[0001] The present invention relates to moulds for a building module and methods of using and lifting them according to the preambles of the appended independent claims. Especially preferably the mould for the building module and the method of using and lifting the internal mould portion thereof are suitable for manufacturing a building module used in construction industry by casting them from concrete. In this context the term building module generally means a construction unit which at its simplest comprises two corners and that usually is rectangular in shape. Another extremity could be a circular or elliptical unit or another unit with round and/or polygonal shapes. Production of elevator shaft modules, room modules or other corresponding modules having a square or rectangular cross-section may be mentioned as an advantageous embodiment of the invention.

[0002] The problem in the production of above-mentioned building modules by casting of concrete is the separation of the mould and the cast module from each other after the module has set. Without special actions the cast module and the mould remain attached to each other. A simple and traditional solution is to completely dismantle the mould away from the module, even though it is reasonable only in production of single pieces. [0003] Prior art discloses a number of solutions applicable to serial production, whereby the moulds may be reused many times. For example, EP-B1-0 880 432 discloses a solution in which the mould blocks are made of a heat-expanding material. Thereby the external portion of the mould is kept cold during casting and the internal portion of the mould is kept hot. When the casting has set, the external portion of the mould is heated, whereby it expands so that it may be lifted away from the casting. The internal portion of the mould of the casting is either cooled or it is allowed to cool from the heated state so that it shrinks sufficiently to be lifted away from inside the casting. It is, of course, possible to lift the actual casting away from between the mould blocks. Such a solution is not, however, reasonable as far as energy economy is concerned, because both the heating and cooling of mould portions use energy mainly unnecessarily. Additionally different connections are needed for at least either electricity or heat transfer medium, whereby the moving of mould portions becomes essentially more difficult.

[0004] Prior art also discloses a number of mechanical solutions wherein the mould parts are made of a number of pieces which are then moved in relation to each other. US patent document 4300746 describes a mould solution in which the external mould portion forming the circumference is divided into two pieces from its opposite corners, whereby removing the fasteners located in the corners allows the mould pieces to move sufficiently farther away from the casting. The internal mould portion consists of four pieces so that the pieces forming the two opposing comers are wedge- like so that they may be lifted away from their places when the casting has set, subsequent to which the other mould pieces may move farther away from the casting.

[0005] US-A-5524861 , on the other hand, describes the external mould portion as being formed by a number of wall pieces hinged by their lower edges so that the wall pieces may be lifted to a vertical position and naturally opened (lowered) by means of hydraulic cylinders. The internal mould portion consists of straight wall pieces and corner pieces. The comer pieces may be pushed along the beveledbeveled end surfaces of the wall pieces by means of e.g. hydraulic cylinders in the same level with the wall pieces and pulled inside so that the wall pieces may be moved away from the casting. [0006] The solutions described in the two latter documents, on the other hand, require the use of hydraulic or some other type moving apparatuses, which increase the mould costs essentially and in practice make it impossible to relocate the mould portions.

[0007] Thus, one of the problems to be solved by means of the invention is providing a clearance between the mould and the casting so that the internal and external mould portions may both be moved to a new casting station in one piece. This method is advantageous because the mould portions may be moved to a new casting station already when the actual casting has not yet set sufficiently for moving. This method allows a considerable increase in the production speed. However, an advantage is also that the actual casting may be removed from the casting station between the mould portions without the need to disassemble the mould. The above- mentioned clearance allowing the mutual movement of the mould portions and the casting, should however, be possible to arrange without complex structural solutions or without the use of special mechanisms, such as hydraulic mechanisms, arranged in connection with the mould portions.

[0008] Thus the purpose of the invention is to improve the state of the art by describing a mould solution that is advantageous in comparison with existing solutions and methods as well as both a method of using a mould for a building module and a method of lifting the internal mould portion.

[0009] One of the objects of the invention is to provide such a mould and a method of using a mould for a building module wherein the mould may be easily produced and either the whole mould portions or the whole building module may easily be removed from the casting station.

[0010] Another object of the invention is to provide such a mould and method for using a mould for a building module allowing forming the needed movement clearance between the mould and the casting without disassembling the mould.

[0011] ^" A third object of the invention is to provide such a mould and a method of lifting the internal mould portion of the mould for a building module wherein the mould may be easily produced and either the mould or the building module may easily be removed from the casting station.

[0012] The above-mentioned objects and other objects of the invention are mainly achieved as disclosed in the appended independent claims. [0013] Other characteristic features of the invention will become apparent from the description of some advantageous embodiments in the appended dependent claims, the following description of the invention and the appended figures.

[0014] At least some of the following advantages may be achieved by using even the simplest of the embodiments of the invention: · Easy and simple design of mould blocks,

• Simple and easy to open locking of mould blocks to each other,

• The mating surfaces of adjacent mould blocks stay against each other also when the mould is opened, • The mould blocks stay in a vertical position also when they allow removal of the casting from between the blocks or when lifting the blocks from around the casting,

• When the locking between the mould blocks is opened, the mould blocks move away from the casting, and

• The mould may be quickly closed to a casting position, allowing a considerable increase of productivity. For example, when working in two shifts it is possible to increase productivity by 50 % by casting at least three castings with the same mould instead of the previous two castings or at least by 33 % by casting four castings instead of the previous three castings.

[0015] In the following the mould for a building module, its method of use and the lifting method of its internal mould portion are described in more detail by way of reference to the appended drawings, in which

Figure 1 illustrates a building module and a mould for the building module according to the present invention used in the production thereof in assembled state seen from above,

Figure 2 illustrates the upper portion of the mould for a building module of figure 1 seen from the direction A - A ,

Figure 3 illustrates the external mould portion of the mould for the building module according to an advantageous embodiment of the present invention,

Figure 4 illustrates the other mould block of the external mould portion of the mould for the building module according to an advantageous embodiment of the present invention,

Figure 5 illustrates connecting the mould blocks of the external mould portion of the mould for a building module according to an advantageous embodiment of the present invention seen from the direction B - B of figure 3,

Figures 6a and 6b show two design alternatives of a wedge bar used in the connection of the mould blocks according to an advantageous embodiment of present the invention, Figure 7 illustrates an alternative wedge bar design according to another advantageous embodiment of the present invention,

Figures 8a and 8b illustrate in more detail the connection point between the mould blocks of the external mould portion and the operation of the wedge bar in its different positions,

Figure 9 illustrates the mould blocks of the internal mould portion according to an advantageous embodiment of the invention assembled in casting station,

Figure 10 illustrates in more detail the connection point between two parallel mould blocks of the internal mould portion according to figure 9, Figure 11 illustrates a mould for a building module according to another advantageous embodiment of the present invention seen from above,

Figure 12 illustrates a partially sectioned enlargement of the upper right corner of the mould for the building module according to another advantageous embodiment of the present invention shown in figure 10 in casting station, Figure 13 illustrates a partially sectioned enlargement of the upper right corner of the mould for a building module according to another advantageous embodiment of the present invention shown in figure 10 in opened position,

Figure 14 illustrates a partially sectioned enlargement of the upper right corner of the internal mould portion of an additional embodiment according to the present invention, and

Figure 15 illustrates the internal mould portion according to figure 9 as a sectional side view.

[0016] Figure 1 illustrates a mould for a building module according to the invention with a casting 10 cast inside it, which may also be called a building module. In the embodiment shown here the building module forms an essentially closed ring structure, but the invention may also be applied to production of a module having only two corners, i.e. in practice it could be the production of a U-shaped module having three wall portions. The ring structure may consist of, as a starting point, an essentially closed triangular building module, up to a circular building module. The mould used in the production of the building modules of this type mainly consists of two parts - the external mould portion 20 and the internal mould portion 60.

[0017] As shown in figures 1 to 4 the external mould portion 20 consists in this embodiment of the invention of two external mould blocks 20.1 and 20.2. The external mould blocks 20.1 and 20.2, on their behalf, comprise actual mould surfaces or plates 22 that are supported to external stiffeners 24, which in this embodiment have been arranged as shown in figure 2 to essentially horizontal levels outside the mould plates 22 with essentially constant intervals (of the order of 300 to 600 mm) along the whole height of the mould. Another alternative is to arrange the intervals between the stiffeners according to the mould pressure, i.e. increasing in frequency going downward in the mould. Brackets 26 have been arranged to the ends of the stiffeners 24, each of which brackets may be an integral part of the stiffener or a separate part attached thereto with the mould blocks 20.1 and 20.2 being fastened to each other by means of a wedge bar 40 (shown in more detail in figures 5, 6a and 6b) pushed through the holes 28 in the brackets. Additionally, in the embodiment shown in figures 1 to 4 the opening between the mould blocks 20.1 and 20.2 is sealed by means of a resilient member 30. The stiffeners 24 may be formed, as schematically shown in figure 2, of flat iron bars, but in view of rigidity a better solution would, of course, be the use of an I- profile or some other profile. The flat iron bars 24 shown as stiffeners in figure 2 are shown as being positioned on different heights in different mould blocks 20.1 and 20.2, i.e. staggered so that the brackets 26 arranged at the ends thereof are suitably located one on top of the other. Another possibility is to arrange the stiffeners on the same height and to arrange a bracket made of e.g. flat bar to the other side surface of the other stiffener. Thus the bracket and the stiffener of the adjacent mould block are suitably located one on top of the other. The brackets may be fastened either to the ends of the stiffeners, on the outer edge of the stiffeners (shown in figures) or on the side of the stiffeners (such as the web of the I-beam.

[0018] Figures 3 and 4 illustrate the external mould portion in more detail. In the illustrated embodiment the mould blocks 20.1 and 20.2 are in principle similar. The only difference is the above-mentioned staggered arrangement of stiffeners 24. In case the stiffeners are, e.g. the l-profiles mentioned earlier, they may also be aligned with each other, i.e. on the same height in both mould blocks, whereby only the brackets are fastened to the stiffeners so that they are located in a staggered way when fastening the blocks to each other. The mould block 20.1 and thus also the block 20.2 are in this embodiment formed by a series of stiffeners 24 with mould plates 22 attached to them arranged in an angle required by the casting (90 degrees shown in this example). When the external mould portion 20 is assembled from two mould blocks 20.1 and 20.2, the mating surfaces of the mould plates 22 may be positioned directly against each other, i.e. in case the vertical end surfaces of the mould plates 22 are cut at right angles, the end surface of one mould plate may be located directly against the side surface of the other plate, and if the end surfaces are beveledbeveled at suitable angle, preferably in an angle of 45 degrees with a right-angled mould, the end surfaces may be located directly against each other. In the embodiment shown in the figures the end surface of the mould plate 22 of the mould block 20.1 is, however, provided with, preferable by fastening thereto, a resilient sealing member 30, a resilient/compressible batten, preferably made of rubber, plastic or the like applicable material, which is pressed against the mating surface of the mould plate 22 of the opposite mould block 20.2 during assembly of the mould, the mating surface being the internal side surface of the end of the mould plate 22 of the adjacent mould block 20.2 as shown in the figures.

[0019] The external mould portion may also consist of, in addition to the above- mentioned mould portions comprising a corner, straight mould blocks. In this case, at the latest, the bottom plate of the mould is preferably, but not necessarily, provided with guides for mould blocks by means of which the desired form for the building module is produced. In this case, for the assembly of a rectangular, more widely a quadrilateral, mould four external mould blocks are needed, one for each wall of the building module. Compared with a mould block having a corner this alternative has the advantage that by arranging two more mould blocks it is possible to form a building module of another size. In other words, supposing that, for example, the first four mould blocks may be used for producing a building module having a square cross-section, an elongated rectangular building module may be produced by replacing the two opposing mould blocks with longer mould blocks. It should be understood that the present invention is also suitable for production of building modules having curved surfaces. In such a case one or more of the mould blocks is curved. Thus it is also possible to produce round, i.e. cylindrical building modules, in which case the number of the blocks of the external mould portion is at least two, preferably at least three. In practice, in the solution according to the invention the number of the mould blocks of the external mould may vary from two up to the number of the corners (or sides) of the building module, although it is in principle possible to assemble one or more of the sides of the mould from a number of mould blocks.

[0020] Figure 5 shows the connection of two external mould blocks to each other, even though a principally similar attachment method is in use for connecting the mould blocks of the internal mould portion, as is described later. The example used here is the external mould portion 20.1 shown in figure 3, the mould portion being seen in figure 5 from the direction B - B. The figure shows mould plates 22, stiffeners 24 supporting them as well as brackets 26 arranged/fastened to the stiffeners 24. The external mould blocks are connected to each other so that as the mould blocks are standing on a base the mould blocks are placed next to each other so that the brackets 26 of the adjacent mould blocks are situated one on top of the other, whereby a wedge bar or locking bar 40 may be pushed through the holes 28 in the brackets 26 along the whole height of the mould blocks.

[0021] Figures 6a and 6b show two alternative constructional solutions for the wedge bar 40. In figure 6a the wedge bar 40.1 may be formed of a machined bar, one solid piece along its whole length and having a number of cylindrical locking portions 42 with a larger diameter and loosening/tightening portions 44.1 conically converging therefrom. Another alternative is to assemble the wedge bar 40.1 from a number of partial assemblies comprising a locking part 42 and a loosening/tightening part 44.1 , whereby the partial assemblies are fastened to each other by means of e.g. thread- type fastening. Such an assembly of the wedge bar from partial assemblies may be done either beforehand or at the stage where the wedge bar is used for connecting the mould blocks to each other. Thus it is possible to push the uppermost partial assembly of the wedge bar to the holes in the brackets of the uppermost pair of stiffeners, to push the lower end of the next partial assembly of the wedge bar to the holes in the brackets of the second pair of stiffeners and to thread the above mentioned partial assembly by its upper end to the lower end of the first partial assembly and so on.

[0022] Figure 6b illustrates another advantageous constructional alternative 40.2 of the wedge bar 40. The wedge bar 40.2 is formed either by a machined bar, one solid piece along its whole length and having a number of cylindrical locking portions 42 with a larger diameter, first loosening/tightening portions 44.2 converging conically therefrom and cylindrical second loosening/tightening portions 46 having a smaller diameter. Another alternative is to assemble the wedge bar 40.1 from a number of partial assemblies comprising a locking portion 42, a first loosening/tightening portion 44.2 and a second loosening/tightening portion 46, whereby the partial assemblies are fastened to each other by means of e.g. thread-type fastening, as described above.

[0023] In both of the above constructional alternatives the number of locking and loosening/tightening portions or the number of partial assemblies consisting thereof preferably corresponds with the number of the stiffeners of the mould block. Thus the distance between the cylindrical locking portions 42 of the wedge bar 40 corresponds with the distances between the stiffeners. Figures 5, 6a and 6b also show how the upper end of the wedge bar 40 is provided with a lifting eyelet 48 by means of which the wedge bar may be lifted when the locking between the mould blocks is opened. A flange 50 is provided between the eyelet 48 and the uppermost locking portion 42 of the wedge bar 40, the flange supporting the wedge bar 40 so that the bar may be left suspended by the bracket of the uppermost stiffener after locking. The flange 50 and the lifting eyelet 48 may also be of one piece which may, in addition to being an integral part of the wedge bar 40, also be e.g. a separate part which may be threaded into a threaded hole in the wedge bar 40. The flange 50 may also be utilized when lifting the wedge bar upwards. In this case, a tool resembling a crowbar is pushed under the flange for lifting the wedge bar. Additionally the uppermost loosening/tightening portion 44.1 , 44.2 or 46 is preferable, but not necessarily, provided with a hole 49, into which a clevis pin may be pushed after the wedge bar has been lifted in a suitable amount to open the locking between the mould blocks. Thereby the locking of the mould blocks remains opened until the pin is removed from the hole 49 and the wedge bar moves downward/is pushed down to lock the mould blocks into casting position. In case the vertical support of the wedge bar has been arranged in some other way, the above- mentioned flange is not needed. In this case the lifting eyelet may be removed from the end of the wedge bar, if necessary, whereby the upper end of the wedge bar preferably remains on the same level with the bracket of the uppermost stiffener and is may not cause a danger of tripping during casting for people working on the mould.

[0024] Figure 7 shows an alternative to the wedge bar shown in figure 6a and 6b according to a preferred embodiment of the present invention. In this embodiment the wedge bar 140 consists of a number of wedge parts comprising at least a locking part 142 and a loosening/attachment part 144 attached by means of arms 152 to a unitary bar 147 extending the whole length of the mould. The upper end of the bar 147 comprises a lifting eyelet 148 by means of which the lifting of the wedges necessary for the loosening of the mould blocks may be carried out. The lower end of the uppermost wedge part is provided with a hole 149 into which the clevis pin may be located as in previous embodiments. One of the advantages of this embodiment when compared with the solution of figures 6a and 6b is that when it is desirable to fully separate the adjacent mould blocks from each other it is not necessary to lift the whole wedge bar away. Thereby it is sufficient that the wedge bar be lifted the height of one wedge part, whereby the wedge parts no more contact the holes of the brackets but instead the wedge bar is allowed to move sideways away from the mould blocks. It should additionally be noticed that the wedge bar may be lifted, in addition to using the eyelet 148 also by means of utilizing the flange 150 of the uppermost wedge part as described above. As far as the use of the wedge bars is concerned, it should be understood that it is not necessary to use them for locking the mould blocks, but the invention also relates only to fastening the mould blocks of the internal or external mould portion to each other.

[0025] Figures 8a and 8b show the connection of external mould portions 20.1 and 20.2 to each other. As already shown in figures 5 and 6a, 6b and 7, the mould blocks are connected to each other by means of a wedge bar 40 or 140 pushed through holes 28 in brackets 26 or the like. Figure 8a shows a situation in which the mating surfaces of the mould blocks 20.1 and 20.2, including the sealing member 30, are pressed against each other so that the external mould forms a closed ring inside of which there is a casting space, in which the casting of the building module may be carried out. The pressing together of the mating surfaces of the mould blocks 20.1 and 20.2 is carried out by dimensioning the brackets 26.1 and 26.2, their attachment to stiffeners 24 and the holes 28.1 and 28.2 in brackets 26.1 and 26.2 so that when the holes in the brackets are aligned the mating surfaces of the mould blocks (as well as the sealing member 30, if used), are pressed together. The holes 28.1 and 28.2 of the brackets 26.2 and 26.2 are aligned during assembly of the mould by pushing the wedge bar 40 or 140 through the holes 28.1 and 28.2, whereby the conical part 44.2/144 of the wedge bar 40/140 guides the locking part 42/142 of the wedge bar 40/140 into holes 28.1 and 28.2, whereby the holes 28.1 and 28.2 are aligned and the mould blocks are pressed together into a sealed mould.

[0026] Figure 8b illustrates a situation in which the connection between the mould blocks 20.1 and 20.2 is opened. This is performed by moving the wedge bar 40/140 axially so that either the lower end of the conical portion 44.1/144 of the wedge bar 40.1 (the wedge bar of figures 6a and 7) or the cylindrical part 46 of the wedge bar 40.2 having a smaller diameter (the wedge bar of figure 6b) is aligned with the holes 28.1 and 28.2 of brackets 26.1 and 26.2, whereby the brackets 26.1 and 26.2 and with them the mould blocks 20.1 and 20.2 may slightly slide in relation to each other and open the space needed between the cast building module and the mould blocks 20.1 and 20.2 for lifting either the external mould portion (mould blocks 20.1 and 20.2) or the building module from the casting station. In this stage the clevis pin, if used, is inserted in the hole 49/149 of the wedge bar (figures 6a, 6b and 7).

[0027] Figures 9 and 10 illustrate the internal mould portion 60 of the mould for a building module according to the present invention. It consists of a number of mould blocks 60.1 , 60.2, 60.3 and 60.4. Each mould block consists of a mould plate 62 and the stiffeners 64 supporting it from the inside. According to an advantageous embodiment of the invention at at least one end of the mould plate 62, the internal vertical side of the mould plate 62 is provided with, preferably fastened thereto, a resilient sealing member 70 by means of which the connection area between the mould blocks is kept sealed during casting. In other words, the end surface of the adjacent mould plate 62 is pressed against the sealing member 70. Figure 10 further illustrates how the inner surface of the mould block 60.2, i.e. the surface facing away from the casting, is in this embodiment provided with a support batten 72 supporting the resilient sealing member 70 and preventing it from being pressed inwards. The resilient sealing member may naturally be fastened (such as glued), not only to the mould plate side surface facing away from the casting, but also to the end surface of the mould plate 62, in some cases to both surfaces. The resilient member is made of rubber, plastic or some other applicable compressible material. [0028] The above-mentioned stiffeners 64 are located, similar to the external mould blocks, in a preferably essentially horizontal direction either with constant intervals or with the intervals determined by the casting pressure on the whole height of the mould block. Brackets 66 with their holes 68 are attached or otherwise arranged in both ends of the stiffeners 64 of each mould block, into which holes the wedge bar according to figures 6a, 6b and 7 may be pushed. The operation of the wedge bar is quite similar to that described above, i.e. the mating surfaces of the adjacent mould blocks are pressed against each other when the locking portion of the wedge bar is aligned with the holes 68. However, unlike the external mould portion, with the internal mould portion, there is no need to increase the clearance between the blocks when opening the locking between the blocks made by means of the wedge bar. When the locking between the blocks is released by moving the wedge bar axially the blocks are allowed to move away from the casting, i.e. inwards, which in practice means that the resilient member between the blocks must be compressed. Immediately after the locking between the blocks is opened, any tension accumulated in the stiffeners in the form of bending is released and the resilient member is slightly compressed. Next, when lifting of either the mould portion or the casting is commenced, the unevennesses in these increase the compression between the casting and the blocks, whereby the compression of the resilient member is increased. Thus the resilient member must be dimensioned so that on the one hand its compressibility is sufficient for allowing the lifting of the mould portion or casting from the casting station, and on the other hand so that its sealing effect is sufficient for keeping the concrete to be cast inside the casting space even when the compression isn't strong.

[0029] It should also be noted that even though the above description discloses brackets attached to the stiffeners, preferably by welding, for connecting the mould blocks to each other, it is also possible to use some other kind of connection member. The bracket may be replaced, for example, with an eyelet connected to the stiffener by means of a thread connection or the actual stiffener may be provided with holes for the wedge bar. When describing the wedge bar, it is also useful to notice that the converging portions of the wedge bar do not necessarily have to be cones, but also pyramid-like forms are possible. The converging portions do not have to be symmetrical, either, and they don't have to be similar on different sides of the wedge bar. In other words it is quite possible that the hole in the bracket or the like is angular, such as square, and the wedge portion of the wedge bar is formed by a square bar, two sides of which are provided with the necessary wedge-like indentations.

[0030] Figure 11 shows the mould for a building module according to another preferred embodiment of the invention. The mould for a building module consists of, as in the previously described embodiment, internal and external mould portions, 120 and 160, respectively. The external mould portion consists of four external mould blocks 120.1 to 120.4 and the internal mould portion similarly consists of four internal mould blocks 160.1 to 160.4 Each mould block comprises, as has been disclosed above, a mould plate 122, 162, located against the concrete mass of the casting, and a number of stiffeners 124, 164 preventing the bending of the mould plate when the concrete is cast. The stiffener may be, for example, a flat bar or more preferably an I- or C-beam. In principle the use and the operation of the mould for a building module according to this embodiment is similar to that of the previously described mould for a building module. In other words, the blocks of the mould for the building module are tightened and locked into their casting stations by means of wedge bars or other applicable locking apparatuses or members arranged in connection with, for example, stiffeners 124, 164, preferably by means of brackets 126, 166. However, at least one of the brackets may be replaced, as has already been described above, by continuing the stiffener past the mould plate and by arranging a bracket into the stiffener of the adjacent mould block or by continuing the stiffeners of both mould blocks past the mould plates, whereby the extensions of the stiffeners are overlapping and the fastening holes for the wedge bar may be arranged directly to the stiffeners. According to this embodiment, the locking may generally be arranged to between the stiffeners of adjacent mould blocks.

[0031] Figure 12 is an enlargement of the upper right corner of a mould for a building module of figure 11 in casting position, i.e. in a position in which the adjacent mould blocks 120.1 and 120.2 as well as 160.1 and 160.2 are pulled and locked into casting position, i.e. the mould blocks are tightly against each other, by means of locking means, such as wedge bars. In the figure may be seen two adjacent mould blocks 120.1 and 120.2 of the external mould portion 120 as well as their mould plates 122, stiffeners 124 and brackets 126, the holes 128 of which are in casting position aligned forced by the locking apparatus. The mould block 120.2 having the mould plate 122 extending to the level of the end of the mould plate 122 of the adjacent mould block 120.1 or past it, is preferably, but not necessarily, provided with a batten 182 extending to the inside of the mould plate 122 (the surface facing the casting), the purpose of which is discussed in more detail in connection with figure 13.

[0032] Figure 12 shows two adjacent mould blocks 160.1 and 160.2 of the internal mould portion as well as their mould plates 162, stiffeners 164 and brackets 166, the holes 168 of which are in casting position aligned forced by the locking apparatus. An essential feature of the this embodiment of the invention is that a corner piece (consisting of either one piece or a number of pieces), i.e. a preferably triangular batten 192, a second side 196 of which is positioned at the same level with the vertical end of the mould plate 162 while the first side is located against the surface of the mould plate facing away from the casting space, and the base 194 of which being beveled beveled, is attached by its first side and extending along the whole length of the mould plate to the internal (facing away from the casting) surface of the vertical end of the first mould plate 162. Another essential feature is that the end of the adjacent, second, mould plate 162 is provided with a bevel acting together with the beveledbeveled base 194 (facing away from the casting) of the comer piece 192 so that in casting position the end surface of the first mould plate, the side surface 196 of the triangular batten 192 and the surface of the second mould plate facing the casting are in the same level and act as casting surfaces. In other words the beveledbeveled surface of the vertical end of the mould plate 162 forms an obtuse angle of, preferably but not necessarily, 135 degrees (if the angle planned for the casting is 90 degrees) with the surface of the mould plate 162 facing the casting. The bevellings of the base 194 of the triangular batten, i.e. the corner piece 192 and the end of the mould plate 162 correspond to each other so that the chamfer of the end is essentially against the base 194. An alternative to attaching the corner piece 192 by welding on the rear surface of the second mould block is to arrange the batten either by glue, adhesive tape or a similar removable attachment method in connection with the surface. Thereby, if the batten is very closely against the casting, it rather detaches by itself as the mould is lifted from the casting station than causes damages to the casting. The triangular batten may, of course, also be attached (by means of welding, a magnet, glue or the like suitable method) to the end of the mould plate, whereby the end of the mould plate should be beveledbeveled so as to fit with the base of the triangle. The cross-section of the corner piece may be also mainly triangular, but its one edge may be cut in right angle with its second side so that the cut part of the corner piece may, for its part, be fastened to the end of the mould plate without the need to chamfer the end of the mould plate.

[0033] Figure 13 is an enlargement of the right upper corner of a mould for a building module when the mould for the building module is in opened position. Thus, in the situation shown in figure the locking between the adjacent mould blocks has been opened, i.e. the locking apparatuses, such as wedge bars, are either fully removed from the holes in the brackets or moved into a position allowing the mould blocks move somewhat in relation to each other. Thereby the external mould block 120.1 (only these two are shown in the figure) moves outwards (upwards in the figure) so that the end of the mould plate 122 of the mould block 120.1 slides along the surface of the mould plate 122 of the mould plate 120.2 until it meets the batten 182 arranged in the end of the mould plate 122 of the mould block 120.2, the batten being located at a distance from the mould plate 122 of the mould block 120.1 when the mould for the building module is in closed position (figure 2). In other words, a sufficient clearance (of the order of 5 to 10 mm) is formed between the plate and the set casting, allowing removal of the external mould portion or the casting from the casting station. Use of the batten 82 to limit the moving of the mould block 120.1 is not absolutely necessary, because the same function may be arranged in connection with the brackets 126. In other words the mould block 120.1 may be allowed to move outwards until the movement of the block 120.1 is stopped by the bracket 126 of the block 120.2. Further, the wedge bar left in the holes 128 may also act as the needed limiter.

[0034] The mould blocks 160.1 and 160.2 may correspondingly move in relation to each other so that the mould block 160.1 moves downwards and the mould block 160.2 moves both inwards and upwards. The bevelling of the end of the mould plate 162 of the mould block 160.2 allows, together with the beveledbeveled base 194 of the corner piece/triangular batten 192, the moving of the mould plate 162 of the mould block 160.2 simultaneously both inwards and longitudinally towards the mould plate 162 of the mould block 160.1. The practical result of this is that a clearance is formed between the mould plates 162 and the casting, the clearance allowing the removal of the mould for the building module or the casting from the casting station.

[0035] The triangular batten, i.e. the corner piece 192 may in the above embodiment be replaced by a resilient sealing member which is compressed between the vertical ends of the mould plates 162 when the locking between the mould plates 160.1 and 160.2 has been opened by, for example, moving the wedge bars.

[0036] Figure 14 shows yet another advantageous embodiment of the internal mould portion. In this embodiment the internal mould portion also consists of, in addition to the mould blocks 160.1 and 160.2 preferably triangular corner pieces 192' arranged in the corners of the mould blocks. The corner piece 192' shown in figure 14 has two sides 196' which are located in the same level with the surfaces of the mould plates 162 facing the casting when the mould is in casting position, and a so-called base 194', being the surface facing away from the casting space and forming an acute angle β with the sides 196' of the corner piece. The corner piece is attached to its place to the vertical ends of the mould plates 162 by means of e.g. magnet 198, but also e.g. silicone or other similar easily removable glue or adhesive substance or material may be used. In this embodiment the vertical end of each adjacent mould plate 162 of the adjacent mould blocks 160.1 and 160.2 is beveledbeveled so that the end surface forms an obtuse angle a with the mould plate 162 surface facing the casting. When the corner formed in the casting is a right angle, the obtuse angle is preferably 135 degrees, even though it is naturally possible to use other obtuse angles as well. The operation principle of the corner piece 192' in principle corresponds to the triangular batten 192 of figures 12 and 13. In this case, however, as the corner piece 192' is in a way loose, or at least only weakly attached to the beveled ends of the mould plates 162, the beveled ends of each mould plate 162 may slide along the end surface 194' of the corner piece 192' when the locking between the mould blocks 160.1 and 160.2 has been opened. In other words, each mould plate 162 may move both longitudinally and inwards. Thereby it is possible to produce the internal mould portion used in the production of a square building module of only two mould blocks and two corner pieces.

[0037] In practice, when lifting the internal mould portion from the casting station the corner piece may remain in place so that it is removed separately after the internal mould portion has been fully lifted from the casting station. When the mould portion is again assembled into casting position the corner piece may be fastened by means of e.g. magnets or a glue, adhesive strips or the like easily removable fasteners to the vertical end of at least one mould block. The removal of the corner piece and, simultaneously, the mould from inside the casting may be, but not necessarily, facilitated by arranging the shape of the corner piece to somewhat taper upwards, i.e. to have a wedge-like form, whereby also a similar relief (opposite wedge-like form) must be formed to the mating surfaces of the ends of mould blocks. The purpose is that when the lifting of the mould portion is commenced, the ends of the blocks immediately start to separate from the corner pieces.

[0038] Further, it should be noted about the corner piece shown above in both figures 12 and 13 as well as figure 14 that one of its advantageous shapes is triangular. The comer piece may, however, be of any shape, as long as the side or sides thereof facing the casting fulfill their purpose and the surface named as base facing the beveled end or ends of the mould plate or the two surfaces corresponding thereto allow moving at least one mould plate both longitudinally and inwards. In other words, an example of the cross-section may be a quadrilateral cross-section having one angle of 90 degrees, the opposite angle 150 degrees and the two angles therebetween both 60 degrees. Or a quadrilateral shape wherein the two adjacent angles are 90 degrees and the two other angles may be, for example, 135 and 45 degrees. Further, in case the shape of the corner to be formed in the casting is in some way exceptional, i.e. rounded or provided with a short planar parts connecting the actual wall parts (such as in an angle of 45 degrees to both wall parts), for example, the corner piece may have a curved or beveled surface facing the casting, the surface only corresponding with the shape of the corner or the said surface and a surface taking part in the casting of the actual wall part on one side or both sides of the said surface. In other words the corner piece is generally a polygon formed by straight lines or possibly curves in its cross- section, with at least one surface facing the casting space and at least one surface directed away from the casting space so that the angle β between the said surfaces is acute. [0039] In this stage it should be understood that in the solutions shown in figures 8 to 14 the wedge bars may be replaced by any kind of locking means, because the operation of the mould according to the invention is by no means dependent on the type of the locking means.

[0040] The removal of the internal mould portion from inside the cast building module according to one advantageous embodiment of the invention is described in the following with reference to figure 15. Figure 15 shows the internal mould portion 60 shown in figure 9 from the side (shown in figure 9 from below and with the mould block 60.3 removed). Firstly, a practical fact is that mostly, but not always, the space 80 remaining inside the internal mould portion 60 is covered during casting by a so-called mould cover 82 located either on the mould plates 62 of the internal mould portion 60 or the uppermost stiffeners 64 thereof and which may in the invention consist of one or more parts. In practice, there are at least three reasons for the use of the mould cover 82. Firstly it prevents the concrete to be cast from flowing into the internal space 80 of the mould portion 60. Secondly it prevents the workers moving on the level of the upper edge of the mould from falling inside the mould. Thirdly it prevents the heat introduced inside the internal mould 60 for speeding up the hardening from dissipating so easily.

[0041] Now, in this embodiment there preferably is an opening 84 provided in the center of the mould cover 82, the lifting apparatus 86, most usually a lifting bar, eyelet or wire extending to the space under the mould cover though the opening, the apparatus being fixed to a lifting means (most usually a hook) of a crane. Under the mould cover 82 the lifting apparatus 86 is connected to the lifting means 88, preferably wires, of the mould blocks (blocks 60.2 and 60.4 shown). The lifting means 88 are fastened to the mould blocks 60.2 and 60.4 from their opposite ends, preferably to the side of each internal mould portion 60 or, more specifically, to the side of the mould block. The said lifting means 88, such as a wire, a bar or a chain, forms a certain angle with the mould block 60.2, 60.4 after being fastened to the lifting apparatus 86. Preferably the angular positions (inclination angles) of the lifting means 88 used for lifting the mould blocks 60.2, 60.4 are similar. There may also be more of the 60.2, 60.4 lifting means for one mould block or its side in case the block or side is so long that it is considered necessary.

[0042] One alternative is to take the lifting means, such as wires, through the opening of the mould cover so that they are connected to one lifting apparatus, such as an eyelet or a hook, to be fastened to the lifting means of the crane above the cover. Another possibility is to attach each wire to the hook of the crane by means of e.g. a loop at the end thereof.

[0043] The most advantageous alternative (shown in figure 14) is, however, to attach the lifting means 88 of the mould blocks 60.2, 60.4 by the ends opposite to the mould blocks 60.2, 60.4 to one lifting apparatus 86 fastened to the lifting means of the crane below the mould cover 82 and to bring the said lifting apparatus 86 through the opening 84 of the mould cover 82 to be fastened to the hook of the crane. The above- mentioned block lifting means 88 are preferably fastened by their ends facing the mould blocks 60.2, 60.4 to the mould blocks. Preferably the attachment point is arranged so that it is supported by all stiffeners 64 of the rear surface of the block, for example via a beam 90 arranged on the inside edges thereof. The actual fastening point depends on the structure of the mould blocks, because the purpose is that during lifting the mould blocks move evenly away from the casting. Preferably, but not necessarily, the lifting means is fastened to the vertical centerline of the mould blocks. Thereby the lifting force is evenly exerted on the mould block. Should it for some reason be desired that a stronger force be exerted on the side of one vertical end of the mould block, such as for compressing the seal, the fastening point may be moved sideways closer to that vertical end. In vertical direction the attachment point is preferably, but not necessarily, slightly above the horizontal centerline of the mould block.

[0044] Another alternative for arranging the lifting means of the mould blocks is to fasten the lifting means by their ends opposite to the mould blocks to means, such as hooks, arranged in the lower surface of the mould cover so that each lifting means is positioned in the desired angular position between the mould cover and the mould block. The lifting means of the crane, such as a lifting hook, is correspondingly attached to a lifting eyelet or the like centrally attached to the mould cover. It is naturally also possible to arrange a number of lifting eyelets to the mould cover, whereby there is also a need for a corresponding amount of lifting wires or chains extending from the hook of the crane or the like. This latter method ensures that the mould cover and the mould blocks rise evenly, even if one mould block were slightly more stuck during the lifting than the others. Thus, in this additional embodiment the mould cover acts as the lifting apparatus fastened to the lifting means of the crane.

[0045] In practice the lifting of the internal mould portion takes place as follows: First, the lockings of the wedge bars are released, i.e. the lockings between the mould blocks are opened so that the mould blocks may move in relation to each other. The movement is, of course, limited by the movement clearances in the corners of the blocks. When the crane next tightens its own lifting means, the lifting means of the mould blocks are tightened so that in addition to a lifting power, a power pulling the blocks inside due to the angular position of the lifting means is also exerted on the blocks, whereby the blocks move inwards as far as the movement clearances of the corners of the blocks allow. This operation ensures that as the internal mould blocks rise from the inside of the building module, they do not damage the surface of the module, but a sufficient distance is maintained.

[0046] It should be noted that only a few of the most preferred embodiments of the invention are disclosed above. Thus, it is obvious that the invention is not limited to the above-mentioned embodiments but it may be applied in many ways within the scope defined by the appended claims. The features disclosed in connection with various embodiments may also be used in connection with other embodiments within the inventive scope and/or different assemblies may be combined from the disclosed features, should it be desired and should it be technically feasible.

[0047] It is also obvious that the mould solution according to the present invention may as well be applied to the production of round pieces. In other words the mould plate is fastened to the stiffeners forming e.g. a circumferential sector of 90 or 120 degrees for forming a mould block. Thereby three or four blocks may be used for forming a mould. The attachment of the blocks to each other may be made by means of wedge bars as has been described above. Similarly the movement of the blocks after releasing the locking of the wedge bars may be arranged as in principle described above by using pulling springs.,