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:
Aug. 20, 1991
Filed:
May. 22, 1990
Konrad Eckert, Stuttgart, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A fuel injection device of for internal combustion engines, particularly a unit fuel injector, having a pump piston preferably driven via a drive cam and having a free piston hydraulically driven by the pump piston, the free piston divides a pump chamber from a pressure chamber, from which a pressure line leads to an injection nozzle of the engine. Via a magnetic valve, the fuel to be injected is first metered into the pressure chamber during the intake stroke of the pump piston and subsequently, in the control stroke, an injection quantity determining the supply onset is metered into the pump chamber. The pump piston with spaced annular grooves serves as a reversal device. During the metering stroke, a maintenance pressure that is lower than the metering pressure of the fuel and is generated via a pressure control valve is maintained in the pump chamber.