Abstract: An arm driving apparatus for an articulated robot, which is equipped with a worm wheel adapted to move the arm, a worm gear for driving the worm wheel, and a drive motor for driving the worm gear.

Abstract: A robot operation control system for point-to-point movement is disclosed in which each motor is provided with a microcomputer and a predetermined acceleration/deceleration control is effected for each microcomputer, so that specified given points may be passed smoothly in a given sequence.

Abstract: In a control apparatus controlling point-to-point movement of arms of a robot, stepping motors are used to drive the shafts of the robot arms respectively, and motor drivers drive the stepping motors according to a 1-2-phase excitation mode in a low speed range but according to a 2-phase excitation mode in an intermediate and a high speed range.

Abstract: A relay control circuit is disclosed in which a timer circuit is actuated by a reference clock pulse in synchronism with an AC voltage supplied by a commercial power supply. An output signal of the timer circuit causes current to flow in the coil of the relay thereby to close the contact of a relay. The invention further comprises a polarity-reversing device for reversing the polarity in accordance with the variations in the output signal of the timer circuit. The reference clock pulse is applied to the timer circuit through the polarity-reversing device.

Abstract: An automatic control apparatus for protecting the compressor motor used with the refrigeration system of an air conditioning unit. The control apparatus has a timer for prohibiting the restart of the compressor motor until the lapse of a predetermined time after temporary stoppage of the compressor motor, and a holding circuit for holding a power source voltage for a predetermined period of time while the operation of the air conditioning unit is stopped. Even if the power supply is turned off, therefore, the source voltage supplied by the holding circuit enables the timer circuit to continue its operation for a predetermined length of time.