Patent GB-144622-A (GB)
Title: Method and apparatus for determining or indicating geographical location of a stationary or moving body
IPC: G01S19/51
Filed: 1920-05-25
Abstract: 144,622. Conners, W. W. June 12, 1919, [Convention date]. Course-recording apparatus.-Relates to apparatus controlled by wireless waves for indicating and recording on a chart carried by a moving body the course over which it travels. The apparatus may also be adapted to record the time certain points on its course are reached. A plurality of rods 48, 45 and 48<1>, Fig. 1, are positioned above the chart, converging to a common point 49, and sliding through pivoted guides A<3>, B<3>, C<3>, which are fixed at points whicn represent the positions of three known wireless transmitting stations on the chart. Apparatus controlled by the waves received by a rotating directional receiving station S on the body, automatically varies the angles between the rods in accordance with the manner in which the body varies its angular relation with the transmitting stations, in order that the point 49 shall at all times indicate the position of the moving body on the chart. The receiving station S is of the Bellini-Tosi directional type comprising a non-directive antenna 1 and a directive antenna 2 in series with an inductance 3, which is coupled to a rotatable inductance 4, forming part of an intermediate tuned circuit completed through the primary 111 by means of the brushes 14. The antenna 1 is fixedly coupled to the intermediate circuit by an inductance 6, to which it is connected by the brush 12 and disk 11. The disks 11, 13, 13<1>, and the parts associated with them, are rotated at a constant speed by the motor 10. When the coil 4 is pointing towards a transmitting station A, Fig. 4, oscillations of maximum amplitude are induced in the intermediate circuit, which are amplified by the valves 16 and charge the condenser 17<1>. As the coil 4 moves out of the position of maximum intensity the charge on the condenser 17<1> operates the magnet 19, which is arranged to operate at some general relative position of the coil, by means of controller 122. The operation of the magnet 19 momentarily closes a circuit through a more powerful magnet 22 which rotates the shaft 23 one-third of a revolution. Spaced at equal angular distances around the shaft are contacts A', B<1>, C', corresponding in number to the number of transmitting stations. The arm 27 engages with contact A<1> and remains in contact until the shaft is again rotated, by the coil 4 coming into a position of maximum intensity of siguals from the station B. The current which will flow through the wattmeter A<2> is therefore directly proportional to the angle x between the directions of the two transmitting stations A and B, assuming the body to be in a position P as indicated in Fig. 4. Further, the arm 27 will remain in contact with contact B' until maximum signals from C cause the shaft again to be rotated, and current will flow through the wattmeter B<2> whilst the coil 4 is turning through the angle x<1> between the bearings of the stations B and C. These angles x and x' are reproduced between the roads 48, 45, 48<1> in the following manner. The pointers 38, 38<1> of the wattmeters A<2>, B<2> travel over resistances 39, 39', and a part of these resistances, depending upon the swing of the needles, is included in one circuit of the ratio galvanometers 42, 42<1>. Corresponding resistances 44, 44<1> are carried by the rod 45, and brushes 51, 51', carried by the rods 48, 48<1>, vary the portions of the resistances 44, 44<1> which are included in the other circuits of the ratio galvanometers. If the angle between the rods 48 and 45 is equal to the angle x, the resistances in the two circuits of the galvanometer 42 are equal, and the needle 54 is not deflected. When, however, the body reaches a position P', this angle is decreased. The current through the wattmeter A<2> decreases proportionately, and diminishes in like proportion the resistance in the right-hand circuit of the galvanometer 42. The circuits of the latter being unbalanced, the pointer 54 is deflected to the right, and engaging with one of the contacts 60, operates the reversible motor A' to move the rod 62 until the circuits are again balanced and the new angular relation between the stations A and B is reproduced by the rods 48 and 45. The wattmeter B<2>, galvanometer 42<1>, and motor B<4> operate in a similar manner to reproduce the angular relation between the stations B and C. It is essential that a constant predetermined quantity of electricity shall flow from the battery 31 during one complete revolution of the shaft 23. The total of the readings of the meters A<2>, B<2>, C<2> gives the rate of discharge of the battery 31 per revolution, and to determine if this is the correct rate another wattmeter 70 is provided. The speed indicator needle of the speedometer 79 moves over a resistance 78 and so regulates the flow from the battery 75 that the reading of meter 70 is at any time the total of what meters A<2>, B<2> and C<2> should read. In order to synchronize the speed of the coil 4 and shaft 23 an indicator 83 is provided to show the discrepancy when the speed of either changes. In order to check any discrepancy due to a turning movement imparted to the receiving antenna by the moving body, a second complete set of apparatus is provided and operated by a second coil 4'. By rotating coil 4<1> in the opposite direction to coil 4 any discrepancy will indicate itself in the readings of the corresponding wattmeters of the two systems. Further, in order that coils 4 and 4<1> only receive one maximum intensity per cycle from any one transmitting station, the collecting rings 13, 13<1>, 129, and 130 are insulated over half of their periphery. The time and course recording means consists of a yieldable arm 88 carried by one of the rods 48, 48', 45, or 62, and fitted with a pencil 89 which travels over a chart 90 to record the course. The arm 88 carries a stamp 93 which may be brought down on the map to record the time &c. by means of an electro-magnet 94, whose circuit is completed at predetermined times or positions by a clock 95 or similar means.