WO2022118882A1 - Solid-lubricated rolling bearing - Google Patents

Abstract

The present invention provides a solid-lubricated rolling bearing configured such that, even when a solid lubricant located between a rolling element and a rolling element has worn, the circumferential positions of the rolling elements do not deviate, so that the inertial force of the rolling elements is unlikely to act on the solid lubricant. In a solid-lubricated rolling bearing including an inner ring (3), an outer ring (2), multiple rolling elements (4), and at least one solid lubricant (7) disposed between a rolling element (4) and a rolling element (4), a retainer (5) for separating the rolling elements (4) in the circumferential direction is provided. The solid-lubricated rolling bearing is configured such that: the retainer (5) has a ring section (5a) and comb teeth sections (5b) that extend in the axial direction from the ring section (5a) and separate the rolling elements; the solid lubricant (7) is located on the inner diameter side or the outer diameter side of the comb teeth sections (5b) of the retainer (5); and projections (8) projecting on the opposite side from the solid lubricant (7) are provided on contact surfaces of the comb teeth sections (5b) of the retainer (5), said contact surfaces contacting the rolling elements (4).

Description

Solid lubricated rolling bearings

The present invention relates to a solid lubricated rolling bearing that is lubricated by a solid lubricant arranged between rolling elements.

Solid lubricated rolling bearings are used in high temperature atmospheres and vacuum atmospheres where grease or lubricating oil cannot be used as a lubricant.

As a solid lubrication rolling bearing of this type, conventionally, one in which a separator formed of a solid lubricant is arranged between adjacent rolling elements is described in Patent Document 1 and Patent Document 2. In both configurations, a solid lubricant is interposed between adjacent rolling elements, and the solid lubricant slides on the rolling elements and raceway rings, so that the lubricant is transferred to the mating parts or lubricating powder is generated to generate bearings. The inside is lubricated.

Japanese Patent No. 62754333 Japanese Patent No. 3550689

By the way, in these conventional solid-lubricated rolling bearings, since the solid lubricant serves as a separator between the rolling elements, the position of the rolling elements in the circumferential direction becomes biased as the solid lubricant wears. This may occur and the rotational runout accuracy of the bearing may deteriorate.

In addition, since the inertial force of the rolling element acts on the solid lubricant, the solid lubricant may be excessively worn and the life of the bearing may be shortened.

Therefore, in the present invention, even if the solid lubricant located between the rolling elements wears, the position in the circumferential direction of the rolling elements is not biased, and the inertial force of the rolling elements acts on the solid lubricant. It is intended to provide a solid lubricated rolling bearing having a difficult structure.

In order to solve the above problems, the present invention presents a rolling element in a solid lubricated rolling bearing in which an inner ring, an outer ring, a plurality of rolling elements, and at least one solid lubricant are arranged between the rolling elements. This cage consists of an annular portion and a comb tooth portion that extends axially from the annular portion and separates the rolling element, and the solid lubricant is used as the comb of the cage. It is located on the inner diameter side or the outer diameter side of the tooth portion, and adopts a configuration in which a protrusion protruding to the opposite side of the solid lubricant is provided on the contact surface of the comb tooth portion of the cage with the rolling element.

By adopting such a configuration, the position of the rolling element in the circumferential direction is determined by the position of the pocket between the comb teeth of the cage. Therefore, even if the solid lubricant is worn, the rolling elements are not biased and the rotational runout accuracy of the bearing is not deteriorated. Further, since the interference force between the rolling element and the solid lubricant is generated not by the rolling element but by the inertial force of the solid lubricant having a small mass, the wear rate of the solid lubricant is alleviated.

Further, by providing a protrusion protruding on the opposite side of the solid lubricant on the contact surface of the comb tooth portion of the cage with the rolling element, the contact surface can be made less likely to be worn and solid lubrication can be achieved. The volume of the agent can be increased, and the life of the agent can be extended.

By the way, in order to increase the volume of the solid lubricant, it is necessary to reduce the volume of the cage. In particular, in the present invention in which the solid lubricant is placed inside or outside the comb teeth of the cage, the comb teeth need to be thinned, which can cause premature wear of the contact surface. .. Therefore, in the present invention, by providing a protrusion on the comb tooth portion of the cage to expand the contact surface with the rolling element, the contact surface pressure between the two is relaxed and the wear of the contact surface is suppressed. I am trying to do it.

Further, by making the width dimension W1 of the protrusion smaller than the width dimension W2 of the raceway surface, it is possible to provide a solid lubricated rolling bearing in which the protrusion does not easily interfere with the raceway ring and the rotation is smooth. That is, by providing the protrusion at a position corresponding to the concave shape of the raceway surface, a large clearance between the protrusion and the raceway ring can be obtained.

Further, the volume of the solid lubricant can be further increased by making the outer diameter dimension formed by connecting the vertices of the outer diameter side protrusions of the cage larger than the outer ring inner diameter dimension. That is, by making the protrusion internal in the concave shape of the outer ring raceway surface, the diameter dimension of the comb tooth portion of the cage can be increased, and the space on the inner diameter side of the comb tooth portion can be increased. When the cage is inserted into the outer ring, the protrusion is made inside the raceway surface while the comb tooth portion is elastically deformed toward the inner diameter side.

Further, the volume of the solid lubricant can be further increased by making the inner diameter dimension formed by connecting the vertices of the protrusions provided on the inner diameter side of the cage smaller than the inner ring outer diameter dimension. That is, by making the protrusion internal in the concave shape of the inner ring raceway surface, the diameter dimension of the comb tooth portion of the cage can be reduced, and the space on the outer diameter side of the comb tooth portion can be increased. When the cage is inserted into the inner ring, the protrusion is embedded in the raceway surface while the comb portion is elastically deformed to the outer diameter side.

In addition, the solid lubricant is formed in a comb shape similar to that of the cage, and the comb tooth portion of the solid lubricant is inserted or externally inserted into or externally inserted into the comb tooth portion of the cage to extend the life of the solid lubricant, which in turn is solid. The life of the lubricated rolling bearing can be extended. That is, by connecting and integrating the solid lubricant with the annular portion, the behavior of the solid lubricant can be stabilized, and the sticking to the outer ring and the cage due to the centrifugal force can be suppressed, and the wear of the solid lubricant can be suppressed. Can be suppressed.

Further, the configuration of the solid lubricant can be further strengthened by configuring the annular portion of the cage and the annular portion of the solid lubricant to be located on opposite sides of the rolling element in the axial direction. That is, compared to the configuration in which the cage and the annular portion of the lubricant are arranged on the same side, the annular portion of the solid lubricant can be configured to be thicker, and the annular portion of the solid lubricant is less likely to break. ..

According to the present invention, it is possible to provide a solid lubricated rolling bearing in which the rolling element is not biased even if the solid lubricant is worn and the rotational runout accuracy is not deteriorated. Further, the interference force between the rolling element and the solid lubricant can be suppressed, and excessive wear of the solid lubricant can be suppressed. Further, it is possible to incorporate a solid lubricant having a large volume while suppressing wear of the cage, and it is possible to provide a solid lubricated rolling bearing having smooth rotation and a long life.

It is a developed perspective view which shows the embodiment which applied this invention to a sealed deep groove ball bearing. It is a perspective view of the cage used in the embodiment of FIG. FIG. 3 is a radial cross-sectional view of the bearing in which FIG. 1 is assembled. It is sectional drawing in the axial direction which FIG. 1 was assembled.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a developed perspective view of an embodiment in which the present invention is applied to a sealed deep groove ball bearing.

The bearing 1 has an outer ring 2 having an outer raceway surface 2a on the inner peripheral surface, an inner ring 3 having an inner raceway surface 3a on the outer peripheral surface, a plurality of rolling elements 4, and between adjacent rolling elements 4 and rolling elements 4. A solid lubricant 7 located in the outer ring 2 and a cage 5 for separating the rolling elements 4 in the circumferential direction are provided, and sealing plates 6 are fixed on both sides of the outer ring 2.

As shown in FIG. 2, the cage 5 has a comb shape including an annular portion 5a and six comb tooth portions 5b extending axially from the annular portion 5a and separating the rolling elements 4 in the circumferential direction. be.

The solid lubricant 7 has a comb shape similar to that of the cage 5, and includes an annular portion 7a and six comb tooth portions 7b extending axially from the annular portion 7a and separating the rolling element 4 in the circumferential direction. Consists of.

In the embodiment shown in FIGS. 1 to 4, the cage 5 and the solid lubricant 7 are located on opposite sides in the axial direction so that the annular portions 5a and 7a of the cage 5 and the solid lubricant 7 sandwich the rolling element 4 in the axial direction. , The comb tooth portion 7b of the solid lubricant 7 is inserted inside the comb tooth portion 5b of the cage 5.

In FIGS. 3 and 4, the comb tooth portion 7b of the solid lubricant 7 is shown by cross-hatching.

In the embodiments shown in FIGS. 1 to 4, as described above, the comb tooth portion 7b of the solid lubricant 7 is inserted into the inner diameter side of the comb tooth portion 5b of the cage 5, but the solid lubricant 7 is used. The comb tooth portion 7b may be externally attached to the outer diameter side of the comb tooth portion 5b of the cage 5.

As described above, the cage 5 is composed of a ring portion 5a and a comb tooth portion 5b extending axially from the ring portion 5a and separating the rolling element 4, and the solid lubricant 7 has a comb shape similar to that of the cage 5. By adopting a configuration in which the comb tooth portion 7b of the solid lubricant 7 is located on the inner diameter side or the outer diameter side of the comb tooth portion 5b of the cage 5, the position of the rolling element 4 in the circumferential direction is the position of the cage 5. It is determined by the position of the pocket between the comb teeth 5b. Therefore, even if the solid lubricant 7 is worn, the rolling element 4 is not biased, and the rotational runout accuracy of the bearing 1 is not deteriorated. Further, since the interference force between the rolling element 4 and the solid lubricant 7 is generated not by the rolling element 4 but by the inertial force of the solid lubricant 7 having a small mass, the wear rate of the solid lubricant 7 is alleviated.

The comb tooth portion 5b of the cage 5 is on the opposite side of the solid lubricant 7 on the contact surface with the rolling element 4, that is, as in the embodiment shown in FIGS. 1 to 4, the comb of the solid lubricant 7. When the tooth portion 7b is inserted into the inner diameter side of the comb tooth portion 5b of the cage 5, a protrusion 8 projecting to the outer diameter side of the cage 5 is provided on the comb tooth portion 7b of the solid lubricant 7. When the cage 5 is externally attached to the outer diameter side of the comb tooth portion 5b, the contact surface with the rolling element 4 is enlarged by providing a protrusion 8 protruding on the inner diameter side of the cage 5.

In this way, by providing the protrusion 8 projecting on the opposite side of the solid lubricant 7 on the contact surface between the comb tooth portion 5b of the cage 5 and the rolling element 4, the contact surface is less likely to be worn. .. The life of the solid lubricant rolling bearing can be extended by increasing the volume of the solid lubricant 7, but in order to increase the volume of the solid lubricant 7, it is necessary to reduce the volume of the cage 5. .. In particular, when the solid lubricant 7 is arranged inside or outside the comb tooth portion 5b of the cage 5 as in the present invention, it is necessary to thin the comb tooth portion 5b, but the thinning is a contact. Since it causes premature wear of the surface, in the present invention, by providing the protrusion 8 to expand the contact surface with the rolling element 4, the contact surface pressure between the two is relaxed and the wear of the contact surface is suppressed. is doing.

FIG. 3 is a radial cross-sectional view of the bearing 1 of FIG. 1, and the width dimension W1 of the protrusion 8 is smaller than the width dimension W2 of the outer raceway surface 2a. With such a configuration, it is possible to provide a solid lubricated rolling bearing in which the protrusion 8 does not easily interfere with the raceway ring and the rotation is smooth. That is, by providing the protrusion 8 at a position corresponding to the concave shape of the outer raceway surface 2a, a large clearance between the protrusion 8 and the raceway ring can be obtained.

FIG. 4 is an axial cross-sectional view of the bearing 1 of FIG. 1, and the external dimension D1 formed by connecting the vertices of the protrusions 8 provided on the outer diameter side of the cage 5 is larger than the inner diameter dimension D2 of the outer ring 2. It has a large structure. This makes it possible to increase the volume of the solid lubricant 7. That is, by making the protrusion 8 inside the concave shape of the outer raceway surface 2a, the diameter dimension of the comb tooth portion 5b of the cage 5 can be increased, and the space on the inner diameter side of the comb tooth portion 5b can be increased. can. When the cage 5 is inserted into the outer ring 2, the protrusion 8 is made to be inside the outer raceway surface 2a while the comb tooth portion 5b is elastically deformed toward the inner diameter side.

Further, in the embodiment in which the comb tooth portion 7b of the solid lubricant 7 is externally attached to the outer diameter side of the comb tooth portion 5b of the cage 5, the apex of the protrusion 8 provided on the inner diameter side of the cage 5 is connected. The volume of the solid lubricant 7 can be made larger by making the inner diameter dimension formed by the above 3 smaller than the outer diameter dimension of the inner ring 3. That is, by making the protrusion 8 inside the concave shape of the inner raceway surface 3a, the diameter dimension of the comb tooth portion 5b of the cage 5 can be reduced, and the space on the outer diameter side of the comb tooth portion 5b can be increased. Can be done. When the cage 5 is inserted into the inner ring 3, the protrusion 8 is made to be internal to the raceway surface while the comb tooth portion 5b is elastically deformed to the outer diameter side.

Further, the solid lubricant 7 is formed in the same comb shape as the cage 5, and the comb tooth portion 7b of the solid lubricant 7 is inserted or externally inserted into or externally inserted into the comb tooth portion 5b of the cage 5. It is possible to extend the life of the solid-lubricated rolling bearing, and thus to extend the life of the solid-lubricated rolling bearing. That is, by connecting and integrating the solid lubricant 7 with the annular portion 7a, the behavior of the solid lubricant 7 can be stabilized, and the sticking to the outer ring 2 and the cage 5 due to the centrifugal force can be suppressed. The wear of the solid lubricant 7 can be suppressed.

Further, the configuration of the solid lubricant 7 is further strengthened by configuring the annular portion 5a of the cage 5 and the annular portion 7a of the solid lubricant 7 to be located on opposite sides of the rolling element 4 in the axial direction. can do. That is, the annular portion 7a of the solid lubricant 7 can be configured to be thicker than the configuration in which the annular portions 5a and 7a of the cage 5 and the solid lubricant 7 are arranged on the same side, and the annular portion 7a is broken. The configuration is difficult to do.

The outer diameter end of the sealing plate 6 is press-fitted and fixed to the peripheral groove formed on the inner peripheral surface of the outer ring 2, and the inner diameter end thereof is close to the outer peripheral surface of the inner ring 3 to form a non-contact seal. For bearings and the like that are not used in a high temperature environment, a contact seal type in which the inner diameter end thereof is slidably contacted with the outer peripheral surface of the inner ring 3 can also be used as the sealing plate 6.

The outer ring 2 and the inner ring 3 are made of a steel material, for example, martensitic stainless steel such as SUS440C. The rolling element 4 is made of stainless steel, bearing steel or ceramics, and as the ceramics, for example, silicon nitride can be used.

The cage 5 and the sealing plate 6 are preferably formed of, for example, austenitic stainless steel such as SUS304, which has excellent corrosion resistance.

Further, as the cage 5, a cold-rolled steel plate, a machined cage in which a cylindrical member is turned, and a cage that has been subjected to surface treatment such as salt bath soft nitriding treatment or phosphate coating treatment are also used. Can be adopted.

The solid lubricant 7 is made of a molybdenum disulfide-based, tungsten disulfide-based or graphite-based solid lubricant material.

Note that the present invention is not limited to ball bearings, but can also be applied to roller bearings. Further, the material and shape of the component parts are not limited to the above.

1: Sealed deep groove ball bearing 2: Outer ring 2a: Outer raceway surface 3: Inner ring 3a: Inner raceway surface 4: Rolling element 5: Cage 5a: Ring part 5b: Comb tooth part 6: Sealing plate 7: Solid lubricant 7a: Ring part 7b: Comb tooth part 8: Protrusion

Claims (6)

1. In a solid lubricated rolling bearing in which an inner ring, an outer ring, a plurality of rolling elements, and at least one solid lubricant are arranged between the rolling elements, a cage for separating the rolling elements in the circumferential direction is provided and held. The vessel consists of an annular portion and a comb tooth portion that extends axially from the annular portion and separates the rolling element, and the solid lubricant is located on the inner diameter side or the outer diameter side of the comb tooth portion of the cage. A solid lubricated rolling bearing characterized in that a protrusion protruding on the opposite side of the solid lubricant is provided on the contact surface of the comb tooth portion with the rolling element.
2. The solid lubricated rolling bearing according to claim 1, wherein the axial width dimension W1 of the protrusion is smaller than the axial width dimension W2 of the raceway surface of the outer ring or the inner ring.
3. 2. Solid lubricated rolling bearings as described in.
4. The second aspect of claim 2, wherein the protrusion of the cage is located on the inner diameter side of the cage, and the inner diameter dimension formed by connecting the apex of the protrusion located on the inner diameter side is smaller than the inner ring outer diameter dimension. Solid lubricated rolling bearings.
5. The solid lubricant has a comb shape consisting of an annular portion similar to the cage and a comb tooth portion extending axially from the annular portion, and the comb tooth portion of the solid lubricant is applied to the comb tooth portion of the cage. The solid-lubricated rolling bearing according to any one of claims 1 to 4, wherein the solid-lubricated rolling bearing is internally or externally inserted.
6. The solid lubricated rolling bearing according to claim 5, wherein the annular portion of the cage and the annular portion of the solid lubricant are located on opposite sides of the rolling element in the axial direction.

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