Portable film viewer

Claim 1

IN COMBINATION, A PORTABLE FILM VIEWER AND A FILM STRIP CARTRIDGE, ROTATABLE FILM TRANSPORT MEANS IN THE CARTRIDGE, MECHANICALLY OPERABLE DRIVING MEANS IN THE VIEWER FOR DRIVING THE FILM TRANSPORT MEANS COMPRISING: A SELECTOR KNOB ROTATABLY MOUNTED UPON A WALL OF SAID VIEWER; A SPINDLE ASSEMBLY SPACED FROM SAID SELECTOR KNOB, SAID SPINDLE ASSEMBLY INCLUDING A VERTICALLY ORIENTED DRIVE SHAFT FOR DRIVING SAID TRANSPORT MEANS, SAID DRIVE SHAFT BEING SPRING LOADED TO AN UPPER ENGAGING POSITION AT WHICH IT ENGAGES SAID FILM TRANSPORT MEANS AND BEING MOVABLE AGAINST SAID SPRING ACTION TO A DISENGAGED POSITION, SAID SPINDLE ASSEMBLY ALSO INCLUDING A RELATIVELY HORIZONTALLY DISPOSED GEAR AFFIXED TO SAID DRIVE SHAFT, SAID DRIVE SHAFT BEING VERTICALLY SLIDABLE WITHIN SAID GEAR; A DRIVING WHEEL AFFIXED TO SAID SELECTOR KNOB AND RELATIVELY VERTICALLY DISPOSED; A DRIVE CHAIN INTERCONNECTED BETWEEN SAID GEAR AND SAID DRIVING WHEEL; AND AN ARCUATE CHAIN SUPPORT MEMBER POSITIONED BETWEEN SAID DRIVING WHEEL AND SAID GEAR, WHEREBY SAID CHAIN IS DIRECTED FROM A SUBSTANTIALLY HORIZONTAL POSITION AT SAID GEAR TO A SUBSTANTIALLY VERTICAL POSITION AT SAID DRIVING WHEEL.