Patent GB-298934-A (GB)
Title: Improvements in or relating to apparatus for use in steering moving vehicles, the improvements being also applicable to azimuthal stabilisers
IPC: G01C17/36
Filed: 1927-06-17
Abstract: 298,934. Gray, J. G. June 17, 1927. Earth-inductor machines. - An inductor compass depending for its action on currents induced in a coil rotating in the earth's field, as described in Specification 142,164, [Class 37, Electricity, Measuring &c.], has the coil-carrying frame mounted on a gyrostatic stabilizer of the type described in Specification 130,697, [Class 97 (iii), Thermometers &c.], and supported on the moving vehicle in a position remote from electromagnetic apparatus, and the axle of this frame or of the brush-carrying frame is connected by gearing to a second axle mounted at the steering position so as to indicate the position of the first frame. As shown in Fig. 1, a coil 1 is mounted on a vertical axle driven by an air fan 4 and is connected to a two-part commutator on which press brushes 7 carried by brush-holders 7<1> on a worm-wheel 9 operated by a worm 10 so as to set the brushes for steering in any desired direction. The brushes mav consist of small wheels spring-pressed on to the commutator. In the modification shown in Fig. 7, the spinning coil 35, in two parts, is mounted on a gyroscope wheel 30 driven by air jets impinging on vanes 33, and is connected to a two part commutator 5. On this press brushes 7 carried by the wormwheel 9 driven by the worm 10. Driven by the air dragged round by the gyroscope wheel 30 is a fan 38 driving, through reduction gearing 39 - - 42, a ball erector 44. The whole system is mounted in a frame 46 provided with pivots 47 which are mounted in bearings in a surrounding gimbal frame. The ball erector 44 maintains the axis of spin of the flywheel 30 vertical, and is described in Specification 130,697, [Class 97 (iii), Thermometers &c.]. The Provisional Specification describes a further modification in which the spinning coil is set with its axis horizontal, the brushes being carried by a frame turning on an axis in line with that about which the coil rotates. The line of the brushes is maintained vertical and a direct-current galvanometer relay is connected to the brushes. Under these conditions the relay is not affected by currents induced in the coil due to its motion with respect to the vertical field of the earth, which may be neutralized by magnets carried by the coil-supporting frame as described in Specification 142,164, [Class 37, Electricity, Measuring &c.]. When the axis of the coil is North and South, no current passes through the relay, but when the axis is East and West, a maximum current passes through the relay. The relay controls a servo-motor which turns the coil, with its axis horizontal, about a vertical axis until the current passing through the relay is zero, the axis of the spinning coil then pointing North and South. The spinning coil may be wound on the wheel of a gyroscope having its axis horizontal and rotated by means of a turbine wheel driven by air derived from the periphery of the gyroscope casing. The brushes are connected to a relay which applies couples to the gyroscope in such a manner that the coil is brought into the position in which zero current passes through the relay. These couples may be set up by jets of air released from the periphery of the gyroscope, or weights carried by the system may be moved with respect to the line of the fork bearings.