Proportional pressure relief valve

The proportional pressure relief valve, with the assistance of a proportional amplifier, is a continuous, electrically adjustable pressure relief valve.

The control piston has two adjacent areas exposed to pressure. The first area is exposed to the pressure at connection P, the other to connection T. If the magnet is not supplied with electricity, then the piston is fully retracted and the complete passage from connection P to connection T is free. The proportional magnet creates a force proportional to its magnetic current, which moves the control piston according to the balance of the adjacent forces (magnetic force, spring force and pressures).

The control voltage must be in the range 0 V to 10 V. The minimum nominal pressure defines the opening pressure through the spring force at 0 V. The maximum nominal pressure defines the opening pressure at 10 V. The hydraulic resistance relates to the completely opened main stage leading edge.