Patent ID: 7712464

Claim:
A valve for paint ball guns, comprising: a case having a first chamber, a second chamber and a third chamber defined in the case, an inlet and an outlet respectively through a wall of the case, the inlet communicating with the first chamber and the outlet communicating with the second chamber; a first piston rod being a hollow and tubular member and received in the case, a first piston ring mounted to the first piston rod and movable between a first position and a second position thereof, the first piston ring sealing communication between the first and second chambers when the first piston ring is in the first position, the first and second chambers being in communication with each other when the first piston ring is in the second position; a second position ring connected to the first piston rod and separating the second and third chambers, a fourth chamber defined in the first piston rod and communicating with the third chamber; a second piston rod having a first end received in the first piston rod, an introduction hole defined through a wall of the first piston rod and communicating with the fourth chamber, a third piston ring connected to the second piston rod and located in the fourth chamber, the third piston ring being movable between a first position and a second position, the introduction hole being sealed by the third piston ring when the third piston ring is at the first position thereof, the introduction hole being opened by the third piston ring when the third piston ring is at the second position thereof, and a driving member pushing a second end of the second piston rod to move the second piston rod from the first position to the second position thereof so that pressurized air in the first chamber enters into the fourth chamber and the third chamber via the introduction hole to move the first piston rod from the first position to the second position thereof.