JP2008180298A - Power transmission chain and power transmission device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power transmission chain having reduced noises and vibration resulting from a change in spaces between a plurality of links arrayed in the cross direction of the chain, and to provide a power transmission device. <P>SOLUTION: A plurality of space holding members 31 are provided for holding the links 11 arrayed in the cross direction of the chain, at both sides in the cross direction of the chain, to keep distances between the outermost side links 11 constant. The space holding members 31 each have a first abutting portion 32 for abutting on the link 11 arrayed in the cross direction of the chain, at one side in the cross direction of the chain, a second abutting portion 33 for abutting it at the other side, and a connection portion 34 for connecting the abutting portions 32, 33 to each other. <P>COPYRIGHT: (C)2008,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. 5, 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) spanned between them, 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 so as to be bendable in the length direction, and are 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 2005-233275 A

  In the power transmission chain of Patent Document 1, noise and vibration may increase when gaps between a plurality of links arranged in the chain width direction change (increase). The gap between the links is secured in the initial state because the pins are press-fitted and fixed to the links. In this case, vibration may increase.

  An object of the present invention is to provide a power transmission chain and a power transmission device that reduce the noise and vibration caused by the change in the distance by paying attention to the distance between a plurality of links arranged in the chain width direction.

  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. One of the first pin and the second pin is fixed to the pin fixing portion provided in the front portion of the front insertion portion of one link and provided in the front portion of the rear insertion portion of the other link. The other side is movably fitted into the pin movable part provided on the rear part of the front insertion part of one link and the other part of the rear insertion part of the other link. Pin fixing on the rear part In the power transmission chain fixed to the chain, it is provided with a plurality of interval holding members that hold the links arranged in the chain width direction from both sides of the chain width direction and keep the distance between the outermost links constant. To do.

  Each pin is fixed to the pin fixing portion of the corresponding link, for example, by press-fitting, whereby the link is positioned in a state where a predetermined gap is provided between the links. That is, the inter-link gap is guaranteed by the initial pressure input. Therefore, if the press-fitting is loosened due to a change in the link shape with time or repeated elastic deformation due to an external force, the size of the gap may change. The change in the size of the gap contributes to an increase in noise, but this is prevented by the spacing member.

  The interval holding members are arranged at predetermined intervals in the chain traveling direction. The spacing member is made of, for example, a thin metal plate, rubber, or synthetic resin, and includes a first contact portion that is applied from one side of the chain width direction to a link that is aligned in the chain width direction, and a first contact portion that is applied from the other side. 2 contact parts and a connection part which connects both contact parts. The distance between the inner surface of the first abutting portion and the inner surface of the second abutting portion is set to be equal to or slightly smaller than the distance between the outermost links, and the spacing member is abutted when the abutting member is attached to the chain. The chain is held by the elastic force of the part and the frictional force between the links. In order to ensure the holding, a convex portion is provided on the inner surface of each abutting portion, and a concave portion is formed on the outer surface of the outermost link so that the convex portion of the spacing member is fitted. Is more preferable.

  For example, the interval holding member may be attached from the outer diameter side of the chain, or may be attached from the inner diameter side of the chain to hold the links aligned in the chain width direction by a pair of interval holding members.

  For example, in a chain, 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 in the traveling direction. A plurality of links may be formed, and the number of links included in each link row may be different. In this case, the spacing member may be provided only in the link row having a large number of links.

  The pin is fixed to the pin fixing portion by, for example, fitting and fixing the inner edge of the pin fixing portion and the outer peripheral surface of the pin by mechanical press-fitting. Alternatively, shrink fitting or cold fitting may be used. The fitting and fixing is preferably performed at the edges (upper and lower edges) of the portion orthogonal to the length direction of the pin fixing portion. After the fitting and fixing, a pre-tension is applied in the pre-tension applying step, so that an appropriate and residual compressive stress is equally applied to the pin fixing portion (pin press-fitting portion) of the link.

  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").

  The link is made of, for example, 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 this specification, one end side in the length direction of the link is front and the other end side is rear, but this front and rear are for convenience, and the length direction of the link always coincides with the front and rear direction. It doesn't mean that.

  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 is composed of 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. Is moved by the hydraulic actuator, the distance between the sheave surfaces of the continuously variable transmission, that is, the wrapping radius of the chain is changed, and the continuously variable transmission can be performed with 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 above.

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

  According to the power transmission chain of the present invention, since the gap maintaining member prevents the gap between the links arranged in the chain width direction from changing, an increase in vibration in the chain width direction due to secular change is suppressed, Noise and vibration can be reduced.

  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) and (13) provided at predetermined intervals in the chain length direction. A plurality of links (11) and a plurality of pins (first pin) (14) and an interpiece (second pin) (15) for connecting the links (11) arranged in the chain width direction so as to be bendable in the length direction And. The interpiece (15) is made shorter than the pin (14), and both are opposed to each other with the interpiece (15) disposed on the front side and the pin (14) disposed on the rear side.

  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.

  As shown in FIG. 2, the pin (14) is wider in the front-rear direction than the interpiece (15), and extends to the pin (14) side at the upper and lower edges of the interpiece (15). Protruding edges (15a) and (15b) are provided. A column part (21) is interposed between the front insertion part (12) and the rear insertion part (13) of the link (11), and the front insertion part (12) of the link (11) It consists of a pin movable part (16) to which (14) is movably fitted and an interpiece fixing part (17) to which the interpiece (15) is fixed, and the pin (14) is fixed to the rear insertion part (13) The pin fixing portion (18) and the interpiece (15) are movably fitted to each other and the interpiece movable portion (19).

  When connecting the links (11) aligned in the chain width direction, the links (11) so that the front insertion part (12) of one link (11) and the rear insertion part (13) of the other link (11) correspond to each other ( 11) are overlapped with each other, the pin (14) is fixed to the rear insertion part (13) of one link (11) and movably fitted to the front insertion part (12) of the other link (11), The interpiece (15) is movably fitted to the rear insertion portion (13) of one link (11) and fixed to the front insertion portion (12) of the other link (11). The pins (14) and the interpiece (15) are relatively rolled and brought into contact with each other, whereby the links (11) can be bent in the length direction (front-rear direction).

  At the boundary between the pin fixing part (18) of the link (11) and the interpiece movable part (19), the upper and lower concave arcuate guide parts (19a) (19b) of the interpiece movable part (19) are connected. Upper and lower convex arc-shaped holding portions (18a) and (18b) for holding the pin (14) fixed to the pin fixing portion (18) are 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.

  In FIG. 1, the plurality of links (11) arranged in the chain width direction are arranged such that a gap of about 0.01 to 0.03 mm is formed between adjacent links (11). While the pin (14) and interpiece (15) are secured to the link (11), the gap between the links (11) adjacent in the width direction is also kept constant, and the noise characteristics change. The pin (14) and the interpiece (15) and the link (11) can be loosened due to aging, which increases noise and vibration.

  Therefore, in the power transmission chain (1) according to the present invention, the links (11) aligned in the chain width direction are held from both sides of the chain width direction, and a plurality of intervals are maintained to keep the distance between the outermost links (11) constant. A member (31) is provided. The interval holding member (31) is provided on both the inner diameter side and the outer diameter side of all the links in the link row having nine links.

  As shown in FIG. 3, the spacing member (31) has a first contact portion (32) applied from one side of the chain width direction to the link (11) arranged in the chain width direction, and a first contact portion (32) applied from the other side. It consists of two contact parts (33) and the connection part (34) which connects both contact parts (32) and (33). A convex portion (35) is provided on the inner surface of each contact portion (32) (33), and the convex portion (35) of the spacing member (31) is provided on the outer surface of the outermost link (11). ) Is formed in the recess (36).

  In FIG. 3, the spacing members (31) are provided on both the upper and lower sides, but may be provided on only one of them. In FIG. 1, the spacing member (31) is provided only in the link row having a large number of links, but may be provided in a link row having a small number of links.

  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.In this embodiment, the contact surface of the pin (14) It has an involute shape having a base circle of radius Rb and center M, and the contact surface of the interpiece (15) is a flat surface (the cross-sectional shape is a straight line). As a result, when each link (11) moves from the straight portion of the chain (1) to the curved portion or from the curved portion to the straight portion, the pin (14) is fixed in the front insertion portion (12). The contact surface of the piece (15) moves in the pin movable part (16) while rolling (including some sliding contact) to the contact surface of the interpiece (15), and in the rear insertion part (13) The interpiece (15) rolls into contact with the contact surface of the pin (14) with respect to the pin (14) fixed in the interpiece movable part (19) (including some sliding contact). Move while. 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.

  This power transmission chain (1) holds the required number of pins (14) and interpieces (15) vertically on the table, and then press-fits one or several links (11) one by one. It is manufactured by going. This press-fitting is performed between the upper and lower edges of the pin (14) and the interpiece (15) and the upper and lower edges of the pin fixing part (18) and the interpiece fixing part (17). It is set to 0.005 mm to 0.1 mm. In this way, tension is applied (pre-tensioned) to the assembled chain (1).

  In the above power transmission chain (1), polygonal vibration is caused by repeated vertical movement of the pin, which causes noise, but the pin (14) and the interpiece (15) are relatively rolled and moved in 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. Further, since the vibration generated by the change in the size of the gap between the links (11) arranged in the chain width direction is prevented by the spacing member (31), further reduction of noise and vibration is achieved.

  The power transmission chain described above is used in the CVT shown in FIG. 5. At this time, as shown in FIG. 4, the fixed sheave (2a) and the movable sheave (2) of the pulley (2) having the pulley shaft (2e). The end surface of the pin (14) is the conical sheave surface (2c) (2d) of the pulley (2) with the end surface of the interpiece (15) not in contact with each conical sheave surface (2c) (2d) of 2b). Power is transmitted by the frictional force generated by this contact. As described above, the pin (14) and the interpiece (15) are guided by the movable parts (16) and (19) to move in rolling contact with each other, so that the sheave surfaces (2c) (2d) of the pulley (2) On the other hand, the pin (14) hardly rotates, the friction loss is reduced, and a high power transmission rate is secured.

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 the link. FIG. 3 is a cross-sectional view showing a main part of the power transmission chain according to the present invention. FIG. 4 is a front view showing a state in which the power transmission chain is attached to the pulley. FIG. 5 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) Link
(12) Front insertion part
(13) Rear insertion part
(14) Pin (1st pin)
(15) Interpiece (2nd pin)
(31) Spacing member
(32) First contact part
(33) Second contact part
(34) Connecting part
(35) Convex
(36) Recess

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 aligned 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. The first pin and the plurality of second pins are provided, and the first pin and the second pin are relatively in rolling contact with each other, whereby the links can be bent in the longitudinal direction. One of the two pins is fixed to a pin fixing portion provided at the front portion of the front insertion portion of one link and is movable to a pin movable portion provided at the front portion of the rear insertion portion of another link The other side is a pin that is movably fitted in a pin movable part provided in the rear part of the front insertion part of one link and provided in the rear part of the rear insertion part of the other link Power transmission chain fixed to the fixed part Oite,
A power transmission chain comprising a plurality of spacing members that hold links arranged in the chain width direction from both sides of the chain width direction and maintain a constant distance between the outermost links.   The interval holding member includes a first contact portion that is applied from one side in the chain width direction to a link arranged in the chain width direction, a second contact portion that is applied from the other side, and a connecting portion that connects the two contact portions. The power transmission chain according to claim 1, wherein a convex portion is provided on an inner surface of each contact portion, and a concave portion into which the convex portion of the spacing member is fitted is formed on the outer surface of the outermost link. .   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 or 2.

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