Device and method for producing at least one empty open bag

Abstract

Apparatus for manufacturing an open-mouth bag of at least one layer of a flexible bag material, and method of manufacturing a bag by such apparatus. The apparatus includes a shaping device with a shaping box in the contour of the bag shape to be formed, with a top end and a bottom end, a conveying device for transporting the bag material along the shaping box, a closing device for joining the bag material along the shaping box to form a tube, and a closing station for generating a bag bottom, which is disposed beneath the bottom end of the shaping box. A partial vacuum device is configured to generate intermittently, a partial vacuum. When manufacturing a bag, the bag material is draped around the shaping box in the contour of the bag shape to be formed as continuous material and is joined to form a tube by the closing device.

Claims

1. An apparatus for manufacturing at least one open-mouth bag of at least one layer of a substantially flexible bag material, comprising: at least one shaping device with at least one shaping box in a contour of the bag to be formed with a top end and a bottom end; at least one conveying device for transporting the bag material along the shaping box; at least one closing device for joining the bag material along the shaping box to form a tube; at least one closing station for making a bag bottom, disposed beneath the bottom end of the shaping box; and at least one partial vacuum device is provided, which is suitable and configured to generate, at least at the bottom end of the shaping box, at least intermittently, at least a minimal, partial vacuum; wherein the minimal, partial vacuum is at least intermittently generated in the tube of the bag material at least prior to and/or during manufacturing the bag bottom of the next bag; and a transport plunger is displaced for transporting the tube and/or at least intermittently at least a minimal excess pressure is generated in the tube by means of a pressure line, for conveying the tube along the shaping box.

2. The apparatus according to claim 1, that the partial vacuum device comprises at least one partial vacuum line and/or at least one piston and/or at least one Venturi device.

3. The apparatus according to claim 1, characterized in that the shaping box comprises at least one clear flow cross-section from the top end to the bottom end and that the partial vacuum device at the top end is connected with the clear flow cross-section.

4. The apparatus according to claim 3, characterized in that at least the clear flow cross-section and the partial vacuum device do not provide a completely closed system.

5. The apparatus according to claim 1, characterized in that at least one suction intake is disposed at the shaping box.

6. The apparatus according to claim 1, characterized in that the partial vacuum generated by the partial vacuum device is adjustable.

7. The apparatus according claim 1, characterized in that at the bottom end of the shaping box, the at least one transport plunger is at least minimally displaceable in a transporting direction.

8. The apparatus according to claim 7, characterized in that at least one through hole is provided in the at least one transport plunger.

9. The apparatus according to claim 1, characterized in that the at least one pressure line is guided through the shaping box and is configured to generate, at least intermittently, at least a minimal excess pressure in the tube.

10. The apparatus according to claim 1, characterized in that at least one separator is attributed to the closing station.

11. A method of manufacturing at least one open-mouth bag with an apparatus according to claim 1, wherein at least one layer of a substantially flexible bag material is draped around the shaping box in a contour of a bag shape to be formed as continuous material, and is joined by means of the closing device to form a tube, and wherein the closing station manufactures a bag bottom, and at least prior to and/or during manufacturing the bag bottom of a next bag, at least a minimal partial vacuum is at least intermittently generated in the tube of the substantially flexible bag material by means of the partial vacuum device.

12. The method according to claim 11, characterized in that when making the bag bottom of a next bag, a finished bag is cut off by means of a separator.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantages and features of the present invention can be taken from the exemplary embodiment which will be described below with reference to the enclosed figures.

(2) The figures show in:

(3) FIG. 1 a schematic illustration of a perspective total view of a filling apparatus for bulk goods with an upstream apparatus according to the invention for manufacturing a bag;

(4) FIG. 2 a schematic illustration of a perspective view of an exemplary embodiment of an apparatus according to the invention for manufacturing an open-mouth bag;

(5) FIG. 3 a schematic illustration of a front view of an exemplary embodiment of an apparatus according to the invention for manufacturing an open-mouth bag (some components have been omitted for better clarity);

(6) FIG. 4 an enlargement of the marked area in FIG. 3;

(7) FIG. 5 a schematic illustration of a side view of an exemplary embodiment of an apparatus according to the invention for manufacturing an open-mouth bag;

(8) FIG. 6 the view according to FIG. 5, wherein some components have been omitted for better clarity;

(9) FIG. 7 a schematic illustration of a side view of an exemplary embodiment of an apparatus according to the invention for manufacturing an open-mouth bag;

(10) FIG. 8 a schematic illustration of a side view of an exemplary embodiment of an apparatus according to the invention for manufacturing an open-mouth bag;

(11) FIG. 9 a schematic illustration of a side view of an exemplary embodiment of an apparatus according to the invention for manufacturing an open-mouth bag; and

(12) FIG. 10 a schematic view from below of a transport plunger in a shaping box.

DETAILED DESCRIPTION

(13) FIG. 1 shows a perspective total view of an apparatus 200 for filling bulk goods and fluids into flexible open-top, open-mouth bags 100. The bags 100 processed in the apparatus 200 illustrated in FIG. 1 consist of a flexible bag material 101, presently of a plastic material or a film.

(14) In the exemplary embodiment shown the apparatus 200 comprises an apparatus 1 according to the invention for manufacturing open-mouth bags 100, a transfer device 250, a filling carousel 201, and a compaction station, wherein the compaction station is not illustrated in the Figures.

(15) The apparatus 1 according to the invention for manufacturing bags 100 provides bags which, in the exemplary embodiment shown, drop or glide into a transport box 251 of the transfer device 250. Then the transport box 251 pivots and allows the open-mouth bag 100 to drop down into the stock container 202 from above a stock container 202. In the stock container 202 the bag travels on the filling carousel 201 while being filled.

(16) For manufacturing bags 100, bag material 101 is guided from a supply 20 over a shaping shoulder 22 around a shaping box 3, so that the bag material 101 sheet shows at least a minimal overlap. A closing device 7 forms a tube 102 from the bag material 101 draped around the shaping box 3, in which tube the closing station 8 then forms a bag bottom 103.

(17) An open-mouth bag 100 must have a predetermined shape or contour so as to smoothly glide or drop both into the transport box 251 and the stock container 202. This is ensured by means of the apparatus according to the invention for manufacturing open-mouth bags. Moreover it is ensured that the filled bag retains its desired shape even in the case of subsequent compaction if any, or even extreme recompaction.

(18) The FIGS. 2 to 6 schematically show various views of an exemplary embodiment of an apparatus 1 according to the invention for manufacturing empty bags 100.

(19) The apparatus 1 comprises in the exemplary embodiment shown, other than a supply 20 for bag material 101, a diverter system 21 comprising several rollers, over which the layer of bag material 101 is fed to the shaping box 3 across a shaping shoulder 22, which is not shown in detail in the FIGS. 2 through 6. In the exemplary embodiment shown, the shaping shoulder 22 and the shaping box 3 form the shaping device 2.

(20) The shaping box 3 shows the contour of the open-mouth bag 100 to be manufactured, wherein the layer or layers of bag material 101 are suitably fed to, or guided around, the shaping box 3 over the shaping shoulder 22, so that the bag material can be joined to form a tube 102 by means of a closing device 7, in the contour of the bag 100 to be formed.

(21) The bag material 101 draped around the shaping box 3 is transported along the shaping box 3 by means of a conveying device 6, which in the exemplary embodiment shown comprises a pair of belt drives 23. The belt drives 23 urge the bag material 101 against the shaping box 3, thus transporting the bag material 101 or the tube 102 along the transporting direction 16 over the shaping box 3.

(22) The shaping box 3 shows a top end 4 and a bottom end 5, with a closing station 8 provided beneath the bottom end 5, which, by making a bag bottom 103, manufactures from the tube 102 of bag material 101, a bag 100 or a bag blank, which is cut off of the tube 102 by means of a separator 19.

(23) According to the invention a partial vacuum device 9 is provided, which generates at least a partial vacuum at the bottom end 5 of the shaping box 3.

(24) FIG. 7 schematically illustrates an exemplary embodiment of an apparatus 1 according to the invention, for better clarity illustrating only the shaping box 3, the closing station 8, and the separator 19.

(25) It can be seen that bag material 101 or a previously formed tube 102 of bag material 101 is transported along the shaping box 3, which shows the contour of the intended open-mouth bag 100.

(26) FIG. 7 schematically illustrates what happens when the closing station 8 closes for forming a bag bottom 103. Since the tube 102 with the bag bottom 103 of the previously manufactured bag 100 is still appended beneath the shaping box 3, any air present in the tube 102 is also urged into the section of the tube 102 showing the bag bottom 103 which is positioned in the bottom in the transporting direction 16, as the closing station 8 closes for forming the bag bottom 103 of the following bag 100.

(27) This causes the section to inflate and the bag walls 104 to bulge outwardly. Although the excess pressure now prevailing in the bag 100 escapes as soon as the separator 19, in this case a fly cutter 24, has cut off the open-mouth bag 100, which is then open on top, from the remainder of the tube 102. However, the bag walls 104 do not reset completely or satisfactorily. The drawback thereof is that the bag cannot glide as readily into a transport box 251 disposed beneath, nor can it glide into the stock container 202 later.

(28) FIG. 8 illustrates that in the exemplary embodiment shown, a partial vacuum is generated at the bottom end 5 of the shaping box 3 through a clear flow cross-section 13 inside of the shaping box 3, via a suction intake 14. The suction intake 14 is provided at the top end 4 of the shaping box. The top end 4 is not necessarily understood to mean the topmost section of the shaping box 3 but any section of the shaping box 3 which is not yet entirely enclosed in the bag material 101, so as to provide free access to the shaping box 3. Thus, optionally from above as well.

(29) Presently, the partial vacuum is provided by a partial vacuum line 10 connected with the suction intake 14. Depending on the configuration, the partial vacuum device 9 may also comprise, for example a piston 11 and/or a Venturi device 12.

(30) As indicated in FIG. 8, a slight partial vacuum is generated by means of the partial vacuum device 8 in the tube section of the previously formed bag, so that the bag wall 104 is slightly hollowed inwardly.

(31) Now when the closing station 8 closes, air is again pressed out of the tube 102, also into the tube section beneath the closing station 8, so that in the shown example, the bag wall 104 once again bulges outwardly so as to form an open-mouth, empty bag 100 showing the desired contour, which is predetermined by the shaping box 3 and is suitable for further processing.

(32) Moreover, by generating a slight partial vacuum, at least while the bag bottom 103 of the next bag 100 is being made, or while the closing station 8 is closing, it is achieved that the bag material 101 or the stacked layers of bag material 101 are not displaced during the making of the bag bottom 103, so as to generate a properly shaped bag bottom 103 or closing seam 105, for example in the form of a weld seam and/or glued seam.

(33) FIG. 9 indicates schematically that the bottom end 5 of the shaping box 3 may be provided with a transport plunger 15 which can move in the transporting direction 16 and counter to the transporting direction 16. The transport plunger 15 in the shown exemplary embodiment is conical, so that at least part of the transport plunger 15 can be accommodated in the shaping box 3. Another section of the transport plunger 15 continues the outer contour of the shaping box 3. The outer periphery of the transport plunger 15 is preferably minimally smaller than the outer periphery of the shaping box, so that the film can readily glide across and is not pulled back during the reverse movement of the transport plunger 15.

(34) The movement of the transport plunger 15 in the transporting direction 16 results in continued further conveying of the tube 102 formed around the shaping box 3, even if in this area, the conveying device 6 has lost contact with the tube 102, thus pushing the bag material 101. The transport plunger 15 eases the gliding off or the releasing or the setting in motion of the tube 102 off of the shaping box 3.

(35) Moreover, FIG. 9 schematically illustrates that a pressure line 18 may be in functional connection with the bottom end 5 of the shaping box through the shaping box 3 or in another suitable way. Thus, the pressure line may cause generation of excess pressure in the last tube section so as to assist in transporting the bag 100 or the tube 102 prior to cutting off the bag 100.

(36) FIG. 10 schematically shows a view from below of a transport plunger 15 in a shaping box 3. It can be seen that the transport plunger 15 fills the entire cross section of the shaping box 3, so as to prohibit the generation of a partial vacuum at the bottom end 5 of the shaping box 3 passing through the shaping box 3.

(37) Therefore, several through holes 17 are provided in the transport plunger 15 in the exemplary embodiment shown, through which a partial vacuum applied through the shaping box 3 may also act at the bottom end 5 of the shaping box 3 through the transport plunger 15, or air can flow back in while the tube 102 is conveyed further.

(38) Moreover, FIG. 10 illustrates that the pressure line 18 may also show its own through hole 17, or it may be disposed in another through hole 17, so that even a temporary excess pressure can be applied in the tube 102 beneath the shaping box 3 passing through the transport plunger.

(39) While a particular embodiment of the present apparatus and method of manufacturing at least one empty, open-mouth bag has been described herein, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.

LIST OF REFERENCE NUMERALS

(40) 1 apparatus 2 shaping device goods 3 shaping box 4 top end 5 bottom end 6 conveying device 7 closing device 8 closing station 9 partial vacuum device 10 partial vacuum line 11 piston 12 Venturi device 13 clear flow cross-section 14 suction intake 15 transport plunger 16 transporting direction 17 through hole 18 pressure line 19 separator 20 supply 21 diverter system 22 shaping shoulder 23 belt drive 24 fly cutter 100 open-mouth bag 101 bag material 102 tube 103 bag bottom 104 bag wall 105 closing seam (weld seam, glued seam) 200 filling apparatus for bulk 201 filling carousel 202 stock container 250 transfer device 251 transport box