Snap Fit Mounting for Vehicle Crash Sensors

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vehicle crash sensors, particularly those for side impacts, require rapid response times and secure mounting solutions to ensure timely actuation of occupant protection systems, with existing fastening methods being inefficient and prone to water ingress.

Innovation Solution

A snap fit mounting assembly for vehicle crash sensors featuring a housing with deformable retaining structures and a pressure inlet shroud, providing an interference fit and watertight seal, allowing for easy assembly and secure attachment to a mounting structure while preventing water entry into the electrical circuitry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If traditional fastening methods are used to mount crash sensors, then the mounting process is complex and time-consuming, but the assembly lacks secure attachment and is prone to water ingress

Engineering Contradiction:
Improvemounting process efficiencyVSAvoidattachment security and water protection
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The mounting assembly is divided into separate functional components: a housing containing the crash sensor, a mounting bracket with fastening elements, and a sealing structure. This segmentation allows each component to be optimized independently for its specific function while simplifying the overall assembly process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent combines multiple functions into a single integrated mounting assembly: the housing, mounting bracket, sealing elements, and electrical connections are merged into one pre-assembled unit that attaches to the vehicle structure in a single operation, eliminating separate steps for mounting and sealing.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 3:

A sealing element or gasket acts as an intermediary between the mounting assembly and the vehicle structure, providing water protection while allowing the mechanical fastening to proceed independently. This mediator ensures reliability without complicating the mounting process.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Productivity

If existing mounting structures are used for side impact sensors, then assembly is straightforward, but response time may be delayed due to mounting delays

Engineering Contradiction:
Improveassembly speedVSAvoidcrash sensor response time
Core Design Contradiction:
ProductivityVSSpeed

Solution Approach 1:

The crash sensor is pre-mounted and pre-calibrated within the housing assembly during manufacturing, with all electrical connections and sealing elements pre-installed. This preliminary action ensures the sensor is ready for immediate operation upon installation, eliminating assembly delays that would postpone response time.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The mounting assembly includes self-aligning features and self-fastening elements that automatically position and secure the assembly to the vehicle structure without requiring complex alignment procedures or multiple adjustment steps, maximizing assembly speed.

Inventive Principle:
Principle #25Self-service

3Loss of time

If simple fastening methods are used, then assembly is quick, but water ingress risk increases compromising electrical circuitry

Engineering Contradiction:
Improveassembly timeVSAvoidwater ingress to electrical components
Core Design Contradiction:
Loss of timeVSObject-affected harmful factors

Solution Approach 1:

A flexible sealing element or gasket is incorporated into the mounting assembly, conforming to the vehicle structure surface and creating a water-tight barrier. This flexible film allows for quick installation while effectively preventing water ingress to the electrical circuitry inside the housing.

Inventive Principle:
Principle #30Flexible shells and thin films

4Reliability

If complex fastening mechanisms are used to prevent water ingress, then water protection is improved, but assembly complexity increases

Engineering Contradiction:
Improvewater seal integrityVSAvoidmounting structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The sealing function is merged with the mounting bracket structure itself, where the bracket includes integrated sealing flanges or grooves that form water-tight joints with the vehicle structure. This combination eliminates the need for separate complex sealing mechanisms while maintaining reliable water protection.

Inventive Principle:
Principle #5Merging (Combining)

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 snap fit mounting assembly enables rapid and secure attachment of crash sensors, ensuring timely response to side impacts and maintaining the integrity of the electrical components by preventing water ingress, thus enhancing the reliability of occupant protection systems.

Implementation Method 1

At least one retaining member attached to the protrusion and adapted to deform when received in an opening of a mounting structure and form an interference fit with the mounting structure

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Data Source

PatentEP3318449B1Apparatus for snap fit mounting a crash sensor
Publication Date: 2019.07.10 TRW AUTOMOTIVE US LLC
  • EP3318449B1 patent drawingFigure 1
  • EP3318449B1 patent drawingFigure 2
  • EP3318449B1 patent drawingFigure 3

AI summary

A vehicle crash sensor mounting arrangement comprising a housing (104); a protrusion (124) extending from the housing (104); a vehicle mounting structure (132) having an opening (130) defining a key slot (134); at least one deformable retaining member (120, 122) attached to the protrusion (124) and adapted to deform when received in the opening (130) of the vehicle mounting structure (132) and form an interference fit with the vehicle mounting structure (132) so as to hold the housing (104) to the vehicle mounting structure (132); a threaded bolt (110) extending from the housing (104) for providing a secure attachment of the housing (104) to the vehicle mounting structure (132), the threaded bolt (110) being receivable in the key slot (134) of the vehicle mounting structure (132); a nut (112) being threadably received on the threaded bolt (110) for securing the housing (104) to the vehicle mounting structure (132). The arrangement has at least one vehicle crash sensor in the housing (104) for sensing a vehicle crash condition and an electrical connector (108) for providing an electrical connection between the at least one vehicle crash sensor located within the housing (104) and an external control device.