| 摘要 |
1,191,375. Screw and nut gearing. FRIEDRICH DECKEL PRAZISIONS MECHANIK & MASCHINENBAU. 9 Oct., 1968 [23 Oct., 1967], No. 47957/68. Heading F2Q. Reverse rotation of a lead screw 16 in a fixed ball-nut 18 to lower a machine tool knee 10 is braked by a slip coupling 38 mounted on the lead screw driving shaft 24 and connected to the non-rotary knee by a one-way jamming roller clutch 32. For normal reverse rotation, the friction force of slip coupling 38 must be overcome. The torque at which the coupling 38 will slip depends on the thrust transmitted by bevel gears 20, 22 on the screw and shaft 24 respectively, and thus depends on load. In Fig. 2 (not shown), an additional spring-loaded slip-coupling (44) is mounted in parallel with coupling 38 to increase the slipping torque by a constant amount dependent on the springs but not the load. |
