JP2007298164A - Crown type cage and ball bearing - Google Patents

Abstract

An object of the present invention is to effectively suppress deformation of a cage due to high temperature and high speed, to realize an inexpensive and lightweight cage, and to prevent swinging of the cage during high speed rotation due to light weight.
An annular metal wire 4 having a uniform circular cross section in the circumferential direction is insert-molded in a main portion 1 of a synthetic resin crown-shaped cage. The metal wire 4 is embedded so that one outer peripheral surface of the outer diameter thereof is flush with the end surface of the annular main portion 1 of the synthetic resin crown-shaped cage. Since the metal wire 4 is used, it is cheaper and lighter than the case where the metal plate is insert-molded on the end face of the main part. For example, by reducing the weight of the entire cage, m of the centrifugal force F = mrω ² during rotation can be reduced, so that the swing of the cage during high-speed rotation can be reduced.
[Selection] Figure 1

Description

  The present invention relates to a crown-type cage that holds a plurality of rolling elements in a freely rollable manner, and a ball bearing such as a radial ball bearing that includes the crown-type cage and supports rotating parts of various rotary machine devices.

  For example, a cage shown in FIG. 5 is conventionally known as a cage made of a synthetic resin used for a high-speed rotation bearing. FIG. 5 is a partial perspective view of a synthetic resin crown-shaped cage according to a conventional example (Patent Document 1).

  In the conventional example shown in FIG. 5 (Patent Document 1), a plurality of balls 6 are held by a cage 7 so as to be freely rollable. This cage 7 is called a crown type cage, and is integrally formed by injection molding a synthetic resin. The cage 7 includes an annular main portion 8 made of a synthetic resin and a plurality of sets of pockets 9 and 9 provided on one axial surface (the upper surface in FIG. 5) of the main portion 8. Each of these pockets 9, 9 is composed of a pair of elastic pieces 10, 10 (claw-like portions) that are spaced apart from each other. The mutually opposing surfaces of the pair of elastic pieces 10, 10 constituting each pocket 9, 9 are generally concentric spherical concave surfaces. The balls 6 and 6 are rotatably held in the pockets 9 and 9 by being pushed between the pair of elastic pieces 10 and 10 while elastically expanding the distance between the elastic pieces 10 and 10. Is.

  An annular metal plate 14 is attached to the other axial surface of the main portion 8 (the lower surface in FIG. 5). In this metal plate 14 made of cold rolled carbon steel such as SPCC, circular holes 15 are formed at a plurality of locations in the circumferential direction. Each of these circular holes 15, 15 is a tapered hole whose inner diameter increases with distance from the main portion 8.

  Such a metal plate 14 extends over the entire circumference of the main portion 8 by inserting the metal plate 14 into the mold when the main portion 8 and the elastic pieces 10 and 10 are injection-molded. On the other hand, it is attached non-separated. That is, a part of the synthetic resin constituting the main part 8 and the elastic pieces 10 and 10 is infiltrated into the respective circular holes 15 and 15 to be solidified, thereby firmly connecting the main part 8 and the metal plate 14. Yes.

  As described above, in Patent Document 1, an elastic constant (rigidity) of a metal higher than that of the synthetic resin is used, and the effect thereof is elastic deformation or plastic deformation when the synthetic resin portion is used at high temperature and high speed. It is possible to prevent seizure and damage due to contact with the ring. In addition, an inexpensive and lightweight cage can be realized by using mostly synthetic resin.

  Moreover, in patent document 2, the crown type cage for ball bearings is made by inserting an annular metal element into a synthetic resin. A plurality of recesses are formed on one surface in the axial direction of the annular metal element. A pocket is formed by attaching synthetic resin to the surface of the recess.

Furthermore, in Patent Document 3, a rolling bearing includes a plurality of balls and a metal cage that holds the balls interposed between an inner ring and an outer ring, and at least rolling elements on the surface of the metal cage. A coating resin portion including a polyamide resin is integrally formed on the guide surface.
JP-A-8-145041 Japanese Patent Laid-Open No. 9-79265 JP 2002-323046 A

  However, with further progress in high temperature and high speed, there is a demand for a crown type cage made of a synthetic resin that suppresses deformation of the cage and is inexpensive and lightweight.

  The present invention has been made in view of the circumstances as described above, and can effectively suppress the deformation of the cage due to high temperature and high speed, and can realize an inexpensive and lightweight cage. It is an object of the present invention to provide a crown type cage and a ball bearing that can prevent the cage from swinging during high-speed rotation.

In order to achieve the above object, a crown type retainer according to the present invention includes an annular main portion made of synthetic resin, and a plurality of sets of pockets provided on one axial surface of the main portion,
Each pocket is a crown type cage that is formed integrally with the main part and holds one ball between a pair of elastic pieces that are spaced apart from each other in the circumferential direction. In
An annular member having an elastic constant larger than that of the synthetic resin is insert-molded over the entire circumference of the main portion, and at least a maximum diameter portion of the annular member is embedded in the main portion. .

  Preferably, the annular member having a larger elastic constant than the synthetic resin is corrugated.

  Preferably, the annular member having a larger elastic constant than the synthetic resin is a metal wire.

  Preferably, the cross-section of the annular member having a larger elastic constant than that of the synthetic resin is circular.

  In addition, a ball bearing according to the present invention is characterized in that the crown type cage according to any one of claims 1 to 3 is mounted.

  According to the present invention, by using an annular metal wire, it is possible to minimize the deformation of a pair of elastic pieces (claw-shaped portions) that form a main portion and a pocket of a synthetic resin crown-shaped cage. Since it is made of metal, an inexpensive and lightweight cage can be realized.

  That is, the metal wire of the present invention can be made lighter than the annular metal plate of Patent Document 1, and the effect of preventing the cage swinging during high-speed rotation can be obtained.

  Since the metal wire is fixed inside the resin by insert molding an annular metal wire over the entire circumference of the main part and embedding at least the maximum diameter part of the wire in the main part, the metal It can prevent that the made wire peels from the resin.

  Furthermore, when the cross section of the metal wire is circular, the cross sectional area in the circumferential direction of the metal wire can be manufactured uniformly, and the unbalance due to the centrifugal force accompanying high-speed rotation can be reduced. .

  Hereinafter, a crown type cage and a ball bearing according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a partial perspective view of a synthetic resin crown-shaped cage according to a first embodiment of the present invention.

  The cage according to the present embodiment is called a crown type cage and is integrally formed by injection molding a synthetic resin. The cage includes an annular main portion 1 made of a synthetic resin and a plurality of sets of pockets 2 and 2 provided on one axial surface (the upper surface in FIG. 1) of the main portion 1. Each of these pockets 2 and 2 is made up of a pair of elastic pieces 3 and 3 (claw-like portions) that are spaced apart from each other.

  The mutually opposing surfaces of the pair of elastic pieces 3, 3 constituting each pocket 2, 2 are generally concentric spherical concave surfaces. Each ball (not shown) is rotatably held in each pocket 2 and 2 by pushing between the elastic pieces 3 and 3 while elastically expanding the distance between the elastic pieces 3 and 3. To do.

  In the present embodiment, an annular metal wire 4 having a uniform circular cross section in the circumferential direction is insert-molded in the main portion 1 of the synthetic resin crown-shaped cage.

  The metal wire 4 is embedded so that one outer peripheral surface of the outer diameter thereof is flush with the end surface of the annular main portion 1 of the synthetic resin crown-shaped cage.

  Since the metal wire 4 is used, it is cheaper and lighter than the case where the metal plate is insert-molded on the end face of the main part.

By reducing the weight of the entire cage, m of the centrifugal force F = mrω ² during rotation can be reduced, so that the cage swing during high-speed rotation can be reduced.

Also, since the cross section is an annular metal wire 4 having a uniform circular cross section in the circumferential direction, the r of rotating centrifugal force F = mrω ² is reduced by reducing the unbalance in each phase. As a result, the cage swing during high-speed rotation can be reduced. In this case, r can be reduced by making the rotation center of the main part 1 of the crown-shaped cage made of synthetic resin coincide with the rotation center of the metal wire 4 as much as possible. Centrifugal force r is the difference between the rotational center of the main portion 1 of the synthetic resin crown-shaped cage and the rotational center of the metal wire 4 and the circumferential direction of the synthetic resin crown-shaped cage and the metal wire 4 Since it is influenced by the nonuniformity of the mass in each phase, the shake due to unbalance during rotation can be reduced by making these values as small as possible.

  An annular metal wire 4 is insert-molded over the entire circumference of the main portion 1 of the synthetic resin crown-shaped cage, and the metal wire 4 is inserted into the synthetic resin crown-shaped cage main portion 1. Since the metal wire 4 is fixed inside the resin by embedding the maximum diameter portion of the circular cross section, the metal wire 4 can be prevented from peeling off from the resin.

  The material constituting the pair of elastic pieces 3 and 3 forming the main part 1 and the pockets 2 and 2 of the crown-shaped cage made of synthetic resin is nylon 46, nylon 66, polyphenylene sulfide (PPS), polyether ether ketone. A synthetic resin such as (PEEK) can be used.

  Since these materials have a small coefficient of friction and excellent slidability in contact with metal, the influence of rotation restraint of balls (rolling elements) held in the pockets 2 and 2 can be reduced. Further, by adding about 10 to 40% by weight of a reinforcing material such as glass fiber (GF) or carbon fiber (CF) to these resins, toughness and mechanical strength at high temperature and high speed can be increased.

  As the metal wire 4, carbon steel such as steel for machine structure and piano wire, and metal such as stainless steel, copper alloy, and aluminum alloy are used, and carbon steel and stainless steel having as large an elastic constant as possible are desirable.

  Since the rigidity of the main part 1 is increased by insert-molding the annular metal wire 4 over the entire circumference of the main part 1 of the synthetic resin crown-shaped cage, when the ball bearing is a ball guide, However, even if the elastic piece is deformed by moving in the pockets 2 and 2 of the crown type cage, the deformation at the main portion 1 is suppressed, and the deformation of the elastic pieces 3 and 3 is also suppressed to a small extent. Therefore, the ball bearing using the ball guide cage used at high temperature and high speed is more effective.

(Second Embodiment)
FIG. 2 is a partial perspective view of a synthetic resin crown-shaped cage according to the second embodiment of the present invention.

  In the present embodiment, the number of metal wires 4 is increased to a plurality, and the diameter is changed to large or small. Thereby, deformation can be further suppressed. Other configurations, operations, and effects are the same as those in the first embodiment described above.

  Moreover, it can also be set as the structure (FIG. 1) corresponding to 1st Embodiment by twisting a some thin metal wire so that it may become the one metal wire 4. FIG. In this case, since the rigidity of the annular metal wire 4 can be increased by twisting a plurality of thin wires, the pair of elasticity forming the main portion 1 and the pocket 2 is not limited to the metal wire 4. It is also possible to use a glass fiber or carbon fiber wire having a larger elastic constant than the synthetic resin crown-shaped cage constituting the pieces 3 and 3.

(Third embodiment)
As described above, in the first embodiment, an annular metal wire 4 is insert-molded into a synthetic resin crown-shaped cage, and the metal linear expansion coefficient and Young's modulus are higher than those of the synthetic resin. When used, the effect is to suppress elastic deformation or plastic deformation when the synthetic resin portion is used at high temperature and high speed, and can prevent seizure and breakage due to contact with the ring. In addition, by using synthetic resin for the most part, an inexpensive and lightweight cage can be realized.

  However, in 1st Embodiment mentioned above, when the metal wire 4 is insert-molded in the surface layer of a crown type cage | basket, since the surface of the metal wire 4 is smooth, adhesiveness with a synthetic resin is comparatively comparative. Sometimes it is low.

  FIG. 3 is a partial perspective view of a synthetic resin crown-shaped cage according to a third embodiment of the present invention. The third embodiment is an improvement of the first embodiment.

  In the third embodiment, the metal wire 4 (annular member) is formed in a waveform in advance. Therefore, the adhesion between the metal wire 4 and the synthetic resin can be remarkably improved. Further, as an extremely rare case, even in the case where there is a possibility that the metal wire 4 and the synthetic resin may be peeled in the first embodiment described above, in this embodiment, such peeling is not caused. It can be surely prevented. Other configurations, operations, and effects are the same as those in the first embodiment described above.

(Fourth embodiment)
FIG. 4 is a partial perspective view of a synthetic resin crown-shaped cage according to a fourth embodiment of the present invention. The fourth embodiment is an improvement over the second embodiment.

  Also in the fourth embodiment, the metal wire 4 (annular member) is formed in a waveform in advance. Therefore, the adhesion between the metal wire 4 and the synthetic resin can be remarkably improved. Further, as an extremely rare case, even in the case where there is a possibility that the metal wire 4 and the synthetic resin may be peeled in the second embodiment described above, in this embodiment, such peeling is not caused. It can be surely prevented.

  In addition, by making the number of the metal wires 4 plural, it is possible to secure the necessary and sufficient high rigidity for more severe high speed rotation. Other configurations, operations, and effects are the same as those in the second and third embodiments described above.

  The present invention is not limited to the above-described embodiments and examples, and can be variously modified.

It is a partial perspective view of the crown type cage made of a synthetic resin according to the first embodiment of the present invention. It is a fragmentary perspective view of the synthetic resin crown type cage according to the second embodiment of the present invention. It is a fragmentary perspective view of the synthetic resin crown type cage concerning a 3rd embodiment of the present invention. It is a fragmentary perspective view of the synthetic resin crown type cage concerning a 4th embodiment of the present invention. It is a fragmentary perspective view of the synthetic resin crown type cage concerning a conventional example (patent documents 1).

Explanation of symbols

1 Main part 2 Pocket 3 Elastic piece 4 Metal wire (annular member)
6 ball 7 cage 8 main part 9 pocket 10 elastic piece 14 metal plate 15 circular hole

Claims (5)

An annular main portion made of synthetic resin, and a plurality of sets of pockets provided on one axial surface of the main portion,
Each pocket is a crown type cage that is formed integrally with the main part and holds one ball between a pair of elastic pieces that are spaced apart from each other in the circumferential direction. In
An annular member having an elastic constant larger than that of the synthetic resin is insert-molded over the entire circumference of the main portion, and at least a maximum diameter portion of the annular member is embedded in the main portion. Crown type cage.   The crown-shaped cage according to claim 1, wherein the annular member having a larger elastic constant than the synthetic resin has a corrugated shape.   The crown-shaped cage according to claim 1 or 2, wherein the annular member having a larger elastic constant than the synthetic resin is a metal wire.   The crown-shaped cage according to any one of claims 1 to 3, wherein a cross-section of the annular member having an elastic constant larger than that of the synthetic resin is circular.   A ball bearing comprising the crown-type cage according to any one of claims 1 to 4.

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