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:
Sep. 30, 1997
Filed:
Apr. 26, 1996
Yoshihiro Tsuzuki, Handa, JP;
Nipon Soken, Inc., Nishio, JP;
Abstract
A fuel injection device includes an injection hole for injecting fuel therethrough, a needle movable between a first position to open the injection hole and a second position to close the injection hole, and a back-pressure chamber. The fuel injection device further includes a two-way solenoid valve for opening and closing a flow passage between the back-pressure chamber and a drain side so as to change a pressure in the back-pressure chamber. The needle is movable between the first and second positions depending on the pressure in the back-pressure chamber. A first flow restrictor and a second flow restrictor are provided in a flow passage, which introduces high-pressure fuel into the back-pressure chamber, so as to restrict a flow of the high-pressure fuel passing therethrough. The first and second flow restrictors may be arranged in series to each other. In this case, one of the first and second flow restrictors works as a flow restrictor to restrict the fuel flow passing therethrough only when the needle moves to the first position. The first and second flow restrictors may also be arranged in parallel with each other. In this case, one of the first and second flow restrictors is closed when the needle moves to the first position. In this fashion, the wasteful release of the high-pressure fuel toward the drain side during the fuel injection is effectively prevented while ensuring a quick response for stopping the fuel injection.