CONNECTING JOINTS FOR COLLAPSIBLE STRUCTURES

Abstract: The invention produces a connection joint (1) for collapsible structures that includes a male component (4) and a female component (5) movably connected into one another. The male (4) and female (5) components have first locking devices (6) that aid the coupling of the male component (4) into female component (5) and second locking devices (7) that can be snap coupled together to lock the components (4, 5) together when the male component (4) is fully fitted into the female component (5).

Description: CONNECTING JOINTS FOR COLLAPSIBLE STRUCTURES The invention concerns a connecting joint for collapsible structures, particularly suited for use in producing collapsible tables. The garden furniture sector and similar often demands tables or other structures that can be easily collapsed and reassembled whenever necessary. This has the purpose of facilitating transport and reducing their dimensions when they are put away or stored. For this reason the ends of the structural elements are shaped so that they provide connecting joints that allow the structure to be constructed, whether the structure be for instance a table, chair or anything else, that are easy to assemble and collapse. Known types of joints generally have male-female fasteners suited to fit into one another to guarantee the mechanical stability of the structure, which are made in the most varied types of forms. Known products have the main disadvantage of providing joints having fasteners that are difficult to locate and are not always easy and quick to set in their fastened position. What's more it can be added that such known joints, primarily in the uncoupling phase, require substantial effort to flex the constituent parts to separate the structural elements. An additional disadvantage is that known productions of joints do not provide components suited to emphasise and guarantee that the parts being joined together have been fastened properly. As a consequence the user is not always aware that the connection has been made properly, above all when the components being joined together are not easy to reach or out of the user's line of vision. This invention intends to overcome these inconveniences. In particular one scope of this invention is to produce a connection joint that has fasteners easily located where they have a quick, clear-cut coupling method. Another scope is that the joint can easily be uncoupled when the user intends to collapse the parts making up the structure. Another scope is that the joint has elements capable of enabling the user to perceive that it has been fastened properly. An additional scope of the invention is to produce a joint that is practically impossible to uncouple by accident, for instance because the structure is handled incorrectly and clumsily after it has been assembled. Last but not least, a scope is that the joint invention can be integrated in the structural elements, whatever their form, so that they do not relinquish the pleasing appearance of the overall structure. Said scopes and any others are achieved by a connection joint for collapsible structures that, in accordance with the main claim, includes a male component and a female component movably connected into one another, characterised in that said components have first locking devices suited to aid the coupling of the male component into the female component and second locking devices that can be snap coupled together suited to lock said components together when the male component is fully fitted into the female component, and having been fastened together, both of said locking devices are suited to prevent the components from sliding apart. Additional characteristics and details of the invention shall be better illustrated during the description of a preferred form of execution that is given as a guideline but not a limitation and is illustrated with reference to the attached diagrams where: - fig. 1 illustrates an isometric blow-up of the components that make up the joint invention; - fig. 2 illustrates one of the components in fig. 1 ; - figures 3 to 5 illustrate the phase where the components are fastened together to form the joint in fig. 1 ; - fig. 6 illustrates the phase where the components forming the joint in fig.1 are unfastened; - fig. 7 illustrates an isometric view of a collapsible table using the joint in fig. 1 ; - fig. 8 illustrates a detail of fig. 1. The connection joint referred to in this invention is illustrated in fig. 1 where it is generally indicated by 1 and is used to join together the ends of two structural elements 2 and 3 preferably but not necessarily having a tubular form belonging to a collapsible structure. The joint 1 includes a male component 4 belonging to the end of the structural element 2 and a female component 5 belonging to the end of the structural element 3, movably connected one inside the other to form a continuous structure. In a variant of its execution, not described or shown in the diagrams for the sake of brevity, the male-female components, instead of being made in a solid block with the structural elements, may be applied to these by means of a special connecting system. Said male 4 and female 5 components have first locking devices generally indicated by 6 suited to aid the coupling and second locking devices generally indicated by 7 that can be snap coupled together suited to lock the structural elements together and to guarantee mechanical continuity when the male component 4 is fully fitted into the female component 5. When fastened, both the locking devices 6 and 7 cooperate to prevent the structural elements 2 and 3 from sliding apart. With regards to the first locking devices 6, they consist of a ridge 8 belonging to the female component 5 and having a convex curvilinear form 8a, that fits into a seat 9 having a concave curvilinear form 9a as seen in fig. 2 belonging to the male component 4. In the form of execution described and illustrated in the attached figures, the convex forms 8a and concave forms 9a have a cross-section basically shaped like the arc of a circle. With regards to the second locking devices 7, they consist of a flexing button 10 on the male component 4, suited to fit into a hole 11 made in the female component 5. The button 10 has a basically cylindrical form and cooperates with a means of flexing 12 suited to make it sit in a hole 13 of larger diameter made in the male component 4, that is preferably but not necessarily made of at least one rib 14 that connects the button 10 to the body of the male component 4. In particular the rib 14 sits inside the perimeter 13a of the hole 13 to guarantee the necessary flexing of the button 10 when it is pressed. It is set at the front of the button in the area where the latter is thinnest. In fact as seen, the top 10a of the button 10 is angled and tapers towards the end of the male component 4 to favour its entry in its respective hole 11 when the male component 4 is fitted into the female component 5. What's more the top 10a also has a bevel 10b suited to aid the pressing of the button 10. The male component 4 also has a flat surface 15, as seen in fig. 2, that continues from the concave seat 9 and that meets with a counterpart second flat surface 16 found inside the female component 3. The connection between the structural elements 2 and 3, as shown in figures 3 to 5, works by bringing the female component 5 up against the male component 4 that is held at an angle 17 so that its concave contour of the seat 9 fits into its respective convex ridge 8 belonging to the female component 5 . Then by making a clockwise turn 18 with the structural element 2 that is aided by sliding the concave curvilinear form 9a of the seat 9 on the convex, curvilinear form 8a of the ridge 8, the button 10, as shown by the detail in fig. 4, flexes back into the hole 13 being pushed against the wall 22 to then fit into the hole 11 , being flexed back by the rib 14 when the coupling is made. When the button 10 enters the hole 11 , the snapping noise heard by the user indicates that the fastening has been completed and ensures that the structural elements have been firmly joined together. When fastened together, the button 10 is blocked against the perimeter of the hole 11 that contains it and the ridge 8 blocked against its respective seat 9. So both locking devices contribute to preventing the components from sliding apart thereby guaranteeing the mechanical continuity of the structure. Simultaneously the alignment between surfaces 15 and 16 also prevents the male 4 and female 5 components from twisting around each other. An abutment 19 along the outer rim of the male component 4 at the point where the structural element 2, when coupled together, butts up against the outside facing edge 20 of the female component 5 and contributes to guaranteeing stability of the joint against the components bending against each other. With regards to unfastening, illustrated in fig. 6, the mechanism is very quick and simple, achieved by a pressure 23 on the button 10 so that it is made to flex into the hole 13 and at the same time making an anticlockwise turn 21 on the structural element 2, combined with sliding the two pieces apart tending to separate one from the other. In a different form of execution the convex ridge 8 may belong to the male component instead of the female component and its respective seat 9 may belong to the female component instead of the male component. The joint 1 described is especially suited for application on a collapsible structure such as for instance collapsible chairs or tables particularly of the type used for the garden as illustrated in fig. 4. In this kind of application the joint 1 is used to join the structural elements making up the legs G of table T that support the tabletop P. Even though the finding has been described with reference to the attached figures, any changes that may be made to its construction shall fall under the claims and therefore be protected by the patent.

Claims: CLAIMS 1 ) Connection joint (1 ) for collapsible structures including a male component (4) and a female component (5) movably connected into one another characterised in that said components (4, 5) have first locking devices (6) suited to aid the coupling of the male component (4) into the female component (5) and second locking devices (7) that can be snap coupled together to lock said components (4, 5) together when the male component (4) is fully fitted into the female component (5), both of said locking devices (6, 7) having been fastened together are suited to prevent the components (4, 5) from sliding apart. 2) Joint (1 ) according to claim 1 ) characterised in that said first locking devices (6) consist of a ridge (8) having a convex form on the female component (5) or on the male component (4) that can be fitted into a seat (9) having a concave form belonging to the male component (4) or the female component (5). 3) Joint (1 ) according to claim 2) characterised in that said curvilinear ridge belonging to said female component (5) and said seat (9) having a concave form belonging to said male component (4), said forms (8, 9) being curvilinear. 4) Joint (1 ) according to claim 1 ) characterised in that said second locking devices (7) consist of a flexing button (10) on the male component (4) suited to fit into a hole (11 ) made in the female component (5). 5) Joint (1 ) according to claim 4) characterised in that said flexing button (10) has a basically cylindrical form and cooperates with a means of flexing (12) suited to make it sit in a hole (13) of a larger diameter made in the male component (4). 6) Joint (1 ) according to claim 5) characterised in that said means of flexing (12) is made of at least one rib (14) that connects said button (10) to the perimeter of said hole ( 3). 7) Joint (1 ) according to any one of claims 1 ) to 3) characterised in that said male component (4) has at least one first flat surface (15) that meets with a counterpart second flat surface (16) found inside the said female component (5). 8) Joint (1 ) according to claim 7) characterised in that said button (10) and said first flat surface (15) are respectively blocked against said hole (1 1 ) and against said second flat surface (16) to prevent the male (4) and female (5) components from twisting around each other. 9) Joint (1 ) according to claim 1) characterised in that said male component (4) has at least one abutment (19) butting up against an outside facing edge (20) of said female component (5).

Inventors: NARDI GIAMPIETRO, NARDI, GIAMPIETRO
Applicants: NARDI GIAMPIETRO, NARDI S P A, NARDI S.P.A., NARDI, GIAMPIETRO
Application year: 1999
Main classification: F16B12
IPC codes: F16B7, F16B12