This device includes a one stage primary piston and a two stage secondary piston in order to avoid increasing the size and weight of theHydraulic Pump with the function of power multiplication. The Hydraulic Pump is sealed by a cover with the piston rod of the primary piston passed tbrough the secondary piston and Hydraulic Pump the cover. Two shutoff pistons actuated by two different springs are as a whole with the cylinder, while two opening pistons are located at the possitions opposite the shutoff pistons.

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