GB2024765A - Device for cutting open and emptying bags - Google Patents

Abstract

A device for cutting open and emptying bags, having a support for the bags and a cutting member 9 arranged at the end of the support and a discharge opening 2 beneath the cutting member, has the support formed as a slide 3 surrounded by lateral walls and the cutting member is provided at the lower end of the slide. Various forms of cutting member with reciprocatory or circulatory drive, suction means 13-24 for dust extraction including a suction duct 21 surrounding the open top of the device, an automatic protection device 12 for the cutting member, and an empty bag chamber 26 with tying string 29 are described. <IMAGE>

Description

SPECIFICATION Device for cutting open and emptying bags The invention relates to a device for cutting open and emptying bags, having a supportforthe bags and a cutting member arranged at the end of the support and a discharge opening beneath the cutting member.

A device of this kind is already known from DE-AS 1 461 885,i.e. the German published application of that number. In this case the supports are in the form of horizontal skids and the cutting member is a circular blade which rotates in a vertical plane. The individual bags are automatically conveyed to the blade on a continuous conveyor and subsequently beaten out and ejected. That device is designed to empty several hundred bags per hour. However, in workplaces where the number of bags to be emptied is much smaller, e.g. fifty per hour, the use of such a relatively expensive device is not always justified. In such workplaces, therefore, bags are usually cut open and emptied by hand. This type of work is very arduous. The cutting open, emptying and especially the depositing and collecting of the bags is often associated with the formation of considerable amounts of dust.

It is an object of the present invention to provide a device of the kind mentioned initially above, which is considerably cheaper than the known device and which, with manual assistance, works faster than the purely manual operation and also substantially reduces the dust nuisance.

To this end, as stated in Claim 1 of the claims of this specification, the said support is formed as a slide surrounded by lateral walls and the cutting member is provided at the lower end of the slide.

The construction of the support in the form of a slide avoids the use of expensive continuous conveyors.

The housing surrounding the slide to a large degree prevents the dust from reaching the surrounding area.

Various other advantageous features are set forth in Claims 2 to 18 of the ciaims of this specification and explained as follows.

The feature of Claim 2 enables the slide to be adjusted for the particular bags to be emptied so that the bags can be conveyed to the cutting member with the least possible manual assistance.

The feature of Claim 3 ensures a stable position of the bag during the cutting process.

Particularly in the cutting zone it is important that the bag is protected from being laterally displaced.

This is achieved by the feature of Claim 4.

The feature of Claim 5 makes possible adaptation to bags of different sizes.

The feature of Claim 6 is provided for safety reasons.

Claim 7 describes a preferred embodiment of the cutting member. This produces less dust than the previously known circular cutters which rotate at fast speeds and thus produce clouds of dust.

The cutting member arrangement according to Claim 8 is particularly simple and inexpensive. It has also the advantage that the two-and-fro movement of the cutting member additionally produces a shaking movement which assists in the bag emptying process.

Depending on the bag material and the type of contents, however, the embodiment according to Claim 9 may be preferred as this makes for particularly quiet operation.

According to Claim 10 the cutting speed of the saw or other cutter can be adjusted so as to achieve a good cutwith minimum production of dust.

The feature of Claim 11 prevents the dust thrown up from being discharged into the surrounding atmosphere.

The feature of Claim 12 ensures a particularly effective suction removal of the dust.

Claim 13, particularly in conjunction with Claim 14, provides for a particularly compact mode of construction.

The feature of Claim 15 simplifies the changing of the filter.

The embodiment according to Claim 16 enables the emptied bags initially to be collected within the housing itself and subsequently to be removed as a stack. This causes less dust to be formed than when bags are being removed individually.

The removal of the stacked empty bags is made easier by the feature of Claim 17.

The ancillary apparatus described in Claim 18 makes the bundling and the dust-free removal of the bags still easier.

The invention will now be described, by way of example, with reference to the accompanying drawings which show an embodiment of the invention in a simplified manner. In the drawings: Figure 1 shows a side elevation of a side wall, partly cut away; Figure 2 shows a plan view; Figure 3 shows a plan view of a device with the slide omitted; Figure 4 shows, on a larger scale, the mounting of the cutting member; Figure 5 shows a cut through the suction duct, likewise on a larger scale; Figure 6 shows a modified embodiment in a view similar to that of Figure 1.

Referring to the drawings it will be seen that a rectangular housing 1, open at the top, is surrounded by walls on all four sides and in the centre of its base has an opening 2 which is covered by a grating. In the housing 1 there is provided a slide or chute 3 which extends from the upper edge of the front wall and ends just above the opening 2 in the lower part of the housing 1. To the lower end of the slide 3 there is connected a vertical wall 5 which extends to the base of the housing. The angle of inclination of the slide is approximately 40 to 50 to the horizontal.

Guide rails 6 are provided on both sides of the slide. These are adjustable by means of screws 7 which extend through the sidewalls. The guide rails are forked at their lower ends.

At the lower end of the slide there is provided a bow type of saw. This comprises a stay bar or bow 8 and a saw blade 9 which is arranged in a plane extending parallel to that of the slide and which moves to and fro in a longitudinal direction along this plane. The saw blade is arranged in the slot of the forked end of the guide rails 6 which extend downwards and over and beyond the saw blade 9.

The saw blade 9 and the transverse bar of the stay bar or bow 8, parallel to the blade, extend through the longitudinal walls of the housing 1. The stay bar 8 is mounted on resilient lugs 10 which are externally secured to the side walls of the housing 1. Drive is supplied via a motor 11 with an eccentric output member which engages the stay bar 8 in the usual way.

Above the saw blade there is provided a curved grating 12 which is pivotably mounted on a shaft to provide a pendulum action in such a way that when in its rest position it protects the saw blade against being touched inadvertently.

Beneath the lower part of the slide 3, besides the motor 11 there is also a ventilator 13 with its exhaust pipe 14 extending outwards through one of the side walls. The suction pipe 15 of the ventilator 13 penetrates an intermediate wall 16 which seals off a separate chamber 17 beneath the upper part of the slide 3 within the housing 1. This forms the suction chamber for the ventilator 13. Within the suction chamber 17 above the inlet of the suction pipe 15 there is provided a filter mat 18 disposed in a drawer-like withdrawable frame.

Openings 19 connect the suction chamber 17 with the interior of the suction duct 20 (Figure 5). This is formed by a sheet metal profile or section 21 which, with the exception of the front wall 4 from which the slide starts, surrounds the upper edge of the housing 1 like a collar. It has approximately the shape of U lying on one side. The lower arm of the U is closely connected with the associated side wall of the housing 1. The other arm of U is left exposed just a little above the upper edge 22 of the side wall of the housing, exposing a small slot 23. The rigidity is increased by welding stays 24 at various positions.

Behind the opening 2, as seen from the slide 3, a partial chamber 26 is divided off by a transversely extending half-high grating 25.

The front wall 27 opposite the slide is provided with a door 28, as shown in Figure 2. Above the partial chamber 26 a supply roll 29 for the tying-up material is provided at the upper edge of the housing 1.

Figure 6 shows a modified form of the embodi ment. Here, above a sloping sheet metal roof 30, which covers the suction chamber 17 and the adjacent chamber housing the ventilator 13 and the motor 11, there is provided an adjustable slide or chute 31, which is pivotable through a certain angle about an axis 32, as indicated by the double arrow.

The slide can be fixed in any desired angular position by simple arresting means (not shown).

The method of operation of the device according to the invention is as follows: The bag to be opened, which for example may be brought on a forklift truck or a lorry, is manually placed upon the slide 3. Through its own weight it slides downwards and is cut open by the saw blade 9. It then discharges its contents more-or-ess automatically, the contents falling through opening 2 into a mixer or other receiver disposed beneath. Anything remaining in the bag is shaken out by hand.

The opened and emptied bag is initially deposited in the partial chamber 26.

The ventilator 13 is continuously in operation and sucks air from the interior of the housing through the slot 23. This prevents the unavoidable dust raised during cutting and depositing of the bag from reaching the surrounding atmosphere.

The grating 13 is raised from its rest position by the downward sliding bag so that it does not obstruct the bag. The rounded-off shape of the grating also enables the emptied bag to be puiled up without difficulty. After the bag has been removed, the grating once again takes up its rest position and prevents the operator from accidentally touching the running saw blade.

When the collecting chamber 26 is filled with empty bags, the typing-up string, which is pulled from the supply roll 29 at the beginning of the operation and placed in the housing, is used to tie up the bags and the resulting stack is then removed through the door 28.

While certain modifications of the specific embodiment have been described with reference to Figure 6, other modifications may be made, notably the provision of an endless cutter or bandsaw, which preferably has a variable-speed drive, for continuous circulatory motion instead of reciprocatory or toand-fro motion.

Claims (19)

1. A device for cutting open and emptying bags, having a supportforthe bags and a cutting member arranged at the end of the support and a discharge opening beneath the cutting member, wherein the support is formed as a slide surrounded by lateral walls and the cutting member is provided at the lower end of the slide.

2. A device according to Claim 1, wherein the slide is adjustable in slope.

3. A device according to Claim 1 or 2, including lateral guide rails.

4. A device according to Claim 3, wherein at the bottom the guide rails extend above and over the cutting member.

5. A device according to Claim 3 or 4, wherein the guide rails are adjustable in a widthwise direction.

6. A device according to any one of Claims 1 to 5, including an automatic protection device for the cutting member.

7. A device according to any one of Claims 1 to 6, wherein the cutting member comprises a transversely disposed cutter or saw blade.

8. A device according to Claim 7, wherein the cutter or saw blade is held at both sides, under tension, by a stay bar which is movable to and fro by a drive.

9. A device according to Claim 7, wherein the cutter or saw blade is an endless cutter or saw blade which is movable in circuiatory motion by a drive.

10. A device according to Claim 8 or 9, wherein the circulatory speed of the drive is variable.

11. A device according to any one of Claims 1 to 10, including at least one suction opening in the interior of the housing.

12. A device according to Claim 11, wherein the suction opening is constituted by a slot running round the upper edge of the housing.

13. A device according to Claim 12, wherein a surrounding suction duct is connected with the suction chamber of a fan disposed beneath the slide, the suction chamber having a filter.

14. A device according to Claim 13, wherein the fan is also disposed beneath the slide.

15. A device according to Claim 13 or 14, wherein the filter is withdrawable in the manner of a drawer.

16. A device according to any one of the Claims 1 to 15, wherein behind the said discharge opening there is provided a collection chamber for emptied bags.

17. A device according to Claim 16, wherein the front wall, opposite the slide, is provided with a door.

18. A device according to Claim 16 or 17, wherein above the collection chamber there is provided a supply roll fortying-up material.

19. A device for cutting open and emptying bags, substantially as herein described with reference to the accompanying drawings.