GB2111467A - Apparatus for feeding open bags to an installation for filling and subsequently closing the bags - Google Patents

Abstract

Apparatus for feeding open bags 1 individually to an installation for filling and subsequently closing the bags 1, comprises a separating means 4 for separating bags 1 from a store 15 of overlapping bags and means for conveying the bags 1 to a distributor means. The distributor means comprises a carriage 6, which is disposed downstream of the separating means 4 and which moves the bags fed individually thereto in a transverse direction alternately left and right to the respective fitting station 9 or 10 of two filling connections 11 or 12. The separating means 4 comprises pairs of grippers which are arranged in four pairs 3 on a cross 17 rotatable about a horizontal axis 24, the bags being fed from the store 15 to the cross 7 by an intermittently operated belt 16. <IMAGE>

Description

SPECIFICATION Apparatus for feeding open bags to an installation for filling and subsequently closing the bags The invention relates to apparatus for feeding open bags to an installation for filling and subsequently closing the bags.

The bags or sacks (hereinafter referred to as bags) which are filled by means of a filling device and closed by a closure device disposed downstream of the filling device, are stacked by means of automatic paletting machines to form transportable units. As the output of an automatic pea letting machine may be substantially higher than that of a filling device, the efficiency of such a piece of equipment is not satisfactory from the point of view of economic viability. There is therefore a need for a higher level of output from the installation, although that cannot be attained with previously proposed filling devices as their output depends in particular on the properties of the material being filled into the bags.

However, because of space requirements in most factories, it is not possible for an automatic paletting machine to have two filling devices associated with it, because of the space required for installing a second installation, since the filled bags are usually transported away from a filling station in a direction at right angles to the direction of feed of bags thereto.

In addition, there is no guarantee that, given the size of such an installation, one person can watch over and operate the installation. Further, the costs involved in installing a complete second filling device, with a device disposed upstream thereof for feeding the bags, and a bag closure station disposed downstream thereof, would be very high.

According to the present invention, there is provided apparatus for feeding open bags to an installation for filling and subsequently closing the bags, in which apparatus separating means separates individual bags from a store of overlapping bags and feeds the bags individually to distributor means, and the distributor means is disposed downstream of the separating means, moves the bags fed individually thereto in a direction transverse to the direction of movement of the bags by the separating means, and feeds the bags individually to a respective fitting station of two filling connections of the apparatus to be filled thereat and subsequently closed.

Such apparatus can have an output which corresponds to the output of an automatic paletting machine, and can be cheap to produce and compact in size.

Thus, two filling devices can be supplied from a bag storage means, such as a roll of bags, without detrimentally affecting the output of a single filling device. The costs of and the amount of space required by such an installation can be considerably reduced for the reason that the bag separating means and the bag distributor can be made from relatively simple components.

Advantageously, the separating means comprises grippers which are rotatable about a horizontal axis and which convey each respective bag, by gripping the end of the bag which emerges from the store in the direction of conveying movement, and move it from an approximately horizontal orientation into an approximately vertical orientation. In that way, the bags can be easily pulled off a roll and individually transferred to the distributor means. Particularly favourable conditions from the point of view of operational reliability, are provided by the grippers being arranged in pairs, and by four pairs of grippers being arranged rotatably about the horizontal axis, each bag being engaged by the grippers of one of the pairs of grippers, in the region of the outside edges or the leading edge of the bag.

The separating means is preferably of such a configuration that rollers are associated with the grippers in the region of the discharge end of a conveyor belt which conveys the bags in a mutually overlapping configuration (that is, adjoining bags overlap each other), the rollers rotating at a high speed to accelerate the trailing end of the bag. Thus, it is possible to attain the speeds required for separating the bags from each other, with a compact construction.

The grippers, which separate aut the bags from their mutually overlapping positions, may be produced in a particularly simple manner by each gripper of a pair of grippers being formed by a piston cylinder unit which is pivotal about a common point of rotation, and a support means. It is possible to provide a particularly simple and reliable construction if the pairs of grippers are arranged pivotally on a rotary cross member which is formed by four arms and which is secured on a horizontal shaft which defines the horizontal axis.

Advantageously, the distributor comprises a carriage which is movable between two limit positions and which is provided with two holding and conveyor means, for alternately feeding bags taken over by the rotary grippers to the two filling connections in such a way that one of the holding and conveyor means takes over a bag from the grippers, while the other of the holding and conveyor means discharges a bag to the respective fitting station. Such a construction permits two filling devices to be supplied with bags from one store of bags.

Each holding and conveyor means can comprise two grippers which engage the bag at the upper open end thereof, in the region of the edge of the mouth of the bag. A particularly simple mode of actuating the holding and conveyor means can be achieved by the holding and conveyor means being operable by a piston cylinder unit.

The apparatus can have a high output by virtue of the pairs of grippers which rotate about the horizontal axis, being driven in dependence on the operational readiness of the filling connection.

With that constructions, it is then possible, in the event of a breakdown in a filling means, for the feed of bags to that filling means to be interrupted, while the second filling means continues to operate, without delay. That applies in particular in regard to repairs which take up a prolonged period of time. In that case, it is particular advantageous for the pairs of grippers to be lockable. If the distributor is of such a design that the drive means for driving the carriage is formed by a piston cylinder unit, operating reliability is ensured.

The invention is diagrammatically illustrated by way of example, with reference to the drawings, in which Figure 1 is a schematic illustration of the operation of two filling devices supplied with bags from a single storage means in accordance with the invention; Figure 2 is a side view of a feed means of apparatus according to the invention wherein bags to be filled are separated from a roll; and Figure 3 is a view of part of the feed means of Figure 2, showing pairs of grippers which are rotatable about an axis.

Referring to Figure 1, ready-made bags 1, each of which is open at one end and which overlap each other, are fed to a bag singling or separating means 4 which is formed by pairs of grippers 3 rotatable about a horizontal axis 2, Each pair of grippers 3 comprises two grippers 3a and 3b which engage the leading end of each respective bag 1 having regard to the direction of conveying movement indicated by arrow A. Disposed downstream of the separating means 4 is a distributor means 5 which operates in a transverse direction with respect to the direction in which the bags are moved by the separating means 4, and which comprises a carriage 6 which is movable, between two limit positions, in the direction indicated by arrow B, and holding and conveyor means 7 and 8 which are arranged in pairs on the carriage 6.In Figure 1, the carriage is shown in solid lines in its righthand limit position, and in dash-dotted lines in its lefthand limit position.

The bags 1 are fed alternately by means of the distributor means 5 to two fitting stations 9 and 10, by means of which the bags 1 are fitted to filling connections 11 and 12. After the filling operation, the bags 1 are conveyed into closure stations 13 and 1 4.

In the apparatus illustrated in Figure 2, the bags 1, which are stored in a roll 15 and each overlap a following bag, are drawn off the roll 15 by means of a conveyor belt 1 6 which moves with an intermittent motion, and conveyed to the separating means 4 which is in the form of a rotary cross arrangement 1 7. The roll 1 5 is freely rotatably mounted on a stand 18. The conveyor belt 1 6 is pivotal about a horizontal axis 1 9. The upper pass 22 of the conveyor belt 16 is pressed against the periphery of the roll 1 5 by means of a piston cylinder unit 20 and a weight 21.

The rotary cross arrangement 17, which is formed by four arms 23, is fixed on a rotatably mounted shaft 24. The grippers 3a, 3b of the pairs of grippers 3 are arranged pivotally at the free ends of the arms 23. The grippers 3a and 3b on one of the arms 23 are pivoted inwardly and closed when that one of the arms moves into a vertically downwardly extending orientation. In that position, they engage the leading bag 1, that is to say the bag which is at the front in the direction of conveying movement. The bag 1 is pulled out of its position of overlap with the next following bag, by the onward movement of the separating means 4. When that takes place, the trailing end of the bag 1 is accelerated by rollers 25 which are rotating at a higher speed.The rotary cross arrangement 17, and therefore the grippers 3, have an intermittent motion in the direction indicated by arrow C. As each arm 23 reaches the leftward extending horizontal position, the bag 1 which it is holding is taken over by the holding and conveyor means 7 and 8 which are arranged in pairs on the carriage 6. The grippers 3a and 3b are opened and pivoted outwardly. The holding and conveyor means 7 and 8 comprise grippers 26 and 27 which are arranged in pairs and which engage the bag 1 from above in the region of the outside edges thereof. When the bag has been gripped by say the means 8, the carriage 6 which is connected to a piston cylinder unit 28 is moved into its other limit position by the piston cylinder unit 28.At the same time, the rotary cross arrangement 1 7 is advanced by one step, by means of a drive (not shown). The holding and conveyor means 8 then discharge the bag it is holding to the fitting station 10, while at the same time a bag is taken over from a pair of grippers 3, by the holding and conveyor means 7. After the carriage has moved to its other limit position, the bag gripped by the holding and conveyor means 7 is discharged to the fitting station 9, while the holding and conveyor means 8 takes over a bag from the next following pair of grippers 3. In Figures 2 and 3, the bag which is discharged at the fitting station 9 or 10 respectively is indicated by reference numeral la.

As shown in Figure 2, a filling device 29 comprises a carriage 32 which is provided with grippers 30 and spreader fingers 31, an opening, station 33 (not described in detail herein) and a pair of downwardly movable filling connections or nozzles 11 and 1 2 respectively, provided with spreader flaps 34 and clamping jaws 35.

Disposed below each filling connection 11 and 12 is a slat-type conveyor belt 37 for carrying away the filled bags 1.

For the purposes of taking over the bag 1 a, the carriage 32 is in the position shown in dashdotted lines in Figure 2. The grippers 30 take over the bag 1 and transport it into the region of the opening station 33. After the bag 1 is opened, the spreader fingers 31 take over the bag 1, the carriage 32 again being in the position shown in dash-dotted lines in Figure 2. By movement of the carriage 32, the bag 1 is then moved under the filling connection 11 or 12 respectively, clamped to the clamping jaws 35 by downward movement of the filling connection 11 or 12 respectively and a spreading movement of the spreader flaps 34, filled and subsequently closed. Control means (not described in detail herein) ensures that bags 1 are fed to each filling device 29 only when operational readiness of the filling connection 11 or 12 respectively is signalled by means of a suitable signal. The bag feed means is interrupted by a drive means, controlled by the signal, for the rotary cross arrangement 17, and by a control action in respect of the grippers 3a and 3b. It is also possible for one filling connection 1 or 12 to be stopped, while the other filling connection 11 or 1 2 respectively is in operation.

Claims (12)

Claims

1. Apparatus for feeding open bags to an installation for filling and subsequently closing the bags, in which apparatus separating means separates individual bags from a store of overlapping bags and feeds the bags individually to distributor means, and the distributor means is disposed downstream of the separating means, moves the bags fed individually thereto in a direction transverse to the direction of movement of the bags by the separating means, and feeds the bags individually to a respective fitting station of two filling connections of the apparatus to be filled thereat and subsequently closed.

2. Apparatus according to claim 1, wherein the separating means comprises grippers which are rotatable about a horizontal axis and which transport each respective bag, by gripping the end of the bag which emerges from the store, in the direction of conveying movement, and moving it from an approximately horizontal orientation into an approximately vertical orientation.

3. Apparatus according to claim 2, wherein the grippers are arranged in pairs, four pairs of grippers are arranged rotatably about the horizontal axis, wherein each bag is engaged by one of the pairs of grippers in the region of the outside edges or the leading edge.

4. Apparatus according to claim 2 or claim 3, in which rollers are associated with the grippers, and are located in the region of the discharge end of a conveyor belt which conveys the bags which mutually overlap, the rollers being rotated at a speed which causes acceleration of the trailing end of the bag.

5. Apparatus according to claim 2, claim 3 or claim 4, wherein each gripper of a pair of grippers is formed from a piston cylinder unit which is pivotal about a common point of rotation and a support means.

6. Apparatus according to any one of claims 2 to 5, wherein the pairs of grippers are arranged pivotally on a rotary cross member which is formed by four arms, secured on a horizontal shaft defining the horizontal axis and being intermittently driven.

7. Apparatus according to any one of the preceding claims, wherein the distributor means comprises a carriage which is movable between two limit positions and which is provided with two holding and conveyor means for alternately feeding bags taken over from the rotary grippers to the two filling connections in such a way that one of the holding and conveyor means takes over a bag from the grippers, while the other holding and conveyor means discharges a bag to the respective fitting station.

8. Apparatus according to claim 7, wherein the open end of each bag is uppermost when in the vicinity of the holding and conveyor means, and each of the holding and conveyor means comprises a pair of grippers which engage the bag at the upper open end thereof, in the region of the edge of the mouth of the bag.

9. Apparatus according to claim 7 or claim 8, wherein the holding and conveyor means are actuable by a piston cylinder unit.

10. Apparatus according to claim 7, claim 8 or claim 9, wherein the drive for the carriage is formed by a piston cylinder unit.

11. Apparatus according to any one of the preceding claims, wherein the pairs of grippers, which rotate about the horizontal axis, are driven in dependence on the operational readiness of the filling connections.

12. Apparatus according to any one of the preceding claims, wherein the pairs of grippers are of a lockable construction.

1 3. Apparatus for feeding open bags to an installation for filling and subsequently closing the bags substantially as hereinbefore described and illustrated with reference to the accompanying drawings.