SYSTEM

The idea relates to a jointing system, and a method for manufacturing a jointing system.

Background

In recent years, panels based on a core sandwiched between printable facing sheets have been commonly used to replace traditional board material, such as MDF or HDF. EP1714776A1 discloses a light-weight wood fiber based panel of the above mentioned sandwiched-type , wherein the flutes or channels forming the core are tilted in relation to the facing sheets. Such light-weight panels might for example be used as in-store displays or in furniture. In the manufacturing of such

products, the board often needs to be molded to provide a curved surface, or alternatively, several separate boards are nailed to each other in order to build up the display or furniture. A common in-store display for showing e.g.

electronic products is shown in fig. 1. Today, such a display is usually assembled before transported to the store. An assembled display, such as the one shown in fig. 1, is cumber and takes up a lot of space in the freight of the display to the store.

Summary of the invention

One object of this invention is to provide a jointing system for forming curves or corners in a board, such as a lightweight board, in an easy way.

The jointing system according to the invention comprises a first and a second board, or a first part and a second part of a board, adapted to be jointed at an angle to each other, preferably at an angle of about 90 degrees to each other. Each of said boards, or parts of a board, comprises a lightweight core formed as a three dimensional body presenting a first and a second face and four side surfaces connecting said first and second faces. At least one of said side surfaces of each board, or each part of a board, is miter cut to present a first mitered surface of a first board, or of a first part of a board, and a second mitered surface of a second board, or of a second part of a board, said first mitered surface being adapted to abut said second mitered surface for forming a miter joint. Each of the boards, or each part of a board, further comprises an aperture extending from the mitered surface parallel to the first and second face, in the

direction to the opposite side of the board. The system of the invention further comprises a first and a second insert adapted to be inserted into said apertures of the first and the second board, or of the first and the second parts of a board, which inserts comprise cavities. The system of the invention further comprises a corner connector. Said corner connector comprises a first leg being adapted to be inserted into the first aperture of the first board or of the first part of a board, and a second leg being adapted to be inserted into the second aperture of the second board or of the second part of a board for forming said miter joint.

The inventive system gives rise to stable corners or curves in displays, furniture, buildings and the like in an easy way. The invention makes it possible to transport flat boards, comprising the inserts, unassembled, which boards are easily assembled to provide corners or curves by use of the corner connector. This involves savings in time and in transportation costs. The inserts provide a stable reception for the legs of the corner connector, which stabilize the miter joint.

In one preferred embodiment, the lightweight core may comprise a wall structure defining a plurality of channels, each channel having a longitudinal axis intersecting the first face. Preferably, the channels intersect the first face at an angle (a) which is less than 90 degrees, preferably between 45 - 80 degrees. Such a structure gives rise to an exceptionally strong, but yet light-weighted board which is easy to handle. The tilted channels of the core in such a structure give rise to a larger surface for a facing sheet to be attached to, which in turn gives an even stronger material. Preferably, the core comprises fiber based material, such as paper or paper board .

The first and the second leg of the corner connector may be adapted to form an angle of between 85 - 90 ° to each other when the miter joint is formed. In this way, the boards, or the parts of a board, may form a right angle to each other when the system is assembled.

The legs of the corner connector may be connected to each other by a hinge connection. The hinge connection may enable the corner connector to alter between an open position, with the legs forming an angle of about 180° to each other, and a closed position, with the legs forming an angle of about 90° to each other. The hinge connection may further enable one of the legs of the corner connector to be folded back 270° from the closed position. In this way, the corner connector may form a compact unit at the freight thereof. The first leg of the corner connector may further comprise a female locking member and the second leg may comprise a male locking member complimentary to the female locking member in order to provide a stable lock of the corner connector in the closed position, when forming the miter joint.

In another embodiment of the corner connector, the connector may be stiff. In this embodiment, the first leg and the second leg may form an angle of < 90 ° to each other, preferably an angle of between 85 - 89 to each other, or between 87 - 89°. This gives rise to a tension, which stabilizes the lock of the boards or parts of the boards in a position where the boards or parts form a right angle to each other. The first and/or second leg of the corner connector may taper towards their free ends. Moreover, the circumference of the first and/or second leg of the corner connector in the vicinity of their common basis may exceed the circumference of the aperture of the insert. This contributes to the stabilization of the lock of the corner. The corner connector and the insert may further be made of the same material, preferably of plastics. This stabilizes the lock even further, since it creates a friction between the inserts and the legs of the corner connector.

In one embodiment of the invention, the jointing system comprises a first and a second board, which boards comprise a first and a second facing sheet laminated on the first and second faces of said first and second cores. This embodiment is especially advantageous when handling large boards to be assembled into large structures. The stiff corner connector described above may advantageously be used to lock the boards according to this embodiment.

In another embodiment of the invention, the jointing system comprises a first part and a second part of a board, which first part and second part are connected to each other by a hinge connection comprising, or being formed of, a first facing sheet laminated on the cores of the first and the second part of the board. This embodiment is especially advantageous when, e.g., smaller furniture or displays are to be formed. According to this embodiment, a single board, provided with at least one v-cut, may be used to form the whole furniture or display. The v-cut may be 90°, thus the miter-surfaces formed by the v-cut may form an angle of 45° to the facing sheet, and thus an angle of 90° to each other. The hinge connection allows the parts of the board to rotate from a flat position to a position where a substantially right angle is formed between the parts when the miter joint is formed. The hinge connection may further allow one of the parts of the board to rotate 270° in relation to the other from the position where a substantially right angle is formed between the parts. Thus, one of the parts of the board may be folded back so that the rear sides of the parts of the board, i.e. the first faces of the parts of the board, which are covered by the facing sheet, are abutting each other. In this way, the jointing system may form a compact unit at the freight thereof. The facing sheet forming the hinge connection partly covers the corner or curvature when the miter joint is formed. This contributes to a nice appearance. The facing sheet uniting the boards is preferably made of a strong material, such as polyester, Teflon, carbon fibers or nylon. The hinged corner connector described above may advantageously be used to form the lock in this embodiment.

The invention further relates to a method of manufacturing a jointing system, said method comprising the steps of;

providing a light weight core formed as a three dimensional body presenting a first and a second face and four side surfaces connecting said first and second faces,

providing said core with at least one groove with a

predetermined depth in the first face,

inserting an insert comprising a cavity into the at least one groove

laminating at least one facing sheet onto the first face and/or the second face of the core,

at least partly cutting said core with the at least one facing sheet at a cutting angle of about 45 ⁰ to the first face and providing a corner connector comprising a first and a second leg, which first leg is adapted to be inserted into said cavity and said second leg is adapted to be inserted into a cavity of a second board, or of a second part of the board, in order to form a miter joint.

In accordance to the method of the invention, a jointing system for forming corners or curvatures of or in light-weight boards may be manufactured in an efficient way. The formation of a groove in the first face, into which groove an insert is inserted, prior to the step of laminating a facing sheet onto the core facilitates the insert of the insert in the board. Preferably, said grooves are formed as apertures in the core, i.e. the depth of the grooves correspond to the thickness of the core.

In one embodiment of the invention, the step of cutting comprises miter-cutting through the core and through the at least one facing sheet such that a first and a second board is formed. In this way, a jointing system for jointing two separate boards is formed. This embodiment is especially advantageous when large boards to be assembled into large structures are handled.

In another embodiment of the invention, the step of cutting comprises cutting the core such that a v-shaped cut is formed in the core, forming a first part and a second part of the core, hingedly connected by the at least one facing sheet. In this way, a jointing system comprising a first part and a second part of a board, which first part and second part are connected to each other by a hinge connection comprising, or being formed of, a first facing sheet laminated on the cores of the first and the second part of the board is formed. The v-cut may be 90°, thus the miter-surfaces formed by the v-cut may form an angle of 45° to the facing sheet, and thus an angle of 90° to each other.

Detailed description

The invention relates to a system for the formation of corners of light-weight boards. The invention enables boards to be transported plane to their usage destination where they can be easily assembled to form building structures comprising panels at an angle to each other. Moreover, the corners or curves formed by the system of the invention are very stable. The invention also aims at providing a method for manufacturing such a system in an efficient way.

In accordance with the invention, a first and a second light weight board, or a first and a second part of a board, are miter cut to provide a first and a second mitered surface. Preferably, said miter cut is provided by cutting the board at an angle of 45°. Thereafter, said first mitered surface is arranged to abut said second mitered surfaces for forming a miter joint. Said joint forms a 90° corner.

Said first and second light-weight board, or said first and second part of a board, comprises a lightweight core formed as a three dimensional body presenting a first and a second face and four side surfaces connecting said first and second faces. Said core may comprise a wall structure defining a plurality of channels, the end portion of the channels forming a first face. Preferably, the channels intersect the first face at an angle (a) which is less than 90 degrees, preferably between 45 - 80 degrees. The light weight board to be used in the present invention may e.g. be of the type described in the patent application EP1714776A1. The core is preferably made of wood fiber based material, such as paper or paper board. The jointing system of the present invention is especially

advantageous when used in combination with boards comprising such cores, since it provides stable corners or curvatures in such a material.

Facing sheets may be laminated onto the first and/or second face of the core. Said facing sheets may be a sheet of paper, cardboard laminate, sheet metal, wood veneer, polymer films, high or medium density fiberboard or sheets or other materials which is attachable to the core to provide a surface, which may be e.g. smooth, printable and/or water repellant. The invention will further be described by way of examples with reference to the figures of the accompanying drawings, in which :

Figure 1 shows a display of the prior art that can be

assembled by use of the present invention

Figure 2 shows a first and a second board of a jointing system according to a first example of the invention.

Figure 3 shows a first example of a corner connector according to the invention

Figure 4 shows an insert according to the invention

Figure 5 shows a board according to a second example of the invention

Figure 6 shows a second example of a corner connector

according to the invention

Figure 6a shows said second example of a corner connector with the legs in a closed and locked position.

Figure 6b shows said second example of a corner connector with the legs in a partly open position

Figure 6c shows a top view of said second example of a corner connector with the legs in a partly open position.

Figure 6d shows said second example of a corner connector with the legs in a folded back position

Figure 6e shows an end view of said second example of a corner connector with the legs in a folded back position.

Fig. 2 shows a first (1) and a second (2) board to be

assembled according to a first example of the invention. The first board (1) comprises a first miter surface (16) and the second board (2) comprises a second miter surface (17) adapted to abut the first miter surface (16) of the first board in order to form a miter joint. The first and second board (16, 17) comprises a lightweight core and a first and a second facing sheet laminated onto said core. The first board (1) comprises a first aperture (18) extending inwardly from the first miter surface (16), parallel to the facing sheets of the first board. The second board (2) comprises a second aperture (not shown) extending inwardly from the second miter surface (17) parallel to the facing sheets of the second board. A first and a second insert (30) are inserted into said first and second aperture (18) .

The insert (30) is shown in more details in fig. 4.

Preferably, the insert is in the form of a rectangular tube, comprising a tubular cavity (31), which tube is made of plastic .

In order to attach the first (1) and the second (2) boards to each other, a corner connector (40), such as the one shown in fig. 3, may be used. The corner connector (40) comprises a first leg (41) and a second leg (42) connected by a common basis (43), said first leg (41) and second leg (42) forming an angle, a, of about 89 ° to each other. The legs (41) and (42) taper towards their free ends. Moreover, the circumferences of the legs (41, 42) in the vicinity of their common basis (43) basis (43) exceeds the circumference of the aperture (31) of the insert ( 30 ) .

When the boards (1 and 2) shown in fig. 2 are to be assembled, the first leg (41) of the corner connector (40) shown in fig. 3 is inserted into the cavity (31) of the insert (30) of the first board (1), whereupon the second leg (2) is inserted into the cavity (31) of the insert (30) of the second board (2) . In this way, the boards (1 and 2) are locked in a position where the miter-cut surfaces (16 and 17) are facing each other. The lock is formed by the tension caused by the legs (41, 42) of the corner connector forming an angle of < 90° to each other as well as the tapered form of the legs.

Fig. 5 shows a board (10) to be assembled according to a second example of the invention. The board comprises a

lightweight core (13) of the above described type, and a first (14) and a second (15) facing sheet laminated onto said core (13). The board (10) comprises a first (11) and a second (12) part, formed by said board (10) being provided with a first v- cut (20) . Said first (11) and second (12) part is joined by said second facing sheet (15), which forms a hinge connection

(25) between the parts. Said hinge connection (25) allows the first part (11) of the board (10) to turn at least 90°, preferably 270°, in relation to said second part (12) of the board. Thus, the parts (11, 12) may be altered between a folded back position, wherein the rear sides of the parts, i.e. the faces covered by the facing sheet (15), abut, to a flat position as shown in fig. 5, and, finally, to a position wherein the parts form 90° to each other when the miter joint is formed. The v-cut provides the first part (11) with a first miter surface (16) and the second part (12) with a second miter surface (17), which second miter surface (17) is adapted to abut said first miter surface (16) when forming the miter joint. The first part of the board (11) comprises a first aperture (18) extending inwardly from the first miter surface

(16), parallel to the facing sheets. The second part (12) of the board comprises a second aperture (18') extending inwardly from the second miter surface (17) parallel to the facing sheets. A first and a second insert (30) are inserted into said first and second aperture (18, 18') . The insert is shown, separately from the board, in more details in fig. 4.

Preferably, the insert to be used in this second example is the one shown in fig. 4 and described in more details above.

In order to assemble the board (10) and form curves, the corner connector (50) shown in fig. 6 may be used. The corner connector shown in fig. 6, comprises a first leg (51) and a second leg (52) connected to each other in a hinge connection (53) . The hinge connection (53) allows the legs to rotate from a first, partly open, position, wherein the first leg (51) and the second leg (52) has an extension in the same plane (as shown in fig. 6b), to a second, closed, position wherein the legs (51 and 52) form an angle of 90° to each other (as shown in fig. 6a) . The hinge connection (53) further allows the legs to rotate 270° backward from the 90° position, to a third, open, folded back, position, where the outer surfaces of the legs are abutting each other (as shown in fig. 6e.) . The first leg (51) of the corner connector (50) comprises a first beveled surface (51') adapted to abut a second beveled surface (52') of the second leg (5) when the legs are in said second position. The second leg (52) comprises a male connector (55) in the form of a protrusion protruding from the second surface (52'). The first leg (51) comprises a female connector (54) in the form of a bore (54) extending inwardly from the first surface (51') and adapted to receive the male connector (55) when the legs are in said second position. The male connector (55) further comprises conically formed locking members (56) which are adapted to engage with complementary recesses (57) in the female connector (57) .

In the assembling of the board (10), the first leg (41) of the corner connector (40) is introduced in the cavity (31) of the first insert (30) of the first part of the board (11) and the second leg (42) is introduced in the cavity (31) of the second part of the board (12) . Thereafter, said first part (11) is bended towards the second part (12) whereby the board (10) is locked in a position where the miter-cut surfaces (16 and 17) are facing each other. The board (10) according to the example further comprises a second v-cut (21), forming a third part (23) of the board (10), attached to the second part (12) by a hinge connection (25'). Said third part (13) may, similarly to the first part (11), be rotated at least 90°, preferably 270°, in relation to said second part (12) so that the miter

surfaces of said second v-cut abut each other in a second miter joint. In this way, a display such as the one shown in fig. 1, may be assembled.

In the manufacturing of the board (10) shown in fig. 5, a lightweight core (13) is provided with grooves (22) with a predetermined depth in the first face of the core. The grooves may be formed as apertures in the core, i.e. with depths corresponding to the thickness of the core. This facilitates the removal of the core material when cutting the grooves. In the example shown in fig. 5, the core is provided with two grooves (22, 24) running from one of the short sides of the core (13) across the whole length of the core (13) to the opposite short side. However, the core (13) may alternatively be provided with shorter channels at the position where the v- cuts are to be formed. Thereafter, inserts (30) are inserted in the channels (22, 24) . The inserts may have a length (1) corresponding to the length of the channels (22, 24) .

Alternatively, several shorter inserts may be inserted in the channels (22, 24) at the position where the v-cuts are to be formed. After the inserts (30) have been inserted into the channels, the facing sheets (14, 15) are laminated on the core. The channels (22, 24) are shown as broken lines in fig. 5, to emphasize them being underneath the facing sheet (14) . Thereafter, the board (10) comprising the core, the inserts and the facing sheets, is provided with v~cuts (20, 21) . The v-cuts (20, 21) are cut in the board (10) such that a first (11), a second (12) and a third (23) part of the board are formed, connected at the rear side by the facing sheet (15) . The facing sheet (15) forms a hinge connection between the parts .