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. 02, 1993
Filed:
Aug. 21, 1991
James J Grinsteiner, Union, IL (US);
David B Meisner, Carol Stream, IL (US);
Navistar International Transportation Corp., Chicago, IL (US);
Abstract
A tandem fuel pump assembly for internal combustion engines includes a housing having a fixed spring retainer mounted thereinside which supports a diaphragm pump biassing spring thereabove to force a diaphragm defining the movable lower wall of a first pumping chamber to reduce the volume thereof and eject fuel from an outlet thereof preferably through a fuel filter to the inlet of a second piston pumping chamber. A second biassing spring supported below the spring retainer forces a pumping piston downwardly to reduce the volume of the second pumping chamber and thereby eject fuel therefrom to an engine fuel rail for injection into the engine therefrom. The diaphragm and piston are mechanically connected by a pump stem through a lost motion connection to accommodate differing pumping strokes of the two pumps, so that a single tappet actuated by the engine camshaft mechanically raises the piston to cause movement thereof to fill the second piston pump chamber while the biassing spring of the piston pump pulls the diaphragm through the stem against the action of its biasing spring to fill the first chamber during the pumping stroke of the piston pump.