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. 23, 1999
Filed:
Jun. 20, 1997
Kenji Hiraku, Niihari-gun, JP;
Tadahiko Nogami, Mito, JP;
Kenji Okuna, Niihari-gun, JP;
Kiyoshi Amou, Niihari-gun, JP;
Atsuji Saito, Hitachinaka, JP;
Atsuo Kishi, Hitachinaka, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A fuel feeding apparatus includes a pressure increasing piston system, in addition to a high pressure fuel pump, for further increasing the fuel pressure at the outlet of the high pressure fuel pump. For this purpose, a first piston provided in a first cylinder is moved in response to the pressure of fuel drawn up from a fuel tank and fed to the high pressure pump by a low pressure fuel feed pump, and a second piston provided in a second cylinder and having a diameter smaller than the diameter of the first piston is connected to the first piston and is moved together with the first piston for pressurizing fuel in the second cylinder communicating with the outlet of the high pressure fuel pump at the time of engine starting, and before the high pressure fuel pump is started. The first and second pistons then are automatically returned to their initial positions, respectively, after high pressure fuel pump is started, while the pressure of the highly pressurized fuel in the high pressure fuel pipe is maintained by a high pressure regulator, by designing the first and second cylinders, including the relative sizes of the respective pistons, so that a possible maximum pressure to which the fuel is increased by the piston system is set to a value lower than a preset high pressure value to be attained by the high pressure fuel pump.