GB2108056A - Vehicle with a tilting load platform - Google Patents

Abstract

The load platform (11) of a lorry or trailer, especially of a breakdown vehicle, tilts and slides rearwardly until its rear edge contacts the ground. A jack (6) acts at (7) on a link (8) which is pivoted at (10) on the chassis (3) and at (9) on the platform (11). In addition, U-section rails (12) on the platform (11) run and pivot on rollers (13) freely rotatable on a fixed shaft carried by the chassis (3). Thus when the jack (6) is extended, the platform (11) tilts whilst running along the rollers (13). <IMAGE>

Description

SPECIFICATION A vehicle with a tilting load platform The present invention relates to a new type of vehicle fitted with a load platform which tilts and slides. In particular, it concerns a platform able to be tilted towards the rear of the vehicle until its rear edge comes into contact with the ground.

Such a platform may constitute the load platform located behind the cab of a lorry. It could equally well constitute the load platform of a trailer.

The vehicle according to the invention is mainly used to take on loads resting on the ground which are hoisted on to the platform when the edge of the latter is lowered to the ground.

Once the load is hoisted on to the vehicle, the platform is returned to the horizontal, that is to say, to the transport position, and the vehicle can then travel on the road carrying its load.

Such a use is frequently encountered, for example with breakdown vehicles, when it is proposed to go and pick up a vehicle which has been in an accident, or a wreck in order to carry it.

It frequently happens that after an accident the wreck can no longer run, or even that because its suspension is destroyed, its chassis platform is for practical purposes resting on the ground.

Vehicles with a tilting platform which may be used in this way to pick up and carry accident wrecks are known.

These known devices have various disadvantages, principally: -Since the rear wheels of the carrying vehicles obstruct the tilting of the platform, that latter can oniy swing through a limited angle, its rear edge not being lowered as far as the ground. In this case it is necessary to provide, at the rear of the platform, additional sliding or detachable ramps which the user must put into place manually before loading the vehicle to be carried.

-In other known vehicles the problem of the limited angle of tilt of the platform has been resolved by making this platform tilt rearwards between the rear wheels of the carrying vehicle.

The disadvantage is that the useful width of the tilting platform must be less than the distance between the rear wheels of the vehicle, which prohibits the loading of certain types of vehicle.

-Finally, in other known vehicles, a tilting false chassis is provided above the rear wheels; on this a teiescopic platform can slide. In this case the false chassis is first tilted, then the telescopic platform is moved backwards until it is lowered into contact with the ground. Such a solution entails considerable cost price and complication.

The present invention aims at avoiding these disadvantages by providing a system with a swinging and sliding platform so that the angle formed between the ground and the platform in the loading position is compatible with loading vehicles which have a very small ground clearance. In addition, the useful width of the said platform may be equal to the maximum width dimension fixed by the road regulations, whilst the methods used are at once inexpensive and have entirely automatic operation. In particular, the user can control the operations without getting out of the cab of his lorry.

A device according to the invention, intended for fitting to the chassis of a vehicle having rear wheels, comprises a tilting platform and it is characterised in that on the one hand the pivot axis of the tilting platform is constituted by a transverse shaft with rollers working in conjunction with U-section longitudinal rails fitting around these rollers, the assembly being interposed between the chassis of the vehicle and the lower face of the platform, so that the latter can both tilt around this axis and move back in relation to the chassis, whilst on the other hand, the means for tilting the platform are constituted by a link of which the upper end is pivoted around a transverse shaft located below the platform and of which the lower end is pivoted on a transverse shaft on the vehicle chassis, a tilting jack being interposed longitudinally between the said link and the front of the chassis. Thus, when the lengthening of the jack is initiated by known means, the upper pivot of the link describes a rising arc about the lower pivot carried by the chassis, this path of a rising arc being directed rearwards and so causing the simultaneous tipping of the tilting platform and its backward movement in relation to its transverse pivot shaft.

According to another characteristic of the invention, the pivot shaft with rollers is carried on the chassis of the vehicle, whilst the U-section rails constitute the side-members of the lower face of the platform to which they are fixed.

According to another characteristic of the invention, the transverse shaft with rollers is fixed to the lower face of the platform, whilst the longitudinal U-section rails are fixed to the sidemembers of the vehicle chassis.

According to another characteristic of the invention, the pivoted link is also elbowed, so that its two pivotal axes respectively below the platform and on the chassis constitute the longest side of a triangle of which the apex, formed by the pivot and thrust shaft of the jack is located above and behind this base when the assembly is in the transport position with the platform returned to the horizontal on the chassis.

Owing to this arrangement, when the platform is horizontal in the transport position, the thrust jack already has an appreciable tilt, so that when its lengthening is initiated, its thrust force is brought to bear on the link with an already large leverage, which proportionately facilitates the action of the jack in this always critical initial phase.

It will be understood that owing to this arrangement according to the invention, the device allows the use of a platform of which the upper face is both continuous and occupying all the width of the maximum dimension authorised by the road regulations, this platform being located entirely above the wheels of the carrying vehicle. On the other hand, its combined tilting and backward movement allows it to swing through a large angle whilst bringing its rear edge directly into contact with the ground. Finally, it will be noticed that all these movements may be controlled by a single jack, so that the assembly constitutes a simple and inexpensive construction.

The attached drawing, given by way of non limiting example, will allow the characteristics of the invention to be better understood.

Figure 1 is a side view giving a diagram of a lorry fitted with a platform according to the invention, the assembly being in the transport position.

Figure 2 is a similar view giving a diagram of a road trailer of which the platform is in process of being tilted.

Figure 3 corresponds to the vehicle in Figure 1 when the platform is entirely tilted, with its rear edge in contact with the ground.

Figure 4 is a perspective view with part sections showing the tilting device with a pivoted jack and link.

Figure 5 is a perspective view with a part section showing the construction of the shaft with rollers working in conjunction with U-section slide rails.

There is shown in Figure 1 a lorry 1 of which the cab 2 is fixed to a chassis 3 placed on rear wheels 4. At the front of the chassis 3 and between its side-members there is provided a pivot shaft 5 on which bears the body of a tilting jack 6. The steam of this jack, which is directed upwards and backwards with respect to the vehicle, is pivoted about a shaft 7 on a swinging link 8. The latter is preferably constituted by a frame of the kind illustrated in Figure 4, and it carries an upper transverse shaft 9 and a lower transverse shaft 10. The upper shaft 9 is fixed to the lower face of a platform 11 whilst the lower shaft 10 is carried by the chassis 3.It will be seen in Figures 1 and 4 that in a side view the link 8 is curved, the three shafts 7, 9, 10 lying at the points of a triangle of which the longest side 9, 10 is tilted forwards and upward, whilst its apex 7 is located at once above and behind this longest side.

In addition, the lower face of the platform 11 is fixed to two U-section longitudinal rails 12 of which the open sides are facing each other. Each of these rails 12 fits around a roller 13 which runs free on the corresponding end of a transverse horizontal shaft 14 fixed to the chassis 3. Thus it will be seen that the platform 11 can at the same time: swing around the shaft 14; -and move backwards in relation to this same shaft 14 by the rails 12 running on the rollers 13.

The operation is as follows: When the jack 6 starts to lengthen from the position in Figure 1, the top of the link 8 begins to travel along a path 1 5 constituted by the arc of a circle centred on the fixed shaft 10. It will be seen in Figures 1 and 2 that this arc is directed both upward and backward in relation to the extension of the jack 6. Owing to this arrangement, the resulting movement of the platform 11 is composite, namely: -on the one hand the platform 11 is tilted by swinging around the fixed shaft 14; -on the other hand it moves backwards because of the rails 12 running along the rollers 13.

Owing to this combined movement, the platform 11 can tilt through a large angle while remaining above the rear wheels 4 of the vehicle without ever touching them.

At the end of the movement the rear edge 16 of the platform 11 is in contact with the ground 17, which allows a vehicle, a wreck, or any load whatever to be hoisted conveniently on to the said platform 11.

Once the load is hoisted on to the platform, it is necessary only to retract the jack 6 to foilow the path 1 5 in the opposite direction and to return the platform 11 to the horizontal whilst making it move forward near to the cab 2 of the vehicle.

In the example shown in Figure 2, it is supposed that the vehicle is not a lorry, but a trailer of which the chassis 3 is equipped as previously described. Owing to the elbowed shape of the link 8, it will be seen that, even when the platform 11 is in the horizontal transport position (Figure 1), the jack 6 is directed almost perpendicular to the section of the link connecting the shafts 7 and 10, which applies the thrust of the jack 6 with maximum leverage in relation to the fixed shaft 10. Owing to this arrangement, the load on the jack 6 is reduced and the start of the tilting of the platform 11 is facilitated, even when the latter carries a heavy load.

Claims (7)

1. A device intended to be fitted to the chassis (3) of a vehicle provided with rear wheels (4), comprising a tilting platform (11), and characterised in that on the one hand the pivot axis of the tilting platform (1 1 ) is constituted by a transverse shaft with rollers (13) which work in conjunction with U-section longitudinal rails (12) which fit around these rollers (13), the assembly being interposed between the chassis (3) of the vehicle and the lower face of the platForm (11), so that the latter can both swing about this shaft and move backwards in relation to the chassis (3).

whilst, on the other hand, means of tilting the platform (11) are constituted by a link (8) of which the upper end is pivoted about a transverse shaft (9) situated below the platform (11) and of which the lower end is pivoted about a transverse shaft (10) on the chassis (3) of the vehicle, a tilting jack (6) being interposed longitudinally between the said link (8) and the front of the chassis (3).

2. A device according to claim 1, characterised in that when the extension of the jack (6) is begun, the upper shaft (9) of the link (8) describes a rising arc of a circle about the lower shaft (1 0) carried by the chassis (3), this path in a rising arc being directed towards the rear of the vehicle in order to cause simultaneously the swinging of the tilting platform (1 1 ) and its backward movement in relation to its transverse pivot axis (rollers 13).

3. A device according to either one of the preceding claims, characterised in that the pivot shaft with rollers (13) is carried by the chassis (3) of the vehicle whilst the U-section rails (12) form the side-members of the lower face of the platform (11) to which they are fixed.

4. A device according to either one of the claims 1 and 2, characterised in that the transverse shaft with rollers (13) is attached to the lower face of the platform (11) whilst the Usection longitudinal rails (12) are fixed to the sidemembers of the chassis (3) of the vehicle.

5. A device according to any one of the preceding claims, characterised in that the pivoted link (8) is also elbowed, so that the two pivot shafts (9) under the platform (11) and (10) on the chassis (3) form the longest side of a triangle of which the apex, represented by the pivot and thrust shaft (7) is located above and behind this side (9) (10) when the assembly is in the transport position, the platform (11) being returned to the horizontal on the chassis (3).

6. A device according to claim 5, characterised in that when the platform (11) is horizontal in the transport position, the thrust jack (6) already has a large degree of inclination from the horizontal so that when its extension is begun, its thrust strength operates on the link (8) with a large leverage.

7. A platform arrangement for a vehicle constructed and arranged Substantially as herein described, with reference td the accompanying drawings.