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:
May. 11, 2010
Filed:
Mar. 20, 2008
Amy M. Hess, Metamora, IL (US);
Daniel R. Ibrahim, Metamora, IL (US);
Stephen R. Lewis, Chillicothe, IL (US);
Jayaraman Venkataraghavan, Dunlap, IL (US);
Shriprasad Lakhapati, Peoria, IL (US);
Amy M. Hess, Metamora, IL (US);
Daniel R. Ibrahim, Metamora, IL (US);
Stephen R. Lewis, Chillicothe, IL (US);
Jayaraman Venkataraghavan, Dunlap, IL (US);
Shriprasad Lakhapati, Peoria, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A fuel injector includes a piezoelectric actuator subassembly having a casing and a piezoelectric element disposed within the casing. The piezoelectric element has an operating temperature range and includes a thermally contractive material having a negative thermal expansion coefficient over a second temperature range overlapping with the operating temperature range. A preload control element is coupled with the piezoelectric element and includes a thermally expansive material having a positive thermal expansion coefficient over the second temperature range. The preload control element maintains a constant preload on the piezoelectric element over a wide temperature range to inhibit temperature induced variability in operation, and can axially lengthen in opposition to axial shortening of the piezoelectric element, responsive to a temperature increase.