JP2016078322A - Transmission belt and production method of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a transmission belt where disturbance in the alignment of core wires is hardly caused.SOLUTION: A production method of a transmission belt comprises: a step performing the forming and vulcanization of an endless tensile body layer 111 buried with a core wire 112 extending in a longitudinal direction of the belt; a step performing the molding and vulcanization of a rubber member 121A for a compression rubber layer; and a step bonding a vulcanized tensile body layer 111 and a vulcanized rubber member 121A for the compression rubber layer interposing rubber 122A for bonding. The rubber 122A for bonding contains at least one of a thiazole-based vulcanization accelerator and an organic amine-based vulcanization accelerator.SELECTED DRAWING: Figure 9

Description

  The present disclosure relates to a transmission belt and a manufacturing method thereof.

  A power transmission belt used for power transmission generally has a tensile body layer in which a core wire is embedded along the belt length direction, and a rib portion extending in the belt length direction or a cog portion provided at a predetermined interval in the belt length direction. And a compression rubber layer provided.

  Ideally, the cores of the transmission belt are arranged at equal intervals on the same plane. The transmission belt is wound along the pulley and travels in a state of being pulled on a substantially straight line between the pulleys. When the cords are arranged in the same plane, tension is applied to the cords evenly at each position. However, when the arrangement of the cores in the belt thickness direction is disturbed, the following problem occurs. For example, if there is a part that is displaced in the outer circumferential direction on the core wire, if it is wound around a pulley so that the inner circumference side of the belt is in contact, that part is wound with a large radius of curvature, so it is pulled excessively It becomes a state. Further, when the belt is wound around the pulley so that the outer peripheral side of the belt is in contact, the portion is wound with a small radius of curvature, so that the belt is loosened.

  Further, when the core wire is embedded, if the base has a truncated cone shape, the core wire is wound on one side with a larger radius of curvature than on the other side. When the belt in such a state is attached to the pulley layout, a very strong tension is applied to the core wire on the side having a small radius of curvature, and the core wire is largely loosened on the side having a large radius of curvature.

  As described above, when the arrangement of the core wires in the thickness direction is disturbed and does not exist on the same plane, the tension is not evenly applied to the core wires, and the belt is distorted. As a result, the belt meanders and falls off the pulley. Moreover, there is a possibility that the core wire may be cut early in a portion where a strong tension is applied. When the core wire is cut, there arises a problem that the belt breaks from that point.

  Further, when the arrangement of the core wires in the belt width direction is disturbed and the width direction interval is uneven, the tension applied to the core wires is transmitted to the pulley through the rubber member, and becomes a force for pulling the pulley. For this reason, an excessive force is applied to the rubber member at the portion where the intervals between the core wires are dense, and the core wire and the rubber are peeled off and the rubber is cracked at an early stage.

  In order to avoid such an early breakage of the belt, it is desirable that the core wire is wound on the cylindrical mold at substantially equal intervals. In the case of a flat belt, such an ideal configuration can be realized relatively easily. However, in the case of a V-belt, a V-ribbed belt, or the like, unlike a flat belt, it is difficult to make the core wire an ideal state.

JP 2005-125742 A

  For example, Patent Document 1 describes the following V-belt manufacturing method. First, a back canvas and unvulcanized adhesive rubber are wound on a flexible jacket mounted on a cylindrical drum, and a core wire is spun on the back canvas. Thereafter, the unvulcanized compressed rubber sheet is sequentially wound endlessly to form an unvulcanized laminate. Thereafter, the jacket is expanded, the laminate is pressed against the outer mold having the V-shaped protrusions, and the unvulcanized compressed rubber sheet is vulcanized into a shape along the outer mold. In this method, even if the core wires are ideally wound in an unvulcanized state, the laminate is deformed when the jacket is expanded, and the core wires are aligned in the thickness direction in the width direction. It will be disturbed. Further, the laminated body is pressed against the outer mold having the V-shaped projections to deform the unvulcanized compressed rubber sheet. For this reason, the arrangement of the core wires under the unvulcanized compressed rubber sheet is disturbed.

  In the case of a wrapped belt, the following manufacturing method is also being studied. First, an unvulcanized compressed rubber sheet is wound on a cylindrical mold. Next, the core wire is wound at substantially equal intervals. Further, wrap an unvulcanized rubber sheet. Next, it is cut into a predetermined width to obtain an unvulcanized laminate. Subsequently, a part of the lower side of the laminate is cut out and a reinforcing cloth is wound. The laminated body around which the reinforcing cloth is wound is put into a mold and vulcanized and formed into the shape of a final transmission belt.

  When cutting unvulcanized rubber, the rubber is deformed by the cutting resistance of the blade. For this reason, it is difficult to cut the unvulcanized rubber at a predetermined angle of the V-belt. Therefore, the shape of the unvulcanized laminate is usually not the same as the shape of the mold. For this reason, rubber | gum will move when putting a laminated body in a metal mold | die. Thereby, the arrangement of the cores is disturbed.

  Even if the unvulcanized laminate can be cut into the same shape as the mold, the laminate will be bent many times in the process from arranging the core wires to pushing into the mold. The line order is disturbed.

  After laminating an unvulcanized rubber sheet and a core on a cylindrical mold, external pressure is applied as it is to vulcanize, cut into a V-shaped section and finished into a V-belt, or cut into a predetermined shape. There is also a method of finishing it into a V-ribbed belt. In this case, a multilayer unvulcanized rubber sheet is laminated on the core wire. For this reason, errors in the thickness of the unvulcanized rubber sheet are accumulated, and the thickness of the entire belt after vulcanization tends to be uneven. Therefore, the arrangement of the cores in the belt is disturbed.

  It is an object of the present disclosure to realize a transmission belt and a manufacturing method thereof that are less likely to cause disturbances in the core.

  One aspect of a method for manufacturing a transmission belt according to the present disclosure includes a step of molding and vulcanizing an endless tensile body layer in which a core wire extending in the belt length direction is embedded, molding of a rubber member for a compressed rubber layer, and A step of vulcanizing, and a step of adhering the vulcanized tensile layer and the vulcanized rubber member for the compressed rubber layer with an adhesive rubber interposed therebetween. It contains at least one of a vulcanization accelerator and an organic amine vulcanization accelerator.

  In one aspect of the method for manufacturing the transmission belt, in the bonding step, both end portions in the length direction of the rubber member for the compressed rubber layer may be bonded to each other.

  In one aspect of the method for manufacturing a transmission belt, a step of adhering both end portions in the length direction of the rubber member for the compressed rubber layer may be further provided before the step of adhering.

  In one aspect of the method for manufacturing the transmission belt, the tensile body layer and the rubber member for the compressed rubber layer may be vulcanized under different conditions.

  In one aspect of the method of manufacturing the transmission belt, the adhering step includes adhering the first rubber member for the compression rubber layer to the inner peripheral side of the tensile body layer, and the second compression rubber to the outer peripheral surface of the tensile body layer. It is good also as a process of adhering the layer rubber member.

  One aspect of the transmission belt of the present disclosure includes an endless tensile body layer in which a core wire extending in the belt length direction is embedded, a compression rubber layer bonded to the tensile body layer, a tensile body layer, and a compression rubber An adhesive rubber layer provided between the layers, and the adhesive rubber layer contains at least one of a thiazole vulcanization accelerator and an organic amine vulcanization accelerator.

  In one aspect of the transmission belt, the compression rubber layer has a bonding portion in which end portions in the belt length direction are bonded to each other.

  Another aspect of the transmission belt of the present disclosure is a transmission belt manufactured by the method of manufacturing the transmission belt of the present disclosure.

  According to the transmission belt and the manufacturing method thereof of the present disclosure, it is possible to easily manufacture the transmission belt without being disturbed in the arrangement of the core wires.

(A) And (b) is a figure which shows the power transmission belt which concerns on one Embodiment. (A) And (b) is a figure which shows 1 process of the manufacturing method of the transmission belt which concerns on one Embodiment, respectively. (A) And (b) is a figure which shows 1 process of the manufacturing method of the transmission belt which concerns on one Embodiment, respectively. It is sectional drawing which shows a tensile body layer. It is a figure which shows 1 process of the manufacturing method of a tensile body layer. It is sectional drawing which shows the modification of a tensile body layer. It is a figure which shows the funnel press used for manufacture of the rubber member for compression rubber layers. It is sectional drawing which shows the modification of the rubber member for compression rubber layers. (A) And (b) is a figure which shows 1 process of the modification of the manufacturing method of the transmission belt which concerns on one Embodiment, respectively. It is a figure which shows the modification of the manufacturing method of the power transmission belt which concerns on one Embodiment. (A)-(c) is a figure which shows the adhesion part of a compression rubber layer, respectively. (A) is a figure which shows the problem of the manufacturing method of the conventional V-ribbed belt, (b) is a figure which shows the V-ribbed belt manufactured by the method which concerns on one Embodiment. It is a figure which shows the modification of the manufacturing method of the power transmission belt which concerns on one Embodiment. It is sectional drawing which shows the modification of the power transmission belt which concerns on one Embodiment. It is a perspective view which shows the modification of the power transmission belt which concerns on one Embodiment.

  As shown in FIG. 1, the transmission belt of the present embodiment includes a tensile body layer 111 that is a layer in which a core wire 112 that is a tensile body is embedded, and a compressed rubber that is a layer having a transmission surface in contact with a pulley. Layer 121. As shown in FIGS. 2 and 3, the transmission belt of the present embodiment bonds the tensile body layer 111 and the rubber member 121 </ b> A for the compression rubber layer, which are each formed in advance and vulcanized, as a compression rubber layer. Can be formed. Specifically, it can be formed as follows.

<Tension layer>
As shown in FIG. 4, the tensile body layer 111 is an endless flat belt in which core wires 112 extending in the belt length direction and spirally arranged so as to have a predetermined pitch in the belt width direction are embedded. Shape. FIG. 4 shows an example in which the tensile body layer 111 has an adhesive rubber layer 115 and a cover rubber layer 116. The cross section of the tensile layer 111 may be trapezoidal.

  An example of molding and vulcanization of the tensile layer 111 is shown below. As shown in FIG. 5, a first unvulcanized rubber sheet 213 to be a cover rubber layer 116 is wound around the outer peripheral surface of a cylindrical forming drum 211 having a smooth surface. Next, the second unvulcanized rubber sheet 214 to be the adhesive rubber layer 115 is wound. Next, the pretreated core wire 112 is spun at a constant pitch in a spiral shape. Further, a third unvulcanized rubber sheet 215 to be the adhesive rubber layer 115 is wound to produce a cylindrical laminate. The laminated body on the mold is covered with a rubber sleeve and then vulcanized. Thereby, a cylindrical slab is obtained, and the endless tensile layer 111 as shown in FIG.

  In this method, the core wire 112 is spun on the outer periphery of the cylindrical forming drum 211. For this reason, it is easy to arrange the core wires on the same plane and at equal intervals. In addition, no force is applied to deform the laminate between the spinning of the core 112 and the end of vulcanization. Therefore, there is no possibility that the arrangement of the core wires is disturbed in the thickness direction and the width direction of the tensile body layer 111 during molding. Therefore, it is possible to easily realize the tensile body layer 111 in which the core wires are arranged on the same plane and at equal intervals.

  For vulcanization of the laminated body, for example, the laminated body may be heated and pressurized in a vulcanizing can to integrate the laminated unvulcanized rubber sheets. The vulcanization temperature can be about 100 ° C. to 180 ° C., the pressure can be about 0.5 MPa to 2.0 MPa, and the time can be about 10 minutes to 60 minutes.

  The first to third unvulcanized rubber sheets 213 to 215 are produced, for example, by kneading a rubber compound with a predetermined composition using a kneader or a Banbury mixer, and then performing calendar molding or extrusion molding. can do. The thickness of the unvulcanized rubber sheet is not particularly limited, but can be about 0.1 mm to 1 mm.

  Examples of raw rubber components of the first to third unvulcanized rubber sheets 213 to 215 include natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, acrylonitrile butadiene rubber, hydrogenated acrylonitrile butadiene rubber, and butyl rubber. And ethylene-α-olefin elastomers such as chlorosulfonated polyethylene rubber, urethane rubber, ethylene propylene rubber, and ethylene propylene diene rubber (EPDM).

  The first to third unvulcanized rubber sheets 213 to 215 include, for example, a crosslinking agent (for example, sulfur, organic peroxide), an antioxidant, a processing aid, a plasticizer, a reinforcing material such as carbon black, In addition, a filler and the like can be blended. Short fibers may be blended in the first to third unvulcanized rubber sheets 213 to 215, but from the viewpoint of adhesiveness with the core wire, at least a second unvulcanized rubber layer that becomes an adhesive rubber layer The rubber sheet 214 and the third unvulcanized rubber sheet 215 are preferably not blended with short fibers.

  The second unvulcanized rubber sheet 214 and the third unvulcanized rubber sheet 215 may be the same or different in thickness and composition. The first unvulcanized rubber sheet 213, the second unvulcanized rubber sheet 214, and the third unvulcanized rubber sheet 215 may have the same or different thickness and composition. .

  The core 112 may be appropriately selected according to the required belt characteristics. For example, an organic fiber such as an aramid fiber, a polyester fiber, a polyamide fiber, or a rayon fiber, or an inorganic fiber such as a glass fiber or steel that is bound in a cord shape can be used.

  The pretreatment of the core wire 112 may be performed, for example, by immersing the core wire in a resorcin-formalin-latex (RFL) treatment liquid and baking it, and then immersing in a rubber paste as necessary to heat-dry. The immersion and baking in the RFL treatment liquid can be repeated a plurality of times as necessary. The rubber paste can be obtained by dissolving the same rubber as that used in the rubber compound constituting the adhesive rubber layer in toluene or the like.

  The tensile body layer 111 is not limited to the above method and may be molded and vulcanized as long as the core wires 112 can be arranged on the same plane and at equal intervals. In addition, as shown in FIG. 6, the canvas 114 may be vulcanized and bonded to the back surface of the tensile body layer 111.

<Rubber member for compression rubber layer>
An example of molding and vulcanization of the rubber member 121A for the compressed rubber layer that becomes the compressed rubber layer 121 is shown below. First, a rubber compound kneaded with a predetermined composition is supplied into a rubber extruder in the form of pellets or ribbons. An unvulcanized rubber member having a target shape is continuously extruded using a die corresponding to the cross-sectional shape of the rubber member 121A for the compressed rubber layer. Next, this unvulcanized rubber member is vulcanized. As a result, an open-end rubber member 121A for the compressed rubber layer is obtained.

  The vulcanization of the unvulcanized rubber member can be performed by, for example, an apparatus (rotor press) as shown in FIG. In FIG. 7, in the circumferential direction of the outer peripheral surface of the metal drum 232, a groove having a shape that just fits the unvulcanized rubber member 251 is formed. The unvulcanized rubber member 251 is continuously supplied to the groove of the metal drum 232. An unvulcanized rubber member 251 is sandwiched by a steel band 240 spanned between a metal drum 232 and a pulley 233, and continuously press vulcanized at a predetermined temperature and pressure. The vulcanization temperature can be about 100 ° C. to 180 ° C., the molding pressure can be about 0.5 MPa to 2.0 MPa, and the vulcanization time can be about 10 minutes to 60 minutes, for example.

  The rubber member 121A for the compressed rubber layer may have a composition according to the required belt characteristics. Examples of raw rubber components include natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, acrylonitrile butadiene rubber, hydrogenated acrylonitrile butadiene rubber, butyl rubber, chlorosulfonated polyethylene rubber, urethane rubber, ethylene propylene rubber, and ethylene. Ethylene-α-olefin elastomers such as propylene diene rubber (EPDM) can be used. As a compounding agent, for example, a crosslinking agent (for example, sulfur, organic peroxide), an anti-aging agent, a processing aid, a plasticizer, a reinforcing material such as carbon black, a filler, a short fiber, and the like can be used.

  Examples of the short fibers blended in the rubber compound used for the rubber member 121A for the compressed rubber layer include polyamide short fibers, vinylon short fibers, aramid short fibers, polyester short fibers, and cotton short fibers. The short fiber has a length of 0.2 to 5.0 mm and a fiber diameter of 10 to 50 μm, for example. The short fiber may be produced by, for example, cutting a long fiber that has been subjected to an adhesive treatment to be heated after being immersed in an RFL aqueous solution or the like into a predetermined length along the length direction. The short fibers may be blended as necessary, and may not be blended. Even when the rubber member 121A for the compressed rubber layer is extruded, the short fibers can be oriented in the required direction by adjusting the amount of short fibers.

  By compressing and continuously vulcanizing the rubber member 121A for the compressed rubber layer, the rubber member 121A for the compressed rubber layer having a uniform shape and characteristics can be easily obtained. However, it may be vulcanized by other methods. For example, the unvulcanized rubber member may be pre-cut to a predetermined length and then vulcanized by a normal flat press. Moreover, you may form the rubber member 121A for compression rubber layers by methods other than extrusion molding. As shown in FIG. 8, the canvas 124 may be bonded to the surface of the rubber member 121A for the compressed rubber layer.

  Although an example of forming the rubber member 121A for the open end compression rubber layer has been shown, when the open end unvulcanized rubber member is vulcanized, the end portions in the length direction are vulcanized and bonded, and the vulcanization is completed. It is also possible to make it endless in the state. Alternatively, the rubber member 121A for the compressed rubber layer can be formed by molding and vulcanizing into an endless shape in advance.

<Adhesion between tensile body layer and rubber member for compression rubber layer>
By adhering the tensile body layer 111 and the rubber member 121A for the compressed rubber layer, a transmission belt having the tensile body layer 111 and the compressed rubber layer 121 is obtained. Adhesion between the tensile body layer 111 and the rubber member 121A for the compressed rubber layer can be performed using an adhesive rubber as follows.

  As shown in FIGS. 9A and 9B, the unvulcanized adhesive rubber sheet 122A is disposed between the tensile body layer 111 and the rubber member 121A for the compressed rubber layer, and is bonded to the sheet. 122A is vulcanized. Thereby, the tensile body layer 111 and the rubber member 121 </ b> A for the compressed rubber layer are bonded through the bonding rubber layer 122. The vulcanization temperature can be a room temperature to about 180 ° C. The vulcanization time may be an optimum time according to the vulcanization temperature. For example, the vulcanization time can be about 5 minutes at a temperature of about 170 ° C. Further, a vulcanization time of about 24 hours at a temperature of about 60 ° C. can be used. The pressure at the time of vulcanization may be selected as appropriate, and can be, for example, about 1 MPa.

  The adhesive rubber contains at least one of a thiazole vulcanization accelerator and an organic amine vulcanization accelerator. By including both a thiazole vulcanization accelerator and an organic amine vulcanization accelerator, the adhesion function is improved, but a thiazole vulcanization accelerator or an organic amine vulcanization accelerator may be used alone. .

  By including a thiazole vulcanization accelerator or an organic amine vulcanization accelerator, adhesion under a low temperature condition of about 60 ° C. or adhesion under a short time condition of about 170 minutes at 170 ° C. becomes possible. High accuracy by significantly suppressing deterioration and dimensional change of the core wire of the tensile body layer and vulcanized rubber of the tensile body layer and the compressed rubber layer by bonding at low temperature or in a short time In addition, it is possible to produce a belt having a long life.

  Examples of thiazole vulcanization accelerators include 2-mercaptobenzothiazole (MBT), dibenzothiazyl disulfide (MBTS), sodium salt of 2-mercaptobenzothiazole, zinc salt, copper salt, cyclohexylamine salt, 2- ( 2,4-Dinitrophenyl) mercaptobenzothiazole, 2- (morpholinodithio) benzothiazole, 2- (2,6-diethyl-4-morpholinothio) benzothiazole, and the like can be used. These may be used alone or in combination. Among these, cyclohexylamine salt of 2-mercaptobenzothiazole (for example, trade name M-60-OT manufactured by Ouchi Shinsei Chemical Co., Ltd.) is preferable.

  The organic amine vulcanization accelerator may be hexamethylenetetramine, cyclohexylamine, n-butyraldehydeaniline, octylamine, and higher aliphatic amines such as dodecylamine (laurylamine) or octadecylamine (stearylamine). it can. These may be used alone or in combination. Of these, dodecylamine is preferable.

  The adhesive rubber may contain a vulcanization accelerator other than the thiazole vulcanization accelerator and the organic amine vulcanization accelerator. However, other vulcanization accelerators may not be included as long as at least one of a thiazole vulcanization accelerator and an organic amine vulcanization accelerator is included. Examples of vulcanization accelerators other than thiazole vulcanization accelerators and organic amine vulcanization accelerators include guanidine compounds, thiuram compounds, dithiocarbamate compounds, thiourea compounds, sulfenamide compounds, xanthate compounds, poly-p. -Dinitrosibenzene, N, N'-m-phenylene dimaleimide and the like.

  What is necessary is just to select suitably the other composition of the rubber | gum for adhesion | attachment according to the composition of the tensile body layer 111 and the rubber member 121A for compression rubber layers. For example, the main rubbers include natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, acrylonitrile butadiene rubber, hydrogenated acrylonitrile butadiene rubber, butyl rubber, chlorosulfonated polyethylene rubber, urethane rubber, and ethylene propylene rubber. Further, ethylene-α-olefin elastomers such as ethylene propylene diene rubber (EPDM), and latexes thereof can be used. These may be used alone or in combination of two or more.

  Compounding agents such as a vulcanizing agent, a reinforcing material, a filler, a plasticizer (softener), an anti-aging agent, and a processing aid may be added to the adhesive rubber.

  The vulcanizing agent is not particularly limited, and a general rubber vulcanizing agent can be used. For example, a sulfur type crosslinking agent, an organic peroxide crosslinking agent, a metal oxide, a quinone dioxime compound, an isocyanate compound, a nitrile oxide compound, and the like can be given. These may be used alone or in combination of two or more.

  As the reinforcing material, known materials such as carbon black, silica, and short fibers can be used. Known materials can also be used for the filler, plasticizer, anti-aging agent, processing aid, and other compounding agents.

  The adhesive rubber is kneaded using a kneader or a banbury mixer after a rubber compound of a predetermined composition, and then calendered or extruded to form a sheet 122A having a thickness of about 0.1 mm to 1 mm. That's fine.

  The adhesive rubber may be applied to at least one surface of the tensile body layer 111 and the rubber member 121A for the compressed rubber layer as a liquid instead of being formed into a sheet and disposed on the adhesive surface. Liquid adhesive rubber is prepared by, for example, dissolving or dispersing a rubber compound for adhesive rubber in an organic solvent such as aliphatic and alicyclic hydrocarbons, aromatic compounds, and alcohol, water, and a mixture thereof. What is necessary is just to prepare. By applying a liquid adhesive rubber and evaporating the solvent or dispersion medium, the tensile body layer 111 and the rubber member 121A for the compression rubber layer are pressure-bonded, and a predetermined temperature of about room temperature to 180 ° C. is applied. Adhesive. In this case, the adhesive rubber layer 122 can be very thin and may not be observed.

  Also, a sheet-like adhesive rubber and a liquid adhesive rubber can be used in combination. For example, a liquid adhesive rubber is applied to at least one surface of the tensile body layer 111 and the rubber member 121A for the compressed rubber layer, and further, a sheet-like material is formed between the tensile body layer 111 and the rubber member 121A for the compressed rubber layer. It is also possible to bond the tensile layer 111 and the rubber member 121A for the compressed rubber layer by pressing and vulcanizing by pressing the adhesive rubber.

  When the tensile body layer 111 and the rubber member 121A for compressed rubber layer are bonded together, surface treatment may be performed on at least one surface of the tensile body layer 111 and the rubber member 121A for compressed rubber layer. For example, plasma treatment, corona treatment, ultraviolet irradiation, mechanical buffing, or the like can be performed. Surface treatment using a dicarboxylic acid solution can also be performed. These surface treatments may be used alone or in combination.

  Adhesion between the tensile body layer and the rubber member for the compressed rubber layer can be performed after cutting to a predetermined width by cutting or the like, but after bonding the wide tensile body layer and the rubber member for the compressed rubber layer , It may be cut to have a predetermined width.

<Adhesion of both ends of rubber member for compression rubber layer>
When the vulcanized compression rubber layer rubber member 121A is formed in an open-end string shape, both end portions in the length direction of the compression rubber layer rubber member 121A are bonded to form an endless shape.

  Bonding of both end portions of the rubber member 121A for the compressed rubber layer may be performed by using an adhesive rubber in the same manner as the bonding of the tensile body layer 111 and the rubber member 121A for the compressed rubber layer. The adhesive rubber may be formed into a sheet and disposed on the adhesive surface, or may be applied to the adhesive surface as a solution or a dispersion.

  Bonding of both ends of the rubber member 121A for the compressed rubber layer is performed in the same process as the bonding of the tensile body layer 111 and the rubber member 121A for the compressed rubber layer, as shown in FIGS. Can do. However, as shown in FIG. 10, the compression rubber layer rubber member 121 </ b> A, which is formed before the bonding between the tensile body layer 111 and the compression rubber layer rubber member 121 </ b> A, is formed into an endless body layer 111. It may be glued. When the rubber member 121A for compressed rubber layer is endless in a vulcanized state, it is not necessary to perform a step of bonding both end portions in the length direction of the rubber member 121A for compressed rubber layer.

  Even when both end portions of the rubber member 121A for the compressed rubber layer are bonded, a surface treatment can be performed on the bonding surface. For example, plasma treatment, corona treatment, ultraviolet irradiation, mechanical buffing, or the like can be performed. Surface treatment using a dicarboxylic acid solution can also be performed. These surface treatments may be used alone or in combination.

  In the case where both ends of the compression rubber layer rubber member 121A are bonded to each other before bonding the tensile body layer 111 and the compression rubber layer rubber member 121A to form an endless shape, a free radical initiator or an adhesive is used. May be used for bonding.

As the free radical initiator, a halogen-donor compound such as lichloroisocyanuric acid or an organic peroxide can be used. Examples of the halogen-donor compound and the organic peroxide include glycoluril chloramine, 1,3-dichloro-5,5-dimethylhydantoin, and 1,3,5-trichloro-2 described in JP-A-63-86730. , 4-dioxohexahydrotriazine, N-bromosuccinimide, N-chlorosuccinimide, cyanamide derivatives, N-chloroamino condensation products, dichloroisocyanuric acid, trichloroisocyanuric acid, and N-chlorosulfonamide. Examples of the N-chloroamino condensation product include dichloroazodicarbonamidine and N-chloromelamine. Examples of N-chlorosulfonamide and related compounds include halogen-donor compounds such as chloramine-T and organic peroxides such as peroxide or hydroperoxide. The organic peroxide, such as di - tert-butyl peroxide, tert-butyl cumyl dimethylsulfoxide, dicumyl peroxide, alpha, alpha ^'- bis (tert-butylperoxy)-p-diisopropylbenzene, 2,5-dimethyl -2,5-di- (tert-butylperoxy) hexane, 2,5-dimethyldi- (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, tert-butylperoxy- Examples thereof include isopropyl carbonate and 1,1-bis (tert-butylperoxy) -3,5,5-trimethylcyclohexane.

  Examples of the adhesive include a polyurea-based adhesive (see, for example, Japanese Patent Application Publication No. 2010-507689) and an adhesive containing a silane coupling agent (see, for example, JP-A-9-240217). ), Acrylic-modified silicone resin, room temperature moisture-curing elastic adhesive (for example, Super X series marketed by Cemedine Co., Ltd.), polyurethane adhesive (for example, J Adhes VOL.50 No.1 Page.25-42 (See May 1995)), an adhesive containing an epoxy compound, an adhesive made of a polymer of (meth) acrylic acid alkyl ester having a hydrolyzable silicon-containing group, and an adhesive made of an isocyanate-containing rubber compound (See, for example, Japanese Patent Application Laid-Open No. 2001-316656) and the like.

  Examples of polymers of (meth) acrylic acid alkyl esters having hydrolyzable silicon-containing groups include SMAP (Kaneka Telechelic Polyacrylate) SA100S, SA110S, SA120 and SA200SX, and Kaneka MS Polymer manufactured by Kaneka Chemical Industry Co., Ltd. S943 etc. can be mentioned. The adhesive mainly composed of these polymers may contain other components. For example, at least one of carbon black, silica, and calcium carbonate may be included. Moreover, the silane coupling agent may be included. It may contain at least one of general curing agents, fillers, plasticizers, softeners, thixotropic agents, anti-aging agents, antistatic agents, and adhesive agents.

As an adhesive comprising an isocyanate-containing rubber compound, a rubber compound containing isocyanate can be dissolved in a solvent and used. It does not specifically limit as a solvent, For example, hydrocarbons, chlorinated hydrocarbons, ketones, esters, etc. can be mentioned. Considering the influence of humidity, it is preferable that the compatibility with water is small. In order to make it less susceptible to humidity and temperature, the solvent SP value is more preferably 18.4 ([J / cm ³ ] ^1/2 ) or less. Examples of the compound having an SP value of 18.4 ([J / cm ³ ] ^1/2 ) or less include n-hexane, toluene, cyclohexane, xylene, ethyl acetate, mineral spirit, petroleum ether, and ethyl ether. Can be mentioned. These may be used alone or in combination of two or more.

  The rubber compounding agent may be mix | blended with the rubber compound containing isocyanate. The rubber compounding agent is not particularly limited. For example, reinforcing agents or fillers such as carbon black, calcium carbonate, silica, clay, and talc, t-butylphenol resin, coumarone resin, terpene / phenol resin, rosin derivative, and petroleum Examples thereof include tackifiers such as a series hydrocarbon resin, anti-aging agents such as N-phenyl-N′-isopropyl-p-phenylenediamine, and vulcanizing agents such as MgO, ZnO, and PbO.

  When the open-end rubber member 121A for the compression rubber layer is used in the manufacture of the transmission belt of the present embodiment, an adhesive portion 121a may be recognized on the compression rubber layer 121 as shown in FIG. . Both end portions in the length direction of the rubber member 121A for the compressed rubber layer may be any shape as long as they can be bonded, but can be formed to be obliquely cut so as to coincide with each other. In this case, as shown to Fig.11 (a), the adhesion part 121a of the compression rubber layer 121 becomes diagonal with respect to the length direction of a transmission belt. As a result, it is possible to increase the bonding area and make it difficult to produce a step or the like at the bonding point. The joint angle θ of the bonding portion 121a is not limited, but may be 45 °, for example. Moreover, as shown in FIG.11 (b), it can also be set as the finger joint which provided the unevenness | corrugation which can be mutually fitted in both ends. In addition, when the rubber member 121A for the compressed rubber layer is bonded using the bonding rubber sheet, a vulcanized bonding rubber 123 is interposed as shown in FIG.

  As described above, the rubber member 121A for the compressed rubber layer may be molded and vulcanized in an endless state. In this case, a transmission belt can be obtained in which the adhesive rubber 121 is not recognized on the compressed rubber layer 121.

  As described above, the method of manufacturing the transmission belt according to the present embodiment includes a vulcanized tensile body layer 111 and a vulcanized rubber member 121A for a compressed rubber layer, and a thiazole vulcanization accelerator and an organic amine vulcanization agent. Bonding is performed using an adhesive rubber containing at least one of a sulfur accelerator. For this reason, unlike the case where the tensile body layer and the compression rubber layer are integrally molded, even if pressure is applied during bonding, the arrangement of the core wires embedded in the tensile body layer is disturbed in the thickness direction and the width direction. There is no. Further, the tensile body layer 111 can be made common in various transmission belts, and the manufacturing cost of the transmission belt can be greatly reduced. When the rubber member 121A for compression rubber layer used as the compression rubber layer 121 is formed by extrusion molding, cost reduction and improvement in dimensional accuracy can be expected. Moreover, even if the lengths of the transmission belts are different, the rubber member for the compressed rubber layer can be made common. Since the tensile body layer and the rubber member for the compressed rubber layer that becomes the compressed rubber layer can be vulcanized separately, optimum vulcanization can be performed for each.

  In the present embodiment, the V belt has been described as an example. However, by changing the shape of the rubber member 121A for the compressed rubber layer, various transmission belts can be formed using the common tensile layer 111. For example, a V-ribbed belt can be obtained by providing a plurality of grooves in the length direction.

  As a manufacturing method of the V-ribbed belt, for example, there is the following method (for example, refer to Japanese Unexamined Patent Application Publication No. 2009-36302). First, the laminated body which laminated | stacked the rubber sheet and the core wire is formed. Subsequently, as shown in FIG. 12A, the laminate 270 is pressed against the outer mold 260 having the groove 261 to form irregularities, and vulcanized in the pressed state. In this case, since the rubber on the groove 261 side is deformed to form irregularities, the peripheral rubber laminated portion is also deformed. For this reason, at the position between the grooves 261, the rubber is pushed right and left and pushed up to the core wire 271 side. For this reason, the vertical position and the horizontal position of the core wire 271 change at the position between the grooves 261, the distance between the core wires 271 increases at the position of the groove 261, and the vertical position is disturbed. In addition, at the position between the grooves 261, the interval between the core wires 271 is reduced. As described above, in the conventional method for manufacturing a V-ribbed belt, the core wire is formed when the irregularities are formed even if there is no disturbance in the thickness direction and the width direction of the core wire in a state where the rubber sheet and the core wire are laminated. The arrangement in the thickness direction and the width direction is disturbed.

  In the V-ribbed belt in which the arrangement of the core wires in the thickness direction and the width direction is disturbed, the tension between the core wires greatly varies between the pulleys and between the pulleys. For this reason, it becomes easy to cut | disconnect from the part with the highest tension | tensile_strength, and the lifetime of a belt becomes short. On the other hand, according to the method of the present disclosure, the tensile body layer 111 and the rubber member 121A for the compressed rubber layer are bonded after being vulcanized. For this reason, a force that disturbs the arrangement of the core wires 112 in an unvulcanized state is not applied to the tensile body layer 111. For this reason, the arrangement of the core wires 112 hardly occurs, and it is easy to realize a V-ribbed belt in which the core wires 112 are aligned in the thickness direction and the width direction as shown in FIG.

  Moreover, regular unevenness | corrugation can be provided in the rubber member 121A for compression rubber layers, and it can be set as a cogged belt. Furthermore, as shown in FIG. 13, a double cogged belt in which a compression rubber layer is provided on both the inner peripheral surface and the outer peripheral surface of the tensile body layer 111 can be used. In this case, the first compression rubber layer rubber member 125 that adheres to the inner peripheral surface and the second compression rubber layer rubber member 126 that adheres to the outer peripheral surface can have different shapes. Further, the first rubber member for a compressed rubber layer 125 and the second rubber member for a compressed rubber layer 126 can have different blending compositions. The first compression rubber layer rubber member 125 and the second compression rubber layer rubber member 126 may be vulcanized under different conditions. Thereby, for example, a double cog belt can be easily formed.

  The power transmission belt of this embodiment can be a low-edge belt. However, after the tensile body layer 111 and the compression rubber layer 121 are bonded together, the power transmission belt is covered with a skin canvas 127, as shown in FIG. It can also be a belt.

  The toothed belt shown in FIG. 15 can also be formed by the method for manufacturing the transmission belt of the present embodiment. Moreover, this indication is not limited to the above embodiment, It is possible to apply to various transmission belts.

  Hereinafter, the present disclosure will be described in detail with reference to examples, but the present disclosure is not limited to only these examples. A V-ribbed belt is shown as an example.

−Creation of belt−
<Tension layer>
A first unvulcanized rubber sheet to be a cover rubber layer is wound around the outer peripheral surface of a cylindrical molding drum having a smooth surface, and then a second unvulcanized rubber sheet to be an adhesive rubber layer is wound, and then the front The treated core wire was spun into a spiral shape, and a third unvulcanized rubber sheet serving as an adhesive rubber layer was wound around to produce a cylindrical laminate. After the laminated body on the mold was covered with a rubber sleeve, it was heated (about 160 ° C.) and pressurized (about 1.0 MPa) in a vulcanizing can, and the vulcanization time was about 30 minutes. An unvulcanized rubber sheet was integrated to produce an endless tensile body layer.

  The first unvulcanized rubber sheet serving as the cover rubber layer and the second and third unvulcanized rubber sheets serving as the adhesive rubber layer were formulated as shown in Table 1 and Table 2, respectively. A Banbury mixer was used for kneading. The thickness of the first unvulcanized rubber sheet serving as the cover rubber layer was 0.5 mm, and the thickness of the second and third unvulcanized sheets serving as the adhesive rubber layer was 0.4 mm. Each unvulcanized rubber sheet was formed by calendar. In Tables 1 and 2, TMTD is tetramethylthiuram disulfide, and MBT is 2-mercaptobenzothiazole.

  The core wire was polyethylene terephthalate. For the core wire, the process of dipping in the RFL treatment solution and baking was repeated a plurality of times. Thereafter, the core wire was dipped in rubber paste and dried by heating, and then wound up and used. As the rubber paste, a rubber compound having the composition shown in Table 2 was dissolved in toluene.

<Rubber member for compression rubber layer>
After the rubber compound having the composition shown in Table 1 was kneaded using a Banbury mixer, the kneaded rubber compound was pelletized. The pellet-shaped rubber compound was supplied to an extruder with a uniaxial vent having a rib groove-shaped die having the same width as that of the tensile layer, and an unvulcanized rubber member having a rib groove shape was extruded. Next, it vulcanized | cured continuously using the funnel press shown in FIG. Specifically, an unvulcanized rubber member was continuously supplied with a rib portion aligned to a cylindrical metal drum having a groove matched to the rib shape in the circumferential direction of the outer peripheral surface. An unvulcanized rubber member was sandwiched between a metal drum and a steel band and continuously press vulcanized at a predetermined temperature and pressure to obtain a rib-shaped rubber member for a compressed rubber layer. The vulcanization temperature was about 160 ° C., the pressure was about 1.0 MPa, and the time was about 30 minutes.

<Adhesion>
Adhesion between the tensile body layer and the rubber member for the compression rubber layer and adhesion between the end portions of the rubber member for the compression rubber layer were performed using an adhesive rubber sheet. The adhesive rubber sheet had the composition shown in Table 3. The rubber sheet for bonding was kneaded using a Banbury mixer, and then formed into a sheet having a thickness of 0.3 mm using a calendar. In Table 3, TRA is dipentamethylene thiuram tetrasulfide, PZ is zinc dimethyldithiocarbamate, PPD is pentamethylene dithiocarbamate piperidine salt, and TTTE is tellurium diethyldiocarbamate.

  An adhesive rubber sheet was wound around the tensile layer that was vulcanized on the surface of the cylindrical mold. Next, a rubber member for a compressed rubber layer press-vulcanized into a rib shape cut with an ultrasonic cutter in accordance with a predetermined peripheral length was bonded onto the adhesive rubber sheet. Both ends in the length direction of the rubber member for the compressed rubber layer were cut at an angle of 45 ° so as to coincide with each other. An unvulcanized adhesive rubber sheet was stuck to this cut surface, and the end surfaces were butted together. Next, a rubber sleeve was attached to the surface of the molded body, and heated and pressurized to bond the tensile band layer and the rubber member for the compressed rubber layer. Adhesion was performed in a pressure oven at a temperature of 60 ° C. and a pressure of 1.0 MPa for 24 hours. Thereafter, the cylindrical slab in which the tensile body layer and the compression rubber layer were bonded was removed from the cylindrical mold and cut into a predetermined number of ribs (width) to produce a V-ribbed belt.

-Evaluation of adhesion-
<Evaluation method>
The evaluation of adhesiveness was performed in accordance with JIS K6854-3: 1999 "Adhesive-Peeling adhesive strength test method-Part 3: T-peeling". The peeling speed was 100 mm / min, and the adhesiveness was evaluated by the maximum peeling force.

Example 1
A first vulcanized rubber sheet having the composition shown in Table 1 and a second vulcanized rubber sheet having the composition shown in Table 2 were prepared, and an unvulcanized adhesive rubber sheet having the composition shown in Table 3 was interposed between them. A sample for evaluation was vulcanized in a state where it was sandwiched between and pressurized. The thickness of the 1st rubber sheet and the 2nd rubber sheet was 3 mm, respectively. The thickness of the adhesive rubber sheet was 0.3 mm. Each compound was kneaded using a Banbury mixer and processed into a sheet having a predetermined thickness by a calendar. The vulcanization conditions were a pressure of 1.0 MPa, a vulcanization temperature of 170 ° C., and a vulcanization time of 5 minutes.

(Example 2)
Example 1 was repeated except that the vulcanization temperature was 60 ° C. and the vulcanization time was 24 hours.

(Comparative Example 1)
The procedure was the same as Example 1 except that the composition of the adhesive rubber was as shown in Table 2.

(Comparative Example 2)
Example 2 was the same as Example 2 except that the composition of the adhesive rubber was as shown in Table 2.

  Table 4 summarizes the sample preparation conditions and the maximum peeling force for each example and comparative example. The maximum peeling force is shown as a maximum peeling force index normalized as an index with the maximum peeling force of Comparative Example 1 as 100. As shown in Table 4, the maximum peel force index was 153 in Example 1 in which the adhesive rubber having the composition shown in Table 3 was vulcanized at 170 ° C. for 5 minutes. In Example 2 vulcanized at 60 ° C. for 24 hours, the maximum peeling force index was 110. On the other hand, in the case of Comparative Example 2 in which the adhesive rubber had the composition shown in Table 2 and was vulcanized at 60 ° C. for 24 hours, the maximum peel force index was 72.

  The transmission belt and the manufacturing method thereof of the present disclosure are less likely to be disturbed in the pitch of the core wire, and are useful as the transmission belt and the manufacturing method thereof.

111 Tensile layer 112 Core wire 114 Canvas 115 Adhesive rubber layer 116 Cover rubber layer 121 Compressed rubber layer 121A Compressed rubber layer rubber member 121a Adhesive part 122 Adhesive rubber layer 122A Sheet 123 Adhesive rubber 124 Canvas 125 First compression Rubber member for rubber layer 126 Second rubber member for compressed rubber layer 127 Skin canvas 211 Molding drum 213 First unvulcanized rubber sheet 214 Second unvulcanized rubber sheet 215 Third unvulcanized rubber sheet 232 Metal Drum 233 Pulley 240 Steel band 251 Unvulcanized rubber member 260 Outer mold 261 Groove 270 Laminated body 271 Core wire

Claims (8)

Forming and vulcanizing an endless tensile body layer embedded with a core wire extending in the belt length direction; and
Forming and vulcanizing the rubber member for the compressed rubber layer;
A step of bonding the vulcanized tensile layer and the vulcanized rubber member for the compressed rubber layer with an adhesive rubber interposed therebetween,
The method for producing a transmission belt, wherein the adhesive rubber includes at least one of a thiazole vulcanization accelerator and an organic amine vulcanization accelerator.   The method for manufacturing a transmission belt according to claim 1, wherein in the bonding step, both end portions in the length direction of the rubber member for the compressed rubber layer are bonded to each other.   The method for manufacturing a transmission belt according to claim 1, further comprising a step of bonding both end portions in the length direction of the rubber member for the compressed rubber layer to each other before the bonding step.   The method for manufacturing a transmission belt according to any one of claims 1 to 3, wherein the tensile body layer and the rubber member for the compression rubber layer are vulcanized under different conditions.   In the bonding step, the first rubber member for the compression rubber layer is bonded to the inner peripheral side of the tensile body layer, and the second rubber member for the compression rubber layer is bonded to the outer peripheral surface of the tensile body layer. The manufacturing method of the transmission belt of any one of Claims 1-4 which is a process. An endless tensile body layer embedded with a core extending in the belt length direction;
A compressed rubber layer bonded to the tensile body layer;
An adhesive rubber layer provided between the tensile body layer and the compressed rubber layer,
The adhesive rubber layer is a power transmission belt including at least one of a thiazole vulcanization accelerator and an organic amine vulcanization accelerator.   The transmission belt according to claim 6, wherein the compressed rubber layer has an adhesive portion in which end portions in the belt length direction are adhered to each other.   The power transmission belt manufactured by the method of any one of Claims 1-5.

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