| 摘要 |
<p>1,215,123. Mixing apparatus; controlling preparation of pre-polymer. R. ZIPPEL [trading as RICHARD ZIPPBL & CO. K.G.]. 10 Jan., 1969 [21 Feb., 1968], No. 1627/69. Headings B1C and B1X. Apparatus for mixing a multicomponent plastics material comprises at least two mixing chambers 1, 2 with stirrers 13, 131 and component feed lines 6, 7, 10, 11 controlled by valves 4, 5, 8, 9 and supplied by metering pumps 31, 32. There is a restricted passage 3 between the mixing chambers in which may be a screw 14 carried on the common stirrer shaft 12 and arranged to retard flow in the passage. The pumps 31, 32 and valves 4, 5, 8, 9 are controlled by timers 31, 32 and 35, 36 respectively so that pump 32 starts after pump 31 and valves 8, 9 open after valves 4, 5. There may be electric heaters 19, 20 and a cooling coil 21. In an example relating to the preparation of cement-bonded expanded polyurethane, the components of the plastic material are mixed with metallic catalyst such as tin octanoate in chamber 1 and an aqueous suspension of cement added in chamber 2. There may be a third mixing chamber (103, see Fig. 2 not shown) to which a further additive such as sand may be supplied.</p> |
