Abstract: A device for controlling the power supply to the electric motor of a starter for a vehicle having a power switch connected in series with the electric motor, units for controlling the power switch, and an auxiliary switch which shorts the electric motor when the power switch is opened, where the auxiliary switch is a static electronic component.

Abstract: An improvement in a starting system for an electric motor, which drives a hermetic compressor of refrigeration and comprises a main winding (1), and an auxiliary winding (2), which are energized by an electric current source (3), through a hermetic terminal (40) affixed to the outside of the compressor shell, the auxiliary winding (2) having a terminal connected to the electric current source (3) through a starting device (10) mounted inside the compressor shell and in series with a fusible element (20) to be opened when submitted to an electric current, in order to definitively interrupt the energization of the auxiliary winding (2) by means of the starting device (10), said hermetic terminal (40) being designed to receive an external starting device (50), in order to promote the selective connection between said other terminal of the auxiliary winding (2) and the electric current source (3) upon the definitive opening of the circuit defined by the fusible element (20) and the starting device (10).

Abstract: A method and apparatus for controlling an electric motor pump. The method includes the acts of providing an AC power signal having a positive half cycle and a negative half cycle, measuring the voltage of the AC power signal and generating a first two-state output signal that is in a logic high state when the measured voltage is on the positive half cycle and that is in a logic low state when the measured voltage is on the negative half cycle, and measuring the current of the AC power signal and generating a second two-state output signal that is in logic high state when the measured current is on the positive half cycle and that is in a logic low state when the measured current is on the negative half cycle.

Abstract: A starting device for electric motors which is designed to be fitted to compressor motors or the like, and includes a PTC resistor in series with a relay inserted between the line and the motor start winding.

Abstract: A CPU operates as an abnormality detection circuit for detecting an ON-state failure of FETs forming a motor drive circuit and a failure of terminals of the motor. The abnormality detection circuit inputs a motor supply voltage, a motor left-terminal voltage and a motor right-terminal voltage from a power supply voltage detection circuit, a motor left-terminal voltage detection circuit and amotor right-terminal voltage detection circuit, respectively.

Abstract: A motor start switch includes a temperature responsive resistor element and a cutout switch electrically connected in series with a start winding of an electric motor. The cutout switch is in thermal contact with the temperature responsive resistor element so that heat from the temperature responsive resistor element is transferred to a bimetal element in the cutout switch, causing the bimetal element to open the switch. Heat from a motor overload protector provides heat to maintain the bimetal element in an open position. As heat to operate the temperature responsive resistor element is obtained from existing circuit elements, the efficiency rating of the motor is unaffected.

Abstract: In control apparatus and method for an electric vehicle, when the motor is determined to be locked during a run of the vehicle on an ascending slope, a limitation torque .tau.r of the motor as a function of a maximum value T.sub.JMAX of estimated junction temperatures of respective switching devices of an inverter circuit is determined, an output torque .tau.L for the motor to be escaped from the locked state is calculated as .tau.L=.tau..GAMMA.-.DELTA..tau., wherein .DELTA..tau. denotes a displacement torque, .DELTA..tau.=.DELTA..tau.+A when .tau.r<.tau.c and a phase domain of the motor determined on the basis of a magnetic pole position .theta. is the same as the previous one and .DELTA..tau.=0 when .tau.r.gtoreq..tau.c and the phase domain is not the same as the previous one.

Abstract: A method and apparatus for reducing winding failures in electric machines resulting from the application of high frequency or high dV/dt voltage pulses or voltage signals to the phase windings of the machine in which an inductive element is provided between the source of the high-frequency or high dV/dt pulses and the phase winding to absorb a portion of the voltage stresses on the phase windings that result from the application of the high-frequency or high dV/dt pulses to the machine.

Abstract: The present invention involves a refrigeration system. The refrigeration system comprises an electrical compressor motor, a line adapted to be connected to an electrical power line and a thermostat control circuit. The thermostat control circuit comprises a thermostat responsive logic circuitry coupled to a temperature sensor associated with the compressor and a solid state motor control circuit. The solid state motor control circuit includes a relay circuitry, power switch circuitry, compressor starting circuitry with an overload timer, high voltage protection circuitry, under voltage protection circuitry and run current limiting circuitry. The relay circuitry includes an optical coupler and triac to provide line voltage to the compressor through a start resistor. The power switch circuitry includes a pair of SCR's connected in parallel as a switch to allow current to flow through the compressor.

Abstract: An electric vehicle control device controls an induction motor with a VVVF inverter. A first calculation means calculates a rotor-resistance correction value of the induction motor based on a torque current instruction value for vector control of the induction motor and an actual torque current value. A second calculation means calculates a corrected rotor-resistance value based on the rotor-resistance correction value and a reference rotor-resistance value. A third calculation means calculates an estimated rotor temperature of the induction motor based on the corrected rotor-resistance value, the reference rotor-resistance value, and a temperature coefficient determined by a material of a rotor. The thermal condition of the induction motor is thus monitored in real time without installing a temperature sensor on the induction motor.

Abstract: A motor whose stator is equipped with a main winding (DP) and with an auxiliary winding which consists of two half-windings (B1, B2) that are wound in opposite directions and is supplied through a full-wave rectifier (GR) and by means of two commutating switches (T1, T2) controlled by a control circuit (COM) which alternately closes the switches at a frequency equal to the frequency of the supply voltage. The motor comprises, in parallel with the half-windings, at least one device (DAP) which limits the voltage across the terminals of the switches when they are opened, to a value higher than the supply voltage.

Abstract: The present application discloses a system and associated method for lowering heat dissipation created by running a motor. The system comprises a voltage regulator, the motor, and a controller. The voltage regulator is connected to a supply voltage and has an output voltage with an associated output current dependent upon impedance of the system. The motor, which may be AC or DC, is driven by the output voltage and an output current at a current running speed. The controller controls the supply of the output voltage and associated output current to the motor toward varying the current running speed of the motor while minimizing the power dissipated throughout the system.

Abstract: The invention relates to a single-phase induction motor comprising a main winding, an auxiliary winding which is arranged so that an electrical angle of the auxiliary winding is different from that of the main winding, a plurality of driving capacitors which are connected to the auxiliary winding, a relay for controlling on/off of the driving capacitor in response to the driving load, and a rotor having apertures on the gap side of the slots. The invention further relates to a rotor assembling apparatus comprising a bush to which a rotor core assembly is inserted for die-casting, wherein a clearance between said bush and said rotor core assembly is narrower to the extent that said rotor core assembly can be taken out after die casting; and a core band having a clearance between the core band and the bush in the circumferential direction of said bush, said core band is engaged into said bush so that movement in the axis direction is restricted.

Abstract: An inverting amplifier circuit generates a comparison voltage by comparing a smoothed voltage of a voltage across a semiconductor switching element and a setting voltage that is generated by device of a voltage setting volume. An operational amplifier generates a drive signal by comparing the above comparison voltage and a triangular voltage. Negative feedback is effected so that the setting voltage becomes equal to the smoothed voltage, which is inversely proportional to the rotation speed of a DC motor.

Abstract: The invention concerns an improved system for windshield wipers in vehicles. An induction motor is used, in which speed is accurately controlled by controlling frequency of power supplied to the motor. The induction motor may be of the consequent-pole type, which ordinarily does not produce sufficient torque. Addition of (a) auxiliary tooth slotting and (b) skew has raised the torque produced to acceptable levels.The invention includes a control system, which senses excess load on the motor, which occurs as the windshield dries, and reduces motor speed, subject to a minimum, in response.

Abstract: A starting circuit for a single-phase induction motor having a start capacitor, an auxiliary or start winding, and a run winding includes user adjustable pick-up voltage means to allow a user to select a pick-up voltage in the field to correspond to the pick-up voltage of a particular induction motor such that a relay disconnects the start winding from the power supply when the start winding voltage exceeds the selected pick-up voltage. Protective circuitry is provided including a timing circuit to protect from missetting of the pick-up voltage or when the motor will not start for any reason and a relay current circuit to control the current flowing in the relay to protect from high voltage overloading.

Abstract: A single phase induction motor includes a start winding, a run winding coupled in parallel with the start winding, a start switch, and a run switch. A control circuit is provided for selectively supplying voltage to the start and run windings. A current sensor is coupled to the control circuit and the start and run windings for estimating the temperature rise of the motor and turning the motor off if overheated. An alternating voltage having a plurality of 360.degree. cycles can be continuously applied to the run winding through the run switch. The alternating voltage is repetitively applied through the start switch to the start winding in the range of 45.degree. to 135.degree. into each respective one of the plurality of cycles and ending at approximately 180.degree. into each respective cycle and beginning in the range of 225.degree. to 315.degree. into each respective cycle and ending at approximately 360.degree. into each respective cycle until the motor is running at a speed close to synchronous speed.

Abstract: When power is sequentially supplied to the phase coils of a brushless DC motor, the rotor of the brushless DC motor is rotated. At this time, a voltage is induced in one of the phase coils to which power is not supplied. The rotational position of the rotor is detected from the induced voltage. The switching timing of power supply to the phase coils is determined in accordance with the detected rotational position. When a service operation mode switch is operated, a service operation is executed, and power supply to the respective phase coils is forcibly switched at a predetermined frequency. A failure can be diagnosed during this service operation.

Abstract: A method for reducing motor start-up current in an electric motor control system. The method first prevents flow of current through the motor while slowly charging a parallel capacitor. Then, the motor control voltage is reduced and current is switched through the motor. The motor control voltage remains reduced until the motor starts turning. After the motor starts turning, the control voltage is slowly increased as the motor accelerates, limiting the current from the power supply.

Abstract: A circuit for boosting the power output of a motor in which a sensor stage, preferably a voltage divider, is coupled to comparator stage, preferably a reverse biased to a diode, which in turn is coupled to a power boost stage, preferably a relay and switched capacitance associated therewith, such that upon sensing of excess loading of the motor, the capacitance is switched across the output of the motor.

Abstract: An emergency power circuit powers an induction motor which has at least first and second windings. The motor is normally operating at a normal speed determined by connection to commercial frequency power line, but which is subject to failure. During failure the emergency power circuit is used to supply emergency power from a DC storage battery. An inverter is supplied by the battery and has an output connectable to the motor. A control circuit for the inverter establishes a first frequency to run the motor at a running speed which is considerably less than the normal speed. Single, two-phase and three-phase systems are disclosed as well as a soft start system to start the motor at about one-fourth speed and run it at one-half speed. Preferably a high frequency oscillator is used with the frequency divided dozen to operate the motor at a speed below normal 60 Hz energization speed.

Abstract: The present invention provides a drive and control circuit for a single phase, brushless DC motor. The drive and control circuit includes an integrated circuit having a maximum rated voltage lower than the maximum net voltage of the overall circuit. Internal transistors in the integrated circuit are used to drive the emitters of two external power transistors which are connected to the windings of the DC motor. In this manner, a relatively inexpensive integrated circuit can be used to drive and control a DC motor having a much higher operating voltage.

Abstract: A control circuit for connection to a split capacitor motor automatically switches to reverse operation when the motor is caused to stop or slow unacceptably by a heavy load. During operation, a voltage is maintained across a relay winding which is sufficient to hold the relay contacts in the normally open position. A slowing or stopping of the motor causes a reduction the voltage across the relay winding, which permits the relay contacts to switch to a configuration that reverses the phase of the current through the main and auxiliary windings of the motor, thereby reversing the motor.

Abstract: An overload control circuit and method of operation for protecting a three-phase motor from damage due to overload includes monitors reading the load on each phase of the motor and circuitry for combining the three separate phase signals into a single combined load signal which triggers the overload circuit. The gain on the combined load signal and the overload trip delay time may be calibrated and monitored by an external meter to provide for accurate and inexpensive calibration to accommodate specific operating characteristics of the motor being monitored. The circuit provides visual readouts of the mode of operation, including: (1) operating mode; (2) overload onset; (3) shut down initiated; and (4) delay to restart.

Abstract: The switching of upper and lower switching elements is controlled by respective upper and lower arm driving circuits. Those switching elements are connected in series across a primary d.c. power source and their successive switching generates a drive voltage which is applied to a load. A secondary d.c. power source is connected to the lower arm driving circuit while the upper arm driving circuit is connected to a capacitor connected to the high potential side of the primary d.c. power source. The capacitor is charged from the secondary d.c. power source through a charging circuit. This driving arrangement is particularly applicable to multi-phase driving circuits.

Abstract: A single phase, capacitor start electric motor is shown in which energization of the auxiliary winding is controlled by a triac. The triac is protected from excessive voltages caused by the vector sum of capacitor, line and induced voltages which can occur at turn-off of the triac. The triac is protected in several embodiments by a gated semiconductor switch serially connected to a current limiting or discharge resistor, both being coupled across the triac. The semiconductor switch has a voltage breakdown device connected in its gate circuit. When voltage across the triac exceeds a selected level the gated semiconductor is turned on thereby drawing sufficient current momentarily to limit the voltage across the triac to a safe level and allowing the capacitor to discharge its voltage through the auxiliary winding circuit. In another embodiment a stack of high voltage bilateral triggering devices is placed across the triac.

Abstract: A controller for a dual speed induction motor selectively applies operating power to the low speed motor terminal or the high speed motor terminal according to the open circuit/closed circuit condition of a low temperature thermostat and a high temperature thermostat. For low speed operation, operating power is conditionally applied to the low speed motor terminal through the low temperature thermostat and through the normally closed circuit of a single pole, double throw switch. For high speed operation, operating power is conditionally applied to the high speed motor terminal through the high temperature thermostat and the normally open circuit of the single pole, double throw switch. The operating position of the single pole, double throw switch is determined by a solenoid which is connected in series circuit relation with the high temperature thermostat.

Abstract: A motor controller is adaptable to a wide range of motor currents by using an integrator circuit having an additional feedback arrangement for affecting the effective time constant of the integrator under specified conditions. The operational amplifier has an amplifier having a first input, a second input, and an output, an input resistor connected between an input of the operational amplifier and the first input of the amplifier, and a feedback impedance connected between the output of the amplifier and the first input of the amplifier. A voltage at the input of the operational amplifier is compared with a voltage at the first input of the amplifier. An auxiliary current path for the feedback impedance is provided when the voltage at the input of the operational amplifier has a predetermined relationship to the voltage at the input of the amplifier.

Abstract: Refrigeration system control systems and methods for protecting a refrigerant motor/compressor, for example in an air conditioner, against conditions of excessive loading. The systems and methods of the invention recognize and distinguish between conditions of high operating load and insufficient condenser airflow, and take appropriate action for each. High operating load conditions are responded to by providing a motor/compressor cool-down interval, followed by a restart, so that an air conditioner remains operating at its maximum capacity, consistent with the field conditions. Insufficient condenser airflow conditions are responded to by eventually terminating operation of the motor/compressor until, for example, a service technician is called. Operation is based on a recognition that excessive loading conditions are manifested much sooner when the cause is insufficient condenser airflow than when the cause is a high operating load.

Abstract: Calibrated methods and systems for protecting refrigerant motor/compressors against overload and loss of refrigerant conditions, independent of compressor and system size, while avoiding the need for a plurality of sensors. The disclosed methods and systems are generic in the sense that they may be employed in a variety of different air conditioner or heat pump models of different sizes and capacities, without being specifically tailored for a particular model, although a factory calibration adjustment is required. The disclosed methods and systems sense loading on the compressor motor, and make control decisions based thereon. A permanent compressor motor reference loading is established when the refrigeration system has a known correct refrigerant charge and the motor/compressor has a known load. This is typically accomplished in the factory after a predetermined stabilization interval has elapsed following initial start up of the motor/compressor.

Abstract: A motor protector having a thermostat metal element thermally coupled to an electrical motor in a refrigerator compressor motor system has a heater responsive to motor current thermally coupled to the thermostat metal element and has an improved component arrangement to provide locked rotor and ultimate trip protection for the motor without requiring calibration of the operating temperature for the protector after assembly or after incorporation in the motor system.

Abstract: A motor controller with means responsive to a motor condition for preventing termination of power to the motor in response to fault conditions when these fault conditions occur during start-up of the motor.

Abstract: An electrical circuit for connecting an electric motor to an electrical source of supply comprising a double pole single throw switch having four quick-connect terminals thereon. Two of said terminals are connected to the electrical source of supply and the other two of said terminals connected directly to the windings of the electric motor. A centrifugal switch is provided, mounted internally of the housing of the electric motor on an insulated electric circuit board. The supply leads bypass the electric circuit board on which the centrifugal switch is mounted, thus minimizing the number of terminals and electric circuit connections and increasing the reliability and safety of the circuit.

Abstract: A control system for electrically powering from an external alternating-current power source a direct-current underwater hand-operated tool or light activated by a switch. The control system includes a relay for connecting and disconnecting the external AC power source to and from the system, a transformer connected to the relay for transforming the AC power to a desired lower voltage level, a converter connected to the transformer for converting the transformed AC to DC power, cables for supplying the DC power to the tool, and a control circuit for sensing the voltage level of the transformed AC power and in response to the sensed voltage level increasing beyond a predetermined safe level, causing the relay to disconnect the external AC power source from the system. The control includes a Zener diode for sensing the voltage level of the transformer AC power, and a transistor and an SCR for controlling the operation of the relay.

Abstract: A stall detection method for electric induction motors and apparatus utilized the stator current and voltage phase difference as proportional to percentage synchronous motor speed, and detects a stall condition from this speed as a parameter of motor movement. The invention includes differentiating the phase difference to obtain motor acceleration as a parameter potentially indicative on its own, or in conjunction with phase difference, of a motor stall condition.

Abstract: A microprocessor controlled motor starter is utilized in which an operator can preprogram within limits the number of starts which a motor can be subjected to in a programmed period of time to thus prevent destruction of the motor by accumulated overheating. Significantly more heat is generated during a start of a motor than during the run mode. The foregoing is accomplished by utilizing memory locations in which accumulated times from a first start are sequentially stored in order. If the time found in the latest memory location is larger than the predetermined maximum allowable time then the start is allowed to take place. If it is less than that time then the start is prevented from taking place and a readout alerts the operator as to how much time must expire before the next allowable start may take place.

Abstract: A protection device and circuit for a fluid pump or the like including a motor control relay MS for actuating relay contacts MS-1, MS-2, MS-3 that control the communication of power to a drive motor 10a, and a manual reset motor protection device 24 that deenergizes the control relay in response to sensed malfunctions. The motor protection device comprises a manual reset motor protector 40 having switch contacts 42 connected in series with the motor control relay and a tripping coil 44 which, when energized, opens the switch contacts. A current shunt path 46 including serially connected pump assembly mounted sensors 48, 50, normally shunts current around the tripping coil and is interrupted in the event of a sensed malfunction, causing the energization of the tripping coil which opens the switch contacts and deenergizes the drive motor. The switch contacts must be manually reclosed to reactivate the pump assembly.

Abstract: Overload protection for a multispeed motor is provided in the form of a plurality of line break motor protectors positioned in good heat transfer relation with the motor windings and having heating elements in circuit with the motor windings to be responsive to excessive winding current and/or excessive winding temperature to disable the windings. Certain of the line break motor protectors are operational in more than one motor speed configuration. The line break motor protectors may be of the self-resetting temperature sensing variety and circuitry is included to insure that the motor does not restart until all protectors are reset subsequent to an overload condition.

Abstract: A motor control system includes a motor system having a pole-amplitude-modulated (PAM) motor, a motor breaker, and a speed switch coupled between the motor breaker and the PAM motor. The PAM motor is coupled to a fan in an exhaust duct having a controlled damper for controlling air flow therethrough. A control system step logic sequencer includes means responsive to permissive signals for providing in sequence control signals to the motor breaker and speed switch in response to confirmation signals received from the motor breaker, the speed switch and the PAM motor.

Abstract: The invention relates to a speed control system which includes an inverter circuit for converting a direct current into a polyphase alternating current in the form of a rectangular wave by the switching action of transistors, and an inverter drive circuit adapted to apply control signals to the inverter circuit to bring its output frequency to a desired value, an AC motor being rotated by the alternating current supplied by the inverter circuit. The system features current detection means for detecting the current that flows thrugh the input side of the inverter circuit, and a circuit adapted to terminate the operation of the inverter circuit when the value detected by the current means approaches a value large enough to damage the inverter circuit transistors as at such time that a large momentary current is subjected thereto.

Abstract: A circuit for protecting single phase induction motors of the type having a start winding connected in series with a start/run capacitor. The circuit contains a resistance bridge wherein the motor start winding forms one leg thereof. A d.c. signal is applied to the input terminals of the bridge. A filter is connected to the output terminals of the bridge so that a relatively ripple free d.c. output signal from the bridge can be applied to the positive input terminal of a d.c. comparator, the negative terminal of which is connected to d.c. reference ground. A reference resistor in a leg of the bridge adjacent the start winding is selected so that the bridge is unbalanced to present a positive d.c. signal to a terminal of the comparator so long as the resistance value of the start winding is less than the value of the reference resistor.

Abstract: A solid state electronic circuit for protecting a single phase induction motor against excessive loading by comparing motor start winding voltage with motor source voltage is disclosed, wherein the circuit automatically removes the motor from its driving source upon the occurrence of such excessive loading. An additional feature includes comparing start winding voltage with source voltage to remove the motor from its driving source upon the occurrence of excessive start winding voltage and corresponding excessive high motor speed. A motor starting circuit to permit the start winding voltage to rise to its normal running level and a time delay restarting circuit to permit the motor to automatically restart after elapse of a selected lock out period following removal of the motor from the source due to insufficient or excessive loading is also provided.

Abstract: A prime mover has a stationary assembly with a generally annular grouping of winding end turns extending therefrom, and a structural member of the prime mover is spaced from the winding end turn grouping. An overload protector device is disposed in abutting engagement with a part of the winding end turn grouping, and means is associated with both the stationary assembly and the overload protector device and arranged in biasing engagement with the structural member for positioning the overload protector device in the abutting engagement thereof with the part of the winding end turn grouping.A method of assembling a device with the prime mover is also disclosed.

Abstract: A solid state bilateral switching device such as a Quadrac is serially connected with the start winding of a split phase motor and is triggered through a switch which is actuated when the motor approaches normal operating speed.