Title of Invention

EMPTYING DEVICE FOR BULK BAGS

Abstract

The invention relates to an emptying device for bulk bags having an inner and outer sack in which disturbances during emptying and contact with the bulk material are avoide The device comprises a holding device (3) for the bulk bag, a double tube device arranged centrally beneath the holding device and having an inner tube (20), an outer tube (7) arranged around the inner tube with an outlet (8) fitted to its lower edge, and a closing ring (9) which can be raised and lowered for closing the upper end of the annular gap formed by the two tubes. According to a preferred embodiment, the device additionally comprises at least one gripping device (21) for securing the sack outlet of the inner sack, which gripping device can be moved up and down within the inner tube and can be pulled downwards by means of a pulling device (11) operable from outside the double tube device.

Full Text

- 1A - This invention relates to an emptying device for bulk bags. Description The invention relates to an emptying device for bulk bags having an inner and outer sack, which is particularly suitable for the dust-free emptying of bulk bags filled with moisture-sensitive, toxic or corrosive fluid bulk materials. The invention also relates to a method for emptying bulk bags using the emptying device according to the invention. It is known to market fluid bulk materials in large sack-like containers referred to in the following as bulk bags. Bulk bags for receiving corrosive, toxic and/or otherwise sensitive, possibly hygroscopic, bulk materials usually comprise a sealing-tight inner sack, also called an inliner, and a mechanically stable outer sack. The inner sack is usually made of a sufficiently thick film of plastics material or a compound film, for example a plastics material film coated with aluminium. The outer sack is generally made of a natural or synthetic textile material, often a ribbon woven. In their upper region, bulk bags with an inner and outer sack usually comprise a closable filling aperture, which is also used for ventilation during emptying, and carrying loops which allow for handling using lifting tools. Arranged at the base of the bulk bag are the outlet necks, which are fitted within - one another and are closed by means of a lower and an upper sack tie, which generally enclose both sacks. In addition, the outlet neck of the inner sack is welded in a sealing-tight manner, usually beneath the lower sack tie. The tied and/or welded outlet neck of the inner sack can be folded in a suitable manner and arranged within the outlet neck of the outer sack. 960062 OC 2 In order to empty the bulk bags, the latter are brought over the container which is to be filled by means of the handling tools and are emptied after opening the sack ties. Dust-free emptying is not possible in this manner. For dust-free emptying of bulk bags, various emptying devices have become known. EP-A 0 637 552 teaches a metering pallet for bulk bags, a container which is open at the top being arranged beneath the opening of a receiving plate for the bulk bag, the side wall of the container comprising a device for opening and closing the container and the underside of the container being connected to a metering device. After placing the bulk bag on top of the receiving plate with the outlet neck reaching into the container, the ties can be opened through the side door in the container. If the inner sack of the bulk bag is made of a material with low flexibility, such as an aluminium-lined compound film, it is not possible to rule out disturbances in the outflow as a result of bridge formations. This is particularly a great disadvantage in cases where access to the emptying device through the side door is not possible on account of the toxic or corrosive character of the product. A similar device is taught in GB-A 2 250 016: Apart from a receiving dish for receiving the outlet neck and the lower part of the bulk bag and a door in this dish for handling the sack ties, this emptying device also comprises a squeezing device for reducing or completely interrupting the bulk material flow and for retying the sack. This device is also unsuitable for the problem-free emptying of bulk bags, in particular those with an inner sack of low flexibility- and/or a welded inner sack, since disturbances during emptying as a result of blockages in the outflow cannot always be avoided, but contact of the contents with the skin is not permissible for hygiene reasons. 960062 OC 3 It is therefore the object of the invention to provide an emptying device for bulk bags having an inner and outer sack, by means of which said bags can be reliably emptied in a problem-free manner, without having to come into contact with the contents. According to a further object, the emptying device is also to be suitable for emptying bulk bags having an inner sack with low flexibility, as are used in the case of dangerous substances. This object is achieved by the emptying device according to the invention. An emptying device was therefore invented for bulk bags having an inner and outer sack, comprising a holding device (3) for the bulk bag and a container-like device, which is open at the top and is arranged substantially centrally beneath the holding device, characterised in that the container-like device is constructed as a double tube device, comprising an inner tube (20), an outer tube (7) arranged around the inner tube with an outlet (8) fitted to its lower edge, and a closing ring (9) which can be raised and lowered in order to close the upper end of the annular gap formed by the two tubes. The subclaims of the emptying device relate to preferred embodiments of the invention. The device according to the invention is suitable for dust-free and safe emptying of bulk bags filled with dangerous substances. The device is based on a double tube device, whose preferably funnel-shaped outlet can be connected to the container to be filled via a fitted flexible socket. The emptying device comprises a holding device for the bulk bag, which is expediently constructed as a receiving dish mounted on a frame and comprising a sufficiently wide opening arranged in the centre through which the sack outlet of the bulk bag can be guided. Arranged substantially centrally beneath the receiving dish is the double tube device. A preferred device also comprises a lifting/lowering device acting upon the double tube device, 960062 OC 4 so that the distance between the receiving dish and the double tube device can be increased or reduced. By means of the raisable and lowerable closing ring of the double tube device, the upper end of the annular gap formed by the two tubes is closed in a sealing-tight manner. In order to empty the bulk bag, the latter is placed upon the receiving dish in such a manner that the sack outlet extends through the opening. After opening the lower sack tie, the sack outlet of the outlet necks of the inner and outer sacks fitted within one another is guided through the closing ring; the outlet neck of the inner sack is inserted after appropriate folding or crumpling into the inner tube and the outlet neck of the outer sack is inserted into the annular gap formed by the two tubes. The closing ring is then lowered in order to securely fix the outer sack and to seal the device relative to the environment. After opening the upper sack tie, the bulk bag begins to empty. In addition, it is generally expedient to lower the double tube device in order to stretch the outlet necks fitted within one another between the double tube device and the outlet dish. A preferred embodiment of the emptying device, as is particularly suitable for emptying bulk bags having an inner sack with a low degree of flexibility since a blocking of the outlet is prevented by additional stretching of the outlet neck of the inner sack, is characterised in that it comprises at least one gripping device (21), which can be raised and lowered within the inner tube, for securing the sack outlet of the inner sack, it being possible to pull the gripping device downwards by means of a pulling device (11) operable from outside the double tube device. The invention and preferred embodiments as well as the function thereof will be explained in further detail with the aid of Figures 1 to 3. '960062 OC 5 In the accompanying drawings: Figure 1 is a schematic side view of a preferred emptying device according to the invention, Figure 2 is an enlarged sectional detail according to the area II in Figure 1, and Figure 3 is a view similar to Figure 2 in a different operating position. All the drawings relate to a preferred embodiment, and in addition to the double tube device according to the invention also illustrate a gripping and pulling device. Figure 1 is a schematic side view of a device for emptying packaging known per se in the form of a large sack-like container, referred to in the following as a bulk bag. The bulk bag (1) comprises an inner sack accommodating the pourable substance with an outer sack arranged around the inner sack (not shown in Figure 1, nos. 18 and 17 respectively in Figure 2). The outlet neck (13) of the bulk bag, which comprises the outlet necks of the inner sack and the outer sack fitted within one another, is sealed and secured by a lower sack tie (14) and an upper sack tie (15). A portion of the outlet neck of the inner sack, which may be optionally additionally sealed by welding, is located in a suitably folded manner within or at the upper end of the outlet neck of the outer sack. By means of carrying loops (2) secured to the bulk bag, the bulk bag can be brought by means of a crane or a forklift truck, which can itself already fulfil the function of a holding device for the bulk bag, into a substantially central position above the double tube device. The preferred embodiment of the holding device for the bulk bag shown in Figure 1 is a receiving device mounted on a support frame (4), more particularly a receiving dish (3) with a centrally disposed opening, through which the sack outlet neck (13) is guided. The double tube device is arranged centrally beneath the opening of the receiving device, namely at such a distance that the outlet neck of the bulk bag extends into the double tube device. The 960062 OC 6 emptying device expediently comprises a lifting/lowering device (5), so that the double tube device secured thereto by means of holding elements (6) can be raised and lowered. The lifting/lowering device (5) only schematically illustrated in Figure 1 can, as shown, act upon the support frame (4) or a holding element secured separately to the receiving dish. According to a further embodiment, it is possible to equip the receiving device for the bulk bag with a lifting/lowering device instead of the double tube device; however, it is preferable for the double tube device to be equipped with the lifting/lowering device. The lifting/lowering device can be constructed in any desired manner and can be mechanically, pneumatically or electrically actuated. The lifting/lowering device is especially preferably based on a combination of a spring and a manually actuated lifting device, it being possible to lower the double tube device by compressing the spring by means of the lifting device. The double tube device usually rests upon two oppositely disposed holding elements, each on a lifting/lowering device. Of the double tube device itself, in Figure 1 shows the outer tube (7), the outlet (8) which is fitted to the lower edge and is funnel-shaped in this case, a pipe socket (12) which is fitted to the outlet funnel and through which the bulk material is supplied directly or via a metering device to the container to be filled. Further component parts of the double tube device are the closing ring (9), which can be lowered onto the double tube and raised again by means of one or more lifting/lowering devices, constructed as closing braces (10) in Figure 1, and one or more gripping devices (21), which are an essential feature of the invention, with associated pulling devices (11). In Figure 1, the emptying device rests upon a receiving platform- (16) . In the enlarged detail drawing of Figure 2, details of the double tube device and the gripping and pulling device which is particularly expedient for emptying bulk bags 960062 OC 7 having an inner sack with low flexibility can be recognised. The inner tube (20) is disposed centrally within the outer tube (7). Fitted to the bottom edge of the outer tube is an outlet funnel (8) and an outlet socket (12) is in turn fitted to the outlet funnel. The inner tube is secured by means of one or more securing means (35) to the lower part of the outer tube or the upper part of the adjoining outlet; the annular gap formed between the inner and outer tubes should remain essentially free in order to receive the end portion of the sack outlet of the outer sack. The holding elements (6) acting upon the outer tube and leading to the lifting/lowering device - not illustrated in Figure 2 - for the double tube is schematically illustrated. The closing ring (9), which is shown in its open position, is provided on its underside with a sealing ring (19). The lifting/lowering device (10) for the closing ring - Figure 2 shows two devices of this type arranged opposite one another - is constructed in Figure 2 in the form of closing braces: The closing lever (31) acts at one end upon a lever mount with a hinge joint (33), and at the other end via a hinge joint upon a closing bracket (32), which is in turn pivotably secured via a hinge joint to the bracket mount (34) fixed to the closing ring. Two closing braces are illustrated in Figures 2 and 3 respectively, although it can be expedient to arrange three or four closing braces symmetrically around the outer tube. The width of the closing ring is dimensioned in such a manner that the annular gap formed between the inner and outer tubes can be completely covered. In the preferred embodiment according to Figure 2, three gripping devices (21) constructed as clamps are shown. In the preferred embodiment of Figures 2 and 3, the pulling device (11) comprises a lower cable line (22) acting upon the gripping device, an upper cable line (23) also acting upon the gripping device, guide elements (26) for deflecting the lower cable line under the lower edge of the inner tube, guide elements (27) for guiding the upper cable line through the wall of the inner tube, a sleeve (24 and 25) in 960062 OC 8 each case for guiding the lower and upper cable lines through the wall of the outer tube, a seal (28 and 29) in each case for the lower and upper cable lines and a handle (30) for each cable line. The cable line sleeves {24 and 25) are arranged in the lower part of the outer tube, so that the upper cable line extending in the annular gap does not impede the reception of the end portion of the sack neck of the outer sack. In the operative position illustrated in Figure 2, the sack outlet neck with the upper sack tie (15) is disposed within the opening of the opened closing ring. Whilst the end portion of the outlet neck of the inner sack (18) is- shown ready for securing by the gripping devices, the end portion of the outlet neck of the outer sack is shown still outside the closing ring for the sake of clarity in the drawing. Figure 3 illustrates the "emptying" operating position, the end portion of the outlet neck of the outer sack lying in the annular gap and being secured by means of the lowered closing plate. The end portion of the outlet neck of the inner sack, whose edge is grasped by the gripping devices, is disposed in a stretched position within the inner tube. The sack is expediently secured by the gripping devices in the region of seams or reinforcements. The stretching of the outlet neck is effected on the one hand by pulling down the gripping devices and on the other hand by lowering the entire double tube device. In Figure 3, the distance between the double tube device and the receiving dish is increased by the lowering as compared to the distance in Figure 2. The gripping device (21) and pulling device (11) illustrated in Figures 2 and 3 and comprising components (22 to 30) constitute a highly effective design which can be simply but reliably handled in spite of the use of extremely simple technical means. Of course, both the gripping device and the pulling device can be designed 960062 OC 9 differently, although this involves an increase in technical outlay and therefore in the cost of the emptying device, without any significant additional advantages being gained. The emptying of a bulk bag with an inner sack of low flexibility using the emptying device according to the invention comprises the following steps: 1. Securing of the bulk bag by means of a holding device. In principle, the function of the holding device can already be fulfilled by suspension from a crane or forklift truck. However, it is substantially more expedient to place the bulk bag on a holding device with an opening arranged in the centre, the outlet neck being guided through the opening. 2. Opening of the lower sack tie and release of the outlet of the inner sack. Guidance of the outlet necks of the inner and outer sacks fitted within one another through the opened closing ring. Severance of a welding seam in cases where the inner sack is welded. 3. Fixing of the gripping devices to the edge of the outlet of the inner sack and stretching of the outlet neck by actuating the pulling device. Introduction of the outlet neck of the outer sack into the annular gap and fixing of the outlet neck of the outer sack by lowering the closing ring. 4. Opening of the upper sack tie, so that emptying begins and lowering of the double tube device. If necessary, the pulling device can be re-actuated in order to keep the outlet neck of the inner sack taut. The device according to the invention and the emptying method using this device are characterised by a high degree of simplicity and safe handling. The emptying of the bulk 960062 OC 10 bag is effected in an entirely dust-free manner and the operator does not come into contact with the contents. By using the gripping and pulling device, it is also possible to reliably stretch outlet necks of inner sacks having low flexibility and to avoid disturbances during the emptying of the bulk bag. 960062 OC 11 Reference Numerals 1 bulk bag 2 carrying loop 3 holding device (receiving dish) 4 support frame 5 lifting/lowering device 6 holding elements for double tube 7 outer tube 8 outlet (outlet funnel) 9 closing ring 10 closing brace 11 pulling device 12 pipe socket 13 sack outlet neck 14 lower sack tie 15 upper sack tie 16 receiving platform 17 outer sack 18 inner sack 19 sealing ring 20 inner tube 21 gripping device (clamp) 22 lower cable line 23 upper cable line 24 lower cable line sleeve 25 upper cable line sleeve 2 6 guide element for deflecting the lower cable line 27 guide element for deflecting the upper cable line 28 seal for lower cable line sleeve 29 seal for upper cable line sleeve 30 handle 31 closing lever 32 closing bracket 33 lever mount with hinge joint 34 bracket mount with hinge joint 35 securing means between inner and outer tube 27 12 1. Emptying device for bulk bags having an inner and outer sack, comprising a holding device (3) for the bulk bag and a container-like device open at the top which is arranged substantially centrally beneath the holding device, characterised in that the container-like device is constructed as a double tube device, comprising an inner tube (20), an outer tube (7) arranged around the inner tube and having an outlet (8) fitted to its lower edge, and a raisable and lowerable closing device (9) for closing the upper end of the annular gap formed by the two tubes. 2. Emptying device as claimed in claim 1, characterised in that it comprises at least one gripping device (21) for securing the sack outlet of the inner sack, which gripping device can be raised and lowered within the inner tube and can be pulled downwards by means of a pulling device (11) operable from outside the double tube device. 3. Emptying device as claimed in claim 1 or 2, characterised in that the holding device for the bulk bag is constructed as receiving device (3) mounted on a support frame (4), more particularly a receiving dish with a centrally arranged opening through which the sack outlet neck (13) is guided, and the double tube device is mounted on the receiving device or support frame so as to be raisable and lowerable by means of one or more lifting/lowering devices (5) . 4. Emptying device as claimed in one or more of claims 1 to 3, characterised in that the closing ring (9) can be lowered in order to close the annular gap by means of one or more lever devices, more particularly closing braces, acting upon the outer tube and closing ring. 5. Emptying device as claimed in one or more of claims 1 to 4, characterised in that the outlet (8) is funnel-shaped 960062 OC 13 and preferably additionally comprises a fitted outlet socket (12). 6. Emptying device as claimed in one or more of claims 2 to 5, characterised in that it comprises two to four gripping devices, more particularly clamps, and the pulling devices (11) associated with the gripping devices each comprise an upper and lower cable line (23 and 22) acting upon the gripping device, the cable lines being guided out of the double tube device by means of guide elements in such a manner that the gripping device is moved downwards by pulling the Tower cable line and upwards by pulling the upper cable line. 7. Emptying device as claimed in claim 6, characterised in that the upper cable line is guided through the wall of the inner tube in the upper section of the inner tube and the lower cable line is guided through said wall or beneath the lower edge thereof in the lower section, and both cable lines are guided out of the double tube device in the lower section of the outer tube or at the fitted outlet. 8. Method for emptying a bulk bag having an inner and outer sack, characterised in that an emptying device according to one of claims 2 to 7 is used, and the emptying comprises the following steps: securing of the bulk bag by means of a holding device; opening of the lower sack tie and release of the outlet of the inner sack; guidance of the outlet necks fitted within one another through the central opening of the closing ring and removal of any welding which may be present on the inner sack; fixing of the gripping device(s) to the edge of the outlet of the inner sack; introduction of the outlet neck of the outer sack into the annular gap between the inner and outer tubes; lowering of the closing ring in order to secure the outlet edge of the outer sack; stretching of the outlet edge of the inner sack by pulling down the gripping device; opening of the upper sack tie; 960062 OC 14 lowering of the double tube device in order to stretch the outlet neck of the inner and outer sack. Dated this 3rd day of OCTOBER 1997. The invention relates to an emptying device for bulk bags having an inner and outer sack in which disturbances during emptying and contact with the bulk material are avoide The device comprises a holding device (3) for the bulk bag, a double tube device arranged centrally beneath the holding device and having an inner tube (20), an outer tube (7) arranged around the inner tube with an outlet (8) fitted to its lower edge, and a closing ring (9) which can be raised and lowered for closing the upper end of the annular gap formed by the two tubes. According to a preferred embodiment, the device additionally comprises at least one gripping device (21) for securing the sack outlet of the inner sack, which gripping device can be moved up and down within the inner tube and can be pulled downwards by means of a pulling device (11) operable from outside the double tube device.

Documents:

01861-cal-1997 abstract.pdf

01861-cal-1997 claims.pdf

01861-cal-1997 correspondence.pdf

01861-cal-1997 description(complete).pdf

01861-cal-1997 drawings.pdf

01861-cal-1997 form-1.pdf

01861-cal-1997 form-2.pdf

01861-cal-1997 form-3.pdf

01861-cal-1997 form-5.pdf

01861-cal-1997 form-6.pdf

01861-cal-1997 form-gpa.pdf

01861-cal-1997 priority document.pdf

1861-cal-1997-granted-acceptance publication.pdf

1861-cal-1997-granted-claims.pdf

1861-cal-1997-granted-correspondence.pdf

1861-cal-1997-granted-description (complete).pdf

1861-cal-1997-granted-drawings.pdf

1861-cal-1997-granted-examination report.pdf

1861-cal-1997-granted-form 1.pdf

1861-cal-1997-granted-form 2.pdf

1861-cal-1997-granted-form 3.pdf

1861-cal-1997-granted-form 5.pdf

1861-cal-1997-granted-gpa.pdf

1861-cal-1997-granted-letter patent.pdf

1861-cal-1997-granted-reply to examination report.pdf

1861-cal-1997-granted-specification.pdf