1. Field of the Invention
This invention relates to a panel, such as, for example, to a floor panel, a ceiling panel, a wall panel or the like.
More particularly, it relates to a panel, which, at least at two opposite sides, comprises coupling parts, in the form of a male coupling part and a female coupling part, respectively, which allow that two of such panels can be connected to each other at said sides, or, in other words, can be brought in a coupled condition, by providing one of these panels with the pertaining male coupling part, by means of a downward movement, in the female coupling part of the other floor panel, such that thereby at least a locking in horizontal direction is obtained.
2. Related Art
Couplings allowing that two panels, such as floor panels, can be coupled to each other by inserting one floor panel with a downward movement into the other, in practice are divided into two types, namely a first type, wherein the coupling parts provide exclusively for a horizontal locking, without any locking in vertical direction, and a second type, wherein a horizontal as well as vertical locking is provided.
The couplings of the first type are also known as so-called “drop-in” systems. Floor panels which are provided therewith at two opposite sides are known, amongst others, from CA 991 373 and JP 07-300 979. As becomes evident from these patent documents, such “drop-in” systems often are applied on a first pair of opposite sides of the floor panels only, whereas then on the second pair of opposite sides coupling parts are applied, which, in the coupled condition of two floor panels, provide for a vertical as well as for a horizontal locking and which allow that two of such floor panels can be coupled to each other by means of an angling movement. Floor panels with such a combination of coupling parts offer the advantage that they can be easily installed in rows in a successive manner, simply by coupling each newly to install floor panel to the preceding row of floor panels by means of the angling movement and by providing for, during the angling down, that such floor panel at the same time also engages in an already installed preceding floor panel of the same row. Thus, installing such floor panel requires only an angling and putting down-movement, which is a particularly user-friendly installation technique.
A disadvantage of floor panels with such coupling parts consists in that, due to the fact that there is no locking in vertical direction, height differences among the coupled floor panels may occur on the upper surface. For example, such floor panels in a first or last row of a floor covering can turn upward again from their flat position if they are not held downward by a skirting board or the like. Even if such floor panels are provided with a “drop-in” system on only one pair of sides, whereas they are locked at their other pair of sides in horizontal as well as in vertical direction in respect to adjoining floor panels, height differences among adjoining floor panels can occur at the sides which are coupled by the “drop-in” system, amongst others, when two adjoining floor panels are loaded differently, or when one floor panel should warp somewhat and bend in respect to the other.
Couplings of the aforementioned second type, also called “push-lock” systems, attempt to remedy the aforementioned disadvantage by also providing a vertical locking. Such so-called “push-lock” systems can be divided into two different categories, namely one-piece embodiments and embodiments comprising a separate locking element which is made as an insert, which either is or is not fixedly attached to the actual floor panel.
One-piece embodiments are known, amongst others, from the patent documents DE 299 24 454, DE 200 08 708, DE 201 12 474, DE 10 2004 001 363, DE 10 2004 055 951, EP 1 282 752 and EP 1 350 904. The known one-piece embodiments have the disadvantage that they work relatively difficult and that a good interconnection of two floor panels cannot always be guaranteed.
Embodiments comprising a separate locking element, which assists in a vertical and possibly also horizontal locking between two coupled floor panels, are known, amongst others, from the patent documents DE 20 2007 000 310, DE 10 2004 001 363, DE 10 2005 002 297, EP 1 159 497, EP 1 415 056 B1, EP 1 818 478, WO 2004/079130, WO 2005/054599, WO 2006/043893, WO 2006/104436, WO 2007/008139, WO 2007/079845, WO 2009/066153, WO 2010/082171 and SE 515324. The use of a separate locking element offers the advantage that the material thereof is independent from the actual floor panel and thus can be chosen optimally in function of the application. In this manner, such inserts can be realized from synthetic material or metal, by which relatively strong, however, still easily movable locking portions can be realized, which can take up relatively large forces with a minimum contact surface.