JP2011231863A - Double row bearing cage, and double row roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double row bearing cage consisting of a pair of single row bearing cages each having an annular section and a plurality of pillar sections, the single row bearing cages being arranged such that their back faces abut to each other, wherein the abrasion of the back faces can be reduced, and to provide a roller bearing.SOLUTION: The double row bearing cage consists of the pair of single row bearing cages 1, 1 each having: the annular section 2; and the plurality of pillar sections 3 extending in one of axial directions which are arranged side by side in a circumferential direction on the annular section 2, Here, a pocket 4 is formed among the adjacent pillar sections 3, 3 and the annular section 2 to retain a rolling element 6. An extending direction of the pillars 3 of one of the cages 1, 1 is opposite to an extending direction of the pillars 3 of the another of the cages 1, 1, and both annular sections 2 are arranged such that their back faces abut to each other. A mutually abutted interface between the annular back faces 1a of both cages 1, 1 is formed in intersection with a plane perpendicular to a center axis of the cages.

Description

  The present invention relates to a double row bearing retainer and a rolling bearing used for a cylindrical roller bearing for a machine tool or the like.

  In a spindle device of a machine tool, for example, a double-row cylindrical roller bearing 30 as shown in FIG. 21 is used to rotatably support a spindle driven to rotate at a high speed with respect to a housing. The double-row cylindrical roller bearing 30 holds inner and outer rings 31 and 32, a plurality of cylindrical rollers 26 that are provided between the raceway surface 31 a of the inner ring 31 and the raceway surface 32 a of the outer ring 32, and the cylindrical rollers 26. And a pair of retainers 21 and 21. The retainer 21 in this case includes, as shown in a development view and a side view in FIGS. 22 and 23, an annular portion 22, a plurality of the annular portions 22 that are provided side by side in the circumferential direction and extend in one axial direction. This is a so-called comb-shaped cage in which a pocket 24 for holding the cylindrical roller 26 is formed between the adjacent column portions 23 and 23 and the annular portion 22.

  Conventionally, as a retainer for such a cylindrical roller bearing, one made of a copper alloy has been used in many cases, but in recent years, as a result of efforts for high speed and long life of the bearing, it has been replaced by a resin retainer. (For example, patent document 1).

  If a lightweight and highly rigid resin cage is used as the cage 21 of the double row cylindrical roller bearing 30 in FIG. 22, the influence of the centrifugal force is reduced, so that the interference between the cylindrical roller 26 and the cage 21 is reduced. The temperature rises, and as a result, high speed operation becomes possible.

JP 2005-127493 A JP 2008-008370 A Japanese Patent Laid-Open No. 2005-163997 JP 2006-0777814 A

  However, even when a resin cage is used as the cage 21 in the double-row cylindrical roller bearing 30 in FIG. 21, if the cylindrical roller 26, which is a rolling element, is delayed due to a mounting error of the bearing or the like, as shown in FIG. The pair of cages 21 and 21 that are comb-shaped move toward each other toward the center of the bearing width, and the back surfaces of the two cages 21 are pressed against each other. When vibration due to operation is applied in such a pressed state, wear occurs on the back surface of the cage 21, and the wear powder promotes deterioration of the lubricant and may cause abnormal temperature rise.

  As a countermeasure against such back wear of the cage, there is also a proposal example in which a lubricant holding groove formed on the back of the cage is formed in a region excluding a weld portion that is a merged portion trace of a molten resin at the time of molding (for example, Patent Document 2) is not sufficient as a countermeasure against back wear.

  Further, in the case of such a resin cage, if the above-described cylindrical roller 26 is delayed and a large force is applied to the column portion 23, the annular portion 22 and the column portion are rarely used as shown in FIG. Breakage 40 may occur at 23 connecting portions. Such a break may sometimes occur even in the case of a copper alloy cage. As countermeasures against breakage of such a cage, polyether ether ketone (PEEK) which is strong among resins as a material of the cage is used (for example, Patent Document 1), or the sectional area of the cage is increased (for example, Patent Document 1). There is a proposed example of 3), but it is not sufficient as a countermeasure against breakage.

An object of the present invention is a double-row bearing retainer in which a pair of cages each having an annular portion and a plurality of column portions are arranged so that the back surfaces of the cages are in contact with each other. A cage and double row rolling bearing are provided.
Another object of the present invention is to provide a bearing cage and a double-row rolling bearing capable of preventing breakage at a connecting portion between the annular portion and the column portion in a bearing cage having an annular portion and a plurality of column portions. That is.

  The double row bearing retainer according to the present invention includes an annular portion and a plurality of pillar portions that are arranged in a circumferential direction on the annular portion and extend in one of the axial directions. It consists of a pair of single row cages that form pockets to hold rolling elements between the two parts, and both cages are opposite to each other in the direction in which the pillars extend, and the annular parts are butted against each other on the back In the double-row bearing retainer disposed in a cross-section, the cross-sectional shape of the annular portion back face of each of the retainers is made to intersect with a plane perpendicular to the retainer central axis. . The plane perpendicular to the cage center axis is, for example, a plane at the center position of the bearing width. In this double-row bearing cage, the rolling elements to be held may be cylindrical rollers or balls.

  In a double-row bearing in which a pair of cages are arranged with their annular portions butted against each other on the back, a circumferential force acts on the cage due to the delay of the rolling elements, so that both cages are It is pushed out toward the center, and the back surfaces of the annular portions come into contact with each other and push into each other. In the double row bearing cage of the present invention, the cross-sectional shape of the back surface of the annular part of both cages is a shape that intersects the plane perpendicular to the central axis of the cage. Therefore, the contact area pressure at the time of contact can be reduced. As a result, it is possible to suppress wear generated on the back surfaces of the annular portions of both cages by pressing, reducing the wear powder from promoting deterioration of the lubricant, and avoiding abnormal temperature rise. it can.

  In this invention, the cross-sectional shape of the back surface of the annular portion may be a shape in which the entire back surface is inclined with respect to a plane perpendicular to the cage central axis. Moreover, the cross-sectional shape of the annular part back surface of one cage is a concave V shape, and the cross-sectional shape of the back surface of the annular part of the other cage is the V-shaped back surface of the one cage. It may be a convex V-shape that fits in. Furthermore, the cross-sectional shape of the back surface of the annular portion of one cage is a concave arc shape, and the cross-sectional shape of the back surface of the annular portion of the other cage is the V-shaped back surface of the one cage. A convex arc shape that fits may be used.

In this invention, you may provide the collar part which protrudes to the cyclic | annular part of the other holder | retainer, and covers the outer-diameter surface on the outer diameter surface of the one holder | retainer among both the said holder | retainers.
The cross-sectional shape of the back of the annular part of both cages that intersect each other is made to intersect with the plane perpendicular to the central axis of the cage, thereby reducing wear caused on the back of the annular part of both cages. Although it can be suppressed, the wear cannot be suppressed to zero as long as the back surface is in contact. For this reason, the wear powder is blown to the inner diameter surface of the bearing outer ring by centrifugal force and mixed with the lubricant. Lubricants containing wear powders will deteriorate the lubrication performance, causing damage to the raceway surfaces of the bearing inner and outer rings. If the outer diameter surface of the annular portion of one cage is provided with a collar portion that extends to the annular portion of the other cage and covers the outer diameter surface, this collar portion serves as a pocket for storing wear powder. The wear powder can be prevented from being blown to the inner diameter surface of the bearing outer ring by centrifugal force.

  In this invention, the annular portion and the column portion in each of the cages are separate members, and the annular portion and the column portion are provided on the annular portion and the column portion, respectively. You may make it fit and couple | bond with the to-be-fitted part and fitting part which fit in the direction so that insertion or removal is possible. In the case of this configuration, since the column portion can move in the circumferential direction with respect to the annular portion, when the delayed advancement occurs in the rolling element, the column portion moves in the circumferential direction with respect to the annular portion, The force that pushes both the cages toward the center of the bearing width can be alleviated, so that the wear generated on the back surface of the annular portion can be further reduced.

  In this case, an opening communicating with the fitting portion between the annular portion and the column portion may be provided on the inner diameter surface of the annular portion. When such an opening is provided, the lubricant is introduced from the opening into the contact surface of the fitting portion to contribute to the improvement of the lubricity of the contact surface. Can be easily moved in the circumferential direction.

  Further, when the annular portion and the column portion are separate members as described above, the annular portion and the column are disposed between the fitting portions of the annular portion and the fitted portion and the fitting portion of the column portion. A low friction material having a smaller friction coefficient than the material of the portion may be interposed. When such a low friction material is interposed, the movement of the column portion in the circumferential direction with respect to the annular portion is facilitated when the rolling element is delayed and advanced.

  Further, when the annular portion and the column portion are separate members as described above, a low friction surface treatment is applied to the fitting surface of the fitted portion and the fitting portion of the annular portion and the column portion. May be. Even when the low-friction surface treatment is performed in this manner, the movement of the column portion in the circumferential direction with respect to the annular portion becomes easy when the rolling element is delayed and advanced.

  Further, when the annular part and the pillar part are separate members as described above, the solid lubricant is fired between the fitting parts of the annular part and the fitted part and the fitting part of the pillar part. You may do it. Even when such a solid lubricant is baked, the movement of the column portion in the circumferential direction with respect to the annular portion becomes easy when the rolling element is delayed and advanced.

The double row rolling bearing of the present invention is a double row rolling bearing using the double row bearing retainer of the present invention, and may be a cylindrical roller bearing or a deep groove ball bearing. In the classification according to use, it may be a bearing for a machine tool main shaft.
Since machine tool spindle bearings often operate continuously at high speed, the double row bearing cage of the above configuration, that is, the configuration that can reduce the wear that occurs on the back of the annular portion of the cage when the rolling element is delayed and advanced When this double row bearing cage is used for a machine tool main shaft bearing, it is possible to increase the effect of reducing wear caused on the back surface of the annular portion of the cage.

  The double-row rolling bearing of the present invention may be a bearing having any one of the above-described configurations and may be a grease lubricated bearing. When the cage for double row bearings of any one of the above configurations is used for grease lubrication, when the rolling element is delayed and advanced, it is possible to increase the effect by reducing wear generated on the back surface of the annular portion of the cage. it can.

The cage for double row bearings of the present invention has an annular portion and a plurality of pillar portions that are provided side by side in the circumferential direction on the annular portion and extend in one of the axial directions. It is composed of a pair of single row cages formed with pockets for holding rolling elements between the two cages. In the double-row bearing cage to be arranged, the cross-sectional shape of the back surface of the annular portion of the two cages that face each other is a shape that intersects a plane perpendicular to the cage center axis. Wear can be reduced.
Since the double-row rolling bearing of the present invention uses the double-row bearing cage of the present invention, it is possible to reduce wear on the back surface of the cage, and to prevent deterioration of bearing function and life due to wear powder. .

It is sectional drawing of the double row cylindrical roller bearing using the cage for bearings concerning 1st Embodiment of this invention. It is an expanded view of the holder. It is sectional drawing of the modification of the holder | retainer. (A) is sectional drawing which shows one modification in the fitting part of the annular | circular part and pillar part in the holder | retainer, (B), (C) is the elements on larger scale. It is sectional drawing which shows the other modification in the fitting part of the cyclic | annular part and pillar part in the same holder | retainer. It is sectional drawing which shows the further another modification in the fitting part of the annular part and pillar part in the holder. It is sectional drawing of the other modification of the holder. It is sectional drawing which shows one modification in the fitting part of the annular part and pillar part in the holder | retainer. It is sectional drawing of the double row cylindrical roller bearing using the cage for bearings concerning other embodiment of this invention. It is sectional drawing of the double row cylindrical roller bearing using the cage for bearings concerning further another embodiment of this invention. It is sectional drawing of the double row cylindrical roller bearing using the cage for bearings concerning further another embodiment of this invention. It is sectional drawing of the double row cylindrical roller bearing using the bearing cage concerning a reference proposal example. It is an expanded view of the holder. It is sectional drawing of the modification of the holder | retainer. (A) is sectional drawing which shows one modification in the fitting part of the annular | circular part and pillar part in the holder | retainer, (B), (C) is the elements on larger scale. It is sectional drawing which shows the other modification in the fitting part of the cyclic | annular part and pillar part in the same holder | retainer. It is sectional drawing which shows the further another modification in the fitting part of the annular part and pillar part in the holder. It is sectional drawing of the other modification of the holder. It is sectional drawing which shows one modification in the fitting part of the annular part and pillar part in the holder | retainer. It is an expanded view which shows a part of bearing cage concerning other embodiment of this invention, and shows it in cross section. It is sectional drawing of the double row cylindrical roller bearing using the cage of the prior art example. It is an expanded view of the holder. It is a side view of the holder.

  A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a sectional view of a double row cylindrical roller bearing which is a double row rolling bearing incorporating a double row bearing retainer according to a first embodiment of the present invention. This double-row cylindrical roller bearing 10 is a bearing that rotatably supports a main shaft that is rotationally driven at high speed with respect to a housing in a main shaft device of a machine tool, and includes an inner ring 11 and an outer ring 12, and a plurality of rolling elements. The cylindrical roller 6 and a pair of single-row cages 1 and 1 that hold the cylindrical roller 6. The pair of single row cages 1 and 1 constitute the double row bearing cage W. The inner ring 11 has double-row raceway surfaces 11a and 11a on the outer periphery, and is fitted on the outer periphery of a main shaft (not shown). The outer ring 12 has double-row raceway surfaces 12a and 12a on the inner periphery, and is fitted to the inner periphery of the housing. The cylindrical roller 6 is rotatably interposed between the raceway surface 11 a of the inner ring 11 and the raceway surface 12 a of the outer ring 12. An inner collar 11b is provided at the central portion of the inner ring 11 in the axial direction, and outer collars 11c are provided at both ends. The internal space of the double row cylindrical roller bearing 10 is filled with grease as a lubricant. The material of the cage 1 is a synthetic resin such as polyamide (PA), but may be a metal material.

FIG. 2 is a development view of the pair of cages 1 and 1. These cages 1 are so-called comb cages, each having an annular annular portion 2 and a plurality of column portions 3 provided on the annular portion 2 along the circumferential direction and extending in one of the axial directions. A pocket 4 for slidably holding the cylindrical roller 6 is formed between the adjacent pillar portions 3 and 3 and the annular portion 2. Here, the annular portion 2 and the column portion 3 are integrally formed. The two cages 1 are arranged such that the extending directions of the column portions 3 are opposite to each other, and the respective annular portions 2 are abutted on the back surface.
The cross-sectional shape of the back surface of the annular portion 2 that is abutted with each other of the cages 1 is a shape that intersects a plane O that is perpendicular to the cage center axis, as shown in FIG. The plane O is a plane at the center of the bearing width and is positioned at the center of the bearing width of the double row bearing cage W. In this embodiment, the cross-sectional shape of the back surface 1a of the annular portion 2 is inclined at a predetermined angle with respect to the axis.

  As described above, in the pair of cages 1 and 1 arranged so that the annular portion 2 is abutted with each other on the back surface 1a, a circumferential force as indicated by an arrow in FIG. Thereby, both the cages 1 are pushed toward each other toward the center of the bearing width, and the back surfaces 1a and 1a of the annular portion 2 are brought into contact with each other and pressed. In this embodiment, the cross-sectional shape of the back surface 1a of the annular portion 2 of both cages 1 is a shape that intersects a plane O perpendicular to the cage center axis, and is inclined at a predetermined angle with respect to the cage center axis. Therefore, the area of the back surface 1a of the annular portion 2 of both the cages 1 is increased accordingly, and the contact pressure at the time of contact can be reduced. As a result, wear generated on the back surface 1a of the annular portion 2 of both cages 1 due to the pressing can be suppressed to a small level, and the wear powder can be prevented from accelerating the deterioration of the grease, which is a lubricant. Invitation can be avoided.

  3 to 6 show modifications of the cage 1 in this embodiment. In the configuration example shown in FIGS. 1 and 2, the case where the annular portion 2 and the column portion 3 are integrally formed is shown. However, in the configuration example of FIG. 3, the annular portion 2 and the column portion 3 in each cage 1 Is a separate member, and an example in which the column portion 3 is coupled to the annular portion 2 by fitting. 3 is a cross-sectional view corresponding to the cross-sectional view taken along the line AA in the developed view of FIG. In this modified example, in each cage 1, a fitting portion 3 a having an L-shaped cross section facing the outer diameter side is formed at the proximal end portion of the column portion 3, and the annular portion 2 has a fitting groove facing the inner diameter side. The to-be-fitted part 2a which becomes is formed. These fitting part 3a and to-be-fitted part 2a are shapes which fit in the circumferential direction of the annular part 2 so that insertion or removal is possible. By pushing the column part 3 in the circumferential direction relative to the annular part 2, the fitting part 3 a is fitted into the fitted part 2 a, and the annular part 2 and the pillar part 3 are integrated. The In this case, the material of the members of the annular portion 2 and the column portion 3 may be different materials, for example, the member of the annular portion 2 is polyamide (PA) 66 and the member of the column portion 3 is a copper alloy, The same material may be used. Other configurations are the same as those of the configuration example shown in FIGS.

  In the case of the modification of FIG. 3, since the column portion 3 can move in the circumferential direction with respect to the annular portion 2, the column portion 3 is circular with respect to the annular portion 2 when the cylindrical roller 6 is delayed. By moving in the circumferential direction, it is possible to relieve the force of pushing both the cages 1 toward the center of the bearing width, thereby further reducing wear generated on the back surface of the annular portion 2.

  FIG. 4A shows an example in which the uneven portion 7 is provided on a part of the contact surface of the annular portion 2 and the fitting portion 3a of the column portion 3 that are in contact with each other in the modified example shown in FIG. Indicates. The uneven portion 7 may be provided on the contact surface on the pillar portion 3 side as shown in an enlarged view in FIG. 4B, or the contact surface on the annular portion 2 side as shown in the enlarged view in FIG. May be provided.

  As described above, when the uneven portion 7 is provided on a part of the contact surface in contact with each other in the fitting portion of the annular portion 2 and the column portion 3, the lubricant (here, grease) can be held on the uneven portion 7. The contact area can also be reduced. By improving the lubricity at the contact surface, the movement of the column portion 3 in the circumferential direction with respect to the annular portion 2 becomes easy when the cylindrical roller 6 is delayed and advanced. The improvement of the lubricity on the contact surface in this manner can be more effective in the case of machine tool bearings that are often continuously operated at high speed and grease lubrication. It is desirable that the unevenness of the uneven portion 7 is evenly distributed at three or more locations in consideration of balance.

  FIG. 5 shows an example in which the low friction material 8 is interposed between the contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitting portion of the annular portion 2 and the column portion 3 in the modification shown in FIG. . As the low friction material 8, for example, a resin sheet having excellent sliding characteristics such as Luron sheet (registered trademark) is suitable.

  In this way, even when the low friction material 8 is interposed between contact surfaces of the annular portion 2 and the column portion 3 that are opposite to each other in the fitted portion 2a and the fitting portion 3a of the annular portion 2 and the column portion 3, When the cylindrical roller 6 is delayed, the movement of the column portion 3 in the circumferential direction with respect to the annular portion 2 is facilitated.

  FIG. 6 shows a low friction surface treatment 9 on the contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitted portion 2a and the fitting portion 3a of the annular portion 2 and the column portion 3 in the modification shown in FIG. The example which gave is shown. As the low-friction surface treatment 9, for example, surface treatment such as silver plating, Teflon (registered trademark) processing, or other fluororesin processing is suitable.

  Thus, even when the low friction surface treatment 9 is applied to the contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitting portion of the annular portion 2 and the column portion 3, the cylindrical roller 6 is delayed and advanced. When moving, the movement of the column part 3 in the circumferential direction with respect to the annular part 2 is facilitated.

  In addition, a solid lubricant such as polylube (registered trademark) may be encapsulated and fired in place of the low friction material 8 between the contact surfaces of the annular portion 2 and the column portion 3 in FIG. good. The polylube is made of a resin material containing grease. Also in this case, when the cylindrical roller 6 is delayed and advanced, the movement of the column portion 3 in the circumferential direction with respect to the annular portion 2 is facilitated.

  FIG. 7 shows still another configuration example of the cage 1 in this embodiment. In this configuration example, the annular portion 2 and the column portion 3 are configured as separate members, and in each cage 1, a protrusion having a T-shaped cross section toward the bearing width center is provided on the base end side of the column portion 3. A mating portion 3b is formed, and a fitted portion 2b made of a groove having a T-shaped cross section is formed on a side surface of the annular portion 2 facing the column portion 3 side. Also in this case, by pushing the column portion 3 in the circumferential direction relative to the annular portion 2, the fitting portion 3b is fitted into the fitted portion 2b, and the annular portion 2 and the column portion 3 are thus fitted. Are integrated. Other configurations are the same as those of the configuration example shown in FIGS.

  Also in this configuration example, since the column part 3 can move in the circumferential direction with respect to the annular part 2, when the cylindrical roller 6 is delayed and advanced, the column part 3 is circumferential with respect to the annular part 2. By moving in the direction, it is possible to relieve the force of pushing the two cages 1 toward the center of the bearing width, thereby further reducing the wear generated on the back surface of the annular portion 2.

  FIG. 8 shows an example in which an opening 5 communicating with the fitting portion between the annular portion 2 and the column portion 3 is provided on the inner diameter surface of the annular portion 2 in the configuration example shown in FIG.

  As described above, when the opening 5 communicating with the fitting portion between the annular portion 2 and the column portion 3 is provided on the inner diameter surface of the annular portion 2, the grease is introduced from the opening 5 into the contact surface of the fitting portion and contacts. Since it contributes to improving the lubricity of the surface, the movement of the column part 3 in the circumferential direction with respect to the annular part 2 becomes easy when the cylindrical roller 6 is delayed and advanced.

  In addition, a solid lubricant such as polyrubbe may be encapsulated and fired in the opening 5 in FIG. Also in this case, since the solid lubricant contributes to the improvement of the lubricity of the contact surface in the fitting portion, the movement of the column portion 3 in the circumferential direction relative to the annular portion 2 is caused when the cylindrical roller 6 is delayed and advanced. It becomes easy.

  FIG. 9 shows a cross-sectional view of a double row cylindrical roller bearing incorporating a double row bearing retainer according to another embodiment of the present invention. In this embodiment, in the double-row cylindrical roller bearing 10 shown in FIG. 1, the cross-sectional shape of the annular portion back surface 1 a of one cage 1 is a concave V-shape, and the annular portion back surface 1 a of the other cage 1. Is a convex V-shape that fits with the V-shaped back surface 1 a of the one cage 1. In this embodiment, each modification shown in FIGS. 3 to 8 can be applied.

  Also in this embodiment, since the area of the back surface 1a of the annular portion 2 of both the cages 1 is increased, the contact surface pressure at the time of contact can be reduced. As a result, it is possible to reduce wear caused on the back surfaces of the annular portions 2 of the two cages 1 by pressing.

  FIG. 10 is a cross-sectional view of a double row cylindrical roller bearing incorporating a double row bearing retainer according to still another embodiment of the present invention. In this embodiment, in the double row cylindrical roller bearing 10 shown in FIG. 1, the cross-sectional shape of the annular portion back surface 1 a of one cage 1 is a concave arc shape, and the annular portion back surface 1 a of the other cage 1 is The cross-sectional shape is a convex V-shape that fits into the arcuate back surface 1a of the one cage 1. In this embodiment, each modification shown in FIGS. 3 to 8 can be applied.

  Also in this embodiment, since the area of the back surface 1a of the annular portion 2 of both the cages 1 is increased, the contact surface pressure at the time of contact can be reduced. As a result, it is possible to reduce wear caused on the back surfaces of the annular portions 2 of the two cages 1 by pressing.

  FIG. 11 shows a cross-sectional view of a double row cylindrical roller bearing incorporating a double row bearing retainer of still another embodiment of the present invention. In this embodiment, in the double-row cylindrical roller bearing 10 shown in FIG. 1, of the pair of cages 1, 1, the annular portion of the other cage 1 is arranged on the outer diameter surface of the annular portion 2 of one cage 1. A flange 2c is provided that extends to 2 and covers a part of the outer diameter surface. In the case of the embodiment shown in FIG. 1, the cross-sectional shape of the back surface 1a of the annular portion 2 of the two cages 1 that face each other is an inclined shape that intersects the plane O perpendicular to the cage center axis. It is the same. Also in this embodiment, each modification shown in FIGS. 3 to 8 can be applied.

  By making the cross-sectional shape of the back surface a of the annular portions 2 of the two cages 1 butted against each other with respect to the plane O perpendicular to the central axis of the cage, the annular portions of the two cages 1 are pressed together. Although the wear generated on the back surface of 2 can be suppressed to a low level, the wear cannot be suppressed to zero as long as the back surface 1a is in contact. For this reason, the wear powder is blown to the inner diameter surface of the outer ring 12 by centrifugal force and mixed with grease as a lubricant. Since grease containing wear powder has a poor lubrication performance, the raceway surfaces 11a and 12a of the inner and outer rings 11 and 12 are damaged. In this embodiment, a flange 2c is provided on the outer diameter surface of the annular portion 2 of one retainer 1 so as to project to the annular portion 2 of the other retainer 1 and cover the outer diameter surface. The portion 2c serves as a pocket for storing wear powder, and the wear powder can be prevented from being blown to the inner surface of the outer ring 12 by centrifugal force.

In each of the above embodiments, the ratio W / D × 100% of the circumferential width W of the column part 3 to the diameter D of the cylindrical roller 6 that is a rolling element held in the pocket 4 is 19% or less. Also good.
In the conventional cage, the ratio W / D × 100% of the circumferential width W of the column portion to the radial dimension D of the rolling element held in the pocket was 20 to 33%, but the double row bearing of this embodiment In the cage for use, it can be reduced to about 9 to 19%.
In this case, the ratio W / D × 100% of the circumferential width W of the column part 3 to the diameter D of the rolling element held in the pocket 4 may be 35% or more.

  12 to 19 show reference proposal examples. FIG. 12 shows a cross-sectional view of a double row cylindrical roller bearing incorporating the bearing cage of this proposed example. The retainer 1A is a so-called comb-shaped retainer. As shown in a development view in FIG. 13, the annular portion 2 and the annular portion 2 are provided side by side in the circumferential direction and extend in one axial direction. 1 and 2 that a pocket 4 having a plurality of pillar portions 3 and slidably holding the cylindrical rollers 6 is formed between the adjacent pillar portions 3 and 3 and the annular portion 2. This is the same as the case of the cage 1 of the illustrated embodiment. Further, in the double-row cylindrical roller bearing 10 shown in FIG. 12, the configuration other than the cage 1A is the same as that of the double-row cylindrical roller bearing 10 shown in FIG. In this embodiment, the cross-sectional shape of the back surface of the annular portion 2 of the pair of cages 1A and 1A that face each other is not a shape that intersects the bearing width center as in FIG. Overlapping vertical shape. However, in this case, in the cage 1A, the annular portion 2 and the column portion 3 are separate members, and the column portion 3 is fitted to the annular portion 2 and integrated. In this case, the material of the members of the annular portion 2 and the column portion 3 is, for example, that the member of the annular portion 2 is made of resin such as polyamide (PA) 66, polyphenylene sulfide (PPS), polyether ether ketone (PEEK). The members may be made of different materials such as a copper alloy or the same material. Other configurations are the same as those of the embodiment shown in FIGS.

  FIG. 14 is a cross-sectional view taken along the line BB in the developed view of FIG. In the cage 1A, a fitting portion 3a having an L-shaped cross section facing the outer diameter side is formed on the proximal end side of the column portion 3, and a fitted portion 2a facing the inner diameter side is formed on the annular portion 2. . By pushing the column part 3 in the circumferential direction relative to the annular part 2, the fitting part 3 a is fitted into the fitted part 2 a, and the annular part 2 and the pillar part 3 are integrated. The

  When the cylindrical roller 6 which is a rolling element is delayed and advanced, a force due to the delayed advance of the cylindrical roller 6 acts on the cage 1A in the circumferential direction as shown by an arrow in FIG. However, in the case of the cage 1A of this embodiment, when the cylindrical roller 6 is delayed and advanced, the column portion 3 moves in the circumferential direction with respect to the annular portion 2, so that the moment force is applied to the base end of the column portion 3. In other words, since there is no corner R at the base end of the column part 3, it is possible to prevent breakage at the connecting part between the annular part and the column part as in the conventional example.

Further, it is not necessary to increase the width dimension of the annular portion 2 and the circumferential width of the column portion 3 in order to withstand the moment force applied to the base end of the column portion 3. Therefore, it is possible to increase or decrease the number of pockets 4 by changing the circumferential width of the column part 3. In the conventional comb-shaped cage, the ratio W / D × 100% of the circumferential width W of the column portion to the diameter D of the rolling element held in the pocket is 20 to 33%. It can be reduced to about ˜19%, and the number of cylindrical rollers 6 that are rolling elements can be increased. That is, it is possible to increase the rigidity and load capacity of the cage 1A. Incidentally, when the circumferential width ratio of the column part 3 is 9%, the number of the cylindrical rollers 6 can be increased by 3 per row (6 on both sides of the double row), and increased by about 8% when converted to the basic load rating. Will do. In addition, when the circumferential ratio of the column part 3 is 9%, the circumferential width W of the column part 3 is 2.8 mm to 1.2 mm. In addition, it is good also considering the circumferential direction width ratio of the pillar part 3 as 35% or more.
However,
Circumferential width = {Cage pitch circle diameter− (Rolling body diameter × Rolling body number)} / Rolling body number Circumferential ratio = Circumferential width / Rolling body diameter × 100%
It is.

  In a bearing using a comb-shaped cage, a low heat generation bearing has been proposed in which the number of rolling elements is extracted in one pocket of the cage (for example, Patent Document 4). The one formed integrally can be applied only when the number of rolling elements is an even number. However, in the cage 1A of this embodiment, by changing the circumferential width of the column part 3, the number of cylindrical rollers 6 that are rolling elements can be reduced without being restricted by an odd number or an even number. It can be easily made with low heat generation specifications. If the number of cylindrical rollers 6 that are rolling elements is halved, the circumferential ratio of the column part 3 increases to 140 to 165%. Furthermore, it is also possible to set the circumferential ratio of the column part 3 to 165% or more.

  FIG. 15A shows an example in which the concave and convex portion 7A is provided on a part of the contact surface in contact with each other in the fitting portion of the annular portion 2 and the column portion 3 in the configuration example shown in FIG. The uneven portion 7A may be provided on the contact surface on the pillar portion 3 side as shown in an enlarged view in FIG. 15B, or the contact surface on the annular portion 2 side as shown in the enlarged view in FIG. May be provided.

  As described above, when the uneven portion 7A is provided on a part of the contact surface in contact with each other in the fitting portion of the annular portion 2 and the column portion 3, the lubricant (here, grease) can be held on the uneven portion 7A. The contact area can also be reduced. By improving the lubricity at the contact surface, the movement of the column portion 3 in the circumferential direction with respect to the annular portion 2 becomes easy when the cylindrical roller 6 is delayed and advanced. The improvement of the lubricity on the contact surface in this manner can be more effective in the case of machine tool bearings that are often continuously operated at high speed and grease lubrication. It is desirable that the unevenness of the uneven portion 7A is equally distributed at three or more places in consideration of balance.

  FIG. 16 shows an example in which a low friction material 8A is interposed between contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitting portion of the annular portion 2 and the column portion 3 in the configuration example shown in FIG. . As the low friction material 8A, for example, a resin sheet having excellent sliding characteristics such as Luron sheet (registered trademark) is suitable.

  Thus, even when the low friction material 8A is interposed between the contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitting portion of the annular portion 2 and the column portion 3, the cylindrical roller 6 is delayed and advanced. When it occurs, the movement of the column part 3 in the circumferential direction with respect to the annular part 2 is facilitated.

  FIG. 17 shows an example in which, in the configuration example shown in FIG. 14, the low friction surface treatment 9 </ b> A is applied to the contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitting portion of the annular portion 2 and the column portion 3. As the low friction surface treatment 9A, for example, surface treatment such as silver plating, Teflon (registered trademark) processing, and other fluororesin processing is suitable.

  As described above, even when the low friction surface treatment 9A is applied to the contact surfaces of the annular portion 2 and the column portion 3 facing each other in the fitting portion between the annular portion 2 and the column portion 3, the cylindrical roller 6 is delayed and advanced. When moving, the movement of the column part 3 in the circumferential direction with respect to the annular part 2 is facilitated.

  In addition, instead of the low friction material 8A, a solid lubricant such as polyluve may be encapsulated and fired at the place where the low friction material 8A is interposed between the contact surfaces of the annular portion 2 and the column portion 3 in FIG. Also in this case, when the cylindrical roller 6 is delayed and advanced, the movement of the column portion 3 in the circumferential direction with respect to the annular portion 2 is facilitated.

  FIG. 18 shows still another configuration example of the cage 1A in this embodiment. In this configuration example, the annular portion 2 and the column portion 3 are configured as separate members, and a fitting protrusion 3b having a T-shaped cross section toward the bearing width center is formed on the base end side of the column portion 3 to form an annular shape. A fitting groove 2b having a T-shaped cross section is formed on the side surface of the portion 2 facing the column portion 3 side. Also in this case, by pushing the column portion 3 in the circumferential direction relative to the annular portion 2, the fitting protrusion 3b is fitted into the fitting groove 2b, so that the annular portion 2 and the column portion 3 are fitted. Are integrated. Other configurations are the same as those of the configuration examples shown in FIGS.

  Also in this configuration example, since the column part 3 can move in the circumferential direction with respect to the annular part 2, when the cylindrical roller 6 is delayed and advanced, the column part 3 is circumferential with respect to the annular part 2. By moving in the direction, moment force is not applied to the base end of the column part 3, and it is possible to prevent breakage at the connecting part between the annular part and the column part as in the conventional example.

  FIG. 19 shows an example in which an opening 5 </ b> A communicating with the fitting portion between the annular portion 2 and the column portion 3 is provided on the inner diameter surface of the annular portion 2 in the configuration example shown in FIG. 18.

  As described above, when the opening 5A communicating with the fitting portion of the annular portion 2 and the column portion 3 is provided on the inner diameter surface of the annular portion 2, grease is taken into the contact surface of the fitting portion from this opening 5A and comes into contact. Since it contributes to improving the lubricity of the surface, the movement of the column part 3 in the circumferential direction with respect to the annular part 2 becomes easy when the cylindrical roller 6 is delayed and advanced.

  FIG. 20 shows still another embodiment of the present invention. The bearing cage 1B of this embodiment is obtained by applying the cage structure of the embodiment shown in FIGS. 1 to 11 to a crown type resin cage for a deep groove ball bearing. That is, the cage 1B in this case holds the ball 6A as a rolling element in the pocket 4 as shown in a developed view in FIG. 20, and the annular portion 2 and the annular portion 2 in the circumferential direction. It has a plurality of pillar portions 3 that are provided side by side and extend in one axial direction. The annular portion 2 and the pillar portion 3 are separate members, and the pillar portion 3 is fitted and integrated with the annular portion 2. This is the same as in the case of the cage 1A of the embodiment shown in FIGS. Each pocket 4 holding the ball 6 </ b> A is formed between the adjacent pillar portions 3 and 3 and the annular portion 2. In FIG. 20, only the pillar portions 3 in the cage 1 </ b> B are shown broken away. Although the sectional shape of the fitting portion between the annular portion 2 and the column portion 3 is not shown here, the configuration example shown in FIG. 14 or the configuration example shown in FIG. 18 can be applied. The structural examples shown in FIGS. 15 to 17 and 19 can also be applied to the lubrication structure of the contact surface in the fitting portion.

  In the deep groove ball bearing, the back surfaces of the annular portions of the cage are rarely pressed against each other as in the case of the double row cylindrical roller bearing, but the ball 6A as the rolling element is delayed. If the force due to the delayed advance is large, the ball 6A may abnormally contact the pocket 4 and cause an abnormal temperature rise. In the cage 1B of this embodiment, the annular portion 2 and the column portion 3 are separate members, and the column portion 3 is fitted and integrated with the annular portion 2, and when the ball 6A is delayed and advanced, Since the column part 3 is movable in the circumferential direction with respect to the annular part 2, it is possible to prevent the ball 6 </ b> A from abnormally contacting the pocket 4, and no abnormal temperature rise due to abnormal contact occurs.

DESCRIPTION OF SYMBOLS 1, 1A, 1B ... Cage 1a ... Back surface 2 ... Annular part 2a ... Fitting part 2c ... Collar part 3 ... Column part 3a ... Fitted part 4 ... Pocket 5, 5A ... Opening 6 ... Cylindrical roller (rolling element)
6A ... Ball (rolling element)
7, 7A ... Uneven portion 8, 8A ... Low friction material 9, 9A ... Low friction surface treatment 10 ... Double row cylindrical roller bearing O ... Flat surface

Claims (17)

Each has an annular portion and a plurality of column portions arranged in the circumferential direction in the annular portion and extending in one of the axial directions, and a pocket for holding a rolling element is formed between the adjacent column portion and the annular portion. A pair of single row cages, wherein both cages are opposite to each other in the direction in which the column portions extend, and in the double row bearing cage in which the annular portions are arranged to face each other on the back,
A retainer for double row bearings, characterized in that a cross-sectional shape of the back surfaces of the annular portions of the two retainers that face each other intersects with a plane perpendicular to the center axis of the retainer.   2. The retainer for double row bearing according to claim 1, wherein a cross-sectional shape of the back surface of the annular portion is a shape in which the entire back surface is inclined with respect to a plane perpendicular to the center axis of the cage.   The cross-sectional shape of the back surface of the annular portion of one cage is a V-shaped concave shape, and the cross-sectional shape of the back surface of the annular portion of the other cage is the V-shape of the one cage. A double row bearing retainer having a convex V shape that fits on the back of the shape.   The cross-sectional shape of the back surface of the annular portion of one cage is a concave arc shape, and the cross-sectional shape of the back surface of the annular portion of the other cage is the V-shape of the one cage. A double row bearing retainer having a convex arc shape that fits on the back surface of the bearing.   5. The bag according to claim 1, wherein the outer diameter surface of the two cages projects from the outer diameter surface of the annular portion of one of the cages to the annular portion of the other cage. Cage for double row bearing provided with a section.   In any 1 paragraph of Claims 1 thru / or 5, The above-mentioned annular part and the above-mentioned pillar part in each above-mentioned holder are made into a separate member, and these annular part and a pillar part are made into these annular parts and a pillar part, respectively. A retainer for double-row bearings, which is provided and coupled by a fitted portion and a fitted portion, which are provided and fitted to each other so as to be removably inserted in the circumferential direction of the annular portion.   7. The double row bearing retainer according to claim 6, wherein an opening communicating with the fitting portion between the annular portion and the column portion is provided on the inner diameter surface of the annular portion.   The low friction material having a smaller friction coefficient than the material of the annular portion and the column portion is interposed between the fitting surfaces of the fitted portion and the fitting portion of the annular portion and the column portion according to claim 6. Double row bearing cage.   7. The double row bearing retainer according to claim 6, wherein a low friction surface treatment is applied to a fitting surface of the fitted portion and the fitting portion of the annular portion and the column portion.   7. The double row bearing retainer according to claim 6, wherein a solid lubricant is fired between the fitting surfaces of the fitted portion and the fitting portion of the annular portion and the column portion.   The cage for a double row bearing according to any one of claims 1 to 10, wherein the rolling element is a cylindrical roller and is used for a double row cylindrical roller bearing.   The cage for a double row bearing according to any one of claims 1 to 10, wherein the rolling element is a ball and is used for a double row deep groove ball bearing.   The double row rolling bearing using the cage for double row bearings according to any one of claims 1 to 11.   The double-row rolling bearing according to claim 13, wherein the rolling bearing is a cylindrical roller bearing.   The double-row rolling bearing according to claim 13, wherein the rolling bearing is a deep groove ball bearing.   The double-row rolling bearing according to any one of claims 11 to 15, which is used as a spindle support bearing for a machine tool. The double-row rolling bearing according to any one of claims 11 to 16, wherein the double-row rolling bearing is a grease lubricated bearing.