US 4,242,390 · Granted 1980-12-30
The Interlocking Floor Tile That Changed How Rooms Lock Together
Imagine floor tiles that click together like puzzle pieces instead of lying flat and loose. This patent describes tiles with a decorative top layer fused to a sturdy backing, with grooves and tongues cut at special angles so they grip each other when placed side by side.
The plain-English version
What it protects
What's protected here is a two-layer floor tile design where a decorative, wear-resistant surface layer sits on top of a carrier base, with the two layers extending unevenly past each other on different sides. The key innovation is the angled groove-and-tongue interlocking system cut into the edges—the specific angular cuts that let adjacent tiles lock together mechanically. The claim covers both this basic design and variations where the groove and tongue angles differ from each other.
Why it matters
This patent solved a real installation problem: floor tiles that stay put without relying entirely on adhesive or grout. By engineering tiles to physically interlock, manufacturers could offer faster, easier installation and better stability underfoot. For a cork flooring company like Wicanders, this meant a competitive advantage in durability and customer appeal during a time when DIY home improvement was growing.
Real-world use
Every time you walk across a modern interlocking vinyl plank or laminate floor in a kitchen or bedroom, you're stepping on geometry directly descended from this 1980 patent—tiles that grip each other at the seams rather than floating freely.
Original USPTO abstract
Floor tiles are disclosed which comprise a carrier layer and a superimposed floor surface forming layer which is provided with a decorative wear resistant surface. In one embodiment the carrier layer protrudes beyond the floor surface layer on two sides and the floor surface layer protrudes beyond the carrier layer on the other two sides and the floor surface forming layer defines an angular groove and a bevelled tongue to enable adjacent tiles to be interlocked. In an alternative embodiment of the invention the groove and tongue are formed to have different angles.
Patent details
- Publication number
- US 4,242,390
- Filing date
- 1978-03-22
- Grant date
- 1980-12-30
- Assignee
- Ab Wicanders Korkfabriker
- Inventor(s)
- NEMETH, JOZSEF
- CPC class
- E04F15/181
Want to file your own patent?
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