Clamping device for clamping printing plates of printing machines

Claim 1

A CLAMPING DEVICE FOR RELEASABLY CLAMPING A PRINTING PLATE IN A CLAMPING SLOT OF A TENSIONING RAIL OF A PRINTING MACHINE, SAID CLAMPING DEVICE COMPRISING A CLAMPING MEMBER FITTED IN SAID CLAMPING SLOT MOVABLE TRANSVERSE OF THE LENGTH THEREOF BETWEEN A PLATE CLAMPING POSITION AND A PLATE RELEASING POSITION, AND POWEROPERATED MEANS COACTING WITH SAID CLAMPING MEMBER AND OPERABLE FOR SELECTIVELY MOVING THE SAME INTO EITHER OF ONE OF SAID POSITIONS, SAID POWER-OPERATED MEANS COMPRISING A SERVO SYSTEM INCLUDING A CLOSED CYLINDER, A PLUNGER COACTING WITH THE CLAMPING MEMBER SLIDABLE IN SAID CYLINDER, AND CONDUIT MEANS FOR SUPPLYING A PRESSURE MEDIUM TO THE CYLINDER AT A SELECTED SIDE OF THE PLUNGER THEREIN TO DISPLACE THE SAME IN THE RESPECTIVE DIRECTION, AND TRANSMISSION MEANS COUPLING SAID PLUNGER WITH SAID CLAMPING MEMBER, SAID TRANSMISSION MEANS INCLUDING IDLING MEANS PROVIDING FOR DISPLACEMENT OF THE PLUNGER THROUGH A PREDETERMINED DISTANCE PRIOR TO TRANSMITTING THE DISPLACEMENT OF THE PLUNGER TO THE CLAMPING MEMBER.