AU2004100766A4 - Methods of turf production - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION INNOVATION PATENT Applicant(s): STRATHAYR PTY LTD A.C.N. 006 751 024 Invention Title: METHODS OF TURF PRODUCTION The following statement is a full description of this invention, including the best method of performing it known to me/us: 2 METHODS OF TURF PRODUCTION This invention relates to a method of producing turf.

There are many situations where there is a need to lay live turf on a substrate for immediate use. In earlier patents we have disclosed the use of randomly disposed three dimensional plastics elements sold under the trade mark ReFlex M that are homogeneously dispersed into a mixture of sand, loam or soil. Grass is grown through this mixture. The roots of the grass interact with the plastics mesh elements and the substrate to provide a strong compact turf system that can be used almost immediately after laying.

It is usual to prepare turf of this kind on a farm and then roll up strips of the turf, transport the strips to the site and then lay them for immediate use.

Thickness of the turf varies depending on its use; thick turf product is a popular size that can be laid for immediate use in a variety of environments including a sporting field.

A problem has been encountered in the production of turf systems of the kind described above in the inconsistency of the thickness of the finished turf. It has been discovered that there can be between 10mm and variations in thickness which means that in laying long rolls of the turf there is frequent need to cutout and replace sections that are either too thin or too thick. The unevenness of the turf provides an uneven and unsightly surface which substantially reduces the efficiency and operative effect of the product.

It is these issues that have brought about the present invention.

H:\melindaf\keep\Speci' s\METHODS OF TURF PRODUCTION.doc 10/09/04 3 According to one aspect of the present invention there is provided a method of producing a turf product comprising the steps of: homogeneously mixing reinforcing elements with a substrate of sand or soil, evenly distributing the mixture over a flat surface, compressing the distributed surface, passing a rotary trimmer progressively over the surface to trim the surface to a desired thickness whereby the trimmer removes and ejects the trimmed material, and producing grass on the trimmed surface.

The reinforcing elements are preferably three dimensional plastics mesh or fibre or fibrillated polymers. The substrate may be sand or soil or a mixture of sand and soil. The soil may include loam or peat moss.

The compressing step is preferably performed by rolling the surface.

The steps of producing grass may comprise positioning a bareroot or washed turf product directly on the surface, growing seeds of grass onto the surface or planting sprigs of grass onto the surface. The grass is then left to grow into the substrate to consolidate the turf product.

Further steps in the turf production method may include cutting the grown turf into elongate strips and rolling the strips into cylinders for transport. The method may also include using sheets of porous plastics or like material onto which the substrate is placed and rolling up the strips of turf on the plastics sheeting or porous substrate.

In a preferred embodiment the trimmer comprises a frame supported by wheels at the front and a roller at the rear, the frame having a rotary hoe extending transversely H:\melindaf\keep\Speci s\METHODS OF TURF PRODUCTION.doc 10/09/04 4 across the frame, the vertical position of the wheels to the frame being adjustable whereby, in use, one wheel is positioned on a reference surface and the other wheel run on the elevated surface whereby as the frame is drawn along the surface the rotary hoe removes the top surface to ensure that it is trimmed to a desired height, the frame including a conveyor to collect and transport the material trimmed off the top Surface by the rotary hoe.

An embodiment of the present invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a side elevational view of a machine for laying a substrate, Figure 2 is a perspective view of an apparatus for cutting, collecting and laying a strip of turf, Figure 3 is a front view of a trimming device, Figure 4 is a rear view of the trimming device, and Figure 5 is a perspective view of the device viewed from the front.

The preferred embodiment relates to a method and apparatus for producing turf. The production preferably takes place on a farm in an environment that provides ideal growing conditions.

Initially a wide growing area is prepared and levelled preferably by a laser grader. Alternatively a large concrete slab can be used as the base. The levelled earth or concrete slab is then usually covered with a layer of porous or non-porous perforated plastics, or a membrane of porous material that allows passage of air and water. As we have described in a number of our earlier patents, the turf product comprises selected grasses that are grown in a homogenous mixture of plastics mesh H:\melindaf\keep\Speci' s\METHODS OF TURF PRODUCTION.doc 10/09/04 5 elements sold under the trade mark ReFlex M and soil or sand. The soil may include loam or peat moss.

ReFlex'M mesh elements are 2" x 4" (50mm x 100mm) pieces of flexible polypropylene mesh. When blended uniformly within a rootzone profile the mesh elements reinforce three dimensionally, acting like thousands of springs to improve load bearing ability and resistance to compaction. The spring back action also creates a cushioning effect on impact and "bounce back" after impact.

The matrix of mesh elements, organically amended sand or loam is mixed and then poured in a spreader 10 as shown in Figure 1. A large hopper 11 is filled with the matrix which is conveyed through a horizontal conveyor 12 to a deflector plate 13 via a regulating gate 14. As the spreader 10 is drawn across the prepared area a layer of the substrate is deposited onto the area. The layer is deposited to an approximate depth of about 60mm in im wide passes. When the whole growing area has been covered with the substrate a suitable roller (not shown) which is usually a roller drawn by a tractor, though a self driven roller is also envisaged, passes over the whole area to compress the area down to an approximate height of Once the area has been rolled it is then trimmed in progressive passes using a trimmer 20 that is illustrated in Figures 3 to 5. The trimmer 20 is essentially a power driven rotary hoe that extends transversely across a housing 21 that is mounted on a frame 22 that in turn supports a horizontal conveyor 23 that communicates with an inclined conveyor 24. The conveyors 23 24 operate to transfer the material trimmed by the rotary hoe for collection. The frame 22 is supported by a wheeled bar at the front and an adjustable roller 26 at the rear. The span of the wheeled bar 25 is greater than the span of the H \melindaf\keep\Speci' s\METHODS OF TURF PRODUCTION.doc 10/09/04 -6rotary hoe. The bar 25 is mounted to the frame in a manner that the vertical height of the tyred wheels 27, 28 is adjustable. The height of the trimmer 20 above the ground surface can thus be adjusted so that it trims off the desired amount of compressed substrate as desired.

It was mentioned above that the substrate was compressed to a height of about 50mm. The trimmer 20 is then run progressively across the whole area to trim the area down to a uniform height of 40mm. The excess material is collected by the conveyor and taken from the site. As shown in Figure 3, when making a first pass the left hand wheel 27 is positioned on a reference surface, usually the ground. Because this surface does not carry the substrate the wheel is adjusted to lift the bar 25 a further 40mm to accommodate the desired height of the substrate. The right hand wheel 28 runs on the top of the compressed substrate and as the trimmer 20 completes one path approximately 10mm is removed leaving a fairly smooth even 40mm substrate. At the next path the left hand wheel 27 is lowered to the normal position. As the machine is reversed the right hand wheel 28 runs along the trimmed substrate and the left hand wheel 27, now becoming the right hand wheel runs at the higher level, i.e. on the untrimmed compressed substrate. The trimmer then trims about 10mm off the substrate in that pass and this operation is repeated until the whole area has been trimmed to the desired height of Once the substrate has been prepared to an even thickness of 40mm it is ready to receive the turf which can either be applied by directly applying strips of bareroot or washed turf or planting grass seeds or sprigs of turf. In any of the options discussed above the whole area is watered regularly and left exposed to the elements for a predetermined growing period until the grass is H:\melindaf\keep\Speci' s\METHODS OP TURF PRODUCTION.doc 10/09/04 7 fully integrated with the substrate. At the end of the growing period the turf is ready for transportation.

A cutting, collection and laying apparatus 50 is shown in Figure 2. The apparatus 50 is in the form of a transverse beam 51 which is secured across the end of the arms 52, 53 of a front end loader. The beam 51 is supported by downwardly extending spaced feet 54, 55 each of which terminates in an inwardly projecting pointed spigot 56, 57. Hydraulic cylinders 58, 59 urge the feet to pivot transversely. The spigots define means to engage the ends of a strip of turf to enable the turf to be formed into a cylindrical roll and then after transportation unrolled in its end use position. An overlay prevention guide 60 controls the position of the turf and a brake 61 controls the unrolling process.

By placing a pair of disc cutters (not shown) on the spigots 56, 57 of apparatus 50, shown in Figure 2, the cutters can make passes along the turf area thus cutting the turf into elongate strips the width of which is designated by the spacing of the discs. Once the turf has been cut it can then be rolled into a cylinder as discussed above.

It is understood that the turf can be picked up either with or without the plastics or porous membrane.

Once strips of the turf have been rolled into a cylinder and picked up they can then be loaded onto a truck for transportation.

The rolls of turf are usually 1.06m or 1.2m wide and up to 10m in length. Although the thickness is often it is understood that the process can be used to produce turf which is either thicker or thinner as the end use dictates. For instance, when used on racecourse crossovers the matrix thickness could be as large as 150mm.

H:\melindaf\keep\Speci s\METHODS OP TURF PRODUCTION.doc 10/09/04 8 The production method may also be used in the establishment of a sports field where the field is first laser levelled, a layer of sand is applied and laser levelled, and then the matrix is applied, compressed and trimmed prior to the addition of the grass.

It has been discovered that turf produced by this method provides a uniform substrate thickness enabling the turf to be laid evenly and consistently for immediate use.

Hi\melindaf\keep\Speci'a\METHODS OF TURF PRODUCTION.doc 10/09/04

Claims (6)

1. A method of producing a turf product comprising the steps of: homogeneously mixing reinforcing elements with a substrate of sand or soil; evenly distributing the mixture over a flat surface; compressing the distributed surface; passing a trimmer progressively over the surface to trim the surface to a desired thickness whereby the trimmer removes and ejects the trimmed material; and producing grass on the trimmed surface.

2. The method according to claim 1 wherein the reinforcing elements are three dimensional plastics mesh or fibre or fibrillated polymers.

3. The method according to either claim 1 or claim 2 wherein the compressing step is performed by rolling the surface.

4. The method according to any one of the preceding claims comprising the further steps of cutting the turf product into elongate strips and rolling the strips into cylinders for transportation.

The method according to any one of the preceding claims wherein sheets of porous material are positioned on the surface underneath the mixture, the method including rolling up strips of the turf product on the plastic sheets of porous material.

6. A trimmer for use with the method of any one of the preceding claims comprising a frame supported by wheels at the front and a roller at the rear, the frame having a H:\melindaf\keep\Speci' s\METHODS OF TURF PRODUCTION.doc 10/09/04 10 rotary hoe extending transversely across the frame, the vertical position of the wheels to the frame being adjustable whereby, in use, one wheel is positioned on a reference surface and the other wheel run on the elevated surface whereby as the frame is drawn along the surface the rotary hoe removes the top surface to ensure that it is trimmed to a desired height, the frame including a conveyor to collect and transport the material trimmed off the top surface by the rotary hoe. Dated this 10 th day of September 2004 STRATHAYR PTY LTD By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia H \melindaf\keep\Speci's\METHODS OF TURF PRODUCTION.doc 10/09/04