Resonant Inductive PCB Coil Elevator Position Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current elevator position detection systems face challenges in achieving precise and accurate positioning of elevator cars within elevator shafts, particularly in detecting small changes in position near landings.

Innovation Solution

The implementation of contactless linear position sensors based on resonant inductive PCB coils, which include a 'long' sensor with transmit and receive coils attached to the elevator car and passive cooperating tags fixed at various locations within the elevator shaft, allowing for accurate position detection without physical contact.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If traditional position sensors are used to detect elevator car position, then the system can provide basic position information, but the measurement precision is insufficient for detecting small changes in position near landings

Engineering Contradiction:
Improveposition detection precisionVSAvoidsensor system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces traditional mechanical position sensors with a resonant inductive sensing system using PCB coils. The sensor assembly includes a transmit coil and receive coils that detect position through electromagnetic induction rather than mechanical contact, achieving high-resolution position detection without mechanical wear or contact interference.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent utilizes changes in resonant frequency and inductive coupling parameters as the elevator car moves through the shaft. By monitoring the resonant response of PCB coils at different positions relative to landings, the system detects small position changes through parameter variations in the electromagnetic field rather than direct mechanical measurement.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If contactless linear position sensors are implemented, then high-resolution position measurement is achieved, but the device complexity increases due to multiple coils and tags

Engineering Contradiction:
Improveposition measurement resolutionVSAvoidsensor assembly complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The sensor assembly performs multiple functions: the transmit coil generates the electromagnetic field, the receive coils detect position through inductive coupling, and the same assembly can identify specific landings through unique tag configurations. This multi-functionality reduces the need for separate systems while maintaining high measurement precision.

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

Solution Approach 2:

The patent uses passive cooperating tags at landings that contain encoded position information. These tags are detected by the sensor assembly, allowing the system to identify specific landings and verify position without requiring complex active sensors at each landing location. The tags serve as simplified copies or representations of landing positions.

Inventive Principle:
Principle #26Copying

3Measurement precision

If resonant inductive PCB coils are used for position detection, then direct high-resolution measurement is enabled, but the system requires precise calibration and installation

Engineering Contradiction:
Improvemotion state measurement accuracyVSAvoidinstallation and calibration ease
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The resonant inductive sensor system automatically calibrates itself by detecting the resonant frequency and coupling characteristics of the PCB coils during operation. The system uses the inherent electromagnetic properties of the coils and tags to establish baseline measurements, reducing the need for manual calibration procedures while maintaining high measurement accuracy.

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

This solution enables direct, high-resolution measurement of the elevator car's motion state and landing position, providing redundancy, extended stroke, and unique identification of landings, thereby improving the accuracy and reliability of elevator positioning and leveling operations.

Implementation Method 1

contactless linear position sensors based on resonant inductive PCB coils, which include a 'long' sensor with transmit and receive coils

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

resonant inductive PCB coils, which include a 'long' sensor with transmit and receive coils

Methodology Applied
Scientific EffectResonance: Resonance

Data Source

PatentEP3450370B1Elevator position detection systems
Publication Date: 2025.06.04 OTIS ELEVATOR CO
  • EP3450370B1 patent drawingFigure 1
  • EP3450370B1 patent drawingFigure 2~3
  • EP3450370B1 patent drawingFigure 4A~4B

AI summary

Elevator systems (101, 300) having an elevator machine connected to an elevator car (103, 304, 402) within an elevator shaft (117, 322), the elevator shaft (117, 322) including a plurality of landings (125), at least one first sensor assembly (1011, 316, 318, 403, 411, 503, 511, 603, 611, 703, 803, 811B, 811C, 811, 911) attached to the elevator car (103, 304, 402), at least one second sensor assembly (1011, 316, 318, 403, 411, 503, 511, 603, 611, 703, 803, 811B, 811C, 811, 911) arranged within the elevator shaft (117, 322) and configured to interact with the at least one first sensor assembly (1011, 316, 318, 403, 411, 503, 511, 603, 611, 703, 803, 811B, 811C, 811, 911), and a computing system (200) in communication with at least one of the at least one first sensor assemblies (316, 711A, 711, 811A, 811) and the at least one second sensor assemblies (316, 711A, 711, 811A, 811) such that the computing system (200) receives at least one of signals or data (206) from the at least one of the at least one first sensor assemblies (316, 711A, 711, 811A, 811) and the at least one second sensor assemblies (316, 711A, 711, 811A, 811). The at least one first sensor assemblies (316, 711A, 711, 811A, 811) and the at least one second sensor assemblies (316, 711A, 711, 811A, 811) form a contactless position sensing system for determining a position of the elevator car (103, 304, 402) within the elevator shaft (117, 322).