| 摘要 |
<p>1,242,930. Cutting by liquid jet. N. C. FRANZ. 26 Sept, 1969 [1 Oct., 1968], No. 47407/69. Heading B4B. [Also in Division F1] A method of cutting soft material by a high velocity liquid jet comprises selecting a suitable soft material e.g. cardboard, or nylon or cotton fabric, which heats at the edges of the cut due to the passage of the liquid therethrough, providing a high velocity liquid jet with sufficient energy to cut through the material as it is fed through the jet to produce cutting at a rate such that the jet liquid retained at the point of cut volatilizes from the cut within a short period of time due to the heating of the point of cut by the high velocity liquid jet. The apparatus for producing the high velocity jet comprises an hydraulic pump 12 driven from an electric motor 11 and feeding liquid from a reservoir 15 to one or other side of a piston 18a via a relief valve 16 and four-way valve 17. The piston 18a is provided with a ram 19 movable in a cell 20 into which the liquid, such as water, is fed; the liquid passes from the cell to a nozzle 22 via a two-way valve 21. The material is mounted on a table 24 having an opening for the passage of the jet and moved at a selected speed by means 25, 26. Various examples of the material, jet pressure and nozzle sizes and feed speed are described.</p> |
