Abstract: In a telephone network, different telephones are connected to a telephone line in a parallel manner. When two or more of the telephones are in use and conduct electricity, known as an “off-hook” condition, they are oftentimes provided with varying amounts of loop current from the telephone line to drive their telephone circuitry. To balance the respective loop current supplies to the off-hook telephones, at least one inventive balancing network is used and connected to one of the off-hook telephones which has the least operating resistance, with respect to all other off-hook telephones.

Abstract: A rotary actuator includes a shaft rotatably mounted on a body, and a servovalve arranged to operate a vane motor for selectively rotating the shaft relative to the body. A portion of the shaft extends beyond the body. Supply and return passages are provided to the body and shaft so that fluid power supplied to the body is supplied to the servovalve and is also available at the end of the shaft beyond the body. Two or more such rotary actuators may be connected by intermediate brackets to provide a wrist actuator capable of movement about axes.

Abstract: An electronic starting circuit for a single-phase electric motor is disclosed in which the motor has a first, and possibly a second, main winding and has an auxiliary winding used for starting. The voltage across the auxiliary winding increases as the motor speed accelerates and is used as a sensing signal. This signal is applied through an amplifier to a peak detector which determines the peak DC output and compares it with a reference voltage. When the reference voltage is the larger, then an auxiliary switch connected in series with the motor auxiliary winding is closed for starting of the motor. When the peak DC output voltage from the peak detector exceeds the reference voltage, the auxiliary switch is opened. Instant reversing of the motor is possible by discharging a capacitor in the peak detector at the time of reversal so as to re-energize the auxiliary winding. The circuit also operates on a two-speed motor.

Abstract: A high response servovalve has an improved valve spool slidably mounted within the bore at a sleeve or body. The bearing surfaces on the spool are formed of a relatively soft material. The balance of the surfaces of the spool and the sleeve or body are relatively hard. The soft bearing material tends to absorb contaminants between the bearing lands and the sleeve, is self-healing, and is not prone to weld to the facing sleeve or body surface.

Abstract: Mechanical feedback through an articulated mechanism is provided between the swashplate of a variable displacement hydraulic device and the output stage of an electrohydraulic servovalve for controlling such swashplate.

Abstract: Mechanical feedback through an articulated mechanism is provided between the swashplate of a variable displacement hydraulic device and the output stage of an electrohydraulic servovalve for controlling such swashplate.