WO2006108495A1

WO2006108495A1 - System for the coupling of a support strut to a formwork table

Info

Publication number: WO2006108495A1
Application number: PCT/EP2006/002520
Authority: WO
Inventors: Pedro Xammar Bobe
Original assignee: Inveral, S.A.
Priority date: 2005-04-12
Filing date: 2006-03-20
Publication date: 2006-10-19
Also published as: ES2297968A1; ES2297968B1

Abstract

System for the coupling of a strut (10) to a formwork table consisting of longitudinal beams (3) and cross beams (4). The system comprises a support part (2) which can be fixed to the upper end of the strut, provided with a support plate (5), attachment means (6) and retaining means (7) whereby the strut is oscillatably suspended from two adjacent longitudinal beams and is retained in a working position perpendicular thereto respectively. The pair of beams is provided with a group of two suspension bars (8, 8') which extend perpendicularly so that the first and second suspension bars are adapted to receive, respectively the coupling the attachment means and of the retaining means, or vice-versa. With the strut retained in the working position, the support plate receives the direct support of said adjacent longitudinal beams.

Description

D E S C R I P T I O N

SYSTEM FOR THE COUPLING OF A SUPPORT STRUT TO A FORMWORK TABLE

Technical field of the invention

The invention relates to a system for the coupling of a support strut to a formwork table of the type used in the construction of floors in building construction, basically composed of a horizontal structure formed by a framework of longitudinal beams and cross beams covered at its upper part with boards.

Background of the invention

The use of formwork tables for the formation of floors is becoming an increasingly common practice in building construction. Formwork tables constitute a quick, convenient way of forming a floor structure, as they are relatively light and easy to transport.

Basically, a formwork table comprises a horizontal structure formed by a framework of metal or wooden longitudinal beams and cross beams, whereon a series of boards rests to form the formwork structure. This horizontal structure is conventionally supported by several struts or by centres removably coupled to the formwork table.

EP 0945564 B1 discloses a formwork table which comprises a framework of beams supported by struts pivotably coupled thereto. To couple the struts to said framework, a support part is positioned on the heads thereof which can be coupled in turn to a counter-support part preferably mounted on the lower part of the formwork table. The support part or the counter-support part are provided with suspension means and blocking means, consisting of a series of tabs or hooks which fit into corresponding orifices provided for said purpose in the other part. These suspension means enables the support part to be connected to the counter-support part in an oscillatable manner, both parts being able to separate easily. For their part, the blocking means are responsible for maintaining the support part joined to the counter-support part in a fixed working position, wherein the struts are in their normal position with respect to the formwork table. The support part comprises a rectangular support plate whereon the formwork table rests in the working position via the corresponding plate which the counter-support part is provided with. In the formwork table system disclosed, the suspension means permits that the support part is joined to the counter-support part so that the former is suspended from the latter. Furthermore, according to this arrangement, from the construction elements of the counter-support part, only the lowest part, its rectangular support plate, is below the beams.

According to this system, the counter-support part is suspended from two adjacent cross beams by straps and it is fixed on its lower part to the formwork table externally gripping the two profiles which compose a longitudinal beam. The aforementioned shows the complexity of said counter-support part necessary to couple the support part of a strut head to the formwork table and the consequent weight that each of the counter-support parts provide to the table.

Another formwork table system is disclosed in DE 20318912 U1 , wherein the formwork table comprises at least two steel beams slightly separated from one another and provided with regularly distanced perforations throughout its length whereby the struts are connected to the formwork table by placing connection heads which can be coupled to the struts in the perforations.

The connection head is provided on its upper part with perforations coinciding with those of the beams, allowing it to be secured to the table, positioning it between the two steel beams and inserting movable pins in the perforations of the beams and the head. On positioning two movable pins, the head may remain in an oscillating position with respect to the beams. In this system, the strut is fixed to the connection head preventing any relative movement between this and the strut, as it is the connection head which rotates with respect to the steel beams. Furthermore, each connection head is provided with a catch whereby the struts can be blocked in two determined rotating positions or blocked in the working position of the struts.

Although blocking the struts in the rotation positions determined by the catch facilitates that at a certain time the struts are partially folded on the table, for example, when manoeuvring work has to be performed under the formwork table which requires a certain freedom of movement without being hindered by the struts, the mounting of the struts on the connection heads is complicated. To fix the struts, the connection heads are provided on their lower part with a profile with the lower end open and wherein two of their opposing sides are provided with coincident through-holes. The upper end of the strut is inserted through the open lower end of said profile, which strut is topped by a small plate, and then wedges are inserted in each of the two through-holes of one side, wedges which traverse the profile until protruding from the orifices of the opposite face, so that these wedges support the lower part of small plate which tops the upper end of the strut. These assembly tasks require more time and effort by the operator as it is essential that he/she insert said wedges with the aid of a tool to fix the strut to the connection head.

From the aforementioned systems for the coupling of struts to a formwork table, the need is shown for a system which simplifies the work of mounting, coupling and decoupling of the struts to said table.

Explanation of the invention

The system for the coupling of a support strut to the horizontal structure of a formwork table, object of the invention, is designed for tables whose horizontal structure consists of longitudinal beams and cross beams. Said system comprises a support part which can be fixed to the upper end of the strut, of the type provided with a support plate perpendicular to the strut, attachment means and retaining means whereby the associated strut can remain suspended from the horizontal structure with the capacity for oscillation with respect thereto and of being retained in a working position essentially perpendicular thereto respectively.

In essence, the system for the coupling of a support strut to the horizontal structure of a formwork table is characterized in that said horizontal structure comprises at least one pair of adjacent longitudinal beams provided with at least one group of two suspension bars which extend perpendicular to the direction of the longitudinal beams so that the first and second suspension bars are adapted to receive, in their end portions, respectively the coupling of the attachment means and the retaining means, or vice-versa, of the support part, and in that when the strut is retained in the working position, the support plate of the support part receives the direct support of said pair of adjacent longitudinal beams.

According to a characteristic of the invention, the support plate of the support part is provided with two margins which extend parallel to the direction of the longitudinal beams and which are positioned at a level above that of the remainder of the support plate.

In accordance with another characteristic of the invention, the two suspension bars are solidly fixed to the undersides of two adjacent longitudinal beams, these suspension bars being positioned immediately below said longitudinal beams.

In accordance with another characteristic of the invention, the two suspension bars are integrated in a counter-support part, removably fixed to the two adjacent longitudinal beams of the formwork table, which comprises a spacing body designed to be housed between these longitudinal beams, said spacing body being provided with suspension and tightening means whereby said spacing body is stably suspended from the topside of said longitudinal beams, said suspension bars being positioned immediately below them.

According to another characteristic of the invention, the suspension and tightening means comprise at lest one vertical screw rod arranged on the longitudinal axis of the spacing body and corresponding set nut and washer for the upper fixing of the counter-support part to the longitudinal beams, the suspension bars acting as lower limit against said beams.

In accordance with another characteristic of the invention, the suspension and tightening means comprise at least one hand-rail with a window disposed on the longitudinal axis of the spacing body and the corresponding wedge for the upper fixing of the counter-support part to the longitudinal beams, the suspension bars acting as lower limit against said beams.

In accordance with another characteristic of the invention, the support part comprises two side plates, separated from one another by the support plate whereto they are joined perpendicularly, and the attachment means of the support part comprises at least two hooks each one fixed to one of the upper ends of the inner sides of the of the opposing side plates.

According to another characteristic of the invention, the retaining means of the support part comprise at least two clasp hooks each provided with prolongations pivotably joined to the other upper ends of the inner sides of the opposing side plates opposite those provided with hooks.

In accordance with another characteristic of the invention, the support part laterally comprises an adjustment plate and an adjustment structure provided with at least two studs, between which the upper end of the strut is confined and fitted when said studs traverse the adjustment plate and corresponding nuts are screwed in its ends.

In accordance with another characteristic of the invention, between the adjustment plate of the support part and the strut is arranged an intermediate part made of material compressible in the event of impacts, capable of absorbing the impacts generated between the strut and the support part.

According to another characteristic of the invention, the intermediate part is made of a flexible material.

Brief description of the drawings

The attached drawings illustrate, by way of non-limiting example, a preferred embodiment of the system for the coupling of a support strut to the horizontal structure of a formwork table object of the invention. In said drawings:

Fig. 1 is a perspective view of a particular embodiment of the counter- support part of the system object of the invention;

Fig. 2 is a side view of the counter-support part of Fig. 1 removably fixed to two longitudinal beams;

Fig. 3 is a perspective view of a formwork table with the counter- support part of Fig. 1 ; Fig. 4 is a detailed view of Fig. 3;

Fig. 5 is a front view of the counter-support part of Fig. 1 suspended from a longitudinal beam;

Fig. 6 is a front view of a strut in an oscillating position with respect to the counter-support part of Fig. 1 ;

Fig. 7 is a front view of the strut of Fig. 6 in working position;

Fig. 8 is a perspective view of the exploded assembly of a support part on the head of a strut;

Fig. 9 is a perspective view of the support part of Fig. 8;

Fig. 10 is another perspective view of the support part of Fig. 8;

Fig. 11 is a perspective view of the support part of Fig. 8 seen from below; and Fig. 12 is a plan view of the support part of Fig. 8 seen from below.

Detailed description of the drawings

As is observed in Fig. 3, the formwork tables used for the construction of floors are basically formed by a horizontal structure of longitudinal beams 3 and cross beams 4 supported by a series of struts 10 which can be coupled to the table. The boards 51 which constitute the lower surface of the formwork of the floor to concrete rest on the cross beams 4.

Figs. 3 and 4 have represented a formwork table with metal longitudinal beams 3 and cross beams 4. In particular, the longitudinal beams 3 represented are C-shaped cross-section metal longitudinal beams and are grouped two by two, slightly separated from one another. The system used so that the struts 10 of Fig. 3 are coupled to the horizontal structure of the formwork table is made via a support part 2 which can be coupled to the head of the strut 10 and a group of two suspension bars 8 and 8', represented with cylindrical shape, which extend perpendicular to the direction of the longitudinal beams 3. The two suspension bars 8 and 8' may be solidly joined to the undersides of two adjacent longitudinal beams 3, for example, by welding. Another option is that the two suspension bars 8 and 8' are integrated in a counter-support part 1 which can be removably fixed to the horizontal structure of the formwork table, and in particular, to two adjacent longitudinal beams 3. On the one hand, the support part 2, represented in Figs. 8, 9 and 10, comprises a support plate 5 designed to remain perpendicular to the strut 10, attachment means 6 and retaining means 7. To couple the strut 10 to the formwork table, it is important to place the support part 2 in the head of the strut 10 so that the small plate 40 which tops the end of the strut 10 remains in contact with the support plate 5 of the support part 2, as the strut 10 receives the loads from the formwork table precisely through the support plate 5. Once the support part 2 is placed on the head of a strut 10, this strut 10 may be suspended from the counter-support part 1 with capacity for oscillation with respect thereto this via the attachment means 6 (see Fig. 6) and subsequently said counter-support part 1 can be retained in a working position, essentially perpendicular to the horizontal structure via the retaining means 7 (see Fig. 7).

On the other hand, the first and second suspension bars 8 and 8' are adapted to receive, in their end portions, respectively the coupling of the attachment means 6 and of the retaining means 7, or vice-versa. In this manner, coupling the attachment means 6 of the support part 2 to one of the suspension bars 8 or 8', the strut 10 may be suspended from the horizontal structure with capacity for oscillation with respect thereto and subsequently, coupling the retaining means 7 to the other suspension bar 8' or 8, the strut 10 can be retained in a working position, essentially perpendicular to the structure. In this way, welding groups of two suspension bars 8 and 8' to the lower part of the longitudinal beams 3, distributed in predetermined positions, the coupling of the struts 10 to a formwork table can be performed quickly and simply.

As has been mentioned, each group of two suspension bars 8 and 8' can be integrated in a counter-support part 1. This counter-support part 1 is indicated to be used in those situations wherein it is necessary to couple a strut 10 in a position other than those predetermined by the welded groups of suspension bars 8 and 8' which will have a least two of the pairs of adjacent longitudinal beams 3 of the formwork table.

The counter-support part 1 further comprises the two suspension bars 8 and 8', a spacing body 9 designed to be housed between two adjacent longitudinal beams 3, suspension means and tightening means whereby the spacing body 9 is stably suspended from the topside of these longitudinal beams 3, the suspension bars 8 and 8' being positioned between the two adjacent longitudinal beams 3, i.e. between the two C-profiles in Fig. 4.

Fig. 1 shows an embodiment of the counter-support part 1. The spacing body 9 represented is elongated in shape and has at each of its ends divergent prolongations traversed by the suspension bars 8 and 8' respectively. The suspension and tightening means of the spacing body 9 represented comprise two vertical screw rods 12 disposed in alignment on the longitudinal axis of the spacing body 9 and respective set nuts 13 and washers 11. As is observed in Fig. 2, to fix the counter-support part 1 of Fig. 1 to the horizontal structure of longitudinal beams 3 and cross beams 4, the spacing body 9 should be positioned in the separation space between two adjacent longitudinal beams 3, represented as C-shaped section profiles, so that the upper ends of the two vertical screw rods 12 protrude from the topsides of said longitudinal beams 3. Then, the washers 11 and the set nuts 13 are inserted through the upper ends of said vertical screw rods 12. Although at the time when the washers 11, positioned under the inserted nuts 13, make contract with the topside of the longitudinal beams 3 the counter-support part 1 is already suspended from these beams, it is necessary for the counter-support part 1 to be stably fixed thereto for greater safety in the working of the system for the coupling of the strut to the formwork table. To do this it is sufficient to continue screwing the set nuts 13 until the suspension bars 8 and 8' come up on their lower part against said longitudinal beams 3. In this way, the only part of the counter-support part 1 of Fig. 1 that is below the longitudinal beams 3 is that formed by the two suspension bars 8 and 8', as is shown in Fig. 5.

According to another embodiment of the counter-support part 1 , not represented in the drawings, the suspension and tightening means of the spacing body 9 comprise at least one hand-rail with a window arranged on the longitudinal axis of the spacing body 9 and the corresponding wedge for the upper fixing of the counter-support part 1 to the adjacent longitudinal beams 3, instead of using the vertical screw rods 12 with the washers 11 and the set nuts 13. In this way, when the wedge is inserted in the window of the hand-rail and tightened, the suspension bars 8 and 8' will act as lower limit against the longitudinal beams 3.

Figs. 6 and 7 show the steps for the coupling of a strut 10 to a formwork table with longitudinal beams 3 starting from the situation represented in Fig. 5, wherein the counter-support part of Fig. 1 is fixedly suspended from two adjacent longitudinal beams 3.

As previously mentioned, the first step for the coupling of a strut 10 to which head the support part 2 has been coupled, consists of suspending the attachment means 6, consisting of two hooks, from the ends of one of the suspension bars 8 or 8'. In this situation, represented in Fig. 6, the strut 10 oscillates with respect to the counter-support part 2. To achieve that the strut 10 is retained in the working position (see Fig. 7), perpendicular to the horizontal surface of the formwork table, it is sufficient to make the strut 10 oscillate in the rotation direction which permits that the retaining means 7 of the support part 2 reaches and grips the other suspension bar, in this case suspension bar 8'.

It is worthy of mention that, as can be observed in Figs. 3 to 7, the support plate 5 of the support part 2 contacts on its upper part with the two undersides of the two adjacent metal longitudinal beams 3, not being necessary in this case that the spacing body 9 is provided with a support surface for the support plate 5, since it is the lower flanges of the two longitudinal beams 3 of the formwork table which directly rest on support plate 5, as the suspension bars 8 and 8' remain just below said beams, thus transmitting the upper loads to the strut 10. Figs. 8, 9 and 10 represent a particular embodiment of the support part

2 of the system for the coupling to a formwork table of a strut 10. It is important to indicate that the support plate 5 of the support part 2 represented is provided with two margins 55 which extend parallel to the direction of the longitudinal beams 3 when the support part 2 is coupled to the horizontal structure of the formwork table and that said margins 55 are positioned at a level above that of the remainder of the support plate 5. It is typical that the metal longitudinal beams 3 are supplied with the lower flanges slightly inclined, so that when they are grouped two by two to form a formwork table, the outer ends of the lower flanges of each group of two beams remain positioned slightly higher that their lower ends. By providing the support plate 5 with the two margins 55, this contact and support zone of the longitudinal beams 3 directly on the support plate 5 can be ensured when the strut 10 adopts the working position. Likewise, Figs. 1 and 2 show that the suspension bars 8 and 8' are configured so that the end portions of each one are also positioned at a higher level than that of the central portion, precisely to ensure the contact of these end portions with the lower flanges of the two longitudinal beams 3. This configuration of the suspension bars 8 and 8' is also applicable in the case that the bars are welded to the undersides of the adjacent longitudinal beams 3, instead of forming part of the counter-support part 1. Fig. 8 shows that the support part 2 comprises two T-shaped side plates

21, separated from one another by the support plate 5. The attachment means 6 consist of two hooks, each one fixed to one of the ends of the upper flanges of the inner sides 22 of the opposing side plates 21. For their part, the retaining means 7 are formed by two clasp hooks each provided with prolongations 27 pivotably joined to the other ends of the upper flanges of the inner sides 22 of the opposing side plates 21.

Fig. 9 shows that the prolongations 27 of the clasp hooks are traversed by a turn stud 23 around which said clasp hooks pivot. The ends of this turn stud 23 traverse the side plates 22 and are fixedly joined to the arms of an actuating handle 24. It is also observed that the ends of these arms are laterally joined to the clasp hooks. Thus, whilst the strut 10 is retained in the working position, situation represented in Fig. 7, the weight of the actuating handle 24 keeps the retaining means 7 suspended from the second suspension bar 8'. To release the strut 10 from the working position, either because the formwork has to be dismounted or it is necessary to reposition the counter-support part 1 , it is necessary to press the actuating handle 24 upwards so that the clasp hooks pivot until they lose contact and they come loose from the second suspension bar 8'. To decouple the strut 10 from the formwork table it is sufficient to release the hooks of the attachment means 6 from the support part 2 from the first suspension bar 8.

It should also be added that to adjust and fix the head of the strut 10 to the support part 2, the latter comprises an adjustment plate 25, essentially perpendicular to the support plate 5, and an adjustment structure 26. When the head of the strut 10 is inserted so that the small plate 40 which tops its end makes contact with the support plate 5, the head is laterally surrounded by the two side plates 21, by the adjustment plate 25 and by the adjustment structure 26.

The adjustment structure 26 comprises two studs 28 parallel to one another which traverse, one for each side of the strut, the adjustment plate 25 situated in the opposite side to the adjustment structure 26. As can be observed in Fig. 9, nuts 29 are screwed in the threaded ends of these studs 28 to achieve that the head of the strut 10 is confined and fitted between the adjustment plate 25 and the adjustment structure 26.

On occasions, when the attachment means 6 of the support part are suspended from one of the suspension bars, for example, from the first suspension bar 8, the case may arise that an operator makes the strut 10 oscillate strongly so that it is that impulse of the oscillation which causes the retaining means 7 of the support part to suspend from the second suspension bar 8' to achieve that the strut 10 adopts the working position.

If this is performed, at the moment when the retaining means are suspended from the second suspension bar 8', a considerable impact will be produced between the strut 10 and the support part 2 which may cause damage or misalignment therein. To avoid these problems, an intermediate part 60 is disposed between the adjustment plate 25 of the support part 2 and the strut 10, configured for its adaptation to the perimeter of the upper portion of the strut 10, as is observed in Figs. 11 and 12. This intermediate part 60 is manufactured in a material compressible in the event of impacts, capable of absorbing said impacts and thus avoiding the support part 2 from suffering damage for this reason. Said intermediate part 60 may be made of a flexible material, such as, for example, polyurethane. Other suitable materials that can absorb the impacts produced may be, for example, rubber, cork or polypropylene, or any bituminous material. Elastic materials will also be valid although with the drawback that as they do not regain their original form after the deformation produced during the impact, the parts 60 should be changed with greater frequency. In addition to the property of absorbing the impact, the intermediate part

60 improves the seal between the adjustment plate 25 and the strut 10, which better fit together, and it also avoids the nuts 29 or lugged nuts from loosening, thanks to the spring effect created by said intermediate part 60.

In short, in most cases, wherein there are no geometric constraints or special load requirements, the struts 10 for the support of a formwork table will be regularly distributed, always being coupled in previously known predetermined positions. For these cases, groups of two suspension bars 8 and 8' will be welded to the undersides of the metal longitudinal beams 3 in these predetermined positions, bars wherefrom the attachment means 6 and the retaining means 7 can be suspended from the support part 2 coupled to the head of each strut 10.

In this way, the counter-support part 1 of Fig. 1 may be used in those circumstances wherein it is necessary to position additional struts 10 in other positions than those predetermined as reinforcement to support the formwork table, as said counter-support part 1 can be removably fixed to the metal longitudinal beams 3.

In conclusion, the system described in this section facilitates the coupling and decoupling jobs of struts 10 to a formwork table, making use of the space between two longitudinal beams 3 to house the spacing body 9 of the counter-support part 1 , as the suspension bars 8 and 8' remain positioned immediately below them, the longitudinal beams 3 resting directly on the support plate 5 of the support part 2. Another advantage of this system lies in the ease of stacking the formwork tables even when several counter-support parts 1 have been fixed thereto such as those of Fig. 1, since the suspension bars 8 and 8' are the only elements which protrude from the bottom of the formwork table.

Claims

C L A I M S

1. System for the coupling of a support strut (10) to the horizontal structure of a formwork table, of the type constituted by longitudinal beams (3) and cross beams (4), the system comprising a support part (2) which can be fixed to the upper end of the strut of the type provided with a support plate (5) perpendicular to the strut, attachment means (6) and retaining means (7) whereby the associated strut can be suspended from the horizontal structure with capacity for oscillation with respect thereto and of being retained in a working position essentially perpendicular thereto respectively, characterized in that said horizontal structure comprises at least one pair of adjacent longitudinal beams provided with at least one group of two suspension bars (8, 8') which extend perpendicular to the direction of the longitudinal beams so that the first and second suspension bars are adapted to receive, in their end portions, respectively the coupling of the attachment means and the retaining means, or vice-versa, of the support part, and in that when the strut is retained in working position, the support plate of the support part receives the direct support of said pair of adjacent longitudinal beams.

2. System according to claim 1 , characterized in that the support plate (5) of the support part (2) is provided with two margins (55) which extend parallel to the direction of the longitudinal beams (3) and which are positioned at a level above that of the remainder of the support plate.

3. System according to claim 1 or 2, characterized in that the two suspension bars (8, 8') are solidly fixed to the undersides of two adjacent longitudinal beams (3), these suspension bars being positioned immediately below said longitudinal beams.

4. System according to claim 1 or 2, characterized in that the two suspension bars (8, 8') are integrated in a counter-support part (1), removably fixed to two adjacent longitudinal beams (3) of the formwork table, which comprises a spacing body (9) designed to be housed between these longitudinal beams (3) said spacing body being provided with suspension and tightening means, whereby said spacing body is stably suspended from the topside of said longitudinal beams, said suspension bars being positioned immediately below them.

5. System according to claim 4, characterized in that the suspension and tightening means comprise at least one vertical screw rod (12) disposed on the longitudinal axis of the spacing body (9) and the corresponding set nut (13) and washer (11) for the upper fixing of the counter-support part (1) to the longitudinal beams (3), the suspension bars (8, 8') acting as lower limit against said beams.

6. System according to claim 4, characterized in that the suspension and tightening means comprise at least one hand-rail with a window disposed on the longitudinal axis of the spacing body (9) and the corresponding wedge for the upper fixing of the counter-support part (1) to the longitudinal beams (3), the suspension bars (8, 8') acting as lower limit against said beams.

7. System according to one of the previous claims, characterized in that the support part (2) comprises two side plates (21), separated from one another by the support plate (5) whereto they are perpendicularly joined, and in that the attachment means (6) of the support part (2) comprise at least two hooks each one fixed to one of the upper ends of the inner sides (22) of the opposing side plates (21).

8. System according to claim 7, characterized in that the retaining means (7) of the support part (2) comprise at least two clasp hooks each provided with prolongations (27) pivotably joined to the other upper ends of the inner sides (22) of the opposing side plates (21).

9. System according to claim 8, characterized in that the support part (2) laterally comprises an adjustment plate (25) and an adjustment structure (26) provided with at least two studs (28), between which the upper end of the strut (10) is confined and fitted when said studs traverse the adjustment plate and corresponding nuts (29) are screwed in its ends.

10. System according to claim 9, characterized in that between the adjustment plate (25) of the support part (2) and the strut (10) is disposed an intermediate part (60) of material compressible in the event of impacts, capable of absorbing the impacts generated between the strut and the support part.

11. System according to claim 10, characterized in that the intermediate part (60) is made of a flexible material.