Abstract: A thread former for the chipless production of a thread has a plurality of pressing lands, which are each arranged at predefined separation angles (T) along a shaping curve. Each separation angle (T) is smaller than or equal to a predefined maximum separation angle (Tmax). For nominal thread former diameters (Da) between 6 mm and 20 mm, the maximum separation angle (Tmax) is determined such that the following condition: Tmax=sin?1((a×NDy+b×ND+c)×2×?); is met for i) 6?ND<10 where a=?0.0008, b=0.00705, c=0.1325, y=2; ii) 10?ND<12 where a=1.7924/(2×?), b=0, c=0, y=?0.408; or iii) 12?ND?20 where a=0.751/(2×?), b=0, c=0, y=?0.104; wherein Tmax is the maximum separation angle and ND is the amount of the nominal thread former diameter (Da) measured in millimeters.
Type:
Grant
Filed:
November 22, 2017
Date of Patent:
June 8, 2021
Assignee:
EMUGE-WERK RICHARD GLIMPEL GMBH & CO. KG FABRIK FÜR PraÄZISIONSWERKZEUGE
Inventors:
Helmut Glimpel, Thomas Berschneider, Jurgen Fenzel