Patent ID: 7402028

Claim:
A pressurisation system comprising: a vessel having a chamber for receiving fluid thereinto, the fluid having a pressure, a plunger for enclosing a portion of the chamber to form an enclosure, the enclosure having a volume, and the plunger being movably coupled to and for cooperation with the chamber to reduce the volume of the enclosure, the chamber is shaped and dimensioned for the passage of the plunger therethrough and for the reciprocation of the plunger therewithin, the plunger for reciprocating along a longitudinal axis of the chamber generally parallel to the direction of gravitational acceleration, the plunger having a weight for gravitationally applying a compression force to the fluid to thereby reduce the volume of the enclosure and increase the pressure of the fluid; and a positioning device comprising a hoist assembly and an electric actuator having a brake assembly for interacting with the hoist assembly to impede the reduction of the volume of the enclosure; wherein positioning of the plunger within the chamber is artificially controlled by the positioning device to allow the volume of the enclosure to be pre-determinable.