| 摘要 |
The pressure control method is used where the filler is in the form of a paste or slick pressed by a pump into a press-matrix via a filler line and valve. A hydraulically actuated material blocking valve (3) and a pressure sensor (8) are provided between the filler line (2) and the matrix (4), to enable the pressure sensor (8) to sense the build up of filling pressure in the mould (4). When the required max. pressure is attained, a timer (12) is actuated to hold the filling pressure retention time constant via an electronic-hydraulic control circuit (9). Run-down of the timer (12) triggers upward movement of the lower pressing piston (6), with the pressure at the sensor again increasing and the first pressure threshold rising above a normal pressure fluctuation is used as a signal to close the material blocking valve (3). |
