GB625826A - Testing device for the sparking plugs of internal combustion engines - Google Patents

Abstract

625,826. Testing ignition. HONEY, A. Feb. 2, 1948, No. 20810/46. [Class 7 (iv)] The invention relates to a testing device for the sparking plugs of internal combustion engines of the kind wherein relatively moveable electrodes form a calibrated spark gap and are connected to conductors which can be applied to the poles of the sparking plug the electrodes being housed within a substantially cylindrical casing, one being fixed therein and the other moveable relatively thereto and tapered at its end, the distance apart of the electrodes being indicated on a suitable scale provided longitudinally on the casing. When the terminals b<SP>1</SP>, b2 are connected in parallel with the sparking plug to be tested, the insulated stem a<SP>1</SP> of a moving electrode a<SP>2</SP> is screwed upwardly in an insulted casing g<SP>1</SP> until the gap between the electrode a<SP>2</SP> and a fixed electrode c<SP>1</SP> is of such a length as to permit the formation of a spark. The casing g<SP>1</SP> may be made partly transparent or with an opening or transparent window to enable the spark to be seen. The insulating stem a<SP>1</SP> is provided with a peripheral mark a<SP>6</SP> which co-operates with a scale on the casing g<SP>1</SP>, that is calibrated in volts or thousanths of an inch ; an insulated screw m<SP>1</SP> enables the two electrodes a2, c<SP>1</SP> to be brought into contact in order to effect zero adjustment on the scale.