WO2010060156A1

WO2010060156A1 - A cleaning apparatus

Info

Publication number: WO2010060156A1
Application number: PCT/AU2009/001557
Authority: WO
Inventors: Allan Allaway
Original assignee: Allan Allaway
Priority date: 2008-11-28
Filing date: 2009-11-27
Publication date: 2010-06-03

Abstract

An apparatus for cleaning a synthetic grass surface, the apparatus comprising a elongate plenum head and a housing, the plenum head disposed within the housing and having a compressed air inlet and a plurality of air outlets spaced therealong through which air can be expelled against the synthetic grass surface for dislodgement of coarse and fine particulate material and to entrain the dislodged particulate material into the manifold, said manifold including an outlet located in an upper region of the housing for expelling the fine particulate material, and an outlet in a lower region of the housing for distributing the coarse particulate material back to the synthetic grass surface, and at least one elongate broom means mounted substantially parallel to the plenum head to contact the surface to be cleaned.

Description

A CLEANING APPARATUS Field of the Invention.

The present invention relates to an apparatus which can be used for cleaning a surface such as a synthetic grass surface as may be used as a tennis court, hockey field or other recreational surfaces. Such surfaces are generally subject to weathering and the accumulation of dust, moulds and mildew.

Background Art.

Synthetic grass surfaces typically comprise a synthetic surface from which extends tufts of simulated grass fibres of a plastic material. Sand is laid on the surface filling the spaces between the tufts so that the tufts remain substantially erect and produce a flat surface which provides a surface suitable for use as a recreational surface.

Typically synthetic grass is very durable. Sand normally collects at the bottom of the synthetic grass and grime, mould and mildew collects on external fibres of the synthetic grass leading to premature degradation and a reduction in performance.

Because the synthetic grass is porous whenever rain falls, dust and contaminants rise to the surface of the synthetic grass fibres leading to a degradation in surface quality and consequential problems for the sporting activity for which the synthetic grass is being used.

Sweeping a synthetic grass surface with a brush is normally ineffective because not ail particulate material is moved and when it is moved, it tends to disperse in all directions. Brushing is generally ineffective in breaking up aggregated particulate matter and can in fact damage the fibres of the synthetic grass surface. Brushing does not remove dust and other contaminants, it merely redistributes these contaminants which are believed to be the main cause of aggregation of sand particles, the consequential compaction of fibres and the growth of algae and moss.

Moreover, to attempt to clean an entire tennis court using such a method in conjunction with a washing detergent would be extremely time consuming. Accordingly, there is a need for an apparatus which can effectively remove particulate material as well as organic material such as mould and mildew from deep within the synthetic grass.

In the past, cleaning a synthetic grass surface has been performed with high-pressure water. Cleaning in this manner is a very untidy process and usually requires the replacement of much of the sand and also a considerable amount of re- levelling. Relevelling is difficult with wet sand and is a particularly laborious, time- consuming process. Machines for cleaning synthetic grass surfaces are also known. The machines generally pass over the surface and have a front head attachment which blows high-pressure air against the ground surface to be cleaned. The head attachment has a shroud in which a plenum chamber is located and through which plenum chamber the high-pressure air passes against the ground surface. The pressurized air was dispersed onto the synthetic grass surface using a perforated drum which expelled air at a fixed angle onto the synthetic grass surface as the machine passed over the surface. The high-pressure air breaks up any dirt, debris, moss, caked sand, dust, and the like, and some separation of dust and sand is achieved by virtue of a powerful vacuum arrangement in the head attachment. The cleaned sand passes through the baffles and back onto the playing surface, while the dust, dirt, and the like passes through an outlet and into collection bags. Because the head attachment is not very efficient in separating dust from sand, much sand also passes into the collection bags and therefore the collection bags are arranged upwardly with a lower inlet such that the heavier sand passes back through the inlet and into a sand collecting chamber. , An example of this apparatus is described in my earlier Australian patent no. 647607.

While this apparatus was satisfactory for some users, it was found that too much sand was being removed from the playing surface. The upward vertical collection bags were also quite dangerous as they were fully exposed and tended to flap in the wind. The apparatus was also not suitable for any cleaning other than separating dust from sand, and thus the apparatus was more or less limited to tennis courts.

I then developed an improved model of this apparatus in which a baffle was located within a shroud of the head attachment and above the plenum chamber, the baffle having a first leading portion joined to an inner wall of a leading portion of the shroud, and also having a trailing portion spaced inwardly from the trailing portion of the shroud. Accordingly, the baffle formed a torturous pathway for dust thrown up by the compressed air to pass through the outlet. This arrangement considerably improved the separation of dust and sand meaning that a minimum amount of sand passed through the outlet into the collection bags.

Again, while the cleaning achieved this apparatus performed was satisfactory, it was still found that too much sand was being removed from the playing surface. The machine also tended to flatten the synthetic grass fibres or force them to adopt a prone condition. This reduces the effectiveness of the cleaning performed and also the quality of the synthetic grass surface after cleaning,

I then developed a further apparatus for cleaning a synthetic grass surface, the apparatus comprising a plenum head and a manifold, the plenum head disposed within the manifold and having a compressed air inlet and at least one air outlet through which air can be expelled against the synthetic grass surface for dislodgement of coarse and fine particulate material and to entrain the dislodged particulate material into the manifold which extends above said plenum head, said manifold including an outlet located in an upper region of the manifold for expelling the fine particulate material, and an outlet in a lower region of the manifold for distributing the coarse particulate material back to the synthetic grass surface, wherein the plenum head is mounted for rotation within the manifold about a substantially vertical axis.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

Summary of the Invention.

The present invention is directed to a cleaning apparatus, which may at least partially overcome at least one of the abovementioned disadvantages or provide the consumer with a useful or commercial choice. With the foregoing in view, the present invention in one form, resides broadly in an apparatus for cleaning a synthetic grass surface, the apparatus comprising a elongate plenum head and a housing, the plenum head disposed within the housing and having a compressed air inlet and a plurality of air outlets spaced therealong through which air can be expelled against the synthetic grass surface for dislodgement of coarse and fine particulate material and to entrain the dislodged particulate material into the manifold, said manifold including an outlet located in an upper region of the manifold for expelling the fine particulate material, and an outlet in a lower region of the manifold for distributing the coarse particulate material back to the synthetic grass surface, and at least one elongate broom means mounted substantially parallel to the plenum head to contact the surface to be cleaned.

The apparatus is suitably arranged on a framework which permits easy manipulation over the surface to be cleaned. An arrangement for removing the separated lightweight matter and collecting it may also be included on such a framework. Most preferably, the framework is wheeled so that the device may be pushed or driven over the surface to be cleaned.

The plenum head is preferably an elongate member, most suitably oriented substantially horizontally. The length of the plenum head is such that it preferably extends from one side of the manifold to the other, that is, when the plenum head is oriented widthwise across the manifold, it is arranged such that it extends at approximately right angles to the direction in which the device is adapted to move or be propelled over the ground surface. The plenum head may be mounted centrally in relation to the manifold by any suitable means. The compressed air supply may be fed to the plenum head using any configuration.

The plenum head has at least one compressed air inlet mounted approximately centrally along its length, and at least one outlet of relatively reduced size which effects an increase in the velocity of the air passing therethrough.

Alternatively, the plenum head may have an inlet located at or through one end of the member which is preferably communicable with an air supply externally of the housing.

It is particularly preferred that the plenum head is elongate and tubular of substantially circular cross-section and at least one of the ends of the plenum head preferably extends through a wall of the housing. Preferably, the at least one outlet directs the air at an angle downwardly beneath the apparatus against the surface and particularly the particulate matter to be dislodged from the synthetic grass surface and entrains the dislodged material in the air flow.

Each outlet may be one or more narrow slits, nozzles or orifices. There may suitably be a plurality of outlets preferably extending substantially linearly along an arm of the plenum head or, most preferably, a multiplicity of aligned pin holes or nozzles. Preferably, the nozzles or the like are disposed and directed slightly forwardly of the plenum head. Of course, other configurations of the outlets are anticipated and the particular configuration may be chosen according to the condition of the synthetic surface or the degree of cleaning required. In one form, the plenum head may be in the form of an arm extending across the width of the manifold and mounted approximately centrally. The apparatus may be provided with a number of interchangeable plenum arm members, each having a different configuration of outlets, each arm member and configuration designed to provide different aspects of cleaning to the surface.

Suitably, the internal bore of each outlet is configured so that a venturi effect is produced by the air passing therethrough. The angle at which the outlet(s) is arranged is such as to provide maximum leverage on the particulate matter to be dislodged, whilst simultaneously directing the dislodged matter towards the port of the adjacent manifold. A suitable angle may be between 30° and 75°, most preferably about 60° with respect to the synthetic surface. The number of outlets in the plenum head will ideally be maximized so that a large number of individual jets of fast moving air can be directed against the particulate surface, thereby optimising the dislodgment forces thereon. This is particularly important when the particulate matter has formed a hard crusty surface as is quite common in tennis court surfaces. As the plenum head having the outlets extending along the length of the head is moved laterally over the surface to be cleaned, the cleaning provided may be more effective due to a variation in the angle of the air striking the surface.

The outlets may be positioned at a particular height above the surface in order to provide the cleaning effect. This height may typically be approximately 5 mm but the height may be variable by adjusting the separation of the rotating plenum arm member and the surface. Height adjustment means may be provided for this purpose.

The housing of the present invention will typically be substantially rectangular when viewed from above, The housing is normally provided with a pair of side rails which are located adjacent to ground surface when the apparatus is in use. The side rails will normally extend substantially parallel to the ground surface. The side rails preferably also used to mount the plenum head. Additionally, the at least one broom is mounted relative to the side of the housing using an upstanding armature to mount the broom in an adjustable manner so that the height of the broom can be varied.

One or more cross members may be provided between the rail members in order to brace the manifold and particularly to maintain the rail members and a spaced apart condition, Normally, there will be a forward cross member and a rear cross member. Each of the forward a rear cross members will normally be spaced from the terminal end of the rail members. The cross members may be positioned to act as a screed member and when the apparatus is in use to assist with the smoothing of the surface after cleaning.

Ground engaging members, preferably in the form of elongate cylindrical roller members are preferably provided in front of the forward cross member and behind the rear cross member. The ground engaging rollers are preferably mounted between the rail members. The rollers preferably support the weight of the manifold and the components of the apparatus mounted to the plenum head.

In addition to the roller members, a pair of slide members may be provided, one on each side in order to support at least a portion of the weight of the housing on the ground surface. These slide members will typically have a reduced triction iinish ot be made ot a reduced friction material such as 1 etlon.

The housing preferably has a forward portion which is at least partially arcuate. Preferably, one broom member is mounted in this forward portion. The housing also has a top wall extending rearwardly of the arcuate forward portion, a rear wall and a pair of sidewalls. Normally the port through which the lightweight matter is exhausted will be located through either the top wall or the rear wall of the manifold.

A further broom member may be provided in a rear portion of the housing.

The housing will typically be manufactured of a light metal but it is anticipated that some instances, a heavy duty (to resist the abrasive effect) plastic may be used.

The apparatus of the invention is also provided with at least one broom member which is preferably cylindrical. Each broom will normally extend substantially across the cavity which the housing defines. The broom may be mounted either in front of the pleaded head or behind the plenum head with a pair of broom is being preferred, one forwardly and one rearwardly of the plenum head. The forward broom will preferably act to either dislodge or breakup larger detritus or it may remove leaves or the like of which have come to rest on the surface prior to the plenum head cleaning the surface. The rear broom mounted behind the plenum head, may act to smooth and/or spread the cleaned sand which falls back to the surface after dislodgement via the gas exiting the outlets in the plenum head,

Each broom may be a powered broom or may simply be a broom mounted for rotation under the frictional force of the broom surface in contacting the surface to be cleaned. It is preferred that the rear broom is powered for rotation and the direction of rotation may be substantially in the same direction as the movement of the housing over the surface to be cleaned or it may be in the opposite direction. Typically, a pair of brooms are provided, one being a drive broom and the second being a driven broom. The brooms are preferably interconnected using a drive mechanism and one or more drive belts.

The combination of the broom and the compressed gas cleans the surface and particulate material within the surface more efficiently and effectively than the prior art methods. In one form bf the present invention, one or rnore baffle plates, preferably two baffle plates, may be arranged to partially enshroud the plenum arm member to prevent the coarse particulate matter from being carried into the port and to direct the coarse particulate matter back onto the playing surface from which it has previously been uplifted. The baffle plates may take the form of curved plates arranged at spaced intervals above the plenum arm member.

In order to assist the circulation of the coarse and fine particulate matter in the manifold, a deflector can suitably be located in the region of the particulate inlet. The deflector may be a planar plate which is angled with respect to the adjacent playing surface so that particulate matter striking its surface is reflected upwardly into the housing.

In this manner, the dirt, debris and other detritus, being lighter than the sand of the surface may be separated from the sand by the deflector, In particular, the sand which is heavier may be projected upwards and having a larger weight will typically fall back to the surface. As the outlets are located substantially below the deflector, the sand may be projected upwards and strike the deflector, whereupon they may fall back to the ground surface. The dirt and debris particles being smaller and lighter, have a correspondingly smaller momentum and may be carried along with the exhausted air which is removed from the manifold through the port without being impeded by the deflector.

The plenum head and/or the nozzles may have a protective coating similar applied thereto to reduce the abrasion, attrition or scarifying effect from sand or other detritus which may be forcibly ejected from the surface being cleaned. A particularly preferred coating may have a rubber-like finish.

The lower opening can, if need be, be covered with a grill or mesh of sufficient aperture to prevent entrainment of large pieces of debris which could conceivably block the manifold or at least impede the operation thereof.

The upper region of the housing generally incorporates the port through which the lightweight matter is exhausted. The port may be simply an opening about which a deflector or similar means can be arranged if necessary to prevent the coarse, particulate matter being sucked therethrough. The coarse particulate matter may then be directed back towards the lower opening of the housing and be redistributed on the playing surface. In order to assist in the prevention of the coarse particulate matter blowing out from the sides of the apparatus, between the bottom edge of the manifold and the ground surface, a skirt may be provided. This may take the form of a flat metal plate which extends outwardly from the housing about its entire perimeter. Alternatively, skirt may be provided on the lateral sides only. As previously mentioned, the apparatus is preferably supported on a wheeled framework. Such a framework is preferably of tubular construction with thin gauge sheet metal walls for minimising the weight of the entire apparatus, A push/pull handle bar is suitably provided at waist-height for easy manipulation, and means enabling the manifold to be lowered close to the ground surface or for raising it when not in use are also included. Such means can comprise a set of pivotal linkages operated by a lever adjacent the push/pull handle.

According to a particularly preferred embodiment, the apparatus may be supported on a self-propelled machine such as a golf buggy or similar machine. The apparatus may be associated with means enabling the height of the manifold, and therefore the plenum head, to be raised and lowered relative to the ground surface to obtain the optimum height for cleaning the synthetic grass surface. The means may include a set of pivotal linkages attached to the manifold operated by a lever adjacent the push/pull handle.

An arrangement may be provided for separating the fine particulate material and removing it. This arrangement may be as simple as a filter bag similar in operation to a vacuum filter bag. More complex or advanced systems may be provided depending upon requirements. When a complex arrangement is provided for removing the separated fine particulate matter and collecting it, this will suitably comprise a cyclone and chamber in combination with a filtering system. The cyclone is conveniently connected directly by way of a flexible duct to the port of the manifold. One form of cyclone comprises a cylinder with a conical head piece which is oriented in a vertical location on the wheeled framework between the manifold and the push/pull handle. An iniet is provided in the sidewall of the cyclone at an intermedial position, and internal plates direct the entrained fine particulate matter around the inner wall towards the bottom of the cyclone to a collection chamber directly beneath it. A filtering system may be provided about an exhaust air outlet, or outlets, which is ι , . | I , preferably located in the top of the cyclone. The filtering system may compπse one or more bags of filtering material supported from a framework which extends above the outlet(s), The filtering arrangement is designed to prevent any fine particulate matter blowing into the atmosphere while permitting the exhaust air to be expelled therethrough. Compressed air used to charge the plenum head can be supplied from a portable compressor which is either carried by the support framework for the apparatus or is supplied by a separate remote compressor. In this later context, a single compressed air line preferably may supply air to an air line connected to the central inlet of the plenum arm member, and a take-off line for driving the equipment. According to a particularly preferred embodiment, the compressed air may be supplied to the surface to be cleaned at a relatively low volume, (approximately 100 cubic feet per minute) but at a relatively high pressure (approximately 250 pounds per square inch). There may be an adjustment means provided to adjust the flow rate and/or pressure at which the compressed air is provided. For example, particularly high use areas of the surface, such as those about the sendee line on a tennis court, may require a more intensive cleaning than other, less well used areas. In this situation, a higher pressure flow at a lower flow rate maybe used to clean the high use areas due to greater compaction of the surface at those areas while a lower pressure flow at a higher floλv rate may be used at the lower use areas.

It may also be a compressed air fee into the exit port from the housing in order to create a Venturi effect which may assist with removal of heavier particles. Brief Description of the Drawings.

Various embodiments of the invention will be described with reference to the following drawings, in which:

Figure 1 is a perspective view from beneath the apparatus according to a preferred embodiment of the present invention. Figure 2 is a perspective view from behind of the apparatus illustrated in Figure 1.

Figure 3 is a perspective view from the front of the apparatus illustrated in Figures 1 and 2.

Figure 4 is a view frohi the front of a jet manifold according to a preferred embodimeni of the present invention.

Figure 5 is an end view of the jet manifold as illustrated in Figure 4.

Figure 6 is a detailed view of the jet manifold of Figure 5.

Figure 7 is a view from the front of a brush housing roller according to a preferred embodiment of the present invention. Figure 8 is a view from the front of a shaft included in the brush housing roller illustrated in figure 7.

Figure 9 is a detailed view of one end of the shaft illustrated in figure 8.

Figure 10 is a view from the front of a brush assembly according to a preferred embodiment of the present invention will stop Figure 11 is a front view of a brush core used in the brush assembly illustrated in figure 10.

Figure 12 is a front view of a housing according to a preferred embodiment of the present invention. Figure 13 is a view from above of the housing illustrated in Figure 12. Figure 14 is a side view showing the internal workings of a preferred embodiment of the present invention.

Figure 15 is a schematic view of the drive arrangement used in the preferred embodiment illustrated in Figure 14

Detailed Description of the Preferred Embodiment. According to a particularly preferred aspect of the present invention, an apparatus for cleaning a synthetic grass surface is provided.

The apparatus 10 as illustrated in the Figures includes a elongate plenum head 11 and a manifold 12. The plenum head 1 1 is disposed within the manifold 12 and has a compressed air inlet 13 and a plurality of air outlets (not shown) spaced therealong through which air can be expelled against the synthetic grass surface for dislodgement of coarse and fine particulate material and to entrain the dislodged particulate material into the manifold 12. The manifold 12 includes an outlet 14 located in an upper region of the manifold 12 for expelling the fine particulate material, and an outlet (open bottom of the manifold) in a lower region of the manifold 12 for distributing the coarse particulate material back to the synthetic grass surface, and an elongate broom 15 mounted substantially barallel to the mehum heaα 11 to contact the surface to be cleaned.

As illustrated, the plenum head 11 is an elongate arm member oriented substantially horizontally. The plenum head 11 extends from one side of tne manifold 12 to the other, that is, when the plenum head 11 is oriented widthwise across the manifold 12, it is arranged such that it extends at approximately right angles to the direction in which the device is adapted to move or be propelled over the ground surface.

The plenum head 12 has a compressed air inlet 13 mounted approximately centrally along its length, and outlets of reduced size which effects an increase in the velocity of the air passing therethrough. The outlets direct the air at an angle downwardly beneath the apparatus against the surface and particularly the particulate matter to be dislodged from the synthetic grass surface and entrains the dislodged material in the air flow. The manifold 12 is substantially rectangular when viewed from above. The manifold 12 has a pair of side rails 16 which are located adjacent to ground surface when the apparatus is in use. The side rails 16 also mount the plenum head 1 1. Additionally, the broom 15 is mounted relative to the side rails 16 but normally an upstanding armature (not shown) is mounted on each side rail 16 and extending upwardly into the cavity defined by the manifold 12 in order to mount the broom 16.

Normally, there is a forward cross member 17 and a rear cross member 18 to brace the manifold 12 and to maintain the rail members 16 in a spaced apart condition. Each of the forward 17 and rear 18 cross members are spaced from the terminal end of the rail members 16.

Elongate cylindrical roller members 19 are provided in front of the forward cross member 17 and behind the rear cross member 18, The ground engaging rollers 19 are mounted between the rail members 19. The rollers 19 support the weight of the manifold 12 and the components of the apparatus mounted to the plenum head 11.

The manifold 12 has a forward portion 20 which, is at least partially arcuate. Preferably, the broom is mounted in this forward portion. The manifold also has a top wall extending rearwardly of the arcuate forward portion, a rear wall and a pair of sidewalls. Normally the port through which the lightweight matter is exhausted will be located through either the top wali or the rear wall of the manifold.

The apparatus of the invention is also provided with a cylindrical broom 15 extending substantially across the cavity which the manifold 12 defines, The broom 15 may be mounted either in front of the pleaded head 11 behind the plenum head 11 with the forward position preferred. The broom 15 acts to either dislodge or breakup larger detritus or it may remove leaves or the like of which have come to rest on the surface prior to the plenum head cleaning the surface.

The combination of the broom 15 and the compressed gas cleans the surface and particulate material within the surface more efficiently and effectively than the prior art methods. The upper region of the manifold 12 generally incorporates the outlet port 14 through which the lightweight matter is exhausted. The port 14 may be simply an opening about which a deflector or similar means can be arranged if necessary to prevent the coarse, particulate matter being sucked therethrough. The port 14 will generally communicate with a separation system.

A preferred embodiment of the air jet manifold used according to the present invention is illustrated in Figures 4 to 6. The air jet manifold includes a manifold pipe 50 which extends substantially horizontally across the housing. The manifold pipe is attached to housing using a stud 51 at either end and air flows into the manifold pipe through a T-connection 52 approximately halfway along the width of the pipe. The stud 51 is welded 91 into each end of the manifold pipe 50.

As best illustrated in Figure 6, spaced across the width of the manifold pipe 50 are a number of nozzles 54 in order to direct the air at the surface to be cleaned. The nozzles are oriented at approximately 45° and can be directed either forwardly or rearwardly.

Illustrated in Figure 7 is a drive brush housing roller mounting mechanism. As can be seen in figure 7, the arrangement of the roller is such that the roller is mounted through the housing wall 55 on a shaft 56. The shaft 56 which is illustrated in Figure 8 is surrounded by a shell 57 which can rotate about the shaft via the provision of a bearing 58 provided at either end. This allows the brush to rotate freely about the shaft.

Illustrated in Figure 9 is a detailed view of the end of the shaft showing a stepped profile which decreases in diameter from the shaft 56 itself, to an intermediate portion 59 and finally to a mounting thickness 60 with a hollow end 92.

¹ A preferred form of the driven brush assembly is illustrated in Figure

10 with a preferred brush core illustrated in Figure 11. The brush core 61 is mounted directly through the housing wall 55 or in a separate casing end 63 about a stub shaft 62 illustrated more clearly in Figure 11.

The driven brush 64 can rotate about the stub axle 62 through the provision of a bearing at either end of the brush 65. As illustrated in Figure 10, the brush itself has the form of a helical brush member, wound about the brush core illustrated in Figure 11. Also illustrated in Figure 11 is the preferred method for attaching the stub axle 62 to the hollow cylindrical brush core 61 by welding 66 radially extending attachment plates to an inner surface of the brush core 61 at either end of the brush core 61. The general arrangement of the housing 70 according to a particularly preferred embodiment is illustrated in figure 12. The housing includes a removal duct

71 for removal of any material collected. The removal duct 71 includes an attachment mechanism 72 for an air supply in order to create a ventuπ effect in the removal duct 71.

The housing also includes attachment mechanism for the air supply 73 for the jet manifold.

The housing illustrated is mounted on a pah' of attachment amis 74 on either lateral side of the housing 70. Both attachment arms 74 on either side have a common pivot bush 75 which is then connected to the vehicle supporting the apparatus.

At a lower portion of both the front and the rear of the housing, a roller 76 is provided and which extends across the width of the housing 70. Further, a Teflon or similar strip 77 is provided extending down either side of the housing 70 in order to assist with moving the housing along a ground surface. The Teflon strip 77 is provided on an underside of the housing endplate 80 which extends further laterally than the remainder of trie housing 70

Located at either end externally of the housing 70 is an adjustment/seal plate 78 which can be moved upwardly or downwardly to change the separation distance of the brushes within the remainder of the housing. The adjustment/seal plate

78 is covered using a cover plate 79 to limit the exposure of the adjustment/seal plate

78 to the elements. illustrated in Figure 14 is a preferred configuration of the apparatus of the present invention showing particularly the position of the preferred two brushes relative to the air injection manifold 50 and the drive mechanism 90.

As mentioned previously, the forward brush in the housing 70 is a driven brush 64 and the rearward brush is the drive brush 81. The interaction between the driven brush 64 and the drive brush 81 occurs through a drive arrangement which is illustrated schematically in figure 15. This drive arrangement can be directly overlaid onto figure 14.

In the drive arrangement, the drive sprocket 82 and three driven sprocket 83 are connected through the use of three idler sprockets 84 and a pair of drive belts 85 and 86. The first drive built 85 extends forwardly over the upper item sprocket down to the lower white or sprocket forwardly about the middle item sprocket and then rearwardly to the drive sprocket 82. The second drive belt 86 connects the middle item sprocket with the driven sprocket of the driven brush 64.

In the present specification and claims (if any), the word "comprising" and its derivatives including "comprises" and "comprise" include each of the stated integers but does not exclude the inclusion of one or more further integers.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearance of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more combinations.

In compliance with the statute, the invention has been described in language more or less specific to structural or methodical features. It is to be understood that the invention is not limited to specific features shown or described since the means herein described comprises preferred forms of putting the invention into effect, the invention is, therefore, claimed in any of its forms or modifications within the proper scope bf the appended claims (if any) appropriately interpreted by those skilled in me art. '

Claims

The Claims defining the Invention are as follows:

1. An apparatus for cleaning a synthetic grass surface, the apparatus comprising a elongate plenum head and a housing, the plenum head disposed within the housing and having a compressed air inlet and a plurality of air outlets spaced therealong through which air can be expelled against the synthetic grass surface for dislodgement of coarse and fine particulate material and to entrain the dislodged particulate material into the housing, said housing including an outlet located in an upper region of the housing for expelling the fine particulate material, and an outlet in a lower region of the housing for distributing the coarse particulate material back to the synthetic grass surface, and at least one elongate broom means mounted substantially parallel to the plenum head to contact the surface to be cleaned.

2. An apparatus for cleaning a synthetic grass surface according to claim 1 wherein the plenum head is an elongate member oriented substantially horizontally.

3. An apparatus for cleaning a synthetic grass surface according to claim 1 or claim 2 wherein the plenum head has at least one compressed air inlet mounted approximately centrally along its length, and a plurality of outlets of relatively reduced size which effect an increase in the velocity of the air passing therethrough.

4. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the outlets are oriented at an angle of between 30° and 75°, with respect to the synthetic grass surface.

5. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the plenum arm is mounted using a height adjustment means to adjust the separation of the outlets from the surface.

6. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the at least one broom is mounted relative to the side of the housing using an upstanding armature to mount the broom in an adjustable manner so that the height of the broom can be varied.

7. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims further including at least one elongate cylindrical roller is provided in a forward portion of the housing to at least partially support the weight of the housing.

8. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein a pair of slide members are provided, one on each side of the housing.

9. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the housing has a forward portion which is at least partially arcuate with at least one broom member mounted in this forward portion.

10. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein a further broom member is provided in a rear portion of the housing.

11. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the at least one broom member is cylindrical and extends substantially across the housing.

12. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein at least one the broom members is a powered broom.

13. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein a pair of brooms are provided, one being a drive broom and the second being a driven broom.

14. An apparatus for cleaning a synthetic grass surface according to claim 13 wherein the pair of brooms are interconnected using a drive mechanism and one or more drive belts.

15. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims further including one or more baffle plates arranged to partially enshroud the plenum arm member to prevent the coarse particulate matter from being carried into the port and to direct the coarse particulate matter back onto the surface from which it has previously been uplifted.

16. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims further including a deflector located in the region of the outlet from the housing.

17. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims further including an arrangement for separating the fine particulate material and removing it from the air.

18. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the compressed air is supplied to the surface to be cleaned at a relatively low volume, but at a relatively high pressure.

19. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the outlet from the housing has a compressed air inlet located therein in order to create a venturi effect in the outlet.

20. An apparatus for cleaning a synthetic grass surface according to any one of the preceding claims wherein the apparatus is included on a self propelled machine.