| 释义 |
ˈback-rest
[back- A. 3, 4.]
1. A contrivance to support or ease the back of a person when seated or engaged in manual work (e.g. at a lathe). Also, provision for such support.
1859Holtzapffel Turning IV. 20 The turner using the pole lathe..requires the back rest to steady and support his body. 1909Daily Chron. 13 Nov. 9/6 Neither does it mean that the passengers have their comfort curtailed in respect of insufficient back-rest.
2. A guide attached to the slide-rest of a turning-lathe and placed in contact with the work to steady it.
1881in Imp. Dict. 1907Perrigo Mod. Amer. Lathe Practice 164 There are two classes of these rests which may in a general way be called ‘center rests’ and ‘back rests’. The center rests usually have jaws bearing upon the work at three points spaced equally around the circle, while a back rest bears upon the work generally at the back and on top only.
3. Weaving. A bar over which the warp passes from the warp-beam.
1894T. W. Fox Mech. Weaving 369 Each warp beam..must be parallel with back rest, breast beam, and taking-up roller. |