JP4811657B2 - Spindle device - Google Patents

Description

  The present invention relates to a spindle device for use in a motor, a machine tool, a medical device, and the like, and more particularly, to a spindle device in which a motor function using fluid energy and a hydrostatic bearing function are integrated.

Many spindle devices of general machine tools are supported by rolling bearings, and transmit the rotational motion of an electric drive motor provided separately from the spindle device via a transmission element such as a belt or a pulley. When the spindle device having such a configuration is used in a precise machine tool system, the following problems occur.
First, it is difficult not only to realize high-precision rotational movement due to friction and mechanical play in the rolling bearing, but also to cause seizure of the rolling bearing during high-speed rotation required in ultra-precision machining. Therefore, it is necessary to adopt a system in which the spindle is supported by the hydrostatic bearing.
Second, when the spindle rotates at high speed, vibrations generated by transmission elements such as belts and pulleys are transmitted to the spindle, causing the spindle itself to vibrate, so either install a built-in motor or install a turbine on the spindle itself. It is necessary to adopt a system that does not require a mechanical transmission element such as a belt by a method of spraying fluid.
Third, when the spindle is used in a machine tool, frictional heat generated between the tool and the work material during machining is transferred to the spindle, causing thermal expansion of the spindle, which causes machining errors, so that the spindle device Need to be cooled.
As a spindle device for dealing with these problems, the present inventor has previously proposed a motor-integrated spindle device disclosed in Patent Document 1.
JP 2003-191142 A

As described above, the spindle device used in a machine tool that performs high-precision machining has a stable and high-precision support function using a hydrostatic bearing, a motor function that generates rotational movement of the spindle by fluid energy, and a cooling function. It will be necessary.
The spindle device in Patent Document 1 has a motor function and a cooling function for causing the spindle to rotate by the energy of fluid, and solves these problems. However, this spindle device can only perform a unique rotation determined by the spindle structure. In addition, it is difficult to manufacture a fluid outflow port in the spindle device.

  The present invention has been made in view of the above points, and by supporting and rotating with a fluid and cooling, the spindle has a high-precision support function, a motor function and a cooling function, and easily manufactures the outflow port of the spindle. Another object of the present invention is to provide a spindle device that can be easily changed and adjusted.

The spindle device of the present invention according to claim 1 is a fluid flow path formed so as to extend in an axial direction inside a center, an inflow port communicating with the fluid flow path and allowing fluid to flow into the fluid flow path, and the fluid The spindle is supported by a spindle having an outflow port that communicates with the flow path and allows the fluid to flow out of the fluid flow path, and the pressure of the fluid that flows out of the fluid flow path or the pressure of the fluid supplied from the outside of the spindle. A plug component having a thrust hydrostatic bearing and a journal hydrostatic bearing, wherein the outflow port has a perforation communicating with the outer periphery of the spindle from the fluid flow path, and a curved passage fixed in the perforation; is formed by the plug part, has a first passage extending in an axial direction and a second passage extending substantially perpendicular to said first passage, said curved shape Road is formed, said plug part, said second passage is characterized by being configured to be fixed within the borehole so as to face in any direction.
According to a second aspect of the present invention, in the spindle device according to the first aspect, the bent shape of the plug part is a shape whose angular momentum changes when a fluid flows.
According to a third aspect of the invention, in the spindle device according to claim 1, said plug part, characterized by being fixed by screwing or fit within the borehole.
According to a fourth aspect of the present invention, in the spindle device according to the first aspect, a plurality of the perforations are provided, and the plug component is fixed to each of the perforations.
According to a fifth aspect of the present invention, there is provided the spindle device according to the present invention, wherein the first fluid flow path and the second fluid flow path formed so as to extend in the axial direction inside the center and separated from each other at the intermediate portion; A first inflow port and a second inflow port independently communicating with each of the channel and the second fluid flow path, and independently communicating with each of the first fluid flow path and the second fluid flow path. A spindle having a first outlet port and a second outlet port, and a thrust hydrostatic bearing and a journal hydrostatic bearing that support the spindle with a pressure of pressurized fluid, the first outlet port and Each of the second outflow ports includes a perforation communicating with the outer periphery of the spindle from each of the first fluid flow path and the second fluid flow path, and a curved passage fixed in the perforation. Plug part with Is formed by the said plug part, it has a first passage extending in an axial direction and a second passage extending substantially at right angles to the first passage, and a passage of said curved shape, The plug part may be configured to be fixed in the perforation so that the second passage is directed in an arbitrary direction .

According to the present invention, by rotating the spindle with the energy of the fluid and stabilizing it with a hydrostatic bearing, it has a high-precision support function, a motor function and a cooling function, and can easily manufacture the outflow port of the spindle. Can do.
In addition, the rotational performance of the spindle can be easily changed and adjusted by changing the insertion angle of the plug part having a curved passage inserted into the perforation communicating with the outer periphery of the spindle.

The spindle device according to the first embodiment of the present invention includes a fluid channel formed in the center so as to extend in the axial direction, an inflow port communicating with the fluid channel and allowing fluid to flow into the fluid channel, A spindle having an outflow port that communicates with the flow path and allows the fluid to flow out of the fluid flow path; and a thrust static that supports the spindle with the pressure of the fluid that flows out of the fluid flow path or the pressure of the fluid supplied from outside the spindle. ; and a pressure bearing and journal hydrostatic bearing, the outlet port is formed by a plug part having a perforated communicating from the fluid flow path to the outer periphery of the spindle, a passage of a fixed curved shape in the borehole, the plug component Has a first passage extending in the axial direction and a second passage extending substantially perpendicular to the first passage to form a curved passage, and the plug part is connected to the second passage. There is obtained a configuration which can be fixed in the borehole so as to face in any direction. According to the present embodiment, the spindle can be provided with a high-precision support function, a motor function, and a cooling function by fluid energy, and by fixing a plug component having a curved passage in the perforation, The outflow port of the spindle can be easily manufactured. The rotational performance of the spindle can be easily changed and adjusted by changing the insertion angle of the plug part having a curved passage fixed in the perforation communicating with the outer periphery of the spindle. In addition, a plug component having a curved passage can be manufactured with a simple configuration and method. Further, since the plug component can be fixed by changing the fixing angle, that is, the direction of the second passage, the outflow direction of the fluid flowing out from the outflow port can be set to an arbitrary direction. As a result, the rotational direction, rotational speed and rotational angle of the spindle, and further the amount of displacement in the thrust direction can be controlled arbitrarily.
In the spindle device according to the first embodiment, the second embodiment of the present invention is such that the bent shape of the plug component is a shape in which the angular momentum changes when a fluid flows. According to the present embodiment, the spindle can be rotated in a direction corresponding to the bent shape of the plug component by flowing a fluid through the outflow port.
According to a third embodiment of the present invention, in the spindle device according to the first embodiment, a plug component is fixed in a bore by screwing or fitting. According to the present embodiment, it is possible to easily and reliably fix the direction in which the fluid flows out from the plug component, that is, the direction of the second passage in an arbitrary direction.
In the fourth embodiment of the present invention, the spindle device according to the first embodiment has a configuration in which a plurality of perforations are provided and a plug component is fixed to each of the perforations. According to the present embodiment, the rotation direction, rotation speed, and rotation angle of the spindle can be precisely and easily controlled.
A spindle device according to a fifth embodiment of the present invention includes a first fluid channel and a second fluid channel formed so as to extend in an axial direction inside a center and separated from each other at an intermediate portion, and a first fluid A first inflow port and a second inflow port independently communicating with each of the flow path and the second fluid flow path, and a first inflow independently communicating with each of the first fluid flow path and the second fluid flow path. A spindle having one outflow port and a second outflow port, and a thrust hydrostatic bearing and a journal hydrostatic bearing that support the spindle with the pressure of pressurized fluid, the first outflow port and the second outflow port each port is formed with perforations communicating from each of the first fluid flow path and the second fluid flow path to the outer periphery of the spindle, by a plug part having a passage that fixed bending shape within the borehole, the plug Parts are axes A first passage extending in a direction and a second passage extending substantially at right angles to the first passage to form a curved passage, and the plug portion can be disposed in any direction. It is configured to be fixed in the perforation so as to face . According to the present embodiment, the outflow port for rotating the spindle can be easily manufactured. In addition, it is possible to obtain a spindle device that can be rotated in both forward and reverse rotation directions and that can precisely control the rotation speed and the rotation angle. In addition, a plug component having a curved passage can be manufactured with a simple configuration and method. Further, since the plug component can be fixed by changing the fixing angle, that is, the direction of the second passage, the outflow direction of the fluid flowing out from the outflow port can be set to an arbitrary direction. As a result, the rotational direction, rotational speed and rotational angle of the spindle, and further the amount of displacement in the thrust direction can be controlled arbitrarily.

Hereinafter, a spindle apparatus according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing a configuration of a spindle device in Embodiment 1 of the present invention.
In the spindle device in the present embodiment, a spindle 2 in which a motor unit 1 is incorporated, a journal hydrostatic bearing 3 and a thrust hydrostatic bearing 4 are supported by a casing 5. A hole extending in the axial direction is formed in the spindle 2 in the center of the spindle 2 to form a fluid channel 21, and an end of the fluid channel 21 is plugged with a plug 27.
The motor unit 1 includes an inflow port 6 through which a fluid such as water supplied from an external pump or a compressor (not shown) flows into the fluid flow path 21 of the spindle 2, and a fluid within the fluid flow path 21 of the spindle 2. Outflow port 7 for flowing out from the outside.
A pair of outflow ports 7 are provided on both sides of the inflow port 6, and the path of the fluid flowing in from the inflow port 6 is branched into two along the fluid flow path 21 extending in the axial direction in the spindle 2. Out of port 7.

An example of the outflow port 7 is shown in FIG. FIG. 2 is a cross-sectional view of the spindle 2 in FIG.
The spindle 2 is formed with a plurality of (three in FIG. 2A) perforations 22, 23, and 24 communicating with the outer periphery of the spindle 2 from a fluid flow path 21 formed in the center thereof.
These perforations 22, 23, and 24 are formed by drilling in the radial direction from the outer periphery of the spindle 2 toward the center so as not to penetrate the opposite side of the spindle 2. The perforations 22, 23, and 24 do not necessarily have to be plural, and may be formed at one place. However, in order to increase the rotational speed of the spindle 2, it is preferable to provide plural places. A plug component 25 shown in FIG. 2B is inserted into each of the perforations 22, 23, 24 by fitting or screwing. The fixing of the plug part 25 by this fitting or screwing is a desirable method because it is easy and reliable to arbitrarily set the direction of the second passage 252.
Inside the plug part 25, there are a first passage 251 extending in the axial direction of the plug part 25 and a second passage 252 extending substantially at right angles to the first passage 251 at the tip of the first passage 251. The first passage 251 and the second passage 252 form a bent passage 26 in the plug part 25. Thereby, the plug component 25 having a bent shape can be manufactured with a simple configuration and method.
For example, the first passage 251 and the second passage 252 are created as follows. First, a through hole penetrating in the axial direction for forming the first passage 251 with respect to the plug part 25 is formed, and then, the side wall of the plug part 25 communicates with the through hole and is substantially perpendicular to the first through hole. A through-hole for forming the second passage 252 is formed. Finally, the plug 253 is inserted into the first passage 251 extending to the tip of the plug part 25 to seal the tip of the first passage 251. Thus, when manufacturing the plug component 25 having the curved passage 26, a manufacturing method in which a plug is inserted into one through-hole is a more practical method.
The angle and shape of the bent passage 26 to be bent need not be a right angle or a straight line as long as the angular momentum of the fluid changes when the fluid flows in the bent passage 26. For example, it may be along a smooth curve.

An example of the completed outflow port 7 is shown in FIG. 3 is a cross-sectional view showing the internal structure of the outflow port of the spindle device in FIG. 1, and FIG. 3 (a) shows the fluid flowing out of the outflow port 7 counterclockwise and clockwise with respect to the spindle 2. FIG. FIG. 3B shows an example in which a rotating torque is applied, and FIG. 3B is an example in which a fluid flows out from the outflow port 7 in the clockwise direction and torque that rotates counterclockwise with respect to the spindle 2 is applied.
Thus, the plurality of outflow ports 7 for rotating the spindle 2 can be easily manufactured by simply inserting the plug parts 25 into the perforations 22, 23, 24 formed in the spindle 2.
Further, the rotation direction of the spindle 2 can be arbitrarily set by the direction of the curved passage 26 of each plug part 25 inserted into the perforations 22, 23, 24 formed in the spindle 2.
In this way, when the direction of the curved passage 26 (the second passage 252) is made counterclockwise as shown in FIG. 3A, it rotates clockwise as shown by an arrow A. If the direction of the curved passage 26 (the second passage 252) is clockwise as shown in FIG. 3B, it rotates counterclockwise as shown by an arrow B.

On the other hand, in FIG. 1, a thrust hydrostatic bearing 4 that supports the spindle 2 with the pressure of the fluid that flows out from the fluid flow path 21 is formed outside the outflow port 7 in the spindle axial direction. The thrust hydrostatic bearing 4 is configured by extending a part of the side wall of the spindle 2 in the radial direction, and forming a recess in the extension, and a through hole having a smaller diameter than the recess in communication with the recess. The spindle 2 is supported in the thrust direction while controlling the axial position of the spindle 2 by controlling the amount of fluid such as water supplied to the thrust hydrostatic bearing 4.
Further, a journal hydrostatic bearing 3 that supports the spindle 2 with the pressure of the fluid that flows out from the fluid flow path 21 is formed further outside in the spindle axial direction of the outflow port 7. The journal hydrostatic bearing 3 is formed by forming a recess from the side wall of the spindle 2 and a through hole having a smaller diameter than the recess in communication with the recess. Then, by controlling the amount of fluid such as water supplied to the journal hydrostatic bearing 3, the spindle 2 is supported in the journal direction while controlling the position of the spindle 2 in the journal direction.

Next, the operation will be described.
The fluid flowing in from the inflow port 6 is branched in two directions in the fluid flow path 21 in the center of the spindle 2, and further branched in two in the vicinity of the outflow port 7, and one of the fluids is a curved path. 26 flows out of the spindle 2. At this time, since the fluid bends and flows out from the first passage 251 to the second passage 252 in the curved passage 26, the angular momentum of the fluid changes, and accordingly, a torque for rotating the spindle 2 is generated. And function as a motor. This motor function can generate torque each time fluid flows out of the curved passage 26.
That is, the rotation speed and rotation angle of the spindle 2 can be adjusted by the number of the curved passages 26 and the fluid flow rate. Further, the rotation direction of the spindle 2, or the rotation speed and the rotation direction can be precisely adjusted by the direction of the second passage 252 of the curved passage 26. As described above, when a plurality of perforations are provided and a plug part is inserted and fixed in each perforation, the rotation direction, the number of rotations, and the rotation angle of the spindle can be precisely and easily controlled. Further, by flowing a fluid through the outflow port 7, the spindle 2 can be rotated in a direction corresponding to the bent shape of the plug part 25.
The other fluid branched near the outflow port 7 is further branched into two near the thrust hydrostatic bearing 4, and one is supplied to the thrust hydrostatic bearing 4 to support the spindle 2 in the thrust direction. It flows out of the spindle 2. The other is supplied to the journal hydrostatic bearing 3 to support the spindle 2 in the journal direction and to flow out of the spindle 2.

As described above, in the spindle device of this embodiment, the spindle 2 can be provided with a high-precision support function, a motor function, and a cooling function by the energy of the fluid, and the plug part 25 having the curved passage 26 is drilled. By fixing to 22, 23, 24, the outflow port 7 can be easily manufactured in the spindle 2. Further, the rotation speed and rotation direction of the spindle 2 can be easily changed and adjusted.
The fluid supplied to the spindle 2 is optimally water, but other fluids such as air and oil can be used. Further, since the fluid flows on the outer periphery and the inside of the spindle 2, the temperature change of the spindle 2 can be made constant by controlling the temperature of the fluid. Therefore, the thermal expansion of the spindle 2 can be minimized, and processing errors caused by the thermal expansion can be eliminated.

FIG. 4 is a cross-sectional view of the outflow port of the spindle device according to the second embodiment of the present invention.
The configuration of the spindle device of the present embodiment is the same as that of the first embodiment described with reference to FIG. 1 except that the configuration of the outflow port 7 of the spindle device in the first embodiment is different. Therefore, the configuration and operation of different parts will be described, and other descriptions will be omitted.
The outflow port 7 in the present embodiment is an example in which a fluid flows out from the outflow port 7 to give a rotating torque to the spindle 2 and a moving force in the thrust direction.
In this embodiment, four perforations 11, 12, 13, and 14 are formed at 90 degrees from each other through the fluid flow path 21 formed in the center of the spindle 2 to the outer periphery of the spindle 2. . In the two perforations 11, 13 in the four perforations 11, 12, 13, 14, the fluid outflow direction by the curved passage 26 of the plug part 25 is opposite to the outer peripheral direction of the spindle 2. Plug parts 25 are respectively inserted and fixed by fitting or screwing so as to face clockwise. Needless to say, the plug parts 25 may be installed in any number of places, not limited to four places.
In this configuration, the spindle 2 rotates clockwise as indicated by an arrow A in FIG. The number of rotations at this time is two at the plug parts 25 that give rotational torque to the spindle 2. Becomes smaller.

On the other hand, the other two perforations 12 and 14 in the diagonal direction are arranged so that the fluid outflow direction by the curved passage 29 of the plug part 28 is directed to the axial direction of the spindle 2, that is, in FIG. Plug parts 28 are inserted and fixed by fitting or screwing so as to face in the vertical direction of the side.
In this case, since the fluid outflow direction by the curved passage 29 of the plug part 28 is oriented in the vertical direction on the front side with respect to the paper surface, the displacement force in the thrust direction, that is, the axial direction is simultaneously applied to the spindle 2. Work and move a small distance to the back side of the page. This amount of movement can be controlled by the flow rate of the fluid from the curved passage 29. Further, it can be controlled by shifting the direction of the curved passage 29 from the axial direction of the spindle 2.
This movement of a minute distance is effective in the following cases. For example, when a workpiece is provided at the tip of the spindle 2 and the workpiece is processed by a tool from the outside, when the tool contacts the workpiece, the spindle 2 is pushed and slightly moves in the axial direction. Sometimes. The slight movement of the spindle 2 in the axial direction can be corrected by the movement of a minute distance by the displacement force.
As described above, in the spindle device of the present embodiment, the number of plug parts having a curved path and the direction of the second path of the curved path are arbitrarily set, and the plug part is fixed in the perforation. Thus, the rotational direction, rotational speed and rotational angle of the spindle 2 and further the displacement amount in the thrust direction can be arbitrarily controlled.

FIG. 5 is a cross-sectional view showing the configuration of the spindle device according to the third embodiment of the present invention. In FIG. 5, the same parts as those in FIG.
The spindle device according to the present embodiment has a configuration in which the fluid flow paths 31 and 32 of the spindle 2 in which the motor unit 1 is incorporated are divided into two at the intermediate portion and the two motor units 1 are provided. The spindle 2 is supported on the casing 5 by a pair of journal hydrostatic bearings 41 and 42 and a pair of thrust hydrostatic bearings 51 and 52.
That is, a pair of holes that are separated by the partition wall 40 and extend in the axial direction are formed in the center of the spindle 2 to form fluid flow paths 31 and 32, and flanges 30 and 39 are formed at both ends of the spindle 2. Is formed.
An inflow port 35 communicates with the fluid flow path 31 of the spindle 2 to allow a fluid such as water supplied from an external pump (not shown) to flow into the fluid flow path 31 of the spindle 2, and the fluid is supplied to the spindle 2. An outflow port 36 for flowing out from the fluid flow path 31 to the outside is formed.
The outflow port 36 is formed in communication with the fluid flow path 31 in the flange 39 formed outside the fluid flow path 31 with respect to the inflow port 35, that is, on the end side (left side in the drawing) of the spindle 2. ing.
The fluid flowing in from the inflow port 35 flows along the fluid flow path 31 extending in the axial direction in the spindle 2 and flows out from the outflow port 36.
The outflow port 36 is configured by inserting a plug part 25 having a curved passage 26 into a perforation 22 formed in the spindle 2 in the same manner as the outflow port 7 in the first embodiment. As shown in a), the fluid is made to flow counterclockwise to give a torque that rotates clockwise as indicated by an arrow A to the spindle 2.
In addition, since the diameter of the collar part 39 is large in a present Example, it is set as the structure which inserts and fixes the plug component 25 to the upper end of the step-shaped perforation 22. FIG. If it is this structure, the outflow port 36 can be easily manufactured in the large diameter collar part 39. FIG.

Similarly, an inflow port 37 that communicates with the fluid flow path 32 of the spindle 2 and allows a fluid such as water supplied from an external pump to flow into the fluid flow path 32 of the spindle 2, and the fluid flow of the spindle 2. An outflow port 38 is formed to flow out of the passage 32 to the outside. The outflow port 38 is formed in communication with the fluid flow path 32 in the flange 30 formed outside the fluid flow path 32 with respect to the inflow port 37, that is, on the end side (right side in the drawing) of the spindle 2. ing. The fluid flowing in from the inflow port 37 flows along the fluid flow path 32 extending in the axial direction in the spindle 2 and flows out from the outflow port 38.
The outflow port 38 is configured by inserting a plug part 25 having a curved passage 26 into a perforation 22 formed in the spindle 2 in the same manner as the outflow port 7 in the first embodiment. As shown in b), the fluid is made to flow clockwise, and a torque is applied to the spindle 2 to rotate counterclockwise as indicated by arrow B.

Thrust hydrostatic bearings 51 and 52 are formed at an intermediate position between the inflow port 35 and the outflow port 36 and at an intermediate position between the inflow port 37 and the outflow port 38, respectively. The thrust hydrostatic bearings 51 and 52 are supported in the thrust direction while controlling the axial position of the spindle 2 by controlling the amount of fluid such as water supplied from an external pump. The supplied fluid is discharged from the discharge ports 75 and 76.
Journal hydrostatic bearings 41 and 42 are further formed at an intermediate position between the inflow port 35 and the outflow port 36 and an intermediate position between the inflow port 37 and the outflow port 38. The journal hydrostatic bearings 41 and 42, similarly to the thrust hydrostatic bearings 51 and 52, control the position of the spindle 2 in the axial direction by controlling the amount of fluid such as water supplied from an external pump. Support in the journal direction. The supplied fluid is discharged from the discharge ports 75 and 76.
A rotary encoder 80 for detecting the rotation speed or rotation angle of the spindle 2 is provided at one end of the spindle 2, and the flow rate of the fluid from the pump is controlled according to the detected rotation speed or rotation angle. It is possible. A work holder 82 that holds a work piece 81 is provided at the other end of the spindle 2.

Next, the operation will be described.
When it is desired to rotate the spindle 2 in the clockwise direction, the fluid is supplied only to the inflow port 35 without supplying the fluid to the inflow port 37. The fluid supplied to the inflow port 35 flows along the fluid flow path 31 extending in the axial direction in the spindle 2 and flows out from the outflow port 36. The outflow port 36 causes the fluid to flow out counterclockwise as shown in FIG. 3A, and gives the spindle 2 a torque that rotates clockwise as indicated by the arrow A. It rotates in the clockwise direction at a rotational speed corresponding to the flow rate of the fluid being supplied.
When it is desired to reduce the rotational speed of the spindle 2, the flow rate of the fluid supplied to the inflow port 35 may be reduced by adjusting the fluid flow rate from the pump. Alternatively, the number of rotations of the spindle 2 can be reduced by supplying fluid from the pump to the inflow port 37.
That is, when a fluid is also supplied to the inflow port 37, the fluid supplied to the inflow port 37 flows along the fluid flow path 32 extending in the axial direction in the spindle 2 and flows out from the outflow port 38. The outflow port 38 causes the fluid to flow out clockwise as shown in FIG. 3B, and gives the spindle 2 a torque that rotates counterclockwise as indicated by an arrow B. Torque is generated to rotate counterclockwise at a rotational speed corresponding to the flow rate of the fluid supplied to. Therefore, the rotational speed of the spindle 2 rotating in the clockwise direction is reduced under the influence of the torque acting in the counterclockwise direction.
In order to stop the rotation of the spindle 2, the flow rate of the fluid supplied from the pump to the inflow port 35 is set to 0 (zero) or the flow rate of the fluid supplied to the inflow ports 35 and 37 is made the same. Good.
When the spindle 2 is to be rotated in the counterclockwise direction, the fluid is not supplied to the inflow port 35, but the fluid is supplied only to the inflow port 37, or the flow rate of the fluid supplied to the inflow port 35 is increased. The flow rate of the fluid supplied to the port 37 may be increased.

Thus, the spindle 2 tends to rotate in the opposite directions by the fluid supplied from the pump to each of the fluid flow paths 31 and 32. As a result, the spindle 2 rotates with the rotation direction and the number of rotations changed according to the difference in angular momentum obtained by the fluid supplied to each of the fluid flow paths 31 and 32.
For example, if the angular momentum generated on the fluid flow path 31 side is ω1, the angular momentum generated on the fluid flow path 32 side is ω2, and the absolute value | ω1 | of ω1 is greater than the absolute value | ω2 | The rotation of 2 rotates at a rotational speed determined by the magnitude of the difference of | ω1 | − | ω2 | and rotates in the direction of ω1.

The rotational direction and the rotational speed of the spindle 2 feed back the rotational direction and the rotational speed of the spindle 2 detected by the rotary encoder 80 to the pump, and supply the fluid flow rate to the fluid flow path 31 and the fluid flow path 32. By controlling the flow rate of the fluid, it is possible to control to a predetermined rotational direction and rotational speed.
Also, the rotation angle of the spindle 2 can be controlled. That is, the rotary encoder 80 detects the rotation angle of the spindle 2 and feeds it back to the controller to directly control the pump, or to control the flow rate of the fluid supplied to the spindle using various control valves such as a servo valve. Thus, when the flow rate of the fluid supplied to the fluid flow path 31 and the fluid flow path 32 is set to 0 (zero) when the predetermined rotation angle is reached, the spindle 2 stops rotating at the position at that time. When the rotation angle exceeds the target value, the spindle 2 can be controlled to a predetermined rotation angle position by flowing a fluid in the reverse rotation direction.

As described above, according to the spindle device of the present embodiment, the spindle 2 can be rotated in either the forward or reverse rotation direction, and the rotation angle and the number of rotations can be controlled. You can easily perform operations such as stopping with.
In the present embodiment, the spindle device is configured to pivotally support the spindle 2 with the pressure of the fluid supplied from the outside of the spindle 2, but from the fluid flow paths 31 and 32 inside the spindle 2 as in the first embodiment. The spindle 2 may be supported by the pressure of the fluid to be discharged. In other words, the thrust hydrostatic bearing and the journal hydrostatic bearing may be configured to support the spindle with the pressure of the pressurized fluid. And if it is the structure which supports a spindle with the pressure of the fluid which flows out out of the fluid flow path inside a spindle, the structure of the system | strain which supplies the fluid to a spindle will be simplified.

  The spindle device according to the present invention has effects such that the outflow port can be easily manufactured, and the rotational performance of the spindle can be easily changed and adjusted. As a motor, a machine tool, a medical device, etc. Useful.

Sectional drawing which shows the structure of the spindle apparatus in Example 1 of this invention. XX sectional view of the spindle device in FIG. Sectional drawing which shows the internal structure of the outflow port of the spindle apparatus in FIG. Sectional drawing of the outflow port of the spindle apparatus in Example 2 of this invention Sectional drawing which shows the structure of the spindle apparatus in Example 3 of this invention.

DESCRIPTION OF SYMBOLS 1 Motor part 2 Spindle 3 Journal hydrostatic bearing 4 Thrust hydrostatic bearing 5 Casing 6 Inflow port 7 Outflow port 11, 12, 13, 14 Perforation 21 Fluid flow path 22,23,24 Perforation 25,28 Plug part 26,29 Bending Shaped passage 27 Plug 30, 39 Gutter 31, 32 Fluid flow path 35, 37 Inflow port 36, 38 Outflow port 41, 42 Journal hydrostatic bearing 51, 52 Thrust hydrostatic bearing 40 Bulkhead 75, 76 Discharge port 80 Rotary encoder 81 Workpiece 82 Workholder 251 First passage 252 Second passage 253 Plug

Claims (5)

A fluid channel formed in the center so as to extend in the axial direction; an inflow port that communicates with the fluid channel; allows fluid to flow into the fluid channel; and communicates with the fluid channel from the fluid channel. A spindle having an outlet port for draining;
A thrust hydrostatic bearing and a journal hydrostatic bearing that support the spindle with the pressure of the fluid flowing out of the fluid flow path or the pressure of the fluid supplied from the outside of the spindle,
The outflow port is formed by a perforation communicating from the fluid flow path to the outer periphery of the spindle, and a plug part having a curved passage fixed in the perforation ,
The plug part has a first passage extending in an axial direction and a second passage extending substantially perpendicular to the first passage, and forms the curved passage.
A spindle apparatus characterized in that the plug part can be fixed in the perforation so that the second passage is oriented in an arbitrary direction .   2. The spindle device according to claim 1, wherein the bent shape of the plug part is a shape in which an angular momentum changes when a fluid flows. 3. The spindle device according to claim 1 , wherein the plug part is fixed in the perforation by screwing or fitting.   The spindle device according to claim 1, wherein a plurality of the perforations are provided, and the plug component is fixed to each of the perforations. In each of the first fluid channel and the second fluid channel formed in the center so as to extend in the axial direction and separated from each other in the middle portion, the first fluid channel and the second fluid channel A first inflow port and a second outflow port which are independently communicated with each other, and a first outflow port and a second outflow port which are independently communicated with each of the first fluid channel and the second fluid channel. A spindle having
A thrust hydrostatic bearing and a journal hydrostatic bearing that support the spindle with the pressure of a pressurized fluid;
Each of the first outflow port and the second outflow port is a perforation communicating with the outer periphery of the spindle from each of the first fluid flow path and the second fluid flow path, and is fixed in the perforation. Formed by a plug part having a bent-shaped passage ,
The plug part has a first passage extending in an axial direction and a second passage extending substantially perpendicular to the first passage, and forms the curved passage.
A spindle apparatus characterized in that the plug part can be fixed in the perforation so that the second passage is oriented in an arbitrary direction .

Images