a is inclined so as to move inward in the tire radial direction as it goes outward in the axial direction of the tire. The inside of the sidewall portion 20 has increased rigidity.

In the present invention, since the structure of the tire is changed, it can be carried out relatively easily, and a troublesome modification on the vehicle body side such as changing the tire mounting angle is unnecessary.

[0025]

According to the present invention, the crawler body is mounted on a plurality of tires so that the tire is offset to one side in the band width direction of the crawler body. The rigidity of the side wall on the other side is set to be greater than that of the side wall on the one side in the crawler body band width direction, so that the load acting below the side wall on the offset side is lower than the side wall on the opposite side. The load acting on one side becomes larger, and the center of gravity of the load moves to the central portion in the band width direction of the crawler body, which balances the ground pressure in the band width direction of the crawler body and makes the ground pressure uniform. Can be realized.

Further, by providing an inclined surface on the tread surface of the tire so as to move inward in the tire radial direction from the other side in the band width direction of the crawler body toward the one side end, the crawler body is similar to the above. The grounding pressure in the band width direction of B can be balanced, and the grounding pressure can be made uniform.
Further, the tread surface of the tire is provided with an inclined surface that is inclined so as to be moved inward in the tire radial direction from the arbitrary position in the axial direction toward the end in the acting direction of the thrust force acting on the tire, or , The ground contact in the band width direction of the crawler main body is made by making the rigidity of the side wall portion of the tire rearward in the acting direction of the thrust force acting on the tire larger than that of the side wall portion forward in the acting direction of the thrust force. The pressure is balanced and the ground pressure can be made uniform.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a crawler traveling device according to an embodiment.

FIG. 2 is a side view of a vehicle equipped with a crawler traveling device.

FIG. 3 is a side view of the crawler traveling device.

FIG. 4 is a schematic diagram showing a relationship between a crawler traveling device and load distribution.

FIG. 5 is a schematic sectional view of a tire showing another embodiment.

FIG. 6 is a sectional view of a crawler traveling device showing another embodiment.

FIG. 7 is a schematic sectional view of a crawler traveling device according to a conventional example.

FIG. 8 is a schematic sectional view of a crawler traveling device according to a conventional example.

[Explanation of symbols]

 4 Rear Wheel 5 Guide Wheel 14 Tire 15a Tread Surface 20 Sidewall

Claims (4)

[Claims] 1. A tire-driven crawler traveling device mounted on an endless belt-shaped crawler main body made of an elastic material, so that the tires are offset to one side in the band width direction of the crawler main body over a plurality of tires. A tire-driven crawler traveling device, characterized in that the rigidity of a side wall portion of the tire on the other side in the crawler body band width direction is set to be higher than that of a side wall portion on one side of the crawler body band width direction. 2. A tire-driven crawler traveling device mounted on an endless belt-shaped crawler main body made of an elastic material, so that the tires are offset to one side in the band width direction of the crawler main body over a plurality of tires. A tire driven crawler, wherein the tread surface of the tire is provided with an inclined surface that is inclined so as to move inward in the tire radial direction from the other side in the crawler body band width direction toward one end. Traveling device. 3. A tire drive type crawler traveling device in which an endless belt-shaped crawler body made of an elastic material is hung over a plurality of tires, and the tread surface of the tire acts on the tire from any position in the axial direction. A tire-driven crawler traveling device comprising an inclined surface that is inclined so as to move inward in the tire radial direction toward the end of the direction in which the thrust force acts. 4. A tire drive type crawler traveling device in which an endless belt-shaped crawler main body made of an elastic material is hung over a plurality of tires, wherein a side of the tire on the rear side in the acting direction of a thrust force acting on the tires. A tire-driven crawler traveling device in which the rigidity of the wall portion is larger than that of the side wall portion on the front side in the acting direction of the thrust force.