US Patent No. 8,444,060, Fuel injector with deterioration detection
The patent US 8,444,060is about a fuel injection apparatus with a deterioration detection device that includes a volume changing chamber, the volume of which is determined by fuel gauge 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 gauge pressure to fuel flow rate control and decreases chances of after-injection and second injection.
Uniqueness and benefits of this technology:
1. A simple device with minimum change to a fuel system for detecting injector issues;
2. Results obtained in the detection process can be further used for compensating fuel injection rate;
3. The device is able to damp fuel pressure fluctuations in a fuel injector.
The device is especially useful for detecting and compensating injector nozzle coking.