Crown-type retainer

Abstract

[Problem] The purpose of the present invention is to provide a crown-type retainer capable of coping with high speed rotation by reducing weight and efficiently supplying lubricating oil between an outer ring and an inner ring. [Solution] A typical configuration of this crown-type retainer according to the present invention is a resin crown-type retainer 100 for retaining rolling elements rolling between inner and outer rings of a bearing 10. The crown-type retainer 100 includes: an annular part 110 centered on the axis of the bearing 10; and a plurality of retaining parts 120 arranged in the circumferential direction of the annular part 110 and having claws for retaining the rolling elements. An axial groove 140 is formed in an outer peripheral surface or an inner peripheral surface between the retaining parts 120.

Description

Crown-shaped cage

[0001] The present invention relates to a crown-shaped cage.

[0002] Generally, bearings use a cage for a shaft (hereinafter referred to as a cage). The cage has a role of maintaining the intervals between rolling elements and preventing the rolling elements from rubbing against each other by holding rolling elements (balls or rollers) in each of a plurality of pockets. There are various shapes of cages used, and one of them is a crown-shaped cage.

[0003] Conventionally, in order to cope with space saving, there has been a case where a press cage formed by punching and molding a metal material is adopted as a bearing for high-speed rotation. However, since the press cage is heavy, the inertia during high-speed rotation becomes high. Therefore, in recent years, a resin cage made of resin may be used instead of the press cage for high-speed rotation.

[0004] For example, Patent Document 1 discloses "a crown-shaped cage including an annular main part made of synthetic resin and a plurality of sets of pockets provided on one axial side of the main part, each pocket integrally formed with the main part and having balls held one by one in a rollable manner between a pair of elastic pieces arranged at intervals in the circumferential direction". The crown-shaped cage of Patent Document 1 is characterized in that "a metal wire, which is an annular member having a higher elastic constant than the synthetic resin, is insert-molded over the entire circumference of the main part, and at least the maximum diameter part of the annular member is embedded in the main part".

[0005] Japanese Patent Application Laid-Open No. 2007-298164

[0006] By adopting the resin cage as described above, the weight of the cage can be reduced and the inertia during high-speed rotation can be lowered. Also, since the back surface of the resin cage is flat, there is an advantage that lubricating oil is less likely to be agitated compared to the press cage. On the other hand, the resin cage tends to block the passage of lubricating oil to the outer ring raceway and the inner ring raceway when assembled to the bearing. Then, the supply of lubricating oil between the outer ring and the inner ring becomes inefficient.

[0007] In view of these problems, the present invention aims to provide a crown-type cage that can handle high-speed rotation by reducing its weight and can efficiently supply lubricating oil between the outer ring and the inner ring.

[0008] To solve the above problems, a typical configuration of the crown-shaped cage according to the present invention is a resin crown-shaped cage that holds rolling elements that roll between the inner and outer rings of a bearing, and includes an annular portion centered on the axis of the bearing, and a plurality of holding portions arranged in the circumferential direction of the annular portion and having claws for holding the rolling elements, with axial grooves formed on the outer or inner circumferential surfaces between the holding portions.

[0009] A metal ring is insert-molded into the annular portion described above. When the claw-side surface of the ring is referred to as the front and the opposite surface as the back, it is preferable that the front surface of the ring is exposed and that the ring is exposed in the groove between the retaining parts.

[0010] The crown-shaped cage described above is a race guide that slides on the outer ring of the bearing, and the cage is preferably a cylindrical pocket.

[0011] According to the present invention, it is possible to provide a crown-shaped retainer that can handle high-speed rotation by reducing its weight and can efficiently supply lubricating oil between the outer ring and the inner ring.

[0012] This is a diagram illustrating a bearing equipped with a crown-type cage according to the first embodiment. This is a diagram illustrating a crown-type cage according to the first embodiment. This is a diagram illustrating a crown-type cage according to the second embodiment, comparing the embodiment with a comparative example. This is a diagram illustrating a crown-type cage according to the third embodiment. This is a diagram illustrating a crown-type cage according to the fourth embodiment.

[0013] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. The dimensions, materials, and other specific numerical values ​​shown in these embodiments are merely examples to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0014] (First Embodiment) Figure 1 is a diagram illustrating a bearing 10 equipped with a crown-shaped cage 100 according to the first embodiment. The bearing 10 comprises an outer ring 12 and an inner ring 14, and rolling elements, which are balls 16, roll between the outer and inner rings. The rolling elements, which are balls 16, are held by the resin crown-shaped cage 100 of the first embodiment.

[0015] In the first embodiment, the crown-shaped retainer 100 is a race guide that slides on the outer ring 12 of the bearing 10. Therefore, the retaining portion 120 that holds the ball 16 in the crown-shaped retainer 100 is cylindrical pocket-shaped.

[0016] Figure 2 illustrates a crown-shaped retainer 100 according to the first embodiment. Figure 2(a) is an overall perspective view of the crown-shaped retainer 100, partially cut out for easier understanding. Figure 2(b) is a partially enlarged view of Figure 2(a).

[0017] As shown in Figure 2(a), the crown-shaped retainer 100 of the first embodiment is composed of an annular portion 110 and a plurality of retaining portions 120. The annular portion 110 is a resin component made of a resin such as nylon (polyamide synthetic resin) or ABS, with the axis of the bearing 10 at its center.

[0018] Multiple retaining parts 120 are molded integrally with the annular part 110 and are arranged in the circumferential direction of the annular part 110. The retaining parts 120 form pockets 124 by a pair of claws 122 that hold the rolling elements.

[0019] Furthermore, in the crown-shaped retainer 100 of the first embodiment, a metal ring 130 is insert-molded into the annular portion 110. The ring 130 is a metal ring-shaped member centered on the axis of the bearing 10. For example, SPCC (cold-rolled steel sheet) can be suitably used as the material for the ring 130, and the ring 130 can be formed by press-working the SPCC.

[0020] In the ring 130, when the side facing the claws 122 is called the front surface 132 and the opposite side is called the back surface 134, as shown in Figure 2(b), the front surface 132 of the ring 130 is exposed between the multiple holding parts 120. As a result, the resin between adjacent claws 122 is eliminated, which makes it possible to lighten the crown-shaped holder 100 and enable it to handle even higher rotational speeds.

[0021] Figure 3 is a diagram comparing an embodiment with a comparative example. The bearing 10A shown in Figure 3(b) is a comparative example. The crown-shaped cage 20 of the bearing 10A is made of resin and does not have a metal ring 130 or groove 140. In this configuration, the width of the annular portion 21 is large in order to maintain the rigidity of the retaining portion 22, and the gap L1 between the outer ring 12 and the inner ring 14 becomes narrow. As a result, the passage L1 for lubricating oil is narrow.

[0022] In contrast, the bearing 10 of the embodiment shown in Figure 3(a) is equipped with the crown-shaped cage 100 described above. As a result, the rigidity of the annular portion 110 is increased by inserting the ring 130, and the width of the annular portion 110 can be narrowed. Furthermore, since a groove 140 is formed in the annular portion 110, the passage L2 for lubricating oil can be widened. As a result, when the bearing 10 rotates, the lubricating oil passes through the groove 140 and flows efficiently into the inside of the bearing 10. Therefore, it becomes possible to efficiently supply lubricating oil between the outer ring 12 and the inner ring 14.

[0023] (Second Embodiment) Figure 4 is a diagram illustrating the crown-shaped holder 200 according to the second embodiment. Figure 4(a) shows a perspective view of the crown-shaped holder 200 of the second embodiment as seen from the front, with a portion cut out for easier understanding. Figure 4(b) shows a perspective view of the crown-shaped holder 200 of the second embodiment as seen from the rear. In the following embodiments, components common to the previously described embodiments are denoted by the same reference numerals, and their description is omitted.

[0024] The crown-shaped retainer 200 of the second embodiment is equipped with a deep annular portion 210 with a groove 240, replacing the annular portion 110 of the crown-shaped retainer 100 of the first embodiment. The groove 240 is formed axially on the inner circumferential surface 212 of the annular portion 210 and between adjacent retaining portions 120.

[0025] Furthermore, a feature of the crown-shaped retainer 200 in the second embodiment is that the front surface 132, back surface 134, and inner circumferential surface 136 of the ring 130 are exposed at the location of the groove 240. With this configuration, the resin portion can be further reduced, thereby making the crown-shaped retainer 200 lighter and enabling it to handle high-speed rotation.

[0026] Furthermore, when insert molding the ring 130 by positioning it within the mold cavity, positioning pins can be applied to the front surface 132, back surface 134, and inner circumferential surface 136 that are expected to be exposed within the groove 240. Therefore, the positional accuracy of the ring 130 inside the crown-shaped retainer 100 can be improved, reducing runout during high-speed rotation and improving NV countermeasures (noise and vibration countermeasures).

[0027] (Third Embodiment) Figure 5 is a diagram illustrating the crown-shaped retainer 300 according to the third embodiment. Figure 5(a) is an overall perspective view of the crown-shaped retainer 300, with a portion cut out for easier understanding. Figure 5(b) is a partially enlarged view of Figure 5(a).

[0028] The crown-shaped holder 300 of the third embodiment includes an annular portion 310 with a groove 340 formed on its outer surface, replacing the annular portion 110 of the crown-shaped holder 100 of the first embodiment. The groove 340 is in communication from the front side to the back side of the crown-shaped holder 300. This configuration also provides the same effects as the crown-shaped holder 100 of the first embodiment.

[0029] (Fourth Embodiment) Figure 6 is a diagram illustrating the crown-shaped retainer 400 according to the fourth embodiment. Figure 6(a) shows the crown-shaped retainer 400 of the fourth embodiment as viewed from the front, with a portion cut out for easier understanding. Figure 6(b) shows the crown-shaped retainer 400 of the fourth embodiment as viewed from the rear.

[0030] The crown-shaped retainer 400 of the fourth embodiment replaces the annular portion 110 of the crown-shaped retainer 100 of the first embodiment with an annular portion 410 having a deep groove 440. The outer circumferential surface 414 of the annular portion 410 has an axial groove 440 formed thereon. A feature of the crown-shaped retainer 400 of the fourth embodiment is that the front surface 132, back surface 134, and outer circumferential surface 138 of the ring 130 are exposed at the location of the groove 440. Therefore, the crown-shaped retainer 400 of the fourth embodiment, like the crown-shaped retainer 200 of the second embodiment, can be improved to accommodate high-speed rotation and reduce noise pollution.

[0031] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to such examples. It will be clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention.

[0032] For example, in each of the embodiments described above, the crown-shaped retainer 100 was described as a race guide that slides on the outer ring. However, the present invention is not limited to this, and can also be applied to a race guide that slides on the inner ring.

[0033] This invention can be used as a crown-shaped retainer.

[0034] 10...Bearing, 12...Outer ring, 14...Inner ring, 16...Ball, 20...Crown-shaped cage, 21...Annular section, 22...Retaining section, 100...Crown-shaped cage, 110...Annular section, 112...Inner circumferential surface, 120...Retaining section, 122...Claw, 124...Pocket, 130...Ring, 132...Front surface, 134...Back surface, 136...Inner circumferential surface, 138...Outer circumferential surface, 140...Groove, 200...Crown-shaped cage, 210...Annular section, 212...Inner circumferential surface, 240...Groove, 300...Crown-shaped cage, 310...Annular section, 314...Outer circumferential surface, 340...Groove, 400...Crown-shaped cage, 410...Annular section, 414...Outer circumferential surface, 440...Groove

Claims

1. A crown-shaped cage made of resin for holding rolling elements that roll between the inner and outer rings of a bearing, comprising: an annular portion centered on the axis of the bearing; and a plurality of holding portions arranged in the circumferential direction of the annular portion and having claws for holding the rolling elements, wherein axial grooves are formed on the outer or inner circumferential surfaces between the holding portions.

2. The crown-shaped retainer according to claim 1, characterized in that a metal ring is insert-molded into the annular portion, and when the claw-side surface of the ring is referred to as the front surface and the opposite surface as the back surface, the front surface of the ring is exposed, and the ring is exposed in the groove between the retaining portions.

3. The crown-shaped retainer according to claim 1, characterized in that the crown-shaped retainer is a race guide that slides on the outer ring of the bearing, and the retainer is a cylindrical pocket.

Images