| 摘要 |
The invention relates to an apparatus for pressure casting of metal parts which possibly contain fibres of ceramic material. The apparatus includes a cold chamber, and comprises a lower fixed plate 1, an upper movable plate 2, and a die 3 disposed between the upper plate and the lower plate, with the lower plate being provided with an injection means for liquid metal comprising an injection sleeve 5 having a piston 6 supported on a rod 7 slidable in the sleeve. The metal is contained in a sealed vessel connected to the injection sleeve by a conduit 9 by way of an orifice 8 in the sleeve, with a gas inlet in the vessel connected to a source of gas for selectively placing the liquid metal in the vessel under a gas pressure P2 which causes the flow of liquid metal in the conduit towards the sleeve. A second gas inlet is located in the conduit near the orifice, this second gas inlet able to selectively create a gas pressure P1 in a pocket adjacent to the inlet, depending on the position of the piston and the gas pressure P2. |
