Valves for controlling flow of pressurized fluid to a tool

A valve for controlling flow of a pressurized fluid to a tool, the valve comprising:

• a manifold having:
• a manifold inlet configured to receive the pressurized fluid from a source;
• a tool outlet configured to discharge the pressurized fluid to the tool;
• and
• a tank outlet configured to discharge the pressurized fluid to a tank;
• a poppet biased into an unseated position in which the pressurized fluid may flow from the manifold via the tank outlet, the poppet being movable into a seated position closing the tank outlet so that the pressurized fluid is prevented from flowing from the manifold via the tank outlet;
• a piston configured to move the poppet into the seated position when the pressurized fluid flows into the manifold via the manifold inlet at a first fluid pressure, wherein the poppet extends into the piston;
• and
• a check valve on the poppet, the check valve being biased into a closed position closing the manifold inlet so that the pressurized fluid is prevented from flowing from the manifold via the tool outlet, the check valve being movable into an open position in which the pressurized fluid may flow from the manifold via the tool outlet when the pressurized fluid flows into the manifold via the manifold inlet at a second fluid pressure which is greater than the first fluid pressure;
• wherein the piston and poppet are coupled together so that when the poppet is in the seated position, the piston is independently movable relative to the poppet so that the poppet may remain in the seated position upon variations in fluid pressure in the manifold.