EP2754778A1 - Primary support beam with adjustable length - Google Patents

Abstract

The beam (1) has secondary beams whose intermediate fixing unit (3) is fixedly placed on an intermediate section (4) of a central core (2). Sleeves (5, 6) include fixing units (7, 8) of secondary beams mounted on end sections (20a, 20b) of the core to slide on the core toward and away from the intermediate fixing unit. The fixing units extend laterally and longitudinally along the intermediate section and along the sleeves. The intermediate fixing unit is carried by a third sleeve (11). The third sleeve has a cross-section identical to that of the sleeves. An independent claim is also included for a support structure of a formwork of slab.

Description

The present invention relates to a primary support beam for slab formwork or the like, and more particularly relates to a primary support beam with adjustable length.

Of the document FR 2 794 155 A1 a support beam is known for the construction of lintels by formwork. This beam has an adjustable length through two elements slidably mounted one in the other. To do this, one of the elements has a cross section much lower than the other elements, so as to be received and contained in the latter.

The beam of the document FR 2 794 155 A1 is devoid of means for the attachment of secondary beams over its entire length, especially when it is deployed at maximum length. This beam is not usable as primary support beam for slab formwork or the like. The formwork of a slab or the like indeed requires the joining together of a plurality of primary beams by means of secondary beams serving as spacers between said primary beams.

Another disadvantage of the beam of the document FR 2 794 155 A1 is that, because of the very different cross-sections of its two constituent elements, its flexural behavior under load is not easily predictable and computable, especially since this behavior varies according to the more or less important deployment of the length of the beam.

The document US 2010/0071141 A1 discloses a primary support beam according to the preamble of claim 1.

The document US 3,993,282 A discloses a beam with sliding end sleeves, but which has no attachment means for secondary beams, and whose central core has no cross section identical to those of the sliding end sleeves.

A first problem proposed by the invention is to provide a primary support beam for slab formwork or the like, having an adjustable length in order to reduce the primary beam references to be held in stock by the supplier of slab formwork material or the like. .

Simultaneously, the invention aims to provide a primary beam whose adjustability in length as little as possible hinders the need for attachment of secondary beams for the formation of a support structure for slab formwork or the like, while providing a management and simplified use of secondary beams.

According to another aspect, the invention aims to design a primary beam with flexural behavior under load allowing a possible reinforcement by the provision of props in a simple and intuitive way, without having to make calculations of resistance too complicated.

• des moyens intermédiaires d'accrochage de poutrelles secondaires, disposés de façon fixe sur un tronçon intermédiaire de l'âme centrale,
• des premier et deuxième manchons, comportant chacun des premiers ou deuxièmes moyens d'accrochage de poutrelles secondaires respectifs et des premier ou deuxième nez d'accrochage respectifs, montés respectivement à coulissement selon la direction longitudinale sur des premier et deuxième tronçons d'extrémité de l'âme centrale de façon à pouvoir coulisser sur l'âme centrale de part et d'autre, vers et à l'écart, des moyens intermédiaires d'accrochage de poutrelles secondaires ;

selon l'invention :

• les moyens intermédiaires d'accrochage de poutrelles secondaires et les premiers et deuxièmes moyens d'accrochage de poutrelles secondaires s'étendent respectivement latéralement et longitudinalement le long du tronçon intermédiaire de l'âme centrale et le long des premier et deuxième manchons,
• les moyens intermédiaires d'accrochage de poutrelles secondaires sont portés par un troisième manchon,
• le troisième manchon présente une section transversale identique à celle des premier et deuxième manchons.

To achieve these and other objects, the invention provides a primary support beam for slab formwork or the like, comprising a central core extending in a longitudinal direction between a first end and a second end, comprising:

• intermediate means for attaching secondary beams, arranged in a fixed manner on an intermediate section of the central core,
• first and second sleeves, each comprising first or second attachment means of respective secondary beams and respective first or second attachment noses respectively slidably mounted in the longitudinal direction on first and second end sections of the central core so as to slide on the central core on both sides, towards and away, intermediate means for attaching secondary beams;

according to the invention:

• the intermediate means for attaching secondary beams and the first and second means for attaching secondary beams extend respectively laterally and longitudinally along the intermediate section of the central core and along the first and second sleeves,
• the intermediate means of attachment of secondary beams are carried by a third sleeve,
• the third sleeve has a cross section identical to that of the first and second sleeves.

Such a beam has an adjustable length by sliding of the first and second sleeves on the central core. This allows the slab formwork equipment supplier or the like to significantly reduce the number of primary beam references to be available in stock, the length of each primary beam can be adjusted to several particular situations encountered by the masons.

The central core and each of the first and second sleeves being provided with means for attaching secondary beams, as little as possible is prevented the need for attachment of secondary beams for the assembly of a slab formwork structure or the like.

It is also possible to partially partially slide, on either side of the intermediate section, each of the first and second sleeves to adjust the total length of the primary beam, way that the bending behavior of the primary beam is symmetrical on both sides of the intermediate section of the central core. Calculations of flexural strength under load are thus greatly facilitated, as well as the positioning of possible struts for reinforcing the primary beam. The positioning of the props will in fact be substantially symmetrical and therefore relatively simple and intuitive by the operators on the site.

The third sleeve allows the primary beam to have a substantially identical cross section along its length when at its minimum length with the first and second sleeves with maximum overlap of the central core. In addition, the primary beam and has along its length a plurality of support zones located at the same level to allow a setting at the same level of elements (such as plates) slab formwork or the like.

In addition, the first, second and third sleeves can be used identically for lateral attachment of secondary beams, the latter can therefore have a single length. The management and use of secondary beams are thus simplified.

Finally, the primary beam thus has a relatively constant axial moment of inertia along its entire length.

Advantageously, the intermediate means of attachment of secondary beams and the first and second attachment means of secondary beams may comprise side channels receiving secondary beam.

There are thus easily accessible, simple and quick to use secondary beam attachment means: the attachment of a secondary beam is made by a simple translational movement simultaneously causing a commitment of the secondary beam in the lateral receiving chutes two primary beams arranged apart from each other.

Preferably, during the sliding of the first and second sleeves, the first and second attachment means of secondary beams can be respectively distant intermediate means of attachment of secondary beams of at most about 20 cm.

It allows the attachment of secondary beams on the primary beam at a distance of up to 20 cm, which greatly limits the risk of a man falling between two adjacent secondary beams.

Preferably, the primary beam may comprise locking means of the first and second sleeves on the central core.

Such locking means, although they are not necessarily necessary when the primary beam is assembled within a formwork support structure, nevertheless facilitate the handling and installation of the primary beam by avoiding inadvertent sliding of the beams. first and second sleeves on the central core.

• des trous dans l'âme centrale et au moins un trou dans chacun des premier et deuxième manchons, disposés de façon à pouvoir venir en correspondance par coulissement des premier et deuxième manchons sur l'âme centrale,
• des goupilles aptes à pénétrer simultanément dans un trou d'un premier ou deuxième manchon et dans un trou de l'âme centrale en correspondance.

Preferably, the locking means may comprise:

• holes in the central core and at least one hole in each of the first and second sleeves, arranged to slidably connect the first and second sleeves on the central core,
• pins capable of simultaneously penetrating into a hole of a first or second sleeve and into a corresponding hole in the central core.

Such locking means are simple, easy to use, robust and relatively well protected from shocks that can occur in the external environment.

• la figure 1 est une vue en perspective d'une poutrelle primaire selon un mode de réalisation particulier de l'invention, ladite poutrelle primaire présentant une longueur minimale ;
• la figure 2 est une vue en perspective de la poutrelle primaire de la figure 1 présentant une longueur ajustée maximale ;
• la figure 3 est une vue en coupe transversale de la poutrelle primaire des figures 1 et 2 ; et
• la figure 4 est une vue en perspective de la poutrelle primaire de la figure 2 lors de son utilisation avec des poutrelles secondaires pour former une structure de coffrage de dalle ou analogue.

Other objects, features and advantages of the present invention will become apparent from the following description of particular embodiments, with reference to the accompanying figures, in which:

• the figure 1 is a perspective view of a primary beam according to a particular embodiment of the invention, said primary beam having a minimum length;
• the figure 2 is a perspective view of the primary beam of the figure 1 having a maximum adjusted length;
• the figure 3 is a cross-sectional view of the primary beam of figures 1 and 2 ; and
• the figure 4 is a perspective view of the primary beam of the figure 2 when used with secondary beams to form a slab formwork structure or the like.

The figures 1 and 2 illustrate a particular embodiment of primary support beam 1 according to the invention. On the figure 1 , the primary beam 1 has a total length L1 minimum while on the figure 2 , the primary beam 1 has a total length L2 maximum. The total length of the primary beam 1 is thus adjustable between the lengths L1 and L2 to suit the different situations that masons may encounter on a construction site.

• des moyens intermédiaires d'accrochage de poutrelles secondaires 3, disposés de façon fixe sur un tronçon intermédiaire 4 de l'âme centrale 2,
• des premier 5 et deuxième 6 manchons, comportant chacun des premiers 7 ou deuxièmes 8 moyens d'accrochage de poutrelles secondaires respectifs et des premier 9 ou deuxième 10 nez d'accrochage respectifs.

To do this, the primary beam 1 comprises a central core 2 extending in a longitudinal direction II between a first end 2a and a second end 2b ( figure 2 ). The primary beam 1 also comprises:

• intermediate means for attaching secondary beams 3, fixedly arranged on an intermediate section 4 of the central core 2,
• first and second sleeves 5, each having first 7 or second 8 attachment means of respective secondary beams and the first 9 or second 10 hooking nose respectively.

The sleeves 5 and 6 are respectively slidably mounted in the longitudinal direction II on first 20a and second end portions 20b of the central core 2 so as to slide on the central core 2 on both sides, towards and away, intermediate means for attaching secondary beams 3.

In particular, as it is more particularly visible on the figure 2 , the intermediate means of attachment of secondary beams 3 are carried by a third sleeve 11 fixed on the central core 2 by rivets 23.

The third sleeve 11 has a cross section identical to that of the first 5 and second 6 sleeves.

This cross section, common to the first 5, second 6 and third 11 sleeves, is illustrated in more detail on the figure 3 .

On said figure 3 it can be seen that the intermediate means for attaching secondary beams 3 and the first 7 and second 8 means for attaching secondary beams comprise side receiving troughs 12a, 12b of secondary beams, respectively extending longitudinally along the section intermediate 4 of the central core 2 and along the first 5 and second 6 sleeves.

We see more particularly on the figure 4 that the lateral receiving chute 12a is shaped so as to receive in abutment hooking noses 13 of secondary beams 14a to 14h. It is the same for the lateral receiving chute 12b.

The hooking noses 13, as well as the attachment noses 9 and 10, have a hook-shaped lower structure engaging in the chute 12a.

The bottom 15 of the lateral receiving chute 12a allows the support of the secondary beams 14a to 14h on the primary beam 1, while the raised wing 16 of the lateral receiving chute 12a opposes the withdrawal of the secondary beams 14a to 14h away from the primary beam 1 according to a translational movement illustrated by the arrow 24.

At their other end, the secondary beams 14a to 14h are also provided with attachment noses 13 engaged in a lateral receiving chute 12b of another primary beam 1 so as to maintain the two primary beams 1 at a spacing distance constant throughout their length.

We see more particularly on the figure 2 that, during the sliding of the first 5 and second 6 sleeves, the first 7 and second 8 securing means of secondary beams are respectively distant intermediate means of attachment of secondary beams 3 by a distance d of at most about 20 cm.

We also distinguish on this figure 2 that the primary beam 1 comprises locking means 17 of the first 5 and second 6 sleeves on the central core 2.

• une pluralité de trous 18 dans l'âme centrale 2 et au moins un trou 19 dans chacun des premier 5 et deuxième 6 manchons, les trous 18 et 19 étant disposés de façon à pouvoir venir en correspondance lors du coulissement des premier 5 et deuxième 6 manchons sur l'âme centrale 2,
• des goupilles 20 aptes à pénétrer simultanément dans un trou 19 d'un premier 5 ou deuxième 6 manchon, et dans un trou 18 de l'âme centrale 2 en correspondance.

In this case, the locking means 17 comprise:

• a plurality of holes 18 in the central core 2 and at least one hole 19 in each of the first 5 and second 6 sleeves, the holes 18 and 19 being arranged to be able to come into correspondence during the sliding of the first 5 and second 6 sleeves on the central core 2,
• pins 20 able to penetrate simultaneously into a hole 19 of a first 5 or second 6 sleeve, and into a hole 18 of the central core 2 in correspondence.

In the embodiment illustrated on the figures 1 and 2 the pins 20 are in fact bolts consisting of a screw 21 and a nut 22.

When the holes 19 of the first 5 or second 6 sleeves are arranged in correspondence of holes 18 of the central core 2, the screws 21 are engaged transversely through the sleeves 5 and 6 and the central core 2, and the nut 22. is screwed onto the threaded free end of the screw 21 protruding out of the sleeves 5 and 6.

After engagement of the screws 21 through the sleeves 5 and 6 and the central core 2, any sliding of the sleeves 5 and 6 is prevented.

The use of primary beams 1 for the assembly of a support structure for slab formwork or the like will now be explained in more detail.

First, the primary beam 1 is in the configuration illustrated on the figure 1 in which it has a total length L1 minimum. The storage of the primary beam 1 and the transport are thus facilitated.

If the total length L1 satisfies the use envisaged on the site, the operator keeps the primary beam 1 with a total length L1 and fixes the hooking noses 9 and 10 on two walls distant from each other. a distance equal to or slightly greater than the total length L1.

The operator then installs another identical primary beam 1 on the two walls, this primary beam 1 being located at the same height and parallel to the first primary beam 1. During this operation, the operator arranges the primary beams 1 to one distance from one another corresponding to the length of the secondary beams 14a to 14h.

The operator then presses the secondary beams 14a to 14h on the primary beams 1 by engaging the attachment noses 13 in the lateral receiving chutes 12a and 12b. The secondary beams 14a to 14h have the same length, which facilitates their use and management of their stock.

Finally, the operator has a formwork plate resting on the top of the primary beams 1 and the secondary beams 14a to 14h by a simple substantially vertical translation movement illustrated by the arrow 25 on the figures 3 and 4 .

If the total length L1 of the primary beam 1 is not suitable for the intended use, the operator removes the locking means 17 to increase the length of the primary beams 1 to the total length L2 if necessary. Once the length of the primary beams 1 adjusted, the operator can reinstall the locking means 17. The locking means 17 are however not mandatory from the moment when the attachment noses 9 and 10 are properly secured to the walls.

In the same way as before, the operator installs another primary support beam 1 away from the primary beam 1, and then, as illustrated in FIG. figure 4 , it has a plurality of secondary beams 14a to 14h by engaging the attachment noses 13 of the latter in the lateral receiving chutes 12a and 12b of the primary beams 1.

On the figure 4 , it is observed that the secondary beam 14c is engaged in the lateral receiving trough 12a (and 12b, not visible) of the first sleeves 5, while the secondary beams 14d and 14e are engaged in the lateral receiving trough 12a (and 12b, not visible) of the third sleeves 11, and that the secondary beam 14f is engaged in the lateral receiving trough 12a (and 12b, not visible) of the second sleeves 6.

The distance between the secondary beams 14c and 14d, or 14e and 14f on the one hand, and between the secondary beams 14e and 14f on the other hand, is at most about 20 cm to limit the risks that a man falls between the beams 14c and 14d, 14d and 14e, or 14e and 14f.

When adjusting the length of the primary beam 1, the operator can judiciously slide identically the first 5 and second 6 sleeves away from the intermediate portion 4 of the central core 2 and thereafter , install the secondary beams 14a to 14h symmetrically on either side of the middle of the intermediate section 4.

The load to which the primary beam 1 is then subjected will thus be resumed symmetrically on either side of the middle of the intermediate section 4, which facilitates the prediction of its flexural load behavior and the rapid and intuitive layout of the props to help the primary beam 1 support the load if needed.

In the support structure for slab formwork or the like illustrated on the figure 4 , the upper faces 5a, 6a and 11a of the sleeves 5 and 6 and the intermediate section 4 are at the same level, which also corresponds to the level at which the upper faces 22a to 22h of the secondary beams 14a to 14h. It is thus possible to have a formwork plate on the primary beam 1 and the secondary beams 14a to 14h on one and the same plane.

The present invention is not limited to the embodiments which have been explicitly described, but it includes the various variants and generalizations thereof within the scope of the claims below.

Claims (6)

Primary support beam (1) for slab formwork or the like, comprising a central core (2) extending in a longitudinal direction (II) between a first end (2a) and a second end (2b), comprising: intermediate means for attaching secondary beams (3), arranged in a fixed manner on an intermediate section (4) of the central core (2), first (5) and second (6) sleeves, each comprising first (7) or second (8) means for attaching respective secondary beams and respective first (9) or second (10) gripping noses, respectively slidably mounted in the longitudinal direction (II) on first (20a) and second (20b) end sections of the central core (2) so as to be slidable on the central core (2) from on the other hand, towards and away, intermediate means for attaching secondary beams (3), characterized in that the intermediate means for attaching secondary beams (3) and the first (7) and second (8) means for attaching secondary beams to respectively extend laterally and longitudinally along the intermediate section (4) of the core; central (2) and along the first (5) and second (6) sleeves, the intermediate means for attaching secondary beams (3) are carried by a third sleeve (11), - The third sleeve (11) has a cross section identical to that of the first (5) and second (6) sleeves. Primary support beam (1) according to claim 1, characterized in that the intermediate means for attaching secondary beams (3) and the first (7) and second (8) means for attaching secondary beams comprise lateral chutes. receiving beam (12a, 12b). Primary support beam (1) according to one of claims 1 or 2, characterized in that , during the sliding of the first (5) and second (6) sleeves, the first (7) and second (8) means of attachment of secondary beams are respectively distant intermediate means of attachment of secondary beams (3) of at most about 20 cm. Primary support beam (1) according to any one of claims 1 to 3, characterized in that it comprises locking means (17) of the first (5) and second (6) sleeves on the central core (2). ). Primary support beam (1) according to one of Claims 1 to 4, characterized in that the locking means (17) comprise: holes (18) in the central core (2) and at least one hole (19) in each of the first (5) and second (6) sleeves, arranged to be slidably connected to the first (5) and second (6) sleeves (5); ) and second (6) sleeves on the central core (2), - Pins (20) able to simultaneously enter a hole (19) of a first (5) or second (6) sleeve and into a hole (18) of the central core (2) in correspondence. Support structure for slab formwork or the like, characterized in that it comprises: a plurality of primary support beams (1) according to any one of claims 1 to 5, said primary beams (1) of support being identical to each other, - A plurality of secondary beams (14a-14h) identical to each other at least in length.

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