Abstract: In a control circuit, which has a current switching-over circuit including at least four switching transistors for controlling a current flowing through an electromagnetic device, the control circuit has driving circuits each of which drives the switching transistors in such a way that a short circuit does not occur during the switching-over operation thereof.

Abstract: An automatic control system for such a prime mover as a vehicle engine is adapted to automatically stop the prime mover when such a driven device as a vehicle is arrested, to automatically drive the prime mover in response to operation of a starting mechanism for effecting start of the driven device, and to maintain the prime mover in its operative condition when the driven device is moving. The control system is arranged to be inoperative in an expected occurrence of an error in operation of a setting switch for the system and to indicate the operative condition of the system under normal control of the setting switch.

Abstract: An automatic velocity calibrator for a head positioning servo system in a magnetic disk drive performs a velocity calibration in a single pass over the magnetic disks by measuring actuator velocity and adjusting the gain of the velocity transducer in a series of successive approximations. Velocity is determined by turning a timer on in response to a track crossing and turning the timer off after at least two successive track crossings have been detected. A plurality of velocity measurements are stored and averaged. The average velocity is compared to a constant velocity command and an 8-bit latch is incremented or decremented in response to this comparison. A digital to analog converter produces a reference for an automatic gain control amplifier in the servo system which in turn adjusts the velocity transducer gain.

Abstract: By choosing the winding and drive circuit configuration of a conventional two phase step motor so that during any one step time, a drive current pulse in one winding is not magnetically coupled to the other winding, then the back EMF induced in this other winding by the permanent magnet of the motor can be used to generate a feedback emitter pulse. The zero crossings of the induced EMF coincides with the detent positions in a conventional two phase step motor. Only one winding of the two phase step motor is driven during any step time. In order to use this same winding as an emitter signal source during the next step time, the drive current in this winding is reduced to zero before the zero crossing of the EMF waveform which is induced in this winding by the permanent magnet of the motor. The drive current is quickly reduced by using a supply voltage substantially higher than the rated motor voltage.

Abstract: Use of a programmable source of stepping pulses to control the speed of linear movement of a material from a supply spool to a takeup spool wherein feedback signals provide an indication of the angular velocity of the supply spool and a function table provides information on the rate of stepping pulses to be applied to the takeup spool.

Abstract: An automatic control system for machine tools having rotary tools is disclosed in which the tool drive motor load current, which is proportional to the mechanical load on said drive motor, is maintained at a selectable desired level by controlling the duration and phase of the power supplied to an alternating current feed motor which controls the distance between the rotary tool and the workpiece. A sensed load signal which is greater than the preselected level will cause the feed motor to move the tool away from the workpiece, while a load signal less than that desired will cause the feed motor to move the tool toward the workpiece.

Abstract: A logic circuit (34) is provided for preventing the application of energizing voltage to a positioning motor in the case of a circuit failure in the drivers stage of a control system. An equality gate provides a signal to each AND gate corresponding to a failure detection criterion whenever signals of the same level are present at the respective transistors controlling operation of the motor into opposite directions. At one AND gate a signal is provided if either of the transistors is conducting, indicating a failure if there is no control signal. At the other AND gate a signal is provided if either terminal of the motor is connected to energizing potential, likewise indicating a failure if no control signal at a transistor input is present. If either AND gate responds the equivalent of a control signal is applied to a pair of diodes to both of the transistor inputs, thereby blocking the motor.

Abstract: A microprocessor numerical control for a milling machine including means for programming part features by the machine operator at the machine location. The control apparatus includes a CRT display which provides an inquiry system, and a keyboard for entry of data by the machine operator. The control system further includes a tape cassette deck operable to read or write data or program material into or out of the processor memory. The control system regulates motion in the X, Y and Z directions for the milling machine and also includes an external feed rate adjustment for either the XY plane or the Z axis direction which may be utilized by the machine operator to affect the programmed feed rates. There is further provided automatic tool length calibration and cutter diameter compensation for milling operations.

Abstract: Method and system of controlling an inverter are disclosed. A reference rotary magnetic flux as a desired magnetic flux of an AC motor is so determined as to make a uniform rotary motion, an actual magnetic flux of the AC motor is detected, voltage vectors are selected such that a deviation between this reference rotary magnetic flux and the magnetic flux of the AC motor may be a value held within a tolerance, and switching elements of the inverter are on-off controlled so that the voltage vectors thus selected can be obtained.

Abstract: Positioning of a movable body can be achieved at a high resolution by making use of two position signals generated by a position detector, whose magnitudes are sinusoidal functions having different phases of the position of the movable body. On the basis of the two sinusoidal position signals, two bi-level digital position signals having different phase from each other are derived, and digital control for movement of the movable body is effected by making use of these two bi-level digital position signals until the movable body is brought into the proximity of a desired position. Thereafter, control is switched from the digital control to analog control for movement of the movable body, in which a position signal whose manitude is a sinusoidal function of the position of the movable body and has a zero-cross point at the desired position is used as a reference position signal.

Abstract: An X-ray table having an elevator mounted on a base for vertical movement, an intermediate support mounted on the elevator for moving longitudinally, and a carriage with a patient cradle on it for moving longitudinally on the support. A pair of gas springs mounted at the forward end of the table provides a constant upward force to compensate for weight of the elevator and the cantilevered load which is exerted as the patient cradle is extended in the longitudinal direction. There are individual servomotors for driving the support and the cradle. The intermediate support drive includes a drive bar and switch assemblies for sensing any force of more than 25 lbs., for example, exerted on the patient or patient cradle and for disengaging the servodrives in response thereto. The cradle drive incorporates a zero-backlash longitudinal friction drive which includes a harmonic drive unit to achieve accurate positioning of the patient.

Abstract: A waste kinetic energy reclaiming system for an engine-driven vehicle includes a generator, and a variable torque-ratio coupling connecting the generator and the vehicle engine. The system also includes a clutch which selectably disconnects the coupling from the engine in response to whether or not braking of the vehicle is required so that the connection between the coupling and the engine is established only when braking is required.

Abstract: A method and apparatus for controlling the angular position of a motor by controlling the revolution of the motor in response to a given positioning command value commanding a predetermined angular position of the motor shaft so as to stop the motor shaft at the predetermined angular position, wherein the acceleration of the motor being accelerated in the initial acceleration stage of the motor position control operation is calculated, and on the basis of the calculated acceleration and a commanded maximum velocity, the remainder angular distance between the deceleration starting angular position and the desired angular position of the motor and the deceleration command value in the deceleration stage are calculated so as to control the deceleration of the motor on the basis of the calculated values.

Abstract: A numerical control unit which includes a main bus connected to (a main processor) operates, according to an execution program stored in a main memory, on data from the memory or a tape reader, and applies the results of the operation to axis-control circuits in order to perform predetermined numerical control. The main memory and buffer circuits (4a to 4c in FIG. 1) are connected to the main bus. This minimizes the electrical load on the main processor. Peripheral buses are provided for each of the buffer circuits, and peripheral hardware and the axis-control circuits of individual package units are each connected to the peripheral buses.

Abstract: A method and apparatus by which the output value of a resolver position detection system is compensated for systematic phase shift errors produced by signal conditioning circuitry through which the signal passes.

Abstract: A multi-lead component manipulator for the assembly of circuit boards has optical and tactile feedback systems and includes at least two and preferably three symmetric assemblies radially disposed about a component gripper assembly. Each symmetric assembly has a movable lead guide means for engaging a component lead and aligning the same for circuit board insertion. The guide means are adapted for independent arcuate and radial motion reflective of the optical feedback system and the gripper assembly is capable of axial movement for the acquisition and insertion of components. The tactile feedback system controls component insertion. The manipulator in an alternative embodiment has fixed guide means disposed above the movable guide means. The fixed guide means orient the component leads for acquisition by the movable guide means.

Abstract: An electrically operated dual motor drive system having first and second reversible traction motors (14, 16) driven by a power source (18). Motor control circuitry (10, 12) for controlling the direction of current flow through the motors (14, 16) is designed to be actuated by only two coils (36, 42). Preferably, control circuits (10, 12) employ an arrangement of normally open (32a, 32b, 38a, 38b) and normally closed (34a, 34b, 40a, 40b) contacts such that the two motors (14, 16) operate in reverse directions in the event of a complete system malfunction. A line contactor (20) is advantageously utilized to simultaneously serve as a main power disconnect for a variety of motors within the system.

Abstract: A digital control device includes a first controller which generates a control reference signal of a first controlled variable of a controlled system, a first frequency converter which converts said control reference signal into pulses of a frequency proportional to a magnitude thereof, a second frequency converter which converts a measured value of a second controlled variable of said controlled system into pulses of a frequency proportional to a magnitude thereof, and a second controller which obtains a difference between the output pulses of said first frequency converter and the output pulses of said second frequency converter and which controls said second controlled variable by using said difference as a control reference value.

Abstract: A numerical control apparatus for a machine tool (4) comprises a transmitting circuit (43) for transmitting each block of machining information to an abnormal operation monitoring apparatus (6), which comprises a receiving circuit (61) for receiving each of said blocks of machining information and a decoding circuit (63) for decoding the content of said received blocks of machining information, thereby, as the machining proceeds by each one block, data indicating the content of said block and a signal indicating the termination of execution of the machining operation defined in said block are supplied from said numerical control apparatus (4) to said abnormal operation monitoring apparatus (6) and said content of each block of machining information is decoded in said abnormal operation monitoring apparatus (6).

Abstract: A step motor provided with a plurality of coils and driven in a one-two phase excitation mode is provided with a current setting device by which the current flowing in the coils is changed when switching from one to two phase excitation, to linearize the time dependence of the rotation angle of the motor.