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. 18, 1997
Filed:
Aug. 09, 1995
Lester L Peters, Columbus, IN (US);
Julius P Perr, Columbus, IN (US);
Yul J Tarr, Columbus, IN (US);
Cummins Engine Company, Inc., Columbus, IN (US);
Abstract
A cam operated open nozzle fuel injector is provided comprising a reciprocating plunger assembly including an outer plunger, an inner plunger and a variable volume timing chamber located between the plungers. A hold down force generating means includes a cam having a hold down cam or ramp portion for maintaining the inner plunger in an innermost position against the inner end of the injector body with a sufficient hold down force during each hold down period throughout injector operation independently of injector train wear. The hold down cam portion operates to move the outer plunger inwardly towards the inner plunger throughout a substantial portion of the hold down period. The hold down cam portion functions to compensate for fuel drainage from the timing chamber so as to maintain a predetermined pressure in the timing chamber corresponding to a desired hold down force. The hold down force generating device is capable of maintaining timing fluid in the timing chamber throughout the hold down period and may include a timing chamber drain regulating valve for controlling the drainage of fluid from the timing chamber.