AU608815B2 - Slate paving slabs - Google Patents

Description

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'1 COMMONWEALTH OF 'AUSYRAL6 08 8o 1 0 ATENT OFFIC,!ETI.

SPECIFICATION

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MPIL OFFICER-- Class Int, Class *ICE USE: TWENTY UPLLAMti Appi cation Number odged Complete Application No, Specific~ation Lodged Published Related art, LODGED AT SWI-OFFNCE 2 1 MIAR 1988 Adelaide i A A 44 144 fr4ame of Applicant: ,,Address of Applicant:, TO BE COMPLETED BY APPLICANT PETER RICHiARD FULJTON and DAVID JBFFERY both of Angaston, State Of South Australia, Commronwealth of Australia Actual Inventor; PETER RICHARD FULTON and DAVID JEFFERY Axddress for Service: COLLISON CO., Patent Attorneys, 117 King William Street, Adelaide, South Australia, 5000, Complete Specification for the invention entitled: "SLATE PAVING SLABS" The following statement is a full description of this Invention, Including the best method of performing it known to i(t*X us: THE COM SSIONER OF PATENTS This form must be accompanied by either a provisional specification (Form 9 and true copy) or by a complete specification (Form 10 and true copy). t 56908 2 This invention relates to slate paving slabs, more particularly to pieces of slate which are to be laid on floors and other areas such a o patios, driveways and the like.

One of the problems with using slate as a paving area or floor covering, is that due to the brittle and fragile nature of the slate pieces or slabs these usually have to be individually laid in position on a base, usually of wet grout, cement or the like. Also due to this brittle nature the slate is often damaged in the transport of the slate slabs to the site of the building.

4 a I 'It is an object of this invention to provide a slate slab or piece of S• I slate which is strengthened or supported by a supporting material such as cement or concrete or the like.

It is an object of the invention to provide a method and apparatus and a paving slab produced thereby whereby a strengthening or supporting layer of cement or concrete is applied to the slate slabs or pieces before transport to the erection area.

o o It is a further object of this invention to provide a method and apparatus for the production of paving slabs or slates whereby these may be produced in a simple and economical manner without the requirement of a large area for the casting and curing o'19,5 of the cement or concrete on the slate slabs.

It is a still further object to provide a method and means for boriding the concrete or cement mix to the slate.

Thus there is provided according to the invention a method of producing a plurality of paving slabs, comprising the steps of providing a mould, providing a release agent on one surface of each piece of slate, arranging the slates in spaced parallel arrangement in the mould, and pouring cement in the intervening spaces between the parallel spaced pieces of slate, so that after curing and removal from the mould that the cement is adhered to one face only of the pieces of slate whereby the individual paving slabs can be separated due tW the release agent.

i In a further form of the invention there is provided a method of assisting in the bonding of concrete or cement mix tc the slate, said method including the steps of diluting a PVC latex glue, increasing its consistency by adding dry cement, applying the mixture to the slate, dusting with sand and allowing to dry.

Reference will now be made to the accompanying drawing which shows one form of the invention in plan.

In a preferred form of the invention, a mould 1 is provided, this being a metal mould having a base 2 and collapsible side walls 3.

An opposite pair of side walls are provided with locating means such as lugs 4, guides, or the like so that individual pieces of slate can be positioned between opposite pairs of lugs or guides to be retained in an upright position, the guides or lugs being spaced so that a space 6 exists between each piece of slate when inserted in lt the mould.

One face of the slate, the face 7 that is intended to bc the upper wearing surface, is coated with a release agent, which can be a mould oil which is commonly used in the art, Cement or concrete 8 or the like is then poured between the respective plates of slate and tamped and compacted in normal manner.

After curing of the concrete or cement 8, the mould walls 3 are collapsed and the individual slate slabs 5 with cement or concrete 8 adhered to the rear surface 9 are removed, the release agent allowing separation of the individual slate slabs.

In order to assist in the bonding of the cement to the surface of the slate, a bonding agent can be utilized, and this can be a latex type of glue. This glue can be painted onto the rear surface 9 of the slate, but it has been found that when wet concrete is poured into the intervening spaces between the slate pieces, that this wot u;;c i. -~j 4 concrete tends to liquify the latex and an efficient bond is not achieved.

It is a further aspect of this invention to provide an improved form of bond, and one method of achieving this bond is to dilute the latex glue with water and in order to increase again its consistency, dry cement is added to this diluted latex glue. This mixture is then applied to the surface 9 of the slate, for example by painting and this is then dusted with sand and allowed to dry.

S When the plates of slate are then inserted into the mould and the F concrete or cement is then poured between the separated plates, this bonding agent does not liquify and provides an excellent bond between the cement or concrete and the slate plate. The concrete may be poured into one end of the mould, which is then tilted to be inclined with the slate plates resting on the pegs, so that the concrete fills and flows from one space to the next.

I n this way the slate pieces themselves can be sliced and cut to be of a lesser thickness, that is up to 5 or 10 mm and for use as a pedestrian area the distance between the slate plates when inserted could be 35 mm thus giving a final thickness of 40 mm.

If the final use if for vehicular traffic, such as in a driveway, the plates could be spaced further apart to give a total thickness of mm, In the event that the slate pieces are twisted, a steel divider coated with a release agent could be provided in front of the twisted slate plate, the steel plate then preventing the adhesion of the concrete onto the coverea surface of the slate.

Although various forms of the invention have been described in some detail It is to be realized that the invention is not to be limited thereto but can include various modifications falling within the spirit and scope of the invention.

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Claims (8)

1.A method of producing a plurality of slate paving slabs comprising the steps of providing a mould, providing a release agent on one surface of each piece of slate, arranging the slate pieces vertically in spaced parallel arrangement in the mould, pouring concrete or cement mix in the intervening spaces between the parallel spaced slate pieces, and after curing removing the slate pieces with the concrete or cement mix adhered to one face only of the slate pieces so that the individual slate pieces are separated due to the release agent on said one face.

2. A method as defined in claim 1, wherein the mould can be collapsed to remove the slate pieces with the concrete or cement mix adhered thereto, said mould having positioning means on opposite side walls thereof to locate said slate pieces prior to and during pouring of said concrete or cement mix,

3. A method as defined in claim 1 or claim 2, wherein to assist in the adherence of the concrete or cement mix to the slate pieces the method includes the additional step of applying a mixture to the faces of the slate pieces opposite to the face having the release agent applied thereto, said mixture including a PVC latex glue.

4. A method as defined in claim 3, wherein said mixture comprises a PVC glue diluted with water and then having its consistency restored by adding dry cement.

A method as defined in claim 4, wherein said mixture is painted on the slate pieces, and then before drying is dusted with sand. -*1 ~-Y~aa~nrmxxlP~~- i -r~i 6

6. A slate paving slab when made by the method according to any one of claims 1 to

7. A method as in any one of the preceding claims wherein said mould is collapsible.

8. A mould substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing. aaaa a a a 0404 0a 4* a, a4 a 6 *P II a a a a a oaaaa,4 a a Dated this 27th day of December 1990. PETER RICHARD FULTON and DAVID JEFFERY By their Patent Attorneys COLLISON CO ^iTf~ii)i. 44 a 04i a a a a I a *4 *0$ I ii L-i i_ i li_