| 摘要 |
<p>A machine for producing metal die castings is disclosed and comprises a crucible (10) that incorporates an injection pump assembly (48) which is mounted in such a way as to clear the upper access of the crucible (10) to facilitate cover (18) sealing and remov ing. The crucible (10) is located in a furnace (32) and is reciprocable to move the injection barrel (44) and nozzle (46) to and from a mold. The injection barrel (44) is immersed in the crucible (10) beneath the level of the molten metal to enhance heat transfer between the barrel (44) and injected metal. The separate injection and valve plungers (50, 52) are located in the pump body in a "V" configuration so that maintenance of these units can be carried out without exposing the top of the furnace to the atmosphere. The injection and valve plungers (50, 52) include sealing means (138) in connection with their actuating mechanisms to avoid molten metal splashing outside of the crucible when they are moving in an injection operation and to prevent the ingress of moisture, hydraulic fluid or the like into the crucible or injection chambers. The apparatus is particularly suitable for use with high melting point alloys such as magnesium.</p> |
