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. 17, 1998
Filed:
Jun. 12, 1996
Erkko Fontell, Vaasa, FI;
Wartsila Diesel International Ltd Oy, Helsinki, FI;
Abstract
A fuel injection valve for an internal combustion engine comprises a valve body structure including a nozzle part formed with a needle passage having at least one nozzle passage at one end, a primary control chamber spaced along the needle passage from the nozzle passage, and a secondary control chamber. The primary control cheer is connected in use to a duct for supplying fuel under pressure. The nozzle part of the valve body structure has a seating surface between the nozzle passage and the primary control chamber. A needle structure is fitted slidably in the needle passage with one end of the needle structure proximate the seating surface. The needle structure has a first control surface that is exposed to pressure of fluid in the primary control chamber, a second control surface at the end of the needle structure proximate the seating surface, and a third control surface exposed to pressure of fluid in the secondary control chamber. The three control surfaces are disposed so that force generated by fluid pressure acting on each of these surfaces has a component urging the needle structure away from the seating surface against the force of a needle return spring. A control valve has a first position in which it communicates pressure of fuel in fuel supply duct to the secondary control chamber and a second position in which it cuts off the pressure of fuel in the fuel supply duct from the secondary control chamber. When the control valve is in its first position, it is urged by the pressure of fuel in the fuel supply duct toward its second position against the force of a control valve return spring.