JP2021037849A - Elastic crawler and core material - Google Patents

Abstract

To provide an elastic crawler capable of suppressing derailment caused by bending, torsion or the like while suppressing an increase in the weight of a core material.SOLUTION: An elastic crawler 1 includes an endless belt-like crawler body 2 formed from an elastic body and a core material 3 arranged, being spaced in a crawler peripheral direction X in the crawler body 2 and formed from a harder material than the elastic body. The core material 3 includes a core material body 3 extending in a crawler width direction Y and a plurality of derailment prevention protrusions 8 protruding from a first end face S1 and a second end face S2 in the crawler peripheral direction X of the core material body 3, respectively. Each of the derailment prevention protrusions 8 is formed with at least one groove part 9 extending in the crawler peripheral direction X.SELECTED DRAWING: Figure 2

Description

The present invention relates to an endless strip-shaped elastic crawler and a core material for the elastic crawler.

Conventionally, an elastic crawler in which a plurality of core materials are embedded in a crawler body made of an elastic body such as rubber is known. The core material functions as a reinforcing material in the crawler width direction and is embedded at intervals in the crawler circumferential direction. Further, the tension body functions as a reinforcing material in the circumferential direction of the crawler, and is composed of a cord extending in the circumferential direction of the crawler through the outer peripheral side of the crawler from the core material. In this type of elastic crawler, there is a problem that a deviation occurs in the crawler width direction between adjacent core materials, and the core material causes the rolling wheels of the vehicle body to come off, causing derailment.

Patent Document 1 below describes that the core material is provided with a pair of first protrusions protruding on one side in the circumferential direction of the crawler and a pair of second protrusions protruding on the other side in order to prevent derailment. Has been done. In this elastic crawler, the first protrusion of the core material on one side adjacent to each other in the circumferential direction of the crawler overlaps with the second protrusion of the core material on the other side in the crawler width direction, so that the deviation in the crawler width direction between the core materials is caused. It is suppressed.

JP-A-2019-93878

However, if bending or twisting occurs between adjacent core materials due to an external force acting when riding on a protrusion or turning, the first protrusion and the second protrusion are disengaged and elastic. The crawler may come off from the drive wheels, idle wheels, rolling wheels, etc. on the vehicle body side. As a measure against derailment caused by such bending or twisting, it is proposed to increase the size of the first protrusion and the second protrusion, but this will lead to an increase in the weight of the core material, and further improvement can be made. It was desired.

The present invention has been devised in view of the above circumstances, and a main object of the present invention is to provide an elastic crawler capable of suppressing derailment due to bending, twisting, etc. while suppressing an increase in the weight of the core material. There is.

The present invention is an elastic crawler, which is an endless band-shaped crawler body made of an elastic body, and a core material made of a material that is arranged in the crawler body at intervals in the crawler circumferential direction and is harder than the elastic body. The core material includes a core material body extending in the crawler width direction, and a plurality of derailment prevention protrusions protruding from the first end surface and the second end surface of the core material body in the crawler circumferential direction. Each of the derailment prevention protrusions is characterized in that at least one groove extending in the circumferential direction of the crawler is formed.

In the elastic crawler of the present invention, the derailment prevention protrusions are a pair of first protrusions protruding from the first end surface and a pair of core materials protruding from the second end face and adjacent to each other in the crawler circumferential direction. A pair of second protrusions that can enter between the one protrusions are included, and the first protrusion is a crawler of the second protrusion of the core material whose first surface inside in the crawler width direction is adjacent in the crawler circumferential direction. It is arranged so as to face the second outer surface in the width direction, and the groove portion includes a first groove portion formed on the first surface and a second groove portion formed on the second surface. desirable.

In the elastic crawler of the present invention, when an external force that twists the pair of core members adjacent to each other in the circumferential direction of the crawler acts on the crawler body, the first groove portion is formed on the second surface of the second surface facing the crawler body. It is desirable that the second groove portion meshes with the portion that is not the groove portion, and the second groove portion meshes with the portion of the first surface that faces the surface that is not the first groove portion.

The elastic crawler of the present invention further includes a tension body composed of a cord arranged in the crawler body and extending in the crawler circumferential direction through the crawler outer peripheral side from the core material, and further includes a crawler outer circumference of the derailment prevention protrusion. It is desirable that the side portion is located on the outer peripheral side of the crawler with respect to the tension body.

The present invention is a core material used for an elastic crawler, in which a core material main body extending in the crawler width direction and a plurality of derailment preventions protruding from the first end surface and the second end surface of the core material main body in the crawler circumferential direction, respectively. Each of the derailment prevention protrusions, including the protrusions, is characterized in that at least one groove extending in the circumferential direction of the crawler is formed.

In the core material of the present invention, the derailment prevention protrusions are a pair of first protrusions protruding from the first end surface and a pair of the first protrusions protruding from the second end face and arranged in the crawler circumferential direction. The groove includes a pair of second protrusions that can enter between the one protrusions, the first groove formed inside the first protrusion in the crawler width direction, and the outside of the second protrusion in the crawler width direction. It is desirable to include a second groove formed in.

In the core material of the present invention, it is desirable that the first groove portion and the second groove portion have the same cross-sectional shape.

In the core material of the present invention, it is desirable that one groove portion is formed in each of the derailment prevention protrusions.

In the core material of the present invention, it is desirable that a plurality of the groove portions are formed in each of the derailment prevention protrusions.

In the core material of the present invention, it is desirable that the outer end portion of the derailment prevention protrusion on the outer peripheral side of the crawler is located on the outer peripheral side of the crawler rather than the outer surface of the outer peripheral side of the crawler of the core material body.

In the elastic crawler according to the present invention, at least one groove extending in the circumferential direction of the crawler is formed in each of the derailment prevention protrusions. In such an elastic crawler, even when bending or twisting occurs between adjacent core materials, the grooves are engaged with each other, so that the derailment prevention protrusions are less likely to come off. Therefore, the elastic crawler of the present invention can suppress derailment while suppressing an increase in the weight of the core material.

In the core material according to the present invention, at least one groove extending in the circumferential direction of the crawler is formed in each of the derailment prevention protrusions. In such a core material, even when bending or twisting occurs between adjacent core materials, the grooves are engaged with each other, so that the derailment prevention protrusions are less likely to come off. Therefore, the core material of the present invention can suppress derailment while suppressing an increase in weight.

It is a perspective view which shows one Embodiment of the elastic crawler of this invention. It is a perspective view of the core material arranged in the crawler circumferential direction. It is a front view of a core material. It is a top view of the core material arranged in the crawler circumferential direction. It is sectional drawing of the line AA of FIG. FIG. 5 is a cross-sectional view when a twist occurs between adjacent core materials in FIG. It is sectional drawing of the derailment prevention protrusion of another embodiment. FIG. 7 is a cross-sectional view when a twist occurs between adjacent core materials in FIG. 7.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view showing an elastic crawler 1 of the present embodiment. As shown in FIG. 1, the elastic crawler 1 of the present embodiment includes an endless band-shaped crawler body 2 made of an elastic body such as rubber, a plurality of core materials 3 arranged in the crawler body 2, and a crawler body 2. It contains a tension body 4 arranged inside. It is desirable that the tension body 4 is composed of a cord extending in the crawler circumferential direction X through the crawler outer peripheral side Zo rather than the core material 3.

In the present specification, the crawler circumferential direction X is the rotation direction of the elastic crawler 1, and corresponds to the direction indicated by the reference numeral X in FIG. Further, the crawler width direction Y is the axial direction of the drive wheels when the elastic crawler 1 is mounted on the vehicle, and corresponds to the direction indicated by the reference numeral Y in FIG. Further, the crawler thickness direction Z is a direction orthogonal to the crawler circumferential direction X and the crawler width direction Y, and corresponds to the direction indicated by the reference numeral Z in FIG. In the crawler thickness direction Z, the inside of the endless band-shaped elastic crawler 1 is the crawler inner peripheral side Zi, and the outside is the crawler outer peripheral side Z.

The crawler body 2 of the present embodiment has a substantially constant width and extends continuously in the crawler circumferential direction X. On the outer surface 2o of the crawler outer peripheral side Z of the crawler main body 2, for example, a plurality of lugs 5 arranged at intervals in the crawler circumferential direction X are provided. The lug 5 extends in the crawler width direction Y and is suitable for enhancing traction when traveling on rough terrain.

On the inner surface 2i of the crawler inner peripheral side Zi of the crawler main body 2, for example, two rows of protrusions 6 composed of a plurality of protrusions 6a and extending in the crawler circumferential direction X are formed. For example, drive wheels, idle wheels, rolling wheels, etc. on the vehicle body side are guided between the two rows of protrusion rows 6. It is desirable that the protrusion 6a is reinforced by the guide protrusion 10 provided on the core material 3. Such a protrusion row 6 is useful for suppressing the derailment of the elastic crawler 1.

The core material 3 is preferably used for the elastic crawler 1 and functions as a reinforcing material in the crawler width direction Y. The core material 3 of the present embodiment is arranged in the crawler main body 2 at intervals in the crawler circumferential direction X. Such a core material 3 can be wound around a drive wheel, a floating wheel, or the like on the vehicle body side while maintaining the shape of the crawler body 2.

It is desirable that the core material 3 is made of a material that is harder than the elastic body that constitutes the crawler body 2. As the hard material of the core material 3, for example, a metal material such as steel or cast iron is preferably adopted. The entire core material 3 does not have to be arranged in the crawler main body 2, and a part thereof, for example, the guide protrusion 10 may be exposed from the crawler main body 2.

FIG. 2 is a perspective view of the core members 3 arranged in the crawler circumferential direction X. As shown in FIG. 2, the core material 3 of the present embodiment has a core material main body 7 extending in the crawler width direction Y and the first end surface S1 and the second end surface S2 of the crawler peripheral direction X of the core material main body 7, respectively. It includes a plurality of protruding derailment prevention protrusions 8.

At least one groove 9 extending in the crawler circumferential direction X is formed in each of the derailment prevention protrusions 8 of the present embodiment. In such a core material 3, the groove portion 9 is engaged even when bending or twisting or the like occurs between the adjacent core materials 3 so that external forces in the crawler width direction Y and the crawler thickness direction Z act at the same time. It becomes difficult for the disengagement prevention protrusions 8 to come off. Therefore, the core material 3 of the present embodiment can suppress derailment while suppressing an increase in weight.

Further, the elastic crawler 1 in which such core members 3 are arranged in the crawler circumferential direction X prevents the wheels from coming off by engaging the groove portions 9 even when the above-mentioned bending or twisting occurs between the adjacent core materials 3. It becomes difficult for the protrusions 8 to come off. Therefore, the elastic crawler 1 of the present embodiment can suppress derailment while suppressing an increase in the weight of the core material 3.

FIG. 3 is a front view of the core material 3 seen from the crawler circumferential direction X, and FIG. 4 is a plan view of the core materials 3 arranged in the crawler circumferential direction X as seen from the crawler inner peripheral side Zi. As shown in FIGS. 3 and 4, as a more preferable embodiment, the core material main body 7 has an engaging portion 7A arranged at the center of the crawler width direction Y and both outer sides of the engaging portion 7A in the crawler width direction Y. Includes a wing portion 7B arranged in. The engaging portion 7A is formed so as to mesh with the tooth groove portion of the drive wheel, for example.

It is desirable that the core material 3 includes a pair of guide protrusions 10 projecting from the inner surface 7i of the crawler inner peripheral side Zi of the core material main body 7 in the crawler thickness direction Z. The guide protrusions 10 stand up on both sides of the engaging portion 7A in the crawler width direction Y, for example. Such a guide protrusion 10 is suitable for guiding by sandwiching a drive wheel, a floating wheel, a rolling wheel, or the like between them.

The derailment prevention protrusion 8 of the present embodiment includes a pair of first protrusions 8A protruding from the first end surface S1 and a pair of second protrusions 8B protruding from the second end surface S2. The pair of first protrusions 8A and the pair of second protrusions 8B are respectively arranged at intervals in the crawler width direction Y, for example. It is desirable that the pair of second protrusions 8B can enter between the pair of first protrusions 8A of the core material 3 adjacent to the crawler circumferential direction X.

In the first projection 8A of the present embodiment, the first surface 8a inside the crawler width direction Y is the second surface 8b outside the crawler width direction Y of the second projection 8B of the core material 3 adjacent to the crawler circumferential direction X. It is arranged facing the.

In such a derailment prevention protrusion 8, even if an external force in the crawler width direction Y acts on the core material 3 adjacent to the crawler circumferential direction X, the first surface 8a on one side and the second surface 8b on the other side are formed. By contacting, lateral displacement between the core materials 3 (deviation in the crawler width direction Y) can be suppressed. Therefore, the derailment prevention projection 8 of the present embodiment can suppress the derailment of the elastic crawler 1.

As shown in FIG. 3, the outer end portion 8o of the crawler outer peripheral side Z of the derailment prevention protrusion 8 of the present embodiment is located on the crawler outer peripheral side Zo with respect to the outer surface 7o of the crawler outer peripheral side Z of the core material main body 7. ing. In the present embodiment, the groove portion 9 is formed at a position including the outer surface 7o of the core material main body 7 in the crawler thickness direction Z. It is desirable that the outer end portion 8o of the derailment prevention protrusion 8 is located on the outer peripheral side Zo of the crawler rather than the tension body 4. Such a derailment prevention protrusion 8 has a smaller range of movement in accordance with bending or twisting between adjacent core members 3, and disengagement between the derailment prevention protrusions 8 is less likely to occur.

As shown in FIGS. 3 and 4, the groove portion 9 is formed inside the first groove portion 9A formed in the crawler width direction Y of the first protrusion 8A and outside the crawler width direction Y of the second protrusion 8B. It is desirable to include the second groove portion 9B. The groove portion 9 of the present embodiment includes a first groove portion 9A formed on the first surface 8a and a second groove portion 9B formed on the second surface 8b.

FIG. 5 is a cross-sectional view taken along the line AA of FIG. As shown in FIG. 5, the first groove portion 9A and the second groove portion 9B of the present embodiment have the same cross-sectional shape. That is, the length L1 of the groove bottom of the first groove portion 9A in the crawler thickness direction Z is equal to the length L2 of the groove bottom of the second groove portion 9B in the crawler thickness direction Z. Further, the length L3 in the crawler thickness direction Z of the portion 8c of the first surface 8a that is not the first groove portion 9A is the length L4 of the portion 8d of the second surface 8b that is not the second groove portion 9B in the crawler thickness direction Z. be equivalent to. Such a groove portion 9 has a good balance when engaged, and is useful for suppressing an increase in the weight of the core material 3.

The groove depth d1 of the first groove portion 9A is preferably 5% to 25% of the width w1 of the first protrusion 8A. If the groove depth d1 of the first groove portion 9A is smaller than 5% of the width w1 of the first protrusion 8A, the groove portions 9 may not engage when bending or twisting occurs between the adjacent core members 3. If the groove depth d1 of the first groove portion 9A is larger than 25% of the width w1 of the first protrusion 8A, the durability of the first protrusion 8A may decrease.

The groove depth d2 of the second groove portion 9B is preferably 5% to 25% of the width w2 of the second protrusion 8B. If the groove depth d2 of the second groove portion 9B is smaller than 5% of the width w2 of the second protrusion 8B, the groove portions 9 may not engage when bending or twisting occurs between the adjacent core members 3. If the groove depth d2 of the second groove portion 9B is larger than 25% of the width w2 of the second protrusion 8B, the durability of the second protrusion 8B may decrease.

The groove depth d1 of the first groove portion 9A of the present embodiment is equal to the groove depth d2 of the second groove portion 9B. Further, the width w1 of the first protrusion 8A is equal to the width w2 of the second protrusion 8B. Such derailment prevention protrusions 8 and groove portions 9 have a good balance when engaged, and are useful for suppressing an increase in the weight of the core material 3.

FIG. 6 is a cross-sectional view when a twist occurs between the adjacent core members 3 in FIG. As shown in FIGS. 1 to 6, when an external force such as twisting acts between the core members 3 adjacent to the crawler circumferential direction X, that is, the external forces in the crawler width direction Y and the crawler thickness direction Z act simultaneously. Occasionally, the first groove portion 9A meshes with a portion 8d of the opposite second surface 8b that is not the second groove portion 9B. Similarly, at this time, the second groove portion 9B meshes with the portion 8c of the facing first surface 8a that is not the first groove portion 9A.

One groove portion 9 of the present embodiment is formed in each of the derailment prevention protrusions 8. At this time, it is desirable that the length L1 of the first groove portion 9A is larger than the length L3 of the portion 8c that is not the first groove portion 9A. Similarly, it is desirable that the length L2 of the second groove portion 9B is larger than the length L4 of the portion 8d that is not the second groove portion 9B. Such a groove portion 9 is likely to engage when a twist occurs between the adjacent core members 3.

FIG. 7 is a cross-sectional view of the derailment prevention protrusion 18 of another embodiment, and FIG. 8 is a cross-sectional view when a twist occurs between the adjacent core members 3 in FIG. 7. The above-described embodiment is the same except for the derailment prevention protrusion 18, and the description thereof will be omitted. FIG. 7 is a cross-sectional view corresponding to FIG. 5, and FIG. 8 is a cross-sectional view corresponding to FIG.

As shown in FIGS. 7 and 8, the derailment prevention projection 18 of this embodiment is the first end surface S1 of the core material 3 (shown in FIG. 2), similarly to the derailment prevention projection 8 of the above-described embodiment. It includes a pair of first protrusions 18A protruding from the core material 3 and a pair of second protrusions 18B protruding from the second end surface S2 (shown in FIG. 2) of the core material 3.

Each of the derailment prevention protrusions 18 of this embodiment is formed with a groove portion 19 extending in the crawler circumferential direction X, similarly to the derailment prevention projection 8 of the above-described embodiment. A plurality of groove portions 19 are formed in each of the derailment prevention protrusions 18, and four grooves are formed in this embodiment.

Also in this embodiment, when an external force such as twisting is applied between the core members 3 adjacent to the crawler circumferential direction X, the first groove portion 19A is a portion 18d of the opposite second surface 18b that is not the second groove portion 19B. Engage. Similarly, at this time, the second groove portion 19B meshes with the portion 18c of the facing first surface 18a that is not the first groove portion 19A.

Since four groove portions 19 of this embodiment are formed, the first protrusion 18A and the second protrusion 18B are engaged with each other in a state where the deviation in the crawler thickness direction Z is smaller than that of the above-mentioned derailment prevention protrusion 8. .. Therefore, even when a twist occurs between the adjacent core materials 3, the deviation of the crawler thickness direction Z between the first protrusion 18A and the second protrusion 18B is suppressed, and the durability of the elastic crawler 1 is improved. Can be done. Further, in the groove portion 19, even when the deviation between the first protrusion 18A and the second protrusion 18B becomes large due to a large external force, some of the groove portions 19 are engaged with each other, so that the derailment prevention protrusion 18 is disengaged. It becomes difficult to do. Therefore, the derailment prevention projection 18 of this embodiment can more reliably suppress derailment.

Although the particularly preferable embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and can be modified into various embodiments.

An elastic crawler having the structure shown in FIG. 1 was prototyped based on the specifications in Table 1. Each prototype crawler was mounted on a traveling device of a small construction machine, and the derailment resistance when a traveling test including riding on a protrusion and turning was performed was evaluated. In the comparative example and the embodiment, the cross-sectional shape and the cross-sectional size of the derailment prevention protrusion are the same except for the groove portion. Therefore, the weight of the core material of the example is smaller than the weight of the core material of the comparative example.

<Wheel resistance>
In the running test, the number of times the elastic crawler was disengaged from the rolling wheels and derailed occurred was measured. The results are displayed in five stages, and the larger the value, the smaller the number of derailments and the better the derailment resistance.

The results of the evaluation are shown in Table 1.

As a result of the evaluation, it was confirmed that the elastic crawler of the example has excellent derailment resistance as compared with the comparative example, and it is possible to suppress derailment while suppressing an increase in the weight of the core material. It was.

1 Elastic crawler 2 Crawler body 3 Core material 7 Core material body 8 Derailment prevention protrusion 9 Groove

Claims (10)

It ’s an elastic crawler,
An endless crawler body made of an elastic body and
A core material which is arranged in the crawler body at intervals in the circumferential direction of the crawler and is made of a material harder than the elastic body is included.
The core material includes a core material body extending in the crawler width direction, and a plurality of derailment prevention protrusions protruding from the first end surface and the second end surface of the core material body in the crawler circumferential direction.
At least one groove extending in the circumferential direction of the crawler is formed in each of the derailment prevention protrusions.
Elastic crawler. The derailment prevention protrusions can enter between a pair of first protrusions protruding from the first end surface and a pair of first protrusions of the core material protruding from the second end surface and adjacent to each other in the crawler circumferential direction. Including a pair of second protrusions
The first surface of the first protrusion on the inner side in the crawler width direction is arranged so as to face the second surface on the outer side in the crawler width direction of the second protrusion of the core material adjacent to the crawler circumferential direction.
The elastic crawler according to claim 1, wherein the groove includes a first groove formed on the first surface and a second groove formed on the second surface. When an external force that twists the pair of core materials adjacent to each other in the circumferential direction of the crawler acts on the crawler body,
The first groove portion meshes with a portion of the second surface facing the second surface that is not the second groove portion.
The elastic crawler according to claim 2, wherein the second groove portion meshes with a portion of the first surface facing the first surface that is not the first groove portion. Further including a tension body composed of a cord arranged in the crawler body and extending in the crawler circumferential direction through the crawler outer peripheral side with respect to the core material.
The elastic crawler according to any one of claims 1 to 3, wherein the portion of the derailment prevention protrusion on the outer peripheral side of the crawler is located on the outer peripheral side of the crawler with respect to the tension body. A core material used for elastic crawlers
The core material body extending in the crawler width direction and
The core material body includes a plurality of derailment prevention protrusions protruding from the first end surface and the second end surface in the crawler circumferential direction, respectively.
At least one groove extending in the circumferential direction of the crawler is formed in each of the derailment prevention protrusions.
Core material. The derailment prevention protrusions can enter between the pair of first protrusions protruding from the first end surface and the pair of first protrusions protruding from the second end surface and arranged in the circumferential direction of the crawler. Including a pair of second protrusions
The fifth aspect of claim 5, wherein the groove includes a first groove formed inside the crawler width direction of the first protrusion and a second groove formed outside the crawler width direction of the second protrusion. Core material. The core material according to claim 6, wherein the first groove portion and the second groove portion have the same cross-sectional shape. The core material according to any one of claims 5 to 7, wherein one groove portion is formed in each of the derailment prevention protrusions. The core material according to any one of claims 5 to 7, wherein a plurality of the groove portions are formed in each of the derailment prevention protrusions. The core material according to any one of claims 5 to 9, wherein the outer end portion of the derailment prevention protrusion on the outer peripheral side of the crawler is located on the outer peripheral side of the crawler with respect to the outer surface of the outer peripheral side of the crawler of the core material main body.

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