2008results about "Magnetic holding devices" patented technology

The invention disclosed is a method of levitating one or both ends of an object permanently or temporarily, or altering the distance between two objects or the momentum of an object by manipulating the direction of the magnetic field of a permanent or electromagnet.

This invention relates to a three freedom degree AC-DC radial-axial mixing magnetic bearing, which is fit for the electrical main shaft and rotary main shaft needs suspending support. The permanent magnet will provide radial-axial static bias magnetic flux to generate static bearing ability; the radial controlling coil and the axial controlling coil will provide magnetic flux to generate dynamic suspending force, making the rotor suspending on the balance place in radial-axial three freedom degree. The power enlarging circuit comprises axial liner power amplifier and radial CRPWM current tracking inverter, and the displacement sensor will test the shift of the rotor and then feedback to DSP controller; the DSP will operate PID compute and process, provide controlling signal to power enlarging circuit; the controlling signal will generate controlling current in magnetic bearing coil, and the controlling current will generate magnetic force in operation magnet, by which it can realize the stable suspending and real-time monitoring of the rotor in radial and axial.

The invention can let magnetic suspended body to suspend above the foundation and rotate horizontally. It includes a magnetic foundation and a suspended permanently magnetic body whose gravitational energy can balance the magnetic repulsion between the foundation and the suspended magnetic body to make it suspend at a preset reference position above the foundation. The foundation includes: a permanently magnetic ring or multi permanent magnets arranged into a ring, which are horizontally located in the foundation and has opposite polarity on its upper surface to the one on the bottom of suspended magnetic body; and a controller located in the foundation for use in maintaining the suspended magnetic body in the preset reference position. The invention can be used in toy.

A lithographic projection apparatus includes a passive magnetic bearing configured to provide support between a first and second part of the lithographic apparatus and allow both parts to be displaced relative to each other in a direction perpendicular to the support direction. The passive magnetic bearing includes first and second magnetic assemblies. Each magnetic assembly includes at least one permanent magnet.

The present invention relates to a magnetic suspension reaction flywheel open-loop high-accuracy unbalanced vibration control system. It includes the following several portions: displacement sensor, displacement signal interface circuit, rotating speed detection device, magnetic bearing controller, magnetic bearing power amplification drive circuit and flywheel position identification device. The magnetic bearing controller includes axial bearing controller and radial bearing controller, the radial bearing controller is formed from two portions of stabilization controller and unbalanced vibration controller, in which the unbalanced vibration controller can be used for making compensation for displacement feedback of stabilization controller.

Servo controlled solenoids provide actuation of a pump piston and valves, and electronic LC resonance measurements to determine liquid volume and gas bubble volume. Third order nonlinear servo control is split into nested control loops: a fast nonlinear first-order inner loop causing flux to track a target by varying a voltage output, and a slower almost linear second-order outer loop causing magnetic gap to track a target by controlling the flux target or the inner loop. The inner loop uses efficient switching regulation, preferably based on controlled feedback instabilities, to control voltage output. The outer loop achieves damping and accurate convergence using proportional, time-integral, and time-derivative gain terms. The time-integral feedback may be based on measured and target solenoid drive currents, adjusting the magnetic gap for force balance at the target current.

A magnetic levitation system for supporting an object against gravity by a supporting force includes a permanent-magnet dipole aligned in a vertical position and coupled to the object, a supporting-field generator and a stabilization system. The supporting-field generator generates a supporting force on the permanent-magnet dipole via a supporting field. The supporting field is a two-dimensional or three-dimensional magnetic quadrupole field so that the supporting force is independent of a position of the dipole. The stabilization system constrains the dipole against movements in at least one horizontal direction, and includes a diamagnetic element coupled to the dipole and arranged below the dipole, and a stabilizing-field generator generating a second two-dimensional or three-dimensional stabilizing field to restore said diamagnetic element to a position where the field strength of the stabilizing field has a local minimum.

A remote controlled inspection vehicle provides interchangeable modules, permitting the vehicle to be easily configured to perform a wide variety of tasks. The vehicle includes at least one frame module having a pair of drive modules on either side. Each drive module includes a continuous track surrounding a permanent magnet, and is dimensioned and configured to pivot around its longitudinal axis. The frame modules are dimensioned and configured to be hingedly secured to other frame modules, end effectors including various sensors for performing inspections, and tail units to assist in placing the vehicle in the desired environment.

A multi-DOF system including a bearing for centering a first body relative a second body, and a work piece surface tiltable via the first body, wherein the bearing comprises a magnetically levitated bearing.

The invention discloses an energy storage device of magnetic suspension flywheel, comprising an energy storing and converting part, a magnetic suspension supporting part and an auxiliary part, wherein the energy storing and converting part includes a flywheel, a rotor of the motor/generator and a stator part; the magnetic suspension supporting part comprises a radial magnetic bearing, an axial magnetic bearing, an axial sensor, a radial sensor and a protection bearing; the auxiliary part includes a shell and a mounting shaft; the radial magnetic bearing is a radial mixed conical magnetic bearing; the suction disk of each axial magnetic bearing is respectively installed on two side wheel surfaces of the flywheel; the radial mixed conical magnetic bearing and the axial magnetic bearing are non-mechanically contacted magnetic suspension bearings; the mounting shafts of the energy storing and converting part, the magnetic suspension supporting part and the auxiliary part are sealed in the shell of the auxiliary part; the inside of the shell is in vacuum state. The invention has the characteristics of compact structure, high specific energy density and discharge depth, long service life, low power consumption and stable performance without pollution.

Disclosed a high speed magnetic levitation flywheel stability control system, comprises a displacement sensor, a displacement signal interface circuit, a rotary speed detect circuit, a magnetic bearing controller, and a magnetic bearing power amplifying drive circuit. Wherein, the magnetic bearing controller comprises a axial magnetic bearing controller and a radial magnetic bearing controller, while the radial one is formed by decentralized PID control module and a cross feedback control module whose outputs are connected by the feedback method in cross and parallel. Said invention utilizes the cross feedback control formed by forward whirling motion filter and backward whirling motion filter based on the decentralized PID control; it reaches the phase lead compensation to the forward and backward whirling motion by using the difference of their frequency and whirling motion directions, their variation rule of rotary speed, and the signal of rotary speed of flywheel. So the breakdown speed of flywheel is improved while the stable operation of magnetic levitation flywheel in whole rising and falling process is confirmed too.

The invention relates to a silicon slice platform multi-platform exchange system adopting a magnetic levitation planar motor, which is mainly used in a lithography machine system. The silicon slice platform multi-platform exchange system comprises a base platform, a silicon slice platform group and a silicon slice platform driving device, wherein, the silicon slice platform group comprises a plurality of silicon slice platforms which have the same structure and are respectively worked in pretreatment working positions or exposure working positions, the silicon slice platform driving device adopts the magnetic levitation planar motor, a stator of the magnetic levitation planar motor is arranged at the top of the base platform, and rotors of the planar motor are arranged at the bottom of the silicon slice platform. The invention discloses a specific example of one silicon slice platform multi-platform exchange system adopting the moving coil type permanent magnet magnetic levitation planar motor. In the example, the stator of the planar motor adopts a novel planar permanent magnet array, wherein, the magnetizing directions of adjacent permanent magnets mutually form an angle of 45 degrees. The silicon slice platform multi-platform exchange system realizes multi-platform exchange and progressive scanning motion on a plane and improves the productivity, the overlay accuracy and the resolution of the lithography machine by using the planar motor to directly drive the silicon slice platforms.

A high-temperature superconducting magnetic levitation motor is formed by a superconducting motor rotor (1), a motor stator (2), superconducting bearing rotors (3), permanent magnetic bearing stators (4), a rotary dewar (5), an electromagnetic screen (6), torque tubes (7), mechanical protection bearings (8), a main shaft (9), a low-temperature liquid (gas) inlet pipeline (10) and a low-temperature liquid (gas) outlet pipeline (11). The superconducting motor rotor (1) and the superconducting bearing rotors (3) are arranged in the rotary dewar (5) and are cooled by liquid nitrogen or liquid neon or liquid helium or cold helium, the motor stator (2) and the permanent magnetic bearing stators (4) are arranged outside the rotary dewar (5) and are coaxial with the rotary dewar (5), and the two mechanical protection bearings (8) are used in a left and right mode in the radial direction for protecting against the influence brought by the failure of superconducting bearings.

The invention provides an unmanned aerial vehicle take-off or landing control system which comprises a magnet assembly arranged on the side of an unmanned aerial vehicle and a magnetic field assembly arranged on the side of a parking apron. An electrification coil is arranged in the magnetic field assembly. Current is introduced into the electrification coil. A supporting magnetic field is generated by the magnetic field assembly on the side of the parking apron, so that thrust acting on the unmanned aerial vehicle is formed. Resultant force is formed by the thrust and lift force or resistance in the unmanned aerial vehicle take-off or landing process to supplement the lift force or the resistance. The invention further provides an unmanned aerial vehicle take-off or landing control method. In the unmanned aerial vehicle take-off and landing processes, the current of the electrification coil is changed to form the even magnetic field, the thrust acting on the unmanned aerial vehicle is generated to supplement the lift force or the resistance in the take-off and landing processes, the safety performance of the unmanned aerial vehicle is improved, the use energy consumption of the unmanned aerial vehicle is reduced, and the service life of the unmanned aerial vehicle is prolonged.

The invention is an integrating double-framework magnetically suspended control moment gyroscope (MSCMG) magnetic bearing control system, comprising a control circuit, a collecting circuit and a communication interface; wherein, the control circuit comprises a FPGA module, a DSP module and the like; the collecting circuit consists of current, a displacement sensor interface circuit, a double-framework revolution/position interface circuit, an A/D module, and a D/A module; the communication interface comprises a USB interface, RS232 and an SPI interface; the control circuit in the system is used for receiving gyroscope rotor signal processed by the collecting circuit, controlling the stable suspension thereof, transmitting the controlled variable to an upper computer through the communication interface, and realizing on-line monitoring on the suspended gyroscope rotor, data collecting and on-line modification for the controlled variable under the control of the upper computer. The system provided in the invention has the advantages of effectively communicating an inner framework and an outer framework rotational signals under the control of high precision, realizing the integrating design of the control system and the measurement and control system, and satisfying the requirements of speed and precision for the data collecting and the on-line monitoring.

A system for pumping or mixing a fluid using a levitating, rotating magnetic element and various other components for use in a pumping or mixing system are disclosed. The magnetic element is placed in a vessel or container that can be positioned in close proximity to a superconducting element. The vessel or container may be sealed with the magnetic element and a product therein, with the fluid being introduced after sealing. Preferably, the vessel or container is capable of holding fluid volumes greater than 10 liters.

The invention discloses a rotor gravity unloading type magnetic bearing composite motor comprising an external stator, an armature winding, a permanent magnet, a rotor, a magnetic isolation aluminum ring, an internal stator and a suspension control winding. The armature winding is wound in external stator slots. The magnetic isolation aluminum ring is embedded in the rotor. A Halbach type permanent magnet array is surface-mounted on the surface of the rotor. The internal stator has seven internal stator poles including two opposite bias flux magnetic poles, four radial suspension control poles and one gravity direction rotor weight unloading pole. Radial magnetized permanent magnets are surface-mounted on the surface of the bias flux magnetic poles. The suspension control winding is wound on the four suspension control poles. Coupling between the suspension winding and the armature winding in the conventional magnetic suspension motor can be eliminated, and the influence of the rotor weight on suspension control in the conventional suspension motor can also be greatly solved so that the rotor is enabled to stably work at the central balance position without increasing suspension control current, and low power consumption and stable suspension of the magnetic bearing composite motor can be realized.

The disclosed control system includes flywheel body, power amplifier for magnetic bearing, controller for magnetic bearing and adaptive compensator. Through collecting signals including angular rate of frame, speed of rotor, and displacement of rotor, the adaptive compensator carries out adaptive compensation calculation. Sum of calculated compensation quantity and the output of controller for magnetic bearing is connected to the power amplifier for magnetic bearing in order to eliminate disturbing moment on rotor of magnetic suspension caused by moving frame. The invention lowers displacement of rotor caused by rotation of frame, raises response speed and precision of angular rate of frame, and improves response speed and precision of moment output of magnetic suspension control moment.

The invention discloses a single freedom degree magnetic levitation rotor support system, a magnetic levitation bearing and a magnetic biasing weight reducing device. The single freedom degree magnetic levitation rotor support system is composed of an attraction type axial magnetic levitation bearing (24), attraction type radial magnetic levitation bearings (25,26), magnetic biasing weight reducing devices (27,28) and air gap limit protective devices (29,30) of the axial and radial magnetic levitation bearings which are all arranged in the same movement mechanism. Active cell parts and stator parts of the axial and radial bearings are composed of a permanent magnetic field or a controllable magnetic device not generating non-work air gap magnetic leakage loss. So long as designing margin of the magnetic field is enough, the system of the invention can operate stably without adopting any form of sensor feedback control technology.

The invention provides an all-PM suspension wind power generator, comprising frame, mechanical bearing, shaft and wind turbine, where the wind turbine is arranged at the front part of the shaft, the shaft is connected via the mechanical baring with the frame and it is characterized in that: one or more groups of PM suspension devices are arranged between the wind turbine and the mechanical bearing and use the potential difference between the corresponding magnetic poles encircling the shaft and respectively arranged on the shaft and frame to generate upward magnetic force so as to eliminate the effect of the wind turbine gravity.