WO1990011204A1

WO1990011204A1 - Dump apparatus

Info

Publication number: WO1990011204A1
Application number: PCT/AU1990/000111
Authority: WO
Inventors: Alan Leslie Keith
Original assignee: TROLTIP AUSTRALIA Pty Ltd; Marketmont Pty Ltd
Current assignee: TROLTIP AUSTRALIA Pty Ltd; Marketmont Pty Ltd
Priority date: 1989-03-17
Filing date: 1990-03-19
Publication date: 1990-10-04
Anticipated expiration: 1991-09-17

Abstract

A removable dump apparatus (41) for a vehicle, the apparatus including a dump box (42), a base (44) and an inflatable bag (17), a pivotal coupling (43) between the base (44) and the dump box (42) to constrain movement of the dump box to an arc, the inflatable bag (17) being located between the base (44) and the dump box (42) and being in load transmitting engagement with the base (44) and the dump box (42), the bag (17) having a side wall (18) and opposed end walls (19, 20) and when inflated assumes an elongate tapered shape.

Description

TECHNICAL FIELD OF THE INVENTION THIS INVENTION relates to a removable dump apparatus for a vehicle such as a utility truck- pickup or trailer that can be used to convert the vehicle into a dump vehicle.

BACKGROUND ART U.S. Patent No. 3,659,899 describes a removable dump box assembly that can be located in the rear of a utility truck or pickup. The assembly includes an inflatable concertina type bag mounted to the peripheral lower edge of a dump box, the bag is used to pivot the dump box when inflated by the exhaust from the vehicle. The type of bag used in this assembly limits the lift angle and the dump assembly design limit the capacity of the dump box to substantially less than the capacity of the utility truck or pickup^'. In addition, side struts are required to provide orderly inflation and deflation of the bag.

OUTLINE OF THE INVENTION

It is a principle object of the present invention to provide a removable dump apparatus for a vehicle which alleviates at least to some degree the problems of the prior art.

In one aspect, the invention resides in a removable dump apparatus for a vehicle including a dump box, a base and an inflatable bag, a pivotal coupling between the base and the dump box to constrain movement of the dump box to an arc, the inflatable bag being located between the base and the dump box and being in load transmitting engagement with the base and the dump box in order to pivot the dump box relative to the base, the bag having a side wall and opposed end walls and when inflated assumes an elongate tapered shape. Preferably, the bag has a continuously diminishing transverse cross-section throughout at least the majority of its height in a direction from the base to the dump box.

In another aspect, the invention resides in a removable dump box assembly for a vehicle, the dump box assembly including a dump box pivotally connected to a base and an inflatable bag located between the base and the dump box to pivot the dump box relative to the base, the dump box having a bottom and an upstanding side wall, the side wall having at least in part a divergent wall section angled to an adjacent wall section, the adjacent wall section bridging between the divergent wall section and the bottom of the dump box so that the dump box is narrowest adjacent the bottom.

The dump box can include a subframe supporting the bottom of the dump box. The subframe can support part of or the whole bottom. The dump box or subframe can include wheels or casters to facilitate locating the dump apparatus onto a vehicle. Where the dump apparatus is being used in a pickup or utility truck the side walls of the dump box are preferably designed so that the side walls extend so that free edge of each side wall is located outwardly and above of the free edge of the pickup or utility truck side walls. The divergent wall section and the adjacent wall section are preferably configured to provide clearance for the wheel wells of the pickup or utility truck. A tailgate or other closure can be mounted adjacent an end wall of the dump box.

The base can be of any suitable form to evenly distribute the load carried by the dump box and can be formed in part by a sheet of metal or other material or can be formed from elongate frame members formed into a base frame. The base and the dump box can have peripheral frame members which overlay when the bag is deflated in order to provide clearance for the bag between the base and the dump box. The area covered by the base can be the same as or less than the area covered by the bottom of the dump box. Alternatively, a plurality of spacers fixed to either the dump box, the dtimp box frame or the base or the base frame can abut to provide clearance for the deflated bag.

The inflatable bag preferably includes spaced load engaging surfaces and can be positioned in load transmitting engagement with the base and the dump box by either directly or indirectly securing the respective load engaging surfaces to the base and the dump box. Where the load engaging surfaces are indirectly secured, it is preferable to use fixed load transmitting plates mounted to either the dump box and base or to their respective frame members.

The inflatable bag can be made from any suitable air tight material but is preferably made from a reinforced PVC or other flexible plastics or vinyl type material.

The reinforcement preferably extends in at least two directions such that during inflation and deflation of the bag, the resultant tension in the side wall in the direction between the load engaging surfaces is substantially in the direction of travel of the load engaging surfaces.

When inflated, the bag can be of any desired shape such as generally cone shaped, frusto-conical, pyramidal or it can be other shapes with continuously diminishing transverse cross-sections in the direction toward one of the load engaging surfaces. Advantageously, the bag assumes an oblique cone-like shape when fully inflated.

The side wall of the inflatable bag is preferably made from a side wall blank of flexible material, each end wall is preferably made from an end wall blank of flexible material, the side wall blank when laid out flat having opposed neck sections and opposed arcuate seam defining portions defining a medially bulged region between the opposed neck sections, the neck sections being joined by a longitudinally extending seam in the finished bag, the end wall blanks each having oval seam defining portions when laid out flat, the respective end wall blanks having their respective seam defining portions joined to the respective seam defining portions of the side wall by respective circumferential seams.

The load engaging surfaces can be rigid plates to which the bag end walls of the bag are fixed or can be flexible surfaces of the bag. In other words, the end walls can be fixed directly to the load. The load engaging surfaces can be planar or arcuate.

The side wall can be made from a fibre reinforced plastics, PVC or other fibre reinforced material. Where the fibres are formed as a fabric, the fibres can be of uniform or non-uniform tensile strength as long as the fibres are arranged so that their resultant tension during inflation and deflation of the bag is substantially in the direction of travel of the load engaging surfaces. It is preferable to employ a fabric having at least two sets of fibres - each set having substantially parallel fibres. The fibres of one set extending at an angle to the fibres of the other set such that the direction of travel of the load engaging surfaces is between the direction along which the fibres extend. Where the fibres are all of substantially equal tensile strength the fibres of each set extend at approximately the same angle to the desired direction of resultant tension.

The side wall can be fixed to the load engaging surfaces using any suitable fixing such as clamping rings, or tabs. Where the load engaging surfaces are flexible the side wall can be fixed to the load engaging surfaces using a suitable welding technique to form overlapping seams. The load engaging surfaces can include suitable means for fixing the bag to a load such as peripheral seams, tabs or rigid clamping rings.

It is preferable however, that the bag be formed as a completely enclosed bag where the load engaging surfaces are flexible and are secured to the side wall by welding, gluing or otherwise securing overlapping seams to provide an air tight join.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the invention can be more readily understood and be put into practical effect, reference will now be made to the accompanying drawings and wherein:

Figures 1 to 3 illustrate templates from which a preferred bag can be constructed;

Figure 4 and Figure 5 are respective side views illustrating a bag constructed using the templates of Figures 1 to 3;

Figures 6 to 9 illustrate further aspects of the bag of Figures 4 and 5;

Figures 10 to 14 illustrate a preferred dump apparatus of the present invention employing the bag of figures 1 to 9 and in which;

Figure 10 shows the bag fully inflated;

Figure 11 shows the dump apparatus of Figure 10 in part and with the bag fully deflated;

Figures 12 and 13 show detailed views of parts of the dump apparatus of Figures 10 and 11; and

Figure 14 illustrates use of the dump apparatus of Figures 10 to 13.

METHOD OF PERFORMANCE

Referring to Figure 1, there is illustrated in reduced scale a template 10 from which a side wall blank of flexible material and hence, the side wall of an inflatable bag can be constructed, Figures 2 and 3 are templates 11 and 12 from which respective end wall blanks and hence, end walls of the bag can be made. In Figures 1 to 3 the dimensions shown are in millimetres. The end walls are joined to the side wall during construction of the bag as explained below.

The material to be cut to form the blanks using the templates of Figures 1 to 3 can be any suitable commercially available reinforced air tight material such as polyester reinforced PVC. Material known under the trade names COMPLAS, ATLAS and PLASTYNE are suitable; however tests on the ATLAS and COMPLAS material indicate that the sets of fibres have different tensile strength and while these materials can be used the preferred material is PLASTYNE. In PLASTYNE material the fibres have substantially uniform tensile strength and the sets of fibres are set at 90° to each other.

For PLASTYNE material the direction at which the fibres are positioned to extend across the side wall template before the material is cut to form the blank is shown by the arrows 14 in Figure 1. Thus, the resultant tension is in the direction of arrows 14a and 14b. A margin of 50mm (shown in phantom) is left about the template to account for the overlapping joins from which the seams of the bag are made. Hence, the blank in each case includes a 50mm margin when compared to the template.

The -marginal edge portions 15 and 16 of a side wall blank constructed using template 10 can be joined using a suitable welding technique. The end wall blanks are similarly cut using templates 11 and 12 with a 50mm margin (shown in phantom) and are welded to the side wall blank at marginal edges corresponding to edges 11a and 12a of side wall blank respectively. Thus, the blanks of material are actually cut to the shapes given in phantom in Figures 1 to 3.

On inflation, the bag assumes the oblique cone-like shape with rounded ends as shown in Figures 4, 5 and 10. Referring to these figures, the inflated bag 17 comprises a continuous side wall 18 extending between spaced end walls comprising a flexible apical wall 19 and a base wall 20 which are arcuate and in this embodiment are rounded end walls. The bag is shown fixed to plywood load transmitting end plates 21 and 22 (which are usually provided with the bag as a kit) but the end walls of the bag may be fixed directly to the base 44 and dump box 42 if desired.

Referring to Figures 5 to 7, the deflation of the bag will be considered. As can be seen in Figure 5, the bag is fully inflated and the upper and lower seams 25 and 26 have adjacent folds 27 which illustrate the effect of tension on the seams between the side wall and the end walls. The folds 27 are of equal size and are evenly distributed about the seam and each fold extends in the direction of travel of the end walls. These folds indicate that the tension in the side wall 18 between the load engaging surfaces is substantially in the direction of travel of the end walls and is evenly distributed along the seam. On inflation and deflation, the bag tends not to rotate.

As the bag deflates, the apical wall 19 will move in the direction of arrow 28 while the lower front portion 29 of the bag will tend to bulb forwardly in an even fashion while the base wall 20 rolls in the direction of arrow 28a on the plate 22. As the tension is even, the bulbing action at portion 29 will also be even and bag will begin to fold inwardly about the periphery as seen in Figures 6 and 7 where the bag is illustrated partially deflated and where like numerals illustrate like features.

The bag is preferably mounted to the end plate 22 using tabs which are loosely fitted to enable the base wall 20 to roll on the end plate 22 as the bag inflates or deflates. The vector representing the resultant force applied to the tray by the bag is shown in Figure 5 as a progressively increasing arrow representing different stages of inflation. As can be seen, the vector rotates rearwardly rather than remaining vertical. Thus, as the bag inflates, force is applied more directly to the load and therefore enables a greater tipping angle to be achieved with a reduced bag capacity and a simple bag construction.

As shown in Figures 8 and 9, the end plates 21 and 22 include spaced slots 30 and 31 through which respective tabs 32 and 33 can pass to be loosely fitted and secured to the end plates using staples. A hose connection 39 enables the bag to be inflated and deflated via hose 40. Referring specifically to Figures 10 and 11 there is illustrated a dump apparatus 41 constructed according to the present invention. The dump apparatus 41 is illustrated removably mounted in the rear of a pickup or utility truck (shown in phantom) and the dump apparatus 41 includes a dump box 42 pivotally connected at 43 to a base 44, an inflatable bag 17 is located in load transmitting engagement between the base and the dump box to pivot the dump box 42 about the pivot 43 (more clearly shown in Figure 12). The dump box 42 includes an end wall 44 and upstanding side walls which each include an adjacent wall section 45 adjacent bottom wall 48 and a divergent wall section 46 angled outwardly from the adjacent wall section 45.

The dump box 42 includes a subframe 47 fixed to bottom wall 48 and the end plate 21 is fixed to the subframe 47.

The base 44 is made up of a plurality of frame members 49, spacers 50 are provided between the dump box and the base to provide clearance for the bag 17 when the bag is deflated. The spacers in this case are secured to the subframe 47 so as to abut with frame members 49 when the bag is deflated.

A removable tail gate 51 is hinged to the dump box and can be secured closed using circlips 52. When the circlips are removed the tailgate is free to pivot and need not be removed during a tipping operation (see Figures 10 and 12).

The base frame made from frame members 49 is shorter than the dump box so that wheels 53 can be used to roll the dump apparatus into a position on a vehicle. The wheels are so positioned as shown in Figure 13 that only a slight tilting of the dump apparatus is required to engage the wheels and clear the base frame from being an obstacle so that the dump box can be rolled into place as shown in figure 10 and partly in Figure 14.

A hook 54 is provided on the side wall for storing a hose (not shown) which can be connected to the exhaust pipe of the vehicle when it is desired to inflate the bag to tip the dump box.

Referring to Figures 10 and 13, as can be seen, the dump box 42 is fitted with safety chains 55 which are normally held in place by a pin and stub passing through flange 56 as shown in the inset of Figure 13. The pins must be removed to enable the dump box to be tilted.

Figure 14 shows a user about to roll the dump box assembly into the box of his utility truck and as can be seen, the free edges of the dump box are located above the free edges of the utility truck side walls.

Whilst the above has been given by way of illustrative example of the present invention, many variations and modifications thereto will be apparent to those skilled in the art without departing from the broad ambit and scope of the invention as set forth in the appended claims.

Claims

1. A removable dump apparatus for a vehicle, the apparatus including a dump box, a base and an inflatable bag, a pivotal coupling between the base and the dump box to constrain movement of the dump box to an arc, the inflatable bag being located between the base and the dump box and being in load transmitting engagement with the base and the dump box, the bag having a side wall and opposed end walls and when inflated assumes an elongate tapered shape.

2. A removable dump apparatus according to claim 1 wherein the dump box includes a bottom and an upstanding side wall, the side wall having at least in part a divergent wall section angled to an adjacent wall section, the adjacent wall section bridging between the divergent wall section and the bottom so that the dump box is narrowest adjacent the bottom.

3. A removable dump apparatus according to claim 2 wherein the dump box includes a subframe supporting the bottom of the dump box and the base comprises a base frame, spacer means between the subframe and the base frame in order to afford clearance between the dump box and the base for the deflated bag.

4. A removable dump apparatus according to claim 1 or claim 2 including spacer means between the dump box and the base to afford clearance for the deflated bag.

5. A removable dump apparatus according to claim 1 or claim 2 wherein the end walls of the bag are indirectly coupled to the base and the dump box via respective load transmitting end plates.

6. A removable dump apparatus according to claim 1 or claim 2 wherein the side wall is made from a reinforced material, the reinforcement extending in two directions such that during inflation, the resultant tension in the side wall in the direction between the end walls is substantially in the direction of travel of the end walls.

7. A removable dump apparatus according to claim 1 or claim 2 wherein the bag assumes an oblique cone-like shape when fully inflated.

8. A removable dump apparatus according to claim 7 wherein the side wall is made from a side wall blank of flexible material, each end wall being made from an end wall blank of flexible material, the side wall blank when laid out flat having opposed neck sections and opposed arcuate seam defining portions defining a medially bulged region between the opposed neck sections, the neck sections being joined by a longitudinally extending seam in the finished bag, the end wall blanks each having oval seam defining portions when laid out flat, the respective end wall blanks having their respective seam defining portions joined to the respective seam defining portions of the side wall by respective circumferential seams.

9. A removable dump apparatus according to claim 1 or claim 2 wherein the base frame is shorter than the dump box and the dump box includes wheels or rollers adjacent one end thereof, the wheels protruding beyond the base frame so that the dump apparatus can be tilted and rolled on the wheels.