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:
May. 27, 2003
Filed:
Sep. 10, 2001
Josef Guentert, Gerlingen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A high-pressure piston pump with a plurality of pump elements is connected on the intake side to a pump that pumps fuel at low pressure in a regulated quantity. Each pump element is preceded on the intake side by a first and a second check valve in series. The first check valve opens counter to spring force in the intake phase of the pump element and closes in the pumping phase. The second check valve opens counter to spring force and closes, reinforced by spring force, at pressures of the fuel supplied by the pump that are higher than the negative pressure generated in a cylinder chamber of the pump element. The second check valve takes on the metering of the fuel supplied to the pump element; the first check valve blocks off the cylinder chamber counter to the check valve in the pumping phase, whereby the piston pump serves to supply fuel at high pressure in fuel injection systems of internal combustion engines, especially in a common rail injection system.