Fuel injector and check valve
AssigneeGeneral Motors Corporation
InventorsMichael B. Goetzke, Rodney J. Bormann, Richard W. Tupek
Life of this patent
Estimating the term…
Abstract
An improved high pressure fuel injector and check valve disks therefore having annularly spaced passages including holes. A preferred embodiment for EMD diesel and dual fuel engines is a unit injector with a flat circular valve disk having a plurality of equally spaced holes located in a ring closely inward of the ledge of an associated valve cage and closely outward of the orifice or delivery opening of an associated valve seat. Alternative disk and injector embodiments are contemplated.
Claims20
A check valve for use in a high pressure unit fuel injector having a member with a central fuel delivery opening to be intermittently supplied with high pressure fuel and a flat valve seat surrounding the opening, a valve cage seated against the member and including a recess adjacent the valve seat, the recess including an annular ledge facing the valve seat, the ledge being centered on and having an inner diameter substantially larger than the delivery opening, an inwardly facing annular rim surrounding the ledge, ad a delivery chamber inward of the ledge for receiving fuel delivered from the delivery opening, said check valve comprising
- a disk receivable in the recess and having
- opposite first and second flat faces alternately seatable against the valve seat and the ledge respectively,
- an outer edge receivable in opposed relation to the rim and having limited radial clearance therefrom when centered in the recess, and
- a plurality of holes through the disk between the flat faces, the holes being located wholly outward of a circle of diameter equal tot he sum of the diameter of the delivery opening at the valve seat and the radial clearance of the centered disk, and each hole being located wholly inward of the outer edge of the disk,
- said holes forming at least a portion of the total flow area of flow passages extending between the opposite faces of the disk within a diameter equal to that of the inner diameter of the ledge.
A fuel injector of the high pressure unit injection type for liquid fuels and comprising
- pump means including a plunger reciprocal in a bushing,
- supply means for supplying fuel to the bushing for high pressure pumping by the plunger,
- control means for controlling the amount of fuel pumped by the plunger,
- delivery means including a spray tip for delivering the fuel to an engine cylinder, and
- check valve means in the delivery means between the plunger ad the spray tip and preventing the reverse flow of fuel toward the plunger, the check valve means including
- a seat member having an orifice and a flat valve seat surrounding the orifice on a side toward the spray tip,
- a valve cage including a recess having a rim for receiving a flat check valve disk and supporting it in closely spaced relation to the valve seat and centered opposite the orifice, and
- a flat check valve disk movable in the recess into and out of engagement with the valve seat, the valve disk having
- opposite first and second flat faces seatable against the valve seat and the valve cage respectively,
- an outer edge engageable with the rim and having a limited radial clearance therefrom when centered in the recess, and
- a plurality of holes through the disk between the flat faces, the holes being located wholly outward of a circle of diameter equal to the sum of the diameter of the orifice at the valve seat and twice the radial clearance of the centered disk, and each hole being located wholly inward of the outer edge of the disk.
Dependencies are inferred from the claim text.