New Ideas In Ignition Equipment

Poverty Bay Herald, Volume LXIII, Issue 19124, 19 September 1936, Page 9

New Ideas In Ignition Equipment

A LARGE English manufacturer of ignition equipment has recently developed some new ideas, which in a practical test have had a rather startling effect on ear performance. 1: is fairly well known amongst motor engineers that wide sparking plug gaps are favourable to smooth idling- and pulling at ultra low speeds, provided that the throttle opening is con-i;ini; but they cannot compensate for derangement of intake conditions which occur when the throttle is opened suddenly, the absolute pressure in the inlet pipe jumping from a very low figure to a value almost atmospheric, and temporarily the supply of fuel lags behind the flow of air. Another objection to the use of wide gaps is that an excessive strain is placed upon the high tension windings of the coil.

The manufacturer in question has produced a coil of especially high quality, capable of withstanding the extra strain of wide spark plug gaps, and also, to overcome the carbiiretion difficulty, u simple device consisting of a small piston and cylinder connected through valves to the float chamber and inlet pipe. The piston is controlled by :i bellows and spring.

Rapid Pick-up. When the engine is idling, inlet pipe suction exhausts the bellows, SO allowing atmospheric pressure to compress the spring and withdraw the piston. A small charge of petrol is then drawn into the cylinder from the float chamber. When the throttle is opened suddenly tfio ;..-e iii pressure in the inlet pipe allows the spring to expand the bellows, so>operntiitg the piston and expelling the charge of petrol through a (ine orifice into the inlet pipe. When tested on a six-cylinder lilt.p. car it is said I ha!, from a smooth idling speed of :: m.p.li. in. top gear (which is very low in 'these days of high compression ratios}, a very rapid and smooth pick-up could be obtained simply by throwing the throttle wide open.' At high speeds also, response was found to be immediate. The company responsible for this development Ims a sufficiently high reputation to give it a considerable amount of importance.