FLOW RATE MEASURING INSTRUMENT WITH REVERSE FLOW PREVENTING FUNCTION AND FLOW RATE CONTROLLER WITH REVERSE FLOW PREVENTING FUNCTION

摘要

PROBLEM TO BE SOLVED: To eliminate the setting space of a check valve, and contrive the space saving of a gas unit by providing the check valve preventing the reverse flow of gas in the body of a flow rate measuring instrument. ;SOLUTION: A valve chamber 11 coaxial with a gas passage is formed in the downstream side of the laminar flow bypass part 8 of the body 1a of a flow rate measuring instrument 1, body 15 in a ground 13 fitted in a valve chamber 11 is slid, and gas is passed to the side of an outlet 5 through a gas passing hole 14. In addition, a coil spring 18 urged in the direction (valve opening direction) of seating the valve body 15 on a seat packing 12 in opposite to the flow direction of gas is provided. When the check valve 10 is constituted in the above constitution, gas is flowed to the side of the outlet 5 through a gas passage hole 14 by pushing the valve body 15 in the direction (valve opening direction) being from the packing 12 in opposition to the coil spring 18 by gas pressure. When gas is reversely flowed from the side of the outlet 5, the valve body 15 is seated on the packing 18 by force of the spring 18 to prevent reverse flow.;COPYRIGHT: (C)1999,JPO