GB2096532A

GB2096532A - Making constructional blocks of accurate height

Info

Publication number: GB2096532A
Application number: GB8210153A
Authority: GB
Original assignee: Forticrete Ltd
Current assignee: Forticrete Ltd
Priority date: 1981-04-07
Filing date: 1982-04-06
Publication date: 1982-10-20
Also published as: GB2096532B

Abstract

The invention relates to a method and apparatus for producing constructional blocks. The blocks are produced by casting or moulding blocks by using a block press which has its plate or shoe (30, 32) Figure 2 recessed or apertured (52) in order to form excrescences or protrusions (50) on the blocks (16) Figure 3 which excrescences or protrusions can be accurately levelled before final setting or curing of the blocks. <IMAGE>

Description

SPECIFICATION Making constructional blocks of accurate height

Description The invention relates to a method of and apparatus for producing constructional blocks and has especial, if not exclusive, reference to the production of hollow partitioned blocks of a type represented by the disclosure of British patent specifcation No.

1588544, i.e. offering the advantage of being laid dry and subsequently filled, at least several courses at a time, by pouring in a settable infill such as concrete.

It will be appreciated that any constructional blocks that are first laid dry, i.e. without a mortar infill between courses, inherently require very high accuracy at least as to their heights in order most readily to achieve the desired horizontal nature of successive courses of blocks. Moulding to such accuracy in a production plant is not easily compatiblue with high production rates.

It is an object of the invention to facilitate high production rates of cast or moulded constructional blocks without, ultimately, sacrificing dimensional accuracy.

According to the invention there is provided a method of producing constructional blocks comprising casting or moulding blocks having excrescences or protrusions formed thereon and accurately levelling said excrescences or protrusions prior to final setting or curing of the blocks.

The invention also provides apparatus for producing constructional blocks by moulding or casting including a block press having its plate or shoe recessed or apertured and means for accurately levelling excrescences or protrusions of the blocks formed thereon by said recesses or apertures.

Levelling is conveniently achieved using a precisely positioned roller that is horizontal for height dimension control purposes.

The excrescences or protrusions are formed over height at moulding or casting by using a block press that has its plate or shoe recessed or apertured in order to ensure that the block has excrescences or protrusions beyond what could be finally required.

The aforementioned roller or an equivalent will then readily flatten those excrescences or protrusions precisely to the required amount and the blocks will be left to cure.

Such a method has substantial advantages, for example over a method where newly-made blocks formed conventionally have small deposits or dry cement powder accurately metered onto desired localised positions for levelling and subsequent absorption of water from the still-wet block to cure with the block itself. The method of the invention avoids accurate metering and relies only on accurate levelling subsequent to moulding.

Specific implementation of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure lisa diagram of a block production scheme; Figure 2 shows block press shoes suitable for use in Figure 1; Figure 3 shows a block cast using shoes as in Figure 2; and Figure 4 shows the block of Figure 3 after height correction.

In the drawings, a block forming station 10 includes a press mould 12 that has a hollow outer part 14 defining the exterior of three sides of the preferrd open ended hollow block 16. Inner cavity 18, partition 20, and open end-cavity 22 of the block 16 are defined by cores 24, 26 within the outer moulded part 14. The bottom of the mould is a plate 28 that is removable to carry away the block cast into the mould. That casting is done by feeding concrete into the mould between the outer part 14 and the cores 24, 26 and then pressing down plates or shoes 30, 32 that are also capable of expressing the cast block when the bottom plate 28 is lowered (or the mould parts raised).The V-shaped depressions 34,36 in the block end wall 38 and the partition 20 are conveniently formed against upper connections 40 of the mould cores, 24,26 aided by pressing action of the plates or shoes 30, 32.

It will be appreciated that the single-block mould just described will normally be part of a multi-block mould system for pressure-forming a plurality, often 6 or 8, of the still-wet blocks simultaneously, concrete or the like therefor being fed in from hopper 42 via slide 44 reciprocable between pressing operations. Such blocks are then taken away on a common bottom plate 28 for curing, the plates or shoes 30,32 automatically instigating simultaneous lowering of the plate 28 from a predetermined height above that plate. It is between removal of the blocks from the moulds and curing that height correction hereof is applied.

That is done relative to integral formations 50 on the upper edge of a block that are readily imposed by way of recesses 52 formed in the shoes 30,32.

The integral formations 50 will be above the maximum added height relative to which adjustment or correction is applied, and will normally be very much above that so that a substantial smearing of those formations 50 is required to relieve block height accuracy. That is shown done by a precisely positioned horizontal roller or rollers 54 below which cast or moulded blocks will pass on their way from the block casting station and prior to passage to curing kilns or autoclaves with their supporting plates at a prescribed position below the roller or rollers 54 on a suitable track or other conveyor 56.

The roller or rollers 54 will, of course, be capable of height adjustment in a precisely controlled manner as indicated by roller amount 58 operated by a fine lead-screw 60 in a frame 62.

CLAIMS 1. A method of producing constructional blocks comprising casting or moulding blocks having excrescences or protrusions formed thereon and accurately levelling said excrescences or protrusions priortofinal setting or curing ofthe blocks.

2. A method as claimed in claim 1 in which levelling is achieved using a precisely positioned roller which is horizontal for height dimension

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Making constructional blocks of accurate height Description The invention relates to a method of and apparatus for producing constructional blocks and has especial, if not exclusive, reference to the production of hollow partitioned blocks of a type represented by the disclosure of British patent specifcation No. 1588544, i.e. offering the advantage of being laid dry and subsequently filled, at least several courses at a time, by pouring in a settable infill such as concrete. It will be appreciated that any constructional blocks that are first laid dry, i.e. without a mortar infill between courses, inherently require very high accuracy at least as to their heights in order most readily to achieve the desired horizontal nature of successive courses of blocks. Moulding to such accuracy in a production plant is not easily compatiblue with high production rates. It is an object of the invention to facilitate high production rates of cast or moulded constructional blocks without, ultimately, sacrificing dimensional accuracy. According to the invention there is provided a method of producing constructional blocks comprising casting or moulding blocks having excrescences or protrusions formed thereon and accurately levelling said excrescences or protrusions prior to final setting or curing of the blocks. The invention also provides apparatus for producing constructional blocks by moulding or casting including a block press having its plate or shoe recessed or apertured and means for accurately levelling excrescences or protrusions of the blocks formed thereon by said recesses or apertures. Levelling is conveniently achieved using a precisely positioned roller that is horizontal for height dimension control purposes. The excrescences or protrusions are formed over height at moulding or casting by using a block press that has its plate or shoe recessed or apertured in order to ensure that the block has excrescences or protrusions beyond what could be finally required. The aforementioned roller or an equivalent will then readily flatten those excrescences or protrusions precisely to the required amount and the blocks will be left to cure. Such a method has substantial advantages, for example over a method where newly-made blocks formed conventionally have small deposits or dry cement powder accurately metered onto desired localised positions for levelling and subsequent absorption of water from the still-wet block to cure with the block itself. The method of the invention avoids accurate metering and relies only on accurate levelling subsequent to moulding. Specific implementation of the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure lisa diagram of a block production scheme; Figure 2 shows block press shoes suitable for use in Figure 1; Figure 3 shows a block cast using shoes as in Figure 2; and Figure 4 shows the block of Figure 3 after height correction. In the drawings, a block forming station 10 includes a press mould 12 that has a hollow outer part 14 defining the exterior of three sides of the preferrd open ended hollow block 16. Inner cavity 18, partition 20, and open end-cavity 22 of the block 16 are defined by cores 24, 26 within the outer moulded part 14. The bottom of the mould is a plate 28 that is removable to carry away the block cast into the mould. That casting is done by feeding concrete into the mould between the outer part 14 and the cores 24, 26 and then pressing down plates or shoes 30, 32 that are also capable of expressing the cast block when the bottom plate 28 is lowered (or the mould parts raised).The V-shaped depressions 34,36 in the block end wall 38 and the partition 20 are conveniently formed against upper connections 40 of the mould cores, 24,26 aided by pressing action of the plates or shoes 30, 32. It will be appreciated that the single-block mould just described will normally be part of a multi-block mould system for pressure-forming a plurality, often 6 or 8, of the still-wet blocks simultaneously, concrete or the like therefor being fed in from hopper 42 via slide 44 reciprocable between pressing operations. Such blocks are then taken away on a common bottom plate 28 for curing, the plates or shoes 30,32 automatically instigating simultaneous lowering of the plate 28 from a predetermined height above that plate. It is between removal of the blocks from the moulds and curing that height correction hereof is applied. That is done relative to integral formations 50 on the upper edge of a block that are readily imposed by way of recesses 52 formed in the shoes 30,32. The integral formations 50 will be above the maximum added height relative to which adjustment or correction is applied, and will normally be very much above that so that a substantial smearing of those formations 50 is required to relieve block height accuracy. That is shown done by a precisely positioned horizontal roller or rollers 54 below which cast or moulded blocks will pass on their way from the block casting station and prior to passage to curing kilns or autoclaves with their supporting plates at a prescribed position below the roller or rollers 54 on a suitable track or other conveyor 56. The roller or rollers 54 will, of course, be capable of height adjustment in a precisely controlled manner as indicated by roller amount 58 operated by a fine lead-screw 60 in a frame 62. CLAIMS

1. A method of producing constructional blocks comprising casting or moulding blocks having excrescences or protrusions formed thereon and accurately levelling said excrescences or protrusions priortofinal setting or curing ofthe blocks.

control.

3. A method as claimed in claim 1 or 2 wherein the excrescences or protrusions are formed over height at moulding or casting by using a block press which has its plate or shoe recessed or apertured in orderto ensure that the block has excrescences or protrusions beyond what could finally be requird.

4. A method of producing constructional blocks substantially as herein before described with reference to the accompanying drawings.

5. A constructional block made by a method as claimed in any one of claims 1 to 4.

6. A constructional block as claimed in claim 5 which is a hollow partitioned block for dry laying and filling with a settable infill.

7. A constructional block substantially as hereinbefore described with reference to and as illustrated in Figure 4 of the accompanying drawings.

8. Apparatus for producing constructional blocks by moulding or casting including a block press having its plate or shoe recessed or apertured and means for accurately levelling excrescences or protrusions of the blocks formed thereon by said recesses or apertures.

9. Apparatus as claimed in claim 8 wherein the means for accurately levelling the excrescences or protrusions is a precisely positioned roller which is horizontal-for height dimension control.

10. Apparatus for producing constructional blocks by moulding or casting substantially as hereinbefore described with reference to and as illustrated in Figures 1 and 2 of the accompanying drawings.