Automatic focusing arrangement for enlarging apparatus

Claim 1

AN AUTOMATIC FOCUSING ARRANGEMENT FOR AN ENLARGING APPARATUS INCLUDING A CARRIAGE SUPPORT AND AN EASEL COMPRISING A MAIN CARRIER ASSEMBLY MOVABLY MOUNTED UPON SAID CARRIAGE SUPPORT FOR MOVEMENT TOWARD AND AWAY FROM SAID EASEL, AN OBJECTIVE LENS MOUNTED UPON SAID ASSEMBLY, A NEGATIVE CARRIER, MOVABLE MEANS MOUNTING SAID NEGATIVE CARRIER UPON SAID ASSEMBLY FOR MOVEMENT TOWARD AND AWAY FROM SAID OBJECTIVE LENS ALONG THE OPTICAL AXIS OF SAID ENLARGING APPARATUS, CONTROL MEANS MOUNTED UPON SAID ASSEMBLY AND REACTING AGAINST SAID NEGATIVE CARRIER FOR ADJUSTING THE DISTANCE BETWEEN SAID NEGATIVE CARRIER AND SAID OBJECTIVE LENS TO FOCUS SAID APPARATUS, A REFERENCE COUPLING CONNECTING SAID CONTROL MEANS TO SAID CARRIAGE SUPPORT FOR ADJUSTING SAID CONTROL MEANS IN ACCORDANCE WITH THE POSITION OF SAID ASSEMBLY RELATIVE TO SAID EASEL WHEREBY SAID FOCUSING DISTANCE OF SAID NEGATIVE CARRIER FROM SAID OBJECTIVE LENS IS AUTOMATICALLY ADJUSTED, AND SAID CONTROL MEANS COMPRISING DISK, CAM AND FOLLOWER MEANS FOR ADJUSTING SAID NEGATIVE CARRIER TO THE PROPER DISTANCE FROM SAID OBJECTIVE LENS TO PROVIDE A SHARP FOCUS FOR SAID APPARATUS FOR ALL POSITIONS OF SAID OBJECTIVE LENS RELATIVE TO SAID EASEL.