JP2009030803A - High load transmission belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a belt having an improved life by releasing heat generated in a mounting portion between a block and a center belt, to the outside for cool-down to prevent a failure of the block. <P>SOLUTION: The high load transmission belt comprises: the center belt having core wires embedded in the elastomer; and the block 2 having upper and lower beams connected to each other via a pillar at the center and fitting grooves which are encircled by the upper and lower beams 11, 12 and the pillar 13 and into which the center belt is inserted. Vent grooves 14 are arranged in at least single faces out of the front and rear faces of the upper and lower beams 11, 12 for communicating the fitting grooves 8, 9 with the upper and lower faces of the block to carry air into/out of the fitting grooves 8, 9. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a high load transmission belt in which a block is fitted and fixed at a predetermined pitch along the longitudinal direction of the center belt, and more specifically, heat generated during belt running, in particular, a portion where the center belt and the block are fitted. The present invention relates to an invention that can effectively dissipate the heat generated in the belt to lower the temperature of the belt, thereby suppressing the deterioration of the center belt and the block and extending the life of the high load transmission belt.

  The belt used in the belt type continuously variable transmission is used by being wound around a transmission pulley that changes the effective diameter of the pulley by changing the V groove width of the pulley and adjusts the transmission ratio. Since the side pressure increases, the belt itself must withstand the large side pressure. In addition to continuously variable speed applications, it is necessary to use a belt that can withstand a high load, especially for high load transmission where the durability of a normal rubber belt is insufficient.

  Among such belts, there is a tensile transmission type high-load transmission belt in which a block is fixed to the center belt to increase the strength in the belt width direction. A block made of an elastomer that is relatively harder than the elastomer used for the center belt is fixed to the center belt embedded in the elastomer using a fixing tool such as a bolt or a rivet.

  The required quality of such a high load transmission belt block is, as described above, for the purpose of high load transmission in friction transmission, so bending fatigue, wear resistance, heat resistance, rigidity, impact resistance, etc. It is necessary to have a balanced nature.

  An example of a high load transmission belt that satisfies these requirements is disclosed in Patent Document 1. In this belt, a block having a double structure in which an insert made of metal or the like is coated with a resin composition in which a rubber component is added to a phenolic resin component is used at a portion where the block and the pulley come into contact.

  In the belt as described above, the block can sufficiently withstand the side pressure from the pulley and can transmit high torque power, but the block repeatedly enters and exits the pulley during traveling. Generates great heat. The members that make up the belt gradually deteriorate over time due to the heat, eventually causing problems such as block breakage and deformation, leading to belt failure. .

  Patent Document 1, Patent Document 2, and Patent Document 3 disclose belts that can radiate generated heat to the outside by providing fins or the like in the block or using a heat conductive material as a block material. ing.

JP 61-103032 A Japanese Utility Model Publication No. 63-57845 Japanese Utility Model Publication No. 5-38267

  By providing fins or using a block made of a heat conductive material as described above, the heat accumulated in the block can be radiated to the outside, and the belt temperature can be lowered.

  However, the heat source of the belt is not only between the pulley and the block, but also the block and the center belt always rub against each other during traveling, and heat is generated by friction from that portion. In addition, the movement of the part attached to the block with the center belt is restricted, and the belt is bent by the movement of the part located between the blocks, so the part that repeatedly deforms is limited between the blocks, There is also heat generation from that part.

  The heat stays without being released from the space surrounded by the block and the center belt. The heat particularly deteriorates the center belt, causing cracks in the elastomer portion and fraying of the inner core wire, causing a belt failure due to the cutting of the center belt.

  Therefore, in the present invention, in the high load transmission belt in which the block is mounted on the center belt, the heat generated in the mounting portion between the block and the center belt is discharged to the outside and cooled, thereby extending the life by preventing the failure of the block. The purpose is to provide a belt.

  In order to achieve the above object, in claim 1 of the present invention, a center belt in which a core wire is embedded in an elastomer, an upper beam and a lower beam are connected by a pillar at a central portion, In a high-load transmission belt consisting of a block formed by inserting the center belt into a fitting groove surrounded by pillars, the fitting groove and the upper and lower surfaces of the block are connected to each other on at least one side of the front and rear surfaces of the upper and lower beams. A ventilation groove for allowing air to flow in and out is disposed in the groove.

  According to a second aspect of the present invention, there is provided the high load transmission belt according to the first aspect, wherein a concave portion provided in the upper beam and a ventilation groove in which the concave portion communicates with the inside of the fitting groove are arranged.

  According to a third aspect of the present invention, there is provided a convex portion that fits into the concave portion provided in the upper beam, and the convex portion enters and exits the concave portion while the belt is running so that air in the concave portion is sent into the ventilation groove. The high load transmission belt described in 2 is used.

  In Claim 4, it is set as the high load power transmission belt in any one of Claims 1-3 which are the range whose depth of a ventilation groove is 0.3-1.0 mm, and width is 0.3-1.0 mm.

  Since at least one of the upper and lower beams of the block and at least one of the front and rear surfaces is formed with a ventilation groove that connects the center belt fitting groove and the upper and lower surfaces of the block, the block is surrounded by the center belt. Since the air staying in the space can flow in and out through the ventilation groove, heat generated by friction between the block and the center belt and heat generated by repeated bending of the center belt can be discharged. The space surrounded by the center belt is cooled, the influence of heat on the center belt and the block is reduced, and a belt having a long life can be obtained.

  According to a second aspect of the present invention, the upper beam is provided with a recess and has a ventilation groove communicating with the recess and the fitting groove, and the outside air is caused to flow into the fitting groove by pumping by the movement of the block while the belt is running. Thus, the inside of the fitting groove is cooled.

  In claim 3, in addition to the concave portion of claim 2, by providing a convex portion that fits the concave portion on the surface opposite to the upper beam, when the belt runs and becomes bent on the pulley, the convex portion When the belt comes out of the recess and comes out of the pulley and becomes a straight line, the projection enters the recess and repeats as the belt runs. When the convex portion enters the concave portion, the air in the concave portion is compressed and sent to the ventilation groove communicated with the concave portion, so that the air can be effectively introduced into the fitting groove.

  According to the fourth aspect, by limiting the depth and width dimensions of the ventilation groove to a predetermined range, heat can be discharged more efficiently and air can be introduced from the outside.

  FIG. 1 is a schematic perspective view showing an example of a high load transmission belt 1 according to the present invention, FIG. 2 is a side sectional view thereof, and FIG. 3 is a front view of a block. The high load transmission belt 1 of the present invention is attached to two center belts 3 of the same width formed by embedding a rope-like core body 5 in an elastomer 4 in a spiral shape, and attached to the center belt 3 at a predetermined pitch. It is composed of a plurality of blocks 2. The side faces 6 and 7 of the block have fitting grooves 8 and 9, and the center belt 3 is mounted in the fitting grooves. Both side surfaces 6 and 7 of the block 2 are inclined surfaces that come into contact with the V groove of the pulley, receive the power of the driven pulley, pull the center belt 3 that is locked and fixed, and drive pulley Is transmitted to the driven pulley. A cover canvas 10, which is a feature of the present invention, is laminated and disposed integrally with the center belt 3 on the surface of the center belt 3.

  The block 2 is made of a resin material. As shown in FIG. 1, the block 2 includes an upper beam portion 11 and a lower beam portion 12, and center pillars 13 connecting the central portions of the upper and lower beam portions. As described above, the engagement grooves 8 and 9 of the center belt 3 are formed on the surface, and the groove 15 provided on the upper surface of the center belt 3 on the upper and lower surfaces of the engagement grooves 8 and 9. Convex ridges 7 and 18 that engage with the concave ridges 16 provided on the lower surface are provided.

  The center belt 3 used as the elastomer 4 is a single material such as chloroprene rubber, natural rubber, nitrile rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, chlorosulfonated polyethylene, alkylated chlorosulfonated polyethylene, or the like. And rubber or polyurethane rubber blended appropriately. And as the core 5, a rope selected from polyester fiber, polyamide fiber, aramid fiber, glass fiber, steel wire and the like is used. The core body 5 may be made of a woven fabric, a knitted fabric, a metal thin plate, or the like of the above-mentioned fiber other than a rope embedded in a spiral shape.

  In the present embodiment, the case where the two center belts 3 and 3 are used and mounted in the fitting groove 20 of the block 2 is described. However, another center belt is used. It doesn't matter.

  In the present invention, a ventilation groove 14 is provided on at least one of the front and rear surfaces of the upper beam 11 and the lower beam 12 of the block 2 so that the fitting grooves 8 and 9 of the center belt 3 communicate with the outer peripheral surface of the belt. By providing this ventilation groove 14, the air in the fitting grooves 8, 9 can be exchanged with the outside of the belt. When the belt moves in and out of the linear portion between the pulleys and the inside of the pulley while the belt is running, the upper beams of adjacent blocks repeat separation and approach, and the fitting groove 8 passes through the ventilation groove 14 at that time. Since the air inside 9 is exchanged with the outside of the belt, the inside of the fitting grooves 8 and 9 can be cooled, the deterioration of the center belt 3 and the block 2 due to heat can be reduced, and the long life of the belt It can contribute to the conversion.

  The ventilation groove 17 is not limited to one, and a plurality of ventilation grooves 17 can be provided on the same surface, and various patterns can be adopted in terms of shape. In the form of FIG. 3, the upper beam has a portion with a small thickness and serves as a radiating fin F to lower the temperature of the block. However, the ventilation groove 14 is formed from where the radiating fin is formed. It is formed as a groove communicating with the fitting grooves 8 and 9, and the air in the fitting grooves 8 and 9 is sent out to the outside by the centrifugal force generated during the belt running.

  The embodiment shown in FIG. 4 is the embodiment according to claim 2 and has a recess C in the center of the upper beam 11 and is fitted separately from the ventilation groove 14a leading from the recess C to the fitting grooves 8 and 9. A ventilation groove 14b is provided from the inside of the grooves 8 and 9 to the outside of the belt. The adjacent upper beams 11 are separated from each other in the state of being wound around the pulley, and the separated upper beams 11 approach each other when they are escaped from the pulley and become linear. At that time, the air in the concave portion is compressed and sent to the fitting grooves 8 and 9 through the ventilation groove 14a in the manner of pumping, and on the other hand, through the ventilation groove 14b by the centrifugal force during belt running. Since the air in the fitting grooves 8 and 9 is discharged to the outside, the air in the fitting grooves 8 and 9 can be replaced more efficiently and the cooling efficiency can be increased.

  FIG. 5 shows a further improvement of the example of FIG. 4. In a block in which a concave portion C is provided in the center of the upper beam 11, a convex portion D that fits into the concave portion C on the surface opposite to the upper beam. Is provided. The bent state in which the belt travels and winds around the pulley, and the straight state between the pulleys after escaping from the pulley are repeated, but the convex portion D and the concave portion C of the adjacent block are in the bent state. In a straight line state, the convex portion D is fitted in the concave portion C. When shifting from the bent state to the straight state, the convex portion D enters the concave portion C and compresses the air in the concave portion C. Thereafter, as in the example shown in FIG. 4, the compressed air is sent into the ventilation groove 14 a communicating with the recess C, and then the air flows into the fitting grooves 8 and 9. It can be said that air can be sent by pumping more efficiently and effectively than in the example shown in FIG.

  The width of the ventilation groove 14 is preferably in the range of about 0.3 to 1.0 mm and the depth is in the range of 0.3 to 1.0 mm. If the width is less than 0.3 mm and the depth is less than 0.3 mm, the amount of air flow will be reduced and the effect of cooling the inside of the fitting groove will be less, and if the width exceeds 1.0 mm and the depth exceeds 1.0 mm, the cooling performance However, it is not preferable because it reduces the strength of the block and shortens the life of the belt.

  Further, the ventilation groove may be provided not only on the upper beam 11 but also on the lower beam 12. As shown in FIG. 6, the ventilation grooves 14a and 14b are provided on the upper beam 11, and the ventilation groove 14c is also provided on the lower beam 12. The inside of the fitting grooves 8 and 9 can be further cooled, and the center belt 3 and the block 2 can be cooled to suppress deterioration due to heat.

  The block 2 used in the present invention is basically a block made of a resin composition. The block 2 is made of only the resin composition, and the insert material is made of a metal or the like in the resin composition and has the same substantially letter shape as the block. The surface may be coated with a resin material.

  The insert material is an insert material that provides the side pressure resistance and bending rigidity of the block 2, and examples of the material include aluminum alloys, ceramics, composite materials of ceramics and aluminum, carbon fiber reinforced resin, and iron. It is done.

In terms of imparting lateral pressure resistance and bending rigidity, a metal material is preferable. Among the metal materials, the elastic modulus of aluminum alloy is 7000 kgf / mm ² and the specific gravity is 2.8, whereas iron has an elastic modulus of 22000 kgf. / Mm ² and a specific gravity of 7.8, it can be said that iron is higher in strength. However, for belts that rotate at high speed and generate centrifugal force, the weight of the belt has a significant impact on the service life, thus reducing the weight. It is preferable to use an aluminum alloy that is advantageous in this respect.

  Of course, as described above, as the block 2, a block made of only a resin material having no insert material can be used. When using the block 2 in which the insert material is not embedded, the centrifugal force generated in the belt is small even if it is used at a high speed because the weight can be reduced as compared with the belt using the block in which the insert material is embedded. For example, it is suitable for relatively light loads and high rotation applications such as motorcycles.

  The resin material has a relatively large friction coefficient and excellent wear resistance, and has a higher rigidity than the elastomer 4 constituting the center belt 3, specifically, a hard rubber having a hardness of 90 ° JIS A or more, a hard polyurethane resin, Liquid crystal resin, phenol resin, epoxy resin, polyester resin, acrylic resin, methacrylic resin, polyamide resin, polyamideimide (PAI) resin, polyimide (PI) resin, polyethersulfone (PES) resin, polyetheretherketone (PEEK) Rubber such as resin or synthetic resin is used.

  Among these, a thermoplastic resin such as a polyamide resin is used to manufacture the block by an injection molding method in order to efficiently manufacture the block. Judging from the criteria that a resin with a low coefficient of friction, excellent friction resistance, rigidity and elasticity against bending, and a resin that does not easily break is good, among polyamide resins, It can be said that 4,6-nylon is preferable.

  These resins are reinforced by mixing cotton fibers, chemical fibers such as polyamide fibers and aramid fibers, fibers made of glass fibers, metal fibers, carbon fibers, etc., fillers, whiskers, silica, calcium carbonate and other inorganic materials. Made of resin.

  In this invention, it is possible to mix | blend a fibrous reinforcement and a whisker-like reinforcement in the resin material which forms a block, and a fibrous reinforcement is mix | blended in 15-40 mass%. If it is less than 15% by mass, there is a problem that the reinforcing effect is small and the wear resistance of the block is not sufficient, and if it is less than 40% by mass, it becomes difficult to blend into a resin or injection molding becomes difficult. This is not preferable.

  Examples of the fibrous reinforcing material to be blended with the synthetic resin include aramid fibers, carbon fibers, glass fibers, polyamide fibers, and polyester fibers. Among these, by using a combination of 4,6-nylon and carbon fibers, which are preferable examples of the resin constituting the block, the carbon fibers make use of the wear resistance, impact resistance, and fatigue resistance of 4,6-nylon. It is something that can be done. In addition to the above organic fibers, inorganic fibers such as zinc oxide whisker, potassium titanate whisker, aluminum borate whisker, and calcium carbonate whisker may be blended as the fibrous reinforcing material.

  In addition, the lubricity of the block 2 can be improved by blending molybdenum disulfide, graphite, fluorine resin, or the like. Examples of the fluorine-based resin include polytetrafluoroethylene (PTFE), polyfluorinated ethylene propylene ether (PFPE), tetrafluoroethylene hexafluoropropylene copolymer (PFEP), polyfluorinated alkoxyethylene (PFA), and the like. .

  Also, the center belt 3 is provided with cover canvases 10 on both the upper and lower surfaces, so that the center belt is protected from friction between the center belt and the block that occurs during belt running. By adopting such a configuration, wear of the center belt 3 due to friction with the block 2 is prevented. In particular, when a whisker-like reinforcing material such as zinc oxide whisker is blended in the block 2, the wear on the center belt side tends to become very large due to the whisker while rubbing against the center belt. Can be prevented. Further, by using an aramid fiber as the material for the cover canvas 10, the effect of preventing wear can be further enhanced, and failure due to cutting of the belt can be reduced.

  Examples of the cover canvas 10 that can be used include plain woven fabrics, twill woven fabrics, and satin woven fabrics. All of them need not be aramid fibers. As the aramid fiber, either a para-aramid fiber or a meta-aramid fiber may be used, but it is preferable to use a multifilament yarn obtained by concentrating 0.3 to 1.2 denier raw yarn. In addition to the aramid fiber, a yarn in which a polyamide fiber or a urethane elastic yarn is mixed and twisted can be used, but the ratio of the aramid fiber is preferably 20 to 80% of the total weight of the weft yarn. If the thickness of the raw yarn is less than 0.3 denier, the tensile strength of the cover canvas 10 in the longitudinal direction of the belt is lowered and the wear resistance is inferior. Conversely, if the thickness exceeds 1.2 denier, the rigidity of the cover canvas 10 becomes too high after weaving, which may cause the balance between the warp and weft to become unbalanced or cause wrinkles in the canvas. It is not preferable.

  Examples of the para-aramid fiber include Kevlar, Technora and Twaron as trade names, and examples of the meta-aramid fiber include Nomex and Conex as trade names.

  Further, the warp yarn in the belt width direction may be a filament yarn made of aramid fiber such as para-aramid fiber or meta-aramid fiber as in the case of weft, and other 6-nylon, 6,6-nylon, 12-nylon. Filament yarns such as polyamide fibers, polyvinyl alcohol fibers, and polyester fibers can be used.

Adhesion treatment is performed in order to laminate and bond the cover canvas 10 having such a configuration to the surface of the center belt. Examples of the adhesion treatment include treatment with an RFL solution, an isocyanate solution, or an epoxy solution. The RFL liquid is a mixture of resorcin and formalin condensate in latex. The latex used here is styrene / butadiene / pyridine terpolymer, hydrogenated nitrile rubber, chlorosulfonated polyethylene, epichlorohydrin, etc. The latex. Further, a glueing process, a soaking process, and a coating process in which a rubber paste obtained by melting rubber in a solvent is attached to the surface of the cover canvas 10 can also be cited as an adhesion process.

  In these adhesion treatments, the friction coefficient can be lowered between the block and the cover belt of the center belt by blending a friction coefficient reducing material with an adhesion treatment agent such as an RFL solution, an isocyanate solution, an epoxy solution, or rubber glue. Further, it is possible to prevent wear due to friction between the block containing the whisker such as zinc oxide and the center belt. Specific examples of the friction coefficient reducing material include polytetrafluoroethylene, polytrifluoroethylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkoxyethylene copolymer, tetrafluoroethylene-ethylene copolymer. Fluorine resin such as polymer, ceramic powder, glass beads, ultra high molecular weight polyethylene, graphite, molybdenum disulfide, phenol resin, glass fiber, carbon fiber, aramid fiber, etc., at least one of these, Preferably, ceramic powder, glass beads, ultrahigh molecular weight polyethylene, graphite, molybdenum disulfide, polytetrafluoroethylene and other fluororesins, and at least one of phenolic resins, more preferably polytetrafluoroethylene. It is preferable to use a fluorocarbon resin such as La fluoroethylene.

  The present invention can be applied to the manufacture of belts that change the effective diameter of pulleys and transmit large torque, such as continuously variable transmissions for automobiles, motorcycles, and agricultural machines.

It is a principal part perspective view of the high load power transmission belt of this invention. It is a side view of the high load power transmission belt of the present invention. It is a front view of the block used for the high load power transmission belt of the present invention. It is a front view of another block used for the high load power transmission belt of the present invention. It is a side view of another belt used for the high load power transmission belt of the present invention. It is a front view of another block used for the high load power transmission belt of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High load power transmission belt 2 Block 3 Center belt 4 Elastomer 5 Core wire 6 Side surface 7 Side surface 8 Fitting groove 9 Fitting groove 10 Cover canvas 11 Upper beam part 12 Lower beam part 13 Center pillar 14 Ventilation groove 15 Concave part 16 Concave Ridge 17 ridge 18 protrusion ridge C recess D protrusion

Claims (4)

  A block formed by connecting a center belt with a core wire embedded in an elastomer, an upper beam and a lower beam with a pillar at the center, and inserting the center belt into a fitting groove surrounded by the upper and lower beams and the pillar. In the high-load transmission belt consisting of the above and the other, at least one of the front and rear surfaces of the upper and lower beams is provided with a ventilation groove that allows the fitting groove and the upper and lower surfaces of the block to communicate with each other and that allows air to flow into and out of the fitting groove High load transmission belt.   The high-load transmission belt according to claim 1, wherein a concave portion provided in the upper beam and a ventilation groove that communicates the concave portion with the inside of the fitting groove are disposed.   The high load according to claim 2, wherein a convex portion that fits into the concave portion provided in the upper beam is arranged, and the air in the concave portion is sent into the ventilation groove by the convex portion entering and exiting the concave portion while the belt is running. Transmission belt.   The high load transmission belt according to any one of claims 1 to 3, wherein the ventilation groove has a depth of 0.3 to 1.0 mm and a width of 0.3 to 1.0 mm.

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