Formwork table
A formwork table (10) has a formwork skin (12) attached to a plurality of transverse beams (14) and at least two truss beams (16) made of steel, to which the transverse beams (14) are attached and which are provided along substantially their entire length at regular spacings with bore holes (18), by means of which connecting heads (20), which provide the connection to props (22), are respectively attached to a single truss beam (16) and may be attached along substantially the entire length of the truss beam (16).
The invention relates to a prefabricated formwork table, as used for construction work and in particular for the forming of ceilings.
When an intermediate floor of a concrete building is to be concreted, a substantially horizontally arranged formwork skin is created, whose edges are delimited by end shuttering. The formwork skin may be formed by a plurality of formwork panels laid on transverse beams, which in turn are laid perpendicular thereto on truss beams. The truss beams are usually supported on the floor at a plurality of points by ceiling props.
PRIOR ARTFrom EP 0 945 564 A1, a ceiling formwork table is known that is prefabricated to the extent that the formwork skin is attached in the form of a plurality of formwork panels to the transverse beams and these are attached to the truss beams. Linking elements which can interact with linking elements provided on the upper side of the ceiling props are also provided on the truss beams. By means of the prefabricated unit which comprises formwork panels, the transverse and truss beams, modular elements may be provided which still have only to be provided with the props in order, together with further such elements, to form a complete ceiling formwork. The prefabricated elements may be transferred. in a time and cost-saving manner between individual storeys for concreting the floors of a multistorey building one after the other.
DE 100 56 831 C1 discloses a similar ceiling formwork device, whereby at least the truss beams are made of steel. The props are attached to load-bearing frames, each of which is fixed between two adjoining truss beams.
DESCRIPTION OF THE INVENTIONIt is the object of the invention to provide a ceiling formwork table which is improved in an efficient manner with regard to its usage possibilities.
The solution of this object is achieved by means of the formwork table disclosed in claim 1.
As a consequence, the prefabricated formwork table according to the invention has a formwork skin that is attached to a plurality of transverse beams. The formwork skin may, for instance, comprise a plurality of formwork panels. It is preferred that the transverse beams are made of wood. By contrast, at least two truss beams made of steel are provided to which the transverse beams are attached. The necessary props may be attached to the truss beams in that connecting heads which serve for attaching the props may be attached, respectively, to a single truss beam. This is thereby realised in that at least two of the truss beams present are provided at regular intervals along their entire length with bore holes. The aforementioned connecting heads are attached to these bore holes. This may be undertaken, for instance, by bolts extending through them and fastened. With regard to the attachment of the props to the connecting heads, it should be mentioned that this may take place by means of a wedged joint. This means that one or more wedges are hammered in such that they firmly clamp a prop, by means of a head plate provided at their upper end, to the connecting head. With regard to the connecting head, it should also be mentioned that this may also be designated simply “head”, “head connection” or similar. Essentially, any element is suitable to which a ceiling prop is connectable and which itself is connectable to a single truss beam by means of the bore holes provided therein.
The possibility according to the invention of attaching each of the connecting heads to a single truss beam, leads to the advantage compared with DE 100 56 831 C1 that the load-bearing frames disclosed therein that are to be attached between two truss beams are dispensable. According to the invention, the connecting heads can be designed relatively simply and economically in that they are attached directly to a single truss beam. In order to improve the interaction with markings which can be provided on the truss beams, a marking may be provided on each connecting head so that when the two markings are brought into alignment with each other, the bore holes of the beam, on the one hand, and of the connecting head, on the other hand, are aligned with each other.
The provision of bore holes at regular spacings substantially along the entire length of the truss beams leads, on the one hand, to the advantage that the connecting heads may be fixed almost steplessly along the entire length of a truss beam. By this means, props may be attached to one and the same formwork table in a flexible manner, as is required for adaptation to different ceiling thicknesses and therefore different concrete weights. In other words, the spacings between the props may be arranged on identically designed formwork tables, such that adequate conduction of the forces via the props is assured. Furthermore, fitting of the heads to the truss beams may be carried out relatively quickly, since, for instance, bolts need only to be inserted through bore holes in the connecting head, on the one hand, and the truss beam, on the other hand, and then secured. This results in a significant time saving compared with fixing by means of metric screws inserted into threads in the truss beam.
The consistent formation of bore holes in the truss beams also offers the advantage that numerous add-on parts may be affixed to the truss beams without difficulty. For instance, by means of the bore holes, a prop connection may be affixed such that a prop may be attached in tilted orientation in order to secure a formwork table in the horizontal direction against the floor in both compression-proof and tension-proof manner and/or to undertake adjusting procedures. Furthermore, by means of the bore holes, connections of the most varied of elements using connecting straps are possible without difficulty. With connecting straps, for instance, two adjacent formwork tables may be connected to one another. Furthermore, with one or more connecting straps, a compensating formwork element or a working platform may be attached as a table platform. A table platform of this type may, however, also be attached directly to the truss beams in that the bore holes provided in the truss beam are also used for such a purpose. A connecting strap may also be designed as an angled strap and serve in this manner for fixing a truss beam for girders. This involves formwork sections situated on a lower level than the level of the actual ceiling formwork. It should also be mentioned that for the bore holes in the truss beams of the formwork table according to the invention, it is preferable that they are provided with a spacing corresponding to the spacing of commonly used steel bay rails. This essentially involves the beams of wall formwork elements made of steel. In that the usual spacing between bore holes is used in a novel manner, numerous add-on parts that have proved useful in the field of wall formwork may be used for the formwork table according to the invention. Thus the usability of a formwork table together with other formwork components is extended overall, and a higher degree of flexibility on use of a formwork table is achieved in an efficient manner. It should also be mentioned that in place of individual props, one or more frame elements may also be provided on the formwork table, said elements assuming the function of a plurality of props and/or being interposed between the formwork table and individual props.
Preferred further developments of the invention are disclosed in the other claims.
For the truss beams, it is preferred that these have at least one U-profile. The “base” of the U is usually substantially perpendicular to the formwork skin, so that the bore holes are formed in this “base”. The limbs of the U may advantageously be used for connecting two U-profiles to each other and/or for connecting the truss beams to the transverse beams and supporting them on the truss beams. Furthermore, that limb of the U-profile which faces away from the formwork skin in particular may be used for the clamping of anchorings. In this context, a concept from the field of wall formwork is utilised in that a plate-like clamping element of an anchoring is provided such that it is supported on said limb.
Alternatively or in addition hereto, the truss beam may have at least one formed tube. In this embodiment, also, an advantageous design of the truss beam may be realised.
For the bore hole spacings, as mentioned above, it is preferable that these correspond to the bore hole spacings provided in steel bay rails. This produces the described advantageous compatibility of the novel formwork table with numerous components from the field of wall formwork.
It is further preferred within the scope of the invention that visually perceptible markings are assigned to individual bore holes. For instance, those bore holes may be marked in a particular manner which are for use in “standard situations” for mounting the connecting heads. Standard situations should be understood to mean that the formwork skin is to be supported in more or less standard manner for ceilings up to a particular thickness. Only with thicker ceilings must further and/or other bore holes be used in order to provide the connecting heads at a smaller spacing, as is then required for the larger number of props necessary compared with standard cases. The bore holes to be used in this case may also be marked in suitable manner. Using different colours, different groups of bore holes which need to be selected in particular cases, i.e. up to a respective maximum permissible load, can be distinguished from each other. In this regard, it is naturally equally conceivable that only those bore holes which are required for particular cases are provided. However, flexibility during use increases when additional bore holes are provided, whereby as described, it is preferable that the bore holes for use in particular cases are marked. Finally, a bore hole in the centre of the truss beam could be marked in a particular manner in order to indicate to operatives that this is the centre and that transfer devices with a limited support width for the truss beams, with which the formwork table is lifted for transfer, are to be placed at this centre in order to prevent tilting of the formwork table. In this regard, it should be mentioned that in addition to, or alternatively to, the markings mentioned above, markings may also be provided which are not necessarily assigned to individual bore holes. These markings may, for instance, serve as position markings to show which points on the formwork table are placeable on formwork tables lying underneath them, or where on the formwork table further formwork tables may be laid.
In order to adopt the fundamental connecting and anchoring possibilities from the field of wall formwork to the greatest possible extent, it is also preferable for the truss beams that they comprise two profiles spaced apart by 15 cm or less, preferably 10 cm or less and particularly approximately 5 cm. The two profiles may be U-profiles whose “bases” are directed towards each other. These bases may also be designated webs and the limbs of the U which extend from the base could be designated flanges. Thus each truss beam comprises two such profiles and is, in effect, constructed like the steel bay rails of wall formwork elements. By this means, the proven connecting and anchoring possibilities may be realised in advantageous manner on a beam constructed in this manner. The arrangement of the two profiles of a beam constructed by this means, relatively close to each other, offers the advantage that the necessary forces may be borne without intermediate elements and load-bearing frames as has previously been necessary. In this regard, it should be noted in particular that in a condition of a formwork table raised above the ground, at the free ends of the several metre-long props, significant moments can be transferred by the props to the beams, which are absorbed in advantageous manner by the limbs of the U-profile facing away from the formwork skin.
For the described construction of a truss beam from two profiles, it is preferable that they are connected to each other by means of straps to which the transverse beams are also attached. These straps may have stiffening ribs and may, for instance, be welded to the two profiles of the truss beam. The linking of the transverse beams may take place via bore holes, which are formed, on the one hand, in the straps and, on the other hand, in the transverse beams.
Preferably, the connecting heads are detachably affixed to the formwork table. By this means, a particularly space-saving stacking is achieved for transportation and storage of the formwork table by removing the connecting heads from the table. The connecting heads are detachable and remountable particularly rapidly and simply, since for this only the pushing—or hammering—in of, for instance, two bolts per connecting head is required. By this means, following space-saving stacking for transport and storage, rapid completion of the formwork table according to the invention is possible at the site of use. The space-saving stacking for transport leads, for instance, to the advantage that less transport space is required, and thus to a reduction of transport costs.
Although for the formwork table according to the invention, it is essential only that connecting heads which serve to connect with props are attached to it, it is provided within the scope of a preferred embodiment that at least one connecting head is designed to be pivotable. This offers the advantage that the props attached to a formwork table do not have to be removed for space-saving, but may be pivoted such that they are oriented inclined and/or almost parallel to the formwork skin. In an orientation parallel to the formwork skin, the formwork table according to the invention may be transported and stored in a space-saving manner. Furthermore, in this orientation, moving out of a building, as described in greater detail below is possible, even through extremely small openings in the building. In an at least tilted orientation of the props, the formwork table may be moved from one story to a story situated above it whose ceiling is to be made in that it is moved out of the story already made via a building opening such as a window or breastwork. This procedure may also be performed by use of a pivoting head without removing the props. Particularly due to the fact that the connection between the connecting heads and the truss beams may be designed significantly differently from in the prior art, the invention enables the use of truss beams of relatively small structural height. This is at the current time preferably approximately 12 cm.
For the pivoting head described, it is preferable that it has a locking strap or latch, which is provided with an eccentric curve for fixing the pivoted-out position of the prop. In this context, the pivoted out position is understood to be that position in which the props extend at an angle of approximately 90° to the formwork skin. The latch is provided pivotably on the pivoting head and may be brought into engagement by means of the eccentric curve described, which is formed, for instance, on a hook-shaped projection, with a pin or bolt on the counter-member such that by rotating the latch into the locking position, increasing pressing of the counter-member onto the truss beam takes place. A prop may be attached to the counter-member described by means of a wedge mechanism such that the prop is thereby particularly reliably and firmly fixed.
For the latch described, it is also preferable that it has at least one detent possibility in the pivoted-in position of the prop. The pivoted-in position is understood to be a position in which the prop extends inclined or parallel relative to the formwork skin. For instance, a detent may be provided in a 10°-position of the prop (relative to the formwork skin) in order to achieve a significantly diminished alignment of the formwork table in order to be able to transfer it to the story above through, for instance, a window opening in a building. Furthermore, a detent for the alignment of the props parallel to the formwork skin may be provided as a storage and transportation position.
For the latch, further advantages are produced when, in a pivoted-out position of the prop, it curves away from a prop attached to the connecting head. In this embodiment, the latch does not unnecessarily project obliquely downwards from the underside of the formwork table but, due in part to the course of the curvature, lies against the formwork table. This prevents any hindrance of work in the region of the connecting head. Furthermore, by means of this “lying against” the formwork table, the structural depth of the formwork table is particularly small so that a plurality of formwork tables may be stacked in particularly space-saving manner.
Further advantages may be achieved with a design whereby the connecting head has at least one relatively soft support pad on its underside. Since the underside of the connecting head in the condition with the props removed comprises the underside of the formwork table, a favourable stacking capability may be achieved with a support of this type. By means of the soft support pad, the formwork table may be laid on the formwork skin of a formwork table lying beneath without any danger of damage to the formwork skin of the table lying underneath. Relatively soft is understood in this context to mean that the support is made, for instance, of plastics or the like so that damage through the placement of an element made of steel onto the formwork skin, which is usually made of wood, is avoided. With regard to the pivotable connecting head—also pivoting head—described above, it should be pointed out that said head shows advantages independently of the formwork table according to the invention. Therefore a pivoting head for connecting a ceiling prop and a beam, which may be made either of steel or of wood, or of any other suitable material, said head being able to have the features mentioned above and below in any combination, is described as an independent object.
As described, the formwork table according to the invention shows its advantages particularly with regard to its compatibility and combinability with the most varied add-on elements. Within the context of a preferred embodiment, it is therefore provided that the formwork table is provided with at least one connecting strap and/or at least one anchoring element and/or at least one table platform. This reflects several of the different extension possibilities of the formwork table according to the invention and the possibility of combining a plurality of formwork tables arranged adjoining each other. In the direction of the truss beams, this may be provided, as mentioned, through suitable connecting straps. In the direction perpendicular to this, anchoring elements which are inserted through the bore holes provided in the truss beams may be used. Making use of the bore holes in the truss beam, an add-on member, such as an anchoring element, provided in a direction perpendicular to the formwork skin may also be secured against falling.
BRIEF DESCRIPTION OF THE DRAWINGSThe invention will now be described in greater detail by way of example and with reference to the drawings, in which:
As
In the example shown, the connecting straps 26 are provided with two substantially vertically extending strengthening or stiffening ribs. In their lower region, they also have a shoulder, so that they are adapted to the contour of the transverse beams which each have a broadened flange on the upper and lower sides and, between these, a narrower web. The fastening between the connecting straps 26 and the transverse beams 14 is made with screw connections. It should be mentioned finally that in the example shown, the connecting straps 26 in the left-hand region of the table lie on the transverse beams 14 from the right-hand side, and in the right-hand region of the table, contact is from the left-hand side. Finally, it is noteworthy that the separation between the plurality of transverse beams 14 is irregular, in order to take account of the different loading situations existing at different parts of the table. Attachment of the formwork panels comprising the formwork skin 12 otherwise takes place with nails, screws or similar.
As is also clearly apparent from
Attachment of the props takes place substantially with a wedge mechanism. Firstly, the double wedge 54 shown in
The pivoting head shown in
Also shown in
In order to loosen and pivot the holder 46 out of the position shown in
In the upper right region of
Claims
1. A formwork table a formwork skin attached to a plurality of transverse beams, and at least two truss beams made of steel, to which the transverse beams are attached, and which are provided along substantially their entire length at regular spacings with bore holes, by means of which connecting heads, which provide the connection to props, are respectively attached to a single truss beam and may be attached along substantially he entire length of truss beam
2. The formwork table according to claim 1, wherein the truss beams have at least one U-profile.
3. The formwork table according to claim 1, wherein the truss beams have at least one formed tube.
4. The formwork table according to claim 1, wherein the bore hole spacings correspond to the bore hole spacings of steel bay rails.
5. The formwork table according to claim 1, wherein visually perceptible markings the truss beams have at least one formed tube.
6. The formwork table according to claim 1 wherein the truss beams comprise two profiles spaced by 15 cm or less.
7. The formwork table according to claim 6, wherein the two profiles are linked by means of straps (26), to which the transverse beams are also attached.
8. The formwork table according to claim 1, wherein the connecting head is detachably mounted on the formwork table.
9. The formwork table according to claim 1, wherein at least one connecting head is designed pivotably.
10. The formwork table according to claim 9, wherein the connecting heads each have a latch provided for fixing the props, in a pivoted-out position, to an eccentric curve.
11. The formwork table according to claim 9 wherein the connecting heads each have a latch which has at least one detent mechanism (74, 76) for a pivoted-in position of the prop.
12. The formwork table according to claim 10, wherein in a pivoted-out position of the prop, the latch is curved away from a prop attachable to it.
13. The formwork table according to claim 9, wherein the connecting head has at least one relatively soft support pad on its underside.
14. The formwork table according to claim 1, further comprising at least one connecting strap and/or at least one anchoring element and/or at least one table platform.
15. The formwork table according to claim 1, wherein the truss beams comprise two profiles spaced by 10 cm or less.
16. The formwork table according to claim 1, wherein the truss beams comprise two profiles spaced approximately 5 cm from each other.
Type: Application
Filed: Dec 17, 2004
Publication Date: Jul 7, 2005
Inventor: Walter Holawe (Neumarkt/Ybbs)
Application Number: 11/016,262