Operating mechanism for medium and high voltage switchgear, in which a rotatable main shaft is coupled to a switch, and a rocker plate is rotatable with the main shaft, the main shaft being arranged to open and close said switch by tilting the rocker plate. The rocker plate constitutes a plurality of force transmission levers and comprises a plurality of zones distributed around the main shaft. A rotary actuator has force transmitting means for driving the rocker plate in a direction corresponding to closing of the switch, and an opening spring for driving the rocker plate in a direction corresponding to opening of the switch. Closed switch locking means are coupled to the rocker plate (4) and are disposed substantially in a common plane of the rocker plate.