Integrated Pneumatic Detector Switch for Aircraft
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pneumatic detectors used in aircrafts require separate alarm and fault switches, which can be bulky, heavy, and prone to disconnections or leaks, limiting their efficiency and increasing manufacturing costs.
Innovation Solution
An integrated switch with a single housing containing two refractory metallic diaphragms for fault and alarm conditions, where the diaphragms deform in response to pressure changes, allowing for compact, lightweight, and cost-effective detection of overheat and fault conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If separate alarm and fault switches are used, then detection functionality is provided, but device size and weight increase
Solution Approach 1:
The patent combines separate alarm and fault switches into a single integrated switch assembly. The housing contains both a fault diaphragm and an alarm diaphragm within the same structure, sharing common components such as the pressure tube connection, housing, and electrical circuitry. This merging eliminates the need for separate switch assemblies, directly reducing overall weight and size while maintaining both detection functions.
Solution Approach 2:
The integrated switch assembly serves multiple functions within a single device: it detects both fault conditions (via the fault diaphragm responding to pressure drops) and alarm conditions (via the alarm diaphragm responding to pressure increases). This multi-functionality allows one universal assembly to replace what would traditionally require separate specialized switches, reducing weight while providing comprehensive detection capability.
2Reliability
If separate alarm and fault switches are used, then detection functionality is provided, but device complexity increases
Solution Approach 1:
The patent merges separate alarm and fault switches into a single integrated assembly with common housing, pressure tube connection, and electrical circuitry. This consolidation reduces the number of separate components that need to be installed, connected, and maintained, thereby reducing system complexity despite maintaining both detection functions.
3Reliability
If separate alarm and fault switches are used, then detection functionality is provided, but manufacturing cost increases
Solution Approach 1:
The integrated switch assembly combines fault and alarm detection functions into a single manufacturable unit. This merging allows for economies of scale in manufacturing, as the common housing, pressure tube connection, and electrical components can be produced as one assembly rather than as separate units requiring individual manufacturing and subsequent assembly. This directly reduces manufacturing cost while providing both detection 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
The integrated switch reduces size, weight, and part count, enhancing reliability and manufacturing efficiency while providing efficient detection of pressure changes, reducing the risk of disconnections and leaks, and enabling simpler integration in space-constrained applications.
Implementation Method 1
Pneumatic detectors typically utilize a pressure tube that contains a gas that will expand as it is heated, thus increasing the pressure in the tube
Implementation Method 2
An alarm switch will include a deformable diaphragm that is at a normal state when the system is at a normal pressure. As the pressure rises, the diaphragm will deform and close an electrical circuit
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An integrated switch (10) to indicate pressure changes in an environment includes a housing (11) with a cavity between a first retainer portion (12) and a second retainer portion (14), a first diaphragm (20) held in the cavity (28) of the housing (11) to indicate fault conditions and a second diaphragm (22) held in the cavity (28) of the housing (11) to indicate alarm conditions.