Shimadzu Corporation

Junichiro Kozaki

Yoshihiro Nagano

Masaki Ohfuji

Masaya Nakamura

Nobuyuki Hirata

Atsuo Nakatani

Nobuhiko Moriyama

Yoshio Tsunazawa

Akira Arakawa

Masaki Ofuji

Toshiki Yamaguchi

Takuto Onishi

An estimation device for estimating a process gas condition in a system for pumping gas from a vacuum chamber into which the gas is injected to perform a treatment process by a vacuum pump attached to the vacuum chamber through a vacuum valve, comprises: a computer having a processor and a memory, wherein the computer estimates a first process gas condition including an injected gas type and a gas flow rate based on correlation data between a valve body opening degree of the vacuum valve and an effective exhaust speed of the system regarding a predetermined gas type and a chamber pressure of the vacuum chamber.

Estimation device, vacuum valve, and vacuum pump

An estimator comprises: an acquisitor to acquire a plurality of data pairs each containing a valve body opening of the vacuum valve and the chamber pressure at the valve body opening; and an operator to operate the gas species characteristic value and the first chamber volume estimation value, based on an exhaust's expression representing a relationship among the second effective exhaust rate, a flow rate of a gas introduced into the vacuum chamber, a chamber volume, and a chamber pressure, the plurality of data pairs acquired in the acquisitor, and correlation data between the valve body opening and the second effective exhaust rate about the predetermined known gas.

Estimator and vacuum valve

A controller includes an opening degree control section configured to control a valve element opening degree of the valve main body based on a pressure measurement value of the vacuum chamber measured by a vacuum meter, and an estimation section configured to estimate measurement lag information of pressure measurement value with respect to a pressure of the vacuum chamber based on (a) an exhaust expression including a second-order derivative term of the pressure measurement value and indicating a relationship between an effective exhaust speed of a vacuum pumping system for the vacuum chamber and the pressure measurement value and (b) a pressure measurement value measured during a pressure response when the valve element opening degree is step-changed, and the opening degree control section controls the valve element opening degree based on the measurement lag information estimated by the estimation section.

Vacuum valve, method of controlling vacuum valve, and estimation device

An estimation device comprises: an oscillation section configured to superimpose an oscillation signal for oscillating a valve body of a vacuum valve provided between a vacuum pump configured to pump gas from a chamber and the chamber on an opening degree signal for driving the valve body; and an estimation section configured to estimate, based on a pressure response of a chamber internal pressure upon oscillation, a pumping characteristic regarding the gas pumped through the vacuum valve.

Estimation device and valve control device

A valve control apparatus comprises: a generator configured to generate a first set pressure signal; and a valve opening controller configured to perform the first valve opening control on the basis of the target pressure and, after the first valve opening control, perform the second valve opening control performing feedback control on the basis of a difference between the first set pressure signal and the chamber pressure. The generator generates the first set pressure signal on the basis of a first set pressure locus converging from the chamber pressure at the time of switching from the first valve opening control to the second valve opening control to the target pressure with a predetermined time constant.

Valve control apparatus and vacuum valve

A vacuum valve for driving a valve body arranged facing a valve opening up and down relative to the valve opening to perform valve opening/closing operation, comprises: a first up-down driver configured to drive the valve body up and down with a first minimum drivable amount; and a second up-down driver configured to drive the valve body up and down with a second minimum drivable amount smaller than the first minimum drivable amount.

Vacuum valve and valve control device

A magnetic levitation control device comprises: a control signal generation section configured to generate a first excitation current control signal based on current deviation information on the excitation current detection signal with respect to the current setting signal and a second excitation current control signal based on the current setting signal; and a selection section including a first switching section configured to select either one of the first excitation current control signal or the second excitation current control signal or a second switching section configured to select either one of a third excitation current control signal obtained by summation of the first excitation current control signal and the second excitation current control signal or the second excitation current control signal. The excitation amplifier is PWM-controlled based on the excitation current control signal selected by the selection section.

Magnetic levitation control device and vacuum pump

A first arithmetic section calculates a current rotation component phase value and a current rotation component amplitude value. A second arithmetic section calculates a displacement rotation component phase value and a displacement rotation component amplitude value. A third arithmetic section calculates a ratio between the amplitude value of the current rotation frequency component and the amplitude value of the displacement rotation frequency component. Feedback control is performed such that the current rotation component phase value is equal to a value obtained by addition of a phase value of 180 degrees to the displacement rotation component phase value and that the amplitude value of the current rotation frequency component is equal to a product of the displacement rotation frequency component and the ratio.

Magnetic bearing control device and vacuum pump

A vacuum pump includes; a rotor, a stator, a motor, a heating section heating the pump base portion, a base temperature detection section detecting a temperature of the pump base portion, a rotor temperature detection section detecting a temperature equivalent as a physical amount equivalent to a temperature of the rotor, and a heating control section to control heating of the pump base portion by the heating section such that a detection value of the rotor temperature detection section falls within a predetermined target value range. A monitoring device comprises: an estimation section configured to estimate, based on multiple temperatures detected over time by the base temperature detection section, maintenance timing at which the temperature of the pump base portion reaches equal to or lower than a predetermined temperature; and an output section configured to output maintenance information based on the estimated maintenance timing.

Monitoring device and vacuum pump

A target opening degree estimator estimates a target opening degree estimation value as an opening degree of a valve element of a pressure adjustment vacuum valve when a pressure of a vacuum chamber connected to the pressure adjustment vacuum valve reaches a pressure adjustment target pressure based on a correlation between the opening degree of the valve element and the pressure of the vacuum chamber, a current opening degree, and a current pressure.

Target opening degree estimator and pressure adjustment vacuum valve

A magnetic bearing device comprises a radial magnetic bearing configured to magnetically levitate and support a rotor shaft in a radial direction; an axial magnetic bearing configured to magnetically levitate and support, in an axial direction, a rotor disc rotatable together with the rotor shaft; and an axial displacement sensor disposed on a surface of an electromagnet core of the axial magnetic bearing facing the rotor disc and configured to detect axial displacement of the rotor disc.

Magnetic bearing device and vacuum pump

A vacuum valve connected to a vacuum pump, comprises: a valve plate to be openably/closably driven; a drive section configured to openably/closably drive the valve plate; a signal input section to which a pump information signal indicating an operation state of the vacuum pump is input; and a valve control section configured to control operation of the valve plate based on the input pump information signal.

Vacuum valve, vacuum pump, and vacuum pumping system

A magnetic bearing vacuum pump comprises: a first displacement signal generation section configured to amplify, by a resolution multiplying factor K of K&#x3e;1, a displacement modulated wave signal modulated according to a displacement of the rotor from a predetermined position to generate a high-resolution displacement signal in a first displacement region including the predetermined position; a second displacement signal generation section configured to generate a low-resolution displacement signal in a larger second displacement region including the first displacement region; a selection section configured to select either one of the high-resolution displacement signal or the low-resolution displacement signal based on an unsteady-state response signal obtained by excluding a steady-state whirling displacement component from the high-resolution displacement signal or the low-resolution displacement signal; and a bearing control section configured to control the magnetic bearing based on the displacement signal selected by the selection section.

Magnetic levitation vacuum pump

A magnetic bearing control device is configured to detect, by a sensor, excitation current supplied from an excitation amplifier to a magnetic bearing configured to magnetically levitate a rotor, thereby generating a voltage equivalent signal for PWM control of the excitation amplifier based on a current setting signal based on a deviation of a rotor levitation position with respect to a target levitation position and an excitation current detection signal of the sensor. The voltage equivalent signal is generated based on the current setting signal and a current deviation signal as a difference between the current setting signal and the excitation current detection signal.

A valve control device configured such that a pressure measurement value of a chamber, a target pressure value of the chamber, and an opening degree measurement value of the vacuum valve are input to the valve control device and configured to control an opening degree of the vacuum valve based on a deviation between the pressure measurement value and the target pressure value, comprises: a storage storing a correlation between the opening degree of the vacuum valve and a conductance of a system including the vacuum valve; and a correction gain setting section obtaining, based on the correlation, a change rate of the conductance in association with an opening degree change at the input opening degree measurement value, thereby setting an inverse of the change rate as a correction gain. The opening degree of the vacuum valve is controlled based on the deviation and the correction gain.

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Kyoto, Japan

Junichiro Kozaki