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:
Dec. 05, 1995
Filed:
Dec. 20, 1993
Bernhard Radermacher, Viersen, DE;
Pierburg GmbH, Neuss, DE;
Abstract
An improvement in a fuel pump for an internal combustion engine in which the fuel pump comprises an electric motor over which fuel is pumped to cool the motor, and a pump mechanism, constituted as a side-channel pump driven by the electric motor, pumps the fuel. The pump mechanism has a pump impeller provided with two opposite radial surfaces each provided with an annular ring of blades respectively cooperating with side channels provided in a pump wall to constitute first and second pump stages. A connecting channel connects an inlet region of the side channel of the second pump stage with a discharge region of the side channel of the first pump stage in an arrangement to substantially eliminate torsional moments acting on the impeller during a fuel pumping operation. A first flat region is formed on the radial surface of the pump impeller in the first pump stage and a second flat region is formed on the radial surface of the pump impeller in the second pump stage. The pressure of the fluid discharged from the second pump stage is applied to the first flat region, and the pressure of the fluid discharged from the first pump stage is applied to the second flat region so that a net axial force applied to the first and second flat regions of the pump impeller by the respective pressures of the fluid in the first and second stages substantially counterbalances a force produced on the pump impeller by the pressure of the discharged fluid acting in the direction of the first pump stage.