GB1243034A - Fuel injection valve - Google Patents

Abstract

1,243,034. 243, 034. Fuel injectors. CATERPILLAR TRACTOR CO. Nov.4, 1968 [Nov. 6, 1967], No.52082/68. Heading F1B. In a fuel injection valve for an I. C. engine, fuel from a line 16 is delivered between valve case 12 and sleeve 26 to a valve chamber 52 via passages 30, 32, annular groove 34, longitudinal blind grooves 36, the clearance between the sleeve 26 and the surrounding case 12, and reversed longitudinal blind grooves 40. The clearance forms a filtering passageway for the fuel. A predetermined fuel pressure in the chamber 52 opens a valve 56 against the action of a spring 66 until an enlarged valve stem portion 60 abuts a stop 48, to allow fuel to flow through orifices 24 to the engine combustion chamber. The coils of spring 66 may be arranged to abut one another at the required degree of valve opening, thereby eliminating the need for the stop 48. The stem portion 60 is slidingly received in a mounting collar 62 having a spherical surface 68 sealingly co-operating with a conical surface 70 on the sleeve 26. During opening of the valve some fuel leaks between the stem portion 60 and collar 62 into a chamber 28. The leakage returns to the chamber 52 when the pressure therein falls to a relatively low value. The sleeve 26 may be secured in the case 12 by welding or press-fitting, or it may be screwed therein to provide adjustability of the compression of the spring 66. Injector tip 20 may be integral with the case 12 or swaged thereto. Spring retainer 64 may be integral with the valve.