Electric switch control unit, more particularly for electric motor driven actuators

A motor driven actuator having a control unit comprising:

• a motor;
• means coupling said motor drive shaft to an input drive shaft of said actuator;
• a pair of switches each connected in an electric circuit, a first of said switches controlling the operation of the motor in one direction of movement of the actuator, and a second of said switches controlling the operation of the actuator in the other direction of movement, an actuating member for each switch for operating the corresponding switch at any point during the stroke of the actuator in accordance with the output force or the output movement of the actuator, a latch member associated with said switch actuating members, said latch member being drivably connected with the input drive shaft of said control unit for movement relative to one of said switch actuating members depending on the direction of movement of the actuator, a pair of pins for normally preventing movement in a first direction, said pins being mounted one on each of said switch actuating members and being each positioned in a first location during normal operation of said actuator prior to actuation of said switches;
• said pair of pins being movable with its switch actuating member upon movement of the actuating member to its switch operating position from said first location to a second location in which said latch member is movable into a position in which the latch member locks the actuating member in its switch operated position, said latch member operating to prevent the release of said switch actuating member whereby a corresponding switch is reset until the actuator input drive shaft moves in the reverse direction of said first direction.