摘要:
A magnetic hearing device and a method of operation for such a device are provided. The device comprises a group (410) of electromagnetic actuators (411, 412, 413, 414). Each actuator is electrically connected to an amplifier unit (701). The actuators of a first subgroup are connected to a first common node (608), while the actuators of a second subgroup are connected to a second common node (609). The common nodes (608, 609) are connected either directly or through means like an additional actuator. Preferably the common nodes (608, 609) have no additional electrical connection to the amplifier unit. According to a special embodiment of the invention, each subgroup of actuators consists of only one single actuator and the common node has an electrical connection to the amplifier. Thus the device comprises two actuators in a series configuration connected to an H bridge. The common node may be connected to either of two different voltages. The invention enables simplified wiring without increased load requirements for the wires.
摘要:
A magnetic suspension bearing includes a plurality of magnets enclosed in an outer and an inner enclosure respectively. These magnets are disposed staggeringly up and down remaining a gap between each pair of magnets so as to generate a magnetic suspension force produced form repulsion force between magnets of the same polarity. With this magnetic suspension bearing the shaft is able to rotate with high speed yet less generation of heat loss by friction to improve the durability of the bearing compared with a conventional pivot or ball baring.
摘要:
The invention relates to an inertial sensor based on the magnetic levitation of an inertial mass comprising an active magnetic bearing unit arranged in such a way as to levitate the inertial mass and characterized by the fact that it furthermore comprises additional active magnetic bearings units arranged in such a way as to control the position of said inertial mass along three independent axis and to create, for any of said independent axis, restoring forces that can be oriented in any of the two directions of said independent axis.
摘要:
A magnetic bearing device is provided which is capable of reducing vibration, as well as electric and magnetic noise, generated from a pump device while making it possible to control the position of a rotor at high speed and high power. Also provided is a pump device having the magnetic bearing device mounted thereto. Switching is made between a high-voltage mode in which an electromagnet coil is supplied with electric power from a high voltage power source and a low voltage mode in which the electromagnet coil is supplied with electric power from a low voltage power source. The switching is made based on whether or not a current change speed is below a reference current change speed. When the current change speed is equal to or larger than the reference current change speed, the device is switched to the high voltage mode. When the current change speed is less than the reference current change speed, the device is switched to the low voltage mode.
摘要:
This invention is directed to the prevention of the deterioration of the accuracy in component mounting by suppressing the temperature rise of the moving member as much as possible by cooling the moving member, which is the heat source of a linear motor. The moving member 48 of the linear motor 14 is configured in the following manner for achieving the objective of this invention. That is, the heat dissipation portion, the axis 17 made of the material with efficient thermal conduction such as aluminum, pierces through the iron core 18 around which coils 20 are wound. The moving member except a part of the axis 17 is molded with synthetic resin, and at one end of the axis 17, the heat dissipation fin 19 which makes heat dissipation area larger is formed. And this heat dissipation fin 19 is placed to face the air exhaust port 67. By configuring the moving member in aforementioned manner, the temperature rise is suppressed even if the coils 20 generate heat, because the heat in the coils 20 is transmitted to the iron core 18 and then to the axis 17 and dissipated through the heat dissipation fin 19. The heat in the outermost part of the iron core 18 from the heat dissipation fin 19 is also transmitted to the heat dissipation fin 19 through the axis 17 resulting in the suppression of the temperature rise of the moving member as a whole.
摘要:
An electro-mechanical battery having an annular rotor structure with magnetic levitation components integrally mounted in the rotor structure providing a passive levitation system in conjunction with a central core having permanent magnet elements mounted thereon, eliminating the need for the shaft and hub typically used on such devices. The rotor structure and central core are disposed in an evacuated housing. The rotor comprises a composite core wrapped with one or more layers of high-strength composite filaments, wherein the first layer is wrapped over the composite core in a continuous filament spiral-wound pattern, the second layer is wound in the same pattern, but in a counter-rotating direction and the third layer is wound in sequential planes radial to the axis of the rotor. Preferably, the closed-circuit conductive coils are embedded in the rotor structure and the magnet elements are configured in a Halbach Array.
摘要:
An apparatus for demonstrating, investigating and observing Brownian motion and temperature of a medium, such as gas or liquid, uses a small particle which is diamagnetically suspended in the medium. The tiny magnetized particle having a known mass is levitated using a diamagnetic technique, and the displacement of the particle over time is observable, which can be used to determine a temperature of the medium. Optionally, a second particle is suspended in a vacuum but mechanically connected to the same apparatus as the first enclosure with the first particle, thereby allowing observation and measurement of non-Brownian movement of the structure, and allowing more precise observation of Brownian movement effects on the first suspended particle.
摘要:
The present invention provides a low vibration brushless motor for reducing the vibration of the motor in an axial direction. In the brushless motor, a bearing is provided in a bearing boss, a shaft is held by the bearing, an end face of the shaft is contacting a thrust receiving member, and the shaft is rotatably axially supported by the bearing. The brushless motor includes a permanent magnet for attracting the end face of the shaft in the thrust direction with the thrust receiving member therebetween, and a bottom receiving part for supporting the permanent magnet, wherein the bearing boss, bearing, shaft, and bottom receiving part are made of a magnetic material, and a closed magnetic path is formed so that a magnetic flux passes through the permanent magnet, bottom receiving part, bearing boss, bearing, and shaft.
摘要:
The flux densities formed by plural electromagnet poles M1 to M12 which are arranged at a predetermined interval in a circumferential direction of a rotary body 1 at the same position in an axial direction of the rotary body 1 are gradually changed in the circumferential direction of the rotary body. Even if there is a difference between the maximum value of the flux density and the minimum value, the change of the flux densities between the adjacent electromagnet poles is small and smooth. Accordingly satisfactory detective sensitivity and detection results can be obtained.
摘要:
A magnetic bearing system allows a movable body to be positioned to a point of substantial equilibrium in an axial direction after a system shutdown. A sensor measures the axial position of the movable body to produce an displacement output. That output is then adjusted to account for a sensor offset. The adjustment is stored and can be used to position the movable body during regular operation of the system or when the system reboots or restarts. The adjusted displacement output is converted into a force for positioning the movable body. The movable body may be a rotor in a heart pump apparatus.