| 摘要 |
1312189 Rolling threads REED ROLLED THREAD DIE CO 19 April 1971 [3 April 1970] 25383/71 Addition to 1250413 Heading B3M [Also in Division F2] A self-locking screw 2 compoises a massive rib 14 on one flank only-preferably the non- pressure flank 12- of the thread 18, the rib having an outer wall 36 commencing along an arcuate line intermediate the pitch line 39 and the thread root 26 and an inner wall 38 commencing at an arcuate line 33 nearer the intersection of the pitch line 39 and the transverse mid-section 34 of the thread than to the original line 30 of the one flank, the outer and inner walls 36, 38 intersecting on an arcuate line generally midway axially between the crest and root of the one flank, a third wall 40 sloping from the base of the inner wall 38 toward the other thread flank 8 to terminate at or near the thread crest. The rib is bent over by the nut thread to lock by friction (Fig. 4, not shown). The rib may be continuous for one or more complete turns, or discontinuous. The leading and trailing ends of the rib(s) are faired into the flank 12 (as at 46, Figs. 1, 2, not shown). The outer wall 36 has a height of at least half the thread depth. The walls 38, 40 may be slightly convex and concave respectively. The rib is formed from the basic thread by coldrolling. |
