TW201623819A - Angular contact ball bearing - Google Patents

Abstract

The present invention provides an angular contact ball bearing, which is capable of ensuring the rigidity of a retainer, increasing the amount of balls, and enhancing the loading capability of the bearing in the axial direction. A first annular portion 31 is disposed at a position further outside than a second annular portion 32 in the radial direction. A column portion 33 comprises: an outer diameter side column portion 35 extended along the axial direction from the first annular portion 31 toward the second annular portion; and an inner diameter side column portion 36 extended along the axial direction from the second annular portion 32 toward the first annular portion. The column portion 33 is formed by connecting the inner circumference of the outer diameter side column portion 35 to the outer circumference of the inner diameter side column portion 36. The outer circumference of the outer diameter side column portion 35 and an edge P1 of the outer diameter side column portion 35 near a side 35a of the second annular portion in the axial direction are located closer to the side of the second annular portion in the axial direction than the center O of the ball 3. The inner circumference of the inner diameter side column portion 36 and an edge P2 of the inner diameter side column portion 36 near the side 36a of the first annular portion in the axial direction are located closer to the side of the first annular portion in the axial direction than the center O of the ball 3.

Description

Angular contact ball bearing

This invention relates to angular contact ball bearings.

For NC lathes, milling cutters, automatic tool changer (machining center), multi-tasking machines, five-axis machining machines, etc., or spindle tables for electric injection molding machines, presses, etc. In the direct motion conveying mechanism, a ball screw that converts a rotary motion into a linear motion is used. An angular contact ball bearing is used as a bearing that rotatably supports the shaft end of the ball screw (for example, refer to Patent Document 1). Depending on the size of the spindle table of the working machine used or the frame on which the workpiece is mounted, these bearings are generally used with a bearing inner diameter of approximately Φ10 mm to Φ200 mm.

The cutting load generated during machining or the inertial load when the headstock and the base are moved by the rapid acceleration and the rapid deceleration are used as the axial load load on the angular contact ball bearing via the ball screw. In recent work machines, there is a tendency to increase the inertial load due to cutting load or fast-forwarding for high-efficiency machining purposes, and to apply a large axial load to the bevel ball bearing.

Therefore, in the angular contact ball bearing for supporting such a ball screw, in order to increase the rolling fatigue life, it is necessary to increase both the load capacity in the axial direction and the high rigidity to maintain the machining accuracy.

In order to achieve both of these, it is possible to increase the bearing size or increase the number of combined rows. However, if the bearing size is increased, the space of the ball screw shaft end is increased, and when the number of combined rows is excessively increased, the ball screw unit is formed. The part becomes a composition with a wide width. Result by In order to increase the necessary floor area of the working machine or increase the size of the height direction, the size of the bearing or the number of rows is limited.

Fig. 12 shows the angular contact ball bearing 100 for the previous ball screw support and the holder 110 used for the angular contact ball bearing 100. In the angular contact ball bearing 100, by increasing the shoulder 101a, 102a of the outer side of the outer ring 101 in the axial direction and the other side of the inner ring 102 in the axial direction, the contact angle of the balls 103 is increased, and the axial direction of the bearing can be enhanced. Load capacity of the load. Further, in order to avoid interference between the shoulders 101a and 102a of the outer ring 101 and the inner ring 102, the pair of annular portions 111 and 112 are disposed in a dislocation manner in the holder 110, and the pair is connected by the linear column portion 113. Annular portions 111, 112.

[Previous Technical Literature] [Patent Literature]

[Patent Document]: Japanese Laid-Open Patent Publication No. 2000-104742

However, in the holder having the spherical inner surface of the concave hole, the circumferential wall thickness of the column portion is the thinnest at the intermediate portion in the axial direction of the column portion. Here, in the holder 110 shown in FIG. 12, since the column portion 113 is formed in a straight line shape, it is difficult to secure the radial thickness of the intermediate portion of the column portion in the axial direction. Therefore, if the rigidity of the intermediate portion of the column portion 113 in the axial direction is ensured, the number of balls is limited, which may affect the load capacity of the load in the bearing shaft direction.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an angular contact ball bearing which can secure the rigidity of the retainer and increase the number of balls and improve the load capacity in the bearing shaft direction.

The above object of the present invention is achieved by the following constitution.

(1) An angular contact ball bearing characterized by comprising: The outer ring has an outer ring raceway surface on the inner peripheral surface; the inner ring has an inner ring raceway surface on the outer peripheral surface; and a plurality of balls are rotatably disposed on the outer ring raceway surface and the inner portion at a contact angle And a ball guide type retainer comprising: first and second annular portions which are disposed at intervals of the axial direction; and a plurality of column portions which are equal to the circumferential direction and spaced apart Disposed between the first and second annular portions; and each of the plurality of balls is divided by the column portion adjacent to the circumferential direction and the first and second annular portions, and each of the plurality of balls is held a recessed hole; an inner ring counterbore is formed on one side of the inner ring outer surface of the inner ring in the axial direction with respect to the inner ring raceway surface, and an inner ring shoulder is formed on the other side of the inner ring raceway surface in the axial direction a peripheral portion of the outer ring having an outer ring groove shoulder formed on one side in the axial direction with respect to the outer ring raceway surface, and an outer ring countersunk hole formed on the other side of the outer ring raceway surface in the axial direction The contact angle α of the above ball is 45° ≦α≦70°; When the radial height He of the outer ring groove shoulder is divided by the ball diameter Da, A3 (=He/Da) is 0.35 ≦Ae ≦ 0.50; and the radial height Hi of the inner ring groove shoulder is divided by the above When the ball diameter Da is Ai (=Hi/Da), 0.35≦Ai≦0.50; the first annular portion is provided on the outer side in the radial direction of the second annular portion; and the column portion has the outer diameter side. a column portion extending in the axial direction from the first annular portion toward the second annular portion side; and an inner diameter side column portion extending from the second annular portion toward the first annular portion toward the axial direction The column portion is formed by connecting an inner circumferential surface of the outer diameter side column portion and an outer circumferential surface of the inner diameter side column portion; the outer circumferential surface of the outer diameter side column portion is adjacent to the outer diameter side column portion 2nd An edge portion of the side surface of the annular portion in the axial direction is located closer to the second annular portion side than the center of the ball in the axial direction; and an inner circumferential surface of the inner diameter side column portion is adjacent to the inner diameter side column portion The edge portion of the axial direction side surface of the first annular portion is located closer to the first annular portion side than the center of the ball in the axial direction.

(2) The angular contact ball bearing according to (1), wherein the side surface of the outer diameter side column portion adjacent to the second annular portion is closer to the second annular portion than the edge portion, and continues to the above The outer circumferential surface of the inner diameter side column portion or the outer circumferential surface of the second annular portion is formed in a concave shape in cross section; and the side surface of the inner diameter side column portion closer to the axial direction of the first annular portion is more than the edge portion The inner side surface of the outer diameter side column portion or the inner circumferential surface of the first annular portion is continuous to the first annular portion side, and is formed in a concave shape in cross section.

(3) The angular contact ball bearing of (2), wherein the axial side surface of the outer diameter side post portion adjacent to the second annular portion has a radius of curvature R1 of 0.1 × Da ≦ R1 ≦ 2 × Da The axial side surface of the inner diameter side column portion adjacent to the first annular portion has a curvature radius R2 of a partial cylindrical surface of 0.1 × Da ≦ R2 ≦ 2 × Da.

(4) The angular contact ball bearing according to any one of (1) to (3), wherein an inner diameter of an axial end surface of the first annular portion is larger than a pitch diameter of the ball, and the second annular portion The outer diameter of the end face in the axial direction is smaller than the pitch diameter of the above ball.

(5) The angular contact ball bearing according to any one of (1) to (4), wherein the outer diameter side recess hole diameter Do formed by the first annular portion and the outer diameter side column portion, and At least one of the inner diameter side concave hole diameter Di formed by the second annular portion and the inner diameter side column portion is smaller than the ball diameter Da, and satisfies 0.75 × Da ≦ Do ≦ 0.99 × Da, 0.75 × Da ≦ Di ≦ At least one of 0.99 x Da.

(6) An angular contact ball bearing according to any one of (1) to (5), wherein The inner surface of the recessed hole is formed by a spherical portion including a first annular portion and a portion of the outer diameter side pillar portion continuous from the first annular portion, and the second annular portion and the self The second annular portion is formed by one of the inner diameter side column portions; and the cylindrical portion is formed by the remaining portion of the outer diameter side column portion and the remaining portion of the inner diameter side column portion; A boundary line between the spherical portion of the side post portion and the cylindrical portion, and a boundary line between the spherical portion of the inner diameter side post portion and the cylindrical portion is located on an imaginary plane passing through the center of the ball.

(7) The angular contact ball bearing according to any one of (1) to (6), wherein the angular contact ball bearing is a plurality of angular contact ball bearings arranged in combination with the back surface and comprising: the outer ring having a pair The outer ring raceway surface; the pair of inner rings each having the inner ring raceway surface; and the plurality of balls, wherein the plurality of balls are disposed in a plurality of rows on the pair of outer ring raceways and the pair of inner raceway faces between.

(8) The angular contact ball bearing according to any one of (1) to (6), wherein the angular contact ball bearing is configured by a plurality of rows of angular contact ball bearings disposed on the front side and includes: a pair of the outer rings, respectively The outer ring raceway surface; the inner ring having a pair of inner ring raceways; and a plurality of the balls arranged in a plurality of rows on the pair of outer ring raceways and the pair of inner raceway faces between.

According to the angular contact ball bearing of the present invention, since the contact angle α of the balls is 45° ≦ α ≦ 70°, the contact angle is increased, and the load capacity of the load in the bearing shaft direction is enhanced, and the contact angle can be set to a larger degree. The large preloading load further increases the rigidity. Further, since the radial height He of the outer ring groove shoulder is divided by the ball diameter Da, it is 0.35 ≦Ae ≦ 0.50 when Ae (=He/Da), and the radial height Hi of the inner ring groove shoulder is divided by the ball. When the diameter Da is set to A5 (=Hi/Da), 0.35 ≦ Ai ≦ 0.50, the load capacity of the bearing axial direction load is prevented from being insufficient, and the grinding of the inner and outer ring groove shoulders can be easily performed.

Further, the first annular portion is provided on the outer side in the radial direction of the second annular portion; the column portion has an outer diameter side column portion that extends in the axial direction from the first annular portion toward the second annular portion side; The inner diameter side column portion extends in the axial direction from the second annular portion toward the first annular portion side; since the column portion is connected to the outer circumferential surface of the outer diameter side column portion and the inner diameter side column portion Since it is formed, the first and second annular portions can be arranged in a wrong manner to avoid interference between the inner ring groove shoulder and the outer ring groove shoulder.

Further, the outer peripheral surface of the outer diameter side pillar portion and the edge portion of the outer diameter side pillar portion which are close to the axial side surface of the second annular portion are located closer to the second annular portion side in the axial direction than the center of the ball. The inner peripheral surface of the radial side column portion and the edge portion of the inner diameter side column portion which are close to the axial side surface of the first annular portion are located closer to the first annular portion than the center of the ball in the axial direction. Thereby, since the thickness of the intermediate portion in the axial direction of the column portion can be ensured, in order to increase the number of balls, the circumferential thickness of the intermediate portion in the axial direction of the column portion can be selected. Therefore, the rigidity of the retainer can be ensured, and the number of balls can be increased, thereby improving the load capacity in the direction of the bearing shaft.

1‧‧‧Angle contact ball bearing

1a‧‧‧Multiple angular contact bearings

1b‧‧‧Multiple angular contact bearings

100‧‧‧Angle contact ball bearing

3‧‧‧ balls

10‧‧‧Outer Ring

10a‧‧‧Outer Ring

11‧‧‧Outer ring track surface

12‧‧‧Outer ring shoulder

13‧‧‧ outer ring countersink

14‧‧‧Flange

15‧‧‧through holes

16‧‧‧ oil tank

17‧‧‧ oil hole

20‧‧‧ Inner Ring

21‧‧‧ Inner ring track surface

22‧‧‧Outer ring shoulder

23‧‧‧ Inner ring countersink

30‧‧‧keeper

31‧‧‧1st ring

32‧‧‧2nd ring

33‧‧‧ Column Department

34‧‧‧ recessed hole

34a, 34b‧‧‧ spherical parts

34c, 34d‧‧‧ cylindrical part

35‧‧‧Outer diameter side column section

35a‧‧‧Axis side

36‧‧‧Inside diameter side column section

36a‧‧‧Axis side

50‧‧‧ Sealing members

101‧‧‧Outer Ring

102‧‧‧ Inner Ring

110‧‧‧keeper

101a‧‧‧Slot

102a‧‧‧Slot

111‧‧‧Round Department

112‧‧‧Round Department

113‧‧‧ Column Department

C‧‧‧Roll diameter of the ball

D‧‧‧Roll diameter of the ball

D1‧‧‧ OD

D2‧‧‧ OD

D3‧‧‧Inner diameter

D4‧‧‧Inner diameter

Da‧‧‧Ball diameter

Di‧‧‧ inner diameter side concave hole diameter

Do‧‧‧ outer diameter side recess hole diameter

Hi‧‧‧diameter height

He‧‧‧diameter height

P1‧‧‧Edge

P2‧‧‧Edge

P‧‧‧Roll diameter of the ball

‧‧‧‧contact angle

Fig. 1 is a cross-sectional view showing an angular contact ball bearing according to a first embodiment of the present invention.

Figure 2 is a perspective view of the retainer of Figure 1.

Figure 3 is a half cross-sectional view of the retainer of Figure 1.

Figure 4 is a cross-sectional view taken along line III-III of Figure 2.

Figure 5 is a cross-sectional view taken along line V-V of Figure 3.

Fig. 6 is a front elevational view of a main portion as seen from the direction of arrow VI of Fig. 3.

Figure 7 is a cross-sectional view showing an angular contact ball bearing according to a second embodiment of the present invention.

Figure 8 is a cross-sectional view for explaining a process of imparting a preload to the angular contact ball bearing of Figure 7.

9(a) and 9(b) are cross-sectional views showing an angular contact ball bearing according to a third embodiment of the present invention.

Figure 10 is a cross-sectional view showing a plurality of row angular contact ball bearings of Embodiment 1 of the present invention.

Figure 11 is a cross-sectional view showing a plurality of row angular contact ball bearings of Embodiment 2 of the present invention.

Figures 12(a) and (b) are cross-sectional views of the prior angular contact ball bearings.

Hereinafter, the angular contact ball bearing according to the embodiment of the present invention will be described with reference to the drawings.

(First embodiment)

As shown in Fig. 1, the angular contact ball bearing 1 of the present embodiment includes an outer ring 10 having an outer ring raceway surface 11 on the inner peripheral surface, and an inner ring 20 having an inner ring raceway surface 21 on the outer peripheral surface; The balls 3 are disposed between the outer ring raceway surface 11 and the inner ring raceway surface 21, and the retainer 30 is configured to rotatably hold the balls 3 in a ball guiding manner.

On the inner circumferential surface of the outer ring 10, an outer ring groove shoulder portion 12 is formed on one side (back side, left side in FIG. 1) of the outer ring raceway surface 11 in the axial direction, and the outer ring raceway surface 11 is on the other side in the axial direction. (The front side, the right side in FIG. 1) is formed with an outer ring countersunk hole 13.

On the outer peripheral surface of the inner ring 20, an inner ring countersunk hole 23 is formed on one side (back side, left side in FIG. 1) of the inner ring raceway surface 21 in the axial direction, and the inner ring raceway surface 21 is on the other side in the axial direction (front side) The side, the right side in Fig. 1, is formed with an inner ring groove shoulder 22.

Here, the outer diameter of the inner ring countersunk hole 23 is D1, and when the outer diameter of the inner ring groove shoulder portion 22 is D2, D1 < D2, and the inner diameter of the outer ring countersunk hole 13 is set to D3, the outer ring. When the inner diameter of the groove shoulder portion 12 is D4, D3>D4. Thus, since the outer diameter D2 of the inner ring groove shoulder portion 22 is increased and the inner diameter D4 of the outer ring groove shoulder portion 12 is reduced, the contact angle ? of the balls 3 can be set large. More specifically, by setting the outer diameter D2 and the inner diameter D4 as described above, the contact angle α can be set to about 45° ≦ α ≦ 70°, and even if the deviation of the contact angle α during bearing production is taken into consideration, it may be set. The contact angle α can be increased by about 50° ≦ α ≦ 65°.

Further, when the radial height Hi of the inner ring groove shoulder portion 22 is divided by the diameter Da of the ball 3, A1 is set to satisfy 0.35 ≦ Ai ≦ 0.50; and the outer ring groove shoulder portion 12 is oriented in the radial direction height He. When the diameter Da of the ball 3 is set to Ae, it is set to satisfy 0.35 ≦ Ae ≦ 0.50.

It is assumed that, at 0.35>Ai or 0.35>Ae, since the radial heights Hi and He of the inner ring groove shoulder 22 or the outer ring groove shoulder 12 are too small with respect to the diameter Da of the ball 3, the contact angle α is less than 45°. Insufficient load capacity resulting in load on the bearing shaft. Further, when 0.50 < Ai or 0.50 < Ae, since the raceway faces 11 and 21 of the outer ring 10 and the inner ring 20 are formed to exceed the pitch diameter dm of the balls 3, the outer ring groove shoulder portion 12 and the inner ring groove shoulder portion The grinding of 22 is more difficult and not expected.

Next, the configuration of the holder 30 will be described in detail with reference to Figs. 2 to 6 . The holder 30 is a plastic holder that includes a ball guiding method of synthetic resin, and constitutes a base resin polyamine resin of the holder 30. Further, the type of the polyamide resin is not limited, and other synthetic resins such as polyacetal resin, polyether ether ketone, and polyamidene may be used in addition to the polyamide resin. Further, glass fibers, carbon fibers, aromatic polyamide fibers, and the like as a reinforcing material are added to the base resin. Further, the holder 30 is manufactured by injection molding or cutting.

As shown in FIGS. 2 and 3, the retainer 30 includes first and second annular portions 31 and 32 which are provided at intervals in the axial direction, and a plurality of column portions 33 which are spaced apart from each other in the circumferential direction. The holder 30 is disposed between the first and second annular portions 31 and 32, and the holder 30 is divided by the column portion 33 adjacent to the circumferential direction and the first and second annular portions 31 and 32, respectively. A plurality of recessed holes 34 of a plurality of balls 3 are respectively held.

In order to prevent the first and second annular portions 31 and 32 from interfering with the inner ring groove shoulder portion 22 and the outer ring groove shoulder portion 12 of the inner and outer rings 20 and 10, the first annular portion 31 is provided on the second annular portion. 32 is more outward in the radial direction and is arranged in a wrong distance.

The column portion 33 has an outer diameter side column portion 35 that extends in the axial direction from the first annular portion 31 toward the second annular portion 32 side, and an inner diameter side column portion 36 that faces from the second annular portion 32 The first annular portion 31 side extends in the axial direction, and the column portion 33 is formed to connect the inner circumferential surface of the outer diameter side column portion 35 and the outer circumferential surface of the inner diameter side column portion 36.

Therefore, each of the recessed holes 34 is formed by the inner side surface of the first annular portion 31 in the axial direction and in the first ring The circumferential side surface of one of the pair of outer diameter side column portions 35, the inner side surface of the second annular portion 32 in the axial direction, and the inner side surface of the second annular portion 32 in the axial direction are continuous on both sides of the inner side surface in the axial direction of the portion 31. One of the continuous sides is formed on each of the circumferential inner side faces of the inner diameter side column portion 36.

As shown in Fig. 4, the axial side surface 35a of the outer diameter side column portion 35 close to the second annular portion connects the outer circumferential surface of the outer diameter side column portion 35 with the outer circumferential surface of the inner diameter side column portion 36 or the second ring. The outer peripheral surface of the portion 32 is formed in a concave shape in cross section. Further, the axial side surface 36a of the inner diameter side column portion 36 close to the first annular portion is also connected to the inner circumferential surface of the inner diameter side column portion 36 and the inner circumferential surface or the first annular portion of the outer diameter side column portion 35. The manner of the inner circumference of 31 is formed into a concave shape.

Further, the outer peripheral surface of the outer diameter side pillar portion 35 and the edge portion P1 of the outer diameter side pillar portion 35 which are close to the axial side surface of the second annular portion 32 are located closer to the center O of the ball 3 in the axial direction. 2 the annular portion 32 side; the inner peripheral surface of the inner diameter side column portion 36 and the edge portion P2 of the inner diameter side column portion 36 which is close to the axial side surface of the first annular portion 31 are located in the axial direction with respect to the above-described balls 3 The center O is further on the side of the first annular portion 31.

Further, the axial side surface 35a of the outer diameter side column portion 35 formed in a concave cross section is closer to the second annular portion 32 than the edge portion P1, and continues to the outer circumferential surface or the second circle of the inner diameter side column portion 36. The outer peripheral surface of the ring portion 32.

Similarly, the axial direction side surface 36a of the inner diameter side column portion 36 formed in a concave cross section is closer to the first annular portion 31 side than the edge portion P2, and continues to the inner circumferential surface of the outer diameter side column portion 35 or 1 inner circumferential surface of the annular portion 31.

In the angular contact ball bearing 1 of the present embodiment, in order to avoid interference between the outer ring groove shoulder portion 12 and the inner ring groove shoulder portion 22, and effectively use the space between the outer ring 10 and the inner ring 20, the first position is arranged in a wrong manner. And the second annular portions 31 and 32, and the first and second annular portions 31 and 32 are connected by the column portion 33. However, it is necessary to avoid the strength due to the thickness reduction in the radial direction of the intermediate portion of the column portion 33 in the radial direction. It is lowered, and the damage of the holder 30 due to stress concentration in the axial direction intermediate portion is avoided. In particular, if the retainer 30 interferes with the outer ring 10 or the inner ring 20, the retainer 30 and the outer ring 10 or the inner ring 20 interferes with the torque, so that the correct positioning as the ball screw system cannot be performed. In addition, the friction during the interference causes the retainer 30 to wear, which is related to the damage of the retainer 30. Further, the wear powder generated when the retainer 30 is worn may become a foreign matter, and the lubrication state of the bearing may be deteriorated, resulting in a shortened bearing life.

However, as described above, by setting the position of the outer peripheral surface portion 35 and the edge portion P1 of the axial direction side surface 35a, the inner peripheral surface of the inner diameter side pillar portion 36 and the edge portion P2 of the axial direction side surface 36a. Since the thickness of the intermediate portion in the axial direction of the column portion 33 can be ensured at the position, the thickness of the intermediate portion in the axial direction of the column portion 33 can be prevented from being reduced even if the thickness in the circumferential direction is reduced in order to increase the number of balls.

In the present embodiment, the axial side surface 35a of the outer diameter side column portion 35 close to the second annular portion is formed by a concave cylindrical portion having a curvature radius R1 of 0.1 × Da ≦ R1 ≦ 2 × Da. The axial side surface 36a of the inner diameter side column portion 36 close to the first annular portion is also formed by a concave cylindrical portion having a radius of curvature R2 of 0.1 × Da ≦ R2 ≦ 2 × Da.

Here, if the curvature radii R1, R2 is less than 0.1 × Da, the outer ring groove shoulder portion 12 and the inner ring groove shoulder portion 22 reach the ball pitch circle diameter, so the retainer 30 and the outer ring 10 or the inner ring 20 cannot be avoided. interference. In addition, when the radius of curvature R1, R2 is larger than 0.2 × Da, the outer peripheral side portion 35 and the edge portion P1 of the axial direction side surface 35a are closer to the first annular portion side than the axial center portion, and the inner diameter side column portion The edge portion P2 of the circumferential surface 36 and the axial direction side surface 36a is closer to the second annular portion side than the axial center, and the radial thickness of the axially intermediate portion which is the smallest thickness portion of the column portion 33 is reduced. However, the strength of the column portion 33 cannot be ensured.

Further, it is desirable to set the curvature radii R1, R2 of the axial direction side surface 35a of the outer diameter side column portion 35 and the axial direction side surface 36a of the inner diameter side column portion 36 to 0.25 × Da ≦ R1 ≦ 1.5 × Da, 0.25 × Da ≦ R2 ≦ 1.5 × Da.

Further, the axial side surface 35a of the outer diameter side column portion 35 and the axial side surface 36a of the inner diameter side column portion 36 can prevent the holder 30 from interfering with the outer ring 10 or the inner ring 20, thereby preventing stress concentration and ensuring The shape of the strength of the column portion 33 is not limited to the arcuate portion of the cross section. The cylindrical surface may be a smooth cross-sectional curved shape, or the flat surface may be continuously concave.

Further, as shown in FIG. 4, the inner end surface of the first annular portion 31 in the axial direction is larger than the pitch diameters P, C, and D of the balls 3, and the outer diameter D6 of the axial end faces of the second annular portion 32. It is smaller than the pitch diameters P, C, and D of the balls 3. Thereby, it is possible to prevent the inner circumferential surface of the first annular portion 31 and the outer circumferential surface of the second annular portion 32 from respectively, and the outer circumferential surface of the inner circumferential groove portion 22 and the inner circumferential surface of the outer ring groove shoulder portion 12 interference.

Further, in order to facilitate the axial drawing of the axial mold in the axial direction during the injection molding, the inner circumferential surface of the first annular portion 31 and the outer diameter side column portion 35 and the second annular portion 32 and the inner portion The outer peripheral surface of the radial side column portion 36 is constituted by a gently inclined surface. Further, the inner circumferential surface of the first annular portion 31 and the outer diameter side column portion 35 and the outer circumferential surfaces of the second annular portion 32 and the inner diameter side column portion 36 may be located on a conical surface passing through the center O of the ball 3. Or a conical surface parallel to the busbar of the conical surface.

In the present embodiment, the outer circumferential surface of the first annular portion 31 and the outer diameter side column portion 35 and the inner circumferential surface of the second annular portion 32 and the inner diameter side column portion 36 are cylindrical along the axial direction. Face formation.

Further, as shown in FIG. 5, the outer diameter side concave hole diameter Do formed by the first annular portion 31 and the outer diameter side column portion 35, and the second annular portion 32 and the inner diameter side column portion 36 are formed. At least one of the inner diameter side concave hole diameters Di is smaller than the diameter Da of the balls 3, and satisfies at least one of 0.75 × Da ≦ Do ≦ 0.99 × Da, 0.75 × Da ≦ Di ≦ 0.99 × Da.

The angular contact ball bearing 1 is usually used by combining a plurality of front or back faces. However, in order to adjust the preload clearance of the bearing, the temporarily assembled bearing is re-decomposed, and the end face of the outer ring 10 or the inner ring 20 is adjusted and ground. At this time, in the case where the ball 3 is detached from the recessed hole 34 of the retainer 30, that is, when the ball 3 is separated from the retainer 30, it takes time to assemble.

Therefore, by designing the outer diameter side recessed hole diameter Do and the inner diameter side recessed hole diameter Di as described above, it is possible to prevent the balls 3 from coming off the recessed holes 34 of the retainer 30. In addition, it satisfies 0.75×Da≦ When Do ≦ 0.99 × Da, 0.75 × Da ≦ Di ≦ 0.99 × Da, the balls 3 are easily elastically deformed by the concave holes 34 to be inserted (snap-inserted), and the balls 3 are not detached from the concave holes 34.

Further, when the outer ring 10 is disassembled from the angular contact ball bearing 1 and the outer ring 10 is subjected to the adjustment polishing, at least the outer diameter side recessed hole diameter Do is set to 0.75 × Da ≦ Do ≦ 0.99 × Da, and is preloaded. When the adjustment is made, the balls 3 can be prevented from falling off from the recessed holes 34.

Further, when the inner ring 20 is disassembled from the angular contact ball bearing 1 and the inner ring 20 is adjusted and polished, at least the inner diameter side recessed hole diameter Di is set to 0.75 × Da ≦ Di ≦ 0.99 × Da, and the preload is applied. When the adjustment is made, the balls 3 can be prevented from falling off from the recessed holes 34.

As shown in Fig. 4, the inner surface of the recessed hole 34 is formed by a spherical portion 34a, 34b which is equal to the first annular portion 31 and the outer diameter side column portion 35 which is continuous from the first annular portion 31. a portion and a portion of the second annular portion 32 and one of the inner diameter side column portions 36 continuous from the second annular portion 32; and cylindrical portions 34a, 34d which are the remainder of the outer diameter side column portion 35 and the inner diameter The remainder of the side post portion 36 is formed. Further, the spherical portions 34a, 34b are located on a single spherical surface of the diameter R3 whose center coincides with the center O of the balls 3.

Further, the boundary line between the spherical portion 34a of the outer diameter side column portion 35 and the cylindrical portion 34c, and the boundary line between the spherical portion 34b of the inner diameter side column portion 36 and the cylindrical portion 34d are located on the imaginary plane P passing through the center of the ball 3. Thereby, in the recessed holes 34, the mold drawing of the forming spherical portions 34a and 34b can be easily performed from the axial direction. Further, the entire inner surface of the recessed hole 34 is not formed as a spherical surface, and by being a cylindrical surface, the interference portion between the ball 3 and the opening of the recessed hole can be narrowed, so that the ball 3 can be easily inserted. Further, the grease in the recessed holes 34 is easily discharged, so that the excess grease sealed in the grease can be discharged, and the inertia operation can be easily performed. Further, when the retainer 30 is formed by cutting, the movement of the tool such as the ball end mill when performing the finishing processing of the spherical portions 34a and 34b can be easily performed.

Further, the proportion of the reinforcing material added to the synthetic resin of the holder 30 is preferably from 5 to 30% by weight. When the ratio of the reinforcing material exceeds 30% by weight, since the flexibility of the retainer 30 is lowered, when the mold is forcibly pulled out from the recessed portion 33 at the time of forming the retainer, or when the bearing is assembled, When the ball 3 is pressed into the recessed hole 34 of the retainer 30, the circumferential edge portion 38 of the retainer 30 (the outer peripheral surface of the outer diameter side post portion 35 and the edge portion of the recessed hole 34, see FIG. 5) is broken.

Further, if the proportion of the reinforcing material is less than 5% by weight, since the thermal expansion depends on the linear expansion coefficient of the base material, that is, the resin material, the thermal expansion of the retainer 30 during the bearing rotation relatively increases the diameter of the ball pitch circle, resulting in the ball. 3 is in contact with the recessed portion 34 of the holder 30 to cause defects such as scorching. Therefore, the above-mentioned defects can be prevented by setting the ratio of the reinforcing material in the synthetic resin component to a range of 5 to 30% by weight.

As described above, according to the angular contact ball bearing of the present embodiment, since the contact angle α of the balls 3 is 45° ≦ α ≦ 70°, the contact angle α is increased, and the load capacity of the load in the bearing shaft direction is enhanced by The earth set the contact angle α to give a larger preload load and further increase the rigidity. Further, when the radial height He of the outer ring groove shoulder portion 12 is divided by the diameter Da of the ball 3, it is 0.35 ≦Ae ≦ 0.50 when Ae (=He/Da), and the radial direction of the inner ring groove shoulder portion 22 is obtained. When the height Hi is divided by the diameter Da of the ball, it is 0.35 when it is set to Ai (=Hi/Da). Ai Since 0.50, the load capacity for preventing the load in the bearing shaft direction is insufficient, and the grinding processing of the inner and outer ring groove shoulders 22, 12 can be easily performed.

Further, the first annular portion 31 is provided on the outer side in the radial direction of the second annular portion 32, and the column portion 33 has the outer diameter side column portion 35 from the first annular portion 31 toward the second annular portion side. The inner diameter side column portion 36 extends in the axial direction from the second annular portion 32 toward the first annular portion side; since the column portion 33 is connected to the inner peripheral surface of the outer diameter side column portion 35 Since the outer circumferential side column portion 36 is formed on the outer circumferential surface, the first and second annular portions 31 and 32 can be disposed in a wrong manner to avoid interference between the inner ring groove shoulder portion 22 and the outer ring groove shoulder portion 12.

Further, the outer peripheral surface of the outer diameter side column portion 35 and the edge portion P1 of the outer diameter side column portion 35 which is close to the axial direction side surface 35a of the second annular portion are located second to the center of the ball 3 in the axial direction. On the side of the ring portion, the inner peripheral surface of the inner diameter side column portion 36 and the edge portion P2 of the inner diameter side column portion 36 which are close to the axial side surface 36a of the first annular portion are located at the center of the ball 3 in the axial direction. It is on the side of the first ring. Thereby, the intermediate portion of the axial direction of the column portion 33 can be ensured. Since the thickness is thick in the radial direction, in order to increase the number of balls, the circumferential thickness of the intermediate portion of the column portion 33 in the axial direction can be reduced. Therefore, the rigidity of the retainer 30 can be ensured, and the number of balls can be increased, and the load capacity in the direction of the bearing shaft can be improved.

(Second embodiment)

Fig. 7 shows a plurality of row angular contact ball bearings 1a according to a second embodiment of the present invention. The same or equivalent portions as those in the first embodiment are denoted by the same reference numerals, and their description is omitted or simplified.

As shown in Fig. 7, in view of the assemblability of the mechanical device, the present embodiment is a plurality of angular contact ball bearings arranged in combination on the back side, comprising: a single outer ring 10a having an outer ring raceway surface 11 And a pair of inner rings 20 and 20 respectively having inner ring race faces 21 and 21; and a plurality of balls 3 disposed in a plurality of rows on a pair of outer ring race faces 11, 11 and a pair of inner ring race faces 21, And a ball guide type holder 30 having a plurality of recessed holes 34 for holding a plurality of balls 3, respectively. A flange portion 14 for fixing is provided in the outer ring 10a, and a through hole 15 for bolt fastening is formed in the flange portion 14. Further, an oil groove 16 and an oil hole 17 are formed in the intermediate portion of the outer ring 10a in the axial direction, thereby providing supply of grease or supply of oil and gas and oil mist.

As shown in Fig. 8, in order to adjust the preloading load, an appropriate axial clearance δ (commonly referred to as preloading clearance) is provided between the end faces of the inner ring. After the bearing is mounted to the shaft, the bearing nut is used to lock to The pre-pressure play becomes 0 (zero) (the inner ring end faces are made to be close to each other), and the preload is added. Further, the outer ring 10, the inner ring 20, the balls 3, and the retainer 30 are assembled by the appropriate pre-pressure clearance δ, and the clearance is measured, and then the inner ring 20 and 20 are adjusted and ground. In addition, when the preload is increased, it is only necessary to increase the preload.

When the inner ring 20 is decomposed and adjusted and polished, at least the inner diameter side recessed hole diameter Di is set to 0.75 × Da ≦ Di ≦ 0.99 × Da, whereby the balls 3 can be prevented from falling off from the recessed holes 34. Reduce the time required for assembly during preload adjustment.

Other configurations and operations are the same as those in the first embodiment.

(Third embodiment)

Fig. 9 (a) and (b) show a plurality of row angular contact ball bearings 1b according to a third embodiment of the present invention. The same or equivalent portions as those in the first embodiment are denoted by the same reference numerals, and their description is omitted or simplified.

As shown in Fig. 9(a), the present embodiment is a plurality of row angular contact ball bearings 1b arranged in a front combined configuration, comprising: an outer ring 10 having outer ring race faces 11, 11 respectively; a single inner ring 20a, having a pair of inner ring track faces 21, 21; a plurality of balls 3 arranged in a plurality of rows between a pair of outer ring track faces 11, 11 and a pair of inner ring track faces 21, 21; and ball guiding mode The holder 30 has a plurality of recesses 34 for holding a plurality of balls 3, respectively.

In this case, in order to adjust the preloading load, an appropriate pre-pressure clearance is obtained between the end faces of the outer ring, the outer rings 10, 10 are disassembled, and the outer rings 10, 10 are adjusted and ground.

When the outer rings 10 and 10 are disassembled and adjusted and polished, at least the outer diameter side recessed hole diameter Do is set to 0.75 × Da ≦ Do ≦ 0.99 × Da, whereby the balls 3 can be prevented from falling off from the recessed holes 34. This reduces the time required for assembly during preload adjustment.

Other configurations and operations are the same as those in the first embodiment.

Further, as shown in FIG. 9(b), the contact members or non-contact type sealing members 50, 50 may be attached to both end portions of the outer rings 10, 10 in the axial direction. Thereby, a lubricant such as grease can be held in the bearing space, and entry of foreign matter (cutting fluid, cutting powder, etc.) from the outside can be prevented.

Further, the present invention is not limited to the above embodiment, and can be appropriately changed or improved.

[Example 1]

Fig. 10 is a view showing a first embodiment of an angular contact ball bearing for ball screw support in which the outer ring-integrated inner ring is divided into two according to the second embodiment. In this case, various specifications and dimensions of the angular contact ball bearing are set as follows.

Contact angle α: 50°

Ball diameter Da: 6.35mm

Ae (= diameter of the outer ring groove shoulder height He / ball diameter Da): 0.38

Ai (= diameter of the inner ring groove shoulder Hi / ball diameter Da): 0.38

Retainer material: Polyamide resin

Curvature radius R1 of the axial direction side surface 35a of the outer diameter side pillar portion 35: 0.27 × Da (1.7 mm)

The radius of curvature R2 of the axial side surface 36a of the inner diameter side column portion 36: 0.27 × Da (1.7 mm)

Outer diameter side concave hole diameter φDo: 0.80 × Da (5.08mm)

Inner diameter side concave hole diameter φDi: 0.80 × Da (5.08mm)

[Embodiment 2]

Fig. 11 is a view showing a second embodiment of an angular contact ball bearing for ball screw support in which the outer ring-integrated inner ring is divided into two according to the second embodiment. In this case, various specifications and dimensions of the angular contact ball bearing are set as follows.

Contact angle α: 60°

Ball diameter Da: 7.144mm

Ae (= diameter of the outer ring groove shoulder height He / ball diameter Da): 0.47

Ai (= diameter of the inner ring groove shoulder Hi / ball diameter Da): 0.47

Retainer material: 10% by weight of carbon fiber added to the polyacetal resin as a reinforcing material

Curvature radius R1 of the axial direction side surface 35a of the outer diameter side pillar portion 35: 0.90 × Da (6.43 mm)

The radius of curvature R2 of the axial side surface 36a of the inner diameter side column portion 36: 0.90 × Da (6.43 mm)

Outer diameter side concave hole diameter φDo: 0.90 × Da (6.43mm)

Inner diameter side concave hole diameter φDi: 0.90 × Da (6.43mm)

The angular contact ball bearing 1a of the first embodiment and the second embodiment configured as described above can exhibit the same effects as those of the above embodiment.

1‧‧‧Angle contact ball bearing

3‧‧‧ balls

10‧‧‧Outer Ring

11‧‧‧Track surface

12‧‧‧Outer ring shoulder

13‧‧‧ outer ring countersink

20‧‧‧ Inner Ring

21‧‧‧ Inner ring track surface

22‧‧‧ Inner ring shoulder

23‧‧‧ Inner ring countersink

30‧‧‧keeper

31‧‧‧1st ring

32‧‧‧2nd ring

Da‧‧‧Ball diameter

D1‧‧‧ OD

D2‧‧‧ OD

D3‧‧‧Inner diameter

D4‧‧‧Inner diameter

He‧‧‧diameter height

Hi‧‧‧diameter height

Claims (8)

An angular contact ball bearing, comprising: an outer ring having an outer ring raceway surface on an inner circumferential surface; an inner ring having an inner ring raceway surface on the outer circumferential surface; a plurality of balls, which are rolled freely at a contact angle Arranging between the outer ring raceway surface and the inner ring raceway surface; and a ball guide type retainer, comprising: first and second annular portions, which are disposed at intervals corresponding to an axial direction; and a plurality of a column portion disposed between the first and second annular portions at intervals in the circumferential direction; and having the column portions adjacent to each other in the circumferential direction and the first and second annular portions respectively Dividing and holding a plurality of concave holes of the plurality of balls respectively; forming an inner ring countersunk hole on one side of the inner ring orbital surface on the outer circumferential surface of the inner ring, relative to the inner ring orbital surface An inner ring groove shoulder portion is formed on the other side of the axial direction; an outer ring groove shoulder portion is formed on an inner circumferential surface of the outer ring on the axial direction side of the outer ring raceway surface with respect to the inner ring raceway surface The outer side of the shaft is formed with an outer ring buried head The contact angle α of the ball is 45°≦α≦70°; when the radial height He of the outer ring groove shoulder is divided by the ball diameter Da, A3 (=He/Da) is set, 0.35≦Ae≦0.50. And when the radial height Hi of the inner ring groove shoulder is divided by the ball diameter Da, A3 (=Hi/Da) is 0.35≦Ai≦0.50; and the first annular portion is provided in the second circle The ring portion is more outward in the radial direction; the column portion has an outer diameter side column portion extending in the axial direction from the first annular portion toward the second annular portion side, and an inner diameter side column portion from the above Second ring a portion extending toward the axial direction toward the first annular portion side, wherein the column portion is formed by connecting an inner circumferential surface of the outer diameter side column portion and an outer circumferential surface of the inner diameter side column portion; and the outer diameter side column portion An outer peripheral surface and an edge portion of the outer diameter side pillar portion that is closer to the axial side surface of the second annular portion are located closer to the second annular portion than the center of the ball in the axial direction; and the inner diameter An edge portion of the inner circumferential surface of the side column portion and the side surface of the inner diameter side column portion adjacent to the axial direction of the first annular portion is located closer to the first annular portion than the center of the ball in the axial direction. The angular contact ball bearing according to claim 1, wherein the side surface of the outer diameter side column portion adjacent to the second annular portion is closer to the second annular portion than the edge portion, and continues to the inner diameter side The outer circumferential surface of the column portion or the outer circumferential surface of the second annular portion is formed in a concave shape in cross section; and the side surface of the inner diameter side column portion adjacent to the axial direction of the first annular portion is further than the edge portion The first annular portion side is continuous to the inner circumferential surface of the outer diameter side column portion or the inner circumferential surface of the first annular portion, and is formed in a concave shape in cross section. The angular contact ball bearing of claim 2, wherein the axial side surface of the outer diameter side post portion adjacent to the second annular portion has a radius of curvature R1 of 0.1×Da≦R1≦2×Da; The axial side surface of the inner diameter side pillar portion close to the first annular portion has a curvature radius R2 of a partial cylindrical surface of 0.1 × Da ≦ R2 ≦ 2 × Da. The angular contact ball bearing according to any one of claims 1 to 3, wherein an inner diameter of the axial end surface of the first annular portion is larger than a pitch diameter of the ball, and an axial end surface of the second annular portion The outer diameter is smaller than the pitch diameter of the above balls. The angular contact ball bearing according to any one of claims 1 to 4, wherein the outer diameter side concave opening formed by the first annular portion and the outer diameter side column portion The diameter Do and at least one of the inner diameter side recess hole diameters Di formed by the second annular portion and the inner diameter side column portion are smaller than the diameter Da of the ball, and satisfy 0.75 × Da ≦ Do ≦ 0.99 × Da At least one of 0.75 × Da ≦ Di ≦ 0.99 × Da. The angular contact ball bearing according to any one of claims 1 to 5, wherein the inner surface of the recessed hole is formed by a spherical portion which is continuous by the first annular portion and the first annular portion a portion of the outer diameter side column portion and a portion of the second annular portion and the inner diameter side column portion continuous from the second annular portion; and a cylindrical portion which is surrounded by the outer diameter side column portion a portion and a remaining portion of the inner diameter side pillar portion; and a boundary line between the spherical portion of the outer diameter side pillar portion and the cylindrical portion, and a boundary line between the spherical portion and the cylindrical portion of the inner diameter side pillar portion Located on the imaginary plane passing through the center of the above ball. The angular contact ball bearing according to any one of claims 1 to 6, wherein the angular contact ball bearing is a plurality of angular contact ball bearings arranged in combination on the back side, and includes: the outer ring having a pair of the outer ring tracks a pair of inner rings each having the inner ring raceway surface; and a plurality of the balls disposed between the pair of outer ring raceways and the pair of inner raceway faces in a plurality of rows. The angular contact ball bearing according to any one of claims 1 to 6, wherein the angular contact ball bearing is a plurality of angular contact ball bearings arranged in combination on the front side, and includes: a pair of the outer rings, each having the outer ring a raceway surface; the inner ring having a pair of inner ring raceways; and a plurality of the balls disposed between the pair of outer raceway faces and the pair of inner raceway faces in a plurality of rows.