Laser Cutting Head Axis Coordination for Final Cut Precision

Solution Overview

Problem

In laser cutting machines with redundant axes, the risk of overlapping or entangling occurs between cut-out workpiece sections and remaining sheets due to the continued movement of axes after the cutting process is completed, leading to inefficiencies and increased processing time for the final cut.

Innovation Solution

Implementing a method where the coarse axis is supplied a constant target value before the cutting-out end position, allowing the workpiece to stop while the fine axis continues to move, thereby initiating a flying final cut without prior stopping of the redundant axes, using a low-pass filter and a switch to manage drive axis target values and ensure precise stopping at the end position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the coarse axis is stopped before the final cut to prevent overlapping, then the reliability is improved, but the processing time increases

Engineering Contradiction:

Improveprocess reliabilityVSAvoidprocessing time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The coarse axis is decelerated in advance before reaching the final cut position, and the fine axis is prepared to take over the cutting task. This preliminary preparation allows the transition to occur during the final cut itself, eliminating the need for additional stopping time while maintaining reliability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically transitions from coarse axis movement to fine axis movement during the final cut. The coarse axis gradually reduces speed and transfers the cutting task to the fine axis, allowing continuous operation without complete stopping, thus maintaining both reliability and efficiency.

Inventive Principle:

Principle #15Dynamics

2Productivity

If the coarse axis continues moving to maintain productivity, then the productivity is improved, but the risk of overlapping increases

Engineering Contradiction:

Improveprocessing efficiencyVSAvoidprocess reliability

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The coarse axis is decelerated in advance before reaching the final cut position, and the fine axis is prepared to take over the cutting task. This preliminary preparation allows the transition to occur during the final cut itself, eliminating the need for additional stopping time while maintaining reliability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The fine axis acts as an intermediary that takes over the cutting task from the coarse axis during the final cut. This intermediary takes over the cutting task precisely when the coarse axis is still moving, allowing continuous operation without complete stopping, thus maintaining both reliability and efficiency.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Measurement precision

If the coarse axis is decelerated early to stop at the end position, then the positioning precision is improved, but the processing time increases

Engineering Contradiction:

Improvepositioning precisionVSAvoidprocessing time

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The coarse axis is decelerated in advance before reaching the final cut position, and the fine axis is prepared to take over the cutting task. This preliminary preparation allows the transition to occur during the final cut itself, eliminating the need for additional stopping time while maintaining reliability.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The cutting action continues without interruption during the transition from coarse to fine axis. The fine axis takes over precisely when the coarse axis is still moving, maintaining continuous useful action throughout the process, thus achieving both precision and efficiency.

Inventive Principle:

Principle #20Continuity of useful action

Data Source

PatentUS10569359B2Method for cutting out a section of a workpiece using a laser beam, and an associated laser cutting machine

Publication Date: 2020.02.25 TRUMPF WERKZEUGMASCHINEN GMBH & CO KG

AI summary

This disclosure relates to methods and apparatuses for cutting out a workpiece section along a target path from a plate-shaped workpiece using a laser beam of a laser cutting machine having a first drive for moving the workpiece along a first drive axis, a second drive for moving a laser cutting head along the first drive axis. Target values of the target path of the laser beam are divided into target values for the first drive and for the second drive. Before the laser beam reaches a cutting-out end position of the workpiece section, the target values for the first drive are set to a constant value, so that after braking of the first drive, the cutting out of the workpiece section is only still executed by moving the laser cutting head and the workpiece comes to a stop at latest at the cutting-out end position.