WO2010082829A1

WO2010082829A1 - Device for cleaning artificial grass and method for treating a substrate

Info

Publication number: WO2010082829A1
Application number: PCT/NL2010/050026
Authority: WO
Inventors: Anton Cornelis Bos
Original assignee: Redexim B.V.
Priority date: 2009-01-19
Filing date: 2010-01-19
Publication date: 2010-07-22
Also published as: NL2002429C2

Abstract

The invention relates to a device for cleaning artificial grass. The device for cleaning artificial grass comprises a frame, at least two treatment units, which are attached to the frame and directed toward the substrate, for treating the substrate, wherein a treatment unit comprises at least two rotatable brushes, which are coupled to a transfer system and are provided with brush elements which are directed toward the substrate, and a transfer system which is connected to the frame and coupled to the brushes for rotation thereof, a treatment unit being suspended in the frame so as to be rotatably bearing-mounted.

Description

Device for cleaning artificial grass and method for treating a substrate

The invention relates to a device for cleaning artificial grass and to a method for treating a substrate, such as an artificial grass field with a filler therebetween. The filler can have a grain-like structure such as sand and/or rubber, and/or a different granular material or powdered material.

Dirt can accumulate in the filler which is attached to and between the substrate formed by artificial grass. The artificial grass field can be a short-haired field, a relatively long- haired field or a long-haired field. The substrate can be a synthetic rubber canvas, drain or material. The blades of the artificial grass are surrounded by the grain-like material, thus increasing the lifetime of the artificial grass. However, dirt can also accumulate between the filler and can damage the artificial grass and/or can injure sportsmen. In addition, the soiling can lead to the formation of fungi which present a toxicological danger to sportsmen. It is therefore desirable to occasionally clean the artificial grass and in particular the filler.

The filler can coagulate as a consequence of moisture, as a result of which the filler hardens and cleaning is made more difficult. Current devices for treating/processing and in particular cleaning artificial grass and in particular the filler cannot loosen the coagulated filler without damaging the artificial grass in the process. Loosening the filler by applying a high force and loosening the filler optionally by means of a onesided movement can damage the artificial grass.

GB 2 306 306 discloses a brush machine with a central shaft to which three radial arms are connected, each having one non-driven, bearing-mounted brush. A second, separate embodiment known from GB 2 306 306 has cylinder brushes which rotate in opposite directions.

It is therefore desirable to provide a device for treating a substrate outdoors that provides improved results without thereby damaging the artificial grass.

According to an aspect of the present invention, this object is achieved by providing a device for cleaning artificial grass for outdoor use, comprising a frame and at least two treatment units, which are directed toward the substrate, for treating the substrate, the treatment unit comprising at least two rotatable brushes. A treatment unit, and in particular each treatment unit, is connected to the frame so as to be rotatably bearing- mounted. This allows the treatment unit, which comprises two or more brushes, to rotate with respect to the frame, as a result of which the rotatable brushes attached to the treatment unit do not have a fixed position with respect to the frame and are movable with respect to the frame and in this way obtain an additional degree of freedom, on top of the linear movement and the rotary movement. During rotation of the brushes, the treatment unit will additionally move with respect to the frame, thus reducing the force exerted on the substrate and in particular on the artificial grass. The additional degree of freedom will cause the resistance exerted on the substrate to decrease in such a way that no damage occurs. Furthermore, rotation of the treatment unit in which the brushes are accommodated leads to better and more uniform treatments and in particular churning-over of the filler during use.

The at least two double-rotating brushes or the rotatable brushes can be driven. Preferably, the frame comprises a transfer system which is coupled to the treatment unit and to the brushes for driving rotation of both the treatment unit and the brushes of said treatment unit. This allows the transfer system, which is coupled to a drive, for example an external drive or a drive on the frame, to be used. The brushes will in this case rotate over the substrate and are configured to churn-loose the filler between the artificial grass. The brushes will have to have sufficient hardness and rigidity for this function.

The brushes are preferably provided with brush elements directed toward the substrate, such as brush hairs which are configured for churning-loose filler between artificial grass. As a result, the ends of said brush elements are in contact with the artificial grass with the filler which can in this way be churned-loose during rotation of the brush. A brush element configured for churning-loose filler between artificial grass is sufficiently rigid and is for example characterized by a rigidity which is such that the brush hair can stand upright. The brush hair bends merely under a force which is greater than its own weight. In one embodiment, the brush element has a flexural rigidity which, in a horizontal one open end cantilever configuration, bends less than 5 degrees as a consequence of its own weight.

On the other hand, the double rotation of the brushes, obtained as a result of the rotation of the brush itself and of the supplementary rotation of the treatment unit with respect to the frame, leads to improved cleaning and to reduced use of environment- polluting materials.

In one embodiment, a treatment unit can comprise a cap or casing within which the brush elements directed toward the substrate are accommodated. This restricts the movement (splashing) of the churned-over filler. The cap is bearing-mounted to the treatment unit. The cap can be driven by the transfer system and will jointly rotate during driving.

The device can also be used for cleaning a hard substrate, such as a stone substrate. For cleaning weeds growing between paving, it is also possible for the brush to have steel hairs. This allows use of a chemical agent suppressing plant growth to be reduced or superseded.

In a preferred embodiment, the brushes are attached acentrically to the treatment unit. This allows the brushes in the treatment unit to rotate about the point of rotation of the treatment unit.

In one embodiment, the transfer system brings the brushes of a treatment unit into one and the same direction of rotation. This allows the brushes to interact in order to generate the movement of the treatment unit, as a result of which friction is reduced.

In one embodiment, the brush elements form a brush face for treating the substrate and the rotational shaft of the brush lies substantially at right angles to the brush face and in particular substantially at right angles to the substrate. This allows the brushes to be placed on the substrate and to move thereover with the complete brush face, thus providing a large brush surface which can be used to churn-over the filler between the artificial grass. In addition, the substantially complete brush face forms a carrying face on which the brush rests on the substrate. This leads to uniform wearing of the brush hairs. Furthermore, this reduces somewhat the bending-over of the hairs as a consequence of the rotation. According to this application, the rotational shaft at right angles to the brush face is comparable to brush hairs parallel to the axis of rotation.

In a preferred embodiment, the treatment unit is rotatable about an axis of rotation running substantially parallel to the rotational shaft of the brush. As a result, rotation of the brush can lead to a rotation of the treatment unit and thus to reduction of friction and thus reduces the risk of damage.

It is furthermore advantageous for the transfer system to comprise a belt, chain or cord with which brushes are connected in one treatment unit. This provides an efficient processing unit which can furthermore easily be replaced by a reserve treatment unit.

In an advantageous embodiment, the transfer system comprises an accommodated shaft bearing-mounted in the bearing of the treatment unit. This allows a drive to be transferred to the brushes directed toward the substrate via the bearing-mounted shaft of the treatment unit in which the brushes are accommodated. This leads to a particularly efficient assembly and to a treatment unit which can easily be replaced.

In one embodiment, the transfer system comprises a transmission which is coupled to the treatment unit for rotating the treatment unit with respect to the frame. This allows the rotation of the treatment unit to be set by means of the transmission, particularly when a switchable transmission is used. Furthermore, a treatment unit coupled to the transfer system allows the brushes and the churning-over brought about thereby to be implemented with various motion vectors with respect to the substrate. A combined movement of the treatment unit as the subframe to which the rotating brushes are attached is, in particular, made possible via the transfer system and in particular the transmission coupled to the treatment unit.

The device is preferably advanced over the substrate during treatment of the substrate and in particular cleaning. In one embodiment, movement and support means are attached to the frame for moving the device on the substrate. This provides a device which can be made to travel over the substrate. In one embodiment, the movement and support means are vertically adjustable. This also allows the friction force to be set.

In one embodiment, a coupling unit is attached to the frame for coupling the device to a driving vehicle such as a tractor. This allows the device to be driven over artificial grass by means of the tractor and the device according to the invention is in one embodiment suspended at the rear of the tractor. The coupling device can be used to set the height at which the device is suspended from the tractor and the pressure of the brushes acting on the artificial grass can in this way be set.

In an advantageous embodiment, the coupling unit also comprises a coupling for an external drive which is coupled to the transfer system. The external drive can be a drive on the tractor, for example a rotating shaft. Coupling to the coupling unit provides an inexpensive and efficient drive as the source for the brushes.

The invention will be further described based on an embodiment shown in the appended drawings. It will however be clear that the invention is not limited to the details of the embodiment shown, but that a plurality of embodiments are possible within the scope of the invention. Although the invention is described based on the claims as filed, and the measures mentioned in the text and advantages specified therein, the invention also includes all the non-designated advantages of the measures shown and the measures shown can, unless otherwise specifically stated, each be used per se and independently of the context in which they are shown. Those skilled in the art will be able to recognize from an explicitly or implicitly shown advantage the measures in question and if appropriate to make them the subject of protection of this application or any divisional applications thereof.

In the drawings:

Fig. 1 is a perspective plan view of a first embodiment; Fig. 2 is a perspective view from below of a first embodiment; Fig. 3 is a plan view of a treatment unit according to one embodiment; Fig. 4 is a cross section along FV-IV as shown in Fig. 3; Fig. 5 is a cross-sectional view along V-V shown in Fig. 1 ; Fig. 6 is a perspective view of a treatment unit according to one embodiment; and Fig. 7 is a cross-sectional view of another embodiment.

Fig. 1 is a perspective view of an embodiment of a device for cleaning artificial grass.

The ground surface to be treated is formed by artificial grass with filler, such as for example sand, attached between the blades of artificial grass. An artificial grass field comprises a mat with the blades of artificial grass attached thereto. For strengthening the artificial grass field and for increasing the lifetime of the field, the gap between the blades is filled up with a filler such as a plastics material or sand. Dirt can accumulate in the filler. It is therefore important to clean the filler or in any case to remove dirt from between the filler.

As a consequence of weather conditions or other influences, the filler can coagulate, thus making the artificial grass substrate hard. This makes the filler and the artificial grass field difficult to clean.

Various devices can be used for cleaning an artificial grass field. In one embodiment, a device for cleaning an artificial grass field comprises a hopper or vacuum cleaner-like application allowing the dirt to be sucked up from an artificial grass field. If appropriate, it can also be used to suck up and clean the filling material. An example of this is shown in WO 2008/060145. The device according to the invention can be added as a module to the known device.

In another application or in addition, a module can be used for cleaning an artificial grass field, a brush application being used. In this case, a brush can be rotated about an axis extending substantially parallel to the surface to be cleaned.

In one embodiment of the invention, one or more modules are used in series for cleaning an artificial grass field. The device 1 for cleaning artificial grass can be part of a series of this type. Figure 7 shows the device 78 for cleaning artificial grass as a first module mounted on a frame 2. The module 78 for cleaning artificial grass is particularly suitable for loosening coagulated filling material. Another, subsequent, module 79 can be the module 79 for cleaning filler. The churned-loose filler is for example sucked up and cleaned by the cleaning module 79. The cleaning module is schematically represented in Figure 7 and comprises a housing part 80, a cap and a drive 82. The cleaning module 79 can operate for example on the basis of suction and washing.

The embodiment shown in Fig. 1 is configured to be placed at the rear of a towing vehicle such as a tractor and has for this purpose a coupling unit 6 which can be connected to an optional coupling unit attached to a tractor. It will be clear to a person skilled in the art that a broad range of options for an embodiment of a coupling unit 6 are possible within the scope of the invention. In one embodiment, the coupling unit 6 can be configured for suspending the device 1 from a tractor.

The device 1 comprises a frame 2 to which movement and support means 4 in the form of a wheel 5 can be attached, for example at the end 3. The suspension of the wheels 5 can comprise a bearing and a steering mechanism or rotary suspension. The suspension can also comprise, close to the end 3, a height adjuster to be used for setting the height of the device above the substrate. The height adjuster can also be used to accommodate any wearing of the brush hairs. After wearing, the device can be set to a lower depth. The weight of the device can be used as a pressure means.

The height adjuster can also be used, as will be explained in greater detail hereinafter, to set the desired friction of the brushes on the substrate. In one embodiment, each of the wheels comprises a height adjuster of this type. In one embodiment, the height adjuster can be set independently for each wheel. Tilting of the device can also be set in this way.

Also attached centrally to the frame 2 is a drive coupling 7, shown in the form of a conical protective sleeve in which a drive shaft of a towing vehicle such as a tractor can be accommodated, which drive shaft can be connected to the transfer system of the device 1. As a result, it is possible to drive the transfer system via an external drive unit such as the motor of the towing vehicle. In another embodiment, a drive is placed on the frame 2 and said frame is directly connected to the transfer system.

The drive coupling 7 is coupled to the transmission 8 which converts, for example by means of conical gear wheels, the drive which is introduced into a rotation of a shaft about the axis of rotation 15. Another transmission 8 is also possible, for example utilizing a chord. The transmission 8 is accommodated in an openwork housing 70 in which a plurality of parts of the transfer system are accommodated. The housing 70 encases the transfer system and thus protects users from contact therewith.

The transfer system comprises a gear wheel 9 which is suspended in a layered manner in order to be able to rotate about the axis of rotation 15, which gear wheel 9 is connected via chains 10 and 11 to gear wheels 12 and 13 which are bearing-mounted so as to be able to rotate about axes of rotation 16 and 14 respectively. A chain tensioner 71 (which is shown merely schematically) is also accommodated in the housing 70.

A drive supplied by an external source via the drive coupling 7 will be transferred via the transmission 8 to the various axes of rotation 14-16 and cause a rotation thereof.

A housing part 18, which is open at an underside and in which treatment units 19 are accommodated with brushes 20-22 directed toward a substrate, is accommodated on an underside of the device 1. The treatment unit 19 is connected to the frame so as to be able to rotate about the axis 15. The brushes 20-22 have brush hairs which protrude toward the underside as may be seen in Fig. 2.

Fig. 3 is a perspective view of a treatment unit 30 which the brushes 20-22 form part of. The treatment unit 30 is a loose unit which is accommodated in the housing part 18 and is connected to the frame 2 in a bearing-mounted manner. The bearing-mounted suspension may be seen in Fig. 4 which shows that the bearing 46 connects the frame 2 to the treatment unit 30. The bearing 46 allows the treatment unit 30 as a whole to rotate with respect to the frame 2.

The treatment unit 30 comprises the three brushes 20-22 which are preferably suspended therein in a bearing-mounted manner and can rotate about the shafts 35-37. Gear wheels 32-34 are attached to the shafts 35-37. The chain 31 acts on the gear wheels 32-34. The chain 31 is also guided around a gear wheel 39 of the shaft 38. The chain 31 can be tensioned using the chain tensioner 40. The chain 31 can therefore transfer a rotation of the shaft 38 to the respective brushes. The chain 31 and shafts 35, 37 form part of a transfer system.

The shaft 38 is connected by means of a bearing 47 to the housing part 48 which can be securely connected to the frame 2. The housing part 48 can in this way rotate with respect to the shaft 38.

The housing part 48 is connected to the box 50, in which the brushes 20-22 are accommodated, via a second bearing 46. The housing part 48 is used for securely connecting to the frame 2 and allows rotation of the box 50 and thus of the (bulk) of the treatment unit 30 with respect to the frame 2 about one of the axes 14-16.

The brush 20 comprises a shaft 37 which is connected to the box 50 by means of bearings 45.

The device functions as follows. An external drive is connected to the transfer system via the drive coupling 7 and can be transferred to the cords 11 and 10 via the transmission 8 and is in this way coupled to the shaft 38 of the treatment unit 30. The shaft 38 can rotate in the direction indicated by the arrow 73 about the axis of rotation 14 with respect to the frame 2 on account of the bearing-mounted suspension 47. The drive supplied is transferred to the gear wheel 39 which transfers the drive supplied to the gear wheels 33-35 via the cord 31, wherein the cord will move in the direction indicated by the arrow 74. In the embodiment shown in Fig. 3 & 6, each gear wheel will rotate anticlockwise with respect to the box 50. Rotation of the brushes 20-22 is possible on account of the bearing 45.

As a consequence of the anticlockwise rotation of the brushes 20-22 and the contact thereof with the substrate, a moment will be built up by the friction which is in this case produced. As a consequence of said friction, the box 50, which hangs freely with respect to the frame 2, will be rotated in the direction indicated by the arrow 75. The rotation is possible on account of the bearing-mounted suspension of the box 50 to the frame 2 via the bearing 46. This will change the position of the respective rotational shafts 35-37 of the brushes 20-22 with respect to the frame 2. The friction which the brushes transfer to the substrate is reduced as a result of the rotation of the treatment unit 30 with respect to the frame 2 in the direction indicated by the arrow 75.

In one embodiment, the rotation in the direction indicated by the arrow 75 is controlled by means of a transmission which also couples the drive to the rotation of the treatment unit as a whole. The rotation of the treatment unit as a whole can be controlled and be configured as desired by means of switching-back of a controllable transmission.

A brush 20 has brush hairs 80 which protrude toward the substrate. The brush hairs form a brush face 81 as a result of the fact that the brush hairs have a substantially equal length. This causes a large surface area of friction contact, as a result of which bending of the brush hairs is reduced.

Fig. 5 is a cross section of the transmission 8. A conical transfer system can be accommodated in the transmission 8.

It will be clear to those skilled in the art that the invention is not limited to the embodiments shown.

Claims

1. Device for cleaning artificial grass comprising: a frame (2), at least two treatment units (19, 30), which are attached to the frame and directed toward the substrate, for treating the substrate, the treatment units (19, 30) being connected to the frame (2) so as to be rotatably bearing-mounted, wherein one treatment unit comprises at least two rotatable brushes (20, 21, 22) which are provided with brush elements (44) which are directed toward the substrate and are configured for churning-loose filler between artificial grass, and a transfer system (10, 11) which is attached to the frame (2) and coupled to the treatment unit and to the brushes of said treatment unit for rotation thereof.

2. Device for cleaning artificial grass according to Claim 1, wherein the brush element (44) has a flexural rigidity which, in a one open end cantilever configuration, bends less than 5 degrees as a consequence of its own weight.

3. Device for cleaning artificial grass according to Claim 1 or 2, wherein the artificial grass device (1) also comprises a cleaning module (79) for cleaning churned- over filler.

4. Device for cleaning artificial grass according to one of the preceding claims, wherein the treatment unit (19, 30) comprises a cap within which the brush elements (44), which are directed toward the substrate, are accommodated.

5. Device for cleaning artificial grass according to one of the preceding claims, wherein the brush elements (44) form a brush face (81) for treating the substrate, a rotational shaft (37) of the brush lying substantially at right angles to the brush face (44).

6. Device for cleaning artificial grass according to Claim 5, wherein the treatment unit (19, 30) is rotatable about an axis of rotation (14, 15, 16) which is substantially parallel to the rotational shaft (35, 36, 37) of the brushes (20, 21, 22).

7. Device for cleaning artificial grass according to one of the preceding claims, wherein the transfer system comprises a belt or chain or cord (31) which connects the brushes (20, 21, 22) in one treatment unit (30).

8. Device for cleaning artificial grass according to one of the preceding claims, wherein the transfer system comprises an accommodated shaft (37) bearing-mounted in the bearing (45) of the treatment unit (30).

9. Device for cleaning artificial grass according to one of the preceding claims, wherein the transfer system comprises a transmission (8) which is coupled to the treatment unit (19, 30) for rotating the treatment unit with respect to the frame (2).

10. Device for cleaning artificial grass according to Claim 9, wherein the transmission (8) is switchable.

11. Device for cleaning artificial grass according to one of the preceding claims, wherein movement and support means (4) are attached to the frame (2) for moving the device (1) for cleaning artificial grass over the substrate.

12. Device for cleaning artificial grass according to one of the preceding claims, wherein a coupling unit (6) is attached to the frame (2) for coupling the device for cleaning artificial grass to a driving vehicle such as a tractor.

13. Device for cleaning artificial grass according to Claim 12, wherein the coupling unit (6) also comprises a coupling (7) for an external drive, coupled to the transfer system (8).

14. Method for cleaning filler between artificial grass including advancing a device (1, 78) for cleaning artificial grass according to one of the preceding claims over an artificial grass field.

15. Method according to Claim 14, wherein the method further includes cleaning the filler using a cleaning module (79).