Smoke Detector SMD Diode Modular PCB Assembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing smoke detectors based on Tyndall's effect face high production costs and complex maintenance due to manual operations, dependency on operator skill, and time-consuming replacement processes, especially when using traditional THT diodes and expensive SMD components.

Innovation Solution

The use of SMD type emitter and receiver diodes mounted on dedicated printed circuit boards, which are crosswise connected to a main printed circuit board, eliminating the need for spacers and allowing for easy replacement, along with a ground plane for interference protection, reducing manual tasks and costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If traditional THT diodes with spacers are used, then diode positioning is easy, but production cost and manual operations increase

Engineering Contradiction:
Improvediode positioningVSAvoidproduction cost
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The detector is divided into modular components: a detection chamber module containing the diodes and spacers, and a printed circuit board module. This segmentation allows the diodes to be pre-positioned on spacers within the chamber module, eliminating the need for complex manual positioning during final assembly while reducing overall production cost.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The spacers are pre-formed with positioning features (such as recesses or protrusions) that guide diode placement before the diodes are installed. This preliminary preparation of positioning structures eliminates the need for manual adjustment during assembly, reducing both labor cost and complexity.

Inventive Principle:
Principle #10Preliminary action

2Manufacturing precision

If manual welding and positioning operations are used, then assembly precision can be achieved, but production time increases

Engineering Contradiction:
Improveassembly precisionVSAvoidproduction time
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

By segmenting the assembly into pre-formed spacer-diode units, the precision positioning is achieved during the spacer manufacturing stage rather than during final assembly. This allows automated or jig-assisted formation of the spacer-diode interface, ensuring precision while reducing the time required at the assembly stage.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Manual welding operations are replaced by mechanical insertion and retention mechanisms. The diodes are mechanically retained by the spacers (through friction fit, snap-fit, or similar mechanisms), eliminating the need for time-consuming welding operations while maintaining secure positioning and assembly precision.

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

3Reliability

If diodes are welded to printed circuit board, then electrical connection is secure, but maintenance and replacement become difficult

Engineering Contradiction:
Improveelectrical connectionVSAvoiddiode replacement
Core Design Contradiction:
ReliabilityVSEase of repair

Solution Approach 1:

The detection chamber is designed as a removable module that can be detached from the printed circuit board without damaging electrical connections. The diodes remain electrically connected to the PCB through conductive elements on the chamber or through flexible printed circuit interconnects, allowing the entire chamber module to be replaced as a unit for maintenance while preserving reliable electrical connectivity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The connection between the detection chamber and printed circuit board is made dynamic rather than permanent. The chamber can be easily attached and detached, allowing for quick replacement during maintenance while maintaining secure electrical connections during operation. This dynamic connection enables tool-free or minimal-tool replacement of the diode-containing chamber.

Inventive Principle:
Principle #15Dynamics

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 reduces production times, simplifies maintenance, and decreases costs by enabling easy replacement of diodes and eliminating the need for manual welding and expensive architectures, while improving detector efficiency and reducing sensitivity dependence on assembler skill.

Implementation Method 1

emitter diode (56), and a receiver diode (55)... the respective reception and emission fields intersecting within the chamber

Methodology Applied
Scientific EffectLight emitting diode effect: Light Emitting Diode

Implementation Method 2

optical smoke detectors of the optical type based on Tyndall's effect

Methodology Applied
Scientific EffectTyndall effect: Tyndall Effect

Data Source

PatentEP1903524B1Smoke detector
Publication Date: 2009.11.04 ELKRON
  • EP1903524B1 patent drawingFigure 1
  • EP1903524B1 patent drawingFigure 2
  • EP1903524B1 patent drawingFigure 3

AI summary

The invention relates to a smoke detector comprising a detection chamber in which are positioned an emitter device which emits electromagnetic radiation (typically infrared type) and a receiver device which receives it. The smoke detector also comprises a main printed circuit board electrically connected to both the emitter device and the receiver device. The receiver device and/or the emitter device are located on dedicated printed circuit boards which are electrically connected, possibly through connectors, to the main printed circuit board.