EP0016691A1 - Apparatus for automatically filling sacks at the outlet nozzle of a filling funnel - Google Patents

Abstract

An apparatus for the automatic filling of bags at a discharge spout of a filling hopper wherein empty bags are stored in a bag magazine in a horizontal position, the apparatus including an attachment unit hub, a frame pivotably mounted on the hub, a suction device mounted on the frame for individually removing each bag from the bag magazine and for swinging the removed bag into an essentially vertical hanging position and including a drum having suction mechanism, a spreading mechanism mounted on the frame for opening a respective bag mouth, and a holding device for holding each bag mouth tightly against the discharge spout, wherein the drum is mounted on the frame for horizontal movement and for rotation about an axis parallel to the surface of the stored bags and for movement parallel to the longitudinal axis of the stored bags upon pivoting of the frame about the attachment unit hub, such that the drum is lowered towards the stored bags so that the suction mechanism seizes the respective topmost bag of the bag magazine near the mouth of the individual bag.

Description

The invention relates to a device for automatically filling sacks at the outlet of a hopper, the empty sacks being stacked in a sack magazine in a horizontal position, with a suction device for individually removing the sacks from the sack magazine and for pivoting the respective sack into an im essentially vertical hanging position, with a spreading device for widening the respective sack into its mouth area and with a holding device for clamping the sack mouth at the outlet nozzle.

Fully automatic devices for filling bags, e.g. B. made of paper, plastic and the like, have been known for some time. In a known device (GB-PS 1 224 317), an empty sack is removed from the stack by means of a first pneumatic cylinder via a suction cap, pulled apart at the filling opening by means of a second cylinder, and pivoted via a hinge axis before a filling device placed. The two sides of the sack must be held near the sack opening by two pairs of clamps, each of which clamps the area of the sack side in question close to the edge between them. The known device is complex and complicated and carries out a large number of individual work steps, with an additional link between the individual work steps being given: the starting position of the device can only be taken up again after all the individual steps have been completed.

In another known bag filling device (DE-AS 23 61 037) of the type mentioned at the outset, the suction elements used for bag separation are fastened to arms with an axis which is fixed to the frame and which is arranged parallel to one of the two bag sides. The gripped sack is first transferred from its horizontal stacking position into a substantially vertical position, then it is gripped by suction elements that are arranged on pivotable arms in its area near the mouth, then transferred to a position pivoted by approximately 90 ° (vertical hanging position) and thereby at the same time slipped over the discharge nozzle of the hopper. In this way it can be achieved that the time sequence of the filling process is determined by the duration of the slowest of the individual steps and that it is no longer possible to reach the starting position only after all individual steps have been completed. However, this known device still requires the use of a plurality of pivotable individual elements, the uppermost sack picked up from the sack stack having to be transferred from the receiving device to another pivoting device before it can reach the outlet nozzle of the filling funnel. This transfer of the picked-up sack from the receiving device to another device for putting it on the outlet butting the hopper in turn offers the possibility of malfunctions.

Proceeding from this, the object of the invention is to improve such a known device in such a way that further increased operational reliability is achieved, the number of pivoting elements is reduced and, at the same time, the change in position caused by the guide movements of the gripped bag is kept as small as possible until it is slipped onto the outlet nozzle . According to the invention, this is achieved in a device of the type mentioned at the outset in that the suction device for the individual removal of the sacks from the sack magazine is designed as a drum provided with adhesives, which can be displaced horizontally in a frame by a parallel to the surface of the sacks stored in the sack magazine and perpendicular to the longitudinal axis of the axis is rotatably mounted and can be lowered onto the sacks in such a way that the sack of the sack magazine lying on top is gripped by the adhesive means only in the vicinity of the sack opening. The device according to the invention enables a particularly safe, fully automatic operation in that the sack is held here only by one device, namely the drum, from its position in the sack magazine to being slipped over the outlet nozzle of the filling funnel. The sack is transported in a very short way from its position in the top of the sack magazine to its slip-on position at the outlet nozzle of the filling funnel, without it being necessary to switch on several swiveling movements of the sack which are perpendicular to one another. The entirety of all the steps taking place can essentially be carried out in the context of a slight angular rotation of a drum (approximately a quarter turn) and smaller horizontal and vertical Shifting movements take place without the sack having to be transferred from one device to one or more others on its way from the sack magazine to the outlet nozzle. The simple movement ensures not only a particularly rapid time _l cozy flow, but also allows a remarkably simple control option:

In a device according to the invention, the drum is preferably rotated after it has been lowered onto the sacks and after the subsequent activation of the adhesives to raise the end of the sack on the opening side of the sack. During or even after this twisting movement, which is preferably carried out by a range of 90 °, the drum is raised in order to separate the uppermost sack from the sack magazine particularly effectively and quickly from the sacks below it. Pneumatic suction cups or the like are preferably used as the adhesive on the outside of the drum. used. The function of the drum used is as follows: the drum ("adhesive drum") is lowered onto the sack in such a way that the adhesives attached to the drum can grip the sack located at the top near the sack opening. When lowering, the drum is lightly pressed onto the stack of sacks and then the suction cups are activated, ie, placed under negative pressure in such a way that they remove the uppermost sack of the stack with a relatively strong suction force. It is recommended that the adhesives are arranged on the outside of the drum distributed over a width corresponding to the width of the sacks to be picked up, at least two to three suction cups being brought into action. Then the drum with the suction cups attached to it and the detected bag opening area is mechanically subjected to a rolling movement such that the open bag end is one-sided is raised. It has been shown that with such a rolling movement, especially if suction cups are attached over the entire width of the sack, the entire gripped sack is curved upwards on this side and thus detaches from the next lower one. If, at the same time or afterwards, the drum is slightly lifted and thus another, slight lift of the sack takes place, air can very easily enter between the two top sacks, but in particular adhesive effects due to moisture or the like can be eliminated very effectively. After the rolling movement or immediately leading from the rolling movement, the drum brings the sack into a vertical position below the sack spout. Depending on the length of the bag, it is sufficient, for. B. only bring the upper third of the sack into the vertical position. According to this, a clamping jaw cooperating with the drum for widening the opening of the gripped sack is preferably brought up to the sack hanging on the suction cups of the drum in such a way that the drum and clamping jaw preferably press the opening end of the sack together with slight pressure. The same or similar adhesives as on the drum are provided on the clamping jaw. In order to achieve completely trouble-free and stop-free, merging motion sequences, it has proven to be surprisingly effective if the adhesives are attached to flexible leaf springs both on the drum and on the clamping jaw, the latter preferably being connected to mechanical actuating elements in such a way that they can be brought into a bulbous shape in such a way that the adhesive which is effective from the clamping jaw on one side and from the drum on the other side in the mouth region of the gripped sack is brought into such a position that the sack is pulled apart at its opening and the opening area of the gripped sack in the is essentially brought into an oval expanded shape. Thus, the opening of the sack takes place on the upper edge through a deformation of the leaf springs of both the clamping jaws, as well as the drum and the suction cups attached to them (spread apart). By a still short vertical movement, the sack opened in this way can then be pulled onto the sack nozzle, which is also usually made in an oval shape, in such a way that '. B. the upper edge of the bag is 5 to 10 cm higher than the lower edge of the filler neck.

In an advantageous embodiment of the device according to the invention, the drum and clamping jaw are brought into an upper lifting position after the sack opening has been widened, the opened sack end region being guided over the outlet connection. It is advantageous if the holding device for clamping the bag mouth on the outlet nozzle can only be actuated when the drum and clamping jaw have reached their upper lifting position.

The overall flow of the device turns out to be very fluid, i. H. without the occurrence of large jerking movements, which is particularly clearly the case when the drum as well as the clamping jaw are driven by pneumatic actuation means, in particular by pneumatic cylinders.

In order to ensure a uniform opening of a sack during the opening movement, it is advantageous if there is a rigid connection between the actuating means of the drum and the clamping jaw, i.e. if the actuating means for the drum and for the clamping jaw are in a fixed association with one another (e.g. on the frame ) are attached. It is also important that the two leaf springs simultaneously one during opening perform the same sequence of movements.

In an advantageous embodiment of the device according to the invention, a carousel which can be rotated about a vertical axis by means of a motor and has a plurality of outlet nozzles is provided which, after a bag has been attached to an outlet nozzle which is in the loading position (filling position), can be rotated such that a new outlet nozzle reaches the filling position. The carousel preferably has four, five or six outlet connections and is advantageously brought into the respective loading or filling position with a pole-changing motor. It is advantageous if the motor of the carousel can be switched to a fast and a slow speed, again, preferably with a brake, and one of its phases can be connected to a resistor (when starting).

A further improvement of the device according to the invention with regard to the automatic sequence is achieved in that an optical control element (detector) is attached to the adhesive drum, which can determine the presence of a sack and possibly a sack label and report it to a central control and command unit.

The device according to the invention can advantageously be switched so that it simultaneously prepares (detects) a new sack while the carousel brings the nozzle to be hung into the ready position.

• Fig. 1 eine Gesamtansicht der erfindungsgemäßen Vorrichtung;
• Fig. 2a bis 2e eine Darstellung der Hauptbewegungsabläufe bei der Sackaufnahme;
• _Fig. 3 eine prinzipiell dargestellte Draufsicht auf eine erfindungsgemäße Vorrichtung in einer Position gemäß Fig. 2e;
• _Fig. 4 eine prinzipielle Darstellung der Draufsicht einer erfindungsgemäßen Vorrichtung bei geöffneten Sack anschließend an die Position gemäß Fig. 2e.

The invention is explained in more detail below in principle by way of example with reference to the drawing. Show it:

• Figure 1 is an overall view of the device according to the invention.
• 2a to 2e an illustration of the main movements during the bag pick-up;
• _F ig. 3 shows a top view of a device according to the invention in a position according to FIG. 2e;
• _F ig. 4 shows a basic representation of the top view of a device according to the invention with the sack open, following the position according to FIG. 2e.

The device shown in FIG. 1 has a carousel 1 with an automatic bag trailer 2. A sack stack 3 is mounted on a table 4 (shown schematically), an adhesive drum 5 being held on guide columns 6 and 7 above the table. The drum 5 has a fulcrum 8 and suction cups 9 and can be rotated about its fulcrum by a pneumatic cylinder 10. The horizontal movement of the drum 5 is triggered by a pneumatic cylinder 11 which is articulated on a crossbar of the guide columns 6 and 7. The drum 5 is attached to the vertical machine stand 13 by means of a pull chain 12, which enables a smooth rolling movement when the bag is lifted in the positions from FIG. 2c to FIG. 2d. Furthermore, a clamping jaw 20 is provided which is slidably mounted horizontally above the pneumatic cylinder 21 on the guide columns 6 and 7, the cylinder 21 also being mounted on the crossbar of the guide columns 6 and 7. The clamping jaw 20 has suction cups 9 which are identical to those which are attached to the drum 5.

The entire unit of the guide columns 6 and 7 with the drum 5 and the clamping jaw 20 can be lowered and pivoted about a pivot point 22 by the pneumatic cylinders 23 and 24 be lifted. An end plate 25 describes an arc in a corresponding guide in the machine stand 13.

On the carousel 1, a nozzle 30 is shown (FIG. 1), on which a clamping device 31 can be opened and closed by means of a pneumatic cylinder 32. The representation of the carousel 1 is shown only schematically in FIG. 1 and on a smaller scale compared to the representation of the lower automatic bag trailer 2, the exact position of the two devices being rotated into the image plane.

The carousel 1 has a drive motor 33 and a gear 34, both of which are attached directly to the carousel 1 in such a way that an overdrive shaft 35 of the gear 34 forms the axis of rotation of the carousel. The material to be filled, e.g. B. flour, is passed via a funnel 36 into the opening 37 in the outlet nozzle 30 and fed directly from there into the attached sack. In order to be able to optimally coordinate all processes on the carousel 1, the clamping device 31 and the automatic bag trailer 2, all important control commands can be fed from a central control unit 38 via corresponding feed lines 39.

The movement sequences of the drum 5 are shown in FIGS. 2a to 2e, the starting position of the adhesive drum 5 relative to the bag stack 3 being recorded in FIG. 2a.

In the position shown in FIG. 2 b, the adhesive drum 5 has carried out a rotary movement by 90 ° around the pivot point 8, the movement being triggered above the cylinder 10. The drum 5 with the suction cups 9 is on the cylinder 23 together with the unit of Guide columns 6 and 7 lowered about the pivot point 22 on the bag stack 3. The suction cups 9 are placed under vacuum and then suck on the top sack, for. B. a paper or plastic bag.

As shown in FIG. 2d, the adhesive drum 5 then executes a rotary movement by 90 ° in a clockwise direction, which is triggered by the cylinder 11, which pulls the adhesive drum 5 backwards. At the same time, the pull chain 12, which rests rolled up over the adhesive drum 5, forces it onto a smooth movement sequence. The other end of the sack 40 is not moved during this movement.

• Zunächst wird die Klemmbacke 20 entsprechend Pfeil 41 horizontal nach rechts gerückt, anschließend die ganze Einheit über den Zylinder 23 (Pfeil 42) angehoben. Sodann findet ein horizontales Zu- bzw. Nach-Links-Schieben der Hafttrommel 5 (Pfeil 43) statt.

2e, the upper end of the sack 40 is brought into a vertical position. The sequence of movements is shown in FIG. 2e, the movements taking place in sequence as follows:

• First, the clamping jaw 20 is moved horizontally to the right in accordance with arrow 41, then the entire unit is lifted above the cylinder 23 (arrow 42). Then the adhesive drum 5 is pushed horizontally to the left or to the left (arrow 43).

The illustration according to FIG. 2e shows this latter phase, with the clamping jaw 20 and the adhesive drum 5 clamping the bag. The suction cups 9 of the jaw 20 are now also placed under negative pressure. This is the starting position for the position of the device shown in FIG. 3 in plan view and somewhat enlarged scale.

From Fig. 3 it can also be seen that the drum 5 is held on the guide columns 6 and 7 via supports 50 and sliding bearings 51. The clamping jaw 20 is also held displaceably on the guide columns 6 and 7 via a support 52 and a bearing 53.

4 shows the same device as in FIG. 3, but in the subsequent movement phase: the suction cups 9 are fastened to flexible leaf springs 54 and 55 both in the drum 5 and in the clamping jaw 20. These leaf springs are held over pressure rods 56 which engage the respective outer ends of the leaf springs. The leaf springs 54 and 55 are also attached in the middle to a tab 57 so that each spring is held at three points. The drive mechanism 58 has two toothed segments 59 and 60, which mesh with one another and thus ensure that both leaf spring ends are synchronized. The toothed segments 59 and 60 are fixed in the drum 5 approximately centrally at pivot points 61 and 62. The same also applies to the clamping jaw 20. The toothed segments 59 and 60 are actuated via a pneumatic cylinder 63 and 64, respectively. Here, the cylinder 63 drives the clamping jaw 20 to the left by the distance 2a via tooth segments 59 and 60 and a lever device 65 (arrow 66). At the same time, the cylinder 64 is pressurized and it pushes the spring ends over the corresponding toothed segments to the right, so that the sack 40 remains permanently clamped between the leaf spring ends at the lateral ends, but the opening of the sack assumes an approximately oval shape in plan view ( the opening shape shown in FIG. 4 is specifically referred to here). During this movement process, the cylinder 21 remains under pressure, but due to its lower force brakes the horizontal movement of the jaw 20 in the direction of arrow 66.

As can be seen from Fig. 1, the whole unit (guide columns 6, 7 and 8, drum 5 and jaw 20 with open bag 40) can be raised about the pivot point 22 by means of the cylinder 24, after which the upper ends of the bag between the outlet nozzle 30 and the clamping device 31 slide. The clamping device 31 then clamps the sack 40 firmly on the outlet nozzle 30. Thereafter, the vacuum on the suction cups 9 is removed, the entire unit lowers back into its starting position when the cylinder 24 is actuated, and a new movement cycle can begin.

In the device according to the invention, the device for individually removing the sacks from the sack magazine can already (simultaneously) grasp a new sack or prepare it for filling while the carousel 1 is still loading the (new) outlet nozzle 30 into the loading or standby Position.

Claims (19)

1. Device for the automatic filling of sacks at the outlet nozzle of a filling funnel, the empty sacks being stacked in a sack magazine in a horizontal position, with a suction device for individually removing the sacks from the sack magazine and for pivoting the respective sack into a substantially vertical hanging position, with a spreading device for widening the respective sack in its mouth area and with a holding device for clamping the sack mouth to the outlet nozzle, characterized in that the suction device for removing the sacks individually from the sack magazine (3) as a drum (5) provided with adhesives (9) is formed, which is horizontally displaceable in a frame (6, 7) so as to be rotatable about an axis (8) running parallel to the surface of the sacks (40) stored in the sack magazine (3) and perpendicular to their longitudinal axis and can be lowered onto the sacks in this way that by the adhesive (9) the top of the sack Sack magazine (3) in the vicinity of the bag opening can be detected. _2nd Device according to Claim 1, characterized in that the drum (5) can be rotated after it has been lowered onto the sacks and then activated by the adhesive means (9) to raise the end of the sack (40) on the opening side. _3. Apparatus according to claim 2, characterized in that the drum (5) can be raised during or after twisting. _4th Device according to claim 2 or 3, characterized in that the drum (5) rotates by 90 °. 5. Device according to one of claims 1 to 4, characterized by a with the drum (5) for widening the opening of the sack (40) cooperating clamping jaw (20) which can be merged with the drum (5) in the frame (6, 7 ) is stored and provided with adhesives (9) for gripping the opening-side bag end area facing away from the drum (5). ₆ . Device according to one of claims 1 to 5, characterized in that suction cups ( ₅ ) are provided as the adhesive. 7. The device according to claim 6, characterized in that the suction cups (5) with the interposition of leaf springs (54; 55) on the clamping jaw (20) or the drum (5) are attached. 8. Device according to one of claims 1 to 7, characterized in that the adhesive means (9) on the drum (5) as on the clamping jaw (20) are distributed over a width corresponding to the width of the sacks to be accommodated. 9. The device according to claim 7, characterized in that the leaf springs (54; 55) after mutual gripping of the opening-side bag end areas of the bag (40) by means of actuating elements (60 to 65) connected to them in an opening region of the gripped bag substantially oval widening Form can be brought. 10. Device according to one of claims 5 to 9, characterized in that the drum (5) and jaw (20) can be raised to an upper raised position after widening the bag opening and the open bag end area via the outlet nozzle (30) are guided. 11. The device according to claim 10, characterized in that the holding device (31) for clamping the bag mouth at the outlet nozzle (30) can only be actuated after the drum (5) and clamping jaw (20) have reached their upper lifting position. 12. Device according to one of claims 9 to 11, characterized in that the drum (5) and jaw (20) have pneumatic actuating means (11; 21). 13. The apparatus according to claim 12, characterized in that pneumatic cylinders (11; 21) are provided as the actuating means. 14. The apparatus according to claim 12 or 13, characterized in that the actuating means (11) for the drum (5) and (21) for the jaw (20) in fixed association with each other on the frame (6, 7) are attached. 15. The device according to one of claims 1 to 14, characterized in that a carousel (1) rotatable about a vertical axis by means of a motor ( ₃ 3) is provided with at least three outlet connections (30), which can be rotated in this way after a bag (40) has been connected to an outlet connection (30) in the loading position is that a new outlet connection (30) passes eladestellung in the _B. 1 ₆ . Apparatus according to claim 15, characterized in that the carousel (1) has four outlet connections (30) and can be rotated by means of a pole-changing motor (33). _17th Apparatus according to claim 15, characterized in that the motor (33) of the carousel (1) can be switched to a fast and a slow speed. 18. The apparatus according to claim 17, characterized in that the motor (33) is provided with a brake and one of its phases can be connected to a resistor. 19. Device according to one of claims 1 to 18, characterized by an optical detector for detecting the detection of a sack (40) by the drum (5).

Images