JP6007353B2 - V-ribbed belt, method for manufacturing the same, and belt transmission device - Google Patents

Description

  The present invention relates to a V-ribbed belt, a manufacturing method thereof, and a belt transmission device.

  By forming the compression rubber layer of the V-ribbed belt with porous rubber, a technology is provided to provide a large number of concave holes on the surface of the V-rib that is the pulley contact portion, thereby suppressing noise generation during running of the belt, especially when it is wet. Are known.

  For example, Patent Documents 1 to 4 disclose that at least the surface portion of the V-rib of the V-ribbed belt is formed of a porous rubber made of a rubber composition containing hollow particles.

WO2012 / 053176 WO2011 / 074182 WO2009 / 101799 WO2008 / 007647

The V-ribbed belt of the present invention is a V-ribbed belt in which a plurality of V-ribs extending in the belt length direction are arranged in parallel in the belt width direction, and each of the plurality of V-ribs is porous on both sides. A pair of V ribs adjacent to each other in the plurality of V ribs, and a pair of side surfaces facing each other, and a rib bottom portion connecting them are formed of rubber and the tip is formed of solid rubber . The cross-sectional shape is integrally formed of a layer of porous rubber having an inverted U shape .

  The belt transmission device of the present invention is obtained by winding the V-ribbed belt of the present invention around a plurality of pulleys.

  The manufacturing method of the V-ribbed belt of the present invention includes producing a V-rib precursor having an inner portion formed of solid rubber and a covering layer formed of porous rubber, and grinding the V-rib precursor. , V-ribs having both side surface portions made of porous rubber and tip portions made of solid rubber are formed.

  The method of manufacturing the V-ribbed belt of the present invention includes forming a cylindrical belt slab in which a solid rubber layer is laminated on the surface of a porous rubber layer, and grinding the outer periphery of the belt slab in the circumferential direction. A V-rib having a surface portion made of porous rubber and a tip portion made of solid rubber is formed.

3 is a perspective view of a V-ribbed belt according to Embodiment 1. FIG. 3 is a cross-sectional view of one V-rib of the V-ribbed belt according to Embodiment 1. FIG. It is sectional drawing for one V rib of the modification of the V ribbed belt which concerns on Embodiment 1. FIG. It is a figure which shows the pulley layout of the auxiliary machine drive belt transmission of the motor vehicle which concerns on Embodiment 1. FIG. 2 is a longitudinal sectional view of a belt forming die used for manufacturing the V-ribbed belt according to Embodiment 1. FIG. FIG. 3 is an enlarged longitudinal sectional view of a part of a belt forming die used for manufacturing the V-ribbed belt according to the first embodiment. FIG. 5 is a first explanatory view showing a method for manufacturing the V-ribbed belt according to the first embodiment. FIG. 6 is a second explanatory view showing the method for manufacturing the V-ribbed belt according to the first embodiment. FIG. 6 is a third explanatory view showing the method for manufacturing the V-ribbed belt according to the first embodiment. FIG. 6 is a fourth explanatory view showing the method for manufacturing the V-ribbed belt according to the first embodiment. FIG. 9 is a fifth explanatory view showing the method for manufacturing the V-ribbed belt according to the first embodiment. FIG. 10 is a sixth explanatory view showing the method for manufacturing the V-ribbed belt according to the first embodiment. 6 is a perspective view of a V-ribbed belt according to Embodiment 2. FIG. 6 is a cross-sectional view of one V-rib of the V-ribbed belt according to Embodiment 2. FIG. 6 is a first explanatory view showing a method for manufacturing a V-ribbed belt according to Embodiment 2. FIG. FIG. 10 is a second explanatory view showing the method for manufacturing the V-ribbed belt according to the second embodiment. FIG. 10 is a third explanatory view showing the method for manufacturing the V-ribbed belt according to the second embodiment. FIG. 10 is a fourth explanatory view showing the method for manufacturing the V-ribbed belt according to the second embodiment.

  Hereinafter, embodiments will be described in detail with reference to the drawings.

(Embodiment 1)
<V-ribbed belt B>
1 and 2 show a V-ribbed belt B according to the first embodiment. The V-ribbed belt B according to the first embodiment is, for example, an endless belt used in an auxiliary machine drive belt transmission device or the like provided in an engine room of an automobile. For example, the V-ribbed belt B according to the first embodiment has a belt length of 700 to 3000 mm, a belt width of 10 to 36 mm, and a belt thickness of 4.0 to 5.0 mm.

  The V-ribbed belt B according to the first embodiment is a rubber configured as a triple layer of a compression rubber layer 11 that forms a pulley contact portion on the inner peripheral side of the belt, an intermediate adhesive rubber layer 12, and a back rubber layer 13 on the outer peripheral side of the belt. A V-ribbed belt main body 10 is provided. A core wire 14 is embedded in an intermediate portion in the thickness direction of the adhesive rubber layer 12 so as to form a spiral having a pitch in the belt width direction. A back reinforcing cloth may be provided instead of the back rubber layer 13, and the V-ribbed belt main body 10 may be configured as a double layer of the compression rubber layer 11 and the adhesive rubber layer 12.

  The compressed rubber layer 11 is provided such that a plurality of V ribs 15 hang down to the belt inner peripheral side. The plurality of V ribs 15 are each formed in a ridge having a substantially inverted triangular cross section extending in the belt length direction, and provided in parallel in the belt width direction. Each V rib 15 has, for example, a rib height of 2.0 to 3.0 mm and a width between base ends of 1.0 to 3.6 mm. The number of V ribs 15 is, for example, 3 to 6 (6 in FIG. 1).

  Both side surface portions 15a of each V rib 15 in the compressed rubber layer 11 and a rib bottom portion 15c that connects opposing side surface portions 15a of a pair of adjacent V ribs 15 are formed of layered porous rubber. Accordingly, in the pair of V ribs 15 adjacent to each other in the plurality of V ribs 15, the pair of side surface portions 15a facing each other and the rib bottom portion 15c connecting them are made of porous rubber having a reverse U-shaped cross section. It is integrally formed with layers. The thickness of the porous rubber layer is, for example, 50 to 500 μm.

  A large number of hollow portions 16 are formed in the porous rubber layer forming the side surface portion 15a and the rib bottom portion 15c of the V-rib 15, and a large number of concave holes 17 are formed on the surface thereof. . The average pore diameter of the concave holes 17 is preferably 40 μm or more, more preferably 80 μm or more, and preferably 150 μm or less, more preferably 120 μm or less. The average hole diameter of the concave holes 17 is determined by the number average of 50 to 100 measured by the surface image.

  On the other hand, the other V-rib main body 15d in the compressed rubber layer 11 is made of solid rubber. Therefore, in the V-ribbed belt B according to the first embodiment, each of the plurality of V-ribs 15 in the compressed rubber layer 11 has both side surface portions 15a formed of porous rubber and the tip portion 15b formed of solid rubber. As shown in FIG. 2, the tip 15 b of the V rib 15 may be formed of a solid rubber layer having a certain thickness from the tip of the V rib 15. The thickness d of the layer is, for example, 0.10 to 0.40 mm. The width w of the solid rubber at the tip portion 15b of the V rib 15 is, for example, 1.50 to 2.17 mm. As shown in FIG. 3, the distal end portion 15 b of the V rib 15 may be configured by a top surface of the V rib 15 from which a solid rubber having no thickness is exposed. In this case, the width w of the solid rubber at the tip portion 15b of the V rib 15 is, for example, 1.04 to 1.50 mm.

  Here, “porous rubber” in the present application means a crosslinked rubber composition having a large number of hollow portions 16 inside and a large number of concave holes 17 on the surface. Any of the structure in which the hollow portion 16 and the concave hole 17 communicate with each other is included. Further, “solid rubber” in the present application means a crosslinked rubber composition other than “porous rubber”.

  The porous rubber is prepared by heating and pressurizing an uncrosslinked rubber composition in which various rubber compounding agents including hollow particles or a foaming agent for forming the hollow portion 16 and the concave hole 17 are blended in the rubber component and kneaded. It is comprised with the rubber composition bridge | crosslinked with the crosslinking agent.

  Examples of the rubber component of the rubber composition constituting the porous rubber include ethylene-α-ethylene copolymers such as ethylene / propylene copolymer (EPR), ethylene / propylene / diene terpolymer (EPDM), ethylene / octene copolymer, and ethylene / butene copolymer. Examples include olefin elastomers; chloroprene rubber (CR); chlorosulfonated polyethylene rubber (CSM); hydrogenated acrylonitrile rubber (H-NBR). Of these, the rubber component is preferably an ethylene-α-olefin elastomer. The rubber component may be composed of a single species or a blend of a plurality of species.

  The rubber composition constituting the porous rubber may be one obtained by crosslinking an uncrosslinked rubber composition in which unexpanded hollow particles for forming the hollow portion 16 and the concave hole 17 are blended with the rubber component. Examples of the unexpanded hollow particles include particles in which a solvent is enclosed in a shell formed of a thermoplastic polymer (for example, acrylonitrile-based polymer). The hollow particles may be mixed with a single type or with multiple types. The particle size of the unexpanded hollow particles is preferably 15 μm or more, more preferably 25 μm or more, and preferably 50 μm or less, more preferably 35 μm or less. The blending amount of the hollow particles is preferably 0.5 parts by mass or more, more preferably 1.0 parts by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts per 100 parts by mass of the rubber component. 0.0 parts by mass or less. Examples of commercially available hollow particles include EXPANCEL 092-120 (particle size 28-38 μm), 009-80 (particle size 18-24 μm) manufactured by Nippon Philite Co., Ltd., ADVANCEL manufactured by Sekisui Chemical Co., Ltd. (Advancel) EMH204 (particle size 23-29 μm), EMS-026 (particle size 25-35 μm), Matsumoto Microsphere F-80S (particle size 20-30 μm), F-190D (particle size) manufactured by Matsumoto Yushi Seiyaku Co., Ltd. 30 to 40 μm). When hollow particles are used, the rubber composition constituting the porous rubber is provided with a large number of hollow portions 16 having a shell formed by hollow particles expanded inside and dispersed, and a shell of hollow particles on the surface. A large number of concave holes 17 that are broken and opened are exposed.

  The rubber composition constituting the porous rubber may be obtained by crosslinking an uncrosslinked rubber composition in which a foaming agent for forming the hollow portion 16 and the concave hole 17 is blended with the rubber component. As the foaming agent, for example, an ADCA foaming agent containing azodicarbonamide as a main component, a DPT foaming agent containing dinitrosopentamethylenetetramine as a main component, and p, p′-oxybisbenzenesulfonylhydrazide as a main component. Examples thereof include organic foaming agents such as OBSH foaming agents and HDCA foaming agents mainly composed of hydrazodicarbonamide. The foaming agent may be either a single type or a plurality of types. The blending amount of the foaming agent is preferably 0.5 parts by mass or more, more preferably 4 parts by mass or more, and preferably 10 parts by mass or less, more preferably 7 parts by mass with respect to 100 parts by mass of the rubber component. It is as follows. In addition, as a commercially available foaming agent, the Sankyo Kasei Co., Ltd. brand name: Cell microphone series etc. are mentioned, for example. When a foaming agent is used, the rubber composition constituting the porous rubber has a large number of hollow portions 16 that do not have a shell formed by foaming of the foaming agent dispersed therein, and a shell on the surface. A large number of concave holes 17 that are not present are exposed. The rubber composition constituting the porous rubber may be a combination of both hollow particles and a foaming agent.

  Examples of other rubber compounding agents blended in the rubber composition constituting the porous rubber include reinforcing materials such as carbon black, oil, processing aids, vulcanization aids, crosslinking agents, vulcanization accelerators, and the like. It is done. However, it is preferable that the short fiber is not mix | blended with the rubber composition which comprises porous rubber. The rubber composition constituting the porous rubber may be a sulfur cross-linked rubber composition using sulfur as a cross-linking agent, or an organic peroxide cross-linked rubber composition using an organic peroxide as a cross-linking agent. It may be a product, or may be a combined cross-linked rubber composition using them in combination.

  The solid rubber is composed of a rubber composition in which an uncrosslinked rubber composition obtained by mixing and kneading various rubber compounding ingredients with a rubber component is heated and pressurized and crosslinked with a crosslinking agent.

  Examples of the rubber component of the rubber composition constituting the solid rubber include those similar to the rubber composition constituting the porous rubber. The rubber composition constituting the solid rubber preferably has the same rubber component as that of the rubber composition constituting the porous rubber.

  Examples of the rubber compounding agent for the rubber composition constituting the solid rubber include those similar to the rubber composition constituting the porous rubber. However, the rubber composition constituting the solid rubber does not contain a rubber compounding agent for forming the hollow portion 16 and the concave hole 17 such as hollow particles and a foaming agent. Short fibers may be blended in the rubber composition constituting the solid rubber. The rubber composition constituting the solid rubber is the same as the rubber composition constituting the porous rubber except for the rubber compounding agent for forming the hollow portions 16 and the concave holes 17 such as hollow particles and foaming agents. Also good.

  The adhesive rubber layer 12 is configured in a band shape having a horizontally long cross section, and has a thickness of, for example, 1.0 to 2.5 mm. The back rubber layer 13 is also formed in a band shape having a horizontally long cross section, and has a thickness of, for example, 0.4 to 0.8 mm. It is preferable that a woven fabric pattern is provided on the surface of the back rubber layer 13 from the viewpoint of suppressing noise generation during back driving. Each of the adhesive rubber layer 12 and the back rubber layer 13 is formed of a rubber composition in which an uncrosslinked rubber composition in which various rubber compounding agents are blended with a rubber component and kneaded is heated and pressurized to be crosslinked with the crosslinking agent. Has been.

  Examples of the rubber component of the rubber composition forming the adhesive rubber layer 12 and the back rubber layer 13 include the same rubber components as those constituting the porous rubber. The rubber composition for forming the adhesive rubber layer 12 and the back rubber layer 13 preferably has the same rubber component as the rubber composition constituting the porous rubber or the solid rubber.

  Examples of the rubber compounding agent of the rubber composition that forms the adhesive rubber layer 12 and the back rubber layer 13 include the same rubber composition as that of the porous rubber. However, it is preferable that the rubber composition for forming the adhesive rubber layer 12 and the back rubber layer 13 does not contain a rubber compounding agent for forming the hollow part 16 and the concave hole 17 such as hollow particles or a foaming agent. . Short fibers may be blended in the rubber composition forming the adhesive rubber layer 12 and the back rubber layer 13.

  The core wire 14 is composed of a twisted yarn formed of polyamide fiber, polyester fiber, aramid fiber, polyamide fiber or the like. The diameter of the core wire 14 is, for example, 0.5 to 2.5 mm, and the dimension between the centers of the adjacent core wires 14 in the cross section is, for example, 0.05 to 0.20 mm. The core wire 14 is subjected to an adhesion process for adhesion to the adhesive rubber layer 12 of the V-ribbed belt main body 10.

  Normally, if the surface portion of the V-rib of the V-ribbed belt is made of porous rubber, it is possible to obtain an excellent noise generation suppression effect during belt running, but bending is repeated at the tip of the V-rib that does not contact the pulley. As a result, there is a risk that the concave holes on the surface become the starting point of cracks. However, according to the V-ribbed belt B according to the embodiment having the above-described configuration, both side surface portions 15a that contact the pulley of the V-rib 15 are formed of porous rubber. The effect of suppressing noise generation can be obtained. In particular, at the time of flooding, the drainage action of the porous rubber can also help to obtain a remarkably excellent noise generation suppression effect. In addition, since the tip 15b that does not contact the pulley is made of solid rubber, the surface of the tip is recessed by repeated bending as in the case where the tip is made of porous rubber. A hole does not become a starting point of a crack, and excellent bending fatigue resistance can be obtained.

<Automotive accessory drive belt drive>
FIG. 4 shows a pulley layout of an auxiliary drive belt transmission device 20 for an automobile using the V-ribbed belt B according to the embodiment. The accessory drive belt transmission device 20 is of a serpentine drive type in which a V-ribbed belt B is wound around six pulleys of four rib pulleys and two flat pulleys to transmit power.

  In this accessory drive belt transmission device 20, a power steering pulley 21 of a rib pulley is provided at the uppermost position, and an AC generator pulley 22 of a rib pulley is provided diagonally to the right of the power steering pulley 21. Further, a flat pulley tensioner pulley 23 is provided diagonally to the left of the power steering pulley 21, and a flat pulley water pump pulley 24 is provided below the tensioner pulley 23. Further, a rib pulley crankshaft pulley 25 is provided diagonally to the left of the tensioner pulley 23 and the water pump pulley 24, and a rib pulley air conditioner pulley 26 is provided diagonally to the right of the water pump pulley 24 and the crankshaft pulley 25. It has been. These pulleys are made of, for example, a metal press-worked product, a cast, a resin molded product such as a nylon resin, a phenol resin, and the diameter of the pulley is 50 to 150 mm.

  In this accessory drive belt transmission device 20, the V-ribbed belt B is wound around the power steering pulley 21 so that the V-rib 15 side comes into contact, and then around the tensioner pulley 23 so that the back surface of the belt comes into contact. After that, it is wound around the crankshaft pulley 25 and the air conditioner pulley 26 in order so that the V-rib 15 side comes into contact, and is further wound around the water pump pulley 24 so that the back surface of the belt comes into contact. Thus, it is wound around the AC generator pulley 22 and finally returned to the power steering pulley 21. The belt span length, which is the length of the V-ribbed belt B spanned between the pulleys, is, for example, 50 to 300 mm. Misalignment that can occur between pulleys is 0-2 °.

<Method for producing V-ribbed belt B>
A method for manufacturing the V-ribbed belt B according to the first embodiment will be described with reference to FIGS.

  5 and 6 show a belt mold 30 used for manufacturing the V-ribbed belt B according to the first embodiment.

  The belt forming die 30 includes a cylindrical inner die 31 and an outer die 32 that are provided concentrically.

  The inner mold 31 is made of a flexible material such as rubber. The outer mold 32 is made of a rigid material such as metal. The inner peripheral surface of the outer mold 32 is formed as a molding surface, and V-rib precursor forming grooves 33 that are slightly larger than the V-rib 15 are provided on the inner peripheral surface of the outer mold 32 at a constant pitch in the axial direction. It has been. The outer mold 32 is provided with a temperature control mechanism that controls the temperature by circulating a heat medium such as water vapor or a coolant such as water. Further, a pressurizing means for pressurizing and expanding the inner mold 31 from the inside is provided.

  The manufacturing method of the V-ribbed belt B according to Embodiment 1 includes a preparation process, a molding process, a crosslinking process, a grinding process, and a width cutting process.

―Preparation process―
In the manufacture of the V-ribbed belt B according to the first embodiment, first, each rubber compounding agent is blended with the rubber component and kneaded by a kneader such as a kneader or a Banbury mixer, and the obtained uncrosslinked rubber composition is formed by calendar molding or the like. Formed into a sheet shape, uncrosslinked rubber sheets 15a ′ and 15d ′ for the side portions of the V-rib 15 and the V-rib main body of the compressed rubber layer 11 are respectively produced. At this time, in the uncrosslinked rubber sheet 15a ′ for the side surface portion of the V-rib 15, a rubber compounding agent for forming the hollow portion 16 and the concave hole 17 such as a hollow particle or a foaming agent is blended. Similarly, uncrosslinked rubber sheets 12 ′ and 13 ′ for the adhesive rubber layer and the back rubber layer are also produced.

  Further, an adhesion treatment is performed on the twisted yarn 14 ′ constituting the core wire 14. Specifically, the twisted yarn 14 ′ is subjected to an adhesive treatment in which it is immersed in a primer solution and heated, an adhesive treatment in which it is immersed in an RFL aqueous solution and heated, and an adhesive treatment in which it is immersed in rubber paste and dried.

―Molding process―
Next, as shown in FIG. 7, a rubber sleeve 35 is placed on a cylindrical drum 34 having a smooth surface, and an uncrosslinked rubber sheet 13 ′ for the back rubber layer and an uncrosslinked rubber for the adhesive rubber layer are formed on the outer periphery thereof. The sheet 12 'is wound in order and laminated, and then the strand 14' for the core wire is spirally wound around the cylindrical inner mold 31, and the uncrosslinked rubber sheet 12 'for the adhesive rubber layer is further formed thereon. The uncrosslinked rubber sheet 15d ′ for the V-rib body and the uncrosslinked rubber sheet 15a ′ for the side surface portion of the V-rib 15 are wound in order. At this time, a laminated molded body B ′ is formed on the rubber sleeve 35.

―Crosslinking process―
Next, the rubber sleeve 35 provided with the laminated molded body B ′ is removed from the cylindrical drum 34 and, as shown in FIG. 8, it is set in the inner peripheral surface side of the outer mold 32 and then shown in FIG. 9. As described above, the inner mold 31 is positioned and sealed in the rubber sleeve 35 set in the outer mold 32.

  Subsequently, the outer mold 32 is heated, and high-pressure air or the like is injected into the sealed interior of the inner mold 31 to pressurize it. At this time, the inner mold 31 expands, and the uncrosslinked rubber sheets 15a ′, 15d ′, 12 ′, and 13 ′ for forming the belt of the laminated molded body B ′ are compressed on the molding surface of the outer mold 32. The cross-linking proceeds and integrates and is combined with the twisted yarn 14 ′, and further, a large number of hollow portions 16 are formed in the portion corresponding to the uncrosslinked rubber sheet 15a ′, and finally, as shown in FIG. A cylindrical belt slab S is molded. Further, on the outer periphery of the molded belt slab S, an inner portion 15d ″ is formed of a solid rubber corresponding to the V-rib precursor forming groove 33, and a covering layer 15a ″ covering the whole is formed of a porous rubber. A V-rib precursor 15 ′ having a substantially trapezoidal cross-sectional shape extending in the circumferential direction is formed to be continuous in the axial direction. The molding temperature of the belt slab S is, for example, 100 to 180 ° C., the molding pressure is, for example, 0.5 to 2.0 MPa, and the molding time is, for example, 10 to 60 minutes.

―Grinding process―
Then, the inside of the inner mold 31 is depressurized to release the sealing, and the belt slab S molded between the inner mold 31 and the outer mold 32 via the rubber sleeve 35 is taken out. As shown in FIG. S is spanned between a pair of slab spanning shafts 36, and the belt slab S is in contact with the outer periphery of the belt slab S while rotating a grinding wheel 37 in which a circumferentially extending V-rib-shaped groove is continuously provided in the axial direction of the outer periphery. The belt slab S is also rotated between the pair of slab spanning shafts 36. At this time, as shown in FIG. 12, the V-rib precursor 15 ′ on the outer periphery of the belt slab S was ground, so that both side surface portions 15a were formed of porous rubber and the tip portion 15b was formed of solid rubber. V-ribs 15 are formed. If necessary, the belt slab S may be divided in the length direction for grinding.

―Width cutting process―
Finally, the belt slab S is cut into a predetermined width and turned upside down to obtain the V-ribbed belt B.

(Embodiment 2)
<V-ribbed belt B>
13 and 14 show a V-ribbed belt B according to the second embodiment. In addition, the part of the same name as Embodiment 1 is shown with the same code | symbol as Embodiment 1. FIG.

  The V-ribbed belt B according to the second embodiment includes a rubber V-ribbed belt main body 10 configured as a double layer of a compression rubber layer 11 on the belt inner peripheral side and an adhesive rubber layer 12 on the belt outer peripheral side. A back reinforcing cloth 18 is attached to the belt outer peripheral side of the adhesive rubber layer 12 in the V-ribbed belt main body 10. A core wire 14 is embedded in an intermediate portion in the thickness direction of the adhesive rubber layer 12 so as to form a spiral having a pitch in the belt width direction. Note that a back rubber layer may be provided instead of the back reinforcing cloth 18, and the V-ribbed belt main body 10 may be configured as a triple layer of a compression rubber layer 11, an adhesive rubber layer 12, and a back rubber layer.

  The compressed rubber layer 11 has a two-layer structure in which a layer having a certain thickness from the tip of the V-rib 15 is formed of solid rubber, and the other V-rib body 15d is formed of porous rubber. Therefore, in the V-ribbed belt B according to the second embodiment, each of the plurality of V-ribs 15 in the compressed rubber layer 11 has both side surface portions 15a formed of porous rubber and the tip portion 15b formed of solid rubber. The thickness d of the solid rubber layer of the tip 15b is 0.10 to 0.40 mm. The width w of the solid rubber at the tip portion 15b of the V rib 15 is, for example, 1.50 to 2.17 mm. The configurations of the porous rubber and the solid rubber are the same as those in the first embodiment.

  The back reinforcing cloth 18 is made of, for example, a cloth material such as a woven fabric, a knitted fabric, or a non-woven fabric formed of yarns such as cotton, polyamide fiber, polyester fiber, and aramid fiber. The thickness of the back reinforcing cloth 18 is, for example, 0.4 to 1.5 mm. The back reinforcing cloth 18 is subjected to an adhesion treatment for adhesion to the adhesive rubber layer 12 of the V-ribbed belt main body 10.

  Other configurations, operations, and effects are the same as those of the first embodiment.

<Method for producing V-ribbed belt B>
A method for manufacturing the V-ribbed belt B according to the second embodiment will be described with reference to FIGS.

  The manufacturing method of the V-ribbed belt B according to Embodiment 2 includes a preparation process, a molding process, a crosslinking process, a grinding process, and a width cutting process.

―Preparation process―
In the manufacture of the V-ribbed belt B according to the second embodiment, first, each rubber compounding agent is blended with the rubber component and kneaded by a kneader such as a kneader or a Banbury mixer. The non-crosslinked rubber sheets 15 d ′ and 15 b ′ for the V-rib body of the compressed rubber layer 11 and the tip of the V-rib 15 are formed into a sheet shape. At this time, a rubber compounding agent for forming the hollow portion 16 and the concave hole 17 such as hollow particles or a foaming agent is blended in the uncrosslinked rubber sheet 15d ′ for the V-rib body. Similarly, an uncrosslinked rubber sheet 12 ′ for the adhesive rubber layer is also produced.

  Further, an adhesive treatment is applied to the cloth material 18 ′ constituting the back reinforcing cloth 18. Specifically, for the cloth material 18 ′, an adhesion treatment in which it is immersed in a primer solution and heated, an adhesion treatment in which it is immersed in an RFL aqueous solution and heated, an adhesion treatment in which it is immersed in rubber glue and dried, and a V-ribbed belt body One or two or more types of adhesive treatments are applied among the adhesive treatments in which the surface on the 10 side is coated with rubber paste and dried.

  Further, an adhesive treatment is applied to the twisted yarn 14 ′ constituting the core wire 14. Specifically, the twisted yarn 14 ′ is subjected to an adhesive treatment in which it is immersed in a primer solution and heated, an adhesive treatment in which it is immersed in an RFL aqueous solution and heated, and an adhesive treatment in which it is immersed in rubber paste and dried.

―Molding process―
Next, as shown in FIG. 15, on the outer periphery of the cylindrical mold 38, the cloth material 18 ′ subjected to the adhesion treatment and the uncrosslinked rubber sheet 12 ′ for the adhesion rubber layer are wound in order and laminated, and then adhered thereon. The treated twisted yarn 14 ′ is wound around the cylindrical mold 38 with a certain tension applied in a spiral manner, and the uncrosslinked rubber sheet 12 ′ for the adhesive rubber layer and the uncrosslinked rubber for the V-rib main body are further wound thereon. The sheet 15d ′ and the uncrosslinked rubber sheet 15b ′ for the tip of the V-rib 15 are wound in order. At this time, the laminated molded body B ′ is formed on the cylindrical mold 38.

-Crosslinking step-
Subsequently, as shown in FIG. 16, the laminated molded body B ′ is covered with a rubber sleeve 35, placed in a vulcanizing can and sealed, and the vulcanizing can is filled with high-temperature and high-pressure steam. Hold for a predetermined time. At this time, the crosslinking of the uncrosslinked rubber sheets 15d ′, 15b ′, 12 ′ proceeds and integrates, and is combined with the cloth material 18 ′ and the twisted yarn 14 ′, and in a portion corresponding to the uncrosslinked rubber sheet 15d ′. A large number of hollow portions 16 are formed. Finally, as shown in FIG. 17, a cylindrical belt slab S in which a solid rubber layer is laminated on the surface of a porous rubber layer is molded.

-Grinding process-
Then, the steam is discharged from the inside of the vulcanizing can to release the seal, the belt slab S molded on the cylindrical mold 38 is die-cut, and the belt slab S is paired as shown in FIG. And a grinding wheel 37 in which V-rib-shaped grooves extending in the circumferential direction are continuously provided in the axial direction of the outer periphery of the belt slab S. The belt slab S is also rotated between the pair of slab spanning shafts 36. At this time, the outer periphery of the slab S is ground over the entire circumference in the circumferential direction. As shown in FIG. 18, both side surface portions 15a are formed of porous rubber on the outer periphery of the belt slab S, and the tip portion 15b is solid rubber. The formed V rib 15 is formed. If necessary, the belt slab S may be divided in the length direction for grinding.

-Width cutting process-
Finally, the belt slab S is cut into a predetermined width and turned upside down to obtain the V-ribbed belt B.

(Other embodiments)
In the first and second embodiments described above, the auxiliary drive belt transmission device 20 for an automobile is shown as the belt transmission device, but the belt transmission device is not particularly limited to this, and may be a belt transmission device for general industries.

  In the first and second embodiments, the V-ribbed belt B having the V-ribs 15 only on the belt inner peripheral side is used. However, the present invention is not limited to this, and V-ribs are provided on both the belt inner peripheral side and the belt outer peripheral side. It may be a double V-ribbed belt.

  INDUSTRIAL APPLICABILITY The present invention is useful in the technical field of a V-ribbed belt, a manufacturing method thereof, and a belt transmission device.

B V-ribbed belt 15 V-rib 15 'V-rib precursor 15a "coating layer 15d" Internal 15a Side surface 15b Tip

Claims (11)

A plurality of V ribs each extending in the belt length direction are V-ribbed belts provided in parallel in the belt width direction,
Each of the plurality of V-ribs is formed of a porous rubber on both side surfaces and a solid rubber on the tip .
In a pair of V ribs adjacent to each other in the plurality of V ribs, a pair of side surface portions facing each other and a rib bottom portion connecting them are integrally formed with a porous rubber layer having an inverted U-shaped cross section. V-ribbed belt that is. The V-ribbed belt according to claim 1,
The rubber composition constituting the porous rubber is a V-ribbed belt obtained by crosslinking an uncrosslinked rubber composition in which at least one of unexpanded hollow particles and a foaming agent is blended with a rubber component. In the V-ribbed belt according to claim 1 or 2,
The V-ribbed belt is configured such that the tip of the V-rib is formed of a solid rubber layer having a certain thickness from the tip of the V-rib. In the V-ribbed belt according to claim 3,
A V-ribbed belt having a solid rubber layer thickness of 0.10 to 0.40 mm. In the V-ribbed belt according to claim 3 or 4,
A V-ribbed belt in which the solid rubber has a width of 1.50 to 2.17 mm at the tip of the V-rib. In the V-ribbed belt according to claim 1 or 2,
The V-ribbed belt is configured such that a tip end portion of the V-rib is formed by a top surface of the V-rib from which a solid rubber having no thickness is exposed. The V-ribbed belt according to claim 6,
A V-ribbed belt in which the solid rubber has a width of 1.04 to 1.50 mm at the tip of the V-rib. In the V-ribbed belt according to any one of claims 1 to 7 ,
A V-ribbed belt in which the porous rubber layer has a thickness of 50 to 500 μm. Belt transmission device V-ribbed belt which has been described is wound in a plurality of pulleys to any one of claims 1 to 8. A method for manufacturing a V-ribbed belt, in which a plurality of V-ribs extending in the belt length direction are provided in parallel in the belt width direction,
By producing a V-rib precursor in which the inside is made of solid rubber and the coating layer covering it is made of porous rubber, and grinding the V-rib precursor, both side portions are made of porous rubber and A method for manufacturing a V-ribbed belt in which a V-rib having a tip formed of solid rubber is formed. A method for manufacturing a V-ribbed belt, in which a plurality of V-ribs extending in the belt length direction are provided in parallel in the belt width direction,
By forming a cylindrical belt slab in which a solid rubber layer is laminated on the surface of the porous rubber layer and grinding the outer periphery of the belt slab in the circumferential direction, both side portions are formed of porous rubber and the tip portion Manufacturing method of a V-ribbed belt in which a V-rib is formed of solid rubber.

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