JP2001227607A - Power transmission ring and variable-diameter pulley using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission ring and a variable-diameter pulley capable of securing desired strength without increasing the number of manufacturing process. SOLUTION: A tapered surface 31a parallel to power transmission surfaces 1a, 2a of sheaves 1, 2 is formed on both side surfaces of a metallic ring 31. A resin ring 32 having a raceway surface 32a on the outside surface is integrated with the tapered surface 31a, whereby the axial wall thickness of the raceway part 32a of the resin ring 32 is made equal extending from the inner peripheral side and the outer peripheral side, and the shrinkage amount after molding can be made uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power transmission ring held between a pair of sheaves and a variable diameter pulley using the same.

[0002]

2. Description of the Related Art Conventionally, as a variable-diameter pulley capable of changing the effective diameter (contact diameter) of a belt wound around a pulley, for example, a tapered power transmission surface 101 is formed as shown in FIG. A pair of sheaves 100 are provided so as to be relatively movable in the axial direction with their power transmission surfaces 101 facing each other, and a power transmission ring 102 around which a belt B is wound around an outer peripheral surface is attached to the pair of power transmission surfaces. 10
1 is provided so as to be held eccentrically with respect to the axis of both sheaves 100 and that one of the sheaves 100 is biased toward the other sheave 100 by a disc spring 103 (for example, Japanese Patent Laid-Open No. No. 30300). In this type of variable diameter pulley, the power transmission ring 102 is formed of a metal such as an aluminum alloy or a synthetic resin, and has a tapered raceway surface that matches the power transmission surface 101 on both side surfaces. 105 is formed.

[0003]

In the conventional variable diameter pulley, torque is transmitted between the power transmission surface 101 of the sheave 100 and the raceway surface 105 of the power transmission ring 102, but the contact area between them is small. Therefore, the surface pressure becomes very high. In addition, the contact between them becomes a complicated state in which rolling contact for transmitting torque and sliding contact when the power transmission ring 102 is eccentric are mixed. For this reason, the metal power transmission ring 102 has a problem that seizure easily occurs between the power transmission ring 102 and the power transmission surface 101. Also,
The power transmission ring 102 made of a synthetic resin has a problem in that the seizure hardly occurs, but is weaker than the metal-made power transmission ring and is easily damaged.

Therefore, as shown in FIG. 9, a power transmission ring 102 made of synthetic resin is attached to a metal ring 10 for reinforcement.
6 may be buried. However, if a metal ring having a rectangular cross section is used as the metal ring 106, the axial thickness a of the resin portion on which the raceway surface 105 is formed is different between the outer circumferential side and the inner circumferential side corresponding to the taper of the raceway surface 105. As a result, the shrinkage ratio of the resin in the resin portion after the molding is different between the inner peripheral side and the outer peripheral side. As a result, the taper angle of the raceway surface 105 greatly varies from one molded product to another. For this reason, it is necessary to finish the raceway surface 105 by cutting after the molding, which causes a new problem that the number of manufacturing steps of the power transmission ring 102 increases. The present invention has been made in view of the above problems, and has as its object to provide a power transmission ring capable of securing a desired strength without increasing the number of manufacturing steps, and a variable diameter pulley using the same. .

[0005]

In order to achieve the above object, a power transmission ring according to the present invention has a power transmission surface formed on each side surface of a pair of sheaves facing each other, so that the power transmission ring is provided at the center of both sheaves. A power transmission ring that is eccentrically clamped and has tapered raceway surfaces that respectively match the power transmission surfaces of the pair of sheaves on both side surfaces, and a power transmission ring around which a belt is wound around the outer peripheral surface. A metal ring having a tapered surface parallel to the raceway surface; a resin ring having the raceway surface on the outer surface and having an annular plane parallel to the raceway surface inside the metal ring; and the metal ring and the resin ring. Are integrated by joining at least the tapered surface and the annular flat surface (claim 1).

A variable diameter pulley according to the present invention comprises: a pair of sheaves provided so as to be relatively movable in the axial direction with power transmission surfaces formed on side surfaces facing each other; A power transmission ring which is eccentrically held with respect to the axis of the shaft, has a tapered raceway surface parallel to the power transmission surface of the pair of sheaves on the side surface, and a belt is wound around the outer peripheral surface, In a variable diameter pulley comprising an elastic member for urging at least one sheave toward the other sheave, the power transmission ring has a metal ring having a tapered surface parallel to the raceway surface on both side surfaces,
A resin ring having the raceway surface on the outer side surface and having an annular plane parallel to the raceway surface inside the raceway surface,
The metal ring and the resin ring are integrated by joining at least the tapered surface and the annular flat surface.

According to the power transmission ring and the variable-diameter pulley of the above construction, the raceway surface of the resin ring and the annular flat surface which is the joining surface to the metal ring inside the resin ring are parallel. The axial thickness of the formed portion can be made uniform from the inner peripheral side to the outer peripheral side. For this reason, the amount of shrinkage of the portion after molding can be made uniform, and variation in the taper angle of the raceway surface can be suppressed.

[0008]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG.
1 is a sectional view showing a variable diameter pulley according to an embodiment of the present invention. The variable diameter pulley is used as a driven pulley for driving accessories such as an alternator provided in an automobile engine, for example, and is concentrically opposed to a rotating shaft S as a driven shaft. A belt (V-rib belt) B is wound around the first sheave 1 and the second sheave 2 provided in a state and an outer peripheral surface, and a power transmission ring 3 held between the pair of sheaves 1 and 2.
A main part is constituted by a disc spring 4 as an elastic member for urging the sheaves 1 and 2 toward each other, and a spring retainer 5 for receiving the disc spring 4.

The first sheave 1 has a circular annular main body 11.
A cylindrical boss 12 on the inner peripheral side and an annular rim 13 on the outer peripheral side.
Are formed respectively. The boss 12 extends to the back surface of the second sheave 2 in parallel with the axis of the rotation axis S, and the rim 13 projects outside the main body 11. A tapered power transmission surface 1a as a torque transmission surface is formed on a side surface of the main body 11 facing the second sheave 2, and one side surface of the power transmission ring 3 is formed on the power transmission surface 1a. In contact. The boss 12 is axially slidably fitted to a sleeve 51 of the spring retainer 5 via a bush 14 as a slide bearing.
Further, the rim 13 is provided with a plurality of concave portions 15 which are fitted on the outer peripheral side of one of the disc springs 4 at equal circumferential intervals (see FIG. 2).

The second sheave 2 has a substantially symmetrical shape with respect to the first sheave 1, and has a cylindrical boss 22 on the inner peripheral side of a circular annular main body 21 and an annular rim 23 on the outer peripheral side. Each is formed. The boss 22 extends parallel to the axis of the rotation shaft S, and the rim 23 projects outside the main body 21. A tapered power transmission surface 2 a as a torque transmission surface is formed on a side surface of the main body portion 21 facing the first sheave 1. The power transmission surface 2a has a tapered surface opposite to the power transmission surface 1a of the first sheave 1 so as to form a V-shaped annular space with the power transmission surface 1a of the first sheave 1. The other side surface of the power transmission ring 3 is in contact with the power transmission surface 2a. The boss 22 is axially slidably fitted to the boss 12 of the first sheave 1 via a bush 24 as a slide bearing. Further, the rim 23 is provided with a plurality of concave portions 25 which are fitted on the outer peripheral side of the other disc spring 4 at equal circumferential intervals (see FIG. 2).

Referring also to FIG. 3, the power transmission ring 3 includes a metal ring 31 and a resin ring 32 integrated on both side surfaces and an outer peripheral surface of the metal ring 31. The metal ring 31 is made of an aluminum alloy, and a resin ring 32 is integrated with its inner peripheral side exposed. Power transmission surfaces 1a, 2 of the first and second sheaves 1, 2 are provided on both side surfaces of the metal ring 31, respectively.
A tapered surface 31a parallel to a is formed.

The resin ring 32 has a ring shape in which a belt winding portion 32a is formed on the outer peripheral side and a raceway portion 32b is formed on the inner peripheral side. A plurality of V-grooves 32 c for introducing ribs on the peripheral surface are formed, and the inner periphery is joined to the outer periphery of the metal ring 31. A track surface 32 is provided on the outer surface of the track portion 32b.
As for d, an annular flat surface 32e is formed on the inner surface, and this annular flat surface 32e is joined to the tapered surface 31a of the metal ring 31. The raceway surface 32d is a tapered surface parallel to the power transmission surfaces 1a and 2a of the sheaves 1 and 2, and the annular flat surface 32e is a tapered surface parallel to the raceway surface 32d. Therefore, the raceway surface 32d, the annular plane 3
2e and the tapered surface 31a of the metal ring 31 are parallel to each other, and the axial thickness t of the track portion 32b is the same from the outer peripheral side to the inner peripheral side. As the material of the resin ring 32, for example, a material obtained by blending carbon fiber, aromatic polyamide fiber and graphite with phenol resin is excellent in strength and abrasion resistance, and has aggressiveness to the power transmission surfaces 1a and 2a. It is preferable because it is small. In addition, the metal ring 31 and the resin ring 32
It is integrated at the same time as the molding of the resin ring 32 by insert molding.

The disc springs 4 are provided one by one on the left and right, with a plurality of superposed sheets as one set. This disc spring 4
As shown in FIG. 4 and FIG. 5, a plurality of convex portions 41 that match the concave portions 15 and 25 of
Are formed, and a plurality of slits 42 are formed from the inner circumference to the middle.
Are formed radially. Each disc spring 4 is provided with the projection 41
Are fitted in the concave portions 15 and 25 of the sheaves 1 and 2 and the slit 42 is fitted in a convex portion 53 of the spring retainer 5 and elastically deformed by a predetermined amount.
2 and the spring retainer 5, whereby the sheaves 1 and 2 are pressed and biased in a direction approaching each other.

The spring retainer 5 comprises a sleeve 51 in which the first sheave 1 is fitted, and a pair of disk-like retaining plates 52 provided at both ends of the sleeve 51, respectively. The plate 52 is disposed on the back side of each of the sheaves 1 and 2. One holding plate 52 is formed integrally with the sleeve 51, and the other holding plate 52 is bolted to an end of the sleeve 51. further,
The slit 4 of the disc spring 4 is provided on the outer peripheral side of the holding plate 52.
2 are provided on the circumference equally. The sleeve 51 is fitted to the rotary shaft S using a key 54 so as to be integrally rotatable so that torque can be transmitted to the rotary shaft S of the accessories.

The variable diameter pulley can transmit the driving force of the belt B to the rotating shaft S via the power transmission ring 3, the sheaves 1 and 2, the disc spring 4, and the spring retainer 5.
At this time, the rotation speed of the rotation shaft S can be automatically adjusted according to the tension of the belt B. For example, when the tension of the belt B is increased by a tension adjusting mechanism (not shown), the power transmission ring 3 moves the sheaves 1 and 2 away from each other while separating the sheaves 1 and 2 from each other against the urging force of the disc spring 4. Eccentric (see FIG. 6). Thereby, the effective diameter of the belt B wound around the power transmission ring 3 is reduced,
The speed increase ratio increases. When the tension of the belt B becomes equal to or less than a predetermined value from this state, the sheaves 1 and 2 approach each other due to the urging force of the disc spring 4, and finally the power transmission ring 3 is concentric with the sheaves 1 and 2. State (see FIG. 1). As a result, the effective diameter of the belt B wound around the power transmission ring 3 increases, and the speed increase ratio decreases.

In the variable diameter pulley having the above configuration, the axial thickness t of the raceway portion 32b of the resin ring 32 is the same from the outer peripheral side to the inner peripheral side. The amount can be made uniform, and the accuracy of the taper angle of the raceway surface 32d can be reliably ensured only by resin molding. Therefore, it is not necessary to finish the raceway surface 32d by cutting, and the manufacturing process of the power transmission ring 3 can be simplified accordingly.

As shown in FIG. 7, the power transmission ring 3 includes a belt winding portion 32a formed on a resin ring 32,
It may be formed on the metal ring 31 side. In short, the resin ring 32 only needs to have at least the track portion 32b. Further, the variable diameter pulley of the present invention may be configured such that only one of the sheaves 1 and 2 is urged by the disc spring 4 and the metal ring 31 of the power transmission ring 3 is completely covered by the resin ring 32. Design changes can be made.

[0018]

As described above, according to the power transmission ring and the variable pulley of the present invention, the axial thickness of the resin ring where the raceway surface is formed is the same from the inner circumference to the outer circumference. Yes, since the shrinkage of the portion after molding can be made uniform, the accuracy of the taper angle of the raceway surface can be favorably secured by resin molding, and the finishing process of the raceway surface can be omitted. . Therefore, although the strength of the power transmission ring can be reinforced by the metal ring, it is possible to prevent an increase in the number of manufacturing steps.

[Brief description of the drawings]

FIG. 1 is a sectional view of a variable diameter pulley according to an embodiment of the present invention.

FIG. 2 is a side view of a sheave.

FIG. 3 is an enlarged sectional view of a main part of a power transmission ring.

FIG. 4 is a side view of the disc spring.

FIG. 5 is a sectional view of a disc spring.

FIG. 6 is a cross-sectional view of the variable diameter pulley showing a state where the power transmission ring is eccentric.

FIG. 7 is a sectional view of a main part showing another embodiment of the power transmission ring.

FIG. 8 is a sectional view showing a conventional variable diameter pulley.

FIG. 9 is a sectional view of a main part showing a power transmission ring in which a metal ring is embedded.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheave 1a Power transmission surface 2 Sheave 2a Power transmission surface 3 Power transmission ring 31 Metal ring 31a Tapered surface 32 Resin ring 32d Track surface 32e Annular plane B belt S Rotating shaft

Claims (2)

[Claims] A power transmission surface formed on each side of a pair of sheaves opposed to each other is sandwiched eccentrically with respect to the axis of both sheaves, and the power of the pair of sheaves is provided on both side surfaces. A power transmission ring having a tapered raceway surface corresponding to each transmission surface, and a belt wound around an outer peripheral surface; a metal ring having tapered surfaces parallel to the raceway surface on both side surfaces; And a resin ring having an annular plane parallel to the raceway surface inside the metal ring. The metal ring and the resin ring are integrated by joining at least the tapered surface and the annular plane. A power transmission ring, characterized in that: 2. A pair of sheaves provided so as to be relatively movable in the axial direction with power transmission surfaces formed on side surfaces facing each other, and eccentric with respect to the axis of both sheaves by the power transmission surfaces. And a power transmission ring having a tapered track surface parallel to the power transmission surfaces of the pair of sheaves on the side surface, and a belt wound around the outer peripheral surface, and at least one of the sheaves being the other. A variable diameter pulley comprising an elastic member biasing to a sheave side, wherein the power transmission ring has a metal ring having a tapered surface parallel to the raceway surface on both side surfaces, and the raceway surface on an outer side surface, A resin ring having an annular plane parallel to the raceway surface is provided inside, and the metal ring and the resin ring are integrated by joining at least the tapered surface and the annular plane. Variable diameter pulleys characterized.