JP2000065056A - Magnetic bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magnetic bearing capable of being driven by previously storing the variation in physical characteristics in a main body and correcting the variation. SOLUTION: An information processing circuit 20 is housed in the lower part of a spindle main body 1, the information processing circuit 20 is composed of one tip microcomputer, initial state information of physical characteristics such as the insulating resistance of an electromagnetic coil and the spindle main body and the electromagnetic coil resistance and the allowable change amount are previously stored, as initial state information of a spindle in a RAM, and a CPU can grasp the state of the spindle on the basis of the data as necessary.

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 spindle of a turbo molecular pump or the like, and supporting a rotary shaft in a radial direction and a thrust direction by a magnetic bearing.

[0002]

2. Description of the Related Art A magnetic bearing device of a spindle for a turbo-molecular pump has two radial magnetic bearings and one thrust bearing, and has two radial position sensors and one thrust position sensor. I have. The radial magnetic bearing performs a radial bearing above and below the rotating shaft in a non-contact manner, and the thrust magnetic bearing performs a thrust bearing near the center of the rotating shaft in a non-contact manner. Each of these magnetic bearings is constituted by an electromagnet. Then, based on the detection outputs of the two radial position sensors and one thrust position sensor, the corresponding magnetic bearings are controlled and rotated by the driving force of the motor.

[0003]

In order to check the state of each component constituting the magnetic bearing device, the insulation resistance between the electromagnet coil and the spindle body, the coil resistance of the electromagnet, the sensor coil resistance, and the motor coil resistance must be checked. It is necessary to measure the insulation resistance between the motor coil and the spindle main body and compare it with the data at the time of manufacturing the spindle. The measurement of such data is performed by the technician of the manufacturer at the installation site, and there is a problem that much labor and cost are required to compare with the initial data of each spindle.

Accordingly, a main object of the present invention is to provide a magnetic bearing device in which physical characteristic data of a spindle component is stored in a main body in advance, and the initial data and measured data can be compared as required. It is to provide.

[0005]

The invention according to claim 1 is
A magnetic bearing body having a position sensor for detecting the position of the rotating body and a magnetic bearing device for magnetically supporting the rotating body in a non-contact manner, connected to the magnetic bearing body via a cable, based on an output signal from the position sensor; Control means for controlling the magnetic bearing, and information processing means for storing and processing an initial state of physical characteristics of the magnetic bearing or an allowable variation range of the physical characteristics, which is built in the magnetic bearing main body. Be composed.

According to a second aspect of the present invention, the information processing means of the first aspect comprises a one-chip microcomputer or a digital signal processor having a built-in CPU, ROM and RAM.

[0007]

FIG. 1 is a view showing the configuration of a turbo molecular pump spindle according to one embodiment of the present invention.

In FIG. 1, a magnetic bearing spindle 1 comprises:
A rotating shaft 3 is provided in the case 2, and is rotated by a thrust magnetic bearing 4 provided substantially at the center of the rotating shaft 3 and radial magnetic bearings 5 and 6 provided above and below the thrust magnetic bearing 4. The shaft 4 is supported in the thrust and radial directions in a non-contact manner, and is driven to rotate by a driving motor 7. Further, the radial position of the rotating shaft 3 is detected by the radial position sensors 8 and 9, the thrust position is detected by the thrust position sensor 10, and the rotation speed is detected by the rotation speed sensor 13. Further, protective ball bearings 11 and 12 for bearing the rotating shaft 3 when the radial magnetic bearings 5 and 6 are abnormal are arranged above and below the rotating shaft 3.

Further, an information processing unit 20 is provided below the case 2.
Is built-in. As the information processing unit 20, a one-chip microcomputer described later is used.
The information processing section 20 is connected to a controller 50 provided separately from the magnetic bearing main body 1, and the controller 50 is connected to an external system controller 60.

FIG. 2 is a specific block diagram of the information processing section 20 shown in FIG. 2, a one-chip microcomputer 40 includes a CPU 41, a ROM 42, and a RAM.
43, and the ROM 42 has a CPU 41
Stores a program necessary for the operation of
The AM 43 stores an initial value of each physical characteristic of the corresponding magnetic bearing spindle or an allowable change width of the physical characteristic. The one-chip microcomputer 40 is connected to the I / O interface 44, and the I / O interface 44
Are connected to A / D converters 21 to 25. A / D
The output of the coil resistance measuring device 31 of the electromagnet is given to the converter 21, the output of the insulation resistance measuring device 32 between the coil of the electromagnet and the spindle body is given to the A / D converter 22,
The output of the sensor coil resistance measuring device 33 is given to the A / D converter 23. The output of the motor coil resistance measuring device is given to the A / D converter 24. The output of the insulation resistance measuring device 25 between the motor coil and the spindle main body is given to the A / D converter 25. Output signals of these A / D converters 21 to 25 are sent to CPU 4 via I / O interface 44.
1 and is compared with information stored in the RAM 43 in advance.

In this embodiment, the initial information of the spindle includes insulation resistance between the electromagnet coil and the spindle body,
Electromagnetic coil resistance, sensor coil resistance, motor coil resistance, insulation resistance between the motor coil and the spindle main body, the allowable change width of these initial state information, and information on the spindle type are stored in the RAM 43, and the CPU 41 stores these information during driving. It is possible to read out the data, compare the current measurement data with the initial information as needed, and grasp the spindle state from the allowable change width of the initial state information.

Further, in the embodiment of the present invention, since the information processing circuit 20 is built in the spindle main body 1, it is possible to check the pump and judge the situation by the spindle main body 1 alone. Moreover, an external controller 5
Even in the case where the system within 0 is out of order, the spindle main body 1 can cope with it. The information processing circuit 20 is not limited to the one-chip microcomputer 40, but may be a digital signal processor (DSP) or an IC card. In this case, it is possible to analyze the internal data at another place where the IC card is taken out and separated, thereby increasing the versatility.

[0013]

As described above, according to the present invention, an information processing means for storing and processing the initial state or the allowable change width of the physical characteristics of the magnetic bearing in the magnetic bearing body is provided. Therefore, the physical characteristics of each magnetic bearing device can be stored, and the information can be read as needed to grasp the state of the magnetic bearing.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a turbo molecular spindle according to an embodiment of the present invention.

FIG. 2 is a specific block diagram of an information processing circuit built in the magnetic bearing spindle main body shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spindle main body 2 Case 3 Rotating shaft 4 Thrust magnetic bearing 5,6 Radial magnetic bearing 7 Motor 8,9 Radial position sensor 10 Thrust position sensor 11,12 Protective ball bearing 21-25 A / D converter 31 Coil resistance of electromagnet Measuring device 32 Insulation resistance measuring device 33 Sensor coil resistance measuring device 34 Motor coil resistance measuring device 35 Insulation resistance measuring device 40 1-chip microcomputer 41 CPU 42 ROM 43 RAM 44 I / O interface 50 Controller

Claims (2)

[Claims] 1. A magnetic bearing body having a position sensor for detecting a position of a rotating body and a magnetic bearing for supporting the rotating body in a magnetically non-contact manner, the magnetic bearing body being connected to the magnetic bearing body via a cable, wherein the position is Control means for controlling the magnetic bearing based on an output signal from a sensor; and a built-in magnetic bearing main body, which stores an initial state of physical characteristics of the magnetic bearing or an allowable change width of the physical characteristics, and processes A magnetic bearing device comprising: 2. The magnetic bearing device according to claim 1, wherein said information processing means comprises a one-chip microcomputer or a digital signal processor having a built-in CPU, ROM and RAM.