Cable-Coupled Radio Module for Metal-Housed Field Instruments
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Field devices with metal housings face challenges in electromagnetic wave propagation due to metal walls interfering with radio modules, and environmental media like water or metal-containing substances hinder wireless data transmission, making reliable and user-friendly remote data transmission difficult.
Innovation Solution
A field device with a radio module that uses field coupling through a connecting cable to transmit and receive data electromagnetically, allowing transmission through the cable sections inside and outside the housing, even in obstructive environments, using electromagnetic radiation to bypass housing materials and media interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a radio module is installed inside a metal housing, then the field device provides mechanical stability and explosion protection, but the metal housing walls prevent electromagnetic wave propagation and block radio connection
Solution Approach 1:
The patent introduces a cable feedthrough as an intermediary element that serves dual purposes: it provides a sealed opening for cable entry (maintaining explosion protection) while simultaneously acting as an antenna element for radio signal transmission. The feedthrough creates a controlled electromagnetic coupling path between the internal radio module and external space, bypassing the blocking effect of the metal housing.
Solution Approach 2:
The cable feedthrough is designed to perform multiple functions simultaneously: mechanical sealing for explosion protection, structural support for cable entry, and electromagnetic radiation element for radio communication. This multi-functionality resolves the contradiction by integrating what were previously separate components (sealing element and antenna) into a single universal element.
2Adaptability or versatility
If the field device is surrounded by media such as water, oil, or metal-containing substances, then the device operates in harsh environments, but the media significantly impede or prevent electromagnetic wave propagation
Solution Approach 1:
The patent extracts the radio signal transmission path from the problematic environment by using the cable feedthrough as an antenna that extends the electromagnetic field coupling beyond the housing. The feedthrough acts as a transmission line that guides radio signals out of the housing before they encounter the obstructive media, effectively separating the radio communication function from the harsh environmental conditions.
3Ease of operation
If a radio module is used for wireless data transmission, then operation and configuration is simplified and shutdown is avoided, but metal housings and environmental media prevent reliable data transmission
Solution Approach 1:
The cable feedthrough serves as a mediator that enables reliable data transmission by providing a controlled electromagnetic path through the housing wall. It acts as both a physical seal and an antenna element, creating a predictable transmission channel that overcomes the blocking effect of the metal housing and reduces the impact of external media interference.
4Ease of operation
If openings are designed in the housing for cable feedthrough, then data transmission is enabled, but the openings must be designed to prevent explosion spreading which increases complexity
Solution Approach 1:
The cable feedthrough is designed as a universal component that simultaneously provides mechanical sealing for explosion protection and serves as an antenna for radio communication. This integration eliminates the need for separate explosion-proof design considerations and radio antenna openings, thereby reducing overall housing design complexity while enabling both functions.
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 reliable, user-friendly, and cost-effective remote data transmission without requiring device disassembly, compatible with metal and non-metal housings, and effective in various media conditions.
Implementation Method 1
The radio module (6) is arranged and configured to transmit and/or receive a remote data transmission signal by means of a field coupling (8) with a section (9) of the connecting line (5) located inside the housing into a section (10) of the connecting line (5) located outside the housing
Data Source
Figure 1
Figure 2~4
Figure 5
AI summary
The invention relates to a field device (1, 20, 25), in particular a level, limit level, flow, pressure, or temperature measuring device, comprising a housing (3), an electrical connecting cable (5) leading into the housing (3) through a cable gland (4), and a radio module (6) for remote data transmission housed in the housing (3), wherein the radio module (6) is arranged and configured to transmit and/or receive a remote data transmission signal via field coupling (8) with a section (9) of the connecting cable (5) located in the housing (3) to a section (10) of the connecting cable (5) located outside the housing (3). The invention also relates to a method for remote data transmission using a radio module (6) housed in a housing (3) of a field device (1, 20, 25).