Vertical form-, fill-, and sealing machine

Abstract

 The invention relates to a device for packaging products in foil material, comprising transport means for supplying a band of foil (4) material from a roll, a vertically disposed filling tube (1), which is provided with a feed funnel (2) on its inlet side, a guide element (3) mounted around the filling tube near the inlet side, which is provided with shoulder-like parts, over which the foil material can be passed in order to create an elongated container of foil material round the filling tube, first joining means (7) for joining the free longitudinal sides of the foil container, as well as second joining means disposed near the outlet side of the filling tube for forming a joint in a direction transversely to the longitudinal direction of the foil container.
The packaging machine according to the invention is characterized in that said first joining means form part of said transport means, which are partly in the form of a rotary drum.

Description

[0001] The invention relates to a device for packaging products in foil material, comprising transport means for supplying a band of foil material from a roll, a vertically disposed filling tube, which is provided with a feed funnel on its inlet side, a guide element mounted around the filling tube near the inlet side, which is provided with shoulder-like parts, over which the foil material can be passed in order to create an elongated container of foil material round the filling tube, first joining means for joining the free longitudinal sides of the foil container, as well as second joining means disposed near the outlet side of the filling tube for forming a joint in a direction transversely to the longitudinal direction of the foil container.

[0002] Generally, the manual packaging of large numbers of products in boxes or bags is a fairly inefficient process, and it is not a very suitable process, for hygienic reasons, when products intended for human consumption are to be packaged.

[0003] A packaging machine as referred to in the introduction makes it possible to package large numbers of products in a quick, efficient and hygienically sound and controlled manner in a substantially automated process.

[0004] All kinds of loose food products and non-food products (cookies or candies) are fed into the foil container that has been created round the filling tube via the feed funnel, which foil container has been sealed at its bottom side and in its longitudinal direction by the various joining means. After the foil container has been filled with a desired quantity (or number or weight) of products, the foil container is closed and sealed just above the products in order to obtain a foil package which is filled with cookies or candies.

[0005] With the current packaging machines, the longitudinal joint is formed in the foil material in one operation by the first joining means. The length of said joint is determined by the constructional dimensions of the first joining means.

[0006] The formation of a longer longitudinal joint for the purpose of obtaining a longer foil package requires additional operations, which thus slow down the process, viz. the sequential passing of additional foil material along a length equal to the standard length of the joint and the subsequent forming of the second joint by said first joining means. Consequently, such prior art packaging machines are only cost-effective when large amounts of products are to be packaged in a standardized foil package.

[0007] Such compound joints exhibit a number of drawbacks, since a) the foil material is weakened to a significant degree by the first joining means at the transition between two successive joints, or b) the successive joints do not properly join each other at said transition, resulting in a joint which does not seal the package completely.

[0008] In either situation a foil package comprising a faulty and possibly weak joint is obtained, which has a negative effect on the shelf life of products intended for consumption.

[0009] Furthermore, the length of each foil package is equal to that of one joint or to a multiple thereof: if it is desired to obtain foil packages having a different length with the prior art packaging machines, a setup change of the machines is necessary.

[0010] The object of the invention is to overcome the aforesaid drawbacks and to provide a packaging machine of the above kind by means of which foil packages of any length can be produced without setup changes or additional operations being required.

[0011] In order to accomplish that objective, the packaging machine is according to the invention characterized in that said first joining means form part of said transport means, which are partly in the form of a rotary drum

[0012] Now that the first joining means according to the invention form part of the transport means, the longitudinal joint can be formed simultaneously with the passing of the foil container. This makes it possible to create a foil package of (in theory) infinite length without successive process steps being required.

[0013] Now that the longitudinal joint is formed in the foil container in one operation by means of the device according to the invention, said joint does not exhibit the aforesaid drawbacks of a compound joint, viz. a weakened or not completely sealed transition between the successive joints.

[0014] In accordance with the invention, said first joining means are mounted on or in the surface of the transport drum in the longitudinal direction of the filling tube.

[0015] In another embodiment, which provides a compact device, the transport drum is positioned near the inlet side of the filling tube. Said transport drum can be mounted on a rotary shaft which lies in the horizontal plane.

[0016] In order to enable an optimum operation or control of the device according to the invention, said device is characterized in that it comprises a sensor which in use detects the presence or absence of the products in the foil container. In accordance with one embodiment, said sensor is a photocell, which is disposed near the outlet side of the filling tube.

[0017] In another compact embodiment of the device according to the invention, said second joining means are mounted on two carriers lying in the same horizontal plane on either side of the outlet side of the filling tube.

[0018] The second joining means can be moved towards each other for forming the transverse joints that are needed to obtain a foil package of any length.

[0019] A very compact device having a small 1 overall 1 dimension is obtained in particular in that said transport means and said carriers are jointly accommodated in one part of the housing of the device.

[0020] The device may furthermore comprise a compressor for driving the transport means and moving the second joining means relative to each other by means of a pressure medium.

[0021] One embodiment of the device is according to the invention characterized in that said first and/or said second joining means form the joints in the foil material by using heat or friction.

[0022] The invention will now be explained in more detail with reference to a drawing, wherein:

Figure 1 shows a packaging machine according to the prior art;

Figure 2 is a partial view of an embodiment of the packaging machine according to the invention; and

Figure 3 is a view of an embodiment of the packaging machine according to the invention.

[0023] In Figure 1, a prior art packaging machine is shown. Said packaging machine comprises a vertically disposed filling tube 1, on the inlet side of which a feed funnel 2 is present. Near the inlet side, a guide element 3 is fitted round the filling tube, which guide element includes shoulder-like parts 3a and 3b. A band of foil material 4 from a roll is passed over said shoulder-like parts 3a and 3b and subsequently led between filling tube 1 and guide element 3, so that an elongated container of foil material 4a is created around the filling tube. Said passing of the foil material 4 over guide element 3 takes place by transport means (6a, 6b), which are disposed on either side of the vertically disposed filling tube 1. Said transport means 6a, 6b can be placed in abutment with the filling tube 1 by well-known means, and they pass the foil material 4 that is present between the filling tube 1 and the transport means through the device. Guide rollers 5a and 5b serve to guide the foil material 4 in a smooth manner, and furthermore they create a desired pre-tension in the foil material.

[0024] First joining means 7 are disposed at the longitudinal free sides of the foil container 4a that has been created round the filing tube 1. Said first joining means 7 can likewise be placed in abutment with the filling tube 1 by well-known means, after which the free sides 4c and 4d of the foil material 4 that are present between the filling tube 1 and the joining means 7 are joined by means of friction or heat. In this manner a closed foil container 4a having a longitudinal joint 8 is created.

[0025] The prior art packaging machine furthermore comprises second joining means 9a and 9b, which are disposed on either side of the outlet side of filling tube 1. Said second joining means 9a and 9b can be moved towards and away from each other by suitable means. By moving second joining means 9a and 9b towards each other, the foil container 4a is pressed together between the two joining means, after which a transverse joint 10a can be formed in the pressed-together foil material by means of heat or friction.

[0026] As a result, the foil container 4a is closed from below, after which it can be filled with all kinds of products, for example cookies and candies, via feed funnel 2. Once the foil container has been filled with the desired quantity (or number or weight) of products, foil container 4a is moved the required distance by transport means 6a and 6b. Then the second joining means 9a and 9b form a second transverse joint 10b in the foil material just above the products that are present in foil container 4a, so that a foil package 4b is obtained.

[0027] Usually, a transverse joint 10a or 10b is so dimensioned that it can function as the lower joint for the next foil package 4b' at the same time. It is also possible for the second joining means 9a, 9b to form two parallel, closely spaced-apart transverse joints in the foil container 4a in one process step. Furthermore, the second joining means usually comprise cutting or perforating means (not shown), which cut the foil material through or perforate it after having formed the (single or double) joint 10b.

[0028] Thus the foil package 4b can be separated from the foil container 4a and be carried out of the packaging machine for further processing.

[0029] From Figure 1 it will be apparent that in the first instance the length of the transverse joint 8 depends on the constructional dimensions of the first joining means 7. In order to obtain a foil package 4a having a length greater than the constructional-dimensions of the joining means 7, the present first joining means 7 must be exchanged for another type, whose constructional dimensions correspond to the desired length of the joint 8. Not only does this setup change take time, during which the packaging machine is inoperative, but in addition it is necessary to keep a stock of several first joining means 7, each having a different length.

[0030] On the other hand it is possible to obtain a foil package 4b of considerably greater length by having said joining means 7 form successive joints 8 in the foil material. In order to realise this, the device must carry out additional operations, which slow down the process, viz. pass the foil container 4a through the transport means 6a, 6b over a distance which equals the standard length of the joint 8 (corresponding to the constructional dimensions of the first joining means 7), and subsequently form a next joint 8 by means of said first joining means 7.

[0031] This involves the risk of obtaining a faulty joint, however, because the foil material 4 is significantly weakened by the first joining means 7 at the transition between two successive joints 8, or because the successive joints do not correctly abut against each other, so that the joint that is formed does not provide a proper seal.

[0032] It will be apparent that a foil package 4b including a weak and incorrectly formed joint is not suitable for packaging products intended for consumption, because their shelf life cannot be guaranteed.

[0033] Figure 2 shows an embodiment of a packaging machine according to the invention. Parts that correspond to parts of Figure 1 are indicated by the same numerals. The packaging machine according to the invention likewise comprises a vertically disposed filling tube, which is provided with a feed funnel 2. Like the embodiment that is shown in Figure 1, the packaging machine according to the invention comprises a guide element 3 including shoulder-like parts 3a and 3b. A band of foil material 4 from a roll is passed over said shoulder-like parts 3a and 3b via a guide roller 5a so as to create a foil container 4a around filling tube 1, and that in such a manner that the longitudinal free sides 4c and 4d of the foil material 4 overlap.

[0034] The packaging machine also comprises transport means 6a, 6b, which are disposed on either side of the filling tube 1 and which pass the foil material 4 through the device and along the filling tube 1 in a similar manner as described in Figure 1. Said transport means are in the form of rotary transport drums 6a and 6b, which are mounted on rotary shafts 11a and 11b, respectively. Shaft 11a is movable in the horizontal plane, so that transport drum 6a can be moved towards and away from filling tube 1. In this embodiment, unlike the embodiment that is shown in Figure 1, transport 6a abuts against filling tube 1, where the long sides 4c and 4c of the foil container 4a being formed overlap.

[0035] In accordance with the invention, said first joining means 7 form part of the transport drum 6a. In particular, said first joining means 7 are mounted on or in the surface of the transport drum 6a, and that in such a manner that they join the overlapping long sides 4c and 4d of the foil material by means of heat or friction upon rotation of transport drum 6a. The joining means 7 are oriented in the longitudinal direction of the filling tube 1 or foil container 4a, therefore.

[0036] Unlike the prior art packaging machine (see Figure 1), which can only form a joint 8 of limited length in the foil material, the packaging machine according to the invention is capable of forming a foil container 4a having a longitudinal joint 8 of infinite (in theory) length. Said joint 8 is formed while the foil material 4 is being passed through the machine, and it is not made up of successive joints, as is the case in Figure 1. The packaging machine according to the invention is capable of forming a homogeneous joint whilst avoiding the drawbacks of a compound joint 8 as described above.

[0037] First joining means 7 can be activated independently of the transport means 6a, 6b, so that it is also possible to pass the foil container through the device without forming a joint 8.

[0038] The packaging machine according to the invention also comprises second joining means 9a and 9b for forming transverse joints 10a and 10b in foil container 4a. Said second joining means 10a and 10b are mounted on carriers 12a and 12b, respectively, which lie in the same horizontal plane on either side of the outlet side of the filling tube 1. Said carriers and said second joining means can be moved towards and away from each other in order to press the foil container 4a together and form a transverse joint 10a or 10b by means of heat or friction.

[0039] Now that it is possible with the packaging machine according to the invention to produce a foil package 4b of any length, standstill of the packaging machine and setup changes to a different type of first joining means 7 are things of the past. The filling of the foil package 4b with products supplied via the feed funnel (in the direction indicated by the arrow), such as cookies and candies, can take place while the foil material 4 is being passed through and the longitudinal joint 8 is formed simultaneously therewith. By furthermore moving the transport drum 6a and the first joining means 7 mounted thereon to a position close to the inlet side of filling tube 1, the length of the filling tube can be considerably reduced, which means a significant gain especially as regards the overall vertical height.

[0040] The shorter filling tube 1 furthermore enables a reduction of the height of fall of the products to be packaged, which is highly desirable in the case of fragile products, such as cookies.

[0041] As the figure shows, the drive shafts 11a and 11b of the transport drums 6a and 6b, respectively, as well as the carriers 12a and 12b of the second joining means 9a and 9b are jointly accommodated in a part 13 of housing 18 of the packaging machine. Since the above parts and the parts to be driven are accommodated on one side of the housing 18, a considerable gain as regards the overall dimension is obtained in horizontal direction as well. As a result of this construction, the device is readily accessible from one side, which makes it easy to carry out maintenance work.

[0042] The packaging machine furthermore comprises a compressor 15 (not shown) for driving the shafts 11a, 11b and the respective carriers 12a and 12b that are accommodated in housing part 13 by means of a pressure medium, for example compressed air. Since the packaging machine according to the invention can be connected to a 220 V power source, the packaging machine is easy to transport and to install, owing to its small horizontal and vertical overall dimensions, whilst the user is not required to provide any specific power sources, such as high-voltage current or a system of compressed air lines.

[0043] Joining means 7 and 9a, 9b are energized by the control means via suitable connection leads.

[0044] If desired, the control of the packaging machine, for example PLC control, can be programmed or adjusted in a simple manner by means of a suitable input panel 14. It is possible to adjust a desired length of the foil package 4b via said input panel 14, or, depending on the type of foil material 4, to set the operating temperature of the various joining means 7, 9a and 9b.

[0045] Since the transport means 6a, 6b pass the foil material 4 through the device at a constant speed, the length of the foil material 4 being passed through can be easily determined on the basis of the time that has passed, and subsequently be compared with the desired length that has been set via the input panel. On the basis of this comparison, the second joining means 9a and 9b will be excited at the right moment by the control means so as to form transverse joint 10b.

[0046] A more flexible use of the packaging machine, wherein the packaging machine is not driven on the basis of a pre-set package length, can be obtained by using a sensor or photocell 17 disposed near the outlet side of filling tube 1, which detects the presence of the products that are present in the foil package 4b. The moment the foil container 4a contains a predetermined quantity (or number or weight) of products and the sensor 17 no longer detects any products, the transport means 6a, 6b will be driven by the sensor, via the control means, to move the foil container 4a a specific distance yet (whilst the longitudinal joint 8 is formed by the first joining means 7 simultaneously therewith), after which the second joining means 9a, 9b will be activated.

[0047] Thus the length of the foil package 4b is directly determined by the quantity of products to be packaged, and premature sealing of the foil package 4b is prevented.

[0048] If desired, the filling tube 1 may be provided with two diverging spreader pins 1a and 1b at its outlet side. Said pins keep the closed foil container 4a open, so that said container is easier to fill with the products to be packaged, which products are being supplied via the feed funnel 2. Optionally, an outlet element 1c can be used, which can be fitted round the free end of filling tube 1.

[0049] The drive shafts 11a and 1b can likewise be moved towards and away from each other, in order to make it easier to introduce a new band of foil material 4 by hand, for example. The two transport drums 6a and 6b come into contact with the filing tube 1 repeatedly, therefore. The feed funnel 2 is provided with a stiffening 2 in order to be capable of absorbing the forces that are thus set up in filling tube 1.

[0050] The packaging machine according to the invention is very suitable for creating so-called cushion-like foil packages B of any bag length. Optionally, the packaging machine may be fitted with pins 19 to be driven by the control means, which can be moved towards each other the moment a transverse joint 10a or 10b is being formed by second joining means 9a and 9b. As a result, the foil material 4 is folded at the joint 10a (10b), so that a so-called block bag rather than a cushion-like bag is formed.

[0051] Furthermore the packaging machine can be operated by means of a foot switch 16 by operating staff.

Claims

1. A device for packaging products in foil material, comprising

transport means for supplying a band of foil material from a roll,

a vertically disposed filling tube, which is provided with a feed funnel on its inlet side,

a guide element mounted around the filling tube near the inlet side, which is provided with shoulder-like parts, over which the foil material can be passed in order to create an elongated container of foil material round the filling tube,

first joining means for joining the free longitudinal sides of the foil container,

as well as second joining means disposed near the outlet side of the filling tube for forming a joint in a direction transversely to the longitudinal direction of the foil container, characterized in that said first joining means form part of said transport means, which are partly in the form of a rotary drum.

2. A device according to claim 1, characterized in that said first joining means are mounted on or in the surface of the transport drum in the longitudinal direction of the filling tube.

3. A device according to any one or more of the preceding claims, characterized in that the transport drum is positioned near the inlet side of the filling tube, at the location of the longitudinal sides of the foil package.

4. A device according to any one or more of the preceding claims, characterized in that said transport drum is mounted on a rotary shaft which lies in the horizontal plane.

5. A device according to any one or more of the preceding claims, characterized in that said device comprises a sensor which in use detects the presence or absence of the products in the foil container.

6. A device according to claim 5, characterized in that said sensor is a photocell, which is disposed near the outlet side of the filling tube.

7. A device according to any one or more of the preceding claims, characterized in that said second joining means are mounted on two carriers lying in the same horizontal plane on either side of the outlet side of the filling tube.

8. A device according to claim 7, characterized in that said second joining means can be moved towards each other

9. A device according to any one or more of the preceding claims, characterized in that said transport means and said carriers are jointly accommodated in one part of the housing of the device.

10. A device according to claim 9, characterized in that said device furthermore comprises a compressor for driving the transport means and moving the second joining means relative to each other by means of a pressure medium.

11. A device according to any one or more of the preceding claims, characterized in that said first and/or said second joining means form the joints in the foil material by using heat or friction.

Drawing