FOR CONCRETE SHUTTERING SYSTEM

FIELD OF THE INVENTION

The present invention generally relates to Improvements of formwork panel units for forming concrete structures, and more particularly to a modular formwork panel unit, preferably made of plastic, for concrete shuttering system, especially for the construction of concrete walls, floor, ceiling, beams, slabs and/or pillars.

BACKGROUND OF THE INVENTION

In the prior art, the modular formwork panel units of such particular type that need to be significantly improved and modified are disclosed and taught in International Publication No. WO 2009/064157, Such modular formwork panel unit has a planar sheet main body defined by smooth inner and ribbed outer surfaces bounded around or along its perimeter by spacedly apertured adjoining side portions. A co-extending reinforced groove is provided along its side portions, which Is interposed between an outwardly tapered first side edge and a nan-tapered second side edge. A plurality of such panel units Is being securely fastened together in assembly by a connecting means.

When the formwork panel units are jointed to and/or jux!aposediy abutted against each other using the connecting means that tightly clamp/fasten them together along their respective peripheral ribs, thus, closely, if not abuttlngly, bringing their spaced apart non-tapered corner edges together, the abutment of the opposite tapered/convergent comer edges is functionally affected. The forcible clamping/abutment of the spaced-apart, non-tapered corner edges thereof, deflecting them forcibly towards each other and an abutted position, has negative influence/effect on the abutment accuracy and disposition of the opposite tapered/convergent corner edges at the Inner surfaces of the jointed panel units, making the panel joint(s) relatively and/or slightly wider. Consequently, there would result unwanted more recognizable/ visible joint mark(s) on the formed concrete which may not be desirable/acceptable to the building construction industry where accuracy and high quality of formed concrete are normally of important/critical consideration. Specifically, such abutment or bringing together of the spaced-apart, non- tapered comer edges by clamping structurally produces slight bends or bulges on the inner surfaces due to their unbalanced, non-symmetrical displacement and unstable abutment. The resulting in slightly non-flattened or bulging inner surfaces are consequently translated to uneven surfaces of the formed concrete, most especially in cases where the weight of poured wet concrete or mortar fails or is not sufficient enough to push back the bulgingly bent inner surfaces in usage. Further, the deflectability and/or joint instability of the jointed or abutted tapered corner edges as influenced by the non-tapered corner edges decreases the durability factor or life span of the panel units.

SUMMARY OF THE INVENTION

The present invention seeks to overcome the problems and/or shortcomings of the prior art by providing a modular formwork panel unit for a concrete shuttering form system, specifically for the construction of walls, floors, ceilings, beams, slab and/or pillars that generally comprises, as part of old elements/features, planar sheet having smooth inner and ribbed outer surfaces perimetrically bounded by spacedly apertured adjoining side portions having co-extending reinforced groove interposed between an outwardly tapered first side edge and a non-tapered second side edge along the perimeter of the formwork panel unit such that a plurality of the units being securely fastened together in assembly by a connecting means. The modular formwork panel unit is characterized in that the second side edge is also made outwardly tapered such that the reinforced groove is interposed in between the resulting pair of oppositely and outwardly directed side edges whose respective corner edges are abutted face-to-face against same corner edges of juxtaposedly and stably mounted same panel unit in assembly.

Due to the symmetrical position/disposition and/or structural set-up of the opposite abutted tapered corner edges in assembly, their edge-to-edge abutments which are disposed along their common line of contact securely effect and ensure tight fit jointing or abutment of the jointed panel units through their tapered corner edges. Hence, this results in a significantly increased and much improved stability, durability and/or joint(s) accuracy of the corner edges especially on the smooth inner surfaces that are in contact with the poured concrete. With such set-up, there is produced a substantially, if not completely, seamless/grooveless quality formed concrete, and any instability tendencies and/or unwanted movement or displacement of the jointed formwork panel units are significantly minimized, if not totally eliminated.

Overall, with the securely balanced and/or symmetrical abutment of the tapered corner edges of the present jointed panel units, there result accurately and/or perfectly flattened (non-bulging) abutted jointed smooth inner surfaces, and at least substantially, if not perfectly, seamless and/or grooveless panel joint(s) that produces completely flat and even formed concrete surfaces.

It is therefore the primary object of the invention to provide an improved modular formwork panel unit with tapered/convergent second side corner edges that are capable of being abutted symmetrically and in a balanced manner such that there is produced/installed accurately and/or perfectly flattened (non-bulging) abutted jointed smooth inner surfaces, and at least substantially, if not perfectly, seamless and/or grooveless panel joint(s) that produces completely flat and even formed concrete surfaces; and any instability tendencies and/or unwanted movement or displacement of the jointed formwork panel units are significantly minimized, rf not totally eliminated; and there results a structural assembly set-up that is strong enough to withstand the pressure caused by expansion of setting concrete, poured concrete or other forces, and also reduces, if not completely eliminate, deflectability of the jointed corner edges and/or formwork panel units, while at the same time increasing durability factor thereof.

Another object thereof is to provide an improved modular formwork panel unit that is not only simple in design, readily reusable, lightweight, and easily installable, but, more importantly, provides a favorably smooth, even, seamless/grooveless surface finish to the wall when formed concrete is cured, and has no secondary tedious processes, such as surface cleaning and taxing maintenance, are needed to be performed thereon, hence, eliminating the use of release agent for the dismantling of the installed formwork panel units, resulting in reduced operation and maintenance costs.

Still another object thereof is to provide an improved modular formwork panel unit that is so practically beneficial, most especially in concerned and related industries and businesses, while utilizing widely available materials and simple technology, thus very economical to manufacture and most marketable to commercialize.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings constitute a part of this specification and include an exemplary or preferred variations of the invention, which may be embodied in various forms. It is to be understood that in some instances various aspects of the invention may be shown exaggerated or enlarged to facilitate an understanding of the invention. Other objects, features and advantages of the invention are better understood and appreciated from the following detailed description made in conjunction with the appended drawings, in which:

FIG. 1 is a perspective view of a preferred variation of the present invention in form of modular formwork panel units of different and/or same standard modular sizes juxtaposedly jointed or attached together in assembly, showing their smooth inner surfaces;

FIG. 1 A is an enlarged inset view thereof as referred to and indicated in FIG. 1, illustrating the contact portions or abutting tapered side edges and corner edges of the two attached/jointed formwork panel units;

FIG. 1B is a front view thereof as referred to FIG. 1 A;

FIG. 1.1 is a perspective view of another preferred variation of the present invention in form of modular formwork panel units of different and/or same standard modular sizes juxtaposedly jointed or attached together in assembly, showing their smooth inner surfaces;

FIG. 1.1 A is an enlarged inset view thereof as referred to and indicated in FIG. 1.1 , illustrating the space-apart, non-abutting but convergently tapered side second side edges of the two attached/jointed formwork panel units; FIG. 1.1B is a front view thereof as referred to FIG. 1.1A;

FIG. 1C is a fragmentary, enlarged front view of the existing jointed formwork panel units of the prior art presented in the same manner as those of FIGs. 1B and 1.1B comparatively showing its non-abutting space-apart and non-tapered second side edges in assembly;

FIG. 2 is a perspective view thereof as referred to FIGs. 1 and 1.1 , showing the back side or opposite ribbed outer surfaces of the juxtaposedly jointed/attached formwork panel units thereof;

FIG. 2A is a perspective view thereof presented in the same manner as that of FIG. 2, showing juxtaposedly jointed/attached formwork panel units of smaller standard modular sizes;

FIG. 3 is a partially enlarged perspective view thereof as referred to FIGs. 2 and 2A, illustrating reinforced ribs further provided at the ribbed outer surfaces thereof, and connecting means securing the formwork panels’ juxtaposed attachment/assemblage; and

FIG. 4 is a fragmentary enlarged perspective view thereof, showing another type of connecting means for connecting two or more formwork panel units.

DETAILED DESCRIPTION Before describing the invention in detail, it is to be understood that the phraseologies and terminologies employed herein are for purposes of description only to support an enabling disclosure, thus should not be regarded as limiting. Hence, specific structural and functional details disclosed herein are not interpreted as limiting, but merely as the basis for the claims and also as a representative basis for teaching one skilled in the art in employing the preferred variation(s) of present invention in virtually any appropriate detailed structures.

Referring now to the drawings in detail wherein like reference numerals designate the same parts or elements all throughout the description, there is generally shown in FIG. 1 a modular formwork panel unit 10, and a variation thereof 10’ (shown in FIG. 1.1), for a concrete shuttering form system comprising a smooth inner surface 12 (that is in contact with the poured concrete mix or mortar) and an opposite ribbed outer surface 14, both these surfaces perimetrically bounded by spacedly apertured adjoining side portions 13. In assembly or when installed onsite, a plurality of the formwork panels or panel units 10,10’ is securely fastened together in juxtaposed arrangement/position (shown in FIGs. 1, 1.1, 2 and 2A) by connecting means 15. The panel unit(s) 10,10’ can be of any desired or standard sizes such as, preferably, 600 mm x 1,200 mm and 300 mm x 1,200 mm connected together (FIGs. 1, 1.1 and 2), 150 mm x 300 mm and/or 200 mm x 300 mm connected together (FIG. 2A), 250 mm x 1 ,200 mm, 200 mm x 1 ,200 mm, 150 mm x 1 ,200 mm, 100 mm x 1,200 mm, 50 mm x 50 mm, 4ft x 8ft, or any other preferred or suitable sizes.

The side portions 13 define a side frame 20 generally formed by longitudinal edge 20a and lateral edge 20b being provided with respective integral co-extending reinforced groove(s) 22 along the perimeter of the formwork panel unit(s) 10,10’. The reinforced groove 22 is formed on the frame 20 defining an outwardly tapered first side edge 22a and a non-tapered and/or straight second side edge 22b along the perimeter of the formwork panel unit, which forms part of the features of the conventional formwork panel unit 10” shown in FIG. 1C. The first side edge 22a is tapered at a predefined angle along the perimeter of the formwork panel unit 10,10’ and 10”. A plurality of predetermined spaced apart apertures 26, preferably equally formed, is provided on the reinforced groove 22 along the perimeter of the panel unit 10,10’ or 10”. Preferably, each aperture 26 has integrally formed circumferential reinforced loop 26a that strengthens its opening that is of sufficient size to receive the connecting means 15 or construction support accessory.

The improvement introduced into the conventional formwork panel unit 10” and made in combination with the old components or features of the latter is substantially applied on the second side edge 22b as can be clearly seen in FIGs. 1A and 1B. With such improvement, the improved formwork panel unit 10,10’ as embodied in the invention is thereby characterized in that the second side edge 22b is also made outwardly tapered as shown in FIGs. 1A, 1.1 A and 1B.1.1B such that the reinforced grooves 22 are interposed in between the resulting pair of oppositely and outwardly directed tapered first side edge 22a and tapered second side edge 22b whose respective intersections with the smooth inner surface 12 and ribbed outer surface 14, specifically peripheral rib(s) 16c, correspondingly define or form tapered/convergent corner edges 22a’ (common for the panel units 10,10’) and 22b’, 22b”, respectively. In assembly, the panel units 10’s,10”s corner edges 22a’ and 22b’, 22b” are normally abutted face-to-face or edge-to-edge (for the panel units 10) against each other, or just made nearly close to each other (for the panel units 10’) but still eventually abutted against each other after tightening of panel units 10’, resulting in and/or defining a gap 24 in between the adjoined/jointed panel units 10,10’ which allows, in combination with the unused spaced apart apertures 26, self-draining of wet concrete or slurry penetrating thereinto in usage. The gap 24 has oppositely directed and outwardly convergent tapered end portions 24’ terminating oppositely at the abutted or non-abutted comer edges 22a’, 22b’ as shown in FIGs. 1 A, 1.1 A and 1 B.1.1B.

With the corner angularities and edge sharpness of the tapered side edges 22a, 22b and comer edges 22a’ and 22b’, 22b” (most especially and/or preferably the side and corner edges 22a, 22a’ bounding the panel unit’s inner surface 12), the abutted side and comer edges 22a, 22a’ at the inner surface 12 define and/or form at least substantially, if not perfectly, seamless and/or grooveless panel joint(s) 25 for both the panel units 10,10’. Thus, the adjacently jointing of several formwork panels or panel units 10,10’ for use as shuttering form produces a smooth concrete formed surface (not shown) having negligible, if not totally unrecognizable, joint marks.

As main teaching and improvement introduced by the invention, as differentiated from the features of the conventional formwork panel 10” shown in FIG. 1C which has its second side edge 22d being non-tapered or straight such that the space-apart, non-tapered corner edges 22d’ of the jointed formwork panel units 10” are forcibly made closer but not abutted against each other in assembly as a result of structural or installation tightening of panel units, especially those of panel units 10’. While being made closer to each other, there is defined between panel units 10” an open end gap portion 24” whose presence would likely undermine the structural stability of the jointed panel units 10”. Unlike the structural set-up of the prior art, the corner edges 22b’, 22b” of the second side edges 22b of the jointed present formwork panel units 10,10’ are abutted face-to-face against each other in assembly or when installed onsite, either naturally/initially (for panel units 10) or consequently from joint tightening (for panel units 10’).

As shown in FIG. 1B, due to the symmetrical position/disposition and/or structural set-up of the opposite abutted corner edges 22a’ and 22b’ in assembly, the edge-to-edge abutment of the corner edges 22b’, which is also along or at the line of contact of that of the corner edges 22a’, securely effects and ensures a tight fit jointing or abutment of the corner edges 22a’ or jointed panel units 10. For the panel units 10’ shown in FIG. 1.1B, they have significantly much closer side and corner edges 22b, 22b” in assembly than those of the existing panel units 10” due to the former’s edges’ being convergently tapered, thereby defining a corner edges’ gap C’ that is much narrower than the corresponding gap C of the panel units 10”. Being with such very narrow gap C’, the jointed panel units 10’ can readily abut against each other as consequence of panels assembly tightening. With both the panel units 10,10’, there results a significantly increased and much improved stability, durability and/or joint(s) accuracy of the comer edges 22a’ of the smooth inner surfaces 12 of the jointed/installed formwork panel units 10,10’, especially the more preferred panel units 10, thereby reliably producing substantially, if not completely, seamless/grooveless quality formed concrete. Such structural assembly or jointed panel units 10’s,10”s set-up, i.e. the opposite and/or symmetrical abutments of the respective corner edges 22a’ and 22b’, 22b”, eliminate any instability tendencies and/or unwanted movement or displacement of the jointed formwork panel units 10,10’ that are preferably installed onsite together with supporting elements/components securely and stably mounted at the ribbed outer surfaces 14 such as joists, walers, corner frame supports, support members and stiffeners, etc.

Further, when the formwork panel units 10” of the prior art are jointed together using the connecting means 15 tightly clamping/fastening together their respective peripheral ribs 16c, thus, closely, if not abuttingly, bringing their spaced apart non-tapered comer edges 22d’ together, the abutment of their tapered/convergent corner edges 22c’ as shown in FIG. 1C would not be in an accurately direct face-to-face position and/or precisely/perfectly flattened jointed smooth inner surfaces 12 resulting in relatively/slightly wider panel joint(s) 25, and consequently, unwanted more recognizable/visible formed concrete joint mark(s), which may not likely be desirable/acceptable where accuracy and high quality of formed concrete are of important/critical consideration forming part of the building construction standards/requirements.

The abutment or bringing together of the space-apart, non-tapered corner edges 22d’ by clamping slightly tilts A the panel units 10” as shown in FIG. 1C, resulting in slight bends or bulges on the inner surfaces 12 (such bulges/bends becoming larger across a plurality of jointed panel units 10”) due to unbalanced, non-symmetrical corner edges’ displacement and/or abutment, which results in slightly non-flattened or bulging inner surfaces 12, and consequently, uneven formed concrete surfaces in cases where the weight of poured wet concrete or mortar fails or is not sufficient enough to push back the bulgingly bent inner surfaces 12. With the securely balanced and/or symmetrical abutment of the tapered corner edges 22b’ and 22a’ of the present jointed panel units 10, there results accurately and/or perfectly flattened (nonbulging) abutted jointed smooth inner surfaces 12 and at least substantially, if not perfectly, seamless and/or grooveless panel joint(s) 25 that produces completely flat and even formed concrete surfaces.

Shown in FIGs. 1, 1.1 and 2, the formwork panel unit 10,10’ generally comprises as part of the elements/features of the prior art a planar face sheet 11 having the smooth inner surface 12 and ribbed outer surface 14. The smooth inner surface 12 has no ribs and it is an internal surface of the formwork panel unit 10,10’ in contact with the poured concrete in usage. The outer surface 14 is provided with plurality of ribs 16 integrally formed on the outer surface 14 of the face sheet 11. The plurality of ribs 16 includes cross- linked or criss-crossedly arranged or disposed longitudinal ribs 16a and lateral ribs 16b resulting in a tridimensional latticework rib structure 17, forming substantially matrical hollow sections or box-like compartments 19. Further, a plurality of reinforced ribs 18 is integrally provided as projected portions formed and disposed within the hollow sections or compartments 19 on the outer surface 14 of the face sheet 11 as shown in FIG. 3. Particularly, the reinforced rib 18 includes a substantially reinforced ring 18a with radially extending stiffeners 18b integrally protruded from the outer surface

14 as an additional reinforcement to the face sheet 11 or the formwork panel unit 10 that can be subjected to heavy loading and/or impact onsite such as poured concrete, sudden impact such as hammering, or dropping object such as steel bars. The reinforced ring 18a enables desired tie hole to be made therewithin to receive a tie rod (not shown) and resist surface elongation tendency caused by repetitive usage of tie rod. The reinforced ring 18a further strengthens the face sheet 11 so that it can be re-used for a reasonable number of times. Moreover, the radially extending stiffeners 18b of the reinforced rib 18 further increase the formwork panel unit’s resistance to deflection or pillowing when filled up with concrete/mortar.

By way of example and not by way of limitation, the connecting means

15 may be of, for example, a general type of pin and wedge fastener 50 incorporated with the predetermined spaced apart aperture 26 to connect two or more formwork panel units 10 as shown in FIG. 3. The pin and wedge fastener 50 is known in the art and will not be described herein in details. The connecting means may also be of, for example, a metal or plastic form clamping device 60, for fixing two or more formwork panel units 10,10’ at their abutting side frames 20 as shown in FIG. 4. Such clamping device 60 is commonly used and also known as "P-clamp".

The standard formwork panel units 10,10’ may be of varying sizes depending on the user’s or builder’s requirements and/or on area of use. Preferably, the standard formwork panel unit 10,10’ is made of plastic material such as polyethylene (PE) and/or polypropylene (PP) preferably by injection molding, mixed with composite materials. The composite materials may include, for example, coupling and foaming agents serving to improve impact strength of the formwork panel unit 10,10’; plasticizers and surface active agent serving as anti-bonding element for non-adhesive or non-stick to concrete feature. UV stabilizers may also be included to prevent aging of the formwork panel unit 10,10’. Also, the formwork panel unit 10,10’ may Include additional cut-off lines (not shown) whereby it can be easily cut into smaller sections or required sizes depending on architectural requirement or on the area of use. The cut-offline may be a predefined groove serving as a guide for a cutting device formed along the longitudinal and/or lateral direction of the formwork panel unit 10,10’.

It is most preferred that the formwork panel unit 10,10’, especially its smooth inner surfaces 12, is non-adhesive or non-stick to concrete, providing a favorable/smooth surface finish to the wall when concrete is cured. As a result, no further secondary processes, such as surface cleaning and maintenance are required to the formwork panel unit(s) 10,10’. Having smooth inner surfaces 12, the jointed panel units 10,10’ may not need any release agent in dismantling them from the formed concrete, hence, reducing operation cost as well as maintenance cost.

Furthermore, in usage, the modular formwork panel units 10,10’ can readily be used together with construction support accessory and/or other necessary construction components/materials mainly for casting in place of concrete/mortar onsite, which can be quickly put or installed in place prior to pouring of wet concrete. The installed and/or assemblage of the invention and construction support accessory can be quickly and easily removed or dismantled in re-usable condition after the formed concrete is cured. The construction support accessory also provides a rigid, firm connection in communication and/or combination with the formwork panel units 10,10’.

Before defining the scope of the following claims, it is to be understood that the invention is not limited in its applications to the details of the illustrative examples or variations set forth in the preceding description and drawings. It is to be noted that the invention is capable of other variations and limitless applications not disclosed herein. Further, this invention is likewise capable of being practiced and carried out in various ways falling within the teaching, principle and scope of the following claims.