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. 15, 1998
Filed:
Nov. 24, 1997
Kenichi Kubo, Higashimatsuyama, JP;
Mitsunori Urano, Higashimatsuyama, JP;
Toru Yokota, Higashimatsuyama, JP;
Jun Matsubara, Higashimatsuyama, JP;
Zexel Corporation, Tokyo, JP;
Abstract
In an inner-cam system fuel injection pump, two balance ports that are offset symmetrically relative to a distribution port in a circumferential direction to form a Y-shape are formed at a rotor. The opening ends of the balance ports and the opening end of the distribution port are positioned on the same plane that is perpendicular to the axis of the rotor. The offset angle .theta. by which the balance ports are offset in the circumferential direction relative to the axis of the distribution port, the opening area S.sub.1 of the distribution port and the opening area S.sub.2 of each of the balance ports are set to satisfy a relationship expressed as S.sub.1 =.vertline.2.multidot.S.sub.2 .multidot.cos .theta..vertline.. The phase intervals of the fuel delivery passages and the phase interval of the two balance ports are set equal to each other. Seizure at the area where the rotor slides in contact with its supporting member is prevented effectively and stable injection characteristics are achieved by equalizing the residual pressures in the individual fuel delivery passages.