Current Responsive Patents (Class 361/57)
  • Publication number: 20030072114
    Abstract: Compatibility with a current transformer having several kinds of rated current ratios is achieved by finding out a formula of relationship between errors arising in a transformer input circuit and detectable ranges set as setting values of the input circuits which can be optimally set. In connection with that, by dispensing with a gain control section, the number of components, the mounting area and the cost can be reduced. Arithmetic expressions representing the relationship among errors arising in the transformer input circuit, the instrumentation ranges of the input circuits, and detectable errors have been derived. Further by optimally setting the detectable ranges of the input circuits, which are the parameters of the arithmetic expressions, the configuration compatible with a current transformer having several kinds of rated current ratios is achieved.
    Type: Application
    Filed: September 20, 2002
    Publication date: April 17, 2003
    Applicant: Hitachi,Ltd.
    Inventors: Daisuke Maeda, Takashi Funawatari, Yoshiyasu Watanabe
  • Patent number: 6532405
    Abstract: An exemplary embodiment of the invention is a method for detecting a potentially locked axle on a vehicle propelled by an AC motor. The method includes conducting a speed test by estimating axle speed and comparing estimated axle speed to measured vehicle speed. The existence of a potential locked axle condition is determined based on the comparing of estimated axle speed to measured vehicle speed. Additional tests are disclosed for determining a potential locked axle condition and a sensor fault condition.
    Type: Grant
    Filed: August 9, 2000
    Date of Patent: March 11, 2003
    Assignee: General Electric Company
    Inventors: Ajith Kuttannair Kumar, Jeffrey Louis Daigle
  • Publication number: 20020181180
    Abstract: Over-current protection is accomplished in an output transistor (MP) of an electronic circuit wherein an input signal (Vgatedrive) Is Applying to a first conductor (19) coupled to a gate of the output transistor to cause an output current (Iout) to flow through the output transistor and an output terminal (11) of the electronic circuit. A limit voltage (VLIMIT) who is applied to an input (21) of a voltage clamping circuit (18) to cause a clamping current to flow in the first conductor (19) as needed to prevent the magnitude of the input signal (Vgatedrive) from being less than the magnitude of the limit voltage (VLIMIT) so that the output current (Iout) is limited to a maximum current limit determined by the limit voltage (VLIMIT).
    Type: Application
    Filed: April 19, 2001
    Publication date: December 5, 2002
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Vadim V. Ivanov, David R. Baum
  • Publication number: 20020176217
    Abstract: The present invention relates to an overload protector structure of an extension cord receptacle that mainly comprised a fire wire conducting plate of a switching unit (or a receptacle unit) connected with an overload protector in the extension cord receptacle to extend properly; the overload protector has a housing member, a power input plate exposed at the said housing member, a temperature sensing plate is fixedly connected to an inner end of the power input plate, the said overload protector further penetrates outward through a slot channel from a contact point, the fire wire conducting plate can fitly extend into the said slot channel and contacts with the contact point of the temperature sensing plate; thereby, the effectiveness of rapid connection and eliminating the soldering joint point is possessed between the overload protector and the switch unit (or the receptacle unit).
    Type: Application
    Filed: May 23, 2001
    Publication date: November 28, 2002
    Inventor: Chyong-yen Huang
  • Patent number: 6452235
    Abstract: A floating body ESD protection circuit positioned between and coupled to an I/O pad and an internal circuit. A p-type depletion mode transistor is used to control the body of an n-type enhancement mode transistor. When the p-type depletion mode transistor is triggered, the body of n-type enhancement mode transistor remains grounded. If the p-type depletion mode transistor has not been triggered, the body remains in a floating state, lowering the range of the snapback voltage. As a consequence the ESD protection circuit is able to function more rapidly. Similarly, an n-type depletion mode transistor is used to control the body of a p-type enhancement mode transistor. When the n-type depletion mode transistor is triggered, the body remains coupled to a high voltage. If the n-type depletion mode transistor has not been triggered, the body is in a floating state. Thus, the range of the snapback voltage can be lowered, enabling the ESD protection circuit to function more rapidly.
    Type: Grant
    Filed: September 19, 2000
    Date of Patent: September 17, 2002
    Assignee: United Microelectronics Corp.
    Inventor: Liang-Choo Hsia
  • Patent number: 6452771
    Abstract: A method and system for detecting a potentially destructive state of an arrangement containing electronics and for terminating the potentially destructive state. In the method and system currents consumed by the electronics through connecting mechanisms from at least one supply voltage are measured. The measured currents are compared with respective stored maximum permissible currents stored in a memory. Further, the connecting mechanisms are disconnected from the at least one supply voltage to thereby ground the arrangement when at least one consumed current is measured as higher than the respective maximum permissible current.
    Type: Grant
    Filed: June 13, 2000
    Date of Patent: September 17, 2002
    Assignee: Thales Nederland B.V.
    Inventor: Paulus Van Kempen
  • Patent number: 6445276
    Abstract: A fuse apparatus (1) is provided for selectively interrupting a load current (Ia) flowing between a pair of associated conductor leads. The fuse apparatus includes at least two spaced apart electrically conductive contact elements (5) operatively connected with the associated conductor leads. A fuse element (7) is connected to the contact elements (5) using an electrically conductive connection material (9) to allow the current (Ia) to flow between the pair of associated conductor leads. The connection material (9) is adapted to electrically disconnect the fuse element (7) from the contact elements (5) when the current (Ia) exceeds a predetermined current intensity. The connection material (9) has an intrinsic electrical transition resistance characteristic whereby the material develops a temperature in proportion to an intensity of the current. The connection material melts as the current increases to separate the fuse element from the contact elements.
    Type: Grant
    Filed: March 4, 1999
    Date of Patent: September 3, 2002
    Assignee: TRW Automotive Electronics & Components GmbH & Co. KG
    Inventors: Uwe Schön, Dieter Bornhorst, Joachim Korherr, Joachim Jüngst
  • Publication number: 20020118496
    Abstract: A novel motor driver with an active snubber circuit. The motor driver is interposed between an external electrical power source and an electrical motor. The electrical motor is driven in first and second states such that the electrical motor produces an inductive flyback current when it switches torque direction. The motor driver comprises a reverse voltage protector in series between the power source and the electrical motor allowing flow of electrical power to the motor; and a capacitor arranged in parallel circuit with the motor between the motor and the diode (or other reverse voltage protector). The active snubber circuit is in parallel circuit with the motor between the diode and the electrical motor. The active snubber circuit comprises a switch having a sensor responsive to increases in the bus voltage resulting from the inductive flyback current and a resistor in series with the switch regulating electrical current flow.
    Type: Application
    Filed: February 26, 2001
    Publication date: August 29, 2002
    Applicant: Woodward Governor Company
    Inventor: David C. Petruska
  • Patent number: 6349022
    Abstract: An overcurrent protection system gives rapid response to relatively small overcurrents has a sensor element and an interruption element in series between a power source and a load. The sensor element is functionally linked to the circuit interruption element via a control element. When current exceeds a predetermined amount, the sensor element transfers heat to the control element which causes the circuit interruption element to change from a conducting state to non-conducting fault state. A latching arrangement causes the protection system to remain in the non-conducting fault state until reset. The control element may include a PTC device or a bimetal switch.
    Type: Grant
    Filed: April 7, 2000
    Date of Patent: February 19, 2002
    Assignees: Tyco Electronics Corporation, EWD, L.L.C.
    Inventors: Inho Myong, Michael Brown, Douglas A. Burcicki, Glen A. DeGrendel
  • Publication number: 20010033471
    Abstract: A current detection switch comprising a measured conductor into which a measured current flows, a plurality of magnetoelectric devices placed sandwiching the measured conductor so as to have magneto-sensitive faces on sides to which a magneticflux generated by the measured current is input, each of the magnetoelectric devices for outputting a magnetoelectric signal when the magnetic flux exceeds a predetermined value, and a computation section for outputting a logical multiplication of the magnetoelectric signals from the plurality of magnetoelectric devices as a detection signal.
    Type: Application
    Filed: April 24, 2001
    Publication date: October 25, 2001
    Inventors: Mitsuaki Morimoto, Takashi Gohara, Yoshinori Ikuta, Yasuhiro Tamai
  • Patent number: 6278381
    Abstract: A fault protective device (48) for limiting the maximum current and voltage applicable to electronic components and wiring (26, 30) located in the fuel tank (10) of an aircraft. Particularly, a fuel gauging system circuit (18) extends from a generator (20) located outside the tank to at least one probe (14) located in the tank and from the probe to instrumentation (24) outside the tank. The device is electrically coupled to the circuit at the tank wall (28) and includes a voltage clamp (50) and series inductor-capacitor resonant circuit (46), so that the resonant circuit provides a low series impedance when applied with a signal at the operating frequency of the input signal applied by the generator but provides a high series impedance when experiencing a signal of a different frequency indicative of a system fault.
    Type: Grant
    Filed: November 17, 2000
    Date of Patent: August 21, 2001
    Assignee: Smiths Aerospace, Inc.
    Inventor: Charles E. Bogert
  • Publication number: 20010003500
    Abstract: Electrical protection device for a railroad vehicle, including electrical energy consuming units 6, 7 and electrical power supply means 1 to 5, electrical energy being supplied on at least two liner electrically separated from the ground formed by the vehicle as a whole, in particular its chassis and the electrically conductive parts connected to it. The electrical protection device includes detector means 50 for detecting a short circuit alternating current flowing from one of the two power supply lines to ground, to detect any short circuit between the other power supply line and ground.
    Type: Application
    Filed: December 6, 2000
    Publication date: June 14, 2001
    Inventors: Alain Cheze, Bernard Macor
  • Patent number: 6236546
    Abstract: A system is disclosed for verifying the operativeness of a crowbar circuit which normally protects an electrical device in a series circuit with a power supply. The crowbar circuit includes means for sensing fault current in the series circuit and a crowbar switch responds to the sensing means for protecting the electrical device by directing the fault current away from the electrical device. The system includes verification testing means including a fuse and actuatable pneumatic switch connected together in series for, when said pneumatic switch is actuated, providing a short circuit across the crowbar switch to verify the operativeness of the crowbar circuit which, if not operative, causes the fault current to flow through and blow out the fuse.
    Type: Grant
    Filed: August 16, 1999
    Date of Patent: May 22, 2001
    Assignee: Harris Corporation
    Inventors: Joseph David Blickhan, James Bruce Pickard
  • Patent number: 6178075
    Abstract: An electronic module comprising a power supply conductor coupled to one or more electromechanical actuators to supply operable power to the electromechanical actuators. The electronic module also includes a moisture sensor positioned to sense moisture intrusion into the module. Further, the electronic module comprises a first transistor responsively coupled to the moisture sensor, the first transistor coupled to draw current from the power supply conductor when the first transistor is in a conductive state. In addition, the electronic module includes a second transistor responsively coupled to the first transistor and in turn controllingly coupled to the first transistor.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: January 23, 2001
    Assignee: Visteon Global Technologies, Inc.
    Inventors: Mark Andrew Glinka Endicott, Vincent Colarossi, Viren Babubhai Merchant
  • Patent number: 6094013
    Abstract: A circuit arrangement for limiting the current at make for a transformer wherein, in order to avoid the current peak at make when switching a transformer on, resistors are connected between operating voltage and the primary winding of the transformer. A test winding at the secondary side of the transformer is connected via a rectifier to the supply input of a contactor, so that the switches of the contactor close after the transformer is turned on and the resistors therefore no longer lie between operating voltage of the primary winding. PTC-resistors connected in series with the resistors assure that the resistors are not overloaded by the high-operating current of the transformer if the switches do not switch.
    Type: Grant
    Filed: December 2, 1998
    Date of Patent: July 25, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventors: Hugo Goller, Klaus Hoffmann
  • Patent number: 6031342
    Abstract: An electronic ballast for a fluorescent lamp which includes a frequency sweep circuit for driving a ballast controller IC at different operating frequencies depending on the operating mode of the fluorescent lamp. The sweep circuit monitors the operating mode of the lamp (e.g., preheat, ignite, running, shutdown) and automatically generates an appropriate variable voltage offset for controlling the lamp. The offset is added to a constant voltage supplied to an input of the ballast controller IC, resulting in a corresponding change in the frequency output by the ballast controller IC (and thus the lamp power). The electronic ballast also includes fault protection logic which monitors signals from the lamp resonant circuit and shuts down the ballast in the event of a fault condition. The fault protection logic also resets the frequency sweep circuit so that the lamp can restart automatically when the fault is corrected.
    Type: Grant
    Filed: February 12, 1998
    Date of Patent: February 29, 2000
    Assignee: International Rectifier Corporation
    Inventors: Thomas J. Ribarich, John Parry
  • Patent number: 6028470
    Abstract: An integrated circuit comprising a power transistor and a circuit arrangement. The circuit arrangement is thermally coupled to the power transistor and operates in a temperature-dependent fashion. The integrated circuit includes a pnp or npn transistor with a temperature dependent resistor coupled between the base and emitter of the transistor. The off-state current of the transistor changes as a function of temperature and initiates a change in a base current of the power transistor.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: February 22, 2000
    Assignee: Robert Bosch GmbH
    Inventors: Hartmut Michel, Christian Pluntke
  • Patent number: 5959816
    Abstract: A voltage regulator circuit includes a circuit input and a circuit output for coupling to a load. A circuit interrupt element is coupled between the input and the load for breaking the circuit between the input and the load. A sensing circuit coupled to the output senses when a signal applied to the load exceeds a defined limit. A trigger circuit coupled to the sensing circuit causes the circuit interrupt element to trip when the sensing circuit senses a signal which exceeds the defined limit.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: September 28, 1999
    Assignee: Anthony, Inc.
    Inventors: Gary Wood, Bernard Feldman
  • Patent number: 5923515
    Abstract: A protection device for an electrical circuit comprises a housing assembly, a fuse support structure that is comprised of a conductive material and that can be coupled to the housing assembly, a main fuse that can be mounted to the fuse support structure to receive a flow of current therefrom and a trip fuse mechanically mounted to the main fuse by electrical contacts. The electrical contacts not only secure the trip fuse to the main fuse, but also provide a conductive path across the main fuse and through the trip fuse. In some embodiments, a momentary switch may be coupled to the trip fuse. In such instances, the trip fuse is configured to activate the momentary switch when a predetermined excessive current flows through the trip fuse and may be electrically connected to a current indicator that indicates when the excessive current flows through the trip fuse.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: July 13, 1999
    Assignee: Lucent Technologies Inc.
    Inventors: Gerald W. Eubanks, Michael C. Steeves
  • Patent number: 5892647
    Abstract: An overcurrent detection circuit detects an overcurrent in a current path accurately and sensitively. The overcurrent detection circuit includes a first resistance element connected between first input and output terminals of the current path; a second resistance element connected to the first input terminal; a differential amplifying device connected to the first output terminal and the second resistance element; and a proportional-current output device connected to the second resistance element in series and to an output terminal of the differential amplifying device. The proportional-current output device receives an output signal from the differential amplifying device to output a proportional current with a magnitude proportional to a current flowing through the first resistance element.
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: April 6, 1999
    Assignee: Fuji Electric Co., Ltd.
    Inventor: Kimiyoshi Mizoe
  • Patent number: 5856902
    Abstract: The earth leakage breaker of the invention includes a first comparator; a second comparator connected to the first comparator; a third comparator having a threshold higher than the threshold of the first comparator for distinguishing a leakage current from the grounding current caused by a lightning surge or by the heavy ground fault; a monostable multivibrator triggered by the output of the third comparator for forming a time gate of a predetermined period; a counter for detecting a pulse outputted from the first comparator to distinguish whether the grounding current is caused by the lightning surge or by the heavy ground fault; and a trip signal generator circuit for outputting a trip signal in the case of leakage and heavy ground fault. The earth leakage breaker facilitates avoiding unnecessary breaking of the impulsive grounding current caused by the lightning surge.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: January 5, 1999
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Takashi Hashimoto, Kiyoshi Tanigawa, Shoji Sasaki, Katsumi Watanabe
  • Patent number: 5838043
    Abstract: A circuit for protecting a bonding pad of a semiconductor device from ESD voltages is located under the pad to permit the space otherwise used for a protection circuit to be used for normal operating components. The protection circuit has a compact layout that provides maximum ability to handle an ESD current within this limited space. The semiconductor structure for the circuit has separate parts for two SCR circuits, one for each polarity of ESD current. Each SCR circuit comprises two symmetrical SCR structures.
    Type: Grant
    Filed: April 29, 1997
    Date of Patent: November 17, 1998
    Assignee: United Microelectronics Corp.
    Inventor: Lee Chung Yuan
  • Patent number: 5821740
    Abstract: A DC-to-DC converter includes a pulse width modulation circuit for modulating a switch to produce current pulses having at least a minimum pulse width to thereby control an output voltage to the load. The converter also includes a current limit determining circuit for determining when a desired peak current is no longer sufficient to maintain a desired output voltage thereby defining a current limit condition. In addition, the pulse width modulating circuit, when operating at the minimum pulse width, thereby defines a minimum pulse width condition. Accordingly, the converter preferably further includes an over-current determining circuit for determining an over-current condition responsive to the minimum pulse width condition being reached during a current limit condition. The converter may turn off the switch responsive to an over-current condition. A blanking signal may be used to clamp a comparator and established a minimum pulse width.
    Type: Grant
    Filed: February 14, 1997
    Date of Patent: October 13, 1998
    Assignee: Harris Corporation
    Inventors: Robert G. Hodgins, Charles E. Hawkes, Michael M. Walters
  • Patent number: 5805399
    Abstract: Apparatus for detecting series arcs and output load faults in high frequency luminous tube power supplies and ballasts including wideband ringing and detector circuits for collecting the intense high frequency, pre-plasma noise energy associated with the initial avalanche phase of high frequency arc formation and a transient suppressor for delaying the triggering of power supply shut-down for up to the duration of the arc avalanche phase. Plural detectors for increased sensitivity and reliability over a variety of arc locations may be employed. Dual purpose detector input probes serve as over-voltage corona generators.
    Type: Grant
    Filed: September 6, 1996
    Date of Patent: September 8, 1998
    Assignee: Everbrite, Inc
    Inventor: David R. Pacholok
  • Patent number: 5757601
    Abstract: A short circuit protection system that reacts to a voltage across an electrical load to prevent overdissipation of a semiconductor switch in the event of a short circuit. The system includes a capacitor having a charge state. When the capacitor is charged, the electrical load is turned ON via a transistor. The system automatically latches the electrical load ON until a short circuit occurs or until the capacitor discharges. When a short circuit occurs, the system automatically turns the load OFF.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: May 26, 1998
    Assignee: Ford Motor Company
    Inventor: Harold Ryan Macks
  • Patent number: 5751051
    Abstract: A semiconductor device has a semiconductor chip which is divided into a plurality of separate regions. In each of these regions, there are provided a plurality of common discharge lines which are independent from one another, a plurality of first bonding pads which are connected directly to the respective common discharge lines, a plurality of second bonding pads which are not connected directly to the common discharge lines, a plurality of protective elements which are connected between the second bonding pads and the common discharge lines, and an inner lead for discharging which is directly connected to the first bonding pads and is bonded to a surface of the semiconductor chip. In all embodiments of the invention. More than one common discharge line is provided. This arrangement permits the reduction of the chip area thus enhancing design freedom and improving electrostatic breakdown characteristics.
    Type: Grant
    Filed: October 16, 1997
    Date of Patent: May 12, 1998
    Assignee: NEC Corporation
    Inventor: Kiminori Hayano
  • Patent number: 5737170
    Abstract: The base of a thermal shutdown bipolar transistor having a V.sub.BE(on) which decreases with increasing temperature is biased with a bias voltage V.sub.PTATbias which increases proportionally with increasing absolute temperature. By supplying the base of the thermal shutdown transistor with a bias voltage V.sub.PTATbias which increases with increasing temperature rather than a bias voltage that remains constant or decreases with increasing temperature, the temperature at which the thermal shutdown transistor turns on is made more predictable and the thermal shutdown transistor is made to turn on more sharply at a desired thermal shutdown temperature. The bias voltage V.sub.PTATbias may be generated by driving a current which increases proportionally with increasing absolute temperature across a resistor. Current sources employing feedback control loops are disclosed for generating such a current. Startup current sources are disclosed for starting control loop operation.
    Type: Grant
    Filed: September 27, 1994
    Date of Patent: April 7, 1998
    Assignee: Micrel, Inc.
    Inventor: James C. Moyer
  • Patent number: 5723960
    Abstract: An opening/closing control apparatus detects an overload placed on a movable member of a vehicle such as a sunroof and a power window while it is sliding. Further, it prevents overload detecting operation (reversing motion) from being made by a cause other than an overload. A control processor circuit compares a driving current value of a motor detected at predetermined intervals with a preset current value and corrects an overload threshold value to a threshold value of higher value when the driving current value detected when a first predetermined time period has passed after the start of the motor does not exceed the preset current value. Thereafter, the control processor circuit determines that an overload has occurred when a change in the driving current value has exceeded the overload threshold value.
    Type: Grant
    Filed: August 8, 1995
    Date of Patent: March 3, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kouichi Harada
  • Patent number: 5710689
    Abstract: A protection circuit prevents snapback events in MOS transistors associated with semiconductor or micromechanical structures, such as ink-jet ejectors. A bulk electrode associated with the MOS transistor is monitored for unusual high voltages which are consistent with an impending snapback event. The voltage on the bulk electrode is then used to turn on the control transistor which connects the gate of the MOS transistor to ground and thereby protects the device.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: January 20, 1998
    Assignee: Xerox Corporation
    Inventors: Juan J. Becerra, Sophie V. Vandebroek
  • Patent number: 5703746
    Abstract: Wiring harnessess are current feedback paths from the loads to a battery, thereby forming a closed-circuit. For each load, there are provided a current detector and a current control; each current detector compares the current input to a junction box to the output current from the corresponding load via a corresponding wiring harness, and outputs a normal state signal when the two currents are equal. When the input and output currents are at variance with each other, it outputs an abnormal state signal. Each current controller causes, upon receipt of the normal state signal, the input current to flow into the corresponding load along normal current path; upon receipt of the abnormal state signal, the input current is directed to flow to a current cutoff which includes a thermal device which is disposed in parallel with the current path and whose resistance value changes with temperature, thereby cutting off the flow of current to the load.
    Type: Grant
    Filed: February 16, 1996
    Date of Patent: December 30, 1997
    Assignee: Sumitomo Wiring Systems, Ltd.
    Inventors: Takahiro Onizuka, Yuuji Saka
  • Patent number: 5672918
    Abstract: A "blink" technique, analogous to a person blinking at a flash of bright light, is provided for mitigating the effects of single event current latchup and prompt pulse destructive radiation on a micro-electronic circuit. The system includes event detection circuitry, power dump logic circuitry, and energy limiting measures with autonomous recovery. The event detection circuitry includes ionizing radiation pulse detection means for detecting a pulse of ionizing radiation and for providing at an output terminal thereof a detection signal indicative of the detection of a pulse of ionizing radiation. The current sensing circuitry is coupled to the power bus for determining an occurrence of excess current through the power bus caused by ionizing radiation or by ion-induced destructive latchup of a semiconductor device.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: September 30, 1997
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Joseph Robert Kimbrough, Nicholas John Colella
  • Patent number: 5670936
    Abstract: A power controller (10) for supplying power to a power distribution network (N) in which power from a polyphase source (G) is routed to using equipment (E) connected to the network through the power controller. A plurality of solid-state power devices (82) switch each separate phase of the polyphase power to the equipment. A firing circuit (14) controls gating of the switches to route the power. Fuses (F) are connected between the switches and the using equipment to interrupt power flow to the equipment if excessive current begins to be drawn. A con, roller (20) controls a shutdown sequence employed by the controller to eliminate current spiking at shutdown. The various components are housed in an enclosure (22) which includes a mounting structure (56) for mounting the aforesaid components. A cooling system (26) employs a fan (88) for directing air flow through the mounting structure to cool the components.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: September 23, 1997
    Assignee: Emerson Electric Co.
    Inventors: Wayne S. Estes, Carl D. Russell
  • Patent number: 5640293
    Abstract: A high-current, high-voltage solid state switch includes at least one solid state switching component connected to control circuitry configured into a single package. In the preferred embodiment, the switching component includes a power field effect transistor, and the control circuitry includes control logic, temperature sense and overcurrent circuits supported in an adjacent, coplanar relationship. Parallel coupled transistors are used for higher current embodiments.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: June 17, 1997
    Assignee: Ice Corporation
    Inventors: William H. Dawes, Arthur R. Vaughan
  • Patent number: 5629824
    Abstract: The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.
    Type: Grant
    Filed: July 27, 1993
    Date of Patent: May 13, 1997
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Richard A. Rankin, Dale K. Kotter
  • Patent number: 5606482
    Abstract: A solid state circuit breaker which provides high voltage isolation between a control circuit and a power source is described. The circuit breaker comprises a receiver for providing a control signal in response to a transmitter that is electrically isolated from the receiver, a solid state switch that closes in response to the control signal thereby allowing a load current to flow through the switch, a current sensor for measuring the load current, and an inhibit circuit responsive to the current sensor for inhibiting the control signal when the load current exceeds a predetermined magnitude thereby opening the switch without adjusting the transmitter. After opening the switch, the inhibit circuit is responsive to the transmitter for allowing the control signal thereby closing the switch.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: February 25, 1997
    Assignee: Lucent Technologies Inc.
    Inventor: Steven B. Witmer
  • Patent number: 5587862
    Abstract: A Ground Fault Interrupter ("GFI") combined with a plug-receiving receptacle is mounted on a plastic bucket. The bucket is additionally configured with a weathertight opening through which a three prong male end of a pigtail electrically connected to the GFI/receptacle unit may pass. A resealable lid provides a weathertight covering for the bucket so that the combination is functional during field use or for final storage for user transport of tools and other electrical apparatus. The device is optionally configured with a removable, storable, pedestal pole-mounted light assembly. A pedestal light support flange is attached to the interior base of the bucket, and container-sized pole sections substantially the same interior clearance height of the container are available for assembling the light pole when needed by a user. The light is powered by the GFI/receptacle unit carried by the bucket.
    Type: Grant
    Filed: July 13, 1995
    Date of Patent: December 24, 1996
    Inventor: William D. Frank, Sr.
  • Patent number: 5587864
    Abstract: A three-phase electrical system includes an interrupt controller. The interrupt controller protects against inadvertent current flow between a phase conductor and ground and between phase conductors. The interrupt controller measures the voltage across a series connection of current transformers disposed about various phase conductors. If an inadvertent current path exists between one of the phase conductors and ground or between two of the phase conductors, the interrupt controller interrupts the current flow in the phase conductors. Additionally, a single-phase electrical system with a hot conductor and a neutral conductor includes an interrupt controller. The interrupt controller protects against inadvertent current flow between the hat conductor and ground and between the hot conductor and the neutral conductor. The interrupt controller measures the voltage across a series connection of current transformers disposed about the hot and neutral conductors.
    Type: Grant
    Filed: April 11, 1994
    Date of Patent: December 24, 1996
    Assignee: Ford Motor Company
    Inventors: Allan R. Gale, Craig B. Toepfer
  • Patent number: 5574378
    Abstract: A non-ferrous current sensor is used to continuously measure the charging current magnitude in step-graded foil and paper insulation systems and capacitive insulation systems used on high voltage measurement and control apparatus such as instrument transformers and on the condenser bushings of power transformers and circuit breakers. The low voltage measured signal is conditioned by an electronic circuit such that it modulates a DC signal in a system current control loop to provide continuous remote monitoring and alarm functions. Remote power is supplied to the sensor and conversion circuits through the current loop. The sensor detects changes in the charging current through the insulation ground conductor, indicating the degradation of the dielectric properties between the foil layers. The sensor and associated electronic circuitry are enclosed in a housing adaptable to be used with a capacitance tap common to high voltage measurement and control apparatus.
    Type: Grant
    Filed: December 15, 1994
    Date of Patent: November 12, 1996
    Assignee: Square D Company
    Inventors: Thomas J. Meyer, Nicholas S. Powers
  • Patent number: 5537026
    Abstract: A power controller (10) and a method for supplying power to a power distribution network (N) in which power from a polyphase source (G) is routed to using equipment (E) connected to the network through the power controller. A plurality of solid-state power devices (82) switch each separate phase of the polyphase power to the equipment. A firing circuit (14) controls gating of the switches to route the power. Fuses (F) are connected between the switches and the using equipment to interrupt power flow to the equipment if excessive current begins to be drawn. Circuit breakers (74) are connected between the power source and the switches to interrupt current flow to the equipment if excessive current is drawn. A control unit (20) controls operation of the controller. The firing circuit includes a master firing unit (164a) and a slave firing unit (164b).
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: July 16, 1996
    Assignee: Emerson Electric Co.
    Inventors: Wayne S. Estes, Carl D. Russell
  • Patent number: 5526216
    Abstract: In a circuit configuration for the shutoff of a semiconductor component in the event of excess current, the semiconductor component has gate and cathode terminals and is controlled by the field effect. A controllable switch is connected between the gate and cathode terminals and is made conducting by a control signal. A device controls the controllable switch to a range of high on-state DC resistance when there is excess current and a shutoff signal is simultaneously present.
    Type: Grant
    Filed: September 9, 1994
    Date of Patent: June 11, 1996
    Assignee: Siemens Aktiengesellschaft
    Inventors: Sven Konrad, Klaus Reinmuth, Hans Stut
  • Patent number: 5519264
    Abstract: A method and apparatus for preventing current inrush upon the application of power to a load includes the steps of applying a first increasing DC voltage from a voltage source to the load through a negative temperature coefficient device having a first terminal coupled to the voltage source and a second terminal coupled to the load and after a preselected period of time, bypassing said first and second terminals via a bypass circuit and coupling the increasing voltage to the load through the bypass circuit.
    Type: Grant
    Filed: March 27, 1995
    Date of Patent: May 21, 1996
    Assignee: EMC Corporation
    Inventors: Christopher A. Heyden, Donald R. Watson
  • Patent number: 5485342
    Abstract: An abnormal current cut off circuit for creating a circuit break when an abnormal current flows in a circuit such as a print head driver circuit for a printer. When a driver section 3 is being driven by a power supply circuit 1, the power supply is provided to a driver circuit 2 which drives the driver section 3 via a transistor 5 which is connected in the power supply line and which is turned on by a transistor 7. When the device goes into a standby state, the transistor 5 is turned off, so that the current is supplied to the carriage motor a and the Line feed motor b within the driver section 3 via the fuse 4 and the diode 6 which are connected in parallel with the transistor 5. If an abnormal current then flows during the standby state, the fuse 4 will be broken, and transistor 7 will be turned off so that transistor 5 will also be turned off which ensures that the power supply line is cut completely.
    Type: Grant
    Filed: July 28, 1993
    Date of Patent: January 16, 1996
    Inventors: Koichi Sugino, Nobuhiro Michimoto
  • Patent number: 5424898
    Abstract: A drive circuit for the interior, and one or more of the exterior, mirrors in a vehicle mirror system provides a drive signal to each of the mirrors to establish the reflectance level of that mirror. Circuit protection is provided to sense a fault condition on one of the electrical conductors extending to the exterior mirrors and to take corrective action in response to a fault condition. The circuit protection may also respond to a fault condition in the electrical supply of the drive circuit and take suitable corrective action. In certain embodiments, each mirror in the mirror system is responsive to one of a plurality of output amplifiers, which is responsive to a distinct desired reflectance signal level in order to color that mirror to a reflectance level that is distinct from that of the other mirrors.
    Type: Grant
    Filed: August 8, 1994
    Date of Patent: June 13, 1995
    Assignee: Donnelly Corporation
    Inventors: Mark L. Larson, Desmond J. O'Farrell
  • Patent number: 5420396
    Abstract: A heating apparatus comprising a heating member, energization element for energizing said heating member, a temperature detection member for detecting a temperature of said heating member, a first switching element for turning on/off energization by said energization means on the basis of the temperature detected by said temperature detection member, abnormal current detection element for detecting an abnormal current flowing through said heating member, a second switching element for turning off energization by said energization element, and energization stop member for operating said second switching element to turn off energization.
    Type: Grant
    Filed: February 26, 1992
    Date of Patent: May 30, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshiyuki Itoh, Toshihiko Inuyama, Takeji Gima, Hiroshi Hashimoto, Hiromichi Yamanaka, Masanori Ishizu
  • Patent number: 5414586
    Abstract: A superconducting current limiting device for limiting overcurrent flowing in a load. The device includes a current limiter with a first superconducting coil, a second superconducting coil arranged coaxially with the first superconducting coil so as to have a negative magnetic coupling condition, and a third superconducting coil arranged coaxially with the first and second superconducting coils so as to have a negative magnetic coupling condition with the second superconducting coil and so as to have a positive magnetic coupling condition with the first superconducting coil. The first and second superconducting coils are electrically connected in series. The device includes a high speed switch connected electrically in series with the third superconducting coil to form a series circuit. The series circuit is electrically connected in parallel with the second superconducting coil.
    Type: Grant
    Filed: April 20, 1993
    Date of Patent: May 9, 1995
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukushi Hara, Takeshi Ohkuma, Kazuyuki Tsurunaga, Daisuke Ito, Takamitsu Tada
  • Patent number: 5394287
    Abstract: A TSD (8) is provided in the vicinity of an IGBT (1), and reference voltages (VR1 to VR5) are provided to the negative inputs of comparators (51 to 55) as a function of a temperature detection signal (S8). A sense terminal (3) of the IGBT is connected to the positive inputs of the comparators (51 to 55) in common. An output signal (S51) of the comparator (51) and output signals (S72 to S75) of signal judging circuits (72 to 75) having received the output signals (S52 to S55) are applied to the input of an NOR gate (6) for on/off control of the IGBT. The signal judging circuits (72 to 75) normally output an L-level judgment signal (S7) and output an H-level judgment signal (S7) when the input signal is at the H level for periods of time that are not shorter than allowable durations (.DELTA.t2 to .DELTA.t5 ), respectively. This provides an overcurrent protective device for a power device which performs overcurrent protective operation adapted for a practical safe operating area of the power device.
    Type: Grant
    Filed: January 29, 1993
    Date of Patent: February 28, 1995
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Hiroshi Sakata, Masanori Fukunaga
  • Patent number: 5285346
    Abstract: A control circuit for protecting a power device has been provided. The control circuit has a thermal shutdown circuit for activating a first SCR when the temperature of the control circuit exceeds a predetermined temperature. Additionally, the control circuit has a DSAT detection circuit for activating the first SCR in response to an external signal. The first SCR is coupled across an input terminal and the common terminal of the control circuit. When the first SCR latches, it functions to subsequently latch a second SCR that is coupled across the output and common terminals. The second SCR functions to rapidly discharge the voltage appearing across the output and common terminals.Additionally, the control circuit includes an input level sensitive circuit which may be utilized to deactivate various circuitry depending upon the current level of an input signal supplied to the control circuit.
    Type: Grant
    Filed: December 13, 1991
    Date of Patent: February 8, 1994
    Assignee: Motorola, Inc.
    Inventors: Robert B. Davies, David F. Mietus, Paul T. Bennett
  • Patent number: 5162965
    Abstract: A high-speed high-voltage FET current interrupter which opens the cathode circuit of microwave tubes when internal tube arcing occurs. By removing the detrimental fault current which causes degradation to the microwave tube body and grid, the longevity of the microwave tube and the pulse energy storage capacitor is greatly increased over those transmitters which use dissipative crow bar circuits. Even more important is that the transmitter reset time after an arc occurs is orders of magnitude faster than transmitters using crow bars or primary power interrupters when arcing occurs--an important feature when engaged in a "dog fight".
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: November 10, 1992
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Walter E. Milberger, Franklin B. Jones, Charles S. Kerfoot
  • Patent number: 5150286
    Abstract: The invention icludes a device for protecting electronic circuitry from damage, especially damage resulting from high neutron flux density produced by a nuclear explosion. The invention protects the circuitry by disabling its power supply system upon detection of the nuclear event. The power supply system is disabled both by short-circuiting the main power supply, which provides control voltages to various subsidiary powert supplies, and by short-circuiting all the output filter capacitors in the system, which may have a substantial residual charge. The invention periodically and automatically attempts to re-start the power supply system, but the system can be re-started only if the nuclear event detector is not actuated. The circuit made according to the invention is entirely analog, and therefore does not depend, for its operation, on the continued functioning of the circuitry to be protected.
    Type: Grant
    Filed: March 12, 1991
    Date of Patent: September 22, 1992
    Assignee: Performance Controls, Inc.
    Inventors: Joseph G. Venditto, Jr., James P. Detweiler
  • Patent number: 5119262
    Abstract: A protection circuit against an excessive current in a flyback transformer which supplies a high voltage to a CRT. A fuse and current detecting resistor are inserted on the line which supplies a current to the primary winding of the flyback transformer. The intermediate point of the primary winding and the node of the fuse and current detecting resistor are connected by a semiconductor switching element which becomes conductive when the voltage across the current detecting resistor reaches a certain high voltage. Accordingly, if an excessive current flows in the flyback transformer, the thyristor turns on, causing the fuse to be blown by the large current, whereby the current supply to the flyback transformer can be shut off.
    Type: Grant
    Filed: July 26, 1989
    Date of Patent: June 2, 1992
    Assignee: Murata Mfg. Co., Ltd.
    Inventor: Hiroshi Ikeuchi