GB2065591A

GB2065591A - Applying open-topped bags to a filling nozzle and compressing a substance dispensed into the bags

Info

Publication number: GB2065591A
Application number: GB8039719A
Authority: GB
Original assignee: Haver and Boecker OHG
Current assignee: Haver and Boecker OHG
Priority date: 1979-12-17
Filing date: 1980-12-11
Publication date: 1981-07-01
Also published as: GB2065591B; DE2950821A1; FR2471916A1; AT386579B; FR2471916B1; DE2950821C2; ATA550980A

Abstract

A bag filling machine wherein bags to be filled are individually brought along a path 7 to a filling nozzle 2 and are clamped to the nozzle 2. Pressure bars 8, 19, extending transversely of the feed path, are provided one on each side of the bag and are movable towards and away from each other by cylinders 16, 20. To permit use of bags of stiff material which cannot be y pulled over the top of the pressure bar 8, the pressure bar 8 is longitudinally movable (to the full line position) out of the feed path 7 of the bag and is returned (to the dotted line position) after the bag has passed to the nozzle (7). In like manner, the back-pressure plate 34 of a compacting device comprising a vibratory plate 41 and plate 34 is also longitudinally movable out of the path of the bag. After the bag is filled the pressure bars 8, 19, which are mounted on a common support frame 27, can be moved laterally together and pivoted downwardly about an horizontal axis (28) to expel air from the bag. <IMAGE>

Description

SPECIFICATION Method and apparatus for applying opentopped bags to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags The invention relates to a method and apparatus for applying open-topped bags, preferably paper or plastic bags with side folds, to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags.

The method and apparatus employ two pressure bars which engage opposite sides of the bag and which can be moved in a region between the nozzle and the filled substance, and also employ two plates which are arranged parallel with the pressure bars and which engage the bag in the filling region.

That one of the plates provided at the feed side of the bag is preferably constructed as a back-pressure plate and the other as a vibrating plate.

Machines of this kind, for applying opentopped flat bags to a filling nozzle of a filling machine, for filling the bags and for compressing the substance dispensed, have been previously proposed. At the filling station the top edge of the filled bag is spread out flat by a spreader, the ar above the filling is pressed out by the pressure bars mounted pivotably below the nozzle, and the top edge of the bag is guided automatically into a sealing machine on a transporting line.

Machines ef this kind are also used for plastic bags with side folds, provided that the plastics material of the bags is flexible enough to enable the bag applied to the nozzle to be pulled from outside, e.g. with a push rod, a sufficient distance over the swung-out pressure bar for the remaining part of the bag to be pulled downwards by the weight of the substance filied into the bag so as to be moved into the filling position without diffi culty.

Paper bags and bags made from thickwalled sheets with side folds cannot be used in this way. With them it is necessary for the bag to be guided in a free-hanging position on its way to the filling nozzle instead of being pulled over a pressure bar.

According to one aspect of the invention there is provided a method of applying opentopped bags to a filling nozzle of a filling rnachine and for compressing a substance dispensed into the bags, wherein two pressure bars are engageable with opposite sides of the bag and are movable in a region between the nozzle and the substance filled into the bag, and two plates are disposed to extent parallel with the pressure bars and are engageable with opposite sides of the bag in the filling region, that one of the plates provided at the side of the bag from which the bags are fed in preferably being constructed as a back-pressure plate and the other as a vibrating plate, the method including, prior to application of the bag to the filling nozzle, moving that one of the pressure bars and that one of the plates provided at the bag feed side out of the feed path of the bag; after the bag has passed to the filling nozzle moving said one of the pressure bars and said one of the plates back into the bag region, and, when the bag has been filled, moving both of the pressure bars to expel air contained in the bag above the substance filled into the bag, by effecting pivoting movement of a common support for the pressure bars.

By means of such a method bags, even with side folds and/or made of thick-walled paper or plastic sheets, possibly in combination with metal foil, can be applied reliably to the filling nozzle of a filling machine and then further processed.

According to a further aspect of the invention there is provided apparatus for applying open-topped bags to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags, comprising two pressure bars transversely movable to engage them with opposite sides of the bag and movable in a region between the nozzle and the substance filled into the bag, and two plates disposed to extend parallel with the pressure bars and engageable with opposite sides of the bag in the filling region, wherein that one of the plates provided at the side of the bag from which the bags are fed in, is movable out of the feed path of the bag, that one of the pressure bars provided at the bag feed side is mounted for movement parallel with the longitudinal central plane of the nozzle and transversely to its longitudinal axis by mounting it on a support, whereby said one of the pressure bars can be moved out of the feed path of the bag, and, the other of the pressure bars is also mounted on said support and said support can pivot about an axis extending parallel with the longitudinal centre plane of the nozzle so that, after the bag has passed to the filling nozzle, said one of the pressure bars can be moved back into the bag region, and, after the bag has been filled and to expel air contained in the bag above the substance filled into the bag, the two pressure bars can be pivoted by pivoting movement of the common support.

In the method and apparatus of the invention, free access to the filling nozzle of the filling machine is provided for application of the bag, so the bag can be applied to the filling nozzle even if it is made of stiff mate rial.

The invention is diagrammatically illustrated by way of example in the accompanying drawings, in which: Figure 1 is an elevation of apparatus according to the invention; and Figure 2 shows a plan view of the apparatus of Fig. 1.

Referring to the drawings, a filling machine 1 has a filling nozzle 2, equipped with spreader flaps 3 and clamping jaws 4. The jaws 4, which fix the top edge of a bag to be filled to the nozzle, are actuated by a compressed air cylinder 5.

In Fig. 1 the jaws 4 are shown in the swung-out position, so that a bag 6 can be moved up in the direction of the arrow 7 and applied to the filling nozzle 2. When it has been applied to the nozzle the jaws 4 grasp its upper edge and secure it relative to the spreader flaps 3. The flaps 3 can then be opened for the bag to be filled.

In Fig. 2 the rectangular cross-section of the filling nozzle 2 is shown in dash-and-dot lines.

The feed side of the bag is indicated by the arrow 7. A pressure bar 8 is provided at the bag feed side and extends parallel with the longitudinal centre plane 9 of the nozzle 2.

The bar 8 is fixed to an angular arm 10 which is attached to the ends of two rods 11 which are mounted so as to slide in sleeves 1 2. The sleeves 1 2 are fixed to a carriage 13, which is mounted so as to slide along guide rods 14, 1 5 extending parallel with the pressure bar 8 and with the longitudinal centre plane 9. The carriage 1 3 also carries a displacement cylinder 1 6 for moving the bar 8 transversely to its longitudina! axis. The cylinder has a piston rod 1 7 with its free end fixed to a transverse web 18, to which the ends of the rods 11 are attached. The cylinder 1 6 is preferably operated with compressed air.

At the side opposite the feed side of the bag there is a pressure bar 1 9. This can be moved transversely to its longitudinal axis by a displacement cylinder 20. The bar 1 9 is fixed to an angular arm 21, which has rods 22 attached to it, the rods being mounted so as to slide in sleeves 23. The ends of the rods 22 away from the bar 1 9 are fixed to a transverse web 24, which is engaged by a piston rod 25 of the displacement cylinder 20. The cylinder 20 and sleeves 23 are fixed on a crossbar 26 which is in the form of a profiled bar. The pressure bars 8 and 1 9, with their guide means and displacement cylinders for the transverse movement, are arranged on a common support 27, which can be pivoted about an axis 28 by means of a compressed air cylinder 29.

The support 27 is constructed as a frame, with a front strut formed by the guide rod 14.

Side struts 30 and a rear strut 31 comprise profiled bands. The crossbar 26, carrying the sleeves 23 and displacement cylinder 20, is fixed to the side struts 30.

The pivot pin 28 is formed by the guide rod 15, which is supported at its ends in bearings 32.

A composed air cylinder 33 is provided to reciprocate the carriage 1 3. By means of the cylinder 33 the pressure bar 8 is moved behind the bag from the position drawn in full lines in Fig. 2, after the bag 6 which has to be applied to the nozzle 2 has passed the bar 8. In this operative position the bar 8 would prevent free access to the nozzle, which is shown in Fig. 2. A back-pressure plate 34 is moved simultaneously with the bar 8 and transported to a position adjacent the nozzle 2. In said position it would similarly prevent a bag from having free access to the nozzle. The back-pressure plate 34 is fixed to a carriage 35 mounted to be moved along guide shafts 36 by means of a compressed air cylinder.

The back-pressure plate 34, extending parallel with the longitudinal centre plane 9, is disposed on a stand 37 of an under-frame 38 of a belt 39, by means of which belt 39 filled bags can be carried away.

On the opposite side of the bag to the backpressure plate 34, a stand 40 for a vibrating plate 41 is similarly mounted on the underframe 38 of the discharge belt 39.

It will be seen from Fig. 1 that the vibrating plate 41 and back-pressure plate 34 support the bag 6 when it is at the filling station.

Fig. 2 shows that the vibrating plate 41 extends beyond the filling station in the direction in which the filled bags are moved away (indicated by the arrow 42). The positions to which the pressure bars 8 and 1 9 are moved transversely to bring them together is shown in dash-and-dot lines in Fig. 2. From this position, by a pivoting movement of the frame support 27 about the axis 28 (Fig. 1) the pressure bars 8, 1 9 are moved downwardly to the dotted line positions of Fig. 1 so that air above the substance filled into the bag is pressed out of the bag.

The pressure bars 8 and 1 9 and the backpressure plate 34 are thereafter moved back to the positions shown in full lines in Fig. 2.

The upper edge of the bag is initially spread out by fingers 43 which enter the mouth of the bag. The spread-out position of the fingers 43 is shown in Fig. 2.

Claims

1. A method of applying open-topped bags to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags, wherein two pressure bars are engageable with opposite sides of the bag and are movable in a region between the nozzle and the substance filled into the bag, and two plates are disposed to extend parallel with the pressure bars and are engageable with opposite sides of the bag in the filling region, that one of the plates provided at the side of the bag from which the bags are fed in preferably being constructed as a back-pressure plate and the other as a vibrating plate, the method including, prior to application of the bag to the filling nozzle, moving that one of the pressure bars and that one of the plates provided at the bag feed side out of the feed path of the bag; after the bag has passed to the filling nozzle moving said one of the pressure bars and said one of the plates back into the bag region, and, when the bag has been filled, moving both of the pressure bars to expel air contained in the bag above the substance filled into the bag, by effecting pivoting movement of a common support for the pressure bars.

2. Apparatus for applying open-topped bags to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags, comprising two pressure bars transversely movable to engage them with opposite sides of the bag and movable in a region between the nozzle and the substance filled into the bag, and two plates disposed to extend parallel with the pressure bars and engageable with opposite sides of the bag in the filling region, wherein that one of the plates provided at the side of the bag from which the bags are fed in, is movable out of the feed path of the bag, that one of the pressure bars provided at the bag feed side is mounted for movement parallel with the longitudinal central plane of the nozzle and transversely to its longitudinal axis by mounting it on a support, whereby said one of the pressure bars can be moved out of the feed path of the bag, and, the other of the pressure bars is also mounted on said support and said support can pivot about an axis extending parallel with the longitudinal centre plane of the nozzle so that, after the bag has passed to the filling nozzle. said one of the pressure bars can be moved back into the bag region, and, after the bag has been filled and to expel air contained in the bag above the substance filled into the bag, the two pressure bars can be pivoted by pivoting movement of the common support.

3. Apparatus according to claim 2, in which the support is constructed as a frame, a front strut of which is a guide rod and a rear strut and side struts of which comprise profiled bands, said axis of pivoting of the support being formed by a further guide rod, and, a carriage which carries said one of the pressure bars is mounted to slide on both the guide rod and the further guide rod.

4. Apparatus according to claim 3, in which guide means for said one of the pressure bars and a displacement cylinder to cause the transverse movement are provided on the carriage.

5. Apparatus according to claim 4, in which the guide means comprise a sleeve fixed to the carriage and a rod mounted therein, and the outer end of the rod is connected to the pressure bar by an arm while the inner end of the rod is fixed to a transverse web, which is engaged by the piston rod of the displacement cylinder.

6. Apparatus according to any one of claims 3 to 5, including a compressed air cylinder to drive the carriage along the frame.

7. Apparatus according to any one of claims 3 to 6, in which the frame has a profiled cross bar fixed to the side struts and disposed between the guide rod and further guide rod, and further guide means and a further displacement cylinder for the other of the pressure bars, for moving that bar transversely to its longitudinal axis, are fixed on the crossbar.

8. Apparatus according to claim 7, in which the frame is movable about its axis of pivoting by means of a compressed air cylinder.

9. Apparatus according to any one of claims 2 to 8, in which said one of the plates is a back-pressure plate fixed to a carriage which can be moved along guide shafts by means of a compressed air cylinder.

10. Apparatus according to claim 9, in which the other of the plates is a vibrating plate which extends beyond the filling station in the direction in which the filled bags are transported away.

11. A method of applying open-topped bags to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags as claimed in claim 1 and substantially as hereinbefore described.

1 2. Apparatus for applying open-topped bags to a filling nozzle of a filling machine and for compressing a substance dispensed into the bags substantially as hereinbefore described and illustrated with reference to the accompanying drawings.