| 摘要 |
1496976 Position sensing device ILLINOIS TOOL WORKS Inc 20 Oct 1975 [29 Oct 1974] 42946/75 Heading G1N A sensing device comprises a hollow, cylindrical magnetically saturable tube, magnetic means, e.g. two oppositely magnetized magnets 18, 20, so arranged with respect to the tube that the tube is divided into a first, magnetically saturated portion A and a second magnetically unsaturated portion B, the extent of the portions varying in accordance with the relative positions of the tube 16 and magnetic means, and a sensing wire 12 passing through the tube and preferably along or in a direction parallel to its axis for sensing the extent of the portions and hence the relative positions of the tube and magnetic means. The sensing wire may be used on its own in an oscillating circuit or as shown in combination with a diving wire 14, an A.C. excitation signal, in this case, being fed to the sensing wire. Alternatively two spaced co-axial magnetically saturable tubes may be used, the driving wire being tapped between the two tubes and the driving wires in the tubes being connected oppositely, Figs. 4 and 5 (not shown). In a similar embodiment to that last described, the tubes are both part circular and the sensing device is of circular configuration Fig. 6 (not shown). |
