| 摘要 |
<p>The screw (104) of a clamping or pressing device, such as a vice or press, passes through a sleeve (111) carrying a thread of different pitch, and engages one (102) of the parts of the device directly and the other (103) via the sleeve, so that the relative movement of the parts of the device is the sum of those due to the sleeve and the screw when they are rotated separately. Using a coarse pitch for the screw and a fine pitch for the sleeve thread, or vice versa, allows rapid initial movement together with high clamping force. The invention is applicable to presses and to various types of vice. A vice according to the invention may be provided with an additional clamp for holding a pipe or rod vertically.</p> |
