| 摘要 |
810,394. Screw stud and socket fasteners; bolts &c. ZAHODIAKIN, V. F. Jan. 7, 1957 [Sept. 7, 1956], No. 622/57. Classes 44 and 89(1) A fastener, e.g. for securing together parts 19, 20, Fig. 1, comprises a nut 10 secured to part 19 by a cage 13 allowing limited freedom-of-movement for the nut, a longitudinally-slit-sleeve 25 having extermal-threads 26 engaging the nut-threads 24 with a predetermined clearance 42, the sleeve having a different-pitch internalthread 33, e.g. a four-start-thread, engaged by a screw 31. The sleeve-and-nut are held against relative-rotation by a pin 29, Fig. 2, and the pitch-diameter of the screwthreads is larged than that of the sleevethreads. Thus the sleeve engages the screw with a frictional-resistance to turning thereof, and is expanded to reduce the clearance 42. Final tightening of the screw causes a slight aixial-movement of the sleeve relative to the nut, resulting in the threads 24, 26 being wedged together to press the sleeve tightly against the screw, which has a lead-portion 31<SP>1</SP>. The leading- thread of the screw has a major-diameter slightly greater than that of the remainder of the screw-shank, and retains a splitcollar 39 on the shamk, thus securing the screw to part 20. The nut is covered with a dust-cap 21. |
