JPH11118026A - Pulley device with built-in roller clutch for alternator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the connection of a roller clutch from breaking by the effect of centrifugal force at the time of high speed rotation. SOLUTION: A sleeve 8 is fitted and fixed around a driving shaft of an alternator. An endless belt is hooked around a pulley 7b. Only in the case where rotating speed of the pulley 7b side is a rotating speed or more of the sleeve 8, a roller clutch 16 is connected. The cam surface 22 of the roller clutch 16 is formed on an intermediate part on an inner circumferential surface of an outer wheel 20. A ceramic or hollow parts which is lighter than a full body of a bearing steel is used as a roller 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulley device with a built-in roller clutch for an alternator, which is fixed to an end of a rotating shaft of an alternator as a generator for an automobile and is fixed to an end of a crankshaft of an engine. The alternator is used to drive the alternator by passing an endless belt between them.

[0002]

2. Description of the Related Art The structure of an alternator for generating electric power necessary for an automobile by using an engine for driving the automobile as a driving source is described in, for example, Japanese Patent Application Laid-Open No. 7-139550. FIG. 6 shows an alternator 1 described in this publication. The rotating shaft 3 is rotatably supported inside the housing 2 by a pair of rolling bearings 4, 4. A rotor 5 and a commutator 6 are provided at an intermediate portion of the rotating shaft 3. A driven pulley 7 is provided at one end (right end in FIG. 6) of the rotary shaft 3 protruding outside the housing 2.
Is fixed. In an assembled state to the engine, an endless belt is stretched over the driven pulley 7, and the rotary shaft 3 is rotatably driven by the crankshaft of the engine.

Conventionally, the driven pulley 7 is generally
What was simply fixed to the rotating shaft 3 was used. On the other hand, in recent years, when the traveling speed of the endless belt is constant or increasing, transmission of power from the endless belt to the rotating shaft is freely performed, and when the traveling speed of the endless belt tends to decrease, Various pulley devices with a built-in clutch for an alternator that allow relative rotation between a driven pulley and a rotary shaft have been proposed and are used in part. For example,
JP-A-56-101353, JP-A-8-6144
No. 3, Japanese Patent Publication No. 7-72585, French Patent Publication No. FR2726059A1, and the like describe a pulley device with a built-in clutch for an alternator having the above-described functions. In addition, such an alternator clutch built-in type pulley device is actually used.

FIG. 7 shows a pulley device with a built-in clutch for an alternator described in Japanese Patent Application Laid-Open No. 8-61443. This alternator clutch built-in pulley device has a sleeve 8 that can be fitted and fixed to the rotating shaft 3 of the alternator. A driven pulley 7 a is arranged around the sleeve 8 concentrically with the sleeve 8. A pair of support bearings 9a is provided between the outer peripheral surface of the sleeve 8 and the inner peripheral surface of the driven pulley 7a.
9a and a one-way clutch 10 are provided. Among these, the support bearings 9a, 9a allow the relative rotation between the sleeve 8 and the driven pulley 7a while supporting the radial load applied to the driven pulley 7a. The one-way clutch 10 is used only when the driven pulley 7a tends to rotate relative to the sleeve 8 in a predetermined direction.
The transmission of the rotational force from the driven pulley 7a to the sleeve 8 is allowed.

The reason for using such a pulley device with a built-in clutch for an alternator 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 11 stretched over the drive pulley fixed to the end of the crankshaft also fluctuates finely. on the other hand,
The rotating shaft 3 of the alternator 1 (FIG. 6) driven to rotate by the endless belt 11 via the driven pulley 7a includes the rotating shaft 3, the rotor 5 fixed to the rotating shaft 3, and the commutator 6 (FIG. 6). Does not fluctuate so sharply. Therefore, if the driven pulley 7a is simply fixed to the rotating shaft 3, the endless belt 11 and the driven pulley 7
a tends to rub in both directions. As a result, stress is repeatedly applied in a different direction to the endless belt 11 that rubs against the driven pulley 7a, so that the endless belt 11 easily slips between the endless belt 11 and the driven pulley 7a. May shorten the life of the device.

The endless belt 1 based on the friction between the outer peripheral surface of the driven pulley 7a and the inner peripheral surface of the endless belt 11 as described above.
The reduction in the service life of 1 also occurs by repeating acceleration and deceleration during traveling. That is, the driving force is transmitted from the endless belt 11 side to the driven pulley 7a side during acceleration, while the driven pulley 7a that continues to rotate based on inertia as described above during deceleration is transmitted from the endless belt 11 to the driven pulley 7a side. A braking force acts. The braking force and the driving force are the same as those of the endless belt 11.
Acts as a friction force in the opposite direction to the inner peripheral surface of
Again, this causes a reduction in the life of the endless belt 11. In particular, in the case of a vehicle equipped with an exhaust brake like a truck, the deceleration of the decrease in the rotation of the crankshaft when the accelerator is off is remarkable, and the friction applied to the inner peripheral surface of the endless belt 11 based on the braking force is increased. As a result of an increase in force, the above-mentioned life is significantly reduced.

Therefore, by using the alternator clutch built-in pulley device as the driven pulley 7a as described above, when the running speed of the endless belt 11 is constant or tends to increase, the driven pulley 7a
When the running speed of the endless belt 11 tends to decrease, the transmission of the rotational force from the
The relative rotation between the driven pulley 7a and the rotating shaft 3 is made free. That is, when the running speed of the endless belt 11 tends to decrease, the rotational angular speed of the driven pulley 7a is made slower than the rotational angular speed of the rotary shaft 3 so that the contact between the endless belt 11 and the driven pulley 7a is reduced. Prevents the contact parts from rubbing strongly. In this way, the direction of the stress acting on the rubbed portion between the driven pulley 7a and the endless belt 11 is made constant,
This prevents slippage between the endless belt 11 and the driven pulley 7a or prevents the life of the endless belt 11 from being shortened.

[0008]

When a roller clutch is used as the one-way clutch 10 constituting the alternator clutch built-in pulley device which is constructed and operates as described above, the roller clutch is securely connected even at high speed rotation. Consideration must be given to maintaining the state. That is, the roller clutch disconnects and connects even when the member having the inner ring fixedly fitted to the outer ring and the member having the outer ring fixed to the inside are slightly rotated relative to each other.
It is suitable as the one-way clutch 10 as described above. or,
In the roller clutch, it is necessary to form a cam surface which is uneven in the circumferential direction on one of the inner peripheral surface of the outer race and the outer peripheral surface of the inner race. In particular, in order to increase the torque that can be transmitted between the outer ring and the inner ring, it is preferable to form the cam surface on the inner peripheral surface of the outer ring.

However, when the cam surface is formed on the inner peripheral surface of the outer race, a plurality of rollers constituting the roller clutch move to the ramp portion of the cam surface based on centrifugal force during high-speed rotation, and the roller clutch is driven. Is disconnected, endless belt 1
In spite of the fact that the traveling speed 1 is constant or increasing, the transmission of rotational force from the driven pulley 7a to the rotary shaft 3 may not be performed. In this manner, the movement of each roller to the ramp portion on the cam surface based on the centrifugal force can be prevented by increasing the elasticity of the spring that presses each roller in the circumferential direction. When it is increased, the contact pressure between the rolling surface of each roller and each of the peripheral surfaces becomes large, not only the durability of the roller clutch is impaired, but also the running speed of the endless belt 11 tends to decrease. It cannot be adopted because it causes a problem such as that the connection of the roller clutch is hardly disconnected. The roller clutch built-in type pulley device for an alternator of the present invention was invented in view of such circumstances.

[0010]

A pulley device with a built-in roller clutch according to the present invention is provided around a rotating shaft of an alternator.
A driven pulley that is arranged concentrically with the rotating shaft, and is provided between an outer peripheral surface of the rotating shaft and an inner peripheral surface of the driven pulley, and supports the radial load applied to the driven pulley to form a connection between the rotating shaft and the driven pulley. Provided between the outer peripheral surface of the rotating shaft and the inner peripheral surface of the driven pulley, and provided only when the driven pulley tends to rotate relative to the rotating shaft in a predetermined direction. A roller clutch for freely transmitting a rotational force between the driven pulley and the rotating shaft; A cam surface for constituting the roller clutch is formed on the inner peripheral surface of the driven pulley or the inner peripheral surface of the outer ring fixed to the driven pulley, and a plurality of cam surfaces arranged on the inner peripheral surface are formed. As the roller, a roller made of bearing steel and lighter than a solid roller is used.

[0011]

In the case of the pulley device with a built-in roller clutch of the present invention constructed as described above, each roller is moved outward in the diametrical direction even during high-speed rotation, because a lightweight roller is used. Power is small. Therefore, the roller clutch can be maintained in the connected state regardless of the centrifugal force applied to each of the rollers at the time of high-speed rotation.

[0012]

1 to 3 show a first embodiment of the present invention. The sleeve 8 is formed in a cylindrical shape as a whole. The sleeve 8 is externally fitted and fixed to the end of the rotating shaft 3 (see FIGS. 6 and 7) of the alternator, and is rotatable together with the rotating shaft 3. For this reason, in the illustrated example, a female spline portion 12 is formed on the inner peripheral surface of the intermediate portion of the sleeve 8, and a male spline portion (not shown) formed on the outer peripheral surface of the female spline portion 12 and the end of the rotating shaft 3. And are freely engageable.
The structure for preventing the relative rotation between the rotating shaft 3 and the sleeve 8 may be replaced by a screw, a fitting of non-cylindrical surfaces, a key engagement, or the like instead of the spline.

A driven pulley 7b is disposed concentrically with the sleeve 8 around the sleeve 8 as described above. The driven pulley 7b is integrally formed by subjecting a metal material such as a steel plate or an aluminum alloy plate to plastic working such as press working, drawing work, and forging work, so that the inner diameter side cylindrical portion 13 and the outer diameter side cylindrical portion are formed. It has a substantially U-shaped cross-section having 14 and a connecting portion 15. The inner diameter side cylindrical portion 13 is formed relatively thick in order to mount the support bearings 9 and 9 and the roller clutch 16 described below inside thereof. or,
The outer-diameter-side cylindrical portion 14 is arranged concentrically with the inner-diameter-side cylindrical portion 13 with a cross-sectional shape of the inner peripheral surface in the width direction as a waveform. A part of an endless belt called a so-called poly V belt is wound around the outer peripheral surface of such an outer diameter side cylindrical portion 14.
Further, the outer peripheral edge of the connecting portion 15 formed in a ring shape is one end edge in the axial direction of the outer diameter side cylindrical portion 14 (the right end edge in FIG. 1).
Similarly, the inner peripheral edge is connected to one end in the axial direction of the inner diameter side cylindrical portion 13 to connect the outer diameter side cylindrical portion 14 and the inner diameter side cylindrical portion 13 concentrically with each other.

A pair of support bearings 9 and 9 and one roller clutch 16 are provided between the outer peripheral surface of the sleeve 8 configured as described above and the inner peripheral surface of the driven pulley 7b configured as described above. Are provided. Support bearings 9, 9 of these
Allows the relative rotation between the sleeve 8 and the driven pulley 7b while supporting the radial load applied to the driven pulley 7b. In the illustrated example, a roller bearing is used as each of the support bearings 9 so that a large radial load can be supported. Further, the roller clutch 16 enables the transmission of the rotational force between the driven pulley 7b and the sleeve 8 only when the driven pulley 7b tends to rotate in a predetermined direction with respect to the sleeve 8.

In order to constitute such support bearings 9 and 9 and the roller clutch 16, the outer peripheral surface of the sleeve 8
The support bearing inner races 17 and 17 and the roller clutch inner race 18 are externally fitted and fixed by interference fit. Each of the inner races 17 and 18 is formed entirely of a hard metal such as bearing steel into a cylindrical shape, and the outer peripheral surfaces are respectively cylindrical surfaces. In addition, the inner rings 17, 17 for the respective support bearings
Is provided with an outward flange-like inner ring side flange portion 1 at each one end edge.
By forming 9, the whole is formed in a cylindrical shape with an L-shaped cross section. Inner rings 17 for each such support bearing
With the inner ring side flanges 19 located on opposite sides, the sleeve 8 is fitted over the sleeve 8 by interference fit, and the respective leading edges abut the axial ends of the roller clutch inner ring 18. .

On the other hand, an outer ring 20 is fixedly fitted on the inner peripheral surface of the intermediate portion of the driven pulley 7b by interference fitting.
The outer ring 20 is formed in a cylindrical shape as a whole by pressing a hard metal plate material such as bearing steel or the like, and the outer ring side flange portions 21a each having an inward flange shape are formed at both axial end edges. 21b. In addition, one of the outer ring side flange portions 21a and 21b (left side in FIG. 1) is formed before being combined with other constituent members. It has equivalent thickness dimensions. On the other hand, the other outer ring side flange portion 21b (right side in FIG. 1) is formed to be thin after being combined with other components. A cam surface 22, which is an uneven surface extending in the circumferential direction as shown in FIG. 2, is formed at an intermediate portion in the axial direction of the inner peripheral surface of the outer ring 20, and both axial portions are cylindrical surfaces. I have.

The roller clutch 16 includes a cam surface 22 formed on the inner peripheral surface of the intermediate portion of the outer race 20 and the outer peripheral surface of the inner race 18 for the roller clutch. That is, between the cam surface 22 and the outer peripheral surface of the roller clutch inner ring 18, a cage 23 formed of a synthetic resin in a cage-shaped cylindrical shape, and each of the cages 23 is formed in a columnar shape as shown in FIG. 3. A plurality of rollers 24 and each of these rollers 2
4 and the same number of springs 25 are provided. In the case of this example, each roller 24 is made of ceramic, which is lighter than general bearing steel, as a material for forming a roller for a roller clutch. The spring 25 may be formed integrally with the synthetic resin retainer 23 in addition to locking a metal leaf spring to the retainer 23. Also, a part of the outer peripheral surface of the retainer 23 is engaged with the cam surface 22 so that
Relative rotation with respect to. Each of the rollers 2
Numerals 4 are rotatably held by the holder 23, respectively. The springs 25 are provided between the retainer 23 and the rollers 24, respectively, and elastically press the rollers 24 in the same direction with respect to the circumferential direction.

Thus, the roller clutch inner race 18 and
The roller clutch 1 comprising an outer race 20, a cage 23, and a plurality of rollers 24 and springs 25, respectively.
6 transmits, based on a known operation, only one-way rotational movement between the sleeve 8 to which the inner ring 18 for the roller clutch is externally fixed and the driven pulley 7b to which the outer ring 20 is internally fixed. Be free. In the example of FIG. 2, the inner race 18 for the roller clutch and the outer
0 rotates clockwise in FIG. The driven pulley 7
b, the running speed of the endless belt 11 (FIG. 7) is constant or increasing.
However, based on the elasticity of the spring 25 and the rotation of the outer ring 20, there is a tendency that the width between the outer peripheral surface of the roller clutch inner ring 18 and the cam surface 22 is narrow. For this reason, from the outer ring 20 to the roller clutch inner ring 18
The power is transmitted to. On the other hand, when the traveling speed of the endless belt 11 tends to decrease, the inner race 18 for the roller clutch is
, It tends to rotate clockwise. In this state, each of the rollers 24 moves between the outer peripheral surface of the roller clutch inner race 18 and the cam surface 22 against the elasticity of the spring 25 based on the force received from the outer peripheral surface of the roller clutch inner race 18. It tends to move in the clockwise direction in FIG. As a result, the roller clutch inner race 18 becomes rotatable inside the outer race 20.

When the roller clutch 16 is rotated at a high speed, the rollers 24 are partially diametrically outwardly recessed (ramp portions) on a part of the cam surface 22 due to the centrifugal force applied to the rollers 24. It tends to get into it. When the centrifugal force is large and the force of each of the rollers 24 trying to enter the ramp portion is greater than the elasticity of the spring 25, the rollers 24 have a constant or increasing tendency despite the running speed of the endless belt 11. The connection of the clutch 16 is disconnected. On the other hand, in the case of the roller clutch built-in type pulley device of the present invention, since each of the rollers 24 is made of lightweight ceramic, even if the centrifugal force acting on each of the rollers 24 is too large even at high speed rotation. Instead, a small force is required to move these rollers 24 outward in the diameter direction. Therefore, regardless of the centrifugal force applied to each roller 24 during high-speed rotation, the roller clutch 16
Can be maintained in a connected state.

Each of the support bearings 9 includes the inner ring 17 for the support bearing and a portion of the outer ring 20 near both ends in the axial direction. That is, the outer peripheral surfaces of the support bearing inner rings 17 and 17 and the outer ring 20
A cage 26 formed of a synthetic resin in a cage-like cylindrical shape, and a plurality of rollers 27 rotatably held by the cage 26 between the inner peripheral surfaces of the portions near the axial ends. Are arranged to constitute a radial roller bearing.

Floating washers 28, 28 are provided between the outer surfaces of the outer ring-side flanges 21a, 21b and the inner surfaces of the inner ring-side flanges 19, 19, respectively. 21a, 21b and inner ring side flange 19, 1
9 and freely mounted relative to it. Each of the above-mentioned floating washers 28, 28 is made of a metal having self-lubricating properties such as copper, a metal treated with a tuftride, or a metal material impregnated with a lubricating oil such as an oil-impregnated metal, or a polyamide resin, a polyacetal resin, or a polytetrafluoride. It is formed in a ring shape from a synthetic resin having a low friction coefficient such as an ethylene resin. Such floating washers 28, 28
The outer ring side flanges 21a and 21b and the inner ring side flanges 19 and 1
9 and loosely clamped. Further, the floating washers 28, 28
Guidance (prevention of displacement in the radial direction) is provided by the outer peripheral surfaces of the first and second pulleys 7 and 17 or the inner peripheral surface of the driven pulley 7b.

The gaps between the inner peripheral surfaces of both ends in the axial direction of the outer ring 20 and the outer peripheral surfaces of the inner rings 17, 17 are closed by seal rings 29, 29, respectively. Each of these seal rings 29, 29 is composed of a metal core 30 formed in an annular shape by a metal plate such as a steel plate, and an elastic material 31 such as rubber or elastomer. Each of the above-mentioned seal rings 29, 29 is internally fitted to the inner peripheral surfaces of both ends of the outer ring 20 by interference fitting in a state where the outer diameter of the elastic member 31 is elastically reduced. Then, the leading edges of the seal lips provided on the elastic members 31, 31 are provided on the outer peripheral surface of the intermediate portion of the support bearing inner rings 17, 17 and the inner surfaces of the outer ring side flange portions 21a, 21b. Sliding contact.

Further, the outer ring side and inner ring side flanges 21a,
A labyrinth is provided in a portion where the floating washers 28 and 28 are provided. That is, the outer diameter of each of the inner ring side flanges 19, 19 is made slightly smaller than the inner diameter of the inner diameter side cylindrical portion 13 constituting the driven pulley 7b. It is made to approach the inner peripheral surface of the inner diameter side cylindrical portion 13. Further, the outer diameter of each of the floating washers 28, 28 is made slightly smaller than the inner diameter of the inner diameter side cylindrical portion 13, and the inner diameter of each of the floating washers 28, 28 is reduced to the cylindrical portion of each of the support bearing inner rings 17, 17. 32, slightly larger than the outer diameter of each of these floating washers 2.
The inner and outer peripheries of the inner and outer surfaces of the cylindrical portions 32 and 32 or the inner peripheral surface of the inner cylindrical portion 13 are brought close to each other. Further, the inner diameters of the outer ring side flanges 21a and 21b are
The outer diameter of each of the cylindrical portions 32 is slightly larger than the outer diameter of each of the cylindrical portions 32, 32 so that the inner peripheral edges of the outer ring side flange portions 21a, 21b and the outer peripheral surfaces of the cylindrical portions 32, 32 are brought close to each other. The adjacent portions of the peripheral edge and the peripheral surface of each of these members function as labyrinth seals, and foreign substances such as dust existing around the
This is a resistance against entering the seal rings 29, 29.

When the rotating shaft 3 of the alternator 1 is driven to rotate by, for example, an engine crankshaft by the roller clutch built-in type pulley device of the present embodiment configured as described above, the alternator 1 is driven at the end of the rotating shaft 3. The portion of the sleeve 8 protruding from the housing 2 (FIG. 6)
Is externally fixed. Then, an endless belt 11 (FIG. 7) is stretched between the drive shaft fixed to the end of the crankshaft and the driven pulley 7b. At this time, when the rotational angular velocity of the driven pulley 7b tends to be faster than the rotational angular velocity of the rotary shaft 3 with respect to the rotation direction of the rotary shaft 3, the roller clutch 16 is locked, and the rotation of the driven pulley 7b is stopped. The mounting direction is regulated so as to be transmitted to the rotating shaft 3 via the sleeve 8. Conversely, when the rotational angular velocity of the driven pulley 7b is lower than the rotational angular velocity of the rotary shaft 3 with respect to the rotational direction of the rotary shaft 3, the roller clutch 16 becomes free,
The transmission of rotational force between the driven pulley 7b and the rotary shaft 3 is prevented.

In the case of the illustrated example, the inertial mass of the driven pulley 7b can be reduced while keeping the diameter of the driven pulley 7b (without reducing the diameter). That is, the outer diameter side cylindrical portion 1 to which a part of the endless belt 11 is to be extended.
Reference numeral 4 denotes a thin wall, and the inertial mass of the outer diameter side cylindrical portion 14 is limited. A space 34 exists between the inner peripheral surface of the outer cylindrical portion 14 and the outer peripheral surface of the inner cylindrical portion 13. Therefore, even if the diameter of the outer diameter side cylindrical portion 14 is secured in order to secure the torque for driving the rotating shaft 3, the moment associated with the rotation of the driven pulley 7b does not increase. For this reason, the roller clutch 16
At the moment when they are connected (locked), the roller 24, the outer ring 20,
The roller clutch 16 such as the inner ring 18 for the roller clutch
The impact load applied to the component parts can be reduced, and the durability of the roller clutch 16 can be improved.

Further, in the case of the example shown in the drawing, it is possible to prevent the constituent members from being worn by foreign substances such as dust existing around them, thereby ensuring sufficient durability. That is, the outer ring side flange portion 21
a, 21 b and floating washers 28, 28 which are freely rotatable relative to the inner ring side flanges 19, 19.
Are the outer ring 20 and the inner rings 17, 1
7 while supporting the thrust load acting between the outer ring-side flanges 21a, 21b and the inner ring-side flanges 19, 19, respectively. That is, although the roller clutch 16 has a function of restricting the direction of transmission of the rotational force between the sleeve 8 and the driven pulley 7b, it prevents the sleeve 8 and the driven pulley 7b from shifting in the thrust direction. No function. Each of the support bearings 9, 9, which are radial roller bearings, has a function of supporting a large radial load, but also has a function of preventing the sleeve 8 and the driven pulley 7b from shifting in the thrust direction. Absent. Therefore, in the case of the illustrated pulley device with a built-in roller clutch, each of the outer ring side flange portions 21
The sleeve 8 and the driven pulley 7b are prevented from shifting in the thrust direction by the a, 21b, the inner ring side flanges 19, 19, and the floating washers 28, 28. Moreover, the outer ring side flanges 21a, 21b, each made of hard metal, and the inner ring side flanges 19, 19 are prevented from directly rubbing each other, and these respective flanges 21a, 21
At the same time, the relative displacement between the sleeve 8 and the driven pulley 7b is smoothly performed.

At both ends of the outer race 20, seal rings 29, 29 are mounted, respectively. These seal rings 29, 29 close the gap between the inner peripheral surfaces of both ends of the outer ring 20 and the outer peripheral surfaces of the intermediate portions of the inner rings 17, 17 for the support bearings. It prevents foreign substances such as refuse from entering the installation portion 16. And it contributes to prevention of wear of the components of these support bearings 9 and 9 and the roller clutch 16.
Further, in the case of the illustrated example, each of these seal rings 2
Since a plurality of stages of labyrinth seals are provided on the outer portions of the seal rings 9 and 29, the amount of foreign matter reaching the seal rings 29 and 29 is reduced. For this reason, the amount of foreign substances that reach the installation portions of the support bearings 9 and 9 and the roller clutch 16 beyond these seal rings 29 and 29 is extremely small. As a result, it is possible to further improve the effect of preventing the components of the support bearings 9 and 9 and the roller clutch 16 from being worn. In the illustrated example, the support bearings 9 and 9 and the roller clutch 16 are used.
Is provided between the outer peripheral surface of the sleeve 8 externally fitted and fixed to the end of the rotating shaft 3 (FIGS. 6 and 7) and the inner peripheral surface of the driven pulley 7b, but the sleeve 8 is omitted. You can do it. In this case, the support bearings 9 and 9 and the roller clutch 16 are provided between the outer peripheral surface of the end of the rotating shaft 3 and the inner peripheral surface of the driven pulley 7b. Also, in consideration of cost and workability, one of the support bearing inner rings 17, 17,
Alternatively, the roller clutch inner ring 18 may be integrated with the sleeve 8. Further, the cam surface forming portion of the outer race 20 is
It can be integrated with the driven pulley 7b.

Next, FIG. 4 shows a second embodiment of the present invention.
An example is shown. In the case of the first example described above, the lock of the roller clutch 16 is released based on the centrifugal force when the rotational angular velocity of the driven pulley 7b tends to be equal to or faster than the rotational angular velocity of the rotary shaft 3. In order to reduce the weight of the roller 24, the roller 24 is made of ceramic. On the other hand, in the case of this example, the plurality of rollers 24a constituting the roller clutch are
Each is formed in a hollow cylindrical shape. Therefore, even if each of these rollers 24a is made of bearing steel having a higher specific gravity than ceramic, if the rotational angular velocity of the driven pulley 7b tends to be equal to or faster than the rotational angular velocity of the rotary shaft 3, centrifugation is performed. The release of the lock of the roller clutch 16 based on the force can be prevented. The configuration and operation of the other parts are the same as in the case of the first example described above.

FIG. 5 shows a third embodiment of the present invention.
An example is shown. In the case of this example, concave portions 33, 33 are respectively formed on both axial end surfaces of the plurality of rollers 24b constituting the roller clutch, and the weight of each roller 24b is reduced by the volume of each concave portion 33, 33. I'm trying. For this reason, even if each of these rollers 24b is made of bearing steel having a higher specific gravity than ceramic, if the rotational angular velocity of the driven pulley 7b tends to be equal to or faster than the rotational angular velocity of the rotary shaft 3, centrifugation is performed. The release of the lock of the roller clutch 16 based on the force can be prevented. The configuration and operation of the other parts are the same as those of the first example and the second example described above.

[0030]

The pulley device with a built-in roller clutch for an alternator according to the present invention is constructed and operates as described above, so that accidental disconnection of the roller clutch during high-speed rotation is prevented, and the alternator is prevented from being disconnected. Can be driven stably.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view showing a first example of an embodiment of the present invention.

FIG. 2 shows a state in which a driven pulley and a sleeve are removed,
FIG. 2 is an enlarged sectional view taken along the line AA of FIG. 1.

FIGS. 3A and 3B are diagrams showing only a roller for a roller clutch, wherein FIG. 3A is a side view and FIG. 3B is an end view.

FIG. 4 is a view similar to FIG. 3, showing a second example of the embodiment of the present invention;

FIG. 5 is a view similar to FIG. 3, showing the third example.

FIG. 6 is a sectional view showing an example of a conventionally known alternator.

FIG. 7 is a partial cross-sectional view showing one example of a conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alternator 2 Housing 3 Rotating shaft 4 Rolling bearing 5 Rotor 6 Commutator 7, 7a, 7b Followed pulley 8 Sleeve 9, 9a Support bearing 10 One-way clutch 11 Endless belt 12 Female spline part 13 Inner diameter side cylinder part 14 Outer diameter side cylinder Part 15 Connecting part 16 Roller clutch 17 Inner ring for support bearing 18 Inner ring for roller clutch 19 Inner ring side flange part 20 Outer ring 21a, 21b Outer ring side flange part 22 Cam surface 23 Retainer 24, 24a, 24b Roller 25 Spring 26 Retainer 27 Roller 28 Floating washer 29 Seal ring 30 Core metal 31 Elastic material 32 Cylindrical part 33 Recess 34 Space

Claims (1)

[Claims] 1. A driven pulley disposed concentrically with a rotating shaft of an alternator, between an outer peripheral surface of the rotating shaft and an inner peripheral surface of the driven pulley, and a radial acting on the driven pulley. A support bearing for freely rotating the rotating shaft and the driven pulley while supporting the load, provided between an outer peripheral surface of the rotating shaft and an inner peripheral surface of the driven pulley,
A roller clutch that allows transmission of rotational force between the driven pulley and the rotating shaft only when the driven pulley tends to rotate relative to the rotating shaft in a predetermined direction,
A cam surface for constituting the roller clutch is formed on the inner peripheral surface of the driven pulley or the inner peripheral surface of the outer ring fixedly fitted to the driven pulley, and as a plurality of rollers disposed on the inner peripheral surface. A pulley device with a built-in roller clutch for alternator, using rollers made of bearing steel and lighter than solid rollers.