Abstract: An apparatus for detecting an object adjacent an elevator door includes a housing (47) mounted at an upper edge of a car door opening (38) and in which are mounted a plurality of short range detector pairs (50) and a plurality of long range detector pairs (53). Each short range detector pair includes a transmitter (14,25,40) for generating a relatively short range infrared beam (18,27,42) toward a path of travel (16) of an elevator door (17) across the door opening and a short range receiver (15,26,41) for detecting a reflection (31) of the beam from a facing surface (17b) of the door and generating a short range beam detection signal.

Abstract: Disclosed are methods and apparatus for quickly measuring a primary resistance value of an AC motor without using high precision detectors and detecting malfunctions such as breaking of wire in the AC motor or in a power converting mechanism, open phase, and three-phase unbalance. A voltage drop attributable to the primary resistance of the AC motor can be estimated by using an estimated resistance value R.sub.1.sup.#, which is estimated in turn by an integral or proportional-plus-integral operation on the deviation between a detected magnetizing current value I.sub.M and a reference magnetizing current value I.sub.M *, in place of an actual primary resistance value R.sub.1. The time for the estimated resistance value R.sub.1.sup.# to reach the true primary resistance value is reduced with a varying reference magnetizing current value I.sub.M **. Variations of the estimated primary resistance values R.sub.1.sup.# s between the phases are corrected with a mean estimated primary resistance value R.sub.1M.sup.

Abstract: Safe operation of a transfer device on a press is provided by the present invention. In the transfer device in which the drive of servo motors in the drive units 1, is caused to be synchronized with the operation of the transfer press itself by positionally controlling motions of beams through servo controllers a torque value of a specific transfer pattern actually measured under normal operation is established to be a reference torque value of the transfer pattern; a torque allowance is calculated by defining the upper and lower limit torque values by adding or subtracting a preliminarily set deviation value to or from the reference torque value in a CPU of a control unit, and the torque allowance is stored in the control unit. The actual torque value is compared with the torque allowance to acknowledge whether or not the actual torque value is within the stored torque allowance in later forming operation using the same transfer pattern.

Abstract: A servo system includes a communication cable which is disposed between a servo control circuit and a servo amplifier. A feedback cable and a power cable are each connected between the servo amplifier and a servo motor. The communication cable includes a command signal line from the servo control circuit to the servo amplifier and a feedback signal line. The command signal line includes three PWM signal lines instead of six PWM signal lines through the use of inverters in the servo amplifier, ground lines, an enable signal line, and other various signal lines. The feedback signal line transmits a position feedback signal, which is sent from the servo motor via the servo amplifier, to the servo control circuit. Thus, a number of signal lines between the servo control circuit and the servo amplifier become unnecessary and are used as feedback signal lines for transmitting position feedback signals from the servo motor.

Abstract: An object of the present invention is to obtain a reluctance-type motor which generates small vibration, rotates at a high speed, generates a large output torque, and provides a flattened torque characteristics. A rotor is provided with n (n is a positive integer not less than 2) salient poles having the same width and equally spaced at regular angles, and a first fixed armature is provided with magnetic poles confronting the outer peripheral surface of the rotor. The magnetic poles are wound by three- or two-phase armature coils. A second fixed armature and its associated rotor with salient poles are provided to add an output torque eliminating ripple torque of the output torque generated by the first fixed armature.

Abstract: A starting circuit for use with single phase induction motors such as capacitor run and capacitor start, capacitor run motors is shown having a triggerable semiconductor (Q1, Q2 and Q3) serially connected to the auxiliary winding (AW) across the power supply (L1, L2). A resistor (RA) is serially connected at (J1) to the main winding (MW) to form a voltage divider to aid in providing triggering current to the triggerable semiconductor. A thermistor (PTC) is connected between the gate and the voltage divider junction (J1). The triggerabIe semiconductor is shown as a triac (Q1) in certain embodiments and as back to back SCRs (Q2 and Q3) in other embodiments. In high current motors the voltage divider resistor (RA) is shown thermally coupled to the thermistor (PTC).

Abstract: A torque detecting apparatus for an AC motor is provided which includes a current detecting circuit, an angular position detecting circuit, a torque detecting circuit, and a ripple reducing circuit. The current detecting circuit detects a phase current flowing through each winding of the motor. The torque detecting means determines a torque value indicative of the amount of torque of the AC motor based on the phase currents detected by the current detecting circuit according to an angular position detected by the angular position detecting circuit. The ripple reducing circuit reduces ripple contained in the torque value according to the angular position of the motor for determining an accurate amount of torque of the motor.

Abstract: A closure system for a motor vehicle includes a closure, a closure frame, an electric motor, a control switch, an electric power source, first and second displacement sensors, temperature sensor, voltage sensor of the power source and a microprocessor. The first and second displacement sensors each operably generate a signal indicative of the one of closure movement and output shaft rotation. The microprocessor is electrically connected to the control switch, the electric motor, the first and second displacement sensors, the temperature sensor and the voltage sensor of the power source. The microprocessor includes electrically connecting the motor with the power source responsive to a condition of the control switch. The microprocessor also has means for converting temperature sensed to an electrical signal indicative of the temperature.

Abstract: An anti-theft system for a motor vehicle includes a portable transponder carrying code information. A stationary transceiver has an oscillator and an oscillating circuit being excited to oscillate by the oscillator at an oscillation being modulated by the transponder in synchronism with the code information. A demodulator demodulates the modulated oscillation of the oscillating circuit. According to one embodiment, the code information is obtained from the demodulated oscillation by sampling the oscillation at least at one predetermined sampling time. An arithmetic unit compares the code information with command code information and transmits an enable signal to a security unit if a match occurs. The modulated oscillation being shifted by a predetermined phase angle is sampled once again if initially no code information is recognized from the demodulator.

Abstract: A circuit and method for controlling commutation of an electric motor includes first and second n-bit counters. The counters alternately serve as model reference and model following counters during alternate zero-cross intervals of a detected back-emf signal which is generated during rotation of the electric motor. The model following counter counts clock cycles occurring since a detected zero cross and continues counting until an optimal commutation switching point is detected, which is ideally located halfway through a commutation interval. A masking circuit is provided to mask spurious zero cross detections during a desired masking interval. A soft switching circuit determines commutation starting and ending points which are symmetrically located with respect to a center point of a commutation interval. Overflow protection circuits protect the counters from overflow during long commutation intervals and the like, and the internal clock is modulated to prevent overflow during certain operating conditions.

Abstract: A brushless motor driving circuit is provided for obtaining a reliable starting and stable rotation driving irrespective of the load condition of the motor. The brushless motor driving circuit has a terminal voltage detector located at each phase of the armature windings of the motor, a terminal voltage compensator for adding or subtracting a compensation value to/from the terminal voltage of the armature windings detected at respective phases during actual driving periods, and a comparator for comparing respective terminal voltages to obtain a rotor location signal after compensation has been performed. The compensation value is determined by a resistor of the armature winding and a winding current. The armature windings are driven by the rotor location signal detected at the comparator.

Abstract: A method bridges gaps in a power supply for electrical, converter-fed rail vehicles having front and rear ends with front and rear current collectors, as seen in a travel direction, for making contact with the power supply. The method includes switching a traction converter from a traction mode to a regenerative braking mode, that is to say a generator operation or from a braking mode to the regenerative braking mode. The switching takes place over a period during which the rail vehicle travels a distance. If possible, the distance is only slightly shorter than a distance between the front and rear current collectors. This occurs as soon as the front current collector is not in contact with the power supply.

Abstract: An apparatus for electrically setting the overload compensating magnetic reluctance in a single phase induction watthour meter includes a moveable magnetic shunt positioned adjacent the poles of a current core of a current stator circuit. An electrical parameter of the current stator circuit is sensed and changes in this parameter are used to set the air gap between the magnetic shunt and the current core poles. In one embodiment, a programmable controller controls a motor to move the shunt in response to variation of the sensed electrical parameter from a predetermined value. In one method, the sensed electrical parameter is the voltage induced in a first current coil when a second current coil is energized. In other methods, the sensed electrical parameter is the flux induced in the magnetic shunt or the self inductance of a current coil.

Abstract: Apparatus for compensating for positioning, pointing and/or orientation errors caused by deflections of structural members and components of a high performance machine or device and/or for reducing vibration inputs to such machine or device and/or for micro-positioning such machine or device so as to improve the operational performance of such machine or device. The apparatus utilizes one or more active-type actuators, such as piezoelectric ceramic type actuators, which are arranged in a predetermined manner relative to the machine or device. A servo control device operating in accordance with a predetermined algorithm may be utilized for controlling the actuators or, alternatively, the apparatus may operate in an open loop manner.

Abstract: Starting of single phase permanent magnet direct current motors in the desired direction of rotation is accomplished by providing a look up table stored in memory giving the correct sign or polarity of current for the angular position of the permanent magnet rotor of the motor. This stored look up table is developed by initially injecting current pulses of opposite polarity at different angular positions of the rotor, determining the difference between the rise times, and mapping the sign and the magnitude of the differences versus angular position. Thereafter, to start the motor in the correct direction, it is only necessary to inject current pulses of opposite polarity to know the angular position of the rotor and the polarity of the current required to start the motor in the correct direction. After the motor has been started, it is commutated by blanking the drive current at the zero crossings of the back emf.

Abstract: An electrically operated power steering apparatus basically has a steering torque sensor, a steering rotational speed sensor, and preferably a vehicle sensor. A controller outputs a motor control signal based on a steering torque, a steering rotational speed, and a vehicle speed which are detected by the steering torque sensor, the steering rotational speed sensor, and the vehicle sensor, respectively. The motor control signal is applied to control a motor driver to output a motor drive signal which energizes an electric motor to produce an assistive steering force or a braking force. The electrically operated power steering apparatus is effective to improve steering and returning characteristics of a steering system, and give the steering system a stable steering capability.

Abstract: In current servo amplification/control apparatus and method for a reversible DC motor applicable to a vehicular four-wheel steering system, a motor current detection circuit and a motor current feedback circuit are eliminated and a motor counter-electromotive force is estimated using a dynamic characteristic of the motor, a positioning currenu, and an angular displacement information of the motor, and the motor power supply voltage directly measured is corrected using the estimated counter- electromotive force. Thus, a positioning response of the motor is derived which is approximately coincident with a design target even when the motor is rotated at a high speed.

Abstract: A system for driving a blower of a heating, ventilating, and/or air conditioning (HVAC) system. The blower discharges heated or cooled air to a space for conditioning the air in the space by changing its temperature. A motor drives the blower at a speed or torque defined by a motor control signal thereby to control air flow rate of the HVAC system. The system includes a temperature sensor generating a temperature signal representative of the temperature of the air discharged to the space by the blower. In response to the temperature signal, a control circuit generates the motor control signal to cause the motor to operate at a minimum speed or torque until the temperature of the discharged air as represented by the temperature signal reaches a reference temperature.

Abstract: A system which drives a component of a heating, ventilating, and/or air conditioning (HVAC) system in response to a system control signal such as a temperature signal provided by a thermostat. The system includes a motor having a stationary assembly and a rotatable assembly. The rotatable assembly is in magnetic coupling relation to the stationary assembly and is in driving relation to the component. The motor drives the component in response to a control signal generated by a microprocessor. The microprocessor is responsive to parameters representative of the system and to the system control signal. The parameters are stored in a memory and are defined in response to a parameter select signal. The control signal provided by the microprocessor controls the speed and torque of the motor. The system further includes an instruction memory for storing instructions controlling the operation of the microprocessor.

Abstract: A system for controlling the energy output of a combustion-powered, fastener-driving tool in which a fan is arranged to produce turbulence in a combustion chamber when the fan is driven, in which a direct current motor is arranged to drive the fan when a driving voltage is applied across the motor, and in which a battery provides a battery voltage not less than the driving voltage. A voltage divider includes a settable resistance, either a potentiometer or two parallel, fixed resistances that can be alternatively selected, and is used to provide a setpoint voltage. A comparator, an inverter, and a transistor switch are arranged to sample a voltage proportional to the rotational speed of the fan, to compare the sampled voltage to the setpoint voltage, to apply the driving voltage across the motor if the sampled voltage is less than the setpoint voltage, and to remove the driving voltage from across the motor if the sampled voltage is not less than the setpoint voltage.