| 摘要 |
684,846. Screw and nut gearing. NATIONAL RESEARCH DEVELOPMENT CORPORATION. Nov. 28, 1950 [Dec. 6, 1949], No. 31335/49. Class 80 (iii). A nut member is formed in two spring-pressed parts 2, 3 having pads 2a, 3a of a resilient, readily deformable material such as cork, rubber, fibre, leather or balsa wood, which engage under the pressure of a spring 6 with the thread x of a screw member 5. The threads on the pads 2a, 3a may be cut or preformed or they may be produced merely by the resilient contact with the screw thread x. The device is particularly applicable to mechanism for the cutting or ruling of screws, helices, scales or diffraction gratings such as y on a mandrel 5 which also carries the screw thread x, a reproduction of the thread being obtained by a cutting or marking point 21 on a guided carriage 11, 12, 16 carrying the nut 2, 3, corrected however for local inaccuracies of the thread by reason of the resilient thread of the nut. |
