Hydraulic Excavator Jack-Up Speed Control Near Target Surfaces

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Hydraulic excavators face challenges in quickly jacking up near a construction target surface due to slow correction of boom operating speed when the target surface and bucket are kept apart, leading to inefficiencies in operability and workability.

Innovation Solution

A hydraulic excavator system with a drive controller that determines a target jack-up speed based on the distance to the construction target surface and corrects the target operation speed to enable quick jacking up, utilizing sensors and actuators to control the working front's posture and motion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the correction amount of the boom operating speed increases with the length of time that the construction target surface and the bucket are kept apart, then the excavation accuracy is maintained, but the jack-up speed becomes slow

Engineering Contradiction:
Improveexcavation accuracyVSAvoidjack-up speed
Core Design Contradiction:
Manufacturing precisionVSSpeed

Solution Approach 1:

The control method dynamically adjusts the boom operating speed based on the detected jack-up state and distance to target surface. When jack-up is detected, the system transitions from a slow correction mode to a quick jack-up mode, making the control system adaptive to different operational phases rather than using a fixed correction approach

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system continuously monitors the distance between the bucket and target surface, detects jack-up state, and uses this feedback information to adjust the boom operating speed in real-time. This closed-loop control enables the system to respond to changing conditions and optimize both accuracy and speed

Inventive Principle:
Principle #23Feedback

2Manufacturing precision

If the hydraulic excavator jacks up slowly to maintain excavation accuracy, then the bucket does not enter the construction target surface, but the operability and workability deteriorate

Engineering Contradiction:
Improveexcavation accuracyVSAvoidoperability
Core Design Contradiction:
Manufacturing precisionVSEase of operation

Solution Approach 1:

The control system dynamically switches between different operational modes: a slow correction mode for maintaining accuracy during normal operation, and a quick jack-up mode when jack-up is detected. This dynamic adaptation resolves the conflict between accuracy and operability by providing the appropriate speed for each operational phase

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system changes the control parameter (boom operating speed) based on the operational state. When jack-up is detected, the target operation speed is increased to enable quick jack-up, while maintaining accuracy control through continuous distance monitoring and semi-automatic operation along the target surface

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4098804B1Hydraulic excavator
Publication Date: 2025.09.17 HITACHI CONSTRUCTION MACHINERY CO LTD
  • EP4098804B1 patent drawingFigure 1
  • EP4098804B1 patent drawingFigure 2
  • EP4098804B1 patent drawingFigure 3

AI summary

A hydraulic excavator 1 includes a traveling body 4, a slewing body 3, a working front 2 having a boom 20, an arm 21, and a bucket 22, an operation amount detector 33, a posture detector 38, a load detector 39, a drive controller 34, and a drive unit 35. The drive controller 34 calculates a target operation speed of the actuator based on the operation amount, the posture of the working front, and the target surface distance so that the bucket 22 excavates along the construction target surface, and determines soil hardness of a place to be excavated based on a result detected by the load detector 39, corrects the target operation speed based on the soil hardness, and generates a motion command value. The drive controller 34 determines a target jack-up speed when the hydraulic excavator jacks up based on the target surface distance, and corrects the target operation speed based on the determined target jack-up speed.