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:
Mar. 24, 1998
Filed:
Feb. 19, 1997
Gregory G Hafner, Normal, IL (US);
Caterpillar Inc., Peoria, IL (US);
Abstract
A hydraulically-actuated fuel injector comprises an injector body that defines a nozzle chamber that opens to a nozzle outlet and a plunger bore, and a spill port that opens into the plunger bore. A hydraulic means within the injector body pressurizes fuel in the nozzle chamber, and includes a plunger with an end face, a side surface and a centerline. The plunger is positioned in the plunger bore and moveable a stroke distance between a retracted position and an advanced position. A needle valve member is positioned in the nozzle chamber and moveable between an open position in which the nozzle outlet is open and a closed position in which the nozzle outlet is blocked. The plunger includes a groove in its side surface that is arranged in a helical pattern about the centerline and further includes a spill passage extending between the end face and the groove. A pin and guide slot assembly, within the injector body, are provided for rotating the plunger about the centerline when the plunger is moving a portion of the stroke distance between its advanced position and its retracted position. Finally, the injector includes a control valve for stopping the plunger at a metered position between its retracted position and its advanced position when the plunger is retracting from its advanced position.