JP3100346B2 - Turbo molecular pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a turbo-molecular pump of the controlled magnetic bearing type.

[0002]

2. Description of the Related Art FIG. 5 is a side view showing a structure of a magnetic bearing portion using an electromagnet as a conventional means for floatingly holding a rotating body. In FIG. 5, reference numeral 4 denotes a rotating body, a pair of magnetic bearings (journal bearings) 5a and 5b rotatably support the rotating body 4, and position sensors 6a and 6b detect a floating position of the rotating body 4.

With such a configuration, the floating position of the rotating body 4 is detected by the position sensors 6a and 6b. Based on the detection signals obtained at that time, the value of a current flowing through electromagnets (not shown) provided in the magnetic bearings 5a and 5b is determined, and the magnitude of the magnetic force generated from the electromagnets is controlled to determine the floating position of the rotating body 4. Try to keep it in the center.

FIG. 6 is a block diagram showing a control circuit of the above-described magnetic bearing. In FIG. 6, 1 is a power supply device, 2
Is a pump body. 8 is a magnetic bearing control circuit, 9 is a magnetic bearing drive circuit, 10 is a magnetic bearing drive power supply, 12 is a motor drive circuit, and 3 is a part (circuit) that limits compatibility between models. Further, 7 in the pump body 2 is a position sensor, 11 is an electromagnet, and 13 is a motor.

The magnetic bearing control circuit 8A and the magnetic bearing drive circuit 9B, which are components of the part 3 for limiting the compatibility between the above-mentioned models, are control circuits for maintaining the floating position of the rotating body at the center. (For example, a PID control circuit that is a proportional element, an integral element, and a differential element), a phase compensation circuit for stabilizing a natural frequency of a rotating body of several orders, and a static rigidity of a magnetic bearing. Bias current applying circuit for adding,
And so on. These are adjusted and set for each model because the structure, physique, and specifications of the magnetic bearing of the rotating body differ depending on the model of the pump body.

[0006] C of the motor drive circuit 12 differs in the number of revolutions, capacity, output voltage, etc. for each model. Usually, the part 3 for restricting compatibility between these models is incorporated in the power supply device 1 and the position sensor 7, the electromagnet 11, and the motor 1
3 is incorporated in the pump body 2.

[0007]

In general, a turbo molecular pump having a magnetic bearing has a pump body 2 as described above.
And a power supply device 1 having a magnetic bearing control circuit 9 for floating control of the rotating body 4 and a motor drive circuit (eg, an inverter circuit) 12 for directly driving a motor 13 directly connected to the rotating body 4. These two units are connected by a magnetic bearing control cable 31 and a motor drive cable 32.

The power supply device 1 has a portion that is adjusted or set according to the model of the pump body 2. For example, a control circuit (for example, configured by a PID control circuit that is a proportional element, an integral element, and a differential element) for holding the floating position of the rotating body 4 at the center, and a number-order eigenvalue depending on the structure of the rotating body 4 Phase compensation circuit and filter circuit for stabilizing the frequency (for example, notch filter, low-pass notch filter,
These include a low-pass filter, a phase filter, etc.), a bias current application circuit for adding the static rigidity of the magnetic bearing, a compensation circuit for the number of revolutions, a circuit for driving the motor, and the like.

These adjustment values and set values are stored in the pump body 2.
Since the size, size, specifications of magnetic bearings (electromagnets), and specifications of motors differ for each model, each model has a pump main body 2 and a power supply device 1 adapted thereto. For example, in the case of a turbo-molecular pump, if the model (model) is divided according to the pumping speed of the pump, 300 L / s (the pumping speed of the turbo-molecular pump is expressed by a capacity [L] capable of exhausting nitrogen gas or the like in one second [s]. 700 L / s, 120
There are models such as 0 L / s, 2200 L / s, and 3300 L / s, each of which has a dedicated power supply device.

As described above, since the model of the power supply device 1 and the model of the pump main body 2 are in a one-to-one combination, if the combination is changed, the magnetic bearing and the motor lose their proper functions, and stable rotation cannot be performed.

The inability to change the above-described one-to-one combination between models, that is, the incompatibility between the models of the power supply device 1 and the pump main body 2, significantly reduces the mass productivity of the turbo molecular pump. In addition, it is not preferable for management in after-sales service and troubleshooting. Further, when a plurality of types of turbo molecular pumps are used, equipment design of an apparatus or a plant to which the turbo molecular pumps are attached and used becomes complicated, the equipment becomes large, and maintenance becomes difficult.

An object of the present invention is to improve the mass productivity and simplify the after-sales service, and it becomes possible to operate a plurality of types of pump bodies with one kind of power supply device. An object of the present invention is to provide a turbo-molecular pump capable of simplifying the design of an apparatus or a plant, downsizing, and facilitating maintenance.

[0013]

Means for Solving the Problems In order to solve the above problems and achieve the object, a turbo molecular pump of the present invention is configured as follows. The turbo-molecular pump of the present invention, a turbo-molecular pump body comprising a position sensor for detecting the position of the rotating body and a magnetic bearing for holding the rotating body by feedback-controlling the magnetic force by a signal from the position sensor,
A magnetic bearing control circuit and a magnetic bearing drive circuit configured to hold the rotating body at the center position by feedback control using a signal from the position sensor, a motor drive circuit that drives a motor connected to the rotating body, and And a power supply device having a magnetic bearing drive power supply for supplying power to the magnetic bearing drive circuit, wherein a part or all of a circuit for restricting compatibility between models in the power supply device is provided by the turbocharger. It was provided on the molecular pump body side.

As a result of taking the above measures, the following operation occurs. According to the turbo-molecular pump of the present invention, part or all of the circuit that limits compatibility between models in the power supply device is provided on the turbo-molecular pump main body side, so that part or all of the circuit inside the power supply device is provided. Is installed inside or near the turbo molecular pump main body. This allows
Factors limiting the compatibility between the power supply device and the pump body between the models of the turbo molecular pump will be eliminated, and the magnetic bearing and the motor will rotate stably without losing their proper functions. The power supply device and the pump main body can be separately manufactured, and the mass productivity of the turbo molecular pump is improved.

Further, when the power supply unit or the pump main body breaks down, it is only necessary to replace or repair the faulty one, so that the after-service of the turbo molecular pump is simplified. Furthermore, one type of power supply device can operate a plurality of types of pump bodies. When a plurality of types of pump bodies are used, the design of the device or plant is simplified, and the size of the device or plant is reduced. And maintenance is simplified.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) FIG. 1 is a block diagram showing a configuration of a power supply device and a pump main body according to a first embodiment of the present invention. In FIG. 1, the same parts as those in FIG. 6 are denoted by the same reference numerals. In FIG. 1, 1 is a power supply device, and 2 is a pump main body. 8 is a magnetic bearing control circuit, 9 is a magnetic bearing drive circuit, 10 is a magnetic bearing drive power supply,
Reference numeral 12 denotes a motor drive circuit. Also, 7 in the pump body 2 is a position sensor, 11 is an electromagnet, 13 is a motor,
Reference numeral 3 denotes a part that limits compatibility between models. As described above, FIG. 1 shows a part 3 that limits compatibility between models.
Is incorporated in the pump main body 2.

The position sensor 7 of the pump body 2 is
(A) is connected to the magnetic bearing control circuit 8 of the power supply device 1. The magnetic bearing control circuit 8 includes a magnetic bearing drive circuit 9
Is connected to the magnetic bearing drive power supply 10 via the. Also, the magnetic bearing drive circuit 9 is a part 3 (B) of the pump body 2.
And is connected to the electromagnet 11 via. The motor drive circuit 12 of the power supply device 1 is connected to the motor 13 via the portion 3 (C) of the pump body 2.

FIG. 2 is a vertical sectional side view of a turbo-molecular pump to which the power supply device is applied. 2, the same parts as those in FIG. 1 are denoted by the same reference numerals. Based on the output from the position sensor 7, the magnetic force of the electromagnet 11 is controlled by a magnetic bearing control circuit 8 and a magnetic bearing drive circuit 9 having a function of PID and phase compensation, and the rotating body 4 is levitated and held by the magnetic force.

As described above, in the first embodiment, the part 3 which is adjusted or set according to the model of the turbo-molecular pump and limits the compatibility between the models, that is, the magnetic bearing control circuit 8 and the magnetic bearing drive circuit 9 Alternatively, part or all of the motor drive circuit 12 is integrated into the pump body 2 as one unit.

(Second Embodiment) FIG. 3 is a block diagram showing a configuration of a power supply unit and a pump body according to a second embodiment of the present invention. 3, the same parts as those in FIG. 1 are denoted by the same reference numerals. In FIG. 3, 1 is a power supply device, and 2 is a pump main body. Reference numeral 8 in the power supply device 1 denotes a magnetic bearing control circuit, 9 denotes a magnetic bearing drive circuit, 10 denotes a magnetic bearing drive power supply, and 12 denotes a motor drive circuit. Also, 7 in the pump body 2 is a position sensor, 11 is an electromagnet,
13 is a motor. Further, the part 3 restricting the compatibility is separated from the power supply device 1 as one unit 30 and installed outside the pump body 2 and near the pump body 2.

FIG. 4 is a vertical sectional side view of a turbo-molecular pump to which the power supply device is applied. 4, the same parts as those in FIG. 2 are denoted by the same reference numerals. In FIG. 4, the part 3 restricting compatibility is separated from the power supply device 1 and installed outside the pump body 2, and the pump body 2 and the restricting part 3 are connected by cables 31 and 32. ing.
The operation of this turbo molecular pump is the same as that of the turbo molecular pump shown in FIG. 2 in the first embodiment.

The present invention is not limited to the above embodiments, but can be modified as needed without departing from the scope of the invention. For example, the configuration of the present invention can also be applied to a device including a high-speed rotating body having a control magnetic bearing such as a compressor, a turbine, a spindle for a machine tool, a polygon mirror, and the like, and a power supply unit therefor.

(Summary of Embodiment) The configuration, operation and effect shown in the embodiment are summarized as follows. The turbo-molecular pump shown in the embodiment has a position sensor 7 for detecting the position of the rotating body 4 and magnetic bearings 5a and 5b for holding the rotating body 4 by feedback-controlling the magnetic force based on a signal from the position sensor 7. A magnetic bearing control circuit 8 and a magnetic bearing drive circuit 9 configured to hold the rotating body 4 at a center position by feedback control using a signal from the position sensor 7, comprising: A turbo molecular pump comprising: a power supply device 1 having a motor drive circuit 12 for driving a motor 13 connected to the rotating body 4 and a magnetic bearing drive power supply 10 for supplying power to the magnetic bearing drive circuit 9; Power supply 1
A part or all of the circuit 3 for limiting the compatibility between the models is provided on the turbo molecular pump main body 2 side.

As described above, in the turbo molecular pump, a part or all of the circuit 3 for limiting the compatibility between the models in the power supply device 1 is provided on the turbo molecular pump main body 2 side. Part or all of the internal circuit is installed inside or near the turbo molecular pump main body 2. This eliminates the factor that restricts the compatibility between the power supply device 1 and the pump body 2 between the models of the turbo molecular pump, and the magnetic bearings 5a and 5b and the motor 13 The power supply device 1 and the pump main body 2 can be separately manufactured without losing the function of the above, and the mass productivity of the turbo molecular pump is improved.

Further, when the power supply device 1 or the pump main body 2 breaks down, it is only necessary to replace or repair the failed one, so that the after-service of the turbo-molecular pump is simplified. Furthermore, one type of power supply device can operate a plurality of types of pump bodies. When a plurality of types of pump bodies are used, the design of the device or plant is simplified, and the size of the device or plant is reduced. And maintenance is simplified.

[0026]

According to the present invention, the mass productivity can be improved, the after-sales service can be simplified, and a plurality of types of pump bodies can be operated with one type of power supply device.
It is possible to provide a turbo-molecular pump capable of simplifying the design of an apparatus or a plant to which the turbo-molecular pump is attached and used, reducing the size, and simplifying maintenance.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a power supply device and a pump main body according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional side view of a turbo-molecular pump to which the power supply device according to the first embodiment of the present invention is applied.

FIG. 3 is a block diagram showing a configuration of a power supply device and a pump body according to a second embodiment of the present invention.

FIG. 4 is a vertical sectional side view of a turbo-molecular pump to which a power supply device according to a second embodiment of the present invention is applied.

FIG. 5 is a side view showing a configuration of a magnetic bearing portion using an electromagnet as a conventional means for floatingly holding a rotating body.

FIG. 6 is a block diagram showing a control circuit of a conventional magnetic bearing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Power supply device 2 ... Pump body 3 ... Part (circuit) which restricts compatibility between models 4 ... Rotating body 5a, 5b ... Magnetic bearing 6a, 6b ... Position sensor 7 ... Position sensor 8 ... Magnetic bearing control circuit 9 ... Magnetic bearing drive circuit 10 ... Magnetic bearing drive power supply 11 ... Electromagnet 12 ... Motor drive circuit 13 ... Motor 30 ... Unit 31 ... Cable 32 ... Cable

Claims (1)

(57) [Claims] 1. A turbo-molecular pump main body comprising: a position sensor for detecting a position of a rotating body; and a magnetic bearing for holding the rotating body by feedback-controlling a magnetic force based on a signal from the position sensor; A magnetic bearing control circuit and a magnetic bearing drive circuit configured to hold the rotating body at the center position by feedback control using the signal of the above, a motor drive circuit for driving a motor connected to the rotating body, and the magnetic bearing drive circuit And a power supply device having a magnetic bearing drive power supply for supplying power to the turbo molecular pump, wherein part or all of a circuit for limiting compatibility between models in the power supply device is provided on the turbo molecular pump main body side. A turbo-molecular pump characterized by being provided in.