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. 26, 2024
Filed:
Apr. 18, 2019
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Tsutomu Udagawa, Tsukuba, JP;
Junji Yamamoto, Tsukuba, JP;
Shigeyuki Sakurai, Kasumigaura, JP;
Yukihito Suzuki, Tsukuba, JP;
Hidenobu Tsukada, Ushiku, JP;
Atsushi Kanda, Tsukuba, JP;
HITACHI CONSTRUCTION MACHINERY CO., LTD., Tokyo, JP;
Abstract
A cost required to perform the diagnosis of the degradation such as a reduction in output power of an engine while engine degradation diagnosis accuracy is improved. To this end, a controller(engine diagnosing device) determines whether a hydraulic pumpis in a preset loaded state (an operation scene where a load torque of the hydraulic pumpis in a stable state) for acquiring diagnosis data of an engine, and validates a controlled variable related to a torque command value Ta of speed sensing control as the diagnosis data of the enginewhen it is determined that the hydraulic pumpis in the present loaded state, generates time history data using this validated controlled variable as a current feature variable, and enables this time history data to be displayed as trend data for engine diagnosis on a display device