JPH09317769A - Main spindle device and method for adjusting balance of main spindle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain a precise adjustment against a minute unbalanced amount of a main spindle even in the case that the main spindle is rotated at a high speed. SOLUTION: The device is provided with a main spindle 10; a static pressure air bearing 3 and a static pressure oil bearing 4 for supporting the main spindle 10 in a radial direction; a displacement meter 7 for measuring a displacement of the main spindle 10; a rotation sensor 8 for detecting a rotating pulse of the main spindle 10; and a calculating section 9 for calculating an unbalanced amount and an angle of the main spindle 10 in response to a displacement of the main spindle 10 attained from the displacement meter 7 and a rotating pulse attained from the rotation sensor 8.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention according to claims 1 to 11 of the present invention relates to a spindle device used as, for example, a polishing apparatus, and the invention according to claims 12 to 15 of the present invention is the above spindle device. The present invention relates to a spindle balance adjusting method used to adjust the balance of the spindle.

[0002]

2. Description of the Related Art Conventionally, as the above spindle device, for example, there is a polishing device shown in FIG.

As shown in FIG. 7, this polishing apparatus 101
Is a housing 102 and a grindstone T1 housed in the housing 102 and having one end (the end on the right side in the drawing) connected to a drive unit (not shown) and the other end (the end on the left side in the drawing) as a tool. Spindle 103 to which is attached, and spindle 103
Radial ball bearings 104, 104 supporting the small diameter portions 103a, 103a on both ends of the housing, an acceleration pickup 105 mounted on the other end of the housing 102, and the housing 1
The rotation detector 106 arranged so as to face the small diameter portion 103a located on one end side of the main shaft 103 on the outside of 02.
And acceleration pickup 105 and rotation detector 106
It is provided with a computing unit 107 connected to the.

In this polishing apparatus 101, the main shaft 103
In adjusting the balance of the main shaft 103, the unbalance amount of the main shaft 103 is calculated by the calculation unit 107 based on the vibration value detected by the acceleration pickup 105 when the main shaft 103 is rotated and the rotation pulse obtained from the rotation detector 106. The angle was calculated. Then, based on the calculation result, for example, by attaching a weight screw 108a to the peripheral portion of the balance adjusting disc 108 provided on the front surface of the grindstone T1 and performing weight adjustment, the balance of the spindle 103 may be adjusted. It was

[0005]

However, in the above-described conventional polishing apparatus (spindle device) 101, the spindle 103 is supported by the radial ball bearings 104, 104 in a contact manner and detected by the acceleration pickup 105. Since the imbalance amount is obtained based on the vibration value, not only a minute imbalance amount cannot be measured but also the acceleration pickup 105 may erroneously detect vibration noise other than the pure vibration value. As a result, spindle 1
There is a problem that the higher the rotational speed of 03 becomes, the more difficult it becomes to perform precise adjustment, and it has been a conventional problem to solve this problem.

[0006]

SUMMARY OF THE INVENTION The present invention has been made by paying attention to the above-mentioned conventional problems. Even when the main spindle is rotated at a high speed, precise adjustment is made for a minute amount of unbalance of the main spindle. It is an object of the present invention to provide a spindle device and a spindle balance adjusting method capable of performing the above.

[0007]

A spindle device according to claim 1 of the present invention measures the displacement of a spindle, a gas bearing such as an air bearing which supports the spindle in a non-contact state in a radial direction, and the spindle. A displacement meter, a rotation detector that detects a rotation pulse of the spindle, and a calculation that calculates an unbalance amount and an angle of the spindle based on the displacement of the spindle obtained from the displacement meter and the rotation pulse obtained from the rotation detector. It is characterized in that it is provided with a section, and the structure of this spindle device is used as means for solving the conventional problems.

In the spindle device according to the second aspect of the present invention, the non-contact bearing for supporting the spindle in the non-contact state in the radial direction is provided with a bearing medium separate from the gas bearing, for example, as a hydraulic bearing or a magnetic bearing. In the main spindle device according to the third aspect of the present invention, the gas bearings are arranged on both end sides of the main spindle rather than the non-contact bearings.

Further, a spindle device according to a fourth aspect of the present invention is provided with a switching means for switching between a supporting state of the spindle by a gas bearing and a supporting state of the spindle by a non-contact bearing such as the hydraulic bearing or the magnetic bearing. In the main spindle device according to claim 5 of the present invention, the switching means is a switching valve provided between the gas bearing and its gas supply source and interlocking with the drive source of the non-contact bearing. In the spindle device according to a sixth aspect of the present invention, the switching means is an electromagnetic switching valve that makes the main shaft supported by the non-contact bearing when the power is supplied, and makes the main shaft supported by the gas bearing when the power is cut off.

Furthermore, a spindle device according to claim 7 of the present invention comprises a spindle, a fluid bearing such as an oil bearing for supporting the spindle in a non-contact state in a radial direction, and a displacement gauge for measuring the displacement of the spindle. A rotation detector that detects a rotation pulse of the spindle, and a computing unit that calculates an unbalance amount and an angle of the spindle based on the displacement of the spindle obtained from the displacement meter and the rotation pulse obtained from the rotation detector. A fluid supply source for supplying compressed gas to the fluid bearing, and a switching means for switching between liquid supply from the liquid supply source and gas supply from the gas supply source to the fluid bearing. The structure of this spindle device is used as a means for solving the conventional problems.

Furthermore, in the spindle device according to claim 8 of the present invention, the switching means is a check valve for preventing the liquid from flowing into the gas supply source, and the spindle device according to claim 9 of the present invention. In the above, the switching means is an electromagnetic switching valve which electrically connects the liquid supply source and the fluid bearing in the power supply state and electrically connects the gas supply source and the fluid bearing in the power supply cutoff state.

Furthermore, the spindle device according to claim 10 of the present invention has a structure in which a gas receiving portion such as a groove or a projection is provided in a portion of the spindle facing the bearing to which gas is supplied, and the invention is claimed. The spindle device according to No. 11 is configured such that a gas jet nozzle for jetting gas to the spindle is provided and a gas receiving portion such as a groove or a protrusion is provided at a portion of the spindle facing the gas jet nozzle.

On the other hand, in the spindle balance adjusting method according to a twelfth aspect of the present invention, when adjusting the balance of the spindle in the spindle device according to the first aspect, the spindle supported by the gas bearing is rotated to be displaced. The displacement and rotation pulse of the spindle are measured by a meter and a rotation detector, and based on the displacement of the spindle obtained from the displacement meter and the rotation pulse obtained from the rotation detector, the unbalance amount and the angle of the spindle are calculated by the calculation unit. Is calculated to adjust the balance of the spindle, and the configuration of the spindle balance adjusting method is used as means for solving the conventional problems.

Further, a spindle balance adjusting method according to a thirteenth aspect of the present invention, when adjusting the balance of the spindle in the spindle device according to any one of the second to sixth aspects, the gas bearing and the gas bearing are After the main shaft supported by the non-contact bearing provided separately with the bearing medium is supported only by the gas bearing, the main shaft is rotated, and the displacement and rotation pulse of the main shaft are measured by the displacement meter and the rotation detector. , Based on the displacement of the spindle obtained from the displacement meter and the rotation pulse obtained from the rotation detector, the calculation unit calculates the unbalance amount and angle of the spindle, and adjusts the balance of the spindle. The configuration of the spindle balance adjusting method is used as means for solving the problem.

Further, according to a fourteenth aspect of the present invention, there is provided a spindle balance adjusting method for adjusting the balance of a spindle in a spindle device according to any one of claims 7 to 9, wherein a gas is supplied from a gas supply source to a fluid bearing. Is supplied to support the spindle by gas pressure, the spindle is rotated, the displacement and rotation pulse of the spindle are measured by a displacement gauge and a rotation detector, and the displacement and rotation of the spindle obtained from the displacement gauge are measured. Based on the rotation pulse obtained from the detector, the calculation unit calculates the unbalance amount and angle of the spindle, and is characterized by adjusting the balance of the spindle. It is used as a means to solve the problem.

According to a fifteenth aspect of the present invention, there is provided a method for adjusting the balance of a spindle according to the tenth or eleventh aspect, in which the balance of the spindle is adjusted by supporting the spindle with gas pressure. The main shaft is rotated by blowing gas against the gas receiving portion of the main shaft, the displacement and rotation pulse of the main shaft are measured by a displacement meter and a rotation detector, and the displacement and rotation detector of the main shaft obtained from the displacement meter are measured. Based on the obtained rotation pulse, the arithmetic unit calculates the unbalance amount and angle of the spindle to adjust the balance of the spindle, and the structure of this spindle balance adjusting method solves the conventional problems. It is used as a means to

[0017]

In the spindle device according to the first aspect of the present invention, since the spindle is supported by the gas bearing in the non-contact state in the radial direction, the bearing rigidity is low and the displacement due to the imbalance of the spindle is small. growing.

Therefore, if the amount of displacement of the spindle detected by the displacement gauge when the spindle is rotated is input to the arithmetic unit together with the rotation pulse obtained from the rotation detector, a minute unbalance amount and phase precision of the spindle can be obtained. Therefore, accurate measurement of the spindle balance is performed.

In the spindle device according to claim 2 of the present invention,
For example, when the spindle device is a polishing device, during processing,
The main shaft is supported in the radial direction by both the gas bearing and another non-contact bearing.On the other hand, when the balance is adjusted when changing tools, the main shaft is supported only by the gas bearing. Since the bearing rigidity is reduced, the spindle is precisely adjusted in the same manner as in the spindle device according to the first aspect.

In the spindle device according to the third aspect of the present invention, the gas supplied to the gas bearing flows along the spindle to the non-contact bearing side and the end portion side of the spindle, so that the non-contact bearing is a liquid bearing. In this case, the liquid supplied to the liquid bearing is prevented from leaking to the outside of the spindle device and foreign matter outside the device from entering the inside of the spindle device.

In the spindle device according to claims 4 and 5 of the present invention, for example, when the spindle device is a polishing device, a switching means (in the spindle device according to claim 5, it is interlocked with the drive source of the non-contact bearing). The switching valve) supports the spindle in the radial direction only by the non-contact bearing during machining,
On the other hand, when adjusting the balance, such as when changing tools,
When the main shaft is supported only by the gas bearing, that is, in the main shaft device according to claim 6 of the present invention, the bearing rigidity becomes low during balance adjustment, and a large displacement can be obtained even with a minute imbalance. Therefore, precise balance adjustment of the spindle will be performed.

In the spindle device according to claim 7 of the present invention,
Since the switching means switches between the liquid supply from the liquid supply source and the gas supply from the gas supply source to the fluid bearing, it is not necessary to separately arrange the gas bearing and the fluid bearing in the axial direction, and thus the device In addition to downsizing, simplification, and cost reduction, the axial length is shortened, so that the shaft rigidity is also improved.

In the spindle device according to claim 8 of the present invention,
For example, when the spindle device is a polishing device, when the liquid is supplied from the liquid supply source to the fluid bearing at a pressure higher than the gas pressure from the gas supply source during processing, the spindle is supported by the hydraulic pressure. At this time, the check valve prevents the liquid from flowing into the gas supply source.

On the other hand, when the liquid supply from the liquid supply source is stopped at the time of balance adjustment at the time of exchanging the tool, the gas is supplied from the gas supply source to the fluid bearing instead of the liquid, and the main shaft is Since it is supported by gas pressure, precise balance adjustment of the spindle is performed, and thus, when liquid supply from the liquid supply source is stopped, gas is automatically supplied to the fluid bearing. Therefore, for example, seizure of the bearing and damage to the main shaft can be avoided during a power failure.

In the spindle device according to claim 9 of the present invention,
Since the liquid supply and the gas supply to the fluid bearing are switched by the electromagnetic switching valve, for example, at the time of power failure, the residual pressure of the gas supply source causes the fluid bearing (gas in addition to the gas in the fluid bearing, regardless of the pressure difference between the fluid and the gas). When a bearing is provided separately, gas is reliably supplied to this gas bearing, and the main shaft is supported by the gas pressure, so that seizure of the bearing and damage to the main shaft are avoided.

In the spindle device according to the tenth and eleventh aspects of the present invention, when the gas is injected into the gas receiving portion of the spindle when the balance of the spindle is adjusted at the time of exchanging a tool or the like, the spindle operates a driving portion such as a motor. The motor rotates without being driven, and as a result, a pure amount of imbalance of the main shaft that is not affected by vibration noise of the drive unit is measured.

On the other hand, in the spindle balance adjusting method according to claims 12 to 14 of the present invention, when the balance of the spindle in the spindle device according to claims 1 to 9 is adjusted, the spindle is supported by gas pressure. Since the bearing is rotated, the rigidity of the bearing is lowered. Therefore, the minute unbalance amount and the phase of the spindle are precisely measured, and the precise balance adjustment of the spindle is performed. According to the balance adjusting method, claims 10 and 1
When adjusting the balance of the main spindle in the main spindle device described in 1, the main spindle is rotated by blowing gas without activating the drive unit such as a motor, so that the main shaft is not affected by vibration noise of the drive unit. The imbalance amount is measured.

[0028]

Since the spindle device according to the first aspect of the present invention has the above-mentioned configuration, it is possible to perform a precise measurement of the minute unbalance amount and phase of the spindle. Balance adjustment is possible, and moreover,
This has a very excellent effect that this adjustment work can be performed on the device.

Further, in the main spindle device according to the second aspect of the present invention, for example, when the main spindle device is a polishing device, at the time of machining, a gas bearing and a non-contact bearing provided with a bearing medium separate from the gas bearing are provided. When the main shaft is supported in the radial direction by both of them, while the main shaft is supported only by the gas bearing when the balance is adjusted at the time of exchanging the tool, the same effect as the main shaft device according to claim 1 can be obtained. In addition to the above, a very excellent effect that the bearing rigidity can be kept high at the time of processing is brought about.
When the non-contact bearing is a liquid bearing, it is very excellent in that it is possible to prevent leakage of the liquid supplied to the liquid bearing to the outside of the device and intrusion of foreign matter into the device. The effect is brought.

Further, in the spindle device according to claims 4 and 5 of the present invention, for example, when the spindle device is a polishing device, switching means (in the spindle device according to claim 5, a drive source for the non-contact bearing When machining, the main shaft is supported in the radial direction only by the non-contact bearing, while the main shaft is supported only by the gas bearing during balance adjustment when exchanging tools.
That is, the spindle device according to the sixth aspect of the present invention has a very excellent effect that the spindle rigidity can be precisely adjusted on the device while maintaining high bearing rigidity during machining. Be brought.

Furthermore, since the spindle device according to claim 7 of the present invention has the above-described structure, the same effect as that of the spindle device according to claim 2 can be obtained, and the device can be downsized and the structure can be simplified. Of the present invention, it is possible to improve the shaft rigidity, and in the spindle device according to claim 8 of the present invention, for example, when the spindle device is a polishing device, the spindle device according to claim 7 In addition to the same effect as the device, it is possible to prevent seizure of the bearing and damage to the main shaft when the liquid supply from the liquid supply source is stopped, for example, at the time of power failure. In addition to obtaining the same effect as the main shaft device according to Item 7, for example, at the time of power failure, regardless of the pressure difference between the liquid and the gas, the residual pressure of the gas supply source causes the hydrodynamic bearing (fluid shaft). If a separate gas bearing is provided, the gas can be reliably supplied to this gas bearing, and the main shaft can be supported by gas pressure, so it is possible to prevent seizure of the bearing and damage to the main shaft. It has a very excellent effect of being able to do.

Furthermore, claims 10 and 1 of the present invention
In the spindle device according to No. 1, the spindle can be rotated without operating the drive unit such as a motor when adjusting the balance of the spindle during tool replacement, etc., so that it is not affected by vibration noise of the drive unit. This has the great advantage of being able to measure the pure amount of unbalance of the spindle.

On the other hand, in the spindle balance adjusting method according to claims 12 to 14 of the present invention, when the balance of the spindle in the spindle device according to claims 1 to 9 is adjusted, the spindle is rotated while being supported by gas pressure. As a result, it is possible to perform a precise measurement of the minute unbalance amount and phase of the spindle, and as a result, a very excellent effect that the spindle can be precisely balanced can be obtained. In the spindle balance adjusting method according to Item 15, when adjusting the balance of the spindle in the spindle device according to Claims 10 and 11, the spindle is rotated by blowing gas without operating a drive unit such as a motor. It is possible to measure a pure unbalance amount of the spindle that is not affected by vibration noise of the drive part, and as a result, It results in a very excellent effect that it is possible to perform a layer precise balancing.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

[First Embodiment] FIG. 1 shows an embodiment of a spindle device according to claims 1 and 2 of the present invention. In this embodiment, the spindle device according to the present invention is a polishing device. Indicates.

As shown in FIG. 1, the polishing apparatus 1 includes a housing 2, a housing 2, and one end (the end on the right side in the drawing) of which is connected to a drive unit (not shown) and the other end. Located on both sides of the main shaft 10 to which a grindstone T as a tool is attached, and a large diameter part 11 provided at an intermediate portion of the main shaft 10, and small diameter parts 12, 1 of the main shaft 10
Hydrostatic air bearing (gas bearing) that supports 2 in the radial direction
3, 3 and a static pressure oil bearing which is located on both ends of the main shaft 10 with respect to the static pressure air bearings 3, 3 and supports the small diameter portions 12, 12 in a radial direction in a non-contact state (what is a static pressure air bearing? Non-contact bearings 4 and 4 with separate bearing medium, and air supply passage 3
an air source 5 for supplying compressed air to the static pressure air bearings 3, 3 via a, an oil feed pump 6 for sending oil under pressure to the static pressure oil bearings 4, 4 via an oil feed passage 4a, and a main shaft 10. A displacement gauge 7 mounted on the housing 2 so as to face the small-diameter portion 12 on the tool mounting side, a rotation detector 8 mounted on the housing 2 so as to face the small-diameter portion 12 on the drive portion side of the main shaft 10, and a displacement A calculation unit 9 electrically connected to the total 7 and the rotation detector 8 is provided.

In this polishing apparatus 1, at the time of polishing, compressed air is supplied from the air source 5 to the static pressure air bearings 3, 3 via the air supply passage 3a, and at the same time from the oil feed pump 6 via the oil feed passage 4a. By sending oil to the hydrostatic oil bearings 4 and 4 by
The main shaft 10 is supported by both the static pressure air bearings 3 and 3 and the static pressure oil bearings 4 and 4, and the bearing rigidity is maintained high during processing.

On the other hand, in this polishing apparatus 1, when adjusting the balance of the spindle 10 when replacing the grindstone T, the oil feed pump 6 is stopped and the spindle 10 is supported only by the air pressure of the static pressure air bearings 3, 3. By so doing, the bearing rigidity is lowered.

That is, when adjusting the balance of the main shaft 10, the main shaft 10 supported only by the air pressure is rotated, and at this time, the displacement amount of the main shaft 10 detected by the displacement gauge 7 is obtained from the rotation detector 8. When input to the calculation unit 9 together with the pulse, the minute unbalance amount and phase of the spindle 10 are precisely measured, and therefore the spindle 10 is precisely balanced based on the measurement result. For example, if the weight screw 13a is attached to the balance adjustment disk 13 provided on the front surface of the grindstone T, the balance adjustment work of the spindle 10 will be performed on the apparatus.

[Second Embodiment] FIG. 2 shows claims 1 to 3 of the present invention.
3 shows an example of a spindle device according to No. 3, and also in this embodiment, the case where the spindle device according to the present invention is a polishing device is shown.

As shown in FIG. 2, the polishing apparatus 21 according to this embodiment is different from the polishing apparatus 1 in the first embodiment in that the static pressure air bearings 3 and 3 and the static pressure oil bearings 4 and 4 are different. The positions of arrangement are changed to each other, that is, the static pressure air bearings 3,
3 is arranged on both end sides of the main shaft 10 with respect to the hydrostatic oil bearings 4 and 4, and other configurations are the same as those of the polishing apparatus 1 in the first embodiment.

In this polishing device 21, the spindle 10 is precisely adjusted in the same manner as in the polishing device 1, and in addition, both the static pressure air bearings 3 and 3 and the static pressure oil bearings 4 and 4 are used. At the time of polishing for supporting 10, the compressed air supplied to the static pressure air bearings 3, 3 flows along the main shaft 10 toward the static pressure oil bearings 4, 4 and both ends of the main shaft 10, so that the static pressure Both the leakage of the oil supplied to the oil bearings 4 and 4 to the outside of the device and the intrusion of foreign matter into the device are prevented.

[Third Embodiment] FIG. 3 shows claims 1 and 2 of the present invention.
An example of the spindle device relating to Nos. 2, 4 to 6 is shown, and also in this embodiment, the case where the spindle device according to the present invention is a polishing device is shown.

As partially shown in FIG. 3, in the polishing apparatus 31 according to this embodiment, the hydrostatic oil bearings 4, 4 are provided on the air supply passage 3a between the hydrostatic air bearings 3, 3 and the air source 5. 4 is provided with a switching valve 32 that is interlocked with the oil feed pump 6 as a drive source, and shuts off the compressed air supplied to the static pressure air bearings 3, 3 when the oil feed pump 6 is operating, and stops the oil feed pump 6. Occasionally, compressed air is supplied to the static pressure air bearings 3, 3, and the other structure is the same as that of the polishing apparatus 1 in the first embodiment.

That is, in the polishing apparatus 31, during the polishing process, the oil feed pump 6 is operated to shut off the supply of compressed air to the static pressure air bearings 3 and 3 and the static pressure oil bearings 4 and 4.
By supporting the main shaft 10 only by itself, the bearing rigidity is kept high, and during balance adjustment of the main shaft 10,
The oil feed pump 6 is stopped and compressed air is supplied to the static pressure air bearings 3,
3, the main shaft 10 is supported only by the hydrostatic air bearings 3 and 3 to reduce the bearing rigidity, whereby the main shaft 10 is precisely balanced.

[Fourth Embodiment] FIG. 4 shows claims 1 and 2 of the present invention.
An example of a spindle device according to Nos. 7 and 8 is shown, and also in this embodiment, a case where the spindle device according to the present invention is a polishing device is shown.

As shown in FIG. 4, the polishing apparatus 41 is
A housing 42 and one end (the end on the right side in the drawing) housed in the housing 41 are connected to a drive unit (not shown), and a grindstone T as a tool is attached to the other end (the end on the left side in the drawing). The main shaft 10 and the static pressure oil bearings (fluid bearings) 44, 44 for radially supporting the small diameter portions 12, 12 provided on both ends of the main shaft 10, and the static pressure oil bearing 44 via the oil feed passage 44a. An oil feed pump 46 that feeds oil under pressure, and an air source 4 that communicates with an oil feed passage 44a via an air supply passage 43a.
5 and a check valve 43 provided in the air supply passage 43a, and other configurations are the same as those of the polishing apparatus 1 according to the first embodiment.

In the spindle device 41, when the oil feed pump 46 is operated to supply oil to the hydrostatic oil bearings 44, 44 at a pressure higher than the air pressure from the air source 45 during polishing, the oil is compressed. Static pressure oil bearings 44, 4 that push air away
4, the main shaft 10 is hydraulically supported,
The bearing rigidity will be kept high during polishing.
At this time, the check valve 43 prevents the oil from flowing into the air source 45.

On the other hand, when the oil feed pump 46 is stopped during balance adjustment of the main shaft 10, the hydrostatic oil bearings 44,
Compressed air is supplied from the air source 45 instead of oil to 44, and the main shaft 10 is supported by gas pressure, so that precise balance adjustment of the main shaft 10 is performed.

As described above, in the spindle device 41, when the balance is adjusted, the hydrostatic oil bearing 44 functions as a hydrostatic air bearing, so that the hydrostatic air bearing and the hydrostatic oil bearing are arranged side by side in the axial direction. Compared with the above, the size and the simplification and the cost can be reduced, and the axial rigidity is improved by the reduction of the axial length. In addition, when the oil feed pump 46 is stopped, the static pressure is reduced. Since compressed air is automatically supplied to the oil bearing 44, seizure of the hydrostatic oil bearing 44 and damage to the main shaft 10 are avoided, for example, during a power failure.

[Fifth Embodiment] FIG. 5 shows claims 1 and 2 of the present invention.
An example of the spindle device relating to Nos. 7 and 9 is shown, and in this embodiment as well, the case where the spindle device according to the present invention is a polishing apparatus is shown.

As shown partially in FIG. 5, this polishing device 51 is different from the polishing device 41 in the fourth embodiment in that the static pressure is applied to the air supply passage 43a and the oil feed passage 44a via the electromagnetic switching valve 53. The oil is communicated with the oil bearing 44, and the oil is supplied to the hydrostatic oil bearing 44 by the operation of the electromagnetic switching valve 53 when the power is supplied, and the compressed air is stopped by stopping the oil feed pump 46 and the returning operation of the electromagnetic switching valve 53 when the power is cut off. Pressure oil bearing 44
The point is to supply to.

In this polishing apparatus 51, the oil feed pump 4
At the time of stop of 6, regardless of the pressure difference between hydraulic pressure and air pressure,
Compressed air is reliably supplied to the hydrostatic oil bearings 44, 44 by the residual pressure of the air source 45, and the main shaft 10 is supported by the air pressure. Therefore, for example, at the time of power failure, the polishing device 41 in the previous embodiment. Similarly, seizure of the hydrostatic oil bearing 44 and damage to the main shaft 10 are avoided.

[Sixth Embodiment] FIG. 6 shows claims 1 and 2 of the present invention.
An example of a spindle device according to Nos. 2 and 11 is shown, and also in this embodiment, the case where the spindle device according to the present invention is a polishing device is shown.

As shown in FIG. 6, the polishing apparatus 61 is
In the polishing apparatus 1 of the first embodiment, the main shaft 10 is provided between the static pressure air bearing 3 and the static pressure oil bearing 4 on the drive unit side (the right side in the drawing).
An air injection nozzle 3A for injecting compressed air to A is provided, and a plurality of grooves (gas receiving portions) 1 are provided in a portion of the main shaft 10A facing the air injection nozzle 3A of the small diameter portion 12A.
0a is arranged in a ring.

In this polishing apparatus 61, when the balance of the spindle 10A is adjusted when the tool is replaced, the spindle 1
When compressed air is injected into the groove 10a of 0A, the main shaft 10A rotates without operating the drive unit, so that the pure unbalance amount of the main shaft 10A that is not affected by the vibration noise of the drive unit is measured. The Rukoto.

In the above-mentioned embodiment, the case where the spindle device and the spindle balance adjusting method according to the present invention are applied to the polishing apparatus is shown, but the present invention is not limited to this.

Further, the detailed configurations of the spindle device and the spindle balance adjusting method according to the present invention are not limited to the above embodiments.

[Brief description of drawings]

FIG. 1 is a cross-sectional explanatory view showing a first embodiment of a spindle device according to the present invention.

FIG. 2 is an explanatory sectional view showing a second embodiment of the spindle device according to the present invention.

FIG. 3 is a piping explanatory view showing a third embodiment of the spindle device according to the present invention.

FIG. 4 is an explanatory sectional view showing a fourth embodiment of a spindle device according to the present invention.

FIG. 5 is a piping explanatory view showing a fifth embodiment of the spindle device according to the present invention.

FIG. 6 is an explanatory sectional view showing a sixth embodiment of the spindle device according to the present invention.

FIG. 7 is a cross-sectional explanatory view showing a conventional spindle device.

[Explanation of symbols]

1, 21, 31, 41, 51, 61 Polishing device (spindle device) 3 Static pressure air bearing (gas bearing) 3A Air injection nozzle (gas injection nozzle) 4,44 Static pressure oil bearing (fluid bearing; gas bearing) Non-contact bearing with separate bearing medium) 7 Displacement meter 8 Rotation detector 9 Calculation part 10, 10A Main shaft 10a Groove (gas receiving part) 32 Switching valve (switching means) 43 Check valve (switching means) 53 Electromagnetic switching valve ( Switching means)

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yu Owada Nissan Motor Co., Ltd. (2) 2 Takaracho, Kanagawa-ku, Yokohama, Nissan Motor Co., Ltd. (72) Toshikazu Otani 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (72) Inventor Manabu Wakuda, Nissan Motor Co., Ltd., 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture (72) Inventor Minoru Ota 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture, Nissan Motor Co., Ltd. (72) Miya, Inventor Katsutoshi Hara 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Prefecture Nissan Motor Co., Ltd.

Claims (15)

[Claims] 1. A main shaft, a gas bearing that supports the main shaft in a radial direction in a non-contact state, a displacement meter that measures the displacement of the main shaft, a rotation detector that detects a rotation pulse of the main shaft, and the displacement meter. A spindle device, comprising: a calculation unit that calculates an unbalance amount and an angle of the spindle based on a displacement of the spindle obtained from the above and a rotation pulse obtained from a rotation detector. 2. The spindle device according to claim 1, wherein a non-contact bearing for supporting the spindle in a non-contact state in a radial direction is provided separately from the gas bearing as a bearing medium. 3. The spindle device according to claim 2, wherein the gas bearing is arranged on both end sides of the spindle with respect to the non-contact bearing. 4. A main shaft is supported by the gas bearing,
4. The spindle device according to claim 2, further comprising switching means for switching between a state where the spindle is supported by the non-contact bearing. 5. The spindle device according to claim 4, wherein the switching means is a switching valve which is provided between the gas bearing and the gas supply source thereof and which is interlocked with the drive source of the non-contact bearing. 6. The spindle device according to claim 4, wherein the switching means is an electromagnetic switching valve that makes the main shaft supported by the non-contact bearing when the power is supplied, and makes the main shaft supported by the gas bearing when the power is cut off. . 7. A spindle, a fluid bearing for supporting the spindle in a radial direction in a non-contact state, a displacement gauge for measuring the displacement of the spindle, a rotation detector for detecting a rotation pulse of the spindle, and the displacement gauge. And a gas supply source for supplying compressed gas to the fluid bearing, which is provided with an arithmetic unit for calculating an unbalance amount and an angle of the spindle based on a displacement of the spindle obtained from the rotation pulse and a rotation pulse obtained from a rotation detector. At the same time, a spindle device is provided, which is provided with a switching means for switching between liquid supply from a liquid supply source and gas supply from a gas supply source to the fluid bearing. 8. The spindle device according to claim 7, wherein the switching means is a check valve that prevents the liquid from flowing into the gas supply source. 9. The main shaft according to claim 7, wherein the switching means is an electromagnetic switching valve which electrically connects the liquid supply source and the fluid bearing when the power is supplied and electrically connects the gas supply source and the fluid bearing when the power is shut off. apparatus. 10. The spindle device according to claim 1, wherein a gas receiving portion is provided at a portion of the spindle facing the bearing to which the gas is supplied. 11. The spindle device according to claim 1, wherein a gas jet nozzle for jetting gas to the spindle is provided, and a gas receiving portion is provided at a portion of the spindle facing the gas jet nozzle. . 12. When adjusting the balance of the spindle in the spindle device according to claim 1, the spindle supported by a gas bearing is rotated, and the displacement and rotation pulse of the spindle are measured by a displacement gauge and a rotation detector. Then, based on the displacement of the spindle obtained from the displacement meter and the rotation pulse obtained from the rotation detector, the unbalance amount and the angle of the spindle are calculated by the calculation unit, and the balance of the spindle is adjusted. How to adjust the balance of the spindle. 13. When adjusting the balance of the spindle in the spindle device according to any one of claims 2 to 6,
A gas bearing and a main shaft supported by a non-contact bearing provided separately from the gas bearing are supported only by the gas bearing, and then the main shaft is rotated, and the main shaft is rotated by a displacement gauge and a rotation detector. Displacement and rotation pulse of
Based on the displacement of the spindle obtained from the displacement meter and the rotation pulse obtained from the rotation detector, the unbalance amount and the angle of the spindle are calculated by the arithmetic unit, and the balance of the spindle is adjusted. Balance adjustment method. 14. When adjusting the balance of the spindle in the spindle device according to claim 7,
After supplying gas from the gas supply source to the fluid bearing to support the main shaft by gas pressure, the main shaft is rotated, and the displacement and rotation pulse of the main shaft are measured by a displacement meter and a rotation detector, and the displacement meter. Based on the displacement of the spindle obtained from the above and the rotation pulse obtained from the rotation detector, the unbalance amount and the angle of the spindle are calculated by the arithmetic unit, and the balance of the spindle is adjusted. Method. 15. When adjusting the balance of the spindle in the spindle device according to claim 10 or 11, the spindle is supported by gas pressure, and then the spindle is rotated by blowing gas onto a gas receiving portion of the spindle. Then, the displacement and the rotation detector measure the displacement and rotation pulse of the main spindle, and based on the displacement of the main spindle obtained from the displacement gauge and the rotation pulse obtained from the rotation detector, the unbalance of the main spindle by the calculation unit. A method for adjusting the balance of a spindle, which comprises calculating a quantity and an angle to adjust the balance of the spindle.