US 5,348,778 · Granted 1994-09-20
The Sandwich Panel Patent That Sealed Buildings Airtight
Imagine building panels made of foam sandwiched between two hard shells—like a cookie-and-cream bar for walls. This patent covers how to lock those panels together with special grooved edges so no air or water leaks through the seams, making super-efficient insulation for buildings.
The plain-English version
What it protects
The claim covers sandwich-structured panels with rigid polyurethane foam cores faced with outer shells, specifically protected when joined using interlocking edge profiles made of flexible polyurethane foam. What's protected is the specific combination of the groove-and-tongue edge joint design that creates airtight and watertight seals between adjacent panels, preventing infiltration at panel seams.
Why it matters
This patent addresses a critical problem in construction: sealing the gaps between insulation panels. By creating an interlocking foam edge joint, the design eliminates the need for separate sealants or gaskets, simplifying assembly and improving building envelope performance. The rigid foam core provides thermal insulation while the flexible foam edges absorb movement and vibration, making the system durable and reliable in both residential and commercial applications.
Real-world use
When you walk into a modern warehouse, office building, or refrigerated facility, the walls beneath the surface likely use sandwich panels locked together with this groove-and-tongue sealing system to maintain temperature control and prevent air leaks.
Original USPTO abstract
Sandwich elements in the form of slabs, shells and the like, consisting of facings and a rigid polyurethane foam core can be joined together in an airtight and watertight manner when they are provided with edge profiles which are cast from casting materials forming flexible polyurethane foam and which have a groove and a tongue.
Patent details
- Publication number
- US 5,348,778
- Filing date
- 1993-10-26
- Grant date
- 1994-09-20
- Assignee
- Bayer Aktiengesellschaft
- Inventor(s)
- KNIPP; ULRICH, SKOUPI; DIETER
- CPC class
- B32B3/06
Want to file your own patent?
If you're designing a new building component or insulation system, search IsItPatented free to see what sandwich panel and foam joint patents might already exist in your space.
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