JP2006062347A - Method for manufacturing driving belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a driving belt in which a releasing agent is not dipped in a reinforcing cloth and a reinforcing cloth is not peeled off from a rubber sheet. <P>SOLUTION: An expanded rubber sheet 53 containing a reinforcing cloth which is molded in such a way that a ditch part 4 and a projection part 5 alternate with a reinforcing cloth 30 located in the inner part is installed in a mold having a ditch, and a core line 50 and a reinforcing cloth 30 overlie it, and at the starting part of winding the reinforcing cloth 30 on the expanded rubber sheet 53 a rubber plate 70 is inserted between the expanded rubber sheet 53 and the reinforcing cloth 30. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a transmission belt, which is a cogged belt, and more particularly, facilitates mounting of a reinforcing cloth on a grooved mold, prevents adhesion of a release agent to the reinforcing cloth, and reinforces the reinforcing cloth in a belt state. The present invention relates to a method for manufacturing a power transmission belt that can prevent peeling of the belt from the belt.

  2. Description of the Related Art Conventionally, in a drive system in the mechanical field for scooters or general industries, a belt-type transmission that suspends a transmission belt between a driving pulley and a driven pulley and changes the effective diameter of the pulley to change the speed is used. The power transmission belt used here has a cog portion in which a cog crest portion and a cog trough portion are alternately arranged on at least one of the compression rubber layer and the stretch rubber layer, and the core wire is placed in the adhesive rubber layer. Low-edge cogged belts such as a low-edge single cogged belt or a low-edge double cogged belt are known.

  As the method (1) of the manufacturing method of the low edge cogged belt, the outer reinforcing cloth, the rubber sheet of the stretched rubber layer, the core wire, the rubber sheet of the compressed rubber layer, and the inner reinforcing cloth, which are mounted on the molding die, are sequentially wound. A method for molding a rubber sheet of a compression rubber layer by shrinking an inner reinforcing cloth by pressure at the time of vulcanization after inserting a cylindrical mother mold having alternately projecting portions and groove portions. There is. (For example, disclosed in Patent Document 1)

  Also, as part (2), a cog pad is prepared by placing an unvulcanized rubber sheet on a flat grooved mold longer than the belt circumference prepared in advance, and heating and pressing with a press to mold it into a cog shape. To do. This cog pad is fitted into the projecting part and groove part of the cylindrical master mold mounted on the forming drum, and the cut surface of the cog pad is abutted and jointed. After wrapping from above, the molding was completed and the process was shifted to the vulcanization process. (For example, it is disclosed in Patent Document 2.)

  However, in both methods (1) and (2), the rubber sheet and the start of winding of the reinforcing cloth are in contact, the release agent is immersed in the reinforcing cloth from the rubber sheet side, and the rubber sheet and the reinforcing cloth are peeled off. There was a problem.

US Pat. No. 3,464,875 JP 2002-1691 A

  The problem to be solved is to solve the above problems and provide a method for manufacturing a transmission belt in which the release cloth does not detach from the rubber sheet without immersing the release agent in the reinforcement cloth during the manufacture of the transmission belt. To do.

  The invention according to claim 1 of the present invention has a cog portion in which a cog crest portion and a cog valley portion are alternately arranged on at least the compression rubber layer of the compression rubber layer and the stretch rubber layer, and the cord is formed of the compression rubber layer and the stretch rubber layer. In the method for manufacturing a transmission belt embedded in between, a grooved mold and a rubber sheet with a reinforcing cloth, which has grooves and protrusions alternately, and is molded so that the reinforcing cloth is located on the inner surface, are used as the grooved mold. A transmission belt manufacturing method for mounting a core wire and a reinforcing cloth on the rubber sheet, wherein a belt is sandwiched between the rubber sheet and the reinforcing cloth at a winding start portion of the reinforcing cloth on the rubber sheet It is in the manufacturing method.

  The invention according to claim 2 is the method for producing a transmission belt according to claim 1, wherein the composition of the rubber plate is substantially the same as that of the rubber sheet.

  In the method for manufacturing a transmission belt according to the present invention, a rubber sheet with a reinforcing cloth, which has grooves and protrusions alternately, and is molded so that the reinforcing cloth is located on the inner surface, is attached to the grooved mold, and from above A method of manufacturing a transmission belt in which a core wire and a reinforcing cloth are laminated, wherein the rubber sheet is sandwiched between the rubber sheet and the reinforcing cloth at a winding start portion of the reinforcing cloth on the rubber sheet. Therefore, the release agent is not immersed in the reinforcing cloth, and therefore the reinforcing cloth is not peeled off in the belt state.

  According to a second aspect of the present invention, since the rubber plate composition is substantially the same as that of the rubber sheet, the rubber plate after vulcanization molding of the belt is provided. Is integrated with the rubber sheet, and the rubber plate does not become a foreign substance, and the belt does not crack.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic view of a reinforcing cloth molding apparatus in a method for manufacturing a transmission belt according to the present invention, FIG. 2 shows a state in which the reinforcing cloth is started to be pressed into a groove portion in the reinforcing cloth molding process, and FIG. A state is shown in which the reinforcing cloth is pressed against the groove-shaped portion in the cloth molding process.

  In the reinforcing cloth molding apparatus A, a molding die 1 in which a cylindrical base 2 made of vulcanized rubber having alternately groove-like portions 4 and protruding portions 5 is mounted on a metal base die 3 having a perfectly circular cross section is provided. On the other hand, projecting teeth 12 provided on the bottom surface 11 of the pinion roll 10 at regular intervals are engaged with the grooves 4 of the molding die 1. The pinion roll 10 is rotatably attached to one end of a rod 13 and pivots like a seesaw around a shaft 15 by the operation of a cylinder 14 provided at the other end, and comes into contact with and separates from the molding die 1. The reinforcing cloth 30 wound to a predetermined thickness is sandwiched between the molding die 1 and the pinion roll 10 while being pulled out, and is sequentially molded while driving the molding die 1 to rotate the pinion roll 10 together.

  In the molding of the reinforcing cloth 30, a rubber adhesive, which is a rubber paste, is applied only to the projection 5 of the molding die 1 by spraying or brushing on the surface, and then the bonded or untreated reinforcing cloth 30 is pulled out. Then, it is placed on the surface of the protruding portion 5 provided in the molding die 1. After the pinion roll 10 is lowered and it is confirmed that the tooth portion 12 is in the groove-like portion 4 of the molding die 1, the molding die 1 is rotated and the reinforcing cloth 30 positioned on the front protruding portion 5a is pinned. Pressing on the bottom surface 11 of the roll, and subsequently engaging the tooth portion 12 of the pinion roll 10 with the groove-like portion 4 of the molding die 1 so that the tooth-tip surface 20 contacts the groove-like bottom surface 21 of the molding die 1. To deform. The pinion roll 10 rotates with the rotation of the molding die 1.

  Then, by pressing the reinforcing cloth 30 in the adjacent rear protrusion 5b with the bottom surface 11 of another adjacent pinion roll, the reinforcing cloth 30 can be completely stretched along one groove-like section 4 without stretching. The deformation is repeated in sequence, and the reinforcing cloth 30 is molded so as to be in close contact with the entire periphery of the molding die 1. In the case of the present embodiment, when one tooth portion 12 of the pinion roll 10 is in the groove-shaped portion 4 of the molding die 1, the tooth portions 12 of the other pinion rolls 10 do not press the reinforcing cloth 30. The reinforcing cloth 30 does not stretch or float. While repeating this, the entire surface of the molding die 1 is covered with 1 to 4 plies. Then, the end of the reinforcing cloth 30 is cut by a cutter and is attached to the molding die 1.

  The rubber adhesive used here is obtained by dissolving various rubber compounds in a solvent such as methyl ethyl ketone (MEK) and toluene and mixing them. Improve close contact.

  The reinforcing fabric 30 is made of cotton, polyester fiber, nylon or the like, and is a fabric woven in plain weave, twill weave, satin weave, etc., and may be a wide angle canvas in which the crossing angle between warp and weft is about 90 to 120 °. The reinforcing cloth 30 is subjected to RFL treatment, and then the rubber composition is subjected to fiction and coaching to obtain a canvas with rubber. The RFL liquid is obtained by mixing an initial condensate of resorcin and formaldehyde into a latex. Examples of the latex used here include chloroprene, styrene / butadiene / vinylpyridine terpolymer, hydrogenated nitrile, and NBR.

Subsequently, as shown in FIG. 4, an unvulcanized pre-formed rubber sheet 35 having a predetermined thickness that has been cut in advance in a thickness direction (usually referred to as a bevel cut) is used as described above. After the reinforcing cloth 30 is wound around the molding die 1 and the cut surface 36 is abutted, the surface of the cut surface 36 is lightly pressed with a pressure jig (not shown) and jointed, and then a heating press 37 is used. The joint portion 38 is formed by heating and pressurizing. The heating and pressing conditions are a temperature of 80 to 120 ° C., a surface pressure of 1 to ² kg / cm ² , and a time of 10 to 30 seconds. The joint is usually positioned at the groove 4 of the molding die 1. When the position of the joint comes to the projecting portion 5, the joint comes to the belt cog valley portion, so that cracking is likely to occur.

  The raw rubber of the compression rubber sheet 35 used here is natural rubber, butyl rubber, styrene-butadiene rubber, chloroprene rubber, ethylene / α-olefin rubber, alkylated chlorosulfanated polyethylene (ACSM), hydrogenated nitrile rubber ( H-NBR), a rubber material such as a mixed polymer of hydrogenated nitrile rubber and unsaturated carboxylic acid metal salt, or a mixture thereof is used.

  The compressed rubber sheet 35 is made of fibers such as aramid fiber, polyamide fiber, polyester fiber, cotton, etc. in the rubber, and the length of the fiber varies depending on the type of fiber, but short fibers of about 1 to 10 mm are used. About 3 to 5 mm for aramid fibers, about 5 to 10 mm for polyamide fibers, polyester fibers, and cotton are used. And the direction of the short fibers in the rubber layer is oriented within the range of 70 ° to 110 ° when most of the short fibers are oriented 90 ° to the longitudinal direction of the belt. It is desirable.

As shown in FIG. 5, a resin film having excellent heat resistance and releasability made of polymethylpentene or polyethylene terephthalate, which is an anti-adhesion material 40, is wound on and bonded to the surface of the compressed rubber sheet 35. The process proceeds to a molding process for the compressed rubber sheet 35.

  In the rubber sheet molding step, a vulcanization can can be used. As shown in FIG. 6, in this case, after covering a rubber jacket 41, which is a steam blocking material, on the outside of the anti-adhesion material 40, this is installed in a vulcanizing can, and the temperature is 160 to 180 ° C. and the external pressure is 0.8. Molding is performed at about -0.9 MPa only for about 5 to 10 minutes to form an unvulcanized compressed rubber layer 45 as shown in FIG. Even if it molds with a vulcanization can, the crack of the joint part 38 of the compression rubber layer 45 does not occur. Of course, the molding can be performed by heating and pressurizing the outside of the compressed rubber sheet 35 by using a pressure band, a press method or the like instead of the vulcanized can.

  FIG. 8 shows a state in which a belt molded body is produced on the surface of a molded rubber sheet for compression rubber. A molding die 1 is mounted on a molding machine (not shown), polyester fiber, aramid fiber, glass fiber, etc. Is wound around a spiral on the compression rubber layer 45, and then an adhesive rubber sheet 51 for forming an adhesive rubber layer, an elastic rubber sheet 53 for forming an elastic rubber layer, and an upper reinforcing cloth 54 are successively wound. Thus, the belt molded body 55 is produced. At this time, as shown in FIG. 9, the rubber plate 70 is placed between the stretched rubber sheet 53 and the reinforcing cloth 54. Then, the molding die 1 taken out from the molding machine is placed on a support base and a jacket (not shown) is inserted.

  The belt molded body 55 is transferred to a vulcanizing can and vulcanized by an ordinary method. After vulcanization, the jacket and then the cylindrical belt sleeve are extracted from the cylindrical master 2 of the molding die 1, and the belt sleeve is cut to a predetermined width to form a transmission belt 60 which is a cogged belt as shown in FIG. Make it.

  The stretched rubber sheet 53 uses the same rubber composition as the compressed rubber sheet 35, and the adhesive rubber sheet 51 is the same type as the compressed rubber sheet 35, and may include the above short fibers, but preferably does not. . Further, it is preferable that the rubber plate 70 uses at least the same rubber composition as the stretched rubber sheet 53.

  As shown in FIG. 10, the power transmission belt 60 has a cord 62 made of a cord such as polyester fiber, aramid fiber, glass fiber, etc. embedded in the adhesive rubber layer 61, and the upper and lower portions of the adhesive rubber layer 61 are reinforced. It has a stretched rubber layer 64 including a cloth 63 and a compressed rubber layer 65 including a reinforcing cloth 63 as well. The compression rubber layer 65 is provided with a cog portion 68 in which cog valley portions 66 and cog mountain portions 67 are alternately arranged along the longitudinal direction of the belt at a constant pitch. Of course, a cog portion can also be provided on the surface of the stretched rubber layer 64.

  The present invention can be applied to a manufacturing method of a cogged belt used as a transmission belt for snowmobiles, scooters, and general industries.

It is the schematic of the shaping | molding apparatus of the reinforcement cloth in the manufacturing method of the transmission belt which concerns on this invention. A state in which the reinforcing cloth is started to be pressed into the groove-shaped portion in the reinforcing cloth molding step is shown. In the step of molding the reinforcing cloth, the state in which the reinforcing cloth has been pressed onto the groove-like portion is shown. The process of winding the sheet | seat for compressed rubber around a shaping | molding die in the manufacturing method of this invention, and butt-joining the cut surface inclined in the thickness direction is shown. The process which wound the adhesion prevention material around the surface of the sheet | seat for compressed rubber in the manufacturing method of this invention is shown. In the production method of the present invention, a process is shown in which a compressed rubber sheet is heated and pressed so as to be in close contact with the projecting portion and groove portion of the molding die. The state which shape | molded the sheet | seat for compressed rubber in the manufacturing method of this invention is shown. The state which produced the belt molded object on the surface of the sheet | seat for compression rubber type | molded in the manufacturing method of this invention is shown. In the manufacturing method of this invention, it is the figure which showed the state installed by pinching | interposing a rubber plate between an expansion | extension rubber sheet and a reinforcement cloth. It is a partial front view of the cogged belt obtained in the manufacturing method of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Molding die 2 Cylindrical mother die 4 Groove part 5 Projection part 5a Front projection part 5b Back projection part 10 Pinion roll 11 Bottom face 12 Tooth part 30 Reinforcement cloth 35 Sheet for compression rubber 36 Cut surface 40 Adhesion prevention material 41 Jacket 45 Compressed rubber layer 50 Core wire 51 Adhesive rubber sheet 53 Stretch rubber sheet 55 Belt molded body 70 Rubber plate

Claims (2)

A transmission that has coggs and cog valleys alternately arranged in at least the compression rubber layer of the compression rubber layer and the stretch rubber layer, and the core wire is embedded between the compression rubber layer and the stretch rubber layer In the manufacturing method for the belt for
A transmission belt that has a grooved portion and a protruding portion alternately and is attached to a grooved mold with a rubber sheet containing a reinforcing fabric that is molded so that the reinforcing fabric is positioned on the inner surface. A method for producing a power transmission belt, comprising: sandwiching a rubber plate between the rubber sheet and the reinforcing cloth at a winding start portion of the reinforcing cloth on the rubber sheet. The method for manufacturing a transmission belt according to claim 1, wherein a composition of the rubber plate is substantially the same as that of the rubber sheet.

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