Direct operated check injector
AssigneeCaterpillar Inc.
InventorsDonald John Waldman, Keith Edward Lawrence, Steven James Funke, Craig William Lohmann
Life of this patent
Estimating the term…
Abstract
A fuel injector includes an injector body and a three-way control valve having a valve element movable between first and second positions in the injector body. A check is disposed in the injector body and is movable to inject fuel when the control valve is in the second position and to block fuel injection when the control valve is in the first position. An actuator is selectively operable to move the valve element between the first and second positions. The injector includes a single clearance fit located in the control valve wherein the clearance fit is not exposed to a substantial pressure differential when the control valve is in the first position.
Claims30
A fuel injector, comprising
- an injector body assembly;
- a three-way control valve having a valve element movable between first and second positions;
- a check disposed in the injector body assembly and movable in response to fluid pressures applied to ends thereof to inject fuel into a combustion chamber when the control valve is in the second position and to block injection of fuel into the combustion chamber when the control valve is in the first position;
- and
- an actuator selectively operable to move the valve element between the first and second positions;
- the injector including a clearance fit located in the control valve and partially defined by a portion of the check, such that the clearance fit is not exposed to a substantial pressure differential when the control valve is in the first position.
A fuel injector for injecting fuel into a combustion chamber, comprising:
- an injector body;
- an elongate check disposed within the injector body and movable along a certain direction between an open position at which fuel is injected into the combustion chamber and a closed position at which fuel is not injected into the combustion chamber;
- a three-way valve including a valve element movable between a first position within a valve element chamber wherein a first sealing surface of the valve element is disposed in sealing contact with a first valve seat and a second position within the valve element chamber wherein a second sealing surface of the valve element is disposed in sealing contact with a second valve seat and wherein the valve element further includes a first bore within which a first end of the check is disposed for movement along the certain direction and a second bore in fluid communication between the valve element chamber and the first end of the check;
- an actuator coupled to the valve element for moving the valve element between the first and second positions;
- a source of low fluid pressure in fluid communication with the first sealing surface of the valve element;
- and
- a source of high fluid pressure in fluid communication with the second sealing surface of the valve element and in fluid communication with the second end of the check.
Dependencies are inferred from the claim text.