JP2005147378A - High load transmission belt and manufacturing method of block for high load transmission belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long-life belt, preventing a covering material of a block from being broken even if high torque is applied to the block during running of the belt, or a shock is given to the block at the time of entering a pulley by dispensing with a positioning part, which is a weak point of the covering material covering an insert material. <P>SOLUTION: This high load transmission belt 1 is composed of center belts 3a, 3b and a block 2 connected to an upper beam 8 and a lower beam 9 by a pillar 10, and provided with grooves 11, 12 for inserting the center belts 3a, 3b surrounded with the upper and lower beams 8, 9 and the pillar 10, and the block 2 is formed by injection molding the covering material 21 on an insert material 20. The insert material 20 is provided with a positioning part 22 for block forming iin which the insert material 20 is exposed to only one of the upper and lower beams 8, 9. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high load transmission belt in which a block is fixed at a predetermined pitch along the longitudinal direction of a tension band, and prevents damage to the block of the high load transmission belt, thereby increasing the life of the belt. It relates to a 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. Because the side pressure from the belt increases, the belt must withstand a 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 applications where the life of conventional rubber belts is too short.

  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 material such as a bolt or a rivet.

  The required quality of the block used in such a tension transmission type high load transmission belt is the purpose of high load transmission in friction transmission as described above, so bending fatigue, wear resistance, heat resistance, rigidity It is necessary to have a good balance of properties such as impact resistance. Another important factor is not to wear the pulley.

  An example of a high load transmission belt that satisfies these requirements is disclosed in Patent Document 1. This belt uses a double-structured block in which the part where the block and pulley come into contact is coated with an insert material made of metal or the like by a resin molding material in which a rubber component is added to a phenolic resin component. It is.

  Patent Document 2 discloses that the block in the high load transmission belt as described above is formed by injection molding.

  Patent Document 3 discloses a block for a high load transmission belt in which at least a side surface of an insert material is coated with a resin, and a void formed by a through hole or a recess is formed in the insert material. It is disclosed that what is filled in the void is also included.

Japanese Patent Laid-Open No. 63-34342 JP 2000-104796 A Japanese Patent Laid-Open No. 10-47439

  When a block in which an insert material formed of metal or the like is embedded in a covering material is formed by injection molding, the insert material is set in a mold and insert molding is performed. At that time, in order to position the insert material, it is absolutely necessary to partially contact the mold. The portion of the insert material that contacts the mold is not completely covered with the resin, and the insert material is exposed on the surface of the block.

  On the other hand, since the covering material has a hole in the portion, it becomes a weak point in strength. A large torque is applied to the block while the belt is running, and an impact is also received when entering the pulley. Among them, the belt may break from the hole portion, which is a weak point existing in the covering material, and the belt reaches the end of its life early.

  The present invention solves the problems as described above, and prevents any hole in the covering material from being generated by eliminating the positioning portion of the insert material, which is a weak point of the covering material, in either of the upper and lower beams when forming the block. An object is to provide a high-load transmission belt having a long life without breaking the material.

  According to claim 1 of the present invention, there are provided a center belt in which a core wire is embedded in an elastomer, and a block having a groove for inserting the center belt surrounded by the upper and lower beams and the pillar by connecting the upper beam and the lower beam by pillars. The block is a high-load transmission belt made of an insert material formed by injection-molding a covering material, and the insert material has a block-forming positioning portion in which the insert material is exposed to only one of the upper and lower beams. And

  The high-load transmission belt according to claim 2, further comprising a positioning portion for block molding in which the insert material is exposed only to the lower beam.

  The high load transmission belt according to claim 3, wherein a space is provided in the insert material and a covering material is inserted into the space.

  Claim 4 is a block which is formed by placing an insert material in a mold and injection-molding a coating material and coating the insert material, and a high load transmission having a shape in which an upper beam and a lower beam are connected by a pillar. In the belt block manufacturing method, at least a part of either the upper beam or the lower beam of the insert material is placed in contact with the mold as a positioning portion for the mold, and the other beam contacts the mold. Without forming the gate, the gate for injecting the molten resin is arranged on the other beam side, and the block is molded while fixing the insert material to the mold by injecting the molten resin toward the beam side having the positioning portion. It is characterized by that.

  According to the fifth aspect of the present invention, only the lower beam is placed in contact with the mold, the upper beam is not brought into contact with the mold, a gate for injecting molten resin is disposed on the upper beam side, and the lower beam direction has a positioning portion. A method of manufacturing a block for a high load transmission belt, in which a block is formed while an insert material is fixed to a mold by injecting molten resin into the mold.

  According to a sixth aspect of the present invention, there is provided a method for producing a block for a high load transmission belt in which a void is provided in the insert material and a covering material enters the void.

  As in the high-load transmission belt of the present invention, the hole serving as the weak point of the covering material covering the insert material is formed by removing the positioning portion of the insert material from the mold in only one of the upper and lower beams. Since it does not occur on the side of the lost beam, even if a high torque is applied when the belt is traveling or an impact is applied when entering the pulley, the block covering material can be prevented from being destroyed, It can be a long-life belt.

  Further, the upper beam, which is particularly susceptible to a large force among the upper and lower beams, easily damages the resin, so that the effect of the present invention can be more easily achieved by eliminating the positioning portion of the insert material.

  Furthermore, the cover material can be firmly fixed to the insert material by providing the insert material with a void made of a through-hole or a recess and allowing the cover material to enter into the insert material. The effect which prevents destruction of can be strengthened.

  Further, by adopting the method for manufacturing a block for a high load transmission belt according to the present invention, the covering material is missing on either one of the upper and lower beams, the insert material is exposed, and the positioning of the insert material which becomes a weak point in terms of strength Since the part can be eliminated, it is possible to prevent the block covering material from being destroyed even if a high torque is applied when the belt is running or an impact is applied when entering the pulley. It can be a long-life belt.

  Hereinafter, the present invention will be specifically described with reference to the drawings.

  FIG. 1 is a main part perspective view showing an example of a high load transmission belt 1 according to the present invention, FIG. 2 is a side view of the main part, and FIG. 3 is a sectional view of the same. The high-load transmission belt 1 of the present invention is fixed to two center belts 3a and 3b having the same width formed by embedding a core wire 5 in a spiral shape in an elastomer 4, and the center belts 3a and 3b. A plurality of blocks 2. Both side surfaces 6 and 7 of the block 2 are inclined surfaces that engage with the V-grooves of the pulleys, and receive the power from the driven pulleys and are locked and fixed by the center belts 3a and 3b. The power of the driving pulley is transmitted to the driven pulley.

  The block 2 includes an upper beam 8 and a lower beam 9 and pillars 10 in which the central portions of the upper and lower beams 8 and 9 are connected to each other. A pair of center belts 3a and 3b are provided on both side surfaces 2a and 2b of the block 2. Grooves 11 and 12 to be fitted are formed. Further, on the groove upper surface 13 and the groove lower surface 14 in the grooves 11, 12, the ridges 17, 18 engaged with the ridges 15 provided on the upper surfaces of the center belts 3 a, 3 b and the ridges 16 provided on the lower surfaces. To be engaged.

  Further, the block 2 has a structure in which the surface of the insert material 20 is covered with a covering material 21, and the feature of the present invention is that only the lower beam 9 has a positioning portion 22 as shown in FIG. In the beam, the insert 20 is completely covered with a covering 21. Thus, the lower beam 9 has a hole in the covering material 21 at the positioning portion and the insert material 20 is exposed, whereas the upper beam 8 has no hole in the covering material 21. If the covering material 21 is perforated like the lower beam 9, it becomes a weak point and causes the covering material 21 to be damaged. However, the covering material 21 is completely covered like the upper beam 8. If the covering material 21 is covered with the material 21 and there is no hole in the covering material 21, the covering material 21 is not easily broken even when subjected to a high torque or an impact when the belt is run. Can be long.

  Here, the insert material 20 refers to a frame-like material that has almost the shape of the block 2, and for example, adding a reinforcing material such as a short fiber or a whisker to be added to the synthetic resin material. It does not mean that the insert material 20 is embedded. The insert material 20 is an insert material 20 which becomes a part that gives the side pressure resistance and bending rigidity of the block 2, and the material is a thermoplastic resin, a thermosetting resin, an aluminum alloy, a magnesium alloy ceramic, ceramics and aluminum. Examples include composite materials, carbon fiber reinforced resin, and iron.

In terms of imparting lateral pressure resistance and bending rigidity, metal materials are preferable. Among 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, and it can be said that iron is higher in strength, but for belts that rotate at high speeds, the weight of the belt greatly affects the service life, and this is advantageous in terms of weight reduction. It is preferable to use an alloy.

  In terms of weight reduction of the belt, it is preferable to use a resin material. Examples of the thermoplastic resin that can be used for the insert material 20 include polyamide resins such as nylon 46, nylon 6, nylon 66, and nylon 9T, other polyphenylene sulfide, polyether ether ketone, and the like. Fibers, polyamide fibers, cellulose, cotton, aramid fibers, polyparaphenylene benzobisoxazole fibers, polyarylate fibers, glass fibers, metal fibers, and other long fibers and short fibers can also be used.

  It is preferable to make the compounding quantity of the fiber into resin into the range of 15-110 mass%. If it is less than 15% by mass, almost no reinforcing effect can be obtained by blending the fibers. If it exceeds 110% by mass, molding becomes difficult and the hardness increases but the toughness decreases and the impact resistance of the block is reduced. Then, it is not preferable because it becomes low.

  When using a thermosetting resin, phenol resin, epoxy resin, urea resin, melamine resin, unsaturated polyester resin, diallyl phthalate resin, alkyd resin, acrylic resin, etc. can be used. It is advantageous in terms of physical properties such as strength and cost. Further, since diallyl phthalate resin is excellent in heat resistance, it can exhibit higher durability in a high temperature environment such as in an engine room of an automobile. Furthermore, the diallyl phthalate resin itself is a resin with little molding shrinkage, and the amount of shrinkage after block molding is small and more accurate dimensions can be obtained, so that it is possible to reduce noise during belt running and further to extend the life.

  Moreover, it is possible to mix | blend a fiber as a reinforcing material also to these thermosetting resins, and as a fiber, carbon fiber, polyamide fiber, cellulose, cotton, aramid fiber, polyparaphenylene benzobisoxazole fiber, polyarylate fiber And long fibers such as glass fibers and metal fibers, and short fibers. The blending amount is preferably in the range of 15 to 110% by mass, and if it is less than 15% by mass, almost no reinforcing effect is obtained by blending the fibers, and if it exceeds 110% by mass, molding becomes difficult. At the same time, the hardness increases, but the toughness decreases and the impact resistance of the block decreases, which is not preferable.

  When the covering material 21 is disposed at a predetermined location, if the insert material 20 made of a metal material that is slightly smaller than the size of the block 2 is used and the covering material 21 is almost entirely covered with the covering material 21, the covering material is partially applied. Compared to the case where the cover 21 is disposed, problems such as peeling of the covering material 21 are less likely to occur, which is a preferable form. However, even if it is the entire surface, the coating material 21 is coated at the place where it is in contact with the mold in order to fix and position the insert material 20 when coating the coating material 21 by injection molding in the manufacturing process. It becomes a location where the insert material 20 is exposed. In the present invention, the strength of the covering material 21 in the beam without the positioning portion 22 is improved by providing the positioning portion of the insert material 20 only on one of the beams.

  Furthermore, by providing a void 23 such as a through hole or a recess in the insert material 20 and allowing the coating material 21 to enter the insert material 20, the effect of physically fixing the coating material 21 to the insert material 20 is born. And the effect of preventing damage to the covering material 21 is enhanced.

  Specifically, as the covering material 21 of the block 2 that covers the insert material 20, a hard rubber having a hardness of 90 ° JIS A or higher, a hard polyurethane resin, a liquid crystal resin, a phenol resin, an epoxy resin, a polyester resin, Acrylic resin, methacrylic resin, polyamide resin, polyamideimide (PAI) resin, polyphenylene sulfide (PPS) resin, polybutylene terephthalate (PBT) resin, polyimide (PI) resin, polyethersulfone (PES) resin, polyetheretherketone A rubber such as (PEEK) resin or a synthetic resin is used. A synthetic resin such as is used. However, among these, thermosetting resins such as hard polyurethane resin, liquid crystal resin, phenol resin, and epoxy resin are inferior in impact resistance, and cracking is likely to occur. Therefore, reinforcement by the reinforcing bar 22 of the present invention is preferable.

  In the present invention, it is possible to add a fibrous reinforcing material or a whisker-like reinforcing material to the covering material 21 forming the block 2 as described above, and the fibrous reinforcing material is in the range of 15 to 40% by weight. Blend in. If it is less than 15% by weight, there is a problem that the reinforcing effect is small and the wear resistance of the block is not sufficient, and if it exceeds 40% by weight, it becomes difficult to blend into a resin or injection molding becomes difficult. Because there is a problem, it 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 them, by using a combination of nylon 46 and carbon fiber, which is a preferable example of the resin constituting the block, the carbon fiber can improve the water absorption defect of nylon 46 and greatly improve the rigidity. In addition, the wear resistance, impact resistance, and fatigue resistance of nylon 46 can be utilized. Of the carbon fibers, PAN-based carbon fibers are preferably used. Moreover, the toughness of a block improves by mix | blending an aramid fiber in combination with a carbon fiber, and abrasion resistance and impact resistance can be improved further.

  Moreover, you may mix | blend inorganic fibers, such as a zinc oxide whisker, a potassium titanate whisker, an aluminum borate whisker other than said organic fiber as said fibrous reinforcement.

  By adopting such a material structure, it has strength such as rigidity and toughness that can sufficiently withstand the side pressure received when it comes into contact with the pulley, has excellent wear resistance, and further, with respect to heat generated during friction. The power received from the pulley can be efficiently transmitted as a tensile force to the center belts 3a and 3b, and a tension transmission type high load transmission belt can be configured.

  In addition to these, the lubricity of the block 2 can be improved by mixing at least one selected from molybdenum disulfide, graphite, and fluorine-based resin. Examples of the fluororesin include polytetrafluoroethylene (PTFE), polyfluorinated ethylene propylene ether (PFPE), tetrafluoroethylene hexafluoropropylene copolymer (PFEP), polyfluorinated alkoxyethylene (PFA), and the like. .

  Moreover, the strength of the insert material 20 and the covering material 21 can be further strengthened by subjecting the insert material 20 to an adhesive treatment with an epoxy adhesive or the like.

  The lower beam 9 of the block 2 must be allowed to be bent so that the belt can be wound around the pulley, and an inclined surface is provided on at least one of the front and rear surfaces in the belt traveling direction. By providing the inclined surface, the belt can be bent without buffering between the blocks.

  Here, a manufacturing method of the block 2 will be described. The block 2 is manufactured by insert molding in which a molten resin is injection-molded in a state where the insert material 20 is disposed in the mold K in advance. As shown in FIG. 5, the insert material 20 is disposed in one mold K. The insert material 20 is supported and positioned by the mold K at the position of the positioning portion 22 on the lower beam side. Even when the mold K is closed, the upper beam of the insert material 20 is not in contact with the mold K at all, and the periphery of the insert material 20 is a cavity C for forming the covering material 21.

  Further, above the mold K, for example, a gate G for injecting the molten resin is provided near the center of the place where the insert material 20 is disposed, and the lower beam of the insert material 20 is generated by the injection power of the molten resin injected therefrom. The cavity C is filled with the molten resin while fixing the position of the insert material 20 by pressing the positioning portion 22 located on the mold K against the mold K. By cooling and demolding, the high load transmission belt block 2 having the positioning portion 22 only in the lower beam 9 and the upper beam 8 completely covered with the covering material can be manufactured.

  As the elastomer 4 of the center belts 3a and 3b, a single material such as chloroprene rubber, natural rubber, nitrile rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, or a rubber or polyurethane rubber obtained by appropriately blending them is used. Can be mentioned. 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.

  Next, in order to confirm the effect of the present invention, a belt as an example of the present invention and a belt as a comparative example were prepared and subjected to a comparative test.

  Example 1 has a shape as shown in FIG. 1 with a pitch width of 18 mm, a pitch circumference of 690 mm, and a block pitch of 3 mm. The insert material is made of a resin in which 50% by weight of glass fiber is blended with nylon 66, and is coated. As a material, a belt using a mixture of carbon fiber and phenol resin was prepared. The lower beam has a positioning portion, but the upper beam has no positioning portion. Durability tests were performed by running under the running conditions shown in Table 1. The results are shown in Table 2.

Comparative Example 1

  As Comparative Example 1, a belt having the same configuration as that of Example 1 was prepared, except that both the upper beam and the lower beam are blocks having positioning portions. Durability tests were performed by running under the running conditions shown in Table 1. The results are shown in Table 2.

  As can be seen from the results in Table 2, in Comparative Example 1, the belt life is 215 hours due to the damage of the upper beam covering material, whereas in Example 1, the belt is damaged even after traveling for 300 hours. The expected effect is obtained.

  Can be used as a belt that can extend the life of the belt due to breakage of the block mounted on the belt, and transmit a large torque by changing the effective diameter of the pulley, such as a continuously variable transmission of an automobile, a motorcycle, or an agricultural machine. Can do.

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 sectional drawing of the high load power transmission belt of this invention. It is sectional drawing of the high load power transmission belt which shows another example of this invention. It is the schematic of the place which has shape | molded the block of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High load transmission belt 2 Block 3a Center belt 3b Center belt 4 Elastomer 5 Core body 6 Side surface 7 Side surface 8 Upper beam 9 Lower beam 10 Pillar 11 Groove 12 Groove 13 Groove upper surface 14 Groove lower surface 15 Groove portion 16 Groove portion 17 Convex Ridge 18 ridge 20 insert material 21 covering material 22 positioning portion 23 void K mold G gate C cavity

Claims (6)

  It consists of a center belt with a core wire embedded in an elastomer and a block that connects the upper and lower beams with pillars and has a groove for inserting the center belt surrounded by the upper and lower beams and pillars. A high-load transmission belt comprising a material formed by injection molding, wherein the insert material has a positioning portion at the time of block molding in which the insert material is exposed to only one of the upper and lower beams.   The high-load transmission belt according to claim 1, further comprising a positioning portion at the time of block molding in which the insert material is exposed only to the lower beam.   The high-load transmission belt according to claim 1 or 2, wherein a space is provided in the insert material so that the covering material enters the space.   This is a block formed by placing the insert material in the mold, injection molding the coating material and coating the insert material, and forming a block for the high load transmission belt having a shape in which the upper beam and the lower beam are connected by a pillar. In the manufacturing method, at least a part of either the upper beam or the lower beam of the insert material is disposed in contact with the mold as a positioning portion for the mold, and the other beam is not in contact with the mold. A gate for injecting a molten resin is disposed on the other beam side, and the block is molded while fixing the insert material to the mold by injecting the molten resin toward the beam side having the positioning portion. To manufacture a block for a high load transmission belt.   Only the lower beam of the insert material is placed in contact with the mold, and the upper beam is not in contact with the mold, and a gate for injecting molten resin is placed on the upper beam side, and in the direction of the lower beam having the positioning portion. The manufacturing method of the block for high load transmission belts of Claim 4 which shape | molds a block, fixing an insert material to a metal mold | die by injecting molten resin. The manufacturing method of the block for high load transmission belts of Claim 4-5 which provided the space | gap in insert material and let the coating | coated material penetrate | invade into this space.

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