GB2594586A

GB2594586A - Method and apparatus for filling bags with a flowable solid and stacking filled bags

Info

Publication number: GB2594586A
Application number: GB2105226.1A
Authority: GB
Inventors: Hatfield Mark; Dick Geoffrey
Original assignee: ROLAWN Ltd
Current assignee: ROLAWN Ltd
Priority date: 2020-04-30
Filing date: 2021-04-13
Publication date: 2021-11-03
Anticipated expiration: 2041-04-13
Also published as: GB2594490A; GB202105226D0; GB202006332D0; GB2594586B

Abstract

Providing a platform 40 and bag 10a below the discharge end of a conveyor 16 or hopper; supporting the bag on the platform while or after the bag is being filled with material dropping from the conveyor or hopper; lowering 42 the platform while the bag is on it; placing another bag 10b above the first; supporting the second bag on the first while or after it is being filled with material dropping from the conveyor or hopper; lowering the platform. A deflector 26 may be placed between the discharge end and the FIBC 10 to deflect material towards the bags edges creating a concave upper surface to improve the balance of an FIBC above. The FIBC can be supported by hooks 24 on a frame 20 engaging its handles during filling and released onto a pallet 18 on the platform after filling.

Description

Method and apparatus for filling bags with a flowable solid and stacking filled bags

Field of the invention

The invention relates to a method and apparatus for filling bags with a flowable solid material, such as topsoil or bark mulch The invention also relates to stacking of filled bags.

Background of the invention

Delivery of products of flowable solid materials, such as soil or bark mulch to a building site, is often done using large bags as shown in Figure 1 of the accompanying drawings. Each bag 10 is made of a flexible strong fabric, such as woven polypropylene, is having four carrying handles 12 sewn to the fabric of its sides about its open mouth. Such bags may have sides of 70cm to 100cm and can be filled with material weighing as much as 1000 Kg. For this reason, they cannot be moved manually and are usually moved using a forklift truck. The truck can either engage a pallet on which a filled bag rests, or its fork can engage in the handles 12.

Conventionally, when a bag is to be filled it is placed beneath the discharge opening of a fill-hopper or conveyor. Plowable solid material is either loaded directly into the hopper or fed onto the conveyor filling the hopper from a secondary feed-hopper. This feed-hopper may contain a mixing and blending mechanism, therefore discharging a blended product onto the feed-conveyor.

An operator uses the handles 12 to keep the mouth of the bag open and at the desired level above the ground. The material discharged from the fill-hopper or conveyor tends only to form a heap at the centre of the base as it is filled. This is because some flowable solid material, such as soil, do not flow sufficiently freely to spread naturally towards the sides of the bag. To ensure that the bag is filled fully, an operator may use a rake to spread the material, by pushing it physically towards the sides and corners of the bag. The operator may also create a depression in the material in the centre of the filled bag. Once the bag has been filled it is moved from under the hopper by means of a forklift that can either engage the handles 12 or a pallet used to support the bag as it was being filled. -2 -

For storage and delivery, it is desirable to stack bags two high, i.e. one above another, to save the area needed for storage and distribution. The upper bag rests directly on the lower one and bags should not be stacked any higher as they would become unstable. To achieve the stacking, after the second bag has been filled, it is lifted by means of its handles, using a forklift truck, and positioned on a previously filled lower bag.

It will be noted from the above description of the manner in which bags are currently filled and stacked that the operation is labour intensive, requiring operators to position a bag beneath the discharge opening of the hopper and keep its mouth open, to rake the material falling into a bag from the hopper and to operate a forklift truck to remove bags from under the hopper and to stack them one above the other.

The operation is also relatively slow, because if bags are to be carried by their handles using a forklift truck, the truck driver must first position the front end of the fork near two of the handles and a separate operator must then loop each handle over the fork.

The truck driver must then advance the truck to align the front end of the fork with the other two handles for them to be looped onto the fork. Care must then also be taken to ensure that an upper bag is safely balanced on the lower one before its weight is transferred from the forklift truck to the lower bag.

Object of the invention The invention in its different aspects seeks to render the filling of large bags with a flowable solid material and the stacking of filled bags one above another less labour 25 intensive

Summary of the invention

In accordance with the present invention, there is provided a method of filling two bags with a flowable solid material and vertically stacking the filled bags, which method comprises: providing a conveyor or hopper having a discharge end from which flowable solid material is discharged to fall under gravity, providing a vertically movable platform located directly beneath the discharge end, placing a first bag beneath the discharge end, dropping flowable solid material from the conveyor or hopper into the first bag until the bag is filled, -3 -supporting the first bag on the vertically movable platform either during or after filling of the first bag, lowering the vertically movable platform with the first filled bag supported thereon, placing a second bag beneath the discharge end and above the filled first bag, dropping flowable solid material into the second bag to fill the bag, supporting the second bag on the material contained in the first bag either during or after filling of the second bag, and lowering the vertically movable platform.

In some embodiments of the invention, a deflector is placed in the path of material dropped into each bag to deflect dropped material towards the periphery of the bag, thereby causing the upper surface of the material contained in the bag to be dished. By "dished", it is meant that the upper surface of contents of the bag is concave. The bottom is of the filled upper bag tends to sag under the weight of the contents and if the surface onto which it is lowered is dished, then the upper bag is centred on the lower bag and has no tendency to topple Conveniently, a frame may be provided that is located in, or movable to, a position between the discharge end and the vertically movable platform, the frame having hooks or other means of engaging the carrying handles of a bag that is being filled to maintain the mouth of the bag open as it is being filled. Each bag may be suspended from the frame during its filling and, once the bag is full, the vertical platform may be raised to support the bag and allow the handles of the bag to be separated from the frame.

If desired, the lower of the two stacked bags may be supported on a pallet resting on the vertically movable platform.

Brief description of the drawing

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1, as earlier described, is a perspective view of a bag used for transporting flowable solid materials, and Figure 2 is a schematic diagram of machine for filling bags with a flowable solid material and stacking a pair of filled bags on a pallet. -4 -

Detailed description of the drawing

Referring now to Figure 2, an apparatus is illustrated for filling bags 10 with a flowable solid material 14 supplied by means of a conveyor 16 and stacking two filled bags 10a and 10b one above the other on a pallet 18, without the need of a forklift truck to engage the handles of either bag 10a or 10b.

The apparatus comprises a rectangular frame 20 with two parallel arms 22 each bearing two hooks 24. A mechanism (not shown) can move the frame in a direction in and fo out of the plane of the drawing and may optionally also be capable of moving it vertically.

A deflector 26 is positioned in the path of the conveyor 16. The deflector 26 is rotated by means of a motor 28 to which it is connected by way of a shaft 30.

is A vertically movable platform 40 is positioned below the discharge end of the conveyor 16 and used to support the pallet 18 and any bags resting on the pallet 18. As illustrated the platform 40 is raised and lowered by a scissor jack 42 but any hydraulic or electric lifting mechanism may alternatively be used. The top surface of the platform 40 is formed in the case of the illustrated embodiment as a roller conveyor 44.

In an operating cycle of the apparatus shown in Figure 2, the vertically movable platform 40 commences in its lowermost position and an empty pallet is slid onto it using the roller conveyor 44. At this time, the frame 20 is located behind the plane of the drawing and an operator suspends an empty bag 10 from the frame 20 by looping its handles 12 over the hooks 24 of the frame 20. While thus suspended from the frame 20, the bag 10 is moved to a position where the bag surrounds the deflector 26. With a bag 10 positioned to receive the flowable solid material 14 on the conveyor 16, the latter is operated to discharge material into the bag.

As it falls, the material impacts the deflector 26 which is rotated by the motor 28.

Upon impacting the deflector 26, at least a major proportion of the material is deflected radially outwards so that, instead of forming a heap at the base of the bag, the material is flung to reach the sides and the corners. In this way, when the bag is fifth the upper surface of its contents is dished. If desired, the frame 20 or the deflector may be movable vertically to ensure that the deflector 26 remain at a constant height above the surface of the material in the bag 10. However, in the illustrated embodiment, the frame 20 and the deflector do not move relative to one another and the deflector is maintained at a -5 -stationary level relative to the base of the bag being filled When the falling material reaches this level, the motor driving the deflector draws more current and this is taken as an indication that the bag is full Once the desired amount of material has been loaded into the bag, the platform 40 is raised and the weight of the filled bag is supported by the pallet 18, thereby releasing the tension in the handles 12 of the bag As the bag continues to be raised, the handles 12 cease to engage the hooks 24, thus allowing the frame 20 to be moved to a position behind the plane of the drawing.

While an operator suspends a new empty bag from the hooks of the frame 20, the movable platform 40 is lowered to the position shown in the drawing. The second bag 10b is now moved into a position surrounding the deflector 26 and it is in turn filled in the same way as the bag 10a, now resting on the pallet 18. Once the desired amount of material has been loaded into the second bag 10b, the platform is raised until the second bag 10b rests on and its weight is supported directly on the material contained in the bag 10a. As the surface of the material contained in the bag 10a is dished, and the bottom of the bag 10b sags in the middle, the sagging bottom of the bag 10b tends to settle in the hollow contents of the bag 10a, thereby aligning the two bags and ensuring their stability when stacked.

As with the first bag 10a, the platform can now be raised until such point as the handles 12 of the bag 10b are released from the hooks 24 and the frame 20 can be moved to the plane behind that of the drawing. Once the upper bag lOis free of the frame 20, the vertically movable platform is lowered to its starting position. In this position, either using the roller conveyor 44 or a forklift truck, the pallet supporting the two vertically stacked filled bags 10a and 10b can be moved away from the apparatus and replaced by an empty pallet in readiness for the next operating cycle.

The illustrated apparatus requires a supply of the flowable solid material to be loaded into the bags 10. In practice, the base of the lifting mechanism 42 will rest on ground at the same level as mounds of one or more materials to be loaded into the bags. It is because of the need to elevate the supply of flowable solid material that the illustrated embodiment employs a conveyor 16. Earth moving equipment is used to transfer one or more flowable solid material to be loaded into bags into a hopper that may contain a blending mechanism. Material is discharged from the hopper onto an elevating conveyor that raises the material to the level of the conveyor 16 shown in Figure 2. -6 -

If the flow-able solid material is sold by volume, then as described above a bag may be considered full when the material attains a desired height within the bag. If, however, it is sold by weight and the density of the material may vary, its weight can be determined in the illustrated embodiment by incorporation of a weighing device, such as a strain gauge or a load cell in the frame 20.

The shape of the deflector 26 can be arrived at empirically to achieve the desired distribution pattern of the flowable solid material. It can be formed as a solid shaped plate, or a plate having holes to allow some of the material to pass through. Alternatively, the lc deflector may be formed of individual blades, as an impeller.

In an embodiment of the invention not shown in the drawing, two apparatuses as shown in Figure 2 may be positioned side by side and supplied by a common conveyor that can be slid to switch between the two. In this way, during such time as bags are being is loaded onto one apparatus, the material discharge from the conveyor can be used the fill a bag in the other apparatus, thereby rendering the process of filling bags substantially continuous and avoiding the need to stop and start the discharge of material from the conveyor.

When the double-stacked filled bags on pallets are moved away from the apparatus of Figure 2 by means of a conveyor, it is possible to provide a mechanism to compress them from above, to achieve greater stability.

Additionally, the filled bags could pass through a banding or wrapping machine, to give still more stability and enable a label or brand to be added to the product. -7 -

Claims

CLAIMS1. A method of filling two bags with a flowable solid material and vertically stacking the filled bags, which method comprises providing a conveyor or hopper having a discharge end from which flowable solid material is discharged to fall under gravity, providing a vertically movable platform located directly beneath the discharge end, placing a first bag beneath the discharge end, dropping flowable solid material from the conveyor or hopper into the first bag la until the bag is filled, supporting the first bag on the vertically movable platform either during or after filling of the first bag, lowering the vertically movable platform with the first filled bag supported thereon, placing a second bag beneath the discharge end and above the filled first bag, dropping flowable solid material into the second bag to fill the bag, supporting the second bag on the material contained in the first bag either during or after filling of the second bag, and lowering the vertically movable platform.
2. A method as claimed in claim 1, which further comprises placing a deflector in the path of material dropped into each bag to deflect dropped material towards the periphery of the bag, thereby causing the upper surface of the material contained in the bag to be dished.
3 A method as claimed in claim 1 or 2, which further comprises providing a frame that is located in, or movable to, a position between the discharge end and the vertically movable platform, the frame having hooks or other means of engaging the carrying handles of a bag that is being filled to maintain the mouth of the bag open as it is being filled.
4. A method as claimed in claim 3, wherein each bag is suspended from the frame during its filling and, once the bag is full, the vertical platform is raised to support the bag and allow the handles of the bag to be separated from the frame.A method as claimed in any one of the preceding claims, wherein the lower of the two stacked bags is supported on a pallet resting on the vertically movable platform.