| 摘要 |
A magnetic detection device for detecting the position of a movable member which is associated with a piece of magnetic material, the movable member being displaceable in a non-magnetic tube. A detection unit fixed outside the tube and including a permanent magnet with pole pieces directed towards the tube and extended portions extending away from the tube. The extended portions may be either in a plane parallel to or perpendicular to the axis of the tube. A dry reed relay is fixed relative to the pole piece with its ends facing the extended portions remote from the magnet. The extended portions may extend from opposite sides of the tube in which case the extended portions are perpendicular to the axis of the tube and the axis of the reed relay has a normal parallel to the axis of the tube. Alternatively, the reed relay is disposed parallel to the axis of the tube in which case the pole pieces are disposed on the same side of the tube. Alternatively, for detecting the direction of displacement, two double detection units are provided in superposed relation with their magnets in repelling relation. |
