AU2002301309A1 - A method for producing a building block - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant(s): MICHAEL ABDUL-AHAD Invention Title: A METHOD FOR PRODUCING A BUILDING BLOCK The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 A METHOD FOR PRODUCING A BUILDING BLOCK FIELD OF THE INVENTION The present invention relates to a method for producing a building block, and is of particular but by no means exclusive application to producing building blocks that can be fixed to a wall to create a facade.

BACKGROUND OF THE INVENTION Existing methods for producing building blocks often involve a large amount of curing time; that is, the time required for the blocks to set to a state where they can be used. Firing the blocks in a kiln can reduce the amount of curing time, but this requires the use of a large kiln which can be very expensive both to purchase and run.

Furthermore, existing methods can result in a significant number of unusable building blocks, for example where the blocks are of the type used for creating a facade on a wall or some other object. The reason so many of the blocks are unusable is because the outer surface of the blocks (that is, the surface which provides the facade) is typically made from a material which is different to the material from which the body of the block is made. These two materials typically cure at different rates which can result in the outer surface cracking.

Another problem associated with existing methods for producing building blocks is that the blocks can be difficult to handle when in their unset state. As such, the blocks are often left to partially set before being handled. For example, blocks made from concrete would fall apart if handled when the concrete is wet.

3 It would therefore be advantageous to provide an alternative method for producing a building block.

SUMMARY OF THE INVENTION According to a first aspect of the present invention, there is provided a method for producing a building block from a first material having a setting agent, and a second material which is settable by the setting agent, the method including the steps of: preparing the first material; preparing the second material; and compressing the first material and second material together such that the setting agent is urged substantially from the first material and into the second material, thereby causing the second material to set and form the building block.

The compression of the first material and the second material can reduce the curing time, and can allow the building block to be readily handled when in an unset state.

Preferably, the step of preparing the first material includes forming a layer of the first material over a surface of a mold.

Preferably, the step of preparing the second material includes forming a layer of the second material on the first material.

Preferably, the method further includes the step of placing a substance between the first material and the second material, wherein the substance minimizes the transfer of the second material into the first material.

Even more preferably, the substance includes dry 4 concrete powder.

Preferably, the step of compressing the first material includes applying about 380 p.s.i to the second material.

Preferably, the method further includes the step of adding a groove to a surface of the building block, wherein the grooves assist in securing of the building block to an object.

Even more preferably, the surface includes a rear surface of the building block.

Preferably, the method further includes the step of applying a sealer to the building block so as to retain the lustre thereof, wherein the sealer protects the outer surface of the building block.

Preferably, the method further includes the step of spraying the building block with the setting agent to assist in the setting of the second material.

Preferably, the first material provides the building block with a desired appearance.

Preferably, the first material includes marble dust or crushed brick, and the setting agent includes water.

Preferably, the second material includes concrete.

According to a second aspect of the present invention, there is provided a building block produced by the first aspect of the present invention.

5 BRIEF DESCRIPTION OF THE DRAWINGS Notwithstanding any other embodiments which may fall within the scope of the present invention, a preferred embodiment of the present invention will now be described, by way of example only, with reference to the accompanying figures, in which: Figure 1 illustrates the equipment for carrying out a method for producing a building block according to the preferred embodiment of the present invention; and Figure 2 illustrates a building block produced by a method according to the preferred embodiment of the present invention.

THE BEST METHOD FOR PERFORMING THE INVENTION As shown in figure 1, equipment 1 for carrying out a preferred method for producing building blocks according to the preferred embodiment includes a hydraulic press 3 and a mould 5, the latter of which is typically securely fitted to a bench 7.

The method of the preferred embodiment includes preparing a first material which includes a setting agent.

The first material also typically consists of a substance which provides the building block with a desired look. For example, the desired look could be that the building block is made from a particular material such as sandstone or terracotta. In the case where the desired look is sandstone, a substance such as marble dust can be used. To achieve a terracotta look the substance can be crushed red bricks. The substance is typically mixed with sufficient water to create a relatively thick paste. In the preferred embodiment, the water used to create the paste acts as the setting agent.

6 As illustrated in figure 2, a layer of the paste 9 is then placed in the bottom of the mould 5 to a thickness of around 0.5 lcm. The thickness of the paste layer 9 can vary depending on the user's requirements. As can be seen in figure 2, the bottom surface 11 of the mould preferably has an uneven finish which adds to the desired look of the building block.

The method also includes the step of preparing a second material which is settable by the setting agent contained in the first material, which in the preferred embodiment is the water in the layer of paste 9. The second material forms the main body (or part) of the building block, and thus it is preferable that the second material be relatively cheap. Typically, the second material is concrete made from a mixture of river sand, beach sand, gravel as aggregate and cement. Whilst not essential, preparation of the second material includes lightly sprinkling the dry concrete powder with water such that it is still in a substantial powder form. The lightly sprinkled concrete is then screened to remove any lumps that may have formed as a result of the light sprinkling.

Lightly sprinkling the concrete assists the concrete in setting and improves its consistency. A layer of the concrete 13 (in dry form) is then placed into the mould on top of the paste layer 9 (see figure The thickness of the concrete layer 13 can vary depending on the needs of the user, but it would typically be around 2 4.5cms thick for building blocks used to create a wall facade.

It is possible that some of the second material (concrete) may seep into the first material (paste layer) shortly after being placed thereon. The effect of this is that the actual look of the building block might differ from the user's desired look. This is because an amount of second material may seep into the layer of paste 9 7 potentially causing discolouration of the paste layer 9. In order to minimize this problem, a relatively thin layer of a substance 15 can be placed between the paste layer 9 and layer of concrete 13. Typically, the layer of substance is concrete powder and need only be around 0.Scms thick.

Once the layer of paste 9 and layer of concrete 13 are in place (and optionally the layer of substance the hydraulic press 3 is used to apply around 380 p.s.i of pressure to the layer of concrete 13. The mould 5 is typically configured to produce blocks having a width of about 20cms and a length of around 45cms. This means that that the pressure of 380 p.s.i equates to about 60 tons of pressure. To ensure that the pressure is distributed evenly, the hydraulic press 3 includes a plate 17 which covers the layer of concrete 17. The pressure need only be applied for a short period of time, a period of around 15 sec is sufficient for blocks having an overall thickness of around 2 4.5cms. Where thicker blocks are made, the duration for which the pressure is applied is likely to be longer.

Applying the pressure to the layer of concrete 13 causes the water in the layer of paste 9 (that is, the setting agent) to be drawn out of the paste layer 9 and into the layer of concrete 13. The transfer of water between the layers 9 and 13 causes the paste layer 9 to dry and set, and the layer of concrete 13 to set. The pressure applied to the layer of concrete 13 also assists in bonding the layers 9 and 13 together.

Once the pressure is released from the layer of concrete 13, the resultant building block can be readily removed from the mould 5 by, for example, disassembling the sides of the mould 5. When removed from the mould 5 the building block can be stored to allow the curing process to be completed. When stored, the building blocks are a preferably lightly sprayed with the setting agent (which in the preferred embodiment is water) to assist in the curing process. Depending on the thickness of the building block and the conditions under which it is stored, it is envisaged that the required curing time would be around two days for a building block of about 2 4.5cms thick.

In situations were it is necessary to protect the outer surface of the building blocks from, for example, the weather, a preferred embodiment of the method preferably includes the step of applying a suitable sealer to the building block. Thus, the lustre of the building block can be preserved.

Given that the building blocks produced by the preferred embodiment of the present invention are likely to be fitted to an existing wall structure (that is, be used to create a facade), the method preferably includes the step of creating one or more grooves in the surface of the building block which is designed to be fixed to the wall structure. The grooves assist in the bonding of the building block to the wall structure, particularly where the building block is fixed to the wall structure using mortar. The grooves can be created by projections in the mould 5, or the plate 17, when the layers 9 and 13 are compressed. Alternatively, the grooves can be created manually once the unset block is removed from the mould With regard to the mould 5, it is preferable that the bottom surface 11 is made from a rubber such as AUSCAST which is distributed by Australian Urethane Systems PTY LTD of 9 Prince William Drive, Seven Hills, NSW, Australia 2147. The rubber bottom surface 11 minimizes the likelihood that the layer of paste 9 will stick to the mould 5 as a result of being compressed by the hydraulic press 3. It is preferably that the sides of the mould 5 are made from steel and can be readily dismantled so that the 9 building block can be easily removed therefrom after being compressed.

Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It should be understood that the invention includes all such variations and modifications which fall within the spirit and scope of the present invention.

It is to be understood that a reference herein to a prior art document does not constitute an admission that the document forms part of the common general knowledge in the art in Australia or in any other country.

In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprising", or grammatical variations thereof, is used in the sense of "including", i.e. the features specified may be associated with further features in various embodiments of the invention.

Claims (14)

1. A method for producing a building block from a first material having a setting agent, and a second material which is settable by the setting agent, the method including the steps of: preparing the first material; preparing the second material; and compressing the first material and second material together such that the setting agent is urged substantially from the first material and into the second material, thereby causing the second material to set and form the building block.

2. The method as claimed in claim 1, wherein the step of preparing the first material includes forming a layer of the first material over a surface of a mold.

3. The method as claimed in claim 1 or 2, wherein the step of preparing the second material includes forming a layer of the second material on the first material.

4. The method as claimed in any one of the preceding claims, wherein the method further includes the step of placing a substance between the first material and the second material, wherein the substance minimizes the transfer of the second material into the first material.

5. The method as claimed in claim 4, wherein the substance includes dry concrete powder.

6. The method as claimed in any one of the preceding claims, wherein the step of compressing the first material includes applying about 380 p.s.i to the second material 11

7. The method as claimed in any one of the preceding claims, further including the step of adding a groove to a surface of the building block, wherein the grooves assist in securing of the building block to an object.

8. The method as claimed in claim 7, wherein the surface includes a rear surface of the building block.

9. The method as claimed in any one of the preceding claims, further including the step of applying a sealer to the building block so as to retain the lustre thereof, wherein the sealer protects the outer surface of the building block.

The method as claimed in any one of the preceding claims, further including the step of spraying the building block with the setting agent to assist in the setting of the second material.

11. The method as claimed in any one of the preceding claims, wherein the first material provides the building block with a desired appearance.

12. The method as claimed in any one of the preceding claims, wherein the first material includes marble dust or crushed brick, and the setting agent includes water.

13. The method as claimed in any one of the preceding claims, wherein the second material includes concrete.

14. A building block produced by the method of any one of the preceding claims. A method for producing a building block, 12 substantially as herein described with reference to the accompanying figures. Dated this 3rd day of October 2002 MICHAEL ABDUL-AHAD By his Patent Attorneys GRIFFITH HACK