GB2357327A

GB2357327A - A furniture panel connection device

Info

Publication number: GB2357327A
Application number: GB9929611A
Authority: GB
Inventors: Miguel Angel Rioja Calvo
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-12-16
Filing date: 1999-12-16
Publication date: 2001-06-20
Anticipated expiration: 2019-12-16
Also published as: GB9929611D0; GB2357327B

Abstract

A device for joining furniture panels comprises a spindle (6) and an expanding plug (11) with an external extension (13). The spindle (6) has a head (9) and a rod which, at its widest part, has a smaller diameter than the head (9). The spindle rod (6) has an expander foot (7), and the expanding plug (11) is formed of equal feet (14) separated by a groove (18). The external front extension (13) has an annular head (15) which has internal diameters (17a, 17b) which are less than the spindle head (9) but more than the diameter of the spindle rod allowing insertion of the spindle in the expanding plug through a mouth (17) of the external front extension (13).

Description

2357327 CONNECTION DEVICE FOR FURNITURE PANELS This invention relates to a

device to provide a perpendicular joint between a first and second panels and the fittings which hold them in a rotating connection, which is embedded on one face of the first panel in a housing which is close to one edge of this, with communication made through a radial passage in which a projecting part of a metal spindle is located. This has a foot anchored in a hidden hole in one face of the second panel and, opposite this foot, the spindle has a head which penetrates the housing where it is held in a groove on the eccentric perimeter of a rotating connection. On turning, this applies an axial traction on the spindle whose foot acts as the expanding nucleus of an expanding plastic plug, which has internal wedge shapes, which are linked Wth others in the so-called foot and with a separating collar between the joined panels, this expanding stopper is extended with an external front extension which extends over part of the projecting part of the spindle. The axial traction is produced because the lower part of the head of the spindle is supported by an internal wall of the so-called groove (of the rotating clamp) which has a cam section with a smaller radius than the turning shaft of this rotating connection.

PREVIOUS STATE OF THE TECHNIQUE Nowadays, solutions are known which comprise a metal spindle provided with its corresponding expanding plastic plug and the front extension of this. And in all the known constructions the spindle, itself, is made of a metallic material known as Zamak.

In accordance with one of these types of known solutions, the metal spindle and the plastic part of the expanding plug and its front extension, are made 2 separately. In a later operation the spindle is axially inserted by the head end into the mouth or internal end of the expanding plug until, through a flexible opening, the so-called head of the spindle comes out of the mouth opposite the separable feet of the expanding plug. This flexible opening is combined with any sort of gradation formed on the spindle rod (independently of the expanding wedge-shaped configuration), with the aim of immobilising this plastic pin along its axis.

This type of solution implies that the expanding plug has a minimum diameter, which is sufficient to allow the head to pass right through the flexible opening. This means the expanding plug cannot be fine enough for some applications in furniture.

The second type of solution referred to previously has been developed precisely to be able to provide an expanding plug which is thin enough for the applications mentioned in the previous paragraph. This solution consists in moulding the expanding plastic plug (and its front extension) directly onto the spindle. This presents various problems; on the one hand, great precision is needed to position the spindle in the mould for the overmoulding of the plastic part, since, otherwise the mould could easily be broken; on the other hand, this overmoulding operation is, itself, complex and costly; both in terms of its execution and in terms of the resources required; on the other hand, these wedge-shaped structures configured reciprocally in the expander foot of the spindle and the expanding plug, have to be, in the spindle, in bas- relief with reinforcement cores, needed in the Zamak mould (since if they are created in a larger section, this will cancel out the reduction in diameter following the overmoulding), which will make the spindle too weak for many applications. The known solutions of this type give rise to configurations of four reinforcement cores or two wedges positioned opposite each other, all of which are needed for the use of low-resistance mould material.

3 Given this situation, the new device proposed includes a spindle and an expanding plug with its external projection, with the following specific characteristics: the spindle is constructed of pressed steel and has a rod which, at its widest point has a diameter of considerably less than its head and whose spindle rod is totally smooth except for so-called shaping of the expander foot, and the expanding plug has an open configuration, which is formed of two equal feet separated by a groove and, at any time, only linked with each other at the end of this external front projection, situated beyond the collar and using an annular head whose internal diameters are considerably less than the head of the spindle and whose internal diameters are more than the considerably smaller diameter of the rod of this spindle allowing the insertion of the spindle in the stopper through the mouth opposite the feet.

As can be appreciated, this invention is only of interest with regard to the configuration of the spindle and the expanding plug as a result of the expansion of the latter; a configuration for which, on the other hand, many variants are known, not just for the attachment of the spindles in question, but also for the attachment of other types of fittings also used in furniture.

However, the main point of the invention is the mode of structuring the expanding plug (and its front projection) through two equal feet which join on an annular head, and the use of a pressed steel spindle, whose head cannot be passed inside the expanding plug (and its front projection).

This implies a new type of solution for the constitution of the spindle and expanding plug (with its front projection) unit, which presumes a radical change in design. Now the spindle is inserted through the mouth of the annular head, which terminates the front projection of the expanding plug.

And this new solution has, as its primary and most important advantage, the ability to create expanding plugs which are much thinner, including the 4 diameter of the head of the spindle; and, therefore, thin enough to make it suitable for applications which cannot be achieved with the known solutions of the first type given above.

This new device is possible because of the use of a pressed steel spindle, which allows thinner constructions, with much greater strength than the traditional ones made of Zamak.

Another advantage of the new device is its great simplicity and low cost compared with the overmouiding construction system.

The invention will now be described in greater detail, by way of example, with reference to the drawings, in which:

Figure 1 shows the device installed, in operation, in the joint between the first (1) and second (2) panel; the expanding plug (11) unit and the front extension (13) is represented in transverse-cross-section and the rotating connection (3) is represented diagrammatically. The expanding plug (11) is a version with a small section (thin section).

Figure 2 shows the spindle (6) facing the front extension (13) and ready to be inserted for operation using axial force as indicated by the arrow marked on spindle (6), to achieve the state shown in figure 1. Figure 2 includes enlarged details which show the front (7a) and rear (7b) tapered faces of the expander foot (7), and the front (11) and rear (11 b) tapered walls of the expanding plug (11).

Figure 3 shows the expanding plug (11) and its front extension (13) represented in accordance with the section Ill - Ill shown in figure 2.

Figure 4 shows the section IV - IV shown in figure 2.

Figure 5 shows an expander foot unit (11) and its front extension (13), in the same way as figure 2, but for a thicker version of the expanding stopper (11) with the other elements of the proposed device remaining unchanged.

Figure 6 shows the section M-VI, indicated in figure 5.

The following references given in these figures:

1. First furniture panel 2. Second furniture panel 3. Rotating connection 3a. Eccentric perimeter groove 4. First panel (1) housing 5. First panel (1) radial passage 6. Spindle 7. Expanding foot of the spindle (6) 7a. Front tapered face of the foot (7) 7b. Rear tapered face of the foot (7) 8. Projecting part of the spindle (6) 9. Head of the spindle (6) 10. Hidden hole in the second panel (2) 11. Expanding plug 11a. Front tapered wall of the plug (11) 11b. Rear tapered wall of the plug (11) 12. Collar 13. Front or external extension of the plug (11) 14. Plug feet (11) 15. Annular head of the front extension (13) of the plug (11) 16. Direction of insertion of the spindle (6) in the plug (11) 17. Spindle insertion mouth 17a. Largest internal diameter 17b. Smallest internal diameter 17c. Tapered joining area between diameters (1 7a) and (1 7b) 1 6 18. Separation groove between feet (14).

With reference to the drawings, the figures show a preferred method of execution of the new device proposed, which comprises a new spindle (6) and expanding plug-front extension (11-13) unit which, as shown in figure 1, is intended for the perpendicular joining of first (1) and second (2) panels. In the first panel (1) there is a housing (4) for a rotating connection (3) which has an eccentric perimeter groove (M) in which a head (9) of the spindle (6) is located, whose rod runs along a radial passage (5) and which is anchored in a hidden hole (10) of the second panel (2) using the expanding plug (11) wflich is expanded by the expander foot (7) of the spindle (6) when, on turning the eccentric connection (3), traction is produced by the groove (3a) on the head (9) which terminates the projecting part (8) of the spindle (6).

The other end of this projecting part (8) is surrounded by the front extension (13) which acts as a guide to in the radial passage (5). The collar (12) acts as a double penetrating stop and as a separator between the first (1) and second (2) panels.

In accordance with the essence of the invention, the new device comprises a spindle (6) and an expanding plug (11) with its external extension (13). It has a specific constitution in which, the so-called spindle (6) is constructed of pressed steel and has a rod which, at its widest point has a diameter of considerably less than its head (9) and whose spindle rod (6) is totally smooth except for the shaping of the expander foot (7), and the expanding plug (11) has an open configuration, which is formed of equal feet (14) separated by a groove (18) and, at any time, only linked to each other at the end of this external front extension (13), situated beyond the collar (12), and using an annular head (15) whose internal diameters (17a and 17b) are considerably less than the head (9) of the spindle (6) and whose internal diameters (17a and 171b) are greater than the considerably smaller diameter of this spindle rod (6) allowing the insertion of the spindle (6) in the stopper (11) through the mouth (17) opposite the feet (14).

7 According to this new constitution, the spindle (6) is inserted (16) in operation (figure 2) through the external mouth (17) of the front extension (13), by an operation which does not require any force, nor flexible opening because the expander foot goes in loosely because of the greater internal diameter (17a) and when it comes into contact with the tapered joining area (17c) between the diameters, the front face (7a) of the foot (7) causes the separation of the feet (14) because the groove (18) allows this and the operation culminates with the location of the expanding foot (7) in the middle of the expanding plug (11). This is carried out easily using the full capacity of elastic separation of the constitution of the two feet (14) which are united only at the annular head (15), i.e. beyond the expanding foot (7). In this respect, in the expander foot (7) of the spindle (6), the mouth (17) of the front extension (13) of the expanding plug (11), the front (7a) and rear (7b) tapered faces, which are joined opposite each other by their larger equal bases and which are joined with the corresponding front (11a) and rear (11b) tapered walls of the expanding stopper are configured coaxially. The front face (7a) of the spindle (6) has a larger diameter than the diameter of the tapered joining area (17c) of the front extension (13) between the internal diameters (17a and 17b) of the insertion mouth (17) and the separation groove (18) between the feet (14) reaches at least the position of the tapered zone (1 7c).

This new design allows the expanding plug (11) to be fine as shown in figures 1 and 3. And, in accordance with the above detailed description, without the complexity or high cost of the known procedure for overmoulding; and without a risk that the spindle (6) could break, due to its current construction of pressed steel.

An additional advantage of the new device is that the better relation between the resistance and the thickness of the spindle (6) allows the same spindle (6) size to be used both for thin expanding plugs (11) (as in figures 1 and 3) and also for thick expanding plugs (11) (figures 5 and 6), even Men the use of the latter requires a greater force to be supported.

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Claims

1 A connection device for furniture panels, in particular a device to give a perpendicular joint between a first panel (1) and a second panel (2) and for application with known fittings, which hold them together by a rotating connector (3) which is embedded on one face of the first panel (1) in a housing (4) which is close to one edge of the panel, with communication with the edge through a radial passage (5) in which there is a projecting part (8) of a metal spindle (6), which has a foot (7) anchored in a hidden hole (10) in one face of the second panel (2) and, on the opposite end to this foot (7), the spindle (6) has a head (9) which penetrates this housing (4) and is held along an eccentric perimeter groove (3a) of a so-called rotating connection (3) which, on turning, applies an axial traction to a so-called spindle (6) whose foot (7) acts as an expanding nucleus of an expanding plastic plug (11) which has internal wedge-shapes which are linked with others in the foot (7) and a collar (12) situated to separate the panels (1,2) the expanding plug (11) is extended with a front extemal extension (13) which extends around part of the projecting part (8) of the spindle (6), wherein the device comprises a spindle (6) and an expanding plug (11) with its external extension (13), and has the following specific characteristics; the spindle (6) is constructed of pressed steel and has a rod which, at its widest point, has a diameter of considerably less than its head (9) and whose spindle rod (6) is totally smooth except for the shaping of the expander foot (7), and the expanding plug (11) has an open configuration, which is formed of two equal feet (14) separated by a groove (18) and, at any time, only linked with each other on the end of the external front extension (13), situated beyond the collar (12), and using an annular head (15) whose internal diameters (1 7a) and (1 7b) are considerably less than the head (9) of the spindle (6) and whose internal diameters (17a) and (17b) are more than the considerably smaller diameter of this spindle rod (6) allowing the insertion of the spindle (6) in the plug (11) through the mouth (17) opposite the feet (14).

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2. A device, in accordance with the claim 1 wherein the expander foot (7) of the spindle (6), the mouth of the front extension (13) of the expanding plug (11), the front (7a) and rear (7b) tapered faces, which are joined opposite each other by their larger equal bases and which are joined with the corresponding front (11 a) and rear (11 b) tapered walls of this expanding plug (11) are configured coaxially.

3. A device, in accordance with the previous claims 1 or 2 wfierein the front face (7a) of the front extension (13) of the spindle (6) has a larger diameter than the tapered joining area (17c) between the internal diameters (17a and 17b) of the insertion mouth (17) and the separation groove (18) between the feet (14) extends at least as far as the tapered joining area (1 7c).

4. A device, in accordance with any preceding claim, wherein the external diameter of the expanding plug (11) is considerably smaller than that of the head (9) of the spindle (6).

5. A device, in accordance with any preceding claim, wherein the external diameter of the expanding plug (11) is greater than or equal to that of the head (9) of the spindle (6).

6. A connection device for furniture panels substantially as described herein with reference to the drawings.