Construction Machine Boom Rotation for Expanded Working Area

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Solution Overview

Problem

Existing construction machines, such as excavators, have limited working areas due to the restricted rotation of their work mechanisms, which hinders their operational efficiency and versatility.

Innovation Solution

A construction machine equipped with a drive device that outputs torque centered on rotational axes perpendicular or parallel to the vehicle body, allowing for the rotation of booms, arms, and attachments through multiple drive devices, enabling 360-degree movement and increased operational range.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of moving object

If the boom is rotated only in one direction relative to the reference axis, then the structure is simple, but the working area is limited

Engineering Contradiction:
Improveworking areaVSAvoidstructure complexity
Core Design Contradiction:
Area of moving objectVSDevice complexity

Solution Approach 1:

The work mechanism is divided into multiple independently rotatable components: the boom rotates around a first rotational axis relative to the vehicle body, while the arm rotates around a second rotational axis relative to the boom. This segmentation allows each component to move independently, expanding the overall working area without requiring the entire mechanism to rotate as a single unit.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces multiple rotational dimensions by establishing different rotational axes. The boom rotates around a first rotational axis that is orthogonal to the reference axis, while the arm rotates around a second rotational axis that is parallel to the first rotational axis. This multi-dimensional rotation capability significantly expands the working area beyond what would be possible with single-direction rotation.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Adaptability or versatility

If multiple drive devices are added to enable multi-directional rotation, then the operational range increases, but the device complexity increases

Engineering Contradiction:
Improveoperational rangeVSAvoidnumber of drive devices
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

Each drive device is designed to perform multiple functions. The first drive device rotates the boom around the first rotational axis and can also contribute to arm rotation. The second drive device rotates the arm around the second rotational axis. This multi-functionality allows the system to achieve complex operational ranges with a relatively small number of drive devices.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent implements dynamic rotation capabilities where the rotational axes and ranges can vary during operation. The boom can rotate to both sides of the reference axis, and the arm can rotate around a parallel axis, creating dynamically adjustable operational ranges that adapt to different work requirements, thereby increasing versatility without proportionally increasing device complexity.

Inventive Principle:
Principle #15Dynamics

3Area of moving object

If the boom is allowed to rotate to both sides of the reference axis, then the working area is expanded, but the control complexity increases

Engineering Contradiction:
Improveworking areaVSAvoidcontrol complexity
Core Design Contradiction:
Area of moving objectVSDifficulty of detecting and measuring

Solution Approach 1:

The patent incorporates detection means that detect the rotational positions of the boom and arm around their respective axes. This feedback information is used by the control device to manage the multi-directional rotation, allowing the system to track and control the complex movements without excessive difficulty. The detection system provides real-time position data that simplifies the control of bidirectional rotation.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP4715122A1Construction machine, drive device for construction machine, and drive unit for construction machine
Publication Date: 2026.03.25 NABTESCO CORP
  • EP4715122A1 patent drawingFigure 1
  • EP4715122A1 patent drawingFigure 2
  • EP4715122A1 patent drawingFigure 3

AI summary

A construction machine (10, 110, 150, 170) includes: a drive device (51) outputting torque centered on a rotational axis (51J) perpendicular to a reference axis (K) extending in upper and lower directions of a travelable vehicle body (12); and a boom (61) having a first end portion (61A) coupled to the vehicle body, the boom being rotated around the rotational axis by the torque from the drive device. When viewed in a first direction parallel to the rotational axis, the boom is rotatable to both one side and other side with respect to the reference axis.