FIELD OF THE INVENTION The present invention relates to a trailer jack, an assembly comprising a trailer and a trailer jack and a method of reconfiguring a trailer jack between a first configuration and a second configuration. In particular, the present invention relates to a trailer jack having two configurations for lifting and supporting trailers. BACKGROUND TO THE INVENTION

A trailer jack refers to a jacking mechanism which is used to lift and support a trailer (towed/unpowered vehicle) when changing its tyres. In conventional motor vehicles, a jack is arranged to be located under the vehicle and is engaged with the underside of the chassis of the vehicle. The jack is then operated to increase the height and to thereby raise the vehicle from the ground. The height can be increased until the wheels adjacent to the jack are spaced from the ground such that the wheel can be removed and replaced. However, trailers may not possess a sufficient strengthened chassis or body shell by which the trailer could be raised by a conventional jack.

There are a variety of jacking mechanisms that have been developed which aim to raise a trailer by either a wheel or an axle rather than by the chassis or body shell. A trailer may be elevated by moving a wheel up a ramp in order to change a different wheel. In such products, a small ramp allows a driver to manoeuvre the trailer into an elevated position with a wedge to secure the ramp and wheel into place. This may support an adjacent wheel in a position spaced from the ground to enable the wheel to be removed and replaced. A trailer may also be lifted directly by an axle whereby the jack is substantially semi circular having two ends and a channel or a groove at one end for receiving an axle. The length of the jacking mechanism is longer than the distance between the axle and the floor. The vehicle may then be driven forward, rolling the jack to an upright position, such that the wheels associated with the axle are elevated and can be removed and/or replaced. It is highly preferable for the jacking mechanism to be small, simple and quick to use, such that on the road when a tyre is flat, it is an efficient process to change the tyre. Issues may arise when two or more of the vehicle's tyres are flat, or when the axle is not adequately supportive. Consequently, drivers may need to invest in both types of jacking mechanism.

Towing trailers are generally single axle or dual (or multi) axle. In a single axle trailer, the trailer has one (or more) wheel(s) located on the left hand side of the axle and one (or more) wheel(s) located on the right hand side of the axle. With single wheels on either side of the axle, the trailer must be raised by the axle itself if the trailer does not include a strengthened chassis or body shell. Accordingly a jack which engages with the underside of the axle is required.

In a dual or multi axle trailer, there are two or more parallel axles extending parallel but spaced apart across the width of the trailer. If a left hand wheel in a first axle needs removing, then a left hand wheel on the second axle can be driven up a ramp which will thereby raise the left hand wheel on the first axle to a position spaced from the ground.

Accordingly, trailer jacks are either engageable with an axle for a single axle caravan or engageable under a wheel for a multi-axle caravan. A user thereby purchases and transports the particular dedicated trailer jack which is appropriate. However, if a user upgrades or changes caravan then the user may need to purchase a new jack. In addition, a user may have a single axle trailer as well as a multi-axle trailer such that the user requires two separate jacks. Furthermore, in some circumstances, it may be preferred to raise a multi-axle caravan by the axle rather than by a wheel. The present invention aims to address the above problems, providing a solution to the single-purpose jack that currently exists.

It is an aim of the present invention to overcome at least one problem associated with the prior art whether referred to herein or otherwise.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention there is provided a trailer jack comprising a jack member comprising;

axle engagement means which is arranged to engage an axle of a trailer; a wheel transit surface for a wheel of a trailer to travel over; and

a peripheral ground engaging surface;

wherein the jack member is configurable between a first configuration and a second configuration in which,

in the first configuration;

a part of the peripheral ground engaging surface comprises a supporting region which supports the jack member on a ground surface; and

the axle engagement means is arranged to engage an axle of the trailer and wherein movement of the axle engagement means in a first direction causes the axle engagement means to pivotally move relative to the supporting region and for the distance between the axle engagement means and the ground surface to increase in order to raise the axle from the ground; and

in the second configuration;

the peripheral ground engaging surface of the jack member is arranged to rest on the ground surface and a wheel of a trailer is movable up the transit surface to raise the wheel away from the ground surface from a ground position to a raised position. In the first configuration, the movement of the axle engagement means in a first direction preferably refers to a forwards movement of the axle (and/or trailer) and may be as a result of being towed by a vehicle. In the first configuration, the movement of the axle engagement means in a first direction preferably refers to a translational movement of the axle (and/or trailer) over the ground surface.

Preferably, in the first configuration, the peripheral ground engaging surface rolls over the ground surface as the trailer jack moves from an initial position to a raised position. Preferably, in the first configuration, the supporting region moves position along the peripheral ground engaging surface as the trailer jack moves from an initial position to a raised position.

The peripheral ground engaging surface may move over the ground surface and for the supporting region to move to a final supporting location on the ground engaging surface

The supporting region may locate at an initial supporting location on the ground engaging surface

In the first configuration, the supporting region may remain statically positioned on the peripheral ground engaging surface as the trailer jack moves from an initial position to a raised position. The supporting region may be provided on a pivotable base. The pivotable base may comprise a plate or platform.

The jack member may comprise a body wherein the body may comprise a wedge shaped body. Preferably the wedge shaped body is formed between the peripheral ground engaging surface and the transit surface. Preferably the wedge shaped body increases in height from a first end towards a second end. Preferably the thickness of the wedge shaped body increases gradually (and preferably constantly) from a first end towards a second end.

The upper surface of the wedge shaped body may be arcuate and preferably is concave.

The lower surface of the wedge shaped body may be arcuate and preferably is convex. Preferably in the first configuration, the jack member is arranged for use with a single axle (trailer with a sole axle) trailer such that the single axle is raised such that a wheel mounted on one side of the single axle thereby is raised upwardly from the ground surface to an unsupported position which may then enable the wheel to be removed from the single axle.

In the first configuration, the initial supporting location is in a central position on the peripheral ground engagement surface and the contact region between the jack member and the ground surface moves towards the first end of the jack member as the axle moves in a first direction to raise the wheel from the ground surface.

Preferably the distance between the axle engagement means and the contact region is arranged to increase as the axle is moved in a first direction. Preferably this movement is arranged to raise a wheel mounted on the axle away from the ground and preferably raises the wheel to a position spaced form the ground. Conversely, as the axle is moved in a second direction, the distance between the axle engagement means and the contact region may be arranged to decrease and this distance may decrease until a wheel mounted on the axle supports the weight of the trailer on the ground. Preferably the contact region between the peripheral ground engagement surface moves around the peripheral ground engagement surface as the trailer moves translationally over the ground. Preferably the body of the jack member is arranged to pivot and/or rotate (and/or roll/rock) over the supporting ground surface.

Preferably the peripheral ground engagement surface is arranged to roll over the ground to move the contact region around the peripheral ground engagement surface as the trailer moves with respect to the ground surface.

Preferably in the second configuration, the jack member is arranged for use with a multi-axle (preferably dual axle) trailer such that a wheel on a first axle moves up the transit surface to a raised position and a wheel mounted on a second axle thereby is raised upwardly from the ground surface to an unsupported position which may then enable the wheel to be removed from the second axle.

Preferably a wheel moves up the transit surface from a first end towards a second end.

Preferably the peripheral ground engagement surface provides an initial contact region located at or towards the first end and as the wheel moves up the transit surface, the contact region moves towards the second end. Preferably the movement of a wheel up the transit surface causes the body of the jack member to roll (and/or pivot/rock) over the ground surface on which it is supported.

Preferably in the raised position, the first end of the body of the jack member is spaced from the ground surface.

Preferably the trailer jack comprises a stabilising means which may stabilise the body of the jack member in the second configuration with a wheel in the raised position. In the first configuration, the stabilising means may provide the supporting region for the peripheral ground engagement surface with the body of the jack member in the raised position. In the second configuration, the stabilising means may provide a part of the supporting region for the peripheral ground engagement surface with the body of the jack member in the raised position.

The stabilising means may comprise a stabilising attachment. The stabilising attachment may be detachable from the body of the jack member. The stabilising attachment may be securable to the body of the jack member in a first position and may be engageable at a second location.

Preferably in the first position, the stabilising attachment provides a section of the peripheral ground engagement surface with the jack member in the first configuration. Preferably in the second position, the stabilising attachment stabilises the body of the jack member with the wheel in the raised position. In particular, the stabilising attachment may form a wedge between the body of the jack member and the ground surface. Preferably the stabilising attachment provides a chock component which maintains the jack member in a stable position with the wheel retained on the transit surface.

Preferably the stabilising attachment is secured to the body of the jack member by releasable means. The releasable means may comprise a lug which engages with a corresponding slot provided in the body of the jack member.

The stabilising portion may comprise an articulating portion which is movable between a first position and a second position. In the first position, the articulating portion may provide the support (contact) region of the peripheral ground engaging surface with the jack member in the first configuration and the axle in the raised position. In the second position, the articulating portion may provide a stabilising member to retain the jack member in the raised position with the jack member in the second position.

The articulating portion may be pivotally connected at or adjacent to (towards) the (first end) of the body of the jack member.

The trailer jack may comprise a leveller component which may comprise a ramp portion. The trailer jack may comprise a first leveller component and a second leveller component and each leveller component may comprise a ramp portion. The trailer jack may comprise a two tier leveller.

The trailer jack may comprise a connector for securing the or each leveller to the trailer jack body.

The peripheral ground engagement surface may comprise an anti skid surface. The peripheral ground engagement surface may comprise a plurality of ribs or protrusions for engaging the ground.

The trailer jack may comprise metal and preferably is aluminium.

The axle engagement means may be provided on a detachable component. According to a second aspect of the present invention there is provided a trailer assembly comprising a trailer and a trailer jack, the trailer jack comprising a jack member comprising;

axle engagement means which is arranged to engage an axle of the trailer; a wheel transit surface for a wheel of the trailer to travel over; and

a peripheral ground engaging surface;

wherein the jack member is configurable between a first configuration and a second configuration in which, in the first configuration;

a part of the peripheral ground engaging surface comprises a supporting region which supports the jack member on a ground surface; and

the axle engagement means is arranged to engage an axle of the trailer and wherein movement of the axle engagement means in a first direction causes the axle engagement means to pivotally move relative to the supporting region and for the distance between the axle engagement means and the ground surface to increase in order to raise the axle from the ground; and

in the second configuration;

the peripheral ground engaging surface of the jack member is arranged to rest on the ground surface and a wheel of the trailer is movable up the transit surface to raise the wheel away from the ground surface from a ground position to a raised position. Preferably in the first configuration;

the axle engagement means is arranged to engage a sole axle of a single axle trailer and wherein movement of the axle engagement means in a first direction causes the axle engagement means to pivotally move relative to the supporting region and for the distance between the axle engagement means and the ground surface to increase in order to raise the single axle from the ground; and

in the second configuration;

the peripheral ground engaging surface of the jack member is arranged to rest on the ground surface and a wheel mounted on a multi-axle trailer is movable up the transit surface to raise the wheel away from the ground surface from a ground position to a raised position. Preferably, in the second configuration, a wheel mounted on a multi-axle trailer is movable up the transit surface to raise the wheel away from the ground surface from a ground position to a raised position in order to suspend a wheel mounted on another axle at a position spaced from the ground.

According to a third aspect of the present invention there is provided a method of reconfiguring a trailer jack wherein the trailer jack comprises a jack member comprising;

axle engagement means which is arranged to engage an axle of a trailer; a wheel transit surface for a wheel of a trailer to travel over; and

a peripheral ground engaging surface;

wherein the method comprises reconfiguring the trailer jack between a first configuration and a second configuration in which,

in the first configuration;

a part of the peripheral ground engaging surface comprises a supporting region which supports the jack member on a ground surface; and

the axle engagement means is arranged to engage an axle of the trailer and wherein movement of the axle engagement means in a first direction causes the axle engagement means to pivotally move relative to the supporting region and for the distance between the axle engagement means and the ground surface to increase in order to raise the axle from the ground; and

in the second configuration;

the peripheral ground engaging surface of the jack member is arranged to rest on the ground surface and a wheel of a trailer is movable up the transit surface to raise the wheel away from the ground surface from a ground position to a raised position.

Preferably the method comprises reconfiguring the trailer jack for use with a single (sole) axle trailer and also for use with a multi axle trailer. BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be further described, by way of example, and with reference to the accompany drawings, in which: Figure 1 is an exploded perspective view of a preferred embodiment of a trailer jack; Figure 2 is a perspective view of a preferred embodiment of a trailer jack in a second configuration showing one axle of a multi-axle trailer prior to raising the trailer; Figure 3 is a perspective view of a preferred embodiment of a trailer jack in a second configuration showing one axle of a multi-axle trailer in a raised position on the trailer jack and with a detachable stabilising member engaged;

Figure 4 is a perspective view a preferred embodiment of a trailer jack in a first configuration with the axle engagement means engaged with the axle of a single axle trailer in an initial position;

Figure 5 is a perspective view of a preferred embodiment of a trailer jack in a first configuration with the axle of a single axle trailer in a raised position;

Figure 6 is a perspective view of another embodiment of a trailer jack with an articulating stabilising member in a first position;

Figure 7 is a perspective view of another embodiment of a trailer jack with an articulating stabilising member in a second position;

Figure 8 is a side view of another embodiment of a trailer jack in a second configuration with a wheel from a multi-axle trailer supported thereon in a raised position and with an articulating stabilising member in a stabilising position;

Figure 9 is a perspective view of another embodiment of a trailer jack in a first configuration with an axle of a single axle trailer engaged with the trailer jack and in a raised position and with the articulating stabilising member providing a stabilising base;

Figure 10 is a perspective view of an alternative embodiment of a trailer jack in a first configuration; Figure 1 1 is a perspective view of an alternative embodiment of a trailer jack in a second configuration; and Figure 12 is a perspective view of a leveller of an alternative embodiment of a trailer jack.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention relates a trailer jack 10 having two configurations for lifting and supporting wheeled modes of transport and, in particular, for raising either a single axle trailer or a multi (dual) axle trailer.

In this specification, the term trailer jack refers to a lifting/raising device suitable for a trailer or other vehicle. One aim is to provide a single dedicated trailer jack which can be used with both single axle trailers and also dual (or multi) axle trailers. The trailer jack may be for use with any suitable trailer and, in particular, a caravan, folding camper, trailer tent etc. In a first configuration, the trailer jack 10 is arranged to engage with the sole axle of a single axle trailer. The trailer jack 10 raises the axle directly and hence the wheels mounted thereon such that a wheel can be removed and replaced. This is achieved without having to engage the trailer jack 10 at a reinforced position on the body shell of the trailer or under a dedicated position on a chassis of the trailer. Furthermore, as will be explained, the movement of the trailer jack 10 to the raised position is achieved through the movement of the trailer without the need for any manual or hydraulic lifting mechanism.

In a second configuration, the trailer jack 10 is arranged to directly raise and support of a wheel mounted on one axle of a multi-axle trailer. Once this wheel is in a raised position, a further wheel mounted on a second parallel adjacent axle will be spaced from the ground such that this wheel can be simply removed and replaced. In this configuration, the trailer jack 10 effectively provides a small ramp up which a wheel of the trailer can be moved/driven. Again, the trailer jack 10 does not involve or require any manual or hydraulic or pneumatic lifting mechanism.

As will be understood, the trailer jack 10 has a first configuration which raises and mounts the trailer by an axle, and a second configuration which mounts the trailer by an axle. Accordingly, the trailer jack 10 can be simply and easily be transferred for use with a single axle trailer or a twin axle trailers. In addition, the trailer jack 10 may serve as a jacking mechanism or a levelling device together with chock (or stabiliser) as required. This description will described two embodiments with the first embodiment having a removable stabilising member 30 and the second embodiment having an articulating stabilising member 130. As shown in Figure 1 , the trailer jack 10 has two configurations for lifting and supporting wheeled trailers with the first confirmation being shown in use in Figure 4 and Figure 5 and the second configuration being shown in use in Figure 2 and Figure 3. The trailer jack 10 comprises a trailer jack body 12 and a stabilising member 30, whereby the stabilising member is removably connected to the trailer jack body 12 through the engagement of a lug/tab or protrusion 36 in a slot or opening 34 on the defined in the trailer jack body. The opening 34 defines a slot or groove with detents, such that the protrusion 36 may be slid into the groove 34 laterally to engage the trailer jack body 12. However, other suitable releasable securement means may be utilised. The opening 34 is located in an upper concave surface 18 of the trailer jack 10.

The trailer jack 10 is primarily of a wedge shape to provide a ramp. In particular, in the preferred embodiment, the trailer jack body 12 has a convexo concave wedge-shaped profile having a second end 14 converging towards a first end 16. The trailer jack 10 thereby has an upper surface comprising a concave surface 18. This upper surface 18 provide a transit surface. The transit surface is adapted to receive a wheel 60 and to enable a wheel 60 to travel and roll over the transit surface. The trailer jack 10 comprises a peripheral ground engaging surface in the form of a convex surface 20 for contacting the ground 70 on which the trailer jack is resting. The peripheral ground engaging surface extends between the two ends 14, 16, of the trailer jack 10. The peripheral ground engaging surface provides a contact region which contacts the ground surface and, as will be described in more detail, the position and location of this contact region moves as the trailer jack 10 is operated.

The second end 14 of the trailer jack body 12 comprises axle engagement means comprising a channel or recess 22 which is arranged to receive and engage with an axle 62 of the trailer. The recess 22 is formed as a cut out section extending across the lateral width of the trailer jack 10 such that the axle can lie therein and be retained in a secure position. The recess 22 is located at or towards the second end 14 of the trailer jack 10 and, specifically, at or towards the upper end of the transit surface 18.

The channel 22 comprises retaining means in the form of fingers 24 to aid the receiving and retaining of the axle 62 in the channel. As shown in Figure 1 , the channel 22 is square in profile and is thereby especially adapted for retaining and engaging with to a corresponding square axle. However, the channel 22 is not limited to having a square profile, and may have a profile to correspond with any shaped axle, such as a round axle commonly found in trailers.

The first end 16 of the trailer jack is preferably substantially smaller (in height or depth) than the first end 14, so that, in use, the trailer jack body 12 may act as a ramp for the wheel 60 of a trailer. In particular, a wheel of a trailer is able to be driven up the ramp and this provides a smooth transition from an initial unmounted position (shown in Figure 2) to a final raised (or mounted) position (shown in Figure 3) with the wheel 60 supported on the trailer jack 10 in a raised position.

The stabilising component 30 is also preferably a generally wedge-shaped member. The stabilising component 30 has a primary end 38 converging towards a secondary end 40 to produce the overall wedge shape. The stabilising component 30 includes a lower planar surface 32 and an upper arcuate surface 44 connecting the two ends 38, 40. The upper arcuate surface 44 comprises a concave surface and is arranged, in the second configuration, to abut and engage with the convex lower surface 20 of the trailer jack body 12, as shown in Figure 3. In this position, the stabilising component 30 wedges the trailer jack body 12 into a stable position for retaining the wheel 60 of the trailer in a raised position. Slight movements of the wheel 60 will not cause the trailer jack 10 to rock and the load from the trailer is spread out over an increased base area as a result of the stabilising member 30. The stabilising member 30 also helps to stabilise the trailer jack on uneven surfaces.

The lower planar surface 32 of the stabilising component 30 is arranged to contact and abut the ground 70 when the axle of a trailer is raised using the trailer jack 10 in the first configuration, as shown in Figure 5. In particular, the stabilising component 30 is maintained in a connected position with the trailer jack body 12. The lower support surface 32 thereby provides an extended peripheral engagement surface for the trailer jack 10. In the first configuration with the axle 62 in a raised position, the stabilising component 30 supports the trailer jack body 12 in an upright position, such that the first end 14 of the trailer jack boy 12 is upwardly facing. The lower planar surface 32 of the stabilising component 30 therefore acts as an extension of the second end 16 of the trailer jack body 12. In this first configuration, the protrusion 36 is engaged with the opening 34 and maintains the stabilising component 30 secured fixed or attached to the trailer jack body 12. The engaging protrusion 36 is located on the primary end 38 of the stabilising component 30 and the engaging opening 34 is located on the concave transit surface 18 of the trailer jack body 12. Accordingly, when the stabilising component 30 is connected to the trailer jack body 12, the primary end 38 abuts the concave surface 18 of the trailer jack body 12.

The opening 34 is defined in, and positioned on, the concave surface 18 substantially closer to the first end 16 of the trailer jack body 12 than the second end 14. The stabilising component 30 is substantially smaller than the primary component and, consequently, the protrusion 36 occupies a significant portion of the primary end 38, as shown in Figure 1 .

Figure 2 and Figure 3 show how the trailer jack 10 is used to mount a wheel 60 from an initial resting/unmounted position to a raised/mounted position. The trailer jack in this second configuration has the stabilising component initially detached. Figure 2 shows the wheels 60, 61 and axle 62 of a stationary trailer unmounted, such that the wheels 60, 61 both rest on and abut (contact) the ground 70 or other ground/support surface. The trailer jack body 12 is placed on the ground 70, such that the lower convex surface 20 abuts the ground. In particular, the lower surface 20 provides a peripheral ground engaging surface which provides a contact region where the trailer jack 10 directly contacts the ground. It will be seen that this contact region moves position around the peripheral ground engaging surface as the trailer jack 10 effectively rolls or rocks on the ground as a result in movement of the wheel 60 up the transit surface 18.

The first end 16 of the trailer jack body 12 provides a lip which will abut a portion of the underside of the wheel 60, and this lip or first end 16 is aligned with the initial direction of travel of the wheel 60 onto the transit surface 18. The trailer may then be driven up (i.e. towed/pushed up by a towing vehicle) and onto the trailer jack body 12 until it reaches the mounted/raised position shown in Figure 3. In this raised position, the convex surface 20 continues to abut the ground, such that the vertex shared with the second end 14 abuts the ground 70. It can be seen that the trailer jack 10 effectively rolls over the ground and the peripheral ground engaging surface of the trailer jack 10 provides a rolling surface. This rolling surface provides a ground contact region which moves from an initial central position to a final (raised) position at which the contact region locates at or towards the second end 14 of the trailer jack 10. This rolling motion and the corresponding movement of the contact region are directly caused by the movement of the wheel 60 up the transit surface 18. In particular, the weight of the trailer which is transmitted through the wheel 60 causes the trailer jack to partially roll as this transmission point for weight moves up the ascending transit surface.

The other wheel 61 on the axle 62 is maintained in contact with the ground and this results in a single lateral side of the trailer being raised upwardly from the ground. In this raised position, the stabilising component 30 can be manually positioned under a portion of the trailer jack body 12. In particular, the stabilising component is arranged to locate under a part of the first end 16 of the trailer jack body 12 which will now be spaced from the ground. The primary end 38 of the stabilising component 30 contacts the ground 70 and the arcuate surface 44 of the stabilising component 30 abuts the convex lower surface 20 of the trailer jack body 12 and this results in the trailer jack body 12 being stabilised and immovable. Once raised/mounted, the wheel 60 effectively elevates an adjacent wheel on the same lateral side on another adjacent axle of the trailer from the ground 70. Accordingly, this adjacent wheel can be simply removed and replaced. As it will be appreciated, the trailer jack 10 is quick and easy to use and does not require the trailer to have a reinforced body shell or dedicated jacking point on the chassis. The trailer jack 10 is simply used by moving a wheel 60 of a multi-axle trailer up a ramp member and the trailer jack 10 does not include any complex lifting mechanism. The trailer jack 10 is usable in a first configuration (as shown in Figure 4 and Figure 5) in which the trailer jack 10 directly engages and raises a trailer by an axle 62 and this may particularly applicable to a trailer with single axle. The trailer jack 10 includes axle engagement means in the form of a channel 22 in the trailer jack body 12. In this first configuration, the trailer jack body is maintained connected to the stabilising component. In particular, the protrusion 36 of the stabilising component 30 is engaged and retained in the opening 34 in the trailer jack body 12.

The distance between the second end 14 and the first end 16 is defined as a trailer jack height, and the distance between the axle 62 (when the wheels are normally supporting the trailer on the ground) and the ground 70 is defined as an axle height. The axle height is smaller than (less than) the trailer jack height, such that in use, the trailer jack 10 is capable of elevating the trailer from the ground 70 by receiving the axle 62 in the channel 22.

Figure 4 and Figure 5 show how the trailer jack 10 in the first configuration may be used to raise (mount) a trailer by its axle 62 and possibly its sole axle. The trailer jack 10 is connected in order to mount the trailer. Figure 4 shows how the trailer is in the unmounted position, such that the wheels 60, 61 contact and abut the ground 70. The channel 22 receives the axle 62, while the convex surface 20 of the trailer jack body 12 abuts the ground 70, such that the first end 16 is aligned with the direction of travel of the trailer in order to raise the trailer. The vehicle may then be driven forward (in a raising direction), causing the trailer jack 10 to rotate into an upright position, shown in Figure 5. As a result of the trailer jack height being greater than the axle height, the axle 62 is elevated, causing the trailer to be positioned into a mounted/raised position (as shown in Figure 5). In this raised position, the wheel 60 trailer jack 10 may be removable and replaceable.

During the movement from the initial grounded position to the raised position, the trailer jack 10 is again arranged to roll along the peripheral ground engagement surface 20. The contact region (the interface between the trailer jack 10 and the ground 70) moves from a central position towards the first end of the trailer jack body 12. Furthermore, the trailer jack 10 may roll over (or pivot over) the interface between the first end 16 of the trailer jack body and the stabilising component 30. As mentioned above, the stabilising component 30 provides a substantially flat support surface 32 on which the trailer jack 10 (and hence the trailer) is stably supported with the near wheel in an elevated position relative to the ground.

Due to the corner created between the stabilising component 30 and the trailer jack body 12 along the peripheral ground engaging surface, a positive force is required to pivot the trailer jack 10 over this point to move the trailer back to the lowered position.

During the raising movement, the axle is forced down further into engagement with the axle engaging channel 22 and this ensures that the trailer jack 10 raises the trailer efficiently. The corner or first end of the trailer jack body 12 may be initially engaged with the ground 70 to form a pivot point over which the trailer jack 10 will initially rotate. In this configuration, it can be seen that he trailer jack 10 is simply placed under the trailer and engaged with the axle 62. The trailer is then driven/towed (or pushed) forwards (or backwards) to pivot the trailer jack 10 into an upright position. This movement increase the distance between the ground contact region and the axle 62 (or axle engagement means 22) and this thereby raises the axle 62 from the ground 70. Accordingly, the trailer jack 10 thereby simply and easily raises a trailer through the geometry of the device 10 rather than through a relatively complicated lifting mechanism with moving parts.

In a further embodiment, the trailer jack 10 may not require a detachable stabilising component 30 and the stabilising component 30 described above could be simply integral (for example moulded) with the trailer jack body 12. In such an embodiment, the device would not have a removable wedge to place adjacent to the trailer jack 10 in the raised position in the second configuration (see Figure 3). However, a separate stabilising component could be used or an item (for example a rock/stone) could be found to achieve this function. Another embodiment of a trailer jack 1 10 is shown in Figures 6 to 10. The trailer jack 1 10 comprises a trailer jack body 1 12, an axle engaging channel 122 and a stabilising component 130. The trailer jack body 1 12 and channel 122 are substantially the same as in the first preferred embodiment of Figure 1 . The trailer jack body 1 12 has a second end 1 14 converging towards a first end 1 16 connected by a concave transit surface 1 18 for receiving a wheel. In addition, the trailer jack body 1 12 provides a peripheral ground engaging surface in the form of a lower convex surface 120 for contacting the ground 70. As above, the peripheral ground engaging surface provides a contact region which moves in a first direction as the trailer jack 1 10 rolls in a first direction in a first configuration towards a raised position or moves in a second direction as the trailer jack 1 10 rolls in a second direction in a second configuration towards a raised position.

A channel 122 is arranged to partially encompass (or surround) a minor circumference of a square or round axle 62. This channel 122 is located at or towards the second end 1 14. Preferably the axle engagement channel 122 is located at the vertex shared with the concave surface 1 18 and the second end 1 14. Again, the axle engagement has gripping means in the form of fingers 124 to aid the gripping of the axle 62. In this embodiment, the stabilising component 130 is an articulating stabilising component 130 that moves between a first position (as shown in Figure 9) and a second position (as shown in Figure 7 and Figure 8) to provide separate stabilising functions. The articulating stabilising component 130 remains attached to the trailer jack body 1 12.

The articulating stabilising component 130 comprises a planar member and may comprise a platform, as shown in Figures 6 to 10. The platform 130 is connected to the trailer jack body 1 12, such that the platform 130 is capable of moving from a first position/configuration to a second position/configuration. The first configuration is defined by the trailer jack 1 10 being capable of mounting the trailer by the axle 62, and the second configuration is capable of stabilising the trailer jack body 1 12 when the wheel has been mounted and supporting the vehicle by the wheel 60. It is therefore preferable for the platform 130 to be capable of rotating in a rotational direction 160 from the first configuration to the second configuration. Accordingly, the platform 130 is connected by a pivot or hinge bearing 150 at the first end 1 16 of the trailer jack body 1 12.

As shown in Figure 6, the second configuration is defined by the platform 130 initially providing an extension to the concave transit surface 1 18. The second configuration shown in Figure 7 is defined by providing an extension to the second end 1 16 of the trailer jack body 1 12 by being coplanar with the first end 1 14, such that the kit 1 10 may be stood in an upright position and supported by the platform.

In order for the platform 130 to provide an extension to the concave surface 1 18, a recess 134 is provided on the trailer jack body 1 12 on the concave transit surface 1 18. The recess 134 is adapted to receive the stabilising component 130 such that an upper surface of the platform 130 is level with the upper surface of the main transit surface 1 18. The hinge bearing 150 is located in the opening 134, and is limited orthogonally, such that in the first configuration, the platform 130 is substantially perpendicular to that in the second configuration. In use, with the trailer jack 1 10 in the second configuration, the platform initially provides an extended lip to aid the movement of the wheel 60 on to the main transit surface 1 18. As the wheel 60 continues to ascend the concave transit surface 1 18, the first end 1 16 of the trailer jack body 1 12 moves away from the ground. Eventually the wheel 60 will have moved completely over the upper surface 132 of the platform 130 whereby the platform 130 can be pivoted until the engaging edge 140 of the platform 130 can be securely engaged in the ground 70. To further increase the force of this engagement, the trailer and wheel 60 can be moved slightly back in the direction of the first end 1 16 of the trailer jack body 1 12. The wheel 60 may even be moved into contact with the platform 130 as shown in Figure 8. The trailer can be subsequently lowered by reversing the raising procedure.

The platform 130 is substantially cuboid in profile, as shown in Figure 7, and, comprises a set of planar interfaces, the platform has a primary end 138 parallel to a secondary end 140, whereby the two ends 138, 140 are substantially smaller than the connecting sides. The connecting sides provide an upper interface 132 and a lower interface 133. The upper interface is for contacting the wheel 60 in the first configuration (Figure 6) and for contacting the ground 70 in the second configuration (Figure 7), and the lower interface 133 provides the surface to which the hinge bearing 150 connects the platform 130 to the primary component 1 12. A portion of the lower interface 133 abuts the primary component within the recess 134. The hinge bearing 150 is preferably connected to a substantially central portion of the platform 130, and therefore, in the first configuration, substantially half of the lower interface 133 abuts the recess 134. The recess extends across the breadth of the concave surface 1 18, with the platform 130 having the breadth dimension of the trailer jack body 1 12. The primary end 138 of the platform 130 also abuts the trailer jack body 1 12. The secondary end 140 is for abutting the ground 70 when stabilising the trailer jack body 1 12 when mounting the wheel 60.

Figure 8 shows a trailer mounted on the trailer 1 10 by the wheel 60, and Figure 9 shows how the trailer jack 1 10 mounts the trailer by the axle 62. In mounting a trailer by the wheel, the trailer jack 1 10 is used in the second configuration, such that the wheel 60 may mount the trailer jack 1 10 as it would a ramp. Once mounted, the trailer jack 1 10 can then be stabilised into the stabilised condition as shown in Figure 8, such that the secondary end 140 of the platform 130 abuts the ground 70.

In use, with the trailer jack 1 10 in the first configuration, the trailer is raised/mounted by the axle 62 as shown in Figure 9. The stabilising platform 130 provides a (pivotable) base for the trailer jack body 1 12 to pivotally move around from a lowered position to an upright raised position. The platform 130 effectively provides a stable base around which the trailer jack body 1 10 pivots and this movement raises the axle of the trailer upwardly to an elevated position.

An alternative embodiment of a trailer jack 210 comprises a leveller 290, as shown in Figure 10, Figure 1 1 and Figure 12. The trailer jack 210 again comprises a trailer jack body 212 having an upper surface 218 providing a transit surface to enable a wheel of a twin axle trailer to be raised to an elevated position in order to replace an adjacent wheel. As the wheel travels along and up this transit surface 218, the trailer jack body 212 effectively rolls (or rocks) along the lower ground engaging surface 220 to increase the vertical position of the wheel.

As shown in Figure 10 and Figure 1 1 , the ground engaging surface 220 comprises a plurality of ribs 221 extending laterally across the trailer jack body 212. These ribs 221 provide an anti-slip surface to inhibit or prevent the trailer jack 10 from moving translationally on the supporting ground surface. This anti-slip surface may be provided by other ground engaging means such as protrusions, studs etc. The trailer jack 210 comprises an axle engagement means in the form of a recess 222 to engage an axle of a single axle trailer as previously described. The axle engagement means may be provided on a detachable component which is secured to the first end 214 of the trailer jack body 212. The first end 214 provides an engaging slot into which the component can be slidably inserted. A securement member 299 (screw, nut, bolt etc.) can then be used to secure the component in place on the first end 214 of the trailer jack 210.

The trailer jack 210 also comprises a leveller for levelling a trailer. As shown in Figure 1 1 and Figure 12, the trailer jack may provide a first leveller 294 and a second leveller 296. Accordingly, the trailer jack 210 also provides a two tier leveller for low and high levelling. The second leveller 296 can be supported on the upper surface of the first leveller 294 in order to provide a high levelling device. Alternatively the first leveller 294 (or the second leveller 296) could be used independently to provide a low levelling device. The levellers 294, 296 provide anti slip surfaces to prevent any unintended movement of a wheel and/or of the leveller 294, 296.

As shown in Figure 1 1 , the levelling devices 294, 296 are secured as part of the trailer jack 210 in a storage configuration. The two levelling devices 294, 296 may be positioned end to end with one of the devices 294, 296 being in an inverted position. The levelling devices 294, 296 have a tapered or wedge or angled face to enable a wheel to travel up to the supporting surfaces. In the storage configurations, these two angled faces are positioned directly adjacent to each other. The trailer jack 210 includes a connector 298 which locates on and engages with the upper surface 218 of the trailer jack 218. In particular, the upper surface 218 may include a central longitudinal (elongate) retaining groove into which a retaining element(s) of the connector 298 is retained. For example, the connector 298 may provide mushroom lugs or a substantially T-shaped profile strip which slidably engages within the retaining groove. Similarly, the connector 298 provides retaining elements (e.g. mushroom lugs or T-profiled strips) which engage within profiled grooves provided adjacent to the lateral edges of the levelling devices 294, 296. As shown in Figure 12, one face of each levelling device 294, 296 provides parallel retaining grooves into which retaining portions of the connector 298 can be relatively slidably engaged.

The first end 214 of the trailer jack body 212 and one end of the second levelling device 296 each define a retaining groove which is arranged to retain the component that provides the axle engagement recess 222. This component can be slidably attached and is secured thereto with a securement member 299. Accordingly, the trailer jack 210 is a modular device which provides a jack for raising both single axle and double (multi) axle trailers and also provides a two tier levelling device. The trailer jack 210 is modular and is all retained together in a storage configuration which also provides the configuration for single axle jacking.

The or each leveller 294, 296 may be used to stabilise the trailer jack body 212 whilst a wheel is supported on the upper surface 218 thereof.