Rotary printing press register clutch

Claim 1

A PRINTING PRESS COMPRISING A PAIR OF PRINTING UNITS; EACH OF SAID PRINTING UNITS INCLUDING AN IMPRESSION CYLINDER HAVING GRIPPER MEANS THEREON FOR ADVANCING SHEETLIKE MATERIAL THROUGH ITS PRINTING UNIT; A CHAIN TRANSFER MECHANISM HAVING GRIPPER MEANS FOR RECEIVING THE MATERIAL FROM THE GRIPPER MEANS ON THE IMPRESSION CYLINDER OF ONE UNIT AND FOR TRANSFERRING THE MATERIAL TO THE GRIPPER MEANS ON THE IMPRESSION CYLINDER OF THE OTHER PRINTING UNIT; COMMON DRIVE MEANS FOR SAID PRINTING UNITS INCLUDING A CLUTCH MEANS FOR DISCONNECTING THE PRINTING UNITS FROM EACH OTHER SO THAT EACH OF SAID PRINTING UNITS MAY BE DRIVEN INDEPENDENTLY OF THE OTHER; A DRIVE FOR SAID CHAIN TRANSFER MECHANISM FROM AT LEAST ONE OF SAID PRINTING UNITS AND INCLUDING A PRINTING UNIT DRIVE GEAR DRIVEN FROM SAID COMMON DRIVE MEANS, A CHAIN TRANSFER DRIVE GEAR DRIVEN FROM SAID PRINTING UNIT DRIVE GEAR, A DRIVE SHAFT FOR DRIVING SAID CHAIN TRANSFER MECHANISM, A DRIVE MEMBER DRIVINGLY CONNECTED WITH SAID DRIVE SHAFT TO EFFECT ROTATION THEREOF UPON ROTATION OF SAID DRIVE MEMBER, SAID DRIVE MEMBER AND SAID CHAIN TRANSFER DRIVE GEAR EACH HAVING A DRIVING SLOT THEREIN WHICH SLOTS HAVE AN ALIGNED POSITION, A DRIVING KEY MEMBER MOVABLE INTO SAID SLOTS AND PROVIDING A DRIVE CONNECTION BETWEEN SAID DRIVE MEMBER AND SAID CHAIN TRANSFER DRIVE GEAR AND MOVABLE FROM SAID SLOTS TO BREAK THE DRIVE CONNECTION THEREBETWEEN; AND MEANS SEPARATE FROM SAID DRIVE MEMBER FOR MOVING SAID KEY INTO AND FROM SAID SLOTS WHEREBY ALL THE ROTATIONAL FORCE FOR DRIVING SAID CHAIN TRANSFER DRIVE SHAFT IS TRANSMITTED THROUGH SAID DRIVING KEY MEMBER AND SAID DRIVE MEMBER.