Abstract:
A system to control the fixed pass/spring mechanical resonance of the motor in conjunction with a model of the motor (10) that estimates the present position and allows the determination of the motor stator voltage pattern which will produce the requested output force. This approach effectively eliminates the electrical restoring force from the motor dynamics and minimizes the problems associated with the varying resonant frequency of the motor (10).
Abstract:
A device includes a stage (4), a force applying unit (7, 10) arranged to apply a magnetically repulsive force to the stage (4), the force applying unit (7, 10) including a first magnet (9) provided at the stage (4), and a second magnet provided at an end of a movement stroke of the stage (4) so as to face the first magnet (9), a driving unit (5, 6) arranged to drive the stage (4) within the movement stroke, a magnetic-flux reinforcement unit (11, 13) arranged to reinforce magnetic flux of the second magnet, and a magnetic shield (16) arranged to shield the magnetic flux of the second magnet.
Abstract:
The invention relates to a synchronous electromechanical transformer that can be used as a multi-phase motor and generator, has a high specific torque, a small or negligible stop moment, a small moment irregularity, can be quietly operated, and has good heat permeability between the windings and the housing. It contains a rotor having uniformly distributed magnetic poles (4), and two stators (2) with concentrated windings (8) of at least two electrical phases. The individual stator contains the same number of similarly arranged electromagnetic poles (9) of each of at least two electrical phases arranged in related groups (7) of at least two electromagnetic poles of the same electric phase. The stator poles (9) can contain magnetically permeable polar cores and can be uniformly or non-uniformly distributed. The number of electromagnetic poles of the stator differs from that of the rotor by the product between the number of stator groups (7), the electromagnetic poles of said stator groups pertaining to the same electrical phases, and a natural number that is not a multiple of the number of electrical phases. A radial, axial and linear embodiment of the transformer is possible.
Abstract:
A torus motor system includes a hollow stator and a rotor which is driven along a rotor path formed within the hollow stator by a magnet system. The rotor operates as a piston within the rotor path to intake and discharge fluid therefrom. The forces on the rotor all tend to center the rotor within the rotor path. The rotor is accelerated away from the inlet port on the magnet system and decelerated as the rotor approaches the discharge port.
Abstract:
A linear compressor assembly includes a housing having a bore formed therein, the bore being axially oriented along a first axis, a piston reciprocally disposed within the bore, and a plurality of drive coils adjacent the bore for energizing the drive coils to produce a magnetic field capable of displacing the piston within the bore substantially along the first axis. A controller is used for selectively controlling energizing of the drive coils. A cooling system is at least partially disposed in the housing and the cooling system is used for cooling the apparatus.
Abstract:
A traverse device (3) has an arm driving part (7) which rotatively reciprocates an arm (6) having a yarn guide (6a) to traverse a yarn (1) on a takeup bobbin (2) that winds the yarn (1). The arm driving part (7) comprises an electrical coil (12) provided in the arm (6), two yokes (14a, 14b) formed into arc shapes around the center of axis of an arm shaft (9) as the center of rotative movement of the arm (6), and an air gap (15) that is sandwiched between the two yokes (14a, 14b) and has magnetic fields formed inside, and a part of the electrical coil (12) is inserted in the air gap (15). The respective two yokes (14a, 14b) are provided with permanent magnets (16a, 16b), a central yoke (14m) that divides the air gap (15) into two rows is provided, and in the respective two-row air gaps (15a, 15b), magnetic lines (17a, 17b) turned in the radial direction and being opposite each other are formed by the permanent magnets (16a, 16b). A part of the electrical coil (12) is inserted in the respective two-row air gaps (15a, 15b) so as to surround the central yoke (14m).
Abstract:
A system to control the fixed pass/spring mechanical resonance of the motor in conjunction with a model of the motor (10) that estimates the present position and allows the determination of the motor stator voltage pattern which will produce the requested output force. This approach effectively eliminates the electrical restoring force from the motor dynamics and minimizes the problems associated with the varying resonant frequency of the motor (10).
Abstract:
Servo control using ferromagnetic core material and electrical windings is based on monitoring of winding currents and voltages and inference of: magnetic flux, a force indication; and a magnetic gap, a position indication. The third order nonlinear servo control is split into nested control loops: a fast non-linear first order inner loop (1636) causing flux to track a target by varying a voltage output; and a slower almost linear second-order outer loop (1650, 1670, 1680) causing magnetic gap to track a target by controlling the flux target of the inner loop.
Abstract:
A traverse device (3) has an arm driving part (7) which rotatively reciprocates an arm (6) having a yarn guide (6a) to traverse a yarn (1) on a takeup bobbin (2) that winds the yarn (1). The arm driving part (7) comprises an electrical coil (12) provided in the arm (6), two yokes (14a, 14b) formed into arc shapes around the center of axis of an arm shaft (9) as the center of rotative movement of the arm (6), and an air gap (15) that is sandwiched between the two yokes (14a, 14b) and has magnetic fields formed inside, and a part of the electrical coil (12) is inserted in the air gap (15). The respective two yokes (14a, 14b) are provided with permanent magnets (16a, 16b), a central yoke (14m) that divides the air gap (15) into two rows is provided, and in the respective two-row air gaps (15a, 15b), magnetic lines (17a, 17b) turned in the radial direction and being opposite each other are formed by the permanent magnets (16a, 16b). A part of the electrical coil (12) is inserted in the respective two-row air gaps (15a, 15b) so as to surround the central yoke (14m).
Abstract:
A coil 20 for use in an actuator in a lithographic projection apparatus. The coil 20 is formed of a strip 21 of electrically conducting sheet-material that is wound round a winding axis 22. Respective turns of the strip 21 of sheet-material are separated by an electrically non-conducting layer 25.