Sealed Housing Assembly Using Preloaded Form-Locking Seal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing sealed housings in motor vehicles face issues with maintaining tightness due to screw connections loosening from vibrations, making them prone to leaks and damage, especially in media-carrying applications where internal pressure can cause failures, and they are difficult to open for inspection or repair.
Innovation Solution
A sealed housing design using an elongate form-fitting element that connects the housing parts with a prestressing force from a compression sealing element, allowing for a non-destructive opening and accommodating different materials, such as plastic and metal, while maintaining a secure seal without screws.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If screw connections are used to connect housing parts, then the housing can be assembled and disassembled, but the screw connections loosen due to vibrations causing leakage
Solution Approach 1:
The patent replaces the screw connection system with a form-fitting connection system. The housing parts are designed with complementary geometric features (protrusions and recesses) that interlock without fasteners, eliminating the loosening problem while maintaining ease of assembly and disassembly.
Solution Approach 2:
The patent employs a flexible sealing element (such as a rubber or elastomeric seal) that deforms to accommodate manufacturing tolerances and vibration-induced movements, maintaining the seal integrity without requiring rigid mechanical fasteners that can loosen.
2Reliability
If welding or gluing is used to connect housing parts, then the connection is strong and vibration-resistant, but the housing cannot be opened for inspection or repair
Solution Approach 1:
The housing is divided into separate modular parts that connect through form-fitting interfaces. These interfaces provide connection strength comparable to welding while allowing the parts to be separated for inspection or repair by simply pulling the parts apart without destructive forces.
Solution Approach 2:
The patent introduces a removable sealing element as an intermediary between the housing parts. This seal maintains the connection integrity during operation but can be easily removed or replaced when the housing needs to be opened for maintenance, bridging the gap between strong connection and easy repairability.
3Weight of moving object
If plastic is used for housing to save weight, then the weight is reduced, but the housing cannot withstand high internal pressures from media
Solution Approach 1:
The patent employs composite construction where plastic housing parts are combined with reinforcing elements (such as metal inserts, ribs, or layered structures). This composite approach maintains the weight advantage of plastic while providing the pressure resistance needed for media-carrying applications through the reinforced structure.
Solution Approach 2:
The housing design applies different material properties or structural characteristics to different locations. Critical areas subjected to high pressure are locally reinforced with thicker walls, rib structures, or metal inserts, while other areas maintain the lightweight plastic construction, optimizing the weight-strength balance.
4Strength
If welded connection is used for housing parts, then the connection is permanent and strong, but only housing parts made of the same material can be joined
Solution Approach 1:
The form-fitting connection interface is designed as a universal mechanism that can join different materials (plastic, metal, composite) without requiring material-specific joining processes. The geometric interlocking provides strength regardless of the materials involved, enabling versatile assembly of multi-material housing components.
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 a reliable, weight-saving, and easily manufacturable sealed housing that can withstand internal pressures and vibrations, ensuring a secure seal without the need for screws, allowing for inspection and repair without damaging the housing.
Implementation Method 1
The form-fitting element is provided between opposing contact surfaces for the form-fitting element of the lower housing part and the upper housing part and is prestressed by a compression sealing element
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a sealed housing (2) of a device to be installed in a motor vehicle, in particular an electric heating device, comprising a housing lower part (4) and a housing cover (6) which rests against the housing lower part (4) with a sealing element (24) interposed, wherein an elongated positive locking element (60, 70, 90) connecting the housing lower part (4) and the housing cover (6) in a positive locking manner is provided between opposing contact surfaces (50) of the housing lower part (4) and a housing cover (6) and rests against the contact surfaces (50) under a preload force caused by compression of the sealing element (24).Furthermore, the present invention relates to a method for manufacturing a sealed housing (2) of a device to be installed in a motor vehicle, in particular an electric heating device, comprising a housing lower part (4) and a housing cover (6) which abut each other with a sealing element (24) interposed, wherein the housing lower part (4) and the housing cover (6) are first manufactured as separate components, are placed against each other with the sealing element (24) interposed and compressed, wherein an external force is applied to the housing lower part (4) or the housing cover (6) to compress the sealing element (24), an elongated positive locking element (60, 70, 90) is inserted in a direction substantially parallel to a main extension direction of the sealing element (24) between opposing contact surfaces (50) of the housing lower part (4) and the housing cover (6), and the housing lower part (4) or the housing cover (6) is thenthe housing cover (6) is relieved of the external force, causing the contact surfaces (50) to press against the elongated form-locking element (60, 70, 90) under a preload force of the sealing element (24).