Electronic unit injector shuttle valve

A control valve for an electronic fuel injector that selectively controls an amount of fuel supplied to the electronic fuel injector, the control valve comprising:

• a fuel injector body including a valve bore extending through at least a portion of the fuel injector body;
• an actuator selectably controllable to actuate the control valve to deliver the amount of fuel to the fuel injector;
• a bushing inserted into the valve bore;
• a shuttle valve slidingly engaged with the bushing and the shuttle valve operably coupled to an armature of the actuator such that actuation of the actuator causes an axial movement of the shuttle valve with respect to the bushing, the shuttle valve including:
• a shuttle valve top end including an armature attachment portion to operably couple the shuttle valve to the armature;
• a shuttle valve bottom end opposite the shuttle valve top end, the shuttle valve bottom end defining a sealing portion of the control valve including a shuttle valve terminal end surface and an annular sealing surface of the shuttle valve;
• a valve guide portion axially extending along a portion of the shuttle valve between the shuttle valve top tip and the shuttle valve bottom tip;
• an engagement surface portion defined along the valve guide portion, the engagement surface portion configured to slidably engage with the bushing inserted within the valve bore;
• a neck portion disposed between the shuttle valve bottom tip and a first end of the valve guide portion, the neck portion having a diameter that is smaller than a diameter of the sealing portion of the control valve and smaller than a diameter of a second end of the valve guide portion, and the neck portion defining a valve chamber between the bushing and the neck portion;
• and
• a non-engagement surface portion defined along the valve guide portion, wherein the non-engagement surface portion is a non-continuous surface circumferentially defined around the valve guide portion, wherein:
• the engagement surface portion comprises a first engagement surface length extending axially and a second engagement length surface extending axially that is less than the first axial length, the non-engagement portion is interspersed with the engagement surface portion along at least part of the first engagement surface length;
• the first engagement surface length extends from an engagement surface end at the second end to the first end of the valve guide portion;
• the second engagement surface length extends from the engagement surface end to the non-engagement surface portion;
• and
• the second engagement surface length is equal to an axial length of the non-engagement surface portion subtracted from the first engagement surface length.

An internal combustion engine including a fuel system configured to deliver a fuel supply to a plurality of engine cylinders, the internal combustion engine comprising:

• a plurality of electronic fuel injectors, each electronic fuel injector of the plurality of electronic fuel injectors including an injector body fluidly coupled to the fuel system and each engine cylinder of the plurality of cylinders;
• and
• a control valve integrated with the injector body of each electronic fuel injector of the plurality of electronic fuel injectors to selectively control the fuel supply delivered to the plurality of engine cylinders, the control valve including:
• a valve bore extending through at least a portion of the fuel injector body;
• a bushing inserted into the valve bore;
• a shuttle valve extending axially through the valve bore and slidingly engaged with the bushing;
• an actuator selectably controllable to actuate the control valve to deliver the fuel supply to each electronic fuel injector of the plurality of fuel injectors;
• an actuator armature operably coupled to a shuttle valve top end such that actuation of the actuator causes an axial movement of the shuttle valve with respect to the bushing;
• an annular sealing surface defined at a shuttle valve bottom end opposite the shuttle valve top end, and the shuttle valve bottom end defining a sealing portion of the shuttle valve including a shuttle valve terminal end surface and the annular sealing surface;
• a valve guide portion axially extending along a portion of the shuttle valve between the shuttle valve top end and the shuttle valve bottom end;
• an engagement surface portion defined along the valve guide portion, the engagement surface portion configured to slidably engage with the bushing inserted within the valve bore;
• a neck portion disposed between the shuttle valve bottom end and a first end of the valve guide portion, the neck portion having a diameter that is smaller than a diameter of the sealing portion of the control valve and smaller than a diameter of a second end of the valve guide portion, and the neck portion defining a valve chamber between the bushing and the neck portion;
• and
• a non-engagement surface portion defined along the valve guide portion, wherein the non-engagement surface portion is a non-continuous surface circumferentially defined around the valve guide portion, wherein:
• the engagement surface portion comprises a first engagement surface length extending axially and a second engagement surface length that is less than the first engagement surface length, the non-engagement portion is interspersed between at least part of the first engagement surface length;
• the first axial length extends from the second end to an intermediate engagement surface portion;
• the second engagement surface length extends from the engagement surface end of the valve guide portion to a first end of the valve guide portion;
• and
• the second engagement surface length is equal to an axial length of the non-engagement surface portion subtracted from the first engagement surface length.