| 摘要 |
510,230. Bolts etc.; screw fastenings. BUSBY, D. Feb. 28, 1939, No. 6559. Convention date, March 1, 1938. [Classes 44 and 89 (i)] A screw fastening for securing cowlings and like uses comprises a screw 32 rotatably mounted in the part 12 to be secured to part 10, the screw passing thrcugh a registering aperture in part 10 into engagement with a coil spring 16 secured by a rivet 30. As shown the apertures are countersunk at 22, 29 to conform with the screw head 42 and the aperture in part 12 has a wear-resisting liner secured by folding over at 24. The liner is crimped to provide projections 20 adapted to engage in notches in the periphery of the screw head, two of these notches being formed at the ends of a transverse slot 27 which receives a screw driver, others being provided intermediately. The screw is retained in part 12 by a split ring 36 and the head may have a groove carrying a leather &c. washer 40 to make fluid-tight joint. A fibre sheet 46 may be interposed between parts 10, 12, and secured to the latter. The spring has a conical portion merging into a cylindrical portion, the latter engaging the threads of the screw and the former acting as a compression spring and also allowing slight lateral movement to compensate for faulty registration. |
