摘要 |
In order to avoid "water-hammer" which is produced during stoppages of the injection piston (3) because of the time necessary for the action of the valve limiting the maximum pressure (18), of the pressure switch (13) and of the valve limiting the compacting pressure (20), the circuit comprises a pressure accumulator (21) connected to the cylinder (1) in parallel with the pressure switch (13) by the non-return valve (24). By virtue of this accumulator (21) which is preloaded to a pressure less than the maximum allowable pressure in the circuit, fixed by the valve (18), but slightly greater than the pressure to which the pressure switch (13) is adjusted, the pressure in the circuit rises much less rapidly when the injection piston (3) is stopped following filling of the mould, which allows the valve (18) to act in time and to prevent the "water-hammer". <IMAGE>
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