Abstract: A control unit for automatically controlling the angular position of a reversible, motorized device, such as an antenna rotor, in response to a signal from an external sensor, such as a potentiometer coupled to the rotating shaft of a windvane. The unit includes integrated circuits and other electronic components for monitoring the windvane signal and for activating the rotor, as necessary, to maintain its alignment with the sensed wind direction. The unit also comprises means for providing: a no-response zone of adjustable width about the momentary, average wind direction; an adjustable, time delayed response to changes in wind direction; an automatic reversal of rotation if the rotor approaches the .+-.180.degree. position while searching for the wind direction; an automatic disabling of the rotor for windspeeds less than a selectable, threshold value.

Abstract: An electronic control system for controlling the operation of electromotive apparatus utilizes a capacitive sensor for sensing human touch and producing a command signal whose magnitude corresponds to the contact area of the contact. The sensor command signal is applied to an oscillator which produces a series of output width pulses having a frequency corresponding with the magnitude of the sensor command signal. A discriminator detects the trailing edge of the oscillator pulses and produces a series of fixed width pulses and an integrator produces a D.C. voltage signal corresponding to the discriminator output, which voltage signal corresponds to the area in proximity to and thereby stimulated by the human body. A comparator is employed to produce a pulse-width modulated rectangular pulse output whose duty cycle corresponds to the integrator D.C. voltage by comparing the integrator D.C. voltage with a reference triangular waveform.

Abstract: A phase-triggered, gate-controlled AC semiconductor switch, in series with an induction motor and its AC supply, optimizes power flow to the motor under changing mechanical load conditions by varying the amount of supply voltage applied to the motor over each half-cycle of the AC supply. Such power flow optimization is effected by utilization of a control voltage generated by the freewheeling induction motor during nonconduction periods of the switch. The triggering point of the switch relative to the preceding zero crossing point of the supply voltage, that is, the switch firing angle or delay angle, is varied by the control voltage augmenting to a varying degree the charging rate of a capacitor that triggers the semiconductor switch into conduction.

Abstract: An electronic control means utilized in an electrically actuated shift apparatus for a multispeed axle including an electric power source and an electric motor coupled to actuate means for shifting the axle. The power source is connected to the electric motor through a shift speed control switch and a plurality of steering diodes. When the switch is actuated to select an axle speed, power is applied through one of the steering diodes to one side of the armature of the motor. Power is also applied through another of the diodes as a shift signal to a timing circuit. A first means is responsive to the shift signal for generating a first control signal for a first predetermined time. At the termination of the first control signal, the timing circuit generates a second control signal to connect the other side of the motor armature to ground thereby actuating the motor.

Abstract: A commutator motor can be set to different speeds by changing the external circuit connections between the single phase AC supply line and the stator field winding. The field winding is distributed in slots over at least part of the circumference of the stator bore and the field winding connection is switched, when going from a lower to a higher speed, in such a way that the axis of the stator field is rotated in the direction of rotation of the motor. For improved performance, the number of excitation turns may also be changed, simultaneously with the rotation of the field axis. The motor is particularly useful for automatic washing machine drives having a universal motor.

Abstract: Electric motor control apparatus includes a variable-frequency oscillator 10, a counter 11 clocked by the oscillator, and signal generating means 12 arranged to generate two sinusoidal voltages in quadrature with one another. The two voltages are applied through separate amplifiers 22, 23 to separate stator windings 24, 26, of the motor, the stator windings being 90.degree. apart. Control means includes a bistable circuit 28 producing a signal lagging 45.degree. behind one sinusoidal voltage, and a phase sensitive detector 29 arranged to vary the frequency of the oscillator 10 to maintain a constant phase difference.

Abstract: An apparatus for controlling a DC motor driven screw feed which moves the table of a machine tool into prescribed positions including a plurality of limit switches which detect the position of the table, a rate change control circuit which receives signals from the limit switches and changes the rate of revolution of the DC motor when the table has reached prescribed rate change positions and a current limiting circuit which supplies the DC motor with a prescribed constant current and keeps the output torque of the DC motor at a prescribed level when the table has reached a prescribed dwell position.

Abstract: An electronic timepiece of the type having a frequency dividing circuit, and a drive circuit for driving a motor having a rotor, a stator and a driving coil, is provided with a magnetic field detection device comprised of a low impedance closed loop including a low resistance element and the driving coil and a high impedance closed loop including a high resistance element and the driving coil. The driving coil develops an induced voltage when placed in an external alternating magnetic field and also functions to drive the rotor. The strength of the alternating magnetic field is measured by the voltage level developed across the high resistance element and the measuring sensitivity is improved by alternately switching between the low impedance closed loop and the high impedance closed loop.

Abstract: A method of suppressing resonances in electro-mechanical servo systems is disclosed. The servo systems are of the type where first signals indicative of actual position of the servo system are differentiated and second signals indicative of the acceleration of the system are integrated. The differentiated signals are applied to the integrator in order to provide accurate initialization thereof. In modes of operation where the acceleration of the system is substantially zero, the differentiators are not used, thus decoupling the mechanical system from the electronic control system and eliminating resonance from the servo loop. The duty cycle of the differentiators is varied in differing modes of operation of the servo system so as to provide maximum bandwidth and speed to the system coupled with minimum errors in positioning. The system is described in connection with the servoing of magnetic read/write heads radially with respect to rotating magnetic disk data storage media.

Abstract: An electronic timepiece includes a stepping motor having a stator, a drive coil and a rotor which is driven in one of at least two different states. The state of the driving motor is changed in response to a change in the load of the motor or in response to the locating of the motor in an external magnetic field.

Abstract: An electronic timepiece has a stepping motor comprised of a stator, rotor and driving coil. A wave shaping circuit produces normal driving pulses and correction driving pulses having a longer pulse width than the normal driving pulses. A rotor rotation detection device detects rotation and non-rotation of the rotor after normal driving pulses are applied to the driving coil and in response to detection of a non-rotation condition, a correction driving pulse is applied to the driving coil. A magnetic field detection device detects the presence and absence of an external alternating magnetic field and in response to detection of a magnetic field, a driving pulse of longer pulse width than the correction driving pulses is applied to the driving coil to effect rotor rotation.

Abstract: Step motor control in which a coded emitter disk is formed with a plurality of sensible secondary marks between each pair of primary motor step marks for use as different optional delay times for the generation of a motor advance pulse after a step mark is sensed. A circuit is disclosed to select predetermined ones of the secondary marks which will generate motor advance pulses in a closed loop system. This arrangement of secondary marks permits the elimination of circuits of fixed delays for feedback signals which are inappropriate when the motor load or temperature varies.

Abstract: An alternating current machine drive system, comprised of an alternating current machine and an inverter configured of a plurality of pairs of transistors with the transistors of each pair coupled in series-aiding fashion and each of the pairs of serially coupled transistors connected across a direct current source, is controlled in accordance with inverter current. The transistors of each inverter transistor pair are alternately rendered conductive to supply alternating current at the inverter output in accordance with a current error signal, proportional to the difference in magnitude between actual inverter phase current and a sinusoidal reference signal, with the conduction state of the transistors of each pair reversing each time the current error signal exceeds an upper and lower hysteresis limit, which limits vary in accordance with actual inverter phase current.

Abstract: An integrator is illustrated which provides normal action integration operation as long as the input signals remain a given polarity. However, when the input signal changes in polarity, the integrating capacitor is substantially instantly discharged and then the integrator integrates, from the discharged capacitor condition, in the changed polarity direction until the input signal polarity again changes.

Abstract: A stepper motor damping control system. Damping is performed by switching the power supply connection(s) of energized motor phase windings alternatively ON and OFF at a predetermined relatively high fixed rate. Said switching is performed using a clock signal information for switching one way and an information denoting equality between a voltage substantially proportional to the current flowing through said motor phase windings with a predetermined sawtooth sloped reference signal synchronized with said clock signal for switching the other way.

Abstract: A numerical control system is provided for a table having a relatively stationary member, a relatively movable member and a position transducer, such as an inductosyn, operatively positioned between them. The numerical control system comprises a high frequency clock which generates a pair of sinusoidal waves to the inductosyn at a lower frequency and the phase of the output signal from the inductosyn is representative of the position of the movable and stationary members. A direction and speed control circuit generates an output signal the frequency and polarity of which is indicative of the desired speed and direction of movement of the movable member, respectively, and this output signal is combined with the high frequency signal from the clock by a signal combiner.

Abstract: In a control apparatus of a flying shear wherein a clutch is actuated to transmit the rotation of a drive motor to a cutting blade to rotate the same for achieving cutting and then the clutch is disengaged and the cutting blade is stopped by means of a brake, there are provided a speed signal generator for generating a signal corresponding to the speed of the cutting blade, a rest point establishing device for establishing a rest point for the cutting blade, an operation circuit receiving the output of the speed signal generator and performing an operation, and an instruction circuit responsive to the output of the operation circuit and the output of the rest point establishing device to produce at least one of an instruction for declutching and an instruction for braking.

Abstract: An alignment apparatus for mask and wafer each having alignment marks provided in a narrow strip like area between circuit patterns is disclosed, which mask and wafer are used in manufacturing semiconductor circuit elements. In the apparatus, the mask and wafer are scanned to obtain scan signals by means of which the amount of relative deviation between the alignment marks on mask and wafer is detected. By means of the detected signal, an alignment is effected between the mask and wafer in the apparatus. For this type of alignment apparatus, there is a problem that since the alignment marks are provided in the narrow strip like area, no coincidence between the scanning position and the strip area is attainable with pre-alignment accuracy. Improvement in the alignment apparatus according to the invention lies in that a reading of alignment marks is initiated after the coincidence is photoelectrically detected.

Abstract: Disclosed is a control circuit of a positioning device for moving a member to be controlled to a predetermined position by using a d-c motor, in which there are used arithmetic circuit means for detecting a difference signal, to be converted to a driving signal of the motor, between the position detecting signal of the member and the reference signal of the predetermined position, and correcting circuit means coupled to the arithmetic circuit means for causing the difference signal to be small, whereby the motor is free from the hunting phenomenon.

Abstract: An actuator for use in the nature of a servomotor, having means for providing a signal indicative of the position of a mechanical linkage member. A feedback signal source voltage is alternately connected to a feedback signal lead by switch means which are carried by the mechanical linkage member of the actuator. Variable resistance means can be inserted between the voltage source and the feedback signal lead to provide a plurality of feedback signal voltages, each of which indicates a different position of the actuator linkage member.