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.

Date of Patent:
Mar. 15, 2022

Filed:

Aug. 09, 2018
Applicant:

Hitachi Construction Machinery Co., Ltd., Tokyo, JP;

Inventors:

Tsutomu Udagawa, Tsukuba, JP;

Shigeyuki Sakurai, Tsukuba, JP;

Yukihito Suzuki, Tsukuba, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E02F 9/22 (2006.01); E02F 9/26 (2006.01); F15B 21/00 (2006.01); F15B 11/17 (2006.01); F15B 19/00 (2006.01); E02F 9/02 (2006.01); E02F 9/20 (2006.01); F04B 49/00 (2006.01); B62D 11/00 (2006.01); E02F 3/32 (2006.01);
U.S. Cl.
CPC ...
E02F 9/2235 (2013.01); B62D 11/005 (2013.01); E02F 9/02 (2013.01); E02F 9/2004 (2013.01); E02F 9/2271 (2013.01); E02F 9/2292 (2013.01); E02F 9/2296 (2013.01); E02F 9/26 (2013.01); E02F 9/267 (2013.01); F04B 49/007 (2013.01); F15B 11/17 (2013.01); F15B 19/005 (2013.01); F15B 21/001 (2013.01); E02F 3/32 (2013.01);
Abstract

A hydraulic work machine is provided in which left and right hydraulic motors are driven independently of each other by two hydraulic pumps and in which an anomaly of any of the left and right track devices can be detected with high accuracy. The hydraulic work machine includes a first pressure sensorconfigured to detect a first pump pressure that is a delivery pressure of a first hydraulic pumpand a second pressure sensorconfigured to detect a second pump pressure that is a delivery pressure of a second hydraulic pump. When a controllerdecides, from detection results of a travel operation detectorand work operation detectorsand, that a work implementis not operated but travel operation devicesandare operated and besides left and right track devicesandare straightly traveling, the controllercalculates an anomaly decision evaluation value based on a pressure difference value obtained by subtracting one from the other of the first pump pressure and the second pump pressure and decides, based on a result of comparison between the anomaly decision evaluation value and a predetermined decision reference value, that one of the left and right track devices has an anomaly.


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