Radio Frequency Sensor for Conveyed Object Contour Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conveying devices face challenges in reliably detecting and separating consecutive objects on a conveying path due to uncontrolled object flow and the limitations of existing optical sensors, which are prone to external interference and require high installation effort.

Innovation Solution

A method using a radio frequency sensor to generate an electromagnetic field and measure the time curve of dielectric conductivity, allowing for the determination of contour information and reliable object recognition, which can be implemented in a space-saving manner below the conveying path.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If optical sensors (laser scanners, light barriers) are arranged above the conveying path to detect objects, then object detection can be performed, but installation effort increases and objects may damage the installation frames

Engineering Contradiction:

Improveobject detection reliabilityVSAvoidinstallation effort

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent inverts the conventional sensor arrangement by placing the radio frequency sensor below the conveying path instead of above it. The sensor detects objects by measuring dielectric conductivity changes in the electromagnetic field from the lower side, eliminating the need for overhead installation frames and reducing installation complexity while maintaining detection reliability

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent replaces optical detection mechanisms with radio frequency electromagnetic field-based detection. Instead of using light barriers or laser scanners that require mechanical installation structures, the system uses radio frequency sensors that can be integrated into the conveying device structure itself, substituting a mechanical installation system with an electromagnetic field-based detection system

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If optical sensors are used to detect objects on the conveying path, then object separation can be monitored, but the sensors become sensitive to external light, contamination, and dust

Engineering Contradiction:

Improveobject separation monitoringVSAvoidsensitivity to external interference

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent substitutes optical sensors with radio frequency sensors that operate using electromagnetic fields in the radio frequency range. This replacement eliminates sensitivity to external light, dust, and contamination that plague optical systems, as radio frequency waves are not affected by these environmental factors, thereby improving reliability in harsh conveying environments

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the detection parameter from optical properties (light reflection, absorption) to dielectric conductivity properties. By measuring changes in dielectric conductivity of the radio frequency field caused by objects with different materials, the system achieves interference-free detection that is insensitive to external light and contamination

Inventive Principle:

Principle #35Parameter changes

3Device complexity

If radio frequency sensor is arranged below the conveying path, then installation space is reduced and objects are protected, but the sensor must detect through the conveying path structure

Engineering Contradiction:

Improveinstallation spaceVSAvoiddetection through structure

Core Design Contradiction:

Device complexityVSDifficulty of detecting and measuring

Solution Approach 1:

The patent introduces a dielectric layer as an intermediary between the radio frequency sensor and the detection zone. This dielectric layer, positioned between the sensor and the conveying path structure, facilitates electromagnetic field penetration while maintaining signal integrity, enabling effective detection through the conveying path structure from below

Inventive Principle:

Principle #24Intermediary (Mediator)

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

Enables accurate and reliable detection of consecutive objects, distinguishing them by material and position, reducing installation effort and susceptibility to external interference.

Implementation Method 1

generating an electromagnetic radio frequency field radiating into the detection zone by means of a radio frequency sensor

Methodology Applied

Scientific EffectElectromagnetic radiation: Electromagnetic Induction

Implementation Method 2

measuring a time curve of a dielectric conductivity in the detection zone by means of the radio frequency field

Methodology Applied

Scientific EffectDielectric conductivity measurement: Dielectric

Data Source

PatentUS11453559B2Sensor device for recognizing consecutive objects

Publication Date: 2022.09.27 SICK AG

AI summary

A method of recognizing consecutive objects on a conveying path in a detection zone arranged on the conveying path comprises the following steps:generating an electromagnetic radio frequency field radiating into the detection zone by way of a radio frequency sensor;measuring a time curve of a dielectric conductivity in the detection zone by using of the radio frequency field of the radio frequency sensor; anddetermining contour information of the consecutive objects from the time curve of the dielectric conductivity.