METHOD FOR MANUFACTURING PRESS MOULDS FOR PRODUCTION OF INVESTMENT PATTERNS OF NONCIRCULAR GEAR WHEELS Russian patent published in 1997 - IPC

FIELD: foundry; manufacture of foundry auxiliaries intended for press-molds in production of investment patterns of noncircular gear wheels. SUBSTANCE: method involves installation of processing datum surface, electroerosion cutting-out of ring gear of die, manufacture of punch, assembly of die and cover with the help of pins with holes for them making in cover of sign core hole by drilling with the help of jig mandrel with external shape matching internal shape of die, punch centering and installation in socket of die with the same clearance over the entire perimeter. Punch is made from one blank simultaneously together with die by electroerosion cutout. Central hole in punch is made during its manufacture by electroerosion cutout. In this case, punch is used as jig mandrel for making hole in cover. Similar gap between die and punch is made with the help of at least five round pins with diameter equals to the gap width. Pins are installed in gap between punch and die square to their end faces so that three of them are located within tooth point or spaced at the same distance over perimeter of ring gear, and two other pins on diametrically opposite sections of gap within unlike side surfaces of teeth. EFFECT: higher efficiency. 2 cl, 6 dwg