Elevator Brake Magnet Sensor for Wear Monitoring

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing elevator braking systems fail to effectively monitor the wear of brake pads and the positioning of brake magnets, leading to potential safety hazards due to reduced or eliminated braking capacity, which can result in dangerous situations for users.

Innovation Solution

Incorporating a sensor to detect the movement or distance between the brake magnet armature and housing, allowing for monitoring of the brake stroke, wear, and brake drum heating, enabling early identification of hazardous operating states and preventing brake failure by switching off the elevator drive before a dangerous situation occurs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If brake pad wear is not monitored, then the braking device can operate continuously, but the braking capacity is reduced or eliminated leading to dangerous situations

Engineering Contradiction:
Improvebraking safetyVSAvoidbrake pad wear status
Core Design Contradiction:
ReliabilityVSLoss of information

Solution Approach 1:

The patent implements a feedback mechanism by using a sensor to continuously monitor the position of the brake magnet armature and generate signals that provide information about brake pad wear status. This feedback loop allows the system to detect when brake pads are worn and alert operators before braking capacity is compromised, thus resolving the contradiction between continuous operation and safety.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The sensor monitors the armature position in advance to detect brake pad wear before it critically reduces braking capacity. By performing preliminary detection and generating warning signals early in the wear process, the system enables proactive maintenance actions before the brake pads are completely worn out, preventing dangerous situations.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If the brake magnet armature position is not monitored, then the device structure remains simple, but the moving brake magnet part can come into contact with the fixed brake magnet part reducing braking capacity

Engineering Contradiction:
Improvebrake capacity maintenanceVSAvoidmonitoring system structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

A sensor is integrated into the brake magnet assembly to continuously monitor the armature position and provide feedback signals. This feedback mechanism detects when the armature is approaching the brake magnet housing, alerting the system before contact occurs and braking capacity is reduced. The feedback approach adds minimal complexity while significantly improving reliability.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The sensor acts as an intermediary element between the moving armature and the fixed brake magnet housing. It indirectly monitors the relative position without requiring direct mechanical contact or complex mechanical linkages, thus maintaining simplicity while enabling position detection to prevent armature-housing contact.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of information

If a sensor is added to monitor armature position, then brake conditions can be monitored in real-time, but the device complexity increases

Engineering Contradiction:
Improvebrake operating state informationVSAvoidsensor integration
Core Design Contradiction:
Loss of informationVSDevice complexity

Solution Approach 1:

The sensor is designed to perform multiple functions: monitoring armature position, detecting brake pad wear status, and providing early warning of potential failures. By consolidating these monitoring functions into a single sensor element, the patent minimizes the increase in device complexity while maximizing the information gained about brake operating conditions.

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

Solution Approach 2:

The monitoring system is designed to be self-diagnostic, where the sensor automatically detects and reports brake conditions without requiring additional manual inspection or complex external monitoring equipment. The sensor leverages the existing magnetic field and mechanical structure to provide self-service monitoring, reducing the overall system complexity despite adding the sensing capability.

Inventive Principle:
Principle #25Self-service

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 solution enhances safety by providing real-time monitoring of brake conditions, allowing for proactive intervention to prevent brake failure and ensuring user safety by detecting wear and potential failures before they become critical.

Implementation Method 1

a brake magnet releases the brake levers against the spring force

Methodology Applied
Scientific EffectMagnetic field: Magnetic Field

Implementation Method 2

brake levers with compression springs that apply a spring force

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 3

at least one sensor being provided which detects a movement or a distance between an armature of the brake magnet and a brake magnet housing

Methodology Applied
Scientific EffectProximity detection:

Data Source

PatentEP2164790B1Device and method for controlling a brake device
Publication Date: 2015.09.30 INVENTIO AG
  • EP2164790B1 patent drawingFigure 1
  • EP2164790B1 patent drawingFigure 3
  • EP2164790B1 patent drawingFigure 4~5

AI summary

In an elevator drive having a brake device, compression springs actuate brake levers, with brake linings on a brake drum creating a braking force. The more the brake linings wear off due to abrasion, the smaller the distance of the armature to the brake magnet housing becomes. If the armature is in contact with the brake magnet housing, the braking ability of the brake linings is completely voided. In order for this dangerous operational state not to occur for the users of elevators, a sensor (27) is provided, detecting the movement of the brake magnet tappet (23). A bracket (53) is attached to the brake magnet tappet (23) on one end and the distance piece (46) carrying the sensor housing (42) is arranged on the other end. A restoring lug (5) is attached to the existing mechanical indicator (41, 42). A monitor evaluates the sensor signal and turns off the elevator drive in the event of dangerous operational states via a safety circuit.