GB620637A - - Google Patents

Abstract

620,637. Stroboscopic apparatus. HARTRIDGE, L. Jan. 24, 1947, No. 2311. [Class 97 (i)] [Also in Groups XXVII, XXVIII and XXXVII] Apparatus for testing fuel-injection pumps and injectors comprises a neon lamp 3 located to illuminate the spray issuing from the injectors 2 and connected to an induction coil 4 in the primary of which is a make-andbreak contact 5 actuated by a cam 5<SP>1</SP> on the pump shaft and carried by a graduated ring 12 adjustable so that the lamp may be actuated at any desired angular position of the shaft 6. The ring 12 is carried by an insulated disc 11 fastened to a bushing 13 angularly adjustable inside a fixed collar 14, and the injectors 2 are mounted in transparent tubes 20 containing gauze baffles to make the spray more visible. For testing the phase angles of a multi-element pump 8, the ring 12 is rotated to adjust the contacts 5 so that the lamp 3 is energized at the instant at which injection starts from the first pump element. An adjustable stop 18 is then fixed at the zero of the scale on ring 12 and the ring readjusted to energize the lamp 3 at the beginning of injection from the second pump element, and the phase angle determined from the reading on the scale. The duration of injection of each injector is also determined from the readings when the lamp is energized first at the beginning and then at the end of injection. In a modification, the contact 5 and induction coil 4 are replaced by a fly-wheel carrying a magnet which produces a small current at each revolution in a coil carried by the ring 12, the current actuating the lamp 3 after amplification.