| 摘要 |
1,263,947. Rolling threads. ALLIED PRODUCTS CORP. 29 April, 1969 [29 April, 1968], No. 21708/69. Heading B3M. [Also in Division F2] In order to produce a locking thread formation 7 on a bolt 5 (Fig. 1, not shown), a thread rolling die (Fig. 5, not shown) has an insert 14 (Fig. 7, not shown), a section 15 of which replaces a V- form crest 11. The section 15 is arcuate both transverse to the threads, the radius being ¢ to 1 thread pitch, and along the threads, the radius being approximately twice the major thread diameter of bolt 5. Section 15 deforms the flanks of two adjacent threads in opposed axial directions to give mirror image concave surfaces (Fig. 4, not shown). |
