JPH10184853A - Roller clutch built-in type pulley - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily install a roller clutch built-in type pulley in a limited space, by superposing the support bearings and the roller clutch in the radial direction, for reducing a size in the axial direction. SOLUTION: A sleeve 2 comprises the coaxial first inner diameter side and first outer diameter side cylinders 7, 8, and the first ring part 9, and the first inner diameter side cylinder 7 is externally fitted to a rotary shaft 6. Further a pully 3 comprises the coaxial second inner diameter side and second outer diameter side cylinders 10, 11, and the second ring part 12, and is installed coaxially with the sleeve 2. The support bearings 4, 4 are interposed between the outer peripheral face of the first inner diameter side cylinder 7 and an inner peripheral face of the second inner diameter side cylinder 10. On this occasion, the inner ring 13 of the support bearings 4, 4 are externally fitted to the outer peripheral face of the first inner diameter side cylinder 7, the outer rings 14 are internally fitted to the inner peripheral face of the second inner diameter side cylinder 10, and the roll clutch 5 is installed on a peripheral part of the support bearings 4, 4 between the inner peripheral face of the first outer diameter side cylinder 8 and the outer peripheral face of the second inner diameter side cylinder 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A pulley with a built-in roller clutch according to the present invention is, for example, a drive pulley fixed to an end of a rotating shaft of an alternator, which is a kind of auxiliary equipment for various engines, and fixed to an end of a crankshaft of the engine. It is used to drive the alternator by wrapping a belt between it and.

[0002]

2. Description of the Related Art An engine accessory such as an alternator is driven by, for example, a belt partially extending over a drive pulley fixed to an end of a crankshaft of a drive engine of an automobile. That is, an endless belt is stretched between the driven pulley fixed to the end of the rotating shaft of the engine accessory and the drive pulley, and the engine accessory is rotatably driven in synchronization with the drive engine. .

Conventionally, as the driven pulley, a pulley simply fixed to the rotary shaft has conventionally been used. On the other hand, in recent years, when the running speed of the belt is constant or increasing, the power can be freely transmitted from the belt to the rotating shaft, and when the running speed of the belt is decreasing, the pulley and the rotating shaft are rotated. Various types of pulleys with a built-in roller clutch that can freely rotate relative to a shaft have been proposed and used in some. For example, JP-A-7-31807-8, JP-A-8-61443, JP-B-7-72585,
French Patent Publication FR226059A1 and the like describe a pulley with a built-in roller clutch having the above functions.

[0004] The pulleys with a built-in roller clutch described in each of these documents have a sleeve that can be externally fitted and fixed to a rotating shaft. A pulley having a cylindrical inner peripheral surface is arranged around the sleeve concentrically with the sleeve. A pair of support bearings and a roller clutch are provided between the outer peripheral surface of the sleeve and the inner peripheral surface of the pulley. Among these, the support bearing allows the sleeve and the pulley to rotate relative to each other while supporting the radial load applied to the pulley. Also, the roller clutch allows the transmission of the rotational force from the pulley to the sleeve only when the pulley rotates in a predetermined direction with respect to the sleeve.

The reason for using such a roller clutch built-in pulley is as follows. For example, when the driving engine is a diesel engine, the rotation angular speed of the crankshaft greatly fluctuates during low rotation, such as during idling. As a result, the running speed of the endless belt stretched over the driving pulley also fluctuates finely.
On the other hand, the rotating shaft of the alternator driven to rotate by the endless belt via the driven pulley does not fluctuate so rapidly due to the inertial mass of the rotating shaft and the rotor fixed to the rotating shaft. Therefore, when the driven pulley is simply fixed to the rotating shaft, the endless belt and the driven pulley tend to rub in both directions due to the fluctuation of the rotational angular velocity of the crankshaft. As a result, stresses in different directions are repeatedly applied to the endless belt that rubs against the driven pulley, so that slipping easily occurs between the endless belt and the driven pulley, or the life of the endless belt is shortened. Or cause

Accordingly, by using the above-mentioned roller clutch built-in type pulley as such a driven pulley, when the running speed of the endless belt is constant or tends to increase, the rotation from the driven pulley to the rotating shaft is performed. When the traveling speed of the endless belt tends to decrease, the relative rotation between the driven pulley and the rotary shaft is made freely. That is,
When the running speed of the endless belt tends to decrease,
The rotational angular velocity of the driven pulley is made slower than the rotational angular velocity of the rotating shaft to prevent the contact portion between the endless belt and the driven pulley from being strongly rubbed. In this way, the direction of the stress acting on the rubbed portion between the driven pulley and the endless belt is kept constant, slippage occurs between the endless belt and the driven pulley, or the life of the endless belt is shortened. To prevent

[0007]

In the case of the conventionally known pulleys with a built-in roller clutch, they are arranged in series with each other in the axial direction. Therefore, it is inevitable that the axial dimension (thickness) of the entire pulley with a built-in roller clutch becomes large. In contrast, the space for incorporating the roller clutch built-in pulley is limited,
In particular, the axial dimension is often small. Therefore, realization of a roller clutch built-in type pulley having a smaller axial dimension is desired. The pulley with a built-in roller clutch of the present invention was invented in view of such circumstances.

[0008]

A pulley with a built-in roller clutch according to the present invention includes a sleeve, a pulley, a support bearing, and a roller clutch. The sleeve includes a first inner diameter side cylindrical portion and a first outer diameter side cylindrical portion which are concentric with each other, and the first inner diameter side cylindrical portion among these can be externally fitted and fixed to the rotating shaft. The pulley includes a second inner cylindrical portion and a second outer cylindrical portion that are concentric with each other. And the inner peripheral surface of the second inner diameter side cylindrical portion and the outer peripheral surface of the first inner diameter side cylindrical portion, the inner peripheral surface of the second outer diameter side cylindrical portion and the first outer diameter side cylindrical portion. The inner peripheral surface is arranged concentrically with the sleeve in a state of facing each other. Further, the intermediate portion of the belt can be freely wound around the outer peripheral surface of the second outer diameter side cylindrical portion. The support bearing is provided between the outer peripheral surface of the first inner cylindrical portion and the inner peripheral surface of the second inner cylindrical portion. Then, while supporting the radial load applied to the pulley, the relative rotation between the pulley and the sleeve is made free. Further, the roller clutch is provided in a peripheral portion of the support bearing between an inner peripheral surface of the first outer cylindrical portion and an outer peripheral surface of the second inner cylindrical portion. Then, only when the pulley and the sleeve relatively rotate in a predetermined direction, the transmission of the rotational force between the pulley and the sleeve is made free.

[0009] More preferably, one or both of the following are added to the above configuration to prevent foreign matters such as dust and rainwater from entering the roller clutch. A labyrinth seal formed by bringing a partial surface of a sleeve including an outer peripheral surface of the first outer cylindrical portion and a partial surface of a pulley including an inner peripheral surface of the second outer cylindrical portion close to each other. A seal ring including an elastic material, which is provided in an annular gap portion that allows the installation space of the roller clutch to communicate with the outside and closes the annular gap.

[0010]

In the case of the pulley with a built-in roller clutch of the present invention constructed as described above, since the support bearing and the roller clutch are arranged so as to overlap in the diametrical direction, the dimension in the axial direction can be reduced. . As a result, it becomes easy to install the roller clutch built-in type pulley in a limited space.

[0011]

1 and 2 show a first embodiment of the present invention. Pulley with built-in roller clutch 1
Are the sleeve 2, the pulley 3, the support bearings 4,
And a roller clutch 5. The sleeve 2 is fitted around the rotary shaft 6 so as to be freely fixed thereto.
A belt (not shown) can be freely extended around the outer peripheral surface of the belt.

The sleeve 2 has a first inner cylindrical portion 7 and a first outer cylindrical portion 8 concentric with each other, and one axial end of the first inner cylindrical portion 7 and the first outer cylindrical portion 8. A first annular portion 9 that connects the edges (the right edge in FIG. 1) to each other;
Such a sleeve 2 can be fixed to the rotating shaft 6 by fitting the first inner diameter side cylindrical portion 7 to the rotating shaft 6 by interference fit.

The pulley 3 has a second inner cylindrical portion 10 and a second outer cylindrical portion 11 concentric with each other, and a shaft of the second inner cylindrical portion 10 and the second outer cylindrical portion 11. Second annular portion 12 that connects one edge in the direction (left edge in FIG. 1)
And And, of these, the second inner diameter side cylindrical portion 10
The inner peripheral surface of the first inner diameter side cylindrical portion 7 and the inner peripheral surface of the first outer diameter side cylindrical portion 8 face each other. In this state, it is arranged concentrically with the sleeve 2. Also, the second outer diameter side cylindrical portion 1
An intermediate portion of a belt (not shown) can be freely wound around the outer peripheral surface of the belt 1. In the case of the illustrated example, the outer peripheral surface of the second outer diameter side cylindrical portion 11 is formed by forming irregularities in the circumferential direction on the outer peripheral surface of the second outer diameter side cylindrical portion 11 so that the outer peripheral surface of the second outer diameter side cylindrical portion 11 is geared. And the outer peripheral surface and the stepped belt are freely meshable.

The support bearings 4 are provided between the outer peripheral surface of the first inner cylindrical portion 7 and the inner peripheral surface of the second inner cylindrical portion 10. In the case of the embodiment shown,
As each of these support bearings 4, 4, a pair of ball bearings each having a deep groove type is used. Then, the inner rings 13, 13 constituting the support bearings 4, 4 are fitted to the outer peripheral surface of the first inner diameter side cylindrical portion 7 by interference fit, and the outer rings 14, 14 are similarly connected to the second inner diameter side cylindrical portion. 10
Are tightly fitted to the inner peripheral surface. By installing the support bearings 4 and 4 in this manner, while supporting the radial load applied to the pulley 3 from the belt,
The relative rotation between the pulley 3 and the sleeve 2 is free. The bearings that can be used as support bearings are not limited to deep groove ball bearings. Angular-type ball bearings, needle bearings, sliding bearings, and combinations of these bearings are appropriately selected and used according to the installation space, the applied radial and thrust loads.

The roller clutch 5 is disposed between the inner peripheral surface of the first outer diameter side cylindrical portion 8 and the outer peripheral surface of the second inner diameter side cylindrical portion 10, around the support bearings 4, 4. Is provided. Only when the pulley 3 and the sleeve 2 rotate relative to each other in a predetermined direction, transmission of the rotational force between the pulley 3 and the sleeve 2 is made free. In order to constitute such a roller clutch 5, an inner ring 15 for the roller clutch is fixed to the outer peripheral surface of the second inner cylindrical portion 10 by an interference fit. This roller clutch inner ring 15
Is formed by a hard metal such as bearing steel into a cylindrical shape,
The outer peripheral surface is a cam surface 16 having irregularities as shown in FIG.

Further, an outer ring 17 for a roller clutch is fixed on the inner peripheral surface of the first outer diameter side cylindrical portion 8 by tight fitting. The outer ring 17 for the roller clutch is also formed by pressing a hard metal plate such as bearing steel.
The whole is formed in a cylindrical shape, and flange portions 18a and 18b each having an inward flange shape are formed on both end edges in the axial direction. One of these flange portions 18a and 18b (left side in FIG. 1) is formed before being combined with the other constituent members.
Has the same thickness dimension as that of the main body. On the contrary,
The other (right side in FIG. 1) flange portion 18b is formed to be thin after being combined with other components.

The roller clutch 5 includes an inner peripheral surface of the intermediate portion of the outer race 17 for the roller clutch and an outer peripheral surface of the inner race 15 for the roller clutch. That is, between the inner peripheral surface of the intermediate portion of the outer ring 17 for the roller clutch and the outer peripheral surface of the inner ring 15 for the roller clutch, a cage 19 formed of a synthetic resin in a cage-type cylindrical shape, and a plurality of rollers 20 and A spring (not shown) is provided. The inner peripheral surface of the retainer 19 is engaged with the cam surface 16 of the inner ring 15 for roller clutch to prevent the relative rotation with respect to the inner ring 15 for roller clutch. Each of the rollers 20 is rotatably held by the holder 19. The springs are provided between the retainer 19 and the rollers 20, respectively, and elastically press the rollers 20 in the same direction with respect to the circumferential direction. The retainer 19 may be made of an elastic synthetic resin, and the spring may be provided integrally with the retainer 19.

Thus, the roller clutch inner race 15 and
The roller clutch 5 is composed of a roller clutch outer ring 17, a cage 19, a plurality of rollers 14 and springs, and the pulley on which the roller clutch inner ring 15 is externally fixed by a known operation. 3 and the sleeve 2 in which the roller clutch outer ring 17 is fitted and fixed.
, Only one-way rotational movement can be transmitted.

In the illustrated example, the labyrinth seal 21 is formed by bringing the outer peripheral surface of the first outer cylindrical portion 8 and the inner peripheral surface of the second outer cylindrical portion 11 close to each other. ing. The labyrinth seal 21 prevents foreign matters such as dust and rainwater from entering the roller clutch 5 from the outer diameter side of the roller clutch 5.
The entry of foreign matter from the inner side of the roller clutch 5 is prevented by the seal rings 22 attached to the support bearings 4. Furthermore, although illustration is omitted,
A seal ring containing an elastic material may be provided in an annular gap portion that allows the installation space of the roller clutch 5 to communicate with the outside to close the annular gap, thereby preventing foreign matter from entering the roller clutch 5.

When the rotating shaft 6 of the alternator is driven by the pulley 1 with a built-in roller clutch of the present invention as described above, for example, by the crankshaft of the engine, the end of the rotating shaft 6 is The sleeve 2 is externally fitted and fixed to a portion protruding from the case.
Then, an endless belt is stretched between the drive pulley fixed to the end of the crankshaft and the pulley 3.
At this time, when the rotational angular velocity of the pulley 3 tends to be faster than the rotational angular velocity of the rotary shaft 6 with respect to the rotational direction of the rotary shaft 6, the roller clutch 5 is locked, and the rotation of the pulley 3 The mounting direction is regulated so as to be transmitted to the rotating shaft 6 via the second shaft 2. Conversely, regarding the rotation direction of the rotation shaft 6, the pulley 3
When the rotational angular velocity of the rotary shaft 6 is lower than the rotational angular velocity of the rotary shaft 6, the roller clutch 5 becomes free so that the transmission of rotational force between the pulley 3 and the rotary shaft 6 is prevented.

In particular, in the case of the roller clutch built-in pulley 1 of the present invention, since the support bearings 4 and 4 and the roller clutch 5 are disposed so as to overlap in the diameter direction, the dimension in the axial direction is reduced. it can. As a result, it becomes easy to install the roller clutch built-in pulley 1 in a limited space.

FIG. 3 shows a second embodiment of the present invention.
An example is shown. In the case of this example, the first outer diameter side cylindrical portion 8
Is formed as a conical convex inclined surface, and the inner peripheral surface of the second outer diameter side cylindrical portion 11 is formed as a conical concave inclined surface. The labyrinth seal 21a provided between these two peripheral surfaces is inclined in a direction toward the outside in the diametrical direction toward the opening. By configuring the labyrinth seal 21a in this manner, in the case of the present example, the foreign matter that has entered the labyrinth seal 21a due to the centrifugal force based on the rotation of the sleeve 2 and the pulley 3 enters the opening of the labyrinth seal 21a. Pushed back. Therefore, the effect of preventing foreign matter from entering the installation portion of the roller clutch 5 is further improved. Other configurations and operations are the same as those in the first example described above, and therefore, the same parts are denoted by the same reference numerals, and redundant description will be omitted.

[0023]

The pulley with a built-in roller clutch of the present invention is constructed and operates as described above, so that it can be easily assembled in a limited installation space, and can be easily designed in a vehicle incorporating the pulley with a built-in roller clutch. It can contribute to improvement of the degree of freedom.

[Brief description of the drawings]

FIG. 1 is a partially enlarged sectional view showing a first example of an embodiment of the present invention.

FIG. 2 is a diagram showing only a roller clutch inner ring taken out and viewed from a side in FIG. 1;

FIG. 3 is a partially enlarged sectional view showing a second example of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pulley with built-in roller clutch 2 Sleeve 3 Pulley 4 Support bearing 5 Roller clutch 6 Rotating shaft 7 First inner diameter side cylindrical part 8 First outer diameter side cylindrical part 9 First circular part 10 Second inner diameter side cylindrical part 11 Second Outer diameter side cylindrical portion 12 Second circular ring portion 13 Inner ring 14 Outer ring 15 Inner ring for roller clutch 16 Cam surface 17 Outer ring for roller clutch 18a, 18b Flange portion 19 Cage 20 Roller 21, 21a Labyrinth seal 22 Seal ring

Claims (1)

[Claims] A first inner cylindrical portion and a first outer cylindrical portion which are concentric with each other, wherein the first inner cylindrical portion is externally fixed to a rotating shaft; A second inner diameter side cylindrical portion and a second outer diameter side cylindrical portion are provided, of which the inner peripheral surface of the second inner diameter side cylindrical portion and the outer peripheral surface of the first inner diameter side cylindrical portion are the second outer diameter side. The inner peripheral surface of the cylindrical portion and the inner peripheral surface of the first outer diameter side cylindrical portion are arranged concentrically with the sleeve in a state where they face each other, and a belt is provided on the outer peripheral surface of the second outer diameter side cylindrical portion. A pulley that allows the intermediate portion of the pulley to be freely suspended, and provided between an outer peripheral surface of the first inner cylindrical portion and an inner peripheral surface of the second inner cylindrical portion, while supporting a radial load applied to the pulley. A support bearing that allows relative rotation between the pulley and the sleeve; an inner peripheral surface of the first outer diameter side cylindrical portion; A roller provided at a peripheral portion of the support bearing between the outer peripheral surface of the cylindrical portion and a roller which enables the transmission of rotational force between the pulley and the sleeve only when the pulley and the sleeve relatively rotate in a predetermined direction; A pulley with a built-in roller clutch equipped with a clutch.