JP2018123926A - Transmission belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress degradation of transmission efficiency, in a transmission belt having a plurality of elements, a lamination ring, and a retainer ring.SOLUTION: A transmission belt has a lamination ring, a plurality of elements, and a retainer ring, and is wound on a primary pulley and a secondary pulley. The element has a saddle face, a pair of pillar portions and a pair of hook portions. The retainer ring is positioned between an outer peripheral face of an outermost layer ring material of the lamination ring and an inner peripheral face of the hook portion. An outer peripheral length of the retainer ring is determined to be longer than 2×π×(r+t), when a circumferential rate is π, an inner diameter radius of an innermost layer ring material is r, and a radial height from the saddle face to the inner peripheral face of the hook portion is t.SELECTED DRAWING: Figure 5

Description

  The present specification discloses a transmission belt wound around a primary pulley and a secondary pulley of a continuously variable transmission.

  Conventionally, as this type of transmission belt, a belt that is stretched between a primary pulley and a secondary pulley of a continuously variable transmission and transmits the rotation of the primary pulley to the secondary pulley is known. For example, Patent Document 1 discloses an element having an endless metal band (laminated ring) and a plurality of metal elements that are stacked in the extending direction of the band. Each element has a pair of pillar portions extending upward from the upper ends on both sides of the body portion forming a horizontal portion, and a recess for accommodating a band is formed between the pair of pillar portions. Yes. Moreover, the front-end | tip of each pillar part is made into the engagement protrusion bent inside, and the open part slightly wider than a band is formed between a pair of engagement protrusion. In addition, after the band is accommodated in the recess of each element, a metal fall-off prevention body (retainer ring) that is slightly wider than between the pair of engagement protrusions is fitted through the opening, and the band falls off from the recess. Is prevented.

JP 2001-193996 A

  The transmission belt has a winding portion around which both pulleys are wound, and a linear chord portion that is not wound around both pulleys. In the winding portion, each element is caused by a frictional force generated in a tangential direction to the pulley. Torque is transmitted by pushing out the element in front of the belt travel direction. In such a transmission belt, between adjacent elements on one side of each chord part (the side from the smaller diameter pulley with the smaller winding diameter toward the larger diameter pulley with the larger winding diameter). There is a gap in If the element enters the winding part of the pulley (large diameter pulley) with a gap between adjacent elements, the load acting on the element due to the frictional force in the tangential direction with the pulley It is used for gap filling and torque transmission efficiency is reduced.

  The main object of the present disclosure is to suppress a decrease in transmission efficiency of a transmission belt having a plurality of elements, a laminated ring, and a retainer ring.

  The invention of the present disclosure has taken the following means in order to achieve the main object described above.

  The transmission belt of the present disclosure is a transmission belt that is wound around a primary pulley and a secondary pulley of a continuously variable transmission, and is formed in a ring shape in which a plurality of ring materials are stacked in a radial direction, and is supported by the stacking ring in an annular shape. A plurality of elements arranged, each element being in contact with the inner peripheral surface of the innermost layer ring material of the laminated ring, and from the both sides in the width direction of the saddle surface on the outer side in the radial direction of the laminated ring A pair of pillar portions extended to the pillar portion, a pair of hook portions projecting in the width direction of the saddle surface so as to face each other from an extension end of the pillar portion, and the stacking layer than the inner peripheral surface of the hook portion A plurality of elements having a rocking edge portion that is formed on the inner side in the radial direction of the ring and that is adjacent to each other and serves as a fulcrum of rotation of the two, A retainer ring disposed between an outer peripheral surface of the outermost layer ring material of the layer ring and an inner peripheral surface of the hook portion, and the outer peripheral length of the retainer ring is a circumferential ratio of π, and the innermost layer It is determined to be longer than 2 × π × (r + t), where r is the inner radius of the ring material and t is the radial height from the saddle surface to the inner peripheral surface of the hook portion. This is the gist.

  In this transmission belt according to the present disclosure, since the outer peripheral length of the retainer ring is determined to be longer than 2 × π × (r + t), the outer periphery of the retainer ring is in an unloaded state where the continuously variable transmission is not operating. The surface and the inner peripheral surface of the hook portion come into contact with each other. Further, even when tension is applied to the laminated ring during the operation of the continuously variable transmission and the laminated ring is stretched, the state in which the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion are in contact with each other is maintained. The In such a transmission belt, the retainer ring and the element circulate integrally at the winding portion of the large-diameter pulley. Since the retainer ring is located outside the locking edge portion in the radial direction of the ring, the circumferential speed of the retainer ring is higher than that of the locking edge portion at the winding portion of the large-diameter pulley. Exit to the string with the occurrence of. When the element and the retainer ring circulate around the small-diameter pulley and come out from the winding portion of the small-diameter pulley to the string portion, a speed difference is generated between the retainer ring and the locking edge portion. The retainer ring in contact with the inner peripheral surface of the hook portion accelerates the element in the belt traveling direction, and closes a gap between adjacent elements. As a result, the gap between adjacent elements is clogged before the element enters the winding portion of the large-diameter pulley, so that a reduction in torque transmission efficiency can be suppressed.

  Further, another transmission belt of the present disclosure is a transmission belt wound around a primary pulley and a secondary pulley of a continuously variable transmission, and a laminated ring in which a plurality of ring materials are laminated in a radial direction, and is supported by the laminated ring A plurality of elements arranged in an annular shape, each element including a saddle surface that contacts the inner peripheral surface of the innermost layer ring material of the laminated ring, and the laminated ring from both sides in the width direction of the saddle surface. A pair of pillar portions extending outward in the radial direction, a pair of hook portions projecting in the width direction of the saddle surface so as to face each other from the extending end of the pillar portion, and an inner peripheral surface of the hook portion A plurality of elements having a rocking edge portion that is formed on the inner side in the radial direction of the laminated ring and in which adjacent elements are in contact with each other and serve as a fulcrum for their rotation. And a retainer ring disposed between an outer peripheral surface of the outermost ring material of the laminated ring and an inner peripheral surface of the hook portion, and the outer peripheral length of the retainer ring is operated by the continuously variable transmission. In an unloaded state, the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion come into contact with each other, and the tensile force acting on the laminated ring during operation of the continuously variable transmission extends to the laminated ring. The gist of the present invention is that the contact between the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion is maintained even if the above occurs.

  In the other transmission belt of the present disclosure, the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion come into contact with each other in a no-load state where the continuously variable transmission is not operating. Further, even when tension is applied to the laminated ring during the operation of the continuously variable transmission and the laminated ring is stretched, the state in which the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion are in contact with each other is maintained. The In such a transmission belt, the retainer ring and the element circulate integrally at the winding portion of the large-diameter pulley. Since the retainer ring is located outside the locking edge portion in the radial direction of the ring, the circumferential speed of the retainer ring is higher than that of the locking edge portion at the winding portion of the large-diameter pulley. Exit to the string with the occurrence of. When the element and the retainer ring circulate around the small-diameter pulley and come out from the winding portion of the small-diameter pulley to the string portion, a speed difference is generated between the retainer ring and the locking edge portion. The retainer ring in contact with the inner peripheral surface of the hook portion accelerates the element in the belt traveling direction, and closes a gap between adjacent elements. As a result, the gap between adjacent elements is clogged before the element enters the winding portion of the large-diameter pulley, so that a reduction in torque transmission efficiency can be suppressed.

It is a lineblock diagram showing continuously variable transmission 1 which has transmission belt 10 of this indication. It is a fragmentary sectional view showing transmission belt 10 of this indication. 3 is a front view showing an element 20. FIG. FIG. 6 is a plan view showing a retainer ring 15. It is explanatory drawing which shows operation | movement of the transmission belt 10B of a comparative example, and operation | movement of the transmission belt 10 of this indication. It is explanatory drawing which shows operation | movement of the transmission belt 10B of a comparative example, and operation | movement of the transmission belt 10 of this indication. It is explanatory drawing which shows the clearance between the retainer ring 15 and the hook part 22f.

  Next, embodiments for carrying out the invention of the present disclosure will be described with reference to the drawings.

  FIG. 1 is a configuration diagram illustrating a continuously variable transmission 1 having a transmission belt 10 of the present disclosure. As shown in the figure, the continuously variable transmission 1 includes a primary shaft 2 as a drive side rotation shaft, a primary pulley 3 that rotates integrally with the primary shaft 2, and a driven side rotation shaft that is arranged in parallel with the primary shaft 2. Secondary shaft 4, a secondary pulley 5 that rotates integrally with the secondary shaft 4, a transmission belt wound around a pulley groove (V-shaped groove) of the primary pulley 3 and a pulley groove (V-shaped groove) of the secondary pulley 5. 10 and. The primary shaft 2 is connected to an input shaft connected to a power source such as an engine via a forward / reverse switching mechanism. The secondary shaft 4 is connected to the drive shaft via a gear mechanism or a differential gear. The continuously variable transmission 1 can change the torque transmitted to the primary shaft 2 steplessly and output it to the secondary shaft 4 by changing the groove width of the primary pulley 3 and the groove width of the secondary pulley 5. .

  FIG. 2 is a partial cross-sectional view showing the transmission belt 10. As shown in the figure, the transmission belt 10 includes a single laminated ring 12 formed by laminating a plurality of (in this embodiment, nine) ring members 11 in the ring radial direction (thickness direction), and a laminated ring 12. A plurality of (for example, several hundreds) elements 20 and one retainer ring 15 arranged in a ring shape (bundled) along the inner peripheral surface of each of them.

  The plurality of ring members 11 constituting the laminated ring 12 are each elastically deformable cut out from a steel plate drum, and are processed to have substantially the same thickness and different perimeters predetermined for each. Has been.

  Each element 20 is punched from a steel plate by, for example, press working, and as shown in FIG. 2, the body portion 21 extends horizontally in the drawing, and extends in the same direction from both end portions of the body portion 21. It has a pair of pillar part 22 and the recessed part 23 as a ring accommodating part defined between a pair of pillar part 22 so that it might open to the extension side of each pillar part 22. As shown in FIG. The pair of pillar portions 22 are arranged in the radial direction of the laminated ring 12 from both sides in the width direction of the saddle surface 23 s which is the bottom surface of the recessed portion 23 (in the direction from the inner circumferential side to the outer circumferential side of the laminated ring 12, that is, upper in FIG. 2). A pair of hook portions 22f projecting in the width direction of the saddle surface 23s is formed at the extending end portion of each pillar portion 22. The pair of hook portions 22f protrude so as to be opposed to each other with an interval slightly longer than the width of the laminated ring 12 (ring material 11). As shown in FIG. 2, the laminated ring 12 is disposed in the concave portion 23, and the saddle surface 23s of the concave portion 23 is in contact with the inner peripheral surface of the laminated ring 12, that is, the inner peripheral surface of the innermost ring material 11i. ing. Note that the saddle surface 23s has a so-called crowning shape in which the central portion in the width direction is a top portion T and is gradually inclined downward in the figure as it goes outward in the width direction.

  In addition, as shown in FIG. 2, the element 20 has a substantially constant thickness on the pillar portion 22 side, that is, on the outer side in the radial direction of the laminated ring 12, and when the element 20 is viewed in plan, It is formed so that the thickness gradually decreases from the straight line L0 (the plane contacting the saddle surface 23s at the top T) extending in the width direction of the saddle surface 23s to the side opposite to the pillar portion 22, that is, inward in the radial direction of the laminated ring 12. Has been. And the boundary part where the thickness of the element 20 changes makes the rocking edge 25 used as the fulcrum of both rotation by making the elements 20 adjacent in the advancing direction of the power transmission belt 10 contact. That is, the locking edge 25 is located on a straight line L0 that extends in the width direction of the saddle surface 23s through the top portion T (included in a plane that contacts the saddle surface 23s at the top portion T).

  One projection (dimple) 26 is formed at the center in the width direction of the front surface (one surface) of the body portion 21 of the element 20. A depression 27 into which the protrusion 26 is loosely fitted is formed. The element 20 has a pair of side surfaces 20f that are formed so as to be separated from each other toward the outer peripheral side (the outer side in the radial direction of the transmission belt 10) from the inner peripheral side of the transmission belt 10 and function as flank surfaces.

  The retainer ring 15 is an elastically deformable material cut out from, for example, a steel plate drum, and has a thickness that is substantially the same as or thinner than the ring material 11 and a width that is longer than the distance between the pair of hook portions 22f. Is formed. The retainer ring 15 is elastically deformed in the width direction with the laminated ring 12 accommodated in the recesses 23 of all the elements 20 and is fitted into the recesses 23 between the pair of hook portions 22 f of each element 20. It is. Accordingly, the retainer ring 15 is disposed between the outer peripheral surface of the ring material 11o of the outermost layer of the multilayer ring 12 and the inner peripheral surface of the hook portion 22f of each element 20, and surrounds the multilayer ring 12, and each element 20 Is prevented from falling off the laminated ring 12. In this embodiment, the retainer ring 15 is formed with an opening (elongate hole) 15o as shown in FIG. 3, which makes it easy to elastically deform the retainer ring 15 in the width direction, and sets the element 20 Adequacy can be secured.

  Such a transmission belt 10 includes winding portions M1 and M2 wound around the primary pulley 3 and the secondary pulley 5, and linear string portions N1 and N2 which are not wound around the pulley, and the winding portions M1 and M2 While the element 20 receives the clamping pressure from the pulley at the pair of side surfaces (flank surfaces) 20f, torque is transmitted by pushing the element 20 forward in the belt traveling direction by the frictional force in the tangential direction with the pulley. Of both pulleys, the pulley on the side from the larger diameter pulley (primary pulley 3 in the example of FIG. 1) to the smaller diameter pulley (secondary pulley 5 in the example of FIG. 1) having the smaller winding diameter. As shown in FIG. 1, the string portion N1 is a compression-side string portion in which no gap is generated between adjacent elements 20 in accordance with the operation of the continuously variable transmission 1, and the side toward the large-diameter side pulley from the small-diameter side pulley. As shown in FIG. 1, the chord portion N2 is a slack-side chord portion in which a gap is formed between the adjacent elements 20 with the operation of the continuously variable transmission 1. When the element 20 enters the winding portion M1 of the large-diameter pulley with a gap formed between adjacent elements 20 in the slack-side string portion N2, the transmission belt of the comparative example of FIG. As shown in FIG. 10B, the load acting on the element 20B due to the frictional force in the tangential direction with the large-diameter pulley is used to close the gap between the front element 20 in the belt traveling direction and the torque transmission efficiency decreases. .

  Here, in the transmission belt 10 including the retainer ring 15, if the outer peripheral surface of the retainer ring 15 and the inner peripheral surface of the hook portion 22 f of the element are in contact with each other during the operation of the continuously variable transmission 1, The retainer ring 15 and the element 20 circulate integrally in the winding portion M1 of the radial pulley. In this case, the retainer ring 15 on the outer side in the radial direction has a higher peripheral speed than the locking edge portion 25 on the inner side in the radial direction. Therefore, the retainer ring 15 is wound at a higher speed than the locking edge portion 25. Exit from M1 to string N1. Then, as shown in FIG. 5 (b), when the retainer ring 15 and the element 20 circulate around the winding portion M2 of the small-diameter pulley while maintaining the speed difference, the retainer ring 15 is pulled out to the string portion N2. The element 20 in contact with the inner peripheral surface of the hook portion 22f is accelerated in the belt traveling direction, and the gap between the adjacent elements 20 is reduced. As a result, the element 20 enters the winding portion M1 of the large-diameter pulley in a state where the gap between the adjacent elements 20 is closed, so that the above-described reduction in torque transmission efficiency can be suppressed.

  As shown in the transmission belt 10B of the comparative example in FIG. 6A, when a clearance is formed between the outer peripheral surface of the retainer ring 15B and the inner peripheral surface of the hook portion of the element 20B, the element 20B While the element 20B swings (pitches) when the winding part M2 exits, its behavior deteriorates, whereas the outer peripheral surface of the retainer ring 15 and the inner peripheral surface of the hook portion 22f of the element 20 come into contact with each other. 6B, the element 20 is supported by the retainer ring 15, so that the behavior of the element 20 can be stabilized.

  In view of the above, in the present embodiment, the outer peripheral length of the retainer ring 15 is as shown in FIG. 2 when the continuously variable transmission 1 is not in operation (no tension is applied to the laminated ring 12). As shown, the outer peripheral surface of the retainer ring 15 is in contact with the inner peripheral surface of the hook portion 22 f of each element 20, and a compressive stress is applied to the retainer ring 15. That is, the circumference ratio is π, the inner diameter radius of the innermost ring material 11i of the laminated ring 12 is r (mm), and the radial height from the saddle surface 23s of each element 20 to the inner peripheral surface of the hook portion 22f is high. When the thickness is t (mm), the outer peripheral length L of the retainer ring 15 is determined so as to satisfy the following expression (1). Thereby, the retainer ring 15 is assembled so as to be press-fitted into the inner peripheral surface of the hook portion 22 f of each element 20. In this case, a clearance is formed between the inner peripheral surface of the retainer ring 15 and the outer peripheral surface of the outermost ring material 11 o of the laminated ring 12.

  L> 2 × π × (r + t) (1)

  When the laminated ring 12 is stretched due to the tension acting on the laminated ring 12 during the operation of the continuously variable transmission 1, the element 20 moves in the radial direction as the laminated ring 12, that is, the innermost ring material 11i expands. Inflates outward. The retainer ring 15 is assembled so that the outer peripheral surface thereof is press-fitted into the inner peripheral surface of the hook portion 22f of each element 20, and a compressive stress is applied. Therefore, even if the element 20 swells, the hook portion 22f The state which contact | abutted with the internal peripheral surface of is maintained. Thereby, in the slack side string portion N2, before the element 20 enters the winding portion M1, the gap between the adjacent elements 20 can be reduced by the speed difference between the retainer ring 15 and the locking edge portion 25. This can suppress the above-described reduction in torque transmission efficiency.

  FIG. 7 is an explanatory view showing the clearance between the retainer ring 15 and the hook portion 22 f of the element 20. In the continuously variable transmission 1, the greater the torque transmitted to the primary pulley 3, the greater the tension acting on the laminated ring 12. As shown in FIG. 7, the amount of elongation (distance from the center) of the laminated ring 12 increases. Since it becomes large, the amount of swelling of the element 20 (hook part 22f) becomes large. Here, A in the drawing is a stacking when the compression (press-fit) of the retainer ring 15 is released and the outer peripheral surface of the retainer ring 15 and the inner peripheral surface of the hook portion 22f of the element 20 begin to separate in this embodiment. The tension acting on the ring 12 is shown. Further, B in the figure shows the tension acting on the laminated ring 12 when the torque transmitted to the primary pulley 3 becomes maximum when the continuously variable transmission 1 is in the minimum reduction ratio state, and C in the figure shows the continuously variable transmission. The tension acting on the laminated ring 12 when the torque transmitted to the primary pulley 3 becomes maximum when the machine 1 is in the maximum reduction ratio state is shown. When the stress acting on the laminated ring 12 due to the tension exceeds the absolute value of the compressive stress acting on the retainer ring 15 in the unloaded state, the retainer ring 15 is released from compression (press-fit), and the hook portion 22f of the element 20 is released. It is spaced apart from the inner peripheral surface. In this embodiment, when the Young's modulus of the retainer ring 15 is E (Mpa), the outer peripheral length L of the retainer ring 15 can be determined so as to satisfy the following expression (2). In this case, the outer peripheral length L of the retainer ring 15 is the absolute value of the compressive stress (residual compressive stress) that acts on the retainer ring 15 in the above-described no-load state when being pressed into the inner peripheral surface of the hook portion 22f of each element 20. It can be said that is determined to be larger than 0 Mpa and smaller than 130 Mpa. The retainer ring 15 releases the compression (press-fit) when the stress acting on the laminated ring 12 due to tension exceeds the residual compressive stress in the unloaded state, and the inner peripheral surface of the hook portion 22f of the element 20 Will be separated. This is because, if the outer peripheral length of the retainer ring 15 is too short, it immediately separates from the inner peripheral surface of the hook portion 22f of the element 20 when the laminated ring 12 is stretched by the tension acting on the laminated ring 12. Thus, the effect of suppressing the reduction in torque transmission efficiency cannot be obtained sufficiently, and if the outer peripheral length of the retainer ring 15 is too long, the compressive stress acting on the retainer ring 15 becomes excessive, and the transmission ring 10 is warped. It is.

  0 <L <2 × π × (r + t) + 130 / E (2)

  In the embodiment described above, the outer peripheral length of the retainer ring 15 is determined so as to satisfy the expression (2). However, the torque transmitted to the primary pulley 3 is maximum when the continuously variable transmission 1 is at the minimum reduction ratio. Then, it is determined so that the contact between the outer peripheral surface of the retainer ring 15 and the inner peripheral surface of the hook portion 22f is maintained up to the extension amount (B in FIG. 6) by which the laminated ring 12 extends by the action of tension. It may be a thing.

  As described above, the transmission belt according to the present disclosure includes a plurality of rings in the radial direction in the transmission belt (10) wound around the primary pulley (3) and the secondary pulley (5) of the continuously variable transmission (1). A laminated ring (12) in which materials (11) are laminated, and a plurality of elements (20) supported by the laminated ring (12) and arranged in an annular shape, each element (20) being the laminated ring The saddle surface (23s) in contact with the inner peripheral surface of the innermost ring material (11i) of (12) and the outer side in the radial direction of the laminated ring (12) from both sides in the width direction of the saddle surface (23s) A pair of pillar portions (22) that are extended, a pair of hook portions (22f) that protrude in the width direction of the saddle surface (23s) so as to face each other from the extending ends of the pillar portions (22), and Huh A locking edge portion (25) which is formed on the inner side in the radial direction of the laminated ring (12) with respect to the inner peripheral surface of the portion (22f), and adjacent elements (20) come into contact with each other to serve as a fulcrum for their rotation. And a retainer ring (15) disposed between the outer peripheral surface of the outermost ring material (11o) of the laminated ring (12) and the inner peripheral surface of the hook portion (22f). The outer peripheral length of the retainer ring (15) is such that the circumference ratio is π, the inner radius of the innermost ring material (11i) is r, and the hook portion (22f) from the saddle surface (23s) ) Is defined to be longer than 2 × π × (r + t) where t is the radial height to the inner peripheral surface.

  In this transmission belt according to the present disclosure, since the outer peripheral length of the retainer ring is determined to be longer than 2 × π × (r + t), the outer periphery of the retainer ring is in an unloaded state where the continuously variable transmission is not operating. The surface and the inner peripheral surface of the hook portion come into contact with each other. Further, even when tension is applied to the laminated ring during the operation of the continuously variable transmission and the laminated ring is stretched, the state in which the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion are in contact with each other is maintained. The In such a transmission belt, the retainer ring and the element circulate integrally at the winding portion of the large-diameter pulley. Since the retainer ring is located outside the locking edge portion in the radial direction of the ring, the circumferential speed of the retainer ring is higher than that of the locking edge portion at the winding portion of the large-diameter pulley. Exit to the string with the occurrence of. When the element and the retainer ring circulate around the small-diameter pulley and come out from the winding portion of the small-diameter pulley to the string portion, a speed difference is generated between the retainer ring and the locking edge portion. The retainer ring in contact with the inner peripheral surface of the hook portion accelerates the element in the belt traveling direction, and closes a gap between adjacent elements. As a result, the gap between adjacent elements is clogged before the element enters the winding portion of the large-diameter pulley, so that a reduction in torque transmission efficiency can be suppressed.

  In such a transmission belt, the outer peripheral length of the retainer ring (15) is determined to be shorter than 2 × π × (r + t) + 130 / E, where E is the Young's modulus of the retainer ring (15). It is good as it is. In this case, the absolute value of the compressive stress acting on the retainer ring in a state where the outer peripheral surface of the retainer ring is in contact with the inner peripheral surface of the hook portion is less than 130 Mpa. Thereby, when a retainer ring is assembled | attached to each element, it can suppress that a retainer ring warps. In other words, the outer peripheral length of the retainer ring can be prevented from becoming too long while covering the operating area of the continuously variable transmission that requires efficiency.

  In addition, another transmission belt of the present disclosure includes a plurality of ring members (in the radial direction) in the transmission belt (10) wound around the primary pulley (3) and the secondary pulley (5) of the continuously variable transmission (1). 11) and a plurality of elements (20) arranged in an annular shape supported by the laminated ring (12), each element (20) being arranged in the laminated ring (12). ) Of the innermost ring material (11i) and the saddle surface (23s) in contact with the inner peripheral surface of the inner ring material (11i), and the outer side in the radial direction of the laminated ring (12) from both sides of the saddle surface (23s) in the width direction. A pair of pillar portions (22), a pair of hook portions (22f) projecting in the width direction of the saddle surface (23s) so as to face each other from the extending ends of the pillar portions (22), and the hook portions (22 And a locking edge portion (25) which is formed on the inner side in the radial direction of the laminated ring (12) with respect to the inner peripheral surface of the laminated ring (12) and which is adjacent to each other (20) and serves as a fulcrum for their rotation. The retainer ring (15) disposed between the outer peripheral surface of the outermost ring material (11o) of the laminated ring (12) and the inner peripheral surface of the hook portion (22f). And the outer peripheral length of the retainer ring (15) is such that the outer peripheral surface of the retainer ring (15) and the hook portion (22f) are in an unloaded state when the continuously variable transmission (1) is not operating. Even if the laminated ring (12) is extended by the tension applied to the laminated ring (12) during operation of the continuously variable transmission (1), the retainer ring (15) is in contact with the peripheral surface. Outer surface and hook It is summarized as the contact between the inner circumferential surface of (22f) is defined so as to maintain.

  In the other transmission belt of the present disclosure, the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion come into contact with each other in a no-load state where the continuously variable transmission is not operating. Further, even when tension is applied to the laminated ring during the operation of the continuously variable transmission and the laminated ring is stretched, the state in which the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion are in contact with each other is maintained. The In such a transmission belt, the retainer ring and the element circulate integrally at the winding portion of the large-diameter pulley. Since the retainer ring is located outside the locking edge portion in the radial direction of the ring, the circumferential speed of the retainer ring is higher than that of the locking edge portion at the winding portion of the large-diameter pulley. Exit to the string with the occurrence of. When the element and the retainer ring circulate around the small-diameter pulley and come out from the winding portion of the small-diameter pulley to the string portion, a speed difference is generated between the retainer ring and the locking edge portion. The retainer ring in contact with the inner peripheral surface of the hook portion accelerates the element in the belt traveling direction, and closes a gap between adjacent elements. As a result, the gap between adjacent elements is clogged before the element enters the winding portion of the large-diameter pulley, so that a reduction in torque transmission efficiency can be suppressed.

  In the other transmission belt, the outer peripheral length of the retainer ring (15) is such that the torque input to the primary pulley (3) becomes maximum when the continuously variable transmission (1) is in the minimum reduction ratio. The contact between the outer peripheral surface of the retainer ring (15) and the inner peripheral surface of the hook portion (22f) is maintained up to the extension amount of the stacked ring (12) by the tension acting on the stacked ring (12). It is good also as what is prescribed in. In this way, it is possible to prevent the outer peripheral length of the retainer ring from becoming too long while covering an operating region where efficiency is required.

  Further, in another transmission belt, the outer peripheral length of the retainer ring (15) is such that the retainer ring (15) does not warp when the retainer ring (15) is assembled to the plurality of elements (20). It may be determined as follows. In this way, the behavior of the element can be stabilized.

  It goes without saying that the invention of the present disclosure is not limited to the embodiment described above, and various modifications can be made within the scope of the extension of the present disclosure. Furthermore, the above-described embodiment is merely a specific form of the invention described in the Summary of Invention column, and does not limit the elements of the invention described in the Summary of Invention column.

  The invention of the present disclosure can be used in the manufacturing industry of transmission belts and continuously variable transmissions.

  1 continuously variable transmission, 2 primary shaft, 3 primary pulley, 4 secondary shaft, 5 secondary pulley, 10 transmission belt, 11 ring material, 11i innermost layer ring material, 11o outermost layer ring material, 12 laminated ring, 15 retainer ring, 15o opening, 20 element, 20f side, 21 trunk, 22 pillar, 22f hook, 23 recess, 23s saddle surface, 25 locking edge, 26 projection, 27 depression, M1, M2 winding, N1, N2 string Department.

Claims (5)

In the transmission belt wound around the primary pulley and the secondary pulley of the continuously variable transmission,
A laminated ring in which a plurality of ring materials are laminated in the radial direction;
A plurality of elements that are supported by the stacked ring and arranged in an annular shape, each element being in contact with the inner peripheral surface of the innermost ring material of the stacked ring, and both sides in the width direction of the saddle surface A pair of pillar portions extending outward in the radial direction of the laminated ring, a pair of hook portions projecting in the width direction of the saddle surface so as to face each other from the extending end of the pillar portion, and the hook A plurality of elements having a rocking edge portion that is formed on the inner side in the radial direction of the laminated ring than the inner peripheral surface of the portion and that is adjacent to each other and serves as a fulcrum of rotation of both;
A retainer ring disposed between the outer peripheral surface of the outermost ring material of the laminated ring and the inner peripheral surface of the hook part,
The outer peripheral length of the retainer ring is defined as follows: pi is the circumference ratio, r is the inner radius of the innermost ring material, and t is the radial height from the saddle surface to the inner peripheral surface of the hook portion. It is determined to be longer than 2 × π × (r + t).
Transmission belt. The transmission belt according to claim 1, wherein
The outer peripheral length of the retainer ring is determined to be shorter than 2 × π × (r + t) + 130 / E, where E is the Young's modulus of the retainer ring.
Transmission belt. In the transmission belt wound around the primary pulley and the secondary pulley of the continuously variable transmission,
A laminated ring in which a plurality of ring materials are laminated in the radial direction;
A plurality of elements that are supported by the stacked ring and arranged in an annular shape, each element being in contact with the inner peripheral surface of the innermost ring material of the stacked ring, and both sides in the width direction of the saddle surface A pair of pillar portions extending outward in the radial direction of the laminated ring, a pair of hook portions projecting in the width direction of the saddle surface so as to face each other from the extending end of the pillar portion, and the hook A plurality of elements having a rocking edge portion that is formed on the inner side in the radial direction of the laminated ring than the inner peripheral surface of the portion and that is adjacent to each other and serves as a fulcrum of rotation of both;
A retainer ring disposed between the outer peripheral surface of the outermost ring material of the laminated ring and the inner peripheral surface of the hook part,
The outer peripheral length of the retainer ring is such that the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion are in contact with each other in an unloaded state where the continuously variable transmission is not operating, and the operation of the continuously variable transmission is It is determined that the contact between the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion is maintained even if the laminate ring is stretched by tension acting on the laminate ring.
Transmission belt. The transmission belt according to claim 3, wherein
The outer peripheral length of the retainer ring is the extent to which the laminated ring extends due to the tension acting on the laminated ring when the torque input to the primary pulley is maximized when the continuously variable transmission is at the minimum reduction ratio. It is determined that the contact between the outer peripheral surface of the retainer ring and the inner peripheral surface of the hook portion is maintained.
Transmission belt. The transmission belt according to claim 3 or 4,
The outer peripheral length of the retainer ring is determined so that the retainer ring does not warp when the retainer ring is assembled to the plurality of elements.
Transmission belt.

Images