Ebara Corporation

Other

Komatsu Corporation

Toshimitsu Barada

Toshiharu Nakazawa

Shinichi Sekiguchi

Hiroyuki Shinozaki

Atsushi Ooyama

Toshiya Yoshida

Tomonori Ohashi

Ichiju Sato

Satoshi Mori

Masafumi Inoue

Hiroyuki Kawasaki

Takeshi Kawamura

Hiroshi Sobukawa

Natsushi Suzuki

Shunichi Aiyoshizawa

Ichiju Satoh

Hironobu Yamasaki

Shunsuke Yoshioka

Hisashi Nara

Masakazu Komai

Atushi Ooyama

Yu Kakesu

Kunihiko Tanaka

Misako Kudo

A magnetic bearing apparatus capable of correcting inclination of a rotating element with a small magnetic attractive force and capable of stably supporting the rotating element is disclosed. The magnetic bearing apparatus includes: a non-magnetic ring made of non-magnetic material; and at least three axial magnetic poles arranged along a circumferential direction of the non-magnetic ring. Each axial magnetic pole has an arc-shaped coil and a coil housing that accommodates the coil therein. The at least three axial magnetic poles are fixed to the non-magnetic ring.

Magnetic bearing apparatus with axial pole segments

An advanced substrate rotation device is provided. A substrate rotation device is disclosed. The substrate rotation device includes an outer cylinder, an inner cylinder positioned inside the outer cylinder, a motor for rotating the inner cylinder, a magnetic bearing for magnetically levitating the inner cylinder, and a substrate holder disposed on the inner cylinder. The motor is a radial motor including a motor stator mounted on the outer cylinder, and a motor rotor mounted on the inner cylinder. The magnetic bearing is a radial magnetic bearing including a magnetic bearing stator mounted on the outer cylinder, and a magnetic bearing rotor mounted on the inner cylinder. The magnetic bearing is configured to magnetically levitate the inner cylinder with an attractive force between the magnetic bearing stator and the magnetic bearing rotor.

Substrate rotation device, substrate cleaning device, substrate processing device, and control method for substrate rotation device

The electromagnet device of the present invention comprises: a yoke having an annular groove in a front surface thereof; an annular coil provided in the groove; and an epoxy resin provided on an outer surface of the coil configured to secure the coil to the yoke, wherein there is a clearance between an outer circumferential surface of the groove in the yoke and the epoxy resin provided on an radially outer side of the coil.

Electromagnet device, electromagnet controller, electromagnet control method, and electromagnet system

A magnetic levitated pump that does not cause pulsation of a pumped liquid and can suppress the generation of particles, which are liable to be produced by contact of a sliding part, is disclosed. The magnetic levitated pump for magnetically levitating an impeller housed in a pump casing includes a motor configured to rotate the impeller, and an electromagnet configured to magnetically support the impeller. The motor and the electromagnet are arranged so as to face each other across the impeller, and the motor is arranged on the opposite side of a suction port of the pump casing.

Magnetic levitated pump

A magnetic bearing apparatus for supporting a rotational shaft includes a magnetic bearing, a rotation sensor, a controller which controls an electric current flown to an electromagnet, and at least one vibration sensor. The controller controls the electric current flown to the electromagnet as follows: in a first control mode, a first electric current is flown to the electromagnet for levitating and supporting the rotational shaft; and in a second control mode, a second electric current is flown to the electromagnet in place of the first electric current at a first periodic timing which is detected by the rotation sensor so that vibration is reduced to a lower level than a first vibration value detected in the first control mode in at least one of setting location of the at least one vibration sensor.

Magnetic bearing apparatus and method for reducing vibration caused by magnetic bearing apparatus

An oil-free turbo vacuum pump is capable of evacuating gas in a chamber from atmospheric pressure to high vacuum. The turbo vacuum pump includes a pumping section having rotor blades and stator blades which are disposed alternately in a casing, and a main shaft for supporting the rotor blades. A gas bearing is used as a bearing for supporting the main shaft in a thrust direction, spiral grooves are formed in both surfaces of a stationary part of the gas bearing, and the stationary part having the spiral grooves is placed between an upper rotating part and a lower rotating part which are fixed to the main shaft. A thrust magnetic bearing for canceling out a thrust force generated by the differential pressure between a discharge side and an intake side by an evacuation action of the pumping suction is provided.

Turbo vacuum pump

An energy-saving magnetic bearing device with no bias current for making the relation between the excitation current and the magnetic force of the electromagnet linear is provided. In a magnetic bearing device for supporting a rotorserving as the magnetic piece in a levitating state allowing free rotation at a specified position by the magnetic force of a pair of electromagnets, the electromagnetsare constituted to interpose the rotorand face each other. A driveris a PWM (pulse width modulation) type driver for controlling the excitation current in the electromagnetsby modulating the pulse width of a voltage driven at a specified carrier frequency fc, and includes a resonator means for electrically resonating at a frequency equal to the carrier frequency fc. When an excitation current flows in either one of the pair of opposing electromagnets, then the other magnet is regulated so that the DC component in the electromagnet excitation current is zero, and a voltage is applied via the resonator means to the electromagnet whose DC component in the excitation current is discharged to zero.

Magnetic bearing device and method

A magnetic bearing apparatus supports a rotating object using magnetic levitation by a magnetic force of electromagnets. The magnetic bearing apparatus includes a PWM driver configured to supply exciting currents to the electromagnets, a driver power source configured to drive the PWM driver, and a displacement error signal removing section configured to extract a displacement error signal of the displacement information from a current flowing through the driver power source and to remove the displacement error signal from the displacement information.

Magnetic bearing apparatus

A magnetic bearing apparatus has an electromagnet having a coil for levitating a rotatable member by a magnetic force and a control device to adjust a gain for levitation control of the rotatable member. The control device includes a displacement sensor to detect a levitated position of the rotatable member, a driver to supply a current to the electromagnet, and a phase compensator to adjust the current based on a signal from the displacement sensor. The control device also includes a band-pass filter into which an output signal of the phase compensator is inputted, an amplifier to amplify an output signal of the band-pass filter at a predetermined amplification ratio, and an adder to add an output signal of the amplifier to an output signal of the phase compensator and supply an added signal to the driver. The band-pass filter has a center frequency based on an actual rotation frequency of the rotatable member, a voltage, a current, or a frequency of a power source for a motor.

An excimer laser apparatus in which deterioration of the laser gas in the laser container can be suppressed, and damage to the magnetic bearings caused by the laser gas can be suppressed, and which can be reduced in size and operated efficiently, and has low power consumption. Each electromagnet (stator) ( - ) of a magnetic bearing ( ) for supporting a rotary shaft ( ) of a circulation fan includes excitation coils. Each of the coils is arranged as one unit by embedding a coil body in a ceramic or glass type hardened material which is non-magnetic and has corrosion resistance against a laser gas. The excitation coils are attached to magnetic poles. Alternatively, coil wires ( ) of a radial magnetic bearing ( ) can be isolated from a corrosive atmosphere by means of a separation wall ( ) while projecting portions of cores ( ) extend through the separation wall ( ) and are exposed toward a magnetic bearing rotor ( ).

Excimer laser apparatus

There is provided an electric discharge gas laser comprising a housing, a rotating fan, a bearing device and a control. The housing contains a laser gas. The rotating fan is provided in the housing to circulate the gas in the housing. The bearing device magnetically supports a rotating shaft. The bearing device is provided with a sensor device comprising a sensor and a signal processor. The sensor senses the position of the rotating shaft to generate signals indicating the position of the rotating shaft. The signal processor receives and processes the signals delivered from the sensor to output processed signals. The control is separated from the bearing device and is functionally associated with the bearing device to receive the processed signal from the sensor device for controlling the bearing device on the basis of the processed signals.

Electric discharge gas laser

A discharge-pumped excimer laser device has a casing, a pair main discharge electrodes, a cross-flow fan for producing a high-speed laser gas flow between the main discharge electrodes, the cross-flow fan having a rotatable shaft projecting from opposite ends thereof, magnetic bearings, the rotatable shaft being rotatably supported by the bearings, protective bearings for supporting the rotatable shaft when the magnetic bearings are not in operation, and a motor for actuating the cross-flow fan. The magnetic bearings include radial magnetic bearings disposed on the opposite ends of the rotatable shaft. One of the radial magnetic bearings which is disposed closely to the motor has a bearing rigidity greater than the bearing rigidity of the magnetic bearing that is disposed remotely from the motor.

Discharge-pumped excimer laser device

A magnetic bearing enables to rotatably support a levitated body non-contactingly disposed in a hermetically sealed container filled with a gaseous process substance of a corrosive nature, while without contaminating the gaseous environment and suffering from corrosion. The magnetic bearing has an electromagnet for supporting a levitated body, a displacement sensor for detecting a levitated position of the levitated body, and a controller for supplying signals and excitation currents to the displacement sensor and the electromagnet through cables. An electromagnet target of the magnetic bearing that generates variations in magnetic fields due to rotation of the levitated body, is constructed of a single piece of ferromagnetic material, and is provided with an electrical insulation structure oriented parallel to magnetic fluxes generated by the electromagnet.

Growing community of inventors

Tokyo, Japan

Toshimitsu Barada