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:
Jan. 11, 1994
Filed:
Feb. 27, 1992
Isao Osuka, Nagoya, JP;
Toshimi Matsumura, Aichi, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A common-rail fuel injection system for an engine includes a fuel injection device for injecting high pressure fuel from a common rail into the engine. A pumping chamber is connected to the common rail. A fuel feed device serves to feed fuel to the pumping chamber. A plunger moves upward and downward in accordance with rotation of an output shaft of the engine. The plunger defines a part of the pumping chamber. A relief valve serves to selectively return fuel from the pumping chamber to a low pressure side via a fuel return passage. The relief valve is urged toward its closed position by a pressure of the fuel in the pumping chamber. A valve closing device serves to close the relief valve. A fuel pumping control device serves to drive and control the valve closing device at a given timing to close the relief valve, thereby enabling a pressure in the pumping chamber to increase in accordance with upward movement of the plunger and pumping a given amount of fuel from the pumping chamber to the common rail. An engine speed detecting device serves to detect a rotational speed of the output shaft of the engine. In cases where an engine rotational speed detected by the engine speed detecting means is equal to or higher than a predetermined reference speed, a fuel feed suspending device serves to suspend fuel feed to the pumping chamber by the fuel feed means.