WO2024124283A1

WO2024124283A1 - An inside corner form assembly and method of stripping thereof

Info

Publication number: WO2024124283A1
Application number: PCT/AU2023/051256
Authority: WO
Inventors: Patrick Doherty
Original assignee: Patrick Doherty
Priority date: 2022-12-16
Filing date: 2023-12-05
Publication date: 2024-06-20

Abstract

An inside corner form assembly for casting a concrete corner, the assembly withdrawable from interior walls of the concrete corner to facilitate stripping of the assembly. The assembly comprises: a vertically extending corner component having an angled exterior comprising a pair of planar surfaces defining an inner corner; and a pair of vertically extending wall panels, each having an exterior face for defining a respective wall of the corner. The corner component is movably secured between and movable relative to the wall panels from: a setting configuration where each planar surface of the corner component is coplanar with the respective planar face of the adjacent wall panels such that the planar surfaces and the planar faces define a continuous and vertically extending corner; and a stripping configuration in which the planar surfaces of the corner component are withdrawn inwardly away from the corner to facilitate stripping.

Description

An inside corner form assembly and method of stripping thereof

Field of the invention

Disclosed herein is an inside corner form assembly used in forming concrete structures with one or more corners. The assembly may cooperate with like assemblies to form a concrete form around which a concrete structure can be cast. The assembly is configured such that it can then be stripped from the cast concrete structure. Also disclosed herein is a method for stripping said form from the concrete structure.

Background

Concrete structures with corners, such as right angle corners, are usually formed via two sets of forms; an inside corner form and a corresponding outside corner form between which concrete can be poured. Once the concrete has set, the outside form can be readily removed (stripped) from the concrete structure. However, the inside form can be difficult to strip due to the pressure exerted thereon by the inside walls of the concrete structure.

Existing inside corner form assemblies and systems (also known as "stripping" corner options) are commonly adapted for industrial applications, and are relatively expensive, utilise numerous components, require extensive assembly and disassembly, and often require specialised tools to configure and strip, such as hydraulic power systems. Moreover, such inside corner form assemblies and systems are not adapted for nor economically feasible for smaller concrete structures. Other ways of stripping a pit often involve rigid corner assemblies that require larger amounts of work and thus time and risk on the part of the operator. Additionally, installation and operation of existing assemblies and the like can be relatively dangerous and may require users to perform complex tasks from within the concrete structure and/or formwork itself.

There is a need to address the above, and/or at least provide a useful alternative. According to a first aspect of the present invention, there is provided an inside corner form assembly around an exterior of which a concrete corner can be cast, the assembly being configurable to be withdrawn from interior walls of the concrete corner to facilitate stripping of the assembly therefrom, the assembly comprising: a vertically extending corner component having an angled exterior comprising a pair of planar surfaces meeting generally at a right angle for defining an inner corner of the concrete to be cast; and a pair of vertically extending wall panels, each having an exterior planar face for defining a respective wall of the concrete corner to be cast, wherein in use, the corner component is movably secured to and between the wall panels which extend generally perpendicularly to one another, the corner component being movable relative to the wall panels from: a setting configuration in which each planar surface of the corner component is coplanar with the respective planar face of the adjacent wall panels such that the planar surfaces and the planar faces together define a substantially continuous and vertically extending corner around which the concrete corner can be cast; and a stripping configuration in which the corner component and thus the planar surfaces thereof are withdrawn inwardly away from the cast concrete corner to facilitate stripping of the assembly from the concrete corner.

In certain embodiments of the present assembly, the wall panels may be secured to the corner component such that withdrawal thereof from the concrete corner acts to then draw the wall panels and thus the planar faces thereof inwardly away from the respective walls of the cast concrete corner to facilitate stripping of the assembly therefrom.

It is envisaged that the corner component may further comprise a pair of vertically extending and spaced apart planar wedge faces, each extending from and angled inwardly from a respective planar surface of the corner component; and that each wall panel may comprise a vertically extending planar angled face configured to slidably engage a respective wedge face such that, in use, the corner component is wedged between the respective angled faces of the wall panels whereby withdrawal of the corner component from the concrete corner correspondingly draws the wall panels away from the respective walls of the concrete corner.

In embodiments of the present assembly, the wedge faces of the corner component and the interfacing angled faces of the wall panels may be slidably linked via a fastener secured to either the corner component or the wall panels, which fastener extends through and travels along a horizontal slot of the other one of the corner component or the wall panels.

In at least one example embodiment, the corner component may be configured to be leverable from the setting configuration to the stripping configuration. For example, the assembly may comprise a rocker configured to receive a shaft therein to facilitate the levering of the corner component away from the concrete corner. Preferably, the rocker is disposed between and pivotally engaged with each wall panel about a pivot axis, the rocker also being operably engaged with the corner component such that, in use, levering the rocker about its pivot axis withdraws the corner component away from the concrete corner.

It is envisaged that the rocker is operably engaged with the corner component via an over-centre linkage configured to impede the corner component, under pressure from concrete poured therearound, from moving from the setting configuration toward the stripping configuration.

According to a second aspect of the present invention, there is provided a concrete form comprising one or more inside corner form assemblies according to a first aspect of the present invention. In one particular example, four assemblies may be arranged to define a rectangular-shaped concrete form wherein each of the four corner components defines an inner corner of the rectangular concrete structure to be cast, wherein, in the setting configuration, each wall panel of each assembly is arranged to be coplanar with a wall panel of an adjacent assembly.

According to a third aspect of the present invention, there is provided a method of stripping a concrete form according to a second aspect of the present invention, comprising: manually levering each corner component inwardly and away from the respective corners of the concrete structure cast around the form; and lifting the form vertically upward and out of the concrete structure.

Brief description of the drawings

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Fig. 1 is a top perspective view of an inside corner form assembly according to embodiments of the present invention, the assembly shown in a setting configuration;

Fig. 2A is a top in-situ view of the assembly of Fig. 1 being used to form an inside corner of a concrete structure;

Fig. 2B is a top in-situ view of the assembly of Fig. 2A, the assembly shown in a stripping configuration wherein the assembly is withdrawn from inside walls of the concrete structure;

Fig. 3 is a top perspective view of a concrete form comprising four of the assemblies of Fig. 1 arranged in a square-shaped form;

Fig. 4A is a top view of the concrete form of Fig. 3;

Fig. 4B is a top view of the concrete form of Fig. 4A, the assemblies thereof in the stripping configuration;

Fig. 5A is a side perspective view of a corner component of the assembly of Fig. 1; Fig. 5B is a front perspective view of the corner component of Fig. 5A; Fig. 6 is a perspective view of a wall panel of the assembly of Fig. 1;

Fig. 7 is a close-up front perspective view of an upper end of the assembly of Fig. 1;

Fig. 8 is a close-up front perspective view of the assembly of Fig. 1 showing a rocking mechanism thereof;

Fig. 9 is a close-up top perspective view of the rocker mechanism of Fig. 8, wherein certain parts of the corner component and a wall panel are hidden;

Fig. 10 is a close-up bottom perspective view of the rocker mechanism of Fig. 9;

Fig. 11 is a top perspective view of the assembly of Fig. 1, the assembly shown in a stripping configuration;

Fig. 12 is a close-up top perspective view of the rocker mechanism wherein certain parts of the corner component and a wall panel are hidden; and

Fig. 13 is a close-up bottom perspective view of the rocker mechanism of Fig. 12.

Detailed

Fig. 1 shows an inside corner form assembly 2 according to embodiments of the present invention. The assembly 2 comprises a vertically extending corner component 4 arranged between a pair of vertically extending wall panels 6. In use, concrete is poured around an exterior of the assembly to form a corner 8 of a concrete structure 10; this is shown in Fig. 2A, wherein the assembly 2 is configured in a setting configuration.

Referring to Fig. 2B, once the concrete structure 10 has set, the assembly 2 can be moved to a stripping configuration wherein the assembly 2 can be stripped (e.g., withdrawn or released) from the interior walls 12 and corner 8 of the concrete structure 10, whereupon the assembly 2 can be lifted out from the structure 10, ready for use in forming other concrete structures.

Figs. 3 shows an example of four such assemblies 2 arranged to form a generally square-shaped concrete form 14, wherein the wall panels 6 of each assembly 2 are arranged adjacent to respective wall panels 6 of an adjacent assembly 2 such that the four corner components 4 face inward toward the centre of the square-shaped concrete form 14.

Fig. 4A shows the four assemblies 2 in their respective setting configurations, around which a square-shaped concrete structure can be formed. Fig. 4B shows the four assemblies 2 in their respective stripping configurations, wherein the corner components 4 and wall panels 6 are drawn in (toward the centre of the square-shaped concrete form 14) and away from the inside walls 12 of the concrete structure 10, thereby permitting withdrawal of the assemblies 2 therefrom.

Figs. 5A and 5B show an embodiment of a corner component 4 in isolation. In use, the corner component 4 is configured to extend vertically upward to facilitate the forming of an inside corner 8 of the concrete structure 10 to be cast therearound. The corner component 4 is generally in the form of a substantially hollow channel having a footprint and cross-sectional shape (taken along the longitudinal axis) that is generally in the form of an irregular pentagon, the perimeter of the pentagonal shape being defined by: a pair of vertically extending planar surfaces 16 which meet at a right angle 18 which facilitates the formation of the inside corner 8 of the concrete structure 10; a pair of vertically extending and spaced apart planar wedge faces 20 which extend from and are angled inwardly from a respective planar surface 16 of the corner component 4; and an imaginary 'base' of the pentagon as indicated by the dotted line at an upper end of the corner component 4 in Fig. 5B.

As can be seen in Fig. 4A, the pair of planar surfaces 16 meet at a right-angle corner 18 which forms a corresponding inside corner 8 of the concrete structure 10 to be cast. Meanwhile, and as will be discussed, each planar wedge face 20 of the corner component 4 is configured to receive thereagainst a respective planar angled face 22 of a wall panel 6 of the assembly 2. Referring back to Figs. 5A and 5B, spaced along a height of each wedge face 20 of the corner component 4 is a series of fasteners 24 that extend transversely through the wedge faces 20. In the depicted embodiment, the fasteners are in the form of studs 24 whose heads are arranged at an interior of the wedge faces 20 with the corresponding rod portions extending out through at an exterior of the wedge faces 20. As will be discussed, it is via these fasteners 24 that the corner component 4 is engaged with the wall panels 6 in a manner that enables relative movement therebetween.

Fig. 6 shows an embodiment of a wall panel 6 in isolation. In use, the wall panel 6 is configured to extend vertically upward to facilitate the forming of a planar wall of the concrete structure 10 to be cast therearound. The corner component 4 is generally in the form of a substantially hollow channel having a footprint and cross-sectional shape (taken along its longitudinal axis) that is generally in the form of an irregular quadrilateral. Referring also to Fig. 4A, a perimeter of the irregular quadrilateral is defined by: an exterior planar face 26 for forming an inside wall of the concrete structure 10 to be cast; an interior planar end 28 that faces inward toward a centre of the concrete form 14; an end face 28 configured to be received against a corresponding end face 28 of an adjacent wall panel 6 of an adjacent inside corner form assembly 2; and a vertically extending planar angled face 22 which, in use, is arranged to face and almost engage against a corresponding wedge face 20 of the corner component 4.

Referring to Fig. 6, spaced along a height of the planar angled face 22 of the wall panel 6 is a series of elongate slots 32 extending transversely to the height of the angled face 22. Each slot 32 is positioned at heights that correspond to the heights of the studs 24 extending through the corner component 4. Referring to Fig. 7, when assembled, the rod portion of each stud 24 is configured to extend through a respective slot 32 of an adjacent wall panel 6. As will be discussed, this fastener 24 and slot 32 engagement enables relative movement between the corner component 4 and the adjacent wall panels 6. In particular, the corner component 4 can be withdrawn away from the inside corner 8 of the concrete structure 10, whereby the corner component 4 slides inwardly (e.g., toward a centre of the square-shaped concrete form 14 of Fig. 2B), which sliding motion is guided by a sliding movement of the rod ends of the studs 24 through the corresponding elongate slots 32 of the adjacent wall panels 6.

Referring to Figs. 2A, the assembly 2 is shown in the setting configuration wherein the corner component 4 is wedged between the pair of adjacent wall panels 6. In the depicted embodiment, a small, vertically extending gap 34 is maintained between the planar wedge faces 20 of the corner component 4 and the respective planar angled faces 22 of the wall panels 6 (e.g., via respective washers 36 through which the studs 24 extend, shown in Fig. 5A). Moreover, the engagement of the fasteners 24 of the corner component 4 and the elongate slots 32 of the wall panels 6 is such that as the assembly 2 is moved from the setting configuration (Fig. 2A) to the stripping configuration (Fig. 2B), the width of the vertically extending gap 34 between the wall panels 6 and the corner component 2 is maintained. As such, while the fasteners 24 allow for relative lateral movement between the corner component 4 and the wall panels 6 (e.g., as though the wall panels 6 and corner component 4 smear against one another when moving from the setting to the stripping configurations), the fasteners 24 restrict against relative transverse movement between the planar wedge faces 20 of the corner component 4 and the adjacent planar angled faces 22 of the wall panels 6. In so doing, as the corner component 4 is withdrawn inwardly away from the inside corner 8 of the concrete structure 10 (as per Fig. 2B), this movement of the corner component 4 also acts to draw the wall panels 6 inwardly in a direction away from the inside walls of the concrete structure 10. As such, the corner component 4 and wall panels 6 of the present assembly 2 need not be individually stripped from the concrete structure 10. Instead, the corner component 4 and the wall panels 6 are functionally engaged with one another such that withdrawal of the corner component 4 also acts to withdraw the wall panels 6, thereby facilitating a simpler and more efficient method of stripping the assembly 2 from the concrete structure 10. Figs. 8 to 10 show close-up views of a mechanism 38 operable to move the assembly 2 from the setting configuration to the stripping configuration. In particular, it is envisaged that the mechanism 38 can be levered (e.g., manually) to withdraw the corner component 4 and thus strip the assembly 2 from the concrete structure 10.

The depicted mechanism 38 comprises a substantially hollow L-shaped rocker 40 which interconnects the corner component 4 and the wall panels 6. To this end, and with reference to Fig. 6, each wall panel 6 has a central flange 42 that is coplanar with and protrudes inwardly from the planar angled face 22 of the wall panel 6. Each flange 42 has a centrally disposed through hole 44. Referring to Fig. 8, the L-shaped rocker 40 is disposed between the opposed flanges 42 of respective wall panels 6, the rocker 40 being held pivotably in place via a pin 46 that passes through the elbow of the L-shaped rocker 40 and the respective through holes 44 of the flanges 42. The pin 46 is configured to rotate about its longitudinal axis within the through holes 44 of the flanges 42 and thus defines an axis about which the rocker 40 can pivot.

Referring back to Fig. 5B, a central portion of the corner component 4 along its height is provided with a pair of vertically extending plates 48, which plates 48 are disposed between the interior of the wedge faces 20 of the corner component. The plates 48 are provided with through holes 50 aligned along the height of the corner component 4 such that a pin 52 is receivable therethrough. Referring to Figs. 9 and 10, the rocker mechanism 38 of the present assembly 2 further comprises a linkage 54. A first end of the linkage 54 is disposed between the plates 48 of the corner component 4 (the rightmost plate 48 is not shown in Figs. 9, 10, 12 and 13) and is pivotally associated therewith via the pin 52 which extends therethrough. An opposite second end of the linkage 54 is disposed between the horizontally extending arms 58 of the L-shaped rocker 40 and is also pivotally associated therewith via a pin 60 extending through the horizontal arms 58 of the rocker 40 and the linkage 54. In use, the rocker 40 is levered backwards, pivoting the rocker 40 about the axis of the pin 46 extending through the elbow of the rocker 40, which pivoting motion pulls on the linkage 54 which in turn pulls on and draws the corner component 4 away from the inside corner 8 of the concrete structure 10. The resulting stripping configuration of the rocker mechanism is shown in Figs. 11 to 13.

Referring to Fig. 9, the rocker 40 is provided with a safety latch 62 that extends through a hollow vertical portion of the L-shaped rocker. To operate the rocker 40, a user can first remove the latch 62, thereby granting increased access to the hollow interior channel 64 of the rocker 40 (as shown in Fig. 11). A first end of a correspondingly shaped shaft or rod can then be inserted into the channel 64, which first end would then abut the pin 46 extending through the rocker 46, the pin 46 preventing the shaft from sliding further through the rocker channel 64 of the rocker 40. Next, the user can pull back on a second end of the shaft to lever it away from the corner component 4. This levering of the shaft acts to pivot the rocker 40 backwards about the pivot axis defined by the pin 46 extending through the elbow of the rocker 40, as shown in Fig. 11, thereby pulling on the linkage 54 and thus the corner component 4 so as to draw the corner component 4 away from the inside corner 8 of the concrete structure 10, along with the adjacent wall panels 6.

Referring also to Figs. 12 and 13, it will be appreciated that the rocker 40 and linkage 54 are arranged in an over centre-type configuration which impedes or otherwise resists movement of the assembly 2 away from the setting configuration as concrete is poured therearound. In use, the pressure of the concrete as it is poured around the assembly 2 is applied against the outer surfaces thereof, which may otherwise act to move the assembly 2 toward the stripping configuration prematurely. The aforementioned over-centre configuration helps to maintain the assembly 2 in the setting configuration during pouring and setting of the concrete. Referring to Fig. 10, as the concrete applies an inward-directed pressure against the corner component 4, the interconnection between the generally horizontally oriented linkage 54 and rocker 40 further locks the rocker 40 against rearward pivotal movement about the pin 46, effectively locking the corner component 4 from moving towards the stripping configuration prematurely before the concrete has had a chance to set. Many modifications of the above embodiments will be apparent to those skilled in the art without departing from the scope of the present invention. For example, while the depicted assembly 2 is configured to secure to other like assemblies 2 to form a squareshaped concrete form 14, the construction and sizing of the corner component 4 and wall panels 6 may of course vary to enable the formation of concrete forms having other shapes and configurations. For example, it is envisaged that the construction and configuration of the corner component 4 and wall panels 6 can be configured to form other shaped structures, including triangular-shaped concrete structures. The 'footprint' of the corner component 4 and wall panels 6 may also vary. For example, the corner component 4 may have a generally triangular cross-sectional profile along its longitudinal axis. A height of the assembly 2 may also vary to enable the formation of a concrete structure of a desired height. It is also envisaged that like assemblies 2 can be stacked on top of one another if a concrete structure of increased height is to be formed. Additionally, while the Figures show a generally L-shaped rocker 40, other shaped and similarly operable rockers are considered within the scope of the present specification, such as a T-shaped rocker.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" and "comprising", will be understood to imply the inclusion of a stated integer or step or group of integers or steps but not the exclusion of any other integer or step or group of integers or steps.

The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that that prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates.

Claims

CLAIMS:

1. An inside corner form assembly around an exterior of which a concrete corner can be cast, the assembly being configurable to be withdrawn from interior walls of the concrete corner to facilitate stripping of the assembly therefrom, the assembly comprising: a vertically extending corner component having an angled exterior comprising a pair of planar surfaces meeting generally at a right angle for defining an inner corner of the concrete to be cast; and a pair of vertically extending wall panels, each having an exterior planar face for defining a respective wall of the concrete corner to be cast, wherein in use, the corner component is movably secured to and between the wall panels which extend generally perpendicularly to one another, the corner component being movable relative to the wall panels from: a setting configuration in which each planar surface of the corner component is coplanar with the respective planar face of the adjacent wall panels such that the planar surfaces and the planar faces together define a substantially continuous and vertically extending corner around which the concrete corner can be cast; and a stripping configuration in which the corner component and thus the planar surfaces thereof are withdrawn inwardly away from the cast concrete corner to facilitate stripping of the assembly from the concrete corner.

2. The assembly of claim 1, wherein the wall panels are secured to the corner component such that withdrawal thereof from the concrete corner acts to then draw the wall panels and thus the planar faces thereof inwardly away from the respective walls of the cast concrete corner to facilitate stripping of the assembly therefrom.

3. The assembly of claim 1 or 2, wherein: the corner component further comprises a pair of vertically extending and spaced apart planar wedge faces, each extending from and angled inwardly from a respective planar surface of the corner component; and each wall panel comprises a vertically extending planar angled face configured to slidably engage a respective wedge face such that, in use, the corner component is wedged between the respective angled faces of the wall panels whereby withdrawal of the corner component from the concrete corner correspondingly draws the wall panels away from the respective walls of the concrete corner.

4. The assembly of claim 3, wherein the wedge faces of the corner component and the interfacing angled faces of the wall panels are slidably linked via a fastener secured to either the corner component or the wall panels, which fastener extends through and travels along a horizontal slot of the other one of the corner component or the wall panels.

5. The assembly of any one of the preceding claims, wherein the corner component is configured to be leverable from the setting configuration to the stripping configuration.

6. The assembly of claim 5, further comprising a rocker configured to receive a shaft therein to facilitate the levering of the corner component away from the concrete corner.

7. The assembly of claim 6, wherein the rocker is disposed between and pivotally engaged with each wall panel about a pivot axis, the rocker also being operably engaged with the corner component such that, in use, levering the rocker about its pivot axis withdraws the corner component away from the concrete corner.

8. The assembly of claim 7, wherein the rocker is operably engaged with the corner component via an over-centre linkage configured to impede the corner component, under pressure from concrete poured therearound, from moving from the setting configuration toward the stripping configuration.

9. A concrete form comprising one or more inside corner form assemblies according to any one of the preceding claims.

10. The form of claim 9, comprising four assemblies arranged to define a rectangularshaped form wherein each of the four corner components defines an inner corner of the rectangular concrete structure to be cast, wherein, in the setting configuration, each wall panel of each assembly is arranged to be coplanar with a wall panel of an adjacent assembly.

11. A method of stripping the form of claim 10, comprising: manually levering each corner component inwardly and away from the respective corners of the concrete structure cast around the form; and lifting the form vertically upward and out of the concrete structure.