Linear control mechanism

Claim 1

IN COMBINATION WITH A MECHANICAL TIMER HAVING A TRAIN OF GEARS ROTATABLY DISPOSED THEREIN, A LINEAR CONTROL MECHANISM COMPRISING A SHAFT JOURNALED WITHIN THE TIMER, SAID SHAFT HAVING A GEAR SECURED THEREON IN MESH WITH A GEAR IN SAID TRAIN OF GEARS FOR TIMER ROTATION OF SAID SHAFT, A SPRING ACTUATED MEMBERS MOUNTED FOR MOVEMENT BETWEEN TWO POSITIONS IN ONE OF WHICH IT IS TO BE RESTRAINED, MEANS CARRIED BY SAID SHAFT FOR RESTRAINING SAID SPRING ACTUATED MEMBER IN SAID ONE OF ITS TWO POSITIONS AND RELEASING SAID MEMBER IN ONE POSITION OF RELATIVE ROTATION OF SAID SHAFT, A CAM MEMBER HAVING CONTOURED SURFACE SECURED TO THE SHAFT, AND AN ELONGATED SPIRAL COIL SPRING POSITIONED WITHIN THE TIMER HAVING ONE END THEREOF ANCHORED TO THE TIMER AND THE OTHER END SECURED TO THE CAM FOR THE SPRING COILS TO FLEX AROUND THE CAM, SAID SHAFT ROTATED IN ONE DIRECTION TO EFFECT ELONGATION OF SAID SPRING ABOUT THE CONTOURED SURFACE OF THE CAM, SAID CONTOURED SURFACE INCREASING IN HEIGHT IN THE DIRECTION OF ELONGATION OF THE SPRING TO MAINTAIN A CONSTANT FORCE IN TENSION IN THE SPRING AND UNIFORMLY ROTATE SAID SHAFT IN THE OTHER DIRECTION TO SAID ONE POSITION THEREOF FOR A LARGE PERIOD OF TIME UNDER THE CONTROL OF SAID TIMER TO RELEASE SAID MEMBER.