Side flap folding section of a rotary envelope making machine

Claim 1

IN AN ENVELOPE MAKING MACHINE WHEREIN ENVELOPE BLANKS ARE DELIVERED WITH THE SIDE FLAPS LATERALLY EXTENDED FROM BODY PORTIONS OF THE ENVELOPE BLANK AND WITH THE ENVELOPE BLANKS IN A PRE-REGISTERED AND TIMED POSITION TO A FOLDING SECTION WHICH INCLUDES SAID FLAP FOLDERS AT RESPECTIVE OPPOSITE SIDES OF THE MACHINE, AND ENDLESS PERFORATE BELT BETWEEN THE FOLDERS AND HAVING AN UPPER FACE NO WIDER THAN SAID BODY PORTIONS OF THE ENVELOPES, TOOTHED WHEELS FOR CARRYING SAID BELT WITH THE TEETH OF SAID WHEELS MESHING WITH SIMILAR TEETH ON THE BELT, MEANS ROTATABLY CARRYING SAID WHEELS AT ENDS OF THE FOLDING SECTION TO PROVIDE A RUN OF SAID BELT COEXTENSIVE WITH LENGTH OF THE FOLDING SECTION AND IN UNDERLYING REGISTRY WITH SAID BODY PORTIONS OF THE ENVELOPE BLANKS, A FIXED MANIFOLD HAVING SIDE, BOTTOM AND END WALLS PROVIDING AN OPEN TOP SUBSTANTIALLY COEXTENSIVE WITH AND COMPLETELY COVERED BY SAID RUN OF THE BELT, BELT GUIDES ALONG INNER FACES OF THE SIDE WALLS OF THE MANIFOLD FOR SUPPORTING THE EDGES OF SAID RUN OF THE BELT THEREON FOR PROVIDING A SLIDING SEAL BETWEEN THE BELT AND SAID MANIFOLD, MEANS CONNECTED WITH THE MANIFOLD FOR DRAWING A VACUUM IN SAID MANIFOLD FOR PRADUCING A CONTINUOUS SCUTION THROUGH SAID RUN OF THE BELT ALONG THE LENGTH OF THE FOLDING SECTION FOR SEIZING THE OVERLYING BODY PORTION OF EACH PRE-REGISTERED BLANK AS IT IS DELIVERED TO SAID FOLDING SECTION AND FOR MAINTAINING CONTINUOUSLY THE SAME SEIZED HOLD ON EACH ENVELOPE BLANK WHILE THE ENVELOPE BLANKS ARE BEING CARRIED BY THE CONVEYOR ALONG THE LENGTH OF SAID FOLDING SECTON FOR PREVENTING DISPLACEMENT OF THE BLANKS FROM SAID PREREGISTERED AND TIMED POSITION BY SAID FOLDERS WHEN FOLDING THE SIDE FLAPS OVER THE SEIZED BODY PORTIONS, AND BELT SUPPORTING MEANS IN THE MANIFORLD BETWEEN SAID BELT GUIDES FOR COOPERATING WITH THE GUIDES FOR SUPPORTING SAID RUN OF THE BELT WITH THE UPPER FACE IN PLANE WITH THE LINES OF FOLD PRODUCED IN SAID FLAPS.