Patent Description:
Building panels provided with a mechanical locking system comprising a displaceable and resilient tongue cooperating with a tongue groove for vertical locking are known and disclosed in, e.g., <CIT> and <CIT>. The tongue is a separate part and is made of, e.g., plastic and inserted in a displacement groove at an edge of a panel. The tongue is pushed into the displacement groove during a vertical assembling of the panels and springs back into the tongue groove of an adjacent panel when the panels have reached a locked position.

Further known locking system comprises a tongue provided with, e.g., a wedge element. Two adjacent panels' edges are locked by displacing the tongue along the adjacent edges, see e.g., is disclosed in <CIT>.

A known system for unlocking panels comprises, and is disclosed in <CIT>.

Although <CIT> provides a well-functioning system, there is still room for improvements.

A further known locking system for panels is - disclosed in <CIT>.

The above description of various known aspects is the applicant's characterization of such, and is not an admission that any of the above description is considered as prior art.

It is an object of certain embodiments of the present invention to provide an improvement over the above described techniques and known art. Particularly the ease of assembling and disassembling panels may be improved by embodiments of the inventive concept. Also, the inventive concept may bring about advantages in the manufacturing of the panels, in particular in terms of manufacturing tolerances of the edge-portions of the panels, as will become apparent herein.

The invention is defined as in the appended claims.

At least some of these and other objects and advantages that will be apparent from the description have been achieved by aspects of the inventive concept. According to the invention, in a first aspect, there is provided a set of essentially identical panels, such as building panels, provided with a mechanical locking system comprising:
a displaceable tongue arranged in a displacement groove having a first opening at a first edge of a first panel. The tongue is configured to be displaced in the displacement groove along a displacement axis to attain a locking state wherein a first portion of the tongue cooperates with a first tongue groove having a second opening at a second edge of an adjacent second panel, for vertical locking of the first and the second edge. A second portion of the tongue is configured to cooperate with the second edge of the adjacent second panel via an elongated element for vertical unlocking of the first and the second edge.

The arrangement may bring about an advantage in that the tolerances necessary to achieve a reliable unlocking mechanism are provided by the tongue and the elongated element.

According to the invention, a first engagement portion of the second portion is configured to engage with the elongated element and delimits an unlocking groove configured to receive the elongated element such as to cause the tongue to be displace along the displacement axis to attain an unlocking state for said vertical unlocking of the first and the second edge.

According to the invention, a second engagement portion of the second edge is configured to engage with the elongated element and delimits the unlocking groove, the second engagement portion being provided external the first tongue groove, preferably externally of and below the first tongue groove.

In a yet further embodiment, the first engagement portion and/or the second engagement portion are planar and extend in parallel or substantially in parallel, preferably side by side and in parallel. It may thereby be achieved that the elongated element is not urged in a transverse direction thereof, such as up or down. Also, linear translation of the tongue may be obtained.

In a still further embodiment, the unlocking groove is configured to attain the unlocking state upon receiving an elongated element having a constant cross-sectional width in the longitudinal direction of the elongated element.

The displacement groove may comprise a bottom surface, an upper surface and a lower surface, preferably the lower surface being parallel to the upper surface and/or parallel to the displacement axis of the tongue.

In one embodiment, the second engagement portion extends below a plane of the lower surface.

A dimension in the direction of a normal of a plane of the lower surface, between the lower surface and the first portion, may correspond at least to a maximum diameter of the elongated element, such as a maximum diameter of a portion of the elongated element intended to be received in the unlocking groove.

In one embodiment, a dimension in the direction of the normal of a plane of the lower surface, between the lower surface and the first portion, corresponds at least to a dimension along the displacement axis between the first engagement portion and an outermost point of the tongue.

A dimension in the direction of the normal of the plane of the lower surface, between the said plane and the first portion may correspond at least to a distance, such as a greatest distance, along the displacement axis between the second engagement portion and an outermost point of the tongue in the locking state, preferably the said greatest distance is measured between an outermost point of the second engagement portion and an outermost point of the tongue.

The dimension in the direction of a normal of a plane of the lower surface, between the lower surface and the first portion may be measured between a point on a lower surface of the first portion of the tongue, said point being aligned, in the direction of the normal of the plane of the lower surface, with an uppermost point of the elongated element.

In one embodiment, the second portion and the diameter of the elongated element are configured to cooperate such that the tongue is displaced along the displacement axis at least to the extent that an outermost point of the second engagement portion and an outermost point of the first portion do not overlap, preferably to the extent that there is provided a play in a horizontal plane between the outermost point of the second engagement portion and the outermost point of the first portion.

The second portion may comprise a chamfered edge portion forming a guiding surface configured to guide the elongated element in the transverse direction of the tongue, preferably a chamfered longitudinal edge portion.

In one embodiment, the second edge comprises a chamfered edge portion for guiding said elongated element towards the tongue.

The elongated element may have a rotationally symmetric cross-section in a transverse plane thereof, by an angle of less than <NUM> degrees, preferably less than <NUM> degrees, more preferably being circular.

The locking system may be configured such that in the unlocking state, the elongated element is at least partially arranged in the displacement groove.

An engagement direction may be directed downwards and in parallel with vertical plane formed by an upper part of the first edge and an upper part of the second edge.

In the locking state, the first portion of the tongue may be configured to protrude from the displacement groove and/or from the first edge, such as an upper part thereof, a distance along the horizontal plane, which may be transverse the engagement direction, not greater than the distance between a lower surface of the displacement groove and the first portion of the tongue in the direction of a normal of the lower surface of the displacement groove.

In one embodiment, the unlocking groove is disposed at least partially between the tongue groove and the lower surface of the displacement groove.

In one embodiment, the second engagement portion forms part of a second unlocking surface of the second edge facing a first unlocking surface of the second portion of the tongue. The second unlocking surface may extend in an engagement direction and at least passed a mid-point between the first portion of the tongue and the plane of the lower surface of the displacement groove. The second unlocking surface may extend at least to the plane of the lower surface of the displacement groove. The first and second unlocking surfaces may be planar and/or vertical. Optionally, the first and second unlocking surfaces may each have an extension configured such that the elongated element is not urged to displace in the engagement direction above or below the displacement groove.

The extension of the second portion in a direction along the normal of the lower surface of the displacement groove may exceed the extension of the first portion in a direction along the said normal.

The first engagement portion may be provided at a recess of the tongue. The recess may be provided between the first portion and the lower surface of the displacement groove.

The recess may have a concave shape. An advantage of providing the recess with a concave shape may be that the elongated element maintains a desired position in the unlocking groove, such as during insertion of the elongated element in the unlocking groove and/or during disassembling of the first and second panel.

The first opening and the second opening are preferably horizontally open and a vertical height of the first opening is preferably greater than a vertical height the second opening.

A maximum height of the displacement groove may be greater than a maximum height of the first tongue groove. The maximum height of the first tongue groove may be in the range of about <NUM>% to about <NUM>% of the maximum height of the displacement groove, preferably in the range of about <NUM>% to about <NUM>% of the maximum height of the displacement groove.

The mechanical locking system may comprise a first locking strip, at the first or the second edge, provided with a first locking element configured to cooperate for horizontal locking with a first locking groove at the other of the first or second edge.

The panels may be floorboards, wall panels, ceiling panels, a furniture component or the like.

The core of the panels may be a wood-based core, preferably made of MDF, HDF, OSB, WPC, plywood or particleboard. The core may also be a plastic core comprising thermosetting plastic or thermoplastic e.g. vinyl or PVC. The plastic core may comprise fillers. The thinner first tongue groove may, for a panel with a core comprising plywood, be easier to arrange at a favourable position in relation to the layers in the plywood core.

The front face, such as an upper surface, of the panels is preferably provided with a decorative layer and the back face is preferably provided with a balancing layer.

The edge of the panels, of which parts of the locking system, such as the first and the second locking strip, the first and the second locking element, the first and the second locking groove, the displacement groove and the first and the second tongue groove, may be made, may be comprised of one or more of the above-mentioned core materials.

In a second aspect, the inventive concept pertains to a kit comprising the set according to any one of the embodiments of the first aspect and an elongated element configured for vertical unlocking of the first and second edge.

In a third aspect, the inventive concept pertains to a method for vertical unlocking a set of essentially identical panels, such as building panels, provided with a mechanical locking system comprising:.

In a fourth aspect, the inventive concept pertains to a device <NUM> for unlocking a mechanical locking system of building panels assembled by means of the mechanical locking system. The mechanical locking system configured for horizontal and vertical locking of adjacent building panels. The locking system comprising at a first edge of a first building a displaceable locking tongue configured to displace in a displacement groove provided in the first edge of the first building panel. The locking tongue being configured to displace between a locking position and an unlocking position. In the locking position, the locking tongue is configured in a protruding position wherein protruding from the displacement groove for cooperating with a tongue groove provided in an adjacent edge of a second adjacent building panel. In the unlocking position, the locking tongue is configured in a retracted position. The unlocking device comprises an elongated element (<NUM>) and a positioning element (<NUM>). The positioning element is configured to be received in the displacement groove.

Further embodiments and advantages being described in following description and the appended claims.

The present invention will by way of example be described in more detail with reference to the appended schematic drawings, which shows embodiments of the present invention.

A known mechanical locking system for building panels, which comprises a displaceable tongue <NUM>' cooperating with a first tongue groove <NUM>' for vertical locking of a first edge of a first panel <NUM>' with a second edge of a second panel <NUM>' is shown in <FIG>. The tongue <NUM>' is a separate part and is made of, e.g., plastic, and inserted in a displacement groove <NUM>' at the first edge of the first panel <NUM>'. The tongue <NUM>' is pushed into a displacement groove <NUM>' during a vertical assembling of the first and the second edges of the panels <NUM>', <NUM>' and springs back into a first tongue groove <NUM>' at the second edge of the second panel <NUM>' when the panels have reached a locked position. A third and a fourth edge of the panels are provided with a locking system, which enables assembling to an adjacent panel (not shown) by an angling movement, to obtain a simultaneous assembling of the first and the second edges and the third and the fourth edges.

Embodiments of the inventive concept are shown in <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, <FIG>, and <FIG>. A locking system is formed at a first edge <NUM> of a first panel <NUM>, and a second edge <NUM> of an adjacent second panel <NUM> for locking the first <NUM> and the second edges <NUM> in a vertical and/or horizontal direction.

<FIG> show an illustration of an embodiment of the inventive concept comprising a mechanical locking system comprising a dedicated unlocking groove <NUM> configured to receive an elongated element <NUM> for vertical unlocking of the first and second edges <NUM>, <NUM>.

<FIG> show side views of embodiments of the displaceable tongue <NUM> during unlocking of a first and a second panel <NUM>, <NUM>.

An upper part of the first edge <NUM> and an upper part of the second edge <NUM> may form a vertical plane V.

The second panel <NUM> with the first tongue groove <NUM> is lowered in relation to the second panel <NUM> with the displaceable tongue <NUM>, which is pushed into a displacement groove <NUM> by the lowered panel <NUM>. The displaceable tongue <NUM> springs back, and into the first tongue groove <NUM>, when the panels have reached an assembled position, and locks the first <NUM> and the second <NUM> panels vertically.

An embodiment of the locking system enables assembling of panels at the adjacent edges by a vertical movement. The locking system is preferably formed by mechanical cutting, such as milling, drilling and/or sawing, of the edges of the panels and provided with a displaceable tongue <NUM>, preferably made of a polymer-based material such as thermoplastic, alternatively the tongue <NUM> may be made of metal. The displaceable tongue <NUM> may be bendable and may be provided with protruding flexible parts, such as biasing feathering means. Obtaining small satisfactory tolerances in the forming of the locking system, in particular the machining of the panels, are typically costly and time consuming. Embodiments of the present disclosure may facilitate that manufacturing tolerances of the locking system may be essentially provided by the tongue <NUM> and the deactivating elongated element <NUM>, such as a stick. The stick may be made of a stiff and bendable material, such as metal. The tongue <NUM> and the elongated element <NUM> may thus be manufactured such that the elongated element <NUM> may cause displacement of the tongue <NUM> in the unlocking direction to the extent that play dH (See <FIG>) in the direction of the plane H, such as a horizontal plane, is provided between the first portion <NUM> of the tongue <NUM> and a second engagement portion <NUM> independent of the tolerances of the first <NUM> and second edge <NUM>, for vertical unlocking of the first and second edges <NUM>, <NUM>. In some embodiments, dH may be zero. Thereby, embodiments of the inventive concept may provide for improvements in terms of cost-efficiency since it may be less costly to manufacture the tongue <NUM> and the deactivating elongated element <NUM> with high precision.

The displaceable tongue <NUM> is arranged in the displacement groove <NUM> at the first edge <NUM> of the first panel <NUM>. The tongue <NUM> cooperates with a first tongue groove <NUM>, which is formed at the second edge <NUM> of a second panel <NUM>, for vertical locking of the panel <NUM>, <NUM>. A corresponding configuration may be provided at a first edge <NUM> of the second panel <NUM>. A first locking strip <NUM> with a vertically protruding first locking element <NUM> is formed in the first edge <NUM> of the first panel <NUM>. The locking element <NUM> cooperates with a first locking groove <NUM>, formed in the second edge <NUM> of the second panel <NUM>, for horizontal locking of the panels <NUM>, <NUM>.

The tongue <NUM> may be displaceable in the displacement groove <NUM> along a displacement axis Ax corresponding to a locking direction to attain a locking state wherein a first portion <NUM> of the tongue <NUM> is configured to cooperate with the first tongue groove <NUM> having an opening at a second edge <NUM> of an adjacent panel, such as second panel <NUM>, for vertical locking of the first edge <NUM> and the second edge <NUM>.

The tongue <NUM> may be displaced in the displacement groove <NUM>, in particular, a first portion <NUM> and a second portion <NUM> of the tongue <NUM> are configured to be displaced inside the displacement groove <NUM>. The first <NUM> and second <NUM> portions of the tongue <NUM> may form an integral body. The tongue <NUM> may be linearly translated in the displacement groove <NUM>. Linear translation may include a minor amount of non-linear translation, such that the translation is primarily linear.

As shown for instance in <FIG> and <FIG>, the displacement groove <NUM> comprises a bottom surface <NUM>, an upper surface <NUM> which may be disposed adjacent the first portion <NUM> of the tongue <NUM>, and a lower surface <NUM> which may be disposed adjacent the second portion <NUM> of the tongue <NUM>. Plane Px of the lower surface <NUM> may be parallel to a displacement axis Ax. Consequently, the tongue <NUM> may be displaced along the displacement axis Ax relative to and/or against the lower surface <NUM>, optionally also the upper surface <NUM>. The tongue <NUM> may be displaced, typically linearly translated, along the displacement axis Ax in a locking direction to attain the locking state and in an unlocking direction to attain an unlocking state, as will be explained herein. Typically, the tongue <NUM> at least to some extent rests on the bottom surface <NUM>. Accordingly, the direction of the normal Ny of the plane Px of the bottom surface <NUM> thus extends transverse or with a right-angle relative the plane Px in a direction towards the upper surface <NUM> of the displacement groove <NUM>.

The first portion <NUM> may comprise or constitute an upper and outer portion of the tongue <NUM> and the second portion <NUM> may comprise or constitute a lower and outer portion of the tongue <NUM>. In this context, "upper" may refer to adjacent the upper surface <NUM> of the displacement groove <NUM>, correspondingly "lower" may refer to adjacent the lower surface <NUM> of the displacement groove <NUM> and "outer" may refer to opposite the bottom surface <NUM> of the displacement groove <NUM>.

As shown in <FIG>, the displacement axis Ax, and thus also the displacement groove <NUM>, may be inclined an angle φ relative a horizontal plane H. Typically, the plane of the first panel <NUM> and/or an upper <NUM> surface and/or a lower <NUM> surface of the panel may be parallel the horizontal plane H. The upper surface <NUM> of the panel <NUM>, <NUM> may be a visible surface. The displacement groove <NUM> may be inclined downwards, such as in the engagement direction E, as the displacement groove <NUM> extends into the first panel <NUM>, as shown in <FIG>.

<FIG> shows the tongue <NUM> in the locking state. In the locking state, at least the first portion <NUM> of the tongue <NUM> protrudes outside the displacement groove <NUM> and at least partially into the tongue groove <NUM>. The first portion <NUM> may comprise a protruding tongue nose of the displaceable tongue <NUM>.

The second portion <NUM> may or may not protrude outside the displacement groove <NUM>, typically the second portion <NUM> does not or does not substantially protrude from the displacement groove <NUM> in the locking state and/or the unlocking state.

The first portion <NUM> may have an extension along the displacement axis Ax exceeding that of the second portion <NUM>. The second portion <NUM> may have an extension in the normal direction Ny exceeding that of the first portion <NUM>.

The tongue <NUM> further comprises a recess <NUM>, which may recess inwards underneath the tongue nose of the tongue <NUM> to form a concavity extending in the longitudinal direction of the tongue <NUM>, such as the longest extension of the tongue <NUM>. It follows that there may be a gradual curved transition between the first portion <NUM> and the second portion <NUM> as illustrated in <FIG> which curve may have a radius of curvature configured to substantially correspond to a radius of the elongated element <NUM>. The recess <NUM> may at least partially surround the unlocking groove <NUM>.

The second portion <NUM> of the tongue <NUM> of the first panel <NUM>, provided adjacent the first portion <NUM>, may be configured to cooperate with an edge portion of an adjacent second panel <NUM> for vertical unlocking of the first <NUM> and second <NUM> panels. The second portion <NUM> of the tongue <NUM> may be provided above or below the protruding tongue nose, preferably below the first portion <NUM> in the engagement direction, such as downwards in <FIG>, <FIG>. More in particular, the second portion <NUM> is configured to cooperate with a portion of the second edge <NUM> via an elongated element <NUM> which may abut the second portion <NUM> and the second edge <NUM> simultaneously. The second portion <NUM> comprises a first engagement portion <NUM> and the second edge <NUM> comprises a second engagement portion <NUM> for engaging the elongated element <NUM>.

The mechanical locking system comprises an unlocking groove <NUM> for vertical unlocking of the first edge <NUM> of the first panel <NUM> and the second edge <NUM> of an adjacent panel, such as the second panel <NUM>.

As shown in <FIG>, the first edge <NUM> and the second edge <NUM> of the first panel <NUM> may be the short edges of a panel, such as the first panel <NUM>, and the third edge <NUM> and the fourth edge <NUM> may be the long edges of a panel, such as the first panel <NUM>. This may apply mutatis mutandis for an adjacent panel, such as the second panel <NUM> having respective first <NUM>, second <NUM>, third <NUM>, and fourth edges <NUM>.

The unlocking groove <NUM> is delimited by surfaces of elements, such as two, three or four surfaces, provided by portions of one or more of the first portion <NUM> of the tongue <NUM>, the second portion <NUM> of the tongue <NUM>, the second edge <NUM> of the second panel <NUM> and the lower surface <NUM> of the displacement groove <NUM>.

Thus, the second portion <NUM>, the second edge <NUM> and the lower surface <NUM> of the displacement groove <NUM> may form the unlocking groove <NUM> configured to receive the elongated element <NUM>.

Typically, the unlocking groove <NUM> is delimited in the normal direction Ny by means of the first portion <NUM> of the tongue <NUM>, such as the protruding tongue nose, and further delimited by the second portion <NUM> of the tongue <NUM> and by a portion of the second edge <NUM> of the second panel <NUM>.

The unlocking groove <NUM> is configured to receive an elongated element <NUM> such that the tongue <NUM> is displaced along the displacement axis in an unlocking direction, to attain an unlocking state as shown in <FIG>.

Upon insertion of the elongated element <NUM> in the unlocking groove <NUM>, the tongue <NUM> is thus caused to displace or linearly translate inside the displacement groove <NUM> in response to the insertion, i.e. under the action of the elongated element <NUM> engaging the tongue <NUM> and urging the tongue <NUM> to displace along the displacement direction Ax.

The second portion <NUM> of the tongue <NUM> comprises a first engagement portion <NUM> for direct engaging or cooperating with the elongated element <NUM>, such as with an outer circumference of the elongated element <NUM>.

The second edge <NUM> of the second panel <NUM> may comprise a second engagement portion <NUM> (See <FIG>) provided exterior the tongue groove <NUM>, preferably below the tongue groove <NUM>. The second engagement portion <NUM> may provide for direct engaging or contact with the elongated element <NUM>, such as a circumference of the elongated element <NUM>. The first edge <NUM> of the first panel <NUM> may comprise a first engagement portion <NUM>. The first engagement portion <NUM> may provide for direct engaging or contact with the elongated element <NUM>, such as a circumference of the elongated element <NUM>.

The first engagement portion <NUM> and/or the second engagement portion <NUM> may be planar and/or may extend vertically. The first engagement portion <NUM> and the second engagement portion <NUM> may extend side by side and/or in parallel. Preferably, the first engagement portion <NUM> and the second engagement portion <NUM> are planar and extends side by side in parallel.

During a vertical assembling of the panels, the second engagement portion <NUM> may be configured to engage with the first portion <NUM> of the tongue <NUM> such as to push back the tongue <NUM> in an unlocking direction along the displacement axis Ax into the displacement groove <NUM>.

The unlocking groove <NUM> may be configured such that the extension thereof in the direction Ny of the normal corresponds to at least the distance between the first engagement portion <NUM> and the second engagement portion <NUM> in the unlocking position as shown in <FIG>.

Typically, in the locking state, the unlocking groove <NUM> is configured such that the first engagement portion <NUM> and the second engagement portion <NUM> are provided to have an extension above the lower surface <NUM> of the displacement groove <NUM>. For example, the first engagement portion <NUM> and the second engagement portion <NUM> are provided to have an extension at least at a distance above the lower surface <NUM> of the displacement groove <NUM> substantially corresponding to half the distance between the first and second engagement portions <NUM>, <NUM> in the unlocking state or for example the first engagement portion <NUM> and the second engagement portion <NUM> are provided to have an extension at least at a distance above the lower surface <NUM> of the displacement groove <NUM> substantially corresponding to half the distance between the plane Px and the first portion <NUM> of the tongue <NUM> in the Ny direction inside the unlocking groove <NUM>. The second engagement portion <NUM> may have an extension below a first opening of the displacement groove <NUM> at the first edge <NUM>.

The second portion <NUM> of the tongue <NUM> may be disposed exterior the tongue groove <NUM> in the locking state and/or unlocking state.

In particular, the first engagement portion <NUM> may be disposed exterior the tongue groove <NUM> in the locking state and/or in the unlocking state.

The unlocking groove <NUM> may be configured such that the tongue <NUM> is displaced in an unlocking direction to attain an unlocking state upon receiving the elongated element <NUM> which is preferably rotational symmetric, such as rotational symmetric under an angle of <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> degrees, preferably rotational symmetric under an angle of <NUM>, more preferably under <NUM>, most preferred being circular.

This arrangement brings about several advantageous effects, including that the elongated element <NUM> can be inserted in the unlocking groove <NUM> with reduced frictional resistance which may otherwise cause bending of the elongated element <NUM>.

Further, in the unlocking state when the respective first and second engagement portions <NUM>, <NUM> are engaged with engagement element <NUM>, the arrangement provides the function of a needle bearing and thus functions as a needle bearing as the second panel <NUM> is displaced in a direction opposite the engagement direction E, such as a vertical direction, causing the elongated element <NUM> to rotate or slide against the first engagement portion <NUM> and/or the second engagement portion <NUM>.

It should be appreciated that as the angle of rotational symmetry decreases the effective contact surfaces, i.e. frictional surfaces, between the elongated element <NUM> and the respective engagement portions <NUM>, <NUM> are reduced. Accordingly, in a preferred embodiment the elongated element <NUM> has a circular cross section in a transverse direction thereof, such as the shortest extension. In this embodiment, the circumference of the elongated element <NUM> may be tangent with the first and second engagement portions <NUM>, <NUM> only along a respective incremental contact surface of the first and second engagement portions <NUM>, <NUM>. In other words, the circumference of the elongated element <NUM> and surfaces of the locking groove <NUM>, i. the lower surface <NUM>, the first and second unlocking surfaces <NUM>', <NUM>' of the locking system may substantially not be parallel in a transverse T plane of tongue <NUM>, with exception for the contact surfaces.

Embodiments of the disclosed inventive concept enable a deactivating elongated element <NUM>, such as a round stick, or substantially round stick to be used for unlocking the first and second edge <NUM>, <NUM>.

Thus, embodiments of the disclosed inventive concept may provide for synergistic effects; by providing the unlocking groove <NUM> exterior the tongue groove <NUM>, the use of a deactivating element which substantially round or round, preferably circular, to be used for unlocking the first and second edge <NUM>, <NUM> is facilitated. The round shape of the deactivating elongated element <NUM> may substantially reduce frictional forces associated with disassembling of the panels, such as the first and second panels <NUM>, <NUM> and thus may facilitate easy vertical disassembling.

The longitudinal length of the elongated element <NUM>, such as the longest extension thereof, may correspond to at least a short side of the panel <NUM> and/or the length of the first edge <NUM> and/or in some embodiments a length sufficient to cause the entire length of the tongue <NUM> to attain the unlocking state, such as if the first edge <NUM> corresponds to a long side of a panel configured to form part of a herringbone-pattern floating floor, as will be described herein. In such case, the tongue <NUM> may optionally extend only in a portion of the displacement groove <NUM> of the long side of such panel (see <FIG> and <FIG>).

The first engagement portion <NUM> and second engagement portion <NUM> may abut or may be arranged flush with each other or may be spaced apart by a distance Δx in the locking state, as shown e.g. in <FIG>.

Referring to <FIG>, the locking system of <FIG> are shown more in detail. <FIG> illustrates the panels in locking state and <FIG> the unlocking state. As derivable from <FIG>, the displacement groove <NUM> comprises a bottom surface <NUM>, an upper surface <NUM> and a lower surface <NUM>, the lower surface <NUM> being parallel a displacement axis Ax of the tongue <NUM>. Thus, the tongue <NUM> may displace and/or linearly translate parallel the lower surface <NUM>. The displacement axis Ax may be parallel the plane Px of the lower surface <NUM>. As the tongue displaces in the locking direction and the unlocking direction respectively, the tongue <NUM> may be displaced along the displacement axis Ax. The tongue <NUM> may be displaced against or along the lower surface <NUM> and/or upper surface <NUM> of the displacement groove <NUM>.

A normal Ny of the plane Px extends in a direction transverse the plane Px as shown in <FIG>.

In the locking state, the first portion <NUM> may be wedged between the upper surface <NUM> of the displacement groove <NUM> and a lower surface of the tongue groove <NUM>, as shown in <FIG>.

An upper surface and/or lower surface of the tongue <NUM> may be substantially planar, or planar.

The first portion <NUM> of the tongue <NUM> may extend essentially along the displacement axis Ax, and may optionally have a substantially constant thickness in the direction of the normal Ny.

As schematically shown in <FIG>, a dimension Dy in the direction of the normal Ny may be measured between the plane Px and the first portion <NUM>, such as an underside of the protruding tongue nose.

Dy may be measured in the unlocking groove <NUM> in unlocking state.

Dy may correspond at least to a maximum diameter Dmax of the elongated element <NUM>.

The dimension Dy in the direction of the normal Ny of the plane Px, between the lower surface <NUM> and the first portion <NUM>, may correspond at least to a dimension Dx along the displacement axis Ax between the first engagement portion <NUM> and an outermost point 31a of the tongue <NUM>.

As derivable from <FIG> illustrating the locking state, the dimension along the displacement axis Ax between the outermost tip point 31a of the tongue <NUM> and the outermost point of the second engagement portion <NUM>, is denoted Dax. By the outermost tip point 31a of the tongue <NUM> is meant in a direction away from the first edge <NUM> in a direction along the horizontal plane H. By outermost point of the second engagement portion <NUM> is meant in a direction away from the second edge <NUM> in a direction along the horizontal plane H. It follows that in order for the tongue <NUM> to obtain an unlocking state, i.e. such that the second engagement portion <NUM> and the tip point 31a do not overlap in a direction along the engagement direction E, the tongue <NUM> should to displace at least a distance Dax in the unlocking direction along the displacement axis Ax. When the second engagement portion <NUM> and the tip point 31a do not overlap, the tongue is in the unlocking position and the second edge <NUM> of the second panel <NUM> may be disassembled from the first panel <NUM> by means of a displacement of the second edge in a direction being opposite the engagement direction E, i.e. a vertical displacement. This means the first edge <NUM> and the second edge <NUM> may essentially not displace horizontally relative each other during the vertical displacement, as shown in <FIG>, in other words, the horizontal relationships between features of the first edge <NUM> and the second edge <NUM> may not change during the disassembling. Therefore, starting from the locking state shown in <FIG> and <FIG>, for unlocking the mechanical locking system it may suffice to displace the locking tongue <NUM> such that an outermost point of second engagement portion <NUM> and the outermost tip point 31a do not overlap in a direction along the engagement direction E when the first and second panel <NUM>, <NUM> are adjacent as shown in <FIG> and <FIG>.

In some embodiments, there may be no play in the horizontal plane H, between the second engagement portion <NUM> and the tip point 31a. As derivable from <FIG>, dimension Dax is indicated as being measured from approximately half the extent of the second engagement portion <NUM> in order to provide play dH, however if the tongue is to be displaced such that there is zero play, Dax may be measured as the shortest distance between along the displacement axis Ax between the outermost tip point 31a of the tongue <NUM> and the second engagement portion <NUM>, as illustrated in <FIG>.

Consequently, a minimum cross-sectional diameter Dmin of the elongated element <NUM> may displace the tongue <NUM> at least the distance Dax along the displacement axis Ax, i.e. in the unlocking direction.

Accordingly, the unlocking groove <NUM> may be configured such that the tongue <NUM> is displaced in the unlocking direction a distance Dax in response to receiving an elongated element <NUM> of diameter Di, which may be a constant cross-sectional diameter, such that the tongue <NUM> assumes the unlocking state.

In particular, in the locking state, the distance Δx between the first engagement portion <NUM> and the second engagement portion <NUM> may be configured such that the tongue <NUM> is displaced in the unlocking direction along the displacement axis Ax a distance Dax in response to receiving an elongated element <NUM> of diameter Di, which may be constant cross-sectional diameter. The distance Δx may be measured along the plane H.

More in particular, the locking groove <NUM> may be configured such that when the distance between the first engagement portion <NUM> and the second engagement portion <NUM> essentially equals the diameter Di of the elongated element <NUM>, the tongue has been caused displace the distance Dax along the displacement axis Ax in response to the unlocking groove <NUM> receiving of the elongated element <NUM>.

In the locking state, a dimension along the displacement axis Ax between the first engagement portion <NUM> and an outermost point of the second engagement portion <NUM> may be greater than Dx.

The displacement groove <NUM> may be inclined by an angle φ relative the plane of the panels, such as the first panel <NUM> as shown in <FIG>. Thus, the displacement axis Ax and the plane of the lower surface Px are inclined in respect of the plane H, such as a horizontal plane. An upper surface <NUM> of the panel <NUM> and/or a lower surface <NUM> of the panel <NUM> may be parallel the plane H. This entails that as the tongue <NUM> translates along the displacement axis Ax there may be a certain ratio between downwards movement and sideways movement of the tongue <NUM>. For example, the tongue may be displaced the distance Dax in the displacement direction Ax; the sideways movement, typically horizontal, of the tongue <NUM> then corresponds to Dax*cosine(φ), and the downwards movement corresponds to the Dax*sine(φ). It follows that Di is preferably equal to or greater than the sum of Δx and Dax*cosine(φ), optionally greater by a margin corresponding to the dimension of the play dH. In a non-limiting example, φ may be between <NUM>° and <NUM>°, such as between <NUM>° and <NUM>°, such as about <NUM>°, <NUM>° or <NUM>°.

In the locking state, the first portion <NUM> of the tongue <NUM> may be configured to protrude from the displacement groove <NUM> and/or from the first edge <NUM> a distance along a direction in the H plane equal to or less than the cross-sectional width Di of the elongated element <NUM>.

In the locking state, the first portion <NUM> of the tongue <NUM>, such as the outermost point 31a, may be configured to protrude from the displacement groove <NUM> and/or from the first edge <NUM> a distance along a direction in the H plane equal to or less than the distance between a lower surface <NUM> of the displacement groove <NUM> and the first portion <NUM> in the direction of the normal Ny.

The unlocking groove <NUM> may be disposed at least partially between the tongue groove <NUM> and a lower surface <NUM> of the displacement groove <NUM>.

The second engagement portion <NUM> may extend at least at a mid-point between the first portion <NUM> of the tongue <NUM> and the plane Px of the lower surface <NUM> of the displacement groove <NUM>, preferably the second engagement portion <NUM> extends at least to the plane Px of the lower surface <NUM>.

The extension of the second engagement portion <NUM> in the normal direction Ny may be greater than the corresponding extension of the first engagement portion <NUM>.

The second engagement portion <NUM> may extend along or inside the vertical plane V.

The second engagement portion <NUM> may be stationary during displacement of the tongue <NUM> along the displacement axis Ax in the unlocking direction.

The unlocking groove <NUM> may be configured such that insertion of the elongated element <NUM> therein urges the unlocking groove <NUM> to expand by means applying force on the first engagement portion <NUM> in the unlocking direction.

The first portion <NUM> of the tongue <NUM> may comprise an outer and upper portion of the tongue <NUM> facing in a direction towards the upper surface <NUM> of the displacement groove <NUM>. The second portion <NUM> of the tongue <NUM> may comprise an outer and preferably lower portion of the tongue <NUM> facing in a direction towards the lower surface <NUM> of displacement groove <NUM>.

The elongated element <NUM> may have a longitudinal length corresponding to at least the length of the first <NUM> and/or second edge <NUM>, such as a respective short edge of the first <NUM> and/or second panel <NUM>. Alternatively, the elongated element <NUM> may have a longitudinal length corresponding to at least the length of the tongue <NUM> in the longitudinal direction L thereof, as indicated in <FIG>.

The locking groove <NUM> may form a needle bearing with the elongated element <NUM> in the unlocking state and may thus act as a needle bearing during disassembling of the panels in a direction opposite the engagement direction, typically vertical and upwards movement of the second panel <NUM> as shown in <FIG>.

The diameter of the elongated element <NUM> may be in the range of <NUM> to <NUM>, such as <NUM> to <NUM>, preferably about <NUM>.

The thickness of the panels <NUM>, <NUM> may be in the range of about <NUM> to about <NUM>, and preferably in the range of about <NUM> to about <NUM>.

The mechanical locking system comprises a first locking strip <NUM>, at the first or the second edge <NUM>, <NUM>, provided with a first locking element <NUM> configured to cooperate for horizontal locking with a first locking groove <NUM> at the other of the first <NUM> or second edge <NUM>.

<FIG> shows a cross section of a third edge <NUM> of the first panel <NUM> and a fourth edge <NUM> of a third panel <NUM>. The mechanical locking system at the third <NUM> and the fourth edge <NUM> comprises a second tongue <NUM> at the fourth edge <NUM> configured to cooperate for vertical locking with a second tongue groove <NUM> at the third edge <NUM>. The third edge <NUM> is provided with a protruding second locking strip <NUM> with a second locking element <NUM> configured to cooperate for horizontal locking with a second locking groove <NUM> at the fourth edge <NUM>. A second upper surface <NUM> of the second locking strip <NUM> is in contact with a lower surface of the second tongue <NUM> for locking in the vertical direction. The shown mechanical locking system at the third <NUM> and the fourth edge <NUM> is configured to be locked by an angling motion. The second upper surface <NUM> is positioned in a horizontal plane <NUM>. The embodiment in <FIG> is exemplary, other mechanical locking systems are conceivable at the third edge <NUM> and the forth edge <NUM>.

An upper surface <NUM> of the first locking strip <NUM> may be provided in a same plane <NUM> as an upper surface <NUM> of the second locking strip <NUM>.

The mechanical locking system at the third <NUM> and the fourth edge <NUM> may be configured to be assembled by an angling motion, such as a pivoting displacement about the fourth edge <NUM>.

The mechanical locking system at the first <NUM> and the second edge <NUM> may be configured to be assembled by a vertical motion.

The mechanical locking system at the first <NUM> and the second edge <NUM> may be configured to be assembled by a vertical motion, such as a vertical motion of the second edge <NUM> of the second panel <NUM> in the engagement direction E (see <FIG>) relative the first panel <NUM>.

The panels may be floorboards comprising a wood fibre-based core, such as HDF, or a core comprising thermoplastic, such as PVC.

The tongue <NUM> may comprise a chamfered end portion <NUM> as illustrated in <FIG>. The end portion <NUM> may be a longitudinal L end portion. In particular, the second portion <NUM> of the tongue <NUM> may comprise a chamfered end portion <NUM> forming a guiding surface <NUM> extending in the longitudinal and transverse direction of the tongue <NUM>. The second portion <NUM> of the tongue <NUM> may have a longitudinal L edge and a transverse edge as shown in <FIG>. A transition between the longitudinal edge and the transverse edge of the second portion <NUM> and/or a corner of the second portion <NUM> between the longitudinal edge and the transverse edge of the tongue <NUM> may comprise the chamfered end portion <NUM>. Thereby forming the guiding surface <NUM> extending in the longitudinal and transverse direction of the tongue <NUM>.

The guiding surface <NUM> may be configured to guide the elongated element <NUM> in the transverse T direction of the tongue <NUM> as the elongated element <NUM> is inserted in the unlocking groove <NUM> in a longitudinal direction of the tongue <NUM>.

As also shown in <FIG>, the tongue <NUM> may comprise biasing means <NUM> configured to bias the tongue <NUM> to displace along the displacement axis Ax in the locking direction. The biasing means <NUM> may be in the form of resilient feathers which may be formed integrally with the tongue <NUM>. The biasing means <NUM> may be configured to abut at least the bottom surface <NUM> of the displacement groove <NUM>.

As shown in <FIG>, the second edge <NUM> may comprise a chamfered edge portion <NUM>' for guiding the elongated element <NUM> in the longitudinal L direction of the panel <NUM> towards the unlocking groove <NUM>.

The panel <NUM>, <NUM> may have a longitudinal L edge and a transverse edge as shown in <FIG>. A transition between the second edge <NUM>, <NUM> and the third edge <NUM>, <NUM> and/or a corner between the second edge <NUM>, <NUM> and the third edge <NUM>, <NUM> may comprise the chamfered end portion <NUM>. Thereby forming the guiding surface <NUM>' extending in the longitudinal L and transverse T direction of the panel <NUM>, <NUM>.

In one embodiment shown in <FIG> and <FIG>, an embodiment of the inventive concept is configured to be applied in panels intended to be arranged in a herringbone pattern.

In a non-limiting example, such herringbone pattern may comprise two types of panels. An A-type panel and a B-type panel. The A-type panel and the B-type panel may mirror each other and/or be counter images of each other, as shown in <FIG> where <FIG> shows an A-type panel and <FIG> shows a B-type panel.

The A-type panel and the B-type panel may each comprise a short edge A11, A12, B11, B12 and a long edge A13, A14, B13, B14, wherein a long edge, such as A14, B14 may comprise a shape corresponding to the first edge <NUM> of the first panel <NUM> as explained above, for example in relation to <FIG>. A short side edge, such as A12, B12 may be edges corresponding to the second edge <NUM> as explained in relation to <FIG>. However, only a portion of the long edge, such as long edges A14, B14, comprises the displaceable tongue <NUM>, as illustrated in <FIG> and <FIG>.

One of the respective short sides of panel A and B, such as A11 and B11 or A12 and B12 may comprise an edge corresponding to the third edge <NUM> as explained with reference to <FIG> and the other edge may correspond to that of the fourth edge <NUM> as explained with reference to <FIG>.

A further long side, such as A13 and/or B13 may comprise a shape corresponding the fourth <NUM> edge as explained with reference to <FIG> such that the tongue <NUM> of a panel, such as panel A' or B' is received in the displacement groove <NUM> of the adjacent panel, such as panel A or B, as shown in <FIG>. It follows for example that panel B' may be assembled in locking position with panel A by means of vertical displacement of the second edge B12' i.e. the short side of panel B' relative the fourth edge A14, i.e. the long side of panel A.

It is thereby achieved that the herringbone pattern can be laid in part by means of vertical engagement to form a braid. It is further achieved that panels of the herringbone pattern may be disengaged by rotation and/or vertically instead of lateral sliding. This vastly facilitates ease of both assembling and disassembling of the floating floor.

In a non-limiting example, a herringbone pattern, such as the one shown in <FIG>, may be disassembled by means of a method comprising one or more of: providing the elongated element <NUM>; inserting the elongated element <NUM> in a first unlocking groove, such as <NUM>", between a second edge, such as B12', of a first panel, such as B', and a fourth edge, such as A14, of an adjacent second panel, such as A, to thereby vertically unlock the second edge of the first panel and the fourth edge of the second panel; pivoting or angling the said first panel to thereby horizontally unlock a third edge, such as B13', of the first panel and a fourth edge, such as B14, of an adjacent third panel, such as B; removing the first panel;
inserting the elongated element <NUM> in a second unlocking groove, such as <NUM>‴ between a second edge, such as A12, of the second panel and a fourth edge, such as B14, of the third panel to thereby vertically unlock the second edge of the second panel and the fourth edge of the third panel; removing the second panel.

<FIG> shows a perspective view of a device <NUM> for disassembling assembled building panels, such as the building panels shown in <FIG>. The device of <FIG> may be particularly suitable for disassembling building panels assembled to form a herringbone pattern, such as by means of the mechanical locking system of the first panel <NUM> and the second panel <NUM> as explained in relation to <FIG>, <FIG>.

<FIG> shows a side view of the positioning element <NUM> according to an embodiment of the inventive concept.

The positioning element <NUM> may comprise visual indication means <NUM>, such as a text and/or sign indicating an intended orientation of the positioning element in the displacement groove. The visual indication means may facilitate ease of use. The visual indication means may facilitate proper function of the device during use.

<FIG> shows another side view of the embodiment of <FIG>. The positioning element may comprise a through-hole <NUM>, extending from one side to an opposite side of the positioning element, preferably in a longitudinal direction of the positioning element.

<FIG> shows a perspective view of the embodiment of <FIG>.

<FIG> shows a cross view of a positioning element arranged in a displacement groove of a building panel <NUM>, which may be a Type-A or Type-B panel, according to an embodiment of the inventive concept. For ease or explaining the inventive concept, the elongated element <NUM> has been omitted in <FIG>, however, typically the elongated element may be arranged in the through-hole <NUM> of the positioning element <NUM>. As derivable from <FIG>, the positioning element may facilitate a centre axis 70x of the elongated element is positioned at a predetermined position when the positioning device is arranged in the displacement groove <NUM>. Preferably, when the positioning element is arranged in the displacement groove, an opening of the through-hole may be arranged adjacent an opening of the unlocking groove <NUM>, <NUM>", <NUM>"'.

Preferably, when the positioning element is arranged in the displacement groove, an opening of the through-hole may be arranged adjacent the second portion <NUM> of the locking tongue <NUM>.

Preferably, when the positioning element is arranged in the displacement groove, at least a portion of the through-hole may be aligned with the unlocking groove.

Preferably, when the positioning element is arranged in the displacement groove, at least a portion of an opening of the through-hole may be arranged adjacent the guiding surface <NUM>.

Preferably, when the positioning element is arranged in the displacement groove, at least a portion of the through-hole may be may be aligned with the guiding surface <NUM>.

The positioning element may facilitate a centre axis 70x of the elongated element is positioned at a predetermined distance from the bottom surface <NUM> of the displacement groove, preferably also at a predetermined distance from the lower surface <NUM> of the displacement groove, optionally also at a predetermined distance from the upper surface <NUM> of the displacement groove <NUM>, as illustrated in <FIG>.

<FIG> schematically illustrate a method of disassembling assembled building panels, according to an embodiment of the inventive concept.

<FIG> shows two assembled building panels, such as the panel A, which may correspond to the second panel <NUM>, and having second edge <NUM>. <FIG> also shows the device of <FIG> arranged in a displacement groove of one of panel B, which may correspond to the first panel <NUM> and having a first edge <NUM>.

<FIG> shows at least a portion of the elongated element <NUM> of the device <NUM> of <FIG> having been inserted in an unlocking groove <NUM>, <NUM>", <NUM>‴ shown in <FIG> to thereby displace the locking tongue in the unlocking direction to obtain the unlocking position or state. Consequently, there may be provided horizontal play between the first portion <NUM> of the locking tongue <NUM> and the engagement portion <NUM> of the second edge <NUM> of the second panel, whereby the second panel <NUM> may be displaced vertically, hence whereby the second panel <NUM> is vertically unlocked from the first panel <NUM>.

<FIG> shows a first and second building panel being disassembled by means of a vertical displacement of a second edge <NUM> of the second panel <NUM> relative a first edge <NUM> of a first panel <NUM>.

Claim 1:
A set of essentially identical panels (<NUM>, <NUM>), such as building panels, provided with a mechanical locking system comprising:
a displaceable tongue (<NUM>) arranged in a displacement groove (<NUM>) having a first opening at a first edge (<NUM>) of a first panel (<NUM>), said tongue (<NUM>) being configured to be displaced in said displacement groove (<NUM>) along a displacement axis (Ax) to attain a locking state wherein a first portion (<NUM>) of the tongue (<NUM>) cooperates with a first tongue groove (<NUM>) having a second opening at a second edge (<NUM>) of an adjacent second panel (<NUM>), for vertical locking of the first and the second edge (<NUM>, <NUM>); and
wherein a second portion (<NUM>) of said tongue (<NUM>) is configured to cooperate with said second edge (<NUM>) of said adjacent second panel (<NUM>) via an elongated element (<NUM>) for vertical unlocking of the first and the second edge (<NUM>, <NUM>) wherein a first engagement portion (<NUM>) of the second portion (<NUM>) is configured to engage with the elongated element (<NUM>) and delimits an unlocking groove (<NUM>) configured to receive the elongated element (<NUM>) such as to cause the tongue (<NUM>) to be displaced along the displacement axis (Ax) to attain an unlocking state for said vertical unlocking of the first (<NUM>) and the second edge (<NUM>), characterized in that a second engagement portion (<NUM>) of the second edge (<NUM>) is configured to engage with the elongated element (<NUM>) and delimits the unlocking groove (<NUM>, <NUM>", <NUM>"'), and that said second engagement portion (<NUM>) is provided externally of said first tongue groove (<NUM>).