The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 20, 2005
Filed:
Jul. 19, 2004
Dana R. Coldren, Fairbury, IL (US);
Stephen R. Lewis, Chillicothe, IL (US);
Michael R. Huffman, Dunlap, IL (US);
Dana R. Coldren, Fairbury, IL (US);
Stephen R. Lewis, Chillicothe, IL (US);
Michael R. Huffman, Dunlap, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A fuel injection system includes a fuel pressurizer that may be cam actuated. The fuel injection system also includes an electronically controlled spill valve and an electronically controlled needle control valve. The energization of the electronically controlled spill valve closes a fuel pressurization chamber to a drain passage to allow fuel pressure in the fuel injector to build to injection levels. The electronically controlled needle control valve controls whether high or low fuel pressure is applied to a closing hydraulic surface associated with a direct control needle valve. The fuel injection system includes a hydraulic circuitry that allows for fuel injection to occur by either maintaining the electronically controlled needle control valve in a de-energized state, or by de-energizing the same, after fuel pressure within the fuel injector has built to injection levels. With a de-energize to inject hydraulic circuitry associated with the direct control needle valve, the fuel injection system can prevent overpressurization in the event of electrical failure in the needle control electronic circuitry. This also provides a fuel engine with a limp home capability in the case of such an electronic problem. In addition, the fuel injection system can have reduced overall power requirements that can lead to downsizing and other cost saving advantages.