JP2001012513A - One-way clutch housing type pulley device for alternator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent early thermal deterioration of grease by sealing the grease into a space in which a roller clutch is arranged by an appropriate amount. SOLUTION: A space 29 in which a roller clutch 10 is arranged and spaces 27, 27 in which a plurality of balls 24, 24 composing a pair of support bearings 9, 9 are arranged are partitioned by seal rings 26, 26, selected from the paired seal rings 26, 26 attached to the support bearings 9, 9. Grease is sealed into the space 29 in which the roller clutch 10 by an appropriate amount, that is, 60 to 80% of volumetric percent of the hollow space.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A pulley device with a built-in one-way clutch for an alternator, which is an object of the present invention, is fixed to an end of a rotating shaft of an alternator which is a generator for an automobile, and is attached to an end of a crankshaft of an engine. It is used to drive the alternator by wrapping an endless belt between the fixed drive pulleys.

[0002]

2. Description of the Related Art The structure of an alternator for generating electric power necessary for an automobile 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 driven pulley 7 is provided at one end of the rotating shaft 3 (the right end in FIG. 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 one-way clutch for alternators, which make the relative rotation between the driven pulley and the rotary shaft freely, have been proposed and used in part. For example, JP-A-56-101353, JP-A-7-3
No. 17807, No. 8-61443, No. 8-2
Japanese Patent Publication No. 26462, Japanese Patent Publication No. 7-72585, French Patent Publication FR2726059A1, and the like describe a pulley device with a built-in one-way clutch for an alternator having the above-described functions.

The one-way clutch-incorporated pulley devices described in these documents have a driven pulley having a sleeve which can be externally fitted and fixed to a rotating shaft of an alternator, and which has a cylindrical inner peripheral surface around the sleeve. Are arranged concentrically with this sleeve. A pair of support bearings and a one-way clutch are provided between the outer peripheral surface of the sleeve and the inner peripheral surface of the driven pulley. Of these, support bearings
While supporting the radial load applied to the driven pulley, the relative rotation between the sleeve and the driven pulley is made free.
In addition, the one-way clutch allows the transmission of rotational force from the driven pulley to the sleeve only when the driven pulley rotates in a predetermined direction with respect to the sleeve.

The reasons for using the pulley device with a built-in one-way clutch for an alternator as described above are 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 (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 rotationally driven by the endless belt via a driven pulley, 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 driven pulley is simply fixed to the rotating shaft 3, the inner peripheral surface of the endless belt and the outer peripheral surface of the driven pulley tend to rub in both directions due to 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 with the driven pulley, causing slippage between the endless belt and the driven pulley, or shortening the life of the endless belt. Becomes The reduction in the life of the endless belt due to the friction between the outer peripheral surface of the driven pulley and the inner peripheral surface of the endless belt also occurs due to repeated acceleration and deceleration during traveling.

Therefore, by using the pulley device with a built-in one-way clutch for the alternator as the driven pulley as described above, when the running speed of the endless belt is constant or tends to increase, the driven pulley is driven from the driven pulley. The transmission of the rotational force to the rotating shaft 3 is made freely, and conversely, when the running speed of the endless belt tends to decrease, the relative rotation between the driven pulley and the rotating shaft 3 is made freely. That is, when the running speed of the endless belt tends to decrease, the rotational angular speed of the driven pulley is made slower than the rotational angular speed of the rotating shaft 3 so that the contact portion between the endless belt and the driven pulley is strong. Prevent rubbing. 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 conventional pulley apparatus with a built-in one-way clutch for an alternator as described above, each of the pulley apparatuses has a space in which a plurality of lock members constituting a one-way clutch are installed, and a one-way clutch. The space in which a plurality of rolling elements constituting a pair of support bearings are installed communicates with each other, and the lubricating grease to be sealed in each of these spaces is shared.
However, the appropriate amount of grease sealed in the space in which the plurality of lock members are installed and the space in which the plurality of rolling elements are installed are different from each other.

That is, in the case of the support bearing, the rolling contact portions between the rolling surfaces of the rolling elements and the inner and outer raceways are appropriately lubricated, and the agitation resistance of the grease is suppressed.
It is necessary to prevent the rotation resistance of the support bearing from increasing. Therefore, the appropriate amount of grease to be sealed in the space in which the rolling elements are installed is about 30% (20 to 40%) of the volume of the cavity of the space in which the rolling elements are installed. On the other hand, in the case of the one-way clutch, since the plurality of lock members rub against at least one of the inner peripheral side and the outer peripheral side at the time of overrun (unlocked), sufficient lubrication is achieved. Unless the heat treatment is performed, the amount of heat generated at the rubbed portion tends to increase. If the amount of heat generated at the rubbing portion is increased, the lubricating grease is thermally degraded at an early stage, and the durability of the one-way clutch is impaired. Therefore, it is necessary to sufficiently lubricate the rubbed portion to prevent the grease from being thermally deteriorated early. For this reason, the amount of grease sealed in the space where the lock members are installed needs to be larger than the appropriate amount of grease sealed in the space where the rolling elements are installed.

Therefore, as in the conventional structure described above, when the grease sealed in the space in which the lock members are installed and the space in which the rolling elements are installed are shared, the grease sealed in the spaces communicated with each other. Based on the amount
At least one of the one-way clutch and each of the support bearings may have the above-described problem.
In particular, if a malfunction such as poor lubrication or grease deterioration occurs in the one-way clutch, the main functions of the pulley device with a built-in one-way clutch for an alternator are impaired. For this reason, it is necessary to regulate the amount of grease sealed in the space in which the lock members are installed to an appropriate value. The pulley device with a built-in one-way clutch for an alternator of the present invention was invented in view of the above-mentioned circumstances.

[0010]

The pulley apparatus with a built-in one-way clutch for an alternator according to the present invention has a sleeve which can be externally fitted and fixed to the rotating shaft of the alternator, similarly to the conventional structures described in the above-mentioned publications. A driven pulley disposed concentrically with the sleeve around the sleeve, and provided between an axial intermediate portion of the outer peripheral surface of the sleeve and an axial intermediate portion of the inner peripheral surface of the driven pulley, and the driven pulley is attached to the sleeve. On the other hand, a one-way clutch capable of freely transmitting a rotational force between the driven pulley and the sleeve only when the sleeve tends to relatively rotate in a predetermined direction, and the sleeve at a position sandwiching the one-way clutch from both axial sides. Between the outer peripheral surface of the driven pulley and the inner peripheral surface of the driven pulley to freely rotate the sleeve and the driven pulley while supporting the radial load applied to the driven pulley. And a pair of support bearings that.
In particular, in the pulley device with a built-in one-way clutch for an alternator of the present invention, a space in which the one-way clutch is installed is provided by providing a sealing member between the one-way clutch and the two support bearings. Sealed. The space in which the one-way clutch is installed is filled with grease of 60 to 80% of the volume of the cavity of the space.

[0011]

As described above, in the case of the pulley device with a built-in one-way clutch for an alternator according to the present invention, the space in which the one-way clutch is installed is sealed by a pair of sealing members, and the space in which this one-way clutch is installed is sealed. Contains the proper amount of grease. Therefore, it is possible to sufficiently lubricate the sliding contact portion between each lock member constituting the one-way clutch and at least one of the inner circumferential side and the outer circumferential side, so that the grease is quickly thermally deteriorated. Can be prevented. Also, since an appropriate amount of grease can be sealed in the space where the rolling elements constituting the pair of support bearings are installed, it is possible to prevent problems such as an increase in rotational resistance of each of the support bearings.

[0012]

FIG. 1 shows a first embodiment of the present invention. The pulley device with a built-in one-way clutch for an alternator of the present embodiment has a sleeve 8 which can be fitted and fixed to the rotating shaft 3 of the alternator 1 (see FIG. 3). Further, a driven pulley 7 a is arranged around the sleeve 8 concentrically with the sleeve 8. A pair of support bearings 9, 9 and a roller clutch 10, which is a one-way clutch, are provided between the outer peripheral surface of the sleeve 8 and the inner peripheral surface of the driven pulley 7a.

The sleeve 8 has a cylindrical shape as a whole. The sleeve 8 is externally fitted and fixed to an end of the rotating shaft 3 of the alternator 1 and is rotatable together with the rotating shaft 3. For this reason, in the illustrated example, a screw hole 11 is formed in the inner peripheral surface of the intermediate portion of the sleeve 8, and the screw hole 11 and a male screw portion provided on the outer peripheral surface of the tip of the rotating shaft 3 can be screwed freely. And
A locking hole 12 having a hexagonal cross section is formed on the inner peripheral surface of the distal end portion of the sleeve 8.
The tip of a tool such as a hexagon wrench can be freely locked. Note that the structure in which the sleeve 8 and the rotating shaft 3 are combined so as not to rotate relative to each other may employ other structures such as spline engagement, non-circular engagement, and key engagement. Further, the outer peripheral surface of such a sleeve 8 is merely a cylindrical surface.

On the other hand, a half of the outer peripheral surface of the driven pulley 7a (the left half in FIG. 1) has a cross-sectional shape extending in the width direction, and a part of an endless belt called a poly-V belt can be freely passed over. I have. The inner peripheral surface of the driven pulley 7a is a simple cylindrical surface. Then, the sleeve 8
The roller clutch 10 is provided at an axially intermediate portion of a space existing between the outer peripheral surface of the driven pulley 7a and the inner peripheral surface of the driven pulley 7a.
The roller clutch 1 is also provided at both axial ends of this space.
0 at the position sandwiching the support bearing 9 from both sides in the axial direction.
9 are arranged respectively.

The roller clutch 10 transmits a rotational force between the driven pulley 7a and the sleeve 8 only when the driven pulley 7a tends to rotate relative to the sleeve 8 in a predetermined direction. Be free. In order to constitute such a roller clutch 10, the roller clutch inner ring 13 is externally fitted and fixed to the outer peripheral surface of the intermediate portion of the sleeve 8 by interference fit. This inner ring for roller clutch 1
Numeral 3 denotes a steel plate made of a carburized steel or the like subjected to plastic working such as press working to form a cylindrical body as a whole, and a cam surface 14 formed on an outer peripheral surface. That is, a plurality of concave portions 15, 15 called a ramp portion are formed on the outer peripheral surface of the inner race 13 for the roller clutch.
Are formed at equal intervals in the circumferential direction so that the outer peripheral surface is the cam surface 14.

On the other hand, in the inner peripheral surface of the outer ring 16 for the roller clutch fixed to the inner peripheral surface of the intermediate portion of the driven pulley 7a by interference fit, at least the axial direction in contact with the rollers 18, 18 described below. The intermediate portion is simply a cylindrical surface. The outer ring 16 for such a roller clutch is also formed by subjecting a steel plate made of carburized steel or the like to plastic working such as press working so as to be entirely formed in a cylindrical shape, and has inward flange-shaped flanges 17a and 17b at both axial ends. Is formed. One of the flanges 17a and 17b (left side in FIG. 1) is formed in advance at the time of manufacturing the outer ring 16 for the roller clutch. It has the same thickness as the part. On the other hand, the other (rightward in FIG. 1) flange portion 17b is provided inside the roller clutch outer ring 16 in the diametrical direction with rollers 18 and 18 described below.
And the clutch retainer 19 to be built in
It is thin.

A plurality of rollers 18, 18 constituting the roller clutch 10 together with the roller clutch inner ring 13 and the roller clutch outer ring 16, are provided on the roller clutch inner ring 13 and the roller clutch inner ring 1.
The clutch 3 is supported by a synthetic resin clutch retainer 19 fitted outside so as to be unable to rotate with respect to the roller 3 so as to be able to roll and slightly displace in the circumferential direction. Then, between the column provided on the clutch retainer 19 and each of the rollers 18, 18.
A spring such as a leaf spring or a synthetic resin spring integrated with the clutch retainer 19 is provided.
It is elastically pressed in the same direction with respect to the circumferential direction. or,
In the state shown in the figure, the outer diameter side portions of both axial end surfaces of the clutch retainer 19 are closely opposed to the inner side surfaces of both flange portions 17a and 17b constituting the outer race 16 for the roller clutch. The cage 19 is prevented from being displaced in the axial direction. Since the basic structure and operation of such a roller clutch 10 are well known in the related art, further detailed illustration and description will be omitted.

The support bearings 9, 9 support the radial load applied to the driven pulley 7a and allow the driven pulley 7a and the sleeve 8 to rotate relative to each other. In the case of this example, a deep groove type ball bearing is used as each of the support bearings 9 and 9. That is, each of these support bearings 9, 9 has a deep groove type outer raceway 2 on its inner peripheral surface.
0, 20 and inner races 23, 23 having deep groove inner raceways 22, 22 on their outer peripheral surfaces.
And a plurality of balls 24, 24 which are provided between the outer raceways 20, 20 and the inner raceways 22, 22 so as to freely roll, respectively.
Consisting of In addition, a pair of seal rings 26, 26, each of which is a sealing member, is attached to the locking grooves 25, 25 formed on the inner peripheral surfaces of both ends of the outer rings 21, 21, respectively.
The openings at both ends of the space 27 in which the balls 24 are placed are closed.

In each of such support bearings 9, 9, the respective outer ring 21, 21 is internally fitted and fixed to both ends of the inner peripheral surface of the driven pulley 7a by interference fit.
The outer peripheral surface 22 of the sleeve 8 is externally fitted and fixed to the outer peripheral surface of the sleeve 8 by interference fit, so that the outer peripheral surface of the sleeve 8 and the inner peripheral surface of the driven pulley 7a are assembled. In the illustrated example, the caulking portions 28, 2 are formed by plastically deforming a plurality of portions of the inner peripheral edge portions at both end surfaces of the driven pulley 7a.
The outer end surfaces of the outer races 21 (the end surfaces of the driven pulleys 7a on the outer side in the width direction) are pressed down by the caulking portions 28, 28. This prevents the outer races 25 from coming out of the driven pulley 7a. In the case of this example, the roller clutch 10 is installed at a portion between the middle portion of the inner peripheral surface of the driven pulley 7a and the middle portion of the outer peripheral surface of the sleeve 8 in a state where the support bearings 9 are assembled in this manner. Openings at both ends of the space 29 are tightly closed by the seal rings 26 on the roller clutch 10 side of the pair of seal rings 26 mounted on the support bearings 9.

Grease for lubrication is filled in spaces 27, 27 in which the balls 24, 24 constituting the support bearings 9, 9 are installed, and in a space 29 in which the roller clutch 10 is installed. . The amount of grease sealed in the spaces 27, 27 in which the balls 24, 24 are installed is about 30% (20 to 40%) of the volume of the cavity in each of the spaces 27, 27. The amount of about 30% of the volume of the hollow portion of the space 27 appropriately lubricates the rolling contact portions between the rolling surfaces of the balls 24, 24 and the inner and outer races 22, 20, and This is an appropriate amount to prevent the rotational resistance of each support bearing 9, 9 from becoming too large. If the amount is less than 20%, there is a possibility that the rolling contact portions cannot be sufficiently lubricated. On the contrary,
If the above-mentioned filling amount exceeds 40%, the stirring resistance of the grease increases, and the rotational resistance of each of the support bearings 9 increases. On the other hand, the amount of grease sealed in the space 29 in which the roller clutch 10 is installed is determined by the volume of the hollow portion of the space 29 (the inner peripheral surface of the driven pulley 7a, the outer peripheral surface of the sleeve 8 and the support bearings 9). , 9, the inner space of the annular space surrounded by the inner seal rings 26, 26, the inner race 13 for the roller clutch, the outer race 16 for the roller clutch, the plurality of rollers 18, 18, which constitute the roller clutch 10. The volume is restricted to 60 to 80% of the volume of the clutch retainer 19 and the spring (not shown). The reason is as follows.

The amount of grease sealed in the space 29 is
If the volume of the hollow portion of the space 29 is less than 60%, the amount of the grease becomes insufficient, and the amount of heat generated by the sliding contact between the members constituting the roller clutch 10 when the roller clutch 10 is overrun is large. Become.
As a result, the grease sealed in the space 29 is thermally degraded early. On the other hand, when the amount of grease sealed in the space 29 is larger than 80% of the volume of the cavity of the space 29, the support bearings 9
The air trapped in the space 29 is compressed when the support bearings 9 and 9 are pushed into the space between the both ends of the sleeve a and the both ends of the sleeve 8 (actually, the support bearings 9 and 9 are pushed one by one). The pressure in this space 29 becomes excessively high. For this reason, the seal rings 26, 26 attached to the support bearings 9, 9 form a space 29.
The grease sealed in the space 29 leaks into the spaces 27 during operation because the seal lips constituting the seal rings 26 are turned off by being pressed by the internal pressure. Create possibilities. Further, even after the support bearings 9 are assembled, when the temperature in the space 29 rises during the operation of the roller clutch 10 and the expansion amount of the grease sealed in the space 29 increases, the space The pressure inside the space increases significantly, and each of the seal lips is turned up, again causing the possibility that the grease sealed in the space 29 leaks into the spaces 27, 27. For this reason, in the case of the present invention, the amount of grease sealed in the space 29 is restricted to 60 to 80% of the volume of the cavity of the space 29.

In the case of the pulley device with a built-in one-way clutch for an alternator of the present embodiment constructed as described above, a space 29 in which the roller clutch 10 is installed, a pair of support bearings 9,
Spaces 27, 27 where the balls 24, 24 constituting the 9 are installed
Means the roller clutch 10 of the pair of seal rings 26, 26 mounted on the support bearings 9, 9, respectively.
It is partitioned by seal rings 26, 26 arranged on the side. An appropriate amount of grease is sealed in each of the spaces 29 and 27. For this reason, it is possible to prevent the grease sealed in the space 29 from being thermally deteriorated at an early stage, or to prevent inconvenience such as an increase in the rotational resistance of the support bearings 9 and 9. Therefore, it is possible to provide a high-performance and highly reliable product such as low rotational resistance.

Next, FIG. 2 shows a second embodiment of the present invention.
An example is shown. In the case of this example, the convex portion 3 projecting diametrically outward from the outer peripheral surface on the intermediate portion outer peripheral surface of the sleeve 8a.
0 is formed over the entire circumference. And, this convex part 30
A roller clutch inner ring 13 is externally fitted and fixed to the outer peripheral surface of the roller clutch by interference fit. In the case of the present embodiment having such a configuration, the roller clutch inner ring 13 is fixed to the outer peripheral surface of the convex portion 30 so as to be externally fixed to the outer peripheral surface of the convex portion 30 by interference fit. Of press-fitting (pressing stroke in the axial direction) when press-fitting by hydraulic cylinder
Can be reduced. Therefore, the efficiency of the assembling work can be improved.
Other configurations and operations are the same as those of the above-described first example.

In each of the above-described examples, the case where the low clutch 10 is used as the one-way clutch has been described. However, the present invention has been known as a one-way clutch such as a cam clutch such as a sprag clutch. The same effect can be obtained when a one-way clutch having another structure is used. Further, the pair of support bearings 9, 9 are not limited to ball bearings, and similar effects can be obtained even when roller bearings, or both roller bearings and ball bearings are employed. Further, in each of the above-described examples, the structure in which a space is provided between the end surfaces of the support bearings 9 and 9 and the end surface of the roller clutch 10 (the end surface of the outer ring 16 for the roller clutch) is shown. It is also possible to apply the present invention to a structure in which the distance between the end surfaces of the support bearings 9 and 9 and the end surface of the roller clutch 10 is reduced (narrowed) to about 0 to 0.5 mm. Further, as the outer ring 16 for the roller clutch, flange portions 17a, 17
It is also possible to adopt a cylindrical structure without b, or to omit the outer ring for the roller clutch, and to use the inner peripheral surface of the driven pulley 7a directly as the outer raceway surface of the roller clutch.

[0025]

The pulley device with a built-in one-way clutch for an alternator according to the present invention is constructed and operates as described above, so that a problem occurs in the one-way clutch and each support bearing based on the amount of grease sealed therein. Things can be prevented. Therefore, a high-performance and highly reliable product can be provided.

[Brief description of the drawings]

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

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alternator 2 Housing 3 Rotating shaft 4 Rolling bearing 5 Rotor 6 Commutator 7, 7a Followed pulley 8, 8a Sleeve 9 Support bearing 10 Roller clutch 11 Screw hole 12 Locking hole 13 Inner ring for roller clutch 14 Cam surface 15 Depression 16 Roller clutch outer ring 17a, 17b Flange 18 Roller 19 Clutch retainer 20 Outer ring track 21 Outer ring 22 Inner ring track 23 Inner ring 24 Ball 25 Locking groove 26 Seal ring 27 Space 28 Caulked portion 29 Space 30 Convex portion

Claims (1)

[Claims] 1. A sleeve which can be externally fitted and fixed to a rotating shaft of an alternator, a driven 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 periphery of the driven pulley. Provided between the driven pulley and the sleeve only when the driven pulley tends to rotate relative to the sleeve in a predetermined direction. A one-way clutch, provided between the outer peripheral surface of the sleeve and the inner peripheral surface of the driven pulley at a position sandwiching the one-way clutch from both sides in the axial direction, and supporting the radial load applied to the driven pulley with these sleeves. In a pulley device with a built-in one-way clutch for an alternator, comprising a pair of support bearings capable of freely rotating relative to a driven pulley, the one-way clutch and the two-way clutch are provided. By providing a sealing member at a portion between the support bearings, the space in which the one-way clutch is installed is sealed, and the space in which the one-way clutch is installed has a space of 60 to 80% of the volume of the cavity of this space. A pulley device with a built-in one-way clutch for alternators, characterized by containing grease.