Thermal Trigger Safety Valve for Irreversible Gas Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing safety valves for gas containers, such as those used in motor vehicles, face challenges in reliably releasing pressure and gas when both pressure and temperature limits are exceeded, often requiring complex mechanisms and potential spring forces that hinder efficient operation.
Innovation Solution
A safety valve design that incorporates a compression spring device with a specific preload travel and a thermally activatable trigger unit, where the trigger unit is longer than the preload path, allowing it to collapse and kinematically decouple the spring from the valve needle, ensuring irreversible opening and improved reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a compression spring device with preload is used to keep the valve needle sealed, then the valve remains reliably closed under normal pressure, but the force required to open the valve increases when temperature limits are exceeded
Solution Approach 1:
The patent extracts the spring device from the force transmission path by introducing a trigger unit that can be decoupled. When the trigger unit melts or fails, the spring is separated from the valve needle, eliminating the need to overcome spring preload force during emergency opening while maintaining sealing reliability when the trigger unit is intact.
Solution Approach 2:
The system transitions from a static spring-loaded sealing mechanism to a dynamic system where the trigger unit can change state (melt or fail) to alter the force requirements. This dynamic transition allows the valve to switch between high-force sealed state and low-force emergency opening state.
2Reliability
If a complex locking mechanism is added to prevent the valve from resealing, then the safety is improved, but the device complexity increases
Solution Approach 1:
The locking function is segmented into a separate locking body that can independently engage with the valve needle. This modular approach allows the locking mechanism to be added without fundamentally redesigning the entire valve system, reducing overall complexity while maintaining safety.
Solution Approach 2:
The locking body acts as an intermediary element between the valve needle and the valve body. It provides the locking function without requiring direct complex interactions between the main components, simplifying the overall mechanism while ensuring the valve remains open after trigger unit failure.
3Reliability
If the trigger unit is made longer than the preload path to ensure complete spring decoupling, then the reliability of opening is improved, but the manufacturing precision requirements increase
Solution Approach 1:
The trigger unit is pre-designed with a length greater than the spring preload path, ensuring that when it melts or fails, the spring is completely decoupled from the valve needle. This preliminary dimensional design simplifies the operational reliability while the precision requirements are managed through standard manufacturing tolerances for the preloaded spring configuration.
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 enhances the reliability and safety of the safety valve by reducing the force required to open the valve when the trigger unit collapses, allowing for efficient pressure and gas release without overcoming spring forces, thus improving safety and reliability.
Implementation Method 1
a compression spring device with a spring that is compressed by a preloading path, in particular relative to an unloaded state or relative to a state in which the spring rests against a stop, and thereby preloads the valve needle along the longitudinal axis into a sealing position
Implementation Method 2
a thermally activatable trigger unit, which has an extension or length along the longitudinal axis that is greater than the preload path, and which is designed to collapse upon reaching a trigger temperature
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a safety valve comprising a valve body with a guide bore which defines a longitudinal axis, a first opening which is formed on a base of the guide bore, and a second opening which is formed at a distance to the base along the longitudinal axis and which extends along a radial direction extending transversely to the longitudinal axis; a valve needle which is movably mounted in the guide bore of the valve body in an axial direction and which comprises a seal surface facing the first opening; a compression spring device with a spring that is compressed by a deflection and thereby biases the valve needle along the longitudinal axis into a seal position, in which the seal surface of the valve needle seals the first opening; and a thermally activatable trigger unit which has an extension along the longitudinal axis, said extension being greater than the deflection, and which is designed to collapse when a trigger temperature is reached, wherein the compression spring device is supported against the trigger unit.