Injection system with pilot-operated injector for an internal combustion engine

Abstract

Abstract A means to cut off the feeding of combustible fluid under pressure to an injector needle of a diesel engine which is stuck in the open position. The end portion of a push rod which insures the closing of the injector needle under the push of a spring includes a throat which it slides across an orifice of a predetermined cross-sectional area of value S. The orifice is in communication with a chamber wherein is mounted a differential piston. The chamber also is connected to a discharge passage by a calibrated orifice whose cross-section S is directly related to the cross-section of the orifice. At the end of each injection stroke, the throat terminates communication with the orifice of cross-section S and the pressure in the chamber is reduced before the piston is displaced. If the needle of the injector sticks in the open position, then the throat remains in communication with the orifice and the pressure in the chamber continues to increase sufficiently to overcome a preloaded spring to move the piston in the chamber which in turn is adapted to block the feeding canal 20 of the combustible fluid distribution system thereby insuring closing of the injector needle.

Inventors

• 👤 Jean-Louis Résidence Bellevue Dazzi

Bibliographic Details