Fuel injector with deterioration detection
OwnerMi Yaninventor
Life of this patent
Estimating the term…
Abstract
A fuel injection apparatus with a deterioration detection device that includes a volume changing chamber, the volume of which is determined by fuel pressure inside the injector. After injector nozzle opens, the time for the volume changing chamber to change from an initial volume to a target volume is measured and used for calculating changes in nozzle orifice size. The value of orifice size change can be used for both diagnosing injector deterioration and compensating fuel flow rate in a feedback control. In addition to detecting injector deterioration and failures, the volume changing device also dampens effects of noise in fuel pressure to fuel flow rate control and decreases chances of after-injection and second injection.
Claims17
A fuel injection apparatus, comprising:
- an injector body casting containing a fuel passage and at least one orifice communicating with said fuel passage to discharge fuel;
- a nozzle valve element slidably disposed adjacent said injector orifices, controlling fuel flow by moving from an open position in which fuel may flow through said injector orifices, and a closed position in which fuel flow is blocked by said nozzle valve;
- and
- at least one volume changing device communicating to said fuel passage, with the volume thereof determined by the fuel pressure inside said fuel passage.
A fuel injection system comprising:
- a fuel injection apparatus, comprising an injector body casting containing a fuel passage and at least one orifice communicating with said fuel passage to discharge fuel, a nozzle valve element slidably disposed adjacent said injector orifices, controlling fuel flow by moving from an open position in which fuel may flow through said injector orifices, and a closed position in which fuel flow is blocked by said nozzle valve, and at least one volume changing device communicating to said fuel passage, with the volume thereof determined by the fuel pressure inside said fuel passage;
- a fuel pressure sensor for measuring fuel pressure inside said fuel passage;
- and
- a timer measuring the time for fuel pressure inside said fuel passage drops from an initial value to a target value after said nozzle valve opens.
A method for detecting fuel injector deterioration, comprising steps of:
- opening injector nozzle;
- measuring volume changing time as the time for the fuel volume inside said fuel injector drops from an initial value to a target value;
- and
- calculating deterioration values using said volume changing time.
Dependencies are inferred from the claim text.