Patent GB-671033-A (GB)
Title: Improvements relating to ignition devices for internal-combustion engines
IPC: H02N1/08
Filed: 1948-02-17
Abstract: 671,033. Ignition systems. CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE. Feb. 17, 1948 [Feb. 20, 1947], No. 4670/48. Class 7(iv) [Also in Group XXXV] In an ignition device for internal-combustion engines comprising an electrostatic generator, an ignition condenser provided by the capacities between the stationary and moving parts of the generator and a discharge initiating device comprising a rotating electrode or electrodes l<SP>1</SP> 1 , l<SP>1</SP> assembled on the same shaft e<SP>1</SP> as the moving parts of the generator, the rotating electrode or electrodes being adapted to move past one or more stationary electrodes m , m<SP>1</SP> 1  extending through and insulated from an airtight-housing j' enclosing the generator and rotating electrodes, the housing j<SP>1</SP> is filled with a gas under pressure and the shaft e<SP>1</SP> extends through the housing. The generator which comprises two semi-cylindrical, stationary conducting members a<SP>1</SP>, b' is provided with two insulating flanges c<SP>1</SP> d<SP>1</SP> and has its driving shaft e<SP>1</SP> passing through both flanges and carrying two rotors f<SP>1</SP>, f<SP>1</SP>, each rotor consisting of two semi-cylindrical conducting members g<SP>1</SP> h<SP>1</SP> and g<SP>1</SP>, h<SP>1</SP> 1 , respectively, insulated from the shaft. Rotor f<SP>1</SP> 1 , acts as an exciter and rotor f<SP>1</SP> supplies the ignition system. The members g<SP>1</SP>, h<SP>1</SP> are charged under the influence of members a<SP>1</SP> through a brush i<SP>1</SP> that is electrically connected to the housing j', whilst in the position shown brush i<SP>1</SP>ensures that member a' is at the same potential as the housing, which latter is filled with pressurized gas of high-dielectric strength, e.g. nitrogen at a pressure greater than four atmospheres or hydrogen at a pressure greater than eight atmospheres. After half a revolution the members g<SP>1</SP>, h<SP>1</SP> supply a part of their charge through a brush k<SP>1</SP> to the stationary member b<SP>1</SP> ; at the moment of ignition the members g<SP>1</SP>, h<SP>1</SP> supply the discharge to. the sparking plugs, not shown, through the discharge-initiating device. By angular adjustment of the casing j<SP>1</SP> the moment of ignition may be adjusted. If the generator has been standing idle for some time, it may be driven by hand, after disconnecting a claw coupling 0<SP>1</SP>, in order to energize the machine and thus afford easier starting. The sparking plugs may have an insulation resistance of 1,000 ohms, for instance, and the condenser capacity may be as low as 20 E.S.U.'s. Specification 643,579, [Group XXXV], is referred to. The Specification as open to inspection under Sect. 91, comprises also a circuit having a battery a, Fig. 1 (Cancelled), connected to the primary winding of an induction coil b, which latter is provided with a vibrator, the secondary winding being connected across a condenser d and having a selenium rectifier c inserted in one lead; a resistance, not shown, may be placed in series with the rectifier to limit the charging current of the condenser d, whilst one plate of the condenser is connected through a distributer e, which may be of the "jumpspark type," to the sparking plugs h. The other plate of the condenser d is connected to the anode of a gas relay f, the grid of the latter being connected through a high resistance g to the negative terminal of the battery a. Upon actuation of a camshaftoperated switch i the grid is earthed to cause the gas relay to conduct whereupon the condenser d discharges through the selected sparking plug. The distributer e and relay f may be shunted by high resistances (not shown). In a modification, both an electrostatic generator m, Fig. 2 (Cancelled) and an electric motor I which normally drives the generator are housed in an air-tight container n. In an emergency, the shaft o of the generator may be either hand or engine driven. The generator charges a condenser p to a value determined by a regulating device r, such as a gas discharge tube; one plate of the condenser p is earthed and the other is connected to a stationary electrode s in the housing t of a discharge-initiating device that is filled with a pressurized gas such as nitrogen or hydrogen. Inside the housing an enginedriven electrode u is connected to another condenser w that is charged when the rotating electrode u approaches the stationary electrode s, the condenser wdischarging through a sparking plug y when the electrode u reaches another stationary electrode x. Four stationary discharge electrodes x and associated sparking plugs may be provided and by angular adjustment of the housing t the instantof ignition may be adjusted. The discharge-initiating device could be filled with oil or kerosene and the generator casing with fluid instead of gas. This subiect-matter doesnot appear in the Specification as accepted.