JP2006142929A - Rubber crawler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To avoid the concentration of distortion by providing an elevation part as a countermeasure for the bend of an ear of a rubber crawler, and to thereby suppress the generation of ear cutting. <P>SOLUTION: In the rubber crawler, a steel cord row 2 is buried in a rubber elastic body 1 constituting the rubber crawler. The rubber crawler comprises a rubber projection 3 formed on an inner peripheral side and a lug formed on an outer peripheral side. The inner surface of the rubber crawler corresponding to left and right ends of a member contacted with the inner peripheral surface of the rubber crawler is elevated. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber track, particularly a rubber track aimed at preventing an ear-cut of a core bar-less track.

  Hereinafter, the present invention will be described with a coreless rubber crawler as a representative, but the coreless crawler is wound between a sprocket and an idler, and the track roller rolls on the inner peripheral surface. ing. That is, the inner peripheral surface of the rubber crawler rolls while contacting with each other. Since tension is applied to the rubber crawler, the phenomenon that the end portion (ear part) in the width direction of the rubber crawler bends inward at the site where the rubber crawler contacts is repeated. On the other hand, when the rubber track side comes into contact with a curb or the like on the road surface that is running, the width direction end portion (ear portion) of the rubber track is bent.

  FIG. 1 is a cross-sectional view showing this state, in which a steel cord row 2 is embedded in a rubber elastic body 1 constituting a rubber track, and a bias code row is normally embedded inside and outside this, although not shown. Has been. A rubber protrusion 3 is formed on the inner peripheral side of the rubber crawler and serves to transmit a propulsive force by engaging with the sprocket. Reference numeral 4 denotes a lug formed on the outer peripheral side of the rubber crawler, and reference numeral 10 denotes a track roller which is a representative member in contact with the inner peripheral side of the rubber crawler.

  The rubber crawler generates these movements at the same time. In particular, when the bent portions of the ear portions coincide with each other, there are cases where the ear portions are cracked or the ear portions are cut. In the figure, the dotted line indicates the state where the ear part 5 is bent inward, but the ear part 5 of the rubber crawler repeats this, in particular, the member 6 that contacts the inner peripheral side of the rubber crawler. A large distortion is caused in the portion in contact with the left and right outer ends (6a), and a crack C is generated here.

  The present invention provides a rubber crawler for the purpose of preventing damage to the ear part of a rubber crawler, particularly a coreless rubber crawler.

  The gist of the present invention is a rubber crawler having a steel cord row embedded in a rubber elastic body constituting a rubber crawler and comprising a rubber protrusion formed on the inner peripheral side and a lug formed on the outer peripheral side. A rubber crawler is characterized in that the inner surface of the rubber crawler corresponding to the left and right ends of the member contacting the inner peripheral surface of the rubber crawler is raised.

  The present invention is as described above, and it is possible to avoid the concentration of distortion by the raised portion with respect to the bending of the ear portion, thereby suppressing the occurrence of the ear cut, and the life of the rubber crawler is reduced. Improvements are possible.

  The rubber crawler is wound between the sprocket and the idler, and the track roller rolls on the inner peripheral surface. That is, the inner peripheral surface of the rubber crawler is repeatedly contacted and rolled by these members, and the boundary with the non-rolling portion is repeatedly bent, and this portion is raised to prevent the ear from being cut off. Part.

  Although the load of the fuselage is applied outward at the contact portion of each member, the ear portion of the non-contact portion is usually bent inward, so that movement in the opposite direction is added at this boundary. Accordingly, strain concentrates on such a portion, and cracks and the like are generated here. The present invention aims to prevent the occurrence of cracks, and intends to reduce the occurrence of cracks by interposing a raised portion.

  The presence of the raised portion is preferably a belt-like one continuous in the longitudinal direction, but depending on the case, it is interspersed between lugs formed on the outer peripheral side or protrusions formed on the inner peripheral side. The raised portion is formed by forming a depression on the surface of the mold that defines the inner peripheral side when the rubber crawler is molded. The raised portion can be made of high hardness rubber, and the rubber hardness is 75 to 95 degrees (JIS A).

  Hereinafter, the present invention will be described in more detail with reference to examples. FIG. 2 is a perspective view of the rubber crawler (no core metal) of the present invention, and FIG. 3 is a cross-sectional view in the width direction. In FIG. 2, the right half is a first example, and the left half is a second example. A steel crawler 2 is embedded in a rubber elastic body 1 constituting a rubber crawler, and includes a rubber protrusion 3 formed on the inner peripheral side and a lug 4 formed on the outer peripheral side. Reference numeral 5 denotes an ear portion, which is a raised portion on the inner surface of the rubber crawler corresponding to the left and right ends of a member 6 (represented by a track roller here) that contacts the inner peripheral surface of the rubber crawler. 7 is present.

  In particular, as can be seen in FIG. 3, the members 6 such as sprockets, idlers, track rollers and the like roll on the inner peripheral surface of the rubber crawler. The end 6a is at substantially the same position. For this reason, the bending position in each member 6 is substantially the same position, and therefore, the occurrence of cracks in the ear portion 5 is remarkably brought about. In the first example of FIG. 2, the present invention is provided with a belt-like shape continuously in the longitudinal direction of the rubber crawler. The second example of FIG. In this case, the projections 3 and 3 formed on the inner peripheral side are interspersed.

  As for the first example, a groove is formed at a predetermined position on the surface of a mold (not shown) that divides the inner peripheral surface when the rubber crawler is molded, and each material inherent to the rubber crawler. Are vulcanized and molded. That is, an unvulcanized rubber layer that forms the inner peripheral side of the rubber track, an unvulcanized rubber block that forms protrusions, a steel cord row coated with an unvulcanized rubber sheet, and a rubber track The unvulcanized rubber layer that forms the outer peripheral side of the rubber and the unvulcanized rubber layer that forms the lug are placed in the mold, respectively, and this is pressed under the mold that defines the outer peripheral side of the rubber crawler. And the whole unvulcanized rubber is vulcanized to obtain a rubber crawler.

  In addition, about 2-5 mm is enough for the height of the protruding part 7, and the width | variety is enough if it exists in the range which the right-and-left outer edge part 6a of each member 6 enters. If the height and width of the raised portion 7 are more than necessary, there is a drawback that bending resistance increases, leading to energy loss. Therefore, the thickness and width should not be increased abnormally. In this example, the rubber hardness of the raised portion 7 was 90 degrees (JIS A).

  The present invention is as described above, and it is needless to say that the present invention can be applied not only to improving the inner peripheral surface of the core bar-less crawler, but also to rubber crawlers in which the core bar is embedded at regular intervals.

FIG. 1 is a cross-sectional view of a conventional rubber track. FIG. 2 is a perspective view of the rubber track of the present invention. FIG. 3 is a cross-sectional view of the rubber track of the present invention.

Explanation of symbols

1. Rubber elastic body,
2. Steel code train,
3. Rubber protrusion,
4 ... Rug,
5. The ear,
6. A member that rolls on the inner periphery of the rubber crawler
6a ... the outer end of a member that rolls on the inner peripheral side of the rubber track,
7.
10. Track roller,
C: Crack.

Claims (5)

  A rubber crawler comprising a rubber cord embedded in a rubber elastic body constituting a rubber crawler and comprising rubber protrusions formed on an inner peripheral side and lugs formed on an outer peripheral side. A rubber crawler characterized in that the inner surface of the rubber crawler corresponding to the left and right ends of the member that contacts the inner peripheral surface of the member is raised.   2. The rubber crawler according to claim 1, wherein the raised portion is endless in the longitudinal direction of the rubber elastic body.   2. A rubber crawler according to claim 1, wherein the raised portions are formed between lugs of the rubber elastic body.   2. The rubber crawler according to claim 1, wherein the raised portions are formed between the protrusions of the rubber elastic body.   The rubber crawler according to any one of claims 1 to 5, wherein the rubber crawler is a coreless rubber crawler.

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