FIELD OF THE INVENTION

The invention is in the field of a wood joint to be applied in furniture and the like, to a method of producing a piece of furniture comprising at least two plates, and to a piece of furniture comprising said wood joint. The method involves a computer controlled nesting machine or the like.

BACKGROUND OF THE INVENTION

The present invention can make use of a Computer numerical controlled (CNC) machine, wherein operation of the machine and machine tools is automated. A computer executes a sequence of machine control commands which is provided to the computer by an algorithm or the like. Also a change of machine tools, such as from a cutting to a drilling part, can be fully automated.

As such a series of parts can be formed, starting from one or more single elements, such as a plate suited for furniture.

The dimensions of a part (in the series of parts} can be de fined using computer-aided design (CAD) software. As mentioned above the design can then be translated into manufacturing directives by computer-aided manufacturing (CAM) software. The resulting directives can be transformed into specific commands necessary for a particular machine to produce the component, such as cutting away a section or drilling a slit.

Since forming a part can require use of a number (typically a multitude) of different operational tools, such as drills, saws, and cutters, machines often combine these multiple tools. In other installations, a number of different machines are used with an external controller and human or robotic operators that move the component from machine to machine.

The CNC machine is preferably a nesting machine. Nesting refers to a process of laying out cutting patterns with a pri mary goal to minimize raw material waste. Examples include manufacturing parts from flat raw material such as sheet metal, a wooden plate, a wood composite material, medium den sity fibre plate, plywood, synthetic material, and combinations thereof, such as Trespa®. To minimize waste of raw material produced during cutting, similar to the CNC machines nesting software is used. The software analyses the geometry of parts to be produced and optimizes production of ae required quantity of parts, while minimizing raw material being wasted. The present invention relates primarily to rectangular nesting, though it is equally applicable to geometries having an irregular or odd shape. Nesting software typically takes into account limitations and features of the machining technology in use, such as that no machining can take place where the raw material is clamped into place, as well as material characteristics, such as defects on material that must be discarded.

In production more and more use is made of these cnc nesting machines. As mentioned an entire plate is provided in a gross size and sucked in by means of vacuum. The parts of furniture are then milled out, whereby the parts preferably lie against each other as close to one and another as possible in order to provide maximum efficiency and minimal contamina tion of the machine.

In prior art furniture and wood construction dowels may be used. However, for drilling a hole the furniture panels need to be much further apart. A recess is then milled having a size of a drilling unit, and subsequently a hole is drilled laterally for this traditional dowel with the drilling unit. Apart from the additional processing, the lower efficiency and the pollution of the machine, an aggregate is also required.

One may only pre-drill the sidewalls of the panels and then screw the panels together. Such is however difficult to auto mate, if not impossible. Pre-drilling is also done in combina tion with the above dowel or the below Lamello connection.

In an alternative Lamello has brought the Clamex series (WO 2018/028911 A1 and US 2017/0114812 A2 ) on the market. However the Clamex requires a space between the (furniture) panels to be formed on a CNC or nesting machine of at least 110 mm. In addition an aggregate or a 5-axis machine is also required for making the Clamex connector, adding complexity to production. The efficiency is therefore low and a lot of waste is gener ated. From an economic point of view the Clamex series cost price of € 0.55-€ 0.70 is also not attractive.

In an alternative Lamello provides the Cabineo connector

(DE 10 2016 202 450 A1 ) which can also be used in the nesting, however. After assembling panels it is however in sight and is difficult to assemble, hence no industrial solution.

Incidentally reference can be made to DE 295 03 533 Ul, DE 43 20 164 Al, a video of Masterwood Deutschland GmbH (Nesting mit lamella Clamex Schrankverbindern mit Montage", 2017-4-11) , which relates to the above Clamex, and EP 0 898 086 A2, which latter document shows an almost complete sphere and a trapezium shaped part, of which the seems to be introduced from a side of a furniture part through a cylindrical opening. DE 295 03 533 Ul typically shows a three-piece connector, having two circular segments 8 and one rectangular element 5, which ele ments are not in the same plane and are not formed as one piece (fig. 1, claim 1) . A similar argument holds for DE 43 20 164 Al (fig. 2) showing two elements, with two or more curved sections in one element, and two or more recesses for receiv ing the curved sections in another element.

The present invention therefore relates to an improved wood joint, a method of producing furniture, and a piece of furni ture obtainable by said method, which overcome one or more of the above disadvantages, without jeopardizing functionality and advantages.

SUMMARY OF THE INVENTION

The present invention relates in a first aspect to a wood joint 10 for furniture comprising a circle segment 11 with a radius r, a width d, and length l _c , wherein the radius r is from 20-40 mm, preferably from 30-35 mm, a rectangular seg ment 12 with a width w and length l _r , wherein the length l _c of the circle segment is smaller than the length l _r , with a thickness t from 4-10 mm, preferably 5-8 mm, such as 6-6.5 mm. The present wood joint is referred to as Fixchip®. The Fixchip connector or joint is a new connector that is unique, as by using e.g. mechanical (CNC) machining the necessary recesses and slits can be produced with a vertical spindle. No further aggregates or drilling units are required. The FixChip provides a firm construction allowing no further movement of construction parts relative to one and another, contrary to e.g. the above prior art joints. It can be used both vertically and horizontally, and laterally no more than 38 mm space is re quired thereby reducing waste. After assembly the present joint is not visible. The Fixchip can ensure a definitive breakthrough of the use of a nesting machine, as the produc tion time drastically decreases (about 20%) , the yield goes up, less waste is formed and contamination of the machine is minimized. It is also more pure because as all operations can be performed with one and the same spindle; such has a further advantage that a more accurate reference point can be used, for determining a position of the spindle relative thereto; in fact the reference point may be regarded as an "absolute" origin point. This makes the Fixchip also interesting for traditional machines. The Fixchip may be in various forms, such as Fixchip that can be glued, and a Fixchip that can be firmly attached by impact (such as by a hammer) and therefore does not need an adhesive.

Constructively, tests have to be done with regard to ma terial. The Fixchip glue variant may have a larger glue sur face than the traditional dowel. In addition no remainders of glue are found, especially in the corners at the transition from the circular segment to the rectangular element. A pre ferred material is polymeric, such as plastic. It is noted that adhesion of a traditional wood adhesive with the plastic could have a negative influence on adhesive strength. By providing grooves the adhesive connection is found to be suf ficiently strong. For the Fixchip impact variant hooks may be provided which only allow release of the connector by force. A big advantage of the Fixchip impact variant is that no pressing time and screws are required when assembling the furni ture. This offers a perspective for do-it-yourself furniture.

In a second aspect the present invention relates to a piece of furniture comprising at least two plates 20, a first plate 20a having at least two slits 21 provided in a top side thereof, each slit having a depth substantially equal to a width w of the rectangular segment 12 of the wood joint 10, a length equal to the length l _r of the wood joint 10, and a width substantially equal to the thickness t of the wood joint, a second plate 20b, having at least two recesses 22 provided at a side thereof, each recess having a depth substantially equal to a width d of the circular segment 11 of the wood joint 10, a length equal to the length l _c of the wood joint 10, and a width substantially equal to the thickness t of the wood joint, and at least two wood joints 10, wherein the first plate 20a and second plate 20 are joined under an angle of 90 degrees by the wood joints 10. It is noted that if a length of a plate is relatively small, such as smaller than 20 cm, only one slit and recess can be provided. Examples of furniture are cupboards, kitchen furniture, etc.

In a third aspect the present invention relates to a method of producing the present piece of furniture, comprising providing a computer controlled CNC nesting machine, providing an algorithm for cutting and drilling, providing a plate, re moving at least 35 mm of plate material in between plate sec tions, providing at least two recesses at at least one side of a plate section with a radius of 35 mm, a height t, and a width d, and providing at least two slits at a top side of a plate section.

Thereby the present invention provides a solution to one or more of the above-mentioned problems.

Advantages of the present invention are detailed throughout the description.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates in a first aspect to a wood joint according to claim 1.

In an exemplary embodiment the present wood joint may comprise at least one recess 17 for distributing an adhesive.

In an exemplary embodiment the present wood joint is at least partly provided with regular grooves, such as grooves of 0.2-2 mm, preferably 0.3-1.5 m , such as 0.4-0.8 mm.

In an exemplary embodiment of the present wood joint hooks are provided at a surface thereof.

In an exemplary embodiment of the present wood joint at least one side is rounded, preferably two small and opposite sides 18 of the rectangular segment and the circular side 19 of the circular segment.

In an exemplary embodiment of the present wood joint w is 10-15 m , preferably 12-13 mm,

In an exemplary embodiment of the present wood joint d is 10-15 , preferably 12-13 mm,

In an exemplary embodiment of the present wood joint l _r is 30-50 mm, preferably 38-42 nun.

In an exemplary embodiment of the present wood joint the joint is made from a metal, such as stainless steel, alumin ium, brass, copper, from wood, from a polymer, and combinations thereof.

In an exemplary embodiment of the present furniture each plate 20a comprises one slit 21 per 10-40 cm, and wherein each plate 20b comprises one recess 22 per 10-40 cm. As mentioned above if a plate 20a or 20b is relatively small, such as smaller than 20 cm, e.g. 10 cm, only one recess and slit are provided respectively.

The invention is further detailed by the accompanying figures and examples, which are exemplary and explanatory of nature and are not limiting the scope of the invention. To the person skilled in the art it may be clear that many variants, being obvious or not, may be conceivable falling within the scope of protection, defined by the present claims .

SUMMARY OF THE FIGURES

Figure la-h show exemplary embodiments of the present FixChip .

Figure 2a-c show panels and a piece of furniture.

Figure 3 shows planned operations on a nesting machine.

DETAILED DESCRIPTION OF THE FIGURES

Figure la shows the present wood joint 10 with circular segment 11 and rectangular element 12 schematically. The cir cular segment has a radius r, a length l _c , and a width d, whereas the rectangular segment has a width w and a length l _r , l _r being larger then l _c . The thickness is about 8.5 m.

Fig. lb shows recesses 17 provided in both segments, for supporting distribution of an adhesive to be applied. Further a side 19 of the circular segment is indicated.

Fig. lc shows a side view of the FixChip, whereas fig. Id shows a front view and fig. le shows a perspective view. Fig.

If shows a top view with 5 recesses in the rectangular segment and also 5 grooves (albeit some having a small length} in the circular segment.

Fig. lg shows an example of the impact variant, provided with hooks or ridges. The left side can be used as an impact side. Fig. lh shows a side view thereof.

Fig. 2a shows a first panel 20a provided with slits 21 in a top side thereof, and fig. 2b a second panel 20b with recesses 20 provided in a (left) side thereof. Fig. 2c shows a piece of furniture 30 having a number of panels 20b and 20a, and joints 10 providing a firm construction.

Fig. 3 shows planned operations on a nesting machine and a schematically result thereof. Various panels 20a and 20b are formed. In between panels material is removed by a cutter with a radius of 35 mm. Slightly more material (36-40 mm, typically 38 m ) is removed, allowing free passage of the cutter. The cutter is used to make recesses 22 which resemble the circular segments 11 closely, having a width w and a radius r; the cut ter only enters panel 20b partly. Also recesses 21 are formed on a top side of panels 20a.

The figures are further detailed in the description and examples below.