JP2001047436A - Manufacture of rubber crawler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a ply separation of rubbery reinforcing cord or the like, chipping of a rubber, to prevent bare of the rubber and to also prevent a wave of a crawler and a decrease in a pitch accuracy by enhancing an adhesive strength of each part of a belt like rubber endless connecting portion. SOLUTION: The method for manufacturing a rubber crawler comprises the steps of constituting a band-like rubber 1 embedding reinforcing cords 8 by one time vulcanization molding, superposing and connecting both, end portions 9 of the rubber 1. In this case, the portions 9 of the rubber 1 are molded in an unvulcanized or semi-cured state. Added volume of the portions 9 is constituted larger than a predetermined volume after vulcanizing and connecting. When the portions 9 are vulcanized and connected, excess rubbers of the portions 9 are introduced to a rubber escape portion of a vulcanizing mold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a rubber crawler used in a snowmobile obtained by modifying a recreational vehicle, in addition to an agricultural machine, a construction vehicle, and a snowmobile.

[0002]

2. Description of the Related Art For example, when a rubber crawler is manufactured by endlessly laminating and joining a belt-like rubber having a reinforcing cord embedded therein, FIG. 9A is a schematic cross-sectional view along the length direction. And a pair of upper and lower molds 101 and 102
The rubber material is pressurized and heated in the molding cavity 103 defined by the above, and is molded and vulcanized, and the band-shaped rubber 104 manufactured in such a single vulcanization molding step is stepwise thinned. As shown in a schematic cross-sectional view of FIG. 9B, the both end portions thus formed are overlapped and joined by pressurizing and heating with a joining mold 105. In addition, the belt-shaped rubber itself is joined to FIG. As shown in FIG. 5, rubber blocks 104 sequentially added by repeating a plurality of feed vulcanization moldings from one end to the other end of a pair of upper and lower molds 106.
The step-like thin portions at both ends of the belt-shaped rubber 104 are directly overlapped and joined by a joining mold 105 as shown in FIG. Is being done.

As in the latter case, the belt-like rubber 10
When 4 is formed by a plurality of feed vulcanization moldings, its endless joining is, for example, as shown in FIG.
Under the required overlapping position of the reinforcing cord 104b protruding from each end of the belt-shaped rubber 104 and extending in the longitudinal direction thereof, the uncured inner periphery of a separately molded or unmolded uncured inner periphery is formed in the overlapping region. Surface member 107 and outer peripheral surface member 10
8 may be further superimposed, and both members 107 and 108 may be indirectly integrated with the belt-shaped rubber 104 by vulcanization molding using a joining mold 109.

When manufacturing a crawler comprising an endless rubber ring having a reinforcing cord embedded therein, a plurality of aligned reinforcing cords are connected endlessly in advance, or one reinforcing cord is spirally formed. Under the wound state, for example, as shown in FIG. 12, each of the rubber blocks 112 is mutually vulcanized based on repetition of the feed vulcanization molding of the mold 110 along the reinforcing cord 111 thereof. It is known that they are sequentially added by sulfuric bonding to finally form an endless structure.

[0005]

By the way, in such a manufacturing method, both ends of the belt-shaped rubber 104 are connected to each other as shown in FIG.
10 (b) and FIG. 10 (b), when vulcanizing and joining by overlapping, both ends of the belt-shaped rubber 104 are subjected to vulcanization molding of the rubber itself to be in an unvulcanized or semi-vulcanized state. Is preferable in order to increase the adhesive strength between the end portions and between each end portion and the reinforcing cord. This is because the band-shaped rubber 104 shown in FIG.
In the indirect endless joining of the rubber band 10
4, the inner peripheral member 107 and the outer peripheral member 108
The same applies to bonding to the reinforcing cords 104b.

When each of the belt-shaped rubber 104 and the endless rubber ring is constituted by sequentially adding rubber blocks 104a and 112 as shown in FIGS. Block 1
In the vulcanization molding of 04a, 112, it is preferable to form the additional side end portion of the next block of the rubber block in an unvulcanized or semi-vulcanized state, also from the viewpoint of increasing the adhesive strength to each part. .

However, in reality, in rubber crawlers manufactured in this way, separation between rubbery materials is still difficult.
In addition to peeling of rubbery material from the reinforcing cord, rubber chipping may occur, and a bear may occur on the molding surface.

An object of the present invention is to solve such a problem.
By further increasing the adhesive strength of each component at the endless joint of the band-shaped rubber, the additional joint of each rubber block, etc., the occurrence of delamination of rubber, reinforcing cords and the like, rubber chipping, etc., Rubber that can also prevent the occurrence of bears and that can prevent the occurrence of waves on the rubber crawler, and hence the pitch accuracy of the rubber crawler, without fine adjustment of the rubber volume. A method of manufacturing a crawler is provided.

[0009]

According to a method of manufacturing a rubber crawler of the present invention, a belt-like rubber having a reinforcing cord embedded therein is formed by one vulcanization molding, and both ends of the belt-like rubber are overlapped and joined. In manufacturing the rubber crawler, both ends of the belt-shaped rubber are molded in an unvulcanized or semi-vulcanized state, and the added volume of the both ends is configured to be larger than a required volume after the vulcanization bonding, At the time of the vulcanization joining of the both end portions, the surplus rubber of the both end portions is caused to flow into the rubber escape portion of the vulcanization molding die.

In this method, almost all of the end portions of the rubber band, for example, which are subjected to vulcanization bonding by a vulcanization molding die for bonding, are not vulcanized during vulcanization molding of the rubber band itself. By making it vulcanized or semi-vulcanized,
As described above, the end portions can be joined with high adhesive strength, and the added volume of both unvulcanized end portions and the like should be larger than the required volume after vulcanized joining in the same region. By this, when both ends of the belt-shaped rubber are vulcanized and joined by a joining mold, a sufficiently large pressing force is applied to those ends and the rubber can be sufficiently flown in the cavity, and as a result, As a result, the adhesive strength between the end portions of the belt-like rubber and between the rubber material of each end portion and the reinforcing cord or the like is greatly increased, and the occurrence of delamination, rubber chipping, etc. during use of the rubber crawler is effectively prevented. That is, the occurrence of bear on the crawler surface is also prevented.

The ratio of the added volume to the required volume after the vulcanization bonding is preferably more than 100% and not more than 120% per one pitch of the rubber track. That is, if it is 100% or less, it is impossible to generate a large pressing force at the time of vulcanization bonding, and if it exceeds 120%, the material yield is greatly reduced.

On the other hand, when a surplus volume with respect to a required volume after the vulcanization bonding is sealed in the cavity, the rubber material of the surplus volume is often burred from the split position of the vulcanization mold. In this case, due to the fact that the internal pressure of the cavity becomes considerably higher than a predetermined value, the reinforcing cord disposed in the cavity has a direction in which the rubber crawler is convex or concave outward in the width direction. Deformation, or deformation that gives rise to a wavy shape in the vertical direction of the crawler plane may occur, thereby making the width of the rubber crawler, the ground contact property, etc. non-uniform, and the deformation of the reinforcing cord. There was a delight that the pitch length of the rubber track at the vulcanized joint was shorter than that of the other parts.

Therefore, here, a rubber escape portion into which surplus rubber can flow relatively easily is provided on, for example, a split surface of the vulcanization molding die for joining or at least one of the paired dies. At the time of vulcanization joining of both end portions of the above, by flowing excess rubber to the escape portion, it is possible to prevent an excessive increase in the internal pressure of the cavity, and as described above, the reinforcing cord, and thus, the waving of the rubber crawler, The possibility that the pitch accuracy of the rubber track is reduced due to the deformation of the reinforcing cord is sufficiently removed.

In another manufacturing method of the present invention, a belt-like rubber having a reinforcing cord embedded therein is constituted by a continuous body of a rubber block sequentially added by a plurality of feed vulcanization moldings from one end to the other end, In producing a rubber crawler by directly or indirectly endlessly joining both end portions of the belt-shaped rubber, a rubber block to be vulcanized and molded first,
Subsequently, the end portion on the connection side to the rubber block to be vulcanized and formed is, for example, over the range of one pitch of the crawler
At the time of the previous vulcanization molding, it is molded in an unvulcanized or semi-vulcanized state, and its end portion is made larger than a predetermined volume for one crawler pitch, for example, after vulcanization molding. When the rubber block is added to the end portion, the excess rubber at the end portion on the connection side is positively flowed into the rubber escape portion of the vulcanization mold.

According to this, when the rubber blocks are sequentially added by repeating the vulcanization molding, the end portions of the rubber blocks which have been unvulcanized by the previous vulcanization molding are replaced by the normal state in the subsequent vulcanization molding step. The end portion is unvulcanized or semi-vulcanized by placing it in the mold cavity and applying the same pressure and heating to the end portion as the rubber material for forming the adjacent rubber block. The volume of the end portion is larger than the volume of the corresponding mold cavity portion, and based on being greatly compressed in vulcanization molding, the end portion of the previously vulcanized rubber block is later It can be firmly adhered to each layer of the vulcanized rubber block, thereby preventing the occurrence of bear, and also effectively removes rubber crawler interlayer delamination, rubber chipping, etc. To prevent Door can be.

In this case, too, the excess rubber at the end portion is removed so as to prevent the connection end portion having a large volume from being pressed to a pressure far exceeding a predetermined value in the normal cavity. Then, the rubber crawler is caused to flow into the rubber escape portion of the vulcanization molding die, thereby preventing the rubber crawler from waving and preventing the rubber crawler from lowering in pitch accuracy.

Preferably, in such a production method,
The end portion of the rubber block to be vulcanized and molded first and endlessly on the endless joining side is molded in an unvulcanized or semi-vulcanized state, and, at the same time, an added volume of both end portions thereof is added after vulcanization joining The volume is larger than the required volume, or the volume of each end portion is larger than the required volume after the vulcanization molding.

According to the former, a high adhesive force can be secured when the both ends of the band rubber are overlapped and joined as described above. According to the latter, both ends of the band rubber are joined together. In addition to the case of direct butt joining, in the case of indirect joining by interposing unvulcanized rubber between both end portions, a large adhesive force can be exhibited for the same reason as described above. .

By the way, in the former case, at the time of vulcanization joining of both ends of the belt-shaped rubber, the surplus rubber of those both ends is caused to flow into the rubber escape portion of the vulcanization mold, and in the latter case, However, at the time of vulcanization molding of each end portion of the belt-shaped rubber, the excess rubber at each end portion is caused to flow into the rubber escape portion of the vulcanization molding die, thereby confining the excess volume in the cavity as described above. Can be effectively prevented from occurring. In addition, in the latter case, the belt-shaped rubber is formed by one vulcanization molding, and when both ends are directly butt-joined, and when indirectly joined in the presence of unvulcanized rubber, The both ends of the belt-shaped rubber are molded in an unvulcanized or semi-vulcanized state, and the volume of each end is made larger than a required volume after vulcanization molding, and vulcanization molding of each end is performed. The same applies to the case where the surplus rubber at each end portion is sometimes caused to flow into the rubber escape portion of the vulcanization mold.

In still another manufacturing method of the present invention, for example, a rubber crawler comprising an endless rubber ring in which an endlessly connected or spirally wound reinforcing cord is embedded is sequentially formed by feed vulcanization molding a plurality of times. In forming the endless structure of the rubber block to be added to the above, the end portion of the rubber block that is first vulcanized and formed on the connection side to the block that is subsequently vulcanized and formed is subjected to the above vulcanization and molding. In this case, the molding is carried out in an unvulcanized or semi-vulcanized state, and the end portion is constituted to have a volume larger than a predetermined volume after vulcanization molding, for example, a volume exceeding 100% and 120% or less. Further, when a rubber block is added to an end portion on the connection side, surplus rubber at the end portion is caused to flow into a rubber escape portion of a vulcanization molding die.

In this manufacturing method, the connection strength between the rubber blocks can be increased in the same manner as in the previous case, whereby the occurrence of peeling between blocks, various kinds of interlayer peeling, and chipping of rubber can be sufficiently prevented. , Can also be prevented from occurring. In this case, too, an excessive increase in the internal pressure of the cavity can be advantageously prevented based on the excess rubber and the outflow from the cavity.

In this production method, with respect to the rubber block to be vulcanized first, the end opposite to the above-mentioned end is also molded in an unvulcanized or semi-vulcanized state. It is preferable that the volume is larger than the required volume after vulcanization molding, and at the time of vulcanization molding of the end portion, excess rubber flows into the rubber escape portion of the vulcanization molding die. Can be greatly increased when integrally connected to a rubber block to be finally vulcanized and formed, and an excessive increase in cavity internal pressure can be prevented.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a vulcanization mold used for carrying out one method according to the present invention. This is a relatively short band of rubber 1
Is manufactured by one vulcanization molding, and comprises an upper mold 3 and a lower mold 4 which are positioned opposite to each other to define a molding cavity 2 made of a rubber material.

Here, the upper and lower dies 3, 4 are:
It has a molding surface of the lug 5 located on the outer peripheral surface of the rubber track and a surface for receiving the core 6 located on the inner peripheral surface side of the rubber crawler or forming a driving projection. The molding cavity 2 defined by the molds 3 and 4 has a stepped cavity depth at both ends thereof for the endless joining of the end portions of the band-shaped rubber 1, and furthermore, the molding cavity 2 has a stepped shape. It has a volume reducing portion 7 reduced from the opposite side.

Thus, the band-like rubber 1 vulcanized and molded by such a vulcanization mold has therein at least one reinforcing cord 8 which extends in the longitudinal direction of the rubber band.
In addition, each of the upper and lower surfaces has an uneven portion having a shape and size as required, and a thin portion 9 for overlap joining at both ends. When the belt-like rubber 1 is joined endlessly, as shown in FIG.
By superposing and applying pressure and heating to both of them, it functions to realize vulcanized joining without a thickness step.

As shown in FIG. 1, a water jacket 11 is provided at a portion of the vulcanization mold that contributes to the formation of the thin portion 9, in other words, at a portion corresponding to the volume reducing portion 7. Thus, at the time of operation of the vulcanization molding die, both end portions of the die are made into the non-vulcanization molding region 12 and the remaining portion is made into the vulcanization molding region 13.

In addition, here, for example, the added volume of each volume reduction section 7 is changed to the endless vulcanization mold 10.
In the vulcanization molding of the rubber band 1 by the vulcanization molding die,
The thin portions 9 formed by the respective volume reducing portions 7 are set in an unvulcanized or semi-vulcanized state, and the added volume of the two thin portions 9 is larger than a required volume after both of them are vulcanized and joined. I do.

Therefore, when the two thin portions 9 of the belt-shaped rubber 1 are vulcanized and joined by the endless vulcanization molding die 10, the thin portions 9 are smoothly plastic-flowed under the action of a large pressing force. As a result, the thin-walled portions 9 can be firmly adhered to the reinforcing cords 8 and the like, in addition to the respective portions of the belt-shaped rubber 1 facing the thin-walled portions 9. Thus, here, it is possible to sufficiently prevent various delaminations, rubber chipping, and the like from occurring in the vulcanized joint portion, and it is possible to effectively prevent the occurrence of bears. In FIG. 2, reference numeral 14 denotes a hot air or other heat medium jacket or heater provided in the mold.

Here, when the thin portions 9 of the band-shaped rubber 1 are vulcanized and joined in this manner, the added volume of the two thin portions 9 must be larger than the cavity volume of the corresponding portion of the endless vulcanization mold 10. In order to prevent the cavity internal pressure from excessively increasing due to, for example, as shown in FIG. 3, the split surface of one of the molds is shown in plan view on the split surface of the endless vulcanization molding die 10. Corresponding cavity part 1
A rubber escaping portion 16 having a radius of about 2.5 to 5φ is provided, which makes it easier for excess rubber to flow in from 5. Here, as shown in FIGS. 3 (a) and 3 (b), the planar shape of the rubber escape portion 16 can be substantially L-shaped, T-shaped, or the like. In connection with the required flow resistance or the like to be exerted, it can be appropriately selected together with the dimensions.

Therefore, surplus rubber in the cavity of the endless vulcanization molding die 10 is removed from the rubber escape portion 1.
6, the internal pressure of the cavity is prevented from excessively increasing, and the deformation of the reinforcing cord 8 such as waving in the width direction or the thickness direction of the rubber track can be effectively suppressed. As a result, the occurrence of waves and the like on the rubber track and the change in pitch length at the endless joint are sufficiently prevented.

Here, as shown in FIG. 4, for example, as shown in FIG. 4, the rubber escape portion 16 is formed by forming a pair of dies with small holes penetrating in the thickness direction of the pair of dies. Alternatively, it may be constituted by at least one small hole penetrating only one mold. In this case as well, the formation position, the extending form, the size, and the like of the small holes can be appropriately selected as required.

FIG. 5 is a sectional view showing a vulcanization mold used for carrying out another method according to the present invention. This is because rubber strips 1a, 1b, 1c,... Which are sequentially added to a belt-shaped rubber 1 in which a reinforcing cord 8 is embedded are sequentially added based on repeated vulcanization molding of a vulcanization molding die a plurality of times. In this case, it is assumed that the rubber blocks are sequentially added to the left side of the figure.

This vulcanization mold having an upper mold 21 and a lower mold 22 is provided at the left end of the mold cavity 23 in the drawing.
A range corresponding to a molding region for one pitch of the belt-shaped rubber 1 is defined as a non-vulcanized molding region 25 provided with a water jacket 24, and the volume of the molding region for one pitch of the molding cavity 23 is changed to another region. It is increased in the range from more than 100% to 120% or less of the volume of the molding area for one pitch in the vulcanization molding area 26.

In this vulcanization mold, when the rubber block 1c is vulcanized under the action of the mold, one pitch of the left end portion of the rubber block 1c is molded in an unvulcanized or semi-vulcanized state. At the same time, the volume is larger than the required volume after vulcanization molding. So here,
In the subsequent vulcanization molding of the rubber block, one pitch of the left end portion of the rubber block 1c is shaded on the right end portion of the vulcanization molding area 26 of the vulcanization mold in the figure. The vulcanization molding of the next rubber block is performed with the position determined and arranged as shown in FIG.

According to this, the left end portion of the previously vulcanized rubber block 1c is greatly pressurized at the time of vulcanization molding of the next rubber block, whereby the rubber is smoothly plastically flowed. At the same time, the crosslinking reaction is performed quickly and sufficiently, so that the rubber block 1c is firmly adhered to the rubber block to be vulcanized and molded. Peeling, chipping of rubber, occurrence of bear, and the like are effectively prevented.

In the figure, the rubber block 1a to be vulcanized first is also equivalent to, for example, one pitch of the belt-like rubber 1 at the right end of the vulcanization mold. With a range of non-vulcanized molding areas,
It is preferable to use a cavity part volume in the non-vulcanization molding area which is larger than a similar cavity part volume in the vulcanization molding area 26. In the case where the end of 1a is directly vulcanized and joined to the rear end of a rubber block to be finally vulcanized and formed under a butt shape or the like to form an endless structure, both butt ends are sufficiently vulcanized. By pressing and sufficiently reacting, a strong endless joint can be realized.

This means that the end portions of the rubber blocks formed by the first and last vulcanization moldings are arranged at the overlapping end portions of the reinforcing cord 8, for example, as shown in FIG. Indirect vulcanization bonding using an endless vulcanization molding die 29 with the interposition of an unvulcanized inner peripheral surface member 27 and an unvulcanized outer peripheral surface member 28, which has been molded or before molding, and The same applies to the case where both end portions of the belt-shaped rubber formed by the multiple vulcanization molding are joined endlessly as shown in FIG. 6, and the end portions of the respective rubber blocks are respectively unvulcanized members 27, 28, It will be firmly adhered to the reinforcing cord 8 and the like.

In these cases, unvulcanized molding was performed on the right end portion of the vulcanizing mold 21 shown in FIG. 5 and the left and right end portions of the endless vulcanizing mold 29 shown in FIG. The excess rubber is allowed to flow into the rubber escape portion 16 having the structure described with reference to FIG. 3 or FIG. It is possible to prevent the internal pressure from excessively increasing, and to provide the same operation and effect as described above.

FIG. 7 is a sectional view showing a vulcanization mold used for carrying out still another method according to the present invention. That is, the rubber blocks are sequentially formed along the reinforcing cords 8 and formed to be continuous with each other by a plurality of feed vulcanization moldings in a state where the reinforcing cords 8 are endlessly configured in advance. It is used in the case.

Here, the vulcanization mold for the rubber block to be vulcanized first is as shown in FIG.
At both ends, a non-vulcanized molding zone 31 having a water jacket 30 formed therebetween, and a vulcanized molding zone 32 therebetween.
, Each of the non-vulcanized molding area 31,
The volume per unit length of the cavity portion, for example, the volume per length corresponding to one pitch of the rubber block is larger than the similar volume of the vulcanization molding area 32.

Accordingly, the rubber block 33 which is vulcanized and formed by this vulcanization mold is formed by unvulcanized or semi-vulcanized portions corresponding to one pitch on both right and left ends in the figure.
The portion corresponding to one pitch has a required volume after vulcanization molding, in other words, a volume larger than the volume of the portion corresponding to one pitch in the vulcanization molding region 32.

In such a vulcanization molding die, as shown in FIG. 8, one end of the vulcanization molding die is allowed to penetrate the reinforcing cord 8, but the rubber material in the cavity is leaked during the pressure molding. It is preferable to provide the lip 34 for preventing the rubber material from being provided with excellent formability and fluidity of the rubber material under a high pressing force, and also to improve the material yield.

FIG. 7B shows a vulcanization mold for forming the second and subsequent rubber blocks.
Only the left end of the figure is the non-vulcanized molding area 35,
The volume of the cavity portion in the non-vulcanization molding region is increased as described above, while the remaining portion including the right end portion in the figure is the vulcanization molding region 36. Therefore, the cavity portion corresponding to the right end portion of the drawing has a volume per unit length substantially the same as the volume per unit length of the cavity portion corresponding to the other vulcanization molding zone portions.

In the case where the second rubber block is vulcanized by such a vulcanization mold, the left end portion in the figure of the rubber block 33 formed by the first vulcanization molding is shown in FIG. As shown by hatching, the vulcanization molding die is positioned at the right end, and the second rubber block is vulcanized.

According to this, the left end portion of the rubber block 33 formed first is pressed against the constituent parts of the rubber block 33 and the second rubber block with a large force under the action of a large pressing force. At the same time, the flow smoothly flows to the details of the cavities, and furthermore, the cross-linking reaction at the left end portion proceeds promptly and sufficiently, similar to that of the second rubber block.
The rubber block is firmly adhered to the second rubber block, so that there is no inconvenience such as delamination or rubber chipping at the joint portion between the two rubber blocks, and no bear is generated.

By the way, the thus formed second
A large volume of unvulcanized or semi-vulcanized part is formed at the left end of the second rubber block 37 under the action of the non-vulcanized molding area 35. The third and subsequent rubber blocks can be formed in the same manner as described above, and as a result, the adjacent rubber blocks are firmly connected to each other.

Incidentally, even in this vulcanization molding die,
By providing the lip 34 as described above at the end on the side of the non-vulcanized molding area, the moldability, fluidity, leakage resistance, and the like of the rubber material can be improved.

FIG. 7 (c) shows a vulcanization mold for forming the final rubber block and using the rubber block as an endless structure. Each of the left and right end portions has a cavity partial volume substantially equal to the other portions, similarly to the right end portion of the vulcanization mold shown in FIG. 7 (b).

According to such a vulcanization mold, a large-volume unvulcanized end portion of the rubber block formed by the previous vulcanization molding is attached to the right end portion of the vulcanization mold diagram. In addition, by performing vulcanization molding of the last rubber block in a state where similar large-volume unvulcanized end portions and the like of the rubber block 33 formed first are respectively positioned and arranged at the left end portion in the figure, The rubber block formed first and the rubber block formed first can be firmly connected to the last rubber block for the same reason as described above.

In these vulcanization molds, the right end portion shown in FIG. 7B and FIG.
In this case, excess rubber material is allowed to flow into the rubber escape portion at each of the cavity portions at the left and right end portions, so that the excessive increase in the internal pressure of the cavity portion can also be sufficiently prevented.

[0051]

As is apparent from the above description, according to the present invention, the contact side end portion of the belt-shaped rubber or the rubber block is vulcanized by molding each rubber block.
By molding in an unvulcanized or semi-vulcanized state, and increasing the volume of the end part by the required volume after vulcanization molding, the connecting side end part is firmly attached with high adhesion to the opposing side member etc. Since it can be joined, it is possible to sufficiently prevent the occurrence of peeling between rubbery materials, between rubbery material and the reinforcing cord, and the occurrence of chipping of rubber, and at the same time, the occurrence of bear on the molding surface. Can also be effectively prevented.

Further, in this case, in vulcanization molding of an unvulcanized large-volume part or the like, the excess volume of the end part or the like with respect to the cavity volume is made to flow into the rubber escape part relatively easily. It is possible to effectively prevent the occurrence of a wavy deformation of the rubber crawler, a change in pitch length, and the like due to an excessive increase in the internal pressure.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a vulcanization mold used for carrying out a method according to the present invention.

FIG. 2 is a sectional view showing an endless vulcanizing mold.

FIG. 3 is a plan view showing a rubber escape portion.

FIG. 4 is a cross-sectional view of a vulcanization mold showing a rubber escape portion.

FIG. 5 is a longitudinal sectional view showing an embodiment of a vulcanization mold.

FIG. 6 is a sectional view showing another endless vulcanization mold.

FIG. 7 is a longitudinal sectional view showing another embodiment of a vulcanization mold.

FIG. 8 is a cross-sectional view illustrating an end lip of a vulcanization mold;

FIG. 9 is a sectional view showing a conventional vulcanization mold and a joining mold.

FIG. 10 is a cross-sectional view showing another conventional vulcanization mold and a joining mold.

FIG. 11 is a sectional view showing another joining mold.

FIG. 12 is a cross-sectional view showing another conventional vulcanization molding die.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Belt rubber 1a, 1b, 1c, 33, 37 Rubber block 2,23 Mold cavity 3,21 Upper die 4,22 Lower die 5 Lug 6 Core metal 7 Volume reduction part 8 Reinforcement cord 9 Thin part 10,29 Endless vulcanization Molding mold 11, 24, 30 Water jacket 12, 25, 31, 35 Non-vulcanized molding area 13, 26, 32, 36, 38 Vulcanized molding area 14 Heat medium jacket 15 Cavity part 16 Rubber escape part 27 Unvulcanized Inner peripheral surface member 28 Unvulcanized outer peripheral member 34 Lip

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B29K 105: 24 B29L 29:00 F term (Reference) 4F202 AA45 AC02 AG05 AG16 AH04 AM32 AR14 CA27 CB12 CC03 CC05 CK85 4F203 AA45 AC02 AG05 AG16 AH04 AM32 AR14 DA11 DC01 DF01 DF15 DJ01 DL10 4F213 WA15 WA38 WA39 WA87 WB02 WB18 WC01 WF01 WK01

Claims (7)

[Claims] 1. A belt rubber in which a reinforcing cord is embedded is formed by one vulcanization molding, and both ends of the rubber band are overlapped and joined to manufacture a rubber crawler. While molding in a vulcanized or semi-vulcanized state, the added volume of both ends thereof is configured to be larger than the required volume after vulcanization bonding, and at the time of vulcanization bonding of the both ends, excess rubber at both ends is removed. A method of manufacturing a rubber crawler, comprising flowing the rubber into a rubber escape portion of a vulcanization mold. 2. A belt-like rubber having a reinforcing cord embedded therein is formed by one vulcanization molding, and both ends of the belt-like rubber are endlessly joined to produce a rubber crawler. While molding in a vulcanized or semi-vulcanized state, the volume of each end portion thereof is configured to be larger than a required volume after vulcanization molding, and at the time of vulcanization molding of each end portion, excess rubber of each end portion is removed. A method of manufacturing a rubber crawler, comprising flowing the rubber into a rubber escape portion of a vulcanization mold. 3. A belt-like rubber having a reinforcing cord embedded therein is constituted by a continuous body of rubber blocks sequentially added by a plurality of feed vulcanization moldings from one end to the other end. In manufacturing a rubber crawler by joining endlessly, the end of the rubber block that is first vulcanized and formed on the connection side to the rubber block that is subsequently vulcanized and molded is used during the previous vulcanization and molding. , While being molded in an unvulcanized or semi-vulcanized state, and configured to be larger than the required volume after vulcanization molding, and when adding a rubber block to the connection side end portion, excess rubber at the connection side end portion is removed. A method of manufacturing a rubber crawler, comprising flowing the rubber into a rubber escape portion of a vulcanization mold. 4. An endless joining side end portion of a rubber block to be vulcanized first and last is formed in an unvulcanized or semi-vulcanized state, and an added volume of both end portions is vulcanized. 4. The vulcanizing apparatus according to claim 3, wherein the volume is configured to be larger than a required volume after the joining, and at the time of the vulcanizing joining of the both end portions, surplus rubber at the both end portions is caused to flow into a rubber escape portion of a vulcanizing mold. Of manufacturing rubber crawlers. 5. An endless joining side end portion of a rubber block to be vulcanized and molded first and last is formed in an unvulcanized or semi-vulcanized state, and the volume of each end portion is vulcanized. 4. The vulcanizing device according to claim 3, wherein the volume is larger than a required volume after molding, and at the time of vulcanization molding of each end portion, surplus rubber at each end portion flows into a rubber escape portion of a vulcanization molding die. Of manufacturing rubber crawlers. 6. A rubber crawler comprising an endless rubber ring having a reinforcing cord embedded therein is constituted by an endless structure of a rubber block sequentially added by a plurality of feed vulcanization moldings. The end of the rubber block to be connected to the rubber block to be subsequently vulcanized is molded in an unvulcanized or semi-vulcanized state during the previous vulcanization molding, and A rubber crawler having a volume larger than a required volume, wherein, when a rubber block is added to an end portion on the connection side, excess rubber at the end portion on the connection side flows into a rubber escape portion of a vulcanization molding die. Manufacturing method. 7. The rubber block which is vulcanized and molded first.
The other end portion is formed in an unvulcanized or semi-vulcanized state, and is configured to have a volume larger than a required volume after vulcanization molding, and when the other end portion is vulcanized and formed, the other end portion is formed. 7. The method for producing a rubber crawler according to claim 6, wherein the excess rubber is allowed to flow into a rubber escape portion of a vulcanization molding die.