JP2008051337A - High-load transmission belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-load transmission belt in which a block continuously contacts with a pulley and which can reduce noise generated when the block intrudes into the pulley. <P>SOLUTION: This high-load transmission belt 1 is provided by installing a plurality of blocks 2 in the longitudinal direction of a center belt 3, and formed by forming projections 7 at both side ends of a front face in advancing directions of the blocks on the upper end of the contact surface 6 of the block 2 with the pulley. A recessed part 8 storing the projection 7 is formed on a rear surface in the advancing direction. The side surface 7a of the projection 7 forms a curved surface of becoming narrow in a width toward the front direction of the belt advancing direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a high-load transmission belt having a plurality of blocks mounted and fixed along the longitudinal direction of a center belt, and relates to a belt that reduces noise during belt running.

  As a belt used for a belt-type continuously variable transmission or the like, there are a center belt in which a core is embedded in an elastomer, and a belt of a type in which a plurality of blocks are mounted along the longitudinal direction of the center belt (Patent Document 1). .

  The problem with this type of belt is the amount of noise. When the block enters the pulley during running of the belt or when the block comes out of the pulley, a noise is generated that the block collides with the pulley. Unlike the conventional rubber belt, the block is also made of a hard resin material, and the sound generated by contact with the pulley is increased. A large number of blocks are mounted on the entire circumference of the belt, and sound is generated in the pitch period of the blocks as many as the number of blocks mounted while the belt goes around the pulley.

  In order to reduce pitch noise generated in a belt equipped with such a block, in Patent Document 1, noise is generated by slightly projecting and buffering a rubber center belt from the side surface of the block in contact with the pulley. A method of reducing is disclosed.

  In Patent Document 2, two types of blocks having a trapezoidal shape and an inverted trapezoidal cross-sectional shape in the longitudinal direction of the belt are alternately arranged, and two blocks adjacent to each other on a line toward the center of the pulley at a place where the block is wound around the pulley. Are overlapping. By doing so, the contact between the pulley and the block is continuously made without interruption, so that the occurrence of pitch noise can be reduced.

  Similarly, Patent Document 3 discloses that the frequency of the pitch noise is dispersed by shifting the upper and lower beams of the block in the longitudinal direction of the belt, thereby reducing the noise during belt running.

JP 60-49151 A Japanese Utility Model Publication No. 60-122052 JP 2001-90787 A

  In the belt disclosed in Patent Document 1, heat generated by friction between the center belt protruding from the block and the pulley is large, and the center belt and the block are deteriorated at an early stage, leading to a failure of the belt. There is a problem that the effect of buffering due to dripping is lost early.

  In Patent Document 2, the rear block is in contact with the adjacent block in the pulley radial direction where the front block is in contact, and the contact between the block and the pulley is not interrupted. Noise is generated when the block enters the pulley and the end first contacts the pulley.

  Similarly, in Patent Document 3, although the overall sound pressure can be suppressed by making the noise different in frequency at the top and bottom of the block and shifting the pitch, the end of the block is the pulley when the block enters the pulley. Noise also occurs when touching.

  An object of the present invention is to provide a high load transmission belt in which a block is in contact with a pulley without interruption and noise generated when the block enters the pulley can be reduced.

  In claim 1, in a center belt in which a core body is embedded in an elastomer, and a high load transmission belt in which a plurality of blocks are mounted along the longitudinal direction of the center belt, Protrusions are provided on both end portions of the front surface in the traveling direction, and a recess is formed on the rear surface in the traveling direction, and the side surface of the projection becomes narrower as it goes forward in the belt traveling direction. A curved surface is formed.

  According to a second aspect of the present invention, the position where the protrusion is formed is a high load transmission belt which is the upper end of the contact surface with the pulley of the block.

  According to a third aspect of the present invention, the tip end portions of the protrusions provided at both end portions of the block are positioned between the belt longitudinal direction line passing through the upper end of the protrusion and the belt longitudinal direction line passing through the lower end of the protrusion when viewed from the belt side surface. It is a high load transmission belt.

  According to a fourth aspect of the present invention, the belt is a high-load transmission belt that satisfies a formula of 1/4 s <h ≦ 1/2 s, where s is the thickness of the block and h is the height of the protrusion.

  A high-load transmission belt is 10% to 45% of the total height of the contact surface of the block with the pulley.

  Protrusions are provided at both ends of the front surface of the block, and recesses for accommodating the protrusions are provided on the rear surface, and the rear surface of the recesses provided on the rear surface of the block located on the inner front side of two adjacent blocks during belt running. In the state in which the protrusion of the block on the side is accommodated, the entire circumference of the pulley is in contact with the block without interruption, and the side surface of the protrusion forms a curved surface that becomes narrower as it goes forward in the belt traveling direction. Therefore, the contact of the protrusion with the pulley is a contact method in which the contact area gradually increases from the non-contact state, so that the generated noise can be extremely small.

  According to claim 2, the position where the protrusion is formed is the upper end of the contact surface of the block with the pulley, and particularly when the belt enters the pulley, the protrusion is projected on the upper portion of the block which is considered to have a large impact with the pulley first. Therefore, noise can be reduced more efficiently.

  In claim 3, there is a problem that the projection cannot be sufficiently brought into contact with the pulley and the effect of reducing noise cannot be obtained because the projection is directed upward or downward with respect to the block. It is possible to prevent the protrusions from buffering with the block when tilted with respect to the center belt.

  In claim 4, the height of the protrusion is defined by the thickness of the block, and the problem that the height of the protrusion is too low and the continuity of the block is lost, or conversely, the problem of the strength of the protrusion does not occur. It is a range.

  According to the fifth aspect, the ratio of the portion where the protrusion is formed in the entire height of the contact surface with the pulley of the block is 10 to 25%, and it is possible to obtain the effect of mitigating noise generated when entering the pulley and to transmit the belt. A sufficient area of the side surface of the block can be secured.

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

  FIG. 1 is a perspective view showing a main part of an example of a high load transmission belt 1 according to the present invention, and FIG. 2 is a side view of the main part. The high-load transmission belt 1 of the present invention includes 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 covering the surface with a cover canvas as necessary. It comprises a plurality of blocks 2 that are locked and fixed to the center belts 3a and 3b. Both side surfaces 2a and 2b 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 is composed of an upper beam 11 and a lower beam 12, and pillars 13 connecting the central portions of the upper and lower beams 11 and 12, and between the two side surfaces 2a and 2b of the block 2 and between 2c and 2d. Grooves 14 and 15 for fitting the pair of center belts 3a and 3b are formed. Further, on the groove upper surface 16 and the groove lower surface 17 in the groove portion 15, the groove portions 18, 21 that engage with the groove portions 18 provided on the groove upper surfaces of the center belts 3 a, 3 b and the groove portions 19 provided on the lower surface are provided. It is designed to engage.

  Moreover, it is preferable that the block 2 in this invention consists only of resin materials. In this way, when the block 2 in which the insert material made of metal such as aluminum alloy is not embedded is used, the belt can be reduced in weight as compared with the belt using the block in which the insert material is embedded. Although it has the advantage that the centrifugal force generated in the vehicle is small, it is suitable for high-revolution applications with relatively light loads such as motorcycles.

  In the present invention, projections 7 are provided on both ends of the front surface of the block in the traveling direction, which are part of the contact surface 6 with the pulley of the block, and a recess 8 for receiving the projection is formed on the rear surface in the traveling direction. The side surface 7a of the projection 7 forms a curved surface that becomes narrower as it goes forward in the belt traveling direction. In the example shown in the figure, the protrusion 7 is formed at the upper end of the contact surface 6. When the high load transmission belt 1 is wound around the pulley and the block 2 enters, the impact is particularly large, and noise can be reduced more efficiently.

  As shown in the figure, the protrusion 7 is accommodated in a recess 8 provided on the rear surface of the adjacent block, so that the adjacent front and rear blocks are wound around the pulley. Therefore, the blocks are overlapped so that they are in contact without interruption throughout the entire circumference of the pulley. For example, in the case where the pulley has rattling or bends, the belt wraps around the pulley. When the block enters once without interruption, the width of the pulley slightly narrows at the point where the block is interrupted, and the next block enters there to expand the narrowed width. Accordingly, the impact force between the pulley and the block at that time greatly generates noise.

  In contrast, in the belt of the present invention, the front and rear blocks overlap, so that the pulley width is expanded or reduced even if the pulley has a strength such as rattling or bending. The belt can run smoothly without running.

  Further, the side surface 7a of the protrusion 7 provided on the block forms a curved surface that becomes narrower in the belt traveling direction. Therefore, when the block enters the pulley, the projection 7 comes into contact with the pulley, but since the side surface 7a of the projection 7 that contacts the pulley is curved as described above, there is no contact with the pulley. Since the contact area is gradually increased from the state, the generated noise can be made extremely small.

  If the height h of the protrusion 7 is too low, the overlap w between adjacent blocks will be slightly or eliminated, and the blocks will not be continuous. On the other hand, if the height is too high, the protrusions 7 have an elongated shape and are easily broken. Therefore, when the thickness of the block is s and the height of the protrusion is h, it is preferable to set the height to satisfy the expression of 1 / 4s <h ≦ 1 / 2s.

  The protrusion 7 preferably protrudes straight forward in the belt traveling direction, and the tip of the protrusion 7 has an imaginary line passing through the upper end of the protrusion parallel to the belt longitudinal direction when viewed from the belt side surface and the lower end of the protrusion. It is assumed to be located between virtual lines that pass through. If the belt is facing too far upward in the direction of belt travel, the protrusions will not be able to contact the pulley sufficiently, and noise reduction will not be achieved. If it is too downward, the block will tilt with respect to the center belt. This is not preferable because the buffer between the protrusion and the block increases. The shape of the protrusion 7 may taper not only in the width direction but also in the vertical direction, but even in that case, the tip of the protrusion similarly has an imaginary line in the belt longitudinal direction passing through the upper and lower ends of the protrusion. It is preferable to be located between.

  The ratio of the portion where the protrusion 7 is formed in the entire height of the contact surface 6 with the pulley of the block is preferably 10 to 45%, and the effect of mitigating noise generated when entering the pulley can be obtained and the belt can be transmitted. A sufficient area of the side surface of the block can be secured. If it is less than 10%, the contact area with the pulley of the block is gradually increased, so that it is impossible to obtain a sufficient effect such that noise is not generated. Since the side faces are reduced, the belt transmission efficiency and the strength of the block are lowered, which is not preferable.

  The block 2 is a block basically made of a resin composition, and the resin material is formed on the surface of the block 2 made only of the resin composition and the surface of the insert material made of metal or the like in the resin composition and having the same general shape as the block. The one coated with may be used.

  In the case of a block having an insert material, the insert material is a part that gives the side pressure resistance and bending rigidity of the block 2 and includes aluminum alloy, ceramics, a composite material of ceramics and aluminum, and carbon fiber reinforcement. Examples include materials such as resin and iron.

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, and it can be said that iron is stronger in terms of strength. However, for belts that rotate at high speeds, the weight of the belt greatly affects the life of the aluminum, which is advantageous in terms of weight reduction. It is preferable to use an alloy. However, the metal material is excellent in terms of imparting side pressure resistance and bending rigidity, and it is preferable to use a block 2 in which a predetermined portion of the insert material is coated with a resin material.

  When the resin material is arranged at a predetermined location, if an insert material made of a metal material that is slightly smaller than the size of the block 2 is used to cover almost the entire surface with the resin material, the resin material is partially covered and arranged. Compared to the above, problems such as peeling of the resin material are less likely to occur, which is a preferable mode. However, even if it is the entire surface, the part where the insert material is fixed when the resin material is coated on the manufacturing process is in contact with the part where the insert material is exposed. There is no problem as long as the portion that comes into contact with the pulley and the portion where the blocks come into contact with each other are covered with resin.

  Of course, as described above, the block 2 may be made of only a resin material having no insert material as described above. When using the block 2 in which the insert material is not embedded, the weight can be reduced as compared with the belt using the block in which the insert material is embedded. However, it is suitable for applications with relatively light loads and high rotation, 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, polyphenylene sulfide (PPS) resin, polybutylene terephthalate (PBT) resin, polyimide (PI) resin, Rubbers and synthetic resins such as polyether sulfone (PES) resin and polyether ether ketone (PEEK) resin are 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. Further, it is preferable to use a resin having a low coefficient of friction, excellent wear resistance, rigidity, elasticity against bending, and a resin that does not easily break. 6-nylon is preferred.

  In addition, these resins contain cotton yarn, chemical fibers such as polyamide fibers and aramid fibers, woven fabrics made of glass fibers, metal fibers, carbon fibers, etc., fillers, whiskers, silica, inorganic materials such as calcium carbonate, etc. Made of reinforced resin.

  In the present invention, it is possible to mix a fibrous reinforcing material or a whisker-shaped reinforcing material in the resin material forming the block as described above, and the fibrous reinforcing material is blended in the range of 15 to 40% by weight. To do. 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, the resin that constitutes the block described above is a preferable example of using 4,6-nylon and carbon fiber in combination with carbon fiber to improve the water-absorbing defect of 4,6-nylon and greatly improve the rigidity. It is possible to make use of the wear resistance, impact resistance and fatigue resistance of 4,6-nylon. In addition to the organic fibers described above, inorganic fibers such as zinc oxide whisker, potassium titanate whisker, and aluminum borate whisker may be blended as the fibrous reinforcing material.

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

  A material used as the elastomer 4 of the center belt 3 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.

  The center belt 3 is provided with cover canvases 10 on both upper and lower sides, and protects the center belt 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, and for example, a form using aramid fibers in the wefts in the longitudinal direction of the belt can be mentioned. The aramid fiber may be either a para aramid fiber or a meta aramid fiber, but it is preferable to use a multifilament yarn obtained by converging an original yarn of 0.3 to 1.2 denier. 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 in the belt width direction may be filament yarn made of aramid fibers such as para-aramid fibers and meta-aramid fibers in the same manner as the weft yarns, and other polyamide fibers such as 6 nylon, 6, 6-nylon and 12 nylon. Filament yarns such as polyvinyl alcohol fiber and polyester fiber 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 solution is a mixture of an initial condensate of resorcin and formalin mixed with latex. Examples of latex used here include styrene / butadiene / pyridine terpolymers, hydrogenated nitrile rubber, chlorosulfonated polyethylene, epichlorohydrin, and the like. The latex. In addition, a glueing process, a soaking process, and a coaching process in which a rubber paste dissolved in a solvent is attached to the surface of the cover canvas 10 can also be cited as an adhesive process.

  In these adhesion treatments, the friction coefficient between the block and the center belt cover canvas can be lowered 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.

  FIG. 4 is an example of another belt, and a pair of side pillars 22 and 23 extend upward from both ends of the beam portion 21. From the upper ends of the side pillars 22 and 23, respectively, toward the center of the block 2. Extending lock portions 24 and 25 are provided so as to face each other. The beam portion 21, the side pillars 22 and 23, and the lock portions 24 and 25 form a fitting groove 20 into which the center belt 3 is fitted. The center belt 3 is inserted into the fitting groove 20 through the opening between the lock portions 24 and 25 and attached. Further, convex portions 27 are respectively provided on the side of the fitting grooves 20 of the lock portions 24 and 25, and the convex portions 27 are fitted to the concave strip portions 26 provided on the center belt 3 at a predetermined pitch. To do. As a result, the center belt 3 is not easily removed from the block 2 after being mounted.

  Even in such a form, the projection 2 and the recess 8 are provided in the block 2 in the present invention, so that noise generated when the block and the pulley come into contact with each other can be reduced.

  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 principal part side view of the high load power transmission belt of this invention. It is a principal part top view of the high load power transmission belt of this invention. It is a principal part perspective view of the high load power transmission belt which shows another example of this 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 Protrusion 7a Projection side surface 8 Fitting groove 9 Fitting groove 10 Cover canvas 11 Upper beam part 12 Lower beam part 13 Center pillar 15 Concave part 16 Concave Ridge 17 ridge 18 ridge

Claims (5)

  In a center belt in which a core body is embedded in an elastomer and a high-load transmission belt in which a plurality of blocks are mounted along the longitudinal direction of the center belt, a part of the contact surface with the pulley of the block is part of the front surface of the block in the moving direction. Each side end is provided with a protrusion, and a recess for accommodating the protrusion is formed on the rear surface in the traveling direction, and the side surface of the protrusion forms a curved surface that becomes narrower in the forward direction in the belt traveling direction. A high-load transmission belt characterized by   2. The high load transmission belt according to claim 1, wherein a position where the protrusion is formed is an upper end of a contact surface with the pulley of the block.   The front ends of the protrusions provided at both end portions of the block are located between a belt longitudinal line passing through the upper end of the protrusion and a belt longitudinal line passing through the lower end of the protrusion as viewed from the side of the belt. 2. A high load transmission belt according to 2.   The high-load transmission belt according to claim 1, wherein when the thickness of the block is s and the height of the protrusion is h, the formula 1 / 4s <h ≦ 1 / 2s is satisfied.   5. The high load transmission belt according to claim 1, wherein a portion where the protrusion is formed is 10 to 45% in a total height of a contact surface of the block with the pulley.

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