JP2011169454A - Push type transmission belt - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a push type transmission belt capable of preventing sliding loss caused by clearance between elements and improving power transmission efficiency. <P>SOLUTION: The push type transmission belt B includes many elements 1 formed in a thin plate piece and rings 2 and 3 for binding the many elements 1 in a state annularly arranged by aligning attitude thereof, and transmits power between two pulleys by sequentially pressing the preceding element 1 by other element 1. The push transmission belt is constituted for thermally expanding the element 1 by heat generation accompanying the power transmission so that the increase of the clearance between mutually adjacent elements 1 due to expansion of circumferential lengths of the rings 2 and 3 is prevented when the power is transmitted. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a transmission belt configured by arranging a large number of plate-like elements in a ring shape and binding them in a ring shape by assembling them in a band-like ring, and in particular, each element sequentially presses the preceding element. Thus, the present invention relates to a pressure transmission belt that transmits torque between two pulleys.

  As a power transmission belt used for a belt type continuously variable transmission or the like, a pressure type transmission belt is known. In general, this type of transmission belt is called a ring or a band, in which a large number of plate-like pieces (hereinafter referred to as elements) called elements or blocks are aligned with each other in the same posture and arranged in an annular shape. It is comprised by bundling in cyclic | annular form with the cyclic | annular body (henceforth a ring). The left and right side surfaces of the element are so-called flank surfaces formed in a V shape corresponding to the V groove of the pulley, and the flank surface contacts the surface of the V groove of the pulley, and torque is generated at the contact portion. Is configured to communicate.

  When the transmission belt configured as described above is sandwiched between pulleys, a force is exerted on the element to push it outward. Therefore, tension acts on the ring that binds the elements. In this state, when torque is applied to the driving pulley and the driving pulley rotates, the element sandwiched between the driving pulley rotates together with the driving pulley. At this time, since the transmission belt is stretched between the driving pulley and the driven pulley, the element is pushed out of the driving pulley at the so-called linear portion between the pulleys, and the preceding other pulleys. Press the element. The elements that are sequentially pressed in this way enter the V groove in the driven pulley and are sandwiched in the V groove, and rotate together with the driven pulley. That is, the driven pulley is rotated by the elements that are sequentially pressed from the other elements behind and enter the V-groove. In this way, torque is transmitted from the driving pulley to the driven pulley.

  An example of such a pressure transmission belt is described in Patent Document 1. The continuously variable transmission belt described in Patent Document 1 is formed in a plate shape and arranged in an annular shape so as to face each other, and adjacent to each other in a state in which a large number of these elements are arranged in a circular arc shape. A plurality of elements formed with a locking edge that contacts other elements, and a ring that is wound around the saddle surface of the element so that the inner peripheral surface is in contact with each other, and binds the multiple elements in an annular shape Yes. The belt for continuously variable transmission described in Patent Document 1 is a distance between the locking edge of the element and the saddle surface in order to correct the posture of the element with respect to the pulley and prevent uneven wear of the element and the pulley. However, it is configured such that one of the left and right sides in the belt width direction is relatively short and the other is relatively long.

  In Patent Document 2, in the transmission belt of a belt-type continuously variable transmission, air is blown so as to close a gap in the stacking direction between elements that are not in contact with the pulleys, so that the contact portion between the elements and the pulleys is reduced. It is described that slip transmission is reduced to improve power transmission efficiency.

JP 2008-240958 A JP 2008-128304 A

  The press-type transmission belt used in the belt-type continuously variable transmission as described in Patent Documents 1 and 2 above is configured by binding a large number of elements with a ring as described above. It itself is a discontinuous so-called discrete body. Moreover, in order to ensure the softness | flexibility, flexibility, or assembly property as a transmission belt, the clearance gap inevitably exists between the mutually adjacent elements. On the other hand, a ring in which a large number of elements are bundled in an annular shape is tensioned as described above when it is wound around a pulley and travels as a transmission belt. Elastically deforms in the direction of expansion. Therefore, when the transmission belt runs, the gap between adjacent elements of a large number of elements bound by the ring increases.

  As described above, the transmission belt in this case is a pressing type transmission belt that transmits power between two pulleys by using a pressing force generated between a large number of elements. When the gap between adjacent elements increases during the running of the belt, slip occurs between the element and the ring when the gap between the elements is reduced by the pressing force during power transmission. Therefore, the slip is a loss, and the power transmission efficiency of the transmission belt is reduced accordingly. As described above, there is still room for improvement in the push-type transmission belt in order to improve the power transmission efficiency.

  This invention was made paying attention to said technical subject, and it aims at providing the press-type transmission belt which can suppress the slip loss resulting from the clearance gap between elements, and can improve power transmission efficiency. It is what.

  In order to achieve the above object, the invention of claim 1 includes a large number of elements formed in a plate shape, and a ring that binds the large number of elements in a state in which the postures are aligned in an annular shape, In a pressure type transmission belt that transmits power between two pulleys by sequentially pressing the other elements preceded by the element, when the power is transmitted, the circumference of the ring is expanded and adjacent to each other. The pressure transmission belt is characterized in that the element is thermally expanded by heat generated by the power transmission so as to suppress an increase in the gap between the elements.

  The invention of claim 2 is the invention of claim 1, wherein the element has a relatively small linear expansion coefficient and a main material forming a main part of the element, and a thermal expansion having a relatively large linear expansion coefficient. It is a press type transmission belt characterized by being formed of a plurality of materials having different linear expansion coefficients from the material.

  According to a third aspect of the present invention, in the invention of the second aspect, at least one surface of the element facing other elements adjacent to each other before and after the element is formed of the thermal expansion material. Is a pressure transmission belt characterized by

  According to the first aspect of the present invention, during a load operation in which the transmission belt transmits power, the ring that binds a number of elements expands in the direction of tension, and the gap between adjacent elements increases. In this case, according to the first aspect of the present invention, since the elements are thermally expanded due to the heat generated when the transmission belt is loaded, the increase in the gap between the adjacent elements as described above is suppressed. be able to. Therefore, it is possible to avoid or suppress an increase in the gap between adjacent elements during load operation of the transmission belt, and an increase in loss due to slip generated between the element and the ring. As a result, the power transmission efficiency of the transmission belt can be improved.

  According to the invention of claim 2, the main part of the element has a small linear expansion coefficient, and is formed of a high-strength main material such as steel. And the other site | part of an element is formed from a thermal expansion material with a large linear expansion coefficient. Therefore, a portion having a large linear expansion coefficient can be formed using the thermal expansion material while ensuring the strength and durability of the main part of the element using the main material.

  According to the invention of claim 3, at least one of the front and rear surfaces of the element, that is, the surface that faces and abuts other adjacent elements, is formed of the thermal expansion material having a large linear expansion coefficient. Therefore, even when the gap between the elements increases during the load operation of the transmission belt, the gap between the elements can be reliably reduced by the thermal expansion of the portion formed of the thermal expansion material. it can.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the structural example of the press-type power transmission belt which concerns on this invention, Comprising: (a) is a front view which shows the structure of an element, and sectional drawing which shows the structure of a ring, (b) is the principal part of an element especially It is a side view (partial sectional view) showing the configuration of the thermal expansion part.

  Next, the present invention will be specifically described with reference to the drawings. FIG. 1 shows a part of a pressure transmission belt B according to the present invention. This belt B has a large number of elements 1 arranged in an annular shape with their respective postures aligned. 3 is formed by bundling. For example, as shown in FIG. 1, the element 1 is a metal plate-like member, and the left and right side surfaces 4 and 5 in the width direction (left and right direction in FIG. 1A) are elements. 1 has a plate portion 6 which is a base (main body) portion formed as a so-called V-shaped inclined surface when viewed from the front, and the inclined left and right side surfaces 4 and 5 are involved in power transmission. It is a surface.

  A neck portion 7 extending upward in FIG. 1, in other words, extending from the plate portion 6 in the thickness direction of the belt B is formed at the center portion in the width direction of the plate portion 6. A head portion 8 extending in an umbrella shape on both sides of the plate portion 6 in the width direction is formed integrally with the neck portion 7 at the upper end portion of the neck portion 7. Accordingly, a slit portion (groove portion) opened in the left-right direction in FIG. 1A between the upper edge portion in FIG. 1 of the plate portion 6 and the lower edge portion in FIG. 1 of the head portion 8. 9, 10 are formed. The slit portions 9 and 10 are portions for inserting and winding the rings 2 and 3 for annularly binding the elements 1 arranged in an annular shape in close contact with each other. The upper edge portions of the ring 2 are saddle surfaces 11 and 12 on which the inner peripheral surfaces of the rings 2 and 3 are placed in contact.

  Since the elements 1 are arranged in an annular shape in a state of being in close contact with each other and are bound by the rings 2 and 3, in order to maintain a close contact state and smoothly bend at the portion of the belt B that is curved as a whole. In addition, the lower portion of each element 1 in FIG. 1 (the portion closer to the center in the annular arrangement) is thinned. That is, one side of the plate portion 6 (for example, the left side surface in FIG. 1B) is lower than the saddle surfaces 11 and 12 by a predetermined dimension (offset) from the lower side (in FIG. 1B). The lower part is thinned and is thinned. Therefore, when each element 1 expands in a fan shape and comes into contact, in other words, when each element 1 is curved and arranged in an arc shape and curves as the belt B, it contacts at the boundary portion where the plate thickness changes. The edge of this boundary part is a rocking edge 13.

  The head 8 of each element 1 is formed with a convex portion (boss) 14 and a concave portion (hole) 15 on the opposite side for determining the relative positions of the adjacent elements 1. That is, the boss 14 is formed at the extended position of the neck portion 7 (or the central portion of the head portion 8), and the hole 15 is formed on the surface opposite to the boss 14.

  The rings 2 and 3 are formed by laminating a plurality of thin metal strips. Then, one ring 2 is inserted into one slit portion 9 in a large number of elements 1 arranged in an annular shape in the same direction, and the other ring 3 is inserted into the other slit portion 10. , 3 are in contact with the saddle surfaces 11, 12.

  As described above, the transmission belt B in the present invention is a pressing belt that transmits power between two pulleys by using the pressing force generated between a large number of elements. Therefore, when the transmission belt B is wound around two pulleys and power is transmitted between the pulleys, tension is applied to the rings 2 and 3, and the tension causes the rings 2 and 3 to act on the tension in the direction of action. That is, the circumference of the rings 2 and 3 is expanded. When the circumferential length of the rings 2 and 3 is increased, the gaps between the elements 1 adjacent to each other of the multiple elements 1 bound by the rings 2 and 3 are increased. When the gap between the adjacent elements 1 increases, the slip generated between each element 1 and the rings 2 and 3 increases. Therefore, the transmission belt B in the present invention is such that even when the gap between the adjacent elements 1 increases during load operation in which power is transmitted between the two pulleys, the element 1 is thermally expanded and the gap It is configured to suppress the increase. In other words, this transmission belt B is subjected to heat generated by power transmission so as to suppress an increase in the gap between adjacent elements 1 due to expansion of the circumferential length of the rings 2 and 3 when power transmission is performed. Each element 1 is configured to thermally expand.

  Specifically, each element 1 in the transmission belt B includes a main portion 16 formed of a main material having a relatively large linear expansion coefficient and a heat formed of a heat expansion material having a relatively small linear expansion coefficient. It is comprised from the expansion part 17. FIG. In other words, each element 1 in the transmission belt B includes a main material forming the main portion 16 of the element 1 with a relatively small linear expansion coefficient, and a thermal expansion portion 17 of the element 1 with a relatively large linear expansion coefficient. It is formed of a plurality of materials having different linear expansion coefficients from the constituent thermal expansion material. In particular, at least one of the surfaces facing the other elements 1 adjacent to each other before and after the predetermined element 1 is formed of a thermal expansion material. That is, at least one of the surfaces serves as the thermal expansion portion 17. In the configuration example shown in FIG. 1B, the rear surface 1r on the side where the holes 15 of the element 1 are formed (the right side in FIG. 1B) has a thermal expansion portion 17 formed of a thermal expansion material. It has become.

  The main part 16 is a part constituting the main part of the element 1 as the name suggests. The left and right side surfaces 4 and 5 of the element 1, the plate part 6, the neck part 7, the head part 8, the slit parts 9 and 10, and the saddle. Surfaces 11 and 12, a locking edge 13, a boss 14 and a hole 15 are formed. The main material forming the main portion 16 is a material having a relatively low linear expansion coefficient such as carbon tool steel or alloy tool steel and having a predetermined strength required for the element 1.

  On the other hand, the thermal expansion portion 17 is a portion constituting the rear surface 1r of the element 1, and may form a part of the main portion of the element 1 mentioned above. 1B shows an example in which the thermal expansion portion 17 is formed on the rear surface 1r of the element 1, the thermal expansion portion 17 in the present invention is, for example, the front surface of the element 1 (see FIG. 1 (B) on the left side surface 1f. Or the structure by which the thermal expansion part 17 was formed in both the front surface 1f and the rear surface 1r with respect to the main part 16 which forms the center part of the plate | board thickness direction (left-right direction in FIG. 1 (B)) of the element 1 It may be. The thermal expansion material forming the thermal expansion portion 17 has a coefficient of linear expansion larger than that of the main material, such as an aluminum alloy, a copper alloy, or a synthetic resin. Is used.

  In this way, the element 1 has a mutual line between the main material having a relatively small linear expansion coefficient and a predetermined strength required for the element 1, and the thermal expansion material having a larger linear expansion coefficient than the main material. Since it is formed of two types of materials having different expansion coefficients, the main portion 16 formed of the main material secures the required strength of the element 1 and is formed of a heat expansion material as the temperature rises during load operation. The thermal expansion portion 17 can be greatly expanded.

  According to the invention of claim 2, the main part of the element has a small linear expansion coefficient, and is formed of a high-strength main material such as steel. And the other site | part of an element is formed from a thermal expansion material with a large linear expansion coefficient. Therefore, a portion having a large linear expansion coefficient can be formed using the thermal expansion material while ensuring the strength and durability of the main part of the element using the main material.

  As described above, according to the transmission belt B of the present invention, the elements are arranged so as to close the gap between the elements 1 that increase during the load operation of the transmission belt B due to heat generated by the load operation of the transmission belt B. 1 thermally expands. That is, the front and rear surfaces 1f and 1r of the element 1, that is, at least one of the surfaces 1r (or 1f or 1f or 1r) that abuts against the other adjacent elements 1 is a thermal expansion material having a large linear expansion coefficient. Formed by. For this reason, even when the gap between the elements 1 increases during the load operation of the transmission belt B, the thermal expansion portion 16 of the element 1 formed of the thermal expansion material expands particularly greatly, so that the element 1 The gap between them can be reliably reduced. Therefore, during the load operation of the transmission belt B, it is possible to avoid or suppress the increase in the gap between the adjacent elements and the increase in loss due to the slip generated between the element and the ring. Therefore, the power transmission efficiency of the transmission belt B can be improved correspondingly.

  The present invention is not limited to the specific examples described above. For example, in the specific example described above, the configuration in which the pressing transmission belt according to the present invention is applied to a belt type continuously variable transmission is described as an example. However, the pressing transmission belt according to the present invention is a belt type. The present invention is not limited to a continuously variable transmission, and can be applied as a pressure transmission belt for power transmission in another winding transmission device (belt transmission device) constituted by a belt and a pulley.

  DESCRIPTION OF SYMBOLS 1 ... Element, 1f ... Front surface, 1r ... Rear surface, 2, 3 ... Ring, 16 ... Main part, 17 ... Thermal expansion part, B ... Press-type transmission belt.

Claims (3)

  A plurality of elements formed in a plate shape, and a ring that binds the multiple elements in a state in which their postures are arranged in an annular shape, and the elements are pressed by sequentially pressing the other elements preceding the element. In a pressure transmission belt that transmits power between two pulleys, when performing the power transmission, the circumferential length of the ring is expanded so as to suppress an increase in a gap between the adjacent elements. A pressing power transmission belt, wherein the element is thermally expanded by heat generated by power transmission.   The element is formed of a plurality of materials having different linear expansion coefficients between a main material forming a main portion of the element having a relatively small linear expansion coefficient and a thermal expansion material having a relatively large linear expansion coefficient. The press-type power transmission belt according to claim 1.   The pressure transmission belt according to claim 2, wherein at least one surface of the element facing other elements adjacent to each other before and after the element is formed of the thermal expansion material.

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