A vacuum pump and a control device are capable of accurately determining timing of rotor blade replacement by creating an index which allows a degree of fatigue of a rotor blade to be determined quantitatively and easily. A motor current value output from a motor drive control portion is input to a time count processing portion, and time in which a current value of a rotating body remains in a range of a stage is totalized for each stage of the current value in the time count processing portion. A rotor blade temperature value output from a rotor blade temperature measurement portion is also input to the time count processing portion. A one-minute average value of the rotor blade temperature value acquired by sampling is calculated. For each stage of the rotor blade temperature value, time in which the average value remains in a range of the stage is totalized.

A vacuum pump capable of improving cleaning performance is provided. A heater, purge gas introduction ports, a purge gas valve, and an exhaust valve are provided. As an operation mode, a cleaning operation mode capable of sublimating deposits in a turbomolecular pump is provided. In the cleaning operation mode, at least one of the heater, the purge gas valve, and the exhaust valve is controlled, and a pressure in at least a part of an interior of the turbomolecular pump is increased to a pressure region with which a temperature is greater than or equal to a sublimation temperature of the deposits in the turbomolecular pump and that causes an intermediate flow or a viscous flow.

A vacuum pump for rotary driving a rotor by a motor to perform vacuum pumping, wherein a motor rotor of the motor includes a yoke fixed to a shaft of the rotor, and a permanent magnet held at the yoke, and the yoke includes a holding portion provided apart from the shaft and configured to hold the permanent magnet, and a pair of fitting portions provided respectively at both ends of the holding portion in an axial direction and bonded to the shaft by fitting, and a radial thickness dimension of each fitting portion is set less than that of the holding portion.

A vacuum valve attached to a vacuum pump configured to generate regenerative power to perform a stop operation upon blackout, comprises: a first power input section to which power is input from a commercial power source; a second power input section to which the regenerative power generated at the vacuum pump is input; and a valve source circuit to which the power input to each of the first and second power input sections is supplied. When the power from the commercial power source is supplied to the first power input section, the vacuum valve is operated by the supplied power, and when the power from the commercial power source is stopped, the vacuum valve is operated by the regenerative power.

A vacuum pump includes: a casing formed with an inlet port or outlet port; a stator disposed inside the casing; and a rotor enclosed in the casing and including a shaft rotatably supported on the stator, and a rotor blade formed in a cylindrical shape with a plurality of blades arranged in multiple stages on an outer circumferential portion thereof, and secured to the shaft such as to be integrally rotatable therewith. The rotor blade is provided with a rupture location control groove as a rupture location control means that locally reduces rigidity of the rotor blade to control a location where the rotor blade ruptures.

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.

A vacuum pump, and a waterproof structure and a control apparatus applied to the vacuum pump which improve efficiency of on-site maintenance work and prevent water from penetrating into a connector connecting portion when a cover is removed during circuit separation or the like. When performing maintenance work, after a chassis of a control apparatus is lowered by around several tens of millimeters, the chassis of the control apparatus is pulled out in a radial direction of a pump. Accordingly, a pump main body and the control apparatus can be readily attached and detached even when sufficient empty space is not available in an axial direction of the vacuum pump. A wall portion is circumferentially protrusively provided in side portions of the base portion and the control apparatus. Furthermore, a sealing member and a lid are inserted into a gap. Therefore, water droplets cannot easily penetrate into the gap.

The present invention is directed to a magnet for a magnetic bearing arrangement, a bearing arrangement comprising said magnet, and a vacuum pump comprising said bearing arrangement. In particular the invention can be particularly useful in a magnetic bearing arrangement that reduces stray magnetic fields for a turbomolecular vacuum pump, although it is understood that the invention is not limited to this field and other applications will be understood by the skilled person.

A vacuum pump includes: a rotor that is rotated to perform evacuation; a pump disassembly detection circuit that detects a disassembled state in which the vacuum pump is disassembled; and a pump operation prohibition circuit that prohibits rotary drive of the rotor when the pump operation prohibition circuit determines that the pump disassembly detection circuit has detected the disassembled state.

A magnetic bearing device includes a magnetic bearing including a plurality of electromagnets, a displacement sensor configured to output an output signal in accordance with a displacement of a shaft, and a controller configured to control the electromagnets. The controller compensates for a change in levels of the output signal, the change occurring in accordance with a change in ambient temperature around the displacement sensor, based on one or more reference values correlating with the change in levels of the output signal. The one or more reference values are detected for use in controlling the rotary electric machine, a fluid machine system including the rotary electric machine, or an apparatus including the fluid machine system.