Laser Cutting Bridge Profile for Stiffness and Bellows Protection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional laser cutting machines with rectangular box-shaped bridges suffer from low stiffness-to-weight ratio, unfavorable center of gravity, and susceptibility to damage from laser reflections and hot material splashes due to the parallelogram effect and placement of bellows in the processing zone.

Innovation Solution

A laser cutting machine with a bridge designed to have at least two side surfaces forming an angle with the vertical symmetry surface, creating a trapezoidal or triangular shape that widens towards the processing area, and featuring an inclined section to protect cables and bellows from material splashes, with a triangular edge top and hollow profile for improved mechanical and vibration properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a rectangular box-shaped profile is used for the bridge, then the structure is simple to manufacture, but the stiffness-to-weight ratio is low and the parallelogram effect occurs

Engineering Contradiction:
Improveease of manufactureVSAvoidstiffness-to-weight ratio
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent applies asymmetry by changing the bridge profile from a symmetric rectangular shape to an asymmetric triangular shape. The triangular cross-section with one side parallel to the horizontal and the other two sides inclined eliminates the parallelogram effect and significantly improves the stiffness-to-weight ratio while maintaining manufacturability through standard fabrication processes

Inventive Principle:
Principle #4Asymmetry

2Productivity

If the bridge is made lighter to reduce inertia, then the productivity improves, but the mechanical stability and stiffness decrease

Engineering Contradiction:
ImproveproductivityVSAvoidmechanical stability
Core Design Contradiction:
ProductivityVSStability of the object's composition

Solution Approach 1:

The patent employs composite construction by combining multiple bar elements with triangular cross-sections to form the bridge structure. This composite approach allows optimization of the overall stiffness-to-weight ratio, enabling lighter construction that maintains high mechanical stability through the geometric arrangement and material selection of the composite structure

Inventive Principle:
Principle #40Composite materials

3Device complexity

If bellows are placed on the side of the cutting head for compact design, then the device complexity is reduced, but they become vulnerable to laser reflections and hot material splashes

Engineering Contradiction:
Improvedevice complexityVSAvoiddamage from laser reflections and material splashes
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent extracts the bellows from the vulnerable processing zone by positioning them on the top surface of the bridge rather than on the side near the cutting head. This spatial separation removes the bellows from the harmful environment of laser reflections and hot material splashes while maintaining the compact overall design of the system

Inventive Principle:
Principle #2Taking out (Extraction)

4Device complexity

If the center of gravity of the cutting carriage is outside the power transmission points, then the structure is simpler, but unfavorable force distribution occurs

Engineering Contradiction:
Improvestructural simplicityVSAvoidforce distribution
Core Design Contradiction:
Device complexityVSForce

Solution Approach 1:

The asymmetric triangular profile design inherently optimizes the center of gravity position relative to the power transmission points. The geometric configuration of the triangular cross-section naturally positions the center of gravity to achieve favorable force distribution and minimize the parallelogram effect during bridge movement, eliminating the need for complex counterbalancing mechanisms

Inventive Principle:
Principle #4Asymmetry

Data Source

PatentEP3223996B1Laser cutting machine
Publication Date: 2022.09.21 BYSTRONIC LASER AG
  • EP3223996B1 patent drawingFigure 1
  • EP3223996B1 patent drawingFigure 2

AI summary

The invention relates to a bridge (B) for laser cutting machines. In the latter, a laser cutting head (K) is guided over a workpiece support (W) by means of a guide system. The bridge (B) is configured in the form of a substantially straight and box-like profile (1) which has at least one guide for a cutting carriage carrying the laser cutting head (K). According to the invention, at least two side faces (10, 11) of the profile (1) that are located opposite one another with regard to the vertical plane of symmetry (VSE) of the bridge enclose a non-zero angle (a) of less than 180° that opens in the direction of the machining region, at least over a part of the height of said profile (1).