JP2016002622A - Main spindle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a main spindle device capable of discharging lubricating oil from an oil discharge hole, and capable of preventing abnormal heating by oil quantity excess of a lubricant inside of a bearing, regardless of a turning attitude.SOLUTION: In a main spindle device 10, a plurality of notches 80 penetrating in the radial direction are formed in a front side bearing outer ring presser 29, and the circumferential directional whole peripheral groove 81 extending over the whole periphery in the circumferential direction, is formed on an inner peripheral surface of a front side housing 21 opposed to an outer peripheral surface of the front side bearing outer ring presser 29, and the inner peripheral surface of the front side housing 21 is formed with a circumferential directional recessed groove 82 for respectively communicating at least one oil discharge hole 70 formed in the front side housing 21 and the circumferential directional whole peripheral groove 81. The circumferential directional recessed groove 82 is constituted of a circular arc surface 82a of uniform curvature extending to both sides in the circumferential direction from the oil discharge hole 70 and a rising surface 82b continuing with the circumferential directional whole peripheral groove 81 from both ends of the circular arc surface 82a.

Description

  The present invention relates to a spindle device that can be applied to a multi-axis control machine tool or the like and is supplied with lubricating oil from the outside and can rotate at high speed.

  As a conventional spindle device, as a method of lubricating a bearing arranged inside, an oil-air lubrication method or an oil mist lubrication method that uses air to supply a small amount of lubricating oil from the outside to the inside of the bearing, A direct injection method is employed in which direct injection is intermittently performed at a high speed into the bearing. As shown in FIG. 10, in the main shaft device 100 of the oil / air lubrication method described in Patent Document 1, an angular ball bearing 103 that rotatably supports a rotating shaft 102 with respect to a housing 101, and a spacer 105 through an oil supply passage 104. Oil air is fed from the provided through hole 106, and the oil air is discharged to the outside through the notch 107 formed in the spacer 105 and the oil drain passage 108 formed in the housing 101 below the angular ball bearing 103.

JP 2002-361540 A

  Incidentally, a spindle device applied to a multi-axis control machine tool such as a multi-task machine or a 5-axis machine is used while changing its posture such as turning along with machining. However, in the spindle device of the lubricating oil supply system as described in Patent Document 1, the oil drain passage is provided only at one place in the circumferential direction and the oil is naturally drained from below, so that the posture of the spindle device is changed. When it is used, there is a possibility that the lubricant is not discharged from the oil drainage passage and stays in the bearing, or the lubricant that has once reached the oil drainage passage returns to the inside of the bearing due to a change in posture. Since the lubricant is continuously supplied, if it accumulates inside without being discharged to the outside, there is a risk of abnormal heat generation due to excessive oil amount or stirring resistance.

  The present invention has been made in view of the above-described circumstances, and the purpose thereof is to allow the lubricating oil to be discharged from the oil discharge hole regardless of the turning posture, and an abnormality due to excessive oil amount inside the bearing or stirring resistance. An object of the present invention is to provide a spindle device capable of preventing heat generation.

The above object of the present invention can be achieved by the following constitution.
(1) A main shaft device in which a rotating shaft is rotatably supported by a housing via a bearing, and the bearing is lubricated by lubricating oil supplied from the outside,
The outer ring of the bearing is internally fitted in the housing and is positioned in the axial direction with respect to the housing using an outer ring positioning member comprising an outer ring spacer or an outer ring presser opposed in the axial direction.
In either one of the outer ring and the outer ring positioning member facing each other, a plurality of first radial oil passages penetrating in the radial direction are formed,
The outer ring or the outer ring positioning member on which the first radial oil passage is formed, and the inner peripheral surface of the housing that faces the outer peripheral surface have the plurality of first diameters. A circumferential circumferential groove is formed which communicates with the directional oil passage and extends over the circumferential circumference;
A second radial oil passage is formed on the inner peripheral surface of the housing to communicate with at least one oil drain hole formed in the housing and the circumferential circumferential groove, respectively.
The first radial oil passage is at least six notches formed at substantially equal intervals in the circumferential direction on either one of the opposing surfaces of the outer ring and the outer ring positioning member,
The second radial oil passage is constituted by an arc surface having a uniform curvature extending from the oil draining hole to both sides in the circumferential direction, and a rising surface continuing from both ends of the arc surface to the circumferential circumferential groove. Spindle device characterized in that it is a circumferential groove.
(2) The spindle device according to (1), wherein the lubricating oil is drained by suction with a negative pressure.

  According to the spindle device of the present invention, a plurality of first radial oil passages penetrating in the radial direction are formed in either one of the outer ring and the outer ring positioning member (outer ring spacer or outer ring presser) facing each other, The outer ring or the outer ring positioning member on which the first radial oil passage is formed and the inner peripheral surface of the housing facing the outer peripheral surface communicate with the plurality of first radial oil passages. A circumferential circumferential groove extending over the entire circumferential direction, and at least one oil drain hole formed in the housing on the inner circumferential surface of the housing; and a circumferential circumferential groove; Are formed in the second radial oil passage. Accordingly, the lubricating oil that has lubricated the bearing can be discharged from the oil drain hole regardless of the turning posture, and abnormal heat generation due to excessive lubricating oil or stirring resistance in the bearing can be prevented.

  Further, when communicating with the first radial oil passage and the second radial oil passage by the circumferential circumferential groove, the outer ring or the outer ring positioning member and the housing are assembled without considering the circumferential phase. be able to.

Further, the first radial oil passage is at least six notches formed at substantially equal intervals in the circumferential direction on either one of the opposed surfaces of the outer ring and the outer ring positioning member facing each other. The radial oil passage is a circumferential direction constituted by an arc surface having a uniform curvature extending from the oil drain hole to both sides in the circumferential direction and a rising surface continuous from both ends of the arc surface to the circumferential circumferential groove. It is a groove. As a result, the lubricating oil inside the bearing can be recovered by any notch depending on the turning posture, and the lubricating oil discharged from the circumferential circumferential groove can be efficiently collected by the circumferential concave groove. It can be recovered well.
In particular, by forming the circumferential groove with an arc surface and a rising surface, the phase angle range of the circumferential groove can be increased, and the groove depth of the groove can be easily adjusted, Lubricating oil can easily flow into the grooves for various turning angles, and the oil drainage is further improved.

  Further, since the lubricating oil is discharged by suctioning with a negative pressure, the recovered oil can be more reliably collected.

1 is a side view of a machine tool to which a spindle device according to a first embodiment of the present invention is applied. It is sectional drawing of the main axis | shaft apparatus of FIG. (A) is sectional drawing in alignment with AA of FIG. 2 which shows the discharge path | route of a main axis | shaft apparatus, (b) is B expanded sectional drawing of FIG. (A) is a figure which shows the state which turned the main-spindle apparatus around the 1st axis line, (b) is a figure which shows the state which turned the main-axis apparatus around the 2nd axis line. It is sectional drawing which shows the discharge path | route as a comparative example. It is a figure which shows each waste oil reservoir position about a comparative example and an Example when a main shaft apparatus is rotated in the A direction and the B direction, and is changed in posture. (A) is an enlarged sectional view of the spindle device in the posture of α = 45 degrees and β = −90 degrees, (b) is a diagram showing the oil sump position in the posture of (a), (c ) Is an enlarged cross-sectional view of the spindle device in the posture of α = 45 degrees and β = −60 degrees, (d) is a diagram showing the oil sump position in the posture of (c), and (e). , Α = 45 degrees, β = −30 degrees, and is an enlarged cross-sectional view of the spindle device, (f) is a diagram showing a drainage reservoir position in the attitude (e), (g) is α FIG. 7 is an enlarged cross-sectional view of the spindle device in the postures of = 45 degrees and β = 0 degrees, and (h) is a view showing the oil sump position in the posture of (g). It is sectional drawing which shows the discharge path which concerns on the modification of 1st Embodiment. (A) is sectional drawing in alignment with IX-IX of (b) which shows the discharge | emission path | route of the main axis | shaft apparatus which concerns on 2nd Embodiment of this invention, (b) respond | corresponds to the B section of FIG. It is an expanded sectional view. It is sectional drawing which shows the example of the conventional main axis | shaft apparatus.

  Hereinafter, a spindle device according to each embodiment of the present invention will be described in detail with reference to the drawings.

(First embodiment)
As shown in FIG. 1, in the machine tool 1, a spindle head 4 is rotatably supported between a pair of support plates 3 erected on a table base 2, and the spindle head 4 is first driven by a drive mechanism (not shown). Rotates around the pivot axis O1. Further, a bracket 11 of the spindle device 10 is rotatably supported between a pair of support arms 5 provided on the spindle head 4, and the spindle device 10 is rotated around the second pivot axis O2 by a drive device (not shown). Rotate. Accordingly, the main spindle device 10 turns around the first turning axis O1 orthogonal to the axis X of the rotating shaft 12 to be described later, and the second axis orthogonal to the axis X of the rotating shaft 12 and the first turning axis O1. By turning around the turning axis O2, the posture can be changed.

  As shown in FIG. 2, the spindle device 10 is a motor built-in system, and a hollow rotary shaft 12 is provided at the center in the axial direction, and a draw bar 13 slides on the axis of the rotary shaft 12. It is freely inserted. The draw bar 13 urges the pull stud 15 attached to the tool holder 14 in the counter tool side direction (right direction in the figure) by the force of the disc spring 17 via the clamp ball 16. It fits with the taper surface 18 of the rotating shaft 12. A tool T (see FIG. 4) is attached to the tool holder 14. As a result, the rotary shaft 12 clamps the tool T at one end (the left side in the figure) so that the tool T can be attached.

  The rotary shaft 12 is mounted on the bracket 11 (see FIG. 1) by two rows of front bearings 50 and 55 that support the tool side and two rows of rear bearings 60 and 65 that support the opposite tool side. The outer cylinder 19 constituting the fixed housing H is rotatably supported.

  The rotor 20 is fitted on the outer peripheral surface of the rotating shaft 12 between the front bearings 50 and 55 and the rear bearings 60 and 65 by shrink fitting. The stator 22 disposed around the rotor 20 is fixed to the outer cylinder 19 by fitting a cooling jacket 23 shrink-fitted into the stator 22 into the outer cylinder 19. Therefore, the rotor 20 and the stator 22 constitute a motor, and by supplying electric power to the stator 22, a rotational force is generated in the rotor 20 and the rotating shaft 12 is rotated.

  Further, the rear housing 24 and the rear lid 26 constituting the housing H are fixed to the opposite side of the outer cylinder 19 on the tool side. The rear lid 26 is provided with an unclamping mechanism (not shown). When exchanging the tool, the draw bar 13 is advanced to the tool side (left side in the figure), and the tool T is unclamped.

  The front bearings 50 and 55 are angular contact ball bearings each having outer rings 51 and 56, inner rings 52 and 57, balls 53 and 58 as rolling elements arranged with contact angles, and a cage (not shown). Yes (see FIG. 3B), the rear bearings 60 and 65 are angular balls having outer rings 61 and 66, inner rings 62 and 67, balls 63 and 68 as rolling elements, and a retainer (not shown). It is a bearing. The front bearings 50 and 55 (parallel combination) and the rear bearings 60 and 65 (parallel combination) have a structure in which constant pressure is preloaded by the coil springs 90 that are substantially equally distributed in the circumferential direction, and are combined with each other on the back side. It is arranged to become.

The outer rings 51 and 56 of the front bearings 50 and 55 are fitted into a front housing 21 constituting a housing H fixed to the outer cylinder 19 on the tool side, and are clamped to the front housing 21 by bolts. 29 is positioned and fixed in the axial direction with respect to the front housing 21 via the outer ring spacer 30. The inner rings 52 and 57 of the front bearings 50 and 55 are externally fitted to the rotary shaft 12 and are axially connected to the rotary shaft 12 via the inner ring spacer 32 by a nut 31 fastened to the rotary shaft 12. Positioning is fixed.

The outer rings 61 and 66 of the rear bearings 60 and 65 are fitted inside a sleeve 25 that is slidable in the axial direction with respect to the rear housing 24 inside the rear housing 24. It is positioned and fixed in the axial direction with respect to the sleeve 25 via the outer ring spacer 34 by the rear bearing outer ring presser 33 fastened with bolts. The inner rings 62 and 67 of the rear bearings 60 and 65 are fitted on the rotary shaft 12, and the inner ring spacer 36 and the detected portion 38 of the speed sensor 37 are moved by another nut 35 fastened to the rotary shaft 12. The positioning is fixed through. The front bearing outer ring retainer 29, the outer ring spacer 30, the rear bearing outer ring retainer 33, and the outer ring spacer 34 constitute the outer ring positioning member of the present invention.

  A detection unit 39 of the speed sensor 37 is fixed to a position opposite to the detected unit 38 in the radial direction on the side opposite to the tool side of the rear bearing outer ring presser 33 and detects the rotation speed of the rotary shaft 12. Further, a front cover 40 is bolted to the tool side end surface of the front bearing outer ring presser 29.

  Here, as shown in FIG. 2, the front bearings 50 and 55 and the rear bearings 60 and 65 are lubricated to the front housing 21, the outer cylinder 19, the rear housing 24, and the rear lid 26 that constitute the housing H, respectively. A plurality of oil supply passages 41 and 42 are formed, and a lubrication device 43 that feeds the lubricant oil is attached to one end side of each of the passages 41 and 42 via a pipe, a pipe joint, and the like (not shown). The lubrication system supplied by the lubrication device may be oil lubrication, and may be any of oil-air lubrication, oil mist lubrication, direct injection lubrication, and the like. In FIG. 2, the oil supply passages 41 and 42 for lubricating the front bearing 50 and the rear bearing 60 are shown in the same cross section, but they are actually arranged in different circumferential phases. An oil supply passage for lubricating the front bearing 55 and the rear bearing 65 arranged in a circumferential phase different from the passages 41 and 42 is not shown.

  In the front housing 21 and the rear housing 24, nozzles 44 and 45 communicating with the other end sides of the oil supply passages 41 and 42 are attached so as to pass through the outer ring spacers 30 and 34 toward the inside of the bearing. The nozzles 44 and 45 supply the lubricating oil sent by the lubricating device 43 into the bearing space from the sides of the bearings 50, 55, 60 and 65.

  The housing H is formed with a plurality of oil drain holes 70 and 71 for discharging the lubricating oils that lubricate the front bearings 50 and 55 and the rear bearings 60 and 65, respectively. A negative pressure generating device 72 for sucking lubricating oil is connected to one end side (opening side to the outside of the spindle device) via a pipe, a pipe joint, etc., not shown. In FIG. 2, the oil drain holes 70 and 71 are shown in the same cross section, but are actually formed in different circumferential phases.

  As shown in FIGS. 3A and 3B, the oil drain hole 70 has a turning direction around the first turning axis O1 of the spindle device 10 (hereinafter also referred to as A direction) and around the second turning axis O2. Are formed at four locations in the circumferential direction along the turning direction (hereinafter also referred to as the B direction).

  A plurality of (eight in this embodiment) notches 80 penetrating in the radial direction are formed on the surface facing the outer ring 51 of the front bearing 50 fitted to the inner peripheral surface of the front housing 21 of the front bearing outer ring retainer 29. A (first radial oil passage) is formed. The notches 80 are formed at four locations in the circumferential direction along the A direction and the B direction, and one portion is formed at approximately equal intervals between the four locations, for a total of 45 degrees at 45 degrees. Formed at intervals. The reason why the notches 80 are formed at equal intervals is that the outer ring 51 facing the front bearing outer ring presser 29 can be pressed evenly, and distortion of the outer ring 51 due to variations in pressing force is prevented.

  In addition, the inner peripheral surface of the front housing 21 facing the outer peripheral surface of the front bearing outer ring retainer 29 in which the notches 80 are formed communicates with the plurality of notches 80 and extends over the entire circumference in the circumferential direction. A circumferential circumferential groove 81 is formed.

Furthermore, a plurality of oil drain holes 70 formed in the front housing 21 and a circumferential circumferential groove 81 are respectively formed on the inner circumferential surface of the front housing 21 at the same axial position as the circumferential circumferential groove 81. The same number of circumferential concave grooves 82 (second radial oil passages) as the number of oil drain holes 70 that communicate with each other are formed. Circumferential grooves 82 are also formed at four locations in the circumferential direction along the A direction and the B direction, and have a uniform curvature (curvature radius R1) extending from the oil drain hole 70 to both sides in the circumferential direction. 82a and a rising surface 82b continuous from the both ends of the arc surface 82a to the circumferential groove 81 in the circumferential direction.
In the present embodiment, the rising surface 82b is formed by another arc surface having a uniform curvature (curvature radius R2) larger than the curvature of the arc surface 82a.

  Hereinafter, as shown in FIGS. 4 (a) and 4 (b), FIG. 6 shows the oil sump position when the posture is changed by turning the spindle device 10 in the A direction and the B direction. In FIG. 6, black portions indicate drainage, and arrows indicate the direction of gravity of the spindle device 10. Further, FIG. 5 shows a comparative example for confirming the oil sump position by forming a pair of notches 80 in a circumferential phase along the B direction, and a pair of circumferential grooves 82 and a pair of drainage. The oil hole 70 is formed in the same circumferential phase as the notch 80 of the front housing 21.

In the structure of the comparative example shown in FIG. 5, when turning in the B direction at ± 90 degrees from the vertical posture (turning angle α = 90 degrees, β = 0 degrees), as shown in the upper part of FIG. No oil accumulation occurs. That is, since the oil drainage path (including the notch 80, the circumferential groove 82, and the oil drainage hole 70) is always positioned downward (in the direction of gravity) in accordance with the turning of the main spindle device 10, the oil drainage is performed in the B direction. In any swirl phase, it does not stay in the vicinity of the bearing 50 and is guided to the oil drain hole 70. Only in the vertical position, drainage oil temporarily accumulates in the vicinity of the bearing side surface (entire circumferential part), but when either swivel in direction B, the drainage path phase becomes lower, so drainage oil It is discharged into the hole 70 and does not cause a problem. However, the spindle device 10 is in the B direction when the spindle posture seen in the multi-tasking machine or the 5-axis machining machine is inclined in the A direction (α ≠ 0 degree, or α ≠ 90 degrees, in FIG. 6, α = 45 degrees). 5, in the structure of the comparative example of FIG. 5, as shown in the middle stage of FIG. 6, the accumulated position of the drained oil moves along the circumferential direction, and the drained oil path is shifted from below (the direction of gravity). Waste oil collects near the bearing side. If the spindle device 10 continues to be operated in this state, oil stagnation increases, unnecessary drained oil returns to the inside of the bearing, and abnormal heat generation may occur due to oil agitation resistance, leading to damage such as seizure. .

  On the other hand, in the case of the oil drainage route of the present embodiment, as shown in the lower part of FIG. 6 and FIG. 7, when turning in the B direction at the turning angle α = 45 degrees, the turning angle β is in the range of ± 90 degrees. In any case, the drained oil flows into the circumferential circumferential groove 81 from the notch 80 in any posture. Thereafter, even if the attitude of the spindle device 10 changes, the oil only moves in the circumferential direction in the circumferential groove 81 in the direction of gravity, and the drained oil does not flow backward from the notch 80 into the bearing, and finally the drained oil. It is discharged from the hole 70 to the outside. Therefore, regardless of the change in the attitude of the spindle device 10, abnormal heat generation due to an excessive amount of oil in the bearing does not occur.

Further, when the lubricating oil is discharged from the oil drain holes 70 and 71 to the outside of the spindle device 10, the negative pressure is sucked by using the negative pressure generator 72, so that the drain oil can be recovered from the rear portion of the spindle device. It becomes. When the oil drain holes 70 and 71 are opened at the front part of the spindle device and allowed to fall naturally, cutting oil, dust and foreign matter may enter the inside, so the oil drain holes 70 and 71 are opened at the rear part of the spindle device. It is preferable to do.
In the present embodiment, the negative pressure generator 72 sucks the drained oil under negative pressure, but it may be structured to recover by natural fall.

  Further, as shown in FIGS. 3A and 3B, a plurality of notches 80 are also formed on opposing surfaces on both sides in the axial direction of the outer ring spacer 30 that face the outer rings 51 and 56 of the front bearings 50 and 55. A circumferential circumferential groove 81 and a plurality of circumferential grooves 82 are formed on the inner circumferential surface of the front housing 21 that is formed in the same position as the outer ring spacer 30 in the axial direction. Communicated with. Thereby, even when it has a plurality of front bearings 50 and 55 as in the present embodiment, the lubricating oil that has lubricated the front bearings 50 and 55 can be discharged smoothly, and the spindle device 10 is in the A direction. Alternatively, the lubricating oil can be smoothly discharged even when tilted in the direction B by -90 degrees to -180 degrees or 90 degrees to 180 degrees.

  In particular, the circumferential concave groove 82 includes a circular arc surface 82a having a uniform curvature extending from the oil drain hole 70 to both sides in the circumferential direction, and a rising surface 82b continuous from the both ends of the circular arc surface 82a to the circumferential circumferential groove 81. , The phase angle range of the circumferential groove 82 can be increased, the groove depth of the groove 82 can be easily adjusted, and the groove groove 82 can be adjusted for various turning angles. The inflow of lubricating oil is facilitated, and the oil drainage is further improved.

  Furthermore, in the above embodiment, the front bearing outer ring retainer 29, the outer ring spacer 30, and the front bearings 50 and 55 for positioning the first radial oil path, the circumferential circumferential groove, and the second radial oil path with the front bearings 50 and 55, However, the present invention may be applied to the rear bearing outer ring presser 33 for positioning the rear bearings 60 and 65, the outer ring spacer 34, and the sleeve 25 in which the oil drain hole is formed. .

  Further, as the number of the notches 80 increases, it becomes easier to introduce oil drainage from the bearing side surface to the circumferential circumferential groove, but it is sufficient that at least six are formed at substantially equal intervals in the circumferential direction. Preferably, the cutouts 80 may be formed at approximately eight intervals in the circumferential direction as in the present embodiment, and more preferably, 12 notches are formed at approximately equal intervals in the circumferential direction as shown in FIG. What is necessary is just to form a location.

(Second Embodiment)
FIG. 9 shows an enlarged discharge path of the spindle device according to the second embodiment of the present invention. In this embodiment, a plurality of (eight in the present embodiment) notches 80 (first radial oil) penetrate in the radial direction on the surface of the outer ring 51 of the front bearing 50 facing the front bearing outer ring presser 29. Road) is formed. As in the first embodiment, the notches 80 are also formed at four locations in the circumferential direction along the A direction and the B direction, and one portion is formed at approximately equal intervals between the four locations. , A total of 8 places are formed at intervals of 45 degrees.

  A circumferential circumferential groove 81 communicating with the plurality of notches 80 is formed on the outer circumferential surface of the outer ring 51 at the same position in the axial direction where the notches 80 are formed over the entire circumference in the circumferential direction. Yes.

  Furthermore, a plurality of oil drain holes 70 formed in the front housing 21 and a circumferential circumferential groove 81 are respectively formed on the inner circumferential surface of the front housing 21 at the same axial position as the circumferential circumferential groove 81. The same number of circumferential concave grooves 82 (second radial oil passages) as the number of oil drain holes 70 that communicate with each other are formed. The circumferential grooves 82 are also formed at four locations in the circumferential direction along the A direction and the B direction, and have a uniform curvature arc surface 82a extending from the oil drain hole 70 to both sides in the circumferential direction, and an arc surface The rising surface 82b continues from the both ends of 82a to the circumferential groove 81 in the circumferential direction.

  Accordingly, in the discharge path configured as described above, the lubricating oil can be discharged from the notch 80 positioned in the gravitational direction to the circumferential circumferential groove 81 according to the turning posture, as in the first embodiment. The lubricating oil discharged into the circumferential circumferential groove 81 can only move in the direction of gravity in the circumferential circumferential groove even if the posture changes, and from the first radial oil passage to the inside of the bearing. The lubricating oil can be reliably discharged from the oil drain hole 70 without backflowing into the oil.

  Further, as shown in FIG. 9, a plurality of notches 80 formed on opposing surfaces on both sides in the axial direction of the outer ring spacer 30 facing the outer rings 51, 56 of the front bearings 50, 55, A circumferential circumferential groove 81 that communicates with a plurality of circumferential grooves 82 formed on the circumferential surface may also be formed on the outer circumferential surface of the outer ring spacer 30 in the same axial position as the notch 80.

In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
In the embodiment described above, the front bearing and the rear bearing are configured by a pair of angular ball bearings, but the type and number of the bearings are not limited to this, and can be appropriately designed according to the state of use. Furthermore, the lubrication system of the front bearing and the rear bearing can be arbitrarily set.

  Further, the plurality of first radial oil passages of the present invention are not limited to the plurality of notches 80 of the above-described embodiment, and any one of the outer ring and the outer ring positioning member facing each other penetrates in the radial direction. For example, it may be formed by a through hole.

  Further, as in the above-described embodiment, the circumferential circumferential groove of the present invention has an outer circumferential surface of the outer ring or outer ring positioning member in which the first radial oil passage is formed, and an inner surface of the housing facing the outer circumferential surface. What is necessary is just to form in either one of a surrounding surface.

  Further, in the present embodiment, the rising surface constituting the circumferential groove of the present invention is another arc surface having a uniform curvature, but the present invention is not limited to this, and the entire circumferential direction from both ends of the arc surface 82a. What is necessary is just to be continuous with the circumferential groove 81.

DESCRIPTION OF SYMBOLS 1 Machine tool 10 Main shaft apparatus 12 Rotating shaft 19 Outer cylinder 20 Rotor 21 Front housing 22 Stator 29 Front bearing outer ring retainer (outer ring positioning member)
30 Outer ring spacer (outer ring positioning member)
50, 55 Front bearing 24 Rear housing 60, 65 Rear bearing 80 Notch (first radial oil passage)
81 Circumferential circumferential groove 82 Circumferential concave groove (second radial oil passage)
H housing

Claims (2)

A rotary shaft is rotatably supported by a housing via a bearing, and the spindle device is lubricated by lubricating oil supplied from the outside,
The outer ring of the bearing is internally fitted in the housing and is positioned in the axial direction with respect to the housing using an outer ring positioning member comprising an outer ring spacer or an outer ring presser opposed in the axial direction.
In either one of the outer ring and the outer ring positioning member facing each other, a plurality of first radial oil passages penetrating in the radial direction are formed,
The outer ring or the outer ring positioning member on which the first radial oil passage is formed, and the inner peripheral surface of the housing that faces the outer peripheral surface have the plurality of first diameters. A circumferential circumferential groove is formed which communicates with the directional oil passage and extends over the circumferential circumference;
A second radial oil passage is formed on the inner peripheral surface of the housing to communicate with at least one oil drain hole formed in the housing and the circumferential circumferential groove, respectively.
The first radial oil passage is at least six notches formed at substantially equal intervals in the circumferential direction on either one of the opposing surfaces of the outer ring and the outer ring positioning member,
The second radial oil passage is constituted by an arc surface having a uniform curvature extending from the oil draining hole to both sides in the circumferential direction and a rising surface continuing from the both ends of the arc surface to the circumferential circumferential groove. Spindle device characterized in that it is a circumferential groove.   The spindle device according to claim 1, wherein the lubricating oil is discharged by sucking under a negative pressure.

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