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. 25, 2025
Filed:
Mar. 27, 2023
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Katsumasa Uji, Tsukuba, JP;
Hitachi Construction Machinery Co., Ltd., Tokyo, JP;
Abstract
A construction machine is provided which includes a plurality of hydraulic actuators, a hydraulic pump that discharges pressurized fluid for driving the hydraulic actuators, an engine that drives the hydraulic pump, a plurality of operation lever devices that operate the corresponding hydraulic actuators, a key switch that starts the engine, a speed sensor that senses a rotational speed of the engine, a plurality of operation sensors that sense operation of the corresponding operation lever devices, and a controller that drives, in response to operation of the operation lever devices, the corresponding hydraulic actuators. The controller decides, on the basis of signals from the key switch, the speed sensor, and the plurality of operation sensors, whether operation of the operation lever device is first time operation after start of the engine, and limits, in a case where the operation of the operation lever device is first time operation after start of the engine, the action speed of the hydraulic actuator.