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:
Feb. 22, 2000
Filed:
May. 08, 1998
Lianghe Zuo, Chicago, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A hydraulically-actuated fuel injector includes an injector body that defines an actuation fluid inlet, a first actuation fluid passage, a second actuation fluid passage, a fuel inlet and a nozzle outlet. A solenoid actuated control valve is attached to the injector body and includes a spool valve member moveable between a first position and a second position. The actuation fluid inlet is closed to the first actuation fluid passage and open to the second actuation fluid passage when the spool valve member is in its first position. The actuation fluid inlet is open to the first actuation fluid passage and closed to the second actuation fluid passage when the spool valve member is in its second position. A piston is positioned in the injector body and moveable between a retracted position and an advanced position. The piston has an upper end exposed to fluid pressure in the first actuation fluid passage. A needle valve member is positioned in the injector body and moveable between an inject position in which the nozzle outlet is open, and a closed position in which the nozzle outlet is blocked. The needle valve member has a closing hydraulic surface exposed to fluid pressure in the second actuation fluid passage.