| 摘要 |
<p>537,396. Screw-and-nut gearing. SECURITY ENGINEERING CO., Inc. June 15. 1940, No. 10419. Convention date, Oct. 24, 1939. [Class 80 (iii)] [Also in Group XXVIII] In a screwed well-pipe joint of buttress form, the leading faces 14 of the screw-thread are inclined at an angle of 22 to 25 degrees to the axis of the joint, and collars 18, 20 are provided at the ends of a flush-type joint to take compression. The back faces 16 of the threads are inclined approximately at 10 degrees to a plane normal to the axis. The crests and roots of the threads are rounded so as to leave a small clearance S. Similar screw-threads may be used where a pair of spigots are joined by an external collar.</p> |
