APPARATUS FOR LINKING ELEMENTS TOGETHER AND METHOD OF FITTING THE APPARATUS IN AN ELEMENT

Abstract: An apparatus for linking elements together, said apparatus comprising a clamping box (1) to be embedded in the edge of an element and being provided with means for the engagement with a clamping box (1) to be embedded in the edge of another element. An objective is to overcome the problems involved in fitting said clamping boxes in element manufacturing. For this purpose, the trailing edge of said clamping box (1) is fitted with pivotable wings (2) which extend obliquely forward beyond the lateral surfaces of said clamping box in a manner that, as the clamping box is withdrawn outwards, said wings (2) pivot away from the box and thereby build a barrier for preventing further withdrawal of the clamping box after a certain distance is covered. Such a clamping box can be fitted in an element by employing a method in which the edge of an element is machined to form a recess for receiving said clamping box (1), an adhesive is applied to the outer surface of said clamping box, the clamping box is inserted into the recess a small distance inside the edge surface of an element, and the clamping box is withdrawn a small distance out of the recess until it reaches a desired position relative to the edge of an element.

Description: Apparatus for linking . elements together and method of fitting the apparatus in an element. The present invention relates to an apparatus for linking elements together, said apparatus comprising a clamping box which is insertable into the edge of an element and provided with means for the engagement with a clamping box inserted in the edge of another element. The invention also relates to a method of fitting such apparatus in an element. The Applicant's Finnish patent 40488 discloses an apparatus of the above type for fastening two building elements by their edges to each other. This prior art apparatus, likewise the other known element fasteners, is already moulded within the edge of an element as the element is manufactured. This requires extreme accuracy in the manufacturing step in order that the clamping boxes can be fitted properly and with required accuracy. One solution for fitting the clamping boxes in proper positions has been disclosed in US Patent publication 3 671 006. An object of the invention is to provide an element fastener of the above type and a method of fitting it in an element so as to eliminate the difficulties involved in the manufacture of. such element. For this objective, an element fastener of the invention is characterized in thatthe trailing edgeof a clamping box is fitted with pivotable wings extending obliquely forward beyond the lateral surfaces of a clamping box in a manner that, when with¬ drawing said clamping box, the wings pivot away from the box and thereby build a barrier that ' after a certain distance prevents further withdrawal of the clamping box. Characteristic of the method is that the edge of an element is machined to form a recess for receiving the clamping box, that an adhesive is applied to the outer surface of said clamping box, that the clamping box is inserted into said recess a small distance inside the edge surface of the element, and that the clamping box is withdrawn a small distance out of the recess until it reaches a desired position relative to the edge of said element. This position is generally reached when the leading edge of said clamping box lies essentially in the same plane as the edge of .said element. It can be appreciated that, when using element fasteners of the invention, the elements can be manufactured and cast with¬ out clamping boxes and accurate fitting required thereby. This facilitates and accelerates considerably the actual manufacture of elements. As the clamping boxes are fitted afterwards by employing the method of the invention, the method can be carried out by means of an automatic machine for effecting the fitting quickly and accurately in desired positions. The invention will now be illustrated with reference made to the accompanying drawings, wherein fig. 1 is a side view of the clamping box of an element fasten¬ er of the invention and fig. 2 is a plan view of the same. A clamping box 1 consists of two superimposed sheets provided with a box portion by means of punching. The superimposed trailing edge 1a of said box sheets is provided with pivot holes 3 which are engaged by loops 2a, 2b formed as hinges for wings 2, 2'. Wings 2 and 2' are positioned on either side of box 1 so as to extend obliquely forward beyond the lateral surfaces of said clamping box. The hinge loops 2a and 2b permit the pivoting thereof to the position illustrated by dash-dot lines in fig. 2. The clamping box is fitted in the element by first machining the element edge to form a recess for receiving the clamping box. This is followed by the application of an adhesive to the outer surface of said clamp¬ ing box and the latter is inserted into said recess in the element a small distance- inside the edge surface of the element. Thereafter, the clamping box is withdrawn a small distance in outward direction from the recess until the lead¬ ing edge surface of said box lies in substantially the same plane as the element edge. This distance of withdrawal is selected so that wings 2 and 2' pivot to their extreme positions as illustrated by dash-dot lines for preventing further withdrawal of the clamping box. The arched configur¬ ation of wings 2 and 2' serves the purpose that, as they pivot, said wings sink better in the element material without tearing it, in other words, there are as few cavities as possible formed between the wings and the element material. If desired, it is possible to use such adhesive that fills possible cavities as it expands. In order to always ensure the turning of wings 2, 2' into the spread position, fitted between said wings 2 and 2' is a spring 4 whose spring force is so small that it does not interfere with insertion of the clamping box into the edge recess of an element.

Claims: Claims 1. An apparatus for linking elements together, said apparatus comprising a clamping box (1) to be embedded in the edge of an element and being provided with means for the engagement with a clamping box (1) to be embedded in the edge of another element, c h a r a c t e r i z e d in that the trailing edge of said clamping box (1) is fitted with pivot- able wings (2) which extend obliquely forward beyond the lateral surfaces of a clamping box in a manner that, as said clamping box is withdrawn outwards, said wings (2) pivot away from the box and thereby build a barrier that after a certain distance prevents -further withdrawal of tHe v "clamping box. 2. An apparatus as set forth in claim 1, c h a r a c t e r ¬ i z e d by a spring (4) which urges the wings (2) towards a spread position. 3. A method of fitting the apparatus of claim 1 in an element, c h a r a c t e r i z e d in that the edge of an element is machined to form a recess for receiving the claimping box (1), that an adhesive is applied to the outer surface of said clamping box, that the clamping box is inserted into the recess a small distance inside the edge surface of the element, and that the clamping box is withdrawn a small distance out of the recess until it reaches a desired position relative to the edge of said element.

Inventors: SUOMINEN VEIKKO ARMAS, SUOMINEN, VEIKKO, ARMAS
Applicants: SUOMINEN VEIKKO ARMAS, SUOMINEN, VEIKKO, ARMAS
Application year: 1983
Main classification: E04B1
IPC codes: E04B1