Supply Line Guide Roller Layout for Robot Strand Tension Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing guide systems for industrial robots face challenges in providing precise and stress-free guidance for supply lines due to complex movement sequences, leading to issues like snagging, tangling, and increased mechanical load on the strands, which can result in strand breakage.

Innovation Solution

A guide system with a deflection roller and a reset device that uses a controlled restoring force, generated mechanically or pneumatically, to maintain constant tension and prevent sagging, combined with sensors for real-time adjustment and emergency shutdown, and a modular design for easy adaptation to different robotic systems.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the strand is designed as a hose or link chain with a curved guide surface for deflection, then the supply lines can be guided along the robot structure, but the mechanical load on the strand increases due to partial slipping on the curved surface

Engineering Contradiction:
Improveguidance of supply linesVSAvoidmechanical load on strand
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The deflection element is designed with a curved guide surface that matches the deflection bend of the strand. This curvature allows the strand to follow a smooth path around the deflection element, reducing sharp bends and slipping that would increase mechanical load. The curved geometry is optimized to maintain constant contact and distribute forces evenly along the strand.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The deflection element acts as an intermediary component between the strand and the robot structure. It provides a controlled interface that guides the strand while minimizing direct contact with other structural elements, thereby reducing snagging and tangling risks. The deflection element mediates the interaction between the moving strand and the stationary robot framework.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Strength

If small cylindrical rollers are integrated into the molded part to reduce mechanical load, then the load is reduced insignificantly, but the construction becomes complex

Engineering Contradiction:
Improvemechanical load on strandVSAvoidconstruction complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The roller components are extracted from the molded part and implemented as separate, freely rotatable deflection elements. This separation allows the rollers to be optimized independently for reducing mechanical load through rotation, while the molded part remains relatively simple. The rotatable nature of the separated rollers provides superior load reduction compared to integrated fixed rollers.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The deflection element is designed to be freely rotatable rather than fixed, allowing it to dynamically adapt to the movement and tension of the strand. This rotational freedom enables the element to self-adjust during operation, maintaining optimal contact and reducing mechanical load through rolling motion, while keeping the overall construction simple.

Inventive Principle:
Principle #15Dynamics

3Ease of operation

If the deflection element is kept freely movable in space by the strand, then the strand can move freely, but the angle enclosed by the strands and the forces acting on the strand change due to the construction

Engineering Contradiction:
Improvemovement freedom of strandVSAvoidforces and moments on strand
Core Design Contradiction:
Ease of operationVSStability of the object's composition

Solution Approach 1:

The deflection element is pre-loaded with a restoring force that acts to return it to a neutral position. This beforehand cushioning ensures that as the strand moves and changes the enclosed angle, the restoring force continuously adjusts to maintain stable forces and moments on the strand. The pre-loaded spring provides a cushioning effect that compensates for variations in geometry during movement.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Solution Approach 2:

The restoring force mechanism provides continuous feedback to the deflection element, automatically adjusting its position to maintain optimal force distribution on the strand. As the strand movement changes the enclosed angle, the restoring force responds by adjusting the deflection element's position, thereby stabilizing the forces and moments acting on the strand throughout the range of motion.

Inventive Principle:
Principle #23Feedback

4Adaptability or versatility

If a longer compensating section is provided in the strand, then complex movement sequences can be accommodated, but the strand may sag and require forceful restoration

Engineering Contradiction:
Improvelength compensationVSAvoidsagging of strand
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The restoring force mechanism acts as a counterweight system that continuously applies a force to oppose the sagging of the compensating section. This counteracting force balances the gravitational and inertial effects on the extended strand, maintaining tension and preventing excessive sagging even when the strand is fully extended to accommodate complex movement sequences.

Inventive Principle:
Principle #8Anti-weight (Counterweight)

Solution Approach 2:

The restoring force is pre-loaded and ready to act immediately when the strand sags or extends beyond its neutral position. This beforehand cushioning ensures that the strand is continuously supported and returned to its proper tension state, preventing permanent deformation or damage from excessive sagging while maintaining the necessary length compensation capability.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The guide system ensures stable and efficient guidance of supply lines, reducing mechanical stress and the risk of breakage, while allowing for adaptive control and emergency responses to ensure continuous operation.

Implementation Method 1

DE 10 2009 037 517 A1 discloses a guidance system of the type mentioned at outset for guiding supply lines on an industrial robot with a longer compensating section, which has a linear guide and a restoring means with a torsion spring. The restoring means converts the torque of the torsion spring into a linearly acting force

Methodology Applied
Scientific EffectTorsion spring: Torsion Spring

Implementation Method 2

WO 2005/123350 A1 describes a guidance system in which a spring arranged helically around the strand is deflected into the deflected position to reset a section of the strand, which spring pulls the strand back into the reset position when the robot moves back

Methodology Applied
Scientific EffectSpring: Spring

Data Source

PatentEP3415287B1Guide system for supply lines and robot having a guide system
Publication Date: 2023.09.06 IGUS GMBH
  • EP3415287B1 patent drawingFigure 1a~2b
  • EP3415287B1 patent drawingFigure 3a~4b
  • EP3415287B1 patent drawingFigure 5a~5d

AI summary

Guide system (1) for supply lines for a handling device with a base, a strand (3) in which the supply lines can be arranged and which has two sections (6, 7) connected via a deflection bend (5), and a return device (10) for returning the strand (3) from a deflection position to a return position, wherein the return device (10) has a deflection roller (13) which is rotatably mounted perpendicular to a plane of the bend in which the deflection bend (5) is arranged and on which the deflection bend (5) rests laterally at a central angle of 180°, and a linear guide rail (21) for the deflection roller (13) in which the deflection roller (13) engages with an anchor in a sliding manner with its axis of rotation (d).