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:
Feb. 26, 2019
Filed:
Nov. 26, 2014
Hitachi Construction Machinery Tierra Co., Ltd., Kobe-shi, Shiga, JP;
Kiwamu Takahashi, Moriyama, JP;
Yasutaka Tsuruga, Ryuugasaki, JP;
Yoshifumi Takebayashi, Kouka, JP;
Kazushige Mori, Moriyama, JP;
Natsuki Nakamura, Kouka, JP;
Yasuharu Okazaki, Namerikawa, JP;
Hiroyuki Nobezawa, Takaoka, JP;
Kenji Yamada, Toyama, JP;
Hitachi Construction Machinery Tierra Co., Ltd., Koka-shi, JP;
Abstract
To make it possible to efficiently utilize rated output torque of a prime mover by performing total torque control with high precision through precise detection of absorption torque of another hydraulic pump by use of a purely hydraulic structure and feedback of the absorption torque to the side of one hydraulic pump, delivery pressure of a main pump and a load sensing drive pressure are supplied to a torque feedback circuit, which modifies the delivery pressure of the main pump to achieve a characteristic simulating the absorption torque of the main pump, and outputs the modified pressure. An output pressure of the torque feedback circuit is supplied to a torque feedback piston, which controls displacement of the main pump so as to decrease the displacement of the main pump and thereby decrease maximum torque as the output pressure increases.