JP2006046581A - Endless belt for transmission and belt type continuously variable transmission using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the strength of a pin by bringing the pin into contact with a pulley at the closest position to a center of a pin end face in the whole range of a change gear ratio, and to reduce the noise of a belt. <P>SOLUTION: Both ends 4a, 4b of the pin 4 have curved faces curved in the belt advancing direction. In under-drive (U/D), a straight line S as a center line of a radius of curvature in curving the curved faces of the pin 4 is inclined in the clockwise direction to the radial direction L of the pulley having a radius passing a center of the pin 4, and the pin 4 is brought into contact with the pulley 10 at a contact area a at a front side in the belt advancing direction with respect to the radial direction L. In a change gear ratio of 1.0, the straight line S is agreed with the radial direction L, and the pin 4 is brought into contact with the pulley 10 at a contact area b on a straight line in parallel with the straight line S on an end 4a of the pin 4. In over drive (O/D), the straight line S is inclined in the anticlockwise direction to the radial direction L, and the pin 4 is brought into contact with the pulley 10 at a contact area c at a rear side in the belt advancing direction with respect to the radial direction L. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a technical field of a transmission endless belt for transmitting torque and a belt-type continuously variable transmission using the same, and more specifically, it is wound around two pulleys arranged in parallel shafts to transmit torque between both pulleys. Therefore, the present invention relates to a technical field of a transmission endless belt in which a link plate is connected in an endless chain shape by pins and a belt-type continuously variable transmission using the same.

  As one type of continuously variable transmission (CVT), two pulleys with parallel shaft arrangement (in this specification, the torque input side is a primary pulley, the torque output side is a secondary pulley, and the case where both pulleys are common are simply called pulleys) There is a belt-type continuously variable transmission that transmits torque by connecting between them with an endless belt for transmission. Both pulleys in this transmission are arranged so that a pair of conical disc-shaped sheaves face each other with respect to the rotating shaft so that the apexes of the sheaves face each other. It has a structure in which an endless belt for transmission is wound around the wall).

  As an example of this type of transmission endless belt, a large number of link plates are used, and adjacent link plates are connected to each other by joints to make them endless, and this joint is made a relatively long strip plate pin and slightly shorter than this pin. In addition, a transmission endless belt has been proposed in which the belt is formed of a strip-shaped strip, the pin is disposed behind the strip in the belt traveling direction, and both ends of the pin are in contact with a pair of pulley wall surfaces. (For example, refer to Patent Document 1).

  According to the transmission endless belt disclosed in Patent Document 1, a force due to torque from the primary pulley is transmitted to the pin, and the pin presses the link plate through the strip by this force, whereby the transmission endless belt rotates. Move. And in a secondary pulley, a pin rotates a secondary pulley, A torque is transmitted from a primary pulley to a secondary pulley via an endless belt for transmission. At this time, the pin is a strength member because both ends of the pin come into contact with a pair of pulley wall surfaces of both pulleys, and a force acts between the pin and both pulleys. Since the force does not act between the pin and both pulleys by not contacting the pair of pulley wall surfaces, they are not strength members. Therefore, the strip thickness can be reduced, and the link plate pitch can be reduced.

  As another example of an endless belt for transmission, a number of link plates are used, and adjacent link plates are connected to each other with a joint made of a pair of pins to make them endless, and both ends of the pins are formed into curved surfaces. An endless belt for transmission configured by bringing these curved surfaces into contact with a pair of pulley wall surfaces has been proposed (for example, see Patent Document 2).

According to the transmission endless belt disclosed in Patent Document 2, by changing the shape of the frictional contact portion between the pin and the pulley wall surface, wear of the transmission endless belt is reduced and the pin enters the pulley. Impact can be reduced.
JP-A-8-312725. JP 2000-230606 A.

  By the way, in the transmission endless belt, the pitch circle radius (the rotation radius at the pulley) of the transmission endless belt varies depending on the transmission gear ratio, so the pin viewed from the side of the belt when the pin enters the pulley and is engaged The slope of changes with the gear ratio. And if the inclination of a pin changes, the contact position with the pulley on the both end surfaces of a pin will also change. In this case, the larger the pitch circle radius, the more the pin is inclined outward in the radial direction of the pulley with respect to the belt traveling direction, and the contact position between the pin and the pulley moves backward in the belt traveling direction. Because the pulley wall surface and the pin are inclined in the pulley radial direction with respect to the pulley axis vertical direction, when the pin is inclined backward, the long part in the longitudinal direction of the pin above and behind the pin is ahead of the vicinity of the center of the pin. It is because it becomes the same as a pulley wall surface space | interval, and contacts those pulley wall surfaces. On the contrary, when the pins are tilted forward, the long portions in the longitudinal direction of the pins on the upper and front sides of the pins become the same as the pulley wall surface distance before the vicinity of the center of the pins and come into contact with the pulley wall surfaces.

Thus, when the contact position of a pin and a pulley changes, there exists a problem that durability of a pin falls. Therefore, in order to improve the durability of the pin, it is advantageous in terms of strength of the pin to make contact with the pulley near the center of both end faces of the pin.
In consideration of noise, it is advantageous to contact the pulley on the front side of the pin in the belt traveling direction. The reason is that if the pin is engaged with the pulley in front of the link plate, the vertical vibration of the belt called the so-called polygonal effect can be reduced.

  However, in the transmission endless belts disclosed in the above-mentioned Patent Documents 1 and 2, the pulley and the pin end surface are focused on the relative relationship between the pulley and the slope of the curved surface of the pin end surface according to such a change in the gear ratio. A good relationship with the curved surface has not been found in consideration of both durability and quietness.

  Therefore, the present invention can provide an advantage in the strength of the pin by making contact with the pulley as close to the center of the pin end surface as possible in the entire range of the gear ratio, and reduce the noise of the belt. Even if the pulley contact position on the pin end surface moves depending on the belt endless belt for transmission, the pin end surface shape can be set to be favorable with respect to the pulley so that it moves as far forward as possible in the belt traveling direction. An object of the present invention is to provide a belt type continuously variable transmission using the above-described belt.

  In order to solve the above-mentioned problems, the transmission endless belt of the invention of claim 1 is a transmission endless belt that is wound around two pulleys and transmits torque between the pulleys, and includes a plurality of link plates, In an endless belt for transmission consisting of a curved surface as a contact surface with a pulley wall surface and connecting adjacent link plates to each other to be endless, the curved surface of the pin end surface is generally curved in the belt traveling direction. And the straight line that becomes the center of curvature when machining the curved surface on the end surface of the pin is radially outward of the pulley when the pin is engaged with the pulley during underdrive (U / D), and It is set to incline forward in the belt traveling direction.

  Further, the transmission endless belt of the invention of claim 2 is set so that the straight line coincides with the radial direction of the pulley within a speed ratio of 1.0 to overdrive (O / D). It is characterized by.

  Further, the transmission endless belt of the invention of claim 3 is a transmission endless belt which is wound around two pulleys and transmits torque between the pulleys, and has a plurality of link plates and pulleys with curved end surfaces. In the endless belt for transmission consisting of a contact surface with the wall surface and a pin that connects the adjacent link plates to each other to be endless, the curved surface of the pin end surface is curved in a direction substantially perpendicular to the belt traveling direction, The straight line that becomes the center of curvature when processing the curved surface on the pin end surface is the front side in the belt traveling direction and the radial direction of the pulley when the pin is engaged with the pulley during underdrive (U / D). It is set to incline inward.

  Further, the transmission endless belt of the invention of claim 4 is set such that the straight line coincides with the tangential direction of the pulley within a speed ratio of 1.0 to overdrive (O / D). The transmission endless belt according to claim 3.

  Further, the transmission endless belt of the invention of claim 5 is a transmission endless belt that is wound around two pulleys and transmits torque between the pulleys, and has a plurality of link plates and pulleys with curved end surfaces. In a transmission endless belt comprising a contact surface with a wall surface and an endless link by connecting adjacent link plates to each other, the curved surface of the pin end surface is either in the belt traveling direction or in a direction substantially perpendicular to the belt traveling direction. When the curved surface curved in the belt traveling direction is machined on the pin end surface, the curvature radius curved in the belt traveling direction is larger than the curvature radius curved in the perpendicular direction. The straight line that is the center of curvature of the pin is located outside the pulley in the radial direction when the pin is engaged with the pulley during underdrive (U / D). If the radius of curvature that is set to incline forward in the belt traveling direction and is curved in the perpendicular direction is larger than the radius of curvature that curves in the belt traveling direction, the curve that curves in the perpendicular direction to the pin end surface The straight line that becomes the center of curvature when machining the surface is inclined forward in the belt traveling direction and radially inward of the pulley when the pin is engaged with the pulley during underdrive (U / D). It is characterized by being set to.

  Further, in the transmission endless belt according to the sixth aspect of the present invention, when the radius of curvature that curves in the belt traveling direction is larger than the radius of curvature that curves in the perpendicular direction, the transmission ratio changes from 1.0 to overdrive (O / The straight line of the curved surface that curves in the belt traveling direction within the range of D) is set to coincide with the radial direction of the pulley, and the curvature radius that curves in the perpendicular direction curves in the belt traveling direction. When larger than the radius of curvature, the straight line of the curved surface that curves in the vertical direction within the range of 1.0 to overdrive (O / D) is set to coincide with the tangential direction of the pulley. It is characterized by.

  Further, the transmission endless belt of the invention of claim 7 is a transmission endless belt that is wound around two pulleys and transmits torque between the pulleys, and has a plurality of link plates and pulleys with curved end surfaces. In an endless belt for transmission comprising a contact surface with a wall surface and an endless link by connecting adjacent link plates to each other, the curved surface of the pin end surface is generally curved in the belt traveling direction, and the curved surface Is formed of a plurality of radii of curvature, and when the curved surface having the largest curvature radius is machined on the end surface of the pin, the straight line serving as the center of curvature is the pin when the underdrive (U / D) is performed. In the state where it is engaged with the pulley, the pulley is set so as to incline radially outward of the pulley and forward in the belt traveling direction.

  Further, the transmission endless belt of the invention of claim 8 is a transmission endless belt that is wound around two pulleys to transmit torque between the pulleys, and has a plurality of link plates and pulleys with curved end surfaces. In an endless belt for transmission comprising a contact surface with a wall surface and a pin that connects adjacent link plates to each other to be endless, the curved surface of the pin end surface is curved in a direction substantially perpendicular to the belt traveling direction. The curvature of the curved surface is composed of a plurality of radii of curvature, and when the curved surface having the largest radius of curvature is machined on the pin end surface, the straight line that becomes the center of curvature is at the time of underdrive (U / D) The pin is set so as to incline forward in the belt traveling direction and radially inward of the pulley in a state where the pin is engaged with the pulley.

  Furthermore, the transmission endless belt of the invention of claim 9 is characterized in that an inclination angle at which the straight line is inclined is set to be larger than 0 degree and within 15 degrees.

  Furthermore, a belt type continuously variable transmission according to a tenth aspect of the present invention is characterized by comprising at least the transmission endless belt according to any one of the first to ninth aspects.

  According to the present invention configured as described above, when the curved surface of the pin end surface is generally curved in the belt traveling direction, the straight line that becomes the center of curvature when the curved surface is processed into the pin end surface is represented by U / D. Since the pin is sometimes set to be inclined radially outward of the pulley and forward in the belt traveling direction when the pin is engaged with the pulley, the pin comes into contact with the pulley in front of the U / D. Therefore, even if the contact position between the pin and the pulley moves rearward as described above while shifting from U / D to O / D, the contact position only moves to a position after the center of the pin. As a result, the pin can come into contact with the pulley in the vicinity of its center in the entire range of the gear ratio, so that an advantageous effect on the strength of the pin can be obtained.

  Further, by setting the inclination angle at which the straight line is inclined to be greater than 0 degree and within 15 degrees, the straight line and the radial direction of the pulley can be made to coincide with each other between the gear ratios 1.0 to O / D in the normal range. it can. Thereby, the contact area between the pin and the pulley can be maximized, and an advantageous effect in terms of the strength of the pin can be obtained. In that case, since the inclination of the pin usually changes by about 15 degrees in the range from U / D to O / D, a sufficient effect can be obtained by providing the inclination in this range.

  Further, in the range where the pitch circle radius is smaller than the pitch circle radius where the straight line and the radial direction of the pulley coincide (the transmission ratio is large), the straight line is inclined forward than the radial direction of the pulley, and the contact position between the pin and the pulley is also Front side. Therefore, noise and noise can be reduced. Furthermore, by setting the inclination to be large and setting the O / D so that the straight line and the radial direction of the pulley coincide with each other, the pulley can be brought into contact with the pulley before the center of the pin in the entire gear ratio. Can be obtained.

  On the other hand, according to the present invention, when the curved surface of the pin end surface is curved in a direction substantially perpendicular to the belt traveling direction, the straight line that becomes the center of curvature when the curved surface is processed into the pin end surface is (U / D) When the pin is engaged with the pulley at the time of U / D), it is set to incline forward in the belt traveling direction and radially inward of the pulley, so that the inclination angle at which the straight line inclines is larger than 0 degree and within 15 degrees By setting to, the straight line and the tangential direction of the pulley can coincide with each other between the gear ratios 1.0 to O / D in the normal range. Thereby, the contact area between the pin and the pulley can be maximized, and an advantageous effect in terms of the strength of the pin can be obtained.

Further, in the range where the pitch circle radius is smaller than the pitch circle radius where the straight line and the tangential direction of the pulley coincide (the transmission ratio is large), the straight line is inclined forward than the radial direction of the pulley, and the contact position between the pin and the pulley is also Front side. Therefore, noise and noise can be reduced. Furthermore, by making the inclination large and setting the O / D so that the straight line and the tangential direction of the pulley coincide with each other, the pulley can be brought into contact with the pulley before the center of the pin in the entire transmission gear ratio. Can be obtained.
Also in this case, as in the case where the curved surface of the pin end surface is curved in the belt traveling direction, the pin comes into contact with the pulley in front of the belt during U / D. The same effect as when bent in the traveling direction can be obtained.

  Further, according to the present invention, when the curved surface of the pin end surface is curved in either of the belt traveling direction and the direction substantially perpendicular to the belt traveling direction, the curvature radius curved in the belt traveling direction is vertical. When the radius of curvature is larger than the radius of curvature, the pin engages the pulley during underdrive (U / D) with the straight line that becomes the center of curvature when machining the curved surface that curves in the belt traveling direction on the end surface of the pin. If the radius of curvature that curves in the vertical direction is larger than the radius of curvature that curves in the belt traveling direction, set the belt on the end surface of the pin. When machining a curved surface that curves in a direction perpendicular to the direction of travel, the pin bites into the pulley during underdrive (U / D) on the straight line that becomes the center of curvature. Since it is set to incline toward the front side of the belt in the belt traveling direction and radially inward of the pulley in a state where the radius of curvature is larger, the one with the larger radius of curvature has substantially the same effect as the flat surface. An effect can be obtained.

  Furthermore, according to the present invention, when the curvature of the curved surface at the end of the pin is composed of a plurality of radii of curvature, a straight line that becomes the center of curvature when machining the curved surface with the largest curvature radius on the pin end surface, When the pin is engaged with the pulley during U / D, it is set to incline forward in the belt traveling direction and radially inward of the pulley, so that the straight line with the largest curvature radius satisfies the above-mentioned condition The aforementioned effects can be obtained. This is because in order to increase the contact area between the pin and the pulley and improve the wear durability, the end of the pin and the pulley are set in contact with each other at the location where the radius of curvature is the largest in the same curve. . For example, the case where the curvature radius for chamfering only the peripheral part of the end surface of a pin is made small can be considered.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a partial side view showing a part of a transmission endless belt according to an example of an embodiment of the present invention, and FIG. 2 is a partial plan view showing a part of this transmission endless belt as viewed from the outer peripheral side.
As shown in FIGS. 1 and 2, the transmission endless belt 1 of this example is used for a belt-type continuously variable transmission, and includes a primary pulley (not shown) on a torque input side and arranged on parallel shafts. The belt is stretched between a secondary pulley (not shown) on the torque output side and travels in a belt traveling direction α indicated by an arrow in FIG. 1, that is, rotates clockwise. FIG. 1 shows a portion where the transmission endless belt 1 is wound around the primary pulley.

  When the distance between the opposing pulley wall surfaces of the pair of sheaves constituting the primary pulley is increased, the interval between the opposing pulley wall surfaces of the pair of sheaves constituting the secondary pulley is reduced, and conversely the primary pulley is constituted. The distance between the pulley wall surfaces of each pulley is synchronized so that the distance between the opposite pulley wall surfaces of the pair of sheaves constituting the secondary pulley becomes larger when the distance between the opposite pulley wall surfaces of the pair of sheaves becomes smaller. Thus, continuously variable transmission is performed. In the following description, when it is common to the primary pulley and the secondary pulley, it is simply referred to as a pulley.

  The transmission endless belt 1 includes a large number of link plates 2 and a large number of joints 3 that connect adjacent link plates 2 to each other to make them endless. Each joint 3 has a strip plate-like pin 4 having a relatively long length in the direction perpendicular to the belt traveling direction α (vertical direction in FIG. 2) and a length in the same direction slightly shorter than these pins 4. It comprises a strip-like strip 5. Each link plate 2 is interposed between a first plate set 6 composed of five link plates 2 aligned in a direction orthogonal to the belt traveling direction α and the link plate 2 of the first plate set 6. The second plate set 7 including the four link plates 2 provided is provided together.

  The first plate sets 6 and the second plate sets 7 are alternately arranged in the belt traveling direction α. In that case, the belt traveling direction front side portion 2f of each link plate 2 of the first plate set 6 and each link plate 2 of the second plate set 7 adjacent to the first plate set 6 on the downstream side in the belt traveling direction. A part of the rear end 2r is overlapped in a direction orthogonal to the belt traveling direction α, and the belt traveling direction rear end 2r of each link plate 2 of the first plate set 6 and the first plate set 6 A part of each link plate 2 of the second plate set 7 adjacent to the upstream side in the belt traveling direction is overlapped with the belt traveling direction front side portion 2f in the same manner.

  The joint 3 is penetrated in a direction orthogonal to the belt traveling direction α in each hole 8, 9 formed in the overlapping portion of each link plate 2 of the first plate set 6 and each link plate 2 of the second plate set 7. ing. In that case, the pin 3 of the joint 3 is arranged on the rear side of the strip 5 (upstream side in the belt traveling direction).

FIG. 3 shows the pin 4, (A) is a front view, (B) is a plan view (top view), and (C) is a left side view.
In this example, both ends 4a and 4b of the pin 4 of the joint 3 are the same as the inclination angles of both pulley wall surfaces 10c and 10d facing each other of the pair of sheaves 10a and 10b of the pulley 10 as shown in FIG. In addition to the inclined angle, the curved surface is curved in the belt traveling direction α as shown in FIG. This curved surface is an arc surface of a circle having a radius R centered on the point P when the pin 4 is viewed in a direction orthogonal to both the belt traveling direction α and the rotation axis of the pulley 10 (that is, in a top view). Is formed. Therefore, in this specification, the curve in the belt traveling direction α means that the pins 4 protrude toward the opposite pulley wall surfaces 10c, 10c in the direction from one edge to the other edge in the belt traveling direction α. It means to bend (the same applies to claims).

The point P is on the radius of curvature center line S when the ends 4a and 4b of the pin 4 are curved. In this case, the straight line S is inclined to the front side in the belt traveling direction on the radially outer side with respect to the radial direction of the pulley 10 in a state where the pin 4 is engaged with the endless belt 1 for transmission during underdrive (U / D). Set to. In this case, the inclination angle is preferably set to be larger than 0 degree and within 15 degrees. The portions of the circular arc surfaces of both ends 4a and 4b of the pin 4 that protrude to the maximum toward the wall surfaces 10c and 10d are contact ends that contact the wall surfaces 10c and 10d of the pulley 10, respectively.
On the other hand, since the strip 5 is formed shorter than the pin 4, both ends 5 a and 5 b of the strip 5 are not in contact with the left and right pulley wall surfaces 10 c and 10 d of the pulley 10.

  The operation of the transmission endless belt 1 of this example configured as described above will be described. When the primary pulley rotates clockwise, torque is transmitted from both pulley wall surfaces 10c and 10d of the pulley 10 to the pin 4 that contacts the pulley wall surfaces 10c and 10d. Then, the pin 4 tries to rotate clockwise, and the belt traveling direction front side portion 2f of the link plate 2 through which the pin 4 passes is pressed through the strip 5 on the front side of the pin 4. As a result, the link plate 2 tends to rotate in the same direction, so the rear side portion 2r of the link plate 2 in the belt traveling direction presses the pin 4 in contact with the link plate 2 in the same direction. For this reason, as described above, the pin 4 presses the belt travel direction front side portion 2f of the link plate 2 adjacent to the link plate 2 on the upstream side in the belt travel direction via the strip 4. Since the link plates 2 are sequentially pressed in this way, the transmission endless belt 1 rotates clockwise.

  When the transmission endless belt 1 rotates in the clockwise direction, torque is transmitted to the secondary pulley from the pin 4 that contacts both pulley wall surfaces of the secondary pulley, and the secondary pulley rotates in the clockwise direction. Thus, torque is transmitted from the primary pulley to the secondary pulley via the transmission endless belt 1 and output from the secondary pulley. At this time, torque is transmitted at a torque ratio based on the pitch radius of the transmission endless belt 1 wound around the primary pulley and the pitch circle radius of the transmission endless belt 1 wound around the secondary pulley.

  By the way, in the transmission endless belt 1 of this example, the contact position between the pin 4 and the pulley 10 changes due to the difference in pitch circle radius. This is because, as the pitch circle radius increases, the angle of the adjacent ring plate 2 when the transmission endless belt 1 is wound on the pulley 10 becomes smaller, so the pin 4 tilts backward in the direction opposite to the belt traveling direction α. It is to do. The above-described change in the contact position based on the difference in pitch circle radius will be described.

  The pin 4 has no curvature in the direction orthogonal to the straight line S. Further, since the surfaces of the pulley wall surfaces 10c and 10d of the pulley 10 are inclined with respect to the rotation axis of the pulley 10, the end surfaces of both ends 4a and 4b of the pin 4 are also different from the surfaces of the pulley wall surfaces 10c and 10d as described above. It is similarly inclined. Accordingly, the smaller the pitch circle radius, the narrower the interval between the sheaves 10a, 10b of the pulley 10. In this way, when the pitch circle radius of the pulley 10 is small, the pin 4 tilts forward. However, when the pin 4 tilts forward, the pin longitudinal width on the front side in the belt traveling direction of both end faces of the pin 4 is increased. Since the distance between the wall surfaces of the pulley wall surfaces 10c and 10d of the pulley 10 becomes the same as that before the center of the pin, the front side in the belt traveling direction of the end surfaces of both ends 4a and 4b comes into contact with the pulley 10 first. Further, when the pitch circle radius of the pulley 10 is large, the pin 4 tilts backward. However, when the pin 4 tilts backward, the width in the longitudinal direction of the pin on the rear side in the belt traveling direction of the end faces of both ends 4a and 4b. Since the distance between the wall surfaces of the pulley wall surfaces 10c and 10d of the pulley 10 becomes the same as that before the center of the pin, the rear side in the belt traveling direction of the end surfaces of both ends 4a and 4b comes into contact with the pulley 10 first.

  Therefore, as shown in FIG. 4A, when the pitch circle radius is small and the pin 4 is tilted forward, that is, the straight line S is clockwise with respect to the radial direction L of the pulley indicating the radius passing through the center of the pin 4. In this case, the contact area a between the end surfaces of both ends 4a and 4b of the pin 4 and the pulley wall surfaces 10c and 10d of the pulley 10 is the front side in the belt moving direction (front side of the pin) from the radial direction L. In the region a, the pin 4 comes into contact with the pulley 10. Further, as shown in FIG. 4B, when the pin 4 is neither forwardly inclined nor backwardly inclined, that is, when the straight line S is coincident with the radial direction L, both ends 4a, 4b of the pin 4 are used. The pulley 10 is in contact with the pulley 10 in a straight line contact area b somewhere parallel to the straight line S. The contact is brought into a surface state by the pressing pressure of the pulley 10, and at this time, the pin 10 and the pulley 4 come into contact with each other at the maximum area. Further, as shown in FIG. 4C, when the pitch circle radius is large and the pin 4 is inclined backward, that is, when the straight line S is inclined counterclockwise with respect to the radial direction L, the pin The contact region c between the end surfaces of both ends 4a and 4b of the roller 4 and the pulley wall surfaces 10c and 10d of the pulley 10 is on the rear side in the belt traveling direction (the rear side of the pin) from the radial direction L. Come into contact with.

  The straight line S can be set so that the gear ratio of the continuously variable transmission coincides with the radial direction of the pulley 10 within the range of 1.0 to overdrive (O / D). Is set to coincide with the radial direction of the pulley 10.

  According to the transmission endless belt 1 of this example, the curved surfaces of the end surfaces 4a and 4b of the pin 4 are generally curved in the belt traveling direction, and the curved surfaces are processed into the end surfaces of the both ends 4a and 4b of the pin 4. Since the straight line S, which is the center of curvature, is set to be inclined outwardly in the radial direction L of the pulley 10 and forward in the belt traveling direction when the pin 4 is engaged with the pulley 10 during U / D. The pin 4 comes into contact with the pulley 10 in front of the U / D. Therefore, even if the contact position between the pin 4 and the pulley 10 moves rearward as described above while shifting from U / D to O / D, the contact position only moves to a position after the center of the pin 4. . As a result, the pin 4 can come into contact with the pulley 10 in the vicinity of the center in the entire range of the gear ratio, so that an advantageous effect in terms of strength of the pin 4 can be obtained.

  Further, by setting the inclination angle at which the straight line S is inclined to be greater than 0 degree and within 15 degrees, the straight line and the radial direction of the pulley 10 are made to coincide with each other between the gear ratios 1.0 to O / D in the normal range. be able to. Thereby, the contact area of the pin 4 and the pulley 10 can be maximized, and an advantageous effect in terms of strength of the pin 4 can be obtained. In that case, since the inclination of the pin 4 usually changes by about 15 degrees in the range from U / D to O / D, a sufficient effect can be obtained by providing the inclination in this range.

  Further, in a range in which the pitch circle radius is smaller than the pitch circle radius in which the straight line S and the radial direction of the pulley 10 coincide with each other (the transmission ratio is large), the straight line S is inclined forward relative to the radial direction of the pulley 10. The contact position with the pulley 10 is also on the front side. Therefore, noise and noise can be reduced. Further, by setting a large inclination and setting so that the straight line S and the radial direction of the pulley 4 coincide with each other at O / D, the pulley 10 can be brought into contact with the pulley 10 before the center of the pin 4 in the entire speed ratio. Therefore, the transmission endless belt 1 excellent in silence can be obtained.

5A to 5C show a pin 4 of another example of the embodiment of the present invention, and are respectively a front view, a plan view, and a left side view similar to FIGS. 3A to 3C. It is.
In this example, both ends 4a and 4b of the pin 4 of the joint 3 are substantially equal to the inclination angles of the pulley wall surfaces 10c and 10d facing each other of the pair of sheaves 10a and 10b of the pulley 10, respectively, as shown in FIG. In addition to the same inclination angle, the curved surface is curved in a direction perpendicular to the belt traveling direction α as shown in FIG. This curved surface is formed by a circular arc surface having a radius R with the point P as the center when the pin 4 is viewed in the belt traveling direction α (that is, in a front view). Therefore, in this specification, to bend in a direction perpendicular to the belt traveling direction α means that the pins 4 protrude toward the facing sheaves 10a and 10b in the direction from the upper edge to the lower edge in the belt traveling direction α. (The same applies to the description of the scope of claims).

This point P is on the radius of curvature center line G when the both ends 4a and 4b of the pin 4 are bent. In this case, the straight line G is set to be inclined inward in the radial direction on the front side in the belt traveling direction with respect to the tangential direction of the pulley 10 when the pin 4 is engaged with the transmission endless belt 1 at the time of U / D. In this case, the inclination angle is preferably set to be larger than 0 degree and within 15 degrees. And the part which protrudes toward the pulley wall surfaces 10c and 10c at the maximum of the circular arc surface of both ends 4a and 4b of the pin 4 is set as the contact end which contacts the wall surfaces 10c and 10d of the pulley 10, respectively.
Note that the straight line G ′ shown in FIG. 5C is parallel to the straight line G, and when the straight line G coincides with the pulley tangential direction, the pulley 10 and the end faces of both ends 4a and 4b of the pin 4 are closest. It is a straight line. That is, the pulley 10 and the end surfaces of both ends 4a and 4b of the pin 4 are in contact with each other in the vicinity of the straight line G ′.

  Incidentally, also in the transmission endless belt 1 of this example, the contact position between the pin 4 and the pulley 10 changes due to the difference in pitch circle radius. This is because the larger the pitch circle radius, the smaller the angle of the adjacent ring plate 2 when the transmission endless belt 1 is wound around the pulley 10, and the pin 4 tilts backward. The above-described change in the contact position based on the difference in pitch circle radius will be described.

  The pin 4 has no curvature in the direction orthogonal to the straight line G. Further, since the surfaces of the pulley wall surfaces 10c and 10d of the pulley 10 are inclined with respect to the rotation axis of the pulley 10, the end surfaces of both ends 4a and 4b of the pin 4 are also different from the surfaces of the pulley wall surfaces 10c and 10d as described above. It is similarly inclined. Therefore, the smaller the pitch radius, the narrower the interval between the sheaves 10a, 10b of the pulley 10. For this reason, when the pitch circle radius of the pulley 10 is small, the end surfaces of both ends 4a and 4b of the pin 4 come into contact with the pulley 10 at positions close to the straight line G 'and on the inner diameter side of the pitch circle radius.

  Therefore, as shown in FIG. 6A, when the pitch circle radius is small and the pin 4 is tilted forward, that is, the straight lines G and G ′ are tangential to the tangential direction L ′ at the radius of the pulley passing through the center of the pin 4. In the case of tilting clockwise, the contact area d between the end surfaces of both ends 4a, 4b of the pin 4 and the pulley wall surfaces 10c, 10d of the pulley 10 is near the straight line G ′ in the front direction of the belt travel from the radial direction L ( The pin 4 comes into contact with the pulley 10 in this contact area d. As shown in FIG. 6B, when the pin 4 is neither tilted forward nor backward, that is, when the straight lines G and G ′ coincide with the tangential direction L ′, the straight line G ′. The pulley 10 is brought into contact with the contact region e near the upper center. Further, as shown in FIG. 6C, when the pitch circle radius is large and the pin 4 is inclined backward, that is, when the straight lines G and G ′ are inclined counterclockwise with respect to the tangential direction L ′. The contact region f between the end surfaces of both ends 4a and 4b of the pin 4 and the pulley wall surfaces 10c and 10d of the pulley 10 is the rear side in the belt traveling direction (the rear side of the pin) from the radial direction L near the straight line G ′. The pin 4 comes into contact with the pulley 10 in the contact region f.

  The straight line G can be set so that the transmission gear ratio of the continuously variable transmission coincides with the tangential direction of the pulley 10 within a range of 1.0 to O / D. Set to match the tangent direction.

  According to the transmission endless belt 1 of this example, the curved surfaces of the end surfaces 4a and 4b of the pin 4 are curved in a direction substantially perpendicular to the belt traveling direction α, and the curved surfaces are formed on the end surfaces of the both ends 4a and 4b of the pin 4. The straight line G that is the center of curvature when machining the belt is set so as to incline forward in the belt traveling direction α and radially inward of the pulley 4 when the pin is engaged with the pulley during U / D. Therefore, by setting the inclination angle at which the straight line G is inclined to be greater than 0 degree and within 15 degrees, the straight line G and the tangential direction L ′ of the pulley 10 between the gear ratio 1.0 and O / D in the normal range. Can be matched. Thereby, the contact area of the pin 4 and the pulley 10 can be maximized, and an advantageous effect in terms of strength of the pin 4 can be obtained.

Further, in a range where the pitch circle radius is smaller than the pitch circle radius where the straight line G and the tangential direction L ′ of the pulley 10 coincide with each other (the transmission ratio is large), the straight line G is inclined forward than the radial direction L of the pulley. The contact position between the pulley 4 and the pulley 10 is also on the front side. Therefore, noise and noise can be reduced. Further, by making the inclination large and setting the straight line G and the tangential direction L ′ of the pulley 10 to coincide with each other at O / D, the pulley 10 is brought into contact with the pulley 10 before the center of the pin 4 in the entire speed ratio. Therefore, the transmission endless belt 1 excellent in quietness can be obtained.
Also in this case, as in the case where the curved surfaces of the both ends 4a and 4b of the pin 4 are curved in the belt traveling direction α, the pin 4 is in contact with the pulley 10 in front of the U / D. Thus, the same effect as when the curved surface is curved in the belt traveling direction α can be obtained.
Other configurations and other functions and effects of the transmission endless belt 1 of this example are the same as those of the above-described example.

  FIG. 7 is a partial view showing a state in which the transmission endless belt of each example described above is caught in the primary pulley during underdrive (U / D), and FIG. 8 is a diagram of each example described above when the gear ratio is 1.0. FIG. 9 is a partial view showing a state in which the transmission endless belt is caught in the primary pulley, and FIG. 9 is a partial view showing a state in which the transmission endless belt in each of the above examples is caught in the primary pulley during overdrive (O / D). . In the following description, the case of the transmission endless belt using the pin of the example shown in FIG. 3 will be described, but the same applies to the case of the transmission endless belt using the pin of the example shown in FIG.

  As shown in FIG. 7, since the pitch circle radius of the primary pulley is small during U / D, as the transmission endless belt 1 is wound around the primary pulley, the straight line S of the pin 4 changes in the radial direction of the primary pulley (shown in the figure). However, it is inclined clockwise from the aforementioned L). Therefore, the pin 4 gradually tilts forward with respect to the belt traveling direction α. This can be understood by the pin 4 coming into contact with the strip 5 on the outer peripheral end side.

  Further, as shown in FIG. 8, when the transmission gear ratio is 1.0, even if the transmission endless belt 1 is wound around the primary pulley, the straight line S of the pin 4 is in the radial direction of the primary pulley (not shown, although not shown above). L). Therefore, the pin 4 is not inclined with respect to the belt traveling direction α. This can be understood by the pin 4 coming into contact with the strip 5 slightly on the inner peripheral side from the radial center of the primary pulley.

  Further, as shown in FIG. 9, since the pitch circle radius of the primary pulley becomes large during O / D, the straight line S of the pin 4 becomes the radius of the primary pulley as the transmission endless belt 1 is wound around the primary pulley. It is inclined counterclockwise from the direction (not shown, L mentioned above). Therefore, the pin 4 gradually tilts backward with respect to the belt traveling direction α. This can be understood by the pin 4 coming into contact with the strip 5 on the inner peripheral end side more than in the case of the gear ratio 1.0.

  In each of the above-described examples, the case where the curved surfaces of both ends 4a and 4b of the pin 4 are bent in the belt traveling direction α or in the direction orthogonal to the belt traveling direction α has been described. The curved surfaces of both ends 4a and 4b can be formed so as to bend in both the belt traveling direction α and the direction orthogonal to the belt traveling direction α. In this case, since the one with a larger radius of curvature has substantially the same action as a flat surface, the one with the smaller radius of curvature can obtain the above-described effect.

  Further, the curvature of the curved surfaces of the ends 4a and 4b of the pin 4 can be constituted by a plurality of curvature radii. In this case, the above-described effect can be obtained when the straight line S or G having the largest radius of curvature satisfies the above-described conditions. In order to increase the contact area between the pin 4 and the pulley 10 and improve the wear durability, the end 4a, 4b of the pin 4 and the pulley 10 are brought into contact with each other at the portion having the largest curvature radius in the same curve. It is because it sets so that it may. For example, the case where the curvature radius for chamfering only the peripheral part of the end surface of the pin 4 is made small can be considered.

The power transmission endless belt of the present invention can be suitably used for a belt type continuously variable transmission of various machines, including a belt type continuously variable transmission for a vehicle such as an automobile.
The belt-type continuously variable transmission of the present invention can be suitably used for various machines using a belt-type continuously variable transmission, including vehicles such as automobiles using the belt-type continuously variable transmission.

It is a partial side view which shows a part of transmission endless belt which concerns on an example of embodiment of this invention. FIG. 2 is a partial plan view showing a part of the transmission endless belt of the example shown in FIG. 1 as viewed from the outer peripheral side. The pin of the endless belt for transmission of the example shown in FIG. 1 is shown, (A) is a front view, (B) is a plan view (top view), and (C) is a left side view. FIG. 1 shows a contact area between a pin and a pulley in the power transmission endless belt shown in FIG. 1, (A) shows a case where the pitch circle radius is small and the pin is tilted forward, and (B) shows that the pin is tilted forward and The figure which shows the case where neither of the back inclination is carried out, (C) is a figure which shows the case where the pitch circle radius is large and the pin is inclined backward. The pin of the endless belt for transmission which concerns on the other example of embodiment of this invention is shown, (A) is a front view, (B) is a top view (top view), (C) is a left view. FIG. 5 shows a contact area between a pin and a pulley in the power transmission endless belt shown in FIG. 5, (A) is a diagram showing a case where the pitch circle radius is small and the pin is tilted forward, and (B) is a diagram where the pin is tilted forward and The figure which shows the case where neither of the back inclination is carried out, (C) is a figure which shows the case where the pitch circle radius is large and the pin is inclined backward. It is a fragmentary figure which shows the state in which the endless belt for transmission is wound in a primary pulley at the time of underdrive (U / D). FIG. 5 is a partial view showing a state where a transmission endless belt is caught in a primary pulley when the speed ratio is 1.0. It is a fragmentary figure which shows the state in which the endless belt for transmission is wound in a primary pulley at the time of overdrive (O / D).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Endless belt 2 for transmission 2 Link plate 3 Joint 4 Pin 4a, 4b Pin 4 end 5 Strip 10 Pulley 10c, 10d Pulley wall surface α of pulley 10 Belt traveling direction S Radius of curvature when bending pin end surface in belt traveling direction Central straight line G Center of curvature radius when bending the end face of the pin in a direction perpendicular to the belt traveling direction

Claims (10)

An endless belt for transmission that is wound around two pulleys and transmits torque between the pulleys, and has a large number of link plates and curved surfaces at both ends as a contact surface with the pulley wall surface, and adjacent link plates are connected to each other. In an endless belt for transmission consisting of a pin that is connected and endless,
The curved surface of the pin end surface is generally curved in the belt traveling direction,
The straight line that becomes the center of curvature when machining the curved surface on the end surface of the pin is the outside in the radial direction of the pulley and the belt traveling direction when the pin is engaged with the pulley during underdrive (U / D). An endless belt for transmission, which is set to incline forward. 2. The transmission endless belt according to claim 1, wherein the straight line is set to coincide with the radial direction of the pulley within a speed ratio of 1.0 to overdrive (O / D). An endless belt for transmission that is wound around two pulleys and transmits torque between the pulleys, and has a large number of link plates and curved surfaces at both ends as a contact surface with the pulley wall surface, and adjacent link plates are connected to each other. In an endless belt for transmission consisting of a pin that is connected and endless,
The curved surface of the pin end surface is curved in a direction substantially perpendicular to the belt traveling direction;
The straight line that becomes the center of curvature when processing the curved surface on the pin end surface is the front side in the belt traveling direction and the radial direction of the pulley when the pin is engaged with the pulley during underdrive (U / D). An endless belt for transmission, which is set to incline inward. 4. The transmission endless belt according to claim 3, wherein the straight line is set to coincide with a tangential direction of the pulley within a speed ratio of 1.0 to overdrive (O / D). An endless belt for transmission that is wound around two pulleys and transmits torque between the pulleys, and has a large number of link plates and curved surfaces at both ends as a contact surface with the pulley wall surface, and adjacent link plates are connected to each other. In an endless belt for transmission consisting of a pin that is connected and endless,
The curved surface of the pin end surface is curved in both the belt traveling direction and the direction substantially perpendicular to the belt traveling direction,
When the radius of curvature that curves in the belt traveling direction is larger than the radius of curvature that curves in the perpendicular direction, a straight line that becomes the center of curvature when machining a curved surface that curves in the belt traveling direction on the pin end surface is , The pin is set to be inclined radially outward of the pulley and forward in the belt traveling direction in a state where the pin is engaged with the pulley during underdrive (U / D),
Further, when the radius of curvature that curves in the perpendicular direction is larger than the radius of curvature that curves in the belt traveling direction, it becomes the center of curvature when machining the curved surface that curves in the perpendicular direction on the pin end surface. The straight line is set so as to incline forward in the belt traveling direction and radially inward of the pulley when the pin is engaged with the pulley during underdrive (U / D). Endless belt. When the radius of curvature that curves in the belt traveling direction is greater than the radius of curvature that curves in the perpendicular direction, the curve that curves in the belt traveling direction within a speed ratio of 1.0 to overdrive (O / D). When the straight line of the surface is set to coincide with the radial direction of the pulley, and the radius of curvature that curves in the perpendicular direction is larger than the radius of curvature that curves in the belt traveling direction, the transmission ratio is from 1.0. 6. The transmission according to claim 5, wherein the straight line of the curved surface curved in the vertical direction within an overdrive (O / D) range is set to coincide with a tangential direction of the pulley. Endless belt. An endless belt for transmission that is wound around two pulleys and transmits torque between the pulleys, and has a large number of link plates and curved surfaces at both ends as a contact surface with the pulley wall surface, and adjacent link plates are connected to each other. In an endless belt for transmission consisting of a pin that is connected and endless,
The curved surface of the pin end surface is generally curved in the belt traveling direction, and the curvature of the curved surface is composed of a plurality of radii of curvature,
When a curved surface having the largest radius of curvature is machined on the pin end surface, the straight line that becomes the center of curvature is radially outward of the pulley when the pin is engaged with the pulley during underdrive (U / D). And an endless belt for transmission, which is set so as to incline forward in the belt traveling direction. An endless belt for transmission that is wound around two pulleys and transmits torque between the pulleys, and has a large number of link plates and curved surfaces at both ends as a contact surface with the pulley wall surface, and adjacent link plates are connected to each other. In an endless belt for transmission consisting of a pin that is connected and endless,
The curved surface of the pin end surface is generally curved in a direction perpendicular to the belt traveling direction, and the curvature of the curved surface is composed of a plurality of curvature radii,
When a curved surface having the largest radius of curvature is machined on the end surface of the pin, the straight line serving as the center of curvature is on the front side in the belt traveling direction when the pin is engaged with the pulley during underdrive (U / D) and An endless belt for transmission, which is set so as to be inclined inward in the radial direction of the pulley. The transmission endless belt according to any one of claims 1 to 8, wherein an inclination angle at which the straight line is inclined is set to be greater than 0 degrees and within 15 degrees. A belt-type continuously variable transmission comprising at least the transmission endless belt according to any one of claims 1 to 9.

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