Fuel injector including valve seat plate having stress-limiting groove
AssigneeCaterpillar Inc.
InventorCory A. Brown
Life of this patent
Estimating the term…
Abstract
A fuel injector includes an injector body and a valve stack within the injector body that includes a valve seat plate. The valve seat plate includes a pressure control passage for controlling fuel injection, and a valve seat positioned fluidly between the pressure control passage and a low-pressure drain. The valve seat plate includes a pressure-limiting annular groove that extends circumferentially around the valve seat and axially inward from a side of the valve seat plate where the valve seat is located. The groove enables deformation in response to pressure differences across the valve seat plate in a manner that limits stress concentrations.
Claims10
A valve seat plate for a fuel injector comprising:
- a disc-shaped body defining a center axis and having an outer peripheral surface extending circumferentially around the center axis and axially between a first side and a second side of the disc-shaped body;
- the disc-shaped body defining a nozzle supply passage and a pressure control passage each extending through the disc-shaped body between the first side and the second side;
- a valve seat is formed on the first side of the disc-shaped body and is fluidly connected to the pressure control passage;
- a stress-limiting groove is formed in the first side and extends circumferentially around the valve seat at a location radially outward of the valve seat and radially inward of the nozzle supply passage;
- the stress-limiting groove including a radially inward groove surface defining a first circle having a constant curvature 360 degrees around the center axis, and a radially outward groove surface defining a second circle having a constant curvature 360 degrees around the center axis;
- and
- the disc-shaped body further including an end surface upon the first side oriented normal to the center axis and extending from the stress-limiting groove to the outer peripheral surface.
A valve seat plate for a fuel injector comprising:
- a disc-shaped body defining a center axis and having an outer peripheral surface extending circumferentially around the center axis, and axially between a first side of the disc-shaped body having an axial end surface, and a second side of the disc-shaped body;
- the disc-shaped body defining a nozzle supply passage and a pressure control passage each extending through the disc-shaped body between the first side and the second side;
- a valve seat formed in the first side and fluidly connected to the pressure control passage, and the center axis extends through the valve seat;
- a first set of sealing surfaces raised relative to the axial end surface and distributed circumferentially around the valve seat at a location that is radially inward;
- a second set of sealing surfaces raised relative to the axial end surface, and distributed circumferentially around the center axis at a location that is radially outward of the first set of sealing surface and spaced radially inward of the outer peripheral surface;
- the first set of sealing surfaces and the second set of sealing surfaces each defining a flat plane, and the two flat planes being positioned coplanar within a common flat plane;
- and
- a stress-limiting groove formed in the first side and extending circumferentially around the valve seat at a location that is radially between the first set of sealing surfaces and the second set of sealing surfaces.
Dependencies are inferred from the claim text.