GB2320229A

GB2320229A - A tipping trailer

Info

Publication number: GB2320229A
Application number: GB9725182A
Authority: GB
Inventors: Timothy Crowley
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-11-29
Filing date: 1997-11-28
Publication date: 1998-06-17
Anticipated expiration: 2017-11-28
Also published as: GB9725182D0; GB2320229B

Abstract

A tipping trailer (1) having: a chassis (2) having a drawbar (3) and an axle assembly, the axle assembly having an axle (4) and at least one ground-engaging wheel (19) on each end of the axle, a load carrying platform (S) having a front end and an off-loading end the platform being mounted on the chassis by a main pivotable attachment and being tiltable with respect to the chassis about the pivotal attachment, and tilting means (6) on the trailer for tilting the platform. The main pivotable attachment is located on the chassis at a position above or rearwardly of the axle, and in a tilted position, the off-loading end of the platform extends onto or close to the ground.

Description

A TIPPING TRAILER Field of the Invention The present invention relates to tipping trailers in particular those of the type which are suitable for towing by an agricultural tractor. The invention particularly relates to a tipping trailer which may be used in conveying large bales of fodder and the like, particularly round bales, wrapped or unwrapped.

Background of the Invention It is known to bale fodder such as silage, hay and the like in what are termed "round bales". These bales comprise compressed fodder in a substantially cylindrical shape and are formed in different sizes e.g. 1.2m X 1.2m or 1.5m x 1.2m (4x4 or 5x4 feet ). Such bales particularly if made of silage are too heavy to handle manually (some weigh approximately one half ton) and must be handled using machinery.

It is known to wrap round bales, in particular, of silage in a plastic film. Such a film is quite delicate and makes subsequent handling of the bale difficult as it is very easy to rip or tear the film. Grabs have been developed which can pick-up and move wrapped or unwrapped bales with minimal damage to the bale and/or the wrapping. Such grabs may be fitted to a front loader of the three point linkage of an agricultural tractor.

As it is most usual to be able to carry only up to three bales on a tractor fitted with such grabs it is desirable to load the bales onto a trailer so as to transport them to a desired location e.g. from a field to a farm yard. For wrapped bales it may be desirable to transport them to another site for wrapping. A trailer can usually accommodate upwards of five or six bales. Such transport can be quite tedious and time consuming however as firstly a grab must be used to both load and unload the bales from the trailer. This is due to the fact that as the bales (wrapped or unwrapped) are quite delicate they may not be dumped from an ordinary tipping agricultural trailer. Such tipping usually causes damage to the wrapping of the wrapped bales e.g.

by perforation of the wrapping by the surface on which it lands, stronger fibres in the fodder being forced through the plastic on impact etc. Where a bale is not wrapped, unloading by tipping from a trailer can cause the bale to permanently deform on impact under its own weight. Furthermore the bales can burst as the twine or string which holds the bale together can snap due to pressure on impact, from the deforming bale. Deformation of the bale leads to problems with subsequent handling as the bale may be flat on one side, and thus prove difficult to stack. Wrapping machines which rotate the bale rely on its symmetry for turning the bale for wrapping. Grabs also rely on the symmetry of the bale for handling. A flat sided bale may not be properly wrapped by the machine as rotation may pose difficult.

Wrapping relies on tensile strength in the film wrapped about the bale to hold the film in place. A deformed bale may not have the desired capacity to hold the film in the required position. Thus where bales are transported and unloaded by a conventional tipping trailer before wrapping the above problems will be encountered.

The tractor which tows the trailer must either be equipped with a grab, in which case it must be disconnected from the trailer to load it, reconnected to the trailer to tow the trailer to the desired location once loaded, and unhitched at the destination for unloading of the bales, or a second tractor having a grab must be used. If a second tractor is used, there must also be a second driver, to drive the second tractor between the loading and unloading sites.

US patent No. 4,930,964 describes a self-loading trailer for round bales which also unloads the bales. The trailer is very complex in design and is thus relatively expensive to make. Furthermore the bales are unloaded one by one from a series of trays in which they have been held, requiring a multiplicity of operating steps. The trailer is especially adapted for carrying round bales and is not particularly suitable for carrying other loads.

Obiect of the Invention It is an object of the invention to provide a tipping trailer which may be used to unload round bales, in particular wrapped bales, without damage to the bales or their wrapping, while retaining the trailer in a configuration which is suitable for carrying other loads.

Summary of the Invention The present invention provides a tipping trailer comprising (a) a chassis having a drawbar and an axle assembly, the axle assembly comprising an axle and at least one ground engaging wheel on each end of the axle; (b) a load carrying platform having a front end and an off-loading end, the platform being mounted on the chassis by a main pivotal attachment and being tiltable with respect to the chassis about the pivotal attachment; and (c) means for tilting the platform characterized in that the main pivotal attachment is located on the chassis at a position above, at, or rearwardly of the axle, and in that, in a tilted position, the off-loading end of the platform extends onto or close to the ground. The term "close to the ground" refers to the off-loading end of the trailer being within 3 feet, more suitably within 2 feet, preferably not greater than 1.5 feet, more preferably not greater than 1 foot from the ground.

Suitably the main pivotal attachment is itself pivotably attached to the chassis by a displacement pivot. This allows the platform to extend substantially closer to the ground on tipping of the trailer than would otherwise be possible. In a preferred arrangement the displacement of the main pivot at attachment takes place in the direction toward the front end of the platform. This effectively lowers the off-loading end of the platform so as to be closer to the ground.

It also allows both vertical and horizontal displacement of the main pivotal attachment relative to the platform. Suitably the main pivotal attachment attaches the platform to the axle so that the platform is tiltable by pivotal movement of the axle relative to the wheels. This avoids the necessity to provide a main pivot for the platform elsewhere on the trailer, and allows quite a low centre of gravity for the trailer which creates greater stability of the loaded trailer in the tipping position. Furthermore this arrangement allows the platform to extend onto or close to the ground in the tilted position, while the angle at which the platform is tilted remains relatively small.

Suitably the axle assembly further comprises an arm attached to the axle, the axle being substantially in the same horizontal plane as the drawbar in the load carrying position, the arm extending between the axle and the drawbar and being pivotably attached to an end of the drawbar to form a displacement pivot wherein on tilting of the platform the drawbar is raised relative to the axler and the axle moves to a position closer to the end of the chassis.

A mechanism may be provided to releasably secure the trailer in the load carrying position. Suitably the mechanism comprises a stop which is preferably fitted to the underside of the platform. The stop prevents relative motion of the drawbar and axle in the load carrying position.

This allows a simple pivot or hinge mechanism to be used to engage the stop. If desired a locking mechanism may be provided to lock the trailer in the load-carrying position. In a preferred embodiment the means for tilting the platform actuates the mechanism to releasably secure the platform in place. In this embodiment the main pivotal attachment is free to move about the displacement pivot when the platform is in a tilted position, but is held in a locked position when the platform is in the lowered position.

The main pivotal attachment may be located on the end of the chassis distal the front of the trailer. This allows the platform to be placed low to the chassis without abutting the chassis on tilting.

In one embodiment one end of the drawbar is pivotably attached to the platform at a position intermediate the axle and the front end of the platform. This allows the drawbar to tilt on tilting of the trailer.

The drawbar and platform open away from each other in a jaw-like fashion, about a common pivot.

In a more preferred embodiment the trailer further comprises a tailgate which is displaceable between a closed position where it acts to retain a load carried on the platform and an open position where it provides a ramp for off-loading. In particular the combination of the low main pivot on the trailer relative to the platform together with the ramp formed by the tail gate provides a gentle sloping surface from which such loads as wrapped or unwrapped round bales may be off loaded by tipping without causing damage to the bales or to the wrapping.

Suitably the tailgate is automatically releasable from a closed position to an open position by a release mechanism on the trailer on tilting the platform. This avoids the necessity for an operator of the trailer to open the tailgate.

The trailer may have an extended drawbar which allows a grab etc.

to be mounted on the three-point linkage of the trailer without interfering with the trailer when towed.

The trailer may comprise an abutment surface disposed at an angle to the platform to contact the ground in a tilted position of the platform. This stabilised the trailer on tipping.

The invention extends to a tipping trailer as described herein with reference to the accompanying drawings.

Brief Description of the Drawings Figure 1 is a side view, part sectional, of a trailer of the invention in its loaded configuration.

Figure 2 is a side view, part sectional, of the trailer of Figure 1 in the tilted or off-loading position.

Figure 3 is a end view of the trailer of Figure 1.

Figure 4 is an exploded sectional view of the pivot mechanism of the trailer of Figure 1 in its loaded configuration.

Figure 5 is an exploded sectional view of the trailer as shown in Figure 2 in its off-loading position; and Figure 6 is an exploded view of the pivot mechanism of the trailer of Figure 1.

Figure 7 shows a side view of an alternative embodiment of the trailer of the invention.

Figure 8 shows a side view (third embodiment of the trailer of the invention.

Figure 9 shows a side view of a fourth embodiment of the trailer of the invention with its wheels removed.

Figure 10 shows a rear view of a trailer of the invention having an automatically releasable tailgate.

Figure 11 is a part side sectional view of the trailer of Figure 10.

Figure 12 is a schematic representation of a release mechanism of a tailgate for the trailer in the closed position.

Figure 13 is a schematic representation of a release mechanism of a tailgate for the trailer in the open position.

Detailed Description of the Preferred Embodiments With reference to the drawings the device of the invention will now be described in more detail.

The trailer generally designated 1 comprises a chassis 2. The chassis 2 has a drawbar 3 which extends along the chassis 2 to an axle 4. From the perspective of Figure 6 it can be seen that the drawbar 3 comprises two parallel arms which meet the axle 4 at a distance apart from each other. A load carrying bed or platform 5 is mounted on the chassis 2. The term "load carrying" is used herein to describe the ability of the platform 5 to receive and carry a load.

The trailer 1 is a tipping trailer. The tipping action is actuated by a hydraulic ram 6 which extends between the chassis 2 and the platform 5. The hydraulic ram 6 is actuated by hydraulic fluid pumped through a line 7 from an agricultural tractor (not shown). Such a tipping mechanism and other tipping mechanisms are well known.

As can be seen from Figure 1 the trailer 1 is shown loaded with a number of round bales 8 positioned on the platform 5. A front panel 9 on the front end of the trailer and a releasable tailgate 10 on the off-loading end of the trailer retain the bales 8 in position during transport.

With reference to Figure 2 the trailer 1 is shown in its off-load or tipped configuration. The hydraulic ram 6 has been actuated by oil pressure from an agricultural tractor and has extended thus tilting the platform 5 of the trailer. The releasable tailgate 10 has been lowered and provides an off-ramp for the bales as they roll off the trailer. As can be seen in Figure 2 the underside or under carriage 11 of the platform 5 contacts the ground surface 13. In particular a rest portion 12 which is formed at an angle to the underside 11 of the platform 5 provides a surface on the platform 5 which abuts the ground surface 13. The angle of the rest portion 12 is so as to be parallel with respect to the ground surface 13 in the tipped position. The ramp 10 acts as on off-ramp as can be seen from Figure 2 providing a gently sloping surface for the bales 8 to roll on to the ground surface 13.

With reference to Figure 3 a pair of guides 14 are provided on the platform 5 which guide the platform relative to the drawbar 3, during tipping and lowering of platform 5. This prevents displacement to the side of the platform 5 relative to the chassis 2.

With reference to Figures 4 to 6 the drawbar 3 is attached to the arms or axle 4 by a pair of arms or plates 15. The plates 15 extends outwardly from the axle 4 and are connected to drawbar 3 via a pin 16 which extends through plates 15 and both arms of drawbar 3.

A stop 17 is provided on the underside 11 of the platform 5. The stop 17 is attached to a bracket mount 18. The bracket mount 18 attaches the stop 17 to the axle 4. As can be seen from Figure 4 the bracket mount 18 and the stop 17 provide an arrangement whereby the drawbar 3 is locked or held in a rigid position relative to the platform 5. Weight on platform 5 helps to maintain this position. In this position the axle 4 and drawbar 3 are substantially in the same horizontal plane.

As shown in Figure 5 when the platform 5 is tipped the stop 17 moves out of contact with the drawbar 3 and the relatively fixed position of the axle 4 and the drawbar 3 is no longer maintained. Axle 4 rotates providing a main pivot about which the platform 5 may be tilted. The stop 17 no longer abuts the drawbar 3 and as the angle of tipping is increased even further the axle 4 then becomes free to rotate relative to the drawbar 3 about pin 16 between the drawbar 3 and plate 15. The tipping action thus causes two relative movements of the axle 4 and drawbar 3. Firstly the axle 4 rotates about its own longitudinal axis providing a main pivot about which the platform is titled. Secondly drawbar 3 is displaced with respect to the axle 4, by motion about the pivot pin 16. The net result of this motion is that the drawbar 3 may be positioned at a higher elevation relative to the axle 4 so that a greater angle of inclination of the platform 5 may be achieved while the platform is moved closer to the ground. Previously it may have been necessary to raise the pivot point of the tipping platform to achieve a greater inclination of the surface of the platform. Axle 4 rotates relative to the wheels 19 of the trailer 1 providing a pivot mechanism for tipping the platform 5. The tipping action causes the wheels 19 and axle 14 to move forward relative to the off-loading end of the platform.

The mounting bracket 18 is shown in more detail in Figure 6.

The positioning of the axle 4 relative to the platform 5 is important. The wheel should be positioned so as to allow a slope of less than 600 and preferably less than 450 from the horizontal when the platform 5 abuts the ground 13. Though for other more robust loads the platform 5 may be capable of being elevated to higher angles. The simple pivot system of the invention allows the platform 5 to be located at a relatively low level to the ground 13. This in turn provides less of a fall or drop for bales located on the platform 5 when being unloaded. If desired however the tailgate 10 may be retained in a closed position until the platform 5 is in its fully tipped position. The gate can then be opened either manually or by a hydraulic ram to allow the bales to roll off gently. The bales do not therefore drop or fall off the trailer and the likelihood of damage to the bales or if wrapped and/or their wrapping is greatly reduced.

The drawbar 3 can be extended so that a grab or other such device can be located on the three point linkage of a tractor for towing the trailer without interfering with the trailer 1.

Figure 7 shows an alternative trailer 1 comprising a chassis 2 and a drawbar 3. A wheel 19 is provided on each side of an axle fitted to the trailer 1. The trailer 1 is a tipping trailer, having a platform 5 which is rotatable about a pivot 20 by a hydraulic ram. The trailer 1 is shown in the tilted position in Figure 7. A front portion 9 is provided on the front end of the load carrying platform 5, to stop round bales from rolling off the trailer. A tailgate 10 is also provided (shown in the closed position in Figure 5) to hold the bales from rolling off the off-loading end of the trailer. As can be seen from Figure 7 the pivot 20 is positioned rearwardly of the axle 4 and at the end of the drawbar 3 distal the drawing hitch 21. In the tilted position of Figure 7 the load carrying platform abuts the ground. In particular the bottom or underside 22 of the platform is shaped so as to rest on the ground. There is thus no drop between the off-loading end of the trailer on the ground. The tailgate 10 may function as an off-loading ramp when in the open position. This allows for gentle unloading of round bales on tipping the trailer.

Figure 8 shows a trailer similar to that shown in Figure 7 (with the wheels 19 removed). The trailer is on a support 22 (to show its normal elevation from the ground). As can be seen from Figure 8 the pivot 20 about which platform 5 may be tilted by hydraulic ram 6, is positioned almost directly above the axle 4, on the drawbar 3. The trailer 1 has a ground engaging surface 22, and a tailgate 10 as described for Figure 7. The axle 4 is located at the distal end of the drawbar 3, which allows for maximum tilting of the platform 5 while keeping the end of the platform 5 close to the ground. Again the platform 5 contacts the ground in a fully raised position of the platform.

A third embodiment is shown in Figure 9. In this embodiment the drawbar 3 is pivotably attached to the underside of the platform 5 at a pivot 24 disposed at a position between the axle 4 and the front end 25 of the platform 5. The hydraulic ram 6 is attached to the drawbar 3 at a pivot 26 positioned on the drawbar at a position forward of the pivot 24. In this embodiment the platform 25 is pivotably attached to the axle 4 so that the platform tilts about the platform 5. Indeed the platform 5 may and the axle 4 pivot together on the wheels 19 thus removing the necessity to have a further pivotable attachment between the axle and the platform 5. The trailer is shown in the tilted position in Figure 9. In this embodiment it can be seen that the drawbar 3 is tilted by the action of the hydraulic ram 6. The platform 5 and the drawbar 3 open away from each other about the pivot 24 with a jaw-like action.

It will be noted that in the above embodiments of the trailer of the invention the trailer 1, the platform 5 is attached directly to the pivot on the drawbar 3 to avoid unnecessary raising of the height of the platform above the ground.

An automatic releasable tailgate mechanism is shown in Figures 10 to 13 inclusively. The tailgate 10 extends across the rear of the trailer 1 and is pivotable about the axis indicated by the line A-A as it is attached to the rear of the trailer on the end of platform 5 by hinges 30. The tailgate 10 has two legs 31 which depend from the tailgate 10 extending to a position below the platform or bed 5 of the trailer. A locking cylindrical bar 32 is located on the trailer. The locking bar 32 is pivotable and has two stops 33 one on each end which project from the locking bar 32. In a closed position each stop 33 engages one of legs 31 of the tailgate, locking the tailgate closed (Figure 12). The locking bar 32 is attached to an upright member 34 located on the drawbar 3 of the trailer by an elongate rod 35. On tilting of the platform 5 (Figure 13) the upright 34 remains stationary holding the loading rod 32 stationary relative to the platform (the position shown in Figure 12). As the platform 5 tilts the relative movement of platform and the locking bar 32 moves the stops 30 out at contact with the legs 31 of the tailgate 10. The tailgate is then free to move about the axis A. The legs 31 can rotate to a position beneath the platform 5. A coiled spring 36 is located about the locking bar 32 to bias the tailgate 10 towards the closed position. The locking mechanism is automatically opened and there is no necessity for the operator of an agricultural tractor to which the trailer is attached to operate any release mechanism. Tipping of the trailer will automatically open the tailgate 10. Lowering the trailer causes the mechanism above to reverse, locking the tailboard in place once more.

The weight of the load being off-loaded by tipping the trailer ensures that the tailgate is pushed to the open position against the resilient bias of the spring 36 toward the closed position.

Claims

1. A tipping trailer comprising: (a) a chassis having a drawbar and an axle assembly, the axle assembly comprising an axle and at least one ground-engaging wheel on each end of the axle, (b) a load carrying platform having a front end and an off-loading end the platform being mounted on the chassis by a main pivotal attachment and being tiltable with respect to the chassis about the pivotal attachment, and (c) tilting means on the trailer for tilting the platform; characterised in that the main pivotal attachment is located on the chassis at a position above, at, or rearwardly of the axle, and in that, in a tilted position, the off-loading end of the platform extends onto or close to the ground.

2. A trailer according to claim 1 wherein the main pivotal attachment is itself pivotably attached to the chassis by a displacement pivot.

3. A trailer according to claim 1 or 2 wherein the main pivotable attachment attaches the platform to the axle, so that the platform is tiltable by pivotal movement of the axle relative to the wheels.

4. A trailer according to claim 3 wherein the axle assembly further comprises an arm attached to the axle, the axle being substantially in the same horizontal plane as the drawbar in the load carrying position, the arm extending between the axle and the drawbar and being pivotably attached to an end of the drawbar to form a displacement pivot, wherein on tilting of the platform the drawbar is raised relative to the axle, and the axle moves to a position closer to the end of the chassis.

5. A trailer according to claim 3 or 4 wherein the main pivotal attachment is free to move about the displacement pivot when the platform is in a tilted position, but is held in a locked position when the platform is in a lowered position.

6. A trailer according to any preceding claims wherein the main pivotal attachment is positioned on the end of the chassis distal the front of the trailer.

7. A trailer according to any preceding claim wherein one end of the drawbar is pivotably attached to the platform at a position intermediate the axle and the front end of the platform.

8. A trailer according to any one of claims 1 to 7 wherein the trailer comprises a tailgate located at the off-loading end of the platform, the tailgate being automatically releasable from a closed position to an open position by a release mechanism on the trailer on tilting of the platform.

9. A trailer according to any one of claims 1 to 7 wherein the trailer further comprises a tailgate at the off-loading end of the platform, the tailgate forming an off-loading ramp when in an open position, in a tilted position of the platform.

10. A trailer according to any preceding claim when the platform further comprises an abutment surface disposed at an angle to the platform to contact the ground in a tilted position of the platform.