Patent ID: 6298903
Filing Date: 2001-10-09
Classification: B22D

Abstract:
A valve assembly for venting a diecasting mould of a diecasting machine that is provided with a casting piston located in a pressure chamber for pressing liquid casting material into a mould cavity of said diecasting mould, said diecasting mould being provided with a venting channel communicating with said mould cavity, said valve assembly comprising:a first venting valve communicating with said venting channel, an impact transmitter operationally connected to said first venting valve, said impact transmitter being exposed to and moved by said liquid casting material advancing from said mould cavity into said venting channel, said impact transmitter closing said first venting valve when said impact transmitter is moved by said liquid casting material;a second venting valve communicating with said venting channel; andseparate, independent means for operating said second venting valve,said impact transmitter, said first venting valve and said second venting valve being positioned downstream of said mould cavity;said venting channel including an essentially straight first venting channel portion, said second venting valve being located at the end of said essentially straight first venting channel portion;said venting channel including a second venting channel portion that has corners, said first venting valve being located in said second venting channel portion.