JP2000087988A - Anti-creep device for rolling bearings - Google Patents

Abstract

(57) [Summary] To ensure the effect of preventing rotation of outer ring 2 with respect to housing 1. An eccentric groove is formed on an outer peripheral surface of an outer ring, and an outer peripheral surface of an eccentric ring fitted in the eccentric groove is frictionally engaged with an inner peripheral surface of a housing. In this state, the frictional force acting on the contact surface between the inner peripheral surface of the housing 1 and the outer peripheral surface 12 of the eccentric ring 4 causes the bottom surface 5 of the eccentric groove 3 and the eccentric ring 4
The friction coefficient of each of these peripheral surfaces is regulated so as to be larger than the frictional force acting on the contact surface with the inner peripheral surface 11. This prevents the eccentric ring 4 from rotating together with the outer ring 2 inside the housing 1, and ensures the effect of preventing the rotation of the outer ring 2 with respect to the housing 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a creep preventing device for a rolling bearing, in which an outer ring of a rolling bearing incorporated in a rotation supporting portion of various auxiliary devices for an automobile, such as an alternator or a compressor for a car air conditioner, has an outer ring formed inside a housing. Used to prevent rotation.

[0002]

2. Description of the Related Art In many cases, various auxiliary machines for automobiles incorporate a rolling bearing for supporting a rotary shaft inside an aluminum alloy housing. In the assembled state, the outer race constituting the rolling bearing is internally fitted and fixed inside the housing by interference fit. Incidentally, the coefficient of thermal expansion of the aluminum alloy forming the housing is larger than the coefficient of thermal expansion of the bearing steel forming the outer ring of the rolling bearing. Because of this,
If no measures are taken, the interference of the outer ring with the housing decreases (or loses) when the temperature rises, so that the outer ring rotates inside the housing, so-called creep occurs, and rotation by the rolling bearings occurs. Rattling occurs in the support portion. In addition, the inner peripheral surface of the housing is worn with the rotation of the outer ring, so that the rattling is gradually increased.

In order to prevent the rotation of the outer ring inside the housing, which causes such inconveniences, conventionally, for example, Japanese Utility Model Laid-Open Publication No. 58-108626 and 63-17351.
No. 9, JP-A-1-85527, JP-A 2-1
JP-A-0771, JP-A-4-75227, JP-A-7-229522, and the like have known a rolling bearing creep preventing device. Each of the rolling bearing creep preventing devices described in each of these publications forms an eccentric groove on the outer peripheral surface of the outer ring, with the center axis of the bottom surface of the eccentric groove eccentric with respect to the center axis of the outer ring. ing.
An eccentric ring formed entirely of an elastic synthetic resin in a partially annular shape and having the center axis of its inner peripheral surface and the center axis of its outer peripheral surface eccentric to each other is fitted inside the eccentric groove. ing. When the rolling bearing is fitted and fixed inside the housing, the eccentric ring is fitted inside the inner peripheral surface of the housing.

The coefficient of thermal expansion of the synthetic resin forming the eccentric ring is greater than the coefficient of thermal expansion of the aluminum alloy forming the housing. For this reason, even if the interference of the outer ring to the housing tends to decrease as the temperature rises, the thickness of the eccentric ring in the diameter direction increases, thereby compensating for the decrease of the interference. Further, since the bottom surface of the eccentric groove and the inner peripheral surface of the eccentric ring are eccentric with respect to the outer peripheral surfaces of the outer ring and the eccentric ring, the outer ring and the eccentric ring do not rotate relative to each other. That is, when the outer ring rotates inside the housing during the operation of the rolling bearing, the inner peripheral surface of the housing and the bottom surface of the eccentric groove are formed when the outer ring slightly rotates inside the housing. A part of the eccentric ring (a part with a large diametrical width) penetrates into a part between the two (a part with a small diametrical width between these two surfaces), so that a so-called wedge effect is obtained. . As a result of obtaining such a wedge effect, the outer ring is prevented from further rotating. Therefore, even when the temperature rises, the outer ring made of the bearing steel does not rotate inside the aluminum alloy housing.

[0005]

In the case of a conventionally known anti-creep device for a rolling bearing, the slip between the outer peripheral surface of the eccentric ring and the inner peripheral surface of the housing is prevented by the eccentric ring with respect to the housing. Is achieved only by the frictional force associated with the press-fitting. Therefore, the frictional force acting on the contact surface (fitting surface) between the outer peripheral surface of these eccentric rings and the inner peripheral surface of the housing is increased by the contact surface (fitting surface) between the inner peripheral surface of this eccentric ring and the bottom surface of the eccentric groove. If it is smaller than the friction force acting on
When the outer ring tries to rotate inside the housing,
The outer ring and the eccentric ring may rotate together inside the housing. When the outer ring and the eccentric ring rotate together in this way, the wedge effect described above cannot be obtained, so that the outer ring cannot be prevented from rotating with respect to the housing. The fact that the magnitudes of the frictional forces acting on the respective contact surfaces are different means that the surface roughnesses of the respective peripheral surfaces that are in contact with each other are different, or the slidability of the material constituting each of the peripheral surfaces ( It is also caused by differences in the surface slipperiness).

On the other hand, the outer diameter of the eccentric ring is increased in order to increase the frictional force accompanying the press-fitting of the eccentric ring into the housing, and the amount by which the outer peripheral surface of the eccentric ring projects from the outer peripheral surface of the outer ring is increased. More can be considered. However, when such a structure is adopted, it is not preferable because not only the work of pushing the eccentric ring into the housing but also the roundness of the outer ring is adversely affected. In view of the above circumstances, the anti-creep device for a rolling bearing of the present invention prevents the outer ring and the eccentric ring from rotating together inside the housing, so that the outer ring rotates with respect to the housing. It has been invented to ensure that a wedge effect for preventing the problem can be obtained.

[0007]

A creep preventing device for a rolling bearing according to the present invention is provided on an inner peripheral surface of an outer ring like a creep preventing device for a rolling bearing described in the above-mentioned publications and the like. An outer ring having a raceway, an inner ring having an inner raceway on an outer peripheral surface, a plurality of rolling elements rotatably provided between the outer raceway and the inner raceway, and a recess formed in the outer peripheral surface of the outer raceway from the outer peripheral surface. Eccentric groove formed in a state in which the center axis of the bottom surface is eccentric with respect to the center axis of the outer ring, and an entire ring is formed of an elastic material. An eccentric ring in which the central axis of the outer peripheral surface is eccentric to each other, and a housing having a cylindrical inner peripheral surface are provided. Then, with the eccentric ring fitted inside the eccentric groove, the eccentric ring is internally fitted and fixed to the inner peripheral surface of the housing. In particular, in the anti-creep device for a rolling bearing according to the present invention, the frictional force acting on the contact surface between the outer peripheral surface of the eccentric ring and the inner peripheral surface of the housing is applied to the inner peripheral surface of the eccentric ring and the eccentric surface. It is larger than the frictional force acting on the contact surface with the bottom of the groove.

The friction force acting on the contact surface between the outer peripheral surface of the eccentric ring and the inner peripheral surface of the housing is determined by the friction force acting on the contact surface between the inner peripheral surface of the eccentric ring and the bottom surface of the eccentric groove. Specifically, the following methods (1) to (4) can be adopted. By coating the inner peripheral surface of the eccentric ring with a lubricant, the friction coefficient (static friction coefficient) of the inner peripheral surface of the eccentric ring is made smaller than the friction coefficient of the outer peripheral surface. In this case, the lubricant is preferably oil, grease, solid lubricant, or the like. More preferably, a solution in which the solid lubricant is dispersed in an organic solvent together with a thermosetting resin is applied to the inner periphery of the eccentric ring. The surface is coated with a spray or the like. By coating the outer peripheral surface of the eccentric ring with a friction agent, the friction coefficient of the outer peripheral surface of the eccentric ring is made larger than the friction coefficient of the inner peripheral surface. In this case, the friction agent is not particularly limited as long as it increases the friction coefficient of the outer peripheral surface of the eccentric ring. As such a friction agent, for example, a rubber material such as epoxy, silicone rubber, nitrile rubber, fluorine rubber, a tacky adhesive,
Ceramic coating or the like is desirable, and more preferably, epoxy, silicone rubber, or the like is used. The coefficient of friction at the bottom of the eccentric groove is reduced. In order to reduce the friction coefficient of the bottom of the eccentric groove in this way, for example,
This bottom surface is polished, wrapped, etc. to reduce the surface roughness of this bottom surface, or oil,
Apply lubricant such as grease or solid lubricant. The coefficient of friction of the inner peripheral surface of the housing is increased.
In order to increase the friction coefficient of the inner peripheral surface of the housing in this way, for example, the inner peripheral surface is roughened to increase the surface roughness of the inner peripheral surface. Is coated with a friction agent. The friction agent is not particularly limited as long as it increases the friction coefficient of the inner peripheral surface of the housing. As such a friction agent, for example, a rubber material such as an epoxy, a silicone rubber, a nitrile rubber, and a fluorine rubber, a tacky adhesive, and a ceramic coating are preferable. By configuring the inner diameter side portion and the outer diameter side portion of the eccentric ring with materials having different surface slidabilities,
The friction coefficient of the outer peripheral surface of the eccentric ring is made larger than the friction coefficient of the inner peripheral surface. For example, the eccentric ring is formed of a metal material having a bimetal structure of copper and iron, or the outer diameter side portion of the eccentric ring is formed of a polymer material, and the inner diameter side portion also contains a solid lubricant. For example, a method using a high-molecular material to be used can be considered. In the latter case, the same kind of material or different kinds of materials may be used for the polymer material as the base material in the outer diameter side portion and the inner diameter side portion. For example, a material in which the inner diameter side portion is formed of a polymer material containing a solid lubricant and the outer diameter side portion is formed of a rubber material having a large surface friction coefficient is suitable.

[0009] Each of the above methods (1) to (4) may be used alone, for example, a combination of two methods, such as, and, a, a, and a, and a combination of three or more methods. Can also be adopted. The eccentric ring can be made of any material as long as it has elasticity. However, the ring-shaped eccentric ring is preferably made of a metal material or a synthetic resin material. The ring is desirably made by injection molding a synthetic resin material. Among them, it is preferable to use a partially annular eccentric ring, and more preferably, to use a partially annular eccentric ring made by injection molding a synthetic resin material. More preferably, an elastically deforming portion is provided on a part of the eccentric ring so as to protrude outward in the diameter direction of the eccentric ring, and an intermediate portion of the elastically deforming portion has a circular arc concentric with the outer peripheral surface of the eccentric ring. There is an arc-shaped abutting portion which is long in the circumferential direction and abuts substantially evenly on the inner circumferential surface of the housing over the entire length thereof.

[0010]

In the anti-creep device for a rolling bearing according to the present invention constructed as described above, the frictional force acting on the contact surface between the outer peripheral surface of the eccentric ring and the inner peripheral surface of the housing is determined by the inner peripheral surface of the eccentric ring. The friction force acting on the contact surface between the eccentric groove and the bottom of the eccentric groove is made larger. Therefore, when the outer ring tries to rotate inside the housing, it is possible to prevent the outer ring and the eccentric ring from rotating together inside the housing. For this reason, when the outer ring tries to rotate inside the housing,
A so-called wedge effect is obtained in which a part of the eccentric ring bites into a part between the inner peripheral surface of the housing and the bottom surface of the eccentric groove, and rotation of the outer ring with respect to the housing can be reliably prevented.

[0011]

1 to 3 show an example of an embodiment of the present invention. A rolling bearing 6 is fitted and fixed inside the housing 1 made of an aluminum alloy and having a cylindrical inner peripheral surface. The rolling bearing 6 is rotatably provided between the outer race 2 having an outer raceway 7 on an inner peripheral surface, an inner race 9 having an inner raceway 8 on an outer peripheral surface, and the outer raceway 7 and the inner raceway 8. A plurality of rolling elements 10 and 10 are provided.
An eccentric groove 3 is formed on the outer peripheral surface of the outer ring 2 so as to be recessed from the outer peripheral surface. The bottom surface 5 of the eccentric groove 3
Is eccentric with respect to the center axis of the outer ring 2.
An eccentric ring 4 is fitted in the eccentric groove 3. In the case of this example, as shown in FIG. 3, the eccentric ring 4 is made of an elastic synthetic resin and is entirely formed in a partially annular shape.
In the eccentric ring 4, the center axis of the inner peripheral surface 11 and the center axis of the outer peripheral surface 12 are eccentric to each other. The direction in which the central axes of these two peripheral surfaces are eccentric is a direction in which the central axis of the inner peripheral surface 11 is deviated toward the discontinuous portion 13 of the eccentric ring 4 with respect to the central axis of the outer peripheral surface 12. Therefore, the thickness of the eccentric ring 4 in the diameter direction is largest at the center in the circumferential direction, and becomes gradually smaller toward both ends in the circumferential direction.

In order to assemble the anti-creep device for a rolling bearing according to the present invention including the rolling bearing 6 and the eccentric ring 4 as described above, first, the eccentric groove 3 on the outer peripheral surface of the outer ring 2 constituting the rolling bearing 6 is formed. The eccentric ring 4 is fitted inside the. At this time, the eccentric direction of these eccentric grooves 3 and the eccentric ring 4
Of the eccentric ring 4 and the outer peripheral surface of the outer ring 2 in the diametrical direction are made substantially uniform over the entire circumference. When the eccentric ring 4 is fitted inside the eccentric groove 3 in this way, the eccentric ring 4 is fitted together with the outer ring 2 on the inner peripheral surface of the housing 1 by interference fitting. In particular, in the case of this example, the creep preventing device for the rolling bearing is assembled in such a manner that it acts on the contact surface (fitting surface) between the outer peripheral surface 12 of the eccentric ring 4 and the inner peripheral surface of the housing 1. The frictional force is made larger than the frictional force acting on the contact surface (fitting surface) between the inner peripheral surface 11 of the eccentric ring 4 and the bottom surface 5 of the eccentric groove 3. That is, in order to regulate the frictional force acting on each of these contact surfaces as described above, for example, the inner peripheral surface 1 of the eccentric ring 4 is used.
1 is coated with a lubricant such as grease (in other words, the lubricant is interposed between the inner peripheral surface 11 of the eccentric ring 4 and the bottom surface 5 of the eccentric groove 3).

In the case of the anti-creep device for a rolling bearing according to the present embodiment having the above-described structure, the interference of the outer ring 2 with respect to the housing 1 is reduced as the temperature rises.
When it is attempted to rotate inside the housing 1 and the eccentric ring 4, when the outer ring 2 has been rotated by a certain angle α (see FIG. 2) from the initial assembly position, a part of the eccentric ring 4 (A part with a large width in the diameter direction)
Are the inner peripheral surface of the housing 1 and the bottom surface 5 of the eccentric groove 3.
(A portion having a small width in the diametric direction between these two surfaces) between the two surfaces, so-called wedge effect is obtained. As a result of obtaining such a wedge effect, the outer ring 2 is prevented from further rotating, and the rotation of the outer ring 2 with respect to the housing 1 can be prevented.

In particular, in the case of the anti-creep device for a rolling bearing according to the present embodiment, the frictional force acting on the contact surface between the outer peripheral surface 12 of the eccentric ring 4 and the inner peripheral surface of the housing 1 is applied to the inside of the eccentric ring 4. The frictional force acting on the contact surface between the peripheral surface 11 and the bottom surface 5 of the eccentric groove 3 is set larger. For this reason, when the outer ring 2 tries to rotate inside the housing 1,
It is possible to prevent the outer ring 2 and the eccentric ring 4 from rotating together inside the housing 1. Therefore, when the outer ring 2 tries to rotate inside the housing 1, the wedge effect described above is reliably obtained, and the rotation of the outer ring 2 with respect to the housing 1 can be reliably prevented.

[0015]

Next, the frictional force acting on the contact surface between the outer peripheral surface of the eccentric ring and the inner peripheral surface of the housing, which is a feature of the present invention, will be described with reference to the inner peripheral surface of the eccentric ring and the bottom surface of the eccentric groove. A specific method for making the friction force larger than the frictional force acting on the contact surface will be described based on the following first to sixth embodiments. In each of the embodiments, the outer ring 2 (FIGS. 1 and 2) constituting the rolling bearing 6 used had an outer diameter of 72 mm.

(First Embodiment) In this embodiment, an eccentric ring 4a as shown in FIG. 4 is employed. This eccentric ring 4a
Is made of an elastic synthetic resin and is entirely formed in an annular shape, and the center axis of its inner peripheral surface 11a and the center axis of its outer peripheral surface 12a are eccentric to each other. In the case of this embodiment, the inner diameter side portion of the eccentric ring 4a is made of polyphenylene sulfide resin (PPS) containing 30% of polytetrafluoroethylene resin (PTFE), and the outer diameter side portion is made of glass fiber. It was composed of 30% blended PPS. The friction coefficient of the outer peripheral surface of the eccentric ring 4a is calculated from the friction coefficient of the inner peripheral surface on the basis of the difference in the slidability on the surfaces of the synthetic resin material constituting both the inner diameter side and the outer diameter side. Was also enlarged.

In the case of this embodiment, the eccentric groove 3 (FIG. 1)
As the eccentric ring 4a to be fitted in 2) is employed, the eccentric ring 4a is formed by injection molding, and the eccentric ring 4a is formed simultaneously with the eccentric ring 4a.
Was fitted in the eccentric groove 3. That is, in order to form the eccentric ring 4a in this manner, first, the inner diameter side portion (PTFE) is formed.
Is mixed with 30% of PPS) on the bottom surface 5 of the eccentric groove 3.
(FIGS. 1 and 2) are injection-molded around the inner diameter side part, and then the outer diameter side part (glass fiber is 30%
Compounded PPS) was also formed by injection molding. In the present embodiment, the thickness of the inner diameter side portion in the diameter direction is set to 1.5 mm over the entire circumference, and the outer circumference surface of the outer diameter side portion is the outer ring 2 over the entire circumference (FIGS. 1-2). The thickness of the outer diameter side portion in the diametric direction was regulated so as to protrude from the outer peripheral surface by 0.02 mm. The width of the eccentric ring 4a in the axial direction (the front and back direction in FIG. 4) is not particularly limited, but is 5 mm in this embodiment.

(Second Embodiment) In the present embodiment, FIG.
The eccentric ring 4 having a partially annular shape shown in FIG. In the case of the present embodiment, the eccentric ring 4 is formed by press forming a cold rolled steel plate (SPCC). Further, a molybdenum disulfide coating was formed on the inner peripheral surface 11 of the eccentric ring 4 by sputtering to a thickness of 1 μm. Further, the outer peripheral surface 12 of the eccentric ring 4 was subjected to a sandblasting treatment of 80 mesh to deteriorate the surface roughness of the outer peripheral surface 12. Thereby, the friction coefficient of the outer peripheral surface 12 was made larger than the friction coefficient of the inner peripheral surface 11. In this embodiment, the width of the eccentric ring 4 in the axial direction is set to 2.5 mm.
And

In the case where an annular ring is used as the eccentric ring 4 as described above, the material constituting the eccentric ring 4 can be selectively used based on design considerations according to the application. For example, in the case where the ring-shaped eccentric ring 4 is made of a synthetic resin material, the glass fibers may be 10 to 4 pieces.
PPS containing 0% by volume has a heat-resistant temperature of 200 ° C. or more and has excellent mechanical strength, and thus can be preferably used.
In the case of PPS reinforced with such a glass fiber,
When the content of this glass fiber is less than 10% by volume,
The strength improvement effect due to the incorporation of glass fibers is weak and the glass fibers are easily crushed. Conversely, if the glass fiber content exceeds 40% by volume, the elasticity is too low and the glass fibers are easily broken. Therefore, PPS containing glass fiber as described above
A glass fiber having a glass fiber content of 10 to 40% by volume, more preferably 20 to 30% by volume is suitable from the viewpoint of securing strength and reducing costs. Examples of the material constituting the above-mentioned ring-shaped eccentric ring 4 include PPS, resin-based materials such as polyamide 11, polyamide 46, polyamide 66, polybutylene terephthalate (PBT), modified polyphenylene oxide (PPO), and PBT. Rubber materials such as elastomers and polyamide elastomers can also be used. Further, like PPS, each of these materials is
It can also be reinforced with 40% by volume of glass fibers.

For example, as in the case of the metal eccentric ring 4 described above, a molybdenum disulfide film having a thickness of 1 μm is formed on the inner peripheral surface 11 of the synthetic resin eccentric ring 4 formed by injection molding. In addition to the above, the outer peripheral surface 12 of the eccentric ring 4 may be subjected to sandblasting of 80 mesh to deteriorate the surface roughness of the outer peripheral surface 12. Also in this case, the friction coefficient of the outer peripheral surface 12 can be made larger than the friction coefficient of the inner peripheral surface 11.

(Third Embodiment) Also in the case of the present embodiment, the above-mentioned annular eccentric ring 4 shown in FIG. 3 is employed. In the case of this embodiment, the eccentric ring 4 is made of glass fiber of 10%.
The polyamide resin contained is made by injection molding. The inner peripheral surface 11 is coated with molybdenum disulfide, and the outer peripheral surface 12 is coated with a synthetic rubber-based adhesive (synthetic rubber + acrylic rubber) by coating drying. . Thereby, the friction coefficient of the outer peripheral surface 12 was made larger than the friction coefficient of the inner peripheral surface 11. In this embodiment, the eccentric ring 4 is used.
Was 5 mm in the axial direction.

(Fourth Embodiment) In this embodiment, an eccentric ring 4b as shown in FIG. 5 is employed. This eccentric ring 4b
Is provided with elastically deforming portions 14, 14 projecting outward in the diametrical direction at a part of the eccentric ring 4 having a ring shape shown in FIG. 3 (in this embodiment, at three places in the circumferential direction). Become. Arc-shaped abutting portions 15 are provided in the middle of the elastically deforming portions 14. These arc-shaped contact portions 15, 1
The outer peripheral surfaces 17, 17 of the eccentric ring 4b are concentric with the outer peripheral surface 12 of the eccentric ring 4b and are long in the circumferential direction. Each of the elastic deformation portions 14, 14 connects the arc-shaped contact portions 15, 15 and the main body of the eccentric ring 4 b to each of the arc-shaped contact portions 1.
Bent portions 16 provided at both ends in the circumferential direction of 5, 15;
16 are continuous. Therefore, when the eccentric ring 4b is fitted in the housing 1 (FIGS. 1 and 2), the outer peripheral surfaces 17, 17 of the arc-shaped abutting portions 15, 15 respectively correspond to the inner peripheral surface of the housing 1 and the entire length thereof. Contact almost evenly over

The eccentric ring 4b as described above is formed by injection molding PPS containing 30% glass fiber. In the case of this embodiment, the outer peripheral surface 1 of the eccentric ring 4b including the outer peripheral surfaces 17 and 17 of the arc-shaped contact portions 15 and 15 respectively.
2, the silicone rubber dispersed in dimethyl ether,
It was coated to a thickness of 10 μm using a spray. Furthermore, after this coating, the solvent was evaporated by heating to 80 ° C., and the outer peripheral surface 12 was given tackiness. In addition, such coating is applied to the entire outer peripheral surface 12 of the eccentric ring 4b as in this embodiment,
It may be applied only to the outer peripheral surfaces 17, 17 of the respective elastic deformation portions 14, 14. With the above configuration, the friction coefficient of the outer peripheral surface 12 is made larger than the friction coefficient of the inner peripheral surface 11. In this embodiment, the width of the eccentric ring 4b in the axial direction was 5 mm.

In the case of this embodiment, the eccentric ring 4b
The elastically deformable portion 14 is elastically crushed between the inner peripheral surface of the housing 1 and the bottom surface 5 of the eccentric groove 3 in a state in which the outer ring 2 and the outer ring 2 are press-fitted and fitted into the inner peripheral surface of the housing 1.
As a result, the outer peripheral surface 17 of the arc-shaped contact portion 15 that forms the intermediate portion of the elastic deformation portion 14 elastically contacts the inner peripheral surface of the housing 1. Therefore, this housing 1
Even if there is some error between the diameter of the inner peripheral surface of the eccentric groove 3 and the diameter of the bottom surface 5 of the eccentric groove 3, the effect of preventing the eccentric ring 4b from slipping on the inner peripheral surface of the housing 1 is sufficient. Can be demonstrated in. The number of the elastic deformation portions 14 formed on the eccentric ring 4b is not particularly limited as long as there is no problem in fixing the eccentric ring 4b inside the housing 1.

(Fifth Embodiment) In this embodiment, the eccentric ring shown in FIG. 3 was employed as the eccentric ring, and this eccentric ring was formed of PPS containing 40% of glass fiber. As shown in FIG. 6 (a), a number of narrow grooves 18 are formed on the outer peripheral surface 12 of the eccentric ring in the axial direction (the front and back directions in FIG. 6). It was provided at equal intervals throughout. Furthermore, the outer peripheral surface 12 of this eccentric ring
An epoxy resin (coating agent 19) dissolved in ethyl cellosolve was heated at 90 ° C. for 1 hour using a curing agent to coat the substrate with a thickness of 20 μm. Thereby, the friction coefficient of the outer peripheral surface 12 of the eccentric ring was made larger than the friction coefficient of the inner peripheral surface 11. In this embodiment, the width of the eccentric ring in the axial direction was 5 mm.

In this embodiment, since a large number of narrow grooves 18 are formed on the outer peripheral surface 12, a so-called anchor effect can be obtained at each of these narrow grooves 18, 18, and the outer peripheral surface is formed. 12 can be sufficiently prevented from falling off (peeling). For example, when the eccentric ring of this embodiment is press-fitted inside the housing 1, even if an excessive press-fit load is applied to the eccentric ring, the coating agent 19 may fall off the outer peripheral surface 12 of the eccentric ring. Can be effectively prevented.

The narrow grooves 18 can be easily formed at the same time as the injection molding of the eccentric ring by forming a projecting piece in the injection molding die. Each of the narrow grooves 18, 18 is provided with an annular eccentric ring 4 shown in FIG.
a, or may be provided on the entire surface or a part of the surface of the eccentric rings 4, 4b of the partially annular shape shown in FIGS. For example, as shown in FIG. 6B, it is provided only on the inner peripheral surface 12 of the eccentric ring, or as shown in FIG.
Is provided only on the outer peripheral surface 17 of the main body, or as shown in FIG.
It may be provided only on the inner peripheral surface 11 of the eccentric ring provided with the elastic deformation portion 14, or may be provided on both the inner and outer peripheral surfaces of the eccentric ring. That is, it is preferable that each of the narrow grooves 18 is appropriately formed on a portion of the surface of the eccentric ring which is covered with the coating agent 20 such as a lubricant or a frictional agent so that the above-described anchor effect can be obtained.

(Sixth Embodiment) In this embodiment, FIG.
Eccentric ring having the characteristics as shown in FIG.
An eccentric ring having a partially annular shape having the following is adopted. In the case of the present embodiment, this eccentric ring was formed by injection molding PPS containing 40% of glass fibers. The inner peripheral surface 11 of the eccentric ring is spray-coated with a dispersion of PTFE in an organic solvent in which polyamideimide is dissolved with pyrrolidone, and then thermally cured at 200 ° C. for one hour to form an inner peripheral surface. In No. 11, a coating layer having a thickness of 20 μm was formed. Further, the outer peripheral surface 12 of the eccentric ring was coated with an epoxy resin by spraying, and then thermally cured at 90 ° C. to form a coating layer having a thickness of 20 μm on the outer peripheral surface 12. Thereby, the friction coefficient of the outer peripheral surface 12 of the eccentric ring was made larger than the friction coefficient of the inner peripheral surface 11. In this embodiment, the width of the eccentric ring in the axial direction was 5 mm.

Further, in the present embodiment, the inner peripheral surface of the aluminum alloy housing 1 is subjected to a sandblasting treatment of 80 mesh to deteriorate the surface roughness of the inner peripheral surface to thereby reduce the friction of the inner peripheral surface. The coefficient has been increased. After grinding the bottom surface 5 of the eccentric groove 3, the bottom surface 5 is further polished with # 1000 (grain size 1000) emery paper.
By reducing the surface roughness of the bottom surface 5, the friction coefficient of the bottom surface 5 was reduced.

Table 1 below shows the results of experiments conducted by the present inventor to confirm the effects of the first to sixth embodiments. In this experiment, at a temperature of 120 ° C., an eccentric ring fitted in the eccentric groove 3 (FIGS. 1 and 2) of the outer race 2 was press-fitted and fitted inside the housing 1 (FIGS. 1 and 2).
A torque (rotational force) was applied to the outer ring 2. Then, the magnitude of the torque required to rotate the outer ring 2 inside the housing 1 was measured. Table 1 above
In Comparative Example 1, the result of the first embodiment in which the outer diameter side portion and the inner diameter side portion of the eccentric ring are made of the same material (PPS having the same glass fiber blending amount) in the first embodiment,
Similarly, Comparative Example 2 shows the results of an example in which the outer peripheral surface is not coated with the epoxy resin in the fifth embodiment.

[0031]

[Table 1]

[0032]

The creep preventing device for a rolling bearing according to the present invention is constructed and operated as described above, so that it is possible to prevent the outer ring and the eccentric ring from rotating together inside the housing. Therefore, a wedge effect for preventing the outer ring from rotating inside the housing is reliably obtained, and a highly reliable product can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of the present invention.

FIG. 2 is a view from the left of FIG.

FIG. 3 is a view taken from the left of FIG. 1 and shows only the eccentric ring.

FIG. 4 shows the eccentric ring employed in the first embodiment, FIG.
FIG.

FIG. 5 shows the eccentric ring employed in the fourth embodiment, FIG.
FIG.

FIG. 6 shows an eccentric ring employed in the fifth to sixth embodiments.
Partial side view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Outer ring 3 Eccentric groove 4, 4a, 4b Eccentric ring 5 Bottom surface 6 Rolling bearing 7 Outer ring track 8 Inner ring track 9 Inner ring 10 Rolling element 11, 11a Inner peripheral surface 12, 12a Outer peripheral surface 13 Discontinuous part 14 Elastic deformation part 15 Arc-shaped contact portion 16 Bent portion 17 Outer peripheral surface 18 Narrow groove 19 Coating agent 20 Coating agent

Continued on the front page F term (reference) 3J017 AA06 AA10 CA06 DA02 3J101 AA02 AA32 AA42 AA52 AA62 BA54 BA56 BA77 DA05 DA14 EA02 EA31 EA33 EA76 EA80 FA35 FA60 GA24 GA29

Claims (1)

[Claims] 1. An outer ring having an outer raceway on an inner peripheral surface, an inner racer having an inner raceway on an outer peripheral surface, a plurality of rolling elements rotatably provided between the outer raceway and the inner raceway, and the outer raceway An eccentric groove formed in a state recessed into the outer peripheral surface of the outer peripheral surface from the outer peripheral surface and with the center axis of the bottom surface eccentric with respect to the central axis of the outer ring; An eccentric ring having a central axis of its inner peripheral surface and a central axis of its outer peripheral surface eccentric to each other, and a housing having a cylindrical inner peripheral surface, wherein the eccentric ring is fitted inside the eccentric groove. In a creep preventing device for a rolling bearing, in which the eccentric ring is internally fitted and fixed to the inner peripheral surface of the housing, the contact surface between the outer peripheral surface of the eccentric ring and the inner peripheral surface of the housing is fixed. The working friction force is applied to the inner peripheral surface of the eccentric ring and the eccentricity. A creep preventing device for a rolling bearing, wherein the frictional force is greater than a frictional force acting on a contact surface with a bottom surface of a groove.