SE1950098A1 - Joining system for furniture parts - Google Patents

Abstract

A joining system for furniture parts is disclosed comprising a female coupling recess formed in a first furniture part, a male coupling tongue projecting from an adjoining second furniture part, said female coupling recess being adapted to receive the male coupling tongue, an upper guiding surface arranged on a first side of the female coupling recess on the first furniture part, a lower guiding surface arranged on a second side of the female coupling recess on the first furniture part, located opposite to said first side thereof, said lower guiding surface is configured to force the male coupling tongue to resiliently deflect whilst in engagement with said upper guiding surface upon further insertion thereof in a deflection movement towards said first side of the female coupling recess, until a first locking element of the male coupling tongue snaps together with a matching second locking element of the female coupling recess.

Description

JOINING SYSTEM FOR FURNITURE PARTS TECHNICAL FIELD The invention relates to a joining system for furniture parts, comprising a femalecoupling recess formed in a first furniture part. The female coupling recess isadapted to receive a male coupling tongue projecting from an adjoining secondfurniture part.

BACKGROUND ln the recent years the furniture industry is gradually replacing traditional fasteningand joining methods using nails and screw and nut joining elements with varioussnap-locking joining systems. This trend vastly facilitates installation of furnituresuch as for example book shelves, wardrobes and cupboards.

An example of such a joining system is described in US 9 714 672 (B2) where aset of panels includes a first panel having a first main plane and a second panelhaving a second main plane. The panels are provided with a mechanical lockingdevice for locking a first edge of the first panel to a second edge of the secondpanel. The mechanical locking device includes an edge section groove at the firstedge, wherein an edge section of the second edge is insertable into the edgesection groove. A flexible tongue is pre-fitted in an insertion groove provided in theedge section groove and cooperates with a tongue groove provided at the edgesection of the second panel. The complexity of the joining systems in the prior artis a problem that entails complicated and expensive manufacturing processes. Afurther problem with the prior art systems is lack of stability in certain loaddirection. ln some cases the lack of structural symmetry, results in insufficient sidestability, or bending resistance. Stability may be sufficient when subjected to aforce in one direction. lf subjected to a force in another direction, normally theopposite direction, the prior art joining systems may be weaker and eventually flex,deflect or bend in an undesired way. These uneven stability properties of the jointshave to be taken into account when designing a piece of furniture, whichpotentially limits available design options in the design process.

SUMMARY lt is an object of the invention to at least partly overcome one or more limitations ofthe prior art. ln particular, it is an object to provide and improved joining system forfurniture parts which is less complex to manufacture and which is more robust withan increased multi-directional side stability compared to existing joining systems. ln as first aspect of the invention, this is achieved by a joining system for furnitureparts comprising female coupling recess formed in a first furniture part, a malecoupling tongue projecting from an adjoining second furniture part, said femalecoupling recess being adapted to receive the male coupling tongue, said malecoupling tongue comprising a first locking element configured for a snap jointinterlocking engagement with a matching second locking element in said femalecoupling recess, the male coupling tongue being configured to be more flexiblethan the female coupling recess. The joining system comprises an upper guidingsurface arranged on a first side of the female coupling recess on the first furniturepart, forming an essentially non-resilient guide for the male coupling tongue uponinsertion thereof, limiting movement of said male coupling tongue in a directiontowards said first side of the female coupling recess. The joining systemcomprises a lower guiding surface arranged on a second side of the femalecoupling recess on the first furniture part, located opposite to said first sidethereof, said lower guiding surface is configured to force the male coupling tongueto resiliently deflect whilst in engagement with said upper guiding surface uponfurther insertion thereof in a deflection movement towards said first side of thefemale coupling recess, until the first locking element of the male coupling tonguesnaps together with the matching second locking element of the female couplingrecess. The lower guiding surface at its lowest end transitions into a lateral lockingsurface extending essentially parallelly to a longitudinal direction of the femalecoupling recess, said lateral locking surface is configured to exert a horizontalpressure on the male coupling tongue towards said first side of the femalecoupling recess, holding the first and second locking elements of the malecoupling tongue and the female coupling recess in engagement with each other ina joined state between the first furniture part and the second furniture part.

Having a lower guiding surface configured to force the male coupling tongue toresiliently deflect whilst in engagement with said upper guiding surface uponfurther insertion thereof in a deflection movement towards said first side of the female coupling recess, until the first Iocking element of the male coupling tonguesnaps together with the matching second Iocking element of the female couplingrecess, provides for a robust joining system with an increased multi-directionalside stability, while being less complex to manufacture.

Still other objectives, features, aspects and advantages of the invention willappear from the detailed description as well as from the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the invention will now be described, by way of example, withreference to the accompanying schematic drawings.

Fig.1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 shows a side view of a joining system according to an example ofthe disclosure, applied on an exemplifying basic furniture 90 degreecorner joint between two furniture parts. The figure shows the joiningsystem in a fullyjoined and locked position, wherein a male couplingtongue extending from one of the furniture parts is engaged in afemale coupling recess formed in the other furniture part. shows a side view similar to the one in Fig. 1, only here in a positionbefore the male coupling tongue of the second furniture part hasengaged the female coupling recess of the first furniture part. shows a further side view of the joining system in an intermediateinsertion position, wherein the male coupling tongue is resilientlydeflected to the left in the figure, immediately before finally snappinginto the final locked position as shown in Fig. 1. shows a similar side view as in Fig. 1.shows a further side view of the joining system in an intermediateinsertion position, wherein the male coupling tongue rests on an edge in the female coupling recess before further insertion. shows a side view of a cornerjoint of the joining system.

Fig. 7a shows a similar side view as in Fig. 2, albeit in an example where adetachable Iocking element is arranged on a core portion of the malecoupling tongue.

Fig. 7b shows a further side view where the male coupling tongue with itsdetachable Iocking element is arranged in an interlocked state withthe female coupling recess.

Fig. 7c shows a similar side view as in Fig. 7a but with the detachableIocking element removed from the male coupling tongue.

Fig. 8a shows a similar example as in Fig. 7a but in a perspective view.

Fig. 8b shows a similar side view as in Fig. 7b but with a groove in a bottomportion of the female coupling recess.

Fig. 9 shows a perspective view of the first and second furniture parts where detachment is accomplished by a sideways relativemovement thereof.

DETAILED DESCRIPTION Embodiments of the invention will now be described more fully hereinafter withreference to the accompanying drawings, in which some, but not all, embodimentsof the invention are shown. The invention may be embodied in many differentforms and should not be construed as limited to the embodiments set forth herein.

Fig. 1 is a schematic illustration of a joining system 1 for furniture parts 10, 20. Thejoining system 1 comprises a female coupling recess 30 formed in a first furniturepart 10, and a male coupling tongue 40 projecting from an adjoining secondfurniture part 20. The female coupling recess 30 is adapted to receive the malecoupling tongue 40, and the male coupling tongue 40 comprises a first Iockingelement 50 configured for a snap joint interlocking engagement with a matchingsecond Iocking element 60 in the female coupling recess 30. The male couplingtongue 40 is configured to be more flexible than the female coupling recess 30.

The material surrounding the female coupling recess 30 is thus more rigid than themale coupling tongue 40. The male coupling tongue 40 may be configured to beessentially resilient whereas the female coupling recess 30 is configured to beessentially rigid and non-resilient. An upper guiding surface 110 is arranged on afirst side 115 of the female coupling recess 30 on the first furniture part 10. Theupper guiding surface 110 forms an essentially rigid or non-resilient guide for themale coupling tongue 40 upon insertion thereof, limiting movement of the malecoupling tongue 40 in a direction towards the first side 115 of the female couplingrecess 30. The joining system 1 comprises a lower guiding surface 130 arrangedon a second side 116 of the female coupling recess 30 on the first furniture part10, located opposite to said first side 115 thereof. The lower guiding surface 130 isconfigured to force the male coupling tongue 40 to resiliently deflect whilst inengagement with the upper guiding surface 110 upon further insertion thereof in adeflection movement, as schematically illustrated in Fig. 3. The male couplingtongue 40 is deflected towards the first side 115 of the female coupling recess 30,until the first locking element 50 of the male coupling tongue 40 snaps togetherwith the matching second locking element 60 of the female coupling recess 30, i.e.to assume the joined state shown in Fig. 1. The first locking element 60 maycomprise an integral protrusion 60 integrally formed in the male coupling tongue40. The protrusion 60 may extend in a direction essentially perpendicular to alongitudinal direction 245 in which the male coupling tongue 40 extends. Thesecond locking element 60 may comprise a recess 60 for receiving the protrusion60.

The lower guiding surface 130 at its lowest end 160 transitions into a laterallocking surface 170 extending essentially parallelly to a longitudinal direction of thefemale coupling recess 30. The lateral locking surface 170 is configured to exert ahorizontal pressure (P) on the male coupling tongue 40 towards the first side 115of the female coupling recess 30, as schematically illustrated in Fig. 1. Thehorizontal pressure (P) holds the first and second locking elements 50, 60 of themale coupling tongue 40 and the female coupling recess 30 in engagement witheach other in a joined state between the first furniture part 10 and the secondfurniture part 20. The first and second furniture parts 10, 20, may thus be joined ata 90 degree angle as illustrated in e.g. Fig. 1. lt should be understood that the firstand second furniture parts 10, 20, may be joined at different angles, i.e. oblique oracute angles, besides from the perpendicular angle as illustrated in the example ofFig. 1.

Having a lower guiding surface 130 configured to force the male coupling tongue40 to resiliently deflect whilst in engagement with the upper guiding surface 110upon further insertion of the male coupling tongue 40 in a deflection movementtowards the first side 115 of the female coupling recess 30, until the first lockingelement 50 snaps together with the matching second locking element 60, providesfor a robust joining system 1 with an increased multi-directional side stability, whilebeing less complex to manufacture. A further increased stability and increasedstrength in the interlocked state of the first and second furniture parts 10, 20, isprovided for when having the first locking element 60 comprising an integralprotrusion 60 integrally formed in the male coupling tongue 40. E.g. a drawback ofprior art joining system is that a separate flexible polymer tongue is typicallyrequired for the interlocking of the furniture parts, which has to be pre-fitted duringmanufacture. This may increase the complexity of the production line andmanufacturing process as well as the joining system as such becomes moreexpensive. The throughput of the production line in mass production may also bemore limited. Thus, in addition to providing for a more robust and strongerjoiningsystem 1 which can absorb greater force loads in more directions - due to itssingle-piece integrated construction - the manufacturing thereof is also facilitated.The furniture parts 10, 20, may correspond to various parts of pieces of differentfurniture items to be assembled together utilizing the joining system 1, such asdrawers, wardrobes, shelves, desks, cabinets, etc.

The lower guiding surface 130 may be arranged at an apex formed at the joiningedge of the lateral locking surface 170 and an inclined surface 48 at the secondside 116 of the female coupling recess 30, as illustrated in Fig. 2. At least part ofthe aforementioned inclined surface 48 may form the lower guiding surface 130.E.g. as the male coupling tongue 40 is inserted into the female coupling recess 30,a lower portion of the male coupling tongue 40 may be initially guided by theinclined surface 48 to the position shown in Fig. 5. As a force is applied on themale coupling tongue 40 for continued insertion thereof, the reaction force towardsthe male coupling tongue 40 for deflection thereof becomes more concentrated tothe apex of the lateral locking surface 170 and the inclined surface 48, i.e. wherethe guiding surface 130 is indicated in Fig. 3.

The lower guiding surface 130 may be configured to force the male couplingtongue 40 to resiliently deflect whilst in engagement with said upper guiding surface 110 upon further insertion thereof in a curved J-shaped deflectionmovement towards said first side 115 of the female coupling recess 30, until thefirst Iocking element 50 of the male coupling tongue 40 snaps together with thematching second Iocking element 60 of the female coupling recess 30. Suchdeflection movement is illustrated in the schematic example of Fig. 3. A facilitatedinsertion of the male coupling tongue 40 into the interlocked position may thus beprovided, while achieving a robust and stable interlocked state.

The first Iocking element 50 may comprise a continuously curved bulb-shapedprotrusion 240 extending from the male coupling tongue 40, as illustrated in e.g.Fig. 3. This provides for an improved structural integrity with a reduced risk ofunwanted deformations, while a facilitated manufacturing of the first Iockingelement 50 may be provided.

The second Iocking element 60 may comprise a concave Iocking groove 270conforming at least partly to the bulb-shaped protrusion 240 for interlockingengagement therewith, as illustrated in Fig. 1. The bulb-shaped protrusion 240may thus smoothly engage with the concave Iocking groove 270 while maximizingthe area of contact between the two, allowing for reducing localized points of increased pressure if a load is applied onto the first or second furniture part 10, 20.

The upper guiding surface 110 may extend essentially in parallel with alongitudinal direction 31 of the female coupling recess 30, as schematicallyillustrated in Fig. 2. The upper guiding surface 110 may extend directly from thesecond Iocking element 60 of the female coupling recess 30 in a direction towardsan insertion opening 32 of said female coupling recess 30. Such arrangement ofthe upper guide surface 110 provides for an effective and reliable guiding of the first Iocking element 50 into the correct interlocking position in the adjacent second Iocking element 60 along the longitudinal direction 31.

The lower guiding surface 130 may be curved. Having a curved guiding surface130 provides for a facilitated guiding of the male coupling tongue 40 into the finalinterlocked state in the female coupling recess 30, as the guiding surface 130 mayexert a force in gradually changing directions against the male coupling tongue 40for deflection thereof as described above, as the latter is pushed and advanceddownwards into the final position. As elucidated above, the lower guiding surface130 may form part of the inclined surface 48 and the lateral Iocking surface 170, effectively being combined to form a curved lower guiding surface 130. Althoughthe example in Fig. 3 show a defined edge where guiding surface 130 referencenumeral is indicated, it is conceivable that the inclined surface 48 and the laterallocking surface 170 forms a smoother transition.

Hence, the lower guiding surface 130 may be inclined relative to a longitudinaldirection 31 of the female coupling recess 30. l.e. the lower guiding surface 130may effectively be defined at least partly by the inclined surface 48 at the secondside 116 of the female coupling recess 30 as shown in e.g. Fig. 2.

The male coupling tongue 40 may be integrally formed with the first furniture part10 and the female coupling recess 30 may be integrally formed with the secondfurniture part 20. This provides for a robust joining system 1 which can absorbhigher force loads, as well as a facilitated manufacturing of the joining system 1with a reduced number of separate parts.

The male coupling tongue 40 may comprise side support surfaces 181 which mayextend perpendicular from a base portion 41 of the male coupling tongue 40 onthe second furniture part 20, as schematically illustrated in Fig. 2. The side supportsurfaces 181 are arranged for direct abutment against support surfaces 171 on thefirst furniture part 10. This provides for symmetrical side stability and bendingresistance in a locked and joined state between the first furniture part 10 and thesecond furniture part 20.

A width (A) at a base portion 41 of the male coupling tongue 40 may be wider thana width (B) of the male coupling tongue 40 at the first locking element 50 thereof,as illustrated in Fig. 4. Having a wider base portion 41 provides for a furtherincreased side stability of the joining system 1. The width (B) may be wider than awidth (G) of the female coupling recess 30 at the upper guiding surface 110, asillustrated in Fig. 4. This provides for an efficient and robust interlockingmechanism. The width (H) of the most distal part of the male coupling tongue 40,at the lateral locking surface 170, may be less than the widths A, B, and G. Thisprovides for attaining a facilitated deflection of the distal part of the male couplingtongue 40, as illustrated in Fig. 3, while having a robust base portion 41 and areliable interlocking mechanism.

The first Iocking element 50 may come to rest at an edge 42 of the upper guidingsurface 110, as shown in Fig. 5, before the lower guiding surface 130 force themale coupling tongue 40 to resiliently deflect, upon insertion of the male couplingtongue 40 (Fig. 3). Turning again to Fig. 5, the male coupling tongue 40 extendsfrom a base surface 43 of the second furniture part 20, where the base surface 43extends perpendicular to a longitudinal direction 245 of the male coupling tongue40. A length D extends from the base surface 43 to the aforementioned edge 42,as shown in Fig. 5. The lateral Iocking surface 170 is angled from the longitudinaldirection 31 of the female coupling recess 30 at an upper edge 44. The upperedge 44 thus corresponds to the apex or tip where the lateral Iocking surface 170joins or transitions into the inclined surface 48 of the second side of the femalecoupling recess 30, as illustrated in Fig. 4. A length C extends from the basesurface 43 to said upper edge 44. ln one example the length D is less than thelength C. ln one example, when the first Iocking element 50 comes to rest at the edge 42 ofthe upper guiding surface 110, the length C may be less than the length F of themale coupling tongue 40 along a longitudinal direction 245 thereof, as illustrated inFig. 5. Hence, when the first Iocking element 50 comes to rest at the edge 42 ofthe upper guiding surface 110, a portion of the male coupling tongue 40 havealready been guided into position against the lateral Iocking surface 170. Thisprovides for improved control of the position of the male coupling tongue 40 beforebeing deflected towards the first side 115. This provides for a robust interlockingmechanism between the first and second furniture parts 10, 20. Having a length Vbeing less than the length K as indicated in Fig. 5 also provides for such improvedcontrol of the position of the male coupling tongue 40 before being deflectedtowards the first side 115. The length V extends from the base surface 43 of themale coupling tongue 40 to the upper edge of the guide surface S of the femalecoupling recess. The length K extends from the base surface 43 to edge 46 of themale coupling tongue 40.

The length F of the male coupling tongue 40 along a longitudinal direction 245thereof may be less than a depth P of the female coupling recess 30, as illustratedin the example of Fig. 4. This provides for avoiding unwanted tension between atip portion of the male coupling tongue 40 and the base portion of the femalecoupling recess 30, as well as accommodating variations in manufacturingtolerances.

As mentioned, the first Iocking element 50 may come to rest at an edge 42 of theupper guiding surface 110 before the lower guiding surface 130 force the malecoupling tongue 40 to resiliently deflect, upon insertion of the male couplingtongue 40. The female coupling recess 30 may be recessed from a base surface21 of the first furniture part 10, where the base surface 21 extends perpendicularto a longitudinal direction 31 of the female coupling recess 30. A length E extendsfrom the base surface 21 to said edge 42, as shown in Fig. 5. The male couplingtongue 40 may comprise a base portion 41 having a vertical surface 45 facing thesecond side 116 in the interlocked state. The vertical surface 45 may beessentially parallel with a longitudinal direction 245 of the male coupling tongue40. The vertical surface 45 may transition to an inclined surface 47, with respect tothe longitudinal direction 245, at an edge 46, as further shown in Fig. 5. Asmentioned, the male coupling tongue 40 may further extend from a base surface43 of the second furniture part 20, where the base surface 43 extendsperpendicular to the longitudinal direction 245. A length K extends from the basesurface 43 to the edge 46. The length E may be less than the length K.

The male coupling tongue 40 may comprise a base portion 41 having a verticalsurface 45 facing the second side 116 in the interlocked state. The vertical surface45 may be essentially parallel with a longitudinal direction 245 of the malecoupling tongue 40. The lateral Iocking surface 170, and the first Iocking element50, as well as the vertical surface 45 may be arranged to lock the male couplingtongue 40 in the horizontal direction, perpendicular to the longitudinal direction245, as seen in Fig. 4. The lateral Iocking surface 170 faces an opposite secondsurface 172 of the female coupling recess 30, as shown in Fig. 5. The malecoupling tongue 40 and the second surface 172 may be separated by a distanced3. This provides for accommodating tolerance variations, and preventingunwanted tension forces between male coupling tongue 40 and the femalecoupling recess 30.

The aforementioned vertical surface 45 of the male coupling tongue 40 maytransition to an inclined surface 47, with respect to the longitudinal direction 245.The inclined surface 47 may face an opposite second inclined surface 48 of thefemale coupling recess 30 in the joined state, as shown in the example of Fig. 4.The second inclined surface 48 may transitions into the lateral Iocking surface170. The inclined surface 47 and the second inclined surface 48 may be 11 separated by a distance d1 in thejoined state, as further illustrated in Fig. 4. Thisprovides for avoiding unwanted tension between the male coupling tongue 40 andfemale coupling recess 30 in the joined state when a force vertical force is applied.The force may instead be concentrated to the horizontal base surfaces 21, 43, ofthe first and second furniture parts 10, 20. The base surfaces 21 on either side ofthe female coupling recess 30 may be arranged at the same height relative thefemale coupling recess 30, as illustrated in the example of e.g. Fig. 5. Suchsymmetry provides for a robust joining system 1 with an improved absorption ofloads in multiple directions. ln the latter example, the corresponding base surfaces43 at either side of the male coupling tongue 40 are equally arranged at the sameposition along the longitudinal direction 245. However, it should be understoodthat in case the second furniture part 20 joins the first furniture part 10 at an angledifferent from 90 degrees, such as 70 degrees, 50 degrees, 45 degrees, 30degrees etc, the base surfaces 43 may be correspondingly angled toaccommodate such angular configuration.

The upper guiding surface 110 may face an opposite second surface 49 of themale coupling tongue 40 in the joined state. The guiding surface 110 and thesecond surface 49 may be separated by a distance d2 in the joined state, asshown in Fig. 4.

The surfaces of the second side 116 of the female coupling recess 30 indicatedwith S in Fig. 5 provide a counter force towards the male coupling tongue 40 whenthe latter slides against upper guiding surface 110, until reaching the interlockingengagement.

The male coupling tongue 40 may comprise a removable locking element 240defining an outer contour of the male coupling tongue 40, as schematicallyillustrated in the example of Fig. 7a. The locking element 240 is configured to bearranged within the female coupling recess 30, as shown in Fig. 7b. Thus, theremovable locking element 240 comprises said first locking element 50 configuredfor a snap joint interlocking engagement with the matching second locking element60 in the female coupling recess 30. Since the locking element 240 is removablyattached it allows for facilitating different mounting options of the first and secondfurniture parts 10, 20. For example, the second furniture part 20 in Fig. 7c may bemounted in two different directions by turning the latter around the longitudinaldirection 245 before the removable locking element 240 is attached to the male 12 coupling tongue 40. The male coupling tongue 40, with the removable Iockingelement 240 attached thereto, may then be joined with the female coupling recess30. lt should be understood that while the female coupling recess 30 in Figs. 7a-cshows two opposite Iocking elements 60, 60', the dual mounting options asdescribed above are realized with a female coupling recess 30 having only oneIocking element 60 due to the Iocking element 240 being removable as described.

The male coupling tongue 40 may comprise a core portion 241 positionable insidea cavity 242 of the removable Iocking element 240 in an interlocking position ofrespective mating surfaces 243, 244 so that the removable Iocking element 240defines said outer contour of the male coupling tongue 40. The mating surfaces243, 244, may be at least partly symmetrically aligned with respect to alongitudinal direction 245 of the male coupling tongue 40 so that the removableIocking element 240 is positionable around the core portion in a first position, inwhich the first Iocking element 50 extends in a first radial direction r1, and in asecond direction, in which the first Iocking element 50 extends in a second radialdirection r2, opposite the first radial direction r1 as illustrated in Fig. 7c.Analogously, the removable Iocking element 240 may be maintained in onedirection, e.g. having the first Iocking element 50 facing the first radial direction r1,while the second furniture part 20 is flipped around the longitudinal axis 245,before the core portion 241 is positioned inside the cavity 242, due to thesymmetrically aligned mating surfaces 243, 244.

The Iocking element 240, when in interlocking engagement with the matchingsecond Iocking element 60 in the female coupling recess 30, may be arranged toprevent mutual separation of the furniture parts 10, 20 when subjected to aseparation force applied between the first furniture part 10 and the second joiningpart 20. This thus prevents the male coupling tongue 40 from movement in alongitudinal direction of the male coupling tongue 40 with respect to the femalecoupling recess 30 in a locked and joined state between the first furniture part 10and the second furniture part 20.

The Iocking element 240 may be generally U-shaped, as shown in the examplesof Figs. 7a-c. The Iocking element 240 may comprise a polymer material.

The female coupling recess 30 may extend along a length L of the first furniturepart 10, as shown in the perspective view of Fig. 8a. The Iocking element 240 may 13 be slidable along the length L relative the male coupling tongue 40, when in theinterlocking engagement, to be pushed out from the female coupling recess 30and detached from the first and second furniture parts 10, 20. This allows fordeliberate separation between the first furniture part 10 and the second furniturepart 20 when detached. The female coupling recess 30 may comprise a groove246 at a bottom part thereof, which provides for facilitating engagement with thelocking element 240 with a tool to push the latter out from the female couplingrecess 30.

The first locking element 50 may extend along intermittent lengths L1' of the malecoupling tongue 40 along a length L' of the second furniture part 20, as shown inthe schematic perspective view of Fig. 9. The intermittent lengths L1' may be areseparated by male decoupling sections L2'. The second locking element 60 mayextend along intermittent lengths L1 of the female coupling recess 30 along alength L of the first furniture part 10. The intermittent lengths L1' may be separatedby female decoupling sections L2. The first and second furniture parts 10, 20, maybe slidable relative to each other along said lengths L, L', in said interlockingengagement, to a decoupling state in which the male decoupling sections L2'overlap with the second locking element 60 and the female decoupling sections L2 overlap with the first locking element 50 to allow deliberate separation between the first furniture part 10 and the second furniture part 20. A facilitated separation maythus be provided. The male decoupling sections L2' may thus freely slide past thesecond locking element 60 without engaging the latter with a retention force.Likewise, the female decoupling sections L2 may freely slide past the first lockingelement 50 without engaging the latter. The male and female decoupling sectionsL2', L2, may comprise flat surfaces, free from e.g. protrusions 240 and grooves270.

The first and second furniture parts 10, 20 may be joined along an inclined cornersurface 301 at a cornerjoint 300 thereof, as illustrated in Fig. 6. The cornersurface 301 may be have an inclination of 45 degrees. The first and secondfurniture parts 10, 20 may comprise mutual interlocking surfaces formed as arecess 304 in the second furniture part and a protrusion 303 in the first furniturepart 10. The recess 304 may be arranged between the male coupling tongue 40and a corner edge 302 of the cornerjoint 300. A robust and reliable cornerjoint300 may thus be provided. 14 The joining system according to the invention is equally applicable to a widevariety of materials, such as for example solid wood, Iaminated wood, differenttypes of fibreboard materials like MDF or HDF materials, plastic or compositepolymer materials like PVC, or other polymer materials and metals such asaluminium. The joining system may also be used forjoining hollow profile beamsin plastic, steel or aluminium. lt is to be understood that the present invention is not limited to the embodimentsdescribed above and illustrated in the drawings and a skilled person will recognizethat many changes and modifications may be made within the scope of theappended claims.

Claims (24)

1. Joining system (1)for furniture parts (10, 20), comprising a female coupling recess (30) formed in a first furniture part (10), a male coupling tongue (40) projecting from an adjoining second furniturepart (20), said female coupling recess (30) being adapted to receive the malecoupling tongue (40), said male coupling tongue (40) comprising a first lockingelement (50) configured for a snap joint interlocking engagement with a matchingsecond locking element (60) in said female coupling recess (30), the malecoupling tongue (40) is configured to be more flexible than the female couplingrecess (30), an upper guiding surface (110) arranged on a first side (115) ofthe femalecoupling recess (30) on the first furniture part (10), forming an essentially non-resilient guide for the male coupling tongue (40) upon insertion thereof, limitingmovement of said male coupling tongue (40) in a direction towards said first side(115) ofthe female coupling recess (30), a lower guiding surface (130) arranged on a second side (1 16) of the femalecoupling recess (30) on the first furniture part (10), located opposite to said firstside (115) thereof, said lower guiding surface (130) is configured to force the malecoupling tongue (40) to resiliently deflect whilst in engagement with said upperguiding surface (110) upon further insertion thereof in a deflection movementtowards said first side (115) ofthe female coupling recess (30), until the firstlocking element (50) of the male coupling tongue (40) snaps together with thematching second locking element (60) of the female coupling recess (30), wherein said lower guiding surface (130) at its lowest end (160) transitionsinto a lateral locking surface (170) extending essentially parallelly to a longitudinaldirection of the female coupling recess (30), said lateral locking surface (170) isconfigured to exert a horizontal pressure (P) on the male coupling tongue (40)towards said first side (115) ofthe female coupling recess (30), holding the firstand second locking elements (50, 60) of the male coupling tongue (40) and thefemale coupling recess (30) in engagement with each other in a joined statebetween the first furniture part (10) and the second furniture part (20).

2. The joining system according to claim 1, wherein said lower guidingsurface (130) is configured to force the male coupling tongue (40) to resilientlydeflect whilst in engagement with said upper guiding surface (110) upon further 16 insertion thereof in a curved J-shaped deflection movement towards said first side(115) of the female coupling recess (30), until the first Iocking element (50) of themale coupling tongue (40) snaps together with the matching second Iockingelement (60) of the female coupling recess (30).

3. The joining system according to claim 1 or 2, wherein the first Iockingelement comprises a continuously curved bulb-shaped protrusion (240) extendingfrom the male coupling tongue (40).

4. The joining system according to claim 3, wherein the second Iockingelement (60) comprises a concave Iocking groove (270) conforming at least partlyto the bulb-shaped protrusion for interlocking engagement therewith.

5. The joining system according to claim 1 or 2, wherein the upper guidingsurface (110) extends essentially in parallel with a longitudinal direction (31) of thefemale coupling recess (30), and wherein the upper guiding surface (110) extendsdirectly from the second Iocking element (60) of the female coupling recess (30) ina direction towards an insertion opening (32) of said female coupling recess (30).

6. The joining system according to any one of claims 1 to 5, wherein thelower guiding surface (130) is curved.

7. The joining system according to any one of claims 1 to 6, wherein thelower guiding surface (130) is inclined relative to a longitudinal direction (31) of thefemale coupling recess (30).

8. The joining system according to any one of claims 1 to 7, wherein the malecoupling tongue (40) is integrally formed with the first furniture part (10) and thefemale coupling recess (30) is integrally formed with the second furniture part (20).

9. The joining system according to any one of claims 1 to 8, wherein sidesupport surfaces (181) extend perpendicular from a base portion (41) of the malecoupling tongue (40) on the second furniture part (20) for direct abutment againstsupport surfaces (171) on the first furniture part (10), providing symmetrical sidestability and bending resistance in a locked and joined state between the firstfurniture part (10) and the second furniture part (20). 17

10. The joining system according to any one of claims 1 to 9, wherein a width(A) at a base portion (41) of the male coupling tongue (40) is wider than a width(B) of the male coupling tongue (40) at the first locking element (50) thereof.

11. The joining system according to any one of claims 1 to 10, wherein thefirst locking element (50) comes to rest at an edge (42) of the upper guidingsurface (110) before the lower guiding surface (130) force the male couplingtongue (40) to resiliently deflect, upon insertion of the male coupling tongue (40), the male coupling tongue (40) extends from a base surface (43) of thesecond furniture part (20), the base surface (43) extending perpendicular to alongitudinal direction (245) of the male coupling tongue (40), a length (D) extends from the base surface (43) to said edge (42), wherein the lateral locking surface (170) is angled from the longitudinaldirection (31) of the female coupling recess at an upper edge (44), a length (C) extends from the base surface (43) to said upper edge (44), wherein D is less than C.

12. Thejoining system according to claim 11, wherein, when the first lockingelement (50) comes to rest at the edge (42) of the upper guiding surface (110), thelength C is less than the length F of the male coupling tongue (40) along alongitudinal direction (245) thereof.

13. The joining system according to any one of claims 1 to 12, wherein thelength (F) of the male coupling tongue (40) along a longitudinal direction (245)thereof is less than a depth (P) of the female coupling recess (30).

14. The joining system according to any one of claims 1 to 13, wherein thefirst locking element (50) comes to rest at an edge (42) of the upper guidingsurface (110) before the lower guiding surface (130) force the male couplingtongue (40) to resiliently deflect, upon insertion of the male coupling tongue (40), the female coupling recess (30) is recessed from a base surface (21) of thefirst furniture part (10), the base surface (21) extending perpendicular to alongitudinal direction of the female coupling recess (30), a length (E) extends from the base surface (21) to said edge (42), the male coupling tongue (40) comprises a base portion (41) having avertical surface (45), being essentially parallel with a longitudinal direction (245) ofthe male coupling tongue (40), facing the second side (116), 18 wherein the vertical surface (45) transitions to an inclined surface (47), withrespect to the longitudinal direction (245), at an edge (46), the male coupling tongue (40) extends from a base surface (43) of thesecond furniture part (20), the base surface (43) extending perpendicular to thelongitudinal direction (245), a length (K) extends from the base surface (43) to the edge (46), wherein E is less than K.

15. The joining system according to any one of claims 1 to 14, the malecoupling tongue (40) comprises a base portion (41) having a vertical surface (45),being essentially parallel with a longitudinal direction (245) of the male couplingtongue (40), facing the second side (116), wherein the lateral locking surface (170), first locking element (50) and thevertical surface (45) locks the male coupling tongue (40) in the horizontal direction,perpendicular to the longitudinal direction (245).

16. The joining system according to any one of claims 1 to 15, the malecoupling tongue (40) comprises a base portion (41) having a vertical surface (45),being essentially parallel with a longitudinal direction (245) of the male couplingtongue (40), facing the second side (116), wherein the vertical surface (45) transitions to an inclined surface (47), withrespect to the longitudinal direction (245), wherein the inclined surface (47) faces an opposite second inclined surface(48) of the female coupling recess (30) in the joined state, the second inclinedsurface (48) transitions into the lateral locking surface (170), wherein, in the joined state, the inclined surface (47) and the second inclinedsurface (48) are separated by a distance (d1).

17. The joining system according to any one of claims 1 to 16, wherein theupper guiding surface (1 10) faces an opposite second surface (49) of the malecoupling tongue (40) in the joined state, wherein, in the joined state, the guidingsurface (110) and the second surface (49) are separated by a distance (d2).

18. The joining system according to any one of claims 1 to 17, wherein themale coupling tongue (40) comprises a removable locking element (240) definingan outer contour of the male coupling tongue (40), wherein the locking element(240) is configured to be arranged within the female coupling recess (30), whereby 19 the removable Iocking element (240) comprises said first Iocking element (50)configured for a snap joint interlocking engagement with said matching secondIocking element (60) in the female coupling recess (30).

19. The joining system according to claim 18, wherein the male couplingtongue (40) comprises a core portion (241) positionable inside a cavity (242) of theremovable Iocking element (240) in an interlocking position of respective matingsurfaces (243, 244) so that the removable Iocking element (240) defines said outercontour of the male coupling tongue (40), wherein the mating surfaces are at least partly symmetrically aligned withrespect to a longitudinal direction (245) of the male coupling tongue (40) so thatthe removable Iocking element (240) is positionable around the core portion in afirst position, in which the first Iocking element (50) extends in a first radialdirection (r1), and in a second direction, in which the first Iocking element (50)extends in a second radial direction (r2), opposite the first radial direction (r1).

20. The joining system according to claims 18 or 19, wherein said Iockingelement (240), when in interlocking engagement with said matching secondIocking element (60) in the female coupling recess (30), is arranged to preventmutual separation of the furniture parts (10, 20) when subjected to a separationforce applied between the first furniture part (10) and the second joining part (20),thus preventing the male coupling tongue (10) from movement in a longitudinaldirection of the male coupling tongue (10) with respect to the female couplingrecess (30) in a locked and joined state between the first furniture part (10) andthe second furniture part (20).

21. _ The joining system according to any one of claims 18 to 20, wherein theIocking element (240) is generally U-shaped.

22. The joining system according to any one of claims 1 to 21, wherein thefemale coupling recess (30) extends along a length (L) of the first furniture part(10), the Iocking element (240) is slidable along said length (L) relative the malecoupling tongue (40), when in said interlocking engagement, to be pushed outfrom said female coupling recess (30) and detached from the first and secondfurniture parts (10, 20), allowing deliberate separation between the first furniturepart (10) and the second furniture part (20) when detached.

23. The joining system according to any one of claims 1 to 22, wherein thefirst locking element (50) extends along intermittent lengths (L1') of the malecoupling tongue (40) along a length (L') of the second furniture part (20), whereinthe intermittent lengths (L1') are separated by male decoupling sections (L2'), wherein the second locking element (60) extends along intermittent lengths(L1) of the female coupling recess (30) along a length (L) of the first furniture part(0), wherein the intermittent lengths (L1') are separated by female decouplingsections (L2), whereby, the first and second furniture parts are slidable relative toeachother along said lengths (L, L'), in said interlocking engagement, to adecoupling state in which the male decoupling sections (L2') overlap with thesecond locking element (60) and the female decoupling sections (L2) overlap withthe first locking element (50) allowing deliberate separation between the firstfurniture part (10) and the second furniture part (20).

24. The joining system according to any one of claims 1 to 23, wherein thefirst and second furniture parts (10, 20) arejoined along an inclined corner surface(301) at a cornerjoint (300) thereof, wherein the first and second furniture parts(10, 20) comprises mutual interlocking surfaces formed as a recess (304) in thesecond furniture part and a protrusion (303) in the first furniture part (10), therecess (304) being arranged between the male coupling tongue (40) and a corneredge (302) of the cornerjoint (300).