JP2001214964A - Resin pulley - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin pulley for efficiently radiating the heat generated in a roller bearing by attaching a cover member to an outer ring as a substitute for a slinger. SOLUTION: Fitting parts 8b of a metal cover member 8 are externally fitted around the both ends of the outer ring 2 of the roller bearing and the resin pulley part 5 is integrally molded around its outer circumference.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin pulley used for an idler pulley or the like.

[0002]

2. Description of the Related Art An automobile engine uses a belt transmission mechanism such as a V-belt or a toothed belt to transmit rotation to an alternator or the like. This belt transmission mechanism uses an idler pulley to give the belt an appropriate tension. Recently, resin pulleys have been increasingly used as the idler pulleys in order to reduce the size and weight of automobile parts and reduce costs.

FIGS. 2 and 3 show examples of the structure of a conventional resin pulley used for the above idler pulley. This resin pulley uses a radial ball bearing in which a plurality of steel balls 3 are arranged between an inner ring 1 and an outer ring 2. The inner ring 1 is formed in a boss shape by forming a stepped or tapered mounting hole in the inner diameter of an annular member made of a steel material, and has a raceway surface of a steel ball 3 formed on an outer peripheral surface. The outer ring 2 is a ring-shaped steel material which is arranged at intervals on the outer peripheral side of the inner ring 1, and has a raceway surface of a steel ball 3 formed on an inner peripheral surface. The steel balls 3 are steel balls inserted on the raceway surface between the inner ring 1 and the outer race 2, and are supported by the retainer 4 and are arranged at equal angular intervals in the circumferential direction of the raceway surface. . Therefore, the inner ring 1 is fixed and the outer ring 2 is fixed.
Is rotated, the plurality of steel balls 3 roll on the raceway surfaces of the inner ring 1 and the outer ring 2, so that the rotation of the outer ring 2 can be smoothly supported only by the rolling friction at this time.

[0004] On the outer periphery of the outer ring 2 of the radial ball bearing,
A pulley portion 5 made of phenol resin or the like is formed. The pulley portion 5 is formed integrally by covering the outer peripheral portion of the outer ring 2 by injection molding on the outer peripheral portion of the outer ring 2.
A V-pulley having a groove is formed.

[0005] A seal member 6 is fitted between the inner ring 1 and the outer ring 2 of the radial ball bearing from both sides, and a slinger 7 is further attached to the outside thereof, so that water is applied to the raceway surface on which the steel balls 3 roll. And dust etc. are prevented from entering. The sealing material 6 is a ring-shaped rubber seal reinforced with an iron plate. The outer peripheral portion is fixed to the outer ring 2 and the inner peripheral end piece is slid in contact with the outer peripheral surface of the inner ring 1 so that water, dust, etc. Is kept out. Slinger 7
A steel plate having a U-shaped cross section is formed in a ring shape with the U-shaped opening facing inward, and the outer peripheral surface is fixed to both ends of the inner peripheral surface of the pulley portion 5. In addition, these slinger 7
The two inner peripheral ends of the U-shape reach very close to the outer peripheral surface of the inner ring 1. Therefore, by these slinger 7,
Most of the water, dust, and the like that try to enter the inside can be eliminated.

[0006]

If the pulley portion is made of metal, even if heat is generated in the radial ball bearing by rotation, the heat is transmitted from the outer race through the metal material having good heat conductivity. And efficiently radiate heat from the large pulley into the atmosphere. However, in the case of a resin pulley, a phenol resin or the like having poor heat conductivity of the pulley portion 5 serves as a heat insulating material, so that heat is easily stored in the radial ball bearing.

[0007] For this reason, the conventional resin pulley has a problem that the temperature of the radial ball bearing is easily increased, so that the seal and grease are deteriorated to cause poor lubrication and the bearing may be seized.

The present invention has been made in order to cope with such a situation. By attaching a metal cover member which is fitted to the outer peripheral surface of the outer ring instead of the slinger, the heat generated by the rolling bearing can be efficiently reduced. It is an object of the present invention to provide a resin pulley that can radiate heat well.

[0009]

According to a first aspect of the present invention, there is provided a resin pulley in which a resin pulley portion is integrally formed on the outer periphery of an outer ring of a metal rolling bearing. Therefore, two metal cover members projecting cylindrical fitting portions that are sufficiently shorter than half the width of the outer peripheral surface of the outer ring allow the respective fitting portions to extend from both ends to the outer peripheral surface of the outer ring. The fitting portion of the cover member is covered with the resin pulley portion together with the outer peripheral surface of the outer ring by being fitted.

According to the first aspect of the present invention, since the fitting portion of the metal cover member is fitted on the outer peripheral surface of the outer ring, heat generated by the rotation of the rolling bearing is conducted to the fitting portion of the cover member. As a result, heat can be efficiently radiated from the cover. Further, since the cover portion of the cover member covers between the outer ring and the inner ring of the rolling bearing, it is possible to prevent water and dust from entering the inside.

The invention according to claim 2 is characterized in that the ring-shaped cover portion of the cover member has an inner diameter slightly larger than the outer peripheral surface of the inner race of the rolling bearing.

According to the second aspect of the invention, since the inner peripheral end of the cover portion of the cover member approaches the inner ring, it is possible to more reliably prevent water and dust from entering between the outer ring and the inner ring.

[0013]

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

FIG. 1 shows an embodiment of the present invention and is a partially enlarged longitudinal sectional view of a resin pulley.

In this embodiment, a resin pulley used for an idler pulley similar to the conventional example shown in FIGS. 2 and 3 will be described. The radial ball bearing of this resin pulley has the same configuration as that of the conventional example, and a steel ball 3 supported by a retainer 4 is disposed on a raceway surface between an inner ring 1 and an outer ring 2.
A seal member 6 is fitted between the inner ring 1 and the outer ring 2 from both sides.

Cover members 8 are attached to both ends of the outer ring 2 of the radial ball bearing. The cover member 8 is a metal component in which a cylindrical fitting portion 8 b projects from the outer peripheral edge of the ring-shaped cover portion 8 a, and the inner diameter of the fitting portion 8 b is fitted to the outer diameter of the outer ring 2. It is a size that can be combined. The cylindrical length of the fitting portion 8b is
Is much shorter than half the width of The inner diameter of the cover portion 8a is slightly larger than the outer peripheral surface of the inner ring 1.

The two cover members 8 having the above structure are mounted by fitting fitting portions 8b to the outer peripheral surface of the outer race 2 from both ends of the radial ball bearing. At this time, since the fitting portion 8b is shorter than the width of the outer race 2, a sufficient space is generated between the facing end portions. Also, the cover 8
Since the inner peripheral end of “a” approaches the outer peripheral surface of the inner ring 1, most of the radial ball bearing between the inner ring 1 and the outer ring 2 is covered by the cover portion 8 a.

On the outer periphery of the outer ring 2 of the radial ball bearing,
A pulley part 5 is formed. The pulley portion 5 is a V pulley having a plurality of circumferential V-grooves formed on an outer peripheral portion made of a phenol resin or the like. And this pulley part 5 is the outer ring 2
Is formed integrally by injection molding so as to cover the outer peripheral surface of the cover member 8 and the fitting portion 8b of the cover member 8. In addition, a PPS resin (polyphenylene sulfide) or the like can be used for the pulley portion 5 in addition to the phenol resin. Further, a reinforcing material such as an inorganic or organic fiber or powder is added to the resin material serving as the base resin, and in some cases, a thermal conductive material such as alumina or aluminum hydroxide is added.

The resin pulley having the above structure is used as an idler pulley of a belt transmission mechanism by fixing an inner ring 1 of a radial ball bearing to a tension adjusting portion. In this case, when heat is generated in the radial ball bearing by the rotation of the resin pulley, the heat is transmitted from the outer race 2 to the fitting portion 8 of the cover member 8.
b to the cover 8a. Then, the cover 8a rotates in the air, so that heat can be efficiently released to the outside.

Therefore, according to the present embodiment, the heat generated in the radial ball bearing can be efficiently radiated from the metal cover member 8, so that deterioration of the seal and grease and occurrence of poor lubrication can be prevented. The life of the pulley can be extended. Moreover, since there is a sufficient space between the fitting portions 8b of the two cover members 8 fitted to both ends of the outer ring 2, the injection pressure when the pulley portion 5 is injection-molded is reduced by the fitting pressure 8b. And creep can be prevented from occurring. Further, since the pulley portion 5 covers not only the fitting portion 8b but also the outer peripheral surface of the outer ring 2 exposed between these ends, the outer ring 2 and the cover member 8 can be surely integrated. Further, these cover members 8 are provided with cover portions 8a.
Since it has a simple shape having an L-shaped cross section composed of the fitting portion 8b and the fitting portion 8b, the workability is good and the attachment to the outer ring 2 is easy.

The cover portion 8a of the cover member 8
Covers most of the space between the inner ring 1 and the outer ring 2 of the radial ball bearing, so that water, dust and the like can be prevented from entering the inside and can be used as a substitute for a slinger. However, since there is a slight gap between the cover portion 8a and the outer peripheral surface of the inner ring 1, water, dust, and the like may enter therethrough.
However, the water, dust, and the like can be reliably prevented from further entering the inside by the sealing material 6.

In the above embodiment, the case where the pulley portion 5 is a V pulley having a plurality of V grooves has been described. However, the pulley portion 5 may be a V pulley having one V groove.
It may be a toothed pulley. In the above embodiment,
Although the resin pulley provided with a radial ball bearing has been described, a rolling bearing provided with a needle bearing can also be used.

[0023]

As is apparent from the above description, according to the resin pulley of the present invention, the heat generated by the rotation of the rolling bearing is efficiently transferred from the cover portion through the metal cover member which fits on the outer peripheral surface of the outer race. Since heat is radiated well, there is no danger that the bearing will seize due to abnormal lubrication due to abnormal rise in temperature. Further, since the cover portion of the cover member covers between the outer ring and the inner ring of the rolling bearing instead of the slinger, it is possible to prevent water and dust from entering the inside.

[Brief description of the drawings]

FIG. 1, showing an embodiment of the present invention, is a partially enlarged longitudinal sectional view of a resin pulley.

FIG. 2 shows a conventional example and is a longitudinal sectional view of a resin pulley.

FIG. 3 is a partially enlarged longitudinal sectional view of a resin pulley, showing a conventional example.

[Description of Signs] 1 inner ring 2 outer ring 5 pulley section 8 cover member 8a cover section 8b fitting section

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Nori Yamakawa 3-5-8 Minamisenba, Chuo-ku, Osaka-shi, Osaka Inside Koyo Seiko Co., Ltd. (72) Kenji Nakamura 3-5-minamisenba, Chuo-ku, Osaka-shi, Osaka No. 8 F-term in Koyo Seiko Co., Ltd. (reference) 3J031 BA08 BC02 BC05 BC10 CA03

Claims (2)

[Claims] 1. A resin pulley in which a resin pulley portion is integrally formed on an outer periphery of an outer ring of a metal rolling bearing, wherein a resin pulley portion is formed from an outer peripheral edge of a ring plate-shaped cover portion to a half of a width of an outer peripheral surface of the outer ring. Also, two cover members made of metal having a sufficiently short cylindrical fitting portion project from each other so that the fitting portions are fitted to the outer peripheral surface of the outer race from both end sides, thereby fitting these cover members. A resin pulley whose portion is covered by a resin pulley together with the outer peripheral surface of the outer ring. 2. The resin pulley according to claim 1, wherein the ring-shaped cover portion of the cover member has an inner diameter slightly larger than the outer peripheral surface of the inner race of the rolling bearing.