JP4192515B2 - Resin cage for angular contact ball bearings - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a machined resin retainer used for an angular ball bearing.
[0002]
[Prior art]
Conventional examples of this type of resin cage are shown in FIGS. In the figure, 81 is an angular ball bearing, 82 is an inner ring, 83 is an outer ring, 84 is a ball, and 85 is a resin cage.
[0003]
The resin retainer 85 has a shape in which a ball retaining pocket 86 made of a hole penetrating in a direction along the load action line X of the angular ball bearing 81 is provided at several circumferential positions of the annular body, and the virtual cylindrical surface Y A plurality of bridges connecting a plurality of circumferential positions of the large ring portion 87 and the small ring portion 88, the large ring portion 87 disposed on the outer diameter, the small ring portion 88 disposed on the inner diameter than the virtual cylindrical surface Y, and the large ring portion 87. Divided into part 89. The virtual cylindrical surface Y is obtained by extending the pitch circle diameter of each pocket 86 (the diameter of a circle connecting the centers of all pockets 86) in the axial direction, and is indicated by a two-dot chain line in the figure. ing.
[0004]
The pocket 86 includes a through hole surrounded by the large ring portion 87 and the small ring portion 88 and two bridging portions 89 adjacent in the circumferential direction. The pocket 86 includes a substantially semicircular first recess 90 formed by two large bridging portions 89 adjacent to the large ring portion 87 in the circumferential direction, and two bridging portions 89 adjacent to the small ring portion 88 in the circumferential direction. Are combined with a substantially semicircular second recess 91 made of
[0005]
In each of the two bridging portions 89 and 89 adjacent in the circumferential direction, a spherical concave surface in which the inner surface of the first recess 90 and the inner surface of the second recess 91 are set to the same curvature as the curvature of the ball 84. I have to.
[0006]
Further, with respect to the outer diameter surface of the bridging portion 89, the plane 89a along the axial direction and the inclined surface 89b are joined at the center in the axial direction, and the joined portion 89c is a virtual cone connecting the large ring portion 87 and the small ring portion 88 with a straight line. While the inner surface of the bridging portion 89 has a shape arranged on the outer diameter side of the surface Z1, the plane 89d and the inclined surface 89e along the axial direction are joined at the center in the axial direction, and the joined portion 89f is a large ring portion. 87 and the small ring portion 88 are arranged on the inner diameter side with respect to the virtual conical surface Z2 connecting the straight line.
[0007]
Further, the interval W3 between the opening edges C1 and C2 on the outer diameter side of the first recess 90 is set smaller than the diameter of the ball 84 and larger than the interval W4 between the opening edges D1 and D2 on the inner diameter side of the second recess 91. Has been.
[0008]
With the above-described configuration, the conventional resin retainer 85 prevents the ball 84 from coming out from the inside of the pocket 86 to the inner diameter side and the outer diameter side. This is done by forcibly fitting from the outer diameter side.
[0009]
As the angular ball bearing 81 incorporating the resin retainer 85 is rotated, the resin retainer 85 is rotated and guided by the ball 84 that revolves while rotating. In the process, the bridge portion 89 has an outer diameter side. The ball 84 comes into contact with the end edge (C1, C2 in FIG. 17) of the joint portion 89c.
[0010]
In the state where the center of the pocket 86 and the center of the ball 84 are aligned, the radial gap Δ3 between the outer diameter edge of the first recess 90 and the ball 84 is equal to the inner diameter edge of the second recess 91 and the ball 84. Is almost the same as the radial gap Δ4.
[0011]
[Problems to be solved by the invention]
The conventional resin retainer 85 is rotated and guided by the balls 84 so that the balls 84 come into contact with the end edges (C1 and C2 in FIG. 17) of the outer diameter side joint portion 89c in the bridging portion 89. Since the contact position is close to the position where the peripheral speed is maximum in the ball 84, the torque is likely to increase and the heat is easily generated.
[0012]
In addition, in the conventional resin retainer 85, the radial expansion Δ3 on the outer diameter side and the radial clearance Δ4 on the inner diameter side are substantially the same. For example, as shown by a two-dot chain line in FIG. When the diameter is increased, the edges (D1 and D2 in FIG. 18) of the joint portion 89f on the inner diameter side come into contact with the ball 84 in the bridging portion 89 of the pocket 86. Since it is close to the position where the peripheral speed is maximum at 84, the torque is likely to increase and heat is likely to be generated.
[0016]
[Means for Solving the Problems]
Tree fat retainer of the present invention is to spaced a plurality of balls provided in angular contact ball bearings at predetermined intervals, and the large-flowered portion on a circle diameter or the inner diameter connecting the centers of each of the balls, the outer diameter of the ball A small ring portion having a diameter equal to or smaller than the diameter connecting the respective centers, and a bridging portion connecting the large ring portion and several circumferential points of the small ring portion, and in the circumferential direction between the large ring portion and the small ring portion. A ball holding pocket comprising a hole penetrating in a direction along the load acting line of the angular ball bearing is formed by two adjacent bridging portions. The pocket includes a first concave portion having a substantially semicircular radial cross section formed by the two large bridging portions and the two bridging portions adjacent in the circumferential direction, and two bridging portions adjacent to the small ring portion in the circumferential direction. The radial cross-section made by is configured by combining a substantially semicircular second recess. The inner surface of the first recess and the inner surface of the second recess are spherical concave surfaces set to have the same curvature as the curvature of the ball, and the center of the cage in the outer diameter side opening of the first recess The distance from the deepest portion viewed from the axial center to the deepest portion viewed from the central axial direction center of the cage in the outer diameter side opening of the second recess is smaller than the diameter of the ball, and the first recess Is set smaller than the distance from the deepest portion of the inner diameter side opening of the cage viewed from the center in the central axis direction to the deepest portion of the inner diameter side opening of the second recess viewed from the center of the cage in the central axis direction. The deepest portion of the outer diameter surface of the bridging portion viewed from the center in the central axial direction of the cage at the outer diameter side opening of the first recess is the junction between the slope near the large ring and the slope near the small ring. And the central axis of the cage in the outer diameter side opening of the second recess It is disposed on the inner diameter side than the virtual conical surface connecting the deepest portion when viewed from the direction the center in a straight line.
[0017]
In this case, in the process in which the resin cage is rotated and guided by the ball, the ball is located at the deepest portion viewed from the center axis direction center of the cage at the outer diameter side opening of the first recess and the outer diameter side opening of the second recess . The cage comes into contact with the deepest portion viewed from the center in the central axis direction . Since this contact position is close to a position where the peripheral speed of the ball is small, torque increase and heat generation can be reduced as compared with the conventional example.
[0018]
By the way, in a state where the center of the pocket and the center of the ball are aligned, a radial gap between the inner diameter edge of the second recess and the ball is expanded when the large ring portion and the small ring portion are thermally expanded. It can be set larger than the diameter dimension. In this case, even if the crown type cage is thermally expanded, it is possible to prevent interference with the ball.
[0019]
In addition, with respect to the inner surface of the second recess, a spherical concave surface having the same radius of curvature as the inner surface of the first recess is provided in the outer diameter side region, and a semi-cylinder along the radial direction in the radial intermediate region. In addition, a spherical concave surface having a radius of curvature larger than the radius of curvature of the concave surface of the outer diameter side region can be provided in the inner diameter side region. If the second concave portion of the bridging portion is stepped in this way, even when the concave surface on the inner diameter side of the second concave portion comes into contact with the ball when the resin cage swings in the radial direction, the contact is between the spherical surfaces. Because it becomes the contact of the ball, it is not necessary to obstruct the movement of the ball.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
1 to 11 show an embodiment of the present invention. In the figure, 1 indicates the entire angular ball bearing. The angular ball bearing 1 includes an inner ring 2, an outer ring 3, a plurality of balls 4, a resin retainer 5, and seal rings 6 and 6.
[0021]
The inner ring 2 is provided with a large bulging portion that largely bulges radially outward on one axial side of the outer peripheral surface and a small bulging portion that slightly bulges radially outward on the other axial side. A track groove for the ball 4 is provided in the middle of the direction. At both ends in the axial direction of the inner ring 2, step portions having small diameters are provided.
[0022]
The outer ring 3 is provided with a large bulging portion that largely bulges inward in the radial direction on one side in the axial direction of the inner peripheral surface, and a small bulging portion that slightly bulges inward in the radial direction on the other side in the axial direction. A track groove of the ball 4 is provided in the middle in the axial direction. Large diameter step portions are provided at both axial ends of the outer ring 3.
[0023]
The resin retainer 5 has a shape in which a ball retaining pocket 10 made of a hole penetrating in a direction along the load action line X is provided at several places on the circumference of the ring body. The large ring part 11 arranged at the outer diameter from the virtual cylindrical surface Y, the small ring part 12 arranged at the inner diameter from the virtual cylindrical surface Y, and several circumferential points of the large ring part 11 and the small ring part 12 are connected. Divided into a plurality of cross-linking portions 13. The virtual cylindrical surface Y is obtained by extending the pitch circle diameter of each pocket 10 (diameter of a circle connecting the centers of all pockets 10) in the axial direction, and is indicated by a two-dot chain line in the figure. ing. The bridging portion 13 is inclined from the large ring portion 11 toward the small ring portion 12.
[0024]
A space surrounded by the two large bridging portions 13 adjacent to the large ring portion 11 and the small ring portion 12 in the circumferential direction is the pocket 10. Specifically, the pocket 10 includes a substantially semicircular first recess 14 formed by the large ring portion 11 and each of the two bridging portions 13 adjacent in the circumferential direction, and each of the two small portions 12 adjacent in the circumferential direction. A substantially semicircular second recess 15 made of the bridging portion 13 is combined. The first concave portion 14 and the second concave portion 15 are arranged stepwise in the radial direction.
[0025]
The seal ring 6 is attached to each step portion of the outer ring 3, and forms a contact sealing portion and a non-contact sealing portion with the step portion of the inner ring 2.
[0026]
The resin retainer 5 of this embodiment is configured so that the balls 4 do not come out from the inside of the pocket 10 to the inner diameter side and the outer diameter side, and the ball 4 is incorporated into the pocket 10 by force fitting from the inner diameter side of the pocket 10. It is supposed to be done by. In addition, the resin cage 5 is rotated and guided by a plurality of balls 4 that revolve while rotating in a state where the resin cage 5 is incorporated in the angular ball bearing 1. The position of contact is devised. Such a resin holder 5 will be described in detail below.
[0027]
First, as shown in FIG. 3, the outer diameter of the large ring portion 11 is made thicker than that of the conventional example (the two-dot chain line in FIG. 3), while the inner diameter of the small ring portion 12 is conventionally increased. It is made thinner by making it larger than the example (two-dot chain line in FIG. 3).
[0028]
Next, as shown in FIG. 3, the slope 13a near the large ring portion 11 on the outer diameter surface of the bridging portion 13 is a steep slope inclined at a steep inclination angle θ1 with respect to the virtual cylindrical surface Y, and the small ring portion 12 The close slope 13b is a gentle slope inclined with a gentle inclination angle θ2 with respect to the virtual cylindrical surface Y. By managing the inclination angles θ1 and θ2, the joint 13c between the steep slope 13a and the gentle slope 13b is disposed on the inner diameter side of the virtual conical surface Z1 that connects the large ring portion 11 and the small ring portion 12 with a straight line.
[0029]
On the other hand, the slope 13d near the large ring portion 11 on the inner diameter surface of the bridging portion 13 is a steep slope inclined at substantially the same steep inclination angle θ3 as the steep slope 13a of the outer diameter surface of the bridging portion 13 and 13e is a plane parallel to the virtual cylindrical surface Y. By managing the inner diameter of the flat surface 13d, the joint portion 13f between the steep slope 13d and the flat surface 13e is disposed on the inner diameter side of the virtual conical surface Z2 that connects the large ring portion 11 and the small ring portion 12 with a straight line.
[0030]
Further, as shown in FIG. 4, the first concave portion 14 has a spherical concave surface that is the same as the curvature of the ball 4, and the curvature radius r <b> 1 of the first concave portion 14 is set to be larger than the curvature radius R / 2 of the ball 4. To do.
[0031]
On the other hand, the second concave portion 15 is provided with a spherical concave surface 15a having the same curvature and radius of curvature r2 as the first concave portion 14 in the outer diameter region, and a semi-cylindrical surface 15b in the radial intermediate region, A spherical concave surface 15c having the same radius of curvature r3 as the first concave portion 14 and a center of curvature P shifted α to the inner diameter side is provided in the inner diameter side region. The shift amount α of the center of curvature P of the concave surface 15c on the inner diameter side is set to be the same as the radial length of the semi-cylindrical surface 15b.
[0032]
The deepest viewed from the central axis direction center of the cage at the outer diameter side opening of the said cage center axis from the deepest A1 second recess 15 when viewed from the direction the center of the outer diameter side opening of the first recess 14 a distance W1 to part A2, from the center axis direction center of the cage from the deepest B1 as viewed from the center axis direction center of the cage in the inner diameter side opening of the first recess 14 in the inner diameter side opening of the second recess 15 The interval W2 to the deepest portion B2 as seen is set smaller than the diameter R of the ball 4 and the interval W1 is set smaller than the interval W2.
[0033]
In this embodiment, in the state where the center of the pocket 10 and the center of the ball 4 are matched, the radial gap Δ2 between the inner diameter edge of the second recess 15 and the ball 4 is set to the outer diameter of the first recess 14. It is larger than the radial gap Δ1 between the edge and the ball 4. The radial gap Δ2 is set larger than the diameter expansion amount at the time of thermal expansion based on the material of the resin retainer 5.
[0034]
In the resin cage 5 set in this way, in the process of being rotationally guided by the plurality of balls 4, the deepest portion A1 of the outer diameter side opening of the first recess 14 and the deepest portion of the outer diameter side opening of the second recess 15. Ball 4 comes into contact with A2. Since this contact position is close to a position where the peripheral speed of the ball 4 is small, torque increase and heat generation can be reduced as compared with the conventional example.
[0035]
In the above operation process, the ball 4 does not contact the concave surface 15 c on the inner diameter side of the second concave portion 15. However, when the resin cage 5 swings in the radial direction, the ball 4 may come into contact with the concave surface 15c on the inner diameter side of the second concave portion 15, but the contact is between the spherical surfaces. The movement of 4 is not obstructed.
[0036]
Moreover, in the case of the resin retainer 5 having the above-described configuration, when the diameter is expanded by thermal expansion, the edge of the joint portion 13c on the outer diameter side in the bridging portion 13 is the ball 4 as shown in FIG. On the other hand, at the bridging portion 13, the end edge of the inner diameter side joining portion 13 f approaches the ball 4. However, the radial gap Δ2 on the inner diameter side is larger than the radial gap Δ1 on the outer diameter side, and the radial gap Δ2 on the inner diameter side is set in consideration of the amount of thermal expansion. The end edges B1 and B2 of the joint portion 13f do not contact the ball 4. Therefore, in the resin retainer 5 of this embodiment, even if it thermally expands, it can avoid interfering with the ball 4, so that the rolling of the ball 4 can be smoothed, and an increase in useless torque and heat generation can be suppressed. become.
[0037]
However, the resin retainer 5 is preferably manufactured by injection molding using a material that is difficult to thermally expand, such as PA (polyamide), PEEK (polyetheretheretherketone), or the like. In this injection molding, as shown in FIG. 11, two molds 20 and 21 are used, and after molding, the two molds 20 and 21 are drawn out in directions opposite to each other in the direction of the arrow in the figure, that is, in the axial direction. ing.
[0038]
As described above, when the resin retainer 5 is formed of a material that is difficult to thermally expand, the inner surface of the second recess 15 is a concave surface having a single curvature like the inner surface of the first recess 14, and a radial on the inner diameter side. The gap Δ2 may be set substantially the same as the radial gap Δ1 on the outer diameter side. This case is also included as one embodiment of the present invention.
[0039]
【The invention's effect】
In the resin cage of the present invention, as it is rotated in a state of being incorporated in the angular ball bearing, it is rotated and guided by a plurality of balls that revolve while rotating, but in the process, in the vicinity of a position where the peripheral speed is small Is in contact with the outer diameter side opening of the pocket, so that torque increase and heat generation can be reduced as compared with the conventional example.
[0040]
In addition, the resin cage of the present invention can be thermally expanded because it can prevent the edge of the inner diameter side opening of the pocket approaching the ball from interfering with the ball when the diameter is expanded by thermal expansion. However, it is possible to suppress a useless increase in torque and heat generation, which is preferable.
[0041]
Therefore, the resin cage of the present invention has excellent seizure resistance and is suitable for use at high speed rotation.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an upper half of an angular ball bearing using a resin retainer according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of an upper half showing an exploded state of the angular ball bearing of FIG. 3 is a cross-sectional view showing the upper half of the resin retainer in FIG. 1. FIG. 4 is a cross-sectional view for explaining in detail each part of the resin retainer in FIG. 1. FIG. FIG. 6 is a perspective view of the resin retainer in FIG. 1 as viewed from the large ring side. FIG. 7 is a partial view of the resin retainer in FIG. 1 as viewed from the small ring side. FIG. 8 is a partially developed plan view as seen from the outer diameter side of the resin cage in FIG. 1. FIG. 9 is a developed plan view of a portion as seen from the inner diameter side of the resin cage in FIG. 10 is a cross-sectional view of the upper half showing a state when the resin holder in FIG. 1 is thermally expanded. FIG. 11 is an explanatory view showing a mold for molding the resin holder in FIG. 1 corresponds to FIG. 1. FIG. 13 illustrates a conventional example and corresponds to FIG. 3. FIG. 14 illustrates a conventional example and corresponds to FIG. 5. FIG. 15 illustrates a conventional example and corresponds to FIG. 16 is a diagram corresponding to FIG. 7 in a conventional example. FIG. 17 is a diagram corresponding to FIG. 8 in a conventional example. FIG. 18 is a diagram corresponding to FIG. 9 in a conventional example.
DESCRIPTION OF SYMBOLS 1 Angular contact ball bearing 4 Ball 5 Resin retainer 10 Pocket 11 Large ring part 12 Small ring part 13 Bridging part 14 First recessed part 15 of pocket outer diameter side Second recessed part X of pocket inner diameter side Load acting line

Claims (3)

A resin cage for arranging a plurality of balls provided in an angular ball bearing at predetermined intervals,
A large ring portion having an inner diameter equal to or greater than the circle diameter connecting the centers of the balls, a small ring portion having an outer diameter equal to or less than the circle diameter connecting the centers of the balls, and a plurality of circumferences of the large ring portions and the small ring portions. A ball holding comprising a bridging portion connected to each other, and a hole penetrating in a direction along a load acting line of the angular ball bearing with each of the two bridging portions adjacent to the large ring portion and the small ring portion in the circumferential direction. Make a pocket for
A first recess having a substantially semicircular radial cross section formed by the two large bridging portions adjacent to the large ring portion and the circumferential direction, and two bridging portions adjacent to the small ring portion in the circumferential direction. The radial cross section made of is configured in combination with a substantially semicircular second recess,
The inner surface of the first recess and the inner surface of the second recess are spherical concave surfaces set to the same curvature as the curvature of the ball,
Distance from the deepest viewed from the central axis direction center of the cage in the outer diameter side opening of the first recess to the deepest viewed from the central axis direction center of the cage in the outer diameter side opening of the second recess but smaller than the diameter of the ball, and the central axis of the cage in the inner diameter side opening of the second recess from the deepest viewed from the central axis direction center of the cage in the inner diameter side opening of the first recess It is set smaller than the distance from the center to the deepest part ,
The deepest portion of the junction between the slope near the large ring portion and the slope near the small ring portion on the outer diameter surface of the bridge portion as viewed from the center axial direction center of the cage in the outer diameter side opening of the first recess, A resin retainer that is disposed on the inner diameter side of a virtual conical surface that connects the deepest portion viewed from the center in the central axis direction of the retainer in the outer diameter side opening of the second recess . In a state in which the center of the pocket and the center of the ball coincide with each other, the radial gap between the inner diameter edge of the second recess and the ball has a diameter expansion dimension when the large ring portion and the small ring portion are thermally expanded. The resin retainer according to claim 1 , wherein the resin retainer is set to be larger. The inner surface of the second recess is provided with a spherical concave surface set to the same radius of curvature as the inner surface of the first recess in the outer diameter side region, and a semi-cylindrical surface along the radial direction in the radially intermediate region. provided further, only the outer diameter side radius of curvature of the concave surface same radius of curvature at and center of curvature and the area in the region of the inner diameter side is concave is provided spherical are offset on the inner diameter side, claim 1 or 2 resin cage.

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