Abstract: A control circuit for a reluctance machine having two mutually movable parts and at least one inductive phase winding adapted for a certain maximum drive current value. The method includes detecting when a phase winding is in a non-drive mode; causing a test current, having a second maximum value lower than said certain maximum value, to flow through the phase winding and through a current sensor when the winding is in the non-drive mode; and establishing a mutual position in dependence of the output of said current sensor.

Abstract: A waterproof speaker has a yoke provided with a magnet and a center pole therein. A top plate is attached on the periphery of the yoke, wherein the center pole protrudes through a center opening of the top plate. A frame is mounted on a front surface of the top plate. A cone-shaped diaphragm has a middle through-hole that mounts a bobbin and is enclosed by a cap, wherein the diaphragm has its rim portion attached to a forward end portion of the frame via an edge portion. A voice coil is mounted around the periphery of the bobbin. A waterproof damper is supported by the frame and defined with a hole through which the bobbin is protruded, and the damper is formed of two layers, wherein a first layer is cloth material, and a second layer is waterproof material to prevent moisture entering the yoke.

Abstract: A passive radiator and method is disclosed which improves frequency response linearity and greatly reduces the possibility that wobble of a passive radiator which will occur without the displacement limitations of a spider containing speaker structure. Two substantially flat surfaced speaker diaphragms are tied together and supported by two sets of surrounds oriented in opposite directions to reduce the non-linearity in the surround spring rate and improve low frequency sound generation. A vent (pressure relief) system is provided to improve the frequency response and range of motion of the passive speaker system. A progressive surround roll arrangement provides for improved sound quality by utilizing localized position based extension while maintaining the range of maximum travel during resonance.

Abstract: Axial error calculation unit is provided for estimating an axial error &Dgr;&thgr; between a d-q axis and a dc-qc axis by using Ld, Lq, Ke, Id*, Iq*, Idc and Iqc in a range of all rotational speeds except zero of a rotational speed command of a synchronous motor, Ld denoting an inductance on a magnetic pole axis d of the synchronous motor, Lq an inductance on a q axis orthogonal to the magnetic pole axis d, Ke a generated power constant of the motor, Id* a current command of the d axis, Iq* a current command on a q axis, Idc a detected current value on an assumed dc axis on control, and Iqc a detected current value on an assumed qc axis orthogonal to the assumed dc axis. Irrespective of presence of saliency, position sensorless control can be achieved in a wide range a low to high speed zone.

Abstract: The present invention provides a radio frequency (“RF”) shielded and acoustically isolated enclosure that efficiently employs multiple layers of sound insulation and absorbs airborne noise and the noise provided by magnetic resonance imaging (“MRI”) equipment through the supports of such equipment. The RF enclosure uses multiple layers and types of insulating materials positioned to maximize the noise absorption of the RF enclosure. This reduces the cost and space required by the enclosure. In one embodiment the enclosure includes a ceiling, a floor and a plurality of walls. The ceiling and walls include one or more multiple layers of different indulating materials that either abut each other or form air gaps. In one embodiment the floor includes a heavy metal plate on which the MRI equipment sits. The plate elastically couples to a conductive shield. The elastic coupling attenuates certain frequencies above the natural frequency of the metal sheet.

Abstract: The present invention aims to first start the rotation of a rotor according to a first sequence for causing currents to flow in armature windings of three phases U, V and W upon startup of a three-phase brushless motor to thereby reduce an inrush current at the startup thereof, thus making it possible to lighten an electrical load on each electronic part used for control. Also the present invention aims to perform switching to an original second sequence for causing currents to flow in the armature windings of the two phases U and V, V and W or W and U of the three-phase brushless motor after the startup of the three-phase brushless motor to thereby provide a period for an open state of each terminal and make dead band control or the like unnecessary, thus making control of the three-phase brushless motor easier.

Abstract: A control device for a plurality of rotating electrical machines has a single current control device with an inverter, gate driver, and a motor controller, which supplies a control current to each rotating electrical machine allowing rotation control in response to the rotational phase of the rotor. In this control device, the current control device determines the control current of each rotating electrical machine based on the target torques and rotational angular velocities of all rotating electrical machines, and supplies a composite current obtained by combining the determined control currents for each rotating electrical machine to all rotating electrical machine. In this control device for a plurality of rotating electrical machines, the required voltage does not exceed the voltage of the power source and the peak value of the composite current does not exceed the permitted range of the inverter.

Abstract: An improved sound attenuating device for use in a gas transportation duct, said device comprising a core of acoustically absorptive material substantially enclosed within an impervious film to prevent direct contact between the acoustically absorptive material and gas flowing through said gas transportation duct, wherein said enclosed absorptive material is maintained in position between at least two perforated facing plates and further wherein there is provided between the perforated facing and the impervious film and between the impervious film and the acoustically absorptive material spacing means to allow unrestricted movement of the impervious film in the void between the perforated facing and the acoustically absorptive material, while preventing contact between the film and the perforated facing and between the film and the acoustically absorptive material, and blocking means to impede the internal flow of gas between the film and the perforated facing and between the film and the acoustically absorpti

Abstract: A support pad for use in a hearing device of the type comprising a casing having an inner surface defining a cavity; and a sound receiving, amplification and transmitting system within the cavity in the casing, which system includes a transducer. The support pad includes a layer of conformable metal having first and second opposite major surfaces, and a layer of viscoelastic material along its first major surface. The support pad has an attachment portion with the layer of viscoelastic material along the attachment portion being adapted to be adhered to a side surface of the transducer, and has at least one tab portion adapted to project away from the transducer adjacent an end of the transducer.

Abstract: A wiper control device in which an abnormal condition of a FET is detected by distinguishing an action of an overheat-cutting protective function normally difficult to be detected with measuring the drain voltage of the FET and by which the control of the pertinent FET is restrained upon the detection of abnormality so as to prevent a short circuit in the wiper control device from occurring. When an FETB (Qb) is set on, whether or not a drain voltage Vd is lower than Vpe ({fraction (l/2)}VG) is judged (step S5), and if lower, it is judged that the drain and ground is short-circuited, that is, an overheat-cutting protective function is acted, and “1” is added to the number of times of short circuit detection Perror (step S7). It is judged whether or not the added value of the number of times of short circuit detection Perror reaches a reference value (step S11).

Abstract: An improved garage door opener is disclosed. The garage door opener has a motor drive unit for opening and closing a garage door. The motor drive unit has a microcontroller. Connected to the motor drive unit is a wall console that resides inside the garage. The wall console also has a microcontroller. The microcontroller of the motor drive unit is connected to the microcontroller of the wall console by means of a digital data bus.

Abstract: A method and a device for incrementally determining the actual reversal of a rotary drive that rotates on slightly even after a preceding signal switching the rotational direction is applied. A sequence of pulse signals (N; S; SL) that are proportional to the rotational speed, with an intermittent reference signal (SL) that is different from said pulse signals, is output by an asymmetric transmitter wheel (1) and received by a single sensor (3) located on the stator. A pulse signal correction value for determining the pulse signal count value corresponding to the actual reversal (U) of the rotary drive is defined, based on the number of pulse signals that are measured between two reference signals following a switch of direction.

Abstract: A calculation system for calculating the control signals which are designed to perform a frequency-dependent weighting of the angular velocity signals and the angular position signals. The angular velocity indicators are preferably used for stabilization in a high frequency band while the angular position indicators are suitable for stabilization in a low frequency band. A further calculation system which is designed to perform the frequency-dependent weighting such that the control signals for frequencies below a certain frequency are substantially determined by the angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

Abstract: A soundproof cover includes a sealing layer, a sound insulation layer, and a vibration inhibition layer. The sound insulation layer has a peripheral portion, is to be disposed so as to contact at least the peripheral portion with a noise source, and exhibits elasticity. The sound insulation layer is formed as a hard plate shape, has an installation portion to be fastened to the noise source, and is disposed so as to cover the sealing layer. The vibration inhibition layer is disposed on at least a part of an interface between the sealing layer and the sound insulation layer so as to adhere to the sound insulation layer, and inhibits the sound insulation layer from vibrating.

Abstract: A method of generating low voltage auxiliary power forms for electric or hybrid vehicle use by tapping power from the traction motor primary winding with a secondary winding and rectifier.

Abstract: The invention relates to a motor control circuit for a computer system fan motor, comprising a temperature sensor, a sensor amplifier, a fan command for applying a voltage to the fan motor according to the output of the sensor amplifier, and feedback control means. The circuit of claim also comprises means for stopping the supply of voltage across the fan motor terminals, irrespective of the output of the temperature measuring means. The sensor amplifier allows easy setting of the parameters of the voltage according to the temperature measured by the temperature sensor.

Abstract: A power driver for driving a signal on a load using voltage-mode driver. A system processor generates commands indicating a programmed drive signal desired from the voltage-mode driver. A lead compensator determines a compensated command to compensate for an admittance function of the load. The compensated commands are coupled to the voltage-mode driver, such that the voltage-mode driver generates a voltage output based upon the compensated command.

Abstract: A rotation detector apparatus and a rotation control apparatus for the DC motor is disclosed wherein rotational operations of a rotor of the DC motor are controlled by detecting at least one of the rotational direction, the rotational speed, the cumulative rotation number, and the rotational position of the rotor. The pulsed output signal from at least one motor rotor rotation detector brush is processed by signal processing circuitry to regulate the at least one of the rotational direction, the rotational speed, the cumulative rotation number, and the rotational position of the rotor.

Abstract: An inverter-fed three-phase electrical motor (1) for a household appliance is grounded through a protective conductor (8), with the motor being particularly provided for the direct drive of washing machines. The motor includes a pick-up for high-frequency currents originating from an actuation of the inverter (7) and conducts the currents to one pole of a D.C. voltage supply (13) for the inverter (7) through an ohmic or capacitive shunt path (18-19), with the shunt path leading from a stator (3) of the motor which is installed electrically insulated into the household appliance and is not connected to the protective conductor (8).

Abstract: A substrate transfer system comprises plural end-effectors that are placed so as to touch a periphery of a cone having a vertical angle at a 2&thgr; angle with respect to a central axis at an arbitrary &thgr; angle to a horizontal plane, wherein substrates are interchanged and simultaneously transferred where the end-effectors are in a horizontal position. Besides, since the end-effectors are vertically located, the minimum rotational radius of the system that is projected to a horizontal plane, can be reduced. This contributes toward the reduction of an installation area for a substrate processing equipment in which the substrate transfer system is equipped.