Work feeding mechanism for sewing machines

Claim 1

IN A SEWING MACHINE HAVING A CASING INCLUDING A WORK SUPPORTING BED, AND A BRACKET ARM OVERHANGING SAID BED, A PRESSER DEVICE CARRIED BY SAID BRACKET ARM AND BIASED TOWARD SAID BED, A FEED DRIVE SHAFT JOURNALED IN SAID BED, MEANS DRIVEN BY SAID SEWING MACHINE FOR IMPARTING ROTARY MOTION TO SAID FEED DRIVE SHAFT IN ONE DIRECTION OF ROTATION, A FEED WHEEL SUPPORTING FRAME JOURNALED FREELY ON SAID FEED DRIVE SHAFT, A FEED WHEEL JOURNALED ON SAID FRAME ON AN AXIS SUBSTANTIALLY PARALLEL TO THAT OF SAID FEED DRIVE SHAFT, A SPROCKET FIXED FOR ROTATION WITH SAID FEED WHEEL, AN IDLER SUPPORTING ARM CARRIED BY SAID FEED WHEEL SUPPORTING FRAME, AN IDLER SPROCKET JOURNALED ON SAID IDLER SUPPORTING ARM ON AN AXIS SUBSTANTIALLY PARALLEL TO THAT OF SAID FEED DRIVE SHAFT, MEANS FOR SECURING SAID IDLER SUPPORTING ARM RELATIVELY TO SAID FEED WHEEL SUPPORTING FRAME IN SELECTED ANGULAR POSITION ABOUT THE AXIS OF SAID FEED DRIVE SHAFT, MEANS FOR SECURING SAID FEED WHEEL SUPPORTING FRAME RELATIVELY TO SAID SEWING MACHINE BED IN SELECTED ANGULAR POSITION ABOUT THE AXIS OF SAID FEED DRIVE SHAFT TO POSITION SAID FEED WHEEL IN OPPOSITION TO SAID PRESSER DEVICE, A DRIVE SPROCKET FAST ON SAID FEED DRIVE SHAFT, AND A TIMING BELT ENTRAINED ABOUT SAID SPROCKETS FOR IMPARTING ROTATION TO SAID FEED WHEEL UPON ROTATION OF SAID FEED DRIVE SHAFT.