JP2000065057A - Magnetic bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic bearing capable of transmitting the type of a spindle from the spindle side to a controller and capable of automatically adjusting a set value such as a control constant on the controller side even if a magnetic bearing spindle is the different type. SOLUTION: In a magnetic bearing spindle 1, recognizing information for recognizing a spindle by a switch 15 can be set, the recognizing information is fed back to a controller 50, and a microcomputer 51 recognizes the magnetic bearing spindle, reads a previously stored control constant, and drives respective magnetic bearings and a motor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic bearing device, and more particularly to a magnetic bearing device used for a vacuum pump for obtaining a high vacuum and for magnetically bearing a rotating shaft of a turbo molecular pump spindle.

[0002]

2. Description of the Related Art FIG. 5 is a diagram showing a configuration of a conventional magnetic bearing spindle. In FIG. 5, a magnetic bearing spindle 1 for a turbo molecular pump spindle has a rotating shaft 3 provided in a case 2, a thrust magnetic bearing 4 provided substantially at the center of the rotating shaft 3, and a thrust magnetic bearing 4. The radial magnetic bearings 5 and 6 provided above and below the rotary shaft 4 support the rotating shaft 3 in the thrust and radial directions in a non-contact manner, and are rotationally driven by a driving motor 7. The radial position of the rotating shaft 3 is detected by the radial position sensors 8 and 9, and the thrust position is detected by the thrust position sensor 10. Protective ball bearings 11, 12 for bearing the rotary shaft 3 when the radial magnetic bearings 5, 6 are abnormal are arranged above and below the rotary shaft 3.

The detection output of each of the sensors 8, 9, and 10 is given to a controller 50 provided outside, and the controller 50 controls each of the magnetic bearings 4, 5, and 6 according to a command from an external system controller 60, and By driving the rotating shaft 7, the rotating shaft 3 of the magnetic bearing spindle 1 rotates.

[0004]

There are many types of magnetic bearing spindles used for turbo-molecular pumps, depending on the shape of the spindle and the difference in the rotor attached to the spindle. Until now, depending on the type of each of these spindles, it was necessary to optimally set the control constant of the magnetic bearing controller, the motor speed, and the like. Because such settings are required, the manufactured controller can be applied only to a specific type of magnetic bearing spindle, and in order to apply it to other types of magnetic bearing spindles, many settings such as control constants in the controller are required. There was a problem that the value had to be changed.

Therefore, the main object of the present invention is to transmit the spindle type from the spindle side to the controller even if the magnetic bearing spindle is of a different type, and the controller automatically adjusts set values such as control constants. An object of the present invention is to provide a magnetic bearing device that can perform the above.

[0006]

The invention according to claim 1 is
In a magnetic bearing device of a spindle having a position sensor for detecting a position of a rotating body and a magnetic bearing for magnetically supporting the rotating body in a non-contact manner, a code for identifying the spindle is set in a spindle body. And a control means for identifying the code set by the switch and performing optimal control on the spindle.

In the invention according to claim 2, voltage setting means for outputting a voltage for identifying the spindle is provided in the spindle main body, and the set voltage is identified to perform optimal control for the spindle. And control means for performing the control.

According to a third aspect of the present invention, the control means of the first or second aspect includes a memory for storing an appropriate control constant corresponding to each of the spindles, and the control means corresponding to a command from the spindle body. The constant is read and the corresponding spindle body is controlled.

[0009]

FIG. 1 is a diagram showing an embodiment of the present invention. In FIG. 1, a plurality of switches 15 are built in the magnetic bearing spindle 1. By turning on / off the switches 15, information for identifying the magnetic bearing spindle 1 is transmitted to the controller 50 side. The controller 50 includes a microcomputer 51
Are stored in advance, and control constants for correcting variations in physical characteristics of the respective magnetic bearing spindles 1 are stored in advance. When the microcomputer 51 identifies the magnetic bearing spindle 1, it reads out a control constant corresponding to the magnetic bearing spindle 1 and controls the thrust magnetic bearing 4, the radial magnetic bearings 5, 6, and the motor 7. As described above, since information for identifying each magnetic bearing spindle is set by the mechanical switch 15, malfunction due to noise or the like can be reduced.

FIG. 2 is a diagram showing another embodiment of the present invention. In the example shown in FIG. 1 described above, information for identifying the magnetic bearing spindle 1 is transmitted to the controller 50 by the switch 15, but in the embodiment shown in FIG. 1 and the magnetic bearing spindle 1 has resistors R1 and R
A divided voltage for identifying the magnetic bearing spindle 1 is set by the ratio of 2, and the voltage is sent back to the controller 52. On the other hand, the controller 52 has a microcomputer 51 and an A / D converter 53 built therein, and the A / D converter converts the voltage sent back from the magnetic bearing spindle 1 into a digital signal and sends the signal to the microcomputer 51. The microcomputer 51 identifies the magnetic bearing spindle 1 based on the digital signal. The subsequent operation is the same as in FIG.

FIG. 3 is a diagram showing still another embodiment of the present invention. In the embodiment shown in FIG. 2 described above, the power is supplied from the controller 52 to the magnetic bearing spindle 1 and the voltage divided by the resistors R1 and R2 is sent back to the controller 52, as shown in FIG. In the example, the power supply device 20 is built in the magnetic bearing spindle 1, a voltage for identifying the magnetic bearing spindle 1 is generated from the power supply device 20, and the voltage is identified on the controller 52 side. Other operations are the same as those in FIG.

FIG. 4 is a block diagram showing the configuration of the microcomputer shown in FIGS. The microcomputer 51 includes a CPU 54, a ROM 55, and a RAM 56. The ROM 55 stores a program for the CPU 51 to control the magnetic bearing spindle 1.
In M56, the control constant for each magnetic bearing spindle described in each of the above embodiments is stored.

[0013]

As described above, according to the present invention, the magnetic bearing spindle can be automatically judged by the control means simply by connecting the magnetic bearing spindle main body to the control means. If a control constant is set for each type and the magnetic bearing spindle can be identified, the corresponding control constant can be read and controlled.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of another embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of still another embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of the microcomputer shown in FIGS.

FIG. 5 is a sectional view showing a configuration of a conventional magnetic bearing spindle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnetic bearing spindle 15 Switch 20 Power supply 50, 52 Controller 53 A / D converter 51 Microcomputer 55 ROM 56 RAM

 ────────────────────────────────────────────────── ─── Continued on the front page F term (reference) 3J102 AA01 BA03 BA17 BA18 CA11 CA14 CA27 DB01 DB05 DB22 DB38 GA06 5H607 AA12 AA14 BB01 BB14 CC01 CC07 DD03 GG21 HH01

Claims (3)

[Claims] 1. A position sensor for detecting a position of a rotating body,
A magnetic bearing device for a spindle having a magnetic bearing for magnetically supporting the rotating body in a non-contact manner, wherein a switch for setting a code for identifying the spindle is provided in the spindle main body,
The magnetic bearing device further includes control means for identifying a code set by the switch and performing optimal control on the spindle. 2. A position sensor for detecting a position of a rotating body,
In a magnetic bearing device for a spindle having a magnetic bearing for magnetically supporting the rotating body in a non-contact manner, voltage setting means for outputting a voltage for identifying the spindle is provided in the spindle main body. ,
The magnetic bearing device further includes control means for identifying the voltage set by the voltage setting means and performing optimal control on the spindle. 3. The control means includes a memory for storing an appropriate control constant corresponding to each of the spindles,
The magnetic bearing device according to claim 1, wherein a corresponding control constant is read in response to a command from the spindle main body to control the corresponding spindle main body.