On-off valve and apparatus for performing work

An instant on-off valve comprising:

• a valve body having a main valve chamber and an actuating chamber separated by a partition;
• a valve plunger straddling the partition, the valve plunger having a tapered front end portion positioned within the main valve chamber and a rear end portion positioned within the actuating chamber, the valve plunger having a central through fluid passage extending from the front end portion to the rear end portion;
• a valve seat positioned at a chamber end of the main valve chamber, the valve seat having a central tapered valve port sealably mating with the front end portion of the valve plunger;
• an actuating pin aligned with the valve plunger, the actuating pin having a first pin end portion positioned within the actuating chamber and a second pin end portion positioned outside the actuating chamber, the second pin end portion connected to an actuator which is attached with respect to the valve body;
• a fluid inlet of the valve body in communication with the main valve chamber and with a fluid passage of an energy storage device;
• a fluid outlet of the valve body in communication with the valve port;
• a nozzle in communication with the fluid outlet;
• and
• a check valve assembly mounted within the central through fluid passage preventing fluid flow in a direction from the front end portion to the rear end portion of the valve plunger.