Patents Examined by Patrick R. Salce
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Patent number: 4910423Abstract: An electric motor and brake comprises a stator, a rotor, a rotatable brake member and a fixed brake member, the rotor carrying a magnetic actuator at one of its ends. A coupling mechanism couples the rotatable brake member to the motor to rotate with the rotor but to be axially displaceable with respect thereto, and the rotatable brake member is made at least in part of magnetic material, so that it is attracted axially toward the magnetic actuator and away from the fixed brake member by the magnetic field produced by current flowing through the rotor. A spring is provided for urging the rotatable brake member away from the actuator and into engagement with the fixed brake member. The magnetic actuator is U-shaped and opened at one side, and the stator is in line at both its ends with the rotor.Type: GrantFiled: January 5, 1988Date of Patent: March 20, 1990Inventor: Manuel M. Werber
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Patent number: 4910419Abstract: In a linear actuator comprising a motor-driven screw shaft, an overload detection mechanism comprises a pair of cup-shaped spring seats with substantially cylindrical portions. The spring seats are mounted at one end of the screw shaft by a pair of bearings and have a spring therebetween under a predetermined preload. Limit switches are provided for detecting overload on the screw shaft as a result of axial movement of the spring seats. The cylindrical portions of the cup-shaped spring seats serve as strikers for said limit switch means.Type: GrantFiled: February 28, 1989Date of Patent: March 20, 1990Assignee: Tsubakimoto Chain Co.Inventors: Shuji Hayashi, Kenichiro Nakamura
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Patent number: 4910475Abstract: Hybrid stepping motor apparatus that produces a step angle of 1/K.sub.p times the pitch angle .DELTA..theta..sub.p of the stator on rotor teeth, where K.sub.p is the number of phases for the motor, using a plurality of stator poles whose center-to-center angular spacings are not uniform, and depend on the number of stator poles used. In one embodiment with M poles, the first M-1 center-to-center pole angular spacings are equal to a first angle A, and the Mth center-to-center pole angular spacing is an angle B with .vertline.A-B.vertline.=m.DELTA..theta..sub.p, where m is a positive integer.Type: GrantFiled: March 28, 1989Date of Patent: March 20, 1990Assignee: Linex Technology CorporationInventor: Ted T. Lin
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Patent number: 4910420Abstract: A novel brushless electric motor is characterized by a printed circuit board having at least one integral portion extending from the printed circuit board plane for establishing the interrelationship between the printed circuit board and another motor component. The present motor has a more precisely located triggering sensor for the commutation circuit and is readily adapted to automated assembly by the use of the present printed circuit board.Type: GrantFiled: July 27, 1988Date of Patent: March 20, 1990Assignee: Nidec CorporationInventors: John W. Hoover, Allen C. Potter, Anthony C. Laraia
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Patent number: 4910451Abstract: A voltage regulator circuit for an AC generator of an automobile is disclosed. The circuit comprises, in addition to the conventional elements, a transistor turned on and off in phase with the power transistor by the control transistor of the voltage detecting circuit. The collector of this additional transistor is coupled to the positive terminal of the battery through a resistor, while the emitter thereof is grounded. A serial circuit of a resistor and a capacitor forming a positive feedback circuit is coupled across the collector of this additional transistor and the base of the control transistor, a biasing resistor being coupled across the base and emitter of the control transistor. Thus, when the control transistor is turned on, the charging current of the capacitor produces a forward bias across the base and emitter of the control transistor; when the control transistor is turned off, the discharging current of the capacitor produces a reverse bias thereacross.Type: GrantFiled: February 7, 1989Date of Patent: March 20, 1990Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Shiro Iwatani, Kenji Itoh
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Patent number: 4908536Abstract: The electrical termination impedance of a variable reluctance electro-mechanical transducer is changed automatically in response to the frequency of vibration applied to the transducer, to provide the optimum electrical termination impedance which produces the highest effective mechanical impedance at said frequency. The transducer includes magnetic cores interconnected by a spring formed by cutting a relatively thin medial annulus in a relatively thick flat disk. A digital logic circuit uses a signal counter and NAND gates to determine the frequency and close the appropriate fast-acting relay in a parallel array of capacitor-relays. A negative-impedance electrical termination provides a high mechanical impedance over a broad band of frequencies. A shunting circuit eliminates spurious resonances by providing substantially no shunting in the transducer-terminating circuit at resonant frequency, and substantial shunting in the terminating circuit at other frequencies.Type: GrantFiled: January 25, 1988Date of Patent: March 13, 1990Inventor: Albert A. Hudimac
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Patent number: 4908757Abstract: The invention relates to a static frequency converter in a housing, especially a frequency converter controlling and/or adjusting the performance data of an electromotor. The housing is shaped as a pressure-resistant casing sealed toward the ambient and at least partially provided with a filler serving as a heat conductor for the dissipation of heat to the surface of the casing.Type: GrantFiled: January 27, 1989Date of Patent: March 13, 1990Assignee: Grundfos International A/SInventors: Niels D. Jensen, Jorgen Christensen
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Patent number: 4908541Abstract: A stator coil of a generator for vehicles is provided with a stator coil construction and method for winding the stator coil around the core. The coil is wound around the stator core so that a portion of the stator coil projects from one or both sides of the stator core in the axial (longitudinal) direction of the core. The projecting portion of the stator coil closely surrounds the rotor core and is composed of inner and outer wire batches between which are formed slits which permit cooling air to pass therethrough and cool the coil more efficiently. The cooling air is generated by a fan which is attached to the rotor core facing the inner surface of the projecting portion of the stator coil.Type: GrantFiled: August 24, 1987Date of Patent: March 13, 1990Assignee: Mitsuba Electric Mfg., Co., Ltd.Inventors: Takashi Kawazoe, Shigeru Akutsu, Nobuhisa Hongo
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Patent number: 4908347Abstract: An AC electrical machine which includes a superconducting, diamagentic flux shield cylinder enclosing the stator windings such that the magnetic flux produced by the machine's rotor is bottled within the flux shield.Type: GrantFiled: July 7, 1988Date of Patent: March 13, 1990Assignee: Allied-Signal Inc.Inventor: Joseph Denk
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Patent number: 4908540Abstract: An electric generator organization, particularly adapted for small vehicles such as motorcycles, is described in which a rectifier mechanism electrically disposed between the stator and the rotor is mechanically connected to the rotor for rotation therewith during engine startup and disconnected therefrom during periods of normal engine operation. An operating circuit enables efficient transmission of electric current from the battery to starting coils in the generator only during the period of engine startup. During periods of normal engine operation, the transmission of electric current is from generating coils in the generator to the battery. Included in the operating circuit is an engine operation detector that prevents excessive current feed from the generator coils to the rectifier mechanism.Type: GrantFiled: October 12, 1988Date of Patent: March 13, 1990Assignee: Honda Giken Kogyo Kabushiki KaishaInventors: Shoji Motodate, Nobuaki Komuro, Yukio Miyamaru
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Patent number: 4908535Abstract: The commutating poles of vehicular-type dc motors, for example for trolley buses or trolley cars, are made by winding, on edge, a copper strip, permitting the wound copper strip to resiliently, spring-like expand so that the individual spiral loops thereof will be slightly spaced from each other, and then exposing the copper strip in a fluidized bed to an insulating powder, for example polyethylene or polyurethane, which is subsequently cured in a hardening or sintering process.Type: GrantFiled: October 26, 1988Date of Patent: March 13, 1990Assignee: Robert Bosch GmbHInventors: Helmut Kreuzer, Klaus-Peter Meier
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Patent number: 4908754Abstract: In an inverter-type power supply, a self-oscillating full-bridge inverter is powered by unfiltered full-wave-rectified 120 Volt/60 Hz power line voltage and controllably triggered into oscillation each half-cycle of the power line voltage by way of simultaneously triggering two of the bridge's four transistors into conduction simultaneously. This is accomplished by way of discharging a charged-up capacitor by way of a Diac through a special trigger winding on each of two saturable current feedback transformers; each of which controls a pair of the bridge transistors.Type: GrantFiled: April 21, 1987Date of Patent: March 13, 1990Inventor: Ole K. Nilssen
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Patent number: 4908534Abstract: A stator for an electric motor for driving a spindle of a spinning machine, including a magnetic core having a stack of magnetically active plates and a plurality of coils received within the plates, projecting beyond the top and bottom surfaces of the magnetic core. A protective covering encloses the projecting portions of the coils to protect the coils from impact forces or other disturbances.Type: GrantFiled: October 13, 1988Date of Patent: March 13, 1990Assignee: Zinser Textilmaschinen GmbHInventors: Hans R. Gubler, Gustav Fetzer
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Patent number: 4907145Abstract: In the sine wave inverter disclosed herein the input of a low pass filter is switched at high frequency between positive and negative supply voltages. The switching is controlled by a comparator which is responsive to a composite of signals which include contributions from a sine wave control signal at the same frequency desired for the output and a square wave control signal which is at a frequency substantially higher than the desired output frequency. The filter input voltage is attenuated and phase adjusted to generate a feedback signal having a high frequency component which is substantially in phase with the high frequency control signal. This feedback signal is combined with the sine wave and high frequency square wave control signals to generate the composite of signals which controls the comparator. Accordingly, the duty cycle of the filter input voltage is varied in correspondence with both the sine wave control signal and the loading of the inverter output.Type: GrantFiled: May 11, 1989Date of Patent: March 6, 1990Assignee: Belmont Instrument CorporationInventor: David E. Cassidy
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Patent number: 4906860Abstract: A control device for an active filter according to the present invention comprises a ROM circuit for producing output signals sin .theta. and cos .theta. from a phase signal generated from a PLL circuit, a first multiplier for multiplying a load current detection signal by the output signals sin .theta. and cos .theta., a sample-holding circuit for integrating the output signal of the first multiplier and holding the integrated value to produce peak values of valid current component and invalid current component for constituting the basic wave component of the load current, a second multiplier for multiplying the peak values by the output signals sin .theta. and cos .theta., and a PWM control circuit for PWM-controlling the input current of the active filter with a harmonic current signal obtained as the difference between a basic wave current signal of the load current during a period of next one period of the single-phase a.c.Type: GrantFiled: May 5, 1989Date of Patent: March 6, 1990Assignee: Mitsubishi Denki Kabushiki KaishaInventor: Takeaki Asaeda
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Patent number: 4906884Abstract: A flat motor is disclosed comprising a motor housing having a first engaging mechanism, a magnet fixed to the motor housing, a holder plate attached to the motor housing and provided with a pair of brush holders. The holder plate has a second engaging mechanism engaging the first engaging mechanism. A third engaging mechanism engages an inside surface of the magnet. The holder plate can be positioned coaxially with the motor housing by the engagement of the first engaging mechanism with the second engaging mechanism, the magnet can be positioned coaxially with the holder plate by the engagement of the third engaging mechanism with the magnet. The motor housing, the holder plate and the magnet can all be positioned coaxially with one another without use of a particular jig, thereby improving the assembly of the flat motor and increasing the productivity of the motor.Type: GrantFiled: October 3, 1988Date of Patent: March 6, 1990Assignee: Sanden CorporationInventor: Toshiyuki Teshigawara
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Patent number: 4907144Abstract: A method for controlling a frequency converter having multi-phase output is disclosed and a frequency converter for applying the method. In order to achieve a good waveform the currents of the frequency converter are controlled via modulation in such manner that the current modulation periods of each phase are interlaced with the modulation periods of the other phases.Type: GrantFiled: June 17, 1988Date of Patent: March 6, 1990Assignee: Kone OyInventor: Heikki Tuusa
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Patent number: 4906861Abstract: A superconducting switching device having no moving components for reversing current flow through a load. This load typically is a superconducting magnet and, in this application, the present invention also selectively serves as a persistent switch. The invention includes a pair of switching units connected between the load (magnet) and a current source. These switching units each have a pair of superconductor members and a mechanism for selectively producing in the switching units either a substantial electrical resistance or no resistance. Through the use of a control logic, the level of resistance of the switching units can be changed to effect the direction of current flow. In the case of the superconductor magnet, both switch units can be simultaneously made to have substantially zero resistance, and their interconnection forms the persistent switch for the superconducting magnet.Type: GrantFiled: September 30, 1988Date of Patent: March 6, 1990Assignee: Cryomagnetics, Inc.Inventors: Apurba Roy, David M. Coffey
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Patent number: 4906881Abstract: A rotor, rotatably coupled to an output shaft, is slidable axially along the shaft, the rotor and its coupling being biased axially out of engagement with a stator into engagement with a hand wheel to effect rotational coupling of the hand wheel to the output shaft. Electrical energization of the motor attracts the rotor to the stator, axially sliding the rotor and its coupling against the bias to automatically uncouple the rotary connection with the hand wheel, and to effect a motor driven coupling with the output shaft.Type: GrantFiled: February 28, 1989Date of Patent: March 6, 1990Assignee: Eaton CorporationInventor: Richard K. Knight
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Patent number: RE33184Abstract: What is proposed is an electronic circuit for controlling the amount of AC power delivered to an inductive or resistive load which continuously measures the actual phase lag between the load current and applied voltage and automatically adjusts the firing angle to provide the desired amount of AC power. The circuit includes an auxiliary on/off input with soft start and independently adjustable time delays for the on and off functions and also incorporates an input for remote power level control and features a half-wave rectified mode which delivers pulsating DC power to the load.Type: GrantFiled: January 28, 1988Date of Patent: March 20, 1990Assignee: Industrial Power Controls, Inc.Inventors: Raymond T. Westfall, John F. Kohls