GB2254835A - Forming stacks of bagged material - Google Patents

Abstract

Stacking apparatus comprises a housing 10 fabricated from sheet metal including side walls (11, 12 Fig 2) and a movable floor 20 which includes a platform on which is fixed a corrugated surface 22. The surface 22 has a number of open channels 25 into which correspondingly spaced apart prongs (A, Fig 3) of fork lift truck (B, Fig 3) fit. The floor 20 is raised and lowered vertically by a hydraulic ram 50 which is activated by a switch located within easy reach of the operator. Using the method and apparatus, palletless stacks of bagged material can be assembled and placed on a trailer on which corresponding open channels are provided on its surface to accommodate the prongs of the fork lift truck. <IMAGE>

Description

METHOD AND APPARATUS FOR FORMING STACKS OF BAGGED MATERIAL The present invention relates to a method and apparatus for forming stacks of bagged material. It has particular, though not exclusive, application to forming stacks of bagged compost used in the mushroom industry.

Compost for use in the mushroom industry is supplied to growers in bags made from a plastics material.

Traditionally, these bags of compost are transported in trailers with timber railings on the sides and with the bags standing on their ends and stacked on one another.

Each bag has to be handled by a number of men loading the trailer. Furthermore, a number of men have to be available at a customers site in order to unload the trailer. A more recent method of loading these bags onto a trailer involves the building of stacks of bags onto pallets and then lifting the pallets with the stacks of bags onto the trailer, which may be open-sided The use of pallets presents a considerable advantage over the traditional method, however, it suffers from a considerable disadvantage that a stack of clean usable pallets must always be on hand. Furthermore, there is the disadvantage of having to collect empty pallets and repairing or replacing broken pallets. Also, considerable labour is still required in building up the stacks of bags on the pallets.

The object of the invention is to provide a method of and an apparatus for forming stacks of bagged material which method and apparatus alleviates the above disadvantages.

Accordingly, the present invention provides a method of forming stacks of bagged material comprising laying down a layer of bags in a housing, the housing having side walls and a floor, with the floor being movable relative to the side walls and moving the floor relative to the side walls so that the layers of bags are formed into a stack.

The invention also provides apparatus for forming a stack of bagged material, the apparatus comprising a housing having side walls and a floor which is movable relative to the side walls as layers of the stack of bags are laid down on the floor.

Advantageously, the movable floor has a generally corrugated surface having a plurality of open channels, whereby the prongs of the fork-lift truck may be inserted under the stacks of bags so as to enable the stack of bags to be lifted from the floor.

Preferably, the corrugated surface comprises a plurality of elongate channel sections spaced in a parallel apart relationship, each channel having an upper surface and two sides, with the spacing between the sides of each two contiguous channel sections providing the open channels for the receipt of the prongs of the fork-lift truck.

Advantageously, the floor is movable by means of a hydraulically operated ram, the ram being operable by a switch which is located adjacent the housing, whereby an operator standing in the housing may control the movement of the floor.

Conveniently, a corrugated surface is also provided on the floor of a transportation trailer, whereby the fork-lift truck may lay down a formed stack of bags on the trailer.

The invention will hereinafter be more particularly described with reference to the accompanying drawings which show by way of example only, one embodiment of a stack forming apparatus according to the invention; In the drawings: Figure 1 is a front view of the apparatus with one layer of bags being shown between the front wall of a housing and a corrugated floor; Figure 2 is a perspective view of the apparatus from one side showing a completed stack of bags formed on the corrugated floor which is resting on the ground; and Figure 3 is a perspective view of the apparatus from the front showing the prongs of a fort lift truck being inserted into the open channels of the corrugated floor.

Referring to the drawings, the stack forming apparatus comprises a housing 10 and a movable floor 20. The housing 10 has a front wall 11, a rear wall (not shown) and two side walls 12, all fabricated from sheet steel. The movable floor 20 includes a platform 21 on which is fixed a corrugated surface 22. Five box section channels 23 and two half box section channels 24 with closed ends are fixed on the platform 21 to provide six open channels 25 into which the correspondingly spaced apart prongs A of fork-lift truck B fit.

In the particular embodiment, the dimensions of the open channels 25 are 100 mm x 100 mm which are spaced apart at 250 mm centres. The dimensions of the half box section channels 24 are 75 mm wide x 100 mm deep and the box section channels are 150 mm wide x 100 mm deep. The overall width of the floor 20 is 1.5 m, whereas the internal width of the housing 10 is 1.4 m. This difference in dimensions is required because as a layer of bags is lowered out of the housing 10 the bags extend laterally due the contents of the bags settling.

The depth of the housing is approximately 1.2 m with the depth of the floor being approximately 1.1 m, again to allow for lateral extension of the bags. The height of the housing is approximately 600 mm. These dimensions can be varied to suit particular requirements.

The floor 20 is raised and lowered vertically by a hydraulic ram 50. Details of the hydraulic system are not shown in the drawings as such a system is a conventional hydraulic system. The hydraulic ram 50 may be activated by means of a switch located within easy reach of the operator when standing on the floor 20 or a layer of bags in the housing 10.

In use, the floor 20 is raised to engage with the housing 10 and the operator begins to lay down the bags which he removes from a bag filling machine (not shown). The bags are laid on the floor in a pattern as shown in the drawings, with alternate layers being disposed in a transverse arrangement so as to provide a stable stack.

With bags of mushroom compost, as the tops of the bags are normally not closed, they are arranged so as to be facing inwardly in the stack. With the operator standing on the bags, they are shaped so as to take up the available space within the housing. As each layer is completed, the operator lowers the floor 20 so that he continues to work at the same height relative to the bag filling machine.

When the stack is completed, the floor 20 is lowered to ground level, with sufficient clearance being provided to allow the stack to be removed from under the housing 10.

The prongs A of the fork-lift truck B are inserted into the open channels 25 of the floor 20 and in that way the stack of bags may be transported to a trailer on which corresponding open channels are provided on its surface to allow the stack to be placed on the trailer. A typical trailer could accommodate sixteen stacks, with eight on each side.

To unload the stacks at the customer's site, a similar type fork-lift truck B is used but with the second and fifth prongs B removed. Thus, when the four prong fork lifts a stack of bags, the bags located between the first and third prongs and fourth and sixth prongs respectively sag so as to form two concave shapes. These concave shapes come in contact with the ground when the fork with the stack is laid on the ground. In this way, the prongs may be withdrawn to allow the stack to rest on the ground.

Thus, it will be seen that the invention overcomes the disadvantages associated with the prior art.

It is to be understood that the invention is not limited to the specific details described above, which are given by way of example only, and that modifications and alterations are possible without departing from the scope of the invention as defined in the appended claims.

Claims (8)

CLAIMS:

1. A method of forming stacks of bagged material comprising laying down a layer of bags in a housing, the housing having side walls and a floor, with the floor being movable relative to the side walls and moving the floor relative to the side walls so that the layers of bags are formed into a stack.

2. Apparatus for forming a stack of bagged material, the apparatus comprising a housing having side walls and a floor which is movable relative to the side walls as layers of the stack of bags are laid down on the floor.

3. Apparatus as claimed in Claim 2, in which the movable floor has a generally corrugated surface having a plurality of open channels, whereby the prongs of the fork-lift truck may be inserted under the stacks of bags so as to enable the stack of bags to the lifted from the floor.

4. Apparatus as claimed in Claim 3, in which the corrugated surface comprises a plurality of elongate channel sections spaced in a parallel apart relationship, each channel having an upper surface and two sides, with the spacing between the sides of each two contiguous channel sections providing the open channels for the receipt of the prongs of the fork-lift truck.

5 Apparatus as claimed in any on of Claims 2 to 4, in which the floor is movable by means of a hydraulically operated ram, the ram being operable by a switch which is located adjacent the housing, whereby an operator standing in the housing may control the movement of the floor.

6. Apparatus as claimed in Claim 3 or Claim 4, in which a corrugated surface is also provided on the floor of a transportation trailer, whereby the fork-lift truck may lay down a formed stack of bags on the trailer.

7. A method of forming stacks of bagged material substantially as herein described with reference to the accompanying drawings.

8. Apparatus for forming a stack of bagged material substantially as herein described with reference to, and as shown in, the accompanying drawings.