GB2306306A

GB2306306A - Brush mechanism for artificial play surfaces

Info

Publication number: GB2306306A
Application number: GB9522033A
Authority: GB
Inventors: Charles Clifford Seag Lawrence; Mark Anthony Keal
Original assignee: CHARLES LAWRENCE GROUP PLC
Current assignee: CHARLES LAWRENCE GROUP PLC
Priority date: 1995-10-20
Filing date: 1995-10-20
Publication date: 1997-05-07
Anticipated expiration: 2015-10-20
Also published as: GB9522033D0; GB2306306B

Abstract

A play surface brushing apparatus for providing a multi-directional brushing action to a particulate-filled artificial play or sports surface comprises at least two brush units 43, 44, 45 each adapted to provide a brushing action of the play surface in different directions in the plane of the surface to be brushed. In one arrangement, the apparatus includes at least two brush units 43, 44, 45 adapted to rotate simultaneously, in a brushing plane, about a first and a second axis of rotation substantially orthogonal to the brushing plane. In a second arrangement, (Figs 3 and 4) at least two substantially cylindrical brushes are mounted on a frame such that their axes are substantially parallel to one another. Drive means rotate the brushes in opposite directions. The apparatus is preferably towed and suspended behind a suitable tractor unit to provide a levelling, compaction and maintenance function on the play surface.

Description

BRUSH MECHANISM FOR ARTIFICIAL PLAY SURFACES The present invention relates to equipment for the maintenance, rejuvenation or other treatment of, for example, artificial play areas, and in particular to equipment for general treatment of play surfaces which treatment includes a brushing action on the play surface.

A typical surface to be treated may comprise an artificial turf which is laid onto, and embedded or infilled with, a particulate ballast such as sand. Artificial turfs which include a sheet of upstanding tufts of synthetic fibres are well known in the art and it is commonplace for the fibres to be embedded or infilled with a fine sand or other particulate matrix which assists in maintaining a quality play surface having appropriate impact characteristics. Such surfaces are often used for synthetic tennis courts, bowling greens and other playing fields.

From time to time, it is necessary to rejuvenate or renovate the play surface by extracting the sand or other particulate matter, and infilling the synthetic turf with a fresh layer of sand, or with the original sand which has been cleaned and/or filtered. Such renovation apparatus has been previously described, for example, in PCT applications, publication numbers WO 92/20272 and WO 95/06781.

To restore or initially lay the surface, it is particularly important to install the infill sand in a regular and even manner across and throughout the turf. This is typically achieved, after laying the fresh sand onto the artificial turf, by brushing with an elongate linear brush with downwardly extending bristles mounted onto a vehicle such that the long axis of the brush extends transversely to the direction of the travel of the vehicle over the surface being treated. A wide stripe of play surface can thus be brushed at any one time, but in order to obtain a good quality, even depth of infilled sand, it is usually necessary to make several passes along each part of the play surface, preferably in different directions.

The term "play surface" will be used throughout the present specification to encompass all sports, recreational, all-weather and children's play area surfaces which require a brushing operation for the purpose of maintenance, renovation or installation. The operations may include installation, levelling and compaction of an infill particulate material.

It is an object of the present invention to provide brushes which achieve a more efficient brushing of the surface, in order that a multidirectional brushing action can be effected with only a single pass of a vehicle conveying such brushes.

It is a further object of the invention to provide brushes which achieve a more controlled and even distribution of particulate matter over and/or throughout the play surface.

According to one aspect, the present invention provides a play surface brushing apparatus for providing a multi-directional brushing action to a surface, comprising at least two brush units adapted to provide simultaneous brushing action of the play surface in different directions in the plane of the surface to be brushed.

According to another aspect, the present invention provides a play surface brushing apparatus which has at least two brush units adapted to rotate simultaneously, in a brushing plane, about a first and a second axis of rotation substantially orthogonal to the brushing plane.

According to a further aspect, the present invention provides a play surface brushing apparatus which comprises: a support frame; at least two substantially cylindrical brushes mounted on the frame such that the long axes of the brushes are substantially parallel to one another; and drive means for rotating the first brush about its long axis in a first direction and the second brush about its axis in a second direction opposite to the first direction.

Embodiments of the present invention will now be described in detail and with reference to the accompanying drawings in which: Figure 1 shows a perspective view of multi-directional brushing apparatus according to a first embodiment of the present invention using a rotary member with a number of rotating satellite brush units; Figure 2 shows a plan view of the underside of the apparatus of figure 1; Figure 3 shows a cross-sectional side view of the apparatus of figure 2 along section A-A; Figure 4 shows a schematic perspective view of two brush units of a multi-directional brushing apparatus according to a second embodiment of the present invention using counter-rotating cylindrical brush units, useful for the purpose of illustrating the principles thereof;; Figure 5 shows a side view of a multi-directional brushing apparatus using the counter-rotating cylindrical brush units of figure 4.

With reference to figures 1, 2 and 3, a presently preferred embodiment of the present invention will now be described.

A multi-directional play surface brushing apparatus 5 comprises a substantially cylindrical housing having a circular cover plate 10 and a skirt 12 extending downwardly from the peripheral edge of the cover plate 10, thereby forming a cylindrical cavity having an open end facing downward. Mounted onto the top surface of the cover plate 10 are pivot brackets 14,16 by which the cover plate is coupled to a pair of support arms 15,17 for connection to a suitable vehicle, such as a small tractor unit (not shown). The brushing apparatus 5 is thereby suspended, at a suitable height, in cantilever fashion from supports on the tractor well known in the art. The pivoting brackets 14,16 ensure that the apparatus 5 is presented parallel with the play surface upon which it is to operate, while the tractor or other vehicle provides load bearing support for the apparatus 5.

Preferably, the skirt is fabricated from a suitable light weight plastics material which is not required to support the apparatus weight.

Mounted centrally on the cover plate 10 is a motor housing 20 which covers an hydraulic motor 21 (see figure 3) with hydraulic line feed pipes 22 passing thereto. The hydraulic motor is coupled by way of drive shaft 23 to a brush unit support member 30 which is rotatable about the longitudinal and vertical axis of the drive shaft 23. The drive shaft may include a clutch and/or gearbox mechanism well known in the art to enable control of the speed of rotation of the support member 30.

In the presently preferred embodiment, the brush unit support member 30 comprises a hub 32 with three equally spaced, radially extending arms 33, 34 and 35. Each arm includes a pivot 36, 37, 38 to which are respectively attached three "satellite" brush units 43, 44 and 45.

Each brush unit 43, 44, 45 may thereby rotate freely about a vertical axis defined by its respective pivot 36, 37, 38.

In the presently preferred embodiment, each brush unit 43, 44, 45 comprises a set of four linear brushes 50-53 with downwardly extending bristles 54, each linear brush 50-53 extending radially outward from the pivots 36, 37, 38.

Although the hydraulic motor 21 is adapted to drive only the support member 30 about its axis, the free-running nature of pivots 36, 37, 38 is such that the satellite brushes tend to self-rotate by virtue of the friction of the bristles with a play surface over which the brushing apparatus travels.

In use, the multi-directional brushing apparatus is coupled up to the tractor unit via support arms 15,17, and suspended at an appropriate height such that the bristles 54 of the brushes 50-53 come into sweeping engagement with the play surface. The hydraulic motor 21 is coupled up to a suitable hydraulic pump or power output of the tractor unit by way of lines 22, and the apparatus is conveyed in a forward direction. The combination of the forward motion of the tractor unit and the rotational motion of the support arm 30 has been found to provide a high quality, multi-directional brushing action ideally suited to yielding a controlled and even distribution of infill particulates to a play surface, and a desired degree of compaction.

It will be understood that a number of modifications may be made to the apparatus of figures 1, 2 and 3. The support member 30 may have a different number of arms than three, and the arms need not be equally radially spaced. The arms need not be radially arranged, providing that the axis of rotation exemplified by the drive shaft 23, and the axis of rotation of a satellite brush unit exemplified in pivot 36, are not coincident.

Brush units 43, 44 and 45 may be provided with any number of linear brushes suitably arranged, or indeed as a single circular brush with downwardly extending bristles.

Brush units 43, 44, and 45 may be individually powered to rotate about their respective pivots 36, 37 and 38, rather than being freerunning, using a suitable separate motor or satellite drive shaft arrangement coupled to the main drive shaft 23. However, this is a less desirable alternative insofar as it adds considerably to the cost, complexity and weight of the apparatus. For normal purposes, it has been found to be unnecessary as indicated above.

The motor 21 need not be hydraulically powered. An electric motor or other drive system could be used.

The gauge of the brush units (ie. the width w of the brush unit relative to the forward direction of travel v of the apparatus, indicated on figure 2) may be any suitable size, taking into account that for slow speeds of rotation, there is preferably a continuous overlap in the paths swept out by each of the brush units 43, 44, 45 regardless of the rotational position of the support member 30. Thus, appropriate lengths of arms 33, 34 and 35 must be made for any given brush unit gauge.

In the presently preferred embodiment, the arm lengths 33, 34, 35 (ie. distance between pivots 36, 37, 38 and drive shaft 23) is approximately 0.4 m; the brush unit gauge w at its maximum value (ie.

with the brush at right angles to the direction of travel) is approximately 0.6 m; the overall width y of the apparatus 5 is approximately 1.4 m; the approximate speed of rotation of the support member 30 is between 30 and 50 r.p.m. and the.optimum forward velocity of the tractor unit is between 0 and 1.6 km/h.

Although the embodiment described is shown adapted for suspension from and behind a suitable tractor unit, it will be understood that the brushing apparatus 5 could readily be provided with independent wheeled support. Such independent wheeled support would preferably be height adjustable to enable the brush units to be positioned accurately at the appropriate height above the surface to be treated. Such an arrangement is described in greater detail with respect to the apparatus of figure 5.

With reference to figure 4 there is shown the configuration of two cylindrical brushes of a multi-directional play surface brushing apparatus 120 according to another aspect of the present invention.

In this arrangement, at least two elongate cylindrical brushes 102, 104 are rotatably mounted on a frame 110. The axis of rotation of each brush is substantially parallel to the play surface to be brushed, and the axes are substantially parallel to one another.

The frame 110 includes support arms 115 which may be connected to a suitable tractor unit (not shown) in similar manner to that described to brushing apparatus 5. The brushing apparatus 120 may thereby be towed in a direction indicated by arrow A behind the tractor unit such that brush 102 is the foremost or leading brush, and brush 104 is the rearmost or trailing brush.

The brushes are provided with drive means (not shown) to rotate them about their respective axes. Such drive means is preferably an hydraulic motor and gearbox arrangement similar to that described with respect to brushing apparatus 5, or may also be any other suitable motor arrangement, such as electric. To provide an optimum brushing action of the play surface, the motor is adapted to drive the leading brush in a clockwise direction as viewed from the right side of the apparatus (arrow C in figure 4), and to drive the trailing brush in an anticlockwise direction with respect to the same viewpoint (arrow D in figure 4).

In the preferred embodiment, the direction and speed of rotation of the leading brush are such that the bristles of the brush are driven backwards (arrow C) over the play surface faster than the forward motion (arrow A) of the apparatus 120 over the play surface, so that there is a net brushing action in a rearward direction (arrow B). Conversely, the speed and direction of the trailing brush are such that the bristles of the brush are driven forwards (arrow D) over the play surface faster than the forward motion (arrow A) of the apparatus 120 over the play surface, so that there is a net brushing action in a forward direction (arrow B').

In the presently preferred embodiment, the cylindrical brush lengths are approximately 1.2 m; the approximate speed of rotation of the leading brush is 300 r.p.m.; the approximate speed of rotation of the trailing brush is 300 r.p.m.; and the optimum forward velocity of the tractor unit is between 0 and 2.75 km/h.

Figure 5 illustrates a further aspect of the multi-directional brush apparatus. Brushing apparatus 120 includes support arms 115 which include a coupling (not shown) for attachment to a tractor unit which supports the leading end of the brushing apparatus. Behind the trailing brush 104 there is provided a height adjustable wheeled support member 125. Wheeled support member 125 preferably comprises a wheel 130 mounted on the lower end of a piston 128 which is telescopically mounted within a cylinder 127. The telescopic extension of the piston 128 out of cylinder 127 may be controlled by a suitable pneumatic or hydraulic piston arrangement 135 well known in the art, to maintain correct height of the brushes on the play surface and also automatically maintain correct downward force of the bristles of the brushes onto the play surface. In this manner, the vigorousness of the brushing action can be adjusted via a suitable pressure adjustment mechanism in the hydraulic or pneumatic piston 135. Alternatively, the piston 128 and cylinder 127 arrangement may be provided as simple telescopic sections, with a mechanical locking arrangement with bolts or the like.

It will be understood that a suitable height adjustable wheeled support can also be applied to the embodiment of figures 1 to 3.

Although the multi-directional brushing apparatus herein described is suitable for towing behind a conventional tractor unit, it is also envisaged that the apparatus may be integrated with suitable play surface renovation equipment, such as those described in WO 92/20272 and WO 95/06781.

Claims

1. A play surface brushing apparatus for providing a multi-directional brushing action to a play surface, comprising at least two brush units adapted to provide simultaneous brushing action of the play surface in different directions in the plane of the surface to be brushed.

2. A play surface brushing apparatus according to claim 1 in which each of the at least two brush units is adapted to rotate simultaneously, in a brushing plane, about a first and a second axis of rotation substantially orthogonal to the brushing plane.

3. A play surface brushing apparatus according to claim 2 including a first member rotatable about a main pivot corresponding to said first axis of rotation and at least two satellite members each rotatably connected to the first member via a respective satellite pivot corresponding to respective second axes of rotation, each brush unit mounted on one of said satellite members.

4. A play surface brushing apparatus according to claim 3 in which the first member comprises a plurality of arms extending radially outward from the main pivot, with at least one satellite member coupled to each arm.

5. A play surface brushing apparatus according to claim 4 in which the number of arms is three.

6. A play surface brushing apparatus according to any one of claims 2 to 5 in which each brush unit comprises a plurality of brushes each extending substantially radially outward from its respective second axis of rotation.

7. A play surface brushing apparatus according to claim 6 in which each brush unit comprises four brushes extending outward from its respective second axis of rotation.

8. A play surface brushing apparatus according to claim 6 or claim 7 in which each brush extends radially outward from the respective second axis of rotation a length sufficient to ensure continuous overlap of different paths swept out by each brush unit.

9. A play surface brushing apparatus according to any one of claims 2 to 8 further including drive means to rotate the first member about the main pivot.

10. A play surface brushing apparatus according to claim 9 in which the satellite members are each free-running about their respective satellite pivots.

11. A play surface brushing apparatus according to claim 9 in which the drive means is a hydraulic motor.

12. A play surface brushing apparatus according to any preceding claim further including connecting means for connecting the apparatus to a play surface renovation apparatus.

13. A play surface brushing apparatus according to claim 1 comprising: a support frame; at least two substantially cylindrical brushes mounted on the frame such that the long axes of the brushes are substantially parallel to one another; drive means for rotating the first brush about its long axis in a first direction and the second brush about its axis in a second direction opposite to the first direction.

14. A play surface brushing apparatus according to claim 12 further including propulsion means for conveying the brushes over the play surface such that the long axes of the brushes are substantially orthogonal to the direction of travel of the apparatus.

15. A play surface brushing apparatus according to claim 13 in which the first brush is a leading brush and the second brush is a trailing brush, the drive means and propulsion means are jointly adapted to rotate the leading brush at a speed and in a direction such that the brushing action is in a direction opposite to that of the direction of travel of the apparatus, and adapted to rotate the trailing brush at a speed and direction such that the brushing action is in the same direction as the direction of travel of the apparatus.

16. A play surface brushing apparatus according to any preceding claim further including means for suspending the brushing apparatus at a predetermined height above a play surface.

17. A play surface brushing apparatus according to claim 16 in which the means for suspending the brushing apparatus is adjustable for different heights.

18. A play surface brushing apparatus substantially as described herein with reference to the accompanying drawings.