Press forming machine for glass

摘要

Inert gas is supplied from a supply source to the interior of a forming chamber through lines and gas supply routes. Variable flow control valves are provided in the middle of the lines and are controlled by a command from a control unit. The variable flow control valves vary pressure or flow rate of the inert gas in accordance with a command value to be sent every moment from the control unit such that the pressure or flow rate gradually reach a target value. According to the present invention, the pressure in the forming chamber is not varied abruptly when supply of the inert gas is stopped or the setting of flow rate thereof is changed. As a result, fluctuation in output of a load cell 8 b can be suppressed and high precision of pressing force can be secured.