WO2018202842A1

WO2018202842A1 - Apparatus and method for creating building structures

Info

Publication number: WO2018202842A1
Application number: PCT/EP2018/061482
Authority: WO
Inventors: Arto Koivuharju
Original assignee: Arto Koivuharju
Priority date: 2017-05-04
Filing date: 2018-05-04
Publication date: 2018-11-08
Also published as: GB2564083A; GB201707137D0

Abstract

A method and apparatus for constructing a multi-layered building structure. The method and apparatus comprising extruding a pair of opposing flows of a wet aggregate containing mixture to define a pair of outer layers and an optional void therebetween and simultaneously optionally injecting a foam material into the void before the wet aggregate containing material has dried.

Description

APPARATUS AND METHOD FOR CREATING BUILDING STRUCTURES BACKGROUND

The present invention is concerned particularly, but not exclusively, with an apparatus and method for creating structures for buildings. Buildings, such as houses, offices, hospitals and business building are generally formed by assembling a plurality of sub-components together. These may include, for example, bricks, blocks, steels, panels and so forth.

The sub-components are effectively laid out in the desired shape and connected together with an appropriate medium. This could be by welding or using cement or the like. Thus, the desired shape and layout of building can be created using the plurality of sub-components. In conventional construction the sub-components are brought together and assembled using manual labour using scaffolding, cranes or other raised platforms to allow the building staff to construct the desired building.

This is how buildings have been constructed for many years.

In more recent times pre-fabricated building have become available in which components of a building are built or formed in a factory (or off the build site) and then transported to the build site where they can be assembled. This dramatically decreased the build time for many buildings and reduced the complexity of construction at the build site.

Another way to build components of structures, more commonly used in industrial construction, is to use shuttering to create shapes or moulds which can receive an aggregate such as concrete. Concrete can then be poured into the 'mould' and once the concrete has set the shuttering can be removed. This process is used to build walls for example.

These existing techniques have successfully allowed a vast variety of buildings to be designed and built over many years.

However, the present inventors have established an unconventional approach to building construction which allows freedom of design but also allows for the use of local material in construction. The invention also advantageously allows the construction of building sub-components to be automated on-site at substantially reduced construction times than conventional systems with reduced man-hours in labour and improved safety. The arrangement furthermore allows more complex designs to be realised in an automated way.

The invention addresses many problems with conventional construction techniques and provides still further advantages.

SU BSTITUTE SH EET (RU LE 26) SUMMARY

Aspects of the invention are defined in the accompanying claims.

Viewed from a first aspect there is provided a method of constructing a multi-layered building structure, said method comprising the steps of: extruding a pair of opposing flows of a wet aggregate containing mixture to define a pair of outer layers and a void therebetween and optionally simultaneously injecting a foam material into the void before the wet aggregate containing material has dried.

Thus, a method described herein provides a method for the simultaneously forming two opposing sides of a multi-layered structure such as a wall. The two layers may be formed by extruding the material against a reinforcing mesh. The extruded material binds to the mesh. Because the material binds to the mesh on opposing sides a space or void is created therebetween. The width of the space or void is defined by the mesh used.

The term 'wet aggregate containing material' is intended to refer to the combination of cement and aggregates which are used in construction. The cement dries and hardens forming a solid structure encasing the aggregates. 'Wet' is intended to refer to a material that can be pumped i.e. it has some fluidity and can flow, such as cement.

The wet aggregate may be any suitable viscosity that can be pumped to the apparatus of the invention. Advantageously the viscosity may be between S1 and S5 or above. The skilled person will understand that te unit S is a standard viscosity unit for concrete, for example as set out in European Standard EN206-1 .

Viscosity may in fact change during the process as the material flows through the apparatus and hardens.

Extruding material in this way allows for a continuous flow of material onto the mesh. By moving the extruders (as discussed below) an elongate wall (having multi-layers) can be formed. Repeating layers on top of each other allows a long and tall multi-layered wall structure to be formed.

Optionally a foam material may additionally be introduced into the void. Specifically an expanding foam may advantageously fill the void creating a 3 layer structure. In effect a twin-walled structure in integrated insulation layer formed continuously and in a single pass. For example, the foam may be an expandable polyurethane foam such as are manufactured by BASF or DOW Chemicals. For example, a polyurethane mixture of isocyanate and polyol may be used.

Advantageously the inventors have established that by introducing foam simultaneously with the wet aggregate material the foam and wet surface of the aggregate form a bond.

Advantageously the pair of extruders may be arranged to move together along a predetermine path. Such a path may be predetermined according to a desired building or wall design. Movement of the extruders is discussed below.

Advantageously the optional foam by be simultaneously introduced to benefit from the bonding effect of the foam expanding against the wet i.e. as yet unhardened aggregate mixture. The extruders may not be physically opposing but may instead be provided with conduits that create two opposing flows of aggregate material. In one arrangement a single extruder could be used with a pair of conduits flowing therefrom.

Depending on the speed with which an accelerant hardens the aggregate mixture it may be possible for the aggregate to be mixed before reaching the end of the nozzle i.e. remote from the nozzle. In such an arrangement a conduit could be provided between a mixing apparatus and the nozzles i.e. the extruders may not be needed or needed proximate the wall or structure forming area. This may simplify the arrangement, for example a single mixing vessel could be used with an appropriate accelerant.

The or both extruders are controlled by a control arrangement that may allow the speed of each extruder to be controlled. This controls the flow rate of the material being extruded. This may for example be controlled so as to control the density of the aggregate i.e. the pressure applied to the aggregate. It may additionally or alternatively be controlled in response to the rate of movement (or feed rate) of the extruder relative to the wall or structure being constructed. The higher the feed rate, the higher the extruder speed. The opposing extruders may advantageously be independently operable to extrude or inject material at different speeds in accordance with control signals from the controller.

The apparatus may further be provided with an aggregate depth sensor as discussed above. That is a sensor arranged to determine the vertical height of the aggregate that has been extruded measure from a datum. The datum may for example be measured relative to the outlet of the extruder or forming surface (described below). A proximity sensor may also be used. Similarly the extruder speeds may be controlled in response to an indication of aggregate viscosity from a viscosity sensor. Viscosity may be determined by measuring the torque needed to turn a pump pumping the aggregate mixture and comparing that torque against a look up table or calculation to estimate or calculate viscosity. In order to reduce the hardening time of a cement/aggregate mix an accelerant may be used. Accordingly, an accelerant may be introduced into the extruders by means of an inlet port. Advantageously by introducing an accelerant into the aggregate in the extruder the accelerant can be thoroughly blended with the aggregate material provide a uniform hardening or the material. Addition of the accelerant may be controlled by the control arrangement with a suitable supply conduit, valve and pump arrangement.

The control of accelerant may be controlled in response to an indication of aggregate viscosity. For example a viscosity sensor may be used and its output communicated to the control arrangement. In order to form the shape of the wall or structure i.e. the surface, a forming surface may advantageously be provided which corresponds to the desired outer surface. For example for a flat wall a substantially flat surface may be used. For a cylinder (to build a column) a pair of opposing semi-circular forming surfaces may be used.

In each arrangement the extruders are arranged to output material through the forming surfaces. The forming surfaces may be coupled to the output of the extruder to form an integrated unit.

Advantageously, each extruder may comprise a forming surface having a leading end from which material is extruded and a trailing end, wherein portions of the trailing end are selectively movable towards and away from each other. In effect the leading end of the forming surface is rigid or fixed and the trailing end is movable. Specifically the trailing end may flex or bend in a plane perpendicular to the flat plane of the forming surface. Such an arrangement allows curves to be formed according to the invention maintaining the same twin outer wall and void therebetween.

A combination of moving the trailing edges or ends as the extruding arrangement moves forwards and by operating the trailing surfaces, complex building structures can be formed. The trailing edges may be moved by any suitable actuator means. For example linear actuators or motors may be coupled to the trailing surfaces and controlled by the control arrangement in accordance with a plan of the structure to be formed.

By moving the opposing trailing surfaces simultaneously in the same direction will maintain the uniform wall thickness around corners.

Advantageously the forming surfaces may be provided with a selectively protruding element that can extend from the forming surface into the wet aggregate material. In doing so an elongate indentation can be formed as the apparatus moves forwards. Such an indentation advantageously provides a 'key' to which plaster or render can adhere to provide a smooth surface in a secondary finishing process.

The protrusion may for example be an elongate portion arranged to extend through a hole in the forming surface and operated by a linear actuator. This may be controlled by the control arrangement according to a predetermined profile or programme.

The protrusion may be arranged to move only linearly i.e. only in and out of the forming surface. Alternatively or additionally the protrusion may be arranged to move up and down i.e. vertically. Thus, more complex 2 and 3 dimensional indentations can be formed. For example, a sinusoidal shape or zig-zag shape can be conveniently applied to the surface.

More than 1 protrusion may be incorporated into a forming surface.

In order to allow for repeated use of the apparatus and method a cleaning sequence may be used. To remove aggregate and accelerant from the extruders the extruders may be provided with a re-circulation path through which water may be cycled. Advantageously the outlet and inlet of the extruder may be selectively sealed and water or other cleaning fluid may be circulated until the cement/accelerant have been diluted. A portion of the cleaning water may be removed and replaced in each cycle to progressively clean the extruders. Thus, the extruders can be stopped without the concern of aggregate hardening inside.

Viewed from another aspect there is provided a forming apparatus for a wet aggregate mixture, said apparatus comprising a pair of extruders each having an extrusion outlet, the extrusion outlets being arranged to oppose each other, wherein the extruders are arranged in use to extrude a wet aggregate material to form two opposing outer layers and defining a void therebetween, the apparatus further comprising an injector arranged to communicate with the void and operable to release a foam material into the void. Advantageously the apparatus may be mounted onto a movable gantry which is able to move the apparatus in multiple axes. The gantry may be computer controlled in combination with the extruders and forming surfaces in accordance with a programme defining the structure to be formed or 'printed'. Thus complex structures can be formed including structures with curves.

The gantry arrangement may be provided with suitable conduits to supply electrical or hydraulic power as well as the mixture of aggregates and cement.

The gantry may be configured so that the extruders and associated apparatus can be rotated. Further complexity can be added to the structure. It will be recognised that the features described above with respect to the method aspect of an invention described herein may equally and advantageously be used in combination with the apparatus aspect in any suitable combination.

The forming surfaces may advantageously be selectively detachable from the extruder. Thus, different forming surfaces may be used. For example, the forming surfaces may be substantially flat with an optional flexible or movable trailing surface. Alternatively a semicircular forming surface may be used wherein an orifice is further provide for communication of wet aggregate from the extruder. In this embodiment an upper portion of the semi-circular forming surface may be a leading surface and a lower portion of the semi-circular forming surface a trailing surface. Viewed from yet another aspect there is provided a forming apparatus for a wet aggregate mixture, said apparatus comprising a pair of extruders each having an extrusion outlet, the extrusion outlets being arranged to oppose each other, wherein the extruders are arranged in use to extrude a wet aggregate material to form two opposing outer layers, each extruder further comprises a forming surface having a leading end from which material is extruded and a trailing end, wherein portions of the trailing end are selectively movable towards and away from each other.

The two opposing outer layers may be formed so as to define a void or space therebetween to receive reinforcing, insulation, a third material or a combination thereof. BRIEF DESCRIPTION OF THE DRAWINGS

The present teachings will now be described by way of example only with reference to the following figures in which like parts are depicted by like reference numerals:

Figure 1 shows an end view of the apparatus according to the invention and a gantry arrangement to allow for movement;

Figure 2 shows a single extruder;

Figure 3 show a cross-section through the extruder of figure 2;

Figure 4 shows a pair of opposing extruders and a shuttering arrangement;

Figure 5 shows a plan view of the arrangement of figure 4; Figures 6A and 6B show a plan view of the movable trailing surfaces of an extruder arrangement;

Figure 6C shows a plan view of one half of a curved wall formed with a movable trailing surface extruder;

Figures 7 A and 7B show additional views of an extruder with movable forming surfaces; Figure 8 shows a plan view of a circular structure formed using an extruder;

Figure 9A and 9B show an alternative forming structure for forming columns;

Figure 10 shows a further alternative forming surface for use with an extruder;

Figure 1 1 shows an apparatus according to a first embodiment for fabricating a construction element; Figure 12 shows an apparatus according to a first embodiment for fabricating a construction element;

Figure 13 shows an apparatus according to a first embodiment from the front for fabricating a construction element;

Figure 14 shows an apparatus according to a first embodiment from the front for fabricating a construction element; Figure 15 shows an apparatus according to a first embodiment from above for fabricating a construction element;

Figure 16 shows a side view of an apparatus according to a first embodiment;

Figure 1 7 shows an apparatus according to a second embodiment for constructing a building;

Figure 18 shows an apparatus according to a second embodiment for constructing a building having a changed construction direction ;

Figures 19A and 19B show an apparatus according to a second embodiment comprising nozzle groups in an extendable fork-like element; Figure 20 shows first and second nozzle groups in an extendable fork-like element;

Figure 21 shows first and second nozzle groups in a fork-like element in an apparatus according to first embodiment;

Figure 22 shows an apparatus according to a first embodiment from the front comprising nozzle groups in a fork-like element; Figures 23A and 23B show an example of application of staples to the material layer; and

Figure 24 shows an example of an apparatus constructing a frame of a building.

While the present teachings are susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that drawings and detailed description thereto are not intended to limit the scope to the particular form disclosed, but on the contrary, the scope is to cover all modifications, equivalents and alternatives falling within the scope defined by the appended claims.

As used in this specification, the words "comprises", "comprising", and similar words, are not to be interpreted in an exclusive or exhaustive sense. In other words, they are intended to mean "including, but not limited to". DETAILED DESCRIPTION

The present teaching relates to a method and apparatus for continuously forming a structure. Particularly, but not exclusively, the method and apparatus are concerned with a three dimensional printing technique which is capable of printing a laminar structure incorporating multiple layers.

The invention comprises a number of concepts which can be used in combination and which provide a synergy for forming a structure. These are described in detail below.

Figure 1 shows an end view of the apparatus 1 according to the invention. A gantry 2 is provided in the form of a frame which may be moved in a first direction by means of a pair of motors 3A, 3B in an x direction. An extruder 4A is shown which is mounted to an arm 5. The extruder 4A is mounted onto the arm such that the extruder can move vertically as shown by the arrows.

The arm 5 is rotatably mounted by a pivot 6 at the top of the gantry and the pivot arrangement 6 is arranged to be movable by a motor arrangement 7 in a second y direction. Gantries are used in many different applications. In the present application the gantry is arranged such that the extruder 4A is movable relative to the structure S_T in x, y and z directions and also rotatably by virtue of the pivot 6. Thus using a suitable controller to control the motors and pivot, the extruder can be aligned in any position relative to a structure to be formed. In Figure 1 a single extruder and arm are shown. However, as discussed below, advantageously a pair of opposing extruders may be mounted on the arm with novel forming surfaces.

Shuttering is intended to refer to surfaces or panels which are used to support wet aggregates such as cement during hardening. Figure 2 shows a single extruder 4A in more detail. Figure 3 shows a cross-section through the extruder 4A.

Referring to figure 2 the extruder comprises an inlet hopper 8 into which a wet aggregate or components thereof are introduced. These may include cement, water, additives, clay, other minerals or other composite components which enhance the wall properties. This may be introduced, for example, by a conduit mounted onto the gantry shown in figure 1 and connected to a reservoir of wet aggregate. The extruder comprises an outlet nozzle 9 which is generally tapered such that in use an extrusion of wet aggregate is ejected from the nozzle 9 of the extruder. The extruder comprises a drive motor 10 and gear/belt arrangement 1 1 to cause rotation of the internal components of the extruder (described below). The extruder may also comprise a pair of inlet washing ports 1 2 and a pair of outlet washing nozzles 1 3. These may be used to clean or rinse aggregate from the extruder after use. For example the nozzle 9 and hopper 8 may be closed and water passed into the extruder and out of the outlets 13. This acts to rinse out any aggregate or hardening accelerator which may be inside the body of the extruder. This prevents the extruder from becoming blocked or jammed with residual aggregate and/or accelerant.

Figure 3 shows a cross-section of the extruder shown in figure 2. The hopper 8 and nozzle 9 are shown together with the inlet and outlet ports 12, 1 3 and gear/belt housing 1 1 . Internally the extruder comprises an auger 14 which is in the form of a helical surface extending around and along a centrally located shaft 15. As the shaft is rotated (by the electric drive motor 10 and gear/belt arrangement 1 1 ) the helix or auger rotates directing any material between the 'blades' of the auger to be forced in the direction X shown by the arrow.

In use aggregate is introduced into the hopper 8 and is forced towards the nozzle 9 by the auger arrangement. It will be recognised that the auger is a mechanically simple and reliable arrangement. Depending on the pitch (i.e. the separation of adjacent blades of the auger) different aggregate materials can be extruded. A larger pitch allows for aggregates with larger stone or rock sizes to be extruded.

Figure 4 shows a pair of extruders 4A and 4B arranged to oppose each other i.e. the nozzles 9 are facing each other. Each extruder is substantially the same with each comprising a hopper and nozzle, drive means and so forth.

Figure 4 also shows a particular shuttering arrangement. Each extruder is provided with a forming surface 1 6. The forming surface is connected to the respective extruder and comprises a leading surface 17 and a trailing surface 1 8. The extruder moves (by means of the gantry shown in figure 1 ) in the direction shown by arrow A hence the reference to leading and trailing surfaces 1 7, 18.

The leading surface 17 of each forming surface 1 6 comprises an orifice 1 9 aligned with the nozzle of the extruder and arranged in use to allow extruded aggregate to pass from the extruder through the forming surface. The shuttering arrangement also comprises opposing forming surfaces 20 described in more detail below. In effect a movable channel is formed between the forming surfaces 16 and opposing surfaces 20 as the extruders move in the direction shown by arrow A.

Figure 4 also shows injectors 21 , 22 which are arranged to align with the space or void created between the opposing extruders. Two injectors are shown but only one may be used. Similarly, the central forming surfaces 20 may also be omitted. In use the injectors may advantageously inject a foam, such as an expanding foam (for example a polyurethane comprising polyol and isocyanate) into the space or void.

Figure 4 also shows optional depth sensors Si and S₂ which are arranged above each side of the apparatus and aligned with a respective side of the extruded structure. The two sensors may be, for example, proximity sensors which output an indication of proximity to the distal end of the sensor proximate to the space between the surfaces 16 and 20 where the aggregate is extruded. Thus, the sensors can indicate the height of the aggregate which has been extruded. This information can be communicated to the control arrangement and used in a feedback control to control the speed of movement and/or extrusion as discussed further below.

Each extruder may also be provided with an inlet port (one of the washing ports 1 2, 13 may be used) to introduce an accelerant into the extruder. This is described further below.

Figure 5 shows a plan view of the arrangement of figure 4 with the shuttering surfaces. The left hand extruder 4B is shown with aggregate 23 having been extruded as the extruders move in direction A.

As the extruders move foam F is injected by one or more injectors 21 , 22 into the void between the two extruded 'walls' shown at the trailing ends of the extruders in figure 5.

The opposing surfaces 20 and surfaces 1 7, 1 8 create the wall 24 shown leaving the trailing surface of the forming surface. By using an appropriate aggregate mixture and optional accelerant in combination with the speed with which the extruder moves in direction A the aggregate becomes sufficiently hard that it can support itself and not flow away once it leaves the trailing edges. The wall can then continue to harden.

Figures 6A and 6B show the movable forming surfaces. Figure 6A shows the forming surfaces 17, 1 8 in a straight configuration to create a straight wall or structural section as the extruders move in direction A shown in figure 5. In this arrangement the extruder further comprises a pivot 25 and associated drive means (for example an electric motor) which can cause the trailing surface 18 to be rotated. A linear actuator or other actuation means may equally be used.

Referring to figure 6B the electric motor 10 has been activated causing the trailing surface 18 to flex by virtue of an elongate arm rotating about the pivot. The trailing surface 1 8 is coupled or fixed to the extruder at its leading edge 17 but is flexible such that rotation of the arm causes the trailing part 28 of the trailing surface 18 to be deflected away from the normal straight line. As shown a curved trailing edge is thereby created.

Thus, in use the trailing surface can be selectively rotated changing the shape of the shuttering. In combination with the opposing extruder comprising a corresponding movable trailing surface a curved profile to a wall or structure can be provided. Specifically by moving two opposing trailing surfaces in the same direction as the extruders move along direction A shown in figure 5 allows a curved section of wall or structure to be conveniently formed by the moving extruders. Figure 6C shows half of a wall having a curved profile and formed by a movable trailing surface extruder as described herein. Figures 7A and 7B show additional views of an extruder with movable forming surfaces. Figure 7A shows the extruder in a straight path configuration and figure 7B shows the extruder in a curved path configuration. It will be recognised that adjusting the displacement d shown in figure 7B on opposing extruders allows differing and varying radii of curvature to be applied to a wall structure. The trailing surface may for example be formed of a flexible rubber or other flexible material.

In one example an extruder could move in a continuously curved path to form a circular structure. This is illustrated in figure 8 in plan view where a circular structure 29 has been formed.

Figure 9A and 9B show an alternative forming structure for forming columns. In figure 9A an alternative curved forming surface head is connected to the extruder nozzle. As discussed above the forming surfaces or head may be advantageously selectively removable from the extruder. In figures 9A and 9B a curved trailing surface is provided. This may extend as far as to form a semi-circle in one example.

In column forming the gantry described above is arranged to move the extruder or extruders only in a vertical direction as extrusion occurs from the nozzles. The extruders may though be rotated by the gantry as described above. Thus, curved of circular structures can thereby be formed. Figure 9B shows a plan view of the extruder and forming surface shown in figure 9A. The most distal parts of the forming surface 30 may be provided with a flexible region and actuator of the type described with reference to figure 6B for example allowing varying curved surfaces to be formed. Figure 10 shows a further optional feature of an invention described herein. In figure 1 0 a robotic arm 31 is attached to the extruder arrangement 4A on a trailing end of the arrangement i.e. the robotic arm is arranged to finish the surface 33 which has been formed by using a rotating polishing/sanding/grinding head 32.

It will be recognised that the gantry and extruder described herein may be conveniently configured to be a mobile structure, for example mountable on a lorry or truck trailer or the like. This advantageously allows the construction system to be completely mobile and used to form structures in a variety of locations. For example, in regions of natural disasters the apparatus could be used to rapidly rebuild accommodation or the like using locally available aggregate materials. Further arrangements incorporating the invention described above will now be described with reference to figures 1 1 to 24. A similar gantry system is shown together with reinforcing steels (or the like) around which the extruders can be controlled or 'driven'.

The nozzle groups 1 09 described below and shown in the figures 1 1 to 24 may advantageously be replaced with the extruders 4A and 4B described above and may additionally incorporate the movable forming surfaces described above, injectors and so forth.

It will be recognised that the arrangements described with reference to figures 1 to 10 may be advantageously used in any suitable combination of the arrangements described below with reference to figures 1 1 to 24. In the following, several embodiments of the invention will be described in the context of fabricating wall or construction elements or constructing a building. It is to be noted, however, that the invention is not limited to fabricating wall or construction elements or buildings. In fact, the different embodiments may have application e.g. in decoration of wall boards or wall elements, in fabrication of pillars or statues or barriers or sound barriers. In the following description, materials such as concrete, insulation material and reinforcement are given as examples. However, it is appreciated that instead of these materials, other materials can be used. For example, instead of concrete, any hardening material in a liquid form can be used, for example, plastic or mixture of stone materials or wood cellulose or wood-plastic composite or plaster or hempcrete or recycling materials. Also, the insulation material can be polyurethane, however, other materials, such as insulation wool, polystyrene or hay can be used instead. The reinforcement can be reinforcement bars, such as steel bar, or reinforcement net or wire or carbon fibre or nanomaterial products. The embodiments, according to an example, relate to a material printing apparatus, which may be used in automatic on-site fabrication. The apparatus extrudes, hardens, prints and connects materials which then create construction elements. The apparatus is configured to fabricate construction elements and/or buildings of combination of concrete and insulation material with reinforcements. In addition, the apparatus is able to laminate and spread different materials with coating means. The apparatus according to embodiments is configured to feed various construction materials around reinforcements during fabrication. Due to that, the fabricated element will become ready for house building. In addition, the fabricated elements and the constructed buildings meet the requirements of construction code also in countries having varying weather conditions. The embodiments of the invention are disclosed in more detailed manner next.

Figure 1 1 illustrates a first embodiment of an apparatus 1 00. The first embodiment of the apparatus is for fabricating a construction element. The element may be a wall element for a house or for any other building or for any other structure. In some cases, the element may be a floor element or a roof element. The apparatus 1 00 shown in Figure 1 1 constructs a construction element of layers of materials. In this example, the element is constructed from the ground upwards, however, the embodiments may be utilized when constructing an element sideways. In this embodiment, the apparatus 1 00 is connected to material containers (not shown in the figure) via material passing tubes 107 and 108. The apparatus comprises a frame 101 and a subframe 102. The subframe 102 consists of side poles 102A and a beam 1 05 being connected to the side poles 102A from its both ends. The side poles 1 02A of the subframe 102 are connected to the frame 101 , and the subframe 102 is configured to be moved relative to the frame 1 01 . The frame 1 01 comprises means to lift and lower the subframe 102 during manufacturing process as shown by an arrow B, thus acting as a crane for the subframe 102. Figure 1 1 shows an apparatus 100 wherein the subframe 1 02 is in its lower position, and Figure 12 shows an apparatus 1 00 wherein the subframe 102 is in its upper position. The apparatus of the first embodiment comprises also a production line 103. The production line 103 comprises rails 104 on both sides of the movable production line 103. The rails 104 are configured to move the frame 101 of the apparatus 100 during manufacturing to the direction of arrow A. The production line 103 is located on a bottom of the apparatus. The production line 103, according to an embodiment, comprises rollers that may be situated in the bottom in a matrix like manner or in some other formation. The rollers are utilized when moving the element under fabrication. Instead of rollers, any other conveying mechanism may be used, for example a conveyor belt.

The production line 103 further comprises fastening means for keeping the reinforcement in its position. The reinforcement may be in the form of a reinforcement net 106. Instead, also reinforcement bars or reinforcement wire may be used. In the example of Figure 1 1 , there is a pair of reinforcement nets 106. However, the amount of the reinforcement nets may vary depending on the thickness of the element. According to another embodiment, the production line 103 may be perforated, whereby the holes in the bottom may act as fastening means for the reinforcement. The reinforcement nets 106 can be placed in the middle of the production line 103 prior to manufacturing, whereby the frame 101 , the subframe 102 and a fork-like element (127, shown in Fig. 19A) of the beam 105 of the apparatus need to be able to pass the reinforcement during manufacturing process.

According to an embodiment, the production line has also means for fixing one or more of the following: heating components, plumbing components, air-conditioning components. These components are located on the production line so that the material will be extruded over them. Therefore, the components will already exist in the element/wall when the element/wall becomes ready, and there is no need to do embedding afterwards.

Figure 13 shows the apparatus according to the first embodiment from the front. The apparatus comprises nozzles for feeding various materials for the element under manufacture. The term "nozzles" in this description refers to nozzle groups comprising one or more nozzles for extruding material. A first nozzle group 1 10 for a first material is fixed to the beam 105 of the subframe 102. When the subframe 102 is being lifted or lowered, the first nozzle group 1 10 can be lifted or lowered respectively or nozzle group 1 10 can be lifted or lowered autonomously. The first material may be polyurethane or any other insulation material. According to another embodiment, the first material is any material. In addition to the first nozzle group 1 10, the apparatus 100 comprises at least one second nozzle group 109 for a second material. The second material may be a hardening material in liquid form, for example concrete, plastic or mixture of stone materials or wood cellulose or wood-plastic composite or plaster or hempcrete or recycling materials. The second nozzle group 109 may contain one or more nozzles. The second material for the second nozzle group 109 may be fed through an extruder 109A being attached to the subframe 102. An extruder 109A is a moving element being able to move 180 degrees or more horizontally and 180 degrees or more vertically depending on desired structure being built.

According to an embodiment of figure 13, there are two second nozzle groups 109 on both sides of the first nozzle group 1 10. Each of said two second nozzle groups comprises a corresponding extruder 109A. According to an embodiment, the two second nozzle groups

109 are configured to extrude the same material. According to another embodiment, the two second nozzle groups 109 are configured to extrude different materials. The second nozzle groups are also able to extrude the material horizontally. This means that the nozzles are able to create three-dimensional surface, e.g. different shapes extending from the element horizontally.

According to the embodiment shown in Figure 13, the material from the material container is passed via material passing tubes 107 and 108. The material containers (not shown in the figure) may be located next to the apparatus 100. The first and second nozzle groups are arranged in the apparatus in such a manner that they can operate substantially concurrently. This means that when an element or a building is being fabricated, material from each nozzle group is fed for the same layer.

During manufacturing, the material from the second nozzle groups 109 is extruded followed by the material from the first nozzle group 1 10. The material from the second nozzle groups 109 will take place around the reinforcement, and the material from the first nozzle group

1 10 is then extruded to the space between the materials from the second nozzle groups 109.

The first and second nozzle groups are arranged in the apparatus in such a manner that they can pass the reinforcement net or bars or other components, such as electric, heating, ventilation, air conditioning, or data communications components, during the operation. This means that the nozzle groups are arranged in the apparatus in parts. The middle part comprises the first nozzle group that is able to extrude the first material between the reinforcement nets. The second nozzle groups are located on both sides of the middle part, in such a manner that a reinforcement net or bar may get between the first nozzle group and the second nozzle group.

The apparatus according to a first embodiment may further comprise one or two rolls 1 15 for supporting steel wire. Said one or two rolls may be located on both sides of the element under manufacture in order to provide additional supporting steel structure to the element, if needed.

Figure 1 3 shows an apparatus 1 00 wherein the subframe 1 02 is in its lower position, and Figure 14 shows an apparatus 1 00 wherein the subframe 1 02 is in its upper position.

In addition to first and second material, also one or more other materials may be extruded to the element under manufacture.

As shown in Figure 1 5, the apparatus may contain one or more control arcs 1 1 1 that enable manufacturing of curved shapes. The control arcs 1 1 1 may be replaceable with control elements of different shapes. In this embodiment, the control arcs 1 1 1 are attached to the subframe on both sides of the apparatus and their shapes form a circle in the middle of the apparatus. Center point of the circle defines the curving point of the element.

The apparatus may also comprise one or more magazines or cases (shown in figure 1 1 with reference number 130) for storing hooks or staples, and one or more applicators for applying the staples to the element under manufacturing. An applicator may be attached on one side of the subframe. Similarly, a magazine may be attached to the subframe near the applicator. The applicator is configured to take a staple from the magazine, and place it to the element during the manufacturing process. The staple (i.e. hook) can have different shapes, for example a U-shape, an angular shape, and/or the staple may have hooks in the ends. Figures 23a and 23b show the installation of the staples. Figure 23a shows a part of a frame 101 , a part of a subframe 102 and a part of a production line 103. In the example of Figure 23a, the constructing process has been started by extruding a first layer 150 of materials around and between the reinforcement nets 1 06. A staple applicator 1 37 is configured to add a staple 1 39 on top of the first layer 150 of materials so that the legs of the staple 139 are inserted to the material layer. Figure 23b shows an example of a moment just before the staple is inserted to the material. As can be realized from the figure 23b, the staple extends over the reinforcement and thus acts as a transversal reinforcement for the element/wall being constructed.

Figure 17 shows a second embodiment of an apparatus 100. Apparatus 1 00 of Figure 1 7 is configured to construct a building. Instead of reinforcement nets, in Figure 1 7 the used reinforcement is in the form of reinforcement bars 120. It is appreciated that reinforcement nets can be used instead. The reinforcement bars 1 20 are fixed to the production line 103 in pairs, so that in the complete wall/element they will exist within the hardening material on both sides of the wall. In the second embodiment of the apparatus, the production line 103 is removable from the apparatus, i.e. from the rails 104. This means that when a building is ready, the apparatus is moved from the construction place, and the production line 1 03 is left under the building. Therefore, the production line may be utilized as a basis for a floor of the building.

In the apparatus of Figure 17, the first and second nozzle groups are attached to a fork-like element 1 27. The fork-like element 127 is fixed to a connecting element 125 that is movably fixed to the beam 1 05 of the subframe 102. The fork-like element 1 25 according to an embodiment comprises three prongs, to ends of which a nozzle group is fixed. The first nozzle group is located in the middle prong, whereas the second nozzle groups are located in the outermost prongs. Therefore, the first nozzle group is able to extrude the first material between the pair of reinforcement bars 120, and the second nozzle groups are able to extrude the second material over the reinforcement bars, on both sides of the first material. The prongs of the fork-like element 127 can be extended and shortened as shown with an arrow D so that in the beginning of the manufacturing process the prongs of the fork-like element 127 are extended to reach the production line 103 for extruding the first material layers. During the construction, the prongs are shortened according to the amount of the material layers. In addition, the fork-like element 127 may be rotated 360 degrees, e.g. when a pillar is being constructed. In such a case, a reinforcement bars may be in an upright position, around which a pillar is being fabricated.

The connecting element 1 25 is able to travel along the beam 105 of the subframe 102 (direction C) and is able to change the extrusion direction of the first and second nozzle groups as shown in Figure 18. In the example of Fig. 1 8, this is done by turning the fork-like element and nozzle groups 90 degrees by the connecting element 125. Due to such operation, the apparatus can extrude material to direction A and to direction C.

Figure 1 9a shows the fork-like element 127 with nozzle groups in its upper position, i.e. having short prongs. Figure 19b shows the fork-like element 1 27 with nozzle groups in its lower position, i.e. having extended prongs. It is appreciated that the extension/shortening is also used when the apparatus is constructing towards the direction C (shown in Figure 18). Figure 20 shows a close-up of the first 1 10 and second 109 nozzle groups of the apparatus when attached to the prongs 140 of the fork-like element. It is realized from Figure 1 9 that a space is formed between the first nozzle group 1 10 and the second nozzle groups 1 09. This space is reserved for the reinforcement so that the apparatus is able to pass reinforcement bars/net or any other component or element extending from the production line.

Figure 20 shows also a magazine 1 30 for storing hooks or staples. As mentioned, the apparatus comprises an applicator for applying the staples to the element under manufacturing (see Figures 23a, 23b).

The apparatus 1 00 may further comprise guiders 1 1 7. The guiders 1 17 according to an embodiment may be disc-shaped pieces that are configured to control the shape of the hardening material during the manufacturing process. When the hardening material is being extruded over the reinforcement, the guiders 1 17 are configured to smooth out the surface of the element. The guiders 1 1 7 may be located next to the second nozzle group so that they are able to pass the outer walls of the element under fabrication. The guiders 1 17 may have a height corresponding to the height of one material layer. According to an embodiment, guiders with different heights may be used as well.

Figure 21 shows a first embodiment of an apparatus comprising a nozzle configuration of the second embodiment. It is thus appreciated that in the apparatus, the nozzle groups may be arranged to the apparatus of the first embodiment (shown in Figure 20 or in Figure 10) in a fork-like element 127. The difference is that in the example of figure 1 1 , the second nozzle groups are further supported by the side poles of the subframe, whereas in the example of figure 20, the second nozzle groups are situated in the fork-like element 127 with the first nozzle group and being connected to the beam 105 of the subframe by a connection element 125. Figure 22 shows an apparatus of Figure 21 from the front.

The apparatus according to the first and the second embodiment is configured to fabricate the element or the building fabricated with material layers. Figure 24 illustrates an example of constructing a frame of a building 200 with an apparatus according to the second embodiment. It is appreciated that the height of the construction will increase layer by layer during operation of the apparatus. Each construction layer comprises hardening material (e.g. concrete, wood cellulose) and insulation material (e.g. polyurethane). In addition, the element/wall of the building comprises a reinforcement (e.g. net of steel wires, reinforcement bars, fiberglass cord, carbon fiber, plastic composite). The hardening material is extruded around the reinforcement in layers, so that the reinforcement will become fully covered with the hardening material. The insulation material is extruded in layers between the opposite sides of the wall element, i.e. between the hardening materials. The complete element or the complete building thus comprises at least hardening material with reinforcement on both sides of the element/wall and insulating material between hardening material.

According to an embodiment, the apparatus according to the first or the second embodiment may further comprise coating means. There may be coating means on the both sides of the apparatus so that they are able to perform coating for both sides of the wall element. The coating means may also be located only on one side of the apparatus. According to an embodiment, the coating means are located right after the second nozzle group, so that they are able to perform coating of the same layer of hardening material that has been just extruded. According to an embodiment, the coating means are located below the second nozzle groups, so that they are able to perform coating of the previous material layer.

According to an embodiment, the coating means are configured to produce a final surface to the element at the same time when the element is being fabricated. The coating means may comprise one or more different coating components. There can be a coating component for paintwork, for plaster, for grout, for laminate, for direct write technology, for wirings, for smart film, for touch sensitive coating. The coating means can also provide solar cell coating for the element from the corresponding coating component. In above, the apparatus for manufacturing a construction element or constructing a building has been disclosed. It has been discussed, that the used material comprises a hardening material and an insulation material. It is appreciated that the material being used can deviate from the previous example. According to an embodiment, only concrete/cellulose layer with reinforcement may be enough. According to an embodiment, the insulation layer can be composed on more than one insulation materials. According to an embodiment, the reinforcement is not needed, if the hardening material is composed of the hardening material and the reinforcing material. In that case each material layer comprises the hardening material and the insulation. Yet further, according to an embodiment, the order and/or amount of the materials at each layer may be different. For example, there may be additional layer of concrete within the insulation material, or there may be additional wirings.

The operations of the apparatus according to embodiments are controllable by a control software being stored on a memory of a control device. The control device further comprises a processor that is configured to process the computer instructions of the control software, and cause the control device to transmit control commands to the apparatus. The control commands are configured to control the material extrusion from the nozzle groups, the movement of the frame, the movement of the subframe, the movement and the rotation of the fork-like element, staple application, coating etc. The control device further comprises input/output circuit for enabling communication between the control device and a user. The control device may contain a display configured to display at least the status of the apparatus, and a user interface for enabling input from a user. The user interface may be in the form of graphical user interface, and/or the user interface may contain physical or virtual input buttons. The user interface may - in addition or instead - comprise a voice recognition system to receive voice commands from the user.

It is apparent that the present invention is not limited solely to the above-presented embodiments, but it can be modified within the spirit and scope of the appended clauses and claims.

Further aspects of inventions are set out in the following numbered clauses:

1 . An apparatus for constructing comprising at least three nozzle groups (109, 1 10) for extruding construction materials in layers, so that a construction layer comprises materials from each nozzle group, characterized in that the nozzle groups (109, 1 10) are arranged in a subframe (1 02) of the apparatus separate from each other in such a manner that a first nozzle group (1 10) of the three nozzle groups is configured to extrude a first material and the second and the third nozzle groups (109) are configured to extrude at least a second material around a reinforcement (1 06) on both sides of the first material.

2. The apparatus according to clause 1 , wherein each of the three nozzle groups (109, 1 1 0) is arranged in a respective prong (140) of a fork-like element (127).

3. The apparatus according to clause 2, wherein the prongs (140) of the fork-like element (127) are extendable.

4. The apparatus according to any of the clauses 1 to 3, wherein the subframe (1 02) is attached to a frame (101 ) of the apparatus, wherein the frame (101 ) comprises means for lifting and lowering the subframe (1 02).

5. The apparatus according to clause 4, further comprising rails (1 04), wherein the frame (1 01 ) of the apparatus is configured to be moved along the rails (1 04).

6. The apparatus according to clause 2, wherein the subframe (1 02) comprises a beam (1 05), into which the fork-like element (127) is movable attached. 7. The apparatus according to any of the clauses 1 to 6, further comprising a production line (1 03) having means for fixing the reinforcement (1 06).

8. The apparatus according to clauses 1 to 7, further comprising a production line (103) having means for fixing one or more of the following: heating components, plumbing components, air-conditioning components. 9. The apparatus according to clause 7 or 8, wherein the production line (103) is located between the rails (1 04).

10. The apparatus according to any of the clause 1 to 9, further comprising an applicator (1 37) for applying staples (1 39) transversally on material layers. 1 1 . The apparatus according to any of the clause 1 to 10, wherein the three nozzle groups (109, 1 10) are configured to operate substantially concurrently.

12. The apparatus according to any of the clause 1 to 1 1 , further comprising a control device having at least one processor, an input/output circuit and a memory including computer program code, the memory and the computer program code configured to, with the at least one processor, cause the control device to control operations of the apparatus.

Claims

1 . A method of constructing a multi-layered building structure, said method comprising the steps of: extruding a pair of opposing flows of a wet aggregate containing mixture to define a pair of outer layers and a void therebetween, and simultaneously injecting a foam material into the void before the wet aggregate containing material has dried.

2. A method as claimed in claim 1 , wherein the wet aggregate containing material is a mixture of cement and aggregates

3. A method as claimed in claim 1 or 2, wherein the foam material is an expandable insulating foam material.

4. A method as claimed in claim 3, wherein the foam material is a polyurethane foam.

5. A method as claimed in any preceding claim, wherein the wet aggregate containing mixture has a flexibility of between S1 and S5 according to European Standard EN206.

6. A method as claimed in any preceding claim, wherein the pair of extruders are arranged to move together along a predetermine path; the pair of extruders have a predetermined separation defining the void; and an injector simultaneously moves with the pair of extruders and is operated to introduce an expandable foam into the void.

7. A method as claimed in claim 6 wherein the extruders are independently operable to extrude or inject material at different speeds.

8. A method as claimed in claim 7, wherein the extruder speeds are controlled in response to a depth indication of the wet aggregate containing mixture.

9. A method as claimed in any of claims 6 to 8, wherein the extruder speeds are controlled in response to an indication of aggregate viscosity.

10. A method as claimed in any preceding claim, wherein an accelerant is simultaneously added to the wet aggregate containing mixture during the extrusion step.

1 1 . A method as claims claim 10, wherein an accelerant is added in response to an indication of aggregate viscosity.

12. A method as claimed in claim 10 or 1 1 , wherein the accelerant is added at or proximate to an outlet of an extruder.

13. A method as claimed in any preceding claim wherein each extruder comprise a forming surface having a leading end from which material is extruded and a trailing edge, wherein portions of the trailing edges are selectively movable towards and away from each other, the method comprising the step of moving the trailing edges simultaneously as the extruders move.

14. A method as claimed in claim 13, wherein the trailing edges are selectively moved in the same direction.

15. A method as claimed in claim 13 or 14, wherein the forming surfaces further comprise at least one protruding portion operable to protrude from the forming surface into the wet aggregate containing mixture, the method further comprising the step of causing the protrusion to protrude into the wet aggregate containing mixture during movement of the forming surface to create an indentation in the wet aggregate containing mixture.

16. A method as claimed in claim 15, wherein the at least one protruding portion is movable in a direction perpendicular to the plane of the forming surface away from the forming surface and is further movable in a vertical plane, the method comprising the step of causing the protrusion portion to protrude into the wet aggregate containing mixture and causing the protrusion portion to oscillate vertically as the forming surface moves.

17. A method as claimed in claim 16, wherein a sinusoidal or zig-zag indentation is formed in the wet aggregate containing mixture.

18. A method as claimed in any preceding claim wherein the extruders are selectively operable to receive a flow of water and to re-circulate the water to clean the extruder.

19. A forming apparatus for a wet aggregate mixture, said apparatus comprising a pair of extruders each having an extrusion outlet, the extrusion outlets being arranged to oppose each other, wherein the extruders are arranged in use to extrude a wet aggregate material to form two opposing outer layers and defining a void therebetween, the apparatus further comprising an injector arranged to communicate with the void and operable to release a foam material into the void.

20. An apparatus as claimed in claim 19, further comprising a moving gantry arranged in use to simultaneously move the pair of extruders and the injector along a predetermined path.

21 . An apparatus as claimed in claim 20, wherein the gantry is arranged to simultaneously move the extruders and injector in x, y and z directions.

22. An apparatus as claimed in claim 20 or 21 , wherein the gantry is arranged to rotate the extruders and injector.

23. An apparatus as claimed in any of claims 18 to 22, wherein the extruders are independently operable through a control arrangement to extrude or inject material at different speeds.

24. An apparatus as claimed in any of claims 18 to 23, wherein each extruder further comprises an aggregate depth indicator indicating the depth of aggregate measured from a datum, and wherein the extruder speeds are controlled in response to a depth indication from said indicator.

25. An apparatus as claimed in any of claims 18 to 24, further comprising a viscosity sensor arrange to determine the viscosity of wet aggregate being supplied to the extruders, and wherein the extruder speeds are controlled in response to an indication of aggregate viscosity.

26. An apparatus as claimed in any of claims 18 to 25, wherein each extruder further comprises an accelerant inlet port arranged in use to receive a hardening accelerator and to introduce the accelerant into the extruded flow of wet aggregate.

27. An apparatus as claimed in claim 26, wherein a control arrangement is configured to receive a viscosity indication and to control the accelerant inlet port in response to the viscosity indication and a predetermined viscosity threshold.

28. An apparatus as claimed in any of claims 18 to 27, wherein each extruder comprises a forming surface having a leading end from which material is extruded and a trailing end, wherein portions of the trailing end are selectively movable towards and away from each other.

29. An apparatus as claimed in claim 28, wherein the forming surfaces are substantially flat surfaces comprising an orifice adjacent to an extruder outlet at a leading end of the surface and an elongate trailing surface extending from the leading end, wherein the trailing surface is flexible in a direction perpendicular to the plane of the substantially flat surface.

30. An apparatus as claimed in claim 29, further comprising an actuator at a trailing end of each surface and operable to move a distal end of the trailing end.

31 . An apparatus as claimed in claim 30, wherein a control arrangement is adapted to cause the trailing edges to move simultaneously in the same directions.

32. An apparatus as claimed in any of claims 28 to 31 , wherein the forming surfaces further comprise at least one protruding portion operable to selectively protrude in use from the forming surface into the wet aggregate mixture.

33. An apparatus as claimed in claim 32, wherein at least one protruding portion is movable in a direction perpendicular to the plane of the forming surface and is further movable in a vertical plane.

34. An apparatus as claimed in any of claims 28 to 33, wherein the forming surface is selectively detachable from the extruder.

35. An apparatus as claimed in claim 18 to 27, wherein each extruder comprises a semicircular forming surface and wherein an orifice is further provide for communication of wet aggregate from the extruder.

36. An apparatus as claimed in claim 35, wherein an upper portion of the semi-circular forming surface is a leading surface and a lower portion of the semi-circular forming surface is a trailing surface.

37. An apparatus as claimed in claim 36, wherein the orifice is centrally located within respect to the leading and trailing surfaces.