JP2001212886A - Method of manufacturing belt for power transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a belt for power transmission which reduces the number of working processes on the occasion of making the belt, while facilitating the work of peeling a matrix provided with projecting parts and recessed parts, after vulcanization, and increases the number of times of use of the matrix. SOLUTION: Regarding the method of manufacturing the belt for power transmission wherein the belt is formed by providing a cog part at least in one of a compressed rubber layer and an extended rubber layer and by embedding a core wire in an adhesive runner layer, a formed body 15 is prepared by laminating the extended rubber layer, the core wire and the compressed rubber layer sequentially on a mold. Then, the matrix constituted of a cog- shaped rubber layer 37 having the projecting part 35 and the recessed part 34 alternately at prescribed intervals along the circumferential direction is laminated integrally by vulcanization on the inside of a covering body of vulcanized rubber, and a cylindrical jacket 30 thus formed is inserted and disposed in a runner layer provided outside the formed body 15, and then vulcanized. In this way, the surface of the rubber layer is embossed by the matrix 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a power transmission belt, such as a low-edge single cog belt or a low-edge double cog belt in which the number of man-hours for manufacturing a belt is reduced and the number of uses of a matrix is increased. The present invention relates to a method for manufacturing a power transmission belt.

[0002]

2. Description of the Related Art A preform manufacturing method and a spancog manufacturing method are typical examples of a conventional method for manufacturing a low-edge cog belt in which a cog portion is provided on the outer peripheral surface of a formed body. In the preform manufacturing method, a flat mother die with a goku longer than the belt circumference is prepared in advance, and an unvulcanized rubber sheet is placed thereon, and heated and pressed by a press to produce a preformed body.
After winding the rubber layer and the core wire around the mold, the preform was wound from above and butt-jointed to complete the molding, and the process was shifted to the vulcanization step. The matrix with a goku used here had convex portions and concave portions alternately at predetermined intervals on the front surface, and the reinforcing canvas was laminated on the back surface.

In the spancog manufacturing method, for example, a reinforcing cloth, an unvulcanized rubber sheet, a core wire, and an unvulcanized rubber sheet are sequentially wound around a mold to form a molded body. A mold having a cog-like shape was placed on the molded body from above, and then a jacket was inserted from above and vulcanized to mold the surface of the rubber layer with the cogs provided on the mold. After vulcanization, the operator removed the molded article with the mother mold from the jacket and removed the mother mold.

[0004]

The preform manufacturing method is as follows.
Because the reinforcing cloth and unvulcanized rubber sheet are formed in advance,
Although an accurate cog portion is formed, there is a problem that the cost increases because a preform step is added. In addition, since the matrix was deformed due to the heat shrinkage of the reinforcing canvas during vulcanization, stable dimensions could not be ensured, so that it could not be reused and the master was used only once. Also,
It is necessary to remove the mother die after vulcanization, but in this case, since the mother die is thermally contracted and strongly adhered to the vulcanization sleeve, it was a very heavy labor for the operator.

[0005] In addition, in the spancog manufacturing method, as in the case of the preform manufacturing method, it is necessary to cover the master with a cog at the time of vulcanization and to remove the master after vulcanization. It was hard work. Moreover, since the canvas used as a reinforcing material shrinks by heat during vulcanization and does not secure stable dimensions, the number of uses of the matrix is limited to about 3 to 5 times. The unusable matrix was scrapped. Therefore, simplification of the operation of peeling off a mother die provided with a cog after vulcanization and increasing the number of uses of the mother die have been problems to be solved at an early stage.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and reduces the man-hours required for producing a belt and facilitates the operation of peeling off a matrix having a convex portion and a concave portion after vulcanization. It is another object of the present invention to provide a method for manufacturing a power transmission belt in which the number of uses of the matrix is increased.

[0007]

According to the first aspect of the present invention, a cog portion is arranged on at least one of the compression rubber layer and the extension rubber layer, and the cord is embedded in the adhesive rubber layer. In a method for manufacturing a power transmission belt formed as described above,
A molded body is formed by sequentially laminating an extended rubber layer, a core wire, and a compressed rubber layer on a mold, and a rubber layer provided outside of the molded body is provided with convex portions at predetermined intervals along a circumferential direction. After inserting and installing a cylindrical jacket formed by laminating and integrating a matrix formed of a cog-shaped rubber layer having concave portions alternately inside an outer cover made of vulcanized rubber, the matrix is vulcanized. In the method for manufacturing a power transmission belt for molding the surface of the rubber layer by the method, the cog-shaped rubber layer having a convex portion and a concave portion provided at predetermined intervals along the circumferential direction from the vulcanized rubber. The use of a jacket that is laminated and integrated inside the outer cover makes it easier to remove the mother mold with convex and concave parts after vulcanization, and uses a jacket without reinforcing canvas. Reduces heat shrinkage deformation during vulcanization of the matrix , You can increase the number of uses of the matrix, also man-hours can be reduced.

[0008] In the invention according to claim 2 of the present application, the tooth canvas is laminated on the surface of the cog-shaped rubber layer having the convex portions and the concave portions alternately at predetermined intervals along the circumferential direction. Accurate cogs can be formed in the rubber layer to promote air bleeding during molding of the surface.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a double cog belt according to the present invention will be described below. FIG. 1 is a diagram showing a method for producing a molded article constituting a compression rubber layer, a core wire, and an extension rubber layer on a mold in a method for producing a double cog belt. First, the mold 1 having the teeth 2 and the grooves 3 alternately is prepared. Further, one to several reinforcing cloths 5, an unvulcanized rubber sheet 6 to be a compressed rubber layer, and an unvulcanized rubber sheet 7 to be an adhesive rubber layer are laminated, and a flat portion in which teeth and grooves are alternately arranged. The cog pad 9 in which the cog part 8 is formed is formed by placing the cog pad 8 in a mold and applying pressure. Of course, in the present invention, instead of the mold 1 having the tooth portions 2 and the groove portions 3 alternately, it is also possible to use a mold equipped with an inner matrix having grooves at predetermined intervals along the circumferential direction. .

[0010] A mold 1 is mounted on a molding machine (not shown), and a cog pad 9 of a predetermined length is wound around the mold 1 around the mold 1 while the cog portion 8 of the cog pad is fitted into the groove 3 of the mold, and the ends are brought into contact. After that, the core wire 10 made of a cord of polyester fiber, aramid fiber, glass fiber or the like is spirally wound. On it, 0 to several reinforcing cloths 12
Then, a laminate of the unvulcanized rubber sheet 13 of the stretched rubber layer is wound to form a molded body 15.

The rubbers used as the compression rubber layer and the extension rubber layer are natural rubber, butyl rubber, styrene-butadiene rubber, chloroprene rubber, ethylene-propylene rubber, and rubber.
Le Kill of chlorosulfonated fan polyethylene, hydrogenated nitrile rubber, a single rubber material, such as mixed polymer of hydrogenated nitrile rubber and the unsaturated carboxylic acid metal salt, or mixtures thereof, such as para-aramid fibers (product name : Short fibers such as Twaron, Kevlar, Technora), nylon, polyester, vinylon, and cotton are oriented in the belt width direction. The amount of the short fiber is 5 to 40 parts by weight based on 100 parts by weight of the rubber. The above-mentioned short fibers may be included in the adhesive rubber layer, but are preferably not included.

The reinforcing cloths 5 and 12 are made of cotton, polyester fiber,
It may be a wide-angle canvas made of nylon or the like and woven in a plain weave, a twill weave, a satin weave, or the like, wherein the crossing angle between the warp and the weft is about 90 to 120 °. After the RFL treatment, the reinforcing cloths 5 and 12 are subjected to fiction coating of the rubber composition to obtain a canvas with rubber. The RFL solution is obtained by mixing a latex with an initial condensate of resorcinol and formalin, and the latex used here is chloroprene, styrene / butadiene / vinylpyridine terpolymer, hydrogenated nitrile, NBR, or the like.

According to the present invention, the mold 1 taken out of the molding machine is placed on the support 20. One or both of the side walls 16 of the mold 1 have a holding hole at the center as shown in FIG. 17, a locking hole 18 provided along the circumferential direction, and a small positioning projection 19 provided at a position away from the center.

On the other hand, as shown in FIG. 2, the support base 20 has a main projection 21 provided at the center, a locking hole 23 provided on a concentric circle centered on the main projection 21, and a center of the main projection. And a set of alignment projections 22 adjacent to the position away from the projection.

When the mold 1 is set on the support 20,
The holding hole 17 of the mold 1 is inserted into the main projection 21 provided on the support 20, and the positioning projection 19 of the mold 1 is fitted between the adjacent positioning projections 22 of the support 20, and the mold 1 is moved. Fix correctly on the support base 20.

The guide rod 25 is made of metal or synthetic resin, and has a stop portion 27 projecting vertically from one bent end portion 26, and a stop portion 28 having a straight and easily removable shape at the other end. ing. As shown in FIGS. 3 to 5, the plurality of guide rods 25 are provided with stopper portions 27 and 28 at both ends in a locking hole 18 provided in the mold 1 and a locking hole 23 provided in the support base 20.
Inserted into and fixed. At this time, the guide rod 25 is
5 in contact with or slightly away from the surface.

FIG. 6 shows that after the guide rod 25 is mounted on the surface of the molded body 15, the matrix 31 made of vulcanized rubber is covered with the outer cover 32.
The jacket 30 laminated and integrated inside the guide rod 25
Is shown along the line. That is, the jacket 30 is provided with the matrix 3 provided at predetermined intervals along the circumferential direction.
The first concave portion 34 is inserted while being fitted into the guide rod 25. The size of the cross section of the guide rod 25 is such that it is completely fitted into the concave portion 34 of the matrix 31 and is slightly smaller than the concave portion 34. The cross-sectional shape is circular, oval, square, or the like, and is not particularly limited.

Subsequently, all the guide bars 25 are removed.
Thereafter, the molded body 15 is set in a vulcanizing can. Vulcanization is carried out in the usual way. After vulcanization, the jacket 30 in which the matrix 31 is laminated and integrated, and then the cylindrical sleeve are extracted from the mold 1 and cut into a predetermined width to produce the double cog belt 40.

FIG. 8 is a perspective view of a double cog belt 40 obtained by the method of the present invention. Double cog belt 4
In the configuration of No. 0, the core wire 42 is embedded in the adhesive rubber layer 41, and an extension rubber layer 43 and a compression rubber layer 44 are provided above and below the adhesive rubber layer 41, respectively. The extension rubber layer 43 and the compression rubber layer 44 are provided with cogs 45 and 46 along the belt longitudinal direction at a constant pitch, respectively. In the belt of the present embodiment, the groove bottom of the cog portion 45 provided on the extension rubber layer 43 and the groove bottom of the cog portion 46 provided on the compression rubber layer 44 coincide with each other. Of course, in the method of the present invention, it is also possible to set so that the groove bottom of the cog portion 45 provided on the extension rubber layer 43 coincides with the top of the cog portion 46 provided on the compression rubber layer 44. Note that it is not always necessary to use the above-described guide bar 25.

When producing a single cog belt,
First, a mold having a flat surface is prepared. On this, one to several reinforcing cloths, an unvulcanized rubber sheet to be an extension rubber layer, and an unvulcanized rubber sheet to be an adhesive rubber layer are laminated, and a core wire is further formed. It is wound around a spiral, and an unvulcanized rubber sheet to be a compressed rubber layer and 0 to several reinforcing cloths are wound thereon to produce a molded article. This laminating method is completely opposite to the double cog belt 40.

Subsequently, the jacket 30 having the matrix 31 laminated and integrated inside the outer cover 32 is inserted into the molded body 15. Thereafter, this is set in a vulcanizing can and vulcanized. After vulcanization, the jacket 30 in which the matrix 31 is laminated and integrated, and then the cylindrical sleeve are extracted from the mold and cut into a predetermined width to produce a single cog belt.

As shown in FIGS. 6 and 7, the jacket 30 used here has a cog-forming rubber layer 37 having concave portions 34 and convex portions 35 provided at predetermined intervals along the circumferential direction.
31 having a surface covered with toothed canvas 36 for air release.
And an outer cover 32 made of vulcanized rubber surrounding the outside, and the mother die 31 and the outer cover 32 are laminated and integrated. A flange 3 for sealing the inside during vulcanization is provided at one edge of the jacket 30.
8 are provided.

The matrix 31 becomes a part of the jacket 30,
The surface having the concave portion 34 and the convex portion 35 is covered with the tooth canvas 36, and the back surface is protected by the thick outer cover 32,
The reinforcing canvas is not laminated as in the related art. For this reason,
The heat shrinkage deformation of the matrix 31 during vulcanization can be reduced and the number of times of use can be increased, and the operation of peeling off the matrix 31 after vulcanization becomes easy because the outer cover 32 is attached.

As the toothed canvas 36, warp (longitudinal direction)
6 nylon, 6.6 nylon, 4.6 nylon, 6
Polyamide fiber such as 10 nylon and 12 nylon, polyester fiber, polyvinyl alcohol, polyethylene,
It is a spun yarn such as a polypropylene filament yarn or cotton. The composition of this filament yarn is 3 to 25 monofilaments each having 10 to 50 deniers.
The warp is formed by giving a twist of 30 times / 10 cm in the S or Z direction. Alternatively, a multifilament yarn obtained by bundling 10 to 200 filaments of 1 to 6 denier aramid fibers or twisting the bundles can be used. On the other hand, the weft (circumferential direction) is a highly elastic yarn, and has a configuration in which, for example, a urethane elastic yarn, a crimped yarn of a polyamide fiber, a spun yarn, and the like are combined.
The toothed canvas 36 is a cloth woven in plain weave, twill weave, satin weave, or the like, and is not particularly limited.

In the tooth canvas 36, the RFL processing is not necessarily performed.
It is not necessary to perform an adhesive treatment such as an epoxy treatment, an isocyanate treatment, and a soaking treatment. This is to improve the air flow in the constituent yarns of the tooth portion canvas 36 and between the constituent yarns, and to improve the air leakage when the surface of the rubber layer is molded.

The rubber of the cog-forming rubber layer 37 and the outer cover 32 is also made of natural rubber, styrene-butadiene rubber, chloroprene rubber, alkylated chlorosulfanated polyethylene,
Hydrogenated nitrile rubber, a rubber material such as a mixed polymer of a hydrogenated nitrile rubber and an unsaturated metal carboxylate alone or a mixture thereof is not particularly limited, but these are homogenous rubber and have heat resistance. Rich ones are preferred.

As a method of manufacturing the jacket 30, for example, a sewing machine joint or a hot melt joint is provided on an engraving drum provided with grooves and teeth extending in the circumferential direction alternately along the circumferential direction. After covering a cylindrical toothed canvas and wrapping a rubber layer of a predetermined thickness to be the cog-forming rubber layer 37 thereon, a rubber layer of a predetermined thickness to be the outer cover 32 is further wrapped to form a molded body. After vulcanization by a usual method, the vulcanized molded body is released from the engraving drum to form a jacket 30.

[0028]

EXAMPLES Hereinafter, the effects of the present invention will be confirmed by more specific experimental examples. Example 1 210 denier warp made of 6.6 nylon and 6.6
A twill fabric consisting of weft yarns obtained by twisting 140 denier of nylon and 140 denier of 6.6 nylon is used as a miss join to form a cylindrical toothed canvas, which is covered with an engraving drum, and a cog forming rubber layer is formed thereon. A rubber layer made of SBR having a thickness of 5 mm was wound, and a rubber layer made of SBR having a thickness of 10 mm was further wound as an outer cover, and then vulcanized by a usual method to produce a jacket.

As the core wire, a 1,100 denier polyethylene terephthalate fiber was twisted 11.4 times / 10.
cm, the number of lower twists is 21.0 times / 10 cm, and the yarn is twisted in the upside down direction to form a 2 × 3 twist structure.
00 unprocessed code was prepared. Next, the untreated cord is pre-dip with an isocyanate-based adhesive, dried at about 170 to 180 ° C., immersed in an RFL solution,
Stretch heat setting was performed at 200 to 240 ° C. to obtain a treated cord.

Further, a plain woven canvas using a spun cotton yarn was used as the reinforcing cloth. After immersing these canvases in the RFL solution, they were heat-treated at 150 ° C. for 2 minutes to obtain treated canvases. Then, apply the rubber composition to these treated canvas
Coaching to make a canvas with rubber.

For the compression rubber layer and the extension rubber layer, a rubber composition composed of chloroprene rubber containing short fibers of aramid was used, and for the adhesive rubber layer, a rubber composition composed of chloroprene rubber containing no short fibers was used.

The cog pad is formed by laminating one reinforcing cloth, an unvulcanized rubber sheet of a compressed rubber layer and an unvulcanized rubber sheet of an adhesive rubber layer, and forming a flat mold having teeth and grooves alternately arranged. A cog pad having a cog portion formed thereon was formed by installing and pressing at 80 ° C.

After preparing these materials, a cog pad was wrapped around the inner matrix mounted on a flat mold, and a core, a flat stretched rubber layer, and a reinforcing cloth were sequentially wrapped to form a formed body. Subsequently, after the mold was set at a predetermined position on the support base, six guide rods were attached at regular intervals, and the jacket was inserted and set along the guide rods. After removing all the guide rods, the mold was placed in a vulcanizer and vulcanized to obtain a belt sleeve. The sleeve was cut into a V-shape by a cutter and finished into individual low edge double cog belts.

The obtained low edge double cog belt is
Upper width 36.5mm, thickness 16.5mm, length 1310m
m, depth of upper cog part 5.0 mm, depth of lower cog part 5.0
mm, the pitch of the upper and lower cogs was 10.7 mm, and the maximum displacement of the bottom of the cogs was 1.5 mm.

Using the above jacket, the vulcanization was continued 20 times to produce a belt sleeve. However, no heat shrinkage of the matrix constituting the jacket was observed, and the jacket could be used continuously.

Comparative Example 1 Using the same material as in Example 1, a cog pad was wound around an inner mold mounted on a flat mold, and a core, a flat stretched rubber layer, and a reinforcing cloth were sequentially wound around the molded body. Was prepared. Subsequently, after setting the mold at a predetermined position on the support base, six guide rods were mounted at regular intervals, and the matrix was inserted and set along the guide rods. After removing all the guide rods, the mold in which the jacket was inserted was placed in a vulcanizing can and vulcanized to obtain a belt sleeve. A belt sleeve was manufactured by using the above master and the jacket, and vulcanizing was continued 5 times, but the heat shrinkage of the mother during the vulcanization was severe, and using more than this would form a cog section accurately. Became difficult.

[0037]

As described above, according to the first aspect of the present invention, a molded article is formed by sequentially laminating an extension rubber layer, a core wire, and a compression rubber layer on a mold, and provided outside the molded article. A mother die consisting of a cog-shaped rubber layer having alternating convex and concave parts at predetermined intervals along the circumferential direction is laminated on the rubber layer by vulcanization inside the outer cover made of vulcanized rubber. A method for manufacturing a power transmission belt in which the surface of a rubber layer is shaped by a mother die by inserting and installing a formed cylindrical jacket, and vulcanizing the convex, provided at predetermined intervals along the circumferential direction. By using a jacket in which a matrix consisting of a cog-shaped rubber layer having a convex part and a concave part is laminated and integrated on an outer cover made of vulcanized rubber, a matrix having convex parts and concave parts after vulcanization is provided. Work is easy, and the jacket without reinforcing canvas exists. The thermal shrinkage deformation of the matrix during vulcanization is also reduced by the use, can increase the number of uses of the matrix, also it has the effect of also reducing the work man-hours.

In the invention according to claim 2 of the present application, the toothed canvas is laminated on the surface of the cog-shaped rubber layer having the convex portions and the concave portions alternately at predetermined intervals along the circumferential direction. In order to promote air bleeding during molding of the surface, there is an effect that an accurate cog portion can be formed in the rubber layer.

[Brief description of the drawings]

FIG. 1 is a view showing a method for producing a molded body on a mold in the production method of the present invention.

FIG. 2 is a sectional view of a support used in the manufacturing method of the present invention.

FIG. 3 is a perspective view showing a step of installing a mold on a support base in the present invention.

FIG. 4 is an enlarged view of a portion A in FIG.

FIG. 5 is an enlarged view of a portion B in FIG. 3;

FIG. 6 is a perspective view showing insertion of a jacket along a guide rod in the present invention.

FIG. 7 is a cross-sectional view of the jacket shown in FIG.

FIG. 8 is a perspective view of a double cog belt obtained by the method of the present invention.

[Explanation of symbols]

 Reference Signs List 15 molded body 25 guide rod 30 jacket 31 matrix 32 outer cover 34 concave portion 35 convex portion 36 toothed canvas 37 cog forming rubber layer 40 double cog belt 41 adhesive rubber layer 43 stretch rubber layer 44 compression rubber layer 45 cog portion 46 Cog part

Claims (2)

[Claims] 1. A method of manufacturing a power transmission belt formed by arranging a cog portion on at least one of a compression rubber layer and an extension rubber layer and embedding a core wire in an adhesive rubber layer.
A molded body is formed by sequentially laminating an extended rubber layer, a core wire, and a compressed rubber layer on a mold, and a rubber layer provided outside of the molded body is provided with convex portions at predetermined intervals along a circumferential direction. After inserting and installing a cylindrical jacket formed by laminating and integrating a matrix formed of a cog-shaped rubber layer having concave portions alternately inside an outer cover made of vulcanized rubber, the matrix is vulcanized. A method for manufacturing a power transmission belt, comprising: molding a surface of a rubber layer by using the method. 2. A toothed canvas is laminated on the surface of a cog-shaped rubber layer having convex portions and concave portions alternately at predetermined intervals along a circumferential direction, and air escape occurs when the surface of the rubber layer is molded. 2. The method for producing a power transmission belt according to claim 1, which promotes power transmission.