JP4860447B2 - Rubber crawler - Google Patents

Description

  The present invention relates to a rubber crawler mounted on a traveling device such as an agricultural machine or a construction machine.

In this type of rubber crawler, for example, a plurality of lugs are formed at intervals on the outer peripheral surface of an endless belt-like crawler body, and a cored bar is embedded in the crawler body (see, for example, Patent Document 1).
The metal core has a plate-like wing portion embedded in the crawler main body and a pair of protrusions formed on the upper surface of the wing portion so as to protrude from the crawler main body.

The protruding portion of the core bar guides the traveling device so that it can travel on a predetermined track so that the wheels of the traveling device do not come off. The wheel of the traveling device rotates in contact with the inner peripheral surface of the crawler body while straddling the protrusion.
JP 2006-111113 A

In a conventional rubber crawler, a rubber portion (hereinafter referred to as a “rolling wheel passing portion”) through which a roller wheel contacts and passes on the inner peripheral surface of the crawler body includes a portion sandwiched between the core metal and the wheel.
Since this portion is more strongly pressed by the roller and the core than the other portions, cracks are likely to occur. If a crack occurs in this part, the peeling of the rubber progresses, and it becomes a worm-eaten (rubber chip cut) state and cannot be used.

  This invention is made | formed in view of such a situation, and it aims at providing the rubber crawler which made it hard to produce the worm-eaten of the wheel passing part of the internal peripheral surface of a crawler main body.

In order to solve the above problems, the present invention has taken the following technical means.
That is, the present invention
Core metal having a projecting portion projecting from the blade portion and the crawler body to be embedded in the endless belt-like crawler body is provided at intervals in the crawler body, the rolling wheel of the traveling device is of the core In the rubber crawler configured to pass across the protrusion, the inner peripheral surface of the crawler body is formed with a wheel passing portion through which the wheel contacts and passes, and the wing portion of the core metal , the crawler body made form a through hole at a position overlapping to the rotary wheel passing portion when viewed from the side of the inner peripheral surface, to the inner peripheral surface of the opening edge portion is curved in the through-hole The radius of curvature of the edge is 2/5 or more of the thickness of the wing portion of the core metal, and the aspect ratio of the cross section of the wing portion at the position where the through hole is formed is 0.25 or more. It is said that it is said.

  Thus, by providing the through hole of the wing part of the cored bar at a position corresponding to the wheel passing part, the rubber at this position is easily elastically deformed, and the rubber part of the crawler main body becomes the wheel when passing the wheel. The degree of being crushed by the wings can be reduced. In addition, by forming the edge of the through hole on the upper surface of the wing part into a curved surface having a predetermined size, it is possible to reduce stress concentration on the edge and prevent the rubber part in the vicinity from cracking. .

As described above, the rubber crawler according to the present invention is less likely to cause worm-eating at the wheel passing portion.
In addition, by setting the aspect ratio of the wing section of the core metal to 0.25 or more, the core metal can ensure sufficient strength even if the through hole is provided in the wing section.
The present invention also provides:
Core metal having a projecting portion projecting from the blade portion and the crawler body to be embedded in the endless belt-like crawler body is provided at intervals in the crawler body, the rolling wheel of the traveling device is of the core In the rubber crawler configured to pass across the protrusion, the inner peripheral surface of the crawler body is formed with a wheel passing portion through which the wheel contacts and passes, and the wing portion of the core metal a recess made form the crawler body at positions overlapping in the rolling wheel passing portion when viewed from the side of the inner peripheral surface, the recess has a width in the longitudinal direction of the core metal is the rotary wheel passing portion and a width less than the depth of the recess are 2/5 or more of the thickness of the wing portion, the is formed in the opening edge portion is curved concave, the radius of curvature of the edge The thickness of the wing part of the metal core is 2/5 or more, and the wing part is cut off at the position where the recess is formed. Aspect ratio is characterized in that it is 0.25 or more.

  In this way, by forming a recess having a predetermined depth in the wing portion of the metal core and providing this recess at a position corresponding to the wheel passing portion, the rubber at this position is easily elastically deformed, and the wheel passes. The degree to which the rubber part of the crawler body is sometimes crushed by the wheels and wings can be alleviated. Further, by forming the edge of the concave portion on the upper surface of the wing portion into a curved surface having a predetermined size, it is possible to reduce stress concentration on the edge and prevent cracks from occurring in the nearby rubber portion.

As described above, the rubber crawler according to the present invention is less likely to cause worm-eating at the wheel passing portion.
Further, by setting the aspect ratio of the cross section of the wing portion of the core metal to 0.25 or more, the core metal can ensure sufficient strength even if the wing portion is provided with a recess.
Further, in the present invention, the width of the through hole or the concave portion is set to ¼ or more and ½ or less of the width of the wing portion of the core metal, and the through hole or the concave portion is arranged in the width direction of the core metal. It is provided in the center position.

According to this, by forming the through-hole or the concave portion to a predetermined size, the rubber portion near the through-hole or the concave portion is easily elastically deformed, and thereby, the worm-eaten portion of the wheel passing portion is hardly generated.
Further, the present invention is characterized in that the length of the through hole in the longitudinal direction of the wing portion of the cored bar is substantially equal to or less than the width of the wheel passing portion.

According to this, by setting the through- hole to a predetermined size, it is difficult to cause worm-eaten in the wheel passing portion while ensuring the strength of the cored bar sufficiently.

  ADVANTAGE OF THE INVENTION According to this invention, it can be made hard to produce the worm-eaten of the wheel passing part of the inner peripheral surface of a crawler main body.

The best mode for carrying out the present invention will be described below with reference to the drawings.
1 to 5 show an embodiment of a rubber crawler 1 according to the present invention.
A rubber crawler 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, as illustrated in FIG. 5, 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 rubber crawler 1 is wound around each wheel of the traveling device 2 and is driven by the sprocket 4 to travel.

As shown in FIG. 5, the rubber crawler 1 has an endless belt-like crawler body 7. The crawler body 7 is formed in an endless shape by vulcanizing and molding rubber. Hereinafter, the band longitudinal direction of the crawler main body 7 is simply referred to as “circumferential direction” (indicated by symbol A in the drawing), and the band width direction orthogonal to the circumferential direction A is simply referred to as “width direction” (reference symbol in the drawing). B).
Further, the direction from the end portion 7a in the width direction B of the crawler body 7 to the center C (indicated by a one-dot chain line in FIG. 1) in the width direction B of the crawler body 7 is referred to as “width direction inward”. A direction from the center C in the width direction B of the crawler body 7 toward the end portion 7a in the width direction B of the crawler body 7 is referred to as “outward in the width direction”.

Further, in the thickness direction of the crawler body 7, the direction from the outer peripheral surface 7c of the crawler main body 7 to the inner peripheral surface 7b is referred to as “inward”, and the direction from the inner peripheral surface 7b to the outer peripheral surface 7c is “outward”. That's it.
A plurality of lugs 11 are formed along the circumferential direction A on the outer peripheral surface 7 c of the crawler body 7. On the outer peripheral surface 7 c of the crawler body 7, long lugs 11 a having a long length in the width direction B and short lugs 11 b having a short length in the width direction B are alternately formed along the circumferential direction A. In addition, the shape, arrangement | positioning, etc. of this lug 11 are not restricted to this, The lug 11 with the same length of the width direction B may be formed, and the lugs 11 may be what is called zigzag arrangement.

A plurality of core bars 8 are embedded in the crawler body 7. Further, an endless tensile body 12 is embedded on the outer side of the cored bar 8.
The cored bar 8 is provided at a predetermined pitch along the circumferential direction A of the crawler body 7. The cored bar 8 has a rectangular shape in plan view. Hereinafter, a direction orthogonal to the longitudinal direction D of the cored bar 8 is referred to as a “width direction E of the cored bar 8”.

The cored bar 8 has a wing part 8a embedded in the crawler body 7 and a protruding part 8b formed to protrude from the upper surface 9 of the wing part 8a. As shown in FIGS. 1 to 3, two wing portions 8 a and two protrusions 8 b are formed on one cored bar 8.
The two protrusions 8 b are formed at a predetermined interval in the longitudinal direction D of the cored bar 8. Each protrusion 8b is provided so as to protrude from the crawler body 7 toward the inner peripheral surface 7b (inward).

  The wheel 6 of the traveling device 2 travels in contact with the inner peripheral surface 7b of the crawler body 7 while straddling the protrusion 8b of the core metal 8 (Matagi wheel). Hereinafter, the portion of the inner peripheral surface 7b of the crawler body 7 through which the rollers 6 are in contact with each other is referred to as a wheel passage portion 13. The wheel passing portion 13 is provided on the inner peripheral surface 7 b of the crawler main body 7 at a position inward in the width direction (position near the protruding portion 8 b of the core metal 8).

Each wing portion 8a of the core metal 8 is formed with a through hole 15 penetrating in the thickness direction. The through hole 15 is formed at a position near the base 17 of the protrusion 8 b of the cored bar 8.
As shown in FIG. 3, the through hole 15 is formed in a substantially rectangular shape in plan view. The through hole 15 is formed with a predetermined length L1 in the longitudinal direction D of the cored bar 8 and a predetermined width w in the width direction E of the cored bar 8. The through hole 15 is formed such that the length L1 of the cored bar 8 in the longitudinal direction D is larger than the width w of the cored bar 8 in the width direction E. The width w of the through hole 15 is desirably ¼ or more and ½ or less of the width W of the wing portion 8a, more preferably ３ or more and ½ or less. .

As shown in FIG. 1, the through hole 15 is disposed at a position corresponding to the wheel passing portion 13 of the crawler body 7. The through hole 15 is provided at the center position in the width direction E of the cored bar 8.
As shown in FIG. 4, the edge 16 of the through hole 15 on the upper surface 9 side of the wing portion 8a of the cored bar 8 is chamfered (R chamfered) and formed into a curved surface. The radius of curvature of the edge 16 of the through-hole 15 is preferably 2/5 or more of the thickness T of the wing 8a of the cored bar 8.

  As shown in FIG. 4, it is desirable that the aspect ratio of the cross section of the wing portion 8a of the cored bar 8 at the position where the through hole 15 is formed is 0.25 or more. Here, the aspect ratio of the cross section of the wing portion 8a of the cored bar 8 is the thickness T of the wing portion 8a at the position where the through hole 15 is provided (for example, the position indicated by the arrow FF in FIG. 3). And the width W of the wing portion 8a (referring to the length of the wing portion 8a in the width direction of the core 8) (T / W).

The length L1 of the through hole 15 in the longitudinal direction D of the cored bar 8 is preferably set to be substantially equal to or less than the width L3 of the wheel passing portion 13. Here, the width L3 of the wheel passing portion 13 refers to the length of the wheel passing portion 13 in the width direction B of the crawler body 7 (see FIG. 1 and the like).
According to the rubber crawler 1 having the above-described configuration, the through hole 15 formed in the wing portion 8a of the core metal 8 is provided at a position corresponding to the wheel passing portion 13 of the crawler main body 7. Therefore, the core metal 8 Even when the wheel 6 is placed on the wheel passage portion 13 corresponding to the above, the stress concentration of the rubber portion between the core metal 8 and the wheel 6 can be reduced.

That is, when the roller 6 is located at a position corresponding to the metal core 8, the stress acting on the rubber portion sandwiched between the metal core 8 and the roller 6 is transmitted through the through hole 15 of the wing portion 8 a of the metal core 8. 8 acts on the outer rubber part (the lug 11 side). As a result, the stress concentration acting on the rubber portion sandwiched between the cored bar 8 and the roller 6 is alleviated, and the rubber crawler 1 is less likely to cause cracks and insect bites in the roller passage portion 13.

Further, since the edge portion 16 of the through hole 15 on the upper surface 9 of the wing portion 8a is chamfered in a curved shape, stress concentration can be prevented from occurring on the edge portion 16, and thereby, the position near the edge portion 16 can be prevented. Can prevent cracks from occurring.
Further, by setting the aspect ratio of the cross section of the wing portion 8a at the position where the through hole 15 is formed within a predetermined range, the cored bar 8 has sufficient strength even if the through hole 15 is formed in the wing portion 8a. It can be secured.

6 to 8 show another embodiment of the present invention.
In this embodiment, the wing portion 8a of the metal core 8 is formed with a recess 18 at a position corresponding to the wheel passing portion 13, and this point is different from the embodiment of FIGS. The recess 18 is not penetrated in the thickness direction of the cored bar 8. The concave portion 18 is formed at a position near the base portion 17 of the protruding portion 8 b of the cored bar 8.

  The depth t of the concave portion 18 is set to 2/5 or more of the thickness T of the wing portion 8a of the cored bar 8. The edge 19 of the recess 18 in the upper surface 9 of the wing 8a is chamfered (R chamfered) and formed into a curved surface. It is desirable that the radius of curvature of the edge portion 19 is 2/5 or more of the thickness T of the wing portion 8a of the cored bar 8. It is desirable that the aspect ratio of the cross section of the wing portion 8a at the position where the concave portion 18 of the metal core 8 is provided is 0.25 or more.

Moreover, it is desirable that the width w of the concave portion 18 is not less than 1/4 and not more than 1/2 of the width W of the wing portion 8a.
Moreover, it is desirable that the length L1 of the recess 18 in the longitudinal direction D of the cored bar 8 is substantially equal to or less than the width L3 of the wheel passing portion 13.
Other configurations in this embodiment are substantially the same as those in the embodiments of FIGS. 1 to 5, and parts having the same configurations are denoted by common reference numerals.

Also in this embodiment, by forming the recess 18 at a position corresponding to the wheel passing portion 13, the stress concentration between the wheel and the cored bar 8 is alleviated as in the embodiment of FIGS. 1 to 5. It is possible to make it difficult for cracks and worms to be generated in the wheel passing portion 13.
FIG. 9 shows a reference form.
This reference form is the same as the embodiment of FIGS. 6 to 8 in that a recess 18 formed in the wing part 8a is formed. The concave portion 18 is formed from the position near the base portion 17 of the protruding portion 8b of the cored bar 8 to the end portion of the wing portion 8a, and this point is different from the embodiment of FIGS. Other configurations are the same as those in the embodiment of FIGS. 6 to 8, and parts having the same configurations are denoted by common reference numerals.

Also in this reference form, by forming the recess 18 at a position corresponding to the wheel passing portion 13, the wheel and the core metal are the same as in the embodiment of FIGS. 1 to 5 and the embodiment of FIGS. 6 to 8. The stress concentration between 8 can be relaxed, and cracks and worm bites of the wheel passing portion 13 can be made difficult to occur.
The applicant conducted a test to confirm the effect of the present invention. In this test, the core bar 8 has different widths, thicknesses, and the like (Examples 1 to 8, 12, and 13 in which the recess 18 is formed in the wing part 8a, and Example 9 in which the through hole 15 is formed in the wing part 8a. To 11), and a comparative example (Comparative Example 1 (conventional example) in which the concave portion 18, the through hole 15 and the like are not formed in the wing portion 8a) was manufactured, and mounted on a traveling device to travel on the road.

  In the test, each example and comparative example was run until worm-eaten was generated, and the superiority or inferiority was judged by comparing the time. In addition, the standard for insect erosion resistance (difficulty of occurrence of worm erosion) is defined as 100 as the time until worm erosion occurs in the wheel passing portion 13 of Comparative Example 1 (conventional example) in which the recess 18 and the through hole 15 are not formed in the wing portion 8a The insect erosion resistance was evaluated by indexing the values and comparing other examples and comparative examples with these values.

Insect erosion resistance means that the larger the value, the longer the time until worm erosion occurs and the less worm erosion occurs.
The test results are shown in Table 1.
In Table 1, “T / W” indicates the aspect ratio of the cross section of the wing portion 8a at the position where the recess 18 or the through hole 15 is formed.

In Table 1, “t / T” indicates the ratio between the depth t of the recess 18 and the thickness T of the wing portion 8a. In Table 1, when t / T is 1, it means that the through hole 15 is formed in the wing portion 8a.
In Table 1, “w / W” indicates the ratio between the width w of the recess 18 or the through hole 15 in the width direction E of the cored bar 8 and the width W of the wing portion 8 a of the cored bar 8.

In Table 1, “durability” is determined based on the section modulus of the cored bar 8. This durability means that the greater the value, the higher the strength of the cored bar 8.

According to this test, when the recessed part 18 was formed in the wing | blade part 8a like Examples 1-11, 13, the depth t of the recessed part 18 is 2/5 or more (0. 4), it was found that the insect resistance was improved.
Further, as in Examples 1 to 10 and Example 12, when the width w of the through hole 15 or the recess 18 is ¼ or more and ½ or less of the width W of the wing portion 8a of the core metal 8, insect resistance It turns out that the eating property improves.

  INDUSTRIAL APPLICABILITY The present invention can be used for a rubber crawler mounted on a traveling device such as an agricultural machine or a construction machine.

It is sectional drawing of the rubber crawler in one Embodiment of this invention. It is a perspective view of a core metal. It is a top view of a metal core. FIG. 5 is a cross-sectional view taken along line FF in FIG. 3. It is a side view which shows the state with which the rubber crawler was mounted | worn with the traveling apparatus. It is a top view of the metal core which concerns on other embodiment of this invention. It is a top view of a metal core. FIG. 8 is a cross-sectional view taken along line GG in FIG. 7. It is sectional drawing of the rubber crawler in a reference form.

DESCRIPTION OF SYMBOLS 1 Rubber crawler 2 Traveling device 6 Roller 7 Crawler main body 8 Core metal 8a Wing part 8b Projection part 9 Upper surface of wing part 13 Roller wheel passage part 15 Through hole 16 Edge part 17 Protrusion base part 18 Recess part 19 Edge part

Claims (4)

A cored bar having a wing portion embedded in an endless belt-like crawler body and a protruding part protruding from the crawler body is provided in the crawler body at an interval, and the wheel of the traveling device projects from the cored bar. In rubber crawlers configured to pass across parts,
On the inner peripheral surface of the crawler body, a wheel passing portion through which the wheel contacts and passes is formed.
The wings of the metal core, the through-holes of the crawler body at positions overlapping in the rolling wheel passing portion when viewed from the side of the inner peripheral surface is made form,
Said edge portion of the inner peripheral surface side opening of the through hole is formed in a curved shape,
The radius of curvature of this edge is set to 2/5 or more of the thickness of the wing part of the core metal,
A rubber crawler characterized in that the aspect ratio of the cross section of the wing at the position where the through hole is formed is 0.25 or more. A cored bar having a wing portion embedded in an endless belt-like crawler body and a protruding part protruding from the crawler body is provided in the crawler body at an interval, and the wheel of the traveling device projects from the cored bar. In rubber crawlers configured to pass across parts,
On the inner peripheral surface of the crawler body, a wheel passing portion through which the wheel contacts and passes is formed.
The wings of the metal core, the recess is made form the crawler body at positions overlapping in the rolling wheel passing portion when viewed from the side of the inner peripheral surface,
The concave portion has a width in the longitudinal direction of the core metal equal to or less than a width of the wheel passing portion,
The depth of the recess is 2/5 or more of the thickness of the wing,
Edge of the opening of the recess is formed in a curved shape,
The radius of curvature of this edge is set to 2/5 or more of the thickness of the wing part of the core metal,
A rubber crawler characterized in that the aspect ratio of the cross-section of the wing at the position where the recess is formed is 0.25 or more. The width of the through hole or the width of the recess is ¼ or more and ½ or less of the width of the wing,
The rubber crawler according to claim 1 or 2, wherein the through-hole or the concave portion is provided at a center position in a width direction of the cored bar. Rubber crawler as claimed in claim 1, characterized in that it is the width of the long saga track roller passing portion of the through hole and substantially equal or less in the longitudinal direction of the metal core.