Control unit for a medical device

In a medical device operated by a control computer having a computer keyboard, the improvement of a control unit for said medical device comprising:

• a work chair adapted to receive a medical device operator;
• an actuation element disposed on said work chair at foot level, and adapted to be actuated with a side of a foot of a medical device operator on said work chair;
• means, upon actuation of said actuation element, for emitting an electrical control signal to said control computer for controlling said medical device, and
• said actuation element comprising a closed pressure bellows connected to a hose conduit, and wherein said means for emitting said control signal comprising a pressure transducer in communication with said hose conduit which emits an electrical signal upon compression of said bellows, and electronic evaluation means, supplied with said electrical signal, for generating said control signal upon compression of said bellows.