VALVE CLOSING TIMING DEVICE

PURPOSE:To make it possible to time a valve in closing even in the absence of fluid flowing in a valve body by supplying external pressure fluid to an upper piston chamber or lower piston chamber through an external pressure fluid supply pipe. CONSTITUTION:In valve closing, an upper air supply pilot valve 15 is opened by a remote switch 23 to close an upper air discharge pilot valve 20. At the same time, a lower air supply pilot valve 17 is closed to open a lower air discharge pilot valve 21 and also a cutoff valve 103. These operations make the external pressure fluid accumulated in an accumulator 105 work in an upper piston chamber 7 to lower a needle 6 closing a valve body. The signals from a position detector 24 are recorded during the work of valve closing in an oscillorecorder 25 timing the valve in closing.