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Europisches Patentamt

European Patent Office

Office europen des brevets

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(11) EP 1 672 143 A2

(12) EUROPEAN PATENT APPLICATION

(43) Date of publication: 21.06.2006 Bulletin 2006/25

(21) Application number: 05425753.0

(22) Date of filing: 24.10.2005

(51) Int Cl.:E04G 13/02 (2006.01) E04G 9/05 (2006.01)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TRDesignated Extension States: AL BA HR MK YU

(30) Priority: 17.12.2004 IT PD20040316

(71) Applicant: GEOPLAST S.p.A.35010 Grantorto (PD) (IT)

(72) Inventor: Pegoraro, Mircoc/o Geoplast S.p.a.35010 Grantorto (Padova) (IT)

(74) Representative: Vinci, MarcelloUfficio Veneto Brevetti Via Sorio 11635141 Padova (IT)

(54) Reusable modular monobloc formwork for making square or rectangular columns

(57) The invention is a new reusable modular form-work for casting rectangular columns, consisting of aplastic panel (M) with various stiffening ribs on the outside(Me), the sides of which are at a 45 angle to enable theirjuxtaposition up against similar modular formworks of thesame height but different widths. There are holes (Mf) in

the ribbing around the perimeter of the element for theinsertion of means (C) for connecting and locking adja-cent formworks. Four modular formworks can be juxta-posed to create a rectangular self-supporting formworkassembley; several formworks can be stacked andlocked together to obtain a completed self-supporting as-sembly of the required height.

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Description

[0001] This patent relates to the equipment used inconstruction work and particularly concerns a new typeof formwork for making square or rectangular concretepillars or columns.[0002] Previously-prepared formwork made of sheetmetal or wood is generally used to make columns with asquare or rectangular cross-section.[0003] Sheet metal formwork is thick and consequentlyvery heavy, however, so its installation often demandsthe use of a crane or lifting apparatus, or several workers.It needs to be routinely protected against rust and itsweight makes it a constant hazard to workers, especiallywhen it has deteriorated and risks causing injuries ag-gravated by the presence of rust. Its weight also makesit unsuitable for large-scale applications and its usefulsurface area is consequently very limited.[0004] Wooden types of formwork are also known,consisting of flat planks that are assembled together withthe aid of nails, brackets, crossbars and other metalequipment, which may be disposable all reusable.[0005] This patent concerns new reusable plasticmonobloc modular formworks with related keys that canbe joined together to make a self-supporting formworkassembly for casting square or rectangular columns.[0006] The object of the invention is to produce newreusable monobloc modular formworks and correspond-ing keys to make square or rectangular self supportingformwork assembley that is easy to assemble and dis-mantle.[0007] Another object of the new reusable monoblocmodular formwork is to make lightweight and stable formswithout the need for any further external supporting struc-tures.[0008] Another object of the new reusable monoblocmodular formwork is to enable a rapid stripping.[0009] Another object is to prepare formwork suitablefor use in casting various sizes of pillar, be they squareor rectangular, or with other cross sections.[0010] These and other direct and accessory objectsare achieved by the new reusable monobloc modularformwork, which can be attached together with the keysto prepare square or rectangular columns, consisting oflinear elements with flat walls and lateral coupling sur-faces lying at a 45 angle thereto.[0011] The monobloc modular formwork is made ofplastic; it comprises a smooth formwork wall on the insideand has several stiffening ribs on the outside, preferablyequidistant, lying both around the perimeter and over thesurface of the wall.[0012] This ribbing preferably extends at right anglesfrom the plane of the wall and the coupling surfaces.[0013] Holes are provided in the upper and lower pe-rimeter ribbing and in the coupling surfaces to enable theinsertion and rotation of the keys.[0014] These keys consist of a cylindrical body with ahandle at one end (preferably placed at right angles to

said body), and two or more radial projections at the otherend (preferably located at regular intervals).[0015] Four modular formworks are juxtaposed to forma square or rectangular portion of formwork and attachedtogether by means of the keys inserted and rotated inthe aligned holes on said coupled modular form works.Several such formworks can be stacked to obtain a self-supporting formwork assembly of the required height andconnected to one another by means of further identicalkeys. Alternatively, four formworks can be stacked ver-tically and then connected together, after coupling themtwo at a time, around the pillars metal reinforcementbars.[0016] Such compositions ensure the vertical stabilityof the self-supportin formwork prior to casting.[0017] Suitable sloping surfaces are provided on theribbing on the modular formwork in line with the holesand/or on the radial projections on the keys to preventany unwanted rotation of the keys and consequent sep-aration of the various modular elements, thus enablingthe formworks to be locked to one another.[0018] The characteristics of the new reusable mono-bloc modular formwork and related keys for making self-supporting formwork assembly for casting square or rec-tangular columns will be better explained in the followingdescription, with reference to the drawings, which areattached as a nonrestrictive example.[0019] Figures 1 and 2 respectively illustrate two or-thogonal views of a modular formwork (M) for use in com-bination with other similar modular formworks (M), forcasting square or rectangular columns.[0020] The modular formwork (M) consists of a plasticpanel of generically flat cross-section with coupling sur-faces (Me) sloping at a 45 angle to the plane (M1) ofsaid panel, suitable for juxtaposing with similar modularformworks (M), as shown in figure 4a.[0021] Said formork (M) is complete with several stiff-ening ribs (Mn) on the outside (M2) and further stiffeningribs (Mo) lying around its perimeter.[0022] The ribs (Mn) on the outside are distributed overthe whole of said outer surface (M2) of the modular form-work (M).[0023] The ribs on the upper and lower perimeter (Mo)of the panel forming the modular formwork (M) are pref-erably thicker and wider.[0024] The upper and lower perimeter ribbing (Mo) al-so provides a surface for supporting or connecting furthermodular formworks (M) above and below each element(M).[0025] Holes (Mf) are provided in said perimeter rib-bing (Mo) and in said coupling surfaces (Me), that arepreferably circular in shape and have two or more dia-metrically opposite grooves (Mf1).[0026] Said holes (Mf) are arranged at regular intervalsalong the perimeter ribbing (Mo) and the coupling sur-faces (Me) and in such a manner that, when several mod-ular formworks (M) are coupled together or stacked, saidholes (Mf) in one formwork (M) are exactly aligned with

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the corresponding holes (Mf) in the adjacent formwork(M).[0027] The distance between the outermost holes (Mf)in each elements perimeter ribbing (Mo) or coupling sur-face (Me) and the end of the ribbing (Mo) or couplingsurface (Me) is narrower than, and preferably half thedistance between the other holes (Mf) lying along saidribbing (Mo) or coupling surface (Me) on the modularformwork (M).[0028] The surface on the inside (M1) of the new mod-ular formwork (M) is smooth and preferably treated soas to prevent the concrete from adhering thereto.[0029] Figures 3a, 3b and 3c show three non-restric-tive and non-exhaustive examples of modular formworks(M) in different sizes.[0030] Modular formworks (M) of different sizes canbe coupled in different combinations to obtain formworkof the required dimensions for casting square or rectan-gular columns.[0031] The various modular formworks (M) can be con-nected with straps or, preferably, with specific keys (C).[0032] Figures 5 and 6 respectively illustrate a sideview and an axonometric view of such a key (C).[0033] The key (C) consists of a body (C1) with a han-dle (C2) at one end and two or more radial projections(C3) at the other end.[0034] The body (C1) of the key (C) is generically cy-lindrical in shape and has the same diameter as that ofthe holes (Mf) in the perimeter ribbing (Mo) and couplingsurfaces (Me) on the modular formwork (M); its lengthexceeds the thickness of two perimeter ribs (Mo) or cou-pling surfaces (Me). To be more precise, said body (C1)has a portion (C11) of the end near the handle (C2) thatis larger in diameter than the rest of the body (C1).[0035] The handle (C2) at one end of the body (C1) isa portion lying at right angles to the body (C1) and maybe shaped (C21) so as to provide a better grip.[0036] The two or more radial projections (C3) at theopposite end of the body (C1) are diametrically oppositeone another and preferably in the form of a segment ofa ring.[0037] Said radial projections (C3) are of such lengthand width that they can pass through the grooves (Mf1)in the holes (Mf) in the perimeter ribbing (Mo) and cou-pling surfaces (Me) on the modular formwork (M) whenthe key (C) is inserted in said holes (Mf).[0038] A stable connection of the various modularformworks (M) is achieved by inserting said key (C) inthe holes (Mf) in the perimeter ribbing (Mo) and couplingsurfaces (Me) of the juxtaposed modular elements (M)so that the radial projections (C3) on said keys (C) bothextend beyond the holes (Mf), and then rotating said keys(C) so that said radial projections (C3) are no longeraligned with the grooves (Mf1) in said holes (Mf).[0039] Figure 7 shows an example of two modularformworks (M) connected by means of said key (C).[0040] Provision can be made for said radial projec-tions (C3) and/or the plane of the perimeter ribbing (Mo)

or coupling surface (Me) in line with the holes (Mf) to lieat an angle so as to induce a compressive force betweenthe two perimeter ribs (Mo) and between the two couplingsurfaces (Me) of the juxtaposed modular formworks (M)when the key (C) is rotated.[0041] The keys (C) thus described are equally suita-ble for the connection of four modular formworks (M) jux-taposed so as to form a tube, or the connection of modularformworks (M) stacked so that one acts as an extensionof the other, simply by inserting and rotating each key(C) in the aligned holes (Mf) of the juxtaposed formworks(M).[0042] Figures 4a, 4b and 4c show three non-restric-tive and non-exhaustive examples of combinations ofvarious modular formworks (M, M, M") of different sizesallowing rectangular columns in different sizes to be ob-tained.[0043] The reusable monobloc modular formworks (M)and corresponding keys (C), made as described aboveto enable the construction of self-supporting formworkassemblies for casting square or rectangular columns,offers considerable advantages.[0044] These modular formworks (M) are lightweight,shock-resistant, easy to transport and easy to assemblesimply by inserting and rotating the keys (C) on the pe-rimeter ribbing (Mo) and coupling surfaces (Me) of jux-taposed elements.[0045] The modular formworks (M) enable a rapidstripping of the self-supporting formwork assembly soonafter casting the concrete, simply by rotating and remov-ing the keys (C) that hold the modular formworks (M)together.[0046] The self-supporting formwork assembly pre-pared with the above-described modular formworks (M)and keys (C) need no specific external structures to main-tain the alignment of the self-supporting formwork as-sembly as a whole because, thanks to the use of the keys(C), said formworks are connected together to producea tubular structure that remains very stable during thecasting operations.[0047] Juxtaposing modular formworks (M, M, M") ofthe same height but different width enables the quick andeasy preparation of rectangular self-supporting formworkassembly of the required dimensions.[0048] Thus, with reference to the preceding descrip-tion and to the attached drawings, the following claimsare advanced.

Claims

1. Reusable monobloc modular formwork for makingpillars or columns, characterized in that it consistsof a generically flat plastic linear element (M) with asmooth surface (M1) forming the inside wall of theform, while on the outside (M2) there are stiffeningribs along its upper and lower perimeter (Mo) andintermediate stiffening ribs on the surface of the wall

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(Mn), wherein the sides of said wall include couplingsurfaces (Me) sloping at a 45 angle to said wall (M1),so as to enable their orthogonal juxtaposition withother identical modular formworks (M) to form asquare or rectangular a self-supporting formwork as-sembly.

2. Reusable monobloc modular formwork, accordingto claim 1, characterized in that the intermediateribbing (Mn) on the outside (M2) lies at right anglesand/or parallel to the coupling surfaces (Me).

3. Reusable monobloc modular formwork, accordingto the previous claims, characterized in that theperimeter ribbing (Mo) along the upper and loweredges of the modular formwork (M) are of sufficientthickness and width to enable their coupling with theupper and lower perimeter ribbing (Mo) of an identi-cal modular formwork (M) juxtaposed thereto.

4. Reusable monobloc modular formwork, accordingto the previous claims, characterized in that thelinear element (M) is designed to be juxtaposed withsimilar linear elements (M, M") of the same heightbut different width.

5. Reusable monobloc modular formwork, accordingto the previous claims, characterized in that thecoupling surfaces (Me) on the sides of the modularformwork (M) are of such thickness and width as toenable their coupling to the corresponding couplingsurfaces (Me) of an identical modular formwork (M)juxtaposed thereto.

6. Reusable monobloc modular formwork, accordingto claim 1, characterized in that it has holes (Mf)in the upper and lower perimeter ribbing (Mo) andlateral coupling surfaces (Me), said holes being pref-erably circular in shape with two or more grooves(Mf1) lying diametrically opposite one another,wherein said holes (Mf) are arranged along the upperand lower perimeter ribbing (Mo) and in the lateralcoupling surfaces (Me) so that, when several mod-ular elements (M) are juxtaposed or stacked, saidholes (Mf) in the various juxtaposed or stacked mod-ular elements (M) are aligned with one another.

7. Key (C) for use with modular formworks (M), char-acterized in that it consists of a cylindrical body (C1)with a handle (C2) perpendicular to said body (C1)at one end and two or more radial projections (C3)at the other, wherein said cylindrical body (C1) hasthe same diameter as the diameter of the holes (Mf)in the perimeter ribbing (Mo) and coupling surfaces(Me) of the modular formwork (M) and has a lengththat is greater than the thickness of two perimeterribs (Mo) or two coupling surfaces (Me), and whereinsaid radial projections (C3) are preferably in the form

of a segment of a ring so that they can pass throughthe grooves (Mf1) in the holes (Mf).

8. Key according to the previous claim, characterizedin that it has said radial projections (C3) lying at anangle.

9. Reusable monobloc modular formwork, accordingto any of the previous claims from 1 to 6, character-ized in that it is connected to other similar formworksby means of keys as described in claims 7 or 8,wherein said connection assures the stability of theself-supporting formwork assembley.

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