GB2026955A - Improvements relating to vehicle tipping trailers - Google Patents

Abstract

A trailer is designed particularly for round hay bales, carrying them on a platform (9) that can be tilted down to the rear to allow the bales to roll off. The trailer has a main chassis (1) supporting a secondary chassis (4) carrying the platform. The secondary chassis pivots at the rear of the main one and overhangs it to the rear. When level it is supported and located at several points on the main chassis forward of the pivot (5). The main chassis has two wheels (3) towards the rear with a track width greater than the platform (9) for stability. The platform has no lateral barriers for ease of loading, and a removable one at the rear for discharging bales. The rear barrier may be pivoting stanchions (16) actuated to collapse by linked members (23) which are shifted by contact with the ground as the platform tilts. <IMAGE>

Description

SPECIFICATION Improvements relating to vehicle trailers This invention relates to vehicle trailers. It is particularly concerned with farm trailers for carrying "round" hay bales.

Balers which turn out cylindrical (but known as round) hay bales have fairly recently been developed. These bales are massive, being up to six feet in diameter and six feet long; they may weigh half a ton. They have many virtues, but they do give rise to handling problems. They can be picked up individually by the front loader arms of a tractor, but it is inefficient for the tractor to take each bale individually from where it is deposited in the field to its place of storage. Therefore, as with conventional rectangular bales, it is logical to load them onto trailers.

A common approach to this problem is to make a trailer a machine in itself for loading and unloading bales. One sophisticated example is equipped with tiltable fork-lifts and a transporter to shift the raised bale, with its axis vertical, from one end of the transporter to the other, progressively making room for further bales to be lifted and loaded. While the bales are fairly stable in this attitude, it is an extravagant and complex means of transport. There is also a trailer which carries bales resting on their cylindrical surfaces, but it also has tiltable fork-lifts, which are at the rear end. The tractor is backed up to each bale to load. Reversing the trailer is difficult, especially when the view is obscured by one or more massive bales already loaded on the trailer.Because of inherent instability, this type of transporter has side barriers to retain the bale. It might be thought that ordinarytrailers would serve, but side barriers are an inconvenience, and there is a tendency for the load ing platform to 'whip'. If they are massive to match the load, they are often cumbersome, and lack man oeuvrability.

It is the aim of this invention to provide a trailer of simple but rigid construction, which does not have the complication of self-loading and which is readily unloaded.

According to the present invention there is provided a tilting trailer, particularly for round hay bales, comprising a main chassis with a draw-bar, a secondary chassis with a loading platform pivoted to the rear of the main chassis and with a substantial overhang to the rearthereof, and means acting bet ween the two chassis at their forward ends to tilt the secondary chassis with a downward slope to the rear, wherein the loading platform is equipped with a removable upright barrier at the rear end, wherein there are two wheels only mounted one each side towards the rear end of the main chassis, and with a track width greater than the width of the loading platform, and wherein the secondary chassis is positively supported and located on the main chassis at more than one zone forward of the pivot.

Preferably, the loading platform is a grid superimposed on the secondary chassis. Conveniently, the grid has longitudinal members uppermost to form rails extending fore and aft of the platform. This allows the bales to roll easily. The loading platform will generally be free of side barriers, which means that loading can readily be carried out from the side, for example by a tractor equipped with a spike on its front loader. Such a spike is impaled into the centre of an end face of the bale, which can then be raised by the front loader arms. The tractor which pulls the trailer can perform this double function, hitching and unhitching being only a moment's work. The double chassis construction and a superimposed grid give the platform great rigidity and there is negligible tendency to whip.The wide span of the wheels gives stability, and being only two, generally just to the rear of the mid-length of the loading platform, they make it a highly manoeuvrable trailer.

The rear barrier may include a stanchion assembly with a post pivotable between an upright obstructing position and a lowered, load clearing position. The post may be linked to a member that engages the ground as the secondary chassis is tilted, this causing the post to move between said two positions as the ground is progressively engaged or disengaged.

A lower end portion of the post can be received in a sleeve in its upright position, and the post can then be thrust up from the sleeve to pivot rearwardly as said member engages the ground. This sleeve provides a curved fulcrum about which the post slidably pivots.

It may be beneficial to provide spring means to assist movement of the post from the lowered to the upright position. This may be between said member and the secondary chassis, or it may be embodied in said member itself.

For a better understanding of the invention one constructional form will now be described, by way of example, with reference to the accompanying drawings in which: Figure 1 is a side elevation of a trailer according to the invention, Figure 2 is a plan view of the trailer of Figure 1, Figure 3 is a detail showing, in side elevation, an erect rear end stanchion, and Figure 4 is a vew similar to Figure 3, showing the stanchion collapsed.

The trailer has a main chassis 1 with a draw-bar 2 at its forward end, and two wheels 3 mounted one each side by a rigid suspension system towards, but not at, the rear end. A secondary chassis 4 is pivotably mounted on the main chassis 1 and overhangs it substantially to the rear.

The pivot is a transverse rod 5 spanning the rear end of the chassis 1 and supporting the secondary chassis by brackets 6. These brackets are secured to respective longitudinal beams 7, which are spanned at intervals by transverse struts 8, together forming the chassis 4. A grid 9 is superimposed on this, the grid comprising transverse bars 10 and, above them, longitudinal bars 11. The grid therefore presents an array of parallel rails running fore and aft of the The drawings originally filed were informal and the print here reproduced is taken from a later filed formal copy.

trailer, on which round hay bales, indicated in out line in Figure 1, can readily roll. At the forward and rear ends of the secondary chassis 4 there are sockets 12 to receive removable stanch ions 13.

Those at the forward end may be fixed rather than removable, but the rear ones must be capable of being cleared away in order to allow the round hay bales to roll off. An improved stanchion arrange ment for the rear end will be described later.

The tilting of the platform 9 is achieved by means of a single hydraulic ram 14 acting between the for ward end of the chassis 1 and one of the transverse struts 8 of the secondary chassis. In its lowered posi tion, the secondary chassis is located between cheek plates 15 upstanding from the side of the chassis 1, and also it rests firmly on the chassis at its extreme forward end and at the strut 8 on which the ram acts. It can be arranged that it rests on the main chassis throughout the latter's length. This gives the platform considerable support and strength, and virtually eliminates whip. Although the chassis overhangs a considerable distance to the rear of the main chassis it is rigid enough in that section. It will be seen from Figure 2 that the track width of the wheels 3 is greater than the width of the platform 9.This is an important feature, giving stability to the trailer, which can be towed quite fast over bumpy ground withoutthrowing its load of round hay bales.

The bales can be loaded to the positions shown in outline in Figure 1 by a lateral approach, impaled on a front loader spike as described above For unloading, the rear stanchions 13 are removed, the chassis 4 and the platform 9 are tilted and the bales simply roll off to the rear. After driving some distance, the rear stanchions can be trapped in the sockets 12 by the bales settling against them. Therefore instead of having simple lift-out stanch ions they may have a release mechanism that allows them to be swung away from the rearmost hay bale. The arrangement described below provides this, and also an automatic release when the upper chassis is tilted to discharge the bales.

The stanchion assembly of Figures 3 and 4 has a post or spike 16 which is received in an upright generally square section sleeve 17 secured to the end of the beam 7 by a bracket 18. The upper portion of the rear facing side of the sleeve is removed, forming a tongue 19 curving outwardly and downwardly from the upper end of the remaining lower portion of that side. The post 16 is supported in its upright position by a projection 20 on one or each side which rests on the upper rim of the sleeve 17. In this position, the lower end of the post is just clear of the bottom of the sleeve. This lower post end is coupled by a curved link 21 to a lug 22 atthe end of a downwardly bowed arm 23 whose forward end is pivoted to a lug 24 projecting down from the forward end of the bracket 18.The curve of the link, the geometry of the pivot points and the fairly loose fit of the post 16 in the sleeve 17 enable the post to be collapsed from the Figure 3 to the Figure 4 position. Generally this will be caused when the upper chassis is tilted, bringing the bow of the arm 23 into contact with the ground. As tilting is completed, the link 21 is thrust up into the sleeve and the post 16, aided perhaps by a round hay bale, topples over the curved fulcrum provided by the tongue 19. The post both pivots and slides over this fulcrum. Its free end meets the ground and a short ramp is formed between the ground and the rear end of the tilting chassis. The operation is automatic, and there is no need for the tractor driver two dismount in order to discharge the bales.

When the upper chassis 4 is levelled out again, the weight of the arm 23 and link 21 may be sufficient to lever the post 16 back into an upright attitude, whence it will slot back into the sleeve 17. This may be assisted, however, by spring action. For example, a spring could be interposed between the bracket 18 (effectively the chassis 4 itself) and the arm 23 to urge the latter downwards. Alternatively, the arm itself might be a leaf spring, firmly secured at its forward end instead of being pivoted.

It may be required to carry less than a full complement of bales. There may therefore be provision for fitting intermediate stanch ions at intervals along the platform 9.

The trailer shown is for carrying four bales. This is considered the optimum load. But it is conceivable that trailers for taking more or less bales in tandem can be constructed on the above principles. To have bales side by side on a double width platform would also be possible, but that platform would then have to be wider that the current legal limit for agricultural trailers.

Claims (15)

1. Atilting trailer, particularly for round hay bales, comprising a main chassis with a draw-bar, a secondary chassis with a loading platform pivoted to the rear of the main chassis and with a substantial overhang to the rear thereof, and means acting between the two chassis at their forward ends to tilt the secondary chassis with a downward slope to the rear, wherein the loading platform is equipped with a removable upright barrier at the rear end, wherein there are two wheels only mounted one each side towards the rear end of the main chassis, and with a track width greater that the width of the loading platform, and wherein the secondary chassis is positively supported and located on the main chassis at more than one zone forward of the pivot.

2. A trailer as claimed in claim 1, wherein the loading platform is a grid superimposed on the secondary chassis.

3. A trailer as claimed in claim 1 or 2, wherein the grid has longitudinal members uppermost to form rails extending fore and aft of the platform.

4. A trailer as claimed in claim 1, 2 or 3, wherein the loading platform is free of side barriers

5. Atrailer as claimed in any preceding claim wherein the means acting between the chassis is a single hydraulic ram.

6. Atrailer as claimed in any preceding claim, wherein the suspension is rigid.

7. Atrailer as claimed in any preceding claim, wherein the rear barrier includes a stanchion assembly with a post pivotable between an upright, obstructing position and a lowered load clearing position.

8. Atrailer as claimed in claim 7, wherein the post is linked to a member that engages the ground as the secondary chassis is tilted, this member causing the post to move between said two positions as the ground is progressively engaged or disengaged.

9. Atraileras claimed in claim 8, wherein a lower end portion of the post is received in a sleeve in its upright position, and the post is thrust up from the sleeve to pivot rearwardly as said member progressively engages the ground.

10. A trailer as claimed in claim 9, wherein the sleeve provides a curved fulcrum about which the post slidably pivots.

11. A trailer as claimed in claim 8,9 or 10, wherein spring means are provided to assist movement of the post from the lowered to the upright position.

12. Atrailer as claimed in claim 11, wherein the spring means act between said member and said secondary chassis.

13. A trailer as claimed in claim 11, wherein the spring means is embodied in said member itself.

14. Atrailer as claimed in claim 11, wherein the spring means acts between the post and the sleeve.

15. Atilting trailer substantially as hereinbefore described with reference to the accompanying drawing.