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. 31, 2002
Filed:
Jun. 01, 2001
Jingming Jim Shen, Newport News, VA (US);
Bogdan Gromek, Yorktown, VA (US);
Siemens Automotive Corporation, Auburn Hills, MI (US);
Abstract
A fuel injector comprises a body having a longitudinal axis, a piezoelectric actuator that has first and second ends, a needle coupled to the first end of the piezoelectric actuator, and a hydraulic compensator coupled the second end of the piezoelectric actuator. The piezoelectric actuator includes a plurality of piezoelectric elements along the axis between the first and second ends. The needle is movable between a first configuration permitting fuel injection and a second configuration preventing fuel injection. And the hydraulic compensator axially positions the piezoelectric actuator with respect to the body in response to temperature variation. Also, a method of compensating for thermal expansion or contraction of the fuel injector comprises providing fuel from a fuel supply to the fuel injector; and axially adjusting the piezoelectric actuator with respect to the body in response to temperature variation. The axially adjusting includes moving hydraulic oil through an orifice connecting first and second hydraulic oil reservoirs.