IL100125A - Corner fasteners for bar frames - Google Patents

Description

CORNER FASTENERS FOR BAR FRAMES CORNER FASTENERS FOR BAR FRAMES The present invention relates to profiled bar constructions, mainly frames, and specifically concerns the assembly of the frame corners. Still more specifically, the invention provides for corner or junction fastener blocks which are used as inserts for effecting the connection of two (or more) perpendicular hollow extruded bars to each other to form a corner (or a junction) in a square or rectangular frame.

In order to better appreciate the contribution of the invention to the relevant art, reference shall be had first to Figs. 1 and 2 where the conventional arrangement is depicted. Hence, there is shown a corner fastener insert marked A having a first arm or wing Al and a second wing A2 extending at right angles one with respect to the other. The insert A is usually made of plastic material and is of an H-shaped cross section as clearly seen in Fig. 2. The dimensions of the wings Al and A2 are such that they snugly fit into the hollow of their respective hollow bars Bl and B2. However, this snug fitting does not produce enough friction force to maintain a mechanically durable frame, therefore the addition of blind rivets denoted C are always required.

It is therefore the major object of the invention to provide corner fasteners corresponding in function and structure to the conventional fasteners, however, not requiring additional strengthening measures.

It is a further object of the invention to provide corner fasteners which, upon manual assembling thereof, will produce such friction restraining forces that will make the additional use of rivets redundant.

Thus provided according to the invention is a corner fastener for hollow profiled bar frames, the fastener being generally formed as an angled block having two (or more) wings insertable into respective ends of the bars forming corners or junctions of the frame characterized in that each wing frictionally engages its respective bar at at-least a first and a second, distanced, contact line against one wall forming the outer corner of the frame, and a third contact line against the opposite, inner wall of the frame, lying in a plane extending between the planes defined by the said first and second contact lines .

The said first and third contact lines are preferably located near the outer and inner apexes of the angled block, respectively. Each wing is preferably tapered towards its free end.

If required, a fourth contact line may be added, preferably opposite the said second contact line.

These and further constructional details of the invention will become more clearly understood in the light of the following description of two preferred embodiments of the invention, given by way of example only with reference to Figs. 3-10 of the attached drawings, wherein; - Fig. 1 is a cross sectional view showing the inside of a frame corner using a conventional fastener block or insert; Fig. 2 is a section taken along line II-II~of Fig. 1; Fig. 3 is a sectional view similar to that of Fig. 1, illustrating the features of the novel corner fastener; Fig. 4 is a section taken along line IV-IV of Fig. 3; Fig. 5 is a section taken along line V-V of Fig. 3; Fig. 6 is a section taken along line VI-VI of Fig. 3; Fig. 7 is a section taken along line VII-VII of Fig. 3; Fig. 8 shows a modified embodiment of the corner fastener of Fig. 3; Fig. 9 is a top view of the fastener of Fig. 8; Fig. 10 illustrates the assembly of a frame junction by an insert designed according to the present invention; Fig. 11 is a cross-sectional view of a further embodiment of this invention; Fig. 12 is a section taken along lin -XII-XII of Fig. 11; Fig. 13 is a cross-sectional view of a further embodiment of this invention; Fig. 14 is a section taken along line XIV-XIV of Fig. 13; Fig. 15 is a cross-sectional view of a further embodiment of this invention Fig. 16 is a section taken along line XVI-XVI of Fig. 15; Fig. 17 is a section taken along line XVII-XVII of Fig. 16; Fig. 18 is a cross-sectional view of a further embodiment of this invention; Fig. 19 is a section taken along line XIX-XIX of Fig. 18; Fig. 20 is a section taken along line XX-XX of Fig. 19; Fig. 21 is a three-dimensional front-side view of the fastener insert of Figs. 18 and 20; and Fig. 22 is a three-dimensional rear-side view of the fastener insert of Fig. 18 and 20.

As shown in Fig. 3f the corner fastener insert denoted D comprises a first wing Dl and a second wing D2 which are insertable respectively into hollow bars El and E2. The fastener insert is preferably made of plastic material .

Now, unlike the conventional fastener A of Fig. 1 — where each wing comprises parallel outer and inner surfaces — the outer surface of wing Dl contains a wedge like recess Fl such that a first contact line or, in fact, surface Gl is formed at the extreme upper corner of the wing, and a second contact line or surface HI is formed towards the end of the cantilever-like end of the wing Dl. Hence, the outer wall of the frame, namely the external wall of the bar El, contacts the fastener only along these two friction lines 61 and HI.

At the bottom side a contact line II is formed by relieving or removing the bottom surface of the fastener . block denoted Jl. Furthermore, the extreme free end of the wing Dl tapers inwardly to form a somewhat pointed edge as more clearly seen in Fig. 4 (with respect to the other wing D2 ) .

The inner corner of the fastener D is relieved by a recess K as in the conventional corner blocks (see Fig. 1).

It will be noted that each of the bars El and E2 is supported and held in position by opposite forces, due to the flexibility of the wings Dl and D2, namely forces exerted by the contact lines Gl and HI on the one hand, and oppositely directed force applied at contact line II, the combination of the forces acting against the dismembering of the bars El and E2 one from the other.

Experiments with the fastener as heretofore described show that after assembly by hand of such corners as before described, only vigorous hammering could separate the bars one from the other without, of course using any kind of riveting or other external fastening means.

The embodiment of Figs. 8 and 9 mainly differ in that an additional, fourth contact line is added. Hence, a fastener block L with wings LI and L2 presents first and second contact lines Nl and Ml, a third contact line PI and a fourth contact line Ql; the same applies to the other wing L2, as shown. The recesses Rl and Rl' are.not wedge shaped but in form of troughs. Further, the contact lines Ml and Ql may not present a planar surface but are round as shown. In all other respects the construction and functioning of the fastening blocks is the same as described with relation to the former embodiment.

The embodiment of Fig. 10 exemplifies the adaptation of the corner insert such as shown in Fig. 3 to be used in a frame junction. Using corresponding notation marks, the insert D now comprises three wings 01, D2 and D3, forcibly inserted into bars El, E2 and E3, respectively. The respective friction lines are denoted Gl, HI and II with respect to the bar El; 12, H2 and G2 for the bar E2; and G3, 13 and H3 for the bar E3.

So far, the application of the invention has been exemplified with respect to regular, closed hollow extruded bars. However, as evident from the following embodiments, the basic concept is readily extendable to many other types of profiled bars, which include at least one, open sided, channel-like portion. Hence, as shown in Fig. 11 and 12, bars SI and S2 — which are not hollow — are assembled by fastener D' similar to the fastener D of Fig. 3, presenting the same contact lines Gl', HI' and II' associated with one wing, and G2', H2' and 12' associated with the other wing of the fastener D' .

Therefore, a firm connection is attained, saving the extra work and expense involved in the conventional fastening by a metal bracket (not illustrated), which normally required at least 8 blind rivets.

The application of the invention with respect to. still another type of profiled bars, Tl and T2 is show in Figs. 13 and 14, which needs not to be further elaborated on. Again, saving of eight blind rivets is attained.

The example of Figs. 15-17 is for assembly bars, designated Ul and U2, by two fasteners featuring the principles of the present invention. Thus, one fastener bloc V is inserted into one profiled cavity of the bars, as shown in Figs. 15 and 16, and a second bloc W — into another cavity as clearly seen in Figs. 16 and 17.

Sixteen rivets are conventionally employed for the assembly of these types of bars.

Figs. 19-20 illustrate yet a further embodiment, wherein the bars, Yl and Y2 are hollow but not four-sided. Fastener insert Z presents the usual three pairs of contact lines HI", Gl", I" and H2", G2" and 12", while its shape is so designed that it will fit into the hollow — though irregular — space available within the bars.

The invention thus provides a "rivetless" assembly method of extruded bar frames which is simple, time saving and convenient and therefore advantageous over the conventional arrangements .

Those skilled in the art will readily understand that numerous changes, modifications and variations may be applied to the invention as heretofore exemplified without departing from the scope of the invention as defined in and by the appended claims.

Claims (8)

WHAT IS CLAIMED IS:

1. A fastener insert for the assembly of at least partly hollow profiled bar frames , the fastener being generally formed as an angled block having two or more wings insertable into respective ends of the frame bars, forming corners or junctions of the frame, characterized in that each wing frictionally engages its respective bar at at-least a first and a second, distanced, contact line pressed against one wall forming the outer corner of the frame, and a third contact line pressed against the opposite, inner wall of the frame, lying in a plane extending between the planes defined by the said first and second contact lines.

2. The fastener of claim 1 having two wings, wherein the first contact lines of the two wings are located near the outer apex of the angled block.

3. The fastener of claim 2 wherein the third contact lines are located near the inner apex of the angled block.

4. . The fastener of claim 3 wherein the two wings are cantilevered, the said second contact lines are located near the free end of the wings, respectively.

5. The fastener of claim 4 wherein a shallow step is made in the material of each wing to form at its two sides the said first and second contact lines.

6. The fastener of any of the preceding claims wherein the wings are tapered towards their free ends.

7.. The fastener- of any of the preceding claims wherein a fourth, contact line is formed opposite the said second line.

8. A fastener insert for the assembly of hollow profiled bar frames substantially as hereinbefore described with reference to Figs. 3-22 of the accompanying drawings . For the Applicant DANIEL FREIMAN , Adv. corner.wps