JP2001010556A - Rubber crawler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber crawler for arranging a bias cord for suppressing the generation of twisting and improving lateral rigidity without causing weight increase or winding rigidity to a roller. SOLUTION: In an endless belt-like rubber crawler 1 embedded with a main cord 4 having a cord angle in a peripheral direction, a single layer bias cord, constituted by combining plural cords 5 and 6 having a reverse cord angle with each other in a same plane, is laminated on the cord 4. In a bias cord, twist shearing force between plural cords for constituting the bias cord is effectively canceled, while having light weight and simple structure being sufficient as one layer in the same plane, to improve straightly-advancing travel performance, and moreover since the cords 5 and 6 have a single layer, weight increase of the whole roller 1 is not caused and winding rigidity to driving and driven rollers is low, to eliminate the increase of travel resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber track, and more particularly to a coreless rubber track having a main cord and a bias cord embedded therein.

[0002]

2. Description of the Related Art Generally, a coreless rubber crawler includes a main cord having a circumferential cord angle in an endless belt-shaped rubber body, and a bias cord for reinforcing the cord by improving torsional rigidity and lateral rigidity. Is buried. As shown in FIGS. 6A and 6C, in this type of rubber crawler 21, a main cord 24 having a circumferential cord angle is embedded on a substantially center line in a thickness direction in an endless rubber body. A bias cord 25 having opposite cord angles (typically 45 °, see FIG. 6B) to reinforce it by improving torsional rigidity and lateral rigidity;
26 are sequentially laid and buried on the ground side (the upper side in FIG. 6C). However, as shown in FIG. 6 (A), when the rubber crawler 21 is wound around the driving roller 10 (or the driven roller), a tensile force acts on the outer peripheral side of the center line, and the inner side of the center line is normally actuated. A compressive force acts on the circumferential side. Moreover, the magnitude of these forces increases as the distance from the center line increases. Therefore, as described above, when a pair of bias cords 25 and 26 having code angles opposite to each other at substantially the same angle are stacked, a larger pulling force is applied to the bias cord 26 on the outer peripheral side which is the ground side. The force T acts, and a torsional force F, which is a shearing force due to the cord angle of the bias cord 26, is generated as shown in FIG. Therefore, the rubber crawler is twisted by the difference in the shearing force generated due to the difference in the inner and outer peripheral positions due to the lamination of the bias cords, and the straight running performance is deteriorated.

Therefore, Japanese Patent Publication No. 7-4184 shown in FIG.
No. 8 has proposed an endless belt.
This is because a first ply 72 having a cord angle in the circumferential direction is provided in the belt body 49, and a 45 °
, And a third ply 76 having a cord angle of minus 60 °, which is laminated on the outer peripheral side thereof, is embedded. Reference numeral 78 denotes an orthogonal code (which is orthogonal to the code of the first ply 72) stacked further on the outer peripheral side of the third ply 76.
With this configuration, the cord angle of the third ply 76 laminated on the outer peripheral side is minus 60 ° with respect to the cord angle of 45 ° in the second ply 74 where the maximum torsional force is normally generated. Thus, the torsional force due to the large tensile force generated in the third ply 76 due to the lamination on the outer peripheral side is intended to be reduced.

[0004]

However, an attempt has been made to reduce the torsional force due to the tensile force between a plurality of bias cords laminated and disposed on the inner and outer peripheries by making the cord angles different from each other. As a result, the torsion of the rubber crawler is reduced and the straight running performance is improved, but the minimum weight of the two layers of the second and third plies on the inner and outer peripheries increases the weight of the entire rubber crawler. In addition, the rigidity of the rubber crawler around the driving roller and the driven roller is increased, and the running resistance is increased.

Accordingly, the present invention solves the above-mentioned problems of the conventional rubber track and arranges a bias cord capable of suppressing the occurrence of torsion and improving the lateral rigidity without increasing the weight or rigidity of winding around the roller. It is an object of the present invention to provide a rubber crawler that can be installed.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention provides an endless belt-type rubber crawler in which a main cord having a circumferential cord angle is embedded, the plurality of cords having cord angles opposite to each other in the same plane. And a single layer of bias code constituted by combining the above codes is laminated on the main code. Further, the present invention is characterized in that the bias code is composed of two codes having substantially the same width. Further, the present invention is characterized in that the bias codes are configured by alternately arranging even numbers of codes having code angles opposite to each other. Further, according to the present invention, among a plurality of codes constituting the bias code, a total of widths of codes having a predetermined code angle and a total of widths of codes having a code angle opposite to the predetermined code angle are equal. It is characterized by having done. Further, the present invention is characterized in that another cord is arranged on the outer peripheral side of the butting portion of the adjacent cords having the opposite cord angles. Further, the present invention is characterized in that edges of one cord are overlapped at abutting portions of adjacent cords having the opposite cord angles, and these are arranged to solve the problem. It is assumed that.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a view showing a rubber crawler according to a first embodiment of the present invention. FIG. 1 (A) is a cross-sectional view of the rubber crawler, and FIG. 1 (B) is a view taken in the direction of arrow A in FIG. 1 (A). . FIG.
As shown in FIG. 1A, a rubber crawler 1 of the present invention has a large number of guide projections 2 of rolling wheels at predetermined intervals in a circumferential direction along a center on an inner circumferential side (upward in the drawing). The main cord 1 and the bias cords 5 and 6 are buried in a rubber body which is provided with a large number of ground lugs 3 inclined in the transverse direction at the ground contact portion on the side at a predetermined interval in the circumferential direction. The present invention is characterized in that a single-layer bias code formed by combining a plurality of codes having mutually opposite code angles in the same plane is laminated on the main code. As shown in FIG. 1B, which is a view taken in the direction of arrow A in FIG. 1A, the main cord 4 buried substantially on the center line in the thickness direction of the rubber crawler 1 has a circumferential cord angle. The first bias cord 5 and the second bias cord 6 stacked on the ground side of the main cord 4 have mutually opposite cord angles in the same plane, and have the width W1 of one bias cord 5 and The width W2 of the other bias code 6 is configured to be equal. If the cord angle of one of the bias cords is such that only a small torsional shear force is generated, the width of the bias cord may be widened to offset the generation of the torsional force as a whole crawler. .

FIG. 2 is a view showing a second embodiment of the rubber crawler of the present invention. In this embodiment, a single-layer bias cord is formed in the same plane where the main cord 4 is laminated. Codes 5A, 5B, 6A and 6B having code angles opposite to each other
Are alternately arranged side by side. With this configuration, the torsional force generated by the bias cord angle between the adjacent cords 5A and 5B having opposite cord angles and between the cords 6A and 6B is offset. Twisting of the entire crawler is effectively suppressed. Here, the cord angles between adjacent ones of the cords 5A to 6B are substantially equal in opposite directions, and their widths are also substantially equal.

FIG. 3 is a view showing a third embodiment of the rubber crawler of the present invention. In this embodiment, a single-layer bias cord is formed in the same plane where the main cord 4 is laminated. Each of the cords is characterized in that another pressing cord 7 is disposed on the outer peripheral side of the butting portion of the adjacent cords 5 and 6 having the opposite cord angles. The other holding cord 7 has a relatively small width, a cord angle orthogonal to the circumferential cord angle of the main cord 4, and does not affect the generation of torsional shear force. . The holding cord according to the present embodiment can be used as a butting portion between adjacent cords of the other embodiments of the present invention. With this configuration, it is possible to firmly hold the abutting portion between the cords when the rubber crawler 1 is wound around the driving roller or the driven roller or when the rubber crawler 1 is buffered by the rolling wheel.

FIG. 4 is a view showing a rubber crawler according to a fourth embodiment of the present invention. In this embodiment, a single-layer bias cord is formed in the same plane where the main cord 4 is laminated. In the abutting portion of the adjacent cords 5 and 6 having the opposite cord angles, the edge of one cord (the first bias cord 5 in the illustrated example) overlaps the other cord. Thus, the overlap portion 8 is formed. With this configuration, in the present embodiment, one of the cords can be extended to function as a holding cord without separately arranging a special member, and the butting portion between the cords can be reliably formed. Can be held. The extended portion formed by extension of this embodiment can also be used as a butted portion between adjacent cords of another embodiment of the present invention.

FIG. 5 is a view showing a fifth embodiment of the rubber track according to the present invention. In this embodiment, a single-layer bias cord is formed in the same plane where the main cord 4 is laminated. The code having a total width W3 of the width of the code 9 having a predetermined code angle and a code having a code angle opposite to the predetermined code angle among a plurality of codes 5, 6, 9 constituting the bias code. 5,6
Are made equal to the total width W4 + W5. Therefore, according to the present embodiment, a single wide cord 9 having a predetermined bias angle and a cord 5 having a half width of the cord 9 and a reverse cord angle, 6 and 6. With such a configuration, various combinations of cords can be made by selecting the cord angle and width, and the degree of freedom in design is improved.

Although the embodiments of the present invention have been described in detail above, the shape of the rubber crawler and the shape of the rubber crawlers are within the scope of the present invention.
Type, main and bias cord type (not to mention rubberization, the cord may be directly embedded in the rubber crawler body, and the cord material may be steel,
Appropriate materials such as organic fibers can be employed. ), The cord angle, the arrangement of the holding cords, the formation of the overlap portion, the width of each cord constituting the bias cord (in the embodiments shown in FIGS. 1 to 5, the cord of each cord constituting the bias cord) Although the angle has been described as being limited to a predetermined angle and a code angle opposite thereto, as long as each code constitutes a single-layer bias code in the same plane,
It is within the scope of the present invention that the width of the cords to be combined is appropriately selected and combined so as not to generate a torsional shearing force as a whole crawler depending on the selection of different cord angles of the cords. ) Etc. can be appropriately selected.

[0013]

As described above in detail, according to the present invention, in the endless belt-like rubber track in which the main cord having the circumferential cord angle is buried, the cord angles opposite to each other in the same plane. By laminating a single-layer bias cord composed of a combination of a plurality of cords having the above-mentioned configuration on the main cord, the bias cords laminated and disposed on the main cord for securing lateral rigidity or the like are in the same plane. Although it is a lightweight and simple structure that requires only one layer, the torsional shear force between a plurality of cords constituting the same effectively cancels out the tension when the rubber crawler is wound around the drive roller and the driven roller. As a result, no torsional force was generated, and the straight running performance was improved. In addition, since the bias cord has a single layer, the weight of the entire rubber crawler does not increase, the winding rigidity around the driving roller and the driven roller is low, and the running resistance does not increase. Further, the bias code is
In the case of two cords having substantially the same width, a pair of bias cords may be arranged symmetrically, so that the production is simplified and the action of suppressing the generation of torsional force is relatively stable. .

Further, when the bias cords are constituted by alternately arranging an even number of cords having cord angles opposite to each other, it is possible to arrange a large number of cords having a relatively narrow width, thereby increasing the yield. The degree of freedom is improved. Furthermore, when the sum of the widths of the cords having a predetermined code angle and the sum of the widths of the cords having a code angle opposite to the predetermined code angle are made equal among a plurality of codes constituting the bias code. Various combinations of cords are possible by selecting the cord angle and width, and the degree of freedom of design is improved. In the case where another cord is disposed on the outer peripheral side of the butting portion of the adjacent cords having the opposite cord angles, when the rubber crawler is wound around the driving roller or the driven roller, or when the roller is used. At the time of buffering, the butting portion between the cords can be firmly held.

Further, when the edges of one cord are overlapped at the abutting portion of the adjacent cords with the cord angles opposite to each other, no extra member is separately provided, and Can be extended to function as a presser cord, and the butting portion between the cords can be reliably held. Thus, according to the present invention, there is provided a rubber crawler capable of disposing a bias cord capable of suppressing the occurrence of torsion and improving the lateral rigidity without increasing the weight or rigidity of winding around the roller.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a rubber track according to the present invention, and FIG. 1 (A) is a cross-sectional view of the rubber track;
FIG. 2B is a bottom view of a main part as viewed from the direction of arrow A in FIG.

FIG. 2 is a bottom view of a main part of a rubber track according to a second embodiment of the present invention.

FIG. 3 is a bottom view of a main part of a rubber track according to a third embodiment of the present invention.

FIG. 4 is a bottom view of a main part of a rubber track according to a fourth embodiment of the present invention.

FIG. 5 is a bottom view of a main part of a rubber track according to a fifth embodiment of the present invention.

FIG. 6 is a diagram illustrating one conventional example of a rubber track and its behavior.

FIG. 7 is a perspective view of a main part of another conventional rubber track.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rubber crawler 2 Guide protrusion 3 Ground lug 4 Main cord 5 First bias cord 6 Second bias cord 7 Pressing cord 8 Overlap part 9 Third bias cord

Claims (6)

[Claims] An endless belt-shaped rubber track in which a main cord having a cord angle in a circumferential direction is embedded.
A rubber crawler, wherein a single layer of bias cords formed by combining a plurality of cords having opposite cord angles in the same plane is laminated on the main cord. 2. The rubber crawler according to claim 1, wherein the bias cord comprises two cords having substantially the same width. 3. The rubber track according to claim 1, wherein the bias cords are constituted by alternately arranging an even number of cords having mutually opposite cord angles. 4. A plurality of codes constituting the bias code, wherein a sum of widths of cords having a predetermined code angle is equal to a sum of widths of codes having a code angle opposite to the predetermined code angle. The rubber crawler according to claim 3, wherein: 5. The rubber according to claim 1, wherein another cord is disposed on an outer peripheral side of a butt portion of the adjacent cords having the opposite cord angles. Crawler. 6. The cord according to claim 1, wherein an edge of one cord is overlapped at an abutting portion of the adjacent cords with the cords having opposite directions. Rubber track.