JP2002188709A - Pulley unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulley unit with high durability by enhancing a lubricating performance. SOLUTION: This pulley unit is constituted by installing one-way clutch 4 and a plain bearing 5 so as to adjoin in the shaft direction in facing circular spaces of concentrically arranged two inside and outside rings 2, 3, and fixing the plain bearing 5 to the ring 3 so as to slide and contact to the ring 2 of the two rings 2, 3. Lubricant rooms 13, 14 are installed in at least one of the sliding contact surfaces of the plain bearing 5 with the ring 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a pulley unit having a one-way clutch.

[0002]

2. Description of the Related Art A pulley unit having a one-way clutch can be mounted on a driven device driven by a crankshaft of an engine of an automobile or the like via a belt. In addition, as a driven device, for example, a compressor for an air conditioner of an automobile, a water pump,
An alternator, a cooling fan, etc. are mentioned.

In this type of conventional pulley unit, a rolling bearing or a sliding bearing is provided on at least one side of a one-way clutch in order to bear a radial load acting between two inner and outer rings. Is known.

In particular, as an inexpensive pulley unit, a structurally simple sliding bearing has been used.

[0005]

However, in the prior art, the sliding contact surfaces of the sliding bearing and one of the rings that are in sliding contact with the sliding bearing are opposing surfaces along the circumferential direction. The lubrication between the sliding bearing and one of the ring members is performed only by the lubricant existing between the surfaces.

[0006] Therefore, as the amount of lubricant existing between the opposed surfaces decreases as time elapses due to use, poor lubrication occurs, thereby increasing the temperature and abrasion at the sliding contact points, resulting in poor durability. There was a problem such as lowering.

The present invention has been made in view of the above circumstances, and has as its object to provide a highly durable pulley unit with improved lubricating performance.

[0008]

According to a first aspect of the present invention, there is provided a pulley unit in which a one-way clutch and a slide bearing are axially adjacent to each other in an opposed annular space of two concentrically arranged inner and outer rings. Wherein the sliding bearing is a pulley unit fixed to the other ring body in a form of sliding contact with one of the two ring bodies, wherein the sliding bearing and the one ring A feature is that a lubricant reservoir is formed on at least one of the sliding contact surfaces with the body.

According to the first aspect of the present invention, since the lubricant reservoir is formed on at least one of the sliding contact surfaces between the slide bearing and one of the ring members, the sliding contact surface of the lubricant is formed. The reduced amount can be replenished from the lubricant reservoir.

According to a second aspect of the present invention, in the pulley unit according to the first aspect, the lubricant reservoir has at least a sliding contact surface between the sliding bearing and the one annular body. A pulley unit characterized by forming a concave groove on one side.

According to the second aspect of the present invention, since the lubricant is stored in the groove, the sliding surface of the lubricant from the lubricant reservoir formed as a groove along the sliding surface is provided. There is an advantage that the replenishment can be smoothly performed, and the lubricant can be automatically replenished without providing a special lubricant replenishing device.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view showing a plain bearing, and FIG.
3 is a longitudinal sectional side view showing the pulley unit 1, FIG. 3 is a sectional view taken along line AA in FIG. 2, and FIG. 4 is a sectional view taken along line BB in FIG.

The illustrated pulley unit 1 has a pulley 2, a hollow shaft 3, a one-way clutch 4, and two sliding bearings 5,5.

The pulley 2 is rotatably driven by, for example, a crankshaft of an automobile engine via a belt 6, and has a wavy groove on the outer periphery of which the belt 6 is wound.

The hollow shaft 3 is inserted through the inner periphery of the pulley 2 and is fixed to an input shaft of an accessory of an automobile engine (for example, a rotor of an alternator), not shown.

Here, the pulley 2 forms an outer ring body,
The hollow shaft 3 constitutes an inner ring.

The one-way clutch 4 includes a pulley 2 and a hollow shaft 3.
The inner ring 7 and the outer ring 8, the annular retainer 9, the plurality of rollers 1
0, an elliptical coil spring 11 is provided. The inner ring 7
It is fitted to the hollow shaft 3 by press-fitting, and a flat key-like cam surface 7a is provided at eight circumferential positions on the outer peripheral surface. The outer race 8 is fitted into the pulley 2 by press fitting, and has an inner peripheral surface formed in a cylindrical shape. The retainer 9 is disposed in an annular space facing the inner ring 7 and the outer ring 8, and has a protrusion 9 c provided on the retainer 9 and the inner ring 7.
The outer case is positioned in the circumferential direction and the axial direction with respect to the inner race 7 by the slits 7b provided in the outer case. Several places around the circumference of the retainer 9, that is, the cam surface 7 of the inner ring 7
In a region corresponding to a, a pocket 9a penetrating inward and outward in the radial direction is provided. The rollers 10 are stored in the respective pockets 9a of the retainer 9 with the circumferential rolling range being regulated one by one. The coil spring 11 is mounted on a projection 9 b projecting from the inner wall surface of each pocket 9 a of the retainer 9, and forms a roller 10 on the narrow side of a wedge-shaped space formed by the cam surface 7 a and the inner peripheral surface of the outer ring 8. (Lock side).

The two plain bearings 5 and 5 are interposed one by one on both sides in the axial direction of the annular space facing the pulley 2 and the hollow shaft 3, and each of them is made of a general plain bearing material (for example, copper alloy). , Resin, etc.) in an annular shape. These slide bearings 5 and 5 are press-fitted and fixed to the inner ring 7. On the other hand, the outer peripheral surfaces of the slide bearings 5 and 5 and the inner peripheral surface of the outer ring 8 facing the outer peripheral surface are sliding surfaces. Small-diameter steps 5a, 5a are provided on the outer shoulders of the outer peripheral surfaces of the slide bearings 5, 5, and a ring-shaped seal made of only an elastic material is provided for the small-diameter steps 5a, 5a. 12, 12 are mounted in a state of having a reduced diameter elasticity. The small-diameter step portions 5a, 5
At the shaft end of a, annular protrusions 5b, 5b are provided radially outward to prevent the seals 12, 12 from coming off in the axial direction.

As shown, the seals 12, 12 have conical lips 12a, 12a on the outer periphery of the annular portion.
The lips 12a, 12a
Are pressed against the inner peripheral surface of the pulley 2 in a bent state.

Next, the characteristic configuration of the present invention will be described. A plurality of grooves 13 and 14 are formed at equal intervals around the rotation axis P on the inner peripheral surface of the outer ring 8 which is a sliding surface facing the outer peripheral surface of each of the slide bearings 5 and 5. . FIG. 1 shows only one of the pair of slide bearings 5 and the hollow shaft 3.

Each of the grooves 13 and 14 is provided with a rotation axis P
Are formed at an angle to the sliding bearing 5,
The concave groove 13 on the outer peripheral surface of the outer ring 5 and the concave groove 14 on the inner peripheral surface of the outer ring 8 are formed so as to intersect each other when viewed in the radial direction. Grease as a lubricant is stored in these concave grooves 13 and 14, and forms a lubricant pool.

Therefore, when the sliding bearings 5, 5 and the outer ring 8 slide, the grease stored in the concave grooves 13, 14 between the sliding surfaces is diffused to provide a lubricating surface. ing. Since the lubricant grease is stored in the concave grooves 13 and 14, the lubricant is replenished from the concave grooves 13 and 14 to the sliding surfaces in response to the decrease in the lubricant on the sliding surfaces. As a result, the lubrication performance can be maintained satisfactorily for a long time, and the durability can be increased.

In the above embodiment, the groove as a lubricant reservoir is formed obliquely in the radial direction with respect to the rotation axis direction. However, the groove may be formed parallel to the rotation axis direction. Alternatively, the groove may be provided such that the groove formed in parallel in this way is connected to a groove orthogonal to the groove in a radial direction.

In the above-described embodiment, the lubricant groove is formed by forming the concave grooves on the sliding surfaces of each other. For example, as shown in FIG. Alternatively, the inner peripheral surface of the outer ring 8 may be knurled to form a large number of concave grooves 15. FIG. 5 shows only one of the pair of slide bearings 5 and the hollow shaft 3.

With this configuration, since the thin grooves 15 are formed in an oblique lattice pattern, the lubricant can be replenished in a uniform state with respect to the sliding contact surface. Further, the lubricant pool can be easily formed by knurling, and the number of grooves can be relatively large, so that the lubricant pool can be increased. In the knurling, not the diagonal lattice but the rotation axis P
May be lattice grooves intersecting vertically and horizontally, and a large number of grooves parallel to the rotation axis P may be arranged in the circumferential direction.

Further, in the above embodiment, the lubricant reservoir is formed on both the outer peripheral surface of the slide bearing and the inner peripheral surface of one of the rings, but one of those surfaces is provided. Only the lubricant reservoir may be formed.

Further, in the above embodiment, the outer ring side is used as a sliding surface for the sliding bearing, and the inner ring side is used as the fixed side of the sliding bearing. However, the sliding bearing is fixed to the outer ring side, May be configured as the sliding surface.

[0029]

According to the first or second aspect of the present invention, the lubricant reservoir is formed on at least one of the sliding contact surface between the sliding bearing and one of the ring members. In this case, the amount reduced from the space between the sliding surfaces can be replenished from the lubricant pool, and the lubricant can be prevented from being consumed from the sliding surface, and as a result, the lubricating performance for the sliding bearing can be improved Thus, the durability can be improved.

In particular, according to the structure of the second aspect of the present invention, since the lubricant is stored in the concave groove, the lubricant slides from the lubricant pool formed as a groove along the sliding contact surface. There is an advantage that the replenishment to the contact surface can be smoothly performed, the lubricant can be automatically replenished without providing a special lubricant replenishing device, and the durability can be improved with a simple structure.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a sliding bearing according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional side view showing an upper half portion of an example of a pulley unit according to the present invention.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a sectional view taken along line BB in FIG. 2;

FIG. 5 is a perspective view showing a main part of a sliding bearing according to another embodiment of the present invention.

[Description of Signs] 1 Pulley unit 2 Pulley (ring) 3 Hollow shaft (ring) 4 One-way clutch 5 Sliding bearing 6 Belt

Claims (2)

[Claims] 1. A one-way clutch and a slide bearing are disposed axially adjacent to each other in an opposed annular space between two inner and outer rings arranged concentrically, and the slide bearing is formed of the two rings. A pulley unit fixed to the other ring member in a form of sliding contact with one of the ring members, wherein at least one of the sliding contact surfaces of the slide bearing and the one ring member has a lubricant reservoir. Forming a pulley unit. 2. The pulley unit according to claim 1, wherein the lubricant reservoir forms a concave groove on at least one of sliding surfaces of the sliding bearing and the one ring body. A pulley unit.