JP3698928B2 - Pulley unit - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pulley unit including a one-way clutch. The pulley unit is used, for example, as a crank pulley of an engine such as an automobile or a pulley of an auxiliary machine (such as an air conditioner compressor, a water pump, an alternator, a cooling fan) installed in the automobile.
[0002]
[Prior art]
A pulley unit used in a conventional crank pulley is shown in FIG. In the figure, 81 is a shaft body, 82 is a pulley, 83 is a one-way clutch, 84 and 84 are plain bearings, and 85 and 86 are seals.
[0003]
In this pulley unit, a rotating shaft such as a crankshaft is attached to the shaft body 81, a belt is wound around the pulley 82, and the one-way clutch 83 absorbs rotational fluctuations of the crankshaft to suppress uneven rotation of the pulley 82. It is like that. Further, damper masses 87 and 88 for damping torsional vibration and bending vibration of the crankshaft are attached to the shaft body 81.
[0004]
The one-way clutch 83 and the slide bearings 84 and 84 are fitted and fixed to the shaft body 81 by press fitting, and the pulley 82 is positioned with respect to the one-way clutch 83 and the slide bearings 84 and 84. Yes. The pulley 82 is positioned by positioning the one-way clutch 83 and the slide bearings 84, 84 on the inner peripheral surface of the pulley 82 in a radially inward direction, and a lid that is screwed to the opening end of the pulley 82. 89, and is clamped from the axial direction.
[0005]
[Problems to be solved by the invention]
By the way, the inventor of the present application diligently studied from various viewpoints in order to eliminate the waste of the configuration of the pulley unit, and came to think that the slide bearing 84 and the cage of the one-way clutch 83 could be coupled. It was.
[0006]
However, for the slide bearing 84, the slide guide surface cannot be simply made narrow, although it depends on the required load bearing capacity. There is room for improvement here.
[0007]
In view of such circumstances, an object of the present invention is to eliminate waste in the configuration of a pulley unit.
[0008]
[Means for Solving the Problems]
In the pulley unit according to the first aspect of the present invention, a one-way clutch is disposed in opposed annular spaces of two inner and outer rings arranged concentrically, and the two-way clutch is disposed on both axial sides of the one-way clutch. A sliding bearing that bears a radial load acting between two annular bodies is arranged, and the one-way clutch is arranged through an annular space concentrically with an inner ring having cam surfaces at several circumferential points and an inner ring. An outer ring that is externally mounted, a plurality of rollers that are arranged in a wedge-shaped space formed between the outer ring and each cam surface of the inner ring, each being arranged so as to be able to roll in the circumferential direction, and a wedge for each roller. A plurality of elastic members that are individually pressed to the narrow side of the shaped space, and each elastic member is individually held in a state where the elastic members are individually matched and abutted on a region extending over adjacent cam surfaces in the circumferential direction of the inner ring The circumferential rolling range of each roller is regulated. And a plurality of separator, the two sliding bearing, which is externally secured by press fitting to the inner ring member for guiding sliding the inner peripheral surface of the outer ring, annular protrusion on the outer diameter side Is formed, and the axial end portion of the separator is sandwiched from the radial direction between the inner peripheral surface of the ring- shaped convex portion and the outer peripheral surface of the inner ring of the one-way clutch .
[0009]
A pulley unit according to a second aspect of the present invention is such that the outer ring body of the first aspect and the outer ring of the one-way clutch are integrally formed.
[0010]
In short, in the present invention, for the one-way clutch, a conventionally known annular retainer is separated into a plurality of separators in the circumferential direction, and this separator is positioned by two slide bearings. It becomes possible to reduce the extravagant of the cage element and to reduce the weight. In addition, since the slide bearing is provided with a ring-shaped projection that allows the slide bearing to enter the inside of the one-way clutch, the slide guide surface of the slide bearing can be made even if the fitting portion of the slide bearing with the inner ring is made as narrow as possible. It will be as wide as possible.
[0011]
In the invention of claim 2, since the outer ring body and the outer ring of the one-way clutch are integrally formed, the configuration can be further simplified and the radial dimension can be reduced.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
The details of the present invention will be described based on embodiments shown in the drawings.
[0013]
1 to 5 show an embodiment of the present invention. 1 is a longitudinal sectional view of a pulley unit, FIG. 2 is a sectional view taken along line (2)-(2) in FIG. 1, FIG. 3 is a perspective view of a one-way clutch, and FIG. 4 is a one-way clutch. FIG. 5 is a perspective view showing a part of the separator of the one-way clutch and a plain bearing separately.
[0014]
The illustrated pulley unit A is used as a crank pulley of an automobile engine, and includes a hub 1 as an inner ring, a pulley 2 as an outer ring, a one-way clutch 3, and slide bearings 4, 4. And have.
[0015]
The hub 1 is directly or indirectly fixed to a crankshaft of an automobile engine (not shown). Damper masses 5 and 6 for damping torsional vibration and bending vibration of the crankshaft are attached to the hub 1.
[0016]
The pulley 2 is concentrically packaged with respect to the hub 1, and a wave-like groove around which a belt B for transmitting the rotational power of the crankshaft to the auxiliary machine of the automobile engine is wound on the outer periphery thereof. Is formed.
[0017]
The one-way clutch 3 is interposed in the axial center of the opposed annular space between the hub 1 and the pulley 2, and includes an inner ring 10, a plurality of rollers 11, a plurality of elliptical coil springs 12, and a plurality of separators. 13 and the pulley 2 is used as an outer ring.
[0018]
The plain bearings 4 and 4 are arranged one by one on both sides in the axial direction of the one-way clutch 3 in the opposed annular space between the hub 1 and the pulley 2, and are fitted and fixed to the hub 1 by press fitting. It is set as the form which slides and guides the inner peripheral surface of this. These slide bearings 4 and 4 are made of a general slide bearing material (for example, a synthetic resin material having lubricity, a copper-based metal material, etc.), or an iron-based metal material such as carbon steel for machine structures. May be.
[0019]
This embodiment is characterized in that an annular cage generally known in the related art in the one-way clutch 3 is divided into a plurality of separators 13 and will be described below.
[0020]
The inner ring 10 is externally fitted to the hub 1 by press-fitting. The inner ring 10 has a flat key shape for forming a wedge-shaped space with the inner peripheral surface of the pulley 2 at several circumferential positions on the outer peripheral surface. The cam surface 10a is provided.
[0021]
The rollers 11 are arranged so as to be able to roll in the circumferential direction one by one in each of the wedge-shaped spaces formed between the cam surface 10a of the inner ring 10 and the inner peripheral surface of the pulley 2.
[0022]
The coil spring 12 individually presses each roller 11 to the narrow side (lock side) of the wedge-shaped space.
[0023]
The separator 13 controls the circumferential rolling range of the roller 11 and holds the coil spring 12. The separator 13 is applied to the angular portion between the cam surfaces 10 a adjacent in the circumferential direction on the outer periphery of the inner ring 10. The two bearings 4 and 4 are positioned and restrained in the axial direction and the radial direction. The separator 13 is made of a synthetic resin material having a substantially rectangular shape in plan view, and has an outer surface formed in a partial arc shape having a required radius of curvature, and an inner surface conforming to and abutting an angular portion between adjacent cam surfaces 10a of the inner ring 10. It is made into a shape. In the separator 13, a projection 13 a to which the coil spring 12 is fitted and mounted is provided on one end surface that is narrow in plan view, and a step portion 13 b is provided on the outer side shoulders of the two side surfaces that are wide in plan view. , 13b are provided. Note that a minute convex portion 13c for preventing the coil spring 12 from coming off is provided on the outer surface of the projection 13a.
[0024]
The slide bearings 4 and 4 are provided with ring-shaped convex portions 4b and 4b that bulge in one axial direction in the outer diameter side region of one surface of the annular plate portions 4a and 4a, and the upper half section is formed in an approximately inverted L shape. Has been. The annular plate portions 4 a and 4 a are in contact with the inner ring 10 and the outer end surface in the axial direction of the separator 13 so as to restrict the axial displacement of the separator 13. The ring-shaped convex portions 4 b and 4 b hold the separator 13 in the radial direction with the inner ring 10 by being locked to the step portions 13 b and 13 b of the separator 13 so as to restrict the radial displacement of the separator 13. The end surfaces of the ring-shaped convex portions 4b and 4b are slidably contacted with the end surfaces of the rollers 11 so as to prevent the rollers 11 from skewing.
[0025]
By the way, a flange portion 2a extending inward in the radial direction is integrally provided at one end in the axial direction on the inner peripheral surface of the pulley 2, and at the opening end on the other end side in the axial direction on the inner peripheral surface of the pulley 2. The lid 7 is fixed by press-fitting.
[0026]
The pulley 2 is attached to the hub 1 by clamping the one-way clutch 3 and the slide bearings 4, 4 fixed to the hub 1 from the axial direction by the flange portion 2 a of the pulley 2 and the closing lid 7. In contrast, it is positioned in the axial direction.
[0027]
In addition, diameter-increasing stepped portions 2b and 7a are provided on the inner periphery of the flange portion 2a and the inner periphery of the closing lid 7, and seals 8 and 8 are fitted and attached to the enlarged-diameter stepped portions 2b and 7a. ing. The seals 8 and 8 are generally of a known configuration that is mounted on a rolling bearing. An elastic body such as rubber is attached to an annular cored bar, and the outer periphery of the hub 1 is used as a part of the elastic body. It is the structure which provided the lip slidably contacted with the surface.
[0028]
Next, the operation of the pulley unit A configured as described above will be described.
[0029]
The pulley unit A here can absorb the rotational fluctuation of the crankshaft connected to the hub 1. Normally, the rotational speed of the crankshaft of an automobile engine varies with torque fluctuations, and the pulley 2 is synchronized with the hub 1 by switching the one-way clutch 3 between a locked state and a free state according to the rotational fluctuations. Rotation fluctuations of the pulley 2 are suppressed by rotating or by a phenomenon that rotates due to the rotational inertia force of the pulley 2 itself.
[0030]
In short, when the rotation speed of the crankshaft and the hub 1 becomes relatively higher than that of the pulley 2, the roller 11 of the one-way clutch 3 is rolled to the narrow side of the wedge-shaped space and is locked. The pulley 2 and the pulley 2 are integrally rotated. However, when the rotation speed of the hub 1 is relatively slower than that of the pulley 2, the rollers 11 of the one-way clutch 3 are rolled to the wide side of the wedge-shaped space and become free. As a result, the pulley 2 is rotated only by the rotational inertia force. By such an operation, the rotation fluctuation of the pulley 2 can be suppressed.
[0031]
The pulley unit A described above has a structure in which the roller 11 and the coil spring 12 of the one-way clutch 3 are divided into a plurality of separators 13 without using an annular retainer as in the conventional example. The weight of the cage element can be reduced and the weight can be reduced. Further, since the slide bearings 4 and 4 are substantially L-shaped in the upper half, even if the fitting portion of the slide bearings 4 and 4 with respect to the hub 1 is made narrow to reduce the axial dimension, the pulley The sliding guide surface with respect to 2 can be made as wide as possible, and as a result, sufficient load bearing capacity can be secured.
[0032]
In addition, in the above-described embodiment, a screw hole for screwing the lid is formed in the pulley 2 as in the conventional example by fixing the lid 7 to the opening end of the pulley 2 by caulking. Therefore, the thickness of the pulley 2 can be reduced, the radial dimension of the entire pulley unit A can be reduced, and weight reduction can be achieved. Furthermore, in the above embodiment, since the seal 8 is mounted on the inner periphery of the flange portion 2a of the pulley 2, the axial dimension is larger than when a seal is installed outside the flange portion as in the conventional example. Can be shortened.
[0033]
In addition, this invention is not limited only to the said embodiment, Various application and deformation | transformation can be considered.
(1) The one-way clutch 3 in the above embodiment has a form in which the outer ring is integrated with the pulley 2. However, the outer ring may be provided separately from the pulley 2. Moreover, in the said embodiment, about the coil spring 13 of the one way clutch 3, various leaf | plate springs, elastic pieces, etc. can be substituted.
(2) In the above embodiment, an example is given in which the flange 2a is provided integrally with the pulley 2, but without providing this flange 2a, a circumferential groove is provided in the pulley 2, and the circumferential groove What attached the retaining ring, such as what is called a circlip, is also contained in this invention.
(3) About the seal 8 in the said embodiment, although not shown in figure, the seal of various well-known structures can be used.
[0034]
【The invention's effect】
In the inventions of claims 1 and 2, since the cage element in the one-way clutch is devised, the weight can be reduced, and the slide bearing is devised to position the cage element. Even if the sliding bearing fitting part with the inner ring is made as narrow as possible to reduce the occupied space, the sliding guide surface of the sliding bearing can be made as wide as possible to ensure sufficient load bearing capacity. It became so. In this way, it is possible to eliminate the waste of the configuration while maintaining the performance of the entire pulley unit.
[0035]
In the invention of claim 2, since the outer ring and the outer ring of the one-way clutch are integrally formed, the configuration can be further simplified and the radial dimension can be reduced.
[Brief description of the drawings]
1 is a longitudinal sectional view of a pulley unit according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line (2)-(2) in FIG. 1. FIG. 3 is a perspective view of a one-way clutch. FIG. 5 is a perspective view showing a one-way clutch separator and a slide bearing separately. FIG. 6 is a longitudinal sectional view of a conventional pulley unit.
A Pulley unit 1 Hub 2 Pulley 2a Pulley flange 3 One-way clutch 10 One-way clutch inner ring 11 One-way clutch roller 12 One-way clutch coil spring 13 One-way clutch separator 4 Slide bearing 4a Annular plate portion of the slide bearing 4b Ring-shaped convex part of plain bearing

Claims (2)

A one-way clutch is disposed in the opposite annular space between the two inner and outer rings arranged concentrically, and a radial load acting between the two rings is applied to both axial sides of the one-way clutch. A pulley unit in which a sliding bearing is disposed,
The one-way clutch has an inner ring having cam surfaces at several places around the circumference;
An outer ring that is concentrically arranged with respect to the inner ring through an annular space;
A plurality of rollers disposed one by one in a wedge-shaped space formed between the outer ring and each cam surface of the inner ring so as to be capable of rolling in the circumferential direction;
A plurality of elastic members that individually press each roller against the narrow side of the wedge-shaped space;
A plurality of separators that individually hold the respective elastic members in a state of being matched and abutted in regions extending over adjacent cam surfaces in the circumferential direction of the inner ring and restrict the circumferential rolling range of the rollers. Have
The both slide bearings are fitted and fixed to the inner ring body by press-fitting to slide the inner peripheral surface of the outer ring, and a ring-shaped convex portion is formed on the outer diameter side thereof. that the inner peripheral surface of the part and the inner ring of the outer circumferential surface of the one-way clutch Soo clamping the axial end portion of the separator in the radial direction, pulley unit, characterized in that. The pulley unit of claim 1,
The pulley unit, wherein the outer ring body and the outer ring of the one-way clutch are integrally formed.

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