JP2016026900A - Spindle device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spindle device having a high speed rotation function, which achieves a dmn value of one million or higher, and a good waterproof function.SOLUTION: A flinger 40 includes: a boss part 41 which fits on a rotary shaft 11; and a disk part 42 which extends from the boss part 41 to the radial outer side. An outer periphery part of the disk part 42 forms a tip part of the flinger 40. The outer periphery part of the disk part 42 faces an axial end surface of a housing H in an axial direction through a small clearance. At least a part of the flinger 40 is formed by a carbon fiber composite material. A protruding part 44 which protrudes to the side of an outer ring presser 12 is formed on a surface of a radial intermediate part of the disk part 42 which faces the outer ring presser 12.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a spindle device, and more particularly to a spindle device having a flinger.

  In a spindle apparatus applied to a machine tool or the like, a workpiece is cut or ground by rotating a rotating shaft to which a tool is attached at high speed. In machining, a large amount of machining fluid is generally supplied to the machining site for the purpose of lubricating and cooling the tool and the machining site. That is, lubrication can improve the machining characteristics, suppress wear on the cutting edge, extend the tool life, and the like. In addition, the thermal expansion of the tool and the workpiece is suppressed by cooling, so that the machining accuracy is improved, the thermal welding of the machining part is prevented, the machining efficiency is improved, and the surface property of the machined surface is improved. Since the distance between the spindle device and the processing part is close, a large amount of processing liquid is also applied to the front surface of the spindle device. If this working fluid enters the inside of the bearing, it may cause poor lubrication or seizure of the bearing, so the waterproof performance of the bearing becomes important. In particular, in bearings that are lubricated with grease or lubricated with grease, the inside of the bearing is at a lower pressure than oil / air lubricated or oil mist lubricated bearings that are supplied with lubricating oil along with air. It is easy to intrude into and requires higher waterproof performance.

As a general waterproof mechanism, a contact seal such as an oil seal or a V ring is known. However, when this contact type seal is applied to a spindle device used at a high speed rotation with a dmn value of 400,000 or more (more preferably 500,000 or more), heat generated from the contact part of the contact type seal is large. Contact seals cannot be used in spindle devices because the seals wear out in a short time.
For this reason, in a machine tool, a so-called labyrinth is a non-contact seal in which a flinger is fixed to a front end portion (tool side) of a spindle device so as to be able to rotate integrally with a rotary shaft, and a gap between the flinger and a housing is reduced. The seal is made to be waterproof. The flinger that rotates at high speed, together with the labyrinth effect, swings the working fluid that has fallen on the flinger outward in the radial direction by centrifugal force to prevent the working fluid from entering the bearing.

  The waterproofing effect using the flinger's centrifugal force and labyrinth effect increases the centrifugal force by increasing the rotation speed and using a large-diameter flinger, and the gap between the flinger and the housing is as small and long as possible. It is effective. However, when rotating at a high speed or increasing the diameter of the flinger, the centrifugal force and the hoop stress acting on the flinger also increase in proportion thereto.

  Also, as a spindle device for machine tools, a fiber layer wrapped with fibers having a small specific gravity and a large longitudinal elastic modulus is provided in the groove formed on the outer peripheral surface of the tool mounting side end portion to suppress the expansion of the spindle Is disclosed (for example, see Patent Document 1).

Japanese Patent No. 3262395

  In general, the flinger is made of a metal material having a relatively large specific gravity such as an SC material, an SCM material, a SUS material, an AL material, or a CU material. Therefore, if the diameter of the flinger is increased in order to apply a large centrifugal force to the working fluid falling on the flinger, a large centrifugal force acts on the flinger itself, particularly on the outer diameter side. In high-speed rotation with a dmn value of 1 million or more, such as the rotation axis of a machine tool, the flinger may be deformed by centrifugal force, or in extreme cases, the centrifugal force may exceed the tensile strength of the flinger and cause destruction. There is. For this reason, it is necessary to limit the diameter of a flinger and the rotational speed of a rotating shaft to such an extent that the influence of centrifugal force is allowed.

  In a conventional spindle device used in an environment where the dmn value is 1 million or more, the radial dimension of the flinger is limited in consideration of the centrifugal force, so there is room for improvement in terms of waterproof performance. there were.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a spindle device having a dmn value of 1 million or more and capable of high-speed rotation and a good waterproof function.

The above object of the present invention can be achieved by the following constitution.
(1) A housing having an outer cylinder fitted over the outer ring of the bearing, and an outer ring presser fixed to the axial end surface of the outer cylinder and positioning the outer ring in the axial direction;
A rotating shaft supported by the housing via the bearing so as to be relatively rotatable;
A spindle device including a flinger that is fixed to the periphery of the rotary shaft so as to be integrally rotatable and forms a labyrinth seal with the outer ring presser,
The flinger includes a boss part fitted on the rotating shaft and a disk part extending radially outward from the boss part, and an outer peripheral part of the disk part constitutes a tip part of the flinger. And
The outer peripheral portion of the disk portion is opposed to the axial end surface of the outer ring retainer in the axial direction through a slight gap,
In the middle of the disk portion in the radial direction, a convex portion that protrudes toward the outer ring pressing side is formed on the surface facing the outer ring pressing,
At least a part of the flinger is formed of a carbon fiber composite material.

According to the spindle device described in the above (1), since at least a part of the flinger is formed from a carbon fiber composite material, the centrifugal force is reduced by reducing the mass as compared with the metal. The effect on the flinger can be reduced. Moreover, since the tensile strength is higher than that of metal, deformation due to centrifugal force can be further suppressed. As a result, the rotating shaft can be rotated at a high speed, and the size restriction on the flinger can be greatly relaxed and the radial length can be increased. Is obtained. In addition, by reducing the weight of the flinger, the inertia in the rotational direction is reduced, the acceleration / deceleration time can be shortened, the cycle time can be shortened, and an improvement in production efficiency can be expected. In addition, the mass of the tip of the rotating shaft is reduced, the eigenvalue of the rotating shaft can be increased, the shaft can be rotated at higher speed, and vibration during high-speed rotation can also be reduced.
In addition, a convex part that protrudes toward the outer ring presser side is formed on the surface in the radial direction of the disk part on the surface facing the outer ring presser, so that the labyrinth part can be made longer and the prevention performance is improved. can do.

  Further, the flinger includes a boss part fitted on the rotation shaft, and a disk part extending radially outward from the boss part, and an outer peripheral part of the disk part constitutes a tip part of the flinger, The outer peripheral part of the disk part is opposed to the axial end face of the outer ring retainer in the axial direction with a slight gap. As a result, even if machining fluid or dust enters the labyrinth site, the machining fluid or dust can be discharged from the outer periphery of the disk part to the outside due to the flinging off effect of the flinger's centrifugal force. It is possible to prevent dust from entering. In addition, for example, by using it as a vertical spindle device that processes the tool downward, the machining liquid that has entered the labyrinth part can be discharged from the outer periphery of the disk part when stopped, and the machining liquid can enter the labyrinth part. It is possible to prevent the stagnation.

It is sectional drawing of the spindle apparatus which concerns on 1st Embodiment of this invention. (A) is a fragmentary sectional view of the spindle apparatus which concerns on the modification of 1st Embodiment, (b) is a fragmentary sectional view of the spindle apparatus which concerns on the other modification of 1st Embodiment. It is a principal part enlarged view of the spindle apparatus which concerns on 2nd Embodiment of this invention. It is a principal part enlarged view of the spindle apparatus which concerns on 3rd Embodiment of this invention. It is a principal part enlarged view of the spindle apparatus which concerns on 4th Embodiment of this invention. It is a principal part enlarged view of the spindle apparatus which concerns on 5th Embodiment of this invention.

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

  As shown in FIGS. 1 and 2, the spindle device 10 of the present embodiment is a motor built-in spindle device for a machine tool, and a rotating shaft 11 has two rows of front bearings that support the tool side (front side). 50 and 50 and two rows of rear bearings 60 and 60 that support the non-tool side (rear side) are rotatably supported by the housing H. The housing H is composed of a front bearing outer ring retainer 12, an outer cylinder 13, and a rear housing 14 in this order from the tool side.

  Each front bearing 50 is an angular ball bearing having an outer ring 51, an inner ring 52, a ball 53 as a rolling element arranged with a contact angle, and a cage (not shown). Is an angular ball bearing having an outer ring 61, an inner ring 62, balls 63 as rolling elements, and a cage (not shown). The front bearings 50 and 50 (parallel combination) and the rear bearings 60 and 60 (parallel combination) are arranged to cooperate with each other to form a back combination.

  Outer rings 51, 51 of the front bearings 50, 50 are fitted into the outer cylinder 13, and the outer ring spacer 54 is interposed by the front bearing outer ring presser 12 fastened and fixed to the axial end surface of the outer cylinder 13 with bolts 15. It is positioned and fixed in the axial direction with respect to the outer cylinder 13.

  Further, the inner rings 52, 52 of the front bearings 50, 50 are externally fitted to the rotary shaft 11, and the nuts 16 fastened to the rotary shaft 11 are connected to the rotary shaft 11 via the flinger 40 and the inner ring spacer 55. Positioned and fixed in the direction.

  The flinger 40 is externally fitted to the rotary shaft 11 on the tool side (left side in the figure) with respect to the front bearings 50, 50, and is fixed to the rotary shaft 11 together with the inner rings 52, 52 by a nut 16.

  The outer rings 61 and 61 of the rear bearings 60 and 60 are fitted into a sleeve 18 that is slidably fitted in the rear housing 14 so as to be slidable in the axial direction. The fixed rear bearing outer ring presser 19 is positioned and fixed in the axial direction with respect to the sleeve 18 via the outer ring spacer 64.

  Inner rings 62 and 62 of the rear bearings 60 and 60 are externally fitted to the rotary shaft 11, and are axially directed to the rotary shaft 11 via the inner ring spacer 65 by another nut 21 fastened to the rotary shaft 11. It is fixed to the position. A coil spring 23 is disposed between the rear housing 14 and the rear bearing outer ring retainer 19, and the spring force of the coil spring 23 presses the rear bearing outer ring retainer 19 together with the sleeve 18 backward. Thereby, a preload is applied to the rear bearings 60 and 60.

  On the tool side of the rotary shaft 11, a tool mounting hole 24 and a female screw 25 formed in the axial direction through the center of the shaft are provided. The tool attachment hole 24 and the female screw 25 are used for attaching a tool (not shown) such as a cutting tool to the rotary shaft 11. Instead of the tool mounting hole 24 and the female screw 25, a conventionally known draw bar (not shown) may be slidably inserted into the shaft core of the rotary shaft 11. Each draw bar has a collet portion for fixing a tool holder (not shown), and is biased in the counter tool side direction by the force of a disc spring.

  A rotor 26 disposed so as to be able to rotate integrally with the rotation shaft 11 and a stator 27 disposed around the rotor 26 are disposed substantially at the center in the axial direction between the front bearings 50, 50 and the rear bearings 60, 60 of the rotation shaft 11. With. The stator 27 is fixed to the outer cylinder 13 by fitting the cooling jacket 28 shrink-fitted into the stator 27 into the outer cylinder 13 constituting the housing H. The rotor 26 and the stator 27 constitute a motor M, and by supplying electric power to the stator 27, a rotational force is generated in the rotor 26 to rotate the rotating shaft 11.

  The flinger 40 has a boss portion 41 that fits around the rotary shaft 11 and a disc portion 42 that extends radially outward from the boss portion 41. The outer peripheral part 42 a of the disk part 42 constitutes the tip part of the flinger 40 and is located radially inward of the front bearing outer ring retainer 12.

  The flinger 40 is disposed so as to face the front bearing outer ring retainer 12 through a slight axial gap and radial gap, and constitutes a so-called labyrinth seal. That is, the axial inner end surface 42b of the disk portion 42 is opposed to the axial end surface 12a of the front bearing outer ring retainer 12 including the outer peripheral portion 42a through a slight gap, for example, a gap of about 0.5 mm. ing.

  As a result, an air curtain is formed between the axial end surface 42b of the outer peripheral portion 42a of the disk portion 42 and the axial end surface 12a of the front bearing outer ring retainer 12 due to the difference in peripheral speed, and the workpiece is processed. In doing so, a waterproof mechanism is configured to prevent the machining fluid falling on the spindle device 10 from entering the front bearings 50 and 50. Further, even if the machining fluid or dust enters the labyrinth region, it can be discharged to the outside from the outer peripheral portion 42a of the disk portion 42 by the swinging effect by the centrifugal force of the flinger 40, so that the machining fluid and dust enter the main shaft. Can be prevented.

  The flinger 40 is made of a carbon fiber composite material (CFRP) that has a higher tensile strength and a lower specific gravity than a metal.

  Specifically, as the carbon fiber composite material, for example, a woven fabric (sheet-like shape) made of PAN (polyacrylonitrile) as a main raw material, in which yarns made of carbon fibers are arranged in parallel, or made of yarns made of carbon fibers. ), A plurality of sheets impregnated with a thermosetting resin such as an epoxy resin containing a curing agent are superposed on each other, wound around a core metal, etc., and heated and cured. Moreover, the carbon fiber which used pitch system as the main raw material can also be used. By optimizing the fiber direction and angle, the carbon fiber composite material can optimize physical properties such as tensile strength, tensile elastic modulus, and linear expansion coefficient according to the application.

As the characteristics of the carbon fiber composite material, for example, carbon fiber mainly composed of PAN having a tensile strength of 1800 to 3500 MPa, a tensile elastic modulus of 130 to 280 GPa, and a specific gravity of 1.5 to 2.0 g / cc is used. When used, the tensile strength is equal to or higher than that of conventional high-strength steel and the like, and the specific gravity is about 1/5 (the specific strength is about three times that of a normal metal material). In addition, the coefficient of thermal expansion is -5 to + 12 × 10 ⁻⁶ by optimizing the fiber direction and angle.
Since it can be set to K- ¹ , it can be set to about 1 to 1/10 as compared with the conventional carbon steel.

  In this way, by using a carbon fiber composite material having a specific gravity smaller than that of metal, if the diameter is the same, the centrifugal force acting on the flinger 40 can be greatly reduced, and the flinger 40 at the time of high-speed rotation can be reduced. The possibility of centrifugal force damage is eliminated. Furthermore, since the tensile strength is equal to or higher than that of metal, deformation due to centrifugal force can be suppressed. Therefore, the restriction on the rotational speed of the rotating shaft 11 and the restriction on the size (radial direction) of the flinger 40 can be greatly relaxed.

  This makes it possible to increase the rotation speed of the flinger 40, which has been difficult to achieve in the past, or to increase the size of the flinger 40. It can be swung away to prevent intrusion into the bearing.

  The flinger 40 and the rotating shaft 11 are preferably fitted with a clearance fit of, for example, several μm in consideration of the difference in linear expansion coefficient between the metal and the carbon fiber composite material. Due to the expansion of the shaft 11, a tight fit is achieved. Further, the clearance between the flinger 40 and the front bearing outer ring retainer 12 also takes into account the difference in linear expansion coefficient between them, and interference occurs even if the metal rotary shaft 11 and the front bearing outer ring retainer 12 are thermally expanded. It is set to a gap that is not large (for example, φ0.5 mm or less).

  As described above, according to the spindle device 10 of the present embodiment, it is fixed to the rotary shaft 11 so as to be integrally rotatable, and constitutes a part of the waterproof mechanism that suppresses the intrusion of the machining liquid into the front bearings 50 and 50. Since at least a part of the flinger 40 is made of a carbon fiber composite material, the mass is smaller than that of metal, and the centrifugal force is small at the same rotational speed, so the influence of the centrifugal force on the flinger 40 is reduced. can do. Furthermore, since the tensile strength is higher than that of metal, deformation due to centrifugal force is further suppressed. As a result, the rotating shaft 11 can be rotated at a high speed, that is, with a dmn value of 1 million or more, more preferably with a dmn value of 1.5 million or more, and the size restriction on the flinger 40 is greatly relaxed and the radial length is reduced. Therefore, good waterproof performance can be obtained by ensuring a long labyrinth.

  Further, since the flinger 40 is disposed to face the front bearing outer ring presser 12 constituting the housing H via a slight gap, the flinger 40 and the front bearing outer ring presser 12 constitute a labyrinth seal that is a non-contact seal. It is possible to suppress the penetration of the machining fluid into the front bearings 50 and 50 stably over a long period of time. Further, the lighter flinger 40 reduces the inertia in the rotational direction, shortens the acceleration / deceleration time, shortens the cycle time, and can be expected to improve production efficiency. Furthermore, the mass of the tip of the rotating shaft 11 is reduced, the eigenvalue of the rotating shaft 11 can be increased, the rotation is possible at higher speed, and the vibration during high-speed rotation can also be reduced.

  The flinger 40 includes a boss portion 41 fitted on the rotary shaft 11 and a disc portion 42 extending radially outward from the boss portion 41, and an outer peripheral portion 42 a of the disc portion 42 is a flinger. The outer peripheral portion 42a of the disc portion 42 is opposed to the axial end surface 12a of the front bearing outer ring retainer 12 in the axial direction through a slight gap. As a result, even if the machining fluid or dust enters the labyrinth region, the machining fluid or dust can be discharged from the outer peripheral portion 42a of the disk portion 42 to the outside by the effect of swinging off due to the centrifugal force of the flinger 40. It is possible to prevent the processing liquid and dust from entering. Further, for example, by using the tool as a vertical spindle device that processes the tool downward, the machining fluid that has entered the labyrinth portion can be discharged from the outer peripheral portion 42a of the disk portion 42 when the machining is stopped, and the machining fluid is labyrinth. It can prevent staying in a part.

2A and 2B are partial cross-sectional views of a spindle device according to a modification of the present embodiment. In the flinger 40 shown in FIG. 2A, a convex portion 44 that protrudes toward the front bearing outer ring retainer 12 side is formed on the surface facing the front bearing outer ring retainer 12 in the middle of the disk portion 42 in the radial direction. Yes. Further, the front bearing outer ring retainer 12 is formed with a concave portion 12b on the surface facing the flinger 40 so as to face the convex portion 44 of the flinger 40 and accommodate the convex portion 44 through a slight gap. Therefore, the labyrinth portion can be formed long by the convex portion 44 of the flinger 40, and the waterproof performance can be improved.
Also in this modified example, the outer peripheral part 42a of the disk part 42 constituting the tip part of the flinger 40 is opposed to the axial end face 12a of the front bearing outer ring retainer 12 in the axial direction with a slight gap therebetween. By using it as a vertical spindle device, the machining fluid that has entered the labyrinth portion can be discharged from the outer peripheral portion 42a of the disk portion 42 when stopped, and it is possible to prevent the machining fluid from staying in the labyrinth portion. .

  Further, in the flinger 40 shown in FIG. 2 (b), the axially inner end surface 42b of the disk portions 42 and the axially end surface 12a of the front bearing outer ring retainer 12 that are opposed to each other gradually increase in the axial direction. It may be formed in a taper shape inclined to the tool side. By applying such a flinger 40 to the vertical spindle device, the machining fluid that has entered the labyrinth portion can be more efficiently discharged from the outer peripheral portion 42a of the disk portion 42 when stopped, and the machining fluid is discharged to the labyrinth portion. It can prevent more reliably that it stays.

(Second Embodiment)
Next, a second embodiment of the spindle device will be described with reference to FIG. The same parts as those in the spindle device of the first embodiment are denoted by the same or corresponding reference numerals, and description thereof will be simplified or omitted.

  As in the first embodiment, the housing H is externally fitted to the outer ring 51 of the front bearing 50, and is fixed to the axial end surface of the outer cylinder 13, and the front bearing outer ring presser that positions the outer ring 51 in the axial direction. 12 and so on. The front bearing outer ring retainer 12 is provided with a step portion 12c between the axially outer end surface and the outer peripheral surface.

  The flinger 40 includes a boss portion 41 fitted on the rotary shaft 11, a disk portion 42 extending radially outward from the boss portion 41, and a rear side (front bearing outer ring retainer 12 side) from the outer peripheral portion of the disk portion 42. ) And an annular portion 43 extending in a ring shape.

The annular portion 43 faces the outer peripheral surface of the stepped portion 12c in the radial direction through a slight gap, for example, a gap of 0.5 mm or less. Therefore, in this embodiment, compared to the first embodiment, a radial labyrinth portion is added between the inner peripheral surface of the annular portion 43 and the outer peripheral surface of the stepped portion 12c, and waterproof performance is improved. Can be improved.
Further, since the outer peripheral surface of the annular portion 43 of the flinger 40 is disposed radially inward from the outer peripheral surface of the housing H, for example, in a turning type spindle device, the housing H first interferes with an obstacle during turning. By doing so, damage to the flinger 40 can be suppressed.

  Since the flinger 40 is formed of a carbon fiber composite material, the centrifugal force acting on the annular portion 43 of the flinger 40 is reduced, and the opening side of the annular portion 43 that has a relatively weak strength cantilever structure (in the drawing) The right side) can be prevented from expanding radially outward.

  Thereby, according to the spindle apparatus 10 of this embodiment, in addition to the effect of 1st Embodiment by which the flinger 40 is formed from a carbon fiber composite material, the ring part 43 of the flinger 40 is the level | step difference of the outer ring | wheel holding | suppressing 12. By facing the outer peripheral surface of the portion 12c in the radial direction with a slight gap, a radial labyrinth portion can be added, and the waterproof performance can be improved.

  It should be noted that the flinger 40 having the annular portion 43 as in the present embodiment is applied to a spindle device that uses a tool with the tool oriented above the horizontal as well as a horizontal spindle device that uses the tool with the tool oriented horizontally. preferable.

(Third embodiment)
Next, a third embodiment of the spindle device will be described with reference to FIG. The same parts as those in the spindle devices of the first and second embodiments are denoted by the same or corresponding reference numerals, and description thereof will be simplified or omitted.

  The housing H of the present embodiment is screwed and fixed to the outer cylinder 13 fitted on the outer ring 51 of the front bearing 50 and the screw hole 13a formed in the inner peripheral surface of the outer cylinder 13, and the outer ring 51 is axially moved. And a front bearing outer ring retainer 31 for positioning. Accordingly, the coupling surface 32 between the outer cylinder 13 and the front bearing outer ring retainer 31 is formed facing the axial end surface of the housing H. A step portion 13 b is provided between the axial end surface of the outer cylinder 13 and the outer peripheral surface.

  The flinger 40 includes a boss portion 41 fitted on the rotary shaft 11, a disk portion 42 extending radially outward from the boss portion 41, and a rear side (front bearing outer ring retainer 31 side) from the outer peripheral portion of the disk portion 42. ) And an annular portion 43 extending in a ring shape. The annular portion 43 faces the outer peripheral surface of the stepped portion 13b in the radial direction through a slight gap, for example, a gap of 0.5 mm or less.

  Further, the disk portion 42 of the flinger 40 faces the coupling surface 32 between the outer cylinder 13 and the front bearing outer ring retainer 31 in the axial direction with a slight gap.

  Thereby, according to the spindle apparatus 10 of this embodiment, in addition to the effect of 1st Embodiment by the flinger 40 being formed from a carbon fiber composite material, the disk part 42 of the flinger 40 is the outer cylinder 13 and the front bearing. By facing the coupling surface 32 with the outer ring presser 31 via a slight axial gap, the coupling surface 32 is positioned inside the labyrinth, and entry of the machining fluid from the coupling surface 32 can be suppressed.

(Fourth embodiment)
Next, a fourth embodiment of the spindle device will be described with reference to FIG. The same parts as those of the spindle device of the first to third embodiments are denoted by the same or corresponding reference numerals, and description thereof will be simplified or omitted.

  The housing H includes an outer cylinder 13 that is externally fitted to the outer ring 51 of the front bearing 50, and a front bearing outer ring presser 12 that is fixed to the axial end surface of the outer cylinder 13 and positions the outer ring 51 in the axial direction. Therefore, the coupling surface 33 between the outer cylinder 13 and the front bearing outer ring retainer 12 is formed facing the outer peripheral surface of the housing H. The outer cylinder 13 is provided with a step portion 13b between the outer end surface in the axial direction and the outer peripheral surface, and the front bearing outer ring retainer 12 is designed to have substantially the same outer diameter as the outer peripheral surface of the step portion 13b. .

  The flinger 40 includes a boss portion 41 fitted on the rotary shaft 11, a disk portion 42 extending radially outward from the boss portion 41, and a rear side (front bearing outer ring retainer 12 side) from the outer peripheral portion of the disk portion 42. ) And an annular portion 43 extending in a ring shape. The annular portion 43 faces the outer peripheral surface of the front bearing outer ring retainer 12 and the outer peripheral surface of the stepped portion 13b in a radial direction through a slight gap, for example, a gap of 0.5 mm or less.

  Further, the annular portion 43 of the flinger 40 faces the coupling surface 33 between the outer cylinder 13 and the front bearing outer ring retainer 12 in the radial direction with a slight gap therebetween.

  Thereby, according to the spindle apparatus 10 of this embodiment, in addition to the effect of 1st Embodiment by which the flinger 40 is formed from a carbon fiber composite material, the flinger 40 includes the outer cylinder 13 and the front bearing outer ring presser 12. By facing the coupling surface 33 with a slight radial gap, the coupling surface 33 is positioned inside the labyrinth, and the penetration of the machining liquid from the coupling surface 33 can be suppressed.

(Fifth embodiment)
Next, a fifth embodiment of the spindle device will be described with reference to FIG. The same parts as those in the first to fourth embodiments are denoted by the same or corresponding reference numerals, and the description thereof will be simplified or omitted.

  The housing H includes an outer cylinder 13 that is externally fitted to the outer ring 51 of the front bearing 50, and a front bearing outer ring presser 12 that is fixed to the axial end surface of the outer cylinder 13 and positions the outer ring 51 in the axial direction.

  The flinger 40 includes a boss portion 41 fitted on the rotary shaft 11, a disk portion 42 extending radially outward from the boss portion 41, and a rear side (front bearing outer ring retainer 12 side) from the outer peripheral portion of the disk portion 42. ) And an annular portion 43 extending in a ring shape. The annular portion 43 has a length that exceeds the axially inner end surface 50a of the front bearing 50, and has a slight gap between the outer peripheral surface of the front bearing outer ring retainer 12 and the outer peripheral surface of the outer cylinder 13, for example, a gap of 0.5 mm or less. Opposite to each other in the radial direction.

  Thereby, according to the spindle apparatus 10 of this embodiment, in addition to the effect of 1st Embodiment by which the flinger 40 is formed from a carbon fiber composite material, the ring part 43 of the flinger 40 is the axis | shaft of the front side bearing 50. It has a length that exceeds the inner end surface 50a in the direction, and faces the outer peripheral surface of the housing H in the radial direction with a slight gap, thereby preventing the processing liquid from being applied to the housing H and excessively cooling the housing H. Thus, the temperature difference between the inner and outer rings 51 and 52 of the front bearing 50 can be reduced, and for example, an increase in preload in the front bearing 50 to which a fixed position preload is applied can be suppressed.

In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.
Further, although the motor built-in type spindle device has been described, the present invention is not limited to this, and the present invention can be similarly applied to a belt drive type spindle device and a motor direct connection drive type spindle device coupled to a rotation shaft of a motor. Further, the present invention is not limited to a spindle device for machine tools, and can be applied to a spindle device of other high-speed rotating equipment that requires a waterproof function.
The spindle device of the present invention may be applied as a vertical spindle device or a horizontal spindle device, or may be a swivel spindle device.

  In the present embodiment, the flinger is entirely formed of a carbon fiber composite material, but at least a part of the flinger may be formed of a carbon fiber composite material. For example, the flinger is composed of two members divided in the radial direction at the disk portion, the inner diameter side portion is formed of a metal material such as SC material, SCM material, SUS material, AL material, CU material, and the outer diameter side portion. You may form with a carbon fiber composite material. Thereby, while suppressing a centrifugal force in the outer-diameter side part where centrifugal force becomes the largest, expansion | swelling of an inner diameter side part can be suppressed with a carbon fiber composite material with high mechanical strength. In addition, since the boss portion formed of a metal material is made of the same metal as the rotating shaft 11, the nut 16, the inner rings 52, 52, and the inner ring spacer 55, there is little difference in elongation due to the difference in linear expansion coefficient, The axial fixing force of the inner rings 52, 52 is difficult to change.

  Further, the shape of the flinger 40 can be arbitrarily designed as long as the waterproof performance of each embodiment is satisfied. For example, the axial end surface (the axial outer end surface or the axial inner end surface), the outer peripheral surface, or the circle of the disk portion 42 can be used. The outer peripheral surface, inner peripheral surface, and axial inner end surface of the ring portion 43 may be formed in a tapered shape.

10 Spindle device 11 Rotating shaft 12 Outer ring retainer 40 Flinger 41 Boss part 42 Disc part 43 Ring part 44 Convex part 50 Front bearing (bearing)
60 Rear bearing H Housing

Claims (1)

A housing having an outer cylinder fitted over the outer ring of the bearing, and an outer ring presser fixed to the axial end surface of the outer cylinder and positioning the outer ring in the axial direction;
A rotating shaft supported by the housing via the bearing so as to be relatively rotatable;
A spindle device including a flinger that is fixed to the periphery of the rotary shaft so as to be integrally rotatable and forms a labyrinth seal with the outer ring presser,
The flinger includes a boss part fitted on the rotating shaft and a disk part extending radially outward from the boss part, and an outer peripheral part of the disk part constitutes a tip part of the flinger. And
The outer peripheral portion of the disk portion is opposed to the axial end surface of the outer ring retainer in the axial direction through a slight gap,
In the middle of the disk portion in the radial direction, a convex portion that protrudes toward the outer ring pressing side is formed on the surface facing the outer ring pressing,
At least a part of the flinger is formed of a carbon fiber composite material.

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