Fluid sprinkling – spraying – and diffusing – Unitary injection nozzle and pump or accumulator plunger
Reexamination Certificate
1999-12-30
2001-04-03
Morris, Lesley D. (Department: 3752)
Fluid sprinkling, spraying, and diffusing
Unitary injection nozzle and pump or accumulator plunger
C239S092000
Reexamination Certificate
active
06209798
ABSTRACT:
TECHNICAL FIELD
The present invention relates generally to tappet assemblies for fuel injectors, and more particularly to a mechanism that maintains a tappet connected to the body of a fuel injector during shipping, handling and installation.
BACKGROUND ART
One class of fuel injectors are mechanically actuated via a rocker arm assembly that moves with each rotation of an engine's cam shaft. The rocker arm moves a tappet downward, and a plunger underneath the tappet pressurizes fuel during the downward stroke. A spring retracts the plunger and tappet between injection events. The spring, which is always compressed, also maintains the tappet in contact with the rocker arm throughout the operation of the system. In most of these types of injectors, the compression spring pushes the tappet away from the injector body, but the rocker arm limits how far the tappet can be moved away from the injector body, and thus prevents the tappet from disconnecting from the injector body after installation.
During assembly, shipping and handling before the injector is installed in an engine, there is often the possibility that the tappet will accidentally disconnect from the injector body. This occurs because the tappet return spring pushes the tappet away from the injector body, and there is often no means provided for holding the tappet connected to the injector body prior to installation. In some instances, it is possible to use an external clamping mechanism to hold the tappet to the injector body prior to, and during, installation in an engine. However, in many cases space constraints during installation are so severe that no room on the outside of the assembled injector is available for retaining the tappet in the injector body. In these cases, one must either include an internal retention means or accept the risk that some tappets will become disconnected from their respective injector bodies during pre-installation shipping and handling. Oftentimes internal retention means are limited or unavailable due to internal structural and space constraints. In addition, any retention means should be either removable upon installation or arranged such that the same will not interfere with normal operation of the injector after being installed in an engine.
The present invention is directed to overcoming one or more of the problems as set forth above.
DISCLOSURE OF THE INVENTION
A fuel injector includes a tappet assembly mounted on an injector body. At least one of the tappet assembly and the injector body define a retention opening therethrough. A retention member is positioned in the retention opening and concealed by at least one of the tappet assembly and the injector body. The tappet assembly is moveable with respect to the injector body an unadjustable displacement distance between an advanced position and an extended position. The height of the retention opening is less than the unadjustable displacement distance.
REFERENCES:
patent: 3982693 (1976-09-01), Hulsing
patent: 4402456 (1983-09-01), Schneider
patent: 4485969 (1984-12-01), Deckard et al.
patent: 4505243 (1985-03-01), Miwa
patent: 4653455 (1987-03-01), Eblen et al.
patent: 5082180 (1992-01-01), Kubo et al.
patent: 5360164 (1994-11-01), Pape et al.
patent: 5370095 (1994-12-01), Yamaguchi et al.
patent: 5402764 (1995-04-01), Rossignol et al.
patent: 6029902 (2000-03-01), Hickey et al.
patent: 6032875 (2000-03-01), Grimshaw-Jones
patent: 2 113 775 (1983-01-01), None
patent: 2 240 141 (1990-12-01), None
patent: 92/10668 (1991-11-01), None
patent: 93/07385 (1993-04-01), None
Author: Unknown. Drawing of of Spring loaded means for Caterpillar 3406E Fuel Injector. Date: Publically Available Since About 1994.
Martin David E.
Ries Jeffrey R.
Streicher James J.
Caterpillar Inc.
McNeil Michael B.
Morris Lesley D.
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