GB2110607A - Device for retaining material on lorries - Google Patents

Abstract

A device for retaining material transported in an open topped container (2) by a lorry consists of a retractable grating (7) consisting of a cross-bar (8) to which are fixed spaced flexible strips (9). It is actuated by an articulated mechanism composed of two identical assemblies each comprising a link (12), a rod (16) and pins (11, 15 and 23). The mechanism is subject to and controlled by the control arms (4) of the container (2). The grating (7) covers the rear portion of the container (2) in its transport position and is retracted automatically during movements of the container to other positions. <IMAGE>

Description

SPECIFICATION Device for retaining material on lorries The invention relates to a system for retaining material transported by lorries carrying demountable open topped containers such as skips and having handling means enabling the skip to be tipped out of a transport position in which it rests horizontally on the lorry into a tipping position in which it is inclined substantially vertically on the lorry and vice-versa, and to transfer the skip, always remaining substantially horizontal during handling, from the transport position to a position resting on the ground and vice-versa.

Such lorries are equipped with self-contained handling means permitting picking up a skip from the ground, resting it on the platform of the lorry, tipping it for unloading and resting it on the ground.

Skip lorries, as they are often called, generally serve for the removal and transport of loose material and more particularly rubbish, scrap, shavings, demolition rubbish, refuse and paper, none of which require protection from the weather. The transport of these materials on public or private roads involves disadvantages or risks for other users of the roads. Indeed, as a result of the fact that the skip is open topped and comprises a discharge lip at its short side oriented towards the rear of the lorry, the material may fly away during travel or overflow via the lip and spread over the roadway.

It is the object of the invention to mitigate these disadvantages by a system for retaining transported material, which is simple in construction, inexpensive and robust, and easy to install permanently on known lorries.

According to the present invention there is provided a device for retaining material transported by a lorry comprising an open topped demountable container and handling means therefor, the device comprising a screen mounted to the lorry and movable between an operational position in which it covers the rear portion of the container and other positions in which it is released from the rear portion when the container is in a transport position, and to be in its other position when the container is in a position other than the transport position.

The control mechanism may advantageously be an articulated mechanism controlled by the means for handling the container.

Advantageously the handling means comprise, at each side of the lorry, an arm journalled at one of its ends on the chassis of the lorry and provided with a support chain on the other of its ends, the screen is mounted for pivoting about a pin connected to the arms, and the control mechanism comprises at least one rod journalled at one of its ends to the screen, and to the chassis of the lorry at the other of its ends, to form a quadrilateral linkage, with the chassis, an arm and the screen, the angle of pivoting of the screen about its pin being so fixed as to impose on the screen its operational position and its other positions depending on the position of the arms.

In this case, in the quadrilateral linkage, the lower angle formed by the rod and the screen has a value less than 1800, the rod being of a length slightly less than that of an arm and being articulated substantially at the same height as the arms, and the portion of screen comprised between the upper pivot pins of the arm and of the rod being of a length slightly less than the portion of chassis separating the lower pivot pins and of said arm and said rod.

Embodiments of the present invention will now be more particularly described by way of example and with reference to the accompanying drawings, in which: Figure 1 is a side view of the rear end of a lorry embodying the invention, and illustrating the three main positions of the container; Figure 2 is a rear view of the same lorry illustrated in the retaining position; Figure 3 is an enlarged view of a portion of Figure 2 showing in detail the left-hand portion of the control mechanism of the grating; Figure 4 is a section taken along the line IV--IV of Figure 3; Figure 5 illustrates, in a partial view, a modification of the reinforced grating and its method of fixing to the control mechanism; Figure 6 is a section taken along the line VI--VI of Figure 5; and Figure 7 illustrates, in a partial side view, the raised fixing of a grating to the control mechanism.

Referring now to the drawings, Figure 1 shows the rear portion of a lorry 1 with a removable container or skip, referenced 2 in its transport position, 2' in its tipping position and 2" in its position on the ground. The skip 2 is open topped and comprises, at its short side facing the rear of the lorry, a tipping lip 3. A pair of control arms 4 are each articulated at its lower portion at 25 on the body of the lorry. There are provided control means (not illustrated) and a pair of chains 5 hooked onto the skip 2 at 6 to permit handling thereof.

A retaining system comprises a perforated screen or grating 7 (Figure 2) which covers the upper rear portion of the skip 2 and more particularly its opening or lip 3. The purpose of the grating 7 is, during travel of the lorry, to retain the transported material to prevent it from flying away or spilling over the lip 3.

There is also provided a control mechanism for the grating 7 which is controlled by the manipulation of the arms 4. The function of the control mechanism is to apply the grating 7 against the rear portion and the lip 3 of the skip 2 when this is in the transport position, and to remove the grating 7 during the handling of the skip 2 by the arms 4.

In its preferred embodiment, the grating 7 comprises an upper horizontal cross-bar 8 (Figure 3), of which the two ends, each equipped with a small plate or flange 26 fixed by welding 50, are rigidly connected to the control mechanism.

An upper horizontal cross-bar 27 may also be constructed by the assembly of two identical U irons 28 (Figures 5 and 6), fixed by a welding bead 29 at each of their ends to a plate 30 pierced with four holes 31 serving to fix the cross-bar 27 to the control mechanism. The U irons 28 are disposed parallel to one another and symmetrically, the bases of their webs being faced to face and separated by a space serving to house metal strips 9. The webs of the U irons are pierced with a plurality of pairs of holes 32 serving to fix the metal strips 9 to the cross-bar 27.

A plurality of flexible parallel strips 9, of steel or another suitable material, are fixed in a rigid manner and spaced one from another, by one of their ends to the cross-bar 8 or 27. The fixing of the strips 9 to the cross-bar 8 may be effected by welding 33 (Figure 3), by screws or by any other suitable means. The cross-bar 27 (Figures 5 and 6) advantageously permits the fixing of the strips 9, sandwiched between the webs of the U irons 28, by bolts 34, each strip 9 being pierced at its fixing end by a pair of holes coinciding with a respective pair of holes 32 in the cross-bar 27.

The object of the spacing between the strips is to impart a certain resilience to the grating to enable it to fit the inequalities in the slope of transported material. Another object is to reduce turbulence during the travel of the lorry, which would otherwise cause light material to fly away at the sides and above the grating 7. The strips 9 (Figure 1) are preformed and, seen in profile and in the relaxed position, they have a plane portion which starts from their end fixed to the cross-bar 8 and is extended by a curved portion matching the shape of the rear portion of the skip close to the lip 3.

The free end of the strips 9 may be bent round to form a loop 35 (Figure 6) which can serve as a seating for a lower horizontal cross-bar 10 adapted to reinforce the strength of the grating 7.

One or more other additional intermediate cross bars 36, if required, may be fixed transversely to the strips 9 by welding 37 or any other suitable means. The cross-bars 10 and 36 may be rigidly connected either to the strips 9 at the ends of the grating 7 or to all the strips 9. The strips 9 may also be reinforced over their plane portion by counter strips 38 fixed in the same manner as the strips 9 at their upper end, the other end being fixed by welding 39 or by any other suitable means.

It is likewise possible to construct the grating 7 in the form of a latticework grating fixed to a frame of which the cross-bar 8 or the cross-bar 27 would be one of the constituent elements.

In its preferred embodiment, the control mechanism is composed of two identical assemblies, each assembly (Figure 3) being disposed outside a respective arm 4 and comprising a cylindrical pin 11 fixed at one end by a welding bead 40 to the head of the arm 4, and a link 12 having a cylindrical through bore 13 at its upper end, and rotatable by the bore 13 about the pin 11. It is held thereon by a lock washer 14 and a keeper pin 41 fixed to the pin 11. A cylindrical pin 1 5 is fixed by a welding bead 42 to the lower end of the link 12, on its face at the outside of the lorry. The plate 26 of the cross-bar 8 is rigidly connected to the inside of the lower face of the link 12 by screws 43 or any other suitable means.

A rod 1 6 having a cylindrical through bore 1 7 at its upper end and a cylindrical through bore 18 at its lower end, is mounted for rotation by the bore 1 7 on the pin 1 5 and is held by a lock washer 1 9 and a keeper pin 44 to the pin 1 5.

A U-shaped yoke or stirrup 20 is fixed at its base to the chassis of the lorry by welding beads 21 and is provided with two cylindrical through coaxial bores 22 in its two arms, through which is mounted a cylindrical pin 23 which also passes through the bore 18. The pin 23 is held by a washer 24 and a keeper pin 45 fixed to the pin 23.

The rod 1 6 is mounted for rotation, at its lower end, by its bore 18 on the portion of the pin 23 comprised between the two cheeks of the stirrup 20.

According to a modified form of embodiment (Figures 5, 6,7), a plate 46 of trapezoidal shape is welded onto the upper portion of the link 1 2. The parts 12 and 46 may alternatively form a unitary assembly made by machining from a single piece.

The raising of the link 12 by the plate 46 enables the fixing of the cross-bar 27 of the grating 7 to be offset upwardly by a distance of about 20 cm. The object of the arrangement is to move the cross-bar 27 away and so protect it from contact with material which may exceed the outline of the skip.

The plate 46 (Figure 5) is pierced with four holes 47 corresponding to the four holes 31 pierced in the plate 30 of the cross-bar 27. Each hole 47 comprises a cylindrical countersink 48 opening towards the outside of the plate 46. The fixing of the plate 30 to the plate 46 is effected by means of "CHC" screws and "brake" nuts 49, the head of the screws being sunk in the countersinks 48.

The operation of the device is as follows.

The retaining grating, the elements constituting one of the two portions of the control mechanism, the skip and one of the two control arms are illustrated in Figure 1 in the relative positions which they occupy according to whether the arm is in the position of rest 4, of tipping 4' and of picking up and setting down 4".

When the arm is in the position 4, the rod 1 6 occupies a position to the right (as viewed in Fig.

1) of the arm 4, and its lower pivot pin 23, which is situated at a level close to that of the tipping axis 25 of the arm, is offset towards the right in relation to the latter so that the angle , which is formed by the rod 16 and the link 12 and which has as its apex the pin 1 5, has a value lower than 1 800. The grating being in the position 7, it will be seen that its strips occupy either their resilient bearing position 9 when the skip 2 is in position on the lorry, or their relaxed position 9"' in the absence of a skip on the lorry.

When the arm tilts from the position 4 into the position 4' or 4", it exerts a thrust on the link 12 of which the resulting action -- because the value of the angle a is less than 1800 and because the offsetting of the axes 25 and 23 forces the pins 11 and 1 5 to describe the respective paths a and b has the effect of bringing the link into its position 12' or 12" and the rod into its position 16' or 16" corresponding to the retracted positions 7' or 7" of the grating.

The control mechanism of the screen which advantageously uses the motive force of the means for handling the skip, can be made at low cost because of the simplicity of the equipment used. Nevertheless. It is likewise possible to construct other control mechanisms, not subject to the means for handling the skip and controlled by any other appropriate means, for example by jacks or motors.

The retaining system, in all its positions of operation, has an overall size remaining within the limits of the outline of the lorry and of the paths described by the skip and its control arms. It can therefore be used to advantage on known lorries, without any modification of their outline. Its operation is automatic and does not require any human intervention.

Claims (11)

1. A device for retaining material transported by a lorry comprising an open topped demountable container and handling means therefor, the device comprising a screen mounted to the lorry and .movable between an operational position in which it covers the rear portion of the container and other positions in which it is released from the rear portion of the container, and a control mechanism for the screen to cause the screen to be in its operational position when the container is in a transport position, and to be in its other positions when the container is in a position other than the transport position.

2. A device as claimed in claim 1, wherein the screen is perforated.

3. A device as claimed in either claim 1 or claim 2, wherein the screen is resiliently deformable and, in its operational position, covers the rear of the container by bearing resiliently thereagainst.

4. A device as claimed in any one of claims 1 to 3, wherein the screen is a grating consisting of flexible spaced strips arranged substantially parallelly and rigidly connected, at one of their ends, to a cross-bar actuated by a control mechanism.

5. A device as claimed in any one of claims 1 to 3, wherein the screen consists of a flexible latticework carried by a frame actuated by the control mechanism.

6. A device as claimed in any one of claims 1 to 5, wherein the control mechanism for the screen an articulate mechanism controlled by the handling means.

7. A device as claimed in any one of claims 1 to 6, wherein the handling means comprise, at each side of the lorry, an arm journalled at one of its ends on the chassis of the lorry and provided with a support chain on the other of its ends, the screen is mounted for pivoting about a pin connected to the arms, and the control mechanism comprises at least one rod journalled at one of its ends to the screen, and to the chassis of the lorry at the other of its ends, to form a quadrilateral linkage, with the chassis, an arm and the screen, the angle of pivoting of the screen about its pin being so fixed as to impose on the screen its operational position and its other positions depending on the position of the arms.

8. A device as claimed in claim 7, wherein, the quadrilateral linkage, the lower angle formed by the rod and the screen has a value less than 1800, the rod being of a length slightly less than that of an arm and being articulated substantially at the same height as the arms, and the portion of screen comprised between the upper pivot pins of the arm and of the rod being of a length slightly less than the portion of chassis separating the lower pivot pins and of said arm and said rod.

9. A device as claimed in either claim 7 or claim 8, wherein the screen pivots about the pin by means of a link to which it is rigidly connected and which is journalled about the pin.

10. A device as claimed in claim 9, wherein the screen is mounted rigidly connected to the link by means of a raising plate.

11. A device for retaining material transported by a lorry substantially as described herein with reference to the accompanying drawings.