Abstract: A first spacer, a second tubular member, and a second spacer are externally fitted and fixed to an outer peripheral surface of a nut. The second tubular member is formed by stacking a plurality of silicon steel plates without any gap, and is arranged between the first spacer and the second spacer axially. The outer diameter of an outer peripheral surface of the second tubular member is made larger than the outer diameter of an outer peripheral surface of the first spacer and the outer diameter of an outer peripheral surface of the second spacer. A detection surface of a first displacement detector is made to radially face a contact portion between the second spacer and the second tubular member, while a detection surface of a second displacement detector is made to radially face a contact portion between the first spacer and the second tubular member.

Abstract: If the ambient temperature of a pressure volute measured by a temperature sensor exceeds 0° C., a compressor is instantly started at normal operation. If the temperature of the pressure volute measured by the temperature sensor is 0° C. or lower, vibration along the axial direction is given to the rotary shaft by way of an axial magnetic bearing. If the vibration amplitude of the thus given vibration exceeds a predetermined value, the compressor is started at normal operation after idle operation. On the other hand, if the vibration amplitude is lower than a predetermined value, the heater is actuated to heat the pressure volute only for a predetermined time. Thereafter, the ambient temperature is detected again, and if the ambient temperature exceeds 0° C., the compressor is started.

Abstract: A rolling bearing assembly for a wheel includes a cylindrical fixed bearing ring fixed to a vehicle body side, a rotary bearing ring rotatably inserted to inside of the fixed bearing ring, and plural rows of rolling elements rollably arranged between the bearing rings. An annular sensor housing is attached to an inboard side end portion of the fixed bearing ring and includes a plurality of displacement sensors for detecting gaps between the displacement sensors and outer peripheral surfaces of inboard side end portions of the rotary bearing ring in a circumferential direction. Further, an inboard side end portion of the sensor housing is sealed by an inner side seal device.

Abstract: A rolling bearing device with a sensor includes a rotational component estimator that extracts a rotational synchronization component included in the rotation of an inner shaft relative to an outer ring from each of a signal output by a first displacement detector and a signal output by a second displacement detector. The rotational component estimator performs rotational operation and integration operation.

Abstract: A bearing apparatus include a rotor having a flange portion, a foil bearing for supporting the rotor in a radial direction, and a magnetic bearing for supporting the rotor in an axial direction by an electromagnet, and a control portion for controlling electric current supplied to the electromagnet. The control portion controls such that a first electric current is supplied to the electromagnet so as to cause the electromagnet to attract the flange portion so as to support the rotor in the axial direction. The control portion also controls such that when the number of revolutions of the rotor is smaller than the number (R1) of revolutions at which the rotor floats off the foil bearing when supplying the first electric current to the electromagnet, a second electric current larger than the first electric current is supplied to the electromagnet.

Abstract: If the ambient temperature of a pressure volute measured by a temperature sensor exceeds 0° C., a compressor is instantly started at normal operation. If the temperature of the pressure volute measured by the temperature sensor is 0° C. or lower, there is a possibility that a rotary vane may be adhered to the pressure volute due to a congelation. Therefore, vibration along the axial direction is given to the rotary shaft by way of an axial magnetic bearing. If the vibration amplitude of the thus given vibration exceeds a predetermined value, the compressor is started at normal operation after idle operation. On the other hand, if the vibration amplitude is lower than a predetermined value, it is determined that the thus given vibration is unable to eliminate the adhesion of the rotary vane due to the congelation, and the heater is actuated to heat the pressure volute only for a predetermined time. Thereafter, the ambient temperature is detected again, and if the ambient temperature exceeds 0° C.

Abstract: A first spacer, a second tubular member, and a second spacer are externally fitted and fixed to an outer peripheral surface of a nut. The second tubular member is formed by stacking a plurality of silicon steel plates without any gap, and is arranged between the first spacer and the second spacer axially. The outer diameter of an outer peripheral surface of the second tubular member is made larger than the outer diameter of an outer peripheral surface of the first spacer and the outer diameter of an outer peripheral surface of the second spacer. A detection surface of a first displacement detector is made to radially face a contact portion between the second spacer and the second tubular member, while a detection surface of a second displacement detector is made to radially face a contact portion between the first spacer and the second tubular member.

Abstract: A rolling bearing device with a sensor includes a rotational component estimator that extracts a rotational synchronization component included in the rotation of an inner shaft relative to an outer ring from each of a signal output by a first displacement detector and a signal output by a second displacement detector. The rotational component estimator performs rotational operation and integration operation.

Abstract: A rolling bearing assembly for a wheel includes a cylindrical fixed bearing ring fixed to a vehicle body side, a rotary bearing ring rotatably inserted to inside of the fixed bearing ring, and plural rows of rolling elements rollably arranged between the bearing rings. An annular sensor housing is attached to an inboard side end portion of the fixed bearing ring and includes a plurality of displacement sensors for detecting gaps between the displacement sensors and outer peripheral surfaces of inboard side end portions of the rotary bearing ring in a circumferential direction. Further, an inboard side end portion of the sensor housing is sealed by an inner side seal device.

Abstract: A bearing device supporting a rotation shaft of a fuel cell compressor includes a pair of radial foil bearings and mounted in concentric relation to the rotation shaft and supporting the rotation shaft in a radial direction, and an axial magnetic bearing opposed to the rotation shaft in an axial direction and supporting the rotation shaft in the axial direction. A control device includes bearing life diagnostic unit for accumulating times during which a rotational speed of the rotation shaft has been below a predetermined value, so as to obtain a cumulative contact time, thereby judging a bearing lifetime.

Abstract: A fuel-cell compressed-air supplying device 6 includes a centrifugal compressor 12 provided in a casing 11, and a bearing device 14 for supporting a rotation shaft 13 of the compressor 12. The bearing device 14 includes a pair of radial foil bearings 21 and 22 provided coaxially with the rotation shaft 13 for supporting the rotation shaft 13 in the radial direction, and an axial magnetic bearing 23 facing to the rotation shaft 13 in the axial direction for supporting the rotation shaft 13 in the axial direction. Axial electromagnets 24 and 25 of the axial magnetic bearing 23 are integrated with the radial foil bearings 21 and 22, respectively.

Abstract: A fuel-cell compressed-air supplying device 6 includes a centrifugal compressor 12 provided in a casing 11 and a bearing device 14 for supporting a rotation shaft 13 of the compressor 12. The bearing device 14 includes a pair of radial foil bearings 21 and 22 provided coaxially with the rotation shaft 13 for supporting the rotation shaft 13 in the radial direction, a pair of axial foil bearings 23 and 24 facing to the rotation shaft 13 in the axial direction for supporting the rotation shaft 13 in the axial direction, and a secondary bearing means 25 which is constituted by a combination of plural permanent magnets 61a, 61b, 62a, 62b, 63a, 63b, 64a and 64b and holds the rotation shaft 13 in a non-contact manner at static states.

Abstract: A fuel-cell compressed-air supplying device 6 includes a compressor 12 including an impeller 15 provided on one side of a rotation shaft 13 and a turbine 16 provided on the other side of the rotation shaft 13 of the compressor 12. Compressed air is supplied to a fuel-cell stack 2 through the rotation of the impeller 15, and exhaust air exhausted from the fuel-cell stack 2 causes the turbine 16 to rotate.

Abstract: A sensor-equipped rolling bearing assembly includes: a cylindrical fixed bearing ring fixed to a vehicle body; a rotary bearing ring rotatably inserted through the fixed bearing ring and having a wheel-mounting portion on an outboard side thereof; and plural rows of rolling elements rollably interposed between these bearing rings. The bearing assembly is provided with a case member having plural displacement sensors which are circumferentially arranged at predetermined space intervals and which detect gaps between themselves and an outside surface of an inboard end of the rotary bearing ring. The case member is mounted to the inboard end of the fixed bearing ring.

Abstract: A control magnetic bearing device comprises a plurality of control magnetic bearings for contactlessly supporting a rotor, an electric motor for rotating the rotor, a magnetic bearing drive circuit for driving the magnetic bearings, an inverter for driving the electric motor, a main control circuit for controlling the magnetic bearing drive circuit and the inverter, and a power source unit connected to an external power source for supplying electric power to the magnetic bearing drive circuit, the inverter and the main control unit. The main control unit has software-programmable digital processing means for controlling the inverter in accordance with an input voltage value from the power source unit.

Abstract: A control magnetic bearing device comprises a plurality of control magnetic bearings for contactlessly supporting a rotor, an electric motor for rotating the rotor, a magnetic bearing drive circuit for driving the magnetic bearings, an inverter for driving the electric motor, a main control circuit for controlling the magnetic bearing drive circuit and the inverter, and a power source unit connected to an external power source for supplying electric power to the magnetic bearing drive circuit, the inverter and the main control unit. The main control unit has software-programmable digital processing means for controlling the inverter in accordance with an input voltage value from the power source unit.

Abstract: A control magnetic bearing device comprises a plurality of control magnetic bearings for contactlessly supporting a rotor, an electric motor for rotating the rotor, a magnetic bearing drive circuit for driving the magnetic bearings, an inverter for driving the electric motor, a main control circuit for controlling the magnetic bearing drive circuit and the inverter, and a power source unit connected to an external power source for supplying electric power to the magnetic bearing drive circuit, the inverter and the main control unit. The main control unit has software-programmable digital processing means for controlling the inverter in accordance with an input voltage value from the power source unit.

Abstract: A rolling element in a stationary state as surrounded by magnetic bearings is moved until it abuts against a protective bearing, and thereby a mean value of movement spans S is determined. A machine type is determined based on a fact that the mean value of movement spans varies depending upon the types of machine bodies, and then the setting of control parameters is made. In this manner, a control unit of the magnetic bearing is adapted for multiple types of machine bodies.

Abstract: A magnetic bearing device includes a pair of electromagnets holding a rotary body at opposite sides thereof in the direction of each of control axes, a detector for detecting the position of the rotary body, and an electromagnet controller having an integral operation unit for controlling the electromagnets based on the result of detection of the position. The electromagnet controller sets as a target levitated position of the rotary body the position of the rotary body corresponding to the median of an integral output of the integral operation unit when the rotary body is magnetically levitated in the vicinity of one of limit positions in the direction of the control axis determined by protective bearings and an integral output of the unit when the rotary body is magnetically levitated in the vicinity of the other limit position.

Abstract: In a control unit for magnetic bearing, a sampling frequency of a DSP 4 is varied according to a number of rotation of a rolling element 1. Thus, a frequency band to be damped by a notch filter 42 as a digital filter is varied in correspondence with a resonance frequency associated with a natural frequency and a rotational vibration frequency, thereby to damp a resonance signal contained in a control signal. The occurrence of resonance is thus prevented through digital control.