Pressure cooker with improved safety
Solution Overview
Problem
Conventional pressure cookers lack reliable and controlled mechanisms for safe depressurization in case of accidental excess pressure, leading to unpredictable steam release and potential safety hazards due to the absence of precise control over the radial movement of the sealing gasket and variability in pressure threshold activation across different models.
Innovation Solution
A pressure cooker design featuring a sealing gasket with a flexible lip that deforms to open a leakage opening in the lid when pressure exceeds a safety threshold, allowing controlled steam release without radial movement through a window, ensuring consistent and safe depressurization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a window is formed in the lid to allow radial movement of the gasket for safety depressurization, then steam can escape to reduce pressure, but the lid's mechanical strength is reduced and violent steam release may occur
Solution Approach 1:
The gasket is segmented into a fixed annular ring and a movable flexible lip. The ring remains fixed to maintain sealing and structural integrity, while only the flexible lip moves to open the leakage opening when needed, allowing controlled steam release without compromising lid strength.
Solution Approach 2:
The gasket has different properties in different regions: the annular ring is rigid and fixed to maintain structural integrity, while the flexible lip is designed to be deformable to allow controlled movement for steam escape. This local differentiation resolves the contradiction between maintaining strength and enabling safety depressurization.
2Reliability
If the gasket is allowed to move radially outward through a window for safety function, then pressure can be reduced, but the pressure threshold becomes unpredictable and varies across models
Solution Approach 1:
The flexible lip is designed with specific dynamic properties (flexibility, thickness, material characteristics) that allow it to deform at a predictable pressure threshold. The lip's controlled deformation through the leakage opening provides consistent and reliable pressure control, eliminating the variability associated with radial movement through a window.
Solution Approach 2:
The invention changes the movement mechanism from radial displacement to local deformation. By controlling the deformation parameters of the flexible lip (thickness, material properties, geometry), the pressure threshold for steam release becomes precise and consistent across different models, improving measurement precision while maintaining reliability.
3Reliability
If conventional safety devices are used, then pressure can be controlled, but they may fail due to ageing, soiling, clogging, or blocking
Solution Approach 1:
The flexible lip safety mechanism is passive and self-activating based on pressure conditions alone, without moving parts that can wear, clog, or block. It automatically opens the leakage opening when pressure exceeds the threshold and closes when pressure normalizes, providing long-lasting reliable safety function without maintenance, thus extending device lifespan.
Solution Approach 2:
The flexible lip is designed as a simple, maintenance-free component that relies on elastic deformation rather than mechanical moving parts. This simplifies the safety mechanism, eliminating failure modes associated with conventional devices (ageing, soiling, clogging) and ensuring long-term reliability without requiring replacement or maintenance.
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 solution provides reliable, controlled, and safe depressurization of the pressure cooker, reducing the risk of violent steam release and ensuring consistent operation across different models by utilizing a flexible lip to open a leakage opening, thus maintaining mechanical strength and user safety.
Implementation Method 1
the first lip presenting flexibility that is appropriate for the free end portion to be pushed back locally through the leakage opening as soon as the pressure that exists inside the enclosure exceeds said safety threshold
Implementation Method 2
said sealing gasket comprising a peripheral annular ring together with a first flexible lip projecting from said ring towards the inside of the utensil... with a second lip extending from said ring in a direction that is mainly radially inwards towards the inside of the utensil, said second lip being designed to come into sealing contact with the vessel
Data Source
AI summary
The invention relates to a pressure cooking utensil comprising a vessel, a lid with an annular skirt, and a gasket interposed between the lid and the vessel, said gasket including a ring and a first lip in sealing contact with the top wall of the lid, said utensil being characterized in that it includes a leakage opening formed through said top wall, the annular skirt forming a stop abutment for the ring, said first lip presenting flexibility that is suitable, when the pressure that exists inside the enclosure exceeds a safety threshold, for causing the inside of the enclosure to communicate with the outside through the leakage opening.