Patent ID: 9435309
Filing Date: 2016-09-06
CPC Classification: F02M,F16K

Claim Text:
1. An electrically operated fuel control valve assembly for a diesel engine, the valve assembly including a body, a stator, an armature in a chamber adjacent the stator, a bore including a guide portion in the body, a poppet valve in the bore including a head and a stem, an annular valve seat adjacent an end of the bore, the armature being fixed to an end of the stem remote from the head, a spring biasing the valve head away from the seat, the stem having a guide surface guided by contact with the bore guide portion for movement to seat and unseat the head on the seat, an annular zone established radially between the stem and bore and axially between the guide surface and the head, the annular zone having a radial spacing between the stem and bore substantially greater than a maximum spacing between the guide surface and guide portion, wherein the annular zone contains fuel pressurized to injection pressure when the head seals the seat, the stem guide surface being smaller in diameter than a diameter of the bore guide portion, a difference in diameters of the guide surface and the bore guide portion being different at a location proximal to the seat compared to a location distal from the seat and whereby the head can align with the seat regardless of expected eccentricities between the bore guide portion and seat and between the stem guide surface and head, and whereby fluid leakage from the annular zone to the chamber is reduced from that which would occur where the difference in diameter between the stem guide surface and the bore guide portion was constant and sufficiently large to provide adequate radial freedom of the head to adjust for expected eccentricities between the seat and bore and between the stem guide surface and head.