Elevator Rope Damage Detection via Electrical Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional methods for monitoring the condition of belt-shaped elevator ropes, particularly those with fiber-reinforced composite materials, are limited in detecting local damage and cannot automatically locate damage sites, leading to potential weakening of the rope and increased elevator downtime.

Innovation Solution

A method involving the monitoring of lateral positions of the belt-shaped rope as it passes through a crowned rope wheel, using detectors to gather and analyze data for deviations indicating damage, and triggering actions such as alarms or repairs based on detected anomalies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If visual detection of wire breaks is used for steel wire ropes, then simple inspection is possible, but it cannot be effectively utilized with belt-shaped ropes and cannot detect local damage

Engineering Contradiction:

Improveinspection simplicityVSAvoidapplicability to different rope types

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent replaces visual inspection (mechanical/optical system) with electrical resistance measurement. The load bearing members are made electrically conductive, allowing damage detection through electrical measurements rather than visual examination. This enables detection of local damage and applies to belt-shaped ropes that cannot be visually inspected.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If electrical resistance monitoring is used to detect rope damage, then condition monitoring is simple and cost effective, but it has limited detection range (350m) and cannot automatically locate damage sites

Engineering Contradiction:

Improvemonitoring system simplicityVSAvoiddamage location information

Core Design Contradiction:

Device complexityVSLoss of information

Solution Approach 1:

The patent divides the rope into multiple sections with individually addressable conductive load bearing members. By measuring resistance at different sections and comparing baseline values, the system can locate damage sites automatically along the entire rope length, overcoming the 350m detection limit while maintaining system simplicity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system continuously monitors electrical resistance and provides feedback when deviations from baseline values are detected. This feedback mechanism enables automatic damage location by identifying which specific section shows resistance changes, eliminating the need for manual searching.

Inventive Principle:

Principle #23Feedback

3Reliability

If manual searching is used to locate damaged areas in long elevator ropes, then damage can be found, but it is time-consuming and increases elevator downtime

Engineering Contradiction:

Improvedamage detection capabilityVSAvoidelevator downtime

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent replaces manual mechanical searching with automated electrical measurement. The conductive load bearing members allow the system to electrically locate damage along the entire rope length without manual intervention, dramatically reducing the time required while maintaining reliable damage detection.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

4Strength

If fiber-reinforced composite materials are used in load bearing members, then rope performance is improved, but adhesion failures and delamination are difficult to detect

Engineering Contradiction:

Improverope load bearing capacityVSAvoiddamage detection difficulty

Core Design Contradiction:

StrengthVSDifficulty of detecting and measuring

Solution Approach 1:

The patent uses electrical resistance measurement to detect adhesion failures and delamination in composite materials. By making the load bearing members electrically conductive, the system can detect changes in electrical properties that indicate bonding failures between fibers and matrix, which are invisible to visual inspection and difficult to measure by other means.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS10836606B2Method, arrangement for monitoring condition of elevator rope and elevator including such arrangement

Publication Date: 2020.11.17 KONE OYJ

AI summary

A method for monitoring a condition of a belt-shaped rope of an elevator, which rope is connected with one or more elevator units of an elevator, includes monitoring lateral positions of successive rope locations, which rope locations pass during use of the elevator via a monitoring zone located in proximity of a crowned rope wheel around which the belt-shaped rope is arranged to turn; gathering lateral position data of the belt-shaped rope, which lateral position data indicates lateral positions of several successive rope locations of the rope at the monitoring zone; analyzing the lateral position data; detecting characteristics in the lateral position data indicating damaged rope; and triggering one or more predefined actions if characteristics indicating damaged rope are detected. An arrangement and an elevator, which implement the method, are also disclosed.