JPH07137670A - Core bar for rubber crawler - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a crack in rubber and to improve the endurance ability of a rubber crawler by providing a recesses to make the width of a blade part near the lower part of the root of a projection part narrower than the width of blade parts on both the outsides of the projection part. CONSTITUTION:A sprocket engaging part 12 is provided at the center of a core bar 10, and a pair of projection parts 13, 14 which serve as a running face during the passing of rolling wheels or has a preventing function to the falling of rolling wheels is provided on both the outsides of the engaging part, and moreover blade parts 15, 15 extending right and left are provided on both the outsides of the projection parts 13, 14. and the above parts 12 to 15 are united to form a core bar for a rubber crawler, and the core bar has recesses 161, 161 provided so as to make the width of blade parts 16, 16 near the lower part of the root of the projections of the projection parts 13, 14 narrower than the width of the blade parts 15, 15 on both the outsides of the projection part. When a rubber crawler is wound on the sprocket or an idler and repeatedly bent, stress occurring between adjacent core bars to the rubber is about equal and can be dispersed without concentration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a core bar for a rubber crawler, and more particularly, when the rubber crawler is repeatedly bent, the bending of the rubber near the blades near the base of the protrusions of the adjacent cores. The present invention relates to a core bar for a rubber crawler, which has improved durability against fatigue.

[0002]

2. Description of the Related Art Conventionally, in a core bar for a rubber crawler, the width of the blade portion near the base of the protrusion and the width of the blade portion extending to both outsides of the protrusion are the same. For this reason, when repeatedly used as a rubber crawler, the adhesion thickness of the rubber on the blades near the base of the protrusion between the adjacent cores differs depending on the front and back of the core, and stress on the rubber in this vicinity The degree of concentration was different, which caused the occurrence of rubber cracks.

FIG. 5 is a plan view of a conventional cored bar embedded in a rubber crawler, and FIG. 6 is a bottom view of the conventional cored bar shown in FIG. 5, near the bottom of the protrusion of the cored bar. The width of the blade portion and the width of the blade portion extending to both outsides of the protrusion are the same. Figure 7
FIG. 6 is a rubber crawler manufactured using the core bar shown in FIG. 5, and is a cross-sectional view of the core bar shown in FIG. 5 taken along the line BB. FIG. 8 is a sectional view showing a state of bending when the rubber crawler of FIG. 7 is wound around a sprocket or an idler. Since the adhesion thickness of the rubbers 23, 24 on the blades near the roots of the protrusions between the adjacent cores is different, the degree of concentration of stress on the rubber in the vicinity is different, which causes the occurrence of rubber cracks.

[0004]

SUMMARY OF THE INVENTION According to the present invention, when a rubber crawler is bent around a sprocket or an idler, it is bent between adjacent cores near the blades under the protrusions of the core. The generated rubber stress is almost even, and the stress is dispersed without being concentrated, preventing the rubber from cracking in the vicinity of the blade under the protrusion of the core metal and improving the durability of the rubber crawler. The purpose is to do.

[0005]

The present invention is based on the knowledge that the movement of a cored bar embedded in a rubber crawler is scrutinized in order to solve the above problems. That is, the present invention is
A sprocket engaging portion is provided in the central portion, protrusions are provided on both outer sides of the engaging portion, and blades are provided on both outer sides of the protruding portion, so that the core of the rubber crawler is integrally formed. A rubber crawler core bar, characterized in that recesses are provided such that the width of the blades near the bottom is narrower than the width of the blades on both outer sides of the protrusion.

Of course, the present invention can also be applied to a cored bar having rails for passing rolling wheels longer than the blades on both outer sides of the protrusion.

[0007]

By adopting the above-mentioned structure, when the rubber crawler is bent around the sprocket or the idler, it is generated between the adjacent cores near the blade under the protrusion of the core. By making the stress on the rubber almost even and distributing it without concentrating the stress, it is possible to prevent the rubber from cracking in the vicinity of the blade under the protrusion of the core metal.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a front view showing an embodiment of a cored bar embedded in a rubber crawler of the present invention, and FIG. 2 is a bottom view thereof. In the figure, a core metal 10 is provided with a sprocket engaging portion 12 in the center thereof, and a pair of protrusions having a sprocket engaging portion 12 on both outer sides of the engaging portion, which serve as a running surface when a rolling wheel passes, or which has a function of preventing the rolling wheel from coming off. A core bar for a rubber crawler, which includes 13 and 14, and further has vane portions 15 and 15 extending to the left and right on both outer sides thereof to be integrated.

However, in the cored bar 10 of this embodiment, the blade portions 16 and 16 near the bases of the protrusions 13 and 14 are located below the bases of the protrusions.
Is a core metal for a rubber crawler in which concave portions 161 and 161 are provided so that the width of the concave portion is narrower than the width of the blade portions 15 and 15 on both outer sides of the protruding portion.

FIG. 3 is a cross-sectional view of a rubber crawler manufactured by using the cored bar shown in FIG. 1, which is taken along the line AA of the cored bar of FIG. Wing 1 near the bottom of the protrusion
The widths of 6 and 16 are narrow, and the adhesion thicknesses of the rubbers 21 and 22 before and after the blade portion near the base of the protrusion are substantially the same.

FIG. 4 is a cross-sectional view showing a state in which the rubber crawler of FIG. 3 is bent when it is wound around a sprocket or an idler. Since the rubber adhesion thicknesses 21 and 22 of the blades near the bases of the protrusions between the adjacent cores are almost equal, the concentration of stress on the rubber near the bases of the protrusions between the adjacent cores is almost equal. The structure is such that the stress can be dispersed without being concentrated.

[0012]

According to the present invention, because of the above-described structure, when the rubber crawler is wound around a sprocket or an idler and repeatedly bent, the stress applied to the rubber between the adjacent cores is It is almost even and can be dispersed without being concentrated, and it is possible to prevent the rubber from cracking in the vicinity of the blade portion under the core of the metal core and to improve the durability of the rubber crawler.

[0013]

[Brief description of drawings]

FIG. 1 is a plan view of a cored bar embedded in a rubber crawler of the present invention.

FIG. 2 is a bottom view of the cored bar shown in FIG. 1 of the present invention.

FIG. 3 is a cross-sectional view of a rubber crawler manufactured by using the cored bar shown in FIG. 1 of the present invention, which is taken along the line AA of the cored bar shown in FIG.

FIG. 4 is a cross-sectional view when the rubber crawler shown in FIG. 3 of the present invention is bent.

FIG. 5 is a plan view of a cored bar embedded in a conventional rubber crawler.

FIG. 6 is a bottom view of the conventional cored bar shown in FIG.

FIG. 7 is a cross-sectional view of a rubber crawler manufactured using the cored bar shown in FIG. 5, which is taken along the line BB of the cored bar shown in FIG.

FIG. 8 is a cross-sectional view when the rubber crawler shown in FIG. 5 is bent.

[Explanation of symbols]

10 ・ ・ ・ ・ Core metal 12 ・ ・ ・ Sprocket engaging part 13, 14 ・ ・ ・ Projection part 15 ・ ・ ・ ・ Vane part 16 ・ ・ ・ Protrusion part Blade portion 161..Recessed portion of blade portion 20 ..... Rubber on tread surface portion of rubber crawler 21,22 ..... Rubber near the base of the protrusion between adjacent cores 23,24 .. ..Conventional rubber in the vicinity of the base of the protrusion between adjacent cores 25 ..... Rubber groove between adjacent cores

Claims (1)

[Claims] 1. A mandrel for a rubber crawler, comprising a sprocket engaging portion provided at a central portion, projections provided on both outer sides of the engaging portion, and blades provided on both outer sides of the projection. 2. A core bar for a rubber crawler, characterized in that a recess is provided such that the width of the blade portion near the bottom of the protrusion is narrower than the width of the blade portions on both outer sides of the protrusion.