Abstract: A drive system for a group of brushless A.C. motors (15) which have mutually different working characteristics, for example mutually different voltages or frequencies, and which are arranged to be supplied with electric energy from a static converter (4). The system is characterized in that all motors (15) are arranged to be connected electrically, one at a time, to one and the same converter, and in that an identifying means (10, 13) which is individual to each motor is arranged to be connected to a control input (8, 9) on the converter in order to regulate the converter so that it generates electric energy with the necessary supply parameters to the motor. The invention also covers a hand-tool to be used in the system.

Abstract: In a DC motor driving device, upon detection of a change in the content of an input digital signal, supply of signals to switch elements from the output terminals of the decoder is suspended for a predetermined period of time following the detection of the change, and, during this predetermined period of time, the decoder's logical conversion operation is accomplished. With this arrangement, the difficulty of two series-connected switch elements being simultaneously applied with a voltage and turned on simultaneously is eliminated.

Abstract: A window operating system includes a motor control circuit for controlling the operation of direct current permanent magnet motors mounted on window operators associated with each window. Each of the motors on each of the windows is connected to the control circuit only by a pair of wires which both power the motor and provide information to the control circuit as to the status of motor operation. The status of motor operation is determined by monitoring the back electromagnetic force expressed by the motors. To help differentiate back electromagnetic force from supply voltage supplied to the motors, the motors are supplied with full rectified alternating current power, rather than simple direct current, so that the presence or absence of zero voltage between half waves of the voltage expressed across the motors can be monitored to determine the absence or presence of back electromotive force during those time periods.

Abstract: A numerical control system in which a numerical control device is adapted to control a machine tool equipped with a plurality of tables, as one example, on which workpieces may be secured to be machined by a tool mounted on a head. A table which is not being controlled automatically by the numerical control device can be operated independently of the automatic operation network of the numerical control device and placed in a manual operation mode or manual data input mode in which the table can be moved manually even while the numerical control device controls the other table or tables automatically.

Abstract: In the inching of a grinding mill or similar apparatus which is driven by a pair of synchronous motors through fluid actuated clutches, the motors must be angularly alined one with the other in order that the load be shared equally between the motors. The apparatus of the invention connects the field supply to both motor fields and then it connects a zero frequency supply (i.e. a DC supply) to the stator windings of both motors and ramps up or increases the amplitude of the supply. This brings the rotors into alinement without undue oscillation. When the amplitude of the low frequency supply reaches a predetermined level, the clutches are closed or locked and the motors are connected to the load with the rotors in angular coincidence or alinement.

Abstract: A process for changing a running direction of an electromagnetically guided driverless vehicle is provided which process is applicable to the vehicles of both a single conduction wire guided type and a two conduction, wires guided type. The vehicle has right and left drive wheels and independent drive motors for the respective wheels. The drive motor is controlled by a motor speed control drive to which steering signals from a route sensors are supplied. The route sensor also delivers an on-route signal to a steering control device which produces a speed setting signal, a steering signal on-off command, and a forward/reverse command for the right/left drive wheels to supply them to the motor speed control device. The process for changing the running direction of the vehicle is characterized in the method of driving the right and left wheels independently with each other forward and reverse according to the turning direction.

Abstract: A control system, more particularly for the electric motors driving a vehicle for the disabled, comprising a control member for delivering a required speed signal which varies linearly with the position of the control member, a feed back control circuit for each motor, a power supply for the motor and the control circuits, the linear speed signal is compared with a signal selected, on the basis of the instantaneous speed of the motor, to form a number of signal which are stored in a memory, and for forming a control signal which does not vary linearly with the speed signal. The control signal is fed to the motor control circuit to keep the rotation of the motor constant.

Abstract: A control arrangement for manually controlling speed and direction of devices such as electric motors typically where these drive the two driving wheels of a wheel chair, the control being achieved by having the radiant energy falling on several detectors, these being responsive to radiant energy falling on them from an emitter and this being controlled by the position of a reflective surface which is coupled to a control arm, the outputs from each detector being compared electronically both to determine whether the motor or motors should drive in a forward or rearward direction and their speed.

Abstract: An electric propulsion and braking system which includes a plurality of high-speed, dc commutatorless motors each coupled to a wheel of an automotive vehicle through an associated fixed-ratio mechanical transmission. Each motor includes a field winding, an armature winding, and a commutation circuit for the armature winding. During propulsion, each commutation circuit is enabled and, during braking, each commutation circuit is disabled. Control of the amount of propulsion and braking is afforded by varying the dc source voltage across each commutation circuit and by varying the field current in each field winding. The dc source voltage across each commutation circuit is varied by connecting the commutation circuits and a plurality of main electrical energy sources in selected series, series/parallel, and parallel combinations.

Abstract: A system for controlling the rotation of a motor comprises a detector for detecting the rotation of the motor, frequency discriminator for frequency discriminating the output of the detector, a loop filter comprising resistors and a capacitor which lowers the high-frequency components of the output signal of the frequency discriminator, a switching circuit which is connected to the output side of the loop filter, the switching circuit grounding the output side of the loop filter and discharging the capacitor of the loop filter in a state before starting of the high-speed rotation of the motor, and non-grounding the loop filter in a state in which the motor is undergoing high-speed rotation, and a motor driving circuit which drives the motor in accordance with the output signal of the loop filter through the switching circuit.

Abstract: Device for feeding a consumable wire electrode. Two feeding units are mounted in tandem. Each of the feeding units is provided with a pair of rolls and coupled to a direct current motor driving one of the rolls in the pair. The two motors are connected in series.

Abstract: Control circuitry for producing signals to control motors which propel a ile platform for a standing paraplegic. Logic circuits connect a 3-axis joy stick controller to four permanent magnet DC motors mounted on the platform such that the platform follows in the direction of the displacement of the joy stick. The joy stick outputs are taken as inputs to several differential amplifiers. Each of a plurality of velocity servo amplifiers receives one input signal from the differential amplifier output and another from a tachometer feedback signal derived from each motor. Comparators receive the velocity servo amplifier outputs as well as a triangular wave input. Each comparator comprises a pulse width modulator which generates pulse outputs whose duty cycle is a function of the voltage inputs to each comparator. The comparator outputs then control motor rotation such that the platform moves in the direction of displacement of the joy stick.

Abstract: A switching control circuit for an electrically adjustable patient chair that utilizes a relay control circuit comprised of a plurality of switching control relays connected in a binary switching arrangement which in the preferred embodiment herein, permits the use of only three control relays to control six motor adjustment functions.

Abstract: The control system includes a plurality of light responsive devices and a mask structure having a part which is movable with respect to the devices to control the transmission of light thereto. The movable part of the mask structure may be a ball-like member, which is universally supported in a spherical receptacle which supports the light responsive devices. Four light responsive devices may be used, with the mask structure having a portion with a variable width slot associated with each device, so that as the ball-like member is pivoted universally to control the light transmitted through the slots to the devices, electrical signals are produced which represent the movement. The light responsive devices have an electrical characteristic which changes with the light applied thereto to produce electrical signals, and are connected in a control circuit so that signals therefrom control apparatus, such as drive units for controlling the movement of a device.