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:
Nov. 17, 2015
Filed:
May. 09, 2012
Naoki Sugano, Kobe, JP;
Satoshi Maekawa, Kobe, JP;
Katsuki Yamagata, Akashi, JP;
Takaharu Michida, Akashi, JP;
Hiroo Kondo, Akashi, JP;
Naoya Kitazumi, Akashi, JP;
Naoto Hori, Akashi, JP;
Naoki Sugano, Kobe, JP;
Satoshi Maekawa, Kobe, JP;
Katsuki Yamagata, Akashi, JP;
Takaharu Michida, Akashi, JP;
Hiroo Kondo, Akashi, JP;
Naoya Kitazumi, Akashi, JP;
Naoto Hori, Akashi, JP;
KABUSHIKI KAISHA KOBE SEIKO SHO, Kobe-shi, JP;
KOBELCO CRANES CO., LTD., Tokyo, JP;
Abstract
Provided is an apparatus to lower a load, comprising a hydraulic pump, a hydraulic actuator having first and second ports, a manipulation device, a hydraulic circuit including meter-in and meter-out flow passages for the first and second ports respectively and a regeneration flow passage with a check valve, a control valve, a meter-out flow controller adjusting a meter-out flow rate according to the manipulation device, a back pressure valve, and a non-regeneration operation relief valve whose set pressure is not less than a sum of a minimum set pressure of the back pressure valve, an inlet-outlet pressure difference of the meter-out flow controller when the meter-out flow rate is maximum and a discharge flow rate of the hydraulic pump is maximum, and an actuator pressure difference for driving the hydraulic actuator with no load, and not less than a maximum set pressure of the back pressure valve.