JP2000234667A - Pulley device with built-in roller clutch for alternator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize frictional heat, and to prevent the degradation of grease by using a material having specific worked penetration as the grease filled in a roller clutch part in a pulley device for supporting a pulley by a sleeve fitted/installed on a rotary shaft via support bearings and a roller clutch. SOLUTION: A pulley 7b is rotatably supported via support bearings 9a, 9a and a roller clutch 10a on the periphery of a cylindrical sleeve 8a nonrotatably joined to a rotary shaft of an alternator via a female spline part 18 formed on an intermediate part inner peripheral surface. In this case, the roller clutch 10a having plural rollers 16a interposed between an inner/outer races 24, 25 is interposed between a pair of support bearings 9a, 9a. A material having worked penetration not less than 265 is used as grease for lubricating this roller clutch 10a. Resiliency of a spring for pressing the plural rollers 16a in the roller clutch 10a in the circumferential direction is respectively set in a range of 20 to 200 gf.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND 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 which is a generator for an automobile and fixed to an end of a crankshaft of an engine. The alternator is used to drive the alternator by wrapping an endless belt between the drive pulleys.

[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. 3 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 pulley 7 is fixed to a portion of the rotating shaft 3 protruding outside the housing 2 at one end (the right end in FIG. 3). In an assembled state to the engine, an endless belt is wrapped around the pulley 7, and the rotary shaft 3 is rotatably driven by the crankshaft of the engine.

Conventionally, a pulley simply fixed to the rotary shaft 3 has been 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 roller clutch for an alternator that allow the relative rotation between the pulley and the rotation shaft have been proposed and used in part. For example, JP-A-56-101353, JP-A-7-317807
JP-A-8-61443, JP-A-8-226462
JP, Kokoku 7-72585 discloses, in French Patent Publication FD _o 2726059A1, etc., have been described for an alternator roller clutch built-in type pulley apparatus having such functions described above.

[0004] FIG.
1 shows a pulley device with a built-in roller clutch for an alternator described in Japanese Unexamined Patent Application Publication No. H11-157,004. This alternator roller clutch built-in type pulley device has a sleeve 8 which can be fitted and fixed to the rotating shaft 3 of the alternator 1 (FIG. 3).
A pulley 7 a is arranged around the sleeve 8 concentrically with the sleeve 8. A pair of support bearings 9 and 9 and a roller clutch 10 are provided between the outer peripheral surface of the sleeve 8 and the inner peripheral surface of the pulley 7a. Among these, the support bearings 9, 9 are provided with the pulley 7a.
The relative rotation between the sleeve 8 and the pulley 7a is made free while supporting the radial load applied to the shaft. Further, the roller clutch 10 can freely transmit the rotational force from the pulley 7a to the sleeve 8 only when the pulley 7a tends to rotate relative to the sleeve 8 in a predetermined direction.

The outer peripheral surface of the intermediate portion of the inner ring 11 which constitutes the roller clutch 10 and is fitted and fixed to the sleeve 8 is
A plurality of concave portions 12 called ramp portions are formed at equal intervals in the circumferential direction, and the outer peripheral surface of the intermediate portion is a cam surface 13. The outer peripheral surfaces of both ends of the inner ring 11 are inner ring raceways 14 for the support bearings 9. On the other hand, the roller clutch 10 is constituted,
The inner peripheral surface of the outer ring 15 externally fitted and fixed to the pulley 7a is a simple cylindrical surface over substantially the entire length. The plurality of rollers 16, 16, which constitute the roller clutch 10 together with the inner ring 11 and the outer ring 15, are connected to the clutch holder 1.
7, it is supported so as to be freely displaceable in the rolling and circumferential directions. A spring is provided between the column provided on the clutch retainer 17 and each of the rollers 16, and these rollers 16 are elastically pressed in the same direction with respect to the circumferential direction.

The reason for using the pulley device with a built-in roller clutch for an alternator as described above is as follows. For example, when the driving engine is a diesel engine, the rotation angular velocity of the crankshaft greatly fluctuates during low rotation, such as during idling. As a result, the running speed of the endless belt (not shown), which runs 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, which is driven to rotate by the endless belt via the pulley 7a, is connected to the rotating shaft 3 and the inertial mass of the rotor 5 and the commutator 6 (FIG. 3) fixed to the rotating shaft 3. And does not fluctuate so rapidly. Therefore, when the pulley 7a is simply fixed to the rotating shaft 3, the endless belt and the pulley 7a tend to rub in both directions with a change in 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 pulley 7a, so that slipping easily occurs between the endless belt and the pulley 7a, or the life of the endless belt is shortened. Or cause

[0007] The life of the endless belt due to friction between the outer peripheral surface of the pulley 7a and the inner peripheral surface of the endless belt as described above is also caused by repeated acceleration and deceleration during traveling. That is, while the driving force is transmitted from the endless belt side to the pulley 7a side during acceleration, the braking force from the endless belt acts on the pulley 7a that continues to rotate based on inertia as described above during deceleration. I do. The braking force and the driving force act as frictional forces on the inner peripheral surface of the endless belt in a direction opposite to that of the endless belt, and also cause a reduction in the life of the endless belt. In particular, in the case of a vehicle equipped with an exhaust brake such as a truck, the deceleration of the decrease in rotation of the crankshaft when the accelerator is off is remarkable, and the frictional force applied to the inner peripheral surface of the endless belt based on the braking force As a result, the life is remarkably reduced.

Accordingly, by using the pulley device with a built-in roller clutch for the alternator as the pulley 7a as described above, when the running speed of the endless belt is constant or tends to increase, the pulley 7a rotates. The rotation of the pulley 7a and the rotary shaft 3 can be freely rotated when the running speed of the endless belt tends to decrease. That is, when the traveling speed of the endless belt tends to decrease, the rotational angular speed of the pulley 7a is made slower than the rotational angular speed of the rotary shaft 3 so that the contact portion between the endless belt and the pulley 7a becomes strong. Prevent rubbing. Thus, the pulley 7
The direction of the stress acting on the rubbing portion between the endless belt and the endless belt is kept constant to prevent the occurrence of slippage between the endless belt and the pulley 7a or to reduce the life of the endless belt.

[0009]

In the case of a conventional pulley device with a built-in roller clutch for an alternator, each roller 1
The characteristics of grease sealed in the space between the outer peripheral surface of the inner race 11 and the inner peripheral surface of the outer race 15 in order to lubricate the roller clutch 10 and the resilience of the spring pressing the springs 6 and 16 in the same circumferential direction. I didn't consider the relationship. For this reason, when the locking should be performed to transmit the rotational force between the inner ring 11 and the outer ring 15, the locking is not reliably performed, or the elasticity of the spring is excessive, so that the inner ring 11 and the outer ring 15 are relatively rotated. During the overrun, the frictional force acting on the contact portion between the rolling surfaces of the rollers 16 and the inner peripheral surface of the outer ring 15 may be increased. If the lock becomes uncertain, the rotational drive of the alternator 1 becomes uncertain, which causes an insufficient power generation. Also, if the frictional force acting on the abutting portion between the two surfaces during overrun increases, the frictional heat generated at the abutting portion increases, and the grease is quickly thermally degraded. This causes the durability of the device to be impaired.

In view of such circumstances, the present inventor has proposed the above-mentioned respective rollers 16, which are generally used as the roller clutch 10 to be incorporated in a pulley device incorporating a roller clutch for an alternator.
For a roller clutch having a diameter of 2.5 to 5.0 mm and a length of 7 to 11 mm, an elastic force of a spring for pressing the rollers 16, 16 in the same circumferential direction, and lubricating the roller clutch 10. The evaluation test was performed while variously changing the characteristics of the grease sealed between the outer peripheral surface of the inner ring 11 and the inner peripheral surface of the outer ring 15 as desired. The present inventors have found that the relationship between the elasticity of the spring and the grease properties is particularly important among the characteristics of the grease, and have accomplished the present invention.

[0011]

A pulley device with a built-in roller clutch for an alternator according to the present invention is, like a conventionally known pulley device with a built-in roller clutch for an alternator, capable of being externally fixed to the rotating shaft of the alternator. A sleeve, a pulley disposed concentrically with the sleeve around the sleeve, and an axially intermediate portion of an outer peripheral surface of the sleeve and an axially intermediate portion of an inner peripheral surface of the pulley; A roller clutch that enables the transmission of rotational force between the pulley and the sleeve only when the roller clutch tends to rotate relative to a predetermined direction, and an outer peripheral surface of the sleeve at a position where the roller clutch is sandwiched from both axial sides. And the inner peripheral surface of the pulley, allowing the sleeve and the pulley to rotate freely while supporting the radial load applied to the pulley. And a pair of support bearings. In particular, in the pulley device with a built-in roller clutch for an alternator according to the present invention, the mixing consistency of grease for lubricating the roller clutch is 265 or more, and a plurality of rollers constituting the roller clutch are arranged in a circumferential direction. The elasticity of the spring pressing the roller is 20 to 200 gf for each of these rollers.

[0012]

In the pulley device with a built-in roller clutch for an alternator according to the present invention constructed as described above, it is possible to securely lock the rotational force between the sleeve and the pulley when the torque should be transmitted. On the other hand, the frictional heat generated at the time of the overrun in which the sleeve and the pulley are relatively rotated is reduced to prevent the grease from deteriorating and to ensure sufficient durability.

That is, in the case of the pulley device with a built-in roller clutch for an alternator, which is the object of the present invention, the rotation speed at the time of locking becomes close to 20,000 rpm at maximum, and the relative rotation speed of the sleeve and the pulley during overrun However, it can reach up to several thousand rpm. In such an application state, heat generation which is not a problem in the conventional roller clutch application becomes a problem. That is, the PV value (the product of the contact pressure and the sliding speed), which indicates the degree of the sliding friction and greatly affects the calorific value, becomes so large that it cannot be compared with the application of the conventional roller clutch. Although the PV value cannot be lowered by lowering the sliding speed, in the case of the present invention, since the elasticity of the spring is set to 200 gf or less, the PV value is suppressed by lowering the contact pressure, The amount of heat generated at the time of the overrun can be suppressed.

Further, in order to lock the roller clutch in order to transmit the rotational force between the sleeve and the pulley, each roller is pressed in the circumferential direction by the elastic force of the spring, and each roller is pressed. In the gap between the outer peripheral surface of the portion that rotates with the sleeve and the inner peripheral surface of the portion that rotates with the pulley, it is necessary to press the wedge-shaped portion against the portion having a reduced width in the diametric direction. At this time, if there is a grease film on both the peripheral surfaces,
The grease film is pressed against the portion where the width dimension is reduced while being pushed away. At this time, it is preferable that the force required to press each of the rollers is substantially constant regardless of whether or not the grease film exists on both the peripheral surfaces. For this purpose, it is preferable to use a soft grease having a large penetration consistency and being soft. According to the experiment of the present inventor, if a grease having a penetration consistency of 265 or more is used, regardless of whether or not a grease film exists on both of the peripheral surfaces, each of the rollers has a wedge shape. The force required to press is almost constant.

Further, the mixing consistency of the grease slightly decreases with use over a long period of time. Even in such a case, it is necessary to secure the elasticity of the spring so that the roller clutch is securely locked. In the case of the present invention, since the force of each spring pressing the roller in the circumferential direction is set to 20 gf or more, the locked state can be surely realized even if the mixing consistency of the grease is slightly reduced. That is, according to an experiment conducted by the inventor, if the elasticity of each spring is set to 20 kg or more and the penetration of grease is set to 265 or more in the initial state, the life required for the alternator roller clutch built-in pulley device (for example, It was found that the locked state of the roller clutch could be reliably realized within a range of 100,000 km).

Incidentally, in the case of the pulley device with a built-in roller clutch for an alternator, which is the object of the present invention, the rotational speed of the roller clutch reaches a maximum of nearly 20,000 rpm. Therefore, as long as the sleeve is rotating at high speed even during overrun, the rolling surface of each roller is pressed against the inner peripheral surface of the outer ring based on the centrifugal force, and these rolling surfaces and the inner peripheral surface A load of several kgf is applied to the abutment part. When shifting from this state to the locked state, the rollers move together with the outer ring while being pressed against the inner peripheral surface of the outer ring based on centrifugal force, and the width dimension of the gap extending in the diametrical direction among the gaps. Is pressed into a wedge-shaped part. Therefore, in order to shift from the overrun state to the locked state,
The respective springs have elasticity enough to move the rollers (while sliding against the inner peripheral surface of the outer ring) against a load of several kgf applied to the contact portion based on the centrifugal force. No need. Conversely, if these springs have such a large elasticity, heat generation during overrun cannot be suppressed.

[0017]

FIG. 1 shows a first embodiment of the present invention. The sleeve 8a is formed in a cylindrical shape as a whole, and the rotating shaft 3 of the alternator (see FIGS. 3 and 4).
And is rotatable together with the rotating shaft 3. For this reason, in the illustrated example, a female spline portion 18 is formed on the inner peripheral surface of the intermediate portion of the sleeve 8a, and a male spline portion (not shown) formed on the female spline portion 18 and the outer peripheral surface of the end portion of the rotating shaft 3. And are freely engageable. still,
The structure for preventing the relative rotation between the rotating shaft 3 and the sleeve 8a may be replaced with a screw as shown in FIG. 4 described above, a fitting between non-cylindrical surfaces, a key engagement or the like instead of the spline. Is also good. When a screw is used, the cross-sectional shape of the inner peripheral surface of the distal end portion (left end portion in FIG. 1) of the sleeve 8a is hexagonal, and the distal end portion of a tool such as a hexagon wrench can be locked at this portion.

A pulley 7b is arranged concentrically with the sleeve 8a around the sleeve 8a as described above. The pulley 7b has a support bearing 9a described below inside thereof,
9a and the roller clutch 10a are mounted. Further, the outer peripheral surface of the pulley 7b has a cross-sectional shape extending in the width direction and has a waveform, so that a part of an endless belt called a poly-V belt can be passed around.

A pair of support bearings 9a, 9a and one roller clutch 10a are provided between the outer peripheral surface of the sleeve 8a and the inner peripheral surface of the pulley 7b. Among these, the support bearings 9a, 9a allow the relative rotation between the sleeve 8a and the pulley 7b while supporting the radial load applied to the pulley 7b. In the illustrated example, a deep groove ball bearing is used as each of the support bearings 9a, 9a. That is, each of these support bearings 9
a and 9a are deep groove type outer ring raceways 19 on the inner peripheral surface, respectively.
An outer ring 20, 20 having an inner ring track 19, and an inner ring 22, 22 having a deep groove type inner ring track 21, 21 on the outer peripheral surface thereof.
A plurality of rolling elements (balls) 2 provided between the outer raceways 19, 19 and the inner raceways 21, 21 so as to freely roll, respectively;
3 and 23. Each such support bearing 9a, 9
a, the outer rings 20 and 20 are internally fitted and fixed to both ends of the inner peripheral surface of the pulley 7b by interference fit, and the inner rings 22 and 22 are externally fitted and fixed to both ends of the outer peripheral surface of the sleeve 8a by interference fit. Thereby, it is provided between both ends of the outer peripheral surface of the sleeve 8a and both ends of the inner peripheral surface of the pulley 7b.

The roller clutch 10a allows the transmission of the rotational force between the pulley 7b and the sleeve 8a only when the pulley 7b tends to rotate in a predetermined direction with respect to the sleeve 8a. . In order to constitute such a roller clutch 10a, an inner ring 24 for the roller clutch is externally fixed to the outer peripheral surface of the intermediate portion of the sleeve 8a by interference fit. The roller clutch inner ring 24 is formed into a cylindrical shape by subjecting a steel plate such as carburized steel to plastic working such as press working, and has a cam surface 13a formed on the outer peripheral surface. That is, a plurality of concave portions 12a called ramps are formed on the outer peripheral surface of the roller clutch inner ring 24 at regular intervals in the circumferential direction, so that the outer peripheral surface is the cam surface 13a. On the other hand, the inner peripheral surface of the outer ring 25 for roller clutch, which is internally fixed to the inner peripheral surface of the intermediate portion of the pulley 7b by interference fit, is merely a cylindrical surface. In addition, the roller clutch 10a together with the roller clutch inner ring 24 and the roller clutch outer ring 25
A plurality of rollers 16a are provided on the inner ring 24 for the roller clutch, and on a clutch holder 26 made of a synthetic resin which is externally fitted to the inner ring 24 for the roller clutch so as not to be rotatable, in a rolling and circumferential direction. It is slightly displaceable. A spring such as a leaf spring is provided between the column provided on the clutch retainer 26 and each of the rollers 16a, and these rollers 16a are elastically pressed in the same direction with respect to the circumferential direction. ing. Since the basic structure and operation of the roller clutch are well known,
Detailed illustration and description are omitted.

Further, in the case of the present embodiment, the forces by which the plurality of springs press the respective rollers 16a in the circumferential direction, in other words, the respective springs apply the respective rollers 16a to the circumference of the respective recesses 12a. The magnitude of the pressing force on the portion where the distance between the concave portion 12a and the inner peripheral surface of the outer ring 25 for roller clutch is reduced near the end portion in the direction is approximately 1 respectively.
00gf. As grease for filling the inside of the roller clutch 10a, that is, the space between the outer peripheral surface of the inner race 24 for the roller clutch and the inner peripheral surface of the outer race 25 for the roller clutch, in a portion where the respective rollers 16a are installed, A diurea thickener and an ester-based synthetic oil base oil having a mixing consistency of 276 are used.

In the case of the pulley device with a built-in roller clutch for an alternator of the present embodiment constructed as described above, the rotation speed of the pulley 7b over which the endless belt is stretched is controlled by the action of the roller clutch 10a. The torque is transmitted from the pulley 7b to the rotation shaft 3 only when the rotation speed is equal to or higher than the rotation speed of the sleeve 8a fixed to the shaft 3. Conversely, if the rotation speed of the pulley 7b is lower than the rotation speed of the sleeve 8a, the pulley 7b
The connection between the endless belt and the sleeve 8a is cut off, so that an unreasonable (in the braking direction) force is applied to the endless belt.

In particular, in the case of the pulley device with a built-in roller clutch for an alternator of the present invention, the force (load) for pressing each roller 16a in the circumferential direction by each spring is 100.
gf and a certain large value (20 gf or more) and a soft grease having a high mixing consistency is used, so that the sleeve 8a and the pulley 7b are used.
It is possible to reliably lock when the rotational force should be transmitted between the two. On the other hand, the force for pressing the rollers 16a in the circumferential direction is set to about 100 gf, which is not excessively large (200 gf or less), so that the overrun in which the sleeve 8a and the pulley 7b are relatively rotated is performed. The generated frictional heat can be suppressed to a small extent to prevent the grease from deteriorating and to ensure sufficient durability.

Further, in the illustrated example, the outer diameter of the roller clutch inner ring 24 (the diameter of the largest inscribed circle at the bottom of each of the recesses 12a) is determined by the inner rings 22, 22 of the support bearings 9a, 9a. Smaller than the outside diameter of Accordingly, at least the bottom surface of each of the recesses 12a of the outer peripheral surface of the roller clutch inner ring 24 is recessed inward in the diametrical direction from the outer peripheral surfaces of the inner rings 22, 22 constituting the support bearings 9a, 9a. are doing. The inner diameter of the clutch retainer 26 constituting the roller clutch 10a (the diameter of the inscribed circle of the plurality of protrusions formed on the inner peripheral edge of the clutch retainer 26 so as to engage with the concave portions 12a) ) Is equal to or larger than the outer diameter of the roller clutch inner race 24,
Inner rings 22, 2 constituting the support bearings 9a, 9a
2 is smaller than the outside diameter. Therefore, the end portions of the clutch retainer 26 closer to the inner diameter on both axial sides face the axial end surfaces of the inner races 22, 22, respectively, and the clutch retainer 26 is moved by the inner races 22, 22. Displacement in the axial direction (left-right direction in FIG. 1) is prevented.
Therefore, the rollers 16a held by the clutch retainer 26 do not come off from the outer peripheral surface of the roller clutch inner race 24 and the outer peripheral surface of the roller clutch outer race 25. Therefore, in order to prevent the clutch retainer 26 from being displaced in the axial direction, the roller clutch 10a is formed of a hard metal such as carburized steel or bearing steel. To
There is no need to perform any complicated processing, and the cost of the pulley device with a built-in roller clutch for the alternator can be reduced.

At the same time, in the illustrated example, the outer diameter of the clutch retainer 26 is made smaller than the inner diameter of the outer races 20, 20 constituting the support bearings 9a, 9a. Therefore, even when the end of the clutch retainer 26 closer to the inner diameter on one side in the axial direction abuts against the end surface of the inner ring 22 constituting any of the support bearings 9a, the axial one side of the clutch retainer 26 is provided. Does not come into contact with the end surface of the outer ring 20 constituting any of the support bearings 9a. For this reason, the clutch retainer 26 does not rub against the outer ring 20 and the inner ring 22 that rotate relative to each other so that the rotational resistance of the support bearing 9a does not increase.

As a modification of this embodiment, the outer diameter and the inner diameter of the clutch retainer 26 are made larger than those in the illustrated example.
The ends of the clutch retainer 26 that are closer to the outer diameter on both sides in the axial direction and the outer race 2 that constitutes the support bearings 9a, 9a.
The engagement of the clutch retainers 26 in the axial direction can also be prevented by the engagement with the axial end surfaces 0 and 20. Further, the clutch retainer 26 is not necessarily provided with the outer races 20, which constitute the support bearings 9 a, 9 a over the entire circumference.
It is not necessary to engage with 20 or the axial end faces of the inner rings 22,22. A part in the circumferential direction is projected in the diametric direction, and the projected part is connected to the outer ring 20, 20 or the inner ring 22, 22.
May be engaged with the axial end surface.

FIG. 2 shows a second embodiment of the present invention.
An example is shown. In the case of this example, a pair of support bearings 9b and 9b, each of which is a radial roller bearing, and one roller clutch 10b are provided between the outer peripheral surface of the sleeve 8a and the inner peripheral surface of the pulley 7c. ing. In order to form the roller clutch 10b, the roller clutch inner ring 24a is externally fixed to the outer peripheral surface of the intermediate portion of the sleeve 8a by interference fit. The roller clutch inner race 24a is made of a hard metal plate material such as bearing steel or SCM4.
15 and the like are formed into a cylindrical shape by a carburized steel plate material, and the outer peripheral surface is a cam surface 13b. Further, in order to constitute the support bearings 9b, 9b, inner rings 22a, 22a are externally fitted to outer peripheral surfaces of both ends of the sleeve 8a by interference fitting. Also, each inner ring 22a, 22a made of a hard metal plate material such as bearing steel or a carburized steel plate material such as SCM415 forms an outer flange-like inner ring flange portion 28 at one end edge of the cylindrical portion 27. By doing so, the whole is formed in a cylindrical shape with an L-shaped cross section.

Each of the inner races 22a, 22a is externally fitted to the sleeve 8a in a state where the inner race side flanges 28 are located on opposite sides, and the leading edge of each inner race 22a is formed by the shaft of the roller clutch inner race 24a. Butts against both edges.
In the case of this example, the outer diameter of the cylindrical portion of each of the inner rings 22a, 22a is set to be larger than the diameter of an inscribed circle related to the bottom of the plurality of recesses 12b formed on the outer peripheral surface of the roller clutch inner ring 24a. I have. And the roller clutch 1
Ob is formed on the inner peripheral surface of the clutch retainer 26b and engages with each of the recesses 12b so that one axial surface of each protruding piece 30, 30 faces the edge of each of the inner rings 22a, 22a. This prevents the clutch retainer 26b from shifting in the axial direction.

On the other hand, the outer ring 20a is attached to the pulley 7c,
The inner fit is fixed by interference fit. This outer ring 20a
Functions not only as an outer ring of the roller clutch 10b but also as an outer ring of each of the support bearings 9b, 9b.
The entire body is formed into a cylindrical shape by performing press working on a plate material of carburized steel such as CM415. Outer ring 20a like this
Are formed on the both ends in the axial direction, respectively, of outer ring side flange portions 29a, 29b in the form of inward flanges. It should be noted that one of the outer ring side flange portions 29a and 29b (left side in FIG. 2) is formed before being combined with the other constituent members, so that the outer ring side flange portion 29a and the main body portion of the outer ring 20a are formed. It has similar thickness dimensions. On the other hand, the outer ring flange 29b on the other side (right side in FIG. 2) is formed to be thin after being combined with other constituent members.

The roller clutch 10b includes an inner peripheral surface of the intermediate portion of the outer race 20a and an outer peripheral surface of the inner race 24a for the roller clutch. That is, between the inner peripheral surface of the intermediate portion of the outer race 20a and the outer peripheral surface of the inner race 24a for the roller clutch, a clutch retainer 26b formed of a synthetic resin into a basket-like cylindrical shape, and a plurality of rollers 16b and A spring (not shown) is provided.
Further, as described above, the retainer 26b for the clutch has the protruding pieces 30, 30 formed on the inner peripheral surface thereof, and the recess 12b forming the cam surface 13b of the inner race 24a for the roller clutch.
To prevent relative rotation with respect to the roller clutch inner ring 24a.

Each of the support bearings 9b, 9b includes each of the inner rings 22a, 22a and a portion near both ends in the axial direction of the outer ring 20a. That is, between the outer peripheral surfaces of the inner rings 22a, 22a and the inner peripheral surfaces of the outer rings 20a near the axial ends, bearing cages 31, 31 each formed of a synthetic resin in a cage-type cylindrical shape. And a plurality of rollers 32, 32 rotatably held by the bearing retainers 31, 31, constitute a radial roller bearing.

Floating washers 33, 33 are provided between the outer surfaces of the outer ring flanges 29a, 29b and the inner surfaces of the inner ring flanges 28, 28, respectively. 29a, 29b and inner ring side flanges 28, 2
8 can be freely rotated. Each of the above-mentioned floating washers 33, 33 is made of a metal having self-lubricating properties such as copper, a metal which has been impregnated with a lubricating oil such as a tufftrided metal or an oil-impregnated metal, or a polyamide resin, a polyacetal resin, 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 33, 33
The outer ring flanges 29a and 29b and the inner ring flanges 28 and 29
8 and loosely clamped. The floating washers 33, 33 guide (prevent radial displacement) by the outer peripheral surfaces of the inner rings 22a, 22a or the inner peripheral surfaces of the pulleys 7c.

The gaps between the inner peripheral surfaces of the axial ends of the outer race 20a and the outer peripheral surfaces of the inner races 22a are closed by seal rings 34, 34, respectively. Each of these seal rings 34, 34 is made up of a core metal 35 and an elastic material 36, and the outer diameter of the elastic material 36 is elastically reduced on the inner peripheral surfaces of both ends of the outer ring 20a. Supports internal fitting. And each elastic material 36, 36
The tip edge of the seal lip provided for each
The outer peripheral surfaces of the intermediate portions of the inner rings 22a, 22a and the inner surfaces of the outer ring side flange portions 29a, 29b are slid or contacted.

In particular, in the case of the pulley device with a built-in roller clutch for an alternator according to the present invention, the force of each spring pressing each of the rollers 16b in the circumferential direction is set to about 40 gf, and the roller clutch 10b is applied to the roller clutch 10b. As the grease to be filled, a grease composed of a thickener made of bentonite and a base oil made of synthetic hydrocarbon and having a mixing consistency of 280 is used. For this reason, in the case of this example, similarly to the case of the above-described first example, the sleeve 8a and the pulley 7c are used.
It is possible to reliably lock when the rotational force should be transmitted between the two. Further, the frictional heat generated at the time of the overrun in which the sleeve 8a and the pulley 7c are relatively rotated is reduced to prevent the grease from deteriorating and to ensure sufficient durability.

[0035]

The pulley device with a built-in roller clutch for an alternator according to the present invention is constructed and operated as described above, so that reliable operation and sufficient durability are realized, and the power generation efficiency of the alternator is ensured. While extending the life of the belt.

[Brief description of the drawings]

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

FIG. 2 is a half sectional view showing the second example.

FIG. 3 is a sectional view showing an example of a conventionally known alternator.

FIG. 4 is a partial cross-sectional view showing an example of the structure of a conventionally known pulley device with a built-in roller clutch for an alternator.

[Description of Signs] 1 Alternator 2 Housing 3 Rotary shaft 4 Rolling bearing 5 Rotor 6 Commutator 7, 7a, 7b, 7c Pulley 8, 8a Sleeve 9, 9a, 9b Support bearing 10, 10a, 10b Roller clutch 11, Inner ring 12, 12a, 12b concave portion 13, 13a, 13b cam surface 14 inner raceway 15, 15a outer race 16, 16a, 16b roller 17 clutch retainer 18 female spline portion 19 outer raceway 20 outer race 21 inner raceway 22, 22a inner race 23 rolling element 24, 24a Inner ring for roller clutch 25 Outer ring for roller clutch 26, 26a, 26b Clutch retainer 27 Cylindrical part 28 Inner ring side flange 29a, 29b Outer ring side flange 30 Projection piece 31 Bearing retainer 32 Roller 33 Floating washer 34 Seal ring 35 core metal 36 elastic material

Claims (1)

[Claims] 1. A sleeve which can be externally fitted and fixed to a rotating shaft of an alternator, a pulley disposed around the sleeve and concentric with the sleeve, an axially intermediate portion of an outer peripheral surface of the sleeve and an inner peripheral surface of the pulley. Provided between the middle part in the axial direction,
A roller clutch that allows the transmission of rotational force between the pulley and the sleeve only when the pulley tends to rotate relative to the sleeve in a predetermined direction, and a roller clutch that sandwiches the roller clutch from both sides in the axial direction. An alternator provided between the outer peripheral surface of the sleeve and the inner peripheral surface of the pulley, and having a pair of support bearings for supporting the radial load applied to the pulley and enabling relative rotation between the sleeve and the pulley. In the roller clutch built-in type pulley device, the mixing consistency of grease for lubricating the roller clutch is 265 or more, and the elasticity of a spring pressing a plurality of rollers constituting the roller clutch in a circumferential direction is: A pulley device with a built-in roller clutch for an alternator, wherein the weight of each roller is 20 to 200 gf.