Patent GB-247175-A (GB)
Title: Wireless distant control system
IPC: G08C19/12
Filed: 1926-01-28
Abstract: 247,175. Soc. Leroy, Lajoux, et Cie. Feb. 5, 1925, [Convention date]. No Patent granted (Sealing fee not paid). Controlling and actuating sluice-gates; signalling to or from distant trains; distances, determining; modulating systems; thermionic generators.- In a distant control system employing wireless, a movement of the apparatus or a. change in phenomena causes a variation in the frequency or of the modulation frequency at the transmitter, the reclining station being provided with a. follow-up tuning device regulated automatically by the received waves and so arranged that its regulation gives the desired control either directly or through relay devices. The application to the control of sluice gates is shown in Fig. 9. A central generating station A is provided with an oscillation generator 60 the frequency of which depends on the power requirements of the distribution system and controls a water gate 61 at a substation B. The receiving circuits 35, 36 are tuned on either side of the initial wavelength of the transmitter and variation of the latter to the wavelength of one of the circuits 35, 36 causes the actuation of the corresponding relay 40, 41 controlling a motor 45 operating the gate 61 and the tuning condensers 46, 47 so that the gate is adjusted and also the wavelengths of circuits 35, 36 to values on either side of the new wavelength of the transmitter. A transmitter 67 at the substation B may have the wavelength varied by the movement of the gate, the flow of water or the like to give an indication at the central station A by means of a receiver 70. In a railway system, Fig. 8, comprising tracks 50, 51 each train may have a transmitting station, the wavelength of which is determined by a condenser connected with a distance recorder. A Morse modulation may be superimposed to identify the train, modulation being effected by a cam actuated switch arranged to short-circuit a portion of the inductance in the oscillatorv circuit of the generator. A heterodyne receiver on each train may be provided so that it may determine its distance form another. Signals may in addition be transmitted to trains from stations 55 preferably by damped waves. The transmitter on the train is arranged to actuate apparatus disposed on the line, on the arrival of the train at a predetermined point, for instance a control at a level crossing 57 or other position on the track by means of a receiver 56. A number of modulations may be superimposed on a single carrier wave to give a number of indications. The transmitter may have an oscillating or wobbling frequency to simplify reception which may be produced by a capacity variation which is effected by the oscillation of one plate of a condenser by an electromagnet. Alternatively a variable inductance may replace the variable condenser. Holding devices may be employed to enable movements to be completed and to allow for time lag. The condenser used for controlling frequency may be formed so that angular movements are proportional to the frequency variation. Fig. 3 shows a thermionic generating system the frequency of which is varied by the variation of an electromotive force or a resistance arranged between the terminals A, B. The grids and plates of the valves G1, G2 are reciprocally coupled by condensers C1, C2, and the grids are connected to the filaments through condensers C3, C4 and resistances r1, r2. This arrangement may be used to transmit the variations in resistance of a, wire due to temperature or of a liquid column due to chemical reaction or concentration or of a photo electric cell due to light variations as a variable frequency in the output L. The Specification, as open to inspection under Sect. 91 (3) (a) comprises also the use of acoustic, ultra acoustic, or light waves in place of wireless waves for effecting the control and variation of the energy, rythm, modulation, or time intervals between the modulation, or rythm may be used to effect the control. This subject-matter does not appear in the Specification as accepted.