GB2487312A

GB2487312A - Transfer wheel markers

Info

Publication number: GB2487312A
Application number: GB1202463.4A
Authority: GB
Inventors: Kevan Wightman
Original assignee: VITAX Ltd
Current assignee: VITAX Ltd
Priority date: 2009-10-06
Filing date: 2010-10-06
Publication date: 2012-07-18
Anticipated expiration: 2030-10-06
Also published as: GB201220273D0; GB201016843D0; GB2474751A; GB2487312B; GB2474751B; GB201202463D0; GB2493864A; GB2493864B; GB0917477D0

Abstract

A transfer wheel marker comprises: a tank for carrying paint mounted on a pair of primary ground-engaging wheels 3 and having a handle 4 to be pushed or pulled along by an operator; and a transfer wheel assembly comprising a plurality of transfer wheels 5,6 & 7 arranged to pick up paint from within the tank and transfer the paint between them to the exterior of the tank and onto the ground surface to be marked. The central transfer wheel 6 is mounted in the tank such that it may be disengaged from the front transfer wheel 7 without being demounted. The tank is formed as a plastics moulding and is mounted on a base frame 8 bearing the primary ground-engaging wheels. Also disclosed is an arrangement for adjusting the lateral position of the central transfer wheel 6 (see figures 21 and 22). Further disclosed is a spot brush and/or drip filter provided in an emptying opening 14 (see figures 23 and 24).

Description

Transfer Wheel Markers

Field of the Invention

The present invention concerns improvements in and relating to transfer wheel markers such as are used, for example, for line-marking of sports

s fields.

Background to the Invention

Transfer wheel markers for line-marking of surfaces such as sports fields! football pitches etc, are generally very conservative in their design, being a steel fabricated, powder coated or sprayed, open topped box of welded steel panels defining a paint carrying chamber. The box stands on two ground-engaging wheels on a pair of tube steel axle stubs welded to the side of the box. It has a long-stemmed handle to be pushed or pulled along by the grounds-man or other operator. The paint in the chamber of the box is delivered to the ground by a transfer wheel assembly generally comprising three transfer wheels (also known as loading wheels') arranged in a series longitudinally of the chamber that passes through the upper part of the chamber front wall. The first transfer wheel, usually of aluminium, is mounted on an axle within the chamber of the box to pick up paint from the chamber and transfer it to a centre transfer wheel, which may be a rubber-tyred wheel as in our own Briteliner 400 Series TM The centre transfer wheel straddles the front wall between the interior and exterior of the box. A third transfer wheel, also normally of aluminium, carried on the exterior of the box is in ground-engagement when applying paint and receives the paint from the centre transfer wheel and applies it onto the ground surface to be marked.

The box itself forms the tank of the unit with all the peripherals bolted onto it, including the handle stem, guide plates for the loading and transfer wheels and scrapers! brushes. ln all instances the paint is loaded into the tank from the top and emptied by either a sump plug or by physically lifting the machine up and tipping the unused paint out.

The fact that this type of unit has an all steel construction raises many difficulties with the unit itself. Firstly, the weight of these units is very high, of the order of 20 kg or more, making them difficult to lift or carry around.

When users need to transport their machine form their depot to where they are marking out, they have to lift the machine into or onto the back of a vehicle to drive to where they need to be. Manual handling of one of these units becomes an issue, as two people are required to safely lift it.

A second drawback to conventional unit design is their poor aesthetics.

The existing machines do not have a very good look'. They are basic looking and boxy giving no impression of any kind of quality due to the fact the machine looks so basic. Thirdly, limited capacity is an issue. The capacity of most such machines is about 18 litres. To mark a standard size football (Soccer) pitch consumes approximately 7 litres of paint product.

This means that only two pitches can be marked with this type of machine before it needs re-filling. A fourth problem is corrosion. Over time, due to the nature of the machines and the environment in which they are used, the protective powder coating/spraying on the machine will wear off, be chipped or scraped away and the machine will begin to rust. Once this begins it will only deteriorate quickly and often necessitates the purchase of a new machine Being steel the machine can be easily damaged whilst in transit or in use.

The steel axle stubs can easily be bent out of true (eg by knocks in transit), jamming the wheels against the box and/ or causing the machine to no longer run straight and any knock to the tank itself will cause it to be dented or twisted out of shape. If the tank is actually holed it will require being welded to repair it and this is not something everyone has access to and can be expensive. In the main, if the tank is damaged it will need replacing and, as this is the main part of the machine, it is a costly thing to have to do.

The machines are not easy to empty. The sump plug is generally quite small, approximately an 18mm aperture on some models, and is easily blocked with paint making the emptying process all the more difficult. One of the biggest drawbacks is that the sump plug unscrews and is often stiff and difficult to unscrew. If the level of left over paint product in the tank is above the level of the sump, the paint product will begin to run out as you unscrew the plug. This will cause paint product to spill over the user and the floor and creates a lot of mess. If you have to tip the machine up to empty it, it is still a very heavy piece of equipment to try and lift when empty, let alone when it still has paint product in it. The machine will need to be lifted off the ground and tipped completely over to empty the paint outfromthetop.

Many users do not take any time to properly empty and clean this type of unit. Over time a residue of dry paint product begins to build up in the bottom of the tank. This can sometimes become very deep and might be as much as an inch thick at some point. This is because the machine is so heavy and cumbersome to move around, users do not have the time or patience to clean it properly. As the machine is viewed as a basic marker with no electrics or pump, users tend to view it as a cheap' machine and do not exercise much concern over the cleaning and general maintenance of the unit. Also, as more and more dried paint builds up in the tank, it greatly increases the weight of the overall unit and promotes a greater risk of corrosion around the bottom of the tank. Along with the normal process of rusting, failure to clean the machine regularly will greatly reduce its lifespan. Furthermore, it must be said that, even if the machine is maintained properly and efficiently, the fact that a steel constructed unit is being cleaned with water presents its own problems in terms of corrosion.

There are very few replaceable parts on the current machines. If the tank needs replacing it is normal that a whole new machine will have to be purchased. The aluminium and centre transfer wheels can be replaced, as can scrapers and brushes but this is generally the limit of the ability to replace parts on this type of machine. On many units it is possible to keep the main machine but replace the aluminium and centre transfer wheels, to enable the user to change the size of line, e.g. to go from a 4 inch line to a 3 inch line. Some units however, do not even have this ability and to change the size of line width needed requires the purchase of a whole new machine with the correct size aluminium and transfer wheels on.

In the existing machines the handle is mounted on the main frame via two brackets and is a solid fix once in place. The handle height can be adjusted but this requires the undoing of nuts and bolts and is not easy to achieve, particularly when corrosion sets into these nuts and bolts and causes them to seize. The handle is also welded and can be prone to breaking/snapping over time when corrosion sets in, as all the weight of the machine is controlled via the handle. Being a solid assembly, the handles make transportation cumbersome and fixed handles are prone to damage in transit. The existing machines have a very short wheelbase - 400mm -which, whilst giving greater control when marking circles, is difficult to keep in a straight line and, as most lines on a standard soccer pitch are straight, this can become an issue. Being short machines, they tend to be slightly back heavy and it is relatively easy to inadvertently tip the machine back when in normal use.

In the existing machines the centre transfer wheel is essentially sitting loosely' on the two aluminium wheels. The centre wheel is generally guided in place by two adjustable bolts that are situated either side of the wheel and are wound' in or out to centralise the wheel perfectly in line with the two aluminium ones. The centre transfer wheel can be weighted with sand or water to achieve different line definitions I.e.: if more sand or water is filled into the centre wheel, less line marking liquid will be applied to the wheels and therefore less line marking liquid will be applied to the grass surface. This adjustment is rough' and not easily controlled. If a change of line definition is required during marking, the centre wheel must be removed and either emptied or filled as desired. This is very awkward and incredibly messy to do, as the centre wheel will be coated in line marking liquid and will need to be held by hand to achieve. Being loose on the machine, the centre transfer wheel has the possibility to bounce around whilst in use. Generally, this does not happen on good smooth surfaces but can become a problem when the machine is used on rough or pitted surfaces. This will affect the quality of the finished line. Also, being loose, there is always the possibility of the centre wheel being easily removed from the body of the machine and getting lost, particularly as the wheel must be removed to disengage the paint supply and for cleaning.

This always begs the question of where do I put the wheel once I want to disengage it?' if the centre wheel is not removed, the operator must tilt the machine backwards to ensure that the front aluminium wheel is not touching the ground, to ensure no unnecessary marking is achieved by mistake. This is awkward and in no way infallible.

The cost of producing the conventional type of unit is very high since the steel content itself is quite considerable. The steel box is completely welded along its seams and welding services are priced per inch and this becomes an expensive process. The finished box is always coated for protection and this is an added cost on top. If importing these items, as many people do, there is also the implication of currency exchange rates to be considered. Many of these machines are manufactured abroad and imported into the UK. Not many, if any, are actually manufactured in the UK. As many of these machines are imported, there can be a very long lead-time involved from order to point of delivery. This creates two main issues. One is that if the supplier has no stock, the customer will have to wait several weeks for stock to come in. The second is that the supplier will keep high stock levels to ensure that this does not happen. This means the supplier will have a lot of high value stock on the shelf that has been paid for but will not be sold for, potentially, a long time.

All in all, this type of machine is heavy, cumbersome and, although it is a basic machine, it is not entirely user friendly. It has a limited life span due to certain points in its design and can be easily neglected because it has an image of being cheap'.

It is an object of the present invention to address the issues detailed above and eliminate as many as possible whilst improving the overall quality and look of the machine and making the machine more user friendly' and cost effective.

Summary of the Invention

According to a first aspect of the present invention there is provided a transfer wheel marker that comprises: a tank for carrying paint mounted on ground-engaging wheels and having a handle to be pushed or pulled along by an operator; a transfer wheel assembly comprising a plurality of transfer wheels arranged to pick up paint from within the tank and transfer the paint between them to the exterior of the tank and onto the ground surface to be marked, wherein the tank is formed as a plastics moulding and is mounted on a base frame bearing the ground-engaging wheels.

Particularly preferably the tank is formed by a rotational moulding process and suitably as a substantially enclosed form. Rotational moulding confers exceptional strength on the structure for a given thickness of plastics.

Preferably an upper opening is machined, eg routed, into the form for access by the transfer wheels. The transfer wheels may be installed or removed with ease for repair or replacement eg with different width wheels for different line-marking jobs.

Within the tank a pair of opposing receptacle! cradle formations are suitably provided as an integral feature of the moulding each of the pair to receive a respective opposing end of an axle or a respective axle stub of the first transfer wheel that picks up the paint from the tank. This suitably comprises V-shaped recesses or slots, each being V-shaped as viewed in side elevation of the tank. Such arrangement allows for quick and simple exchange of the inner! first transfer wheel that is awkward to exchange on existing transfer wheel markers.

Suitably the tank is demountably mounted on the base frame and preferably is clipped or otherwise resiliently held on the frame. Preferably this is such that the frame will absorb substantial impact forces and that the tank will dislodge or demount from the frame rather than be damaged by the impact.

Particularly preferably the base frame is of tubular steel construction and preferably comprises a pair of arms that extend substantially parallel to the sides of the tank so that the tank is supported by and sits between the arms, cradled and suitably gripped by the arms.

Suitably the moulded form of the tank has a lateral rib running a substantial part of the length of each side of the tank to serve as a support shoulder by which each side of the tank seats on the respective arm.

The arms of the frame may be extended to form a handle stem of the handle of the transfer wheel marker. In the preferred embodiment the frame! arms and the handle are a unitary structure that tilts as one about the axis of the ground-engaging wheels. Preferably the tank mounts to the frame by a mounting that allows the tank to tilt relative to the frame so that it may be thereby up-ended. This may allow emptying of the tank, where the tank is provided with a top rear opening for that purpose.

Suitably the demountable mounting of the tank to the base frame comprises a recess or hook formation on the underside of the tank as a receptacle for a transverse member of the base frame, suitably such as

S

the axle of the ground-engaging wheels, allowing the tank to tilt relative to the frame. Resilient detent lugs or other resilient means may be provided in the frame transverse member receptacle to demountably capture the transverse member therein.

Suitably the arms and handle are of one length or of contiguous! interlinked lengths of tubing that extend as an arm along one side of the tank and which arm bends to become the handle stem and bends again to become the opposing arm along the other side of the tank.

Preferably the arms converge at the front end of the tank and support the axis! axle of the transfer wheel that delivers the paint to the ground in use.

Brief Description of the Drawings

Preferred embodiments of the present invention will now be more particularly described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view from above of a first preferred embodiment of the transfer wheel marker, with the molded tank hooked and clipped in place on the wheeled frame! chassis; Figure 2 is a side elevation view of the transfer wheel marker of Figure 1; Figure 3 is a rear elevation view of the transfer wheel marker; Figure 4 is a plan view of the transfer wheel marker from above; Figure 5 is a longitudinal sectional view of the transfer wheel marker; Figure 6 is a side elevation view corresponding to Figure 2 but with the tank tilted upright in its hook! cradle mount to the base frame to facilitate emptying via the rear top opening (near-side wheel removed for clarity); Figure 7 is a plan view corresponding to Figure 4 but of the tank only, and the transfer wheels not yet having been installed or having been removed for repair or replacement; Figure 8 is a plan view corresponding to Figure 7 and illustrating, by cross-hatching, the area of the moulding that is initially closed but opened out! cut out by post-machining, eg routing, of the moulding; Figure 9 is a side elevation view corresponding to Figure 2 but of the tank only; Figure 10 is a front elevation view of the tank only; Figure 11 is a rear elevation view corresponding to Figure 3 but of the tank only; Figure 12 is a longitudinal sectional view corresponding to Figure 5 but of the tank only ( section as taken along the line A-A in Figure 7); Figure 13 is a transverse sectional view through the tank only (section as taken along the line B-B in Figure 9); Figure 14 is a transverse sectional view through the tank only (section as taken along the line C-C in Figure 9).

Figure 15 is a perspective view of a second embodiment of the transfer wheel marker, shown in disassembled state; Figure 16 is a perspective view of the second embodiment machine in assembled state and with tank tilted upright as for emptying; Figure 17 is a perspective view of the second embodiment in assembled state with tank down and handled folded down for stowage; Figure 18 is a close-up view of the second embodiment, focusing on the eyelet hook! ring for marking arcs! circles; Figure 19 is a close-up view of the second embodiment focusing on the tank height adjustment means, showing tank front lowered state; Figure 20 is a close-up view of the second embodiment focusing on the tank height adjustment means, showing tank front raised state; Figure 21 is a close-up view of the second embodiment focusing on the central transfer wheel mounting arrangement and adjustment and locking means; Figure 22 is a close-up view of the second embodiment central transfer wheel showing the centering and locking adjustment means; Figure 23 is a close-up view of the second embodiment machine's emptying opening accommodating an optional extra spot-marking brush; and Figure 24 is a view corresponding to Figure 23 and in which the brush is lifted out of the opening.

Description of the Preferred Embodiment

Referring to Figure 1, this shows the transfer wheel marker 1 fully assembled and in its normal ground-engaging state for use. The transfer wheel marker 1 has in common with the conventional transfer wheel markers a configuration comprising a tank 2 mounted on a pair of ground-engaging wheels 3 and a handle 4 extending upwardly from near the rear of the tank 2. The handle 4 has a handle stem 4a that suitably extends upwardly to a height of the order of 1.1 m tall (height above ground) for the handle bar 4b to be at a level for easy reach by a person of average height while standing upright or leaning forward.

The transfer wheel marker 1 of the preferred embodiment also shares with the prior devices the configuration of the transfer wheel assembly. Three transfer wheels 5, 6, 7 (also known as loading wheels') are arranged in a series longitudinally of the tank 2 that passes through or over the upper part of the tank front wall. The first transfer wheel 5 is of aluminium and is mounted on an axle 5a within the tank 2 to pick up paint from the tank 2 and transfer it to a rubber-tyred centre transfer wheel 6 that straddles the front wall between the interior and exterior of the tank 2. A third transfer wheel 7 of aluminium carried on the exterior of the tank 2 is in ground-engagement when applying paint and receives the paint from the centre transfer wheel 6 and applies it onto the ground surface to be marked in use.

Beyond these basic features in common with the conventional transfer wheel markers the design of the machine is markedly different from the conventional. The machine is not built as a unitary steel box tank and frame with the ground-engaging wheels and handle depending from the tank 2, but instead it comprises an independent rotationally moulded plastic tank 2 that demountably sits onto a tubular steel frame 8 and with the tubular steel frame 8 having the main ground-engaging wheels 3 and handle 4 on it. The tank 2 and frame 8 are two separate parts and the tank 2 clips onto the frame 8 for use. The frame 8 is manufactured from triple-coated 19mm steel tube and does not need to be sprayed or powder coated for protection as the triple coating already provides this. Neither the frame 8 nor the tank 2 has any welding. The components of the assembly are simply clipped or bolted together. Accordingly the assembly is not vulnerable to any weld joint failures unlike the prior machines and the tank 2, being plastic, is completely protected from any kind of corrosion and will never degrade or fail over time.

In the embodiment illustrated in figures 1 to 14, the frame 8 is formed of a single tube or as a single continuous! contiguous series of tube lengths defining a pair of arms 8a that each extend along a respective opposing side of the tank 2 to support the tank 2. The pair of ground-engaging wheels 3 is mounted on a primary axle 9. The primary axle 9 is held on the tubular steel frame 8 by a pair of U-shaped metal mounting cradles 9a.

Each axle-mounting cradle is fixed to a rear end of a respective one of the opposing arm lengths 8a. The arms 8a converge at the front end of the tank 2 but are not joined together there. Instead the convergent front ends 8b of the arms 8a provide a support for the external transfer wheel 7 that is carried on an axle 10. The axle 10 is held to the arms 8a in the same manner as the primary axle 9, ie it is held at each end by a respective one of a pairof metal mounting cradles ba.

At the rear end of the tank 2 the arms 8a are joined together by a rectangular hoop-shaped length of the tubing that defines the handle 4.

The handle stem 4a comprises a pair of substantially mutually parallel lengths of the tubing that extend upwardly from the rear end of the arm lengths 8a and which are linked at their upper ends by a length of the tubing that defines the handle bar 4b.

The tubular frame 8 can be bent and formed to shape in-house and then bolted together across its axles 9, 10 by bolting the U-shaped metal mounting cradles 9a and 1 0a over their respective axle 9, 10 and onto the arms 8a. This gives the frame strength and rigidity but also incorporates a certain amount of flexibility in the frame. This will allow any damage to be absorbed by the frame and minimise permanent damage. Furthermore, because the frame is not a single solid piece, even if it were bent or twisted out of shape by a blow, it would be very easy to return it back to its original shape. The front end of the framework is finished off by a fender! bumper bar or rod 15 (see Figures 16, 17) bolted in-between the side arms 8a, 8b, across and in front of the front aluminium transfer wheel 7.

This gives the frame extra strength but also acts as a bumper protection for the aluminium transfer wheel 7. This feature prevents anything from immediately damaging the aluminium wheel 7 as it will first impact the bumper 15 before the wheel 7, e.g. if the machine is inadvertently pushed up to and into a goal post, the bumper 15 will take the impact, not the aluminium transfer wheel 7.

In the first illustrated embodiment the handle 4 and frame 3 are unitary and the angle between the handle stem 4a and arms 8a is a constant angle, hereshown as an obtuse angle of approximately 100° to give a rearward rake to the handle stem 4a. In variants of this embodiment the handle may be initially separate or separable from arms 8a of the frame.

Furthermore, in other embodiments, such as the second embodiment of Figure 15 onwards, the angle between the handle stem 4a and arms 8a may be adjustable by hinges/pivots allowing the handle stem 4a to fold forward/collapse against the arms 8a for stowage in a compact form without the need to remove the handle 4 from the frame 8.

In the illustrated embodiments the primary axle 9 is a single long bar that is bolted across the underside of the frame and doubles as the mounting bar for the tank 2 itself. This gives the axle 9 more strength and eliminates any possibility of damage to the axle 9 if the wheels 3 do get knocked.

The handle 4 is suitably made from the same tube as the frame 8 and is height adjustable by undoing two rotary knobs 16 (see Figure 17) and repositioning the handle 4 at the desired height. The handle 4 of the second embodiment pivots at the rotary knobs 16 when sufficiently un-screwed and will fold down across the machine for storage and transportation and does not need to be removed from the machine. The frame 8 further has two side braces 18 either side, linking the bottom part 8a, 8b of the frame to the handle upright stems 4a, just below where the handle pivots. This provides strength to the frame 8 as it absorbs the weight of the machine so that all the weight is not on the handle 4.

The machine in all embodiments has a longer wheelbase than prior machines, being 500mm or greater and preferably 590mm. This gives it much greater stability and accuracy when marking straight lines. Most of the lines on a standard soccer pitch are straight and well catered for by the present machine. Having a longer wheelbase and indeed longer machine also gives better weight distribution across the machine. This means that the front transfer wheel 7 is more solidly held on the marking surface by its own natural weight.

The handle 4 in the second embodiment has a detachable cow horn bar 4c across the top (Fig 16). This gives the user more leverage when turning the machine and when marking circles. The handle 4 in the second embodiment further has an eyelet ring 17 attached to the side of the machine -here shown as being on the side braces 18 (Fig 17). This enables the operator to tie a string line to the machine when marking circles by a process such as follows. The process is: 1) hammer a stake into the very centre of the pitch and loop a rope to this stake (the rope is at a set length, half the circumference of the centre circle); 2) next tie the other end of the string to your machine and push the machine round. The string will keep the machine running in a perfect circle as long as it is kept taut.

Turning now in detail to the form of the tank 2, the tank 2 is moulded by a rotational moulding process and has a comparatively more complex and refined shape than the box-shaped tank of the prior art. The overall form of the tank 2 is relatively more enclosed from above, compared to the conventional completely open-topped boxes. Indeed the top 2b of the tank may be initially moulded with the major part thereof, including the central area thereof closed with the plastics material but may be partially opened out by post-machining! routing in the relatively central hatched area H as shown in Figure 8 to provide a central access for the paint to be poured in and for insertion and removal of the first transfer wheel 5 and this cut-out opening leads to and is contiguous with the front opening for mounting of the central transfer wheel 6.

The overall shape of the moulded tank 2 is forwardly tapered in plan and profile at the frontal end of the tank 2 so that the top and bottom walls and the opposing side walls converge towards the zone where the external third transfer wheel 7 is mounted giving the tank 2 a more stream-lined appearance and also strengthening it in that area. The front wall 2a of the tank 2 has an arcuate or curved recess that curves in the vertical plane to better accommodate the front transfer wheel 7 closer in to the tank 2. The sidewalls 2c of the tank 2 at 2e extend forwardly beyond the front wall 2a and provide support and lateral protection for the external front transfer wheel 7.

The tank 2 has a sculpted appearance of its internal and external surfaces, with convex and concave features defining specialised mounting surfaces. In the interior the tank 2 is given a pair of inwardly opposing deep and broad V-shaped (as viewed in side elevation) recesses 11 that each serve as a mounting cradle for a respective opposing end of the axle 5a of the first transfer wheel 5. The bottom of each V-shaped recess 11 is rounded out to accommodate the axle 5a but is entered through a neck region that is slightly constricted by opposing resilient lugs to provide a resilient clip-type fitment of the axle 5a in place in the cradles 11. The V-shaped recesses 11 enable the user to quickly remove the internal first transfer wheel 5 and change it for a different size without having to undo any fixings. The whole wheel 5 and axle 5a simply snap into the bottom of the V and the machine is ready to go. In a variant of this In the second illustrated embodiment the bottoms of the V's 11 may be provided with threaded inserts! through holes in them and the axle 5a is screwed! bolted down into these inserts. This completely secures the axle 5a and internal first transfer wheel 5 in place and ensures it cannot move and affect the quality of the finished line. The user can remove the internal wheel 5 and change it for a different size. The whole wheel 5 and axle 5a simply pushes into the bottoms of the V shaped recesses 11 and then the axle 5a is screwed in place and the machine is ready to go. This also enables the internal wheel 5 to be removed for changing or for cleaning with ease and minimal fuss. When in use it is firmly held in place and cannot bounce' out of its location whilst the machine is being pushed along. Most current machines have the internal wheel 5 sat loosely on a bracket. It must be noted that the centre transfer wheel 6 must first be removed from the machine before the internal wheel 5 can be taken out.

The central transfer wheel 6 is positively fixed to the machine. This eliminates the wheel's ability to bounce and ensures the same quality of line being maintained on any surface that it is used on. It also ensures that the line being marked is consistent no. Being fixed, it also ensures that the central transfer wheel 6 cannot be inadvertently removed and lost. The central transfer wheel 6 is mounted on a spring-loaded mounting assembly 19 and can be adjusted up and down and left to right (Figs 21, 22). This enables the central transfer wheel 6 to be set to the desired height to achieve the desired line definition. The central transfer wheel 6 can be laterally centred with the two other aluminium transfer wheels 5, 7 with ease using lateral movement-limiting bolts 20 that can be screwed in or out to adjust left to right positioning Line definition adjustment can be made whilst in use and is achieved by winding up or down the central transfer wheel 6, even when the main tank 2 is loaded with line marking liquid. This ensures a mess free and simple operation, as the operator will not have to handle the central transfer wheel 6 or any parts that are coated in line marking liquid at all. The whole spring loaded assembly 19 is mounted on a pivot, which ensures that the central transfer wheel 6 will press evenly on both aluminium transfer wheels 5, 7 and therefore will deliver an even transfer of line marking liquid. Once set to the desired line quality, the central transfer wheel 6 does not have to be touched and will provide the same quality and line definition each time.

The central transfer wheel 6 can be disengaged without having to remove it from the machine. To allow this the tank 2 has two vertically slotted brackets 21 (see Figures 19, 20) fixed to its sides 18 and these locate over a bolt and rotary hand-adjustment knob assembly 22 on the frame 8. This locks the tank 2 in the down position when in normal use and ensures that the tank will not bounce around and cause quality issues when marking.

This also means that the machine can be used on any quality of surface with complete confidence. No matter how uneven or bumpy the surface is, the tank will not move. This feature also enables the tank 2 to be slightly raised and locked in a position where the central transfer wheel 6 is no longer touching the external aluminium wheel 5, effectively disengaging the transfer wheel 6 from the marking process. This means no inadvertent marking will take place and the user can transport the machine wheeled on all three of its ground-engaging wheels 3, 7 (ie including the front transfer wheel 7) instead of having to tip the machine back onto the main pair of wheels 3 only to ensure that the front aluminium wheel 7 is not touching the surface.

The user does not have to handle the central transfer wheel 6 to disengage it and will not inadvertently spill Line marking liquid on him or herself or any other surface, as the central transfer wheel 6 will be loaded with Line marking liquid at this point. Having the central transfer wheel 6 fixed also acts as a safety feature, in line with the tanks ability to tip to empty. When the tank 2 is tipped backwards (as in Figure 16), the central transfer wheel 6 will not fall off of the machine and cause any kind of damage or mess to either the central transfer wheel 6, the operator or the surface it is on. The central transfer wheel 6 can also be removed entirely if necessary. Therefore the whole process of moving from one pitch to another, or returning the marker after use is very user friendly.

On its exterior the tank 2 has further moulded mounting features. Firstly, there is a pair of ribs 12 moulded into it, each of which runs along the exterior of a respective one of the opposing side walls of the tank 2. Each rib 12 at its lower side defines a substantially straight, level shoulder 12a that abuts the upper surface of a respective tank 2 support arm 8a of the frame 8 when the tank 2 is mounted to the frame 8 so that the tank 2 is held in the frame 8 cradled between the arms 8a.

On the upper side of the ribs 12 they are each downwardly inclined towards the rear and serve as a shoulder 12b that acts as a stop point to abut against the handle stem 4a and prevent the tank 2 from pivoting all the way through the handle 4 when the tank 2 is tilted upright in the frame 8 to a vertical position for tank drainage as shown in Figure 6. The stop shoulder 12b of the ribs 12 allows the tank to sit in a completely vertical position without having to be held by the operator or without the danger of the tank flipping completely over and spilling paint! marking liquid or injuring the user.

Tilting of the tank 2 in the frame 8 is enabled by the nature of the mounting of the tank 2 to the frame 8. The tank 2 is moulded at its rear end underside to incorporate a groove 13 that runs right across the width of the tank 2. The primary axle 9 of the pair of ground-engaging wheels 3 hooks!seats into this groove 13 and this allows the tank 2 to pivot about the axle 9. The groove 13 demountably captures! clips the primary axle 9 in place by having a resilient flexing neck entry arrangement which could be similar to that of the V-shaped recesses 11. At the entrance!neck of the groove 13 are a pair of opposing moulded lugs' 13a, which flex over the bar (wheel axis! axle) of the frame that the tank connects to in order to clip' the tank in place.

The clipping arrangement of the groove 13 reliably holds the tank 2 onto the frame 8 while in use but enables it to be demounted and removed if necessary. Furthermore, any significant blow to the tank 2 would cause it to be unclipped from the frame 8 and fall off before it could actually damage the tank 2. There is little resistance to the blow when this occurs so there can be no damage to the tank 2.

For ease of emptying the design of the tank 2 as a separate section is very helpful. With the simple hooking attaching process of fitting the primary axle 9 to the groove 13 this enables the tank to be held in a horizontal position when it is in use but allows it to be flipped up' through the handle so that it is sitting in a vertical position for emptying.

The tank 2 is loaded with paint product through the top opening as normal but for emptying there is a separate, suitably, circular opening 14 provided on the top of the tank 2 at the rear. This allows any unused paint product to be poured gently out and kept for use another day. Because the tank 2 can be flipped up, there is no sump plug to remove and there is no need for the user to lift the machine to empty it. This enables the user to more effectively and efficiently empty the tank after every use. This method enables the user to drain as much paint as possible from the tank and eliminates the ability of residue paint to build up inside the tank.

Once nearly empty, the whole tank 2 can be easily removed from the frame 8 to fully drain. This is easily achievable because the tank 2 is very light -eg only 5 kg empty. Even if two to three litres of Line marking liquid were left in the tank it would still only weigh 8 to 10 kg and this is very easy to lift. Also, because the tank 2 is rotationally moulded plastic, the Line marking liquid will not stick to it and virtually all the residue line marking liquid will be emptied and can be saved for later use. This method enables the user to drain as much Line marking liquid as possible from the tank and eliminates the build up of residue inside the tank, thereby reducing wasted Line marking liquid. The machine will be the only model on the market with a tip to empty feature. The tank 2 comes supplied with a push on cap 23 (Figure 17) that goes over the emptying aperture 14.

This prevents any Line marking liquid sloshing' out during normal use.

With regard to the second embodiment of Figure 15 onwards, when in the vertical position, the tank 2 is stopped from flipping completely through the handlebars 4a by a pivot stop bar 24 (see Figure 17) running across the rear of the frame 8, this ensures no spillage of Line marking liquid or injury to the operator. The tank 2 rests on this bar 24 at a point between the internal aluminium wheel 5 and the central transfer wheel 6. This prevents these two wheels 5, 6 from being damaged when the tank 2 is flipped up.

The tank 2 here again itself has an external ridge 12 moulded into it and this acts as the stop point for the tank 2 when it is in the horizontal position. The pivot stop bar 24 also acts to strengthen the frame 2 at the rear of the machine.

The weight of the new transfer wheel marker is considerably less than the original types at approximately 13kg, being nearly half that of current transfer wheel markers. This eliminates the manual handling issues associated with the machine and makes it much easier and more comfortable to move and carry around. It is now perfectly possible and acceptable for only one person to lift and carry this machine.

Aesthetically the new machine is much more streamlined and looks more professional in appearance. It is no longer boxy and has much nicer lines to it creating a look of quality. The capacity of the new transfer wheel marker is approximately 24 litres. This enables the user to mark a minimum of three standard size football (Soccer) pitches before it needs to be refilled. Because of the reduction in weight of the new design -when empty it weighs only about 15kg, this actually creates an advantage in the full weight of the machine itself. The new design filled with 24 litres of Vitax BritelineTM marking liquid only weighs 50.44 kg. Because the machine itself is so much lighter, even with the addition of six extra litres of marking liquid, the overall weight remains lower and all of the manual handling problems with the prior art machines are considerably alleviated. It is much easier to carry around and manageable for one man to lift and carry.

The tank 2 of this machine will never corrode or rust, due to its being manufactured form rotationally moulded plastic. It is impossible for corrosion to occur. The steel tube frame 8, suitably including the handle 4 and primary axle 9, has triple protection from corrosion and will last many years in the field. The ability of the machine to be damaged is, furthermore, greatly reduced with the new design. Rotationally moulded plastic is very flexible and can withstand a hefty knock' and not be damaged, as it will move' with the blow. The plastic itself is suitably moulded to approximately 3mm in thickness, which gives it its own residual strength but the design also has many strengthening points built in, giving the tank much more strength throughout.

For cleaning, since the new machine has this unique tank tilting feature it is easier to ensure that all residual paint is emptied from the tank 2. This makes cleaning the tank 2 easier when marking has finished. Because the tank 2 is of rotationally moulded plastic it can be thoroughly cleaned with water, without fear of long-term damage to the tank 2. No amount of use of water on this tank 2 will cause it any problems at all. A jet wash could be used as there is no danger of damaging the powder coating or spraying as it has neither of these. The tank 2 can also be scraped out to clean as much as possible off of it. It is easier to clean the plastic tank 2 than the steel one, as the paint product is less liable to stick to the plastic. Because the tank is removable it is also possible to take the tank 2 off of the frame 8 to aid the cleaning process. If residue paint product has been allowed to dry out in the tank 2, it is very easily remedied. You would simply remove the tank 2 from the frame 8, turn it upside down and bang the bottom of the tank 2 to break up and dislodge the dried out paint. This would easily fall off of the plastic tank 2 and could then be thrown away. Once done, the tank 2 would be back to good as new.

All parts on the new machine are replaceable. This allows the user more flexibility when owning this machine. If a tank 2 is actually damaged beyond repair, it can be immediately replaced without having to purchase a whole new machine. Any part of the frame can also be replaced, as can all the normal peripherals such as the wheels etc. The transfer wheels 5,6,7 are interchangeable to change the size of the line width required, without the need to purchase a new machine. The quick snap in mounting feature of the internal transfer wheel 5 enables it to be removed for changing or cleaning with ease and minimal fuss. When in use it is firmly held in place and cannot bounce' out of its location whilst the machine is being pushed along. This is in contrast to most current machines, which have the internal transfer wheel 5 sat loosely on a bracket.

The moulded tank 2 has been found to be considerably cheaper to manufacture than the steel one. The tubular frame 8 is also considerably cheaper than the existing steel parts and together the tank 2 and frame 8 represent major, eg 50%, savings on cost. The tank 2 and frame 8 can be produced in the UK and the assembly of the machine can be done in house, thereby avoiding import costs and issues with currency exchange rates. There does not need to be any welding or, indeed, any steel plate fabrication in the manufacturing and assembly and this contributes to the much lower cost price involved. As the machine can be made in house, there will not be any issues of stock. The machines can be made to order if necessary so there will not be any inordinate lead times on delivery.

Additional features may be provided that can be purchased with the machine or as an optional extra. These include a unique drip filter 25 and spot brush 26 (see Figures 23 and 24). To install, the push on cap 23 is removed and replaced with the drip filter 25, which fits securely in the emptying aperture 14. The spot brush 26 is a round brush that is then placed inside the drip filter 25. This brush 26 may be used to mark out the centre spot, penalty spot and for completing the line right up close to the goal posts. The brush 26 is simply dipped into the main tank 2, to coat it with Line marking liquid, used and then placed back into the drip filter 25.

The drip filter 25 is a coarse mesh filter that allows any residue Line marking liquid to drip' off the brush 26 and back into the tank 2, whilst still preventing any Line marking liquid form sloshing out during normal use.

The brush 26 and filter 25 will then be cleaned alongside the main machine, the brush 26 can also be used to aid in cleaning the tank 2 and all the transfer wheels 5, 6, 7.

Claims

Claims 1. A transfer wheel marker that comprises: a tank for carrying paint mounted on primary ground-engaging wheels and having a handle to be pushed or pulled along by an operator; and a transfer wheel assembly comprising a plurality of transfer wheels arranged to pick up paint from within the tank and transfer the paint between them to the exterior of the tank and onto the ground surface to be marked, wherein the tank is formed as a plastics moulding and is mounted on a base frame bearing the primary ground-engaging wheels and wherein the central transfer wheel is mounted in the tank such that it may be disengaged from the front transfer wheel without being demounted.
2. A transfer wheel marker as claimed in claim 1, wherein the tank is formed by a rotational moulding process.
3. A transfer wheel marker as claimed in claim 1 or 2, wherein the tank is formed as a substantially enclosed form in which an upper opening is machined into the form for access by the transfer wheels.
4. A transfer wheel marker as claimed in claim 1, 2 or 3, wherein the tank is demountably mounted on the base frame.
5. A transfer wheel marker as claimed in claim 4, wherein the tank is clipped or otherwise resiliently held on the frame.
6. A transfer wheel marker as claimed in claim 5, wherein the frame will absorb substantial impact forces and the tank will dislodge or demount from the frame rather than be damaged by the impact.
7. A transfer wheel marker as claimed in any preceding claim, wherein the base frame is of tubular metal or alloy construction.
8. A transfer wheel marker as claimed in any preceding claim, wherein the base frame comprises a pair of arms that extend substantially parallel to the sides of the tank so that the tank is supported by and sits between the arms, cradled and suitably gripped by the arms.
9. A transfer wheel marker as claimed in claim 8, wherein the moulded form of the tank has a lateral rib running a substantial part of the length of each side of the tank to serve as a support shoulder by which each side of the tank seats on the respective arm.
10. A transfer wheel marker as claimed in claim 8 or 9, wherein the arms of the frame are extended to form a handle stem of the handle of the transfer wheel marker.
11. A transfer wheel marker as claimed in claim 10, wherein the frame! arms and the handle are a unitary structure that tilts as one about the axis of the primary ground-engaging wheels.
12. A transfer wheel marker as claimed in claim 10 or 11, wherein the arms and handle are of one length or of contiguous! interlinked lengths of tubing that extend as an arm along one side of the tank and which arm bends to become the handle stem and bends again to become the opposing arm along the other side of the tank.
13. A transfer wheel marker as claimed in any of claims 8 to 12, wherein the arms converge at the front end of the tank and support the axis! axle of the transfer wheel that delivers the paint to the ground in use.
14. A transfer wheel marker as claimed in any preceding claim wherein the top of the tank is closed over by a top wall for a substantial part thereof and an opening is provided in the top wall at a rear end thereof for emptying the tank.
15. A transfer wheel marker as claimed in any preceding claim wherein the tank is mounted to the frame by a mounting arrangement whereby the tank may tilt in the frame through approximately 90° to an upended position.
16. A transfer wheel marker as claimed in any preceding claim wherein the tank is mounted to the frame by a mounting arrangement that comprises a groove, channel or hooking means whereby the tank may tilt in the frame.
17. A transfer wheel marker as claimed in any preceding claim wherein the tank is mounted to the frame by a mounting arrangement that includes a clipping means whereby the frame is clipped to the tank.
18. A transfer wheel marker as claimed in claim 15 or 16 wherein the tank has a lateral rib or other formation on a side wall that defines a shoulder to act as a stop to abut against the handle when the tank is upended.
19. A transfer wheel marker as claimed in any preceding claim having inter-changeable transfer wheels to enable altering of marked line width.
20. A transfer wheel marker as claimed in any preceding claim wherein the wheelbase (between axle of primary ground-engaging wheels to axle of front transfer wheel) is at least 500mm.
21. A transfer wheel marker as claimed in any preceding claim wherein all transfer wheels are fully replaceable.
22. A transfer wheel marker as claimed in any preceding claim wherein the handle has a folding handle stem.
23. A transfer wheel marker as claimed in any preceding claim wherein the wheel marker has a hook or eye thereon to which a tether may be attached to allow the marker to mark out arcs or circles.
24. A transfer wheel marker as claimed in any preceding claim wherein the wheel marker has a bumper! fender at the front end thereof to protect the front transfer wheel.
25. A transfer wheel marker as claimed in any preceding claim wherein a central transfer wheel is mounted in the tank in a manner whereby it is demountably fixed in place.
26. A transfer wheel marker as claimed in claim 25 wherein the central transfer wheel is mounted in the tank by a spring loaded mounting arrangement.
27. A transfer wheel marker as claimed in claim 25 or 26 wherein the central transfer wheel is mounted in the tank by a pivoting arrangement.
28. A transfer wheel marker that comprises: a tank for carrying paint mounted on primary ground-engaging wheels and having a handle to be pushed or pulled along by an operator; and a transfer wheel assembly comprising a plurality of transfer wheels arranged to pick up paint from within the tank and transfer the paint between them to the exterior of the tank and onto the ground surface to be marked, wherein the tank is formed as a plastics moulding and is mounted on a base frame bearing the primary ground-engaging wheels and wherein the central transfer wheel is mounted in the tank having a lateral position adjustment! centreing arrangement.
29. A transfer wheel marker as claimed in any preceding claim wherein the central transfer wheel may be locked in the disengaged state.31. A transfer wheel marker as claimed in any preceding wherein the central transfer wheel may be locked in the engaged state.32. A transfer wheel marker as claimed in any preceding claim wherein the marker has a handle stem comprising a pair of uprights and with a transverse member extending between the uprights against which the tank may rest without impinging on the transfer wheels when the tank is tilted substantially upright.33. A transfer wheel marker as claimed in any preceding claim wherein an inner transfer wheel is mounted in a V-formation in the tank to bereadily demountable.34. A transfer wheel marker as claimed in claim 32 wherein the inner transfer wheel is lockable in the V-formation by a bolt or screw or is held firmly in use by a clip or friction-fit engagement.35. A transfer wheel marker that comprises: a tank for carrying paint mounted on primary ground-engaging wheels and having a handle to be pushed or pulled along by an operator; and a transfer wheel assembly comprising a plurality of transfer wheels arranged to pick up paint from within the tank and transfer the paint between them to the exterior of the tank and onto the ground surface to be marked, wherein the tank is formed as a plastics moulding and is mounted on a base frame bearing the primary ground-engaging wheels and wherein a spot brush and! or drip filter is provided that may fit to the emptying opening.