GB190717463A - Improvements in or relating to Magneto Electrical Ignition Devices for Internal Combustion Engines or the like. - Google Patents

Abstract

17,463. Postans, A. J. July 30. Gas and like engines, igniting in. To prevent sparking at the contacts of the distributor used in the igniting systems of multicylinder engines in which the current is supplied by a magneto, a circuit in parallel with that of the operating sparking-plug is closed just after ignition and is kept closed until the current in the magneto armature is reversed and the next sparking-plug for duty is connected in circuit with the magneto. In the diagram shown in Fig. 1, the numerals 1, 2, 3, 4 represent brushes connected respectively to the explosion, compression, exhausting, and suction cylinders of a four-cylinder engine. The switch is driven from the engine as usual, and has a firing strip a and an auxiliary or shunt bar b. Sparking will occur when the strip a is touching one of the brushes 1, 2, 3, 4 and the strip b is at the same time free from these brushes. Before the strip a leaves the brush 1, the strip b is on the brush 3 so that the current is divided and sparking at the brush 1 prevented. The strip b remains on brush 3 until the strip a reaches the brush 2, and before the electromotive force is again a maximum the strip b leaves the brush 3, so that the whole of the igniting current is utilized in the cylinder connected to the brush 2. A distributor for carrying out this method is shown in Fig. 4. Current from the magneto is conveyed to the circumferential strip f through a spring-loaded ball f and binding-screw f The firing bar a and shunt bar b are connected to the strip f, and working in conjunction with these are spring-pressed balls g, which are connected to the sparking-plugs through the terminals g<1>. The invention is also applicable to engines working on the two-stroke cycle, in which case the bar b rotates in contact with an independent set of brushes connected to suitable resistances.