JP2009079639A - Power transmission chain and power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmission chain which does not deteriorate durability even if a pitch is narrowed, and a power transmission device. <P>SOLUTION: In one type among a plurality of links 11, 31, the front surface L1 of the link 31 is formed in parallel to the front surface L2 of a front insertion part 12, and the rear surface L3 of the link 31 is formed in parallel to the rear surface L5 of a rear insertion part 33. The link 31 is combined with a link in which the front surface of the link 11 is formed in parallel to the front surface of the front insertion part, while the rear surface of the link 11 is formed in non-parallel to the rear surface of the rear insertion part, and arrayed at random. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a power transmission chain, and more particularly to a power transmission chain and a power transmission device suitable for a continuously variable transmission (CVT) of a vehicle such as an automobile.

  As a continuously variable transmission for an automobile, as shown in FIG. 6, a drive pulley (2) provided on the engine side having a fixed sheave (2a) and a movable sheave (2b), a fixed sheave (3b) and a movable sheave (3a) and a driven pulley (3) provided on the drive wheel side and an endless power transmission chain (1) bridged between the two, and a movable sheave (2b) (3a) by a hydraulic actuator The chain (1) is clamped with hydraulic pressure by moving it toward and away from the fixed sheave (2a) (3b), and this clamping force makes contact between the pulley (2) (3) and the chain (1). It is known that a load is generated and torque is transmitted by the frictional force of the contact portion.

As a power transmission chain, in Patent Document 1, a plurality of links having front and rear insertion portions through which pins are inserted, a front insertion portion of one link, and a rear insertion portion of another link correspond to the chain width direction. A plurality of first pins and a plurality of second pins that connect the links arranged in a row in a longitudinal direction so as to be fixed to the front insertion portion of one link and movable to the rear insertion portion of another link The first pin that is fitted and the second pin that is movably fitted to the front insertion portion of one link and fixed to the rear insertion portion of the other link are relatively rolled and moved in contact with each other. Those that can be bent in the length direction have been proposed.
JP 2006-97844 A

  According to the power transmission chain of Patent Document 1 described above, the link having a large pitch with respect to the reference link has an increased strength and is advantageous for durability. However, when the pitch is reduced, the front / rear insertion is performed. Since the size of the part is maintained and the link is made small, there is a concern that the durability of the link is lowered.

  An object of the present invention is to provide a power transmission chain and a power transmission device that do not reduce durability even when the pitch is reduced.

  The power transmission chain according to the present invention includes a plurality of links having front and rear insertion portions through which pins are inserted, and links arranged in the chain width direction so that a front insertion portion of one link and a rear insertion portion of another link correspond to each other. A plurality of first pins and a plurality of second pins arranged before and after connecting each other are provided, and the first pin and the second pin are relatively rolled and brought into contact with each other, whereby the links can be bent in the length direction. In at least one of the plurality of links, the front surface of the link and the front surface of the front insertion portion are parallel to each other, and the rear surface of the link and the rear surface of the rear insertion portion are parallel to each other. It is characterized by being.

  The conventional link is an inclined link in which the front surface of the link and the front surface of the front insertion portion are parallel, and the rear surface of the link and the rear surface of the rear insertion portion are not parallel. The rear surface of the rear insertion portion of the inclined link is inclined by the angle of attack θ with respect to the rear surface of the link. In order to make the inclined link into a parallel link, it is only necessary to form the rear surface of the rear insertion portion parallel to the rear surface of the link, but in this case, in other words, so as not to reduce the longitudinal dimension of the rear column portion, The parallel plane is set so that the size of the rear insertion portion is reduced.

  In the power transmission chain according to the present invention, at least one of the first pin and the second pin comes into contact with the pulley to transmit power by frictional force. In a chain in which one of the pins contacts the pulley, one of the first pin and the second pin is a pin that contacts the pulley when the chain is used in a continuously variable transmission ( In the following, the pin is referred to as “first pin” or “pin”, and the other is referred to as the pin that does not contact the pulley (interpiece or strip). "Peace").

  Since the pin shape and the link insertion portion shape correspond to each other, the rear surface of the pin inserted through the parallel link is parallel to the rear surface of the link. The pin inserted through the inclined link has a predetermined angle of attack, which corresponds to a conventional pin.

  The angle of attack is an angle formed by a plane perpendicular to the chain traveling direction and the back surface of the pin (the surface opposite to the rolling contact surface), and with respect to the pin that contacts the pulley (ie, the first pin or the pin) It is set to a predetermined value. The pin has a predetermined angle of attack and has an inclined linear portion corresponding to the inclined link (the same as the conventional one), and the rear surface is cut so that it is parallel to the rear surface of the link to correspond to the parallel link. Those having parallel straight portions (thin walls) are used.

  In the random arrangement, parallel links and inclined links are randomly arranged, and pins having parallel straight portions or pins having inclined straight portions are arranged corresponding to the link shape. As described above, the pin having the parallel straight portion is thin and can be inserted not only into the parallel link but also into the inclined link.

  Of course, the above random arrangement may be combined with two types of random link arrangements, the pitch length of the link being random. However, the pitch randomness reduces the column width when the pitch is reduced, resulting in durability. Since there is a fear of falling, links with the same pitch length (parallel links) are created by changing the straight line portion in a direction that is advantageous for durability, based on links (inclined links) with a predetermined column width secured. It is more preferable not to employ random pitch by arranging the inclined links and the parallel links in random order.

  In other words, when the pitch of the inclined link is reduced, the column width is reduced, but when the parallel link is used, the durability can be improved by eliminating the narrow part (weak part), so the pitch is reduced. At the same time, the use of parallel links prevents a decrease in durability. Therefore, if parallel links are created with the same pitch length with respect to the reference inclined link, durability can be improved and a random arrangement that is advantageous for noise reduction can be obtained.

  For configurations other than the link shape, for example, the rolling contact surface shape of the first pin and the second pin, the locus of the contact position between the first pin and the second pin is an involute curve, and the basic circle radius of the involute is assumed to be two levels. In addition, in addition to this, there are two types of end face shapes of the pins that contact the pulley, and the positions that contact the pulley may be two levels. Moreover, you may combine with the thing which arranges the length difference of a pin at random. When adopting a random arrangement of the basic circle radius of the involute, each pin may be provided with a parallel straight portion and an inclined straight portion. A pin having one involute curvature is a parallel straight portion and the other involute. About the pin which has a curvature, it is good also as an inclination straight line part. In the former case, the noise reduction effect is improved by obtaining many types of random arrays, and in the latter case, the problem that it is difficult to identify pin shapes with different involute curvatures is solved.

  In the power transmission chain according to the present invention, the pin is fixed to the front and rear insertion portions of the link by fitting and fixing between the inner edge of the insertion portion and the outer peripheral surface of the pin by mechanical press-fitting, and one insertion portion includes the first pin and the first pin. The two pins are fitted together so as to oppose each other in the length direction of the chain, and either one of them is press-fitted into the peripheral surface of the insertion portion of the link.

  For example, the link is made of spring steel or carbon tool steel. The material of the link is not limited to spring steel or carbon tool steel, and may of course be other steel such as bearing steel. In the link, the front and rear insertion portions may be independent through holes (links with columns), and the front and rear insertion portions may be one through holes (links without columns). Appropriate steel such as bearing steel is used as the material of the pin.

  For example, the first pin and the second pin are formed as involute curved surfaces in which either one of the contact surfaces is a flat surface and the other contact surface is relatively rollable and movable. Moreover, you may make it each contact surface form a required curved surface for the 1st pin and the 2nd pin.

  In the above power transmission chain, one of the pins (interpiece) is shorter than the other pin (pin), the end surface of the longer pin contacts the conical sheave surface of the pulley of the continuously variable transmission, It is preferable that power is transmitted by the frictional force due to this contact. Each pulley includes a fixed sheave having a conical sheave surface and a movable sheave having a conical sheave surface facing the sheave surface of the fixed sheave. The chain is sandwiched between the sheave surfaces of both sheaves, and the movable sheave. Is moved by a hydraulic actuator, the distance between sheave surfaces of the continuously variable transmission, that is, the wrapping radius of the chain is changed, and a continuously variable transmission can be performed with a smooth movement.

  The power transmission device according to the present invention includes a first pulley having a conical sheave surface, a second pulley having a conical sheave surface, and power transmission spanned between the first and second pulleys. And a power transmission chain as described in any of the above.

  This power transmission device is suitable for use as a continuously variable transmission (CVT) of a vehicle such as an automobile.

  According to the power transmission chain of the present invention, if the link front surface and the front insertion portion front surface are parallel and the link rear surface and the rear insertion portion rear surface are parallel links, durability can be improved. By making the link in this way simultaneously with the pitch reduction, even if the pitch is reduced, it is not necessary to reduce the durability. In addition, if the link rear surface and the rear surface of the rear insertion part are made parallel to each other with the same pitch length for the link where the rear surface of the link and the rear surface of the rear insertion part are not parallel, durability is improved. In addition, noise can be reduced by using these links as a random array.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the top and bottom refer to the top and bottom of FIG.

  FIG. 1 shows a part of a power transmission chain according to the present invention. The power transmission chain (1) has front and rear insertion portions (12), (13), (33) provided at predetermined intervals in the chain length direction. ) And a plurality of pins (first pins) (14) (34) for connecting the links (11) (31) arranged in the chain width direction so that they can be bent in the length direction. ) And an interpiece (second pin) (15). The interpiece (15) is made shorter than the pins (14) and (34), and they are opposed to each other with the interpiece (15) disposed on the front side and the pins (14) and (34) disposed on the rear side. ing.

  In the chain (1), three link rows composed of a plurality of links having the same phase in the width direction are arranged in the traveling direction (front-rear direction) to form one link unit, and the link unit composed of the three rows of link rows is the traveling direction. Are connected to each other. In this embodiment, one link unit includes a link row having nine links and two link rows having eight links.

  In the power transmission chain of the present invention, in addition to the combination of the link (11), the pin (14) and the interpiece (15) shown in FIG. 2, the link (31), the pin (34) and the interface shown in FIG. A combination of pieces (15) is used. The link (11) shown in FIG. 2 and the link (31) shown in FIG. 3 have different shapes of the rear insertion portions (13) and (33) as described later.

  As shown in FIGS. 2 and 3, the pins (14) and (34) are wider in the front-rear direction than the interpiece (15). Protruding edges (15a) and (15b) extending toward the pins (14) and (34) are provided on the upper and lower edges of the interpiece (15).

  Each link (11) (31) has a front column part (20) for forming the front surface shape of the front insertion part (12) and a rear surface part for forming the rear surface shape of the rear insertion parts (13) (33). It has a side pillar part (22) (32) and an intermediate pillar part (21) between the front insertion part (12) and the rear insertion part (13) (33). The front insertion part (12) of each link (11) (31) has a pin movable part (16) to which the pins (14) and (34) are movably fitted and an interpiece fixing to which the interpiece (15) is fixed. Part (17), and the rear insertion part (13) (33) is fitted so that the pin fixing part (18) (38) to which the pin (14) (34) is fixed and the interpiece (15) can be moved Interpiece movable part (19).

  When connecting the links (11) (31) arranged in the chain width direction, the front insertion part (12) of one link (11) (31) and the rear insertion part (13) of the other links (11) (31) ) (33) are linked to each other so that the links (11) and (31) are overlapped, the pins (14) and (34) are fixed to the front insertion part (12) of one link (11), and the other links (11) (31) is movably fitted to the rear insertion part (13) (33), and the interpiece (15) is movable to the front insertion part (12) of one link (11) (31) It is fitted and fixed to the rear insertion portions (13) and (33) of the other links (11) and (31). The pins (14) (34) and the interpiece (15) are relatively in rolling contact with each other so that the links (11) (31) can be bent in the length direction (front-rear direction). Is done.

  At the boundary between the pin fixing portions (18) (38) of the links (11) (31) and the interpiece movable portion (19), the upper and lower concave arcuate guide portions (19a) of the interpiece movable portion (19) The upper and lower convex arc-shaped holding portions (18a) (18b) (38a) (38b) that hold the pins (14) (34) that are connected to the pin fixing portions (18) and (38), respectively. Is provided. Similarly, at the boundary between the interpiece fixing part (17) and the pin movable part (16), the upper and lower concave arcuate guide parts (16a) and (16b) of the pin movable part (16) are connected to the interpiece fixed part. Upper and lower convex arc-shaped holding portions (17a) and (17b) for holding the interpiece (15) fixed to the portion (17) are provided.

The locus of the contact position between the pin (14) (34) and the interpiece (15) with respect to the pin (14) (34) is an involute of a circle, and in this embodiment, the pin (14) ( The contact surface 34) has an involute shape having a base circle with a radius Rb and a center M in the cross section, and the contact surface of the interpiece (15) is a flat surface (the cross-sectional shape is a straight line). Thereby, when each link (11) (31) moves from the straight part of the chain (1) to the arc part or from the arc part to the straight part, in the front insertion part (12),
The movable part of the pin (14, 34) while the rolling contact surface of the interpiece (15) with the pin (14) (34) is in contact with the rolling contact surface of the interpiece (15) (including some sliding contact) 16) In the rear insertion part (13) (33), the interpiece (15) is in rolling contact with the pin (14) (34) fixed in the interpiece movable part (19). The surface moves while rolling (including some sliding contact) on the rolling contact surface of the pin (14). In FIG. 2, the portions indicated by reference signs A and B are lines (points in the cross section) where the pin (14) and the interpiece (15) are in contact with each other at the straight portion of the chain (1). Is the pitch.

  In FIG. 3, the interpiece (15) is the same as that of FIG. 2, and the link (31) and the pin (34) have different shapes from those of FIG. The link (11) shown in FIG. 2 has a straight portion L1 provided on the front surface of the link (11) and the front surface of the front insertion portion (12) = the front surface L2 of the interpiece (15) and the link (11 The rear surface of the rear insertion portion (13) = the rear surface L4 of the pin (14) is inclined with respect to the linear portion L3 provided on the rear surface by an angle of attack θ. On the other hand, in the link (31) shown in FIG. 3, the straight portion L1 provided on the front surface of the link (31) and the front surface of the front insertion portion (12) = the front surface L2 of the interpiece (15) are parallel ( This is the same as that in FIG. 2) and the rear surface of the rear insertion portion (33) with respect to the straight portion L3 (also the same as that in FIG. 2) provided on the rear surface of the link (11) = pin (34) The rear surface L5 is a parallel link. The column portion (32) of the parallel link (31) in FIG. 3 is advantageous in terms of durability compared to the column portion (22) of the inclined link (11) in FIG. 2 because L3 and L5 are parallel. It has become.

  Since the shapes of the pins (14) and (34) correspond to the shapes of the insertion portions (12), (13) and (33) of the links (11) and (31), they are inserted into the parallel link (31) of FIG. The straight portion (34a) L5 provided on the rear surface of the pin (34) is parallel to the straight portion L3 provided on the rear surface of the link (11). The pin (14) inserted through the inclined link (11) in FIG. 2 has a straight portion (14a) inclined at a predetermined angle of attack θ, which corresponds to a conventional pin. The angle of attack is the angle between the plane perpendicular to the chain travel direction and the back surface of the pin (14) (34) (the surface opposite to the rolling contact surface), and the pin (14) that contacts the pulley (2) (3) ) (24) is set to a predetermined value.

  The link (11) in FIG. 2 and the link (31) in FIG. 3 have the same pitch (distance between AB). As a result, the pitch of the links (11) and (31) is fixed and the pin (14 The straight portion (14a) L4 of the link (11) is inclined with respect to the surface perpendicular to the chain traveling direction, and the straight portion (34a) L5 of the pin (34) is perpendicular to the surface perpendicular to the chain traveling direction. Parallel links (31) can be randomly arranged. A part of this random arrangement is shown in FIG.

  In FIG. 4, from the left, the inclined link (11) having the inclined pin (14) inserted in the rear insertion portion (13) and the parallel pin (34) inserted in the front insertion portion (12), the rear insertion portion (13). A parallel pin (34), an inclined pin (14) inserted in the front insertion part (12) and a rear part superimposed on the front part of the inclined link (11), a rear insertion part (13) 5 shows an inclined pin (14), and a tilted link (11) in which a parallel pin (34) is inserted into the front insertion part (12) and the rear part is superimposed on the front part of the parallel link (31). Of the two parallel pins (34) shown in the figure, the left parallel pin (34) is inserted through the parallel link (31), and the right parallel pin (34) is fitted into the inclined link (11). The link (11) (31) and the pins (14) (34) are randomly arranged, so that they can be used with inclined links (11) and their durability. The peak of the sound pressure level is reduced without lowering the sound pressure.

  In the above power transmission chain (1), polygonal motion occurs due to repeated up and down movement of the pin, which causes noise, but the pin (14) and the interpiece (15) move relatively in rolling contact. In addition, since the locus of the contact position between the pin (14) and the interpiece (15) with respect to the pin (14) is an involute of the circle, both the contact surfaces of the pin and the interpiece are arcuate surfaces. Compared to the case, vibration can be reduced and noise can be reduced.

  The power transmission chain (1) is used in the V-type pulley type CVT shown in FIG. 6, and at this time, as shown in FIG. 5, the fixed sheave (2a) of the pulley (2) having the pulley shaft (2e) is used. ) And the conical sheave surface (2c) (2d) of the movable sheave (2b) and the end face of the drive pin (14) is the cone of the pulley (2) without the end face of the interpiece (15) (25) contacting Power is transmitted by the frictional force caused by the contact with the sheave surfaces (2c) and (2d).

  When the movable sheave (2b) of the drive pulley (2) at the position indicated by the solid line is moved closer to or away from the fixed sheave (2a), the winding diameter of the drive pulley (2) is indicated by a chain line in the figure. Thus, it is large when approaching and small when separating. Although not shown in the drawing of the driven pulley (3), when the movable sheave moves in the opposite direction to the movable sheave (2b) of the drive pulley (2) and the winding diameter of the drive pulley (2) increases, the driven pulley (2) When the winding diameter of (3) decreases and the winding diameter of the drive pulley (2) decreases, the winding diameter of the driven pulley (3) increases. As a result, on the basis of the state where the gear ratio is 1: 1 (initial value), the winding diameter of the drive pulley (2) is minimum and the winding diameter of the driven pulley (3) is maximum U / D. An (underdrive) state is obtained, and an O / D (overdrive) state in which the winding diameter of the drive pulley (2) is maximum and the winding diameter of the driven pulley (3) is minimum is obtained.

FIG. 1 is a plan view showing a part of one embodiment of a power transmission chain according to the present invention. FIG. 2 is an enlarged side view of a reference shape (inclined shape) link, a reference shape (inclined shape) pin, and an interpiece. FIG. 3 is an enlarged side view of parallel-shaped links, parallel-shaped pins and interpieces. FIG. 4 is a diagram illustrating an example of a random sequence obtained using the combination of FIGS. 2 and 3. FIG. 5 is a front view showing a state in which the power transmission chain is attached to the pulley. FIG. 6 is a perspective view showing a continuously variable transmission.

Explanation of symbols

(1) Power transmission chain
(2) (3) Pulley
(2a) (3b) Fixed sheave
(2b) (3a) Movable sheave
(2c) (2d) Conical sheave surface
(11) Inclined link
(12) Front insertion part
(13) Rear insertion part
(14) Parallel pin (first pin)
(15) Interpiece (2nd pin)
(31) Parallel link
(33) Rear insertion part
(34) Inclined pin (first pin)

Claims (3)

A plurality of links having front and rear insertion portions through which pins are inserted, and a plurality of links arranged before and after connecting links arranged in the chain width direction so that a front insertion portion of one link and a rear insertion portion of another link correspond to each other. In the power transmission chain provided with the first pin and the plurality of second pins, the first pin and the second pin are in rolling contact with each other, whereby the links can be bent in the length direction.
At least one type of the plurality of links is characterized in that the front surface of the link and the front surface of the front insertion portion are parallel, and the rear surface of the link and the rear surface of the rear insertion portion are parallel. Transmission chain.   The multiple links include a link in which the front surface of the link and the front surface of the front insertion portion are parallel, the rear surface of the link and the rear surface of the rear insertion portion are parallel, and the front surface of the link and the front surface of the front insertion portion are parallel and the link. 2. The power transmission chain according to claim 1, wherein the rear surface and the rear surface of the rear insertion portion include links that are not parallel, and these links are randomly arranged.   A power transmission chain comprising: a first pulley having a conical surface sheave surface; a second pulley having a conical surface sheave surface; and a power transmission chain spanned between the first and second pulleys. The power transmission device according to claim 1.

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