GB2543301A - Sports pitch divider net deployment apparatus - Google Patents

Abstract

A pair of nets 3, 3' are suspended across a sports pitch between upper and lower cables 4, 5 supported by opposed posts 7, each upper cable 4 passing over a wheel 13 mounted at a distal end of an arm 9 on which the respective net is stored. The cables are stored on twin winch drums independently operated by separate cranks 23 which are arranged for rotation about preferably collinear or parallel axes so that the swept circle defined by the rotation of each crank handle contains the rotation axis of the respective other crank. The wheel reduces friction on the upper cable to assist in simultaneous operation of the winches. Each winch may be braked by a restraint mechanism 30 comprising a ratchet and friction clutch, the clutch being engageable and disengageable by rotation of the crank which is moved to an idle position to allow the drum to freewheel.

Description

Sports pitch divider net deployment apparatus

This invention relates to net deployment and tensioning systems for use on sports pitches, particularly but not exclusively for dividing the pitch into multiple smaller pitches for separate use.

In this specification, a sports pitch is any indoor or outdoor area comprising a surface on which a sport is played, including football pitches, tennis courts, and the like.

Indoor and outdoor sports pitches are commonly divided by one or more nets to define multiple, smaller pitches so that multiple ball, racquet or other games may be played at the same time when the full size pitch is not required. Each divider net is suspended from a cable supported between posts on opposite sides of the pitch and tensioned by a winch. Usually a steel cable is provided to withstand the substantial tension force applied by the winch.

Conveniently, the cable may be arranged to run through a tubular, horizontal arm which extends for a short distance from the post, so that the net is drawn onto the arm as the cable is retracted, leaving the net neatly hanging from the arm ready for the next use.

It is also possible to suspend the net from a pair of cables tensioned by separate winches, as disclosed by GB 2448989 A. Alternatively, the net may be suspended from a tensioned cable and then pulled tight by means of further tensioning cables passing over pulleys, as disclosed by GB 2458277 A.

In order to provide more compact storage when a divider net is not in use, it is known co divide the net into two halves, each half being supported by a separate cable supported on a post on one side of the pitch. To deploy the divider net, the two cable ends are pulled out and clipped together in the centre of the pitch and then tensioned by winches mounted on the respective posts to suspend the two portions of the net end-to-end to form a single barrier.

It is also known to arrange a pair of tensioned steel cables in vertically spaced parallel relation to support both the upper and tower edges of a divider net so as to retain the net in a fixed position during play. For example, GB 2324474 A discloses an arrangement of nets supported by upper and lower cables which are tensioned by winches driven by a common motor.

Net deployment or tensioning systems may also be used on sports pitches for other purposes, such as for tensioning a tennis net across the centre of the court. For example, GB197200 A discloses a winch for use in supporting a tennis net and comprising double coaxial drums rotated by a single worm wheel arranged between them.

Where a net is supported between upper and lower cables, it is desirable for the upper and lower cable winch drums to be operable independently of one another in order to correctly tension each of the cables while accommodating small differences in cable length or lift rate, for example, due to the uneven or multiple layering of each cable on its respective winch drum.

This can be accomplished by providing a motorised drive for each of the winches. For example, JP H03-151991A discloses a pitch divider net apparatus with twin winch drums driven by a common motor via clutches and brakes which are independently operated to tension each of the cables.

However, for a hand cranked system (which is simpler and hence often preferred) the use of two individual winches with separate handles for reeling in the upper and lower cables can be awkward for a single operator and so may increase the time required to deploy and, particularly, to recover the net.

If the operator needs to use both hands to operate each winch to relieve cable tension until the cable is sufficiently slack to unclip the cable end prior to reeling in the cable, then the winches will need to be operated alternately rather than simultaneously.

It is possible of course to provide a ratchet or other restraining mechanism which can be moved to a disengaged position so that the cable tension is restrained only by the operator's pressure on the winch handle, allowing the operator to unwind the cable from the drum using only one hand. However, the simultaneous operation of two winches equipped with such a mechanism would be particularly difficult for a single operator. Moreover, a tensioned steel cable extending over the width of a sports pitch will store a substantial amount of energy proportionate to its length, which means that such arrangements would be potentially hazardous for the operator. This is particularly the case if the winch has a relatively high lift rate, since the cable tension may rotate the crank with high force if the handle is inadvertently released by the operator while the ratchet is disengaged. For this reason, hand cranked winches for use in deploying nets on a full size pitch typically have a relatively low lift rate per crank turn and are slow in operation.

It is a general objective of the present invention to provide an apparatus for deploying a net on a sports pitch which is convenient and effective in use.

Accordingly in its various aspects the invention provides a winch assembly, a net deployment apparatus, and an installation comprising two such apparatuses as defined in the claims.

In a first aspect, a winch assembly for use in deploying a net on a sports pitch comprises a pair of winches, each winch including a drum for receiving a respective one of a pair of upper and lower cables in a retracted position of the net, a restraint having an engaged condition and a disengaged condition, and a crank rotatable about a first axis to drive the drum in rotation independently of the drum of the respective other winch, the crank including a handle. Each restraint is arranged in the engaged condition to prevent the respective cable from unreeling from its drum when under strain in the extended position of the net, and in the disengaged condition to allow the respective cable to be unreeled from its drum. Each handle has a nominal second axis defined by a line parallel with the first axis of its respective crank and passing through a central point of the handle, each second axis describing a swept circle in a plane normal to the first axis of the respective crank as the handle of the crank is rotated about the first axis of the crank to drive its respective drum in rotation. The swept circle contains the first axis of the crank of the respective other winch.

In a second aspect, a winch assembly for use in deploying a net on a sports pitch includes at least a first winch, a post, the first winch being mounted on the post, and an arm extending outwardly from an upper end region of the post, the post being arranged to support an upper cable so that it extends along the arm in use. The first winch has a drum for receiving the upper cable in a retracted position of the net, and a crank rotatable about a first axis to drive the drum in rotation, the crank including a handle. The assembly further includes a wheel mounted for rotation at a distal end of the arm to support the upper cable as it passes over the wheel during operation of the first winch, and a plurality of suspension rings for supporting an upper edge region of the net when the suspension rings are threaded onto the cable, the wheel being arranged to pass through the suspension rings so that the suspension rings can slide along the arm as the net is returned to the retracted position so as to suspend the net from the arm.

Further features and advantages will be apparent from the various illustrative embodiments of the invention which will now be described, purely by way of example and without limitation to the scope of the claims, and with reference to the accompanying drawings, in which:

Fig. 1 shows two net deployment apparatuses installed on either side of a sports pitch, each apparatus comprising a respective winch assembly including a winch unit mounted on a post, and showing the nets respectively in the extended position (3) and the retracted position (3'); Figs. 2A - 2D show one of the winch units respectively in oblique, front, side and top view;

Fig. 3 shows a variant of the winch unit;

Figs. 4A and 4B show the crank and restraint mechanism of the winch unit, with the crank respectively in the use condition (Fig. 4A) and the idle condition (Fig. 4B);

Fig. 5 is an enlarged view of detail A in Fig. 1 showing part of the net storage arm and upper cable wheel;

Fig. 6 is an exploded view of the drum assembly of the winch unit;

Fig. 7 is an exploded view of the restraint mechanism of the winch unit; and Fig. 8 is an enlarged exploded view of some of the components of Fig. 7.

Reference numerals appearing in more than one of the figures indicate the same or corresponding parts in each of them.

Referring to the figures, a pair of net deployment apparatuses 1 are arranged respectively on opposite sides of a sports pitch 2, each apparatus including a net 3, 3' and a pair of upper and lower cables 4, 5 arranged in vertically spaced relation to support respective upper and lower edge regions of the net in an extended position of the net (3).

Each apparatus further includes a respective winch assembly 6 comprising a winch module 20 mounted on a vertical post 7 whose lower end region is supported below the surface 8 of the pitch, e.g. in a concrete footing, and having a net storage arm 9 extending outwardly and generally horizontally towards the pitch from its upper end region 10. The post includes pulleys 11 which support the upper and lower cables so that the upper cable 4 extends along the net storage arm 9 in use; conveniently, the net storage arm is tubular so that the upper cable passes through it and exits through a hole in the post proximate the upper pulley 11 as shown, although it could alternatively be formed as a channel section or a solid bar. The net storage arm may be for example a heavy walled steel tube about 40mm in diameter and fixed rigidly to the post, with the post and winch components generally also being made from steel, although of course aluminium or other metal or non-metal materials may be used.

The winch module 20 includes a pair of winches 21 mounted in a common housing 29, each winch including a drum 22 for receiving a respective one of the cables in a retracted position of the net, and a crank 23 for driving the drum in rotation independently of the drum of the other winch, so that the winches can be manually operated to reel in the cables with the net being stored on the arm in its retracted position (3') as further explained below. The housing is preferably of similar width to the post 7 and is fixed to the post so that the cranks revolve on opposite sides of the post. Each drum may be arranged to hold, for example, about 35m of steel cable so that two assemblies can span the width of a full sized artificial pitch.

Each winch also includes a restraint 30 which acts as a brake on the drum, having an engaged condition and a disengaged condition.

In the disengaged condition, the restraint allows the drum to rotate or freewheel so that the respective cable can be unreeled as the user walks with its distal end out into the middle of the pitch. Each cable has a clip 12 at its distal end so that the user can connect it to the respective other cable in the centre of the pitch. After connecting together the two upper cables and two lower cables, the user can return to one of the winch assemblies and crank the winches to tension the cables. The user can then release the winch handles with each restraint in the engaged condition in which it prevents the respective cable from unreeling from its drum under strain. Each net can be left hanging from its storage arm 9 until the cables are tensioned, and then drawn out along the length of the cables until the two nets are arranged end to end with the cables holding them upright in the extended, use position (3).

Each crank 23 comprises an arm 24 with a handle 25 mounted at its distal end region and is rotatable on a shaft 37 about a first axis XI of the shaft at a proximal end region of the arm to drive the respective drum 22 in rotation via the shaft 37 and gears 26, 27 (Fig. 6) which are advantageously arranged to give a relatively high lift rate per crank turn. The handle has a nominal second axis X2 defined by a line parallel with the first axis XI of the respective crank and passing through a geometrically central point 28 of the handle. Conveniently as shown the handle may be mounted for rotation about the second axis and may also be geometrically aligned with the second axis, preferably defining a surface of rotation about the second axis.

When projected onto a plane normal to the first axis XI of its respective crank, preferably a common plane P normal to both first axes and mid-way between the two handles as shown, the second axis X2 of each handle describes a swept circle C in the plane P as the handle is rotated about the first axis XI of the crank to drive its respective drum in rotation. Preferably as shown the arms 24 are the same length so that the swept circles of the two cranks are of equal radius R. Preferably the crank arms are arranged to revolve in parallel spaced planes and the handles are oppositely directed and normal to said planes as shown, so as to be operable simultaneously by one person standing at the post.

It is found that where two winches are spaced apart in this configuration and operated independently by two cranks, even if the handles are conveniently positioned for operation by a single user, the varying cyclic movement patterns generated by the changing angular positions of the cranks poses a co-ordination problem which can make it difficult to operate both winches simultaneously. However, by arranging each swept circle C to contain the first axis XI of the crank of the respective other winch as shown, it is found that the user can co-ordinate the operation of the two cranks even when their relative angular positions vary. This makes it easy to operate the two winches independently and also simultaneously, even if the cranks are rotated at different speeds.

Preferably the first axes of the two cranks are collinear as shown in Figs. 2A - 2D. However, it is found that as long as the first axis of each crank lies within the swept circle defined by the second axis of the other crank, the user is able to co-ordinate the two cranks as if their axes were collinear. If the first axes are not collinear then they are preferably substantially parallel, in which case they are preferably separated by a distance less than half the average radius R of the swept circles, as shown in the example of Fig. 3, which makes it easier to co-ordinate the operation of the two cranks even when their relative angular positions vary.

Variations in torque reaction between the two winches may also make it counterintuitive and hence more difficult for a single user to co-ordinate the operation of both cranks simultaneously, particularly when the relative angular positions of the cranks vary. When the cables are uncoupled, the weight of the upper cable depending from the net storage arm imposes a relatively higher load than the lower cable which lies on the ground. In order to make the loads on the winches more equal, a wheel 13 is mounted for rotation at the distal end of the net storage arm to support the upper cable 4 and reduce friction as it passes over the wheel during operation of the respective winch. Preferably as shown the wheel 13 comprises a pulley wheel or sheave having a groove for receiving the cable. A plurality of suspension rings 14 are threaded onto the cable and connected to the upper edge region of the net to suspend the net from the cable, so that the upper cable 4 passes through the suspension rings, over the wheel 13 and through the tubular net storage arm 9 to the respective winch. The wheel 13 is arranged to pass through the suspension rings 14 so that the net can be drawn back along the cable and stored in its retracted position (3') by sliding the suspension rings over the wheel and along the net storage arm 9. The wheel 13 makes it easier to operate the winch for the upper cable and also helps to equalise the load on the twin winches so that it is more intuitive and so easier for a single user to co-ordinate the operation of both cranks simultaneously.

After retracting the net, the user must disengage the restraints on one of the winch modules in order to unreel and slacken the cables sufficiently to uncouple the clips 12 before reeling the cables back onto the drums. Advantageously, the crank of each winch may be arranged to be rotatable in a first direction D1 to engage the respective restraint and to reel the respective cable onto its drum, and in a second, opposite direction D2 to disengage the respective restraint and to unreel the cable from its drum. By arranging for each restraint to be engaged and disengaged in this way by rotation of the respective crank, it is possible (despite the substantial tension force which is required to support a cable across the width of a full size pitch) for a single user to operate the cranks of the two winches both safely and simultaneously, in the forward direction D1 to tension the cables and engage the restraints so that the handles can be released with the cables held in the strained condition, and also in the reverse direction D2 to simultaneously disengage the restraints and pay out the cables to relieve the strain. This also allows the winches to have a relatively high lift rate per crank turn, so that it takes less time to deploy and retrieve the nets, while substantially removing the risk of injury by rapid rotation of the cranks in the event that a crank handle is inadvertently released while the cables are under tension.

Fig. 7 illustrates one way of achieving this by means of a restraint mechanism 30 of generally known type, combining a ratchet wheel 31 and pawl 32 with a friction clutch comprising friction plates 33 rotatably mounted with the ratchet wheel on a bush 34 to rotate freely about the shaft 37. The friction plates 33 frictionally engage the ratchet wheel when the plates 33 and ratchet wheel 31 are pressed together between opposed plates 35,36. The friction plates 33 may be made from aluminium to obtain a higher coefficient of friction with the steel ratchet wheel and plates 35, 36, although other suitable friction materials may be selected as known in the art. The plate 35 is pinned to the shaft 37 defining the first axis XI so that it rotates together with the shaft, while the plate 36 comprises a pressure control element with a threaded bore which is mounted for rotation about the first axis XI on a screw thread 51 formed on the shaft 37. (Of course, plate 35 could alternatively engage a square profile on the shaft.)

The screw thread 51 defines a short axial displacement of the plate 36 sufficient to frictionally engage and disengage the ratchet wheel with the plate 35 as the plate 36 rotates through a small angular range between limit positions defined by the abutment of an arm 38 against the walls of a recess 39 in a housing 40 which is fixed to the plate 36 by roll pins 41. (Alternatively, plate 36 and housing 40 could be welded together or made as a unitary part.) It will be noted that the arm 38 is rotated through 180° from the illustrated postion before assembly. The arm 38 extends from a body 42 with a splined bore 43 and is rotationally fixed to the shaft 37 by a splined connector 44 which is housed in the bore and fits onto the half-round distal end of the shaft, the splines permitting the housing to be adjusted during assembly to the correct position on the screw thread 51. The body 42 has a small projection 45 opposite the arm 38, which engages a sprung ball assembly 46 inserted into a transverse bore 47 of the housing 40 to form a detent mechanism. In order to rotate the housing 40 on the screw thread 51 between the engaged and disengaged positions of the restraint, it is necessary to apply sufficient torque to the housing 40 relative to the shaft 37 to overcome the spring force of the sprung ball assembly 46. The projection 45 depresses the ball against its spring so that the ball moves across the projection with a sensible and audible click, indicating to the user that the restraint has been operated as the crank is rotated through its small angular range of freedom relative to the shaft.

The pawl is arranged to allow the ratchet wheel to rotate in the forward direction D1 but not in the reverse direction D2. When the crank is rotated in the forward direction Dl, the ratchet wheel is frictionally engaged to rotate together with the shaft so that when the handle is released the pawl prevents the drum from rotating in the reverse direction and holds the cable in the strained condition. When the crank is rotated in the reverse direction D2, the ratchet wheel is frictionally decoupled from the shaft so that the shaft can rotate while the ratchet wheel remains static.

Advantageously, the crank 23 may comprise a mass sufficient to re-engage the restraint from its disengaged condition by inertial reaction of the crank to rotation of the respective drum when its handle 25 is released by the user in a maximally strained condition of the cable. The mass may be unbalanced with respect to the first axis of the crank, comprising for example a solid bar forming the crank arm 24 as shown, so that it applies a moment at the first axis XI when moved away from a vertical position.

In normal operation, the user will rotate the handle to reel or unreel the cable to the desired tension, and then release the handle leaving the restraint in the engaged condition (if the crank has been rotated in the forward direction Dl to tension the cable) or in the disengaged condition (if the crank has been rotated in the reverse direction D2 to leave the cable in a slack condition).

Even while the user is rotating the crank in the reverse direction, as long as the cable is under tension it will tend to rotate the drum and so move the restraint to the engaged condition whenever the rotation of the crank is paused. However, in case the restraint should be in the disengaged condition and the cable still under strain when the user releases the handle, the acceleration of the drum and shaft acting against the intertial mass of the crank is sufficient to overcome the sprung ball detent mechanism 45,46 and rotate the housing 40 on the screw thread 51 of shaft 37 to the engaged condition of the restraint so that the rotation of the shaft in the reverse direction D2 is braked against the ratchet wheel restrained by the pawl.

Advantageously, to make it possible for the user to pull the end of the cable out onto the pitch when deploying the net, the crank of each winch may be adjustable between a use condition in which the crank is rotationally engaged (via gears 26,27) with the respective drum 22 and restraint mechanism and an idle condition in which the crank is rotationally disengaged from the drum and restraint mechanism, so that the drum can rotate freely without engaging the restraint when the crank is in the idle condition. This can be achieved as shown by mounting the crank arm 24 on a spindle 48 which extends along the first axis XI from a plate 49 which is fixed by screws to the housing 40. A pair of studs 50 extend from the outer face of the plate 49 on either side of the spindle. The crank arm 24 is free to move both axially and rotationally on the spindle, and in the use condition (Fig. 4A) is engaged in rotation with the studs 50 and hence shaft 37. The crank is moved to the idle condition by pulling the arm 24 away from the winch housing in the direction of the arrow (Fig. 4B), disengaging the crank from the studs so that it can rotate freely on the spindle.

In summary, a preferred embodiment provides a pair of nets which are suspended across a sports pitch between upper and lower cables supported by opposed posts, each upper cable passing over a wheel mounted at a distal end of an arm on which the respective net is stored. The cables are stored on twin winch drums independently operated by separate cranks which are arranged for rotation about preferably collinear or parallel axes so that the swept circle defined by the rotation of each crank handle contains the rotation axis of the respective other crank, making it easier to operate both winches simultaneously. The wheel reduces friction on the upper cable to assist in simultaneous operation of the winches. Each winch may be braked by a restraint mechanism comprising a ratchet and friction clutch, the clutch being engageable and disengageable by rotation of the crank which is moved to an idle position to allow the drum to freewheel.

The restraint could comprise any suitable mechanism which is selectively engageable and disengageable, which is to say, it may be selectively engaged (i.e. applied) to prevent the cable from unreeling from the drum and disengaged (i.e. released) to allow the cable to be unreeled from the drum.

This may be accomplished by a friction clutch, which may be engaged and disengaged by movement of a pressure control element along the first axis of the respective crank, the pressure control element being mounted for rotation on a screw thread about the first axis XI as in the illustrated embodiment. In alternative embodiments, it could be accomplished by a detent or other arrangement, for example, by moving a pawl and ratchet wheel, interlocking crown gears or other respective parts in and out of contact, or by altering pressure or friction or otherwise changng the state of one or more respective parts, either by relative movement between the parts or without relative movement, such as by altering a magnetic state of one of the parts. Where the restraint employs a detent or other mechanism, for example, comprising interlocking crown gears or magnetically interacting parts instead of a friction clutch, that mechanism may nevertheless be engaged and disengaged by rotation of the respective crank, for example, by axial movement of a threaded component in a similar way to the plate 36 described above, so that it is operable by the user in a similar manner to the illustrated embodiment.

Preferably as in the above described embodiment the restraint acts as a brake to restrain the drum against rotation, although in alternative embodiments it could act directly on the cable.

In alternative embodiments, the crank could be for example a disc or handwheel rather than an elongate arm, with the handle being attached at its periphery. The winch drum could be any reel or other arrangement suitable for reeling and unreeling the cable, such as a smooth or helically grooved cylinder or an arrangement of bars defining a cage around which the cable is wrapped.

In alternative embodiments, particularly on smaller pitches, a single net deployment apparatus may be provided, with the or each cable being attached at its distal end to a suitable securement on the opposite side of the pitch to support the net in the extended position.

In further alternative embodiments, the novel winch assembly could be mounted for example on a boundary structure 15 of the sports pitch rather than on a post, and could be used without a net storage arm or upper cable wheel.

In yet further alternative embodiments, the or each net deployment apparatus may comprise a post with a net storage arm and upper cable wheel, but only a single winch for the upper cable, with no lower cable being provided; optionally, the lower edge of the net may be weighted to hold it in position in use.

Many further adaptations are possible within the scope of the claims.

Claims (16)

1. A winch assembly for use in deploying a net on a sports pitch by means of a pair of upper and lower cables arranged in vertically spaced relation to support respective upper and lower edge regions of the net in an extended position of the net; the assembly comprising a pair of winches, each winch including: a drum for receiving a respective one of the cables in a retracted position of the net, a restraint having an engaged condition and a disengaged condition, and a crank rotatable about a first axis to drive said drum in rotation independently of the drum of the respective other winch, the crank including a handle; each restraint being arranged in the engaged condition to prevent the respective cable from unreeling from its drum when under strain in the extended position of the net, and in the disengaged condition to allow the respective cable to be unreeled from its drum; each handle having a nominal second axis defined by a line parallel with the first axis of its respective crank and passing through a central point of said handle, each second axis describing a swept circle in a plane normal to the first axis of the respective crank as the handle of said crank is rotated about the first axis of said crank to drive its respective drum in rotation; wherein the swept circle contains the first axis of the crank of the respective other winch.

2. A winch assembly according to claim 1, wherein the crank of each winch is rotatable in a first direction to engage the respective restraint and to reel the respective cable onto its drum and in a second, opposite direction to disengage the respective restraint and to unreel said cable from its drum.

3. A winch assembly according to claim 2, wherein the crank of each winch comprises a mass sufficient to re-engage the respective restraint from its disengaged condition by inertial reaction of said crank to rotation of the respective drum when its handle is released by a user in a maximally strained condition of the respective cable.

4. A winch assembly according to claim 3, wherein the crank of each winch is adjustable between a use condition in which the crank is rotationally engaged with the respective drum and an idle condition in which the crank is rotationally disengaged from the respective drum, so that the drum can rotate freely when the respective restraint is disengaged and the respective crank is in the idle condition.

5. A winch assembly according to claim 2, wherein the restraint of each winch includes a friction clutch.

6. A winch assembly according to claim 5, wherein said clutch is engaged and disengaged by movement of a pressure control element along the first axis of the respective crank, said pressure control element being mounted for rotation on a screw thread about the first axis.

7. A winch assembly according to claim 1, wherein the first axes are collinear or are substantially parallel and separated by a distance less than half the average radius of the swept circles.

8. A winch assembly according to any preceding claim, including: a post, the winches being mounted on the post; an arm extending outwardly from an upper end region of the post, the post being arranged to support the upper cable so that it extends along the arm in use; and a wheel rotationally mounted at a distal end of the arm to support the upper cable as it passes over the wheel during operation of the respective winch.

9. A net deployment apparatus for use on a sports pitch, including: a net; a pair of upper and lower cables arranged in vertically spaced relation to support respective upper and lower edge regions of the net in an extended position of the net; and a winch assembly according to any of claims 1 - 7 for reeling and unreeling the cables.

10. A net deployment apparatus for use on a sports pitch, including: a net; a pair of upper and lower cables arranged in vertically spaced relation to support respective upper and lower edge regions of the net in the extended position of the net; and a winch assembly according to claim 8 for reeling and unreeling the cables; and further including a plurality of suspension rings connected to the upper edge region of the net, the upper cable passing through the suspension rings to suspend the net from the upper cable; the wheel being arranged to pass through the suspension rings so that the suspension rings can slide along the arm as the net is returned to a retracted position so as to suspend the net from the arm.

11. An installation comprising two net deployment apparatuses according to claim 9 or claim 10, the apparatuses being arranged respectively on opposite sides of a sports pitch, the respective upper and lower cables being detachably connected together in the extended position of the nets.

12. A winch assembly for use in deploying a net on a sports pitch by means of an upper cable arranged to support an upper edge region of the net in an extended position of the net; the assembly including: at least a first winch; a post, the first winch being mounted on the post; and an arm extending outwardly from an upper end region of the post, the post being arranged to support the cable so that it extends along the arm in use; the first winch having a drum for receiving the upper cable in a retracted position of the net, and a crank rotatable about a first axis to drive the drum in rotation, the crank including a handle; the assembly further including a wheel mounted for rotation at a distal end of the arm to support the upper cable as it passes over the wheel during operation of the first winch, and a plurality of suspension rings for supporting the upper edge region of the net when the suspension rings are threaded onto the cable, the wheel being arranged to pass through the suspension rings so that the suspension rings can slide along the arm as the net is returned to the retracted position so as to suspend the net from the arm.

13. A winch assembly according to claim 12, including a second winch mounted on the post, the second winch having a drum and a crank rotatable about a first axis to drive said drum in rotation independently of the drum of the first winch, the crank having a handle; the drum of the second winch being arranged to receive a lower cable for supporting a lower edge region of the net.

14. A net deployment apparatus for use on a sports pitch, including: a net; at least one cable for supporting the net in an extended position of the net; and a winch assembly according to claim 12 or claim 13 for reeling and unreeling the at least one cable.

15. An installation comprising two net deployment apparatuses according to claim 14, the apparatuses being arranged respectively on opposite sides of a sports pitch, the respective cables being detachably connected together in the extended position of the nets.

16. A net deployment apparatus substantially as described with reference to the accompanying drawings.