JP2011017389A - Power transmission belt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission belt of a unitary construction having high rigidity, durability and flexibility.SOLUTION: The power transmission belt is formed of a belt-shaped annular element having predetermined rigidity and elasticity and is wound around a pair of pulleys for belt transmission between the pair of pulleys. The power transmission belt is provided with outer slits 6 which are opened toward an outer peripheral side in a radial direction of the annular element 1 and have grooves cut from the outer peripheral side toward an inner peripheral side in the radial direction throughout a width direction of the annular element 1, and inner slits 7 which are opened toward the inner peripheral side and have grooves cut from the inner peripheral side toward the outer peripheral side throughout the width direction. The outer slits 6 and the inner slits 7 are formed so that they are situated alternately at a predetermined pitch p in a circumferential direction of the annular element 1 and a sum of the groove depth deo of the outer slits 6 and the groove depth dei of the inner slits 7 is larger than the thickness th of the annular element 1 in the radial direction.

Description

  The present invention relates to a power transmission belt that is wound around a pair of pulleys and performs belt transmission between the pulleys.

  As an example of a device to which a belt transmission device composed of a pair of pulleys and a power transmission belt is applied, there is a belt type continuously variable transmission. Generally, this belt type continuously variable transmission changes the effective diameter of the pulley, that is, the radius around which the belt is wound, by changing the groove width of the pulley around which the belt is wound, thereby setting the transmission ratio steplessly. It is a transmission that can Accordingly, the driving side (or input side) pulley and the driven side (or output side) pulley are constituted by a fixed sheave and a movable sheave that moves back and forth in the axial direction with respect to the fixed sheave. The belt is configured such that the belt winding radius can be continuously changed by changing the groove width of each pulley, that is, the gear ratio can be continuously changed.

  As a belt used in such a belt type continuously variable transmission, a pressing type pressing belt (so-called push belt) is known. This type of pressing belt aligns metal plate-like pieces (hereinafter referred to as elements) called elements or blocks, that is, the metal elements face each other with their postures aligned, and are adjacent to each other in an annular shape. And the elements are bound by a metal annular member (hereinafter referred to as a ring) called a ring, a hoop, or a band. Both left and right side surfaces of the element are formed in a V-shape, and the V-shaped portion is a so-called flank surface, and is configured to contact the inner surface of the V groove in the pulley and transmit torque here. .

  When the pressing 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. When the pulley rotates in this state, the element sandwiched between the pulleys rotates with the pulley, but the pressing belt is stretched between the driving pulley and the driven pulley, so the so-called linear portion The element is pushed out of the pulley and presses the preceding 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 with the driven pulley to transmit torque to the driven pulley.

  As described above, the pressing belt used in the belt-type continuously variable transmission mainly includes a number of metal elements and a ring that binds the elements. Therefore, it has high rigidity and strength or durability, and has flexibility that can be wound around a pulley. Therefore, by using such a metal pressing belt for a belt-type continuously variable transmission, the belt-type continuously variable transmission is applied as a transmission for an automobile that requires high durability and a large torque capacity. It is possible. On the other hand, the metal pressure belt as described above is constructed by assembling the ring and several hundred elements, so that the manufacturing cost is relatively high, and there is a slight slip between the element and the ring. Will inevitably occur, so the transmission efficiency will decrease accordingly. Further, since the pulley is usually made of a metal material, the contact portion between the pulley and the pressing belt is a contact between metals, and noise and vibration are relatively increased.

  On the other hand, for example, a rubber belt reinforced with fibers, wires or the like is usually used as a V belt used in a belt transmission device including a pair of V pulleys having a V-shaped groove and a V belt. Such a rubber V-belt is inferior in rigidity, strength or durability as compared with the above-described metal pressing belt, but it is an integrated structure as a finished product, so that it looks like a metal pressing belt. Such inevitable slip does not occur, and relatively good transmission efficiency can be obtained. In addition, it has high elasticity, flexibility, and vibration damping ability due to its rubber characteristics, so it can be smoothly wound around the V pulley and absorbs shocks and vibrations during operation well. Power transmission can be performed.

  An example of such a V-belt is described in Patent Document 1. The double cogged V belt described in Patent Document 1 includes an endless core wire embedded portion having a core wire embedded so as to form a spiral having a predetermined pitch in the belt width direction, and an inner peripheral side of the core wire embedded portion A lower cog forming portion having a lower cog formed at a constant pitch along the belt longitudinal direction, and an upper portion formed on the outer peripheral side of the core wire embedded portion and formed at a constant pitch along the belt longitudinal direction. A belt between adjacent upper cogs, wherein the distance from the bottom of the groove extending in the belt width direction between adjacent lower cogs to the core wire is 2.0 to 2.3 mm. The distance from the bottom of the groove extending in the width direction to the core wire is configured to be 1.2 to 2.0 mm. In Patent Document 1, as a specific example in which the double cogged V belt as described above is applied to a transmission of a two-wheeled vehicle, a polyester fiber, an aramid fiber, etc. A rubber V-belt in which a formed core wire is embedded and integrally formed is disclosed.

JP 2003-329088 A

  Since the rubber-made V-belt described in Patent Document 1 is excellent in flexibility and vibration damping capability as described above, belt transmission can be performed efficiently and smoothly. However, the rubber V-belt as described above is lower in strength and rigidity than the metal pressure belt described above, and is a belt type continuously variable for automobiles that require high rigidity and durability and a large torque capacity. It was difficult to apply to a transmission.

  The present invention has been made paying attention to the above technical problem, and has high rigidity and durability applicable to, for example, a belt type continuously variable transmission for automobiles, and flexible flexibility when wound on a pulley. And a power transmission belt having an integral structure with good transmission efficiency.

  In order to achieve the above object, the invention of claim 1 is formed by a belt-like annular body having predetermined rigidity and elasticity, and is wound around a pair of pulleys to transmit a belt between the pair of pulleys. In the power transmission belt, an outer slit that opens toward the outer circumferential side in the radial direction of the annular body and that has a groove cut from the outer circumferential side toward the inner circumferential side in the radial direction over the entire width direction of the annular body; And an inner slit that opens toward the inner peripheral side and cuts a groove from the inner peripheral side toward the outer peripheral side over the entire width direction, and the outer slit and the inner slit are The sum of the groove depth of the outer slit and the groove depth of the inner slit is alternately positioned at a predetermined pitch in the circumferential direction of the annular body. It is a power transmission belt according to claim which is formed to be larger than the thickness of the.

  The invention according to claim 2 is the power transmission belt according to claim 1, wherein an annular band member is slidably attached to the outer periphery of the annular body. is there.

  According to a third aspect of the present invention, in the second aspect of the present invention, a curved surface that is curved so that a central portion in the width direction is convex toward the outer peripheral side is formed on the contact surface of the outer peripheral portion with the band member. The power transmission belt according to claim 2, wherein the power transmission belt is formed.

  According to a fourth aspect of the present invention, in the invention of the second or third aspect, the contact surface is located on the outer peripheral side with respect to the position of the groove bottom of the outer slit in the radial direction and the position of the groove bottom of the inner slit. It is a power transmission belt formed at a position closer to the inner circumference than the above.

  Further, the invention of claim 5 is the invention according to any one of claims 1 to 4, wherein the annular body is opened on both the left and right side surfaces in the width direction facing the left and right outer sides in the width direction, respectively. The power transmission belt is provided with left and right axial slits that are grooved from the left and right side surfaces toward the central portion in the width direction over the entire radial direction so as to be positioned at a predetermined pitch in the circumferential direction. It is.

  The invention of claim 6 is the invention according to any one of claims 1 to 5, wherein the outer slit and the inner slit are portions of the linear state when a part of the annular body is in a linear state. The power transmission belt is formed so that the groove width of the outermost peripheral portion of the outer slit is narrower than the groove width of the innermost peripheral portion of the inner slit.

  According to a seventh aspect of the present invention, in the invention according to any one of the first to sixth aspects, the annular body is formed by curving and holding an annularly formed member integrally formed with a line having ends. It is a power transmission belt.

  The invention according to an eighth aspect is the invention according to the seventh aspect, wherein the annular body is formed by curving a member integrally formed into a line shape with ends and holding the member annularly with the band member. A power transmission belt including

  A ninth aspect of the present invention is the power transmission belt according to any one of the first to sixth aspects, wherein the annular body is formed by a member integrally formed in an endless annular shape.

  According to the first aspect of the present invention, the outer slit and the inner slit are formed in the band-shaped annular body having predetermined rigidity and elasticity, so that the rigidity and the integrity as a continuous body are maintained. As a belt, a power transmission belt to which flexibility when traveling while being wound around a pulley is added is configured. Therefore, ensure sufficient rigidity and strength as a power transmission belt used in a belt transmission device that requires high rigidity and durability and a large torque capacity, such as a belt type continuously variable transmission for automobiles. Can do. Further, by forming each slit with an appropriate number and pitch to give the annular body appropriate flexibility, smooth belt transmission with reduced noise and vibration can be performed. Since the power transmission belt is configured as an integral structure belt, loss due to relative slip between the separate members of the belt does not occur, and therefore belt transmission can be performed with good transmission efficiency.

  According to the invention of claim 2, the band member is attached to the outer peripheral portion of the annular member forming the power transmission belt, whereby the strength against the tension provided by the band member is added to the annular member and the annular member is provided. Is reinforced. Alternatively, the tension of the band member is applied to the annular body. Therefore, the strength and durability of the power transmission belt against tension can be improved. Alternatively, the tension of the power transmission belt can be increased, and as a result, the transmission torque capacity of the belt transmission device using this power transmission belt can be increased.

  According to the invention of claim 3, the band member is centered at the central portion in the width direction of the annular body when the power transmission belt travels. In other words, the center in the width direction of the band member is aligned with the center in the width direction of the annular body. Therefore, it can be prevented that the band member is eccentric with respect to the center in the width direction of the annular body and the side surface of the band member comes into contact with a part of the pulley or the annular body. It is possible to avoid a decrease in durability of the belt transmission device used.

  According to the invention of claim 4, the position on the outer peripheral side with respect to the position of the groove bottom of the outer slit in the radial direction of the annular body and the position on the inner peripheral side with respect to the position of the groove bottom of the inner slit, that is, the upper slit and the lower A contact surface that contacts the inner peripheral surface of the band member is formed at a position within a range where the side slits overlap in the radial direction of the annular body. In the power transmission belt according to the present invention, the center position in the radial direction in the range where the upper slit and the lower slit overlap in the circumferential direction of the annular body is when the power transmission belt is wound around the pulley and travels. Since it becomes a running radius, the diameter of the annular body of the contact surface is formed by forming the contact surface at a position within the range where the upper slit and the lower slit overlap in the radial direction of the annular body as described above. The position in the direction is the position near the running radius. That is, the distance between the traveling radius in the radial direction of the annular body and the position of the contact surface is short or almost zero. Therefore, when the power transmission belt travels, the moment acting on the band member due to the frictional force between the band member and the annular body can be reduced or made almost zero, and is generated by the moment acting on the band member. The relative slip between the band member and the annular body to be performed can be suppressed. As a result, the friction loss due to the relative slip as described above can be reduced and the transmission efficiency of the power transmission belt can be improved.

  According to the invention of claim 5, the axial slits are formed on the left and right side surfaces of the annular body, whereby the annular body that is curved in the width direction can be easily deformed. That is, when the power transmission belt is wound around the pulley and travels, meandering that deforms so that the power transmission belt undulates to the left and right in the width direction with respect to the traveling direction becomes easy. For this reason, for example, even when a misalignment occurs between two pulleys, the power transmission belt can easily absorb the displacement between the pulleys due to meandering, and excessive stress is generated in the power transmission belt. The durability can be improved by preventing this. In addition, since it becomes easy to absorb the impact and vibration when the power transmission belt is wound around the pulley, smooth belt transmission with reduced noise and vibration can be performed.

  According to the invention of claim 6, the groove width of the upper slit is narrower than that of the lower slit in the portion where the power transmission belt does not wrap around any pulley and the annular body is in a straight line state. By being formed in this way, the curvature in the direction in which the groove width of the upper slit is narrower than the curvature in the direction in which the groove width of the lower slit is narrowed is suppressed. That is, so-called reverse warping in the direction in which the power transmission belt is detached from the pulley is suppressed with respect to the curvature in the direction in which the power transmission belt is wound around the pulley. Therefore, when the power transmission belt is running, the linear variation of the power transmission belt can be suppressed from continuously moving up and down in the radial direction or the thickness direction, that is, so-called string vibration, and noise and vibration can be reduced smoothly. Belt transmission can be performed.

  According to the invention of claim 7, the annular body is formed by curving and holding the linear molded body having an integral structure in an annular shape. That is, first, a linear member having an integral structure is manufactured by being integrally molded, and the power transmission belt is formed by holding it in a ring shape using a predetermined method or a predetermined member. Therefore, the power transmission belt can be easily manufactured, and the manufacturing cost of the power transmission belt can be suppressed. In addition, as a linear member with ends, for example, a plurality of types having different lengths can be manufactured by integrally molding a member having a sufficient length and cutting it into a desired length. Can be easily manufactured. Therefore, a plurality of types of power transmission belts having different diameters or power transmission belts having arbitrary diameters can be easily manufactured, and the productivity of the power transmission belt can be improved.

  According to the invention of claim 8, the end-shaped linear member can be easily formed by installing the band member on the outer peripheral portion in the state where the linear member integrally formed is curved in an annular shape. The power transmission belt can be easily manufactured.

  According to the invention of claim 9, the annular body is formed by a molded body having an integral structure. Therefore, it is possible to manufacture the power transmission belt by integrally molding it, in other words, to easily manufacture the power transmission belt without assembling a plurality of members or bending the linear members and connecting them in an annular shape. This can reduce the manufacturing cost of the power transmission belt.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram for demonstrating the structure in 1st Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a schematic diagram for demonstrating the structure in 2nd Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a schematic diagram for demonstrating the structure in 3rd Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a schematic diagram for demonstrating the structure in 4th Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a schematic diagram for demonstrating the structure in 5th Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a schematic diagram for demonstrating the structure in 6th Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a schematic diagram for demonstrating the structure in 7th Example of the power transmission belt which concerns on this invention, Comprising: (a) is a perspective view which shows a part of the power transmission belt, (b) is the power transmission. It is the top view which looked at the belt from the outer peripheral surface side of radial direction, (c) is the side view which looked at the power transmission belt from the side surface side of the width direction. It is a figure which shows typically an example of the belt-type continuously variable transmission which can apply the power transmission belt which concerns on this invention.

  Next, the present invention will be described with reference to specific examples. The power transmission belt targeted by the present invention is used in a belt-type continuously variable transmission as an example, and is sandwiched in a winding groove having a V-shaped cross section formed on the outer periphery of a pulley. As a result, the torque is transmitted by the frictional force generated between the pulleys. One example is schematically shown in FIG. 8, and the belt B is wound around a pair of driving pulleys Pp and driven pulleys Ps that constitute a belt-type continuously variable transmission. Each of these pulleys Pp, Ps is configured by disposing a fixed sheave and a movable sheave each having a tapered surface, and a winding groove V having a V-shaped cross section is formed between these sheaves. Yes. The movable sheave is configured to change the width of the winding groove V by moving the movable sheave back and forth with respect to the fixed sheave by an actuator A such as a hydraulic cylinder.

  The belt B according to the present invention used in this way has a predetermined rigidity and elasticity, and is formed in an annular shape as a whole, and the left and right side surfaces in the width direction are V-shaped or tapered. The belt-shaped or band-shaped annular body is formed. Below, the specific structural example of the belt B which concerns on this invention is demonstrated.

(First embodiment)
FIG. 1 shows a first embodiment of the configuration of the power transmission belt B according to the present invention. In FIG. 1, the belt B is constituted by an annular body 1. The annular body 1 is integrally formed in an annular shape from a material having a predetermined rigidity and elasticity, such as metal or hard resin. For example, when the belt B is applied to a belt-type continuously variable transmission as described above, the predetermined rigidity is a rigidity that can withstand the clamping pressure received from the pulleys Pp and Ps without being deformed, or a pressing belt. Rigidity that can withstand the compressive load without deformation. The predetermined elasticity is, for example, a state in which the belt B is wound around the pulleys Pp and Ps and is smoothly wound around the pulleys Pp and Ps and a linear state between the pulleys Pp and Ps. It is elastic that can be restored to its original state without being plastically deformed when it is repeatedly deformed to a state where a compressive load or tensile load is applied.

  Specifically, the annular body 1 has a cross section perpendicular to the circumferential direction of the annular body 1 (the direction indicated by the arrow ci in FIG. 1), and the outer circumference in the radial direction of the annular body 1 (the direction indicated by the arrow ra in FIG. 1). 1 is formed in a trapezoidal shape with the end 2 on the side (upper side in FIG. 1A) as a long side and the end 3 on the inner peripheral side (lower side in FIG. 1B) as a short side. ing. The trapezoidal angle of the trapezoidal cross section, that is, the angle formed by the side surfaces 4 and 5 on the left and right (or upper and lower) sides in the width direction of the annular body 1 (the direction indicated by the arrow wi in FIG. 1), It is formed to be substantially equal to the opening angle of the winding groove V of the pulleys Pp and Ps to be hung. Therefore, this belt B is configured as a V belt of pulleys (V pulleys) Pp, Ps having a V-shaped winding groove V, that is, a power transmission belt B that performs belt transmission between a pair of pulleys Pp, Ps. Yes.

  A plurality of outer slits 6 and inner slits 7 are formed on both the outer peripheral side and the inner peripheral side of the annular body 1. The outer slit 6 opens toward the outer peripheral side of the annular body 1 and has a shape in which a groove having a predetermined groove width br and groove depth deo is cut from the outer peripheral side to the inner peripheral side over the entire width direction. Is formed. The plurality of outer slits 6 are formed at substantially equal intervals at a predetermined pitch p1 over the entire circumferential direction of the annular body 1. On the other hand, the inner slit 7 opens toward the inner peripheral side of the annular body 1 and cuts a groove having a predetermined groove width br and groove depth dei from the inner peripheral side to the outer peripheral side over the entire width direction. It is formed in a different shape. The plurality of inner slits 7 are formed at substantially equal intervals with a predetermined pitch p 1 over the entire circumferential direction of the annular body 1, similarly to the outer slit 6. The pitch p1 of each of the slits 6 and 7 is set to an appropriate size for realizing the flexibility desired for the belt B.

  The outer slits 6 and the inner slits 7 are alternately arranged in the circumferential direction of the annular body 1. That is, the outer slit 6 and the inner slit 7 are arranged such that the phase of the pitch p1 is shifted by, for example, a half pitch, and the positions of the outer slit 6 and the inner slit 7 are not overlapped in the circumferential direction of the annular body 1. Yes. The groove depths deo and dei are set so that the sum of the groove depth deo of the outer slit 6 and the groove depth dei of the inner slit 7 is larger than the thickness th in the radial direction of the annular body 1. The slits 6 and 7 are respectively formed by being set.

  Therefore, the outer slit 6 and the inner slit 7 do not interfere with each other, and the tip portions of the grooves formed in the radial direction of the annular body 1, that is, the groove bottoms 6 a and 7 a portions are arranged in the circumferential direction of the annular body 1. It overlaps. Therefore, the annular body 1, that is, the belt B of the present invention is continuous as a part where the outer slit 6 and the inner slit 7 overlap in the circumferential direction, and is configured as an annular integral structure. That is, since the belt B of the present invention is not configured with a plurality of separate members, relative slip or the like does not occur between the plurality of members during traveling, for example.

  As described above, the annular body 1 is formed from a material having a predetermined rigidity and elasticity such as metal or hard resin. For example, when the annular body 1 is formed using a metal as a material, the slits 6 and 7 are formed by machining on the material formed as an annular integrated member by forging, for example. The annular body 1, that is, the belt B can be formed as an integral structure.

  Further, when the annular body 1 is formed using a synthetic resin such as hard plastic, for example, the annular body 1 as an annular integrated structure having the slits 6 and 7 as described above, for example, by injection molding. The belt B can be formed.

  As described above, according to the power transmission belt B in the first embodiment, the outer slit 6 and the inner slit 7 are formed in the belt-like annular body 1 having predetermined rigidity and elasticity. A power transmission belt B to which flexibility when traveling while being wound around pulleys Pp, Ps, etc. is added while maintaining the integrity as a continuous body. Therefore, sufficient rigidity and strength are secured as a power transmission belt B used in a belt transmission device that requires high rigidity and durability and a large torque capacity, such as a belt type continuously variable transmission for an automobile. be able to.

  In addition, by forming the slits 6 and 7 with an appropriate quantity and pitch p1 so that the annular body 1 has appropriate flexibility, smooth belt transmission with reduced noise and vibration can be performed. Since the power transmission belt B is configured as an integral structure belt, there is no loss due to relative slip between the separate members in the belt B, so that belt transmission can be performed with good transmission efficiency. Can do.

(Second embodiment)
FIG. 2 shows a second embodiment of the configuration of the power transmission belt B according to the present invention. The first embodiment described above is an example in which the power transmission belt B is constituted by only the integral-structured annular body 1, whereas this second embodiment comprises the power transmission belt B and the integral-structure annular body. It is the example comprised from the band member which reinforces. The annular body in the second embodiment is common to the configuration of the annular body 1 in the first embodiment except for some shapes. Therefore, for the annular body in the second embodiment, the same reference numerals as those in FIG. 1 are assigned to the same parts as those in the first embodiment, and the detailed description thereof is omitted.

  In FIG. 2, the belt B in the second embodiment includes an annular body 20 and a band member 21 that is slidably attached to an outer peripheral portion of the annular body 20. The basic shape of the annular body 20 is the same as that of the annular body 1 in the first embodiment described above, but the outer peripheral surface of the annular body 20 is formed when the annular band member 21 is mounted. The contact member 20a is in contact with the inner peripheral surface of the band member 21, and the central portion in the width direction of the contact surface 20a is curved so as to be convex toward the outer peripheral side. A curved surface 20b having a crown on the contact surface 20a is formed. 2 illustrates an example in which the entire contact surface 20a is a curved surface 20b that is curved in an arc shape in the width direction. However, the contact surface 20a is partially curved at the center in the width direction of the contact surface 20. The surface 20b may be formed.

  The band member 21 is an annular member having a predetermined strength made of, for example, metal. The predetermined strength is a strength that improves the strength of the annular body 20 in the tension direction when the band member 21 is attached to the annular body 20 to constitute the belt B, or a tension is applied to the annular body 20 to increase the annular strength. It is the strength that can increase the tension of the body 20.

  The band member 21 is slidably mounted on the contact surface 20a of the annular body 20, that is, the curved surface 20b. Specifically, the band member 21 is not fixed to the annular body 20 but is held in a state of being wound around the outer peripheral portion of the annular body 20 by the tension of the band member 21 itself. Thus, the annular body 20 and the band member 21 constitute the power transmission belt B in the second embodiment of the present invention.

  Thus, according to the power transmission belt B in the second embodiment, the band member 21 is attached to the outer peripheral portion of the annular body 20 forming the power transmission belt B, whereby the tension that the band member 21 has. Is added to the annular body 20 to reinforce the annular body 20. Alternatively, the tension of the band member 21 is applied to the annular body 20. Therefore, the strength and durability of the power transmission belt B against tension can be improved. Alternatively, the tension of the power transmission belt B can be increased, and as a result, the transmission torque capacity of the belt transmission device using the power transmission belt B can be increased.

  In addition, the crown-shaped curved surface 20 b is formed on the contact surface 20 a of the annular body 20, whereby the band member 21 is centered at the center portion in the width direction of the annular body 20 when the power transmission belt B is traveling. That is, the centering in the width direction of the band member 21 is aligned with the center in the width direction of the annular body 20. Therefore, it is possible to prevent the band member 21 from being eccentric with respect to the center in the width direction of the annular body 20 and the side surface of the band member 21 abutting against the pulleys Pp, Ps or a part of the annular body 20. It is possible to avoid a decrease in durability of the belt B and the belt transmission device using the power transmission belt B.

  When the centering function for the band member 21 as described above is not required, the annular body 20 in which the crown-shaped curved surface 20b is not formed on the contact surface 20a, that is, the annular body 1 in the first embodiment described above is used. Is also possible. That is, the power transmission belt B can be configured by attaching the band member 21 to the outer peripheral portion of the annular body 1 in the first embodiment.

(Third embodiment)
FIG. 3 shows a third embodiment of the configuration of the power transmission belt B according to the present invention. The second embodiment described above is an example in which the band member 21 that supports the annular body 20 is mounted on the outer peripheral portion of the annular body 20, that is, the outermost peripheral surface of the annular body 20, whereas this third embodiment has a width. This is an example in which a band member 21 is mounted on the bottom surface of a recess having a recess formed at the center in the direction. Regarding the annular body in the third embodiment, the same configuration as the first embodiment and the configuration of the band member 21 similar to the second embodiment are the same as FIG. 1 and FIG. Reference numerals are attached and detailed description thereof is omitted.

  In FIG. 3, the belt B in the third embodiment includes an annular body 30 in which a recess 31 is formed and a band member 21 that is slidably mounted in the recess 31 of the annular body 30. . The outer shape of the annular body 30 is basically the same as that of the annular body 1 in the first embodiment described above, but the band member 21 is accommodated inside the central portion in the width direction of the annular body 30. A recess 31 is formed.

  The recess 31 is open in the outer circumferential direction of the annular body 30, and has a shape in which a central portion in the width direction of the annular body 30 is cut by a concave groove over the entire circumferential direction of the annular body 30. The opening width of the recess 31 is set wider than the width of the band member 21 so that the band member 21 can be accommodated in the recess 31. The bottom surface of the recess 31 is a contact surface 31a that comes into contact with the inner peripheral surface of the band member 21 when the band member 21 is mounted, and a central portion in the width direction of the contact surface 31a is convex toward the outer peripheral side. In other words, a curved surface 31b having a crown on the contact surface 31a of the annular body 30 with the band member 21 is formed.

  The contact surface 31 a is formed on the outer peripheral side with respect to the position of the groove bottom 6 a of the outer slit 6 in the radial direction of the annular body 30 and on the inner peripheral side of the position of the groove bottom 7 a of the inner slit 7. In other words, the contact surface 31a is formed at substantially the same position as the radial position of the portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction.

  A portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction, that is, a portion where the annular body 30 is continuous in the circumferential direction, is when the belt B runs around the pulleys Pp and Ps. It is the part that becomes the running radius or its vicinity. Therefore, as described above, the position in the radial direction of the contact surface 31a is formed at substantially the same position as the position in the radial direction of the portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction. When the band member 21 is attached to the annular body 30, the band member 21 is disposed at the same position as the traveling radius in the radial direction or in the vicinity thereof. Therefore, when the belt B travels around the pulleys Pp and Ps, the moment acting on the band member 21 is reduced by the frictional force between the band member 21 and the annular body 30, and the moment acts. The relative slip between the band member 21 and the annular body 30 generated by the above is suppressed.

  Thus, according to the power transmission belt B in the third embodiment, the outer peripheral side of the annular slit 30 in the radial direction of the outer slit 6 and the position of the groove bottom 7a of the inner slit 7 from the position of the groove bottom 6a. The contact surface 31a that contacts the inner peripheral surface of the band member 21 is located at a position on the inner peripheral side, that is, in a range where the upper slit 6 and the lower slit 7 overlap in the radial direction of the annular body 30. It is formed. Therefore, the distance between the traveling radius in the radial direction of the annular body 30 and the position of the contact surface 31a becomes short or almost zero, and the band member 21 and the annular body 30 are moved when the power transmission belt B travels. The moment acting on the band member 21 by this frictional force can be made small or almost zero. As a result, it is possible to suppress the relative slip between the band member 21 and the annular body 30 caused by the moment acting on the band member 21, and reduce the friction loss due to the relative slip, thereby reducing the power transmission belt B. The transmission efficiency can be improved.

  Further, the crown-shaped curved surface 31b is formed on the contact surface 31a of the annular body 30, in other words, the contact surface 31a is formed as the crown-shaped curved surface 31b. The band member 21 is centered at the central portion in the width direction of the annular body 30. In other words, the center in the width direction of the band member 21 is aligned with the center in the width direction of the annular body 30. Therefore, it can be prevented that the band member 21 is eccentric with respect to the center in the width direction of the annular body 30 and the side surface of the band member 21 comes into contact with the pulley Pp, Ps or the inner wall surface of the concave portion 31 of the annular body 20. Further, it is possible to avoid a decrease in durability of the power transmission belt B and the belt transmission device using the power transmission belt B.

(Fourth embodiment)
FIG. 4 shows a fourth embodiment of the configuration of the power transmission belt B according to the present invention. The third embodiment described above is an example in which the band member 21 is mounted on the bottom surface of the concave portion 31 with respect to the annular body 30 in which the concave portion 31 is formed in the central portion in the width direction. These are the examples which formed the recessed part which each accommodates a band member in the both right and left side surfaces of a cyclic | annular body. As for the annular body in the fourth embodiment, the same configuration as that of the first and third embodiments and the configuration of the band member 21 similar to those of the second and third embodiments are shown in FIG. The same reference numerals as those in FIG. 1 to FIG.

  In FIG. 4, the belt B according to the fourth embodiment includes an annular body 40 in which concave portions 43 and 44 for receiving band members 41 and 42 are formed on both left and right side surfaces 4 and 5 in the width direction, and the annular body. The two band members 41 and 42 are slidably mounted in the respective concave portions 43 and 44 of the 40.

  The band members 41 and 42 are formed of an annular member having a predetermined strength made of metal, for example, in the same manner as the band member 21 described above. The band members 41 and 42 are slidably mounted on the inner wall surface on the inner peripheral side in the radial direction of the concave portions 43 and 44 of the annular body 40. Specifically, the band members 41 and 42 are not fixed to the annular body 40 and are wound around the recesses 43 and 44 of the annular body 40 by the tension of the band members 41 and 42 themselves. Is held by.

  The recesses 43 and 44 are opened in the outer direction of the respective side surfaces 4 and 5 on the left and right sides in the width direction of the annular body 40, and the central portion of the thickness in the radial direction of the annular body 40 is the circumferential direction of the annular body 40 It has a shape that is recessed and cut into a concave shape throughout. The opening width of each recess 43, 44 is wider than the thickness of each band member 41, 42 so that each band member 41, 42 can be accommodated in each recess 43, 44. The groove depth is set sufficiently deeper than the width of each band member 41, 42 so that each band member 41, 42 can be completely accommodated in each recess 43, 44.

  The position of each of the recesses 43 and 44 in the radial direction of the annular body 40 is the central portion of the thickness in the radial direction of the annular body 40 as described above. And the inner slit 7 are substantially the same position as the position in the radial direction where the circumferential slits overlap.

  That is, the inner wall surface on the inner circumferential side in the radial direction of each of the concave portions 43 and 44 has contact surfaces 43a, which come into contact with the inner circumferential surfaces of the respective band members 41, 42 when the respective band members 41, 42 are mounted. 44a. The contact surfaces 43a and 44a are both on the outer peripheral side with respect to the position of the groove bottom 6a of the outer slit 6 in the radial direction of the annular body 40 and on the inner peripheral side with respect to the position of the groove bottom 7a of the inner slit 7. Formed in position. In other words, the radial positions of the contact surfaces 43a and 44a are substantially the same as the radial positions of the portions where the outer slit 6 and the inner slit 7 of the annular body 40 overlap in the circumferential direction. Each recess 43, 44 is formed.

  As described above, in the portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction, that is, the portion where the annular body 40 is continuous in the circumferential direction, the belt B is wound around the pulleys Pp and Ps. It is a part which becomes the running radius at the time of running or its vicinity. Therefore, as described above, the radial positions of the contact surfaces 43a and 44a are formed at substantially the same position as the radial position of the portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction. Thus, when the band members 41 and 42 are respectively attached to the annular body 40, the band members 41 and 42 are disposed at the same position as the traveling radius in the radial direction or in the vicinity thereof. Therefore, when the belt B travels around the pulleys Pp and Ps, the moment acting on the band members 41 and 42 by the frictional force between the band members 41 and 42 and the annular body 40 is reduced. Relative slippage between the band members 41 and 42 and the annular body 40 generated by the action of the moment is suppressed.

  Thus, according to the power transmission belt B in the fourth embodiment, the outer peripheral side of the annular slit 40 in the radial direction of the annular slit 40 and the position of the groove bottom 7a of the inner slit 7 from the position of the groove bottom 6a. Also, the inner circumferential surfaces of the two band members 41 and 42 are positioned at the inner circumferential position, that is, within the range where the upper slit 6 and the lower slit 7 overlap in the radial direction of the annular body 40. Contact surfaces 43a and 44a that come into contact with each other are formed. Therefore, the distance between the traveling radius in the radial direction of the annular body 40 and the position of each contact surface 43a, 44a is shortened or substantially zero, and when the power transmission belt B travels, The moment acting on each of the band members 41 and 42 by the frictional force with the annular body 40 can be made small or almost zero. As a result, it is possible to suppress the relative slip between the band members 41 and 42 and the annular body 40 caused by the moment acting on the band members 41 and 42, and reduce the friction loss due to the relative slip. Thus, the transmission efficiency of the power transmission belt B can be improved.

  According to the power transmission belt B in the fourth embodiment, the recesses 43 and 44 to which the two band members 41 and 42 are attached are respectively opened on the left and right side surfaces 4 and 5 of the annular body 40. To be formed. Therefore, when the band members 41 and 42 are attached to the annular body 40, the band members 41 and 42 may be fitted from the outside of the left and right side surfaces 4 and 5 of the annular body 4. , 42 can be easily mounted in the recesses 43, 44 of the annular body 40. That is, the power transmission belt B including the annular body 40 and the two band members can be easily configured.

(5th Example)
FIG. 5 shows a fifth embodiment of the configuration of the power transmission belt B according to the present invention. The fifth embodiment is an example in which axial slits are formed on the left and right side surfaces of the annular body constituting the power transmission belt B in consideration of the lateral deformation of the power transmission belt B in the width direction. The annular body in the fifth embodiment is common to the configuration of the annular body 1 in the first embodiment described above except for some shapes. Therefore, for the annular body in the second embodiment, the same reference numerals as those in FIG.

  In FIG. 5, the belt B in the fifth embodiment is constituted by an annular body 50. The basic shape of the annular body 50 is the same as that of the annular body 1 in the first embodiment described above, but the left and right axial slits 51 are respectively provided on the left and right side surfaces 4 and 5 of the annular body 50. , 52 are formed.

  Each of the axial slits 51 and 52 opens to the left and right outer sides in the width direction of the annular body 50, and extends from the left and right side surfaces 4 and 5 to the center portion in the width direction over the entire radial direction of the annular body 50. It is formed in a shape with a groove cut. The left and right axial slits 51 and 52 are formed at substantially equal intervals with a predetermined pitch p2 over the entire circumferential direction of the annular body 50.

  The groove width and groove depth of each of the axial slits 51 and 52 are such that the strength of the annular body 50 does not drop below the required strength, and the integrity of the annular body 50 as a continuous body is impaired. Each is set to an appropriate size so that there is no Therefore, the portion of the annular body 50 where the axial slits 51 and 52 are formed has a lower strength of the annular body 50 within a range not lower than the required strength, and is easily deformed accordingly. Therefore, the annular body 50 is easily deformed in a direction in which the groove width of each of the axial slits 51 and 52 is changed, that is, the deformation in which the annular body 50 is curved left and right in the width direction.

  Although the left and right axial slits 51 and 52 are shown as being arranged at substantially equal intervals with a predetermined pitch p2, the left and right axial slits 51 and 52 are left and right. The arrangement may be such that the pitch is different. Further, like the outer and inner slits 6 and 7, the left and right axial slits 51 and 52 may overlap in the circumferential direction of the annular body 50.

  Thus, according to the power transmission belt B in the fifth embodiment, the annular slits 51 and 52 are formed on the left and right side surfaces 4 and 5 of the annular body 50 so that the annular body is curved in the width direction. 50 deformation is facilitated. That is, when the power transmission belt B travels while being wound around the pulleys Pp and Ps, the power transmission belt B can be easily meandered so as to be undulated to the left and right in the width direction with respect to the traveling direction. Therefore, for example, even when a misalignment occurs between the pulleys Pp and Ps, the displacement between the pulleys Pp and Ps can be easily absorbed by the power transmission belt B meandering easily. As a result, it is possible to prevent an excessive stress from being generated in the power transmission belt B and improve the durability of the power transmission belt B. Further, since the power transmission belt B can easily absorb the shock and vibration when the power transmission belt B is wound around the pulleys Pp and Ps, smooth belt transmission with reduced noise and vibration can be performed.

(Sixth embodiment)
FIG. 6 shows a sixth embodiment of the configuration of the power transmission belt B according to the present invention. The sixth embodiment is an example of a configuration in which the groove width of the outer slit is narrower than the groove width of the inner slit in order to prevent reverse warping of the power transmission belt B in a linear state. The annular body in the sixth embodiment is common to the configuration of the annular body 1 in the first embodiment described above except for some shapes. Therefore, for the annular body in the sixth embodiment, the same reference numerals as those in FIG. 1 are attached to the same parts as those in the first embodiment, and the detailed description thereof is omitted.

  In FIG. 6, the belt B in the sixth embodiment is constituted by an annular body 60. The basic shape of the annular body 60 is the same as that of the annular body 1 in the first embodiment described above, but on the outer peripheral side of the annular body 60, the outer slit of the annular body 1 in the first embodiment described above is provided. Instead of 6, an outer slit 61 is formed. The outer slit 61 opens toward the outer peripheral side of the annular body 60, and cuts a groove having a predetermined groove width br 'and a groove depth deo from the outer peripheral side toward the inner peripheral side over the entire width direction. It is formed into a shape. The plurality of outer slits 61 are formed at substantially equal intervals with a predetermined pitch p1 over the entire circumferential direction of the annular body 60. On the other hand, the inner slit 7 is the same as the inner slit 7 of the annular body 1 in the first embodiment described above, opens toward the inner peripheral side of the annular body 60, and extends from the inner peripheral side over the entire width direction. It is formed in a shape in which a groove having a predetermined groove width br and groove depth dei is cut toward the outer peripheral side.

  The outer slit 61 is formed such that the groove width br 'is narrower than the groove width br of the inner slit 7. Therefore, the annular body 60 in the sixth embodiment has a groove in the outer slit 61 that has a degree of freedom of bending in a direction in which the groove width br of the inner slit 7 is narrowed, that is, in a direction in which the outer peripheral side of the annular body 60 is convex. The degree of freedom of bending in the direction in which the width br ′ is narrowed, that is, in the direction in which the inner peripheral side of the annular body 60 is convex, is small.

  As described above, according to the power transmission belt B in the sixth embodiment, the lower slit 7 is formed in a portion where the annular body 60 is in a straight state without the power transmission belt B being wound around the pulleys Pp and Ps. By forming the groove width br ′ of the upper slit 61 to be narrower than the groove width br, the groove width br ′ of the upper slit 61 is larger than the curve in the direction in which the groove width br of the lower slit 7 is narrowed. Bending in the narrowing direction is suppressed. That is, so-called reverse warpage in the direction in which the power transmission belt B is detached from the pulleys Pp and Ps is suppressed with respect to the curvature in the direction in which the power transmission belt B is wound around the pulleys Pp and Ps. Therefore, when the power transmission belt B travels, it is possible to suppress continuous fluctuations in which the linear portion of the power transmission belt B moves up and down in the radial direction or thickness direction, that is, so-called string vibration, and noise and vibration are reduced. Smooth belt transmission can be performed.

(Seventh embodiment)
FIG. 7 shows a seventh embodiment of the configuration of the power transmission belt B according to the present invention. In the first to sixth embodiments described above, the annular members constituting the power transmission belt B are all integrally formed in an annular shape, whereas this seventh embodiment is integrally formed in a linear shape. This is an example in which the annular member constituting the power transmission belt B is configured by curving and holding the member in an annular shape by, for example, the same band member 21 as in the second embodiment described above. Regarding the annular body in the seventh embodiment, there is a difference in whether the initial molding state is linear or annular, but the configuration of each part such as the cross-sectional shape and the shape of each slit is the same as in the first embodiment. The configuration is the same as that of the annular body 1 in FIG. 3 or the annular body 30 in the third embodiment. Therefore, regarding the annular body in the seventh embodiment, the same configuration as that of the first and third embodiments described above and the configuration of the band member 21 similar to those of the second and third embodiments described above are shown in FIG. Are denoted by the same reference numerals as in FIGS. 1 to 3 and their detailed description is omitted.

  In FIG. 7, the belt B in the seventh embodiment includes an annular body 70 and a band member 21. The annular body 70 is formed of a material having a predetermined rigidity and elasticity, such as metal and hard resin, for example, similarly to the annular bodies 1 and 30 in the first and third embodiments described above. The annular body 70 is formed by curving a member integrally formed in a line shape with ends in an annular shape, and being held in an annular shape by, for example, the band member 21 in the second and third embodiments described above. Is formed.

  Specifically, the annular body 70 is formed with a recess 71 that accommodates the band member 21 in the central portion in the width direction of the annular body 70, similarly to the annular body 30 in the third embodiment described above. . The recess 71 is formed so as to open in the outer circumferential direction of the annular body 70, and a central portion in the width direction of the annular body 70 is formed as a concave groove over the entire circumferential direction of the annular body 70. The opening width of the recess 71 is set wider than the width of the band member 21 so that the band member 21 can be accommodated in the recess 71. Further, the bottom surface of the recess 71 is a contact surface 71a that comes into contact with the inner peripheral surface of the band member 21 when the band member 21 is mounted. Similar to the annular body 30 in the third embodiment, a curved surface may be formed on the contact surface 71a so that the central portion in the width direction is convex toward the outer peripheral side.

  Further, as described above, the annular body 70 is configured by holding an integrally formed end-like linear member in an annular shape, and therefore, the annular body 70 is a part in the circumferential direction. Furthermore, it has the end surface 70a and the end surface 70b which mutually oppose in the circumferential direction. In other words, the annular body 70 is formed of a linear or rod-shaped member having an integral structure having both end surfaces 70a and 70b as both ends, and the linear or rod-shaped member is annularly formed so that the end surfaces 70a and 70b face each other. The band member 21 is attached and held in an annular shape.

  Therefore, the radial dimension of the annular body 70 formed thereafter is set according to the length (longitudinal dimension) of the original linear or rod-shaped member having the end face 70a and the end face 70b as both ends. That is, the annular body 70 having a desired diameter can be formed by appropriately adjusting the length of the original linear or rod-shaped member.

  And the contact surface 71a is the outer peripheral side from the position of the groove bottom 6a of the outer slit 6 in the radial direction of the annular body 70 and the groove bottom of the inner slit 7 in the same manner as the annular body 30 in the third embodiment described above. It is formed at a position closer to the inner periphery than the position 7a. In other words, the contact surface 71a is formed at substantially the same position as the radial position of the portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction.

  Therefore, as described above, the radial position of the contact surface 71a is formed at substantially the same position as the radial position of the portion where the outer slit 6 and the inner slit 7 overlap in the circumferential direction. When the band member 21 is mounted to hold the annular body 70 in an annular shape, the band member 21 is disposed at the same position as the traveling radius in the radial direction or in the vicinity thereof. Therefore, when the belt B travels around the pulleys Pp and Ps, the moment acting on the band member 21 is reduced by the frictional force between the band member 21 and the annular body 70, and the moment acts. The relative slip between the band member 21 and the annular body 70 generated by the above is suppressed.

  Thus, according to the power transmission belt B in the seventh embodiment, the annular body 70 is formed by curving a linear or rod-shaped member of an integral structure and holding it in an annular shape by the band member 21. That is, first, a power transmission belt B is formed by integrally manufacturing a linear or bar-shaped member having an integral structure and holding it in an annular shape using the band member 21. Therefore, the power transmission belt B can be easily manufactured. For example, the manufacturing cost can be reduced as compared with a conventional metal pressure belt composed of a large number of elements and rings.

  In addition, as a linear or rod-shaped member having ends, a plurality of members having different lengths are manufactured by integrally molding a sufficiently long member and cutting it into a desired length. Various types or arbitrary lengths can be easily manufactured. Therefore, a plurality of types of power transmission belts B having different diameters or power transmission belts B having an arbitrary diameter can be easily manufactured, and the productivity of the power transmission belt can be improved.

  The present invention is not limited to the specific examples described above. That is, in the above-described specific example, the case where the power transmission belt B according to the present invention is used in a belt-type continuously variable transmission is described as an example. However, the power transmission belt B according to the present invention is a belt-type continuously variable transmission. Not only a continuously variable transmission but also a belt for power transmission in another winding transmission device (belt transmission device) constituted by a belt and a pulley.

  1, 20, 30, 40, 50, 60, 70 ... annular body, 6, 61 ... outer slit, 7 ... inner slit, 21, 41, 42 ... band member, 20a, 31a, 44a, 71a ... contact surface, 20b , 31b: curved surface, 51, 52: axial slit, B: power transmission belt.

Claims (9)

In a power transmission belt formed of a belt-like annular body having predetermined rigidity and elasticity, wound around a pair of pulleys and performing belt transmission between the pair of pulleys,
An outer slit that opens toward the outer peripheral side in the radial direction of the annular body and that has a groove from the outer peripheral side toward the inner peripheral side in the radial direction over the entire width direction of the annular body, and the inner peripheral side And an inner slit that is cut from the inner peripheral side toward the outer peripheral side over the entire width direction is provided,
The outer slit and the inner slit are alternately positioned at a predetermined pitch in the circumferential direction of the annular body, and the sum of the groove depth of the outer slit and the groove depth of the inner slit is in the radial direction. A power transmission belt, wherein the power transmission belt is formed to be larger than the thickness of the annular body.   The power transmission belt according to claim 1, wherein an annular band member is slidably attached to the outer peripheral portion of the annular body.   The power transmission belt according to claim 2, wherein a curved surface that is curved so that a central portion in the width direction is convex toward the outer peripheral side is formed on a contact surface of the outer peripheral portion with the band member.   The said contact surface is formed in the said outer peripheral side rather than the position of the groove bottom part of the said outer side slit in the said radial direction, and the said inner peripheral side position rather than the position of the groove bottom part of the said inner side slit. The power transmission belt described in 1.   The left and right sides of the annular body are opened to the left and right side surfaces in the width direction so as to open to the left and right outer sides in the width direction and to be positioned at a predetermined pitch in the circumferential direction. The power transmission belt according to any one of claims 1 to 4, wherein left and right axial slits each having a groove cut from a surface toward a central portion in the width direction are provided.   The outer slit and the inner slit have a groove width of an outermost peripheral portion of the outer slit in a portion in the linear state when a part of the annular body is in a linear state. 6. The power transmission belt according to claim 1, wherein the power transmission belt is formed so as to be narrower than the groove width.   The power transmission belt according to any one of claims 1 to 6, wherein the annular body is formed by curving and holding a member integrally formed in a linear shape with ends.   The power transmission belt according to claim 7, wherein the annular body is formed by curving a member integrally formed in a line shape with ends and holding the member annularly with the band member.   The power transmission belt according to any one of claims 1 to 6, wherein the annular body is formed by a member integrally formed in an endless annular shape.

Images