JP6605295B2 - Rubber crawler and method of manufacturing the rubber crawler - Google Patents

Description

  The present invention relates to a rubber crawler and a method for producing the rubber crawler, and more particularly to a rubber crawler formed endlessly by abutting end surfaces of belt-shaped rubber belts and vulcanizing and bonding, and a method for producing the elastic crawler.

  As a general method for producing a rubber crawler, there is a method called feed vulcanization. In this method, first, a belt-shaped rubber belt is manufactured using a mold, and this mold has a cooling zone at both ends in the longitudinal direction and a heating zone at the other portions. For this reason, the belt-like rubber belt manufactured by this mold is maintained in an unvulcanized state at both ends and is vulcanized at other portions. This is a method of manufacturing an endless rubber crawler by joining two rubber belts by vulcanizing and bonding them in a state where the end surfaces of the belt-shaped rubber belts manufactured in this manner are butted together.

  For example, Patent Document 1 discloses a rubber crawler manufacturing method by feed vulcanization. According to this technique, the belt-shaped rubber belt manufactured by the mold used here maintains the state in which the end surface to be bonded to the other belt-shaped rubber belt is sufficiently cooled. It is formed in such a position. This end face is formed in the mold in the cooling zone and at a position sufficiently away from the heating zone. According to this technology, by ensuring that the end face is sufficiently cooled and maintaining an unvulcanized state, sufficient adhesion can be ensured in vulcanization adhesion with other rubber belts. Yes.

JP 2005-280337 A

  However, in the technique according to Patent Document 1, the surfaces of both end portions that are continuous with the abutted end surfaces of the belt-shaped rubber belt of the manufactured rubber crawler are exposed. That is, the surface of the joint portion is exposed. Therefore, when such a rubber crawler is used, stress may concentrate on the portion facing the road surface among the portions where the end surfaces are abutted. For this reason, it is desired to prevent the occurrence of a situation such as a crack at the joint due to stress concentration.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a rubber crawler that is less likely to cause seam cracking and can be used stably, and a method of manufacturing the rubber crawler.

The rubber crawler according to claim 1 for solving the above object is as follows.
In the rubber crawler formed endless by abutting the end faces of the belt-shaped rubber belt and vulcanizing and bonding,
A rubber adhesive member is installed between the abutted end surfaces, and the adhesive member is provided on one or both surfaces of the portion between the abutted end surfaces and the surface of the joined portion in the abutted state. The belt lengthwise cross section having an extending portion is configured in an L shape or a T shape, and the extending portion on the surface of the adhesive member is covered with a rubber covering member. .

  According to this configuration, in a state where the vulcanization adhesion is completed, both the end surfaces continuous to the abutted end surfaces, that is, the surface of the joint portion, the covering member straddles both ends. It is arranged with. The surfaces of both end portions, that is, the joint portions in which the end surfaces are abutted against each other, are not exposed on the surface of the rubber crawler. As a result, when the rubber crawler is bent during use of the rubber crawler, it is possible to avoid stress concentration on the portion where the end faces are brought together, and to accurately prevent so-called seam cracking. it can. In addition, during the vulcanization adhesion, the covering member is caused to have fluidity on the surface of the joint portion and is entangled with each other to achieve strong vulcanization adhesion at the joint portion. Thereby, even if the rubber crawler is bent, it is possible to secure an adhesive force that hardly causes a seam crack.

Furthermore, the adhesiveness between the end surfaces which are abutted by the adhesive member can be further improved. That is, due to the presence of the covering member, the adhesive member disposed between the end faces is not exposed on the surface of the connecting portion, and the function of improving the adhesiveness can be exhibited. Thereby, the durability of the seam of the rubber crawler is further improved.

Further, since the adhesive member has a bent form extending from between the abutted end surfaces to the surface portion of the rubber belt on the side where the covering member is attached, a part of the adhesive member is It can be hooked and installed on the surface portion of the rubber belt, facilitating preparation work for vulcanization adhesion. Furthermore, the flow of rubber at the contact portion between the adhesive member and the covering member can be ensured, and the adhesion at this portion is further improved.

The rubber crawler according to claim 2 is the rubber crawler according to claim 1 ,
The covering member is formed of the same material as the rubber belt.

  According to this configuration, since the chemical properties such as the molecular structure of the material of the covering member and the material of the rubber belt are the same, the conditions such as the temperature for vulcanization are the same. Therefore, good compatibility can be obtained when both are vulcanized and bonded, and more stable adhesion between the covering member and the rubber belt is ensured.

A method of manufacturing a rubber crawler according to claim 3 is as follows:
In the manufacturing method of the rubber crawler formed endless by abutting the end faces of the belt-shaped rubber belt and vulcanizing and bonding,
Adhesion between the abutted end faces and having an L-shaped or T-shaped cross section in the belt length direction, having a part extending between one end or both sides of the face- to- end face portion and the surface of the joined joint portion rubber covering member to cover the adhesive member sandwiching step, the portion extending to the surface and the surface of the adhesive member of the connecting portion in a state where the end face is butted sandwiching the rubber adhesive member having sex And a covering member mounting step for mounting and a vulcanization bonding step for vulcanizing and bonding a nearby region including the connecting portion.

According to this configuration, it is possible to accurately produce a rubber crawler capable of preventing the so-called rubber cracking.

  According to the rubber crawler of the present invention, it is possible to prevent the concentration of stress at the portion where the end faces are brought together in the bending state at the time of use, to prevent the occurrence of so-called seam cracking, and to ensure good durability. be able to.

(A) is length direction sectional drawing of the vicinity area | region containing the joint part of the rubber crawler which concerns on the 1st Embodiment of this invention, (B) is a joint of the rubber crawler which concerns on the 2nd Embodiment of this invention. It is length direction sectional drawing of the near region containing a part. (A) is explanatory drawing of the vulcanization method of the 1st step in the manufacturing method of the rubber crawler which concerns on embodiment of this invention, (B) is explanatory drawing of the vulcanization method of the 2nd step. It is an enlarged view of D section in Drawing 2 (B), (A) is an explanatory view of a characteristic part of a rubber crawler of manufacture, and (B) is an explanatory view of the 1st modification of (A). (A) is explanatory drawing of the 2nd modification of the rubber crawler which concerns on embodiment of this invention in FIG. 3 (A), (B) is explanatory drawing of a 3rd modification similarly.

  Hereinafter, embodiments of a rubber crawler according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 (A) shows an end face 14a of a band-like rubber belt 14 with ends in the rubber crawler 10 according to the first embodiment of the present invention and an end face 16a of a band-like rubber belt 16 with ends. The vulcanized and bonded part is shown. In a state where the end surface 14a and the end surface 16a are in contact with each other, the surfaces of both end portions 14b and 16b that are continuous from the end surfaces 14a and 16a that are in contact with each other, that is, the surface on the side facing the road surface of the connecting portion 17 are covered. A sheet-like rubber covering member 12 is installed. Here, the end portions 14b and 16b indicate portions occupying a certain range of the rubber belts 14 and 16 continuous from the end surfaces 14a and 16a, respectively.

  In the present embodiment, the covering member 12 is made of the same material as the rubber belts 14 and 16. Therefore, since the chemical properties such as the molecular structure and the melting point are the same, the optimum conditions for the temperature and the like when vulcanizing the covering member 12 and the rubber belts 14 and 16 are also common, and good adhesion is achieved. Highly vulcanizable adhesion can be performed.

  As shown in the figure, the covering member 12 is vulcanized and bonded while covering the surface of the connecting portion 17 facing the road surface, and the surface of the covering member 12 is flush with the surfaces of the rubber belts 14 and 16. It has a configuration. Therefore, the portion where the end surfaces 14a and 16a are attached to each other is not exposed on the surface of the rubber crawler 10 facing the road surface, that is, on the outer surface 10-1. Therefore, there is no situation where the vehicle with the rubber crawler 10 is in direct contact with the road surface when traveling. Therefore, it is possible to avoid stress concentration on the portion where the end surface 14a and the end surface 16a are abutted.

  Thereby, even if the situation where the rubber crawler 10 bends during traveling is repeated, the portion where the end surface 14a and the end surface 16a are abutted is torn and cracked, so-called the occurrence of so-called seam cracking is effectively prevented. In addition, during vulcanization and adhesion, flow occurs at the contact portion between the covering member 12 and the rubber belts 14 and 16, so that the covering member 12 and the rubber belts 14 and 16 are good at their contact surfaces. It will be in a good adhesion state.

  FIG. 5B shows a rubber crawler 20 according to the second embodiment of the present invention, and an end surface 14a of the end-like belt-like rubber belt 14 and an end surface of the end-like belt-like rubber belt 16 are shown. A portion vulcanized and bonded by abutting 16a is shown. A different part from the first embodiment is that the covering of the rubber belts 14 and 16 is made between the end face 14a and the end face 16a where the adhesive member 18 made of natural rubber or the like and having adhesiveness is abutted. That is, it extends to the surface portion on the side where the member is attached. Although not shown, the adhesive member 18 extends in the width direction of the rubber crawler 20.

  Since vulcanization is performed with the adhesive member 18 having adhesiveness sandwiched between the end surface 14a and the end surface 16a, the adhesiveness between the end surfaces 14a and 16a is further improved.

  Further, the adhesive member 18 has a substantially L-shaped shape in cross-section in the length direction, and extends to the surface portion of the end portion 16b of the rubber belt 16 on the side where the covering member 12 is attached. . Therefore, the adhesive member 18 can be temporarily installed by hooking the fixed portion 18a on the surface of the end portion 16b of the rubber belt 16 in the preparation stage of vulcanization adhesion, thereby facilitating the work. . In addition, in the case of vulcanization bonding, the bonding member 18 and the covering member 12 flow to ensure a good bonding region.

  Below, the manufacturing method of the rubber crawler concerning an embodiment of the invention is described in detail, referring to drawings.

  FIG. 2A shows the first stage vulcanization in the process which is a premise of the rubber crawler manufacturing method according to the embodiment of the present invention, and FIG. 2B shows the second stage vulcanization. It shows about sulfur. The first stage vulcanization method is the same as the conventional method, and the characteristic part of the rubber crawler manufacturing method according to the embodiment of the present invention is the second stage vulcanization method. .

  The vulcanization bonding apparatus 100 shown in FIG. 1A has three molds, an upper mold 100a, a middle mold 100b, and a lower mold 100c. Each mold has a belt-like shape, and has cooling zones 102 at both ends, and a heating zone 104 at the central portion excluding the cooling zone 102.

  As shown in the drawing, an endless steel cord 30 is installed so as to be sandwiched between the upper mold 100a and the middle mold 100b, and between the lower mold 100c and the middle mold 100b, and the steel cord 30 is sandwiched from above and below. Ended and band-like cap rubbers 22-1 and 22-2 and end-like band-like metal fitting lower rubbers 24-1 and 24-2 are installed. The cap rubbers 22-1 and 22-2 and the under metal fittings 24-1 and 24-2 are in an unvulcanized state. Here, the rubber member having the cap rubber 22-1 and the metal lower rubber 24-1 is replaced with the rubber member 26-1, and similarly, the rubber member having the cap rubber 22-2 and the metal lower rubber 24-2 is converted to the rubber. Let it be the manufacturing member 26-2.

Subsequently, the rubber members 26-1 and 26-2 in a state in which the steel cord 30 is sandwiched between the upper mold 100a and the middle mold 100b, and the lower mold 100c and the middle mold 100b in a state of 117 kgf / cm ² . Pressurize with. At the same time, vulcanization bonding is performed by heating at 160 to 168 ° C. in the heating zone 104. On the other hand, since heating is not performed in the cooling zone 102, the unvulcanized state is maintained in that portion. Thereby, the belt-like rubber belts 14-1 and 14-2 (see FIG. 5B) in which both ends are unvulcanized are formed.

  FIG. 4B shows the steel cord 30 (see FIG. 1A) rotated clockwise from the position of FIG. 1A in a state where the rubber belts 14-1 and 14-2 are formed. It shows a state of being moved. In the second stage, between the rubber belts 14-1 and 14-2, the steel cord 30 is replaced with the cap rubbers 22-3, 22-4 and the under-metal rubber 24 in the same manner as the first-stage vulcanization described above. -3, 24-4, sandwiched from both sides, endless by vulcanizing and adhering the rubber members 26-3, 26-4 and the respective end faces of the rubber belts 14-1, 14-2. A rubber crawler is formed.

  A characteristic part of the manufacturing method of the rubber crawler according to the embodiment of the present invention is a method of vulcanizing and bonding a part (D part shown in FIG. 5B) where the end faces are butted together.

  FIG. 3 is an enlarged view of a portion D in FIG. 2 (B) showing the second stage vulcanization. The adhesive member 18 shown in FIG. 3 (A) has a substantially L-shaped cross-sectional view in the longitudinal direction, the thickness is about 2 mm, the length of the short side of the L-shape is about 20 mm, and the length of the long side is About 30 mm. Then, the short side portion 18a is placed on the surface of the end portion of the cap rubber 22-3, and the long side portion 18b is sandwiched between the end surface of the rubber member 14-1 and the end surface of the rubber member 26-3 (adhesive member). Sandwiching process).

  Then, the covering member 12 is placed so as to cover the surface facing the road surface of the connecting portion 17 in a state in which both end faces of the butted rubber member 26-3 and the rubber member 14-1 are butted. To do. The covering member 12 covers the entire exposed portion of the surface of the rubber member 26-3, which is a part of the adhesive member 18, facing the road surface (covering member placing step). In the present embodiment, the covering member 12 is formed of a sheet-like rubber member having a thickness of 6 mm and a length in the rubber crawler extension direction of 80 mm.

As described above, the vicinity region including the connecting portion 17 where the end of the rubber member 26-3 and the end of the rubber member 14-1 are abutted is sandwiched between the upper mold 100a and the middle mold 100b (FIG. 2 ( B) Reference) Vulcanization adhesion is performed by heating at 160 to 168 ° C. under a pressure of 117 kgf / cm ² (vulcanization adhesion step).

  By performing this process, the endless rubber crawler 20 is formed. Thereby, the rubber crawler provided with the adhesive member 18 having an L-shaped cross section can be accurately manufactured by a simple method.

  In addition, this invention is not limited to the range shown to the said embodiment, A various deformation | transformation is possible within the summary of invention. For example, the longitudinal sectional view shape of the adhesive member 18 is not limited to the above-mentioned L shape, and may be a T shape as shown in FIG.

  According to this configuration, the adhesive member 18-1 is placed on the surface on the side to which the covering member 12 is attached at both ends of the cap rubber 22-3 and the rubber member 14-1. With this configuration, the adhesiveness between the adhesive member 12, the rubber belt 14-1, and the rubber member 26-3 can be further improved.

  Further, as shown in FIG. 4A, the adhesive member 18-2 can be formed in a U-shape in a sectional view in the length direction. According to this configuration, the adhesive member 18-2 is extended not only on the surface of the end portion of the cap rubber 22-3 to which the covering member 12 is attached, but also on the surface of the end portion of the metal lower rubber 24-3. Exist.

  Furthermore, as shown in FIG. 5B, the adhesive member 18-3 is formed in an I-shape in a cross-sectional view in the longitudinal direction without a bent portion, and is not placed on the surface of the end portion of the cap rubber 22-3. The configuration may be such that it is sandwiched between the end surface of -3 and the end surface of the rubber member 14-1. Thereby, manufacture of a connection member is facilitated.

  In addition, the material of the covering member 12 is formed of the same material as that of the rubber belts 14 and 16 in the above embodiment, but it is not necessarily the same, and it is applicable if it is a member having at least close vulcanization conditions. Can do. Furthermore, although the coating member 12 showed the example installed only in each outer surface 10-1, 20-1 of the rubber crawlers 10 and 20, it installed so that the whole surface including the inner side of the face | butt | matching might be wrapped. May be.

  In addition, the size of the covering member is sufficient if it can cover at least the connecting portion. Further, the size of the adhesive member is at least sandwiched by a predetermined range of the end surfaces of the end portions to be secured to ensure accurate adhesiveness. Any size that is possible is sufficient.

DESCRIPTION OF SYMBOLS 10 Rubber crawler 10-1 which concerns on 1st Embodiment Outer surface 10-2 of rubber crawler 10 Inner surface 12 of rubber crawler 10 Cover member 14, 16 Rubber belt 14a End surface 14b of rubber belt 14 Rubber belt 14 End portion 16a End surface 16b of rubber belt 16 End portion 17 of rubber belt 16 Joint portion 18 18-1, 18-2, 18-3 Adhesive member 20 Rubber crawler 20-1 according to the second embodiment Rubber Outer surface 20-2 of crawler 20 Inner surfaces 22-1, 22-2, 22-3, 22-4 of rubber crawler 20 Cap rubber 24-1, 24-2, 24-3, 24-4 Rubber under metal 26 -1 Rubber member 26-2 having cap rubber 22-1 and metal lower rubber 24-1 Rubber member 26-3 having cap rubber 22-2 and metal lower rubber 24-2 Pugomu 22-3 and rubber member 30 steel cord having a rubber member 26-4 cap rubber 22-4 and fitting rubber under 24-4 having a fitting rubber under 24-3

Claims (3)

In the rubber crawler formed endless by abutting the end faces of the belt-shaped rubber belt and vulcanizing and bonding,
A rubber adhesive member is installed between the abutted end faces,
The adhesive member includes a portion between the abutted end surfaces and a portion extending on one or both surfaces of the surface of the joined portion in the abutted state. T-shaped configuration,
The rubber crawler characterized in that the extending portion of the surface of the adhesive member is covered with a rubber covering member . The rubber crawler according to claim 1 , wherein the covering member is made of the same material as the rubber belt. In the manufacturing method of the rubber crawler formed endless by abutting the end faces of the belt-shaped rubber belt and vulcanizing and bonding,
Adhesion between the abutted end faces and having an L-shaped or T-shaped cross section in the belt length direction, having a part extending between one end or both sides of the face- to- end face portion and the surface of the joined joint portion An adhesive member sandwiching step for sandwiching a rubber adhesive member having a property;
A covering member mounting step of mounting a rubber covering member so as to cover the surface of the joint portion in a state where the end faces are in contact with each other and the portion extending to the surface of the adhesive member;
A vulcanization bonding step of vulcanizing and bonding a neighboring region including the joint portion;
A method for producing a rubber crawler, comprising:

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