A SYSTEM OF FORMWORK AND CONNECTING MEANS

FIELD OF INVENTION The present invention relates to a formwork system, more particularly to a system with plurality plastic formworks and connecting means for forming concrete structures such as walls, foundation, pillars, beams, slabs or the like.

BACKGROUND OF INVENTION Concrete forming apparatus is widely use in construction of buildings, bridges, and other concrete structures. A common system for forming concrete structures uses a plurality of modular form components that are adapted to be assembled into a wide variety of configurations to conform virtually any architectural requirement. Such forming apparatus components are typically made of metal so that they are adequately strong to support pressure from poured concrete and durable so that the components can be reused many times.

One of the most common used configurations of forming apparatus component is a flat panel that is used in forming substantially flat concrete surfaces, for examples, walls, foundations, pillars, beams, slabs or the like. Such forming panels have a face sheet which is in contact with the concrete being poured. A rearwardly extended flange is secured around the perimeter of the face sheet. Pluralities of spaced apart stiffeners are tied to the perimeter flange and tie rods or similar components are used to tie the flanges to the flanges of the wall panel on the opposite side of the wall being formed. Since the face sheet spans rib to rib, the welded stiffeners induce compression stress in the face sheets, particularly when force is exerted against the face sheet by the concrete. If the compression force is large enough, the face sheet will deflect between the ribs and the finished concrete will have a pillowed appearance. Walers, external stiffeners and the like are attached to the back side of the forming panel in an effort to reduce the compression forces induced on the face panel and thereby reduce the likelihood that it will deflect.

Another conventional concrete form is composed of a frame having two pairs of parallel outer steel rails, one pair of rails being perpendicular to the other pair of rails so as to form a rectangular frame. The frame may have a number of parallel inner rails which are connected to the outer-rails to form a number of rectangular bays within the frame. A concrete-forming plate, which may be plywood for example, is secured to the frame. Such conventional concrete forms are typically positioned adjacent to each other, and sometimes on top of each other, to form cavities of various shapes and sizes into which wet concrete is poured. When positioned, the concrete forms are securely fastened together by the means such as metal clamp jaws, slot-in knobs, bolts and nuts or wedges which may securely engageable to holes or slots formed in the outer rails of adjacent concrete forms so that the pressure of the wet concrete does not alter the position of the concrete forms.

Horizontally spaced vertical stiffeners or strong backs are then provided outwardly of each plywood panel to provide major strengthening for the panel support structure. Elongate beams or walers are also provided to extend horizontally along the outer side of each panel. An outwardly opening pocket formed as part of the waler retains a wooden nailer to which plywood form panel can be nailed, screwed or otherwise fastened to the waler. When the concrete dries, the concrete forms are removed and can be reused.

The use of the tie rods, metal clamp jaws, slot-in knobs, bolts and nuts or wedges for joining the metal concrete forms are time consuming especially when larger concrete surfaces or walls are need to be constructed. Moreover, said tie rods, bolt and nuts or wedges are inconvenient to use as concrete forms have to be dismantled and removed for reuse when the concrete is desiccated. Besides that, metal clamp jaw exhibits versatility limits with regard to different configurations of beams and/or pillars to be formed. Said metal clamp jaw is relatively complex and its dimensions and weight are the issue to be considered. In addition, metal forms are heavy and require stronger, more expensive equipment to move around the construction site and make the forms more difficult to maneuver into place by workers.

It is a principle object of the present invention, therefore to provide improved formwork system with plurality of plastic formwork and connecting means for forming concrete structures, which is simple, light-weight, high reliability and sturdiness, and concomitantly providing versatility or flexibility in a manner such as to employ the connecting means and the formwork panels for any desired size or arrangement for constructing the concrete structures. In addition, plastic formwork provides lower upfront cost as compare to metal formwork, low maintenance and does not require any release agent for surface clean-up.

SUMMARY OF INVENTION

A formwork system for forming concrete structure such as walls, foundation, pillars, beams or slabs comprising a plurality of formworks adapted for being connected to each other, said formworks associate with plurality of connecting means and reinforcing elements forming a system for concrete construction characterized in that the formwork system includes a) formworks having a panel surface at one side, other side of the panel surface is provided with a plurality of ribs forming a rigid rib structure, said formworks further includes plurality of apertures spaced apart along the perimeter of the formwork at predetermined distance to receive connecting means; and b) the connecting means having a body with integrally formed protruded arm at one end, said protruded arm having an elongated member transversally projected from its distal end, and bottom portion of said body is provided with integrally formed projected clamping members extending therefrom.

The formwork is moulded with predetermined cut-off lines so that said formwork can be cut into smaller sections as required. The formwork can also be moulded in a standard predetermined size without the cut-off lines. The plurality of ribs of said formworks are formed by plurality of longitudinal ribs and lateral ribs. Preferably, the formworks are made of Polyethylene (PE), Polypropylene (PP) or engineering plastic material. The apertures disposed at perimeter of the formwork are of size adapted to serve as engaging means to receive the connecting means.

Body of the connecting means can be of I- , L- , T- or cross-shaped configuration with at least one, two, three or four pair(s) of integrally formed projected clamping members respectively. The pair of integrally formed clamping members from the body of connecting means is preferably tapered from the bottom portion of the body to its distal end. The clamping members are further provided with reinforced ribs disposed at the projected portion of the clamping members. The elongated member of the connecting means is served as insertion pin to ensure the apertures of two adjacent form works and/or sectional form works are aligned, and to prevent said formworks and/or sectional formworks from any shear or sliding off movements; and the connecting means is preferably made of engineering plastic material.

BRIEF DESCRIPTION OF DRAWINGS

The drawings constitute a part of this specification and include an exemplary or preferred embodiment 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.

In the appended drawings: FIG. 1 is a perspective view illustrating a standard molded formwork according to the preferred embodiment of the present invention.

FIG. 2 is a perspective view illustrating another type of molded formwork which can be cut into smaller size or into required size.

FIG. 3 is a perspective view illustrating sectional formworks and connecting means according to the preferred embodiment of the present invention.

FIG. 4 is a perspective view illustrating sectional formworks and connecting means in a mutually fixedly connected state.

FIG. 5 is an enlarged perspective view illustrating the manner in which connecting means securely engaged at adjoining portion of the sectional formworks shown in FIG. 4.

FIG. 6 is a perspective view illustrating the connecting means according to the preferred embodiment of the present invention.

- FIG. 7 is another perspective view illustrating the connecting means view from different angle of FIG. 6.

FIG. 8 is a perspective view illustrating formwork system for making concrete surfaces or walls. FIG. 9 is a perspective view illustrating formwork system for making pillars or columns.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A detailed description of preferred embodiments of the invention is disclosed herein. It should be understood, however, the disclosed preferred embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the details disclosed herein are not to be interpreted as limiting, but merely as the basis for the claims and for teaching one skilled in the art of the invention.

Referring to FIG. 1, there is shown generally a first embodiment of formwork (10) formed according to the present invention. The formwork (10) is preferably made of plastic material, for example engineering plastic which is stamped or injection moulded in substantially quadrilateral shape. Said formwork (10) is preferably formed in a standard size of 1.2m x 0.6m which comprises a plane panel with a plurality of ribs (11) on front surface (12) of the plane panel. However, larger or smaller dimension of formwork (10) may be formed. Rear surface (13) of the plane panel has no ribs and is an internal surface of the formwork (10), that is, the surface in direct contact with the concrete. The plurality of ribs (11) is preferably perpendicular to the front surface (12). Particularly, the front surface (12) is provided with a plurality of longitudinal ribs (Ha) and lateral ribs (lib) so that square or rectangular sections are establish to form a rigid rib structure.

There is provided with a plurality of apertures (14) disposed along the perimeter of the formwork (10) at predetermined distance according to uses or arrangements of the form works. Said apertures (14) are equally formed along outer longitudinal and lateral edges (16, 18) of the formwork (10). The apertures (14) are

sized and adapted to serve as an engaging means for formwork (10) to receive the connecting means (50).

Referring now to FIG.2, there is shown another type of formwork (30) formed according to preferred embodiment of the present invention. Said formwork

(30) is substantially similar to formwork (10) as discussed above. The formwork (30) comprises a plane panel with a plurality of ribs (31) on front surface (32) of the plane panel. Rear surface (33) of the plane panel has no ribs and is an internal surface of the formwork (30), that is, the surface in direct contact with the concrete. The plurality of ribs (31) is preferably perpendicular to the front surface (32). In particular, the front surface (32) is provided with a plurality of longitudinal ribs (31a) and lateral ribs (31b) so that square or rectangular sections establish rigid rib frame.

The formwork (30) also preferably made of plastic material, for example Polyethylene (PE), Polypropylene (PP) or engineering plastic which is stamped or injection moulded in substantially quadrilateral shape. Said formwork (30) preferably formed in a standard size of 1.2m x 0.6m, but includes additional aspect such that the formwork (30) can be cut into smaller sections as required. Accordingly, said formwork (30) is having additional cut-off lines (40) to which the formwork (30) can be easily cut into smaller sections. Said formwork (30) may also be formed in larger or smaller dimension depending on architectural requirement. Sectional formwork (42) which cut off from the formwork (30) can be varying in size. Preferably, a standard size formwork (30) can be cut into sixteen pieces of 0.15m x 0.3m sectional formworks (42). However, any other sizes may be cut as necessary.

There is provided with a plurality of apertures (34) disposed along the perimeter of the formwork (30) at predetermined distance according to the uses or arrangements of the formworks. Accordingly, plurality of apertures (34) is evenly formed on the outer longitudinal and lateral edges (36, 38) of the formwork (30). Additional apertures (34) may be formed at perimeter of the cut-off sectional formwork (42). Said apertures (34) are sized and adapted to serve as an engaging means for formwork (30) to receive the connecting means (50).

Referring to FIG. 3, 4 and 5, the sectional formworks (42) can be uniformly connected by their longitudinal and lateral edges thereof by placing the sectional formworks (42) side-by-side in such manner that each cut off sectional formworks (42) are arranged adjacent to each other. The cut off sectional formworks (30) may be connected into required configuration and size by the means of connecting means (50). When constructing larger surfaces of wall or a floor, numerous standard formworks (10) can be connected at the outer longitudinal edges (16) and/or lateral edges (18) in cooperating with said connecting means (50).

The connecting means (50) allow plurality of formworks (10) and/or sectional formworks (42) to be connected. Particularly, said connecting means (50) allow arrangement of two or more adjacent formworks (10) and/or sectional formworks (42) to be connected according to any kind of sizes and configurations of structure to be formed. Referring to FIG. 6 and 7, the connecting means (50) generally comprises a body (51), at least one pair of integrally formed clamping members (52) extended from the body (51) and an integrally formed protruded arm (53) with an elongated member (54) disposed at one end of the body (51). The connecting means (50) is preferably made of plastic material, for example engineering plastic. The body (51) of the connecting means (50) is preferably of I-shaped configuration or of elongated rigid panel which having a plane surface on top and substantially curve surface on its bottom. Said body (51) is not limited to I-shaped configuration, but can be of any configuration such as L-shaped, T-shaped or cross-shaped configuration provided the body is disposed with appropriate pair of clamping members (not shown). Accordingly, I-shaped body may has at least one pair of integrally formed projected clamping members (52) extending from its bottom portion; L-shaped body may has at least two pair of integrally formed projected clamping members (52) extending from its bottom portion; T-shaped body may has at least three pair of integrally formed projected clamping members (52) extending from its bottom portion and; cross-shaped body may has at least four pair of integrally formed projected clamping members (52) extending from its bottom portion.

In following description, connecting means (50) with I-shaped body configuration is described. Referring to FIG. 6 and 7, the connecting means (50) of I- shaped body (51) is provided with two pair of clamping members (52) extending from the bottom surface of the body (51). Accordingly, clamping members (52) are integrally formed projected portions having tapered angle projecting from the bottom surface of the body (51). There is provided with reinforced ribs (52a) disposed at the said projected portions of the clamping members (52) so that more rigid structure is formed. It will be appreciated that one distal end of I-shaped body (51) is provided with integrally formed protruded arm (53). Said protruded arm (53) further provided with an elongated member (54) trans versally projected from its distal end.

The elongated member (54) serves as insertion pin to ensure apertures of two adjacent formworks (10) and/or sectional formworks (42) are being aligned, so that said adjacent formworks (10) and/or sectional formworks (42) are positioned into desired position. Said elongated member (54) of the connecting means (50) also prevent formworks from any shear or sliding off movements. Accordingly, the elongated member (54) prevents the defection caused by the compression stress on the rear surface (13) sheet of the formworks, specifically when force is exerted against the rear surface (13) sheet by poured wet concrete. The clamping members (52) of the connecting means (50) are then being pushed so that they are securely engaged onto the flanges of two adjacent formworks (10) and/or sectional formworks (42) that meeting at perimeter edges (FIG. 5). In particular, the two adjacent formworks are first aligned by the insertion of the elongated member (54) through the apertures disposed along the perimeter of the formworks and the clamping members (52) are then being pressed onto the perimeter flanges of two adjoined formworks so that the formworks are securely connected. It will be appreciated that each connecting means (50) requiring just a single hammer blow to join or to release the connection of the formworks.

By way of example and not by way of limitation, FIG. 8 and 9 illustrate the use of the formworks (10) and/or sectional formworks (42) incorporating with connecting means (50) to form a system for constructing concrete structure such as

walls, foundation, pillars, beams, slabs or the like. When constructing larger surfaces of a wall, foundation, pillar, beam, slab or the like, plurality of formworks (10) and/or sectional formworks (42) can be connected by the outer longitudinal edges (16) and/or by the outer lateral edges (18). Said formworks are incorporated with plurality of connecting means (50) and reinforcing elements (60) to form a plastic light weight formwork system as shown in FIG. 8 and 9. The reinforcing elements (60) generally comprising support members which formed by plurality of vertical support bars (61) and horizontal support bars (62). Said vertical support bars (61) and horizontal support bars (62) are established to form a rigid frame by means of fastening means (63). There are provided supporting rods or pipe bracings (64) engageable on the horizontal support bars (62) to support or to stabilize the formwork system. Said supporting rods or pipe bracings (64) allow vertically adjustment so that the formwork can be raised up vertically. In the case of constructing pillars, angle bars (70) are preferably used. Said angle bars (70) are served to effect a firm connection between the complementary sections of two formworks by means of connecting means (50).

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the principle and scope of the invention, and all such modifications as would obvious to one skilled in the art intended to be included within the scope of following claims.