WO2019044528A1

WO2019044528A1 - Angular ball bearing, bearing device, and spindle device

Info

Publication number: WO2019044528A1
Application number: PCT/JP2018/030451
Authority: WO
Inventors: 和巳岩▲崎▼; 美昭勝野
Original assignee: 日本精工株式会社
Priority date: 2017-09-01
Filing date: 2018-08-16
Publication date: 2019-03-07
Also published as: KR20200032201A; KR102355566B1

Abstract

In an inner ring (12), a counter bore (12b) is formed on the bearing back side with respect to an inner ring raceway surface (12a), and the minimum outer diameter (D1) of the counter bore (12b) is smaller than the outer diameter (D) of a shoulder portion (12c) on the bearing front side with respect to the inner ring raceway surface (12a). In addition, a sealing member (15) fixed to the bearing back side of an outer ring (11) is provided with: a disk portion (23); and at least one annular inclined portion (24) that is inclined toward the center of an angular ball bearing (10) in the axial direction, while extending from the disk portion (23) toward the radially inner side. The maximum diameter (D4) of the inclined portion (24) on the axially inner surface side of the sealing member (15) is smaller than the inner diameter (D5) of a holder (14) on a bearing back side end surface (14b). The maximum diameter (D3) of the inclined portion (24) on the axially outer side of the sealing member (15) is larger than the outer diameter (D) of the shoulder portion (12c) on the bearing front side of the inner ring (12) in the angular ball bearing (10).

Description

Angular contact ball bearings, bearing devices, and spindle devices

The present invention relates to an angular ball bearing, a bearing device, and a spindle device, and in particular, an angular motor applied to a spindle of a cutting machine tool (a lathe, a milling machine, a machining center, etc.), a spindle of a grinding machine, a high frequency spindle, etc. The present invention relates to a ball bearing, a bearing device, and a spindle device.

In order to satisfy the required characteristics such as rolling fatigue life and high rigidity, a main shaft of a machine tool employs a bearing arrangement in which a plurality of cylindrical roller bearings and angular ball bearings are used. In particular, grease filled angular contact ball bearings are often used for high-speed spindle devices such as high-frequency spindles and grinding machines. A seal member is attached to such an angular contact ball bearing to prevent scattering of grease to the outside and intrusion of cutting fluid from the outside (see, for example, Patent Document 1).

Further, as a seal member provided in the ball bearing, grease is effectively adhered to the seal member to reduce torque, and the inner and outer ring shoulders corresponding to the inner and outer peripheral end portions of the seal member are faced What provided the inclination part which inclines is disclosed (for example, refer patent document 2). Furthermore, as a ball bearing, a bearing provided with a seal member in which an inner end portion is bent and formed is known (see, for example, Patent Documents 3 and 4).

Japanese Patent Application Laid-Open No. 2006-46609 Japanese Patent Application Laid-Open No. 2003-336650 Japanese Patent Application Laid-Open No. 2005-291304 Japanese Patent Laid-Open No. 11-287255

As a conventional spindle device, an air flow path for air purge opened in a gap between the housing and the rotation shaft is provided on the side of the bearing to prevent the entry of dust such as cutting water or chips into the bearing. It is known.

FIG. 18 is a cross-sectional view of a spindle device in which conventional angular ball bearings are combined in parallel as a front bearing. In the spindle device 100, a part of the air supplied from the air purge air flow path 155 formed in the housing 152 flows into the pair of angular contact ball bearings 110 combined in parallel. In the angular contact ball bearing 110, there is a possibility that the seal member 115 provided on the bearing back side may be deformed by the air, in which case the inner ring 112 of the adjacent angular contact ball bearing 110 and the step portion 143 of the rotating shaft 141 make contact. As a result, problems such as an increase in torque and damage to the seal member 115 may occur.

In addition, the seal member 115 may be inclined due to mounting displacement to the seal groove, a caulking error in the case of a metal seal, or the like in the seal member 115 mounted on the angular ball bearing 110. For this reason, the seal member 115 provided on the bearing rear surface side may come into contact with the inner ring 112 of the adjacent angular ball bearing 110 and the step portion 143 of the rotary shaft 141 also by the mounting factor of the seal member 115.

On the other hand, it is also conceivable to prevent the contact between the seal member and the inner ring of the adjacent bearing by setting the entire seal member further inside (parallel movement in the axial center direction of the bearing). May interfere with the cage.

In the ball bearings described in Patent Documents 2 to 4, although the inclined portion is provided at the inner and outer peripheral end of the seal member or the inner end of the seal member, the bending position of the inclined portion is specifically specified No consideration is given to contact with the cage or adjacent members.

The present invention has been made in view of the above-described problems, and its object is to ensure that the seal member comes in contact with a member adjacent to the inner ring such as the inner ring or inner ring spacer of the adjacent bearing and the retainer. It is an object of the present invention to provide an angular contact ball bearing, a bearing device, and a main shaft device capable of preventing the air flow, in particular, preventing air flow from flowing into the bearing by air purge.

The above object of the present invention is achieved by the following constitution.
(1) The outer ring having an outer ring raceway surface on the inner circumferential surface, the inner ring having an inner ring raceway surface on the outer peripheral surface, and the outer ring raceway surface and the inner ring raceway surface are rollably disposed with a predetermined contact angle. A plurality of balls, a cage rotatably holding the plurality of balls, and a noncontact seal member provided on at least a bearing back side to cover an opening between the outer ring and the inner ring; An angular contact ball bearing comprising
In the inner ring, a counter bore is formed on the bearing rear surface side with respect to the inner ring raceway surface, and the minimum outer diameter of the counter bore is the outside of a shoulder provided on the bearing front side with respect to the inner ring raceway surface. Smaller than the diameter,
The seal member fixed to the bearing rear surface side of the outer ring is at least a disc portion and at least a linear or curved slope toward the axial center of the angular ball bearing as it goes radially inward from the disc portion With one annular ramp,
The maximum diameter of the inclined portion on the inner surface side in the axial direction of the seal member is smaller than the inner diameter of the end face on the bearing back side of the cage,
The angular ball bearing according to claim 1, wherein the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member is larger than the outer diameter of the shoulder portion on the bearing front side of the inner ring.
(2) The angular ball according to (1), wherein the maximum diameter of the inclined portion on the inner surface side in the axial direction of the seal member is larger than the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member. bearing.
(3) The angular ball bearing according to (1) or (2), wherein the retainer and the inclined portion of the seal member overlap when viewed from the radial direction.
(4) The angular ball bearing according to (1) or (2), wherein the cage and the inclined portion of the seal member are separated in the axial direction.
(5) A plurality of the angular contact ball bearings according to any one of (1) to (4),
A bearing device characterized in that the plurality of angular contact ball bearings are combined in parallel.
(6) The bearing device according to (5), further including the angular ball bearing back-mounted to the plurality of angular ball bearings coupled in parallel.
(7) The bearing device according to (5), further including the angular ball bearing that is combined frontally with respect to the plurality of angular ball bearings that are combined in parallel.
(8) The angular ball bearing according to any one of (1) to (4),
An annular member disposed adjacent to the bearing back side of the angular ball bearing,
Equipped with
The maximum diameter of the inclined portion on the axial outer surface side of the seal member is larger than the outer diameter of the annular member.
(9) The angular ball bearing according to any one of (1) to (4),
A rotating shaft having a stepped portion disposed adjacent to the bearing back side of the angular ball bearing;
Equipped with
A main shaft device characterized in that the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member is larger than the outer diameter of the step portion.
(10) With the rotation axis,
With the housing,
A front bearing and a rear bearing each having the angular ball bearing according to any one of (1) to (4);
Equipped with
The front bearing and the rear bearing are back combined with a constant pressure preload,
The spindle device is characterized in that an air flow path is provided in the housing, which is open to the space between the housing and the rotary shaft on the front side of the bearing of the front side bearing, and which supplies air from the outside. .

According to the angular ball bearing and bearing device of the present invention, in the inner ring, a counter bore is formed on the bearing back side with respect to the inner ring raceway surface, and the minimum outer diameter of the counter bore is the bearing front side with respect to the inner ring raceway surface The seal member, which is smaller than the outer diameter of the shoulder provided on the outer ring and fixed to the bearing rear surface side of the outer ring, has a disc and a straight line toward the axial center of the angular ball bearing as it goes radially inward from the disc And at least one annular ramp that slopes in a shape or curve. The maximum diameter of the inclined portion on the inner surface side in the axial direction of the seal member is smaller than the inner diameter of the end face on the bearing rear surface side of the cage, and the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member is the bearing front surface side of the inner ring Greater than the outer diameter of the shoulder. Thus, for example, when the seal member is attached to the outer ring, even if the position of the seal member varies, interference of the inclined portion with the cage can be prevented. Also, for example, when the angular ball bearings are combined in parallel, or when the annular member such as the inner ring spacer or the step portion of the rotary shaft is disposed adjacent to the bearing back side, the seal member is deformed in the axial direction Even when inclined, the contact between the seal member and a member disposed adjacent to the bearing rear surface side of the angular ball bearing can be prevented, and torque increase and damage to the seal member can be prevented.

Further, according to the spindle device of the present invention, the front bearing and the rear bearing to which the angular contact ball bearing of the present invention is applied are back combined with a constant pressure preload, and the housing is the housing on the bearing front side of the front bearing An air flow passage is formed which opens in the space between the and the rotation shaft and supplies air from the outside. Thereby, even if the seal member on the bearing back side of the front bearing is deformed or inclined in the axial direction by the air from the air flow path, the contact of the seal member is prevented, and the torque increase and the damage of the seal member can be prevented.

It is an important section sectional view of an angular contact ball bearing concerning a 1st embodiment of the present invention. It is a principal part enlarged view of the sealing member of the angular ball bearing shown in FIG. 1, and the outer peripheral surface of an inner ring | wheel. (A) is sectional drawing of the sealing member of the angular ball bearing which concerns on the 1st modification of 1st Embodiment, (b) is the sealing member of the angular ball bearing which concerns on the 2nd modification of 1st Embodiment. It is sectional drawing of (c) is sectional drawing of the sealing member of the angular ball bearing which concerns on the 3rd modification of 1st Embodiment, (d) is concerning the 4th modification of 1st embodiment. It is a sectional view of a seal member of an angular contact ball bearing. FIG. 2 is a cross-sectional view of a bearing device and a main shaft device provided with angularly coupled ball bearings assembled in parallel. It is a sectional view of an angular contact ball bearing concerning a 2nd embodiment of the present invention. It is a sectional view of an angular contact ball bearing concerning a 3rd embodiment of the present invention. It is a sectional view of an angular contact ball bearing concerning a 4th embodiment of the present invention. It is sectional drawing of the angular contact ball bearing which concerns on 5th Embodiment of this invention. It is sectional drawing of the angular contact ball bearing which concerns on 6th Embodiment of this invention. FIG. 10 is a cross-sectional view taken along the line XX in FIG. It is sectional drawing of the angular contact ball bearing which concerns on 7th Embodiment of this invention. It is sectional drawing of the angular contact ball bearing which concerns on 8th Embodiment of this invention. It is sectional drawing of the 1st modification of the bearing apparatus of this invention to which the angular contact ball bearing of 1st Embodiment was applied. It is sectional drawing of the 2nd modification of the bearing apparatus of this invention to which the angular contact ball bearing of 1st Embodiment was applied. It is sectional drawing of the 3rd modification of the bearing apparatus of this invention to which the angular contact ball bearing of 1st Embodiment was applied. It is sectional drawing of the 1st modification of the spindle apparatus of this invention to which the angular contact ball bearing of 1st Embodiment was applied. It is sectional drawing of the 2nd modification of the spindle apparatus of this invention to which the angular contact ball bearing of 1st Embodiment was applied. It is sectional drawing of the main-axis | shaft apparatus with which the conventional angular contact ball bearing was combined in parallel.

Hereinafter, each embodiment of the angular contact ball bearing, bearing device, and spindle device according to the present invention will be described in detail based on the drawings.

First Embodiment
As shown in FIG. 1, in the angular ball bearing 10 of the first embodiment, an outer ring 11 having an outer ring raceway surface 11a on the inner peripheral surface, an inner ring 12 having an inner ring raceway surface 12a on the outer peripheral surface, an outer ring raceway surface 11a and A plurality of balls 13 rollably arranged with a predetermined contact angle θ between the inner ring raceway surfaces 12 a, a cage 14 for holding the plurality of balls 13 in a rollable manner, and axially opposite sides of the outer ring 11 And a pair of

non-contacting seal members

15 and 16 attached to cover the opening between the outer ring 11 and the inner ring 12.

In the outer ring 11, a counter bore 11b having a substantially uniform inner diameter is formed on the bearing front side (the front side of the outer ring 11) with respect to the outer ring raceway surface 11a. Therefore, the inner diameter of the shoulder 11c on the bearing rear surface side (the rear surface of the outer ring 11) with respect to the outer ring raceway surface 11a is smaller than the inner diameter of the shoulder 11d on the bearing front side with respect to the outer ring raceway surface 11a.

On the other hand, the inner race 12 is formed with a tapered counterbore 12b whose diameter is reduced toward the end in the axial direction on the bearing rear surface side (front side of the inner race 12) with respect to the inner raceway surface 12a. For this reason, the minimum outer diameter D1 of the counter bore 12b is smaller than the outer diameter D of the shoulder 12c provided on the bearing front side (the back side of the inner ring 12) with respect to the inner ring raceway surface 12a.

The cage 14 is, for example, an outer ring guiding cage formed of synthetic resin, metal or the like, is guided by the shoulder 11 c on the bearing back side, and the pocket 14 a for holding the ball 13 has a cylindrical shape. It is formed.

As shown in FIGS. 1 and 2, the pair of

seal members

15 and 16 are made of a

core metal

21 and 17 in which a metal plate is formed in an annular shape, and an elastic material such as rubber and elastomer. And

elastic portions

22 and 18 fixed. The

elastic portions

22 and 18 are formed so as to cover the outer peripheral side of the

core metals

21 and 17 and to cover the outer peripheral edge 25 formed so as to slightly project radially outward and the inner peripheral side of the

core metals

21 and 17. And a side wall 27 connecting the outer peripheral edge 25 and the lip 26. Further, in the present embodiment, the seal member 15 on the bearing back side is formed with the inner side wall portion 28 composed of the elastic portion 22 also on the inner side surface of the core metal 21 constituting the inclined portion 24 described later.

The pair of

seal members

15 and 16 is fixed by press-fitting the outer peripheral edge 25 into the mounting grooves 11 e formed at both axial ends of the outer ring 11.

The inner diameter surface of the seal member 15 faces the outer peripheral surface of the counterbore 12b on the bearing rear surface side of the inner ring 12 in a noncontact manner to form a labyrinth seal. Further, the inner diameter surface of the seal member 16 faces the outer peripheral surface of the shoulder 12 c on the bearing front side of the inner ring 12 in a noncontact manner to form a labyrinth seal.

Further, the seal member 15 on the bearing back side extends in the radial direction from the portion fixed to the mounting groove 11e, and the axial center of the angular ball bearing 10 as it goes radially inward from the disk portion 23 (see FIG. And an annular inclined portion 24 linearly inclined at an inclination angle α toward the right in 1). The cored bar 21 is provided across the disk portion 23 and the inclined portion 24 and has a bent portion 29 which is bent radially outside the disk portion 23 and located inside the outer peripheral edge portion 25.

Here, the maximum diameter D3 of the inclined portion 24 (that is, at the boundary point A2 between the disk portion 23 and the inclined portion 24 on the axial outer surface side) on the axial outer surface side (left surface in FIGS. 1 and 2) of the sealing member 15. The diameter D3 of the circle is larger than the outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12 (D3> D). Thereby, even if the seal member 15 is deformed or inclined in the axial direction, for example, the seal member 15 and the members disposed adjacent to the bearing rear surface side (inner ring 12 and inner ring spacer of other angular ball bearings 10 in parallel combination) Interference with the oil seal, the step portion of the rotating shaft, etc. can be prevented, and the torque increase due to the interference and the damage of the seal member 15 can be prevented. In addition, as shown in FIG. 1, in the case where a corner R or a chamfer is provided at the axial end of the shoulder 12c, the maximum diameter D3 of the inclined portion 24 on the outer surface side in the axial direction is The above effect is achieved by making the radius R2 larger than the diameter D2 at the intersection of the chamfered portion and the end face in the axial direction.

In addition, the maximum diameter D4 of the inclined portion 24 (that is, the circle at the boundary point A1 between the disk portion 23 and the inclined portion 24 on the inner surface side in the axial direction) on the inner surface side (right side in FIGS. The diameter D4) of the holder 14 is smaller than the inner diameter D5 of the cage 14, or more strictly, the inner diameter D5 of the bearing back end surface 14b of the cage 14 (D4 <D5). Thereby, even if the seal member 15 is deformed or inclined in the axial direction, the interference between the seal member 15 and the holder 14 is prevented, and the torque increase due to the interference and the damage of the seal member 15 can be prevented.

Further, the maximum diameter D3 of the inclined portion 24 on the outer surface side in the axial direction of the seal member 15 is set smaller than the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction (right side in FIG. 1) of the seal member 15. Thereby, the axial thickness of the inclined portion 24 of the seal member 15 is secured, and the deformation of the seal member 15 is suppressed (D3 <D4).

Further, in the present embodiment, the inclination angle α of the inclined portion 24 is set to be more than 0 ° and 45 ° or less (0 ° <α ≦ 45 °). Thereby, the strength against deformation of the seal member 15 can be secured. The inclination angle α is preferably 30 ° or more and 45 ° or less (30 ° ≦ α ≦ 45 °). Since the circumferential stress (compression force) acting on the inclined portion 24 becomes large when the seal member 15 is deformed to the inner diameter side by setting the inclination angle α to 30 ° or more, the deformation is more difficult.

The inner diameter end face 26 a of the lip portion 26 is formed in a plane substantially parallel to the revolution axis of the ball 13. Further, in accordance with this, the inner diameter end face 21 a of the core metal 21 is also processed into a plane substantially parallel to the revolution axis of the ball 13 after the inclined portion 24 is bent. When the inclination angle α of the inclined portion 24 is more than 45 °, the angle of the tip of the inner diameter portion of the core metal 21 becomes smaller (more acute), and burrs are easily generated when the core metal 21 is formed.

Further, since the inner diameter end face 26a of the lip portion 26 is formed in a plane substantially parallel to the revolution axis X of the ball 13, a long labyrinth seal is formed in the axial direction, and the labyrinth effect is enhanced.

The clearance C between the bearing front side corner of the inner diameter end face 26a of the lip 26 and the outer peripheral surface of the inner ring 12 at which the labyrinth clearance is minimum is the minimum outer diameter D1 of the counterbore 12b of the inner ring 12 with respect to the clearance C. The ratio (C / D1) is set to satisfy 0.0005 or more and 0.03 or less (0.0005 ≦ C / D1 ≦ 0.03). As a result, the sealability can be improved, and a labyrinth seal capable of maintaining good lubricity can be secured.

Furthermore, the ratio (t / D1) of the minimum outer diameter D1 of the counterbore 12b of the inner ring 12 to the thickness t of the core metal 21 is set to 0.0003 or more and 0.3 or less (0.0003 ≦ t /D1≦0.3), both strength against deformation of the seal member 15 and processability can be secured.

Further, as shown in FIG. 1, the bearing back end face 14b of the cage 14 and the bearing front end 26b of the lip 26 overlap by Δ1 as viewed from the radial direction (Δ1 ≧ 0). For this reason, since the grease pushed out from the holder 14 and attached to the inner surface of the seal member 15 is close to the rolling contact portion, the lubricating oil component of the grease can be easily supplied to the rolling contact portion to improve the lubricating performance. can do.

In the sealing member 15, the inner end A4 of the elastic portion 22 is a boundary point between the inclined portion 24 and the inner diameter end face 21a of the core metal 21 from the boundary point A1 between the disk portion 23 and the inclined portion 24 on the inner surface side in the axial direction. It may be any position up to A3. That is, as shown in FIG. 3A, the sealing member 15 may have a configuration without the inner side wall portion 28. Alternatively, assuming that the radial height from the boundary point A1 to the boundary point A3 is L, in the inner side wall portion 28, the radial height from the boundary point A3 is L / 10, as shown in FIG. It may be formed to be L / 2 shown in (c) and 4L / 5 shown in FIG. In the case of FIGS. 3 (a) to 3 (d), the boundary point A1 between the disk portion 23 and the inclined portion 24 on the inner surface side in the axial direction is constituted by the core metal 21.

However, it is preferable that the radial height of the inner side wall portion 28, that is, the position of the inner end A4 be in the range of at least L / 10 to L / 2, as shown in FIG. Is more preferably L / 10. The reason for this is that by providing the inner side wall portion 28, it is possible to prevent the rubber from being peeled off by contact with the boundary point A3 of the edge shape when handling the seal alone, and the inner side wall portion 28 is the inner side surface of the inclined portion 24. Because the length of the rubber is short, it is difficult to cause unevenness in the position of the tip A4 of the elastic portion 22 during vulcanization molding, and it is possible to partially prevent the rubber from peeling by reaching the boundary point A1. There is a point that can be done.

The shape of the seal member 16 on the bearing front side is not particularly limited, but as shown in FIG. 1, it does not have the inclined portion 24 and is formed in a flat disk shape to the inside in the radial direction.

FIG. 4 is a cross-sectional view of a spindle device 40 using a bearing device 30 in which such angular ball bearings 10 are combined in parallel. In the spindle device 40, a pair of angular contact ball bearings 10 combined in parallel is disposed between the rotation shaft 41 and the housing 52. Further, a front outer ring presser 56 for positioning the outer ring 11 of the angular ball bearing 10 is attached to the housing 52. And, in the housing 52 and the front outer ring presser 56, on the bearing front side of the angular ball bearing 10, the space between the housing 52 and the rotary shaft 41 is opened, and the air flow path 55 for air purge which supplies air from the outside. Is formed.

Also in such a bearing device 30, the seal member 15 disposed on the bearing back side of the angular ball bearing 10 includes the inclined portion 24, and the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is The maximum diameter D3 of the inclined portion 24 on the outer surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 at the bearing rear end surface 14b of the cage 14 and is the shoulder 12c of the bearing front side 12c of the inner ring 12 of the angular ball bearing 10. Larger than the outer diameter D. For this reason, even if the seal member 15 is deformed or inclined in the axial direction, the step between the seal member 15 and the inner ring 12 (the shoulder 12c on the bearing front side) of the angular ball bearing 10 disposed on the bearing rear side There is no interference with the part 43. Furthermore, the interference between the seal member 15 and the cage 14 of the angular ball bearing 10 itself is reliably prevented, and the torque increase due to the interference and the damage of the seal member 15 can be suppressed.

Further, even if a part of the air supplied from the air flow path 55 flows into the pair of angular ball bearings 10 combined in parallel, and the seal member 15 provided on the bearing back side is deformed, Interference with the inner ring 12 of the adjacent angular ball bearing 10 and the step 43 of the rotary shaft 41 is prevented by the configuration of the inclined portion 24, and increase in torque and damage to the seal member 15 can be suppressed.

As described above, according to the angular ball bearing 10 of the present embodiment, the counterbore 12b is formed on the bearing rear surface side with respect to the inner ring raceway surface 12a in the inner ring 12 and the minimum outer diameter D1 of the counterbore 12b is , Smaller than the outer diameter D of the shoulder 12c on the bearing front side with respect to the inner ring raceway surface 12a. Further, the seal member 15 fixed to the bearing rear surface side of the outer ring 11 has a disc portion 23 and an annular inclined portion 24 which is inclined toward the axial center of the angular ball bearing 10 as it goes radially inward from the disc portion 23 And. The maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14, and the maximum diameter D3 of the inclined portion 24 on the outer surface side in the axial direction of the seal member 15. Is larger than the outer diameter D of the shoulder 12 c on the bearing front side of the inner ring 12 of the angular ball bearing 10. Therefore, for example, when the seal member 15 is attached to the outer ring 11, even if the position of the seal member 15 varies, the inclined portion 24 is disposed adjacent to the inner ring 12 with the member or the retainer 14 Interference can be prevented. For example, when the angular ball bearings 10 are combined in parallel, even if the seal members 15 are deformed or inclined in the axial direction, the contact between the seal members 15 and the inner ring 12 of the other angular ball bearings 10 disposed adjacent to each other This can prevent the torque increase and the damage of the seal member 15.

Further, since the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is larger than the maximum diameter D3 of the inclined portion 24 on the outer surface side in the axial direction of the seal member 15, the axial direction of the inclined portion 24 of the seal member 15 is The wall thickness of the seal member 15 is secured, and the deformation of the seal member 15 is suppressed.

Further, since the cage 14 and the inclined portion 24 of the seal member 15 overlap when viewed from the radial direction, the grease pushed out from the cage 14 and attached to the inner surface of the seal member 15 is close to the rolling contact portion, and the grease is lubricated. The oil component can be easily supplied to the rolling contact portion, and the lubricating performance is improved.

Second Embodiment
FIG. 5 is a cross-sectional view of the angular ball bearing of the second embodiment. The angular contact ball bearing 10A of the second embodiment differs from the angular contact ball bearing 10 of the first embodiment in the shape of the seal member 15A on the bearing back side. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

In the seal member 15A of the present embodiment, the sloped portion 24 is formed to be bent in two steps, and includes a first sloped portion 24a and a second sloped portion 24b from the outer diameter side. Also in this case, the maximum diameter D3 of the first inclined portion 24a is larger than the outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12 on the axially outer surface side (left side surface in FIG. 5) of the seal member 15A. . Further, the maximum diameter D4 of the first inclined portion 24a is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14 on the inner surface side in the axial direction of the seal member 15A.

Thereby, even if the seal member 15A is deformed or inclined in the axial direction, the inner ring 12 of another angularly assembled ball bearing 10 juxtaposed adjacently disposed on the bearing back side, and a circle such as an inner ring spacer or oil seal Interference with the ring member or the step portion of the rotary shaft and the retainer 14 of the angular ball bearing 10A itself is prevented, and torque increase and damage to the seal member 15A can be prevented.

Third Embodiment
FIG. 6 is a cross-sectional view of the angular ball bearing of the third embodiment. The angular ball bearing 10B of the third embodiment differs from the angular ball bearing 10 of the first embodiment in the shape of the seal member 15B on the bearing back side. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

In the seal member 15B according to the third embodiment, the sloped portion 24c is curved in a curved shape, so that the sloped portion 24c has an annular curved surface that inclines toward the axial center of the angular ball bearing 10B as it goes radially inward from the disk portion 23. It is formed. The maximum diameter D3 of the inclined portion 24c (diameter D3 of the circle at the boundary between the disk portion 23 and the inclined portion 24c on the axial outer surface side) on the axial outer surface side (left surface in FIG. 6) of the sealing member 15B is The diameter is larger than the outer diameter D of the shoulder 12 c on the bearing front side of the inner ring 12. Further, the maximum diameter D4 of the inclined portion 24c (diameter D4 of the circle at the boundary between the disk portion 23 and the inclined portion 24c on the inner surface side in the axial direction) on the inner surface side in the axial direction of the seal member 15B It is smaller than the inner diameter D5 of the end face 14b.

As a result, even if the seal member 15B is deformed or inclined in the axial direction, the inner ring 12 of another angularly assembled ball bearing 10 juxtaposed adjacently disposed on the bearing back side, a circle such as an inner ring spacer, oil seal, etc. Interference with the ring member or the step portion of the rotary shaft and the retainer 14 of the angular ball bearing 10B itself is prevented, and torque increase and damage to the seal member 15B can be prevented. The curved surface of the inclined portion 24c may be formed by a single curved surface, or may be formed by a combination of a plurality of curved surfaces.

Fourth Embodiment
FIG. 7 is a cross-sectional view of the angular ball bearing of the fourth embodiment. The angular ball bearing 10C of the fourth embodiment differs from the angular ball bearing 10 of the first embodiment in the seal member 15C on the bearing back side. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

The seal member 15C of the angular ball bearing 10C according to the fourth embodiment is a so-called shield plate 21A which is formed of only metal without an elastic portion. The shield plate 21A is crimped to a mounting groove 11e formed in a shoulder 11c on the bearing rear surface side of the outer ring 11, and a curled portion 61 fixed to the outer ring 11 and an angular ball bearing 10C from the inner diameter side of the curled portion 61 And the other inclined portion 62 which is inclined outward in the axial direction, the disk portion 23 extending in the radial direction from the inclined portion 62, and the axial center of the angular ball bearing 10C as moving radially inward from the disk portion 23 And an inclined annular portion 24.

The maximum diameter D3 of the inclined portion 24 on the axially outer surface side (left side surface in FIG. 7) of the seal member 15C is larger than the outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12. Further, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15C is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14.

As a result, even if the seal member 15C is deformed or inclined in the axial direction, the inner ring 12 of the other parallel angular ball bearing 10C, which is disposed adjacent to the bearing back side, and a circle such as inner ring spacer or oil seal Interference with the ring member or the step portion of the rotary shaft and the retainer 14 of the angular ball bearing 10 itself is prevented, and torque increase and damage to the seal member 15C can be prevented.

Fifth Embodiment
FIG. 8 is a cross-sectional view of the angular ball bearing of the fifth embodiment. The angular contact ball bearing 10D of the fifth embodiment differs from the angular contact ball bearing 10 of the first embodiment in the shape of the cage 14D. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

The outer ring guiding cage 14D of the angular ball bearing 10D according to the fifth embodiment is formed such that at least the axial length on the bearing back side is short, so that the bearing front surface 14b of the cage 14D and the bearing front of the lip portion 26 The side end portion 26 b is separated in the axial direction, and a gap Δ2 is provided (Δ2> 0).

Thus, since the seal member 15 is separated from the outer ring guide holder 14D, the grease pushed out from the outer ring guide holder 14D is less likely to adhere to the inner surface of the seal member 15, that is, the opening of the labyrinth. , Grease leakage from the labyrinth is suppressed.
In the cage 14D, if there is no problem in strength, the axial length of the annular portion on the bearing front side may be shortened to substantially the same width as the axial length of the annular portion on the bearing back side. By doing this, the bearing space volume can be increased, and an increase in the amount of filled grease can be expected to improve the lubrication life.

Sixth Embodiment
FIG. 9 is a cross-sectional view of an angular ball bearing according to a sixth embodiment, and FIG. 10 is a cross-sectional view taken along the line XX in FIG. The angular contact ball bearing 10E of the sixth embodiment differs from the angular contact ball bearing 10 of the first embodiment in the cage 14E. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

The angular contact ball bearing 10E according to the sixth embodiment includes a ball guide holder 14E guided by a plurality of balls 13 rotatably disposed in the pocket 14a1. As shown in FIG. 10, the convex part 14c which comprises the pocket 14a1 is provided in the internal peripheral surface of the pillar part of the ball | bowl guide holder 14E. Also in this case, similarly to the angular ball bearing 10 of the first embodiment, the bearing back end face 14b of the cage 14E and the bearing front end 26b of the lip 26 overlap by Δ1 when viewed from the radial direction (Δ1 0 0). Therefore, since the grease pushed out from the holder 14E and attached to the inner surface of the seal member 15 is close to the rolling contact portion, the lubricating oil component of the grease can be easily supplied to the rolling contact portion, and the lubricating performance is improved. .

Seventh Embodiment
FIG. 11 is a cross-sectional view of the angular ball bearing of the seventh embodiment. The angular ball bearing 10F of the seventh embodiment differs from the angular ball bearing 10 of the first embodiment in the shapes of the outer ring 11 and the inner ring 12 and the shapes of the

seal members

15 and 16. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

In the outer ring 11 of the angular ball bearing 10F of the seventh embodiment, a tapered counterbore 11b is formed on the bearing front side with respect to the outer ring raceway surface 11a so as to expand in diameter toward the axial end. Further, the inner ring 12 is formed with a counterbore 12b having a substantially uniform outer diameter on the bearing rear side with respect to the inner ring raceway surface 12a, and the minimum outer diameter D1 of the counterbore 12b (ie, the shoulder on the bearing rear side) The outer diameter 12d is smaller than the outer diameter D of the shoulder 12c provided on the front side of the bearing. Therefore, the outer diameter of the seal member 16 is formed larger and the inner diameter of the seal member 15 is formed larger as compared with the angular ball bearing 10 of the first embodiment shown in FIG.
However, also in the present embodiment, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 on the bearing rear surface end surface 14b of the cage 14 Since the maximum diameter D3 of the inclined portion 24 in the above is larger than the outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12 of the angular ball bearing 10F, the same effect as that of the first embodiment can be obtained.

Eighth Embodiment
FIG. 12 is a cross-sectional view of the angular contact ball bearing of the eighth embodiment. The angular contact ball bearing 10 </ b> G of the eighth embodiment differs from the angular contact ball bearing 10 of the first embodiment in the shape of the outer ring 11 and the shape of the seal member 16. The other parts are the same as those of the angular ball bearing 10 of the first embodiment, so the same parts are denoted by the same reference numerals or corresponding reference numerals to simplify or omit the description.

In the angular contact ball bearing 10G of the eighth embodiment, the counter bore 12b is formed only on the inner ring 12. Therefore, in the outer ring 11, the inner diameter of the shoulder 11c on the bearing back side and the shoulder 11d on the bearing front side are the same. For this reason, compared with the angular contact ball bearing 10 of the first embodiment shown in FIG. 1, the outer diameter of the seal member 16 is formed smaller.
However, also in the present embodiment, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 on the bearing rear surface end surface 14b of the cage 14 The maximum diameter D3 of the inclined portion 24 in the above is larger than the outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12 of the angular ball bearing 10G, so that the same effect as that of the first embodiment can be obtained.

(First Modification of Bearing Device)
FIG. 13 is a cross-sectional view of a first modified example of the bearing device in which the pair of angular contact ball bearings according to the first embodiment is back combined via the outer ring spacer 31 and the inner ring spacer 32. In FIG. 13, the outer diameter D6 of the inner ring spacer 32 is larger than the minimum outer diameter D1 of the counterbore 12b and smaller than or equal to the outer diameter D of the shoulder 12c provided on the bearing front side. In the member 15, the maximum diameter D 3 of the inclined portion 24 is larger than the outer diameter D 6 of the inner ring spacer 32 on the axial outer surface side of the seal member 15. Further, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14.

Thereby, even if the seal member 15 is deformed or inclined in the axial direction, the seal member 15 and the inner ring spacer 32 do not interfere with each other. Further, interference between the seal member 15 and the cage 14 of the angular ball bearing 10 itself is also prevented.

As described above, according to the bearing device 30 of the first modification, the angular ball bearing 10 and the inner ring spacer 32 disposed adjacent to the bearing back side of the angular ball bearing 10 are provided. The maximum diameter D3 of the inclined portion 24 on the side is larger than the outer diameter D6 of the inner ring spacer 32, and the maximum diameter D4 of the inclined portion 24 on the inner surface in the axial direction of the seal member 15 is the bearing rear end surface 14b of the cage 14. Smaller than the inner diameter D5 of Therefore, even if the seal member 15 is deformed or inclined in the axial direction, the interference between the seal member 15 and the inner ring spacer 32 and the interference between the angular ball bearing 10 itself and the cage 14 can be prevented, and the torque due to the interference An increase and damage to the seal member 15 can be prevented.

(Second Modification of Bearing Device)
FIG. 14 is a cross-sectional view of a second modified example of the bearing device. In this modification, two sets of angular contact ball bearings according to the first embodiment are provided in parallel, and back-to-back combinations of each set of angular contact ball bearings are applied for fixed position preloading. It is considered as a bearing device.

Also in each angular ball bearing 10 constituting the bearing device 30, the seal member 15 disposed on the bearing back side has the largest diameter D3 of the inclined portion 24 on the axially outer surface side of the seal member 15 disposed on the back side. The outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12 of the angular contact ball bearing 10 (center side in FIG. 14) is larger. In addition, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14.

Thereby, even if the seal members 15 of the angular ball bearings 10 (both left and right ends in FIG. 14) disposed on the axially outer side are deformed or inclined in the axial direction, the angular balls disposed on the seal member 15 and the bearing back side There is no interference with the inner ring 12 of the bearing 10. Further, the interference between the seal member 15 and the cage 14 of the angular ball bearing 10 itself is prevented, and the torque increase due to the interference and the damage of the seal member can be prevented.
In the above description, although the bearing device is described as a four-row combination (DBB), the present invention is not limited to the four-row combination but may be a three-row combination (DBD).

(Third Modification of Bearing Device)
FIG. 15 is a cross-sectional view of a third modification of the bearing device. In this modification, two sets of angular contact ball bearings according to the first embodiment are provided in parallel, and each set of angular contact ball bearings are combined frontally, and a fixed position preload is applied. It is considered as a bearing device.

Also in this case, in each angular ball bearing 10 constituting the bearing device 30, in the seal member 15 disposed on the bearing back side, the maximum diameter D3 of the inclined portion 24 on the axial outer surface side of the seal member 15 is on the back side. The outer diameter D of the shoulder 12c on the bearing front side of the inner ring 12 of the angular ball bearing 10 (both the left and right sides in FIG. 15) disposed is larger. In addition, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14.

Thereby, even if the seal member 15 of the angular ball bearing 10 (axial center in FIG. 15) disposed axially inward is deformed or inclined in the axial direction, the seal member 15 and the angular contact disposed on the bearing back side There is no interference with the inner ring 12 of the ball bearing 10. Further, the interference between the seal member 15 and the cage 14 of the angular ball bearing 10 itself is prevented, and the torque increase due to the interference and the damage of the seal member can be prevented.
In the above description, although the bearing device is described as a four-row combination (DFF), it is not limited to the four-row combination, and may be a three-row combination (DFD).

(First Modification of Spindle Device)
FIG. 16 is a cross-sectional view of a main portion of a first modified example of a main spindle in which a pair of angular contact ball bearings assembled in parallel with each other are back-mounted as a front bearing and a back-side bearing.

The spindle device 40 according to the first modification includes a front bearing 33 disposed between the rotary shaft 41 and the housing 52 to support the front end (right side in FIG. 16) of the rotary shaft 41, and the rear end of the rotary shaft 41. And a rear bearing 34 for supporting the portion (left side in FIG. 16). The front bearing 33 and the rear bearing 34 are configured by a pair of angular ball bearings 10 that are respectively combined in parallel.

The pair of angular ball bearings 10 of the front side bearing 33 is disposed with the bearing back side facing the rear of the rotary shaft 41, and the pair of angular ball bearings 10 of the rear side bearing 34 is the bearing rear side in front of the rotary shaft 41 It is arranged to face. That is, the front side bearing 33 and the rear side bearing 34 are arranged in a back side combination.

The rotary shaft 41 has a large diameter portion 41a at the substantially axial center, the inner ring 12 of the front bearing 33 is fitted to the shaft portion 41b forward of the large diameter portion 41a, and the shaft portion 41c rearward of the large diameter portion 41a. The inner ring 12 of the rear bearing 34 is engaged. Each inner ring 12 of the front bearing 33 and the rear bearing 34 is positioned at an axial position by the stepped portion 43 of the large diameter portion 41 a and the nut 46 screwed to the rotating shaft 41. The outer diameter D7 of the stepped portion 43 is larger than the minimum outer diameter D1 of the counter bore 12b and is set equal to or less than the outer diameter D of the shoulder 12c provided on the front side of the bearing.

The housing 52 has an inward flange 52a at a substantially axial center. The outer ring 11 of the front bearing 33 is fitted in the mounting hole 53a forward of the inward flange 52a, and the outer ring 11 of the rear bearing 34 is engaged in the attachment hole 53b rearward of the inward flange 52a. .

The outer ring 11 of the front bearing 33 is positioned at an axial position by the inward flange 52 a and the front outer ring retainer 56 attached to the housing 52. Further, a plurality of compression springs 60 are disposed at predetermined intervals in the circumferential direction between the outer ring 11 of the rear bearing 34 and the inward flange portion 52a. A rear outer ring presser 57 is disposed behind the outer ring 11 of the rear bearing 34. Thereby, the front side bearing 33 and the rear side bearing 34 are back-mounted, and a constant pressure preload is applied by the elastic force of the compression spring 60.

In the housing 52 and the front outer ring presser 56, an air flow for air purge which is open to the space between the housing 52 and the rotary shaft 41 on the bearing front side of the angular ball bearing 10 of the front bearing 33 A passage 55 is formed.

A part of the air supplied from the air flow passage 55 to the space between the housing 52 and the rotating shaft 41 flows into the angular contact ball bearing 10 of the front bearing 33 from the bearing front side toward the bearing back side. Therefore, the air flowing into the front bearing 33 may cause the seal member 15 mounted on the back of the bearing to be deformed or inclined in the axial direction.

However, the seal member 15 on the bearing back side has a shoulder 12c on the bearing front side of the inner ring 12 of the angular ball bearing 10 in which the maximum diameter D3 of the inclined portion 24 is arranged on the axial outer surface side of the seal member 15. Is larger than the outer diameter D7 of the step portion 43 of the rotating shaft 41. Therefore, even if the seal member 15 is deformed or inclined in the axial direction, the seal member 15 does not interfere with the inner ring 12 of the angular ball bearing 10 disposed on the bearing back side and the step 43 of the rotating shaft 41 . Furthermore, the maximum diameter D4 of the inclined portion 24 on the inner surface side in the axial direction of the seal member 15 is smaller than the inner diameter D5 of the bearing rear end surface 14b of the cage 14, so the seal member 15 is deformed or inclined in the axial direction Even in this case, the interference between the seal member 15 and the cage 14 of the angular ball bearing 10 itself is prevented, and the torque increase due to the interference and the damage of the seal member 15 can be prevented.

As described above, according to the first modification of the spindle device 40, the front bearing 33 and the rear bearing 34, in which the angular ball bearings 10 of the first embodiment are combined in parallel, are back combined with a constant pressure preload, The housing 52 is formed with an air flow path 55 that opens to the space between the housing 52 and the rotating shaft 41 on the bearing front side of the front side bearing 33 and supplies air from the outside. Thereby, even if the seal member 15 is deformed or inclined axially outward by the air flowing into the angular ball bearing 10 of the front bearing 33 from the air flow passage 55, another angular ball disposed adjacent to the seal member 15 Interference of the bearing 10 with the inner ring 12 and interference with the stepped portion 43 of the rotating shaft 41 are prevented. Furthermore, even if the seal member 15 is deformed or inclined inward in the axial direction, interference between the seal member 15 and the cage 14 of the angular ball bearing 10 itself is prevented. Thereby, it is possible to prevent the torque increase due to the interference and the damage of the seal member 15.

(Second Modification of Spindle Device)
FIG. 17 shows a second modification of the spindle device in which the front side bearing 33 formed of a single angular contact ball bearing 10 and the rear side bearing 34 formed of a single angular contact ball bearing 10 are back combined. It is sectional drawing of an example. Also in this case, a constant pressure preload is applied to the front bearing 33 and the rear bearing 34 by the elastic force of the compression spring 60.
The other parts are the same as those of the first modification of the spindle device shown in FIG. 16, and the same effects can be obtained.

The present invention is not limited to the above-described embodiments and modifications, and appropriate modifications, improvements, and the like can be made.
In the above-mentioned embodiment, although a pair of

seal members

15 and 16 are attached to axial direction both sides, the present invention is not limited to this, but a case where seal members 15 are attached only to bearing back side is included in the present invention.

This application is based on Japanese Patent Application No. 2017-168552 filed on Sep. 1, 2017 and Japanese Patent Application No. 2018-008244 filed on Jan. 22, 2018, the contents of which are incorporated herein by reference.

10, 10A, 10B, 10C, 10D, 10E, 10F, 10G angular contact ball bearing 11 outer ring 11a outer ring raceway surface 12 inner ring 12a inner ring raceway surface 12b counter bore 13 ball 14 cage 14b bearing rear side end surface 14D outer ring guide cage (holding vessel)
14E Ball Guide Retainer (Retainer)
15, 15A, 15B, 15C Seal member 23 Disc portion 24 Sloped portion 24a First sloped portion (sloped portion)
24b Second inclined part (inclined part)
30 Bearing device 32 Inner ring spacer (ring member)
33: Front bearing 34: Back bearing 40: Spindle device 41: Rotor shaft 43: Stepped part 52: Housing 55: Air passage D: Outer wheel diameter of the shoulder of the inner ring bearing D1: Outer diameter of the counterbore D3: Outer diameter of the counterbore Maximum diameter D4 of the inclined portion Maximum diameter D5 of the inclined portion on the inner surface in the axial direction of the seal member Inner diameter D6 at the bearing back end of the cage Outer diameter of the inner ring spacer (outside diameter of the annular member
D7 Outer diameter θ contact angle of step

Claims

The outer ring having an outer ring raceway surface on the inner peripheral surface, the inner ring having an inner ring raceway surface on an outer peripheral surface, and a plurality of rollers disposed so as to be rollable with a predetermined contact angle between the outer ring raceway surface and the inner ring raceway surface And a non-contact type seal member provided on at least the back of the bearing to cover an opening between the outer ring and the inner ring. A ball bearing,
In the inner ring, a counter bore is formed on the bearing rear side with respect to the inner ring raceway surface, and the minimum outer diameter of the counter bore is the outer diameter of a shoulder provided on the bearing front side with respect to the inner ring raceway surface Smaller than
The seal member fixed to the bearing rear surface side of the outer ring is at least a disc portion and at least a linear or curved slope toward the axial center of the angular ball bearing as it goes radially inward from the disc portion With one annular ramp,
The maximum diameter of the inclined portion on the inner surface side in the axial direction of the seal member is smaller than the inner diameter of the end face on the bearing back side of the cage,
The angular ball bearing according to claim 1, wherein the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member is larger than the outer diameter of the shoulder portion on the bearing front side of the inner ring.
The angular ball bearing according to claim 1, wherein the maximum diameter of the inclined portion on the inner surface side in the axial direction of the seal member is larger than the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member.
The angular ball bearing according to claim 1 or 2, wherein the retainer and the inclined portion of the seal member overlap in a radial direction.
The angular ball bearing according to claim 1, wherein the cage and the inclined portion of the seal member are axially separated.
A plurality of the angular contact ball bearings according to any one of claims 1 to 4
A bearing device characterized in that the plurality of angular contact ball bearings are combined in parallel.
The bearing device according to claim 5, further comprising the angular ball bearing back-mounted with respect to the plurality of angular ball bearings assembled in parallel.
The bearing device according to claim 5, further comprising the angular ball bearing that is face-mounted to the plurality of angularly-coupled ball bearings that are combined in parallel.
The angular contact ball bearing according to any one of claims 1 to 4;
An annular member disposed adjacent to the bearing back side of the angular ball bearing,
Equipped with
The maximum diameter of the inclined portion on the axial outer surface side of the seal member is larger than the outer diameter of the annular member.
The angular contact ball bearing according to any one of claims 1 to 4;
A rotating shaft having a stepped portion disposed adjacent to the bearing back side of the angular ball bearing;
Equipped with
A main shaft device characterized in that the maximum diameter of the inclined portion on the outer surface side in the axial direction of the seal member is larger than the outer diameter of the step portion.
With the rotation axis,
With the housing,
A front bearing and a rear bearing each having the angular ball bearing according to any one of claims 1 to 4;
Equipped with
The front bearing and the rear bearing are back combined with a constant pressure preload,
The spindle device is characterized in that an air flow path is provided in the housing, which is open to the space between the housing and the rotary shaft on the front side of the bearing of the front side bearing, and which supplies air from the outside. .