CA2295359A1

CA2295359A1 - Machine for conveying a pre-folded packing box blank in a packaging machine

Info

Publication number: CA2295359A1
Application number: CA 2295359
Authority: CA
Inventors: Bruno Jaksch; Georg Franta
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-01-14
Filing date: 2000-01-13
Publication date: 2000-07-14
Also published as: DE19901238B4; DE19901238A1; EP1020356A1

Abstract

The invention relates to a machine for conveying a pre-folded packing box blank (8) in a packaging machine. The packing box blank has a lid section and a bottom section, and therebetween a first side wall section and on the side of the lid section that is furthest from the first side wall section a second side wall section (26), the side wall sections being folded in the same direction out of the plane of the lid section. The machine incorporates conveyor devices (34, 35) which revolve in the region of the side wall sections and are arranged in the conveying direction (4) of the packing box blank. These conveyor devices accommodate driving dogs (37, 38), with a respective pair of driving dogs in each case locating between them one of the two side wall sections (26) in the region of the end faces (30) of said side wall section.
This configuration of the machine makes it possible to convey pre-folded packing box blanks in a defined manner in a packaging machine, in order to be able to perform manipulations on the respective packing box blanks, for example additional folding operations, glue application or the like.

Description

Herr Helmut Seidel Fliederstrasse 19 65396 Walluf Machine for conveying a pre-folded packing box blank in a packaging machine D a s c r i p t i o n The packaging of products is for example done by first of all forming the packing box to a large extent and placing the product into the latter, before then sealing the packing box, or else using the wrap-around method, in which the packaging is folded around the product. The present invention is concerned with the set of problems presented by the latter. The product may be a single article, for example a pizza, or else a plurality of products, in particular products stacked one on top of the other. The definition of product is for example also intended to include goods fitted into a bag and which are to be provided with outer packaging. One example would be cornflakes filled into bags, the bag being packed into a carton.
When a pre-folded packing box blank is conveyed in a packaging machine, the exact positioning of the packing box blank presents problems. This is true especially in light of the fact that both the packing box blank and the product are being carried along, and in particular they move in synchronism. Besides, conveying the pre-folded packing box blank in a precise manner is a pre-requisite for being able to accurately perform manipulations on the respective packing box blank, for instance additional folding operations or the application of glue in a defined area of the packing box blank in order to glue sections of the packing box blank to one another.
From unexamined German patent application DE-OS 27 14 584 a machine is known for moving packing boxes along a path, said machine being equipped with a device for sealing the packing box. The packing boxes are shifted along a worktable by driving fingers which operate on the same side of the packing box over a large surface thereof.
Thus the driving fingers operate on the rear vertical surface of the packing box, based on the conveying direction thereof. On the surface remote from said surface, i.e. the front surface of the packing box, there is provided a driving finger which runs ahead of the packing box and is used to additionally hold or secure the box in place against tipping over, etc.. The packing box is not locked in position by the driving fingers, and more particularly it is not gripped on the end face in the region of a side wall section.
It is the object of the invention to create a machine that enables folded packing box blanks to be conveyed in a defined manner in a packaging machine, so as to enable manipulations to be performed on the respective packing box blank, for example additional folding operations, glue application or similar.
The invention proposes a machine for conveying a pre-folded packing box blank in a packaging machine, the packing box blank having a lid section and a bottom section and therebetween a first side wall section and a second side wall section on the side of the lid section that is furthest from the first side wall section, the side wall sections also being folded in the same direction out of the plane of the lid section, with the following additional features:
- revolving conveyor devices are arranged in the region of the side wall sections in the packing box blank conveying direction;
- the conveyor devices receive driving dogs, with each pair of driving dogs locking one of the two side wall sections between them in the region of the end faces of said side wall section.
Thus the invention provides for the pre-folded packing box blank to be held in the region of the two side wall sections thereof, thereby enabling additional packing box blank folding operations to take place in a precise manner, in particular in relation to the bottom section or a tab section of the packing box blank to be glued to said bottom section. The side wall sections are exactly positioned relative to one another while the packing box blank is being conveyed, more particularly being disposed parallel to one another. Thus this ensures that as the bottom section is being folded it can, in the region of its free end edge, be placed flush or with slight parallel spacing to the plane of the associated side wall section, against the tab section that is joined to the side wall section, and there glued, or alternatively the tab section that is joined to the bottom section can be brought into a defined position to the nearest side wall section, in order to be glued thereto. The fact that the side wall sections are held in position by means of the driving dogs permits a high degree of dimensional stability of the packing box being additionally pre-folded, and this is a pre-requisite for the folding operations which follow, in particular the folding of end wall sections before the packing box is finally sealed.
As a general rule, packing box blanks have dust flaps joined to the end faces of the side wall sections, these flaps resting internally against the end wall sections as the latter are folded. In this context the driving dogs have the job not only of holding the side wall sections in position at the ends, but also of holding the dust flaps in their inwardly directed position and transferring them to a position in which they are directed slightly towards one another. The dust flaps thus serve more or less as spacers between the lid section and the bottom section or load-bearing section, thereby enabling them to help to align the bottom section during the act of folding it towards the lid section. It is considered to be particularly advantageous if the driving dogs are heel-shaped projections, with the heels of the leading and trailing driving dogs of the respective pair of drivers being directed at one another. When the dust flaps are folded into position they for instance adopt an angle of 50 to 80° to the associated side wall section. With regard to the centring function alluded to earlier, the driving dogs should extend to a height that is only slightly less than the height of the side wall sections.
It is considered to be particularly advantageous if, of the pair of driving dogs, the leading driving dog in the conveying direction and the trailing driving dog in the conveying direction are joined to different conveyor devices. The existence of different conveyor devices makes it possible to convert the packaging machine in a straightforward manner for different sizes of packing boxes, by adjusting the spacing between the dogs of the driving dog pair.

_ . CA 02295359 2000-O1-13 As a general rule each conveyor device will accommodate a plurality of driving dogs, thereby enabling a plurality of packing box blanks to be conveyed along simultaneously.
One particular refinement of the invention provides for the respective trailing driving dog in the conveying direction to be brought into position so as to hold the associated side wall section in place in the conveying direction. The packing box blank is carried into the entrance zone of the conveyor apparatus according to the invention by means of a separate conveyor device, which is for example in the form of a toroidal belt, the packing box blank being moved against the leading dogs in the region of these leading extremities of the side wall sections and the trailing dogs then being moved behind the side wall sections and brought into position against the end wall sections. In order to achieve this, the positionable driving dog may be held in the conveyor device in a manner allowing it to be pivoted, with the dog being moved along a stationary guide to bring it into position. The driving dog comes up against the stationary guide and is pivoted in the positioning direction. So that the respective positionable dog can only be pivoted in the defined manner, stops should be provided to limit the pivoting movement thereof. It is regarded as particularly advantageous if the stationary guide for positioning the driving dog takes the form of a restraint.
It is for example configured as a groove into which a pin joined to the driving dog engages.
One particularly simple design in constructional terms, which in particular can be constituted in the packaging machine in a straightforward manner, results if the conveyor device is constructed as a revolving chain, especially a horizontally revolving chain. The various conveyor devices are expediently arranged one above the other, and the driving dog ( s ) of the upper conveyor device are downwardly orientated and the driving dogs) of the lower conveyor device are upwardly orientated, in the manner in which they are fastened to the respective conveyor device. The conveyor devices are expediently powered by the same drive unit.
Additional features of the invention are represented in the Claims, in the Description of the Figures, and in the Figures themselves, it being noted that all the features and individual features are essential to the invention.
The invention is represented by means of an exemplifying embodiment, though without being confined thereto, in the Figures, wherein:
Fig. 1 shows a side view of a packaging machine which incorporates the apparatus according to the invention for conveying the pre-folded packing box blank;

Fig. 2 shows a plan view of the packaging machine shown in Fig. 1, which in zone VII incorporates the apparatus according to the invention;

Fig. 3 shows an as yet unfolded blank which rests in the region of its lid section on a conveyor device;

Fig. 4 shows the packing box blank, pre-folded in the manner according to the invention, in the region of the handover point from the lower conveyor device to the lateral driving dogs in accordance with the invention;

Fig. 5 shows the packing box blank with the bottom section virtually fully folded in the direction of the lid section;

Fig. 6 shows a section taken along line VI-VI in Fig.

5, including the driving dogs acting on the depicted side of the packing box;

Fig. 7 shows a general view of the conveyor devices which accommodate the driving dogs;
Fig. 8 shows a scaled-up detail of the conveyor device;
Fig. 8a shows a section taken along line VIII A-VIII A
in Fig. 8; and Fig. 9 shows a section taken along line IX-IX in Fig.
7 to clarify the adjustment of the chains accommodating the various driving dogs.
In Figures 1 and 2 the essential components of the packaging machine are depicted in a highly simplified form. The packaging machine has an incoming double chain 1 with driving dogs 2 which engage between mounting rails disposed parallel to one another, upon which rest pizzas 3. The respective pizza 3 is displaced in the conveying direction 4 by means of two driving dogs 2 which form a pair. A height guard 5 detects the height of the respective pizza and co-operates with an expulsion unit 6 which expels pizzas that are too high. Arranged above the incoming double chain 1 is a magazine 7 which accommodates a large number of plane blanks 8. Fig. 3 shows one such blank. A rotary placement device 9 takes whichever blank 8 is at the front out of the magazine 7 using suction devices (not separately numbered), and deposits it on lateral guides (not specifically shown). The movement of the rotary placement device 9 and of the incoming double chain 1 is synchronised in such a way that, as can be taken from the view shown in Fig. 1, the respectively deposited blank 8 slightly overlaps adjacent transverse dividers 2 of the incoming double chain 1. The blank 8 is deposited transversely to its conveying direction onto the lateral guides and is a short distance from the pizza 3 situated below it. The respective blank 8 is conveyed by means of a circular belt conveyor 10 disposed above the latter. Provided to the side of the incoming double chain 1 in the region of the circular belt conveyor 10 are devices (not shown) which transfer the respective blank 8 _ . CA 02295359 2000-O1-13 into the pre-folded position according to the invention, as is depicted in Fig. 4 and will be detailed further below. Following on from the incoming double chain 1 is a further conveyor device 13 for the pizzas 3, which incorporates a rear conveyor section 14 and a front conveyor section 15, between which an interspace 16 is disposed. As may be taken from the view in Fig. 2 in particular, a strut 17 is associated with the interspace 16 and its job is to continue folding the pre-folded packing box blank 8. In the region of this conveyor device 13 the respective blank 8 is no longer conveyed by means of the circular belt conveyor 10, but provided at that point is the conveyor device 13 of the invention, which will be described below in detail. In the region of the conveyor device 13 the respective blank 8 is folded and glued to the extent that it now remains only to close the end wall sections of the packing box. After the conveyor device 13 a rotation device 18 is provided, in which the particular packing box containing the pizza 3 is rotated through 90 ° , thereby enabling the end faces of the packing box to be closed in the following zone 19 of the packaging machine, which incorporates an outgoing double chain 20. This is followed by a discharging conveyor 21 which conveys the packaged pizzas out of the packaging machine.
Fig. 3 illustrates the design of the blank 8 used with the packaging machine. This blank 8 has a bottom section 22 and a lid section 23, which are of a matching square shape and are joined to one another by means of a rectangular side wall section 24 in the region of the fold lines 25.
On the side remote from the side wall section 24, the lid section 23 has a further matching side wall section 26, with a fold line 27 located between the side wall section 26 and the lid section 23. A tab portion 28, which will subsequently be used for gluing to the bottom section 22, is joined to the side wall section 26 via a fold line 29.

Dust flaps 31 are also joined via fold lines 30 at the ends to the side wall sections 24 and 26. End wall sections 33 are joined to the bottom section 22 and to the lid section 23 via fold lines 32 both on the leading and trailing face of the blank 8.
Fig. 3 shows the as yet unfolded blank 8, which is placed in such a way above the rear conveyor section 14, which carries along the circular pizza 3, that the centre of the pizza 3 essentially coincides with the diagonal point of intersection of the lid section 23. The blank 8 is orientated at a right angle to the conveying direction 4.
The aforementioned devices (not shown) convert the blank 8 into the pre-folded state, by virtue of the blank 8 being folded, through 90° in each case, in the region of the fold line 25 situated between the lid section 23 and the side wall section 24 and around the fold line 29 situated between the tab portion 28 and the side wall section 26, and the fold line 27 situated between the side wall section 26 and the lid section 23. The result is thus the pre-folded state of the blank 8 as shown in Fig.
4, the blank 8 and the pizza 3 being transported onward during the aforementioned folding operations. The pizza 3, and the blank 8 pass into the zone of the packaging machine that incorporates the interspace 16, in the region of which the bottom section 22 is to be folded up towards the lid section 23. There the blank is no longer conveyed by means of the circular belt conveyor 10, but instead the pre-folded blank is held in the region of the side wall sections 24 and 26. First of all, however, means (not shown) bend the dust flaps 31 inwards along their fold lines 30.
Fig. 2 shows a schematised version of the arrangement of the conveying apparatus according to the invention, while Figs . 6 to 8 and 8a illustrate said conveying apparatus in detail. In the region of the folding station incorporating the strut 17 for folding up the bottom section 22, there are arranged two horizontally revolving chains 34 and 35 on either side of the conveying apparatus 13, that is to say of both the rear and the front conveying section, 14 and 15 respectively. The chains 34 and 35 are conducted around a large number of corner pulleys 36. Leading driving dogs 37 are rigidly fastened on the respective chain 34. A large number of trailing driving dogs 38 are swivel-mounted on the respective chain 35. The chains 34 and 35 are arranged one above the other, with the driving dogs 37 fastened to the upper chain 34 being orientated downwards and the trailing driving dogs 38 fastened on the associated chain 35 being orientated upwards. The driving dogs 37 and 38 are thus operative at the same level. They are heel-shaped constructions, with the heels 39 of the leading and trailing dogs 37, 38 directed at one another. Based on a line perpendicular to the conveyor device 4 of the chains 34 and 35, the heels exhibit an angle a of 10 to 40°.
Fig. 7 illustrates diverse blanks 8 handled by the conveyor device according to the invention as they are being conveyed by the conveyor device 13. The situation in the incoming zone of the conveyor device is illustrated in detail in. Fig. 8. The blank 8 with the inwardly bent dust flaps 31 is moved by means of the circular belt conveyor 10 against the driving dogs 37 arranged on both sides of the blank. The shape of the respective driving dog 37 means that the associated dust flap 31 is folded into the overlaid position as soon as the dust flap 32 makes contact with the driving dog 37. The swivel-mounted trailing driving dogs 38 reverse their direction in the region of the respective rear corner pulley 36. The respective driving dog 38 is mounted in the chain 35 so as to be able to pivot on an axis 40, and permanently joined to the chain 35 is a plate 41 which is provided with a stop pin 42. This pin 42 passes through a slot 43 in the trailing driving dog 38. As a result of the co-operation of the stop pin 42 with the slot 43, the degree to which the trailing driving dog 38 is able to pivot is thus limited. Arranged beneath the upper chain section 44 of the trailing chain 35 is a plate-shaped stationary guide 45 which has an inclined rear guide section 45a and a front guide section 45b which extends parallel to chain section 44. In the zone in which the trailing chain 35 leaves the rear corner pulley 36 associated therewith, the pivotable, trailing driving dog 38 passes into contact with the inclined guide section 45a, with the result that it is pivoted for as long as it slides over the inclined guide section 45a. Once the trailing driving dog 38 reaches the straight guiding section 45b of the guide 45, it is supported thereon and is thus moved along the guide 45 in the manner of the fixed leading driving dog 37. As the trailing dog 38 is transferred from one to the other swivel position, it engages behind the trailing end of the associated end wall section; in Fig. 8 this is shown as side wall section 26. It goes without saying that the foregoing only applies to the driving dogs 37 and 38 passing into engagement with the other side wall section 24. The trailing driving dogs 38 also transfer the associated dust flap 31 into the overlaid position at the indicated angle a. From the view shown in Fig. 8a it can be seen that the height of the respective driving dog 38 - and this applies analogously to driving dog 37 - matches the height of the associated side wall section, 24 and 26 respectively. The height of the respective driving dog is slightly less than that of the associated side wall section. If, as depicted in Fig. 6 in particular, the driving dogs 37 and 38 grip the front ends of the side wall section, 24 and 26 respectively, in the region of the fold lines 30 the latter make contact with the depressions 46 directed away from one another in the driving dogs . On account of the heightwise extension of the driving dogs 37, 38, they - and likewise also the dust flaps 31 folded overlaid inwards - are in a position to centre the bottom section 23 folded beneath the lid section 23 as the box travels through the zone of the conveyor device. The driving dogs 37 and 38 fix the packing box blank 8 continuing to be pre-folded in position, with the result that after glue has been applied to the underside of the tap portion 28 the bottom section 22 can be pressed in alignment against tab portion 28. It is then only necessary to seal the ends of the by now largely folded packing box containing the pizza 3.
Figs. 7 and 8 illustrate the drive unit for the chains 34 and 35, as well as the device for adjusting chain 34 with the leading driving dog 37. The driving power is supplied via a cardan shaft 47 which drives an input shaft 48 to which a gear 49 is connected in a manner locked against rotation. Meshing with this gear is a chain 58 which drives a corresponding input shaft of the other chains 34 and 35. The input shaft 48 is rotatably mounted in a bearing plate 50. The input shaft 48 accommodates a boss 51 in a manner locked against rotation, which is used to receive the gear wheels 52 and 53 situated one above the other; coupled to the lower gear wheel 52 is the chain 35 which receives the trailing driving dogs 38, and coupled to the upper sprocket wheel 53 is the chain 34 which receives the leading driving dogs 37. The smaller gear 54 which is situated right at the top is permanently joined to the boss 51 with screws 55. If it is desired to alter the spacing between the driving dogs 37 and 38, the screws 55 are first of all loosened slightly. The ring 56 arranged between the smaller gear wheel 54 and gear wheel 53 now no longer wedges gear wheel 53 in the boss 51. A
pinion 57 mounted in gear wheel 53 is now able to roll off gear wheel 54, taking with it gear wheel 53 and consequently also the leading chain 34 with the driving dogs 37 associated therewith, and increases or decreases the distance between the driving dogs 37 and 38.

Claims

1. Machine for conveying a pre-folded packing box blank (8) in a packaging machine, the packing box blank (8) having a lid section (23) and a bottom section (22) and therebetween a first side wall section (24) and a second side wall section (26) on the side of the lid section (23) that is furthest from the first side wall section (24), the side wall sections (24, 26) also being folded in the same direction out of the plane of the lid section (23), with the following additional features:
- revolving conveyor devices are arranged in the region of the side wall sections (24, 26) in the conveying direction (4) of the packing box blank (8);
- the conveyor devices (34, 35) receive driving dogs (37, 38), with each pair of driving dogs (37, 38) looking one of the two side wall sections (24, 26) between them in the region of the end faces (30) of said side wall section (24, 26).

2. Machine according to claim 1, wherein the leading driving dog (37) in the conveying direction (4), and the trailing driving dog (38) in the conveying direction (4), of the pair of driving dogs (37, 38), are joined to different conveyor devices (34, 35).

3. Machine according to claim 1 or 2, wherein each conveyor device (34, 35) accommodates a plurality of driving dogs (37, 38).

4. Machine according to any of claims 1 to 3, wherein the respective trailing driving dog (38) in the conveying direction (4) is adapted to be positioned so as to locate the associated side wall section (24, 26) in the conveying direction (4).

5. Machine according to claim 4, wherein the positionable driving dog (38) is held pivotably in the conveyor device (35) and the driving dog (38) is moved along a stationary guide (45), more particularly a constraint, to position it.

6. Machine according to claim 5, wherein the positionable driving dog (38) is adapted to be pivoted between two limit stops (42, 43).

7. Machine according to any of claims 1 to 6, wherein the respective conveyor device (34, 35) is constructed as a revolving chain (34, 35), more particularly a horizontally revolving chain.

8. Machine according to any of claims 1 to 7, wherein the various conveyor devices (34, 35) are arranged one above the other and the driving dog(s) (34) of the upper conveyor device (37) are fastened with a downward orientation and the driving dog(s) (35) of the lower conveyor device (38) are fastened with an upward orientation, to the respective conveyor device (34, 35).

9. Machine according to any of claims 1 to 8, wherein the driving dogs (37, 38) are heel-shaped constructions, and the heels (39) of the leading and trailing driving dog (37, 38) of the respective pair of driving dogs (37, 38) are directed towards one another.

10. Machine according to any of claims 1 to 9, wherein the driving dogs (37, 38) extend for a height that is slightly less than the height of the side wall sections (24, 26).

11. Machine according to any of claims 1 to 10, wherein a device (54, 57) is provided for adjusting the conveyor device (34) of the leading driving dogs (37) relative to the conveyor device (35) of the trailing driving dogs (38).