GB2060545A

GB2060545A - Bag emptying machine

Info

Publication number: GB2060545A
Application number: GB8026606A
Authority: GB
Original assignee: COMAV Srl
Current assignee: COMAV Srl
Priority date: 1979-08-23
Filing date: 1980-08-14
Publication date: 1981-05-07
Also published as: DE3031391A1; DE3031391C2; FR2463737B3; GB2060545B; IT1192800B; IT7903484A0; ES8104761A1; ES494467A0; FR2463737A1

Abstract

A conveyor 6, 6' with spikes holds a bag which is cut by a pair of rotating cutters 8, 8' along its leading end and its sides. The bottom half of the cut bag is then inverted by the conveyor while the top half is folded back onto the spikes by engagement with a rest 15. <IMAGE>

Description

SPECIFICATION Bag emptying machine This invention relates to an automatic machine for emptying bags.

It is well known that the currently available bag emptying machines cut the bag they have to empty at one end and let the contents out through shaking and/or vibration. Such machines have, however, some drawbacks. The action of shaking and/or vibration, that is supposed to free the bag of its contents, creates a large amount of dust, that is harmful for the industrial hygiene and, in the long run, even for the machine. Moreover, the components that provide this action of shaking and/or vibration are very noisy, which is another drawback for staff health.

It is also well known that, in the systems currently used, there is aiways a certain residual amount of the contents that is wasted or that requires manual operation to be recovered.

The present invention provides an automatic bag emptying machine in which the feeding of the bag is carried out by a conveyor belt followed by conveyor chains that foresee lines of nails where the bag stays hooked and is kept in the correct position.

In a preferred embodiment the operation of cutting the bag is carried out by a couple of horizontal rotating dished cutters, the structure of which allows the bag to be lengthwise cut in halves along the whole periphery except part of the rear end. The cut bag is dragged further by the spiked conveyor and overturned in such a way that the upper part of the bag, by leaning on a suitable rest, allows the complete opening of the bag and the corresponding emptying. The bag, cut and emptied, is freed from the spiked conveyor by a locating bar and recovered.

The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of an automatic bag emptying machine; and Figure 2 is a fragmentary end view.

The machine has a metal casing structure 1, which has been cut away to reveal the main components. The machine can be either hand fed or fed by a conveyor belt synchronized with the machine itself. A bag, entering the machine on a conveyor belt 2 running on rollers 3 and 4, lifts a bus bar 5, connected to an electronic sensor that gives the O.K. for every further operation on the bag and supervises the entrance of the bags that follow. Moving forward on the belt 2 lengthwise to it - the bag is led to hook on to a pair of conveyor chains 6 and 6', each having a line of steel nails which pull the bag towards a cutting station while keeping it in the correct position. These chains 6 and 6' mesh on the roller 4 and slide on conveniently shaped pilot liners: the pilot liner 7 of the chain 6 is shown in Figure 1.

The bag is cut by a pair of horizontal dished cutters 8 and 8', rotating in opposite directions to each other and against the bag feeding direction; the cutters 8, 8' are keyed on respective shafts 9, 9' driven by respective motors 10. The cutting of the bag starts with the cutters 8, 8' placed adjacent each other (position A and A' in Figure 2) in such a way that the front end of the bag is completely cut; after the cutting of the front end of the bag has been completed, this end lifts a bus bar 11 connected to an electronic sensor which, by operating a hydraulic jack 12, separates the cutters (positions B and B'), the corresponding motors 10 sliding on a slide 1 3. The cutting operation proceeds along the sides of the bag to the rear end of the bag, which is only partially cut.

After the bag has been cut around the periphery in this way, the bus bar 11 goes down again, allowing the reapproaching of the cutters 8 and 8' for the cutting operation of the next bag.

The cut bag moves forward: the lower half of it, kept by the nails between the nail-holding chains 6, 6' and a slide 14, is overturned while the upper half of the bag falls down, hanging on a rest 1 5.

The further advance of the chains 6, 6' drives the lower half of the bag towards the exit, while the upper half of the bag, guided by sliding on the rest 15, is hooked to the nail-holding chains. During this stage, the contents of the bag fall into a feedbox 16.

The empty bag, lengthwise cut in half, open, and inverted, is freed from the nails of the chains 6, 6' by drawing bars 1 7 arranged obliquely to the chains, and dragged towards the exit by supporting belts 1 8. During this stage, the bag totally frees itself from its contents due to the action of gravity. Then the belts 1 8 lead the bag to ejection rollers 1 9 and 20, allowing its recovery.

The above-described automatic machine empties the bags (paper bags, polyethylene bags, cloth bags, or other bags) by freeing the bags from the product contained in them, be it powder or granules, without shaking: this action of emptying is carried out by cutting the bag and uncovering and overturning the product, therefore the bag is freed or removed from the product, instead of the usual way, i.e. the product being freed or removed from the bag. As there is no need for shaking or vibration, the machine is not noisy and creates very little dust, while leaving the smallest amount of residual product possible on the bag material.

The machine allows large hourly throughput (up to 500 bags per hour) with a low specific running cost.

1. An automatic bag emptying machine comprising a bag conveyor having a plurality of spikes which retain the bag on the conveyor and traveiling on a path such that the contents fall from the bag when it has been opened.

2. A machine as claimed in claim 1, including means for cutting the bag along its periphery into two halves which are separable so as to expose the contents of the bag.

3. A machine as claimed in claim 2, in which the two halves remain connected together at one end.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Bag emptying machine This invention relates to an automatic machine for emptying bags. It is well known that the currently available bag emptying machines cut the bag they have to empty at one end and let the contents out through shaking and/or vibration. Such machines have, however, some drawbacks. The action of shaking and/or vibration, that is supposed to free the bag of its contents, creates a large amount of dust, that is harmful for the industrial hygiene and, in the long run, even for the machine. Moreover, the components that provide this action of shaking and/or vibration are very noisy, which is another drawback for staff health. It is also well known that, in the systems currently used, there is aiways a certain residual amount of the contents that is wasted or that requires manual operation to be recovered. The present invention provides an automatic bag emptying machine in which the feeding of the bag is carried out by a conveyor belt followed by conveyor chains that foresee lines of nails where the bag stays hooked and is kept in the correct position. In a preferred embodiment the operation of cutting the bag is carried out by a couple of horizontal rotating dished cutters, the structure of which allows the bag to be lengthwise cut in halves along the whole periphery except part of the rear end. The cut bag is dragged further by the spiked conveyor and overturned in such a way that the upper part of the bag, by leaning on a suitable rest, allows the complete opening of the bag and the corresponding emptying. The bag, cut and emptied, is freed from the spiked conveyor by a locating bar and recovered. The invention will be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a side view of an automatic bag emptying machine; and Figure 2 is a fragmentary end view. The machine has a metal casing structure 1, which has been cut away to reveal the main components. The machine can be either hand fed or fed by a conveyor belt synchronized with the machine itself. A bag, entering the machine on a conveyor belt 2 running on rollers 3 and 4, lifts a bus bar 5, connected to an electronic sensor that gives the O.K. for every further operation on the bag and supervises the entrance of the bags that follow. Moving forward on the belt 2 lengthwise to it - the bag is led to hook on to a pair of conveyor chains 6 and 6', each having a line of steel nails which pull the bag towards a cutting station while keeping it in the correct position. These chains 6 and 6' mesh on the roller 4 and slide on conveniently shaped pilot liners: the pilot liner 7 of the chain 6 is shown in Figure 1. The bag is cut by a pair of horizontal dished cutters 8 and 8', rotating in opposite directions to each other and against the bag feeding direction; the cutters 8, 8' are keyed on respective shafts 9, 9' driven by respective motors 10. The cutting of the bag starts with the cutters 8, 8' placed adjacent each other (position A and A' in Figure 2) in such a way that the front end of the bag is completely cut; after the cutting of the front end of the bag has been completed, this end lifts a bus bar 11 connected to an electronic sensor which, by operating a hydraulic jack 12, separates the cutters (positions B and B'), the corresponding motors 10 sliding on a slide 1 3. The cutting operation proceeds along the sides of the bag to the rear end of the bag, which is only partially cut. After the bag has been cut around the periphery in this way, the bus bar 11 goes down again, allowing the reapproaching of the cutters 8 and 8' for the cutting operation of the next bag. The cut bag moves forward: the lower half of it, kept by the nails between the nail-holding chains 6, 6' and a slide 14, is overturned while the upper half of the bag falls down, hanging on a rest 1 5. The further advance of the chains 6, 6' drives the lower half of the bag towards the exit, while the upper half of the bag, guided by sliding on the rest 15, is hooked to the nail-holding chains. During this stage, the contents of the bag fall into a feedbox 16. The empty bag, lengthwise cut in half, open, and inverted, is freed from the nails of the chains 6, 6' by drawing bars 1 7 arranged obliquely to the chains, and dragged towards the exit by supporting belts 1 8. During this stage, the bag totally frees itself from its contents due to the action of gravity. Then the belts 1 8 lead the bag to ejection rollers 1 9 and 20, allowing its recovery. The above-described automatic machine empties the bags (paper bags, polyethylene bags, cloth bags, or other bags) by freeing the bags from the product contained in them, be it powder or granules, without shaking: this action of emptying is carried out by cutting the bag and uncovering and overturning the product, therefore the bag is freed or removed from the product, instead of the usual way, i.e. the product being freed or removed from the bag. As there is no need for shaking or vibration, the machine is not noisy and creates very little dust, while leaving the smallest amount of residual product possible on the bag material. The machine allows large hourly throughput (up to 500 bags per hour) with a low specific running cost. CLAIMS

4. A machine as claimed in claim 2 or 3, in which the cutting means comprises a pair of rotatable cutters between which the bag passes while the sides of the bag are cut, the cutters being movable towards each other to cut an end of the bag.

5. A machine as claimed in any of claims 2 to 4, in which one of the halves of the cut bag is initially retained by the spikes and the other half is subsequently automatically moved into contact with the spikes.

6. A machine as claimed in claim 5, in which the cutting means cuts the leading end of the bag on the conveyor and then the two sides of the bag, a member being provided downstream of the cutting means to restrain the said other half of the bag against forward motion, so that the said other half is folded back against the conveyor.

7. A machine as claimed in any of claims 2 to 6, in which the path of the conveyor is such that the bag is opened when travelling horizontally and is then inverted.

8. A machine as claimed in any of claims 1 to 7, including a member extending obliquely to the conveyor path so as to separate the empty bag from the conveyor.

9. An automatic bag emptying machine substantially as described herein with reference to, and as shown in, the accompanying drawings.