Work machine
The controller in hydraulic excavators addresses misjudgment of solenoid valve states by using operation signal comparisons and shutoff controls, ensuring safe operation and preventing unintended actuator activation.
WO2026141582A1PCT designated stage Publication Date: 2026-07-02HITACHI CONSTRUCTION MACHINERY CO LTD
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- HITACHI CONSTRUCTION MACHINERY CO LTD
- Filing Date
- 2025-12-25
- Publication Date
- 2026-07-02
AI Technical Summary
Technical Problem
Existing hydraulic excavators face misjudgment of solenoid valve stuck states due to pressure buildup in the pilot line, leading to unintended operation of hydraulic actuators even when the operation device is not being operated.
Method used
A controller determines the abnormal open/stuck state of solenoid valves by comparing operation signals with state sensor feedback, and implements notification or shutoff controls to prevent misjudgment, using a switching valve to manage pilot pressure supply.
Benefits of technology
Prevents misjudgment of solenoid valve states, ensuring safe operation by stopping the machine when abnormal conditions are detected, and informing the operator of potential issues.
✦ Generated by Eureka AI based on patent content.
Smart Images
Figure JP2025045636_02072026_PF_FP_ABST
Abstract
A work machine according to the present invention comprises: a state sensor that detects the drive state of solenoid valves; and a controller that controls the solenoid valves on the basis of an operation signal from an operating device. The controller determines whether the solenoid valves are being operated on the basis of an operation signal from the operating device. When a prescribed one of the solenoid valves is not being operated, the controller determines whether the prescribed solenoid valve is in an open-locked abnormal state on the basis of the drive state of the prescribed solenoid valve as detected by the state sensor and the drive state, as detected by the state sensor, of one of the solenoid valves that is different from the prescribed solenoid valve. When it is determined that the prescribed solenoid valve is in the open-locked abnormal state, the controller performs at least one of the following: notification control to inform an operator of the open-locked abnormal state; and source pressure shutoff control to shut off supply of source pressure from a pilot hydraulic source to a plurality of the solenoid valves by using a shutoff valve.
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