Patent ID: 6959878
Filing Date: 2005-11-01
Classification: F02M

Abstract:
1. A fuel injection nozzle assembly for providing fluid communication between a fuel pump and an engine including a cylinder and a cylinder head having a socket, the nozzle assembly comprising: a unitary nozzle member having a lower portion for mounting in the socket and an upper portion for projecting above the cylinder head, the lower portion terminating in a nozzle tip for insertion into the cylinder, the nozzle member defining an axial bore and a fuel inlet orifice intersecting the axial bore, an inside surface of said axial bore adjacent said nozzle tip defining a valve seat; a fuel inlet member defining a fuel passage and having oppositely disposed inlet and outlet end portions, the outlet end portion being affixed in fluid communication with said fuel inlet orifice, the inlet end portion being mountable to the fuel pump; a cap member having upper and lower portions, the lower portion of the cap member being mounted to the upper portion of the nozzle member, the upper portion of the cap member and the upper portion of the nozzle member defining a spring chamber; a unitary valve member disposed to axially reciprocate within the axial bore of the nozzle member, the valve member having oppositely disposed nose end and head ends, the nose end being disposed adjacent said nozzle tip, and including an integral spring seat and axially extending lift stop terminating at said head end; and a spring subassembly disposed within the spring chamber, the spring subassembly including a spring disposed around the lift stop, at least one lift shim having an axial thickness (B) disposed adjacent the cap member, and an opening pressure shim disposed intermediate the lift shim and the nozzle member, the opening pressure shim defining an axial opening, the head end of the lift stop being received within an axial opening of the opening pressure shim, the spring being compressively engaged between the opening pressure shim and the spring seat, wherein said valve member reciprocates a first axial distance between a closed position in which said nose end is in close contact with said valve seat and an open position in which said head end is in contact with said lift shim, said first axial distance being adjustable by selection and mounting of said at least one lift shim from a family of lift shims having axial thicknesses (B), said valve member moving axially away from said valve seat in response to a minimum opening pressure exerted on an actuating surface of said valve member by a charge of pressurized fuel in said axial bore and said minimum opening pressure is adjustable by selection and mounting of at least one opening pressure shim having an axial thickness (D) from a family of opening pressure shims, the axial thickness (D) of said at least one opening pressure shim being at least partially dependent upon the axial thickness (B) of the at least one lift shim.