Vehicle Safety Actuator Layout for Accessible ECU Connection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing safety devices in vehicles, such as hood lifters and seat belt pretensioners, face challenges in easy mounting and connection to the vehicle's ECU, especially in narrow spaces like the engine compartment, and require expensive integrated cable harnesses, which are not easily accessible due to the placement of the gas generator and power connector.

Innovation Solution

A safety device design featuring a piston arrangement with a supporting element that projects outside the housing, allowing the gas generator to be positioned outside and connected to the supporting element, facilitating its movement with the piston and enabling easier access to the power connector for connection to the vehicle's ECU, while also using a modular design with spacers and over-moulding for sealing and adaptability to space constraints.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the gas generator and power connector are arranged inside the housing, then the actuator structure is compact, but the power connector becomes hard to access for connection to the vehicle's ECU

Engineering Contradiction:
ImproveAccessibility of power connectorVSAvoidActuator structure
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The gas generator is extracted from the housing and positioned outside on the supporting element. This allows the power connector to be accessible for connection to the vehicle's ECU while maintaining a relatively simple actuator structure. The supporting element serves as an external mounting platform for the gas generator, separating it from the housing interior.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If an integrated cable harness is used to connect the actuator to the ECU, then the connection is sealed and protected from moisture, but the cost of the actuator increases significantly

Engineering Contradiction:
ImproveSealing against moistureVSAvoidActuator cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The vehicle's existing cable system is utilized to connect the actuator to the ECU, eliminating the need for an expensive integrated cable harness. The power connector is designed to interface with the vehicle's standard electrical infrastructure, allowing the actuator to leverage the vehicle's existing electrical infrastructure rather than requiring a custom integrated solution.

Inventive Principle:
Principle #25Self-service

3Ease of operation

If the gas generator is positioned outside the housing on the supporting element, then the power connector is more accessible, but the gas chamber volume may be reduced

Engineering Contradiction:
ImproveAccessibility of power connectorVSAvoidGas chamber volume
Core Design Contradiction:
Ease of operationVSVolume of stationary object

Solution Approach 1:

The gas generator is repositioned from the interior three-dimensional space of the housing to an external position on the supporting element. This dimensional relocation allows the gas chamber inside the housing to maintain its full volume while the power connector remains accessible on the exterior. The supporting element extends the functional space outward, resolving the spatial conflict between internal volume and external accessibility.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

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 design simplifies the mounting and connection of safety devices to the vehicle's ECU, reduces the need for integrated cable harnesses, and enhances accessibility and adaptability to various vehicle spaces, ensuring reliable operation and reduced risk of damage from impacts.

Implementation Method 1

a piston arrangement (5) comprising a piston (5a) and a piston rod (5b), the piston arrangement (5) being adapted to fit in the housing (1) and to be moved from a retracted position to an extended position

Methodology Applied
Scientific EffectGas pressure: Pressure Increase

Data Source

PatentEP4289684B1A safety device in a vehicle
Publication Date: 2024.09.04 AUTOLIV DEV AB
  • EP4289684B1 patent drawingFigure 1
  • EP4289684B1 patent drawingFigure 2
  • EP4289684B1 patent drawingFigure 3~4

AI summary

A safety device in a vehicle is provided. The safety device comprises an actuator (100) comprising a housing (1) having a first end (2) and a second end (3), a piston arrangement (5) comprising a piston (5a) and a piston rod (5b), the piston arrangement (5) being adapted to fit in the housing (1) and to be moved from a retracted position to an extended position, a gas generator (13) and a power connector (14) being configured to power the gas generator (13). A gas chamber (11) is formed between an inner envelope wall of the housing and a pressure surface (10) of the piston (5a) facing the first end (2) of the housing (1). The piston rod (5b) has a supporting element (12) projecting outside the housing (1). The gas generator (13) is situated in a position outside the housing (1) supported by the supporting element (12) and in communication with the gas chamber (11).