CN105782246B - Angular contact ball bearing - Google Patents

Abstract

Angular contact ball bearings can increase the number of balls while ensuring the rigidity of the cage, and improve the axial bearing capacity of the bearing. The first annular portion (31) is provided on the radially outer side of the second annular portion (32). The strut (33) has: an outer diameter side column portion (35) extending axially from the first annular portion to the second annular portion side; extending axially from the second annular portion to the first annular portion side The inner diameter jamb portion (36) is formed by connecting the inner peripheral surface of the outer diameter jamb portion to the outer peripheral surface of the inner diameter jamb portion. The outer peripheral surface of the outer diameter side column part and the edge part (P1) of the axial side surface (35a) of the outer diameter side column part close to the second annular part are located in the axial direction compared with the center (O) of the ball (3). On the side of the second ring part, the inner peripheral surface of the inner diameter side column part and the edge part (P2) of the axial side surface (36a) of the inner diameter side column part close to the first ring part are located in the axial direction compared with the center of the ball. 1st ring part side.

Description

Angular contact ball bearings

technical field

The invention relates to angular contact ball bearings.

Background technique

In CNC lathes, milling machines, machining centers, compound processing machines, five-axis processing machines and other machine tools, electric injection molding machines, punching machines, etc., the spindle box of the punching machine, etc., and the linear feed mechanism of the base on which the workpiece is loaded, use the rotary motion Ball screw converted to linear motion. As a bearing that rotatably supports the shaft end of the ball screw, an angular contact ball bearing is used (for example, refer to Patent Document 1). Among these bearings, bearings having a bearing inner diameter of approximately φ10 mm to φ200 mm are used depending on the size of the headstock of the machine tool used and the base on which the workpiece is loaded.

The cutting load generated during machining, and the inertial load when the headstock and base are moved by rapid acceleration and deceleration are carried as axial loads by angular contact ball bearings via the ball screw. In recent machine tools, there is a tendency that, for the purpose of high-efficiency machining, cutting loads and inertial loads due to rapid feed become large, and large axial loads are carried by angular contact ball bearings.

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

In order to take these into account, either increase the size of the bearing or increase the number of combined rows, but when the bearing size is increased, the space at the shaft end of the ball screw will increase. In addition, when the number of combined rows is excessively increased, the ball The screw unit part will have a wide configuration. As a result, since the required floor area of the machine tool increases and the dimension in the height direction increases, there is a limit in terms of increasing the size of the bearing and increasing the number of rows.

FIG. 12 shows a conventional angular contact ball bearing 100 for supporting a ball screw and a cage 110 used for the angular contact ball bearing 100 . In this angular contact ball bearing 100, by increasing the groove shoulders 101a, 102a on one axial side of the outer ring 101 and on the other axial side of the inner ring 102, and increasing the contact angle of the balls 103, the bearing can be increased. The bearing capacity of the axial load. In addition, in order to avoid interference with the groove shoulders 101a and 102a of the outer ring 101 and the inner ring 102 in the cage 110, a pair of ring parts 111 and 112 are arranged at different heights, and the pair of ring parts are connected by a linear support 113. Section 111, 112.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2000-104742

Contents of the invention

The problem that the present invention intends to solve

Incidentally, in the cage in which the inner surface of the pocket has a spherical shape, the circumferential wall thickness of the strut is smallest at the axially middle portion of the strut. Here, in the cage 110 shown in FIG. 12 , since the struts 113 are formed linearly, it is difficult to ensure the radial thickness of the axially intermediate portions of the struts. Therefore, when trying to ensure the rigidity of the axial middle portion of the support 113 , the number of balls is limited, which may affect the bearing capacity of the axial load of the bearing.

The present invention is made in view of the above circumstances, and an object of the present invention is to provide an angular contact ball bearing capable of increasing the number of balls while ensuring the rigidity of the cage, and improving the bearing capacity in the axial direction of the bearing.

solutions to problems

The above objects of the present invention are achieved by the following configurations.

(1) An angular contact ball bearing comprising:

an outer ring having an outer ring raceway surface on an inner peripheral surface;

an inner ring having an inner ring raceway surface on an outer peripheral surface;

a plurality of balls having a contact angle and freely rolling disposed between the outer ring raceway surface and the inner ring raceway surface; and

A ball-guided retainer, the retainer includes: a first annular portion and a second annular portion arranged at intervals in the axial direction; The plurality of struts arranged at intervals in the direction, the cage has a plurality of pockets, and the plurality of pockets are respectively composed of the struts adjacent in the circumferential direction and the first and second annular portions. portion encloses and holds the plurality of balls separately,

Angular contact ball bearings are characterized by,

On the outer peripheral surface of the inner ring, an inner ring lock is formed on one axial side relative to the inner ring raceway surface, and an inner ring is formed on the other axial side relative to the inner ring raceway surface. Groove shoulder,

On the inner peripheral surface of the outer ring, an outer ring groove shoulder is formed on one axial side relative to the outer ring raceway surface, and an outer ring groove shoulder is formed on the other axial side relative to the outer ring raceway surface. Outer lock,

The contact angle α of the ball is 45°≤α≤70°,

When the result of dividing the radial height He of the groove shoulder of the outer ring by the diameter Da of the ball is Ae (=He/Da), 0.35≤Ae≤0.50,

Assuming that the result of dividing the radial height Hi of the groove shoulder of the inner ring by the diameter Da of the ball is Ai (=Hi/Da), 0.35≤Ai≤0.50,

The first annular portion is disposed radially outward of the second annular portion,

The strut has: an outer diameter side column portion axially extending from the first annular portion toward the second annular portion; an axially extending inner diameter jamb portion, the struts being formed by connecting an inner peripheral surface of the outer diameter jamb portion to an outer peripheral surface of the inner diameter jamb portion,

The outer peripheral surface of the outer diameter side column portion and the edge portion of the axial side surface of the outer diameter side column portion close to the second annular portion are located at the second position in the axial direction compared with the center of the ball. ring part side,

The inner peripheral surface of the inner diameter side column portion and the edge portion of the axial side surface of the inner diameter side column portion close to the first annular portion are positioned on the first circle in the axial direction compared with the center of the ball. ring side.

(2) The angular contact ball bearing according to (1), wherein

The axial side surface of the outer diameter side column portion close to the second annular portion is on the side of the second annular portion compared with the edge portion, and is in contact with the outer peripheral surface of the inner diameter side column portion or the second annular portion. 2. The outer peripheral surface of the annular portion is continuous and formed in a concave cross-section,

The axial side surface of the inner diameter side column part close to the first annular part is on the side of the first annular part compared with the edge part, and the inner peripheral surface of the outer diameter side column part or the The inner peripheral surface of the first annular portion is continuous and formed in a concave cross-section.

(3) The angular contact ball bearing according to (2), wherein

The axial side of the outer diameter side column part close to the second annular part is a partial cylindrical surface with a curvature radius R1 of 0.1×Da≤R1≤2×Da,

The axial side surface of the inner diameter side column portion close to the first annular portion is a partial cylindrical surface with a curvature radius R2 of 0.1×Da≤R2≤2×Da.

(4) The angular contact ball bearing according to any one of (1) to (3), wherein:

The inner diameter of the axial end surface of the first annular portion is larger than the pitch circle diameter of the ball, and the outer diameter of the axial end surface of the second annular portion is smaller than the pitch circle diameter of the ball.

(5) The angular contact ball bearing according to any one of (1) to (4), wherein:

At least the outer diameter side pocket diameter Do formed by the first annular portion and the outer diameter side column portion and the inner diameter side pocket diameter Di formed by the second annular portion and the inner diameter side column portion one smaller than the diameter Da of the ball,

At least one of 0.75×Da≦Do≦0.99×Da and 0.75×Da≦Di≦0.99×Da is satisfied.

(6) The angular contact ball bearing according to any one of (1) to (5), wherein:

The inner surface of the pocket is formed by a spherical portion and a cylindrical portion, wherein the spherical portion is formed on the first annular portion and a part of the outer diameter side column portion continuous from the first annular portion , and the second annular portion and a part of the inner diameter side column portion continuous from the second annular portion, the cylindrical portion is formed on the remaining portion of the outer diameter side column portion, and the inner diameter side column portion the remainder of the jamb section,

A boundary line between the spherical portion and the cylindrical portion of the outer diameter side column portion and a boundary line between the spherical portion and the cylindrical portion of the inner diameter side column portion are located on a virtual line passing through the center of the ball. on flat surface.

(7) The angular contact ball bearing according to any one of (1) to (6), wherein:

The angular contact ball bearing is a double-row angular contact ball bearing configured by combining back surfaces, including: the outer ring having a pair of raceway surfaces of the outer ring; a pair of raceway surfaces of the inner ring respectively the inner ring; and the plurality of balls arranged in double rows between the pair of raceway surfaces of the outer ring and the pair of raceway surfaces of the inner ring.

(8) The angular contact ball bearing according to any one of (1) to (6), wherein:

The angular contact ball bearing is a double-row angular contact ball bearing configured in frontal combination, including: a pair of outer rings respectively having raceway surfaces of the outer ring; a pair of raceway surfaces of the inner ring having a pair the inner ring; and the plurality of balls arranged in double rows between the pair of raceway surfaces of the outer ring and the pair of raceway surfaces of the inner ring.

The effect of the invention

According to the angular contact ball bearing of the present invention, since the contact angle α of the ball is 45°≤α≤70°, increasing the contact angle increases the bearing capacity of the axial load of the bearing, and by setting the contact angle larger, Therefore, a larger preload can be applied, and the rigidity can be further improved. In addition, when the result of dividing the radial height He of the groove shoulder of the outer ring by the diameter Da of the ball is Ae (=He/Da), 0.35≤Ae≤0.50; the radial height of the shoulder of the inner ring groove is When the result of dividing Hi by the diameter Da of the ball is Ai (=Hi/Da), 0.35≤Ai≤0.50, so it is possible to prevent the insufficient bearing capacity of the axial load of the bearing and to easily carry out the shoulder of the inner and outer ring grooves. Grinding.

And, the first annular portion is arranged on the radially outer side of the second annular portion, and the strut has: an outer diameter side column portion extending axially from the first annular portion to the second annular portion side; The inner diameter side column part of the annular part axially extending toward the first annular part side, the strut is formed by connecting the inner peripheral surface of the outer diameter side column part with the outer peripheral surface of the inner diameter side column part, therefore, it is possible to The first annular portion and the second annular portion are arranged at different heights so as to avoid interference with the inner ring groove shoulder and the outer ring groove shoulder.

In addition, the outer peripheral surface of the outer diameter side column portion and the edge portion of the axial side surface of the outer diameter side column portion near the second annular portion are located on the side of the second annular portion in the axial direction compared with the center of the ball; the inner diameter side column Part of the inner peripheral surface and the edge portion of the inner diameter side column portion near the axial side surface of the first annular portion are located on the side of the first annular portion relative to the center of the ball in the axial direction. Accordingly, since the radial thickness of the axially intermediate portion of the strut 33 can be ensured, the circumferential thickness of the axially intermediate portion of the strut 33 can be reduced conversely in order to increase the number of balls. Therefore, the rigidity of the cage can be ensured, the number of balls can be increased, and the axial bearing capacity of the bearing can be improved.

Description of drawings

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

FIG. 2 is a perspective view of the cage of FIG. 1 .

Fig. 3 is a half sectional view of the cage of Fig. 1 .

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

Fig. 5 is a cross-sectional view taken along line V-V in Fig. 3 .

Fig. 6 is a front view of main parts viewed from the direction of arrow VI in Fig. 3 .

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

Fig. 8 is a cross-sectional view illustrating a process of applying a preload to the angular contact ball bearing of Fig. 7 .

9 is a cross-sectional view of an angular contact ball bearing according to a third embodiment of the present invention.

10 is a sectional view of a double row angular contact ball bearing according to Example 1 of the present invention.

11 is a cross-sectional view of a double row angular contact ball bearing according to Example 2 of the present invention.

Fig. 12 is a sectional view of a conventional angular contact ball bearing.

Explanation of reference signs

1 Angular contact ball bearing

3 balls

10 outer ring

11 Outer ring groove shoulder

12 Outer ring lock

20 inner ring

21 Inner ring groove shoulder

22 Inner ring lock

30 cage

31 1st ring part

32 2nd ring part

33 pillars

34 pockets

34a, 34b spherical part

34c, 34d cylindrical part

35 OD Jamb Section

35a axial side

36 ID jamb section

36a axial side

Da Ball diameter

α contact angle

Detailed ways

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

As shown in FIG. 1 , the angular contact ball bearing 1 of this embodiment includes: an outer ring 10 having an outer ring raceway surface 11 on the inner peripheral surface; an inner ring 20 having an inner ring raceway surface 21 on the outer peripheral surface; A plurality of balls 3 disposed between the outer ring raceway surface 11 and the inner ring raceway surface 21 ; and a ball guide type cage 30 that holds the balls 3 in a freely rolling manner.

On the inner peripheral surface of the outer ring 10, an outer ring groove shoulder 12 is formed on the axial side (back side, left side in FIG. 1) with respect to the outer ring raceway surface 11. The other side in the axial direction (the front side, the right side in FIG. 1 ) is formed with an outer ring lock 13 .

On the outer peripheral surface of the inner ring 20 , an inner ring lock 23 is formed on the axial side (back side, left side in FIG. 1 ) with respect to the inner ring raceway surface 21 . On the other side (front side, right side in FIG. 1 ), an inner ring groove shoulder 22 is formed.

Here, when the outer diameter of the lock port 23 of the inner ring is D1, and the outer diameter of the shoulder 22 of the inner ring groove is D2, D1<D2; and the inner diameter of the lock port 13 of the outer ring is D3, and the shoulder of the outer ring groove When the inner diameter of 12 is D4, make D3>D4. In this way, since the outer diameter D2 of the inner ring groove shoulder 22 is increased and the inner diameter D4 of the outer ring groove shoulder 12 is reduced, the contact angle α of the ball 3 can be set larger. 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 it can be 50° even considering the variation of the contact angle α during bearing production. °≤α≤65°, the contact angle α can be increased.

In addition, when the result of dividing the radial height Hi of the inner ring groove shoulder 22 by the diameter Da of the ball 3 is Ai, it is set to satisfy 0.35≤Ai≤0.50; When the result obtained by dividing the height He by the diameter Da of the ball 3 is Ae, it is set to satisfy 0.35≦Ae≦0.50.

Assuming that in the case of 0.35>Ai or 0.35>Ae, since the radial heights Hi and He of the inner ring groove shoulder 22 or outer ring groove shoulder 12 are too small relative to the diameter Da of the ball 3, the contact angle α Less than 45°, the axial load bearing capacity of the bearing is insufficient. In addition, in the case of 0.50<Ai or 0.50<Ae, since the raceway surfaces 11 and 21 of the outer ring 10 and the inner ring 20 are formed beyond the pitch circle diameter dm of the ball 3, the outer ring groove shoulder 12 and the inner ring Grinding of the groove shoulder 22 becomes difficult, which is not desirable.

Next, the configuration of the holder 30 will be described in detail with reference to FIGS. 2 to 6 . The cage 30 is a ball guide type plastic cage made of synthetic resin, and the matrix resin constituting the cage 30 is polyamide resin. In addition, the type of polyamide resin is not limited, and other synthetic resins such as polyacetal resin, polyether ether ketone, polyimide, etc. may be used in addition to polyamide. In addition, glass fiber, carbon fiber, aramid fiber, etc. are added as reinforcing materials to the matrix resin. In addition, the cage 30 is manufactured by injection molding or cutting.

As shown in Fig. 2 and Fig. 3, the cage 30 includes: a first annular portion 31 and a second annular portion 32 arranged at intervals in the axial direction; A plurality of struts 33 arranged at intervals in the circumferential direction between the parts 32 has a plurality of pockets 34, and the plurality of pockets 34 are formed by the adjacent struts 33 in the circumferential direction and the first annular portion 31 and the second annular portion respectively. The portion 32 encloses and holds a plurality of balls 3, respectively.

The first annular portion 31 is provided on the radially outer side of the second annular portion 32 and arranged at different heights so that the first annular portion 31 and the second annular portion 32 are in contact with the inner ring 20 and the inner ring of the outer ring 10 The groove shoulder 22 and the outer ring groove shoulder 12 do not interfere.

The strut 33 has: an outer diameter side column portion 35 extending axially from the first annular portion 31 to the second annular portion 32 side; The extended inner diameter side column portion 36 and the strut 33 are formed such that the inner peripheral surface of the outer diameter side column portion 35 is connected to the outer peripheral surface of the inner diameter side column portion 36 .

Therefore, each pocket hole 34 is formed by the following surfaces: the axial inner surface of the first annular portion 31; the circumferential side surface; the axial inner surface of the second annular portion 32 ;

As shown in FIG. 4 , the axial side surface 35 a of the outer diameter side column portion 35 close to the second annular portion is used to connect the outer peripheral surface of the outer diameter side column portion 35 , the outer peripheral surface of the inner diameter side column portion 36 or the second annular portion. The way in which the outer peripheral surfaces of 32 are connected is formed as a concave cross-section. In addition, the axial side surface 36a of the inner-diameter side column portion 36 close to the first annular portion is also the inner peripheral surface of the inner-diameter side column portion 36, the inner peripheral surface of the outer-diameter side column portion 35, or the first annular portion 31. The manner in which the inner peripheral surfaces are connected is formed in a concave cross-section.

In addition, the outer peripheral surface of the outer diameter side column portion 35 and the edge portion P1 of the axial side surface of the outer diameter side column portion 35 close to the second annular portion 32 are positioned on the second circle in the axial direction compared with the center O of the ball 3 . On the ring portion 32 side, the inner circumferential surface of the inner diameter side column portion 36 and the edge portion P2 of the inner diameter side column portion 36 close to the axial side surface of the first annular portion 31 are located at the first position in the axial direction compared with the center O of the ball 3 . 1 side of the ring part 31.

And, on the side of the second annular portion 32 compared with the edge portion P1, the axial side surface 35a of the outer diameter side column portion 35 formed in a concave cross section and the outer peripheral surface of the inner diameter side column portion 36 or the second circle The outer peripheral surface of the ring portion 32 is continuous.

Similarly, on the side of the first annular portion 31 compared with the edge portion P2, the axial side surface 36a of the inner diameter side column portion 36 formed in a concave cross section and the inner peripheral surface of the outer diameter side column portion 35 or the first The inner peripheral surface of the annular portion 31 is continuous.

In the angular contact ball bearing 1 of this embodiment, in order to avoid interference with the outer ring groove shoulder 12 and the inner ring groove shoulder 22 and to effectively utilize the space between the outer ring 10 and the inner ring 20, the first circular While the ring portion 31 and the second annular portion 32 are arranged with different heights, the first annular portion 31 and the second annular portion 32 are connected by the pillar 33, but it is necessary to avoid the radial direction of the axial middle portion of the pillar 33. The reduction in strength due to thinning of the wall thickness is avoided, and damage to the cage 30 due to stress concentration in the axially intermediate portion is avoided. In particular, if the cage 30 interferes with the outer ring 10 or the inner ring 20, the torque will fluctuate when the cage 30 interferes with the outer ring 10 or the inner ring 20, and accurate positioning cannot be performed as a ball screw system. The friction will wear the cage 30, resulting in damage to the cage 30. In addition, abrasion powder generated when the cage 30 is worn becomes foreign matter, and the lubrication state of the bearing deteriorates, resulting in shortening the life of the bearing.

However, as described above, since the position of the edge P1 between the outer peripheral surface of the outer diameter side column portion 35 and the axial side surface 35a and the edge P2 of the inner peripheral surface of the inner diameter side column portion 36 and the axial side surface 36a Therefore, even if the wall thickness in the circumferential direction is reduced to increase the number of balls, the strength of the axially intermediate portion of the strut 33 can be avoided from being reduced.

In addition, in this 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 partial cylindrical surface whose curvature radius R1 is 0.1×Da≤R1≤2×Da, and the inner diameter side The axial side surface 36a of the column portion 36 close to the first annular portion is also formed by a concave partial cylindrical surface with a curvature radius R2 of 0.1×Da≦R2≦2×Da.

Here, when the radii of curvature R1 and R2 are smaller than 0.1×Da, the outer ring groove shoulder 12 and the inner ring groove shoulder 22 reach the diameter of the pitch circle of the balls, so the contact between the cage 30 and the outer ring 10 or inner ring 20 cannot be avoided. interference. In addition, when the radii of curvature R1 and R2 are greater than 2×Da, the edge P1 between the outer peripheral surface of the outer diameter side column portion 35 and the axial side surface 35a is on the first annular portion side than the axial center, and the inner diameter side column portion 36 Compared with the axial center, the inner peripheral surface and the edge portion P2 of the axial side surface 36a are on the second annular portion side, and the radial wall thickness of the axial middle portion that becomes the minimum wall thickness portion of the strut 33 becomes thinner, which cannot ensure Strength of strut 33.

In addition, it is preferable that the curvature radii R1, R2 of 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 are 0.25×Da≤R1≤1.5×Da, 0.25×Da≤R2≤ 1.5×Da.

In addition, as long as the axial side surface 35 a of the outer diameter side column portion 35 and the axial side surface 36 a of the inner diameter side column portion 36 can avoid stress concentration while avoiding interference between the cage 30 and the outer ring 10 or inner ring 20 , the support can be ensured. The shape of the strength of 33 is sufficient, and it is not limited to a partial cylindrical surface with an arc-shaped cross section, as long as it has a smooth cross-sectional curved surface shape. In addition, the cross-sectional concave shape can also be made by making the plane continuous.

In addition, as shown in Figure 4, the inner diameter D5 of the axial end surface of the first annular portion 31 is greater than the pitch circle diameter P.C.D. of the ball 3, and the outer diameter D6 of the axial end surface of the second annular portion 32 is smaller than the pitch of the ball 3. Circle diameter P.C.D. Thus, it is possible to prevent the inner peripheral surface of the first annular portion 31 and the outer peripheral surface of the second annular portion 32 from colliding with the outer peripheral surface of the opposing inner ring groove shoulder 22 and the inner peripheral surface of the outer ring groove shoulder 12 respectively. interference.

And, the inner peripheral surface of the first annular portion 31 and the outer diameter side column portion 35, and the outer peripheral surface of the second annular portion 32 and the inner diameter side column portion 36 are constituted by gentle inclined surfaces, so that it is easy to mold when injection molding. Axial draw type dies are released in the axial direction. In addition, the inner peripheral surface of the first annular portion 31 and the outer diameter side column portion 35, and the outer peripheral surface of the second annular portion 32 and the inner diameter side column portion 36 may be on a conical surface passing through the center O of the ball 3, Or on a conical surface whose generatrix is parallel to the generatrix of the conical surface.

In addition, in this embodiment, the outer peripheral surface of the first annular portion 31 and the outer diameter side column portion 35 and the inner peripheral surface of the second annular portion 32 and the inner diameter side column portion 36 are formed by a cylinder along the axial direction. face formed.

In addition, as shown in FIG. 5 , the outer diameter side pocket diameter Do formed by the first annular portion 31 and the outer diameter side column portion 35 and the inner diameter side pocket formed by the second annular portion 32 and the inner diameter side column portion 36 At least one of the diameters Di is smaller than the diameter Da of the ball 3 , satisfying at least one of 0.75×Da≦Do≦0.99×Da and 0.75×Da≦Di≦0.99×Da.

Usually, a plurality of angular contact ball bearings 1 are used in combination on the front or back side, but in order to adjust the preload clearance of the bearing, the temporarily assembled bearing is disassembled again, and the end surface of the outer ring 10 or inner ring 20 is adjusted and polished. At this time, when the balls 3 fall out of the pockets 34 of the cage 30 , that is, when the balls 3 are separated from the cage 30 , time is required for assembly.

Therefore, by designing the pocket diameter Do on the outer diameter side and the pocket diameter Di on the inner diameter side as described above, it is possible to prevent the balls 3 from falling out of the pocket holes 34 of the cage 30 . In addition, when both of 0.75×Da≤Do≤0.99×Da and 0.75×Da≤Di≤0.99×Da are satisfied, it is easy to elastically deform the pocket 34 to insert (click insertion, Japanese: パチン insertion) the ball 3 , and the ball 3 will not fall off from the pocket hole 34.

In addition, when the outer ring 10 is disassembled from the angular contact ball bearing 1 to adjust and polish the outer ring 10, at least the pocket diameter Do on the outer diameter side is set to 0.75×Da≤Do≤0.99×Da, so that when adjusting the preload , prevent the ball 3 from coming off from the pocket hole 34.

In addition, 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 pocket diameter Di on the inner diameter side is set to 0.75×Da≤Di≤0.99×Da, so that when adjusting the preload , prevent the ball 3 from coming off from the pocket hole 34.

As shown in Figure 4, the inner surface of the pocket hole 34 is formed by spherical parts 34a, 34b and cylindrical parts 34c, 34d, wherein, the spherical parts 34a, 34b are formed on the first ring part 31 and from the first ring part 31. A part of the continuous outer diameter side column portion 35, and a part of the second annular portion 32 and the inner diameter side column portion 36 continuous from the second annular portion 32, the cylindrical portions 34c, 34d are formed on the outer diameter side column portion 35. the remainder, and the remainder of the inner diameter jamb portion 36 . In addition, the spherical portions 34a, 34b are located on a single spherical surface having a diameter R3 whose center coincides with the center O of the ball 3 .

Also, the boundary line between the spherical portion 34 a and the cylindrical portion 34 c of the outer diameter side column portion 35 and the boundary line between the spherical portion 34 b and the cylindrical portion 34 d of the inner diameter side column portion 36 are located on a virtual plane P passing through the center of the ball 3 . As a result, the mold for forming the spherical portions 34 a and 34 b can be easily released from the axial direction of the pocket 34 . In addition, since the entire inner surface of the pocket 34 is not a spherical surface, but is provided with a cylindrical surface, the interference between the ball 3 and the opening of the pocket can be reduced, and the ball 3 can be easily inserted. In addition, it is easy to discharge the grease in the pocket 34, discharge the excess grease after the grease is enclosed, and facilitate the running-in operation. In addition, when the cage 30 is formed by cutting, a tool such as a ball end mill when finishing the spherical portions 34a and 34b can be easily moved.

In addition, it is preferable that the ratio of the reinforcing material added to the synthetic resin of the cage 30 is 5 to 30 wt%. When the ratio of the reinforcing material exceeds 30 wt%, since the flexibility of the cage 30 decreases, the ball 3 is pressed into the pocket 34 of the cage 30 when the mold is forcibly pulled out from the pocket 34 during cage molding or when the bearing is assembled. , the circumferential edge portion 38 of the cage 30 (the edge portion between the outer peripheral surface of the outer diameter side column portion 35 and the pocket hole 34 , see FIG. 5 ) is damaged.

In addition, when the proportion of the reinforcing material is less than 5 wt%, since the thermal expansion depends on the linear expansion coefficient of the base material, that is, the resin material, the thermal expansion of the cage 30 during the bearing rotation is relatively large relative to the expansion of the pitch circle diameter of the balls, The balls 3 and the pockets 34 of the cage 30 bear against each other, causing bad conditions such as sintering. Therefore, by controlling the ratio of the reinforcing material in the synthetic resin component in the range of 5 to 30 wt%, the above-mentioned troubles can be prevented.

As described above, according to the angular contact ball bearing 1 of the present embodiment, since the contact angle α of the ball 3 is 45°≤α≤70°, increasing the contact angle α increases the bearing capacity of the axial load of the bearing. When the contact angle α is set larger, a larger preload can be applied and the rigidity is further improved. In addition, when the result of dividing the radial height He of the outer ring groove shoulder 12 by the diameter Da of the ball 3 is Ae (=He/Da), 0.35≤Ae≤0.50; suppose the inner ring groove shoulder 22 When the result of dividing the radial height Hi of the ball by the diameter Da of the ball is Ai (=Hi/Da), 0.35≤Ai≤0.50, so it is possible to prevent the insufficient bearing capacity of the axial load of the bearing at the same time, and it is easy to install the inner and outer rings. Grinding of the groove shoulders 22 , 12 .

In addition, the first annular portion 31 is provided on the radially outer side of the second annular portion 32, and the strut 33 has an outer diameter side column portion 35 axially extending from the first annular portion 31 toward the second annular portion. and the inner diameter side column portion 36 extending axially from the second annular portion 32 to the first annular portion side, the strut 33 passes through the inner peripheral surface of the outer diameter side column portion 35 and the outer circumference of the inner diameter side column portion 36 Since the surfaces are connected, the first annular portion 31 and the second annular portion 32 can be arranged at different heights while avoiding interference with the inner ring groove shoulder 22 and the outer ring groove shoulder 12 .

In addition, the outer peripheral surface of the outer diameter side column portion 35 and the edge portion P1 of the axial side surface 35a of the outer diameter side column portion 35 close to the second annular portion are located in the second annular portion relative to the center of the ball 3 in the axial direction. side, the inner peripheral surface of the inner diameter side column portion 36 and the edge portion P2 of the axial side surface 36a of the inner diameter side column portion 36 close to the first annular portion are located on the side of the first annular portion in the axial direction compared with the center of the ball 3 . Thus, since the radial thickness of the axially intermediate portion of the strut 33 can be ensured, the circumferential thickness of the axially intermediate portion of the strut 33 can be reduced in order to increase the number of balls. Therefore, the number of balls can be increased while ensuring the rigidity of the cage 30 , and the axial bearing capacity of the bearing can be improved.

(second embodiment)

Fig. 7 shows a double row angular contact ball bearing 1a according to a second embodiment of the present invention. In addition, the same code|symbol is attached|subjected to the same or equivalent part as 1st Embodiment, and description is abbreviate|omitted or simplified.

As shown in FIG. 7 , in this embodiment, considering the assemblability to a mechanical device, it is a double row angular contact ball bearing arranged in a combination of back faces, and has a single outer ring having a pair of outer ring raceway surfaces 11, 11 10a; a pair of inner rings 20, 20 respectively having inner ring raceway surfaces 21, 21; a plurality of double rows arranged between a pair of outer ring raceway surfaces 11, 11 and a pair of inner ring raceway surfaces 21, 21 balls 3 ; and a ball-guided cage 30 having a plurality of pockets 34 for holding a plurality of balls 3 , respectively. A flange portion 14 for fixing is provided on the outer ring 10 a, and a through-hole 15 for bolting is formed in the flange portion 14 . In addition, an oil groove 16 and an oil hole 17 are formed in an axially intermediate portion of the outer ring 10a, so that grease supply, oil gas, and oil mist can be supplied.

As shown in Figure 8, in order to adjust the preload, an appropriate axial gap δ (usually called the preload gap) is provided between the end faces of the inner ring. After the bearing is installed on the shaft, it is tightened by using the bearing nut ( The end faces of the inner rings are pressed against each other) until the preload gap is 0 (zero), thereby adding preload. In addition, for an appropriate preload gap δ, the outer ring 10, the inner ring 20, the balls 3, and the cage 30 are assembled, the gap is measured, and then disassembled to adjust and polish the inner rings 20, 20. In addition, in the case of increasing the preload, it is only necessary to increase the preload gap.

When the inner ring 20 is disassembled and polished in this way, at least the pocket diameter Di on the inner diameter side is 0.75×Da≤Di≤0.99×Da, thereby preventing the ball 3 from falling out of the pocket hole 34 and shortening the preload adjustment time. The time required for assembly.

Other configurations and functions are the same as those of the first embodiment.

(third embodiment)

9( a ) and ( b ) show a double row angular contact ball bearing 1 b according to a third embodiment of the present invention. In addition, the same code|symbol is attached|subjected to the same or equivalent part as 1st Embodiment, and description is abbreviate|omitted or simplified.

As shown in Figure 9(a), in this embodiment, it is a double-row angular contact ball bearing 1b configured in frontal combination, including: a pair of outer rings 10 respectively having outer ring raceway surfaces 11, 11; A single inner ring 20a for the inner ring raceway surfaces 21, 21; a plurality of balls 3 arranged in double rows between a pair of outer ring raceway surfaces 11, 11 and a pair of inner ring raceway surfaces 21, 21; The cage 30 is a ball guide type retainer 30 that holds a plurality of pockets 34 for holding a plurality of balls 3 .

In this case, the outer rings 10 , 10 are disassembled and the outer rings 10 , 10 are adjusted and polished in order to adjust the preload and obtain an appropriate preload gap between the end faces of the outer rings.

When the outer rings 10, 10 are disassembled and polished in this way, at least the pocket diameter Do on the outer diameter side is set to 0.75×Da≤Do≤0.99×Da, thereby preventing the balls 3 from falling out of the pocket holes 34 and reducing the length of time required. The time required for assembly during pressure adjustment.

Other configurations and functions are the same as those of the first embodiment.

In addition, as shown in FIG. 9( b ), contact type or non-contact type seal members 50 , 50 may be mounted on both axial ends of the outer rings 10 , 10 . Thereby, lubricant such as grease can be held in the bearing space, and intrusion of foreign matter (cutting fluid, chips, etc.) from the outside can be prevented.

In addition, the present invention is not limited to the above-described embodiments, and appropriate modifications, improvements, and the like can be made.

Example 1

FIG. 10 shows Example 1 of the angular contact ball bearing for supporting a ball screw in which the outer ring of the second embodiment is integrated and the inner ring is divided into two. 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 (=radial height He/ball diameter Da of outer ring groove shoulder): 0.38

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

Cage material: polyamide resin

Radius R1 of curvature of the axial side surface 35a of the outer diameter side column portion 35: 0.27×Da (1.7mm)

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

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

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

Example 2

FIG. 11 shows Example 2 of an angular contact ball bearing for supporting a ball screw, in which the outer ring of the second embodiment is integrated and the inner ring is divided into two. In this case, various specifications and dimensions of angular contact ball bearings are set as follows.

Contact angle α: 60°

Ball diameter Da: 7.144mm

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

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

Cage material: Add 10wt% carbon fiber to polyacetal resin as reinforcement material

Radius R1 of curvature of the axial side surface 35a of the outer diameter side column portion 35: 0.90×Da (6.43mm)

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

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

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

The angular contact ball bearings 1a of the first and second examples constituted in this way can achieve the same effects as those of the above-mentioned embodiment.

Claims (9)

1. a kind of angular contact ball bearing, including：

Outer ring, the outer ring have outer ring raceway face on inner peripheral surface；

Inner ring, the inner ring have inner ring raceway face on peripheral surface；

Multiple balls, the multiple ball have contact angle and freely rollably configure in the outer ring raceway face and the inner ring Between roller surface；And

The retainer of ball guidance mode, the retainer include：Justify in axially-spaced spaced 1st annular portion and the 2nd Ring portion；And in multiple pillars of circumferencial direction interval configuration, the retainer between the 1st annular portion and the 2nd annular portion With multiple pocket holes, the multiple pocket hole in the adjacent pillar of circumferencial direction and the 1st annular portion and the 2nd respectively by justifying Ring portion crosses, and keeps the multiple ball respectively,

Angular contact ball bearing is characterized in that,

On the peripheral surface of the inner ring, it is formed with inner ring fore shaft in axial side relative to the inner ring raceway face, relative to The inner ring raceway face is formed with interior ring recess shoulder in the axial other side,

On the inner peripheral surface of the outer ring, it is formed with outer ring recess shoulder in axial side relative to the outer ring raceway face, relatively It is formed with outer ring fore shaft in the axial other side in the inner ring raceway face,

The contact angle α of the ball is 45 °≤α≤70 °,

If be Ae=He/Da by the result after the diameter Da of the radial height He of the outer ring recess shoulder divided by the ball, 0.35≤Ae≤0.50,

If be Ai=Hi/Da by the result after the diameter Da of the radial height Hi of the interior ring recess shoulder divided by the ball, 0.35≤Ai≤0.50,

The radial outside in the 2nd annular portion is arranged in 1st annular portion,

The pillar has：The outer diameter post portion axially extended from the 1st annular portion to the 2nd annular portion side；And The internal diameter post portion axially extended from the 2nd annular portion to the 1st annular portion side, the pillar are by will be described The inner peripheral surface of outer diameter post portion is connected with the peripheral surface of the internal diameter post portion and is formed,

The peripheral surface of the outer diameter post portion and the axial sides close to the 2nd annular portion of the outer diameter post portion Edge is located at the 2nd annular portion side axial compared with the center of the ball,

The inner peripheral surface of the internal diameter post portion and the axial sides close to the 1st annular portion of the internal diameter post portion Edge is located at the 1st annular portion side axial compared with the center of the ball,

The axial sides close to the 2nd annular portion of the outer diameter post portion are compared with the edge in the 2nd annular portion Side, it is continuous with the peripheral surface of the internal diameter post portion or the peripheral surface of the 2nd annular portion, and it is recessed to be formed section Shape,

The axial sides close to the 1st annular portion of the internal diameter post portion are compared with the edge in the 1st annular portion Side, it is continuous with the inner peripheral surface of the outer diameter post portion or the inner peripheral surface of the 1st annular portion, and it is recessed to be formed section Shape.

2. angular contact ball bearing as described in claim 1, which is characterized in that

The axial sides close to the 2nd annular portion of the outer diameter post portion are that radius of curvature R 1 is 0.1 × Da≤R1≤2 The partial cylindrical surface of × Da,

The axial sides close to the 1st annular portion of the internal diameter post portion are that radius of curvature R 2 is 0.1 × Da≤R2≤2 The partial cylindrical surface of × Da.

3. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The internal diameter of the axial end face of 1st annular portion is more than the pitch diameter of the ball, and the axial direction of the 2nd annular portion The outer diameter of end face is less than the pitch diameter of the ball.

4. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The outer diameter side pocket bore Do that formed by the 1st annular portion and the outer diameter post portion and by the 2nd annular portion and At least one diameter Da less than the ball for the internal diameter side pocket bore Di that the internal diameter post portion is formed,

Meet 0.75 × Da≤Do≤0.99 × Da, 0.75 × Da≤Di≤0.99 × Da it is at least one.

5. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The inner surface in the pocket hole is formed by land portions and column part, wherein the land portions are formed in the 1st circle Ring portion and from the 1st annular portion continuously a part for the outer diameter post portion and the 2nd annular portion and from described A part for the continuous internal diameter post portion of 2nd annular portion, the column part are formed in the outer diameter post portion The remainder of remainder and the internal diameter post portion,

The land portions of the outer diameter post portion and the boundary line of the column part and the internal diameter post portion The boundary line of the land portions and the column part is located on the virtual plane by the center of the ball.

6. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The angular contact ball bearing is the double-row angular contact bal bearing to configure with back side combination, including：With a pair of described outer Enclose the outer ring of roller surface；It is respectively provided with a pair inner ring in the inner ring raceway face；And in a pair of outer ring raceway Multiple balls of biserial are configured between face and a pair of inner ring raceway face.

7. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The angular contact ball bearing is the double-row angular contact bal bearing to configure with positive combination, including：It is respectively provided with described outer Enclose a pair outer ring of roller surface；The inner ring with a pair of inner ring raceway face；And in a pair of outer ring raceway Multiple balls of biserial are configured between face and a pair of inner ring raceway face.

8. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The internal diameter of the axial end face of 1st annular portion is more than the pitch diameter of the ball, and the axial direction of the 2nd annular portion The outer diameter of end face is less than the pitch diameter of the ball,

The outer diameter side pocket bore Do that formed by the 1st annular portion and the outer diameter post portion and by the 2nd annular portion and At least one diameter Da less than the ball for the internal diameter side pocket bore Di that the internal diameter post portion is formed,

Meet 0.75 × Da≤Do≤0.99 × Da, 0.75 × Da≤Di≤0.99 × Da it is at least one.

9. angular contact ball bearing as claimed in claim 1 or 2, which is characterized in that

The internal diameter of the axial end face of 1st annular portion is more than the pitch diameter of the ball, and the axial direction of the 2nd annular portion The outer diameter of end face is less than the pitch diameter of the ball,

The inner surface in the pocket hole is formed by land portions and column part, wherein the land portions are formed in the 1st circle Ring portion and from the 1st annular portion continuously a part for the outer diameter post portion and the 2nd annular portion and from described A part for the continuous internal diameter post portion of 2nd annular portion, the column part are formed in the outer diameter post portion The remainder of remainder and the internal diameter post portion,

The land portions of the outer diameter post portion and the boundary line of the column part and the internal diameter post portion The boundary line of the land portions and the column part is located on the virtual plane by the center of the ball.