| 摘要 |
<p>1490500 Mixing apparatus ELASTOGRAN MASCHINENBAU GmbH & CO 29 June 1976 [29 Aug 1975] 27081/76 Heading B1C A mixing device for mixing together the components of a foamed plastics material comprises a mixing chamber 1, supply ducts 3, 4 for the components of the plastics material which open into the chamber 1 and a piston 7 reciprocable in the chamber 1 to permit or prevent flow of the components into the chamber 1 through the ducts 3, 4 the piston 7 having a passage 8 for independent supply of air into the chamber 1 of air. The passage may as shown be a bore in the piston but may alternatively be provided by one or more grooves in the piston. The bore 8 may terminate in a replaceable nozzle (9 Fig. 3 not shown). Grooves in the piston provide for recirculation of the components via ducts 5, 6 when the piston is in its forward position (Fig. 1 not shown). The air flow in passage 8 is controlled by a valve 8 and flow controller 17 and means are provided so that after the supply of components has been interrupted, the flow of air is established before the supply of the components begins.</p> |
