GB2490342A

GB2490342A - A roller for attachment to a vehicle

Info

Publication number: GB2490342A
Application number: GB201107003A
Authority: GB
Inventors: Peter Loveday
Original assignee: Twose of Tiverton Ltd
Current assignee: Twose of Tiverton Ltd
Priority date: 2011-04-27
Filing date: 2011-04-27
Publication date: 2012-10-31
Anticipated expiration: 2031-04-27
Also published as: GB2490342B; GB201107003D0

Abstract

A roller for attachment to a vehicle comprises a roller having a frame 12, the frame having an attached roller drum 16 rotating about a axis A. The roller further comprises a hitch member 28 for connection to the vehicle, the hitch member defining a hitch point 15 at a first end and connected to the frame in a pivotable manner with a rotation axis B at a second end. The roller can be changed, by relative rotation of the frame and hitch member about rotation axis B, from a rolling configuration where the rotation axis A is substantially perpendicular to the hitch member, to a stowed configuration where the rotation axis A is not substantially perpendicular to the hitch member. The frame may include a pivot arm 36 connected to the frame in a pivotable manner such that it can rotate about a rotation axis C and a tie bar 66 pivotally connected to the pivot arm. Also disclosed is a method for changing the configuration of a roller.

Description

A Roller for Attachment to a Vehicle The invention relates to a roller for attachment to a vehicle, in particular a roller for attachment to a tractor, the roller being able to be towed so that the roller can be used for rolling, and also so that the roller can be towed on wheels for transporting the roller.

Rollers for attachment to a tractor, such that the roller can be used to roll over ground behind the tractor and flatten or treat the ground (for example with a shaped roller), are known. In order to transport the roller between rolling locations, without damaging the roller, for example by rolling it along a road, it is known to provide a pair of wheels which can be used to support the roller off the ground during transport.

Such rollers are generally wider than the tractor which tows them. However, when the roller is being transported, it is preferable that the roller does not extend either side of the tractor. A known roller has two hitch points, one hitch point located perpendicular to the rotation axis of the drum of the roller, to be used for hitching the roller when rolling, and the other hitch point located at the end of the roller, in line with the rotation axis of the drum of the roller, for connecting to the tractor when transporting the roller. In order for the user to switch between the two hitch points, the user must unhitch the roller and move either the roller or the tractor, and rehitch the roller using the other hitch point. This is inconvenient and time consuming for the user.

The object of the present invention is to provide an alternative arrangement for attaching a roller in two different configurations to a vehicle.

According to a first aspect of the present invention, there is provided a roller for attachment to a vehicle such that the roller is towed behind the vehicle, the roller comprising a frame, the frame comprising a formation for receiving a roller drum for rotation about a rotation axis A, the roller further comprising a hitch member for connection to a vehicle, the hitch member defining a hitch point at a first position on the hitch member and being connected to the frame in a pivotable manner with a rotation axis B at a second position on the hitch member, the second position being spaced apart from the first position, such that the roller can be changed, by relative rotation of the frame and hitch member about the rotation axis B, from a rolling configuration in which the rotation axis A is substantially perpendicular to the hitch member, to a stowed configuration in which the rotation axis A is not substantially perpendicular to the hitch member. In changing the roller from the rolling configuration to the stowed configuration, the user does not need to unhitch the roller fromthe vehicle.

It will be noted that the axis B is generally vertical in use. By "generally vertical" we mean within 80 to 110 degrees of a ground plane in use.

Preferably, the first position on the hitch member is at one end of the hitch member and the second position is at the other end of the hitch member. Preferably, in the stowed position, the rotational axis A is substantially parallel to the hitch member. This ensures that the narrowest dimension of the drum of the roller is presented perpendicular to the direction of travel, so that the width of the roller when towing can be minimised.

By "substantially perpendicular to the hitch member" is is meant substantially perpendicular to a straight line joining the first position on the hitch member and the second position on the hitch member. Likewise, by "substantially parallel to the hitch member", it is meant substantially parallel to a straight line joining the first and second positions.

Preferably, the rotation axis A is substantially perpendicular to and substantially passes through the rotation axis B. In the stowed configuration, this allows the roller to be positioned symmetrically relative to the hitch point, to minimise the extent which the roller protrudes either side of the hitch point when being towed.

Preferably, the roller further comprises a frame moving device to move the frame about the rotation axis B so that the roller is changed from the rolling configuration to the stowed configuration. The frame moving device may be powered by an actuator such as a hydraulic actuator connectable to the tractor's hydraulic power source. This allows the user to change the configuration of the roller, without having to manually move the roller about the rotation axis B. Preferably, the length of the hitch member is such that it overlaps the edge of the frame when the roller is in the stowed configuration. More preferably it overlaps the edge of the frame when the roller has been rotated by 90 degrees such that axis A is aligned with the direction of travel. This ensures that the roller can rotate into a stowed configuration, without any need for an extension separating the hitch point on a vehicle from the vehicle.

Preferably, the frame includes a pivot arm, the pivot arm being connected to the frame in pivotable manner such that it can rotate about a rotation axis C, the roller further including a tie bar, the tie bar being pivotally connected to the pivot arm at a first tie bar joint and pivotally connected to the hitch member at a second tie bar joint such that the relative positions of the first tie bar joint and the second tie bar joint cause relative rotation of the frame and the hitch member when the pivot arm is rotated about rotation axis C such that the roller can be changed from a rolling configuration to a stowed configuration, the frame moving device acting to pivot the pivot arm. The frame moving device may be an hydraulic ram connected to the frame. The pivot arm and the hydraulic ram provide a simple but effective means of rotating a frame relative to the hitch point.

By "relative rotation of the frame and the hitch member", it is meant relative rotation of the frame and a straight line joining the first position on the hitch member and the second position on the hitch member.

The formation for receiving a roller drum may comprise formations for receiving two adjacent roller drums with aligned axes of rotation, the two adjacent roller drums being able to rotate independently. The rotation axis B may lie between the two adjacent roller drums. This helps movement of the frame when moving the roller between configurations.

Preferably, the roller further comprises a pair of wheels on opposite sides of the axis A, the wheels being moveable from a first position in the rolling configuration in which they are in an elevated position in use and not in contact with the ground, to a second position in the stowed configuration, in which they are in a lower position in use, the wheels being movable between the first and second positions by means of the frame moving device. The wheels can thereby support the frame when the roller is in the stowed configuration such that any roller drum received by the frame will be held off the ground, the wheels being located such that they will be either side of a roller drum received by the frame. The location of the wheels either side of the roller drum ensures a compact arrangement for towing, rather than extending the length of the roller as in a configuration where the wheels are located at the end of the frame.

The roller may comprise a roller drum disposed within the roller drum receiving formation, the roller drum defining a lower rolling edge in use, in which in the elevated position the wheels are above the lower rolling edge in use and in the lower position the wheels are below the lower rolling edge in use. Preferably, the S each wheel is rotatably mounted to a wheel lever being pivotally connected to the frame with a rotation axis C, at a wheel lever connection, and each wheel can be moved from the first position to the second position by rotation about of the wheel lever about the rotation axis C. Preferably, the wheel levers are mounted to the frame such that when moving from the second position to the first position, the wheel levers must be moved over centre such that the wheels first move away from the axis A before moving toward the axis A.. Therefore, in order to retain the wheels in the second position, continued application of the force which moves the wheels from the first position to the second position is not needed.

Preferably the respective axes of rotation of the wheels are aligned and substantially perpendicular to the rotation axis A (and horizontal in use). Preferably, the aligned axes of rotation of the wheels in the second position are on an opposite side of the centre of gravity of the roller to the hitch point in the stowed configuration.

The roller is therefore supported in the stowed configuration, without undue force being exerted on the hitch.

Preferably the wheel levers are connected to each other such that they can be moved in unison by a single point of force. Preferably, the wheel levers are connected to each other above the frame. Further, the wheel levers can be located close to the centre of gravity of the roller, which ensures more even weight distribution when in the rolling configuration.

The wheel levers may be connected to and moved by the pivot arm.

Therefore, movement of the wheels and the frame can be conveniently carried out by a single device or actuator. The wheel levers may be connected to the pivot arm via at least one link piece, the link piece being connected in a pivotal manner to both wheel levers and the pivot arm. The positioning of the wheels is therefore not restricted by the position of the pivot arm, as the length of the link piece can be varied.

The wheel levers may be connected to the pivot arm at a position further than the first tie bar joint from the pivot arm joint. The or each wheel lever may be connected to the pivot arm at a position forward of the first tie bar joint in the direction of rotation of the pivot arm joint towards the hitch arm joint. Therefore, rotation of the pivot arm has a relatively greater effect initially on the wheel levers than on the tie bar, aiding movement of the wheels into the second position before relative rotation of the frame and hitch is complete.

S According to a second aspect of the present invention there is provided a roller for attachment to a tractor, the roller comprising a frame, the frame comprising a formation for receiving a roller drum for rotation about a rotation axis A, the roller further comprising a pair of wheels, the wheels being moveable from a first position in which they are in an elevated position in use, to a second position, in which they are in a lower position in use, the wheels being located on opposite sides of the axis A. The roller may comprise a roller drum disposed within the roller drum receiving formation, the roller drum defining a lower rolling edge in use, in which in the elevated position the wheels are above the lower rolling edge in use and in the lower position the wheels are below the lower rolling edge in use.Preferably, each wheel is rotatably mounted to a wheel lever, each wheel lever being pivotally connected to the frame with a rotation axis C, and the wheels are moved between the first and second positions by pivoting movement of the wheel lever about rotation axis C. The wheel levers are preferably connected to each other above the roller drum such that they can be moved in unison by a single point of force. Preferably, the wheel levers are mounted to the frame such that when moving from the second position to the first position the wheel levers must be moved over centre such that the wheels first move away from the axis A before moving towards the axis A. According to a third aspect of the present invention, there is provided a method of changing a roller between a rolling configuration and a stowed configuration for transport comprising the steps of: providing a roller comprising a frame, the frame comprising means for receiving a roller drum with a rotation axis A, the roller further comprising a hitch for connection to a vehicle, the hitch being connected to the frame in a pivotable manner with a rotation axis B, relatively rotating the frame and the hitch about the rotation axis B from a rolling configuration in which the rotation axis A is substantially perpendicular to the direction of travel of the hitch in use, to a stowed configuration in which the rotation axis A is not substantially perpendicular to the direction of travel of the hitch in use.

According to a fourth aspect of the presen.t invention there is provided a roller for attachment to a vehicle such that the roller is towed behind the vehicle, the roller comprising a frame, the frame comprising a formation for receiving a roller drum for rotation about a rotation axis A, the roller further comprising a hitch for connection to a vehicle, the hitch point being connected to the frame in a pivotabie manner with a rotation axis B, such that the roller can be changed, by relative rotation of the frame and hitch about the rotation axis B, from a rolling configuration in which the rotation axis A is substantially perpendicular to the direction of travel of the hitch point in use, to a stowed configuration in which the rotation axis A is not substantially perpendicular to the direction of travel of the hitch point i.n use.

By "direction of travel of the hitch point in use", it is meant the direction of the hitch point when the vehicle is travelling continuously in a straight line. Obviously, there will be times when a roller is being towed when the delay in the change of direction of the roller after a change in direction of the vehicle means that the rotation axis A is not perpendicular to the direction of travel of the hitch point at that precise moment in time.

Preferably, in the stowed position, the rotation acis A is substantially parallel to the direction of travel of the hitch point in use. Preferably, the hitch point is connected to the frame via a hitch member.

Any of the preferred features of the first statement of invention are also

applicable to this fourth statement of invention.

An embodiment of the invention will now be described with reference to the figures, in which: Fig. 1 is a perspective view from one side of the roller of the present embodiment, in the rolling configuration; Fig. 2 is a perspective view from the same side as Fig. 1, at 90° to Fig. 1; Fig. 3 is a perspective view of the embodiment of Fig. 1, from the other side of the roller, at 90° to Fig. 1; Fig. 4 is a perspective view of the embodiment of Fig. 1, on the opposite side of the roller from Fig. 1, and at 180° to the view of Fig. 1; Fig. 5 is a plan view of the roller of Fig. 1; Fig. 6 is a side view of the roller of Fig. 1; Fig. 7 is an end view of the roller of Fig. 1; Fig. 8 is a perspective view from one side of the roller of the present embodiment, in the stowed configuration; Fig. 9 is a perspective view from the same side as Fig. 8, at 900 to Fig. 8; Fig. 10 is a perspective view of the embodiment of Fig. 8, from the other side of the roller, at 90° to Fig. 8; Fig. 11 is a perspective view of the embodiment of Fig. 8, on the opposite side of the roller from Fig. 8, and at 180° to the view of Fig. 8; Fig. 12 is a plan view of the roller of Fig. 8; Fig. 13 is a side view of the roller of Fig. 8; Fig. 14 is an end view of the roller of Fig. 8, and Fig. 15 is an end view of the roller of Fig. 8.

The roller 10 comprises a frame 12 and a hitch 14. A roller portion comprising two cylindrical drums 16 is received in the frame by means for receiving the roller portion 18. The drums 16 are arranged coaxially, with a rotation axis A, and can rotate independently. The hitch 14 is in the shape of a ring. When the roller 10 is connected to a vehicle by the hitch 14, the hitch 14 will contact the vehicle at a hitch point 15 on the hitch 14. The hitch 14 is connected to the frame 12 by a hitch member or arm 28. The roller 10 is changeable from a rolling configuration in which the rotation axis A is substantially perpendicular to the hitch member, to a stowed configuration in which the rotation axis A is not substantially perpendicular to the hitch member. In fact, in the present embodiment, in the stowed configuration, the rotation axis A is parallel to the hitch member. The drums 16 define a lower rolling edge 17 of the roller 10, where the drums 16 contact the ground when the roller is in the rolling configuration.

The frame 12 comprises a deep top elongate beam 20 which extends along the top of the roller 10, parallel with the rotation axis A, from a first end 21 of the roller to a pivotal joint 23. Two shallow top elongate ribs 25 extend from the pivotal joint 23, to the second end 27 of the roller 10. The shallow top portions 25 are parallel to each other and to rotation axis A, but are spaced apart such that they are symmetrical with the deep top portion 20. The frame 12 further comprises two elongate side members 22, one each side of the roller 10, also parallel to the rotation axis A. At the first end 21 of the roller, the top beam 20 and the side members 22 are joined by connection elements 24 which extend from the ends of the beam 20 and members 22 perpendicular to the elongate dimension of the beam 20 and members 22, to meet at a central connection portion 26. Likewise, at the second end 27 of the roller 10, the shallow top ribs 25 and the side members 24 are joined by connection elements 24 to meet at a central connection element 26. The means for receiving the roller portion 18 extend from the central connection elements 26. The top beam 20 and the side members 22 are separated by 90° relative to rotation axis A, such that the side members 22 are diametrically opposite each other relative to the rotation axis A, and thedrumsl6.

The hitch 14 is connected to the top beam 20 of the frame 12 by the hitch arm 28 via the pivotal joint 23. The hitch arm 28 comprises a first hitch arm portion 30 and a second hitch arm portion 32. The hitch 14 is at the free end of the second hitch arm portion 32. The first hitch arm portion 30 is joined at its free end to the top beam 20 of the frame 12 via the pivotal joint 23. The pivotal joint 23 has a rotation axis B. The rotation axis B is perpendicular to and passes through the rotation axis A. The rotation of the first hitch arm portion 30 is limited by a stop 34 at the end of the top beam 20. The first arm portion 30 is of a similar length to the shallow ribs 25, such that, in the stowed configuration, when the hitch arm 28 is parallel to the rotation axis A, the first hitch arm portion 30 extends parallel to a point in line with the end of the frame 12. The first hitch arm portion 30 is attached to the second hitch arm portion 32 such that the first hitch arm portion 30 can pivot up and down, to adapt the height of the hitch 14 for suitable connection to tractors with different connection heights.

The frame 12 further includes a pivot arm 36 pivotally attached to the top beam 20 via a first axle 39 which is perpendicular to the rotation axis A. The pivot arm 36 comprises two planar sections 37, linked by the first axle 39 and a second axle 41 and a third axle 43. The pivot arm 36 is joined to the top beam 20 of the frame 12 via the first axle 39. The rotation axis of the first axle 39 is perpendicular to the rotation axis A. The plane of movement of the second and third axles 41, 43 when the pivot arm 36 pivots is parallel with the rotation axis A. An hydraulic ram 40 is attached to the top beam 20 of the frame 12 at the end 21. The ram 40 is pivotally attached to the frame 12 via an axle 45 which is perpendicular to the rotation axis A. The extending portion of the ram 40 is pivotally attached to the pivot arm 38 via the second axle 41, the rotation axis of the second axle 41 being parallel to that of the first axle 39. The ram 40 extends towards the rotation axis B. The plane of movement of the ram 40 is the same as that of the second and third axles 41, 43 of the pivot arm 36. In the refracted state, the ram 40 extends slightly upwardly from the axle 45 to the axle 41 on the pivot arm 36. The planar sections 37 of the pivot arm 36 have a slight bulge 47 on the side between the first axle 39 and the second axle 41. Therefore, when the ram 40 is retracted, and the pivot arm 36 rests on the top beam 20, the bulge 47 contacts the top beam 20. The second axle 41 is thus elevated relative to the first axle 39. This, and the fact that the ram 40 extends slightly upwardly when refracted, ensures that, when the ram 40 is extended, there is an upward component to its extension, so that the pivot arm 36 is pivoted.

The roller 10 includes a pair of wheels 44, 46 which have their axles aligned and perpendicular to the rotation axis A. The wheels 44, 46 are located on opposite sides of the rotation axis A. The axle of each wheel 44, 46 extends through a respective wheel lever 48, 50. Each wheel lever 48, 50 extends from its respective wheel axle parallel to rotation axis B. The frame 12 has wheel lever supports 52, 54 which extend between the top beam 20, from a position just behind the stop 34, and the respective side member 22. Each wheel lever 48, 50 is pivotally attached to a respective wheel lever support 52, 54 by means of an axle 58. The rotation axis C of each wheel lever axle 58 is perpendicular to rotation axis B, and thus also the direction of extension of the wheel levers 48, 50, such that the levers 48, 50 and the wheels 44, 46 can be rotated about the axles 58 without contacting the frame 12.

The wheel levers 48, 50 are joined by an arched portion 60 at their non-wheel ends 48, 50 the arched portion 60 arches over the top beam 20 of the frame 12. The arched portion 60 is pivotally connected at its midpoint to a link piece 62, with a rotation axis parallel to that of the first axle 39 of the pivot arm 36. The link piece 62 is pivotally attached to the pivot arm 36 via the third axle 43, the rotation axis of which is parallel to that of the first axle 39.

In the rolling configuration, the arched portion 60 lies against the top beam 20 and the wheels are on the opposite side of the lever axle 58, the wheel levers 48, 50 being arranged such that the wheels 44, 46 are in an elevated position in which the wheels 44, 46 are above the lower rolling edge, i.e. they are off the ground. When the pivot arm 36 is rotated by the hydraulic ram 40 about the first axle 39 towards the rotation axis B, the arched portion 60 is moved over the top beam of the lever axle 58, such that the wheels are moved underneath the axle 58, i.e. over centre. The arched portion 60 is moved until it contacts the hitch arm 28. In this position, the wheel levers 48, 50 are in a lower position, in which the wheels 44, 46 are below the lower rolling edge, i.e. they are in contact with the ground, and support the drums 16 off the ground.

The first, second and third axles 39, 41, 43 on the pivot arm 36 describe a triangle in which the angle between the sides extending from the first axle 39 is degrees, the angle of the sides extending from the second axle 41 is degrees and the angle of the sides extending from the third axle 43 is degrees. When the roller 10 is in the stowed configuration, the third pivot point 64 is closer to the hitch arm rotation axis B than the second axle 41.

A tie bar 66 is pivotally joined to the pivot arm 36 at a first tie bar joint 68 via an axle 69 which extends outwardly of one side of one of the plates 37 of the pivot arm 36, parallel with the first axle of the pivot arm 36. The tie bar 66 is pivotally joined to the second hitch arm portion 32 at a second tie bar joint 70 located on the side of the hftch arm 28 via an axle 71 which is parallel to the rotation axis B and thus perpendicular to the axle 69 of the first tie bar joint 68. Both the first tie bar joint 68 and the second tie bar joint 70 are situated to the side of the pivotal joint 23 which it is desired the hitch arm 28 will extend from in the rolling configuration. The first tie bar joint axle 69 is closer to the first axle 39 of the pivot arm 36 than the second or third axles 41, 43 and is slightly behind the second axle 41 in the direction of motion of the pivot arm 36 towards the rotation axis B. In the stowed configuration, the longitudinal axes of the top beam 20 and the second hitch arm portion 32 are aligned (and also aligned with the rotation axis A), but the tie bar 66 is not parallel with them, as the distance of the second tie bar joint 70 from the longitudinal axis of the second hitch arm portion 32 is less than the distance of the first tie bar joint 68 from the pivot arm 36. The second tie bar joint 70 is positioned from the rotation axis B a distance which is greater than the distance of the first tie bar joint 68 from the pivot arm 36. Therefore, in the rolling configuration, when the hitch arm 28 is perpendicular to the longitudinal axis of the top beam 20 (and therefore also to the rotation axis A), the tie bar 66 is not parallel with the longitudinal axis of the top beam 20.

In use, in the rolling configuration of the roller 10, the hitch arm 28 and frame 12 are arranged such that the rotation axis A is substantially perpendicular to the direction of travel of the hitch in use, i.e. the hitch arm 28 is perpendicular to the rotation axis A, and therefore also perpendicular to the elongate direction of the top beam 20 of the frame 12. In the rolling configuration, the hydraulic ram 40 is retracted, and so the wheels 44, 46 are lifted and do not interfere with the rolling of the roller 10.

In order to change the roller from the rolling configuration to the stowed configuration, the user operates the hydraulic ram 40 so that the hydraulic ram 40 is extended. This causes the pivot arm 36 to rotate about the first pivot point 38, causing movement of the second pivot point 42 towards the arched portion 60. As previously described, the arched portion 60 is pushed over the wheel lever axles 58 so that the wheels 44, 46 initially contact the floor on the opposite side of the lever axles 58 from the hydraulic ram 40 and then move over centre, such that the wheel axles are located on the hydraulic ram 40 side of the lever axles 58. The wheels 40, 42 are held in a ground contacting position by contact between the arched portion 60 and the hitch arm 28.

The pivoting movement of the pivot arm 36 also causes the third axle 43 of the pivot arm 36, and thus also the first tie bar joint 68, to be moved parallel to the rotation axis A towards the hitch arm 28. Therefore, as the hydraulic ram 40 is applied, the tie bar 66 produces a clockwise force D on the hitch arm, as indicated by the arrow in Figure X, which causes relative rotation of the hitch arm 28 and the frame 12 about rotation axis B. As the hitch arm 28 is attached to the tractor, most of the relative rotation is caused by rotation of the frame 12. The hydraulic ram 40 thus acts as a frame moving device. As the tie bar 66 is not perpendicular to the hitch arm 28 in the rolling configuration, this allows more effective pivoting of the frame 12. As relative rotation occurs, the angle between the hitch arm 28 and the tie bar 66 increases, thus increasing the component of the force which is directed to rotation.

Thus, more rotation occurs towards the end of the movement of the pivot arm 36 by the hydraulic ram 40. The degree of pivoting about rotation axis B is limited by contact of the hitch arm 28 with a stop 74 attached to the end of the frame 12. The fact that there are two roller drums 16 which can rotate independently aids rotation of the frame 12 before the wheels 44, 46 have elevated the roller drums 16.

In the stowed configuration, rotation axis A is parallel to the direction of travel of the hitch 14 in use, thus the width of the roller 10 perpendicular to the direction of travel is minimised. The fact that the wheels 44, 46 are located either side of the drums 16 minimises the roller length and so allows the roller 10 to be compact for towing. In addition, in the rolling configuration the wheel positioning allows more even weight distribution across the roller 10. Further, the arched position 60 allows the wheel to be pivoted over centre, so that continued force does not need to be provided by the hydraulic ram 40 to counteract the compressive force caused by the weight of the roller acting on the wheels/wheel levers and maintain the position of the wheels to support the drum off the ground. As the wheels 44, 46 are located behind the rotation axis B, they are behind the centre of gravity of the roller 10 relative to the hitch 14, which improves stability when the roller 10 is being towed.

When a user wants to change the roller 10 from the stowed configuration back to the rolling configuration, the process is reversed, i.e. the hydraulic arm 40 is retracted causing relative movement between the frame 12 and the hitch arm 28 in the opposite direction, and movement of the arched portion 60 towards the hydraulic arm 40, such that the wheels 44, 46 move over centre and are lifted. The non-parallel orientation of the tie bar 66 relative to the top beam 20 and the hitch arm 28, in the opposite sense to when the roller 10 is in the rolling configuration, causes relative rotation between the top beam 20 and the hitch arm 28 in the opposite direction to when changing from the rolling to the stowed configuration. In the above embodiment, the hitch arm 28 is straight. However, it could be any shape provided that it connects the hitch point 15 to a second position at which the hitch member 28 is connected to the frame 12. As previously discussed "perpendicular/parallel to the hitch member" is intended to mean "perpendicular/parallel to a straight line joining the first (i.e. the hitch point) and second positions" and so it is not necessary for the hitch arm to be straight. In the above embodiment, a hydraulic ram is used as the frame moving device and also to move the wheels. Alternatively, a different means of moving the frame and wheels could be used. Further, separate means of moving the wheels and frame could be used, for example separate hydraulic rams. The wheels do not need to be joined, and there could be provided separate moving means for each wheel.

A roller could be provided without wheels. For example, once rotated from the rolling configuration to the stable configuration, the roller drum could be elevated off the ground for towing by means of the hitch arm.

In the above embodiment, the hydraulic ram and pivot arm are located centrally along the longitudinal length of the frame, but this need not be the case, as long as the hydraulic ram is able to impart motion in the correct directions on the frame/hitch arm and on the wheels.

The hitch need not be on the end of a hitch arm as in the above embodiment, but could be located directly on the frame and attached to a vehicle by an arm projecting from the back of the vehicle instead.

Claims

CLAIMS1. A roller for attachment to a vehicle such that the roller is towed behind the vehicle, the roller comprising a frame, the frame comprising a formation for receiving a roller drum for rotation about a rotation axis A, the roller further comprising a hitch member for connection to a vehicle, the hitch member defining a hitch point at a first position on the hitch member and being connected to the frame in a pivotable manner with a rotation axis B at a second position on the hitch member, the second position being spaced apart from the first position, such that the roller can be changed, by relative rotation of the frame and hitch member about the rotation axis B, from a rolling configuration in which the rotation axis A is substantially perpendicular to the hitch member, to a stowed configuration in which the rotation axis A is not substantially perpendicular to the hitch member.
2. A roller according to claim 1, wherein, in the stowed position, the rotation axis A is substantially parallel to the hitch member.
3. A roller according to claim 1 or claim 2, wherein the rotation axis A is substantially perpendicular to and substantially passes through the rotation axis B.
4. A roller according to claim 1, claim 2 or claim 3, wherein the roller further comprises a frame moving device to move the frame about the rotation axis B so that the roller is changed from the rolling configuration to the stowed configuration.
5. A roller according to any preceding claim, wherein the length of the hitch member is such that it overlaps the edge of the frame when the roller is in the stowed configuration.
6. A roller according to claim 5 or claim 6, wherein the frame includes a pivot arm, the pivot arm being connected to the frame in pivotable manner such that it can rotate about a rotation axis C, the roller further including a tie bar, the tie bar being pivotally connected to the pivot arm at a first tie bar joint and pivotally connected to the hitch member at a second tie bar joint such that the relative positions of the first tie bar joint and the second tie bar joint cause relative rotation of the frame and the hitch member when the pivot arm is rotated about rotation axis C such that the roller can be S changed from a rolling configuration to a stowed configuration, the frame moving device acting to pivot the pivot arm.
7. A roller according to claim 6, wherein the frame moving device is a hydraulic ram connected to the frame.
8. A roller according to any preceding claim, wherein the formation for receiving a roller drum comprises formations for receiving two adjacent roller drums with aligned axes of rotation, the two adjacent roller drums being able to rotate independently.
9. A roller according to claim 8, wherein the rotation axis B lies between the two adjacent roller drums.
10. A roller according to any preceding claim, wherein the roller comprises a pair of wheels on opposite sides of the axis A, the wheels being moveable from a first position in the rolling configuration in which they are in an elevated position in use, to a second position in the stowed configuration, in which they are in a lower position in use, the wheels being movable between the first and second positions by means of the frame moving device.
11. A roller according to claim 10 comprising a roller drum disposed within the roller drum receiving formation, the roller drum defining a lower rolling edge in use, in which in the elevated position the wheels are above the lower rolling edge in use and in the lower position the wheels are below the lower rolling edge in use.
12. A roller according to claim 10 or 11, wherein each wheel is rotatably mounted to a wheel lever, each wheel lever being pivotally connected to the frame at a wheel lever connection, and each wheel can be moved from the first position to the second position by pivoting movement of the wheel lever about the wheel lever connection.
13. A roller according to claim 12, wherein the wheel levers are mounted to the frame such that when moving from the second position to the first position the wheel levers must be moved over centre such that the wheels first move away from the axis A before moving toward the axis A.
14. A roller according to any of claims 10 to 13, wherein respective axes of rotation of the wheels are aligned and substantially perpendicular to the rotation axis A.
15. A roller according to claim 14, wherein the aligned axes of rotation of the wheels in the second position are on an opposite side of the centre of gravity of the roller to the hitch in the stowed configuration.
16. A roller according to any of claims 12 to 15, wherein the wheel levers are connected to each other such that they can be moved in unison by a single point of force.
17. A roller according to claim 16, when the wheel levers are connected to each other above the frame.
18. A roller according to claim 16 or claim 17, wherein the wheel levers are connected to and moved by the pivot arm.
19. A roller according to claim 18, wherein the wheel levers are connected to the pivot arm via at least one link piece, the link piece being connected in a pivotal manner to both wheel levers and the pivot arm.
20. A roller according to claim 18 or claim 19, wherein the wheel levers are connected to the pivot arm at a position further than the first tie bar joint from the pivot arm joint.
21. A roller according to any of claim 19 or claim 20, wherein the or each wheel lever is connected to the pivot arm at a position forward of the first tie bar joint in the direction of rotation of the pivot arm joint towards the hitch arm joint.S22. A roller substantially as described herein and with reference to Figs. 1 to 14.23. A roller for attachment to a tractor, the roller comprisinga frame, the frame comprising a formation for receiving a roller drum for rotation about a rotation axis A, the roller further comprising a pair of wheels, the wheels being moveable from a first position in which they are in an elevated position in use, to a second position, in which they are in a lower position in use the wheels being located on opposite sides of the axis A..24. A roller according to claim 23, comprising a roller drum disposed within the roller drum receiving formation, the roller drum defining a lower rolling edge in use, in which in the elevated position the wheels are above the lower rolling edge in use and in the lower position the wheels are below the lower rolling edge in use.25. A roller according to claim 23 or claim 24, wherein each wheel is rotatably mounted to a wheel lever, each wheel lever being pivotally connected to the frame with a rotation axis C, and the wheels are moved between the first and second positions by pivoting movement of the wheel lever about rotation axis C. 26. A roller according to claim 25, wherein the wheel levers are connected to each other above the roller drum such that they can be moved in unison by a single point of force.27. A roller according to claim 23, claim 24, or claim 25, wherein the wheel levers are mounted to the frame such that when moving from the second position to the first position, the wheel levers must be moved over centre such that the wheels first move away from the axis A before moving toward the axis A. 28. A method of changing a roller between a rolling configuration and a stowed configuration for transport comprising the steps of: providing a roller comprising a frame, the frame comprising means for receiving a roller drum with a rotation axis A, the roller further comprising a hitch for connection to a vehicle, the hitch being connected to the frame in a pivotable manner with a rotation axis B, relatively rotating the frame and the hitch about the rotation axis B from a rolling configuration in which the rotation axis A is substantially perpendicular to the direction of travel of the hitch in use, to a stowed configuration in which the rotation axis A is not substantially perpendicular to the direction of travel of the hitch in use.