JP5110083B2 - Spindle device - Google Patents

Description

  The present invention relates to a spindle device, and more particularly to a spindle device including a rotary joint that supplies fluid such as cutting fluid and compressed air to a plurality of fluid supply paths formed on a rotating shaft.

  2. Description of the Related Art Conventionally, in a spindle device that supports a tool spindle of a machine tool body, an under-lace lubrication system that supplies fluid from the spindle to a bearing inner ring with high-speed rotation of the tool spindle is known (see, for example, Patent Document 1). ). In the spindle device 200 described in Patent Document 1, as shown in FIG. 10, the rotation shaft 101 is rotatably supported with respect to the housing 202 by a plurality of bearings 203 (203A, 203B, 203C, 203D). The rotary shaft 201 is provided with a tapered hole 201a for attaching the tool holder 204 to the front end portion thereof, and further, an axial hole 201b communicating with the tapered hole 201a is formed in the shaft core. A draw bar 205 for attaching / detaching the tool holder 204 is accommodated in the axial hole 201b.

  In the draw bar 205, an air supply hole 206 having one end opening in the tapered hole 201 a is formed in the axial direction of the draw bar 205. The rotating shaft 201 is formed with a lubricating oil supply hole 207 having one end opened toward the bearing 203 (203A, 203B, 203C, 203D) in the axial direction and the radial direction. Then, compressed air and lubricating oil are supplied from the end of the rotating shaft 201 on the side opposite to the tapered hole, and compressed air and lubrication are supplied to the tapered hole 201a and the bearing 203 through the air supply hole 206 and the lubricating oil supply hole 207, respectively. Supply oil.

  Further, as another spindle device, it has been proposed to supply a fluid from within the main shaft in order to confirm the close contact between the taper hole of the tool main shaft and the taper portion of the tool holder (see, for example, Patent Document 2). In the spindle device 300 described in Patent Document 2, as shown in FIG. 11, the flow paths 302 and 303 are formed on the rotating shaft 301, and the flow path 305 is formed in the axial direction through the axis of the draw bar 304. A pipe 306 is inserted to form a double-structure flow path, cooling coolant is supplied to a tool (not shown) via the flow paths 302 and 305, and the taper hole 301a is not shown via the flow path 303 and the pipe 306. Air for confirming contact with the tool holder is supplied.

  Further, as shown in an enlarged view in FIG. 12, a rotary joint 311 connected to the rear end portion of the rotating shaft 301 is provided. The rotary joint 311 includes a housing 313 having a coolant supply port 314 and an adhesion confirmation air supply port 315, and a rotating unit 317 that is rotatably supported in the housing 313 by a rolling bearing 316.

A coolant passage 318 that communicates with the coolant supply port 314 and an air passage 319 that communicates with the adhesion confirmation air supply port 315 are formed in the rotating portion 317 in the axial direction. A front end portion of the rotating portion 317 is fixed to a rear end portion of the rotating shaft 312 by a bolt 320. As a result, the coolant passage 318 and the air passage 319 of the rotating portion 317 communicate with the axial holes 321 and 322 provided in the rotating shaft 312, respectively, and the coolant supplied from the coolant supply port 314 is supplied to the axial hole 321. The contact confirmation air supplied from the contact confirmation air supply port 315 is supplied to the taper hole of the rotating shaft 301 through the axial hole 322.
JP-A-6-206103 Japanese Patent Laid-Open No. 10-225845

  By the way, in both the spindle devices 200 and 300 described in Patent Document 1 and Patent Document 2, a small diameter and long through-hole is formed in the rotating shafts 201 and 301 and the draw bars 205 and 304 in the axial direction, so that coolant or compressed air is formed. Therefore, the processing of the flow path is difficult, and there is a problem that much time and cost are required for production. Further, in the spindle device 300 described in Patent Document 2, the pipe 306 is inserted into the flow path 305 formed in the axial direction of the draw bar 304 to form a double-structured supply flow path. In addition to this difficulty, there is a problem that the structure becomes complicated.

  In addition, the rotating part 317 of the rotary joint 311 is an integral part formed by lathe processing or the like, and is fixed to the rotating shaft 301 with a bolt 320. Therefore, the coolant passage 318 provided in the rotating part 317 and the air The passage 319 and the axial holes 321 and 322 formed in the rotating shaft 301 are communicated with each other, in other words, the rotating shaft 301 and the rotating portion 317 must be fixed in phase and fixed. There was a problem that required man-hours. Further, since the rotating part 317 is formed as an integral part, for example, even if there is a problem only in the front end part of the rotating part 317 such as the joint part with the rotating shaft 301 or the vicinity of the outlets of the passages 318 and 319, the rotary joint It is necessary to disassemble 311 and replace the entire rotating unit 317, and there is room for improvement in terms of maintenance.

  The present invention has been made in view of the above-described problems, and its purpose is to supply a plurality of fluids such as cutting fluid and compressed air to a plurality of fluid supply paths provided on a rotating shaft, An object of the present invention is to provide a spindle apparatus having a rotary joint that is excellent in maintainability and can be easily assembled. Another object of the present invention is to provide a spindle device in which a flow path through which a fluid passes through a rotating shaft can be easily processed at low cost, and a built-in motor rotor can be easily assembled.

The above object of the present invention can be achieved by the following constitution.
(1) a housing;
A rotating shaft disposed in the housing so as to be rotatable relative to the housing and capable of clamping the tool at one end;
A bearing portion that rotatably supports the rotating shaft on the housing;
A rotary joint that is disposed on the other end of the rotating shaft and supplies fluid to a plurality of fluid supply paths formed on the rotating shaft;
A spindle device comprising:
The rotary joint includes a rotating part having a plurality of fluid supply holes respectively communicating with a plurality of fluid supply paths of the rotating shaft,
The rotating part includes a rotating base supported by the housing of the rotary joint, and a rotating connecting part that is detachably bolted to the rotating base and connected to the rotating shaft, and the rotating base and the The rotation connecting part can be separated in the axial direction by releasing the bolt fastening,
The rotation connecting portion is formed with a non-circular portion that is engageable with an end peripheral surface of the rotating shaft, and the end peripheral surface is engaged with the non-circular portion so that the rotating portion is A spindle device that rotates integrally with a rotating shaft .
( 2 ) The rotary connecting portion includes a first center hole formed at an axial center thereof, a second center hole that is continuous with the first center hole on the tool side, and has a larger diameter than the first center hole; The spindle apparatus according to (1) , further comprising: an axial through-hole extending in the axial direction around the first central hole in parallel with the first central hole and opening in the second central hole. .
( 3 ) The spindle device according to ( 2 ), wherein the non-circular portion is formed in the first center hole.
( 4 ) The housing includes an intermediate housing to which a stator is attached, and a front housing detachably fastened to the intermediate housing.
The rotating shaft has a rotor arranged to face the stator,
The bearing portion includes a first bearing portion that supports the rotating shaft on the tool side with respect to the rotor, and a second bearing portion that supports the rotating shaft on the counter tool side with respect to the rotor,
In the housing, an outer ring of a bearing of the second bearing portion is fitted, and a bearing sleeve having an outer diameter smaller than the inner diameter of the stator is provided.
The subassembly having the front housing, the rotating shaft, the rotor, the first bearing portion, the second bearing portion, and the other bearing sleeve releases the fastening between the front housing and the intermediate housing. Thus, the spindle device according to any one of (1) to ( 3 ), wherein the spindle device can be integrally extracted from the intermediate housing to the tool side.

  According to the spindle device of the present invention, the plurality of fluid supply holes formed in the rotary joint are respectively communicated with the plurality of fluid supply paths of the rotating shaft to supply fluid to the plurality of fluid supply paths. Since the rotary joint includes a rotating portion that can be separated in the axial direction, when a failure occurs in the rotating portion of the rotary joint connected to the rotating shaft, the rotary joint is not disassembled and the entire rotating portion is replaced. Maintenance can be easily performed by removing and replacing a part of the rotating part. Further, since the rotating part having a plurality of fluid supply holes can be manufactured separately, the plurality of fluid supply holes can be easily processed.

It is a longitudinal cross-sectional view of the spindle apparatus which is 1st Embodiment of this invention. It is an enlarged view of the rotary joint in FIG. FIG. 2 is an enlarged view of a portion surrounded by a circle A in FIG. 1. It is sectional drawing which shows the modification of the flow path between the rotating shaft and rotor sleeve of this invention. It is sectional drawing for demonstrating the modification of the spindle apparatus which comprises a some fluid supply path. It is a longitudinal cross-sectional view of the spindle apparatus which is 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the spindle apparatus which is 3rd Embodiment of this invention. It is the schematic of the testing apparatus for confirming the effect of this invention. (A) is an enlarged view of the axial end part of FIG. 8, (b) is a figure which shows the insertion position of a shim. It is a longitudinal cross-sectional view of the conventional spindle apparatus. It is a longitudinal cross-sectional view of another conventional spindle device. It is a longitudinal cross-sectional view of the conventional rotary joint.

Explanation of symbols

10, 100, 160 Spindle device 11, 111 Housing 12, 112 Rotating shaft 13, 113 First bearing portion (bearing portion)
14,114 Second bearing part (bearing part)
15, 115 Rotor sleeve 21 Rotary joint 29 Rotating base 30 Draw bar 30d Small diameter hole (first fluid supply path)
30e hole (second fluid supply path)
40,140 flow path (second fluid supply path)
44 Rotating connecting portion 45 Second center hole (second fluid supply hole)
46 1st center hole (1st fluid supply hole)
46a Non-circular portion 47 Axial through hole (second fluid supply hole)
50 fastening mechanism 51 taper ring 51b taper surface 52 clamping ring 61 motor 63 rotor

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

(First embodiment)
1 is a longitudinal sectional view of a spindle device according to a first embodiment of the present invention, FIG. 2 is an enlarged view of a rotary joint in FIG. 1, and FIG. 3 is an enlarged view of a portion surrounded by a circle A in FIG. It is. In FIG. 1, the upper half shows a tool unclamped state, and the lower half shows a tool clamped state.

  As shown in FIG. 1, the spindle device 10 is disposed between a housing 11, a rotation shaft 12 disposed in the housing 11 so as to be rotatable relative to the housing 11, and the housing 11 and the rotation shaft 12. A motor 61, a first bearing portion 13 that rotatably supports the rotary shaft 12 on the tool side (one end side) with respect to the rotor 63 of the motor 61, and an anti-tool side (other end side) with respect to the rotor 63. A second bearing portion 14 that rotatably supports the rotating shaft 12; a rotor sleeve 15 that is detachably fitted to the rotating shaft 12 between the first bearing portion 13 and the second bearing portion 14; A hydraulic unclamping mechanism portion 32 that is disposed at an end portion on the counter tool side and applies an unclamping force to the rotary shaft 12 by hydraulic pressure, and a rotary joint 21 that supplies fluid to the rotary shaft 12 is provided.

  The housing 11 is attached to the machine tool main body, and supports a front housing 11a that rotatably supports the front portion of the rotary shaft 12 via the first bearing portion 13, and a rear portion of the rotary shaft 12 via the second bearing portion 14. The rear housing 11c is rotatably supported, and the intermediate housing 11b is disposed between the front housing 11a and the rear housing 11c. A bearing sleeve 70 that is slidable in the axial direction with respect to the rear housing 11c is fitted in the rear housing 11c. A front lid 16 and a front cover 17 are provided at the front end of the front housing 11a.

  A motor 61 is built in between the intermediate housing 11 b of the housing 11 and the axial intermediate portion 12 a of the rotating shaft 12. The stator 62 of the motor 61 is fitted and fixed to the intermediate housing 11b. In addition, the rotor 63 of the motor 61 disposed opposite to the stator 62 is externally fixed to the rotor sleeve 15 by shrink fitting. Both ends of the rotor sleeve 15 are externally fitted and fixed to the axial intermediate portion 12a of the rotary shaft 12 by a fastening mechanism 50 described later.

  The first bearing portion 13 and the second bearing portion 14 include a plurality of angular ball bearings 26 (four first bearing portions 13 and two second bearing portions 14). The angular ball bearing 26 is a rolling element disposed between the outer ring 22 fitted inside the front housing 11 a and the bearing sleeve 70 of the housing 11, the inner ring 23 fitted outside the rotary shaft 12, and the outer ring 22 and the inner ring 23. Each ball 24 is provided and is regulated in the axial direction by a plurality of spacers 25. In addition, although the angular ball bearing is used as the 1st bearing part 13 and the 2nd bearing part 14, various bearings can be used in arbitrary combinations.

  The axial hole 27 formed through the axial center of the rotary shaft 12 has a draw bar 30 mounted so as to be movable relative to the rotary shaft 12 in the axial direction, and the draw bar 30 moves the tool holder 18 inward in the axial direction. A spring 31 is disposed so as to be drawn in, and is arranged so as to be compressible between the rotary shaft 12 and the large-diameter portion 30a of the draw bar 30 in the axial direction. In addition, although the disc spring is used as the spring 31, you may use a coil spring, a helical disc spring, etc.

  A collet portion 20 that clamps the tool holder 18 is formed at the tip of the draw bar 30, and this tool holder 18 is fitted with a tapered hole 19 provided in the axial front portion of the rotary shaft 12 in the clamped state. To do. Further, a hydraulic unclamp mechanism 32 for pushing the draw bar 30 toward the tool holder 18 when unclamping is disposed at the rear end of the draw bar 30.

  2, the hydraulic unclamping mechanism 32 also includes a cylinder 34 having a first pressure oil supply port 33A and a second pressure oil supply port 33B, and a piston 35 movably fitted in the cylinder 34. Is provided. When pressure oil supplied from a hydraulic pump (not shown) is supplied from the first pressure oil supply port 33A to the cylinder 34, the piston 35 moves in the left direction in the figure to push the draw bar 30 toward the tool holder 18 and unclamped. And When pressure oil is supplied to the second pressure oil supply port 33 </ b> B, the piston 35 moves in the right direction, and the draw bar 30 clamps the tool holder 18.

  Further, the front and rear portions of the rotary shaft 12 are provided with axial holes 41A and 41B formed from the front and rear ends in the axial direction toward the center in the axial direction, the outer peripheral surface of the rotary shaft 12 and the respective axial holes 41A. , 41B and the radial holes 42A, 42B are formed. Further, on the outer peripheral surface of the axial intermediate portion 12a of the rotary shaft 12, a groove portion 43 is formed in the axial direction so that the radial holes 42A and 42B communicate with each other on the outer peripheral surface. Furthermore, an axial hole 41C formed from the front end toward the axial center and a radial hole 42C communicating the axial hole 30d and the axial hole 41C of the draw bar 30 are formed at the front portion of the rotary shaft 12. It is formed in a phase different from that of the axial hole 41A and the radial hole 42A.

  The rotor sleeve 15 is externally fitted and fixed to the rotary shaft 12 so as to cover the groove 43 formed in the rotary shaft 12. As shown in FIG. 3, a fastening mechanism 50 is disposed on the outer peripheral surface of both ends of the rotor sleeve 15, and the rotor sleeve 15 is fastened and fixed to the outer peripheral surface of the rotating shaft 12. As the fastening mechanism 50, a Span ring (trade name) manufactured by Ring Feder in Germany, which has a taper ring 51 and a pair of clamping rings 52, is known. The taper ring 51 has an inner diameter of the inner peripheral surface 51a that is the same as the outer diameter of the rotor sleeve 15. The outer peripheral surface is provided with a pair of tapered surfaces 51b having different inclination directions, and is formed in a substantially chevron shape. ing. The pair of sandwiching rings 52 has a tapered inner peripheral surface 52 a having the same angle as the tapered surface 51 b of the tapered ring 51, and is engaged with the tapered surface 51 b of the tapered ring 51. The pair of sandwiching rings 52 are fastened by bolts 53, and are pressed and pressed in the axial direction by the bolts 53.

  In such a fastening mechanism 50, the rotor sleeve 15 is fitted onto the rotary shaft 12 so as to cover the groove 43 formed on the rotary shaft 12, and then a bolt 53 is screwed to bring the pair of tapering rings 51 in the axial direction. Move relative (approach). Thus, the rotor sleeve 15 is tightened by generating a radial tightening force (diameter reducing force) by the action of the tapered surface 51b. As a result, the inner peripheral surface of the rotor sleeve 15 is reduced in diameter so as to be in close contact with and fixed to the outer peripheral surface of the rotary shaft 12, and the space between the outer peripheral surface of the rotary shaft 12 and the inner peripheral surface of the rotor sleeve 15 is sealed. .

  Therefore, the fluid passes through the space formed between the groove 43 of the rotary shaft 12 and the inner peripheral surface of the rotor sleeve 15, and the flow path (second fluid supply passage) 40 through which the fluid passes. Is constituted by a space between the groove 43 and the inner peripheral surface of the rotor sleeve 15, and axial holes 41A and 41B and radial holes 42A and 42B. An O-ring 54 is disposed between the rotor sleeve 15 and the rotating shaft 12 on the outer side in the axial direction of the groove 43, and seals the gap between them. Further, instead of forming the groove portion 43, the axial intermediate portion 12a of the rotary shaft 12 has an entire outer peripheral surface smaller in diameter than the inner peripheral surface of the rotor sleeve 15, as shown in FIG. An annular space S that is continuous with the circumferential direction in the circumferential direction may be formed. Further, the groove 43 and the annular space S may be configured by processing the inner peripheral surface of the rotor sleeve 15.

  On the side opposite to the tool from the rotor 63 of the rotating shaft 12, the second bearing portion 14, the bearing sleeve 70 fitted to the second bearing portion 14, the detected portion 72 constituting the speed sensor 71, and the detected portion 72 together with the detected portion 72 The nut 73 etc. which fix the inner ring | wheel 23 of the bearing 26 of the 2 bearing part 14 are attached, and all are set smaller than the internal diameter of the stator 63. FIG.

  The front housing 11a is detachably fastened to the intermediate housing 11b with a bolt (not shown), and the front housing 11a in which the first bearing portion 13 is incorporated and the draw bar 30 are incorporated by releasing the fastening of the bolt. The subassembly U including the rotating shaft 12, the rotor 63, the second bearing portion 14, the bearing sleeve 70, and the like can be extracted from the intermediate housing 9 as one body.

  As shown in FIG. 2, the rotary joint 21 is connected to the inner peripheral surface 36 of the cylinder 34 by inlay fitting at the rear end of the hydraulic unclamp mechanism 32. The rotary joint 21 is provided with a plurality of supply ports such as a seating air supply port 38 to which air as a second fluid is supplied and a coolant supply port 39 to which coolant as a first fluid is supplied, which are not illustrated. Fluid (air, coolant) is supplied from a fluid supply source.

  The rotary joint 21 includes a rotation connecting portion 44 that is fixed to the rotation base portion 29 of the rotary joint 21 by a bolt 37. The rotation base 29 is rotatably supported on the housing of the rotary joint 21 by a rolling bearing (not shown). The rotation connecting portion 44 can be easily separated from the rotation base portion 29 incorporated in the housing of the rotary joint 21 by removing the bolt 37, and is inserted into the center hole of the piston 35 of the hydraulic unclamping mechanism portion 32. Yes. The rotation base 29 and the rotation connecting portion 44 constitute a rotation portion.

  The rotation base 29 includes a coolant hole 81 to which the coolant from the coolant supply port 39 is supplied, and an air hole 82 to which air from the seating air supply port 38 is supplied. The coolant hole 81 extends toward the tool side. The protrusion 83 is open.

  The rotation connecting portion 44 is formed at the center in the axial direction, and is continuous with the first center hole 46 into which the protruding portion 83 of the rotation base 29 is inserted, the first center hole 46 on the tool side, and the first center hole. A second central hole 45 having a diameter larger than 46, and an axial through-hole 47 extending in the axial direction around the first central hole 46 in parallel with the first central hole 46 and opening in the second central hole 45. Prepare.

  The coolant hole 81 is connected to the small diameter hole 30 d formed in the axial center of the draw bar 30 constituting the first fluid supply path 84 of the rotating shaft 12 through the first center hole 46. The air hole 82 is connected to a hole 30 e formed around the small diameter hole 30 d of the draw bar 30 through the axial through hole 47 and the second center hole 45. This hole 30e constitutes the second fluid supply path 85 of the rotating shaft 12 together with the flow path 40 described above. The coolant hole 81 and the first center hole 46 constitute a first fluid supply hole of the rotary joint 21, and the air hole 82, the axial through hole 47, and the second center hole 45 are the first fluid supply holes of the rotary joint 21. 2 fluid supply holes are formed.

  The first center hole 46 is partially formed with a non-circular portion 46a such as a hexagon or an octagon, and a non-circular shaft having a substantially identical outer peripheral surface formed at the rear end portion of the draw bar 30. The portion 30c is fitted so as to be movable in the axial direction. Thereby, the rotation of the rotary shaft 12 driven by the motor 61 rotates the rotary connecting portion 44 and the rotary base portion 29 through the fitting of the non-circular shaft portion 30c and the non-circular portion 46a that are fitted to each other.

  The tool side part from the non-circular part 46a of the first center hole 46 is formed in a cylindrical shape, and is fitted to the small diameter side cylinder part 30f of the draw bar 30 so as to be movable in the axial direction. The draw bar 30 is fitted to a large-diameter side cylinder portion 30b formed on the tool side from the small-diameter side cylinder portion 30f so as to be movable in the axial direction. Further, between the first center hole 46 and the small diameter side cylinder part 30f and between the second center hole 45 and the large diameter side cylinder part 30b, sealing members 48 and 49 such as O-rings and U packings are provided. Is arranged.

  Therefore, a plurality of fluids of the rotary joint 21 are formed by forming stepped holes (the first center hole 46 and the second center hole 45) in the rotary connecting portion 44 and using the draw bar 30 as a stepped shaft and fitting each other. The supply hole and the plurality of fluid supply paths 84 and 85 of the rotating shaft 12 can be connected and connected simultaneously.

  Thus, the plurality of fluids are supplied through the independent flow paths. The seal members 48 and 49 are not limited to O-rings and U-packings, and suitable materials such as fluorine rubber, acrylic rubber, and nitrile rubber can be used.

  Thereby, the coolant liquid supplied from the coolant supply port 39 of the rotary joint 21 constitutes the coolant hole 81 of the rotation base portion 29, the first center hole 46 of the rotation connection portion 44, and the first fluid supply path 84. It is supplied to the tool holder 18 through a small-diameter hole 30d passing through the axis of 30 and ejected to the tool.

  Further, the air supplied from the seating air supply port 38 of the rotary joint 21 passes through the air hole 82 of the rotation base 29, the axial through hole 47 and the second center hole 45 of the rotation connection part 44, and the second fluid supply path. The hole 30e of the draw bar 30, the flow path 40 (the axial hole 41B, the radial hole 42B, the space formed between the groove 43 and the inner peripheral surface of the rotor sleeve 15, the radial hole 42A, the axial hole 41A) and is supplied to the seating detection nozzle 28 provided at the front end of the spindle device 10, and it is detected that the seating of the tool has been normally performed by the pressure change.

  The fluid is not limited to coolant liquid or air, and radial holes (not shown) that communicate with the first bearing portion 13 and the second bearing portion 14 from the axial holes 41A and 41B are provided. The first bearing portion 13 and the second bearing portion 14 can be lubricated by supplying lubricating oil via the rotary joint 21. In addition, as shown in FIG. 5, a plurality of sets of axial holes 41 </ b> A and 41 </ b> B, radial holes 42 </ b> A and 42 </ b> B, and grooves 43 are separated in the circumferential direction of the rotating shaft 12 and are provided in parallel with each other , 40 ′, different types of fluids (for example, cutting fluid, compressed air, lubricating oil) can be simultaneously supplied to different parts. In this case, the flow path 40 ′ formed between the adjacent flow paths 40 is configured by communicating the small diameter hole 30 d of the draw bar 30 and the radial hole 42 B of the flow path 40 ′.

  Therefore, according to the spindle device 10 of the present embodiment, the rotary joint 21 is formed on the rotary joint 21 by the rotary connecting portion 44 that is separable in the axial direction from the rotary base 29 that is rotatably supported by the housing of the rotary joint 21. Since the first and second fluid supply holes and the first and second fluid supply paths 84 and 85 formed in the rotary shaft 12 are connected to supply the fluid, the rotation of the rotary joint 21 is performed. When a problem occurs in the portion, the rotary joint 21 can be removed and maintenance can be easily performed without disassembling the rotary joint 21 and replacing the entire rotating portion. Moreover, since the rotation connection part 44 can be manufactured separately when manufacturing the rotation connection part 44, the several holes 45, 46, and 47 can be processed easily.

  Moreover, according to the spindle apparatus 10 of the present embodiment, the rotary joint 21 is separated from the draw bar 30 in the axial direction by removing the mounting bolt 90 in the housing of the rotary joint 21, and the entire rotary joint 21 is hydraulically unclamped. When only the rotary joint breaks down and can be separated from the part 32, the maintenance is very easy.

  Further, by inserting and engaging the non-circular shaft portion 30c of the draw bar 30 with the non-circular portion 46a formed in the first central hole 46 of the rotary connecting portion 44, a plurality of fluid supply paths of the rotary shaft 12 can be easily obtained. 84 and 85 and the plurality of fluid supply holes of the rotary joint 21 can be communicated with each other and can be coupled so as to be integrally rotatable.

  The rotating part includes a rotating base 29 supported by the housing of the rotary joint 21 and a rotating connecting part 44 connected to the rotating shaft 12. The rotating connecting part 44 is detachably bolted to the rotating base 29. If it does so, the rotation connection part 44 can be easily removed from the rotation base 29, and maintainability will improve significantly. Further, a non-circular portion 46a is formed in the rotary connecting portion 44, the draw bar 30 is inserted into the non-circular portion 46a and engaged with the peripheral surface of the end portion, and the rotary connecting portion 44 and the draw bar 30 are connected so as to be integrally rotatable. Therefore, the non-circular shaft portion 30c of the draw bar 30 is inserted into the non-circular portion 46a of the rotary connecting portion 44, and the phase alignment between the rotary connecting portion 44 and the rotary shaft 12 is easily performed.

  The rotation connecting portion 44 includes a first center hole 46 formed at the center in the axial direction, a second center hole 45 that is continuous with the first center hole 46 on the tool side, and has a larger diameter than the first center hole 46. And an axial through-hole 47 extending in the axial direction around the first center hole 46 in parallel with the first center hole 46 and opening in the second center hole 45. Thereby, the plurality of fluid supply paths 84 and 85 of the rotary shaft 12 and the plurality of fluid supply holes of the rotary joint 21 including the rotary connection portion 44 can be easily communicated with each other via the rotary connection portion 44. A plurality of fluids are supplied independently.

  Furthermore, since the non-circular portion 46a is formed in the first center hole 46, the rotary connecting portion 44 and the draw bar 30 can be integrally rotated without increasing the axial length of the rotary connecting portion 44.

  Further, according to the spindle device 10 of the present embodiment, the rotor sleeve 15 that is externally fitted to the rotary shaft 12 is provided between the first bearing portion 13 and the second bearing portion 14, and fluid passes through the rotary shaft 12. Since the flow path 40 includes a space provided between the outer peripheral surface of the rotating shaft 12 and the inner peripheral surface of the rotor sleeve 15 that are fitted to each other, processing of a small diameter and long through hole that is difficult to process becomes unnecessary, The flow path 40 through which the fluid passes through the rotary shaft 12 can be processed easily and at low cost, and the flow path 40 having a simple configuration is inexpensive. Further, since the flow path 40 is configured by using the rotor sleeve 15 to which the motor built-in type rotor 63 is externally fitted, the rotation shaft that becomes longer in the axial direction by externally fitting the motor 61 without increasing the number of parts. The twelve flow paths 40 can be processed easily and at low cost.

  In addition, a space that is a part of the flow path 40 through which the fluid passes through the rotary shaft 12 includes an outer peripheral surface of the rotary shaft 12 and an inner peripheral surface of the rotor sleeve 15 that are fitted to each other, and the rotor sleeve 15 is fastened. Since it is detachably fixed to the rotating shaft 12 by the mechanism 50, the rotor 63 can be easily attached to and detached from the rotating shaft 12 together with the rotor sleeve 15, and the maintainability is greatly improved.

  Further, if the rotor 63 is externally fitted and fixed to the rotor sleeve 15 by shrink fitting, the rotor 63 and the rotor sleeve 15 can be handled easily as substantially one part.

  Further, a fastening mechanism 50 having a taper ring 51 having a pair of tapered surfaces 51 b on the outer peripheral surface and a pair of clamping rings 52 respectively engaged with the taper surfaces 51 b of the taper ring 51 around the rotor sleeve 15. And the rotor sleeve 15 is tightened by the reduced diameter force generated when the pair of sandwiching rings 52 are pressed in the axial direction, and the outer peripheral surface of the rotary shaft 12 and the inner peripheral surface of the rotor sleeve 15 are sealed. Thus, the rotor sleeve 15 can be easily attached to and detached from the rotating shaft 12 by fixing. Thus, when maintenance is required, such as foreign matter entering a space (flow path) formed between the outer peripheral surface of the rotating shaft 12 and the inner peripheral surface of the rotor sleeve 15, the rotor sleeve 15 can be easily removed. It can be removed from the rotating shaft for maintenance.

(Second Embodiment)
FIG. 6 is a longitudinal sectional view of a spindle device according to the second embodiment of the present invention. As shown in FIG. 6, the spindle device 100 is disposed between the housing 111, the rotation shaft 112 disposed in the housing 111 so as to be rotatable relative to the housing 111, and the housing 111 and the rotation shaft 112. A plurality of (two in this embodiment) first bearing portions 113 on the tool side, a plurality of (two in this embodiment) second bearing portions 114 on the counter tool side, and a first and second bearing portions 113 and 114 are provided with a sleeve 115 that is externally fitted to the axially intermediate portion 112a of the rotary shaft 112.

  The housing 111 is attached to the machine tool main body, and supports a front housing 111a that rotatably supports the front portion of the rotating shaft 112 via the first bearing portion 113, and a rear portion of the rotating shaft 112 via the second bearing portion 114. The rear housing 111c is rotatably supported, and the intermediate housing 111b is disposed between the front housing 111a and the rear housing 111c. A front lid 116 and a front cover 117 are provided at the front end of the front housing 111a.

  The rotary shaft 112 has small-diameter shaft portions 112b and 112c having a smaller diameter than the axial intermediate portion 112a at the front and rear portions in the axial direction, and a tapered hole 119 for attaching the tool holder 118 is provided in the small-diameter shaft portion 112b. . In addition, a pulley 152 around which the belt 151 is suspended is externally fitted and fixed to the small diameter shaft portion 112c to drive the rotary shaft 112. Further, a bolt or the like (not shown) is attached to the rear end of the small diameter shaft portion 112c. A rotary joint 121 is connected through a fixed disk member 120.

  Each of the bearing portions 113 and 114 includes an outer ring 122 fitted into the front housing 111a and the rear housing 111c of the housing 111, an inner ring 123 fitted into the small diameter shaft portions 112b and 112c of the rotating shaft 112, and an outer ring 122 and an inner ring. Balls 124 that are rolling elements disposed between the first and second rollers 123 are provided, and are regulated in the axial direction by a plurality of spacers 125 and nuts 126. In addition, although the angular contact ball bearing is used as the bearing parts 113 and 114, various bearings can be used in arbitrary combinations.

  Inside the rotary shaft 112, a draw bar 130 that is mounted on the rotary shaft 112 so as to be relatively movable in the axial direction, and the draw bar 130 is externally attached to the draw bar 130 so as to draw the tool holder 118 inward in the axial direction. A spring 131 is disposed between the rotary shaft 112 and the large-diameter portion 130a of the draw bar 130 so as to be compressible. In addition, although the disc spring is used as the spring 131, a coil spring, a helical disc spring, etc. may be used.

  A collet portion 133 that holds the ball 132 and clamps the pull stud 118 a of the tool holder 118 is formed at the tip of the draw bar 130. An unclamp bar 153 is fixed to the rear end of the draw bar 130 so as to protrude from an opening 154 formed in the small-diameter shaft portion 112c. When the tool holder 118 is replaced, the unclamp bar 153 is moved forward in the axial direction. The draw bar 130 is pushed out to the tool holder 118 side, and the ball 132 is moved to the clamp recess 112e located behind the tapered hole 119.

  Further, the front and rear portions of the rotating shaft 112 are provided with axial holes 141A and 141B formed from the front and rear ends in the axial direction toward the center in the axial direction, the outer peripheral surface of the rotating shaft 112 and the respective axial holes 141A. , 141B to communicate with each other in the radial direction 142A, 142B. Further, a groove portion 143 is formed in the axial direction on the outer peripheral surface of the axial intermediate portion 112a of the rotating shaft 112 so that the radial holes 142A and 142B communicate with each other on the outer peripheral surface.

  The sleeve 115 is externally fitted to the rotary shaft 112 so as to cover the groove 143 formed on the rotary shaft 112, and abuts on the annular convex portion 112 f formed on the outer peripheral surface of the axial intermediate portion 112 a of the rotary shaft 112. As a result, it is positioned in the axial direction. Further, an O-ring 144 is disposed between the sleeve 114 and the rotating shaft 112 on the outer side in the axial direction of the groove portion 143. Thereby, the flow path 140 through which the fluid passes through the rotating shaft 112 includes the axial holes 141A and 141B, the radial holes 142A and 42B, and the space formed between the groove 143 and the inner peripheral surface of the sleeve 115. Consists of.

  Further, the disc member 120 fixed to the rear end of the rotating shaft 112 is formed with a fluid distribution hole 146 branched from the central hole 145 provided at the center, and the central hole 145 is formed in the rotary joint 121. The fluid supply port 147 communicates.

  Thereby, the cutting fluid supplied through the fluid supply port 147 of the rotary joint 121, the central hole 145 of the disk member 120, and the fluid distribution hole 146 is the axial hole 141B, the radial hole 142B, and the groove portion which are the flow paths 140. 143, the radial hole 142A, and the axial hole 141A pass in this order, and are ejected to the tool 150 through the cutting fluid channel 118b provided in the tool holder 118.

  The fluid and the predetermined portion to which the fluid is supplied are not limited to the cutting fluid and the cutting fluid flow path 118b, but the radial direction communicating with the respective bearing portions 113 and 114 from the axial holes 141A and 141B. A hole (not shown) may be provided, and lubricating oil may be supplied via the rotary joint 121 and the disk member 120 to lubricate the bearing portions 113 and 114. Furthermore, a flow path (not shown) communicating from the axial hole 141A to the tapered hole 119 may be provided, and compressed air may be supplied from the rotary joint 121 and the disk member 120 to clean the tapered hole 119. .

  Furthermore, a plurality of sets of axial holes 141A and 141B, radial holes 142A and 142B, and groove portions 143 are provided, and a plurality of flow paths 140 provided to be spaced apart in the circumferential direction of the rotating shaft 112 provide different types of fluids (for example, , Cutting fluid, compressed air, lubricating oil) can be simultaneously supplied to different parts.

  According to the spindle device 100 of the present embodiment, the flow path 140 through which the fluid passes through the rotation shaft 112 is provided between the first and second bearing portions 113 and 114 and has the sleeve 115 fitted to the rotation shaft 112. Since a space provided between the outer peripheral surface of the rotating shaft 112 and the inner peripheral surface of the sleeve 115 that are fitted to each other is included, it is not necessary to process a small-diameter and long through-hole that is difficult to process. The passing channel 140 can be processed easily and at low cost, and the channel having a simple configuration is inexpensive.

(Third embodiment)
Next, a spindle device according to a third embodiment of the present invention will be described with reference to FIG. Note that the same parts as those of the second embodiment are denoted by the same reference numerals, and description thereof is omitted or simplified.

  The spindle device 160 of the present embodiment is of a motor built-in type, and similarly to the first embodiment, a housing 111, a rotating shaft 112 disposed in the housing 111 so as to be relatively rotatable with respect to the housing 111, A plurality of (four in the present embodiment) first bearing portions 113 and a plurality (two in the present embodiment) second on the tool side disposed between the housing 111 and the rotating shaft 112. A bearing 114 and a sleeve 115 ′ that is externally fitted to the axial intermediate portion 112 a of the rotating shaft 112 are provided between the plurality of bearings 113 and 114.

  A motor 161 is built in between the intermediate housing 111b of the housing 111 of this embodiment and the axial intermediate portion 112a of the rotating shaft 112, and the stator 162 of the motor 161 is fixed to the intermediate housing 111b. Further, the rotor 163 of the motor 161 is externally fixed to the sleeve 115 'by shrink fitting, that is, the sleeve 115' constitutes a rotor sleeve.

  As in the second embodiment, the rotor sleeve 115 ′ also forms a space together with the groove 143 formed in the rotating shaft 112, and forms a part of the flow path 40 through which the fluid passes through the rotating shaft 112.

  In the present embodiment, the draw bar 130 and the rotary joint 121 are coupled to each other, and the fluid sent from the rotary joint 121 is a shaft hole portion 164 that is drilled radially outward from the axial center portion of the draw bar 130. And is supplied to the axial hole 141B of the rotary shaft 12. Further, an opening groove 165 having a predetermined axial width is formed on the inner peripheral surface of the small diameter shaft portion 112c so as to be able to supply fluid even when the draw bar 130 moves so as to communicate with the axial hole 141B. Is done.

Therefore, according to the spindle device 160 of the present embodiment, the flow path 140 is configured using the rotor sleeve 115 ′ used in the motor built-in type, so that the motor 161 can be externally fitted without increasing the number of parts. By doing so, the flow path 140 of the rotating shaft 112 that is elongated in the axial direction can be processed easily and at low cost.
Other configurations and operations are the same as those of the second embodiment.

  In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

  Here, in the case where the flow path formed in the spindle device of the third embodiment is an air supply path for confirming the adhesion of the tool holder, whether or not the gap detection is possible is shown in FIGS. Tests were performed using the equipment shown.

  The test apparatus 170 is configured with respect to a part constituting the flow path in the spindle apparatus 160 of the third embodiment. The flow path 171 is formed by a draw bar 172, a shaft 173, and a rotor 174, and these members are The shaft 173 is supported by being fixed to the mounting bracket 175. A holder 176 is attached to the tip of the shaft 173, and a clamp member 177 that presses the holder 176 is provided in front of the holder 176.

  And as shown in FIG.9 (b), between the axis | shaft 173 and the holder 176, plate | board thickness (0.010mm-0.040mm) and phase (0 degree, 45 degree, 90 degree with respect to the shaft hole) While inserting a shim 178 having a width of 5 mm, the holder 176 is pressed by the clamp member 177 with a load equivalent to the clamping force to obtain an actual clamping state, and the dial gauge 180 fixed to the magnet stand 179 attached to the shaft 173 is attached. The actual gap amount g was measured.

  In this state, air passing through the air catch sensor 181 (manufactured by SMC) was supplied from the rear part of the draw bar 172 to detect the gap. In this test, the diameter (φA) of the seating hole 173a at the tip of the shaft 173 is 1.5 mm, the pressure value of the air pressure gauge 182 is 0.10 MPa, and the limit setting value of the air catch sensor 181 is 0. It was done as 5. The test results are shown in Table 1.

  As shown in Table 1, under the above conditions, it can be seen that when the actual gap amount g between the shaft 173 and the holder 176 is 0.010 mm or more, the gap detection is surely performed. It was confirmed that it can be used.

  This application is based on a Japanese patent application filed on July 24, 2007 (Japanese Patent Application No. 2007-192142) and a Japanese patent application filed on August 7, 2007 (Japanese Patent Application No. 2007-205385). The contents are incorporated herein by reference.

Claims (4)

A housing;
A rotating shaft disposed in the housing so as to be rotatable relative to the housing and capable of clamping the tool at one end;
A bearing portion that rotatably supports the rotating shaft on the housing;
A rotary joint that is disposed on the other end of the rotating shaft and supplies fluid to a plurality of fluid supply paths formed on the rotating shaft;
A spindle device comprising:
The rotary joint includes a rotating part having a plurality of fluid supply holes respectively communicating with a plurality of fluid supply paths of the rotating shaft,
The rotating part includes a rotating base supported by the housing of the rotary joint, and a rotating connecting part that is detachably bolted to the rotating base and connected to the rotating shaft, and the rotating base and the The rotation connecting part can be separated in the axial direction by releasing the bolt fastening,
The rotation connecting portion is formed with a non-circular portion that is engageable with an end peripheral surface of the rotating shaft, and the end peripheral surface is engaged with the non-circular portion so that the rotating portion is A spindle device that rotates integrally with a rotating shaft . The rotary connecting portion includes a first center hole formed at an axial center thereof, a second center hole that is continuous with the first center hole on the tool side, and has a larger diameter than the first center hole, and the first center hole. 2. The spindle device according to claim 1 , further comprising: an axial through hole that extends in the axial direction around the center hole in parallel with the first center hole and opens into the second center hole. The spindle device according to claim 2 , wherein the non-circular portion is formed in the first center hole. The housing includes an intermediate housing to which a stator is attached, and a front housing that is detachably fastened to the intermediate housing,
The rotating shaft has a rotor arranged to face the stator,
The bearing portion includes a first bearing portion that supports the rotating shaft on the tool side with respect to the rotor, and a second bearing portion that supports the rotating shaft on the counter tool side with respect to the rotor,
In the housing, an outer ring of a bearing of the second bearing portion is fitted, and a bearing sleeve having an outer diameter smaller than the inner diameter of the stator is provided.
The front housing, said rotary shaft, said rotor, said first bearing portion, the second bearing portion, and the sub-assembly having a bearing sleeve, by releasing the engagement between the said front housing intermediate housing the spindle apparatus according to any one of claims 1 to 3, characterized in that it is possible withdrawn integrally from the intermediate housing to the tool side.

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