Mechanism for holding and tensioning a printing plate on a printing cylinder

Claim 1

A MECHANISM FOR HOLDING AND TENSIONING A FLEXIBLE PRINTING PLATE WRAPPED AROUND A PRINTING CYLINDER HAVING A PERIPHERAL CHANNEL EXTENDING BETWEEN THE CYLINDER ENDS, WITH A FIRST TRANSVERSE EDGE OF SAID PRINTING PLATE HAVING A BAR ATTACHED THEREALONG AND EXTENDING INTO SAID CHANNEL, SAID MECHANISM COMPRISING: AN ELONGATED BASE IN SAID CHANNEL; MEANS ADJUSTABLY MOUNTING SAID BASE IN SAID CHANNEL FOR LONGITUDINAL DISPOSITION IN A DIRECTION PARALLEL TO SAID FIRST TRANSVERSE EDGE OF SAID PRINTING PLATE; A SUPPORT ELEMENT FIXED TO SAID BASE; A MEMBER EXTENDING UPWARDLY FROM SAID SUPPORT MEMBER; JAW MEANS AT THE UPPER END OF SAID MEMBER FOR ENGAGEING SAID BAR AT THE FIRST TRANSVERSE EDGE OF THE PRINTING PLATE AND FOR TENSIONING THE PRINTING PLATE; MEANS MOUNTING SAID MEMBER ON SAID SUPPORT ELEMENT FOR PIVOTAL MOVEMENT OF THE MEMBER WITH SAID JAW MEANS BETWEEN A FIRST ENGAGING POSITION AND A SECOND RETRACTED DISENGAGED POSITION; A SPRING ROD PIVOTALLY ATTACHED AT ONE END THEREOF TO SAID MEMBER AND EXRENDING SLIDABLY THROUGH SAID SUPPORT ELEMENT; A SPRING PLATE AT THE OTHER END OF SAID SPRING ROD AND LONGITUDINALLY ADJUSTABLE THEREON; SPRING MEANS, ENCIRCULING SAID SPRING ROD, HAVING ONE END THEREOF ABUTTING SAID SUPPORT ELEMENT AND THE OTHER END THEREOF ABUTTING SAID SPRING PLATE, WHEREBY SAID ENGAGING MEANS IS NORMALLY URGED TO ITS FIRST POSITION; AND MEANS, ON SAID SUPPORT MEMBER, ACTUABLE TO RETRACT THE ENGAGING MEANS TO ITS SECOND POSITION; AND MEANS ON SAID BASE FOR ACTUATING SAID RETRACTING MEANS.