Abstract: The invention relates to a method for operating a closing device, wherein a closing element (2), with the aid of a drive motor (4) controlled by a control unit (7), can be displaced in a closing direction up against a stop edge, wherein the control unit (7) can be shifted into a normal-operation mode, in which position-related information is sensed as the current position of the closing element (2), and into a sleeping mode, in which no sensing of position-related information takes place, the method having the following steps: —interrogating whether a wake-up condition, in which the control unit (7) goes from the sleep mode into the normal-operation mode, is present; —if the presence of the wake-up condition is established, and if the closing element (2), prior to assuming the sleep mode, last moved in the closing direction, the position-related information is subjected (S25) to a predetermined correction value in order to correct the position-related information, in respect of an actual position of the closi

Abstract: An electric machine including a housing, a stator mounted within the housing, a rotor rotatably mounted within the housing relative to the stator, and a vibration sensor arranged within the housing. The vibration sensor includes a sensing member configured and disposed to detect vibrations of the electric machine.

Abstract: An electric drive machine includes an electric drive system including an internal combustion engine and an electrical power generator coupled to the internal combustion engine. An electronic controller is in control communication with the electric drive system and is configured to determine an estimated temperature of a rotor of the electrical power generator at least in part by determining a rotor temperature rise estimation, compare the estimated rotor temperature to a rotor temperature threshold, and initiate an excessive temperature action if the estimated rotor temperature is greater than or equal to the rotor temperature threshold.

Abstract: A motor control device includes a dq-axis current control unit for generating a dq-axis voltage reference based on a dq-axis current reference and a dq-axis current signal, an initial magnetic pole position estimation unit for estimating a magnetic pole position of the motor upon power-on to generate a magnetic pole position signal, and a magnetic pole position estimation precision confirming unit for supplying a current in a d-axis direction after generation of the magnetic pole position signal with the initial magnetic pole position estimation unit, and checking an error of the magnetic pole position signal based on an angle of movement of the motor.

Abstract: A drive unit includes a rotating electrical machine; a rotation sensor that detects a rotational position of a rotor of the rotating electrical machine, and a storage medium. In an inspecting step of measuring a counter electromotive force by mechanically driving the rotating electrical machine after the rotating electrical machine and the rotation sensor are assembled together, positional error information of the rotation sensor obtained based on information of the counter electromotive force and output information from the rotation sensor is stored in the storage medium. The storage medium is integrally provided to the drive unit in such a state that the storage medium is readable upon assembling a control device that controls the rotating electrical machine.

Abstract: A collector ring for use with a center pivot irrigation system which permits the mounting of a communication device above the span structure. The collector ring also includes a monitoring device which senses the angle or rotation of the span structure with respect to the fixed center pivot structure.

Abstract: In determining a starting point of a motor of an electric actuator during its initialization procedure, when a rotation angle sensor detects pulse signals in a certain initialization pattern, power supply to the motor is stopped by the control of a motor drive circuit. This electrical control of motor rotation enables the initialization procedure of the actuator to be carried out without using mechanical restriction means for locking purposes, and the influence of variations in the deflection amount of any stoppers is eliminated. The precision in determining the starting point in the initialization procedure is thus improved.

Abstract: Apparatus for monitoring fan speeds within a computing system includes a tachometer turning with the fan, providing a tachometer signal including a number of pulses during each revolution of the fan. This tachometer signal is provided as an input to a signal generator in the form of a flip-flop, which generates a square-wave signal having transitions between high and low levels corresponding to tachometer signal pulses. The square-wave signals are provided as inputs to separate input ports of a microprocessor. These input ports are sequentially sampled at a rate providing at least two samples per period of the fastest square-wave signal, so that transitions of each square wave signal during a predetermined time interval can be detected and counted. For each input port, the number of counted transitions is compared to a stored acceptable value to establish whether the fan is operating in an acceptable speed range.

Abstract: A fan speed pulse filter is used for a PWM fan. The filter comprises a comparator, a latch circuit and a synchronizer. The fan unit, including a tachometer pulse output, is controlled by a PWM signal for determining the fan speed. By comparing the PWM signal with a reference voltage, the comparator generates a reset signal. The latch circuit, coupled to the comparator and the fan unit, receives the reset signal and the tachometer pulse and outputs a filtered tachometer pulse containing no phantom pulses. Furthermore, a synchronizer generates an output signal without interruption when the PWM signal is switched off.

Abstract: High resolution and accuracy of the measured values for detection of the position, speed and/or acceleration of a drive is ensured. The tolerances are determined and considered in signal evaluation on a partitioned basis. Measurement errors caused by inaccuracies of the signal generator due to manufacturing difficulties are greatly reduced or eliminated such that use of signal generators without particularly high quality specifications is possible. Thus, use of less exact components in generation and detection is possible.

Abstract: A mini-blind actuator has a motor and a housing that holds the motor and a dc battery. The rotor of the motor is coupled to the baton of the mini-blind for rotating the baton and thereby opening or closing the slats of the mini-blind. Alternatively, the rotor is coupled to the tilt rod of the blind to rotate the tilt rod and thereby open or close the slats of the mini-blind. A control signal generator generates a control signal for completing the electrical circuit between the battery and the motor. The control signal can be generated in response to a predetermined amount of daylight or in response to a user-generated remote command signal. The actuator can be used to rotate the slats of horizontal or vertical blinds, or the sections of a pleated shade. Or, the actuator can be used to rotate the hollow rotatable tube of a roll-up shade.

Abstract: A tachometer for monitoring the rotation of an output shaft (e.g. of a motor, where the motor is enclosed within a standard NEMA housing), includes an enclosure (e.g. adapted to be secured to an end plate of the motor housing), the enclosure having a radial center and a longitudinal axis which, when the enclosure is secured to the housing, are aligned with a longitudinal axis of the output shaft. The enclosure has at least one mounting surface in a peripheral wall portion thereof, the mounting surface having an aperture formed therein which opens in a radial direction. A sensor module including a pair of axially aligned magneto-resistive sensors is mountable on the mounting surface of the enclosure such that the module protrudes through the aperture with the sensors facing radially inwardly.

Abstract: A motor control system accurately and reliably controls the speed of a motor so that the motor operates in accordance with a predetermined motor speed profile, and therefore does not exceed a predetermined safe speed, decelerates at a controlled rate, maintains a safe minimum speed, and does not turn in reverse. If the motor operates out of these limits, a malfunction is indicated and the control system halts operation of the motor. The motor speed is determined using an electronic tachometer that analyzes the current in at least two phases of the motor to provide extremely precise and reliable velocity information for the motor.

Abstract: A motor control system accurately and reliably controls the speed of a motor so that the motor operates in accordance with a predetermined motor speed profile, and therefore does not exceed a predetermined safe speed, decelerates at a controlled rate, maintains a safe minimum speed, and does not turn in reverse. If the motor operates out of these limits, a malfunction is indicated and the control system halts operation of the motor. The motor speed is determined using an electronic tachometer that analyzes the current in at least two phases of the motor to provide extremely precise and reliable velocity information for the motor.

Abstract: The present invention provides a system for controlling the rotational speed of a rotary member such as a video tape recorder drum or the like. The system detects a zero crossing interval in the output of a frequency generator, adding it to the subsequent zero crossing interval in the delayed output signal and using the result to control the motor or the like.

Abstract: A circuit arrangement for generating a useful direct voltage signal associated with the frequency of an alternating current signal serves, in particular, to regulate the synchronism of an electric motor. It includes a comparator circuit (7) which converts the two opposite polarity half-waves of the alternating current signal of a tacho coil (2) into pulses whose edges trigger a measuring and control circuit (18) which generates direct voltages corresponding to the half-period durations of the alternating current signal measured from the respective zero passages.

Abstract: A circuit arrangement for generating a useful direct voltage signal associated with the frequency of an alternating current signal serves, in particular, to regulate the synchronism of an electric motor. It includes a comparator circuit (7) which converts the two opposite polarity halfwaves of the alternating current signal of a tacho coil (2) into pulses whose edges trigger a measuring and control circuit (18) which generates direct voltages corresponding to the half-period durations of the alternating current signal measured from the respective zero passages.

Abstract: A frequency-voltage converting system has a first sampler for sampling the input signal at a predetermined time interval, a second sampler for sampling the input signal after elapse of a predetermined time period from said predetermined sampling time, and comparator for comparing the sampled values obtained respectively from said first and second samplers and providing the difference of said sampled values as a value proportional to the frequency of said input signal.

Abstract: An improvement in door activating control apparatus including a short delay between the time the door is stopped during its closing direction of travel and starts moving in the opening direction when any one of any switch or button for opening the door is activated, prevents the stress incurred when the door is required to instantly reverse its direction of travel while closing, demonstrates a distinct advantage especially when controlling large heavy doors, or for door openings that require a high volume of traffic and in emergency situations, includes a means to by-pass the delayed reversing when the door is in the closed position. Features a novel means of using a single pole double throw switch which will serve to defeat a safety edge device and by-pass the delayed reversing, embodied in a single enclosure along with the door closing limit switch, all actuated by a single mechanical actuating device at the door closed position, demonstrates distinct advantages in door operator design.

Abstract: A pulse width modulated DC motor control system is designed to operate a DC motor at constant velocity. Feedback pulses generated at a rate proportional to the rotational velocity of the motor are converted to control pulses having a fixed on-time period which is independent of changes in the velocity of the motor. The control pulses are used to modulate a constant current source whose output is integrated to generate a sawtooth voltage signal whose average DC value is used as the basis of or pulse width modulating a DC voltage applied to the motor drive circuits of a DC motor.

Abstract: A reversible motor operates a vertically movable door through transmission means including a friction clutch. Control means receiving the output of a tachometer generator driven by the driven member of the friction clutch are arranged to switch off the motor automatically in response to a predetermined deviation downwards of the rate of rotation caused by an obstruction in the path of the door. The system may include means for automatically re-starting the motor in the opposite direction subsequent to a switching-off caused by an obstruction to the travel downwards of the door.

Abstract: A variable speed tape transport apparatus for a tape cassette wherein the tape is driven at a selected one of plural predetermined speeds. The cassette includes speed indications thereon, each indication representing a respective normal tape speed. These indications are sensed by a sensor which, in turn, controls a control circuit for the tape drive motor such that the tape is selectively driven at a normal relatively lower speed or at a normal relatively higher speed. In addition, a selector mechanism, such as a fast-forward or rewind mechanism, is provided to enable the tape to be driven at a fast speed, this fast speed being at least equal to the relatively higher normal speed.In one embodiment, a tape cassette to be driven at the relatively lower normal speed can be selectively driven at a first higher speed, equal to the relatively higher normal speed, and at a second even higher speed.

Abstract: Circuit apparatus for providing a signal indicative of speed and direction of rotation of a d-c machine is provided which utilizes an a-c tachometer output as the speed signal from the bi-directional d-c machine. The circuit apparatus includes means responsive to the armature terminal voltage and armature current to provide a signal proportional to the counter electromotive force generated in the armature. Polarity circuit means responsive to nulls in the armature current and the signal proportional to the counter electromotive force generates a signal which is a function of the polarity of the counter electromotive force. An absolute value circuit means is provided for receiving the output of an a-c tachometer driven by the d-c machine.