OPEN VALVE

PROBLEM TO BE SOLVED: To obtain an open valve where occurrence of malfunction caused by foreign matter in a cylinder is suppressed, a valve body is easy to die-cast and material is reduced to reduce costs for manufacturing, by discharging the foreign matter in the cylinder from the cylinder to inside of a secondary side channel in operation of the piston. SOLUTION: In the valve body 1, a primary side channel 2 and a secondary side channel 3 are connected through a communication hole 4, and a cylindrical cylinder 5 is formed with its cylindrical opening facing the secondary side channel 3, with its shaft core coincident with the center of the communication hole 4, facing the communication hole 4 with each other across the secondary side channel. The piston 16 is arranged slidably in the cylinder 5 and divides inside of the cylinder 5 into a piston chamber 5a and an operation chamber 5b. A stem 9 has its one end fixed to the shaft core position of the piston 16, and the other end fitted to a stem fitting recess part 9 of a disk part 7. COPYRIGHT: (C)2007,JPO&INPIT