| 摘要 |
PURPOSE:To perform rotation detection and flow rate detection with high reliability by inserting a magnetic body after a ferromagnetic surface treatment into a hollow nonmetallic material and using the material to constitute a rotating body which has magnetism and rotated by the flow of fluid in a flow. CONSTITUTION:When the fluid flows from an entrance 6 to an exit 7, it is made into an axial swivel flow by a fixed vane 8 and the rotating body 9 is rotated by the swivel flow. The rotational frequency of the body is proportional to the flow rate, and the rotational frequency is detected by a magneto-resistance element 11 and processed by a control circuit 14 to calculate the flow rate. The rotating body 9 includes a core bead 15 made of the hollow resin material, which is covered with a ferromagnetic surface treated layer 16 of Fe-Ni alloy, etc., to form the magnetic body; and the outside is further covered with a resin molding layer 17. |
