Hydraulic operated mould closing system - using a low pressure liquid for initial movement and high pressure locking fluid

摘要

Injection moulding appts. has a two part mould, one part of which moves relative the other to open and close the mould. A hydraulic motor operates the movable part of the mould. Relatively low pressure liq. flows to the motor during closing movement, and then high pressure liq. is supplied to the motor as the movable part reaches the closed posn. to exert a substantial force on the closed mould. Arrangement provides economical use of high pressure fluid to provide rapid movement of the movable mould part and also to provide high moulding pressure.