Apparatus for manufacturing wave-shape building blocks

A building block is disclosed which is intended to be arranged in substantially horizontal layers stacked upon each other without the use of mortar. The upper and lower support surfaces of the blocks are wave-shaped in two perpendicular directions in such a manner that the wave-patterns in both directions have the same amplitude and periodicity and a constant wave section over their entire extension. Disclosed also is apparatus for manufacturing the blocks, comprising at least one mold which has a bottom surface having a wave-shape corresponding to that of the block and an upper edge profile corresponding to the wave-shape of the top of the block in the longitudinal direction of the block. Means is located above the mold for supplying a casting mass to the mold and a rotary and vertically movable roll is located above the mold for levelling out and smoothing the mass at the upper end of the mold. The roll has means for cooperating with the wave-shaped upper edge profile of the sidewalls of the mold, the roll having a profile corresponding to the desired wave-shape of the block in a direction perpendicular to the longitudinal direction of the mold.

The invention relates to apparatus for manufacturing a building block of 
the kind intended to be arranged in substantially horizontal layers 
stacked upon each other, the upper and the lower defining surfaces of the 
block being in parallel relative to each other. 
The building industry demands new building elements, which are as easy to 
handle and as flexible in use as conventional building stones, but permit 
the application of more rational building methods. The erection of walls 
by means of conventional building stones requires several tedious 
operations. One such operation is, for example, that the individual stones 
upon their assembly must be jointed individually with mortar, or special 
locking members must be inserted manually into the joints. Jointing with 
mortar is a time-consuming operation, which requires high professional 
skill for obtaining a good result. The use of separate locking members 
involves an extra operation, which readily is neglected, and there is no 
possibility of checking at a final inspection whether this operation was 
carried out or not. Moreover, a supply of locking members must always be 
taken along during the assembly work. 
In Swedish patent specification No. 352,914 a building block of the hollow 
type is described, at which each lateral part includes a portion which is 
vertically offset a small distance to form projecting mounting flanges in 
one of the horizontal defining surfaces of the block and corresponding 
grooves in the other horizontal defining surface. Blocks of this kind can 
be assembled without the use of mortar, but they require special fitting 
pieces at corner terminations such as corners, window-splays and the like. 
With this type of block, furthermore, no special fixing effect preventing 
longitudinal displacement of the blocks relative to each other is 
obtained. 
It is the object of the present invention to provide apparatus for 
manufacturing a building block, which can be assembled without the use of 
joint mortar, and which renders possible simple corner terminations as 
well as fixing both in length and width direction. 
SUMMARY OF THE INVENTION 
The block manufactured according to the invention is designed so that the 
different layers can be laid offset and thereby form bonds also at 
corners. This is achieved in that the upper and lower support surfaces of 
the blocks are given a wave-shape in two substantially perpendicular 
directions, and that the wave-patterns in both directions have the same 
amplitude and periodicity and a constant wave section. For blocks with 
rectangular surfaces, said directions coincide with the length and, 
respectively, width direction of the blocks. 
For being able to arbitrarily turn the blocks, they suitably are designed 
so that the wave-patterns in said directions comprise an integral number 
of periods. The wave-pattern in the transverse direction of the blocks 
preferably comprises one single integral period. 
In accordance with the present invention the blocks are moulded by 
supplying a casting mass to molds both the bottom surfaces and the upper 
edge surfaces of the defining walls of the molds having a shape 
corresponding to the wave-shape of the blocks. The casting mass is 
levelled out and smoothed at the upper end of the mold by means of a 
rotary and vertically movable roll, which co-operates with the wave-shaped 
section of the longitudinal side edges of the mold, the movable roll 
having a section corresponding to the wave-shape in the transverse 
direction of the block.

DETAILED DESCRIPTION 
The block according to FIGS. 1 and 2 comprises two longitudinal parallel 
lateral pieces 1 and, respectively, 2 which are spaced apart by 
cross-pieces 3. The cross-pieces at the end edges of the block have a 
thickness corresponding to only half the thickness of the cross-pieces 
therebetween, thereby forming centrally in the block a number of vertical 
passages 4, which at different applications, can be utilized, for example, 
for receiving concrete mortar or insulation, or for the laying of pipes or 
electric cables. For rendering it possible to lay conduits also in the 
horizontal direction, the inner cross-pieces can be given a lower height 
than the lateral pieces, as shown in FIG. 1, so that upon the assembly a 
horizontal passage is formed in the defining surfaces between the 
different layers. Where appropriate, the thinner outer cross-pieces 3 of 
the blocks can at the building site be removed to the extent desired. 
According to the invention, the upper and lower support surfaces of the 
block are wave-shaped both in the longitudinal and transverse direction. 
The periodicity and the amplitude of the waviness are in both directions 
the same, and the waviness of the upper surface is entirely in "phase" 
with the waviness of the lower surface, i.e. said surfaces are still 
entirely in parallel. Both wave-patterns, furthermore, have a constant 
wave section over their entire extension. The length of the block in the 
embodiment shown corresponds to three integral periods while its width 
corresponds to one period. The number of periods, however, can be chosen 
as desired. In order to be able to arbitrarily turn and position the 
blocks during their assembly, it is important that both the length and the 
width of the block correspond to an integral number of periods for the 
wave-shape in question. For hollow blocks the period length and the holes 
are so to be adjusted to each other, that at bonded assembly of the blocks 
vertical passages are obtained which extend through the entire height of 
the structure. 
In FIGS. 3 and 4 the block section is shown from the end and, respectively, 
from the side. The waviness shown, thus, has substantially a sinusoidal 
shape, in such a manner, that the wave-shape in the transverse direction 
at the upper surface of the block has its maximum amplitude along the 
longitudinal central line of the block while the minimum amplitude is 
located adjacent the longitudinal lateral edges of the block. The 
wave-shape in the longitudinal direction of the upper surface of the block 
starts and, respectively, ends at the end edges of the block with a 
minimum amplitude, and there are three amplitude tops between the end 
edges of the block. The wave-shape at the lower surface of the block, 
thus, is complementary to the wave-shape at the upper surface. Said 
wave-shapes may in principle start and end in any arbitrary phase, but the 
embodiment shown offers substantial advantages, because it involves that 
all partial surfaces of the upper surface of the block have a certain 
inclination outward to the sides of the block and thereby render it 
difficult for water to penetrate into the defining surfaces between the 
different layers. The embodiment shown has the further advantage that the 
blocks when being stacked upon each other are given a very stable support. 
Blocks of the aforesaid design can, as shown in FIG. 5, be assembled by 
being stacked upon each other in horizontal layers. Due to their form, the 
blocks are thereby locked effectively in distinct positions. Since the 
lower and upper defining surfaces of the blocks are wave-shaped also in 
the transverse direction, the blocks can be arranged perpendicularly 
relative to each other, as shown at the corner in FIG. 5. By arranging the 
blocks bonded according to FIG. 5, a very stable wall structure is 
obtained at the same time as the probelm of terminations in corners and 
the like has been eliminated. By designing the blocks so that their length 
corresponds to an integral number of periods for the wave-shape, the 
blocks as already mentioned can be arbitrarily turned when they are being 
assembled. This requires also the width of the blocks to comprise an 
integral number of periods. The block described renders it also possible 
e.g. to connect inner walls to the outer walls 50 that blocks from the 
inner wall may pass out between blocks in the outer wall, as demonstrated 
at the corner shown in FIG. 5. 
When erecting outer walls, it may be suitable to place two shell walls 
built of blocks according to the invention at a certain distance relative 
to each other so that the space therebetween can be filled with an 
unbroken insulation. The two shell walls can be anchored to each other by 
means of transverse brackets, which are connected to recesses provided for 
this purpose in the blocks already at their manufacture. For reason of 
clearness, however, such recesses are not shown in the drawings. When the 
material itself is insulating, two blocks may be positioned side by side 
or, alternatively, blocks with double thickness may be manufactured. 
Building blocks according to the invention can be applied, in addition to 
house walls, masonry walls and the like, also in connection with play and 
hobby work, because the principle of the invention to give the upper and 
lower defining surfaces of the blocks a wave-shape is not restricted to 
blocks of certain definite dimensions, but can be applied to blocks of 
different sizes to be assembled by being stacked upon each other. 
The afore-described building block can be varied in several respects. The 
wave-shape shown, for example, can be exchanged against any other 
wave-shape as long as the periodicity and the amplitude thereof are the 
same in both the length and width directions of the block. The dimensions 
of the blocks in relation to the wave-shape may also be changed according 
to desire, so that, for example, also the width of the block corresponds 
to a plurality of integral periods for the wave-shape. The number and form 
of the vertical holes through the block are not concerned by the invention 
and may, of course, be varied according to desire. Also the geometric 
design of the block may, if desired, be changed to adapt to a special 
application. 
FIG. 6 shows an apparatus for the continuous manufacture of building blocks 
according to FIGS. 1 and 2. The apparatus comprises for this purpose a 
plurality of molds 5 in the form of carriages with wheels 6 rolling on 
rails 7. The molds 5 shown in FIG. 6 are each intended for simultaneously 
molding three blocks positioned beside each other. Each mold 5, as is more 
clearly apparent from FIG. 7, comprises two longitudinal outer sidewalls 
8. The space between these sidewalls is divided by two inner defining 
walls 9 into three longitudinal sections, which are intended each for 
molding one block, and in each of which molding stakes 10 corresponding in 
number to the number of desired holes in the block are provided. The 
bottom and end walls of the mold 5 are formed by a separate plate 11 to be 
lowered into the mold. Said plate is provided with apertures 12 
corresponding to the molding stakes 10 and is intended to rest upon 
longitudinal strips 14. Between said apertures, the plate is provided with 
upward projecting portions 13, which produce the aforesaid recesses in the 
inner cross-pieces in the blocks to form horizontal passages in the 
defining surfaces between the different layers. The upper surface of the 
block, thus, is formed by the plate 11 placed on the bottom of the mold. 
The waviness of the upper support surfaces of the block as shown in FIG. 1 
is brought about in that the corresponding surfaces of the plate 11 are 
given the desired waviness. In order to produce the desired waviness also 
on the lower support surfaces of the block, the sidewalls 8, partition 
walls 9, upper end surfaces of the mold stakes 10 and the end walls 15 of 
the plate 11 are provided with the corresponding waviness. The blocks are 
manufactured as follows. 
The mold 5 in the form of carriages are first provided each with a plate 11 
serving as bottom and end walls, and then are moved ahead on a path formed 
by the rails 7 to a filling station 16. The station comprises a storage 
hopper 17 containing the desired casting mass 18, for example concrete 
mortar. The hopper 17 is located above a rotary drum 19 provided with a 
plurality of cavities 20, which when upon rotation of the drum passing an 
opening in the lower part of the drum take along a certain quantity of the 
mass 18. The drum 19 is driven by a motor 21 at a relatively high number 
of revolutions, so that the molds 5 successively are filled as the 
material batches in the cavities are thrown down into the molds when they 
are passing beneath the drum 19. Owing to this batchwise filling, the 
molds are filled very well, so that the mass normally need not be 
vibrated, as it is necessary with other machines for the manufacture of 
building blocks. This elimination of vibration is a very substantial 
advantage. 
The described filling device can be varied in several respects. The 
material bins, for example, can be arranged rotary about a substantially 
horizontal shaft in any desired manner, and the number and size of the 
material bins be varied as desired. The essential requirement, thus, is 
that the casting mass in a controlled manner batchwise and very forcefully 
can be thrown down into the mold to be filled. The molds are advanced 
either continuously or in steps pass the filling station. 
The mold after having been filled with mass 18 pass a profiled roll 23, 
which is driven by a motor 22 at a high number of revolutions and provided 
with free-running rollers 24 co-operating with the upper wave-shaped edge 
surfaces of the sidewalls 8 of the mold 5, which surfaces act as cam 
surfaces. The roll is for this purpose pivotal in vertical direction. 
The profile of the roll 23, as can most clearly be seen in FIG. 8, 
corresponds to the desired wave-shape in the transverse direction of the 
blocks. The roll 23 comprises for each of the three longitudinal sections 
in each mold two outer sections 25, preferably of steel, which compress 
and smoothen the mass 18 fed into the mold. Between said sections a 
section 26 is provided which preferably is made of some softer material. 
Its primary object is to remove the mass 18 from the upper surface of the 
molding stakes 10 and to level the mass between said molding stakes. 
Due to the fact that the roll 23 is adapted to follow the waviness of the 
outer walls of the molds 5 by co-operation between the free-running 
rollers 24 and the upper edge surfaces of said walls, and as the roll 
itself has a profile corresponding to the desired waviness, it is possible 
in a continuous manufacturing process also to obtain the desired 
wave-shape at the lower surfaces of the blocks which are turned upward in 
the molds. By driving the roll 23 at a relatively high number of 
revolutions, a very fine surface smoothness is obtained also at the lower 
defining surfaces of the blocks. 
After the substance in the molds 5 has been levelled by means of the roll 
23, the molds pass to a station where the molded blocks are removed from 
the molds by a relative displacement in vertical direction between the 
plates 11 and the molds 5. The blocks still supported on the plates can 
thereafter be conveyed to a suitable room for curing, whereafter they are 
removed from the plates 11, which then like the molds 5 are returned to 
the input end of the machine. 
The apparatus described above can be varied in several respects. 
The molds, for example, can be constructed for the simultaneous manufacture 
of a desired number of blocks having varying shape and varying positions 
for the vertical passages. Also homogeneous blocks can, of course, be 
manufactured. The molds may also be provided with end walls, in which case 
the end walls of the plates can be eliminated.