JP2008149770A - Core for elastic crawler and elastic crawler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce selvage cutting of a crawler body in a core used for an elastic crawler and the elastic crawler using the core. <P>SOLUTION: The core 8 for the elastic crawler has a wing part 9 embedded in the crawler body 7 of the elastic crawler and a projection part 10 projected from an upper surface 9a of the wing part 9 and formed. At least one corner part 12 of the end part of longitudinal direction G of the wing part 9 is formed upward in a folded shape, the back surface 12b of the corner part 12 is formed by being inclined at an angle of 10°or more and 60° or less with respect to the back surface 12b of the corner part 12, and a boundary line 12 between the back surface 12b of the corner part 12 and the bottom surface 9b of the wing part 9 is formed by being inclined at the angle of 30°or more and 70° or less with respect to the longitudinal direction G of the wing part 9. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a core bar used for an elastic crawler belt and an elastic crawler belt using the core bar.

The elastic crawler belt (elastic crawler) is used for a traveling device of a construction machine or an agricultural machine, for example. This elastic crawler belt is formed in an endless belt shape with a rubber material or the like, and a plurality of lugs are formed on the outer peripheral surface thereof to exert traction force. Inside the elastic crawler belt, an endless tensile body made of a steel cord and a core metal for reinforcement are embedded (for example, see Patent Document 1).
The metal core includes a wing portion embedded in an elastic crawler belt formed of rubber or the like, and a protrusion protruding from the wing portion. The end portion of the wing portion is formed in a tapered shape as it goes outward in the longitudinal direction of the cored bar.
JP 2006-69292 A JP 2006-151140 A

In the conventional elastic crawler belt, the end of the metal core protrudes in a tapering shape in the width direction of the crawler belt main body, so that the end of the lug in the width direction rides on the curb or the like and is rubbed against the wall surface. In some cases, stress concentrates on the end of the core metal, and a crack (hereinafter referred to as “ear cut”) may occur in the end of the crawler belt body in the width direction. In particular, when the end in the width direction of the crawler belt body comes into contact with the curbstone or the wall surface at an angle and is rubbed while rotating, ear cuts occur early.
This invention is made | formed in view of such a situation, and it aims at providing the core metal for elastic crawler belts which can reduce the ear-cut of a crawler belt main body.

  Moreover, an object of this invention is to provide the elastic crawler track which can reduce the ear-cut of a crawler belt main body.

In order to solve the above problems, the present invention has taken the following technical means.
That is, an elastic crawler metal core according to the present invention is an elastic crawler metal core having a wing portion embedded in the crawler belt main body of the elastic crawler belt and a protrusion protruding from the upper surface of the wing portion. At least one corner portion of the end portion is bent upward, and the back surface of the corner portion is formed to be inclined at an angle of 10 ° to 60 ° with respect to the bottom surface of the wing portion. The boundary line between the back surface of the wing portion and the bottom surface of the wing portion is formed to be inclined at an angle of 30 ° or more and 70 ° or less with respect to the longitudinal direction of the wing portion.

In this way, the corner of the wing portion in the width direction is bent upward and the back surface of the corner is inclined at a predetermined angle with respect to the bottom surface of the wing. The back surface of the corner portion faces upward in the grounding direction of the crawler belt body when embedded in the crawler belt body. Thereby, even when the end portion in the width direction of the crawler belt main body is rubbed against the curbstone or the wall, the stress concentration on the corner portion is reduced. Thereby, it becomes possible to reduce the ear-cut of the crawler belt main body.
Further, the core for elastic crawler belt according to the present invention is characterized in that a chamfer is applied to a boundary portion between the bottom surface of the wing portion and the back surface of the corner portion.

According to this, the stress concentration on the boundary portion between the bottom surface of the wing portion and the back surface of the corner portion of the cored bar is reduced, thereby improving the cut resistance of the elastic crawler belt.
Moreover, the elastic crawler belt according to the present invention is characterized in that the core metal is embedded in the crawler belt main body, and a corner portion on the rear side of the core metal is formed in a bent shape upward.
According to this, even when the elastic crawler belt reverses, the end of the elastic crawler belt in the width direction comes into contact with the curbstone or the wall surface and is rubbed upward, thereby reducing the stress concentration on the corner. As a result, it is possible to reduce the cutting of the crawler belt body.

Further, in the elastic crawler belt according to the present invention, a plurality of lugs are formed along the circumferential direction of the crawler belt main body on the outer peripheral surface of the crawler belt main body, and the lug is a portion on the center side in the width direction of the crawler belt main body. Further, the crawler belt main body is formed in an inclined shape so that a portion on the end side in the width direction is located rearward.
When this elastic crawler belt is moved backward and the end in the width direction is rubbed upward with the curbstone or wall surface in contact with the elastic crawler belt, stress concentration on the corner portion can be reduced, and the cuff body can be cut off.

  According to the present invention, it is possible to reduce the ear cut of the crawler belt main body.

The best mode for carrying out the present invention will be described below with reference to the drawings.
1 to 6 show an embodiment of an elastic crawler belt 1 and an elastic crawler metal core 8 (hereinafter simply referred to as “core metal 8”) according to the present invention.
An elastic crawler belt 1 according to the present invention is attached to a traveling device 2 of a work machine such as a construction machine or an agricultural machine. For example, the traveling device 2 is configured such that wheels such as a sprocket 4, an idler 5, and a plurality of wheels 6 are rotatably provided on a track frame 3. The elastic crawler belt 1 is wound around each wheel of the traveling device 2 and is driven by the sprocket 4 to travel.

As shown in FIGS. 5 and 6, the elastic crawler belt 1 is moved in the direction indicated by the symbol F (hereinafter referred to as the front) so that the work machine moves forward, and the direction indicated by the symbol R (hereinafter referred to as the following). It is mounted on the traveling device 2 so that the work machine moves backward when it turns to the rear.
As shown in FIG. 5, the elastic crawler belt 1 has an endless belt-like crawler belt body 7. The crawler belt body 7 is formed in an endless shape by vulcanizing and molding rubber. Hereinafter, the band longitudinal direction of the crawler belt body 7 is simply referred to as “circumferential direction” (indicated by symbol A in the figure), and the band width direction orthogonal to the circumferential direction A is simply referred to as “width direction” (reference numeral in the figure). B).

  Further, the direction from the end portion 7a in the width direction B of the crawler belt body 7 to the center C (indicated by a one-dot chain line in FIG. 5) in the width direction B of the crawler belt body 7 is referred to as “width direction inward”. The direction from the center C in the width direction B of the crawler belt body 7 toward the end portion 7a in the width direction B of the crawler belt body 7 is referred to as “outward in the width direction”. A plurality of lugs 14 are formed along the circumferential direction A on the outer circumferential surface 7 c of the crawler belt body 7. The plurality of lugs 14 includes a first lug row 14A formed on one side in the width direction B of the crawler belt body 7 and a second lug formed on the other side, with the center C in the width direction B of the crawler belt body 7 as a boundary. The lug row 14B is formed separately. The lugs 14 of the first lug row 14A and the lugs 14 of the second lug row 14B are formed to be staggered (staggered).

As shown in FIG. 5, each lug 14 is formed to be inclined at a predetermined angle with respect to the circumferential direction A of the crawler belt body 7 in a plan view. Each lug 14 is formed in an inclined shape so as to gradually move backward as it goes outward from the center C side in the width direction B of the crawler belt body 7.
Therefore, each lug 14 has a portion 14b on the width direction end portion 7a side of the crawler belt body 7 located behind the portion 14a on the center C side in the width direction B of the crawler belt body 7.
A plurality of holes 15 into which the teeth of the sprocket 4 of the traveling device 2 are fitted are formed at the center C in the width direction B of the crawler belt body 7. Each hole 15 is formed through the crawler belt body 7. The holes 15 are formed at a predetermined pitch along the circumferential direction A of the crawler belt body 7.

An endless tensile body 13 made of steel cord or the like is embedded in the crawler belt body 7 (not shown).
The cored bar 8 is formed in a substantially rectangular shape in plan view. The metal core 8 includes a wing part 9 embedded in the crawler belt main body 7 of the elastic crawler belt 1 and a protrusion 10 protruding from the upper surface 9 a of the wing part 9. The wing portion 9 has a plate shape, and is provided on one side and the other side in the longitudinal direction of the cored bar 8. The wing portion 9 is embedded in the crawler belt body 7 along the width direction B of the crawler belt body 7.
The wing portion 9 is a flat surface having a bottom surface 9b formed horizontally. The upper surface 9a of the wing portion 9 is formed to be inclined at a predetermined angle with respect to the bottom surface 9b. The upper surface 9 a of the wing part 9 is inclined so as to gradually approach the bottom surface 9 b of the wing part 9 from the center in the longitudinal direction of the cored bar 8 toward the end of the wing part 9. Thereby, each wing | blade part 9 of the metal core 8 is gradually thinned toward the front-end | tip part.

As for the wing | blade part 9 of the metal core 8, the corner | angular part 12 of the edge part of the longitudinal direction (it shows with the code | symbol G in the figure) is formed in the upward bending shape. In this embodiment, two corners 12 in one wing 9 are bent upward. Here, “upward” refers to a direction from the bottom surface 9 b of the wing part 9 toward the upper surface 9 a. Thereby, the surface 12a of the corner | angular part 12 inclines upwards with a predetermined angle with respect to the upper surface 9a of the wing | blade part 9, and is formed.
Between the two corners 12, there is a non-bent portion 16 that is not bent. As shown in FIG. 2, the surface 16 a and the bottom surface 16 b of the non-bent portion 16 are formed so as to be substantially parallel to the bottom surface 9 b of the wing portion 9 in a side view. The tip of the corner 12 is chamfered.

As described above, the corner portion 12 is bent upward, so that the back surface 12b of the corner portion 12 is in the cross-sectional direction perpendicular to the boundary line 21, and the bottom surface 9b (or horizontal direction) of the wing portion 9. Is inclined at a predetermined angle α (see FIG. 3). The inclination angle α is preferably 10 ° or more and 60 ° or less.
A boundary line 21 between the back surface 12b of the corner portion 12 and the bottom surface 9b of the wing portion 9 is inclined at a predetermined angle θ with respect to the longitudinal direction G of the wing portion 9 (longitudinal direction of the cored bar 8) in plan view. It is formed (see FIG. 1). The inclination angle θ is preferably 30 ° or more and 70 ° or less.

A chamfer is applied to a boundary portion 19 between the bottom surface 9b of the wing portion 9 and the back surface 12b of the corner portion 12. Thereby, the bottom face 9b of the wing | blade part 9 and the back surface 12b of the corner | angular part 12 are connected and formed continuously.
Each cored bar 8 is formed with two protrusions 10. Each protrusion 10 is formed on one side and the other side in the longitudinal direction of the cored bar 8 with the central part in the longitudinal direction of the cored bar 8 interposed therebetween. The protrusion 10 protrudes from the crawler belt body 7. The protrusion 10 guides the wheel 6 of the traveling device 2 so that it can rotate at a predetermined position. When the wheel 6 of the traveling device 2 is displaced in the width direction B, the wheel 6 hits the protrusion 10 to prevent wheel removal.

According to the elastic crawler belt 1 and the core metal 8 having the above-described configuration, the corner portion 12 of the wing portion 9 is bent upward, so that the back surface 12b of the corner portion 12 is It is formed facing outward in the width direction.
As a result, when the crawler belt body 7 comes into contact with the curbstone, the wall surface or the like and is rubbed up while the work machine is traveling, the back surface 12b of the corner 12 faces the curbstone or the like. In this case, since the back surface 12b of the corner portion 12 receives stress acting on the crawler belt body 7, stress concentration acting on the corner portion 12 can be alleviated. Thereby, the elastic crawler belt 1 comes to be able to reduce the ear-cut of the crawler belt main body 7.

Further, by chamfering the boundary portion 19 between the back surface 12b of the corner portion 12 of the wing portion 9 and the bottom surface 9b of the wing portion 9, the stress concentration on this portion is also reduced, and the cut-resistance of the crawler belt body 7 is improved. It can be further improved.
When the elastic crawler belt 1 rides on the curb, as shown in FIG. 8, the elastic crawler belt 1 comes into contact with the curb from a state inclined with respect to the wall surface 22 of the curb. Thus, even when the elastic crawler belt 1 rides on a curb or the like from the inclined state, the boundary line 21 between the back surface 12b of the corner portion 12 and the bottom surface 9b of the wing portion 9 is in the longitudinal direction G of the wing portion 9. In contrast, since the back surface 12b of the corner portion 12 is inclined corresponding to this inclination, the back surface 12b is as parallel as possible to the side surface of the curb or the like. Face to face.

Therefore, even when the elastic crawler belt 1 is in contact with the curbstone or the like obliquely as shown in FIG. 8, the stress concentration is relieved by the back surface 12 b of the corner 12 receiving the stress acting on the crawler belt body 7. Thus, ear cuts can be reduced.
FIG. 7 shows another embodiment of the cored bar 8 according to the present invention.
In the embodiment of FIG. 1 to FIG. 6 described above, the two corner portions 12 of each wing portion 9 of the cored bar 8 are formed in a bent shape, but in this embodiment, of the two corner portions 12. One is formed in a bent shape. The metal core 8 is embedded in the crawler belt main body 7 shown in the embodiment of FIGS. 1 to 6 described above. In this case, the cored bar 8 is preferably embedded so that the corner 12 formed in a bent shape is located on the rear side of the corner 12 not formed in a bent shape. The reason for this is that when moving backward, the operator is less likely to notice an obstacle behind the vehicle and may come into contact with a curb or the like to cause a damage accident or the like. When traveling forward, it is easy for the operator to check obstacles ahead, and there is less risk of traveling backwards. In the present invention, the two corners 12 are not limited to be bent upward, but at least one corner 12 in the one wing 9 may be bent upward.

As described above, the lug 14 of the crawler belt main body 7 is configured so that the traction acts greatly when the work machine is moved backward, so that the corner portion 12 formed in a bent shape upward is disposed on the rear side. Thus, even when the crawler belt body 7 is rubbed against the curbstone or the wall surface when the work machine is moved backward, the stress concentration is relieved by the back surface 12b of the corner portion 12 formed in a bent shape, Ear breakage of the crawler belt body 7 can be reduced. The other structure of the cored bar 8 is the same structure as the embodiment of FIGS. 1 to 6 and produces the same function and effect.
The applicant conducted the following test in order to confirm the effect of the present invention.

In the test, Examples 1 to 7 and Comparative Examples 1 to 4 of the elastic crawler 1 according to the present invention were sequentially attached to a traveling device of a hydraulic excavator, and entered at an angle of 15 ° to 20 ° with respect to the curb (see FIG. 8). When the elastic crawler 1 climbs onto the curb, the hydraulic excavator is retracted to return to the original position, and then enters the curb again. When the elastic crawler 1 slips without climbing on the curbstone, it stops once and the traveling device is moved backward to return to the original position.
This process was repeated to examine the number of ear breaks occurring in the lug 14 of the elastic crawler 1.
In addition, when a conventional elastic crawler belt in which the corner portion 12 of the core bar 13 is not bent is prepared and the conventional example is run, the number of ear cuts generated in the lugs is set as an ear cut performance value 100. Indexing was performed, and this value was compared with the ear cutting performance of the example of the elastic crawler 1 according to the present invention and the comparative example. It should be noted that the smaller the number of ear cuts, the larger (better) the value of the ear cut performance.

The test results are shown in Table 1.
In Table 1, “θ” indicates an inclination angle formed by the boundary line 21 between the back surface 12 b of the corner portion 12 and the bottom surface 9 b of the wing portion 9 with respect to the longitudinal direction G of the wing portion 9.
In Table 1, “α” indicates an inclination angle in a cross-sectional direction perpendicular to the boundary line 21 formed by the back surface 12b of the corner portion 12 with respect to the bottom surface 9b of the wing portion 9.

As shown in Table 1, according to this test, Examples 1 to 7 of the elastic crawler belt 1 according to the present invention have better ear-cut performance than the conventional examples and the comparative examples. It was found that ear loss can be reduced more.
By this test, the inclination angle θ formed by the boundary line 21 between the back surface 12b of the corner portion 12 and the bottom surface 9b of the wing portion 9 with respect to the longitudinal direction G of the wing portion 9 (longitudinal direction of the core metal 8) is 30 ° or more and 70. It has been found that when the inclination angle α of the back surface 12b of the corner portion 12 with respect to the bottom surface 9b of the wing portion 9 is 10 ° or more and 60 ° or less, the ear cutting performance is improved.

In addition, as shown in Examples 2 to 4, this test shows that the boundary line 21 between the back surface 12b of the corner portion 12 and the bottom surface 9b of the wing portion 9 is the longitudinal direction G of the wing portion 9 (longitudinal direction of the cored bar 8). It is found that the ear cutting performance is further improved when the inclination angle θ formed with respect to the angle is 45 ° to 70 ° and the inclination angle α of the back surface 12b of the corner portion 12 with respect to the bottom surface 9b of the wing portion 9 is 45 °. .
The present invention is not limited to the above-described embodiment, and various modifications and changes can be made.

  INDUSTRIAL APPLICABILITY The present invention can be used for elastic crawler belts used for agricultural machines and construction machines.

It is a top view of the core metal in one embodiment of the present invention. It is a side view of a metal core. It is XX arrow directional cross-sectional view of FIG. It is a side view of a metal core. It is the top view which looked at the elastic crawler belt from the grounding surface side. It is a side view which shows the state with which the elastic crawler belt was mounted | worn with the traveling apparatus. It is a top view of the metal core in other embodiments of the present invention. It is a top view which shows the state just before an elastic crawler belt hits a curb.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Elastic track 7 Track body 8 Core metal 9 Wing part 9a Top surface of wing part 9b Bottom surface of wing part 10 Projection part 12 Corner part 14 Lug 12a Back face of corner part 16 Unfolded part 19 Back face of corner part and bottom face of wing part Boundary part 21 with the boundary between the back of the corner and the bottom of the wing

Claims (4)

  In an elastic crawler metal core having a wing portion embedded in a crawler belt main body of an elastic crawler belt and a protrusion protruding from the upper surface of the wing portion, at least one corner of the longitudinal end portion of the wing portion is bent upward. The back surface of the corner portion is inclined with respect to the bottom surface of the wing portion at an angle of 10 ° to 60 °, and a boundary line between the back surface of the corner portion and the bottom surface of the wing portion is formed. An elastic crawler metal core characterized by being inclined at an angle of 30 ° to 70 ° with respect to the longitudinal direction of the wing portion.   The core metal for an elastic crawler belt according to claim 1, wherein a chamfer is applied to a boundary portion between a bottom surface of the wing portion and a back surface of the corner portion.   3. An elastic crawler belt in which the core for elastic crawler belt according to claim 1 or 2 is embedded in a crawler body, wherein a corner on the rear side of the core metal is formed in a bent shape upward. Elastic track.   A plurality of lugs are formed on the outer circumferential surface of the crawler belt main body along the circumferential direction of the crawler belt main body, and the lugs are end portions in the width direction of the crawler belt main body rather than a portion on the center side in the width direction of the crawler belt main body. The elastic crawler belt according to claim 3, wherein the elastic crawler belt is formed in an inclined shape so that the side portion is located rearward.

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