JP2008261483A - Radial ball bearing cage and radial ball bearing - Google Patents

Abstract

A cage for a radial ball bearing and a radial ball bearing capable of improving lubricity in a pocket are provided.
A radial ball bearing retainer 20 is formed in an annular shape as a whole in order to hold a plurality of balls arranged between raceway surfaces of a radial ball bearing so that the balls can freely roll. Pocket 18 is provided, each pocket has an opening T into which the ball 5 is pushed, and a concave surface portion 29 where the ball is located, and a pair of claw-like portions 16a and 16b are provided near both ends of the opening. The concave surface portion includes a first spherical concave surface portion 21 formed in a spherical shape on the bottom side facing the opening, a second spherical concave surface portion 23 formed in a spherical shape on the claw-shaped portion side, and a first spherical shape. A cylindrical concave surface portion 22 formed in a cylindrical shape around the rolling center axis of the ball between the concave surface portion and the second spherical concave surface portion, and the thickness β of the claw-shaped portion is the entire concave surface portion It is smaller than the wall thickness α of the claw-shaped portion when formed on the spherical concave surface.
[Selection] Figure 2

Description

  The present invention relates to a radial ball bearing retainer and a radial ball bearing that are formed in an annular shape in order to hold a plurality of balls in a freely rolling manner, and pockets are provided at a plurality of locations in the circumferential direction.

  Radial ball bearings are widely used in bearings that support rotating shafts and the like in various rotating machine devices. A schematic configuration of a conventional example of this radial ball bearing is shown in FIG. 3 (Patent Documents 1, 2, and 3 below). reference). A radial ball bearing 10 in FIG. 3 is formed by concentrically arranging an inner ring 2 having an inner ring raceway surface 1 formed on an outer peripheral surface and an outer ring 4 having an outer ring raceway surface 3 formed on an inner peripheral surface. A plurality of balls 5 are provided between the raceway surface 3 so as to be freely rollable. The plurality of balls 5 are held by a cage 6 so as to be freely rollable. FIG. 4 is a perspective view of the cage 6 of FIG.

  As shown in FIG. 4, the cage 6 is formed in an annular crown shape, and is manufactured by injection molding from a resin, and is used in place of a corrugated cage that is manufactured by press molding from a conventional metal. (See Patent Documents 1, 2, and 3 below). 4 includes a pocket 18 provided to hold the balls 5 (FIG. 3) in a plurality of positions in the circumferential direction of an annular main portion 17 so as to be able to roll, and both sides of the pocket 18. A plurality of elastically deformable pairs of elastic pieces 16a and 16b provided on the surface are provided. Each pocket 18 is substantially composed of one side surface of a pair of elastic pieces 16a and 16b arranged at a distance from each other in the main portion 17, and a concave surface portion 19 provided between the pair of elastic pieces 16a and 16b. The whole is formed in a spherical shape. An opening T is formed between the pair of elastic pieces 16a and 16b in the upper portion of each pocket 18 in the figure.

  When the radial ball bearing as shown in FIG. 3 is assembled using the crown type cage 6 shown in FIG. 4, the ball 5 is formed between the tip edges of a pair of claw-like elastic pieces (claw-like portions) 16 a and 16 b of the pocket 18. The gap is elastically expanded and inserted so as to be pushed in from the opening T between the elastic pieces 16a and 16b. Thus, the crown type cage 6 holds the balls 5 in the pockets 18 so that the balls 5 can roll between the inner ring raceway surface 1 and the outer ring raceway surface 3 (FIG. 3). .

As described above, the conventional radial ball bearing retainer is generally a metal corrugated retainer or a resin annular crown retainer with a pocket formed of a single spherical surface. Met.
Japanese Patent No. 3744663 Japanese Patent No. 3035766 JP 2005-133893 A

  FIG. 5 shows a cross-sectional view of the main part of the pocket of the cage 6 cut in the direction of the line VV in FIG. 4. In this cage 6, the concave surface portion 19 of the pocket 18 is a spherical concave surface. Lubricants such as grease filled in the resin are difficult to accumulate, and the lubricity between the concave surface portion 19 and the balls 5 in the pocket 18 may be reduced.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to provide a radial ball bearing retainer and a radial ball bearing that can improve lubricity in a pocket.

  In order to achieve the above object, a radial ball bearing retainer according to the present invention is formed in an annular shape as a whole in order to hold a plurality of balls arranged between raceway surfaces of a radial ball bearing in a freely rolling manner. Pockets are provided at a plurality of locations in the circumferential direction, each pocket has an opening into which the ball is pushed, and a concave surface portion on which the ball is located, and a pair of claw-like portions in the vicinity of both ends of the opening. A radial ball bearing retainer provided, wherein the concave surface portion includes a first spherical concave surface portion formed in a spherical shape on the bottom surface facing the opening portion, and a spherical shape formed on the claw-shaped portion side. Two claw concave surface portions, and a cylindrical concave surface portion formed in a cylindrical shape around the rolling center axis of the ball between the first spherical concave surface portion and the second spherical concave surface portion, and the claw The thickness of the claw-shaped portion is larger than the thickness of the claw-shaped portion when the entire concave surface portion is formed into a spherical concave surface. Characterized in that it is small.

  According to this radial ball bearing retainer, when used in a radial ball bearing, the concave surface portion of the pocket where the ball is located has a first spherical concave surface portion on the bottom surface side and a second spherical concave surface portion on the claw-shaped portion side. Since it is composed of an intermediate cylindrical concave surface portion, a lubricant such as grease filled in the bearing is easily collected between the concave surface portion in the pocket and the ball, and the lubricity in the pocket is improved. In addition, the thickness of the claw-shaped portion is configured to be smaller than the thickness of the claw-shaped portion when the entire concave surface portion is formed into a spherical concave surface, and the claw-shaped portion is thinner than when the entire concave surface portion is a spherical concave surface. Therefore, the mold can be easily released when the cage is molded, and the mold releasability is improved, and the ball is easily pushed from the opening of the cage to the pair of claws when the bearing is assembled. improves.

  In the above radial ball bearing retainer, the first spherical concave surface portion and the second spherical concave surface portion can each be configured to have a radius that is substantially centered on the center of the ball in the pocket.

  In addition, the first spherical concave surface portion and the second spherical concave surface portion may each be configured to have a radius centered at a position shifted from the center of the ball in the pocket.

  Further, by configuring the radial ball bearing retainer from a heat resistant material, the bearing can be used for high temperature applications. Although heat-resistant materials such as PPS materials, PEEK materials, and carbon materials, which are often used as high-temperature cage materials, are fragile materials, even high-temperature cages made of such heat-resistant materials can be used as bearings. Since the ball is easy to push between the pair of claw-shaped portions during the assembly of the ball and the force applied to the claw-shaped portions is small, it is possible to prevent cracks in the claw-shaped portions of the cage during the assembly of the bearing.

  In the radial ball bearing according to the present invention, an inner ring having an inner ring raceway surface on an outer peripheral surface and an outer ring having an outer ring raceway surface on an inner peripheral surface are arranged concentrically with each other, and between the inner ring raceway surface and the outer ring raceway surface, The above-mentioned radial ball bearing retainer is used to hold a plurality of balls, and the bearing is filled with a lubricant.

  According to this radial ball bearing, by using the radial ball bearing retainer, the concave surface portion of the pocket where the ball is located can be divided into a first spherical concave surface portion on the bottom surface side and a second spherical concave surface portion on the claw-shaped portion side. Since it is composed of an intermediate cylindrical concave surface portion, a lubricant such as grease filled in the bearing is easily collected between the concave surface portion in the pocket and the ball, and the lubricity in the pocket is improved. In addition, the thickness of the claw-shaped portion is configured to be smaller than the thickness of the claw-shaped portion when the entire concave surface portion is formed into a spherical concave surface, and the claw-shaped portion is thinner than when the entire concave surface portion is a spherical concave surface. Therefore, the mold can be easily released when the cage is molded, and the mold releasability is improved, and the ball can be easily pushed between the pair of claws from the opening of the cage when the bearing is assembled. .

  In the radial ball bearing, a radius ratio (r ′ / D) between a groove radius (r ′) of at least one of the inner ring raceway surface and the outer ring raceway surface and a diameter (D) of the ball may be 52% or less. preferable. As a result, the area of the inner ring raceway surface and / or outer ring raceway surface that comes into contact with the ball is increased, and the stress on the grooves on the raceway surface is reduced, so that a high load on the bearing can be realized.

  In addition, it is preferable that grease is filled as the lubricant, and the condition of the grease (an index indicating the viscosity of the grease) is in the range of 200 to 280.

  According to the radial ball bearing retainer and the radial ball bearing of the present invention, the lubricity in the pocket can be improved, and the releasability at the time of molding the cage and the assembly of the bearing are improved.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1 is a top view of a main part of a radial ball bearing retainer according to a first embodiment. FIG. 2 is a cross-sectional view of the main part of the radial ball bearing retainer of FIG. 1 cut in the same direction as the VV line direction of FIG.

  The cage 20 according to the present embodiment shown in FIGS. 1 and 2 is a crown-type cage that is formed in an annular shape and is provided with a plurality of pockets 18 in the circumferential direction. 3 and is used for a radial ball bearing as shown in FIG. 3, the parts corresponding to those in FIG.

  As shown in FIGS. 1 and 2, the cage 20 includes a plurality of pockets 18 formed at equal intervals in the circumferential direction of the annular main portion 17 between the outer peripheral portion 27 and the inner peripheral portion 28. Each pocket 18 has an opening T into which the ball 5 is pushed when the bearing is assembled, and a concave surface portion 29 in which the pushed ball 5 is positioned and held.

  As shown in FIGS. 1 and 2, the concave portion 29 of the pocket 18 is provided on the bottom side facing the opening T at the bottom of the figure and has a radius R1 (R1> r (r: A first spherical concave surface portion 21 having a radius of the ball 5)) and a radius R2 (R2) centered on the center O of the ball 5 provided in the vicinity of the claw-like portions 16a and 16b on both sides of the opening T in the upper part of the figure. > R) and provided at each intermediate portion between the first spherical concave surface portion 21 and the second spherical concave surface portion 23, 23, with the rolling center axis v of the ball 5 as the center. And cylindrical concave surface portions 22 and 22 configured in a cylindrical surface shape.

  As shown in FIGS. 2 and 4, the pair of claw-shaped portions 16 a and 16 b are inclined slightly toward the pocket 18 side from the surface 26 of the columnar portion of the annular main portion 17 on both sides of the pocket 18. Configured.

  Each side surface of the claw-like portions 16a and 16b on the pocket 18 side constitutes a part of the concave surface portion 29, and the second spherical concave surface portion 23 and a part of the cylindrical concave surface portion 22 are located. That is, the connection part 25 which the 2nd spherical concave surface part 23 and the cylindrical concave surface part 22 connect is located in each one side by the side of the pocket 18 of nail | claw-shaped part 16a, 16b.

  Compared with the case where the overall shape of the pocket 18 is a spherical concave portion 19 (shown by a broken line in FIG. 2) as shown in FIG. 5, in FIG. 1 and FIG. 2, the concave portion 29 of the pocket 18 is the first spherical concave portion. 21, a cylindrical concave surface portion 22, and a second spherical concave surface portion 23, and the claw-shaped portions 16 a and 16 b are entirely thin. For example, as shown in FIG. 2, the second spherical concave surface portion 23 and a cylindrical shape are formed. 2 is smaller than the horizontal thickness α of the spherical concave surface 19 indicated by the broken line in FIG. 2 (β <α).

  As described above, according to the radial ball bearing retainer 20 of FIGS. 1 and 2, the radial ball bearing similar to that of FIG. 3 is used, and the concave surface portion 29 of the pocket 18 has the first spherical concave surface portion 21 and the cylindrical shape. Since the concave portion 22 and the second spherical concave portion 23 are configured, the lubricant such as grease filled in the bearing is easily collected between the concave portion 19 in the pocket 18 and the ball 5, and the pocket 18. The lubricity inside is improved.

  Furthermore, the claw-like portions 16a and 16b of the retainer 20 are entirely thin, and the claw-like portions 16a and 16b have a thickness smaller than that of the pocket 18 (FIG. 5) made of a standard spherical concave portion 19. Since the thickness is reduced, it becomes easier to release the cage 20 when it is molded from resin by a molding die, the mold release property is improved, and the ball 5 is opened to the opening T of the cage 20 when the bearing is assembled. From the above, it becomes easy to be elastically deformed when being pushed between the pair of claw-like portions 16a and 16b, and the assemblability of the bearing is improved.

  In addition, when the radial ball bearing using the cage 20 is used for high temperature, the cage 20 is also made of a heat-resistant material for high temperature, and is often used for such high temperature, such as PPS material, PEEK material, carbon The heat-resistant material such as a material is a material that can be easily broken, but the configuration as described above requires less force applied to the claw-like portions 16a and 16b when the ball 5 is pushed into the pocket 18 of the cage 20. Therefore, it is effective in preventing cracks in the claw-like portions 16a and 16b of the cage 20 when the bearing is assembled.

<Second Embodiment>
FIG. 7 is a cross-sectional view (a) of a radial ball bearing according to the second embodiment (showing each ring and ball when the radius ratio is 52% or less) and a conventional radial ball bearing (with a radius ratio of 52%). It is sectional drawing (b) of each track ring and ball at the time of exceeding. In FIG. 7, for convenience of explanation, the cage is not shown.

  The cage 20 shown in FIGS. 1 and 2 holds a plurality of balls 5 in each pocket 18 and is incorporated in a radial ball bearing. That is, as shown in FIG. 7A, the radial ball bearing 50 according to the present embodiment includes an outer ring 4 having an outer ring raceway surface 51, an inner ring 2 having an inner ring raceway surface 52, a plurality of balls 5, A cage 20 for holding each ball 5 in each pocket 18 at a uniform position so as to roll freely, and a plurality of balls 5 are arranged between the inner ring raceway surface 52 and the outer ring raceway surface 51 so as to roll freely. It is a thing.

  In the radial ball bearing 50 of FIG. 7A, the inner ring raceway surface 52 of the inner ring 2 has a groove shape having a groove radius r52, and the radius ratio (r52) between the groove radius r52 and the diameter D of the ball 5 (r52). / D) is 52% or less. Similarly, the outer ring raceway surface 51 of the outer ring 4 has a groove shape having a groove radius r51, and the radius ratio (r51 / D) between the groove radius r51 and the diameter D of the ball 5 is 52% or less.

  As described above, in the radial ball bearing 50 according to the present embodiment, each radius ratio between the groove radius r52 of the inner ring raceway surface 52 of the inner ring 2 and the groove radius r51 of the outer ring raceway surface 51 of the outer ring 4 and the diameter of the ball 5 ( r52 / D, r51 / D) is made smaller than 52% applied in the conventional case as shown in FIG. 7B, thereby reducing the stress on the grooves of the raceway surfaces 51, 52 with which the ball 5 contacts. is doing.

  That is, in the case of FIG. 7B, the radius ratio (r11 / D) between the groove radius r11 of the inner ring raceway surface 1 and the diameter D of the ball 5 exceeds 52%. The radius ratio (r13 / D) with the diameter D of the ball 5 exceeds 52%. For this reason, since the area which contacts the ball | bowl 5 in each track surface 1 and 3 becomes small, while the stress on the groove | channel of each track surface 1 and 3 becomes large, FIG. 7 (a) of this Embodiment. ), The respective radius ratios (r52 / D, r51 / D) are 52% or less, and the areas in contact with the balls 5 on the inner ring raceway surface 52 and the outer ring raceway surface 51 are increased. The stress on the groove 52 is reduced. For this reason, the radial ball bearing 50 of this Embodiment can achieve a high load because a high load is possible in the applied bearing device.

  In addition, it is preferable that each above-mentioned radius ratio (r52 / D, r51 / D) is 50% or more.

  The radial ball bearing 50 shown in FIG. 7A is used with a lubricant filled in the bearing. However, it is preferable to use grease as the lubricant. In this case, the grease condition (an index indicating the viscosity of the grease) is used. ) Is preferably in the range of 200 to 280. When using relatively hard grease as a lubricant in this way, if the cage pocket shape is a single spherical shape, it will easily return to the pocket once the grease is pushed out of the pocket while the bearing is in use. Although it is difficult to cause poor lubrication in the cage, according to the radial ball bearing 50 of the present embodiment, a spherical concave surface is formed between the pocket 18 and the ball 5 of the cage 20 as shown in FIG. Grease reservoirs A and B are formed in the vicinity of the boundary between the portion 21 and the cylindrical concave surfaces 22 and 22 and in the vicinity of the boundary between the cylindrical concave surfaces 22 and 22 and the spherical concave surfaces 23 and 23, respectively. B, it is difficult to be pushed out of the pocket 18 and it is easy to return to the pocket 18 even if it is pushed out. Rukoto can. Similarly, in FIG. 6 described later, grease reservoirs A ′ and B ′ are formed in the same manner, and the lubricating performance by the grease can be similarly exhibited and maintained.

  As described above, the best mode for carrying out the present invention has been described. However, the present invention is not limited to these, and various modifications are possible within the scope of the technical idea of the present invention. For example, as shown in FIG. 6, the center of the radius R1 of the first spherical concave surface portion 21 is shifted from the center O of the ball 5 to O1 to make the radius R3 larger than the radius R1, and the second spherical concave surface portions 23, 23 The center of the radius R2 may be shifted from the center O of the ball 5 to O2, so that the radius R4 is larger than the radius R2. Also in the case of FIG. 6, the claw-like portions 16 a and 16 b are configured to be thinner overall than in the case where the overall shape of the pocket 18 is a spherical concave surface portion 19 (shown by a broken line in FIG. 6) as shown in FIG. 5. The horizontal thickness γ of the connecting portion 35 between the second spherical concave surface portion 23 and the cylindrical concave surface portion 22 is smaller than the horizontal thickness α of the spherical concave surface portion 19 shown by a broken line in FIG. γ <α).

It is the figure which looked at the principal part of the radial ball bearing retainer by a 1st embodiment from the upper surface. FIG. 5 is a cross-sectional view of a main part when the radial ball bearing retainer of FIG. 1 is cut in the same direction as the VV line direction of FIG. 4. It is the perspective view which fractured | ruptured partially in order to show the internal structure of the conventional radial ball bearing roughly. It is a perspective view which shows the conventional resin-made crown type holder | retainer which can be arrange | positioned to the radial ball bearing of FIG. It is principal part sectional drawing of the pocket of the holder | retainer cut | disconnected in the VV line direction of FIG. It is a figure which shows the modification of the holder | retainer of FIG. 1, FIG. 2, Comprising: It is a figure similar to FIG. Sectional view (a) of a radial ball bearing according to the second embodiment (showing each ring and ball when the radius ratio is 52% or less) and a conventional radial ball bearing (when the radius ratio exceeds 52%) It is sectional drawing (b) of each bearing ring and ball of (shown).

Explanation of symbols

2 Inner ring 4 Outer ring 5 Ball 50 Radial ball bearing 51 Outer ring raceway surface 52 Inner ring raceway surface 16a, 16a Elastic piece, claw-like part 18 Pocket 19 Concave part 20 Radial ball bearing retainer, Cage 21 First spherical concave part 22 Cylinder Concave surface portion 23 second spherical concave surface portion 25, 35 connecting portion 29 concave surface portion of pocket α thickness of claw-shaped portion when concave surface is spherical surface β thickness of claw-shaped portion in case of FIG. Thickness of claw-shaped portion T Opening portion v Rolling center axis D Diameter of ball 5 r52 Groove radius of inner ring raceway surface r51 Groove radius of outer raceway surface 51 A, B, A ′, B ′ Grease reservoir

Claims (7)

In order to hold a plurality of balls arranged between raceway surfaces of a radial ball bearing in a freely rolling manner, the whole is formed in an annular shape and provided with pockets in a plurality of circumferential directions, and the balls are pushed into each pocket. A radial ball bearing retainer provided with a pair of claw-shaped portions in the vicinity of both ends of the opening,
The concave surface portion includes a first spherical concave surface portion formed in a spherical shape on the bottom surface side facing the opening, a second spherical concave surface portion formed in a spherical shape on the claw-shaped portion side, and the first spherical concave surface portion. And a cylindrical concave surface portion formed in a cylindrical shape centering on the rolling center axis of the ball between the second spherical concave surface portion,
A radial ball bearing retainer characterized in that the thickness of the claw-shaped portion is smaller than the thickness of the claw-shaped portion when the entire concave surface portion is formed into a spherical concave surface.   2. The radial ball bearing retainer according to claim 1, wherein the first spherical concave surface portion and the second spherical concave surface portion each have a radius that is substantially centered on a ball center in the pocket.   2. The radial ball bearing retainer according to claim 1, wherein the first spherical concave surface portion and the second spherical concave surface portion each have a radius centered at a position shifted from the center of the ball in the pocket.   The radial ball bearing retainer according to any one of claims 1 to 3, wherein the retainer is a heat resistant material.   An inner ring having an inner ring raceway surface on an outer peripheral surface and an outer ring having an outer ring raceway surface on an inner peripheral surface are arranged concentrically with each other, and any one of claims 1 to 4 between the inner ring raceway surface and the outer ring raceway surface. A radial ball bearing characterized in that a plurality of balls are held using the radial ball bearing retainer described in item 1 and a lubricant is filled inside the bearing.   The radial according to claim 5, wherein a radius ratio (r '/ D) between a groove radius (r') of at least one of the inner ring raceway surface and the outer ring raceway surface and a diameter (D) of the ball is 52% or less. Ball bearing. Filled with grease as the lubricant,
The radial ball bearing according to claim 5 or 6, wherein the grease has a degree of adjustment in a range of 200 to 280.

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