US 6,766,622 · Granted 2004-07-27
The Tongue-and-Groove Patent That Revolutionized Click-Together Flooring
This patent covers the interlocking connection system that lets modern laminate and engineered wood floors snap together without nails or glue. Instead of traditional grooves, the design uses specially shaped coupling parts that lock panels tight in every direction—horizontally, vertically, and even diagonally—while a slippery coating lets them slide smoothly into place during installation.
The plain-English version
What it protects
What's protected here is a method and physical design for connecting floor panels edge-to-edge using a glue-free tongue-and-groove joint. The claim covers the specific shape of the coupling parts (the tongue on one panel, the groove on the next) that mechanically lock the panels together in three dimensions: parallel to the floor surface, perpendicular to the surface, and perpendicular to the direction of the connection itself. The sliding agent—typically a lubricant coating—is applied to at least one panel surface to reduce friction during assembly. Any competitor manufacturing interlocking floor panels with this mechanical locking geometry would infringe on this patent.
Why it matters
This patent was foundational to the modern click-lock flooring category. Before this, laminate and engineered wood floors required adhesive or fasteners, making installation slower, messier, and less reversible. The glue-free mechanical lock in all three dimensions meant homeowners and installers could assemble floors quickly without specialized tools or expertise. This innovation transformed flooring from a professional-only job into a DIY-friendly product, dramatically expanding the market. Unilin's patent gave them a significant competitive moat in the engineered flooring space during the 2000s, when click-lock became the dominant installation method.
Real-world use
Every time someone clicks laminate or engineered wood floorboards together during a DIY home renovation, they're using the mechanical locking geometry this patent describes. The satisfying snap-together fit and the ease of later disassembly are direct results of this innovation.
Original USPTO abstract
Floor covering, consisting of floor panels ( 1 ) based on a fiber-like material bound by a binding agent, more particularly MDF or HDF, which, at least at their edges, are connected to each other by means of a connection, more particularly a tongue-and-groove connection ( 2-3 ) which connection consists of coupling parts which are made in one piece with the floor panels and is shaped in such a manner that the floor panels ( 1 ) are locked glue-free in the direction parallel to the plane of the floor covering and transverse to the connection, as well as in a direction perpendicular to this plane, characterized in that, at least at the location where the floor panels ( 1 ) cooperate with each other, a sliding agent ( 12-12 A) is provided at least on one of the floor panels ( 1 ).
Patent details
- Publication number
- US 6,766,622
- Filing date
- 1999-07-20
- Grant date
- 2004-07-27
- Assignee
- Unilin Beheer B.V.
- Inventor(s)
- THIERS BERNARD PAUL JOSEPH
- CPC class
- E04F15/04
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