Flap folding apparatus

Claim 1

A BOTTOM FLAP FOLDING MECHANISM FOR AN ENVELOPE MAKING MACHINE IN WHICH THE ENVELOPE BLANKS ARE DELIVERED TO THE FOLDING MECHANISM WITH SIDE FLAPS FOLDED AND GUMMED AND WITH THE BOTTOM FLAPS LEADING, SAID FOLDING MECHANISM INCLUDING UPPER AND LOWER FEED ROLLERS IN THE PATH OF THE BLANKS FOR PASSING THE BLANKS THEREBETWEEN, A GUIDE ROLLER HAVING A CYLINDRICAL SURFACE WITH THE UPPER PORTION THEREOF ABOVE THE PATH OF THE BLANKS EMERGING FROM BETWEEN THE FEED ROLLERS FOR DIVERTING THE BOTTOM FLAPS OF THE BLANKS UPWARDLY OVER THE GUIDE ROLLER, SAID LOWER FEED ROLLER HAVING A PERIPHERAL PORTION SPACED IN FIXED RELATION FROM THE CYLINDRICAL SURFACE OF THE GUIDE ROLLER TO PROVIDE A PASS THEREBETWEEN ACCORDING TO THE THICKNESS OF THE BLANKS, A SUBSTANTIALLY FLAT GUIDE MEANS HAVING ONE END EXTENDING UNDER THE GUIDE ROLLER TO CARRY THE BLANKS THEREON AWAY FROM SAID PASS TO ALLOW ABSORPTION OF THE GUM INTO THE MATERIAL OF THE BLANKS, AND UPPER AND LOWER CREASING AND PRESSING ROLLERS SEPARATE FROM THE FEED AND GUIDE ROLLERS AND LOCATED AT THE OTHER END OF THE FLAT GUIDE MEANS, SAID PORTION OF THE LOWER FEED ROLLER HAVING MEANS FOR SEIZING A BLANK TO INITIATE A FOLD IN THE BOTTOM FLAP AS THE SEIZED PORTION OF THE BLANK IS CARRIED DOWNWARDLY UNDER THE GUIDE ROLLER AND THROUGH SAID PASS WITHOUT PRESSING THE BOTTOM FLAP INTO FIRM SEALING CONTACT WITH THE SIDE FLAPS WHILE THE BLANK IS PUSHED ACROSS THE SUBSTANTIALLY FLAT GUIDE MEANS BY THE FEED ROLLERS FOR BRINGING THE FOLD INTO ENGAGEMENT WITH THE CREASING AND PRESSING ROLLERS FOR CREASING THE FOLD AND FIRMLY PRESSING THE BOTTOM FLAP INTO SEALING CONTACT WITH THE GUMMED SIDE FLAPS.