Conduit device and filter vent for concrete formwork

The invention to which this application relates is a conduit device typically used for facilitating the filling of fabric or timber forms of concrete formwork and/or venting water or air therefrom.

Formwork includes rigid timber formwork, as well as fabric formwork. Fabric formwork is a means by which concrete structures can be shaped, and may comprise flexible sheet materials formed as a bag-like structure. The fabric formwork bags are filled with wet concrete, such that when the concrete cures the formwork defines the shape of the concrete structure.

Concrete may be placed into a formwork bag by hand or by pumping through a hose. Several rudimentary arrangements are known for coupling a hose to a bag, such as the provision of simple holes or sleeves within the bag. However, when the bag is filled in situ underwater there is a tendency for concrete to escape through the holes when the hose is removed as the bag is not provided with a means to prevent such escape therefrom. This results in undesirable contamination of the water by the concrete.

In addition, air and water may be displaced from the bag where the bags are used around watercourses, or underwater. However, this displacement is usually uncontrolled and can result in trapped air or water within the formwork, or undesired escape of waters contaminated with cement or concrete. The inclusion of sewn in filter points can reduce the contamination, but the points need to be incorporated into the manufacturing process and are an integral and immoveable part of the fabric formwork.

An aim of the present invention is to provide a device for reducing the risk of contamination from filling formwork with material.

In one aspect of the invention there is provided a conduit device for formwork comprising a body defining at least one passage which, when the device is fitted to formwork, allows fluid and/or matter to flow into the formwork via said passage, characterised in that said device, in an inlet configuration, allows matter to enter the formwork and prevents exit of matter from the formwork.

Typically a valve member is provided which is moveable between an open configuration to allow the flow of fluid and/or matter therethrough, and a closed configuration to prevent the flow of fluid and/or matter therethrough.

Typically the valve member is biased to the closed configuration.

Typically the valve member is moved to the open configuration when the bias is overcome by pressure from one side of the valve member.

In one embodiment the valve member is a slitted rubber dome. Typically the dome is convex when viewed from the interior of the formwork so as to resist the escape of matter therefrom.

Typically connection means are provided to allow the valve member to be removably connected and/or locked in a particular position.

Typically retaining means are provided to retain the conduit assembly in a particular position and/or orientation with respect to the formwork.

In one embodiment channel means are provided to allow matter to be directed into the passage and/or allow fluid to be directed away from the passage. Typically the channel means is a hose or pipe.

In one embodiment the body is reversible to allow the passage to be adapted into an outlet configuration depending on the orientation thereof with respect to the formwork. In this embodiment the valve member is rendered inoperable or a portion is removed to reconfigure the inlet as an outlet.

In one embodiment the conduit device is provided with two or more passages, at least one passage in an inlet configuration to allow matter to enter the formwork and prevent exit thereof, and at least one passage in an outlet configuration to allow fluid to exit the formwork.

In one embodiment the passage in the outlet configuration is provided with a filter vent for filtering fluid exiting the formwork.

In one embodiment the filter vent comprises a structure defining a channel provided with filter media for filtering fluid which passes along the channel

In one embodiment the filter media is located in the channel. Typically the structure is tubular.

In one embodiment a filter is provided associated with the channel outlet for further filtering said fluid exiting therefrom. Typically the filter is a bag-like structure.

In one embodiment, attachment means are provided for attaching the structure to formwork. Typically the filter vent is attached to the formwork externally.

In one embodiment the attachment means is any or any combination of screw fitting, push fit, bayonet mount, clips, grips, and/or the like.

In one embodiment the filter media is provided to prevent concrete and other such matter from exiting the formwork when the structure is attached thereto. Typically the structure is detached following curing of concrete placed in the formwork.

Typically the filter media selectively prevents matter of one or more predetermined sizes in the fluid passing therethrough.

In one embodiment the filter media prevents particles of progressively decreasing size from passing therethrough as fluid passes along the channel.

In one embodiment the filter media comprises one or more layers of woven or non woven fabric including pores or apertures therein.

In a further embodiment the filter media comprises foamed material, or granules of one or more predetermined sizes. Typically the granules are positioned in order of decreasing size with respect to the direction of fluid flow in the channel.

Typically the aperture size of the filter media in the structure adjacent the channel outlet is smaller than the aperture size of the filter media in the structure adjacent the channel inlet.

Typically the aperture size of the filter is smaller than the aperture size of the filter media in the structure adjacent the outlet.

In one embodiment the structure increases in cross-section along the channel. Thus the amount and/or surface area of the filter media increases as the aperture size of the same decreases.

In one embodiment the structure is flexible. In a further embodiment the structure is rigid.

In one embodiment the structure is disposable.

In a further aspect of the invention, there is provided a filter vent device for formwork as hereinabove described.

The filter vent allows matter such as concrete to be retained within the formwork while allowing fluid such as water and air to exit therefrom.

In a further aspect of the invention there is provided a conduit device for formwork comprising a body defining at least one passage said device being configurable in an inlet configuration, which, when the device is fitted to formwork, allows fluid and/or matter to flow into the formwork via said passage and prevents exit of matter from the formwork, and an outlet configuration, which, when the device is fitted to formwork, allows fluid and/ or matter to exit the formwork, wherein when configured in the outlet configuration, said device is provided with a filter vent for filtering fluid exiting the formwork

In one embodiment the filter vent comprises a tubular structure defining a channel provided with filter media for filtering fluid which passes along the channel.

In one embodiment the filter media prevents particles of progressively decreasing size from passing therethrough as fluid passes along the channel.

In one embodiment a bag-like filter is provided at the end of the channel for further filtering fluid exiting from the channel.

In a yet further aspect of the invention there is provided a method of filling formwork with matter comprising the steps of: preparing a concrete mixture; placing the formwork in a location; pumping or pouring the mixture into the formwork via an inlet passage to fill the formwork; characterised in that an inlet passage is defined as part of a conduit device fitted to the formwork, to allow the mixture to enter the formwork and prevent exit thereof.

In one embodiment an outlet passage is defined as part of the conduit device such that any fluid displaced from the formwork passes through the outlet passage and is filtered by a filter vent connected to the outlet passage.

In one embodiment the conduit device is reversible or otherwise reconfigurable to reconfigure either of the inlet or outlet pas.sages as the other.

In one embodiment the conduit device includes both an inlet passage and an outlet passage to allow concrete to enter the formwork with simultaneous exit of air and/or water therefrom.

In a further embodiment a filling hose and/or a filter vent is attached to the conduit device.

In one embodiment the location is underwater.

In one embodiment the filter vent is detached and/or disposed of following curing of concrete placed in the formwork.

Specific embodiments of the invention are now described wherein:-

Figure 1 illustrates a schematic cross-section of a conduit device according to an embodiment of the invention

Figure 2 illustrates a schematic cross-section of the body of a conduit device according to an embodiment of the invention

Figure 3 illustrates a view from above of the body of a conduit device according to an embodiment of the invention

Figure 4 illustrates a view from above of the valve of a conduit device according to an embodiment of the invention

Figure 5 illustrates a schematic cross-section of a conduit device adapted to be an inlet according to an embodiment of the invention

Figure 6 illustrates a schematic cross-section of a conduit device adapted to be an outlet according to an embodiment of the invention

Figure 7 illustrates a schematic cross-section of a conduit device in accordance with a further embodiment of the invention

Figure 8 illustrates a view from above of the body of the conduit device of Figure 7.

Figure 9 illustrates a schematic cross-section of a filter vent in accordance with an embodiment of the invention.

Figure 10 illustrates a schematic cross-section of a filter vent in accordance with an embodiment of the invention.

Figure 1 1 illustrates a filter vent in use with fabric formwork.

Figure 12 illustrates a schematic perspective view of a filter vent in accordance with a further embodiment of the invention.

Figure 13 illustrates a schematic cross-section of the filter vent of Figure 12.

Figure 14 illustrates a schematic cross-section of a filter vent in accordance with an embodiment of the invention.

Figure 15 illustrates a filter vent in use with fabric formwork.

Figure 1 illustrates a conduit device including a body portion 40 through which an inlet passage 44 is defined.

The conduit device is mounted in an opening of the formwork 11 , and held in place by retaining means in the form of lock nuts 50.

A valve member is associated with the inlet passage 44 in the form of a slitted rubber dome 46 which is moveable between an open configuration to allow the flow of fluid and/or matter

therethrough, and a closed configuration to prevent the flow of fluid and/or matter therethrough.

The device is provided with connection means in the form of a nut 48 to allow the dome 46 to be connected or detached as required.

A hose coupling 30 can be connected to the inlet passage 44 to allow a hose to be connected thereto to allow the formwork to be filled with concrete as indicated by arrow 56. The dome 46 is biased to the closed configuration due to the resilience of the rubber, but is opened under pressure from the flow of concrete from the hose. When the flow from the hose stops, the resilience of the rubber causes the dome to move to the closed configuration, which prevents leakage of concrete from the formwork.

Figure 2 illustrates the body 40 by itself, illustrating the external thread 51 to which the locking nut may be attached and an internal thread 53 to which hoses or filters can be attached. Connection means in the form of an external thread 49 are provided for receiving the nut which holds the slitted dome in position.

Figure 3 illustrates the view from above of the body 40, through which is defined an inlet passage 44.

Figure 4 illustrates the valve member 46, which has a flat edge 45 and a plurality of slits 47 which open outwardly to allow the concrete to pass through the valve.

Figure 5 illustrates the conduit device in use as an inlet. A cap 54 may be fitted to further reduce the risk of concrete leaking from the device.

However it will be appreciated by persons skilled in the art that the ends of the passage can be adapted to form either an inlet passage when the conduit assembly is in a first orientation with respect to the formwork, or an outlet passage when the conduit assembly is in a reversed, second orientation with respect to the formwork.

Figure 6 therefore illustrates the conduit device in use as an outlet in which the dome and its locking nut have been removed to allow fluid to exit through the passage as indicated by arrow 57. A coupling 30 is provided to allow a filter vent to be attached thereto to prevent concrete and other contaminants from escaping the formwork.

Figure 7 illustrates a conduit device including a body portion 40 through which an inlet passage 44 and an outlet passage 42 are defined. It will be appreciated by those skilled in the art that the body portion is not limited to two passages.

As described above, a hose 52 can be inserted into the inlet passage 44 to allow the formwork 11 to be filled with concrete, while the outlet passage 42 is provided with a coupling 30 as indicated by arrow 58 to allow a filter vent to be connected thereto to filter fluid exiting the formwork.

Figure 8 illustrates the body 40 of this conduit device from above, with the inlet passage 44 and outlet passage 42 side by side.

With reference to Figure 9 there is illustrated a filter vent for formwork, comprising a flexible hollow tubular structure 1 defining a channel therethrough. Attachment means are provided in screw coupling 2 which allows the filter vent to be

attached to the formwork, and tightened thereon via hexagonal bolt 3. The structure 1 contains filter media 5 such that when fluid flows through the structure, as indicated by arrow 4, particles are retained by the media 5, and the exiting fluid 6 is thus cleaner. To retain the filter media 5 within the structure 1 , an end fitting 7 may be provided. The end fitting could also be adapted to be a coupling, for receiving a hose for example.

Referring to Figure 10, the structure includes three types of filter media 8, 9, 10 in the form of granules or filter foam which have apertures therebetween for filtering matter passing therethrough in the direction of flow 4 along the channel. The first layer of granules or foam 8 has relatively large apertures for filtering coarse matter, the second layer 9 has smaller apertures for filtering finer matter, and the third layer 10 has yet smaller apertures for filtering yet finer matter.

Figure 1 1 illustrates the filter vent in use with fabric formwork, in which the tubular structure 12 is connected externally to the outside of a fabric formwork block 1 1 via the hose coupling. The hose coupling is screwed into a corresponding passage 13 of a conduit device in an outlet configuration.

With reference to Figure 12 there is illustrated a further embodiment of a filter vent in which the structure 15 is frustoconical, increasing in cross-section along the channel. The structure contains filter media held inside the channel by a grille 16.

Referring to Figure 13, it can be seen that the surface area of the filter media 20, 21 , 22 increases as the aperture size of the same decreases, as a greater amount of filter media of smaller aperture size 22 is located at the wider end of the structure 15.

With reference to Figure 14, there is illustrated a filter vent in cross-section, comprising a flexible hollow tubular structure 1 with a push-fit coupling 31 at the inlet end for connection to the corresponding coupling 32 on attachment means in the form of a hose coupling 30 which is provided with a thread 29 so that the hose coupling can be screwed into concrete formwork via the outlet of a conduit device.

In this example the tubular structure 1 defines a channel including three types of filter media 20, 21 , 22 in the form of foam or fabric layers which have pores or apertures for filtering matter passing therethrough in the direction of flow 4 along the channel. The first layer 20 has relatively large apertures for filtering coarse matter, the second layer 21 has smaller apertures for filtering finer matter, and the third layer 22 has yet smaller apertures for filtering yet finer matter.

In addition a further filter in the form of a bag-like structure 23 is attached by a clip 24 or any other suitable means to the tubular structure 1 , such that material exiting from the outlet of the tubular structure is then further filtered by the bag-like structure 23. The bag like structure 23 is a fabric layer with still yet smaller apertures than the third layer within the tubular structure, for filtering still yet finer matter.

As the apertures become smaller in size in successive layers of filter media, they become more susceptible to blockage by particles of a particular size. However, as the bag-like structure 23 has a comparatively high surface exposed to the flow of matter compared to the layers within the tubular structure, the susceptibility to blockage of the apertures thereof is reduced.

Figure 15 illustrates the filter vent in use with fabric formwork, in which the tubular structure 1 is connected externally to the

outside of a fabric formwork block 11 via the hose coupling. The hose coupling is screwed into a corresponding passage 13 of a conduit device in an outlet configuration.

Thus as wet concrete is pumped into the fabric formwork block 1 1 , air and water escapes via the outlet passage 13 and into the filter vent. The water from the block typically mixes with the concrete during this process and is thus contaminated with cement and other undesirable materials. Free water may be liberated from the concrete during filling. However, the filter vent reduces the amount of contaminants such that the air and water exiting the bag-like structure, as indicated by arrow 14, is at least partially purified.

Thus the invention is particularly useful in impermeable formwork solutions, where the creation of a contained formwork system is desired, especially when a means of filtration is incorporated. In this environment, entry and exit of all matter into or out of the formwork is controlled, helping to safeguard against leakage. The addition of filtration to the outlet also improves containment and reduces any possible external contamination.

It will be appreciated by persons skilled in the art that the present invention may also include further additional modifications made to the device which does not affect the overall functioning of the device.