Patent ID: 7967599

Claim:
A blow molding machine having a valve block ( 102 ) with a stretch rod/blow nozzle ( 104 ) extending through a hole in the valve block ( 102 ), characterized by: a cylindrical bore ( 101 ) formed in the valve block ( 102 ) where the cylindrical axis of the cylindrical bore ( 101 ) is parallel with the stretch rod/blow nozzle ( 104 ) and concentric with the hole in the valve block ( 102 ) and where the cylindrical bore ( 101 ) has a bottom surface; a valve piston ( 110 ) having a generally circular shape with a central hole where the valve piston ( 110 ) is located in the cylindrical bore ( 101 ) of the valve block ( 102 ) with the stretch rod/blow nozzle ( 104 ) passing through the central hole; a sealing surface ( 466 ) located on the valve piston ( 110 ) where the sealing surface ( 466 ) completely surrounds the stretch rod/blow nozzle ( 104 ), the valve piston ( 110 ) configured to move between an open position and a closed position by moving along an axis formed by the stretch rod/blow nozzle ( 104 ); the sealing surface ( 466 ) configured to form a seal that surrounds the stretch rod/blow nozzle ( 104 ) when the valve piston ( 110 ) is in the closed position thereby preventing radial fluid flow into or away from the stretch rod/blow nozzle ( 104 ).