Elevator Brake Monitoring to Prevent Car Drift at Floor Stops

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Elevator cars may drift away from the stopping floor due to machinery brake failures or control errors, posing a safety risk to passengers.

Innovation Solution

Regularly monitor the operating condition of machinery brakes and enforce braking force to prevent elevator cars from drifting by activating brakes when the car leaves the door zone, using non-volatile memory to record drive prevention data and ensuring safe stopping distances.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If machinery brakes are monitored regularly and activated when the car leaves the door zone, then safety against drifting is improved, but device complexity increases

Engineering Contradiction:
Improvesafety against driftingVSAvoiddevice complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control unit is programmed to automatically activate the machinery brake when the elevator car leaves the door zone of the stopping floor, before a dangerous drift can occur. This preliminary automated action prevents the need for manual intervention and ensures safety without requiring additional complex monitoring hardware.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system continuously monitors the position of the elevator car relative to the door zone using sensors, and based on this feedback, the control unit automatically activates the brake when the car exits the door zone. This closed-loop feedback mechanism ensures safety while using existing components.

Inventive Principle:
Principle #23Feedback

2Object-affected harmful factors

If the elevator car is stopped by activating machinery brakes when leaving the door zone, then shearing hazard is reduced, but stopping distance may increase

Engineering Contradiction:
Improveshearing hazardVSAvoidstopping distance
Core Design Contradiction:
Object-affected harmful factorsVSLength of moving object

Solution Approach 1:

The machinery brake is activated as a preliminary protective measure when the elevator car leaves the door zone, creating a counter-force that prevents further unwanted movement. By acting early upon detection of door zone exit, the system prevents the accumulation of drift that would require longer stopping distances.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The brake activation is applied partially - only when the car leaves the door zone rather than continuously - which provides sufficient braking force to prevent shearing hazards while minimizing unnecessary energy consumption and avoiding excessive stopping distance in normal operation.

Inventive Principle:
Principle #16Partial or excessive action

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

Prevents elevator cars from drifting away from the stopping floor, reducing the risk of shearing hazards and ensuring passenger safety by maintaining a safe distance between the elevator and the floor.

Implementation Method 1

enforce braking force to prevent elevator cars from drifting by activating brakes

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP2477925B2Method and arrangement for preventing the drifting of an elevator car
Publication Date: 2026.01.14 KONE OYJ
  • EP2477925B2 patent drawingFigure 1
  • EP2477925B2 patent drawingFigure 2A~2B
  • EP2477925B2 patent drawingFigure 3

AI summary

The invention presents a method and an arrangement for preventing the drifting of an elevator car (1) away from the stopping floor (10). In the method: a) the operating condition of one or more machinery, brakes (3) of the hoisting machine (2) of the elevator is monitored regularly b) the elevator car leaving the door zone (4) of the stopping floor (10) is stopped when the door (6) of the elevator car and/or the landing door (37) is/are open by using the aforementioned one or more machinery brakes (3) of the hoisting machine c) starting of the next. run of an elevator car (1) that has left the door zone (4) of the stopping floor (10) when the door (6) of the elevator car and/or the landing door (37) is/are open is prevented, and d) information about the drive prevention is recorded in the non-volatile memory (9) of elevator control unit (8).