Drive for rotary feed attachments for sewing machines

Claim 1

AN ATTACHMENT FOR USE WITH A SEWING MACHINE OF THE TYPE INCLUDING A DRIVE, A THROAT PLATE HAVING A FEED SLOT AND INTERMITTENT FEED MEANS OPERATIVE THROUGH SAID FEED SLOT FOR BOTTOM FEED OF AN ASSEMBLY TO BE STITCHED, SAID ATTACHMENT INCLUDING AT LEAST ONE ROTARY FEED WHEEL ADAPTED TO BE DISPOSED IN OPERATIVE RELATION TO THE THROAT PLATE FOR FRICTIONAL CONTACT WITH THE UPPER SURFACE OF THE MATERIAL BEING FED THROUGH THE MACHINE BY THE INTERMITTENT FEED MEANS, A FLEXIBLE COUPLING OPERATIVELY CONNECTED AT ONE END TO SAID ROTARY FEED WHEEL, AND A SLIP CLUTCH OPERATIVELY CONNECTED TO THE OTHER END OF SAID FLEXIBLE COUPLING AND ADAPTED TO BE CONNECTED TO SAID DRIVE, SAID SLIP CLUTCH INCLUDING A CLUTCH SHAFT SECURED TO SAID FLEXIBLE COUPLING, A DRIVING GEAR JOURNALED ON SAID CLUTCH SHAFT, A STACK OF CLUTCH DISCS, MEANS SPLINING ALTERNATE ONES OF SAID CLUTCH DISCS TO SAID DRIVING GEAR, MEANS SPLINING THE REMAINING ONES OF SAID CLUTCH DISCS TO SAID CLUTCH SHAFT, A SPRING ENCIRCLING SAID CLUTCH SHAFT AND BEARING AGAINST SAID STACK OF CLUTCH DISCS, AND MEANS FOR SELECTIVELY ADJUSTING THE BIAS EXERTED BY SAID SPRING ON SAID STACK OF CLUTCH DISC SO THAT THE SLIP OF SAID CLUTCH MAY BE ADJUSTED IN ACCORDANCE WITH STITCHING REQUIREMENTS TO PREVENT MOVEMENT OF SAID ROTARY FEED WHEEL BEFORE THE OPERATIVE FEED STROKE OF THE INTERMITTENT FEED MEANS.