GB2083116A

GB2083116A - Composite bar

Info

Publication number: GB2083116A
Application number: GB8118101A
Authority: GB
Original assignee: Josef Gartner and Co
Current assignee: Josef Gartner and Co
Priority date: 1980-09-03
Filing date: 1981-06-12
Publication date: 1982-03-17
Also published as: DE3033206A1; NL8103556A; GB2083116B; DE3033206C2

Abstract

A composite bar comprises two section parts (10, 12) joined in the longitudinal direction thereof by thermally insulating section rails (14, 16). These rails (14, 16) have anchored retaining webs (18) which extend longitudinally in slots (20) in the section parts (14, 16). The retaining webs (18) are provided with a series of peaks and recesses, at right angles to the longitudinal direction, and the slots (20) have an inner surface which likewise is provided with a series of peaks and recesses. Between the retaining webs (18) and limiting wall parts of the slots (20) a space (22) is formed into which said peaks extend, and this space is filled with a thermally insulating and mechanically strong filler which provides a positive connection between the section parts (10, 12) and the rails (14, 16). <IMAGE>

Description

SPECIFICATION Composite section This invention relates to a composite section, of the type comprising two section parts which are joined in the longitudinal direction of the section parts by at least one thermally insulating section rail with anchored retaining webs running longitudinally in slots in the section parts.

Composite sections of this type are used for window construction, building shell construction and similar applications. In the joint between the two section parts, high mechanical demands are made by the thermally insulating section rails, especially with regard to the critical longitudinal shear stress, shear strength and resistance to transverse forces. In order to satisfy these exacting requirements, the retaining webs must be securely anchored in the slots. For example, they can be glued into the slots.

Glued joints can, however, age and they then no longer afford the guarantee of an adequately secure anchorage.

It is also possible to construct a part of the wall limiting the slots into which the retaining webs are to be anchored as a deformable shank, and after the insertion of a retaining web into a slot to press this shank against the retaining web. This can, for example, be achieved by rolling. With this the retaining web is firmly fixed in the slot and is partially deformed. In order to allowforthe residual elasticity of the deformed part, it is necessary to press somewhat further against the shank, beyond the position which corresponds with the intended terminal position. With this, charges in stress take place and weaknesses arise not only in the section part, but also in the plastics section, so that the theoretically expected strength cannot, in practice, be closely achieved.The joint obtained in this manner can further be significantly impaired through subse quenttreatment of the composite section, for example anodic treatment, stoving, varnishing, enamelling and the like.

The object of the invention is to obtain a composite section of said type, the strength of which is achieved by positive jointing between the section parts and the section rail, whereby there is no need to fear impairment of the strength achieved as a result of changes in stress and weaknesses of said type. Further, it is made possible for the surface treatment of the section parts to be carried out before their combination into a composite section, so that the strength achieved by the joint is not subsequently lost again as a result of the surface treatment.

This object is achieved by the invention in a composite section of the type referred to at the outset, wherein the retaining webs of the section rail are provided with projections and recesses respectively, extending at right angles to the longitudinal direction, the slots have at least one inner surface which likewise is provided with peaks and recesses respectively extending at right angles to the longitudinal direction, and wherein between the retaining webs and the walls limiting the slots a space is formed into which the peaks extend and which is filled with a filler of mechanically high capacity, which produces a positive joint between the retaining webs and the slots. If necessary, a thermally insulating filler can be used.

The peaks and recesses, respectively, are preferably formed by knurling or grooving.

As filler an age-hardenable casting resin is suitable, especially a two-component casting resin. In a special manner of execution the use of an age hardened, with volume increase, filler is provided for.

In order to bring the section rail into a definite position opposite the section part to which it is to be jointed, complementary anchoring elements can be provided on the section rail and on the section part for joining these with locking seats. The insertion depth of the section rail and retaining web, respectively, in the slots is limited by a lug running longitudinally and which is arranged on the limiting wall of the slot. According to the dimensions and the construction of the retaining webs and the slots, the section rails can be inserted into the slots longitudinally or in the transverse direction laterally. The latterform of execution makes easier handling possible.In order to facilitate the lateral insertion of the profile rail in the transverse direction, a limiting wall of the slot can additionally be formed as a deformable shank which, following insertion of the retaining web into the groove, is pressed against the latter but, however, only so far that it comes against its support without being pressed against it.

The section rail is for preference constructed as a flat section on the edges of which the retaining webs are formed. The section rail may be C- or I-shaped in cross section.

A special form of execution of the invention distinguishes itself in that the retaining webs have two deformable separate expanding shanks separated by a slit and between which a pick-up groove is provided for picking up a filler, age hardenable with volume increase. With age hardening of the filler, the expanding shanks are pressed apart and respectively engage with lugs which extend longitudinally, in each case, along an undercut limiting wall of the slot.

Further advantages and features of the invention will be clear from the following description of several exemplary embodiments of the invention with reference to the accompanying drawings. The drawings show: Figure 1 - an exploded perspective view of two hollow section parts, which are to be joined together by two section rails:: Figure 2 - a fragmentary section through an undercut slot provided on the parts with a retaining web inserted therein; Figure 3 - a sectional view along the line lil - Ill in Figure 2; Figure 4- a sectional view corresponding to Figure 2, but after filling with a filler a space between the slot and the retaining web; Figure 5 - a sectional view along the line V - V in Figure 4; Figure 6 - a sectional view of another embodiment before the insertion of the retaining web in the slot; Figure 7 - a sectional view of the same embodi ment as shown in Figure 6, but after the insertion of the retaining web in the slot and after filling the space with a filler; Figure 8 - a sectional view of a further embodi ment;; Figure 9 - a sectional view of a still further embod iment in which a wall part of the slot, constructed as a deformable shank, is shown in the expanded position; Figure 10 - a view analogous to Figure 9 where, however, the deformable shank is pressed against the inserted retaining web and the remaining space is filled with filler; Figures 11 and 12 view analogous to Figures 9 and 10, but illustrating another embodiment; Figure 13 - a sectional view of an embodiment in which the section rail has a retaining web formed from two expanding shanks, whereby the expanded shanks are separated from each other by a slit and before the age hardening of the expanding filler; and Figure 14- a view corresponding to Figure 13 but in the expanded position of the expanding shanks after age hardening of the expanding filler.

In the embodiment shown in Figures 1 to 5, two section parts 10, 12 are to be joined together by two section rails 14,16. The section parts 10,12 are aluminium sections, for example, whilst the section rails 14,16 are of thermally insulating, mechanically high capacity plastics material. The section rails 14, 16 are flat sections on the longitudinal edges of which retaining webs 18 are formed. The section rails 14, 16 are common Gshape in cross section, whereby the retaining webs 18 form the outer limbs of the "C". Each section part 10,12 is provided, on the side facing the section rails 14,16, with an undercut longitudinal slot 20 for receiving a retaining web 18.Details of the construction of the slots 20 on the one hand, and of the retaining webs 18 on the other hand, emerge from Figures 2 to 5 to which reference will now be made.

The slot 20 is groove shaped in cross section and has a straight inner side wall, a base wall at right angles to this and an outer side wall which extends at right angles to the base wall and in its upper third extends inwardly in order to form an undercut. The retaining web 18 of a section rail 14 is so fitted into the slot 20 that, with one wall, it comes to rest against the inner side wall of the slot 20. Between its remaining surface and the base wall of the slot 20 a gap is left, so that a space 22 is formed. This space continues from the base of the slot 20 for the length of the outer side wall up to the top edge of the slot, where it opens outwards via a gap 24.

The base wall of the slot 20 is provided with knurling or grooving 26, which is arranged opposite to similarly constructed knurling or grooving 28 on the facing surface of the retaining web 18. This knurling or grooving 26,28 forms recesses and peaks respectively which protrude into the space 22.

A defined position of the section rail 14 relatively to the section part 12 is achieved by providing, on the rail and running longitudinally thereof, an anchoring element 30 which is hook shaped in cross section and which is engaged with a complementary anchoring slot 32. The anchoring can take place through snap-in engagement or by a locking seat.

After the section rail 14 is inserted into the slot 20 and is anchored to the section part 12 by snapping in or by a locking seat, the space 22 is filled with a filler, for which purpose a thermally insulating casting resin of high mechanical strength is preferably used: The so-called one- or two-component adhesives are suitable although they are not in this instance used, however, for their adhesive properties but rather for their capability of forming a positive, rigid and mechanically resistant joint. With the construction illustrated, the filling compound or filler can be inserted through the gap 24.

The embodiment shown in Figures 6 and 7 distinguishes itself by especially simple handling of the section parts to be joined together by the section rail.

The slot 20 is of normal right-angle shape in cross section and has in the middle of its base wall a projecting anchoring strip 34, running longitudinally and with a thickening 36 at its free longitudinal edge.

On the outside edges of the slot walls, inwardly directed projections 38,40 are provided by which the filler is secured in the slot after hardening. The retaining web 18 has on its free ends two expanding shanks 42,44, separated from each other by a slit 40 and which are elastically deformable. This slit 40 is formed so that in the expanded condition of the shanks 42,44 it is complementary in shape to the shape of the anchoring strip 34 with its thickening 36.

The section rail 14, in Figure 6, is pressed on to the anchoring strip in the direction indicated by the arrow 46, until it reaches the position shown in Figure 7 and is firmly engaged on to the anchoring strip 34. The expandable shanks 42,44 are thus expanded. The grooving or knurling 26,28 are formed on the thickening 36 and on the parallel surface of the retaining web 18, being the base wall of the slot 20, respectively.

With the embodiment shown in Figure 7, the filler can be inserted in the space 22 in advance or inserted after the placing of the section rail 14 on the anchoring strip 34.

With the embodiment shown in Figure 8, the slot 20 has, on both of its side walls, bulging recesses 48, 50 running longitudinally of the slot, and similarly formed recesses 52, of the retaining web 18 lie opposite thereto. These recesses 48, 52 and 50, 54, respectively, form in cross section cores of similar - appearance which extend longitudinally and are subsequently filled with filler. The knurling orgrooving 26,28 is provided on the base wall of the groove and the facing surface of the retaining web 18, respectively.

With the embodiment shown in Figure 9 the outer side wall of the slot 20 is constructed as a deformable shank 56. The form of the retaining web 18 is similar to that in Figures 1 to 5 but only a longitudinally extending stop lug 58 is provided instead of the anchoring elements. Further, the retaining web 18 has a longitudinally extending rib 60 facing the deformable shank 56, which can engage in a corresponding groove 62 of a thickened edge 64 of the shank 56. With the construction shown in in Figure 9, the shank 56 is easily bent outwards so that the slot is extended in order to facilitate insertion of the retaining web 18.After the retaining web is engaged with the stop lug 58 lying against the section part 12, the deformable shank 56 is brought into the position shown in Figure 10, in which it is pressed against the section rail 14 and the retaining web 18 respectively.

The pressing against takes place, however, only so far as until the rib 60 engages in the groove 62, without an excessive stress being exerted on the retaining web 18. With this embodiment the knurling or grooving 26,28 are, respectively, provided at the same position as in the embodiment of Figures 1 to 5.

After the retaining web 18 is inserted in the groove 20 and the deformable shank is pressed against the retaining web 18 in the manner shown in Figure 10, the space 22 is filled with filler. With this embodiment, it is intended to fill with the filler from the end into the space 22 over the whole length of the composite section. With the use of a suitable filler this can be achieved over very long lengths of many metres.

The embodiment of Figures 11 and 12 likewise has a deformable shank 56. However, it differs in the construction of the slot 20 and the retaining web from the embodiment of Figures 9 and 10. With the embodiment of Figures 11 and 12 the retaining web 18 has two longitudinally extending grooves 66,68 which lie opposite one another, being disposed either symmetrically or staggered. In these grooves 66, 68 engage correspondingly formed ribs 70,72 on the outer longitudinal edges of the slot 20, with the rib 72 formed on the free end of the deformable shank. The extended position of the deformable shank 56 is shown in broken lines in Figure 11.

With the embodiment of Figure 11 the filler is again introduced from the end.

With the embodiment of Figure 12, the base wall of the slot 20 has a groove 74 which serves to receive a filler which hardens with volume increase. This filler can easily be introduced into the groove and subsequently fills by hardening, thus occupying the whole space 22.

With the embodiment shown in Figures 13 and 14 the groove 20 is of generally rectangular form and is constricted on its open side by inwardly projecting wall parts 76,78. The retaining shank 18 of the section rail 14 has two expanding shanks 82, 84 separated from each other by a slit 80 and having,on their outer sides, stop lugs 86. 88 to engage behind the wall parts 76,78. The open end of the slit 80 opens into an acceptance groove SO which is intended to accept a filler, which hardens with increase in volume. The filler is introduced into the acceptance groove SO before the insertion of the retaining web 18 in the slot 20. With hardening the filler expands to a considerable extent, the expanding shanks 82,84 being expanded away from each other and the whole of the space 22 being filled.Thereby the stop lugs 86, 88 engage behind the wall parts 76,78.

The knurling and grooving, 26, 28 respectively, is provided on the base wall of the slot 20 and on the facing surface of the retaining web 18 respectively.

A feature common to all the described embodiments is that no stresses are exerted in the unstressed condition on the joint formed by the parts, so that there is no fear of any deterioration in the tensile strength or shear strength of the joint, as a result of subsequent surface treatment at high temperatures, such as anodic treatment, stoving, varnishing, and the like, for example as a result of plastic flow.

Further, an absolutely sealed joint between the plastics rail and the section parts is obtained, so that with anodic treatment or varnishing no washing problems arise because of small cavities or capilliary cracking.

Reforming work is completely eliminated with the embodiments of Figures 1 to 8, 13 and 14, and is restricted to a small amount with the embodiments of Figures 9 and 10 and Figures 11 and 12,respec- tively, which excludes all danger of deformation of the section parts. Thus exceptionally good size accuracy of the composite section results.

Claims

1. A composite section comprising two section parts joined in the longitudinal direction of the section parts by at least one thermally insulating section rail having anchored retaining webs which extend longitudinally in slots in the section parts, wherein -the retaining webs of the section rail are provided with a series of peaks and recesses, at right angles to the longitudinal direction, -the slots have at least one inner surface which likewise is provided with a series of peaks and recesses, at right angles to the longitudinal direction, - between the retaining webs and limiting wall parts of the slots a space is formed into which the peaks extend, and -said space is filled with a preferably thermally insulating and mechanically strong filler which provides a positive connection between the retaining webs and the slots.

2. A composite section according to claim 1, wherein the peaks and recesses of the retaining webs and slots are, respectively, arranged opposite to each other.

3. A composite section according to claim 1 or 2, wherein the section rail is inserted longitudinally in an undercut formed slot.

4. A composite section according to any one of the preceding claims, wherein the section rail and the section parts have complementary anchoring elements for attaching the section rail to the section parts, using locking seats.

5. A composite section according to any one of the preceding claims, wherein the peaks and recesses are respectively formed by knurling and grooving.

6. A composite section according to any one of the preceding claims, wherein the filler is a hardenable casting resin.

7. Acomposite section according to claim 6, wherein the filler is a two-component casting resin.

8. A composite section according to any one of claims 1 to 5, wherein the filler is one of the volumeincreasing age-hardenable filler compounds.

9. A composite section according to any one of the preceding claims, wherein the dimensions of the retaining webs on the one hand, and of the slots on the other hand, are so chosen that the retaining webs can be inserted in the slots at right angles to the longitudinal direction.

10. A composite section according to any one of the preceding claims, wherein the section rail, after insertion of a retaining web into a slot, has at least one surface fitting against a correspondingly formed section part surface, and by this is located in a definite position in relation to that section part.

11. A composite section according to any one of the preceding claims, wherein the section rail is a flat section, on the edges of which the retaining webs are formed.

12. A composite section according to any one of the preceding claims, wherein the section rail has a longitudinal anchoring element, hook-shaped in cross section, which engages in a suitably formed anchoring slot of the section parts.

13. A composite section according to any one of the preceding claims, wherein the section track is of C-shaped form and the outer limbs of the "C" are formed by the retaining webs.

14. A composite section according to any one of the preceding claims, wherein the slot has a projecting anchoring strip extending longitudinally along the base of the slot and with a thickening at its free end, the section rail has on its retaining web a connecting slot which is of complementary form with respect to the anchoring strip, and expanding shanks between which the slot is formed are flexibly deformable.

15. A composite section according to any one of the preceding claims, wherein the slots have on the side walls thereof at least one undercut recess which lies opposite to a recess in a retaining web.

16. A composite section according to claim 15, wherein each recess in a side wall of a slot, and the corresponding recess in a retaining web, combine in cross section to form a core.

17. A composite section according to claim 15 or 16, wherein one of said recesses is provided in each of the side walls of the slot and, correspondingly, on each side of the retaining web.

18. A composite section according to any one of the preceding claims, wherein the slots are expanded for easier insertion of the retaining web and have a deformable shank which, after the insertion of a retaining web, can be pressed against the inserted web.

19. A composite section according to claim 18, wherein said deformable shank has a backing slot extending longitudinally and into which, after said pressing against the web of the shank, a com plementarily formed backing rib of the section rail engages.

20. A composite section accordig to claim 18 or 19, wherein the section rail is firmly fixed as a result of the shank being pressed against it, with only slight stress in the section parts.

21. A composite section according to any one of claims 1 to 12, wherein the section rail is of I-shaped form in cross section, and the retaining webs are formed by the end limbs of the "I".

22. A composite section according to any one of the preceding claims, wherein the section rail has at least one longitudinally extending stop lug which limits the depth of insertion of the retaining web in the slot.

23. A composite section according to any one of claims 1 to 12, wherein the retaining webs have a slit to provide two deformable separate expanding shanks, between which a pick-up groove is provided for picking up a filler which is age-hardenable with increase in volume.

24. A composite section according to claim 23, wherein on the expanding shanks a longitudinally extending lug is provided, which can be engaged behind an undercut limiting wall of the slot.

25. A composite section, constructed and arranged substantially as herein particularly described with reference to Figures 1 to 5, Figures 6 and 7, Figure 8, Figures 9 and 10, Figures 11 and 12, or Figures 13 and 14, of the accompanying drawings.