GB2118669A - Improved device for joining structure - Google Patents

Abstract

This invention relates to a type of coupling between two structures (1, 8) in which a pair of wings (4) are passed through a trapezoidal hole (9) having an extension (10) which receives a central strip (3) supporting the wings (4) when the structures (1, 8) are moved into engaged position. In accordance with the present invention, the central strip (3) is formed so as to converge downwardly (5) and extension (10) of the hole has matchingly convergent edges (11), and planes (6) at the top of the strip engage inclined edges (12) at the opening of the extension (10). <IMAGE>

Description

SPECIFICATION Improved device for joining structures The present invention relates to an improved device for joining metal structure of any type and capacity of resistance, disregarding screws, pins, rivets, drivers, and auxiliary tools, achieving an autonomous fixing due to the coupling means incorporated thereto, thereby proportioning substantial and important advantages with respect to the conventional means used in this field for the same purpose.

The device is based on engaging one coupling front with another complementary front, one overlapping the other by sliding until they are fixed and retained.

This is not the first time that an attempt is made to patent a coupling device having these characteristics, since the same applicant has already filed in Spain in February 1 978 Utility Model No. 233,923.

In accordance with the mentioned utility model, one of the coupling fronts is provided with inverted trapezoidal projections laterally torn or split according to the iongitudinal axis thereof, the edge of the larger base of which is a curved recess while the smaller base is joined to the plane only by a central strip.

The other coupling front has holes which are also inverted trapezoidal in shape with a coaxial groove at the smaller edge, determining a support for the central strip of the projection.

The front which incorporates the projection readily penetrates through the hole and once both fronts are juxtaposed, one can merely slide into the other so that the central strip of the projection is housed in the central groove made in the hole, being supported on the bottom thereof, while its larger or upper base is supported on the lower edge of the hole.

Both coupled fronts are overlapped and inseparably retained together, if operation does not take place inversely.

The advantages derived from such highly simple constituting characteristics as those described, are clear. It should also be pointed out that the described device can readily be obtained by mechanical means, determining a very low manufacturing cost and, consequently, it is, commercially, highly competitive.

However, two important defects have been observed in practice which, although they do not make the use of the described device unrecommendable, demonstrate which are the improvements to be introduced to achieve the complete effectiveness.

One of the defects resides in that there is laterally a play or clearance between the groove of the hole and the projecting strip which is coupled therein.

The other defect resides in the support of the projecting front in the bottom of this groove.

In the first case, the structure is not completely fixed and in the second the load limit is low, but even within the load limit, the possibility of a slight lateral movement of the assembly results in shearing stresses which damage it and, consequently, reduces the effective possibilities thereof.

Thus, the main object of this invention resides in the elimination of the clearances and the increase in the loading capacity with the culmination in the complete coupling possibilities.

The improved device for joining metal structures, which will subsequently be described, constitutes the practical realisation of the previously mentioned object and, as will be seen, achieves the desired results without losing any of its advantages with respect to economy and practice which pertain to the original solution.

The first improvement resides in the central strip of the projection and consists in proportioning said central strip of the projection with two lateral converging planes which are complementary of other planes, also converging, provided in the coaxial groove of the hole of the other coupling front.

Due to this innovation, the central strip fits into, it is autocentered, it is blocked laterally, and it is supported on the totality of the sides of the groove, whereby the joining is absolutely rigid.

Another improvement consists in proportioning the upper part of the projection with two inclined planes which are supported on other complementary planes provided at both sides of the groove, thereby obtaining a penetration butt of the central strip and the addition of two support.

planes to the support planes which constitute the lips of the central groove.

Finally, since the bottom of the central groove is conferred with a curved projection, the front of the central strip rests on the bottom, thereby constituting another point of support to these previously mentioned.

The result of all these improvements gives rise to the construction of the mentioned object, i.e. a simple, effective and reliable assembling device which permits a high assembly speed without the need of tools, and once mounted it is rigid, being more firmly supported when the weight which it supports is greater.

To complement the aforegoing and for a better understanding of the mentioned characteristics, there is accompanied to this specification a set of drawings wherein a practical mode of embodiment is represented.

Figure 1 illustrates a perspective view of the two fronts in a position prior to the coupling thereof, one of which represents the projection while the other represents the hole in which said projection' should be fixed.

Figure 2 illustrates a perspective view of the rear portion of the projection.

Figure 3 illustrates a profile and an elevational view of the projection.

Figure 4 represents a perspective view of the coupling of one front and the other, illustrating due to the partial cuts, the overlapping of one part with respect to the other and the different support zones.

Referring to the drawings, there can be seen the device comprised of a metal front 1 which has been provided with a projection 2 having a general inverted trapezoidal shape.

The sides of the projection 2 are torn by stamping and by means of a blanking operation there is obtained the central strip 3, forming two wings 4 which, when overlapped as illustrated in Figure 4, constitute retention clamps.

The inner part 5 of the central strip 3 has two side converging planes which are illustrated in Figures 2, 3 and 4.

The upper part of the projection 2 has two inner inclined planes 6 and the lower part 7 of the projection is slightly concave.

The metal front 8, on the other hand, has the hole 9 which is an inverted trapeze, the smaller base of which is provided with a groove 10 with its converging lips 11 which will constitute support, autocentering and lateral blocking planes of the converging sides 5 provided in the projection 2.

At both sides of the groove 10 there are formed two inclined planes 12 acting as a support for the upper inner inclined planes 6 provided in the projection 2, and the bottom 13 of the groove 10 is convex acting as a support for the lower part 7 of the central strip 3.

The process of coupling is carried out by facing the projection 2 and the hole 9, causing one to penetrate into the other, whereafter a descending movement takes place until the overlapping, as illustrated in Figure 4 of the drawings, is achieved.

When the support has taken place, the inner planes 6 are locked between the lips 11 of the groove, one being closely adjusted to the other without the possibility of lateral movement, thereby producing an autocentering.

The adjustment between the lips 11 and the planes 6 proportions a support for the inclined planes 6 on the inclined planes 12 of the hole 9, while the convex bottom 13 of the groove 10 adapts to the lower part 7, obtaining the complete support of the assembly and, therefore, an absolute locking, which constitutes the object of the invention, together with the spectacular increase in the achieved loading capacity.

Thus, the two fronts are coupled together and are laterally blocked, inasmuch as they cannot be separated due to the clamping effect proportioned by the wings 4 of the projection 2.

The described coupling device is ideal in a multitude of applications for joining any type of structures, i.e. structures having a light loading capacity and, therefore, suitable for domestic use where the user himself carries out the assembly, or for structures having a high loading capacity, whether modular with optional assembling possibilities or singular without assembling options.

Claims (4)

1. Improved device for joining structures of the type comprised of a metal front from which, by blanking and hammering, there emerge inverted trapezoidal projections which, laterally, according to the longitudinal axis thereof, are torn and which at the smaller edge is joined only by a central strip constituting the means for centering and supporting the projection in a hole provided at the other front, which hole has an inverted trapezoidal shape and a coaxial groove at the smaller edge, determining a support for the central strip of the projection which, at the torn edges, overlaps the lower edges of the housing being retained and supported therein, essentially characterised in that each projection has at its central strip two inner converging lateral planes, at its upper part, it forms two inner inclined lateral planes and at the lower part said strip is slightly concave at its outer surface, while the hole has a coaxial groove whose walls or lips are converging, with the same convergence as the lateral planes of the central strip, which fits between the lips of the groove, it is supported therein and it is laterally and axially blocked.

2. Improved device for joining structures according to claim 1, essentially characterised in that the lower edge of the hole, at both sides of the groove, forms two inclined planes acting as a support for the inclined planes of the projection and, furthermore, constitute a penetration butt of the sides of the central strip of the projection between the lips of the groove.

3. Improved device for joining structures according to the preceding claims, essentially characterised in that the bottom of the groove is curvo-projecting and determines a complementary support for the central strip, at its lower part, when same has penetrated into said groove.

4. A device for joining structure substantially as hereinbefore described with reference to the accompanying drawings.