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:
Aug. 10, 1999
Filed:
Dec. 20, 1996
Shigetoshi Konno, Tsuchiura, JP;
Toichi Hirata, Ushiku, JP;
Genroku Sugiyama, Miko-mura, JP;
Shigehiro Yoshinaga, Yokohama, JP;
Youichi Kowatari, Dejima-mura, JP;
Kouji Ishikawa, Tsuchiura, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
An engine torque, which corresponds to a target engine speed inputted in a controller, is determined by a functional computing function unit. A torque correction value is added to the engine torque, followed by the multiplication with a constant. The product is divided by a pump delivery pressure to determine a pump displacement. A target tilting corresponding to this value is determined by another functional computing function unit, and is then compared with another target tilting which has been determined from a negative control pressure. The smaller one is selected and is outputted as a target tilting. The torque correction value is set at an EEPROM through an input device as desired. Selection of a negative value as the torque correction value makes it possible to prevent occurrence of stalling.