JP2003214436A - Holder for ball bearing and ball bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent blockage with a ball due to deformation of a retainer caused by fast rotation, and to prevent axial looseness of the ball. <P>SOLUTION: This holder for a ball bearing is provided, in a plurality of circumferential positions of an annular holder body 2, with pockets 8 for rollingly holding the balls 7. Each pocket 8 is provided with a plurality of elastic pieces 9 and 10 projected from one axial end side 5 of the holder body 2, and a pocket body part 12 recessively formed in the holder body 2 between a pair of the elastic pieces 9 and 10. The elastic pieces 9 and 10 are formed by straddling with respect to a pitch circle PC in the radially inner and outer directions R. First regions 14a and 15a on the inside surfaces of the elastic pieces 9 and 10 radially outside the pitch circle PC, and the body part 12 form a spherical recessed surface along the surface shape of the ball 7. Second regions 14b and 15b on the inside surfaces of the elastic pieces 9 and 10 radially inside the pitch circle P are so bent as to approach toward the other elastic piece forming the pair as they are located on the tip side in the projecting direction of the elastic pieces. The radial inside end of the second region is set far from the held ball center C as compared with the spherical recessed surface so as to be positioned separately from the ball 7 held by the pocket 8. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball bearing retainer and a ball bearing.

[0002]

2. Description of the Related Art A cage is for rollingly holding balls between an inner ring and an outer ring in order to keep a plurality of balls rotatably provided between an inner ring and an outer ring at regular intervals. As a conventional cage, there is a so-called crown type cage as shown in FIG. This crown-shaped cage is a pocket 1 for holding balls rotatably at a plurality of positions in the circumferential direction of an annular cage body 101.
01a is provided and configured. Cage pocket 1
01a is formed in a concave shape so as to hold the balls one by one, and has a claw 102 protruding from one end side in the axial direction of the retainer body 101. And as the material of the cage,
It is known that the synthetic resin is superior to the synthetic resin in that the temperature rise during high-speed rotation is small, although it is also made of metal.

[0003]

A crown type cage made of synthetic resin is rotated at a high speed (for example, 15,000 to 18,000 m ^-1).
When used in a degree), the cage is subjected to radial deformation force due to centrifugal force. Even if a centrifugal force is applied, the retainer main body 101 has an annular shape and is hardly deformed even if it is made of synthetic resin. To transform.

Therefore, as shown in FIG. 7, the pocket 1
With respect to the ball 103 held by 01a, the claw 102 is deformed radially outward, the edge 102a at the radially inner end of the claw 102 comes into contact with the ball 103, and the ball is clogged.
There is a problem that the bearing is seized due to the heat generation.

[0005] Here, as taking into consideration the deformation of the cage due to the centrifugal force at a high rotation speed, JP-A-2001-50
There is a cage described in Japanese Patent Publication No. 280 (hereinafter referred to as "prior art document"). However, the cage of the prior art document is
There is a drawback that the balls tend to rattle in the axial direction. That is, in the cage of the prior art document, the claws (referred to as "tabs" in the prior art literature) are not on the radially inner portion of the cage but only on the radially outer portion (see FIG. 7). When the claws (tabs) are deformed radially outward by the centrifugal force, the function of the claws (tabs) to hold the balls in the axial direction becomes small, and the balls are apt to rattle in the axial direction.

The present invention has been made in view of the above problems, and prevents a ball from clogging due to deformation of the cage due to high-speed rotation and also prevents the ball from rattling in the axial direction. An object is to provide a container and a ball bearing.

[0007]

SUMMARY OF THE INVENTION The present invention is a cage for ball bearings, wherein a plurality of pockets for holding balls rollably are provided at a plurality of circumferential positions of a retainer body having an annular shape. Is provided with a plurality of elastic pieces protruding from one end side in the axial direction of the cage main body, and a pocket main body formed in a concave shape in the cage main body between adjacent elastic pieces forming a pair. The piece is formed so as to extend radially inward and outward with respect to the pitch circle formed by connecting the ball centers held in the pockets, and the first range on the inner side surface of the elastic piece that is radially outside the pitch circle, and The pocket body is a spherical concave surface formed so that the distance from the center of the ball is equal so as to follow the surface shape of the ball to be held, and is inside the pitch circle among the inner side surfaces of the elastic piece. The second range is
The distal end side of the elastic piece is curved so as to approach the other elastic piece side of the pair, and the radially inner end of the second range is formed in the spherical concave surface so as to be positioned away from the ball held in the pocket. In comparison, the distance from the center of the held ball is increased.

According to the present invention, since the radially inner end side of the second range, that is, the radially inner end side of the elastic piece is located away from the ball, the elastic piece is deformed radially outward by the centrifugal force. However, it becomes difficult for the radially inner end of the elastic piece to come into contact with the ball, and clogging with the ball is prevented. Moreover, since the elastic piece is formed to extend radially inward and outward with respect to the pitch circle, and the second range on the radially inner side is curved so as to approach the other elastic side of the pair that is closer to the tip end side in the protruding direction, the elastic piece is Even if the ball is deformed in the radial direction, the ball is prevented from rattling in the axial direction.

The second range is a virtual cylinder whose longitudinal direction is oriented in the radial direction of the cage and whose central axis passes through the center of the ball, and the radius of the cross-section circle of the cylinder is the ball's radius. It is preferable that the shape is along the surface of the cylindrical body having substantially the same radius.

Then, in a ball bearing provided with a retainer for rotatably holding a plurality of balls rotatably provided between the inner ring and the outer ring, as the retainer, the above-mentioned retainer is used. By using, the clogging between the cage and the balls can be prevented, and seizure of the ball bearing can be prevented.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show a cage 1 for a ball bearing according to the embodiment. This cage 1 is assembled between an inner ring and an outer ring of a ball bearing, and is rotatably arranged between an inner ring raceway surface formed on the inner ring outer circumferential surface and an outer ring raceway surface formed on the outer ring inner circumferential surface. This is for holding a plurality of balls to be formed at regular intervals. This cage 1 is made of synthetic resin and is configured as a so-called crown type.

The cage 1 is provided with an annular cage main body 2. The cage main body 2 has an outer peripheral surface portion 3 facing the inner peripheral surface of the ball bearing outer ring and an inner peripheral surface facing the outer peripheral surface of the ball bearing inner ring. It has a peripheral surface portion 4, a front surface portion 5 on one end side in the axial direction, and a back surface portion 6 on the other end side in the axial direction. The cage body 2 is provided with pockets 8 for holding the balls 7 at predetermined intervals in the circumferential direction. The pocket 8 is composed of a plurality of claw-shaped elastic pieces 9 and 1 axially protruding from the front portion 5 of the cage body 2.
It has 0. The plurality of elastic pieces 9 and 10 are adjacent to each other.
The two elastic pieces form a pair, and the pair of elastic pieces 9 and 10
However, a plurality of sets are provided in the circumferential direction.

The pocket 8 has a pair of elastic pieces 9 and 10.
The cage body 3 is provided with a recessed pocket body portion 12. The pocket body portion 12 is open on the outer peripheral surface portion 3 side, the inner peripheral surface portion 4 side, and the front surface portion 5 side.
The pocket body portion 12 is formed as a spherical concave surface so as to follow the surface shape of the ball 7. In other words, the concave surface of the pocket body 12 has the same distance from the center C of the ball 7. Further, the distance from the center C of the ball 7 to the spherical concave surface of the pocket body 12 is substantially equal to the radius of the ball 7,
Is slightly larger than the radius of the ball 7 and pocket 8
A slight gap is secured between them, and the balls 7 roll smoothly.

The width of each elastic piece 9 and 10 in the radial direction is the same as the width of the cage main body 2. Therefore, the elastic pieces 9 and 10 have the same width.
The reference numeral 10 exists in the radial direction with respect to the pitch circle PC formed by connecting the centers C of the plurality of balls 7 held by the pockets 8. The pair of elastic pieces 9 and 10 have inner side surfaces 14 and 15 facing each other.
Reference numerals 4 and 15 are regions that are radially outside the pitch circle PC.
The surface shapes are different between the ranges 14a and 15a and the second ranges 14b and 15b (areas shaded in FIG. 2) which are areas radially inside the pitch circle PC. In the present invention, the position of the center C of the ball through which the pitch circle PC passes is not strict, and it is meant to include not only the complete ball center C but also the position in the vicinity thereof.

The first areas 14a and 15a are spherical concave surfaces that follow the surface shape of the ball 7 similarly to the pocket body portion 12, and the spherical concave surface of the pocket body portion 12 and the first area 14 are the same.
The spherical concave surfaces of a and 15a are continuously formed, and have a shape forming a part of a virtual spherical surface having a radius substantially the same as the radius of the ball 7. The cage 1 is mainly rotated by the spherical concave surface of the pocket main body 12 and the spherical concave surfaces of the first ranges 14a and 15a in the same rotation direction (the circumferential direction of the cage) as that of the conventional cage shown in FIGS. With the guide function of, the ball 7 is stably held.

The second ranges 14b and 15b have a shape forming a part of the surface of a virtual cylinder, and the center of the virtual cylinder passes through the center C of the ball 7 and the retainer is arranged in the longitudinal direction. It is directed in the radial direction R. Further, the radius of the cross-section circle of the virtual cylinder is substantially equal to the radius of the ball 7. This second
The ranges 14b and 15b are surfaces continuous with the first ranges 14a and 15a, and the second ranges 14b and 15b of the elastic pieces 9 and 10 that face each other in a pair occupy a part of the virtual cylinder, and thus are retained. Looking in the radial direction (axial direction of the virtual cylinder),
The distance between the two second ranges 14b and 15b is substantially constant. Therefore, the radially inner end 1 of the second range 14b, 15b
7, 18 are distances B from the ball center C compared to the distance A from the ball center C on the spherical concave surfaces of the first ranges 14a and 15a.
Is large, and the inner diameter side of the elastic pieces 9 and 10 is 17, 18 balls 7
It is in a separated position.

In this embodiment, since the elastic pieces 9 and 10 are configured as described above, the ball bearing rotates at a high speed,
Even if the elastic pieces 9, 10 are deformed radially outward, the elastic pieces 9, 1
Since the inner diameter ends 17 and 18 of 0 do not contact the ball 7, the ball 7
No clogging of the bearing occurs and seizure of the bearing does not occur. Moreover, since the second ranges 14b and 15b of the elastic pieces 9 and 10 are formed so as to occupy a part of the circumferential surface of the virtual cylindrical body, when viewed in the elastic piece protruding direction, they approach the other elastic piece. Is curved along the ball 7, and even if the elastic pieces 9 and 10 are deformed radially outward, the second ranges 14b and 15 prevent the ball 7 from moving in the cage axial direction. Is prevented from rattling in the axial direction of the cage.

The present invention is not limited to the above embodiment. For example, the specific shape of the second range can be variously modified within the scope of the claims.

[0019]

According to the present invention, the inner diameter side of the second range,
That is, since the inner diameter end side of the elastic piece is located away from the ball, even if the elastic piece is deformed radially outward by centrifugal force, the inner diameter end of the elastic piece is less likely to contact the ball, Blocking with balls is prevented. Moreover, since the elastic piece is formed to extend radially inward and outward with respect to the pitch circle, and the second range on the radially inner side is curved so as to approach the other elastic side of the pair that is closer to the tip end side in the protruding direction, the elastic piece is Even if the ball is deformed in the radial direction, the ball is prevented from rattling in the axial direction.

[Brief description of drawings]

FIG. 1 is a perspective view of a ball bearing cage.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a plan view of a pocket portion.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a perspective view of a conventional ball bearing cage.

FIG. 6 is a plan view of a pocket portion of a conventional ball bearing cage.

FIG. 7 is a plan view of a pocket portion of the prior art document.

[Explanation of symbols]

1 Ball bearing cage 2 Cage body 8 pockets 7 balls 9 elastic pieces 10 elastic pieces 12 Pocket body 14 Elastic piece inner surface 14a First range 14b Second range 15 Elastic piece inner surface 15a First range 15b Second range 17 Elastic piece inner end (second range inner end) 18 Elastic piece inner end (second range inner end) C ball center PC pitch circle R cage radial direction (virtual cylinder axis direction)

Claims (3)

[Claims] 1. A cage for a ball bearing, wherein a plurality of pockets for rollingly holding balls are provided at a plurality of circumferential positions of an annular cage body, wherein the pockets are shafts of the cage body. A plurality of elastic pieces projecting from one end side in the direction, and a pocket main body formed in a concave shape in the cage main body between adjacent elastic pieces forming a pair, the elastic pieces being held by the pockets. A first range that is formed radially inward and outward with respect to a pitch circle formed by connecting the ball centers, and is on the radially outer side of the pitch circle on the inner side surface of the elastic piece, and the pocket body portion is retained. Is a spherical concave surface formed at equal distances from the center of the ball so as to follow the surface shape of the ball, and the second range on the inner side of the elastic piece that is radially inside the pitch circle is The other bullet that makes a pair toward the tip side in the protruding direction The inner diameter end of the second range is curved so as to approach the sex side, and the distance from the center of the held ball is increased as compared with the spherical concave surface so that the inner diameter end of the second range is located away from the ball held in the pocket. A cage for ball bearings characterized by being characterized by: 2. The second range is an imaginary cylindrical body whose longitudinal direction is oriented in the radial direction of the cage and whose central axis passes through the center of the ball, and the radius of the cross section circle of the cylindrical body is the ball. The cage for ball bearings according to claim 1 or 2, wherein the cage has a shape that is substantially equal to the radius of the surface of the cylindrical body. 3. A ball bearing provided with a cage for rollingly holding a plurality of balls rotatably provided between an inner ring and an outer ring between the inner ring and the outer ring, wherein the cage is the one according to claim 1 or 2. A ball bearing cage according to any one of 2 above.