JP2010091091A - Cage for rolling bearing, and rolling bearing for ct scanner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cage for a rolling bearing and a rolling bearing for a CT scanner, capable of reducing grease leakage, capable of enhancing reliability of the bearing, capable of preventing the CT scanner or a hospital floor from being contaminated, and capable of preventing in advance photographing equipment from being troubled caused by splash of grease. <P>SOLUTION: This crown-shaped cage 6 for the rolling bearing includes pockets 8 having a part opened to one side face of an annular body 7 and for holding a rolling element in its inside, in a plurality of circumferential-directional portions of the annular body 7, and is provided in the rolling bearing equipped with seals in bearing both ends. In the cage 6 for the rolling bearing, the annular body 7 is connected with a plurality of circular-arc-shaped segments 9 having respectively the pockets 8, and a recessed part 17 is provided, on an inner face of each pocket 8, to be extended from a pocket opening edge in a cage inside diameter side to a cage radial direction i.e. a cage outside diameter side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rolling bearing retainer and a CT scanner rolling bearing applied to, for example, a CT scanner as a medical device, a gantry as an inspection unit, and the like.

The medical device field is steadily growing against the background of an aging society, and among them, the CT scanner is particularly attracting attention as an image device that efficiently diagnoses and examines patients.
As shown in FIG. 21, the CT scanner 50 has a gantry as an inspection unit, and an X-ray tube, a detector, and the like for imaging are installed in the rotating portion 51. The CT scanner / gantry bearing 52 has the required functions of speeding up to shorten imaging time, reducing noise to eliminate patient's anxiety, as well as eliminating problems caused by adhesion of oil in imaging equipment and contamination of hospital floors, etc. Prevention of grease leakage is important.

A non-contact seal is applied to the seal attached to the raceway ring in order to suppress the rotating torque cross and heat generation of the gantry. However, since this CT scanner / gantry bearing 52 is a very large bearing, the clearance between the seal and the seal groove is large, and grease easily leaks during the operation of the bearing. Therefore, due to the structure around the bearing seal, grease leakage was reduced by reducing the amount of grease charged and providing a grease reservoir in the cage (Patent Document 1). In addition, if necessary, the grease has been wiped off during the maintenance of the CT scanner after the lubrication and running-in operation.
JP 2004-162879 A

  However, with the demand for high speed and high load bearings for CT scanners and gantry and so-called maintenance-free requirements, it is desirable to add as much grease as possible to improve bearing reliability. However, the higher speed and higher load of the bearing increase the behavior of the cage, and the grease is agitated, making it easier for the grease to leak than before. Moreover, the requirement becomes more severe when it becomes maintenance-free. Grease leakage not only stains the CT scanner device and the hospital floor, but may also cause problems when confirming photographs when it adheres to the imaging equipment.

  An object of the present invention is to reduce grease leakage, improve bearing reliability, and prevent the imaging scanner from malfunctioning due to grease scattering without contaminating the CT scanner device or hospital floor. It is to provide a bearing cage and a rolling bearing for a CT scanner.

  The rolling bearing retainer according to the present invention is a crown-shaped holding for a rolling bearing that has pockets that are partially opened on one side surface of the annular body to hold the rolling elements inside at a plurality of locations in the circumferential direction of the annular body. A rolling bearing retainer provided in a rolling bearing in which a seal is fixed to both ends of either the inner or outer race, and the annular body includes a plurality of arc-shaped segments each having the pocket. A concave portion extending in a radial direction of the cage from a pocket opening edge on the side of the cage that is opposite to the bearing ring to which the seal is fixed is provided on the inner surface of each pocket. And

According to this configuration, when the seal is fixed to the outer ring, the amount of scraping off the grease adhering to the rolling elements by the inner diameter surface of the cage is reduced by the recess. As a result, grease leakage from the rear side of the cage can be suppressed, and adhesion of grease to the outer diameter portion of the inner ring can be prevented. When the seal is fixed to the inner ring, the amount of scraping of the grease adhering to the rolling elements by the outer diameter surface of the cage is reduced by the recess. Thereby, grease leakage from the back side of the cage can be suppressed, and adhesion of grease to the inner diameter portion of the outer ring can be prevented.
Therefore, the grease can be prevented from flowing into the seal groove of the race. Therefore, grease leakage can be suppressed even when a non-contact seal is applied, and the bearing speed can be increased. Due to the effect of preventing the grease from flowing into the seal groove, more grease can be sealed in the bearing. In other words, even if a larger amount of grease is sealed in the bearing, the grease does not flow into the seal groove of the bearing ring, and grease leakage can be reduced. Therefore, it becomes possible to realize maintenance-free. In this manner, grease leakage can be reduced, bearing reliability can be improved, and CT scanner devices and hospital floors can be prevented from becoming dirty, thereby preventing problems in imaging equipment due to grease scattering.

  The dent may be provided at one location so as to spread from the center in the circumferential direction of the cage at the opening edge of the pocket to both sides. When this recess is post-processed with a grindstone or the like, the recess can be quickly processed with one grindstone. In this case, the number of processing steps can be reduced as compared with the case where the recessed portions are provided at a plurality of locations, and thus the manufacturing cost of the cage can be reduced.

  The said recessed part may be provided in multiple places located in the both sides of the center of the holder circumferential direction in the opening edge of the said pocket. In this case, the cage pocket section cross-sectional area can be made larger than that of the cage having the recessed portion provided at one place so as to spread from the center in the circumferential direction of the cage. Therefore, it is possible to increase the strength of the cage as compared with the cage having the recessed portion provided at the one place.

Some of the pockets of the entire circumference have a dent, the other part of the pockets do not have a dent, and each segment has the dent in at least one pocket. Also good. In this case, manufacture of the metal mold | die which shape | molds a holder | retainer becomes easy. This makes it easy to repair and maintain the mold. Therefore, it is possible to reduce the manufacturing cost of the cage.
The rolling bearing cage may be a rolling element guide type.

A side oil sump groove extending in the radial direction of the cage may be provided in a side surface portion facing the cage rotation direction on the inner surface of the pocket. In this case, the grease is held in the side oil sump grooves and contributes to lubrication between the rolling elements and the inner surfaces of the pockets.
When a bottom oil sump groove extending in the axial direction is provided on the bottom surface of the pocket, grease is held in the bottom oil sump groove to contribute to lubrication, and vibration and noise generated by sliding contact between the pocket and the rolling element are reduced. Can be suppressed.

When a slit-like groove extending in the axial direction is provided in the column portion between the pockets, grease accumulates in the groove during operation of the bearing, and the grease leakage preventing effect can be further enhanced.
The cage for a rolling bearing may be a cage used for a double-row angular contact ball bearing.
The cage for rolling bearings may be a cage used for a double-row or single-row four-point contact ball bearing.
The rolling bearing may be a bearing that supports a gantry of a CT scanner, a bearing that rotatably supports an X-ray tube device and an X-ray detector in an X-ray diagnostic apparatus, or a bearing for a turntable.

  A rolling bearing for a CT scanner using the rolling bearing cage according to claim 11 may be used. A CT scanner rolling bearing in which this CT scanner rolling bearing is used for supporting an annular gantry may be used.

  The rolling bearing retainer according to the present invention is a crown-shaped holding for a rolling bearing that has pockets that are partially opened on one side surface of the annular body to hold the rolling elements inside at a plurality of locations in the circumferential direction of the annular body. If the annular body is formed by connecting a plurality of arc segments each having the pocket, and the inner surface of each pocket is fixed to the outer ring with a seal installed on the bearing, the inner diameter side of the cage If the seal is fixed to the inner ring, a recess extending in the radial direction of the cage is provided from the pocket opening edge on the outer diameter side of the cage, so that grease leakage is reduced, bearing reliability is improved, and CT scanner device is provided. In addition, it does not pollute the hospital floor, and it is possible to prevent malfunctions of the photographing apparatus due to grease scattering.

An embodiment of the present invention will be described with reference to FIGS.
The rolling bearing retainer according to this embodiment is applied to, for example, a CT scanner / gantry bearing. As this bearing, the combined double-row angular ball bearing 1 shown in FIG. 1 is employed. This double row angular ball bearing 1 regulates the movement in the axial direction by adjusting the axial internal clearance or applying a preload.
As shown in FIG. 1, the bearing 1 includes inner rings 2 and 2, an outer ring 3 having a double-row raceway surface 3 a, seals 4 and 4, rolling elements 5 and 5, and cages 6 and 6. . Between the raceway surface 3a of the outer ring 3 and the raceway surface 2a of the inner ring 2 in each row, a rolling element 5 made of a ball is movably interposed. The cage 6 holds a plurality of rolling elements 5. In this example, the seal 4 is provided on the outer ring 3 and closes the bearing space between the inner and outer rings 2 and 3. For example, a non-contact seal is applied as the seal 4. Grease is sealed in the bearing space V1.

The cage 6 will be described.
As shown in FIGS. 2 and 3, this rolling bearing cage 6 is a so-called crown-shaped resin cage, and a part of the annular body 7 is opened to hold the rolling element 5 inside. The pocket 8 is provided at a plurality of locations in the circumferential direction of the annular body 7. This cage 6 is a rolling element guide type. The annular body 7 is formed by connecting a plurality of arc-shaped segments 9 each having the pocket 8.
As shown in FIGS. 2 and 4, coupling portions 10 and 11 having shapes that can be fitted to each other are provided at both longitudinal ends of each segment 9. These connecting portions 10 and 11 are segment connecting portions that connect the adjacent segments 9 in the circumferential direction. By combining the corresponding connecting portions 10 and 11 of the adjacent segments 9 and 9, a ring-shaped cage 6 is obtained.

  Of the coupling portions 10 and 11 at both ends, the coupling portion 10 at one end has a fitting projection 10b that projects in the circumferential direction from the coupling body 10a. As for the coupling | bond part 11 of the other end, the fitting recessed part 11b is formed in the end surface of the coupling | bond part main body 11a. The fitting protrusion 10b is formed with a head that is larger than the neck following the neck protruding from the coupling body 10a. The shape of the head is, for example, a circle when viewed in the cage radial direction. It is made into a shape. The fitting recess 11b has a shape in which the entire fitting protrusion 10b is fitted so as to be detachable in the radial direction.

  As shown in FIG. 3, each segment 9 has an arcuate cage body 12 and a convex portion 13. A pair of convex portions 13 and 13 for holding the rolling elements 5 are formed at the locations where the pockets 8 are formed on one surface in the axial direction (B direction) of the cage body 12, and the inner surface of these convex portions 13 is the inner surface of the pocket 8. Part of These convex portions 13 and 13 are claw-shaped along the spherical surface of the ball.

  As shown in a plan view in FIG. 5, the thickness of the cage body 12 is such that the radial direction of the general portion of the cage body 12 with respect to the radial thickness W1 of the peripheral portion of each pocket 8 in the cage body 12. The thickness W2 is reduced. In other words, the peripheral portion of each pocket 8 in the cage main body 12 is formed into a thick portion 12a that is thicker than the radial thickness W2 of the general portion of the cage main body 12, and the cage portion 12a The required radial width of the inner surface is ensured. The general portion of the cage body 12 is a portion excluding the peripheral portion of each pocket 8 in the cage body 12. The general part of the cage body 12 has a uniform thickness over the entire circumference, for example. As shown in FIG. 3, the thick portion 12 a is not provided near the bottom of the pocket 8, and is formed separately at two locations facing in the circumferential direction. The thick portion 12 a extends along the opening edge of the pocket 8 from the tip of the convex portion 13, and continues to the pocket bottom side from the base end of the convex portion 13.

Both side portions in the cage radial direction (A direction) on the inner surface of the pocket 8 are formed as spherical ball holding surfaces 14 and 14 with which the rolling elements 5 are in contact. In FIG. 3, the characters “inner” and “outer” attached to the arrow A indicate the directions of the inner diameter side and the outer diameter side in the cage radial direction A, respectively. The ball holding surface 14 is concentric with the rolling surface of the rolling element 5 and has a slightly larger radius of curvature than the rolling surface.
An intermediate portion in the radial direction of the inner surface of the pocket 8 is a circumferential relief surface 15 where the rolling elements 5 are not in contact with each other. The circumferential relief surface 15 is a bottom surface of a shallow groove extending in the circumferential direction formed with respect to the ball holding surface 14. Specifically, the circumferential relief surface 15 is concentric with the rolling surface of the rolling element 5 and is a spherical concave curved surface having a slightly larger radius of curvature than the rolling surface, or a cylindrical surface. It is a concave curved surface. As shown in FIGS. 6 and 8, chamfered portions 16 are provided on all edge portions of the ball holding surfaces 14 on both sides of the pocket 8 that may contact the rolling elements 5.

As shown in FIG. 9, the inner surface of the pocket 8 is provided with a recess 17 extending from the pocket opening edge on the cage inner diameter side toward the cage radial direction, that is, toward the cage outer diameter side. In this example, as shown in FIG. 1, since the seal 4 installed on the bearing 1 is fixed to the outer ring 3, the recess 17 extends from the pocket opening edge on the cage inner diameter side to the cage outer diameter side. It is provided as follows.
The recess 17 reduces the amount of grease that adheres to the rolling element 5 on the inner diameter surface of the cage 6. Thereby, grease leakage from the back side of the cage can be suppressed, and adhesion of grease to the outer diameter of the inner ring can be prevented.
Further, as shown in FIGS. 10A and 10B, if the wall surface HB between the pockets 8 and 8 (annular portion) is removed, the adhesion of grease to the inner diameter surface of the cage can be further prevented. In FIG. 10B, the removed wall HB is indicated by hatching.

In this example, as shown in FIG. 9, the recessed portion 17 is provided at one position so as to spread from the center OW8 in the cage circumferential direction at the opening edge of the pocket 8 to both sides. The cross-sectional shape of the inner surface of the recessed portion 17 along the circumferential direction of the cage (that is, the cross-sectional shape taken along the plane perpendicular to the central axis of the cage) is smaller than the curvature radius Ra of the concave spherical surface serving as the inner surface of the pocket 8. The arc shape has a radius RCb.
The width W17 of the recessed portion 17 is a width over the entire width W8 of the pocket 8 in the cage circumferential direction. The width W17 of the recess 17 is preferably larger than half of the width W8 of the pocket 8, and more preferably 2/3 or more, or 3/4 or more.

  As shown in FIG. 9B, the inner surface shape of the recessed portion 17 is a cylindrical surface shape that substantially follows the surface of the virtual cylinder VC centered on the radial straight line LC of the cage 6. The virtual cylinder VC may be the surface of a grindstone that processes the recess 17. The concave portion 17 extends from the opening edge on the inner diameter side of the cage to the ball arrangement pitch circle PCD in the radial direction of the cage, and gradually decreases, that is, gradually, from the inner diameter edge of the cage to the ball arrangement pitch circle PCD. The shape is shallow and narrow. In this embodiment, the dent 17 extends just to the ball arrangement pitch circle PCD. However, even if it extends slightly to the outer diameter side of the cage from the ball arrangement pitch circle PCD, the depression 17 slightly extends to the ball arrangement pitch circle PCD. You may not reach it.

  The depth of the concave portion 17 is such that the distance RCc from the center O8 of the concave spherical surface of the pocket inner surface to the deepest position of the concave portion 17 is 1.05 times or more the radius of the rolling element 5 (just 1.05 times). It may be preferable. The radius of curvature Ra of the concave spherical surface serving as the inner surface of the pocket 8 is slightly larger than the radius of the rolling element 5 and is less than 1.05 of the radius of the rolling element 5.

The test results for confirming the grease adhesion will be described.
In this test, a ball bearing incorporating a cage provided with a recess 17 according to the present invention and a ball bearing incorporating a general crown-shaped cage were operated under the same conditions and compared. FIG. 10 shows a grease adhesion state of a ball bearing incorporating a cage provided with a recess 17 according to the embodiment. FIG. 11 shows a grease adhesion state of a ball bearing incorporating a general crown-shaped cage.
From this test result, in the ball bearing (FIG. 12) incorporating a general crown-shaped cage in which the recessed portion 17 is not formed, a large amount of grease exists between the cage inner surface and the outer diameter portion of the inner ring. However, grease is leaking toward the inner ring seal groove on the axially outer side, that is, the front side of the drawing. If a seal member is attached to the outer ring, grease flows between the seal groove and the seal tip, and leaks to the outside of the bearing as the temperature inside the bearing rises.
On the other hand, in the ball bearing (FIG. 11) incorporating the cage 6 provided with the recessed portion 17, a very small amount of grease is recognized on the inner diameter portion of the cage 6, but not on the inner ring outer diameter portion. I understand that there is no.

According to the configuration described above, the amount of scraping off the grease adhering to the rolling element 5 by the inner diameter surface of the cage 6 is reduced by the recess 17. As a result, grease leakage from the rear side of the cage can be suppressed, and adhesion of grease to the outer diameter portion of the inner ring can be prevented. Accordingly, grease flow to the seal groove of the inner ring 2 can be prevented. Therefore, even when a non-contact seal is applied as in this example, grease leakage can be suppressed and the speed of the bearing 1 can be increased. Due to the effect of preventing the grease from flowing into the seal groove, more grease can be sealed in the bearing 1.
In other words, even if a larger amount of grease is sealed in the bearing 1, the grease does not flow into the seal groove of the inner ring 2, and grease leakage can be reduced. Therefore, it becomes possible to realize maintenance-free. In this way, grease leakage can be reduced, bearing reliability can be improved, and CT scanner devices and hospital floors can be prevented from being contaminated, preventing malfunctions and misdiagnosis of imaging equipment due to grease scattering. . The recess 17 in this example is provided at one location so as to spread from the center in the cage circumferential direction at the opening edge of the pocket 8 to both sides. When this recess 17 is post-processed with a grindstone or the like, the recess 17 can be quickly processed with one grindstone. In this case, the number of processing steps can be reduced as compared with the case where the recessed portions 17 are provided at a plurality of locations, and thus the manufacturing cost of the cage 6 can be reduced.

Next, another embodiment of the present invention will be described.
In the following description, the same reference numerals are given to portions corresponding to the matters described in the preceding forms in each embodiment, and overlapping description may be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in the preceding section. Not only the combination of the parts specifically described in each embodiment, but also the embodiments can be partially combined as long as the combination does not hinder.

  The cage in the example of FIG. 13 is a cage according to the embodiment of FIG. 9 in which one recess 17 provided on the inner surface of the pocket 8 is replaced with a plurality (two in this example) of recesses 17. is there. In this example, the recessed portions 17 are two locations located on both sides of the center OW8 in the cage circumferential direction at the opening edge of the pocket 8. The inner surface shape of each recess portion 17 is an arc shape having a radius of curvature Rb smaller than the radius of curvature Ra of the concave spherical surface serving as the inner surface of the pocket 8 in the cross-sectional shape along the circumferential direction of the cage. The said cross-sectional shape is synonymous with the cross-sectional shape which cut the dent part 17 in the plane perpendicular | vertical to a holder | retainer central axis. Specifically, as shown in FIG. 2B, the inner surface shape of each recess portion 17 is a cylindrical surface shape substantially along the surface of each virtual cylinder V centered on the straight line L in the radial direction of the cage 6. . The recessed portion 17 extends from the pocket opening edge on the cage inner diameter side to the vicinity of the ball arrangement pitch circle PCD in the radial direction of the cage, and gradually decreases from the cage inner diameter edge toward the ball arrangement pitch circle PCD. That is, the shape gradually becomes shallower and narrower. The ball arrangement pitch circle PCD is also called a pocket PCD.

The positions of the two recessed portions 17 are, for example, two symmetrical places where the circumferential orientation angle with respect to the center OW8 in the circumferential direction of the cage at the opening edge of the pocket 8 is 40 ° ± 15 °. The depth of the recess 17 is preferably such that the distance Rc from the center O8 of the concave spherical surface of the pocket inner surface to the deepest position of the recess 17 is 1.05 times or more the radius of the rolling element 5 ( It may be just 1.05 times).
When the recesses 17 are provided at a plurality of locations on both sides of the center OW8 in the cage circumferential direction at the opening edge of the pocket 8, the recess 17 spreads from the center OW8 in the cage circumferential direction to one side. The cross-sectional area of the cage pocket portion can be made larger than that of the cage having the recessed portion 17 provided. Therefore, it is possible to increase the strength of the cage as compared with the cage having the recessed portion 17 provided at the one place. In addition, the recess 17 can reduce the amount of grease scraped by the inner diameter surface of the cage 6 → prevent grease adhesion to the inner ring outer diameter part → the effect of preventing grease flow into the inner ring seal groove. Further, as shown in FIGS. 14A and 14B, if the wall surface HB between the pockets 8 and 8 (annular portion) is removed, the adhesion of grease to the inner diameter surface of the cage can be further prevented. In FIG. 14B, the removed wall HB is indicated by hatching.
In this embodiment, the number of the recessed portions 17 is two, but may be three or more.

The retainer in the example of FIG. 15 is provided with a side oil sump groove 18 extending in the radial direction of the retainer on the side surface portion facing the rotational direction of the retainer on the inner surface of the pocket 8. That is, in the inner surface of the pocket 8, a part of the cage rotating direction, that is, a direction intersecting with the circumferential direction of the cage, is a concave oil reservoir that extends in the radial direction (A direction) of the cage body 12. Side oil sump grooves 18 are provided. The side oil reservoir grooves 18 are provided, for example, so as to straddle both axial sides of the cage axial direction position substantially coincident with the pitch circle of the arrangement of the rolling elements 5.
FIG. 16 is a partial cross-sectional view of the cage shown in cross section at the side oil sump groove 18. The side oil sump groove 18 is concentric with the rolling surface of the rolling element 5 that is rotatably held in the pocket 8 and has a curved concave shape having a slightly larger radius of curvature than the curved surface of the ball holding surface 14. It is a curved surface or a concave surface such as a cylindrical surface or a rectangular tube surface. In the illustrated example, the side oil sump groove 18 has a cylindrical shape at the bottom, and has a trapezoidal shape in which the opening side widens and the bottom side narrows as seen in FIG. 17 when the cage is viewed in the radial direction.
15 to 17, the grease is held in the side oil sump grooves 18 and contributes to lubrication between the rolling elements 5 and the inner surfaces of the pockets 8.

15 to 17 is provided with a bottom oil sump groove 19 extending in the axial direction on the bottom surface of the pocket 8. On the inner surface of the pocket 8, a bottom oil sump groove 19 having a concave groove shape is provided at a bottom portion which is a portion opposite to the axial opening 8 a (FIG. 17) sandwiched between the convex portions 13 and 13. The bottom oil reservoir groove 19 has a shape extending in the cage radial direction (A direction). The bottom oil sump groove 19 has a minimum depth to be a surface in contact with the rolling element 5 in a state where the rolling element 5 is at the lowermost part of the pocket 8. You may form deeply in the direction which does not contact.
The bottom oil sump groove 19 satisfies this depth condition, and has a cylindrical surface, a square tube surface, or a concentricity with the rolling surface of the rolling element 5 and a slightly larger curvature than the curved surface of the circumferential relief groove 15. It may be a spherical concave curved surface having a radius.
According to this configuration, the grease is held in the bottom oil sump groove 19 and contributes to lubrication, and vibration and noise generated by sliding contact between the pocket 8 and the rolling element 5 can be suppressed.

The cage in the example of FIG. 18 is provided with a slit-like groove 20a extending in the axial direction (B direction) in the column portion 20 between the pockets 8 and 8. In this case, grease accumulates in the groove 20a during the bearing operation, and the grease leakage preventing effect can be further enhanced.
As shown in FIG. 19, the cage 6 of this embodiment may be provided in a single row four-point contact ball bearing. The cage 6 may be provided in a double row four-point contact ball bearing.
The rolling bearing may be a bearing that rotatably supports the X-ray tube device and the X-ray detector in the X-ray diagnostic apparatus, or a bearing for a turntable.

As shown in FIG. 20, when the seal 4 is fixed to the inner ring, the recessed portion 17 of the cage 6 is provided so as to extend from the pocket opening edge on the cage outer diameter side to the cage inner diameter side. In this case, the amount of grease scraped off the rolling element 5 by the outer diameter surface of the cage 6 is reduced by the recess 17 → preventing the grease from adhering to the inner diameter part of the outer ring → the effect of preventing the grease flow to the outer ring seal groove is obtained. Can do.
Of the all-round pockets 8, some of the pockets 8 have the recessed portions 17, the remaining part of the pockets 8 do not have the recessed portions 17, and each of the segments 9 has at least one pocket 8 with the above-described recessed portions. It may have a portion 17. In this case, manufacture of the metal mold | die which shape | molds the holder | retainer 6 becomes easy. This makes it easy to repair and maintain the mold. Therefore, the manufacturing cost of the cage 6 can be reduced.

It is sectional drawing of the rolling bearing which concerns on one Embodiment of this invention. (A) is the top view of the cage for rolling bearings, (B) is the front view which looked at the cage for rolling bearings from the cage inner diameter side. It is a perspective view which shows a part of retainer for the same rolling bearing. (A) is an enlarged front view of the main part of the cage for the rolling bearing, (B) is a cross-sectional view taken along the line bb in FIG. (A), (C) is a right side view of FIG. (D) is a plan view of FIG. It is the top view which looked at a part of the cage for rolling bearings from the cage axial direction. FIG. 6 is an enlarged plan view of a part of FIG. 5. It is a horizontal sectional view of the important section of the cage for rolling bearings. It is the front view which looked at a part of the cage for rolling bearings from the cage radial direction. (A) is the elements on larger scale of the pocket of the rolling bearing retainer, (B) is the perspective view which shows the state which added the virtual cylinder to the perspective view. (A) is a perspective view showing the form which removed the wall part between the pockets of the cage for rolling bearings, and (B) is a perspective view showing the other form which removed the wall part. (A) is explanatory drawing of the result of the grease leak test of the ball bearing incorporating the holder | retainer provided with the dent part, (B) is the elements on larger scale of (A). (A) is explanatory drawing of the result of the grease leak test of the ball bearing incorporating the general crown-shaped cage, (B) is the elements on larger scale of (A). (A) is a partial enlarged perspective view of another example of the rolling bearing retainer of the present invention, and (B) is a perspective view showing a state in which a virtual cylinder is added to the perspective view. (A) is a perspective view showing the form which removed the wall part between the pockets of the cage for rolling bearings, and (B) is a perspective view showing the other form which removed the wall part. It is a perspective view which shows a part of rolling cage retainer of the further another example of this invention. It is a horizontal sectional view of the important section of the cage for rolling bearings. It is the front view which looked at a part of the cage for rolling bearings from the cage radial direction. It is the front view which looked at the cage for rolling bearings of the further another example of this invention from the cage inner diameter side. It is sectional drawing of the rolling bearing which concerns on other embodiment of this invention. It is sectional drawing of the rolling bearing which concerns on other embodiment of this invention. It is sectional drawing which shows schematic structure of CT scanner.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ball bearing 2 ... Inner ring 3 ... Outer ring 4 ... Seal 5 ... Rolling body 6 ... Cage 7 ... Ring body 8 ... Pocket 9 ... Segment 17 ... Recessed part 18 ... Side oil reservoir groove 19 ... Bottom oil reservoir groove 20a ... Slit-shaped groove

Claims (15)

A crown-shaped rolling bearing retainer having pockets that are partially open on one side surface of the annular body and hold a rolling element inside the annular body at a plurality of locations in the circumferential direction of the annular body, either inside or outside In a rolling bearing retainer provided in a rolling bearing in which seals are fixed to both ends of the bearing ring,
The annular body is formed by connecting a plurality of arc-shaped segments each having the pocket,
Rolling bearing holders characterized in that a concave portion extending in the radial direction of the cage is provided on the inner surface of each pocket from the pocket opening edge on the circumferential surface side of the cage opposite to the bearing ring to which the seal is fixed. vessel.   The rolling bearing cage according to claim 1, wherein the recessed portion is provided at one location so as to spread from the center in the circumferential direction of the cage at the opening edge of the pocket to both sides.   The rolling bearing retainer according to claim 1, wherein the recessed portion is provided at a plurality of locations on both sides of the center in the circumferential direction of the retainer at the opening edge of the pocket.   In any one of Claims 1 thru | or 3, the one part pocket of the perimeter pockets has a dent part, the remaining one part pocket does not have a dent part, and each said segment is A rolling bearing retainer having the recess in at least one pocket.   5. A rolling bearing retainer according to claim 1, wherein the rolling bearing guide type is a rolling element guide type.   The rolling bearing retainer according to any one of claims 1 to 5, wherein side pockets extending in a radial direction of the cage are provided on a side surface portion of the inner surface of the pocket facing the cage rotation direction.   7. A rolling bearing retainer according to claim 1, wherein a bottom oil sump groove extending in the axial direction is provided on the bottom surface of the pocket.   The rolling bearing retainer according to any one of claims 1 to 7, wherein a slit-shaped groove extending in an axial direction is provided in a column portion between pockets.   9. A rolling bearing cage according to claim 1, wherein the rolling bearing cage is a cage used for a double-row angular ball bearing.   9. The rolling bearing retainer according to claim 1, wherein the retainer is a retainer used for a double-row or single-row four-point contact ball bearing.   The rolling bearing retainer according to any one of claims 1 to 10, wherein the rolling bearing is a bearing that supports a gantry of a CT scanner.   The rolling bearing retainer according to any one of claims 1 to 10, wherein the rolling bearing is a bearing that rotatably supports an X-ray tube device and an X-ray detector in an X-ray diagnostic apparatus.   The rolling bearing cage according to any one of claims 1 to 10, wherein the rolling bearing is a bearing for a turntable.   A rolling bearing for a CT scanner using the rolling bearing cage according to claim 11.   A rolling bearing for a CT scanner using the rolling bearing for a CT scanner according to claim 14 for supporting an annular gantry.

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