GB2499257A

GB2499257A - Method and equipment for treating turf

Info

Publication number: GB2499257A
Application number: GB1202448.5A
Authority: GB
Inventors: Richard John Campey; Simon Gumbril
Original assignee: RICHARD CAMPEY Ltd
Current assignee: RICHARD CAMPEY Ltd
Priority date: 2012-02-13
Filing date: 2012-02-13
Publication date: 2013-08-14
Also published as: GB201202448D0

Abstract

A method for the treatment of turf comprising grass growing in a matrix comprises removing the matrix including any thatch and other infestation by blading moving through the matrix to a predetermined depth d. The thatch and matrix may be removed to a depth above that at which grass roots are found. The method may be used to treat turf reinforced with artificial grass. All the grass growing in the matrix may be removed and fresh sand or other matrix material may be applied and the area reseeded. Also disclosed id equipment for carrying out the treatment comprises a rotor 17 rotating about a horizontal axis the rotor having blades 18 having peripherally distributed teeth 19. The bladed rotor may be helical.

Description

1

Turf Treatment

This invention relates to turf treatment, more particularly to treatment of sports playing surfaces such as football, rugby and hockey pitches, and tennis courts which, during the course of a playing season, 5 are subject to wear and tear and also suffer from a build-up of thatch, which is an accumulation of layers of partially decomposed leaves, stems and roots. Diseases and other blights including algae, moss, fungi, and slime mould can invade the turf, and may be made worse by the presence of thatch.

It is usually recommended that thatch be treated by mechanical thatching equipment, an operation usually referred to as scarification, but sometimes known as verticutting, although that term is also 10 used for the process of cutting vertically into the turf using fine blades, sometimes known as turf grooming. Scarification is recommended to be done in several treatments rather than attempting to remove all the thatch at once.

US6094860 discloses the use of artificial fibre reinforcement for grass turf areas in playing fields subject to heavy wear, and other patents and proprietary systems similarly involve the use of artificial 15 fibre reinforcement.

"Desso® Grassmaster" is a turf reinforcement system in which artificial grass fibres are injected some 20cm deep into a grass surface, projecting some 25mm above the soil. The maintenance of this system, as regards mowing, verticutting and ventilating, is said to be no different from the maintenance of ordinary turf. Mowing, of course, must be carried out with the cutter height at or 20 above the height of the artificial grass fibres, e.g. at 26mm or more if the fibre height is 25mm, otherwise they would be cut or pulled out.

The artificial grass fibres are injected into a matrix of sand, which of course has no nutritional value, and there is only a thin top layer of humus, if indeed any, so the natural grass needs to be treated with fertiliser more than it would if grown in deep soil. This exacerbates problems of disease and 25 infestation.

On this, or indeed any, turf, moreover, undesired grasses and weeds such as clover can be a problem. Clover is especially problematic on playing surfaces such as tennis courts, as it tends to be slippery. Weeds are usually treated with systemic herbicides, which take time to act and which may require several treatments over a space of weeks.

30 The present invention provides an improved method and apparatus for treating turf, including artificial grass-reinforced turf planted in a matrix of sand and/or soil.

The invention comprises a method for the treatment of turf comprising grass growing in a matrix comprising removing matrix including any thatch and other infestation by blading moving through the matrix to a predetermined depth d.

35 The depth d may be determined by sampling the matrix to establish the depth to which it needs to be removed. It may, of course, be estimated on the basis of a greenkeeper's knowledge and experience. If the matrix is badly infected it may be removed to such a depth that all the grass growing in it is removed, so that fresh sand or other matrix material may be applied and the area reseeded. However, it may be sufficient, if the infection has not penetrated too deeply, to remove thatch and matrix down 40 to a depth above that at which grass roots are found which may then regenerate without the need to reseed.

2

In some methods for reinforcing turf, artificial grass fibres are attached to a backing which is buried beneath the surface. US5489317 discloses a permanent backing, US6094860 discloses a biodegradable backing that may, however, remain in situ for two years or more. It will, of course, be important with such systems to ensure that the depth d is less than the depth at which the backing 5 would be disturbed.

The thatch, grass and matrix may be lifted by a roller rotated about a horizontal axis with teeth that may be extended below surface level. The blading may be angled with respect to the rotor axis so that there is no or substantially no part of the length of the rotor that does not have blading at some part of its circumference, and the rotor is rotated at such speed, relative to the rate of traverse over the turf, 10 that no or substantially no part of the turf is left untreated. The blading, and particularly the teeth, may be of some substantial thickness, e.g. 5-10 mm. The roller may be rotated so that the blading moves forwardly through the matrix. The blading may be in the form of hooked teeth, with the hooks facing in the direction of travel.

While it may be surprising that this can be done on natural turf, it is even more surprising that it can 15 be done on Desso® Grassmaster and other reinforced turf systems without adversely affecting the artificial grass fibres.

The invention also comprises equipment adapted for the treatment of turf reinforced with artificial grass fibres in a sand or other matrix by removing matrix to a depth d below the matrix level, comprising a horizontal roller having blading having peripherally distributed teeth at least of length d, 20 and drive means to traverse and rotate the rotor over the turf, characterised by blade height control means adapted to deploy the teeth to a depth d below the matrix level.

The blades may exhibit a saw tooth profile. The teeth may be inclined to the direction of motion, and so dimensioned that there is no, or substantially no, part of the length of the rotor that does not have a tooth at some part of its circumference. The teeth may be sufficiently narrow, however, that the 25 anchored artificial turf is simply deflected by passage of the teeth, and then springs back, without being removed or damaged. The blades may have tips reinforced against wear with, for example, tungsten or other carbide, and may be hooked.

An auger-type grass mower is known from EP0974225, which has a similar arrangement of blade for free cutting of grass, which is to say, cutting using the blades as knives, as opposed to cutting against 30 a fixed blade, scissor-fashion For this purpose the blade is set to the desired height of cut and, if used on turf containing reinforcing artificial grass fibre, would be set to cut just above the height of the artificial grass fibres. The blades also have to rotate quickly, in order to cut the grass, rather than just bend it out of the way. The teeth of that mower are set to the side by bending the blades by approximately the thickness of the metal from which they are made, and the three front edges of the 35 teeth act as cutting edges. They are said to have advantages over another free cutting blade arrangement in EP0328080 in that they further reduce the size of the clippings. By contrast, the teeth of the equipment of the present invention are not configured to cut grass, whether artificial or natural, rbut to lift thatch, matrix and natural grass from the turf, leaving artificial grass, if present, in situ.

The rotor may have double, triple or more helix blading. As in EP0974255, the blade may be made in 40 segments for ease of construction and repair.

A rotor may be made adaptable to different conditions by blading being readily removable and replaceable. If so, then it would be desirable to have an even number of helices that could be removed in pairs so as not to unbalance the rotor.

3

The rotor may be mounted on a chassis adapted for mounting on a tractor unit especially one of the kind used for turf treatment and comprising an arrangement for rotating the rotor. The chassis or tractor unit may carry blade height setting means, as well as a transmission to drive the rotor in rotation. The rotor may be associated with a collector for material lifted by the blading.

5 A method for treating turf, and one embodiment of turf treatment equipment according to the invention will now be described with reference to the accompanying drawings, in which:

Figure 1

is a cross section of turf;

Figure 2

is a cross section of artificial-grass reinforced turf;

Figure 3

is a side elevation of a rotor adapted to carry out the method of the invention;

Figure 4

is a front elevation of the rotor of Figure 3; and

Figure 5

is a diagrammatic side elevation of a turf treatment tractor incorporating the

rotor of Figures 3 and 4

The drawings illustrate a method for the treatment of turf 11, Figure 1, comprising natural grass 12, sown, particularly in sports surfaces such as tennis courts and football and rugby pitches, in a matrix 15 15 of sand, silt and clay. The grass roots 12a are connected by rhizomes 12b. Over time and as a result of mowing and wear, the turf acquires an accumulation of dead grass known as 'thatch', and can also become infested with algae, moss, fungi, slime mould and other problems.

Figure 2 illustrates turf like that shown in Figure 1, which is reinforced with artificial grass fibres 13 which extend a given height h above turf level 14, typically 25mm. This is usually sown in a matrix 20 15a of sand with just a thin upper layer 16 of humus, and can be more at risk through needing to be more heavily fertilised.

The artificial grass fibres 13 are injected a depth D, usually some 20 cm deep, through the humus 16 into the sand 15.

An infected layer is shown in Figures 1 and 2 by the bracket B.

25 The treatment method comprises lifting thatch, natural grass 12 and matrix 15, 16 with a horizontal rotor 17, Figures 3, 4, traversed and rotated over the turf 11 and having two helical blades 18 having teeth 19, in which the teeth 19 extend a depth d below the turf level 14, so that the blades move through the turf 11 pulling out thatch, natural grass 12 and matrix material.

Usually, a treatment to a depth d at which at least some natural grass, roots, crowns, rhizomes, 30 perhaps some culm, is left in the matrix will suffice, and the grass will grow back. However, when the matrix is badly infected with algae, all the natural grass may be removed by driving the blading sufficiently deep, and new matrix laid down and reseeded. So long as, when treating reinforced turf, the depth d is less than the depth D of any backing such as disclosed in US5489317 or US6094860, and, in particular with the Desso® system, any artificial grass will remain in place.

35 The teeth 19, of which only three are shown in Figure 3, extend below turf level 14, and may have a length / of 50mm or more. The teeth 19 are on blade segments 18a that are bolted to the rotor 17.

The depth d to which the teeth 19 are required to penetrate may be determined by core sampling the matrix, or estimated by the skilled greenkeeper from knowledge and experience.

4

The rotor 17 is mounted on a tractor 41, Figure 5, carrying the rotor 17 on a chassis 42 with ground wheels 43 and a blade height control screw 44 adapted to deploy the teeth 19 below turf level 14. The tractor 41 is driven to traverse the rotor 17 over the turf so deployed and has a power take-off transmission 45 to rotate the rotor 17 so that the blades 19 move through the turf 11 pulling out thatch, 5 natural grass 12 and matrix material, soil and/or sand. The rotor is driven so that the hooks drive into the turf as it moves forward, as shown by the arrows on Figure 4. The material lifted from the turf is collected in a grass box or bag, not shown, via a chute 46, for disposal.

The height control screw 44 is adapted to extend the blades 19 as deep as may be desired into the soil 16.

10 The blades 19 have a saw tooth profile, with the saw teeth inclined to the direction of motion, the teeth being so dimensioned that the anchored artificial turf is deflected by passage of the tooth, and then springs back, without being removed or damaged. The teeth 19 have tips reinforced against wear with, for example, tungsten or other carbide, and are hooked in shape.

There may be more than the two helical blades 18 as illustrated. There may be three, for example, but

15 if the number of blades is even, they may be removed in pairs to reconfigure the rotor without unbalancing it. Such reconfiguration may be desirable to give more or less intensive treatment, or, for example, to leave furrows in the surface into which treatment media may be introduced, such as disinfectant, weed treatment, fertiliser and so forth, before backfilling with fresh matrix and perhaps reseeding.

20 Treatment as described can be carried out using equipment as described attached as an implement on tractors conventionally used for turf treatment, yet can selectively remove the top surface of turf evenly, ready for resurfacing without requiring the use of heavy ploughs and graders.

25

5

Claims

Claims:

I A method for the treatment of turf comprising grass growing in a matrix comprising removing matrix including any thatch and other infestation by blading moving through the matrix to a predetermined depth d.

5 2 A method according to claim 1, in which the depth d is determined by sampling the matrix.

3 A method according to claim 1, in which the depth d is such that all the grass growing in it is removed.

4 A method according to claim 3, in which fresh sand or other matrix material is applied and the area reseeded.

10 5 A method according to claim 1 or claim 2, in which thatch and matrix are removed to a depth above that at which grass roots are found.

6 A method according to any one of claims 1 to 5, in which the thatch, grass and matrix are lifted by a roller rotated about a horizontal axis with blading with teeth that may be extended below surface level.

15 7 A method according to claim 6, in which the blading is angled with respect to the rotor axis so that there is no or substantially no part of the length of the rotor that does not have blading at some part of its circumference.

8 A method according to claim 7, in which the rotor is rotated at such speed, relative to the rate of traverse over the turf, that no or substantially no part of the turf is left untreated.

20 9 A method according to any one of claims 6 to 9, in which the blading, and particularly the teeth, are of some substantial thickness, e.g. 5-10 mm.

10 A method according to any one of claims 6 to 9, in which the roller is rotated so that the blading moves forwardly through the matrix.

II A method according to any one of claims 6 to 10, in which the blading is in the form of 25 hooked teeth, with the hooks facing in the direction of travel.

12 Equipment adapted for the treatment of turf, including turf reinforced with artificial grass fibres in a sand or other matrix by removing matrix to a depth d below the matrix level, comprising a horizontal roller having blading having peripherally distributed teeth at least of length d, and drive means to traverse and rotate the rotor over the turf, characterised by blade height control means

30 adapted to deploy the teeth to a depth d below the matrix level.

13 Equipment according to claim 12, in which the blades exhibit a saw tooth profile.

14 Equipment according to claim 12 or claim 13, in which the teeth are inclined to the direction of motion, and so dimensioned that there is no, or substantially no, part of the length of the rotor that does not have a tooth at some part of its circumference.

35 15 Equipment according to any one of claims 12 to 14, in which the teeth are sufficiently narrow that any anchored artificial turf is simply deflected by passage of the teeth, and then springs back without being removed or damaged.

6

16 Equipment according to any one of claims 12 to 15, in which the blades have tips reinforced against wear with, for example, tungsten or other carbide.

17 Equipment according to any one of claims 12 to 16, in which the blades are hooked.

5 18 Equipment according to any one of claims 12 to 17, in which the rotor has double, triple or more helix blading.

19 Equipment according to any one of claims 12 to 18, in which the blade is made in segments for ease of construction and repair.

20 Equipment according to any one of claims 12 to 19, in which the rotor is made adaptable to 10 different conditions by blading being readily removable and replaceable.

21 Equipment according to claim 19, in which the rotor has an even number of helices that can be removed in pairs so as not to unbalance the rotor

•.'????.• INTELLECTUAL

*.*. .V PROPERTY OFFICE

7

Application No: GB 1202448.5 Examiner: Bryony Barcelo

Claims searched: 1-21 Date of search: 8 June 2012

Patents Act 1977: Search Report under Section 17

Documents considered to be relevant:

Category

Relevant to claims

Identity of document and passage or figure of particular relevance

X

1,5-8, 10, 12-16

W02011/152719 A1

Maredo et al; see figure 4 and page 6 lines 12-33

X

1,6, 11-lS, 15-17, 19, 20

EP1632120Al

Bosch GmbH; see figures 6-7

X

1,5,6, 10, 12, 13, 15,16

FR2384430 Al

Bielefelder; see figures 1 and 2

X

1,5-10, 12, 16, 18,21

DE2745667 Al

Hoffman; see figure and abstract translation

X

1,5-8, 10, 12, 14, 16, 18, 20,21

FR2881917 Al

Amazone Machines Agricoles SA; see figures 2-4

X

1,5-10, 12, 14-16, 19, 20

CN201422240 Y

Changzhou Create Appliance Co Ltd; see figures 6 and 7 and abstract translation

X

1,5,6, 10, 12, 13, 15,16

US7337601B1

Toro Co; see column 4 lines 14-31 and figure 2

X

1,3,4

US2004/040725 Al Stevens; see figure 1

Categories:

X

Document indicating lack of novelty or inventive

A

Document indicating technological background and/or state

step

of the art.

Y

Document indicating lack of inventive step if

P

Document published on or after the declared priority date but

combined with one or more other documents of

before the filing date of this invention.

same category.

&

Member of the same patent family

E

Patent document published on or after, but with priority date

earlier than, the filing date of this application.

Field of Search:

Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk

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*.*. .V PROPERTY OFFICE

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Search of GB, EP, WO & US patent documents classified in the following areas of the UKC :

Worldwide search of patent documents classified in the following areas of the IPC

A01B; A01G

The following online and other databases have been used in the preparation of this search report

WPI & EPODOC

International Classification:

Subclass

Subgroup

Valid From

A01B

0045/02

01/01/2006

A01G

0001/12

01/01/2006

Intellectual Property Office is an operating name of the Patent Office www.ipo.gov.uk