JP6322073B2 - Power transmission belt - Google Patents

Description

  The present invention relates to a power transmission belt having a configuration in which a plurality of blocks are attached along a longitudinal direction of a tension band.

  Conventionally, as a power transmission belt used in a belt-type continuously variable transmission or the like, a block belt having a structure in which a plurality of blocks are arranged in two tension bands so as to be aligned in the belt longitudinal direction has been used. The block is made of a material having high hardness and high rigidity, and plays a role of withstanding the force received from the pulley. The two tension bands are fitted and locked in two fitting grooves formed on both sides of the block in the belt width direction.

  In general block belts, for example, as shown in Patent Document 1, one protrusion is formed on each surface of the fitting groove of each block in the belt thickness direction, and this protrusion is formed in a tension band. The belt is fitted to the valley (hereinafter, this belt is referred to as a valley fitting type).

  If a valley-fitted belt is run for a long time, the contact surface (side surface) of the block will be pressed more strongly than necessary to the belt groove of the pulley depending on the locking state of the block and the tension band and running conditions, and friction force will be generated. By strengthening, the balance of the engagement state with the belt groove in the outer peripheral part and the inner peripheral part of the side surface of the block is lost, especially when the belt comes out from the belt groove of the drive pulley, There are cases where the belt cannot be pulled out smoothly. If such a state is repeated for a long time, the block swings (a phenomenon in which the block tilts with respect to the pulley radial direction).

  In the valley-fitting type belt, the tension band is bent at a valley portion which is a thin portion. That is, in the valley-fitting type belt, the position of the fitting portion between the block and the tension band and the bending position in the tension band coincide with each other in the longitudinal direction of the belt. It is easy to concentrate on the fitting part. For this reason, when the rocking of the block occurs, the fitting portion between the block and the tension band is likely to be rattled together with the sag (deterioration) of the tension band. Shaking of the fitting portion may lead to fatal failures such as tooth wear, block breakage, and belt cutting.

  Accordingly, in order to suppress the rattling of the fitting portion between the block and the tension band, for example, as in the belt described in Patent Document 2, one concave portion is formed on each side of the fitting groove of each block in the belt thickness direction. And a belt in which this valley is fitted to a peak formed in a tension band (center belt) has been proposed (hereinafter, this belt is referred to as a peak fitting type). In this mountain-fitting type belt, the position of the fitting portion between the block and the tension band and the bending position in the tension band are shifted in the belt longitudinal direction. Therefore, the bending action of the belt does not easily reach the fitting part between the block and the tension band, and the locked state is stable. Shaking of the fitting part is unlikely to occur.

Japanese Utility Model Publication No. 64-055344 Design Registration No. 1470922

  However, even with a mountain-fitting type belt, if the block swings for some reason when the load on the belt is increased and the vehicle is run for a long time, the degree is less than that of the valley-fitting type. There was a case where rattling occurred in the fitting part between a small block and a tension band. In addition, when a mountain-fitted belt is run for a long time with a high load, cracks in the internal rubber may occur at the root of the tension band, particularly on the outer peripheral surface (the surface on the side extended by bending). .

  Therefore, the present invention provides a power transmission belt capable of suppressing rattling of a fitting portion between a block and a tension band and rubber cracking of the tension band even when a load higher than before is applied. With the goal.

Means for Solving the Problems and Effects of the Invention

The power transmission belt of the present invention includes a tension band and a plurality of blocks that are arranged at a predetermined pitch along the longitudinal direction of the tension band and each have a fitting groove into which the tension band is fitted. A power transmission belt having one fitting extending in a belt width direction at a central portion in a belt longitudinal direction of an area facing the fitting groove of each block on an outer circumferential surface and an inner circumferential surface of the tension belt A peak portion is formed, and at least the outer peripheral surface and the inner peripheral surface of the tension band have a belt longitudinal direction of the fitting peak portion in a region facing the fitting groove of each block. Two fitting valleys that are located on both sides and have side surfaces on both sides in the longitudinal direction of the belt and that extend in the belt width direction are formed, and the fitting groove includes the fitting peak and the fitting valley, respectively. Recesses to fit and It characterized in that it has a part.

According to this configuration, similarly to the conventional mountain-fitting type belt, the two fitting ridges respectively formed on the outer peripheral surface and the inner peripheral surface of the tension band and the two fitting ridges formed on the fitting groove of the block The position of the fitting portion with the concave portion is shifted in the belt longitudinal direction from the bending position of the tension band (position between adjacent fitting mountain portions). Therefore, the engagement state of the fitting portion between the fitting peak portion of the tension band and the concave portion of the block can be stabilized, and swinging of the block and rattling of the fitting portion between the block and the tension band can be suppressed.
In conventional mountain-fitting type belts, the tension can be obtained only by fitting two crests formed on the outer peripheral surface and inner peripheral surface of the tension band and two concave portions formed in the fitting groove of the block. The belt and the block are fitted. Therefore, only one of the side surfaces on both sides in the belt longitudinal direction of the peak portion of the outer peripheral surface (inner peripheral surface) of the tension band becomes a power transmission surface for one block of the outer peripheral surface (inner peripheral surface) of the tension band. .
On the other hand, in the power transmission belt of the present invention, the fitting ridges formed on the outer peripheral surface of the tension band and the fitting valleys on both sides thereof are formed by the depressions formed in the fitting grooves of the block and the projections on both sides thereof. Fit into the part. Therefore, one side surface of the two fitting valley portions on the both sides in the longitudinal direction of the belt serves as a power transmission surface for one block on the outer peripheral surface of the tension band. That is, the power transmission surface for one block on the outer peripheral surface of the tension band exists at two locations separated in the belt longitudinal direction. Therefore, it is possible to disperse the stress acting on the tension band during running of the belt as compared with the conventional mountain-fitting type belt. As a result, even if the belt is subjected to a high load that causes a problem in durability with the conventional mountain-fitting type belt, it prevents a large distortion from occurring locally at the base of the fitting mountain of the tension band. It is possible to suppress the rattling of the fitting portion between the tension band and the block, and to suppress the rubber crack at the root portion of the fitting peak portion of the tension band. As a result, the power transmission capability and power transmission efficiency of the power transmission belt can be improved, and the durability at high loads can be improved.

  In the power transmission belt of the present invention, it is preferable that the tension band and each of the blocks are fixed by an adhesive at least at a fitting portion between the fitting mountain portion and the concave portion.

  According to this configuration, the tension band and each block can be more firmly fixed, and rattling of the fitting portion between the tension band and each block can be more reliably suppressed.

  In the power transmission belt of the present invention, the inner peripheral surface of the tension band has only one valley between two adjacent fitting ridges, and faces the fitting groove of each block. It is not necessary to have the two fitting valleys in the region.

According to this configuration, the inner peripheral surface of the tension band and the block are fitted only by fitting the fitting peak and the recess. Therefore, the inner peripheral surface of the tension band and the block are fitted only at a position shifted from the bending position of the tension band in the belt longitudinal direction. Therefore, the belt bending loss (power transmission loss due to bending) can be reduced as compared with the case where the fitting valley portion that fits the convex portion of the block is formed on the inner peripheral surface of the tension band. Therefore, power transmission efficiency can be further improved even when the pulley is used not only for a pulley having a large winding diameter but also for a pulley having a small winding diameter.

  In the power transmission belt of the present invention, the inner peripheral surface of the tension band includes the fitting mountain portion and the two fitting valley portions in a region facing the fitting groove of each block. May be.

According to this structure, the fitting valley part which each fits with the convex part of a block is formed in both the outer peripheral surface and inner peripheral surface of a tension belt. Therefore, not only the outer peripheral surface of the tension band but also the inner peripheral surface of the tension band, there are two power transmission surfaces for one block that are separated in the belt longitudinal direction. As a result, the stress acting on the tension band can be more dispersed compared to the case where the engagement valley portion is provided only on the outer peripheral surface of the tension band. It is possible to more reliably suppress rubber cracks at the base of the fitting peak. Therefore, durability at a higher load can be obtained as compared with the case where the fitting valley is provided only on the outer peripheral surface of the tension band.
In addition, since both the outer peripheral surface and inner peripheral surface of the tension band have fitting valleys, the contact area of the fitting part between the block and the tension band compared with the case where the tension valley is provided only on the outer peripheral surface of the tension band. Becomes larger. Therefore, the power transmission capability can be further improved.
Also, with respect to the belt longitudinal direction, the fitting portion between the tension band fitting peak and the block recess is displaced from the tension band bending position, but the tension band fitting valley and the block peak fitting portion. Corresponds to the bending position of the tension band. Therefore, the bending loss of the belt increases as compared with the case where only the outer peripheral surface of the tension band has a fitting valley. Therefore, if it is used for a pulley having a large winding diameter, high power transmission efficiency can be ensured.

  In the power transmission belt of the present invention, the block has a configuration in which an upper beam and a lower beam arranged side by side in the belt thickness direction are connected by pillars, and the fitting is performed on both sides of the pillar in the belt width direction. A groove is preferably formed.

It is a fragmentary perspective view of the belt for power transmission concerning a 1st embodiment of the present invention. It is sectional drawing of the state which wound the power transmission belt of FIG. 1 around V pulley, Comprising: It is sectional drawing cut | disconnected between the blocks. FIG. 2 is a partial side view of the power transmission belt of FIG. 1. It is a partial side view of the power transmission belt according to the second embodiment of the present invention. 6 is a partial side view of a valley fitting type belt of Comparative Example 1. FIG. It is a partial side view of the mountain fitting type belt of Comparative Examples 2-5.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described.
As shown in FIG. 1, a power transmission belt 1 (hereinafter simply referred to as a belt 1) of the present embodiment includes two endless tension bands 2 arranged in parallel, and the two tension bands 2. And a plurality of blocks 3 attached at a predetermined pitch (L) along the longitudinal direction of the belt.

  As shown in FIG. 2, the belt 1 is used by being wound around a V pulley 50 while being sandwiched between opposing surfaces 50 a of the V groove. The belt 1 is used by being wound around two V pulleys 50 (a driving pulley and a driven pulley). The angle formed by both side surfaces of the belt 1 (specifically, the block 3) is the same as the angle of the V groove of the V pulley 50. In the following description, the belt width direction, the belt thickness direction, and the belt longitudinal direction are directions shown in FIGS. In the following description, the vertical direction in FIGS. 1 to 3, the upper side of the belt 1 is the outer peripheral side of the belt 1, and the lower side of the belt 1 is the inner peripheral side of the belt 1.

  As shown in FIGS. 1 and 2, the tension band 2 includes a rubber layer 5 in which a core wire 4 is embedded in a spiral shape, and a cover canvas 6 that covers both upper and lower surfaces of the rubber layer 5. The rubber layer 5 is formed of a single material such as chloroprene rubber, nitrile rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, natural rubber, or a rubber obtained by appropriately blending these, or polyurethane rubber.

  As the core wire 4, a rope made of polyester fiber, polyamide fiber, aramid fiber, glass fiber or the like, a steel wire, or the like is used. In place of the core wire 4, a woven fabric or knitted fabric made of the above-described fibers, a metal thin plate, or the like may be embedded in the rubber layer 5.

  The cover canvas 6 is for preventing the rubber layer 5 from being worn by friction with the block 3 during belt running. The cover canvas 6 is a woven fabric such as plain weave, twill weave or satin weave, and as its fiber material, aramid fiber, polyamide fiber, polyester fiber or the like is used.

  As shown in FIGS. 1 and 3, on the upper surface (outer peripheral surface) 2a of the tension band 2, a large number of peak portions 21 and 22 extending in the belt width direction are formed side by side at a predetermined pitch in the belt longitudinal direction. . The peaks 21 and peaks 22 are alternately formed in the belt longitudinal direction. A valley 23 extending in the belt width direction is formed between the adjacent peaks 21 and 22. The arrangement pitch of the crests 21 and 22 is half of the arrangement pitch (L) of the plurality of blocks 3.

When viewed from the belt width direction, the tip portions of the peak portions 21 and 22 and the bottom of the valley portion 23 are formed in an arc shape. In the present embodiment, the shapes of the ridges 21 and the ridges 22 are substantially the same, but the shapes of the ridges 21 and the ridges 22 (for example, the length in the longitudinal direction of the belt, the curvature of the tip, etc.) are different. Good. However, the projection height of the peak portion 21 and the crests 2 2 is preferably the same. For example, when the minimum thickness of the belt 1 is 1.5 to 3.5 mm, it is preferable that the protruding heights of the peaks 21 and 22 (depths of the valleys 23) are 0.5 mm or more.

  On the lower surface (inner peripheral surface) 2b of the tension band 2, a large number of ridges 24 extending in the belt width direction are formed side by side at a predetermined pitch in the belt longitudinal direction. A valley 25 extending in the belt width direction is formed between the adjacent peaks 24. The arrangement pitch of the plurality of peak portions 24 is the same as the arrangement pitch (L) of the plurality of blocks 3. When viewed from the belt width direction, the tip of the peak portion 24 is formed in an arc shape, and the bottom of the valley portion 25 is formed in a substantially flat shape. The preferable range of the protruding height of the peak portion 24 (depth of the valley portion 25) is the same as that of the peak portions 21 and 22.

  As shown in FIGS. 1 and 3, the plurality of blocks 3 have the same shape and are arranged with a predetermined gap along the longitudinal direction of the belt. Two fitting grooves 10 into which the two tension bands 2 are fitted are formed on both sides of the block 3 in the belt width direction. In the present embodiment, the side surface of the tension band 2 fitted in the fitting groove 10 is substantially flush with the side surface of the block 3, but is provided at a position slightly deeper than the side surface of the block 3. May be.

  The block 3 includes an upper beam 7 and a lower beam 8 arranged in the belt thickness direction, and a pillar 9 that connects the central portions of the upper and lower beams 7 and 8 in the belt width direction. Both sides of the upper half of the block 3 (upper beam 7 and part of the pillar 9) in the belt longitudinal direction are substantially orthogonal to the belt longitudinal direction. Further, both sides of the belt longitudinal direction of the lower half of the block 3 (the remaining portions of the lower beam 8 and the pillar 9) are arranged in the belt longitudinal direction so that the distance between both surfaces becomes narrower toward the lower side (inner peripheral side). Inclined with respect to the orthogonal direction.

  The two fitting grooves 10 are formed on both sides of the pillar 9 in the belt width direction. The fitting groove 10 is formed by the lower surface 10 a of the upper beam 7 (hereinafter referred to as the groove upper surface 10 a), the upper surface 10 b of the lower beam 8 (hereinafter referred to as the groove lower surface 10 b), and the side surface of the pillar 9. The groove upper surface 10 a faces the upper surface (outer peripheral surface) 2 a of the tension band 2, and the groove lower surface 10 b faces the lower surface (inner peripheral surface) 2 b of the tension band 2.

  A concave portion 31 extending in the belt width direction is formed at the center of the groove upper surface 10a in the belt longitudinal direction. In addition, two convex portions 32 extending in the belt width direction are formed on both sides in the belt longitudinal direction of the concave portion 31 of the groove upper surface 10a. The concave portion 31 and the convex portion 32 of the groove upper surface 10 a are fitted into the peak portion 21 and the valley portion 23 of the upper surface 2 a of the tension band 2, respectively. Therefore, on the upper surface 2 a of the tension band 2, a peak portion 21 and two valley portions 23 are formed in a region facing the fitting groove 10 of each block 3. Of the peaks 21 and 22 on the upper surface 2a of the tension band 2, only the peaks 21 correspond to the fitting peaks of the present invention, and the peaks 22 do not correspond to the fitting peaks of the present invention.

  A concave portion 33 extending in the belt width direction is formed in the central portion of the groove lower surface 10b in the belt longitudinal direction. The concave portion 33 of the groove lower surface 10 b is fitted to the peak portion 24 of the lower surface 2 b of the tension band 2. On the lower surface 2b of the tension band 2, a crest 24 is formed in a region facing the fitting groove 10 of each block 3, but no trough is formed as in the upper surface 2a. The peak portion 24 corresponds to the fitting peak portion of the present invention.

  In this way, each block 3 and the tension band 2 are locked by fitting the concave portion 31 and the peak portion 21, the convex portion 32 and the valley portion 23, and the concave portion 33 and the peak portion 24.

  The depth of the concave portion 31 on the groove upper surface 10a (the protruding height of the convex portion 32) is the same as the protruding height of the peak portion 21 (the depth of the valley portion 23) on the outer peripheral surface 2a of the tension band 2. The depth of the recess 33 on the groove lower surface 10 b is the same as the protruding height of the crest 24 on the inner peripheral surface 2 b of the tension band 2.

Here, the maximum length in the belt thickness direction at the fitting portion between the block 3 and the tension band 2 is defined as the maximum mating length _D1MAX, and the minimum length in the belt thickness direction is defined as the minimum mating length _D1MIN . The maximum fitting length _D1MAX is the length from the bottom of the recess 31 on the groove upper surface 10a to the bottom of the recess 33 on the groove lower surface 10b. The minimum fitting length _D1MIN is the length from the tip of the convex portion 32 of the groove upper surface 10a to the groove lower surface 10b. In a state in which the tension band 2 and the block 3 is not engaged, a length corresponding to the fitting maximum length D1 _MAX of the fitting groove 10 of the block 3, the maximum of the fitting tension band 2 to the length D1 _MAX It is slightly smaller than the corresponding length. In the state where the tension band 2 and the block 3 are not fitted, the length corresponding to the minimum fitting length D1 _MIN of the fitting groove 10 of the block 3 is the minimum fitting length D1 of the tension band 2. It is slightly smaller than the length corresponding to _MIN . Therefore, the tension band 2 is fitted in the fitting groove 10 of the block 3 in a state where it is slightly compressed in the belt thickness direction. Thereby, the block 3 and the tension | tensile_strength band 2 can be latched more firmly.

  Further, the block 3 and the tension band 2 are fixed by an adhesive at least in a fitting portion between the concave portion 31 and the mountain portion 21 and a fitting portion between the concave portion 33 and the mountain portion 24. Thereby, the block 3 and the tension | tensile_strength band 2 can be fixed more firmly. Fixing the fitting portion between the concave portion 31 and the mountain portion 21 with an adhesive means at least the bottom portion of the concave portion 31 (the arc-shaped portion in this embodiment) and the tip portion of the mountain portion 21 via an adhesive. A fixed state. In addition to the above locations, the fitting portions of the convex portions 32 and the valley portions 23 may be fixed by an adhesive, and the portions on both sides in the belt longitudinal direction of the concave portions 33 on the groove lower surface 10b and a portion of the valley portions 25 May be fixed. Further, the entire range of the fitting groove 10 in contact with the tension band 2 may be fixed to the tension band 2 with an adhesive.

  Although the block 3 may be comprised only by the resin composition, it may be comprised by what coat | covered the resin composition on the surface of the insert material formed with metals, ceramics, etc., such as aluminum alloys. As the resin composition, a synthetic resin blended with a reinforcing material, a friction reducing material, or the like is used.

  Synthetic resins constituting the resin composition include liquid crystal resins, phenol resins, epoxy resins, polyester resins, acrylic resins, methacrylic resins, polyamide resins, polyamideimide (PAI) resins, polyphenylene sulfide (PPS) resins, polybutylenes. Examples include terephthalate (PBT) resin, polyimide (PI) resin, polyether sulfone (PES) resin, and polyether ether ketone (PEEK) resin. Among these, a thermoplastic resin, particularly a polyamide resin is preferable. In place of the synthetic resin, hard rubber having a JIS-A hardness of 90 ° or more, or hard polyurethane may be used.

  Examples of the reinforcing material blended in the resin composition include fibrous reinforcing materials such as aramid fiber, carbon fiber, glass fiber, polyamide fiber, and polyester fiber, and whisker-like reinforcement such as zinc oxide whisker and potassium titanate whisker. Materials. By blending these reinforcing materials, the strength such as the bending rigidity of the block 3 can be increased, and when the whisker-like reinforcing material is used, wear of the block 3 due to friction with the pulley can be suppressed. . When a whisker-like reinforcing material is used, a portion (fitting) of the block 3 in contact with the tension band 2 in order to prevent the tension band 2 from being worn by the whisker-like reinforcing material in the portion in contact with the block 3. It is preferable not to add a whisker-like reinforcing material to the resin composition constituting the periphery of the groove 10.

  Examples of the friction reducing material blended in the resin composition include fluorine resins such as polytetrafluoroethylene (PTFE) and polyfluorinated ethylene propylene ether (PFPE), molybdenum disulfide, and graphite. By blending such a friction reducing material, the friction coefficient between the block 3 and the pulley is reduced, so that wear of the block 3 can be suppressed.

  The belt 1 of the present embodiment described above has the following characteristics.

The belt 1 of the present embodiment has crests (fitting crests) 21 and 24 at the same position in the longitudinal direction of the belt 2 on the outer circumferential surface 2a and the inner circumferential surface 2b of the tension band 2, and these two crests 21 , 24 are fitted in the recesses 31, 33 formed in the fitting groove 10 of the block 3, respectively. When a part of the belt 1 is wound around the V pulley 50 and bent, the tension band 2 is bent at a portion between the bottom of the valley portion 23 and the bottom of the valley portion 25 which is a thin portion. Accordingly, the position of the fitting portion between the ridges 21 and 24 of the tension band 2 and the recesses 31 and 33 of the block 3 is the longitudinal direction of the belt from the bending position of the tension band 2, as in the conventional ridge fitting type belt. It is shifted to. Therefore, the locking state of the fitting portion between the peak portions 21 and 24 of the tension band 2 and the concave portions 31 and 33 of the block 3 can be stabilized, and the swinging of the block 3 and the fitting portion between the block 3 and the tension band 2 can be stabilized. It can suppress rattling.

  In conventional mountain-fitting type belts, tension can be obtained only by fitting two crests formed on the outer peripheral surface and inner peripheral surface of the tension band and two concave portions formed in the fitting groove of the block. The belt and the block are fitted. Therefore, only one of the side surfaces on both sides in the belt longitudinal direction of the peak portion of the outer peripheral surface (inner peripheral surface) of the tension band becomes a power transmission surface for one block of the outer peripheral surface (inner peripheral surface) of the tension band. .

  On the other hand, in the belt 1 of the present embodiment, the crests 21 formed on the outer peripheral surface 2 a of the tension band 2 and the troughs (fitting troughs) 23 on both sides thereof are formed in the fitting groove 10 of the block 3. It fits into the recessed part 31 and the convex part 32 of the both sides. Therefore, for example, when the belt 1 travels in the left direction in FIG. 3, the tension when the areas A <b> 1 and A <b> 2 indicated by the thick lines in FIG. 3 on the outer peripheral surface 2 a of the tension band 2 are engaged with the drive pulley 50. It becomes a power transmission surface for one block 3 (the block 3 at the left end in FIG. 3) on the outer peripheral surface 2a of the belt 2. Thus, the power transmission surface for one block 3 on the outer peripheral surface 2a of the tension band 2 exists at two locations separated in the belt longitudinal direction. Therefore, the stress acting on the tension band 2 during belt running can be dispersed as compared with a conventional mountain-fitting type belt. As a result, even if a high load that causes a problem in durability is applied to the belt 1 in the conventional mountain-fitting type belt, a large strain is locally generated at the root portion of the peak portion 21 of the tension band 2. Can be prevented. Therefore, rattling of the fitting portion between the tension band 2 and the block 3 can be suppressed, and rubber cracks at the root portion of the peak portion 21 of the tension band 2 can be suppressed. As a result, the power transmission capability and power transmission efficiency of the belt 1 can be improved, and durability at high loads can be improved.

  3 shows one block 3 (the leftmost block in FIG. 3) on the inner peripheral surface 2b of the tension band 2 when engaged with the drive pulley 50 when the belt 1 travels in the left direction in FIG. The power transmission surface B for 3) is displayed.

  As described above, in order to disperse the stress acting on the tension band 2, the protruding heights (depths of the valley parts 23) of the peaks 21 and 22 on the outer peripheral surface 2a of the tension band 2 are 0.5 mm or more. It is preferable. If the protruding height is smaller than 0.5 mm, it is difficult to secure the power transmission surface on the outer peripheral surface 2a of the tension band 2 by dispersing it in the longitudinal direction of the belt, and the stress acting on the tension band 2 can be dispersed. Because it becomes difficult. Moreover, the stress which acts on the tension | tensile_strength band 2 can be disperse | distributed with sufficient balance by making the protrusion height of the peak part 21 and the peak part 24 the same.

In the present embodiment, the inner peripheral surface 2b of the tension band 2 has only one trough 25 between two adjacent crests (fitting crests) 24, and the crest 24, the recess 33, The inner peripheral surface 2b of the tension band 2 and the block 3 are fitted with each other. Therefore, the inner peripheral surface 2b of the tension band 2 and the block 3 are fitted only at a position that is different from the bending position of the tension band 2 in the belt longitudinal direction. Therefore, as in the second embodiment to be described later, compared to the case where a trough (fitting trough) 127 that fits the crest 134 of the block 103 is formed on the inner peripheral surface 102b of the tension band 102, The bending loss of the belt 1 (power transmission loss due to bending) can be reduced. Therefore, the power transmission efficiency can be further improved not only for the V pulley 50 having a large winding diameter but also for the V pulley 50 having a small winding diameter.

  In the present embodiment, the tension band 2 and each block 3 are fixed by an adhesive at least in the fitting portion between the peak portion 21 and the concave portion 31 and in the fitting portion between the peak portion 24 and the concave portion 33. ing. Therefore, the tension band 2 and each block 3 can be more firmly fixed, and rattling of the fitting portion between the tension band 2 and each block 3 can be more reliably suppressed.

Second Embodiment
Hereinafter, a second embodiment of the present invention will be described. In addition, about the thing which has the structure similar to the said 1st Embodiment, the description is abbreviate | omitted suitably using the same code | symbol.
As shown in FIG. 4, the power transmission belt 101 (hereinafter simply referred to as the belt 101) of the present embodiment includes the configuration of the lower surface (inner peripheral surface) 102 b of the tension band 102 and the groove of the fitting groove 110 of the block 103. The configuration of the lower surface 110b is different from the belt 1 of the first embodiment, and the other configurations are the same as those of the belt 1 of the first embodiment.

  The tension band 102 includes a rubber layer 105 in which the core wire 4 is embedded, and a cover canvas 6 that covers both the upper and lower surfaces of the rubber layer 105. On the lower surface (inner peripheral surface) 102b of the tension band 102, a large number of peak portions 124, 126 extending in the belt width direction are formed side by side at a predetermined pitch in the belt longitudinal direction. The mountain portions 126 and the mountain portions 124 are alternately formed in the belt longitudinal direction. A valley 127 extending in the belt width direction is formed between the adjacent peaks 124 and 126. The arrangement pitch of the crest 126 and the crest 124 is half of the arrangement pitch (L) of the plurality of blocks 103.

  When viewed from the belt width direction, the tip portions of the peak portions 124 and 126 and the bottom of the valley portion 127 are formed in an arc shape. The mountain portion 126 is formed to be slightly tapered from the mountain portion 124. Thus, in this embodiment, although the shape of the peak part 124 and the peak part 126 is slightly different, it may be the same and may differ from each other in a different form from this embodiment. Due to the different shapes of the peak portion 124 and the peak portion 126, two adjacent valley portions 127 are symmetrical with respect to the belt longitudinal direction. The suitable range of the protrusion height (depth of the trough 127) of the peaks 124 and 126 is the same as that of the peaks 21, 22, and 24 of the first embodiment.

  The block 103 includes an upper beam 7, a lower beam 108, and pillars 9 that connect them, and has two fitting grooves 110 on both sides of the pillar 9 in the belt width direction. A recess 133 extending in the belt width direction is formed at the center of the groove lower surface 110b of the fitting groove 110 in the belt longitudinal direction. Further, two convex portions 134 extending in the belt width direction are formed on both sides of the concave portion 133 of the groove lower surface 110b in the belt longitudinal direction. The concave portion 133 and the convex portion 134 of the groove lower surface 110b are fitted into the peak portion 124 and the valley portion 127 of the lower surface 102b of the tension band 102, respectively. Therefore, on the lower surface (inner peripheral surface) 102b of the tension band 102, a peak portion 126 and two valley portions 127 are formed in a region facing the fitting groove 110 of each block 103. Of the crests 124 and 126 on the lower surface 102b of the tension band 102, only the crest 124 corresponds to the fitting crest of the present invention, and the crest 126 does not correspond to the fitting crest of the present invention.

  In this way, each block 103 and the tension band 102 are locked by fitting the concave portion 31 and the peak portion 21, the convex portion 32 and the valley portion 23, the concave portion 133 and the peak portion 124, and the convex portion 134 and the valley portion 127. ing.

  The depth of the concave portion 133 (the protruding height of the convex portion 134) of the groove lower surface 110b is the same as the protruding height (the depth of the valley portion 127) of the peak portion 124 of the inner peripheral surface 102b of the tension band 102.

The block 103 and the maximum length of the belt thickness direction at the fitting portion between the tension band 102 and the fitting maximum length D2 _MAX, the minimum length of the belt thickness direction and fitted minimum length D2 _MIN. Fitting maximum length D2 _MAX is the length from the bottom of the recess 31 of the groove upper surface 10a to the bottom of the recess 133 of the groove bottom surface 110b. The minimum fitting length _D2MIN is the length from the tip of the convex portion 32 on the groove upper surface 10a to the tip of the convex portion 134 on the groove lower surface 110b.

In a state in which the tension band 102 and the block 103 is not engaged, a length corresponding to the fitting maximum length D2 _MAX of the fitting groove 110 of the block 103, the fitting maximum length D2 _MAX tension zone 102 It is slightly smaller than the corresponding length. In the state where the tension band 102 and the block 103 are not fitted, the length corresponding to the minimum fitting length D2 _MIN of the fitting groove 110 of the block 103 is the minimum fitting length D2 of the tension band 102. It is slightly smaller than the length corresponding to _MIN . Therefore, the tension band 102 is fitted in the fitting groove 110 of the block 103 in a state where it is slightly compressed in the belt thickness direction. Thereby, the block 103 and the tension | tensile_strength band 102 can be latched more firmly.

  Although not shown in FIG. 4, in the state where the tension band 102 and the block 103 are not fitted, the radius of curvature of the bottom of the trough 127 of the tension band 2 is the tip of the convex part 134 of the block 103. Is slightly larger than the radius of curvature. Thereby, when the belt 1 bends, the stress which acts on the trough part 127 of the tension band 102 is relieved, and the heat generation of the internal rubber of the tension band 102 can be suppressed. Since the movement of the block 103 with respect to the tension band 102 can be suppressed by suppressing the heat generation, the wear of the tension band 102 can be suppressed. This configuration is particularly effective when used for the V pulley 50 having a small winding diameter because the bending angle of the tension band 102 becomes large. In the state where the tension band 102 and the block 103 are not fitted, the curvature radius of the bottom of the trough 127 of the tension band 2 is the same as the curvature radius of the tip of the convex part 134 of the block 103. Good.

  Further, the block 103 and the tension band 102 are fixed by an adhesive at least in a fitting portion between the concave portion 31 and the mountain portion 21 and a fitting portion between the concave portion 133 and the mountain portion 124. Thereby, the block 3 and the tension | tensile_strength band 2 can be fixed more firmly. In addition to the above locations, at least one of the fitting part between the convex part 32 and the valley part 23 and the fitting part between the convex part 134 and the valley part 127 may be fixed with an adhesive.

  The belt 101 of the present embodiment described above has the following characteristics.

  Similar to the belt 1 of the first embodiment, the belt 101 is configured such that the position of the fitting portion between the ridges 21 and 124 of the tension band 102 and the recesses 31 and 133 of the block 3 is longer than the bending position of the tension band 102. Since the displacement is in the direction, it is possible to stabilize the locking state of the fitting portion between the ridges 21 and 124 of the tension band 102 and the recesses 31 and 133 of the block 3, and the rocking of the block 3 and the block 3 and the tension band 2. The rattling of the fitting part can be suppressed.

Further, similarly to the belt 1 of the first embodiment, the power transmission surface for one block 3 on the outer peripheral surface 2a of the tension band 102 exists at two locations separated in the belt longitudinal direction, and thus acts on the tension band 2. It is possible to prevent stress from being dispersed and to prevent local large distortion from occurring at the root portion of the peak portion 21 of the tension band 2, rattling of the fitting portion between the tension band 2 and the block 3 and the peak of the tension band 2. Rubber cracks at the base of the portion 21 can be suppressed.
In the present embodiment, fitting troughs 23 and 127 are formed on the outer peripheral surface 2a and the inner peripheral surface 102b of the tension band 102 to fit the convex portions 32 and 134 of the block 103, respectively. Therefore, for example, when the belt 1 travels in the left direction in FIG. 4, the regions C <b> 1 and C <b> 2 indicated by the thick lines in FIG. 4 on the inner peripheral surface 102 b of the tension band 102 are engaged with the drive pulley 50. It becomes a power transmission surface for one block 103 (the block 103 at the left end in FIG. 4) on the inner peripheral surface 102b of the tension band 102. Therefore, not only on the outer peripheral surface 2a of the tension band 102 but also on the inner peripheral surface 102b of the tension band 102, there are two power transmission surfaces for one block 103 separated in the belt longitudinal direction. Thereby, like the belt 1 of 1st Embodiment, compared with the case where the inner peripheral surface 2b of the tension | tensile_strength band 2 and the block 3 are fitted only by fitting with the fitting peak part 24 and the recessed part 33. FIG. The stress acting on the tension band 102 can be further dispersed. Therefore, the rattling of the fitting portion between the tension band 102 and the block 103 can be more reliably suppressed, and the rubber crack at the root portion of the peak portion 21 of the tension band 102 can be more reliably suppressed. Therefore, durability at a higher load can be obtained as compared with the belt 1 of the first embodiment.

  Moreover, since the contact area of the fitting part of the block 103 and the tension | tensile_strength band 102 becomes large compared with the belt 1 of 1st Embodiment, power transmission capability can be improved more.

  Further, in the present embodiment, with respect to the longitudinal direction of the belt, the fitting portions between the ridges 21 and 124 of the tension band 102 and the recesses 31 and 133 of the block 103 deviate from the bending position of the tension band 102. The fitting portions between the valley portions 23 and 127 and the convex portions 32 and 134 of the block 103 coincide with the bending position of the tension band 102. Therefore, the bending loss of the belt 101 becomes larger than that of the belt 1 of the first embodiment. Therefore, if it is used for a pulley having a large winding diameter, high power transmission efficiency can be ensured.

  Since the belt 1 of the first embodiment and the belt 101 of the second embodiment have the above characteristic differences, the belt 1 of the first embodiment has a small-diameter pulley (winding in a low load to a medium load region). The belt 101 of the second embodiment is suitable for use with a large-diameter pulley (V-pulley with a large winding diameter) in a low load to high-load region. Yes. Although the belt 1 of the first embodiment can be applied to a large-diameter pulley, the belt 101 of the second embodiment is less in power transmission efficiency than the first embodiment, but has a power transmission capability than the first embodiment. Since it is high, it is preferable to apply the belt 101 of the second embodiment to the large-diameter pulley.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above-described embodiments, and various modifications can be made as long as they are described in the claims.

  In the first and second embodiments, at least a part of the fitting portion between the tension bands 2 and 102 and the blocks 3 and 103 is fixed with an adhesive. However, the fixing with the adhesive may not be performed.

  In the first and second embodiments, when viewed from the belt width direction, the tip portions of the peak portions 21, 22, 24, 124, 126 of the tension bands 2, 102 are formed in an arc shape, but are flat. It may be formed. In the first and second embodiments, the bottoms of the valleys 23 and 127 of the tension bands 2 and 102 are formed in an arc shape when viewed from the belt width direction, but may be formed in a flat shape. Good.

  In the first and second embodiments, the belts 1 and 101 are composed of two tension bands 2 and 102 and a plurality of blocks 3 and 103. However, the belt of the present invention has one tension band and a plurality of blocks. It may be composed of blocks. In this case, the tension band is fitted into the fitting grooves formed on the side surface or the upper and lower surfaces of the block. The belt of the present invention may be composed of three or more tension bands and a plurality of blocks.

  Next, specific examples and comparative examples of the present invention will be described.

<Example 1>
The belt of Example 1 has the same form as the belt 1 of the first embodiment shown in FIGS. The rubber layer (5) of the tension band (2) of the belt of Example 1 was formed of hydrogenated nitrile rubber. For the core wire (4), a twisted cord made of aramid fiber and having a diameter of 0.7 mm was used. For the cover canvas (6), a 0.9 mm thick canvas twilled with weft yarns of the aramid fibers (belt longitudinal direction) and warp yarns of the polyamide fibers (belt width direction) was used. Further, the block (3) has a structure in which carbon fiber is blended as a reinforcing material in a resin composition containing a polyamide resin as a main component.

  The fitting part between the block and the tension band was bonded by the following procedure. First, the molded and vulcanized tension band was dipped with an isocyanate-based adhesive composed of 50% by weight of a polyisocyanate compound and 50% by weight of toluene. Thereafter, the tension band was naturally dried at room temperature (15 to 25 ° C.) for 30 minutes, assembled to a plurality of blocks to form a belt, and then oven-dried at a tank temperature of 150 ° C. for 30 minutes. Thereby, all the fitting parts of the block and the tension band were bonded with an adhesive.

  The protruding heights (depths of the valleys (23, 25)) of all the peaks (21, 22, 24) on the outer peripheral surface and inner peripheral surface of the tension band were 0.7 mm. The depths of all the recesses (31, 33) in the fitting groove of the block have the same dimensions. The block thickness (maximum length in the belt longitudinal direction of the block) was 3 mm, the belt circumferential length on the core wire pitch line was 612 mm, and the belt width on the core wire pitch line was 25 mm. Other dimensions of the belt of Example 1 are shown in Table 1.

  In addition, the “minimum fitting groove interval” and “maximum fitting groove interval” of the blocks in Table 1 are the minimum and maximum intervals in the belt thickness direction of the fitting grooves of the block in a state where no tension band is attached. That's it. Further, the “minimum thickness” and “maximum thickness” of the tension band in Table 1 are the minimum thickness of the range (opposite range) in which the tension band is not attached to the block. It is the maximum thickness.

<Example 2>
The belt of Example 2 has the same form as the belt 101 of the second embodiment shown in FIG. The material of the belt is the same as that of Example 1. Moreover, the fitting part of the block and the tension | tensile_strength was adhere | attached with the adhesive agent similarly to the belt of Example 1. The protruding height (depth of valley), block thickness, belt circumferential length, and belt width of the tension band of Example 2 are the same as those of the belt of Example 1, and other dimensions are shown in Table 1. As shown.

<Comparative Example 1>
The belt of Comparative Example 1 is a valley fitting type belt 81 shown in FIG. The material of the belt is the same as that of Example 1. The belt of Comparative Example 1 is not subjected to the bonding process of the fitting portion between the block 83 and the tension band 82. The protruding height (depth of valley), block thickness, belt circumferential length, and belt width of the tension band of Comparative Example 1 are the same as those of the belt of Example 1, and other dimensions are shown in Table 1. As shown. The tension band is fitted to the block while being slightly compressed in the belt thickness direction. In Table 1, “minimum gap between fitting grooves” and “minimum thickness” of the tension band in the block of Comparative Example 1 are lengths corresponding to D3 _MIN in FIG. The “maximum fitting groove interval” of the block and the “maximum thickness” of the tension band are lengths corresponding to D3 _MAX in FIG.

<Comparative example 2>
The belt of Comparative Example 2 is a mountain-fitting type belt 91 shown in FIG. The material of the belt is the same as that of Example 1. The belt of Comparative Example 2 is not subjected to the bonding treatment of the fitting portion between the block 93 and the tension band 92. The protruding height (depth of the valley), the block thickness, the belt circumferential length, and the belt width of the tension band of Comparative Example 2 are the same as those of the belt of Example 1, and other dimensions are shown in Table 1. As shown. The tension band is fitted to the block while being slightly compressed in the belt thickness direction. In Table 1, “minimum gap between fitting grooves” and “minimum thickness” of the tension band in the block of Comparative Example 2 are lengths corresponding to D4 _MIN in FIG. The “maximum fitting groove interval” of the block and the “maximum thickness” of the tension band are lengths corresponding to D4 _MAX in FIG.

<Comparative Examples 3 and 4>
The belts of Comparative Examples 3 and 4 are belts having the same configuration as that of Comparative Example 2, and the fitting portion between the block and the tension band was bonded with an adhesive in the same procedure as in Example 1.

<Comparative Example 5>
As shown in Table 1, the belt of Comparative Example 5 has a block height different from that of Comparative Examples 3 and 4, but the other configurations are the same as those of Comparative Examples 3 and 4.

The durability test of the belts of Examples 1 and 2 and Comparative Examples 1 to 5 described above was performed.
Each belt was wound around the drive pulley and the driven pulley, the axial load of the driven pulley was set to the value shown in Table 1, and the drive pulley was rotated in an atmosphere of 100 ° C. Note that the belt tension in the stationary state is half the value of the axial load. The power value of the drive motor of the drive pulley that determines the load on the belt was set to the value shown in Table 1, and the drive pulley was rotated at a setting where the rotational speed was 6000 rpm when the axial load of the driven pulley was unloaded. The distance between the shafts of both pulleys is not fixed so that the axial load of the driven pulley is constant during traveling. The axial load of the driven pulley was set to such a value that the belt did not slip with respect to the load based on the power value of the drive motor. The angle of the V groove of the driving pulley and the driven pulley was 26 °, and the belt winding diameter was a value shown in Table 1.

  After running the belt for 250 hours, evaluate the engagement state between the block and the tension band, confirm whether the tension band is damaged (wear, crack), and change the width of the upper beam of the block (length in the belt width direction) The amount (amount of wear) was measured.

  Evaluation of the fitting state of the blocks and the tension bands of Examples 1 and 2 and Comparative Examples 1 to 5 is as follows. In Examples 1 and 2 and Comparative Example 3, there was almost no backlash of the block in the longitudinal direction of the belt (O rating in Table 1). In Comparative Examples 2, 4, and 5, there was a slight rattling of the block, but even when the block was moved relative to the tension band, no gap was found between the fitting groove and the tension band (in Table 1). (△ evaluation). In Comparative Example 1, a looseness was clearly generated in the fitting portion between the block and the tension band, and a gap was confirmed between the fitting groove and the tension band (X evaluation in Table 1).

  About the damage state of the tension band of Examples 1, 2 and Comparative Examples 1-5, it is as follows. In Examples 1 and 2 and Comparative Example 3, the tension band was not damaged. In Comparative Example 1, the cover canvas on the inner peripheral side of the tension band was worn away. In Comparative Example 2, the cover canvas on the inner peripheral side of the tension band was worn. In Comparative Example 4, two small cracks were confirmed at the roots of the peaks on the outer peripheral surface of the tension band. In Comparative Example 5, four small cracks were confirmed at the roots of the peaks on the outer peripheral surface of the tension band.

  Further, the amount of change (amount of wear) in the width of the upper beam of the block is as shown in Table 1. In general, the functionally acceptable range for power transmission is 0.20 mm or less, and the best range that is recognized as having no wear is 0.05 mm or less.

  Table 1 also shows the determination results as to whether or not the belt can be allowed as a power transmission belt based on the fitting state of the block and the tension band, the damage state of the tension band, and the wear amount of the upper beam width of the block. ◯ in the determination results of Table 1 indicates that it is good, Δ indicates that it is within an allowable range, and × indicates that it is not allowable.

As is clear from the test results in Table 1, the belt of the mountain-fitting type in which the fitting portion between the block and the tension band is bonded, the power of the drive motor is relatively low at 20 kW. Although rattling or the like can be suppressed (Comparative Example 3), when the power value of the drive motor reaches 30 kW, rattling of the fitting portion or cracking of the tension band occurs (Comparative Examples 4 and 5).
In contrast, the belt of Example 1 can suppress rattling of the fitting portion and damage to the tension band even when the power value of the drive motor is 30 kW. Further, the belt of Example 2 can suppress rattling of the fitting portion and damage to the tension band even at 40 kW, which is a higher power value of the drive motor.

DESCRIPTION OF SYMBOLS 1,101 Power transmission belt 2, 102 Tension band 2a Tension band outer peripheral surface 2b, 102b Tension band inner peripheral surface 3, 103 Block 7 Upper beam 8, 108 Lower beam 9 Pillar 10 Fitting groove 10a Groove upper surface 10b Groove Lower surface 21, 24, 124 Mountain (fitting mountain)
22, 126 Mountain part 23, 127 Valley (fitting valley)
25 Valley part 31, 33, 133 Concave part 32, 134 Convex part

Claims (5)

A tension band,
A power transmission belt comprising a plurality of blocks arranged at a predetermined pitch along the longitudinal direction of the tension band and each having a fitting groove into which the tension band is fitted;
On the outer peripheral surface and inner peripheral surface of the tension band, one fitting mountain portion extending in the belt width direction is formed at the center in the belt longitudinal direction of the region facing the fitting groove of each block,
In at least the outer peripheral surface of the outer peripheral surface and inner peripheral surface of the tension band, the region facing the fitting groove of each block is located on both sides in the belt longitudinal direction of the fitting mountain portion , and the belt length Two fitting valleys having side surfaces on both sides in the direction and extending in the belt width direction are formed,
The power transmission belt according to claim 1, wherein the fitting groove has a concave portion and a convex portion that are fitted into the fitting mountain portion and the fitting valley portion, respectively.   2. The power transmission belt according to claim 1, wherein the tension band and each of the blocks are fixed by an adhesive at least at a fitting portion between the fitting mountain portion and the concave portion.   The inner peripheral surface of the tension band has only one valley between two adjacent fitting peaks, and the two fitting valleys in a region facing the fitting groove of each block. The power transmission belt according to claim 1, wherein the power transmission belt is not included. The inner peripheral surface of the tension band includes the fitting mountain portion and the two fitting valley portions in a region facing the fitting groove of each block. The power transmission belt described . The block has a configuration in which an upper beam and a lower beam arranged side by side in a belt thickness direction are connected by a pillar,
The power transmission belt according to claim 1, wherein the fitting grooves are formed on both sides of the pillar in the belt width direction.

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