GB2374333A

GB2374333A - Packaging apparatus and method

Info

Publication number: GB2374333A
Application number: GB0216855A
Authority: GB
Inventors: Jacob Brinkman
Original assignee: Cryovac LLC
Current assignee: Cryovac LLC
Priority date: 1998-02-27
Filing date: 1999-03-01
Publication date: 2002-10-16
Anticipated expiration: 2019-03-01
Also published as: GB0216855D0; GB2374333B

Abstract

A method of filling a bag, e.g. with cheese, comprises providing a double plane support device 10 having first and second plane support surfaces 101, 102 inclined relative to each other such that a bag can be supported by both surfaces when the planes are suitably inclined, and mounting the device such that an intersection of the planes is at a predetermined position relative to a conveying path; tilting the device such that the first surface is horizontal; displacing product horizontally into a horizontal bag; placing the loaded bag onto the first surface; tilting the device such that the bag slides on the first surface to rest against the second surface, the bag becoming upright; weighing the bag to determine extra product needed to achieve a target weight; adding extra product and closing the bag. A further double plane support device 16 may be provided to return the closed bag to the horizontal. Also claimed is a packaging apparatus comprising the double plane support device.

Description

PACKAGING APPARATUS AND METHOD TECHNICAL FIELD OF THE INVENTION The present invention relates to packaging apparatus, and in particular to packaging apparatus for packaging in plastics bags. semi rigid blocks of product such as cheese.

BACKGROUND ART Conventional packaging apparatus for such applications generally involve one or more towers in which a product is collected ready for packaging, and an ejection apparatus at the base end of each tower for ejecting the product in predetermined lengths from a horizontally aligned outlet thereof onto a horizontal support device. The ejection apparatus generally has a square or rectangular shaped outlet, and is provided with a device for gripping a bag when fitted over the outlet In operation, the inlet portion of a bag which is generally made of an impervious material such as plastics, is manually fitted over the outlet and the gripping device then operated to hold the bag in place. The ejection apparatus is then operated to eject a length of the product into the bag, which is cut off by a cutter at a predetermined size, and the gripping device released. to allow the filled bag to be pushed by an ejector of the ejection apparatus onto the support device.

Since the operation of fitting the bag to the outlet of the ejection apparatus, is carried out manually, the operation 1$ time consuming, contaminant can be introduced to the product, and space is required to allow the operator access to the region.

The support device is generally in the form of a conveyor belt which then conveys the filled bag to a weighing apparatus where the bag is weighed. If the weight is below a predetermined weight then the bag must be topped up with additional product. Since this is done manually and generally requires turning the bag to an upright condition with the opening at the top, the operation is time consunung and contaminants can be introduced to the product. (Incidentally a continual problem here is that human operators develop occupational overuse syndrome in their wrists from the activity). To minimise this requirement, the bags are generally over filled, thus providmg more product than necessary with a loss of profit.

Once the bag has been weighed, the top of the bag is folded to form gussets ready for sealing under vacuum, or alternatively a"pillowcase seal"is prepared by a process involving stretching part of the neck of the bag. This also is done manually, and is thus time consuming and can introduce contaminant to the product. Moreover, there is the possibility of finger contamination of the surface of the inlet portion of the bag, which can cause defective sealing by the subsequent sealing apparatus. Furthermore, the manual operation results in a lack of uniformity of the surfaces which can result in wrinkles, again affecting the subsequent sealing operation. Moreover, the bag must be accurately positioned by hand on the conveyor so that the inlet portion is lined up with sealing bars of the subsequent vacuum sealing apparatus OBJECT OF THE INVENTION It is an object of the present invention to provide a packaging apparatus which addresses the above problems with conventional apparatus, or at least provides the public with a useful choice DISCLOSURE OF THE INVENTION According to a first aspect of the present invention there is provided a method of filling a bag, comprising the steps of ; providing a double plane support device comprising a first plane support surface and a second plane support surface inclined and positioned relative to each other such that a bag to be positioned can be supported by both of the support surfaces when the planes are tilted as one to a predetermined inclination, and mounting the double plane support device such that in a final condition an intersection of the first and second planes is at a predetermined position with respect to the conveying path; tilting the double plane support device such that the first plane support surface is substantially horizontal; loading a bag by displacing product horizontally into the bag while the bag is horizontal; placing the thus loaded bag onto the first plane support surface;

'Itin, tilting the double plane support device to a final condition such that the bag t slides on the first plane support surface to rest against the second plane support

surface, whereby the bag becomes upright; weighing the loaded bag to predetermine a top-up charge of product to achieve a target weight of the filled bag; adding the predetermined top-up charge to the loaded bag; and closing the thus filled bag.

In another aspect the invention can broadly be said to consist of a packaging

apparatus adapted for packaging a product which is moved substantially horizontally apparatus adapted for packa,- into a bag, said packaging apparatus comprising :- a bag filling apparatus including a bag supply means, means for supplying a bag from the bag supply means, means for holding an inlet region of the bag open to receive said product, and means for advancing a product substantially horizontally into the bag; positioning apparatus in the form of a double plane support device comprising a first plane support surface and a second plane support surface aligned substantially perpendicular to each other, the support surfaces having a device for supporting a product resting thereon and moving or allowing movement of the product in a longitudinal direction mutually parallel to the planes, and a mounting device for supporting the double plane support device so as to be movable between a first position wherein the first plane support surface is substantially horizontal, and a second position wherein the second plane support surface is substantially horizontal ; means for advancing the bag with product therein from said bag filling apparatus to said positioning apparatus; bag weighing apparatus for weighing the bag loaded with product therein, and supplementary filling apparatus responsive to said bag weighing apparatus and capable of filling additional product into a bag subsequent to its having been loaded and placed upright by said positioning apparatus.

Further aspects of the present invention will become apparent from the following description given in conjunction with the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a plan view of the essential features of a packaging apparatus according to an embodiment of the present invention; Fig. 2A is a side view on A-A of Fig. 1, showing details of a bag fitting apparatus;

Fig. 2B is an end view of Fig. 2A, showing details of the bag fitting apparatus and Z ! l t : l ZD the arrangement of a second conveying line ; Fig. 3 is a schematic diagram of an alternative arrangement for a bag supply device, Fig. 4 is a side and end view of a bag lifting unit; and Fig. 5 is a plan, end and side view of a support device.

BEST MODE FOR CARRYING OUT THE INVENTION Fig. lIS a plan view of the essential features of a packaging apparatus according to an embodiment of the present invention generally indicated by arrow 1, for packaging in plastics bags, semi-rigid blocks of product such as cheese The packaging apparatus 1 of this embodiment comprises two conveyor paths (see Fig. 2B) each having five towers 2 (only two shown in the Figure), in which the product is collected ready for packaging, and an ejection apparatus 4 at the base end of each tower 2 for ejecting the product in predetermined lengths

from a horizontally aligned rectangular outlet 6 onto a horizontal support device in the form of a conveying table 8. The conveying table 8 is additionally provided with transverse conveying rollers generally indicated by arrow 9 (FIG. 2B) in the vicinity of the outlet 6 to facilitate pushing a filled bag onto the conveying table 8 by an ejector of the ejection apparatus 4.

A feature of the packaging apparatus I is a bag fitting apparatus generally indicated by arrow 7 for fitting an inlet region of -8 bag over an outer peripheral surface of the outlet 6. The bag fitting apparatus is mounted on upper and lower tracks 9a, 9b (FIG. 2A) so as to be movable between the respective ejection apparatus 4, for presenting bags thereto.

With this embodiment, the bag fitting apparatus is supplied from a bag supply apparatus generally indicate by arrow 70, wherein bags are stored in a stack on top of each other.

The packaging apparatus I also comprises a positioning apparatus in the form of a block erector 10 generally indicated by arrow J 0 for tilting a bag which has been filled with product by the ejection apparatus 4 into an upright condition.

Furthermore there is provided a supplementary filling apparatus in the form of a check weigher and top up apparatus generally indicated by arrow 12 for checking the weight of the filled bag, and topping up with additional product if the weight is less than a specified weight.

Moreover, there is provided a folding apparatus in the form of a bag stretcher and spot sealing apparatus generally indicate by arrow 14 for folding an inlet to a bag which has been filled and

topped up with product by the check weigher and top up apparatus 12, into a suitable form for subsequent sealing.

After the bag stretcher and spot sealing apparatus 14, there is provided another positioning apparatus in the form of a block erector 16 similar to the block erector 10, for turning the filled bag back onto its side, and accurately positioning the filled bag relative to the conveying path leading to a collating apparatus 1 S and then on to a vacuum sealing apparatus 20.

The vacuum sealing apparatus 20 is a conventional vacuum sealing apparatus having a rail along which the folded opening of the bag slides, which leads to a heat sealing device inside a vacuum chamber. Once the chamber has been evacuated to predetermined conditions, thereby drawing

air out of the spot sealed (partially sealed) bag, the inlet to the bag is sealed by the heat scaling device, thus completing the packaging operation.

Instead of the sealing apparatus 20, a suitable sealing apparatus as described later, may be provided at the bag stretching and spot sealing apparatus 14.

A feature of the packaging apparatus 1 according to the invention is that all operations are automated. Hence problems inherent with conventional apparatus involving manual operation are eliminated. For example, since there is no longer the need to provide access to various sections, a more compact arrangement is possible. With the packaging apparatus 1 of the present invention, an arrangement with two conveyor paths close together as shown in FIG. 2B thus becomes possible, FIG. 2A and 2B show details of the bag fitting apparatus 7. This bag fitting apparatus is supplied with bags from the bag supply apparatus 70 as mentioned before, which comprises a bag storage magazine 72 for storing a predetermined number of preformed bags in a stack on top of each other in a flattened condition. The bag fitting apparatus 7 comprises a bag opening device 74 for opening an inlet to a bag on the top of the stack, a bag gripping device 76 for releasably gripping the bag at an inlet portion of the bag, and an actuating unit 78 for moving the gripping device 76 between an upper position where a bag opened by the bag opening device 74 can be releasably gripped by the gripping device 76 (the upper left position in FIG. 2B), and a position where the inlet portion of a bag being gripped by the gripping device 76 is positioned over the outer peripheral surface of the outlet 6 (the lower right position in FIG. 2B).

As mentioned above, the bag supply apparatus 70 comprises a bag storage magazine 72 containing a number of preformed bags, stored in a stack on top of each other in a flattened condition. nife magazine is generally referred to as a "cassette".

Ideally. the orientation of the bags positioned in the stack will be such that the bag inlet of each bag will face towards the bag opening device 74, with the sealed end of each bag facing away from the bag opening device 74 towards the rear of the bag fitting apparatus 7.

Ideally, the operation of the bag supply apparatus 70 should be such that when in use the stack's uppermost bag (which can be called the"active"bag for ease of reference) can be easily and efficiently separated from the balance of the stack, in particular from the bag immediately below

it (which can be called the"passive"bag for ease of reference), and presented in the appropriate state for opening by the bag opening device 74.

There can be some electrostatic cling present between the bags in the stack, and this can cause fouling of the bag supply apparatus 70 if more than one bag is lifted from the stack during the process of presenting a bag to the bag opening device 74.

As shown by FIG. 4, a bag lifting unit 301 is provided at the rear of the bag storage magazine 72. The bag lifting unit 301 comprises a lifting member 302 provided above the stack in a first position, positioned above the sealed end of the active bag.

Lifting each bag from its sealed end is preferred as this reduces the number of creases and folds occurring in the walls of the bag, which can detract from the efficiency of the process of presenting a bag to the bag opening device 74. That is, because a bag will have a greater structural rigidity at or close to its sealed end, the walls of the bag are less likely to crease or fold in many places when the bag is lifted from its sealed end. Lifting a bag from its open end is likely to generate a number of creases or folds, which can interfere with the efficiency of the bag opening process. If the bag is lifted from its sealed end, the lifting process should generate fewer folds or creases in the walls of the bag than if the bag were lifted from its open end.

As can be seen from FIG. 4, the lifting member 302 is equipped with vacuum operated suction cups on a lower surface thereof for attaching the lifting member 302 to the outer surface of a bag, relative to the sealed end of the bag.

The lifting member 302 is capable of movement towards the stack into a second position wherein the suction cups are brought into close proximity to the stack, at which time the suction cups are brought into contact with the exposed surface of the sealed end of the active bag as aforementioned and as seen at 303. Once the suction cups are activated, the suction cups are lifted at an angle away from the surface of the active bag, in doing so taking the sealed end of the active bag with them. This action of attaching the suction cups to the sealed end of the active bag and then moving rhe suction cups away from the stack separates the sealed end of the active bag from the sealed end of the bag immediately beneath it in the stack, the passive bag.

In moving the suction cups in this way, a gap 304 is created between the underneath surface of the sealed end of the active bag and the upper surface of the sealed end of the passive bag, which has remained on the stack in a flattened position.

The weight of the sealed end of each bag should be enough to overcome any electrostatic forces present at the sealed end of the bags such that it is not necessary to provide restraining means to

hold the sealed end of the passive bag down whilst the sealed end of the active bag is lifted away from the stack. However, if need be, restraining means can be provided which ensures the passive bag, in particular the sealed end of the passive bag, and any bags immediately beneath it, are not lifted simultaneously away from the stack with the active bag.

To ensure only one bag is lifted from the stack at a time and presented for opening by the bag opening device 74. a support device is positioned relative to the lifting member 302 towards the rear of the bag storage magazine 72, and in close proximity to the top of the stack. The purpose of the support device is to provide a separating action, effectively"unpeeling"the active bag from the rest of the stack, particularly from the passive bag which is to form the top of the stack below once the active bag is removed.

As shown in FIG. 5, the support device generally shown at 305 comprises a main housing 306 which contains an extendible member 307, extendible in the direction of the arrow towards the bag opening device 74. The extension (and subsequent retraction) of the extendible member 307 can be achieved either by pneumatic or hydraulic means. In the example shown in FIG. 5, the extendible member 307 can comprise a rigid front frame 308 attached to a movable arm 309.

A number of extendible and retractable tapes 310 can be provided, one end of each tape being connected to the rigid front frame 308 of the support device. The other end of each tape can be held in the main housing 306 of the support device, with suitable means being provided to allow each tape to extend and retract with the extension and retraction of the extendible member 307.

Alternatively the support device's extendible member 307 can comprise a solid sheet of rigid material.

Once the gap is formed as aforementioned between the sealed ends of the active and passive bags, the extendible member 307 is then extended from the support device in the direction of the bag opening device 74, and in doing so the extendible member 307 is slid under the active bag.

As the extendible member is extended, the aforementioned tapes 310 are unravelled, thereby providing a support surface for the active bag to rest upon once it is separated from the stack.

During the extension of the extendible member, the rigid front frame 308 acts as a''plough", peeling the active bag from the top of the stack and separating the active bag from the passive bag. Once the extendible member is fully extended towards the bag opening device 74, the active bag is now completely separated from the top of the stack. During the separation of the active bag from the rest of the stack, and in particular the passive bag, the sucions cups of the lifting member retain their grip on the sealed end of the active bag.

Once the active bag is separated from the stack, it is then positioned for engagement with the bag opening device 74.

It is desirable to ensure the positioning of the bag for presentation to the bag opening device 74 is as accurate as possible. Therefore, after the active bag has been separated from the stack it is acted upon by bag positioning means (not shown) which"shuffles"the bag from side to side such that the bag is brought into an abutting relationship with at least one strategically placed positioning guide. thereby locating the active bag in the exact position for engagement by the bag opening device 74. The"shuRling"action can be achieved by using a plate member positioned alongside the active bag which pushes the bag towards the aforementioned positioning guide (s). As the suction cups still retain a grip on the sealed end of the active bag, the lifting member can also be used to assist in the correct positioning of the active bag for engagement by the bag opening device 74.

The bag opening device 74 comprises a lifting member 80 (opening member) provided with vacuum operated suction cups on a lower surface thereof for attaching the lifting member 80 to an outer surface of the bag, a bottom wall holding device 82 provided with vacuum operated suction cups (not shown in the figure) for holding a bottom wall of the bag when positioned thereover, and a positioning mechanism (not shown in the figures) for moving the lifting member 80. The positioning mechanism moves the lifting member 80 between a first position (shown in full lines in FIG. 2B) wherein a bag can be attached to the lifting member 80 by the suction cups, a second position (shown in dotted lines directly above the first position) wherein an upper wall of a bag attached by the suction cups is lifted to thereby open the bag inlet and lift

the bag from the stack, a third position (shown in dotted lines to the left of and at a lower level than the second position) displaced horizontally from the second position such that a bag attached to the lifting member 80 is moved horizontally to a bottom wall attachment position, and a fourth position (shown in dotted lines above the third position) wherein the inlet of a bag which is being held by the bottom wail holding device 82 is further opened.

As shown in FIGS 2B, the bag gripping device 76 comprises two vertically aligned parallel plates 84 supported in spaced apart relation to each other by respective arms 86 which are attached to opposite ends of axially aligned shafts 88 of the actuating unit 78. The actuating unit 78 comprises a mounting unit (only partially visible in FIG. 2B) for mounting the shafts 88 so as to be movable apart axially. so as to be rotatable about a longitudinal axis thereof and so as to be movable in a substantially horizontal plane.

In gripping the bag with the bag gripping device 76, the actuating unit 78 moves the arms 86 relative to each other between a first separation distance at which the plates 84 can be fitted inside a bag inlet, and a second wider separation distance at which the plates 84 press against and grip the opposite vertically aligned sides of the bag inlet. With this arrangement, when the upper and lower inlet portions of the bag are being held by the suction cups of the lifting member 80 and the bottom wall holding device 82, the force due to the action of separating the arms 86 to grip the bag, can be made sufficient to separate the upper and lower inlet portions of the bag from the suction cups irrespective of whether or not suction is released from the suction cups.

When moving the gripping device 76 between the beforementioned upper left and lower right positions, the mounting shafts 88 together with the arms 86 of the gripping device 76 are turned while being moved in the horizontal plane, as shown by the successive positions in FIG. 2B, thereby moving a bag held by the gripping device 76 from the magazine stack to position the inlet portion of the bag over the outer peripheral surface of the outlet 6. Once positioned at the outlet 6, the mounting shafts 88 are rotated about their longitudinal axes so as to separate the plates 84, from the inside surfaces of the bag, and the arms are then moved apart away from the vicinity of the outlet 6.

The support device is not retracted back towards main housing 306 until the active bag has been removed by the bag opening device 74 from the bag supply apparatus 70. Whilst the inlet of the bag is being acted upon by the vertically aligned plates 84 of the bag gripping device 76, the suction cups of Lifting member 302 retain their grip upon the sealed end of the bag during the opening process. Once the inlet of the bag has been opened as required, the suction cups of lifting member 302 are disengaged to allow the bag to be removed from the bag supply apparatus by arms 86.

In the above description, moving the arms 86 together and apart for the gripping operation, has been achieved by moving the shafts 88 axially relative to each other. However any suitable device may be used for achieving this movement. For example the arms 86 may be pivotally mounted on a single shaft so as to be pivotal relative thereto.

The block erector 10 as shown in FIG. 1 IS a double plane support device compnsmg a first plane support surface 101 and a second plane support surface 102 aligned substantially

perpendicular to each other. The support surfaces 101, 102 are in the form of conveyor tables so that a product resting thereon can be moved along the conveying path. That is in a longitudinal direction mutually parallel to the planes of the support surfaces. While not shown in FIG. 1, the block erector 10 is mounted so as to be movable between a first position (as shown in FIG. 1) where the first plane support surface 101 is substantially horizontal, and is aligned with a surface of the horizontal support device 8, and a second position wherein the second plane support surface 102 is substantially horizontal, and is aligned with a subsequent horizontal support surface of the check weigher and top up apparatus 12. This movement is provided by a vertical actuator 103. The mounting may involve a linkage device and/or guide tracks to enable accurate movement of the block erector 10 between the two positions.

In operation a bag lying horizontally on the surface of the horizontal support device 8 after being filled by the ejection apparatus 4, can be tilted through 90 degrees by the block erector 10 to bring the bag into an upright condition with the inlet portion facing upwards. Moreover, during the tilting operation the bag will slide sideways on the first plane support surface 101 to rest against the second plane support surface 102, thus accurately aligning the bag with a predetermined path along the conveying path.

The check weigher and top up apparatus 12 comprises weighing table 121 and a discharge device in the form of a horizontally aligned auger unit 122 mounted over the weighing table 121. The auger unit 122 discharges a product contained in a hopper 124, downwards into an inlet of a bag positioned on the weighing table 121. The auger is designed so that during the topping up operation, the product discharged therefrom is spread evenly over the top of the product in the bag. Preferably this is achieved by moving the auger unit 122 relative to the bag inlet, thereby minimising any effect on the weighing operation. However depending on the measuring instrumentation it may also be possible to move the bag on the weighing table 121 relative to the auger unit 122. Control of the check weigher and top up apparatus 12 is by means of a computer, which ensures that the bag is accurately topped up with product to a predetermined weight, and the product is spread evenly, to facilitate the subsequent folding and

sealing of the bag inlet.

0

The bag stretcher and spot sealing apparatus 14 comprises a table 141 and a folding device comprising six fingers (not shown in the figure) mounted relative to a base member 142 which is supported over the table 141, and a finger actuating unit 144 for inserting four of the fingers into an inlet of the bag, and positioning two of the fingers outside the bag so as to appropriately fold the side walls of the bag relative to each other to form a folded inlet gusset suitable for sealing by the vacuum sealing apparatus 20. The bag stretcher and spot sealing apparatus 14 also comprises a spot sealer for providing a tack weld to the folded inlet of the bag so as to prevent unfolding. This ensures that the folded portion is reliably held in the folded condition while the bag is being conveyed to the subsequent vacuum sealing apparatus 20.

In order to accurately carry out the sealing and spot welding operation and make a neat gusset fold to ensure a good seal, the bag must be accurately positioned on the table 141. With the present embodiment, this IS automatically achieved by the upstream block erector 10.

As mentioned before, instead of having a separate vacuum sealing apparatus 20, this may be combined with the bag stretcher and spot sealing apparatus 14. Such a vacuum sealing apparatus may comprise a passage formed inside at least one of the fingers, a device for removing gas from the bag via the passage, and a sealing device for sealing the bag once gas has been removed.

The block erector 16 downstream of the bag stretcher and spot sealing apparatus 14 is the same as the block erector 10, and hence similar components are denoted by the same symbol and description is herein omitted.

Again since the bag is accurately positioned by the block erector 16, then problems such as defective sealing in the subsequent vacuum sealing apparatus 20 due to inaccurate positioning inherent with a manual positioning operation, can be eliminated.

In operation of the packaging apparatus of the embodiment, the bag fitting apparatus 7 is operated to remove a bag from the magazine stack 72 and fit an inlet region of the bag over an outer peripheral surface of the outlet 6 of the ejection apparatus 4. Once the bag is fitted, the ejection apparatus 4 is operated to eject a predetermined length of cheese (of slightly less weight than a specified final weight) from the outlet 6 into the bag, and then push the filled bag onto the

conveying table 8. The filled bag of cheese is then conveyed to the block erector 10 where it is tilted to an upright condition and accurately aligned with the conveying path by means of the second plane support surface 102. The second plane support surface 102 which is a driven conveyor then transports the bag onto the check weigher and top up apparatus 12 where it is weighed while being topped up to a final specified weight by the auger unit 122. The bag is then transferred off the weighing table 121 of the check weigher and top up apparatus 12 by means of a conveying band thereon, and onto the bag stretcher and spot sealing apparatus 14.

The inlet of the bag is then folded and gusseted by the fingers of the folding device, and the folded inlet then tack welded to keep the folded condition.

The bag is then transported to the second block erector 16 where it is tilted back to lie on its side, and is also accurately aligned with the conveying path, so that the folded inlet is correctly positioned ready for being guided by the rail leading to the vacuum sealing apparatus 20.

The bag is then conveyed onto the collator 18 where the bags are collated and then conveyed to the vacuum sealing apparatus 20, where they are subjected to a vacuum to remove air, and the folded inlets then heat sealed.

FIG. 3 shows an alternative type of bag supply apparatus generally indicated by arrow 200. This apparatus may be preferable to the bag supply apparatus 70 in the case where bags of acceptable standard can be supplied in roll form. In FIG. 3 components the same as in the previous figures are denoted by the same symbols and description is omitted.

With this apparatus 200, bag material or preformed bags are stored in a roll 202. The bag material may be a simple flat tube of packaging material which is formed with gussets. In this case there is the requirement for a heat sealer to heat seal the gusset region, a cutter to cut off the bag, and a subsequent heat sealer to seal the bottom of the bag. Alternatively the bag material may be a roll of pre-gusseted bags with perforations between each bag. In the latter case there is no need for the gusset heat sealer, cutter and bottom heat sealer, the preformed bags being simply tom from the roll as required.

The apparatus in FIG. 3 is designed for the former type of bag material.

The bag material is fed from the roll 202 by means of feed rollers 204 and a tensioner 206 provided with a gusset sealer 208, to a cutter and head sealer 210 where the bag end is sealed

and then cut into predetermined lengths by a cutter. It then falls under gravity to the bag fitting apparatus generally indicated by 212.

The bag fitting apparatus 212 for use with such a bag supply apparatus 200, comprises a bag opening device 214 for opening an inlet to a bag (indicated by X) supplied from the bag supply device 200. a bag gripping device 216 for releasably gripping an inlet portion of the bag X opened by the bag opening device 214, and an actuating unit 218 for moving the bag gripping device 216 between an upper position where an inlet portion of the bag X is gripped on both sides by arms of the gripping device 216 and a lower position where the inlet portion of the bag

X being gripped by the gripping device 216 is positioned over an outer peripheral surface of an =fip outlet 6.

The bag opening device 214 comprises two opening member 214a, 214b provided with suction cups 215 for attaching the opening members 214a, 214b to outer surfaces of the bag X, and a positioning device for moving the opening members 214a, 214b between a first position (close together position) wherein the bag X can be attached to the opening members 214a, 214b by the suction cups 215, and a second position (apart position) wherein opposite walls of the bag are moved apart to thereby open the bag inlet.

A bag gripping device 220 comprises two members 221a, 22tb (only 221a visible in FIG. 3) supported in spaced apart relation by respective arms (not shown) so as to be movable relative to

each other between a first separation distance at which they can be inserted into the bag inlet, tv and a greater second separation distance wherein they grip against the sides of the bag.

The two members 221 a, 221 b are mounted on the bag gripping device 220 so as to be rotatable about their longitudinal axis when an inlet portion of a bag being gripped thereby is positioned over the outer peripheral surface of the outlet 6. The actuating unit and its operation is similar to that of the first embodiment and will not be described further here.

In operation of the packaging apparatus of FIG. 3 fitted with the roll type bag supply apparatus 200. the feed rollers and tenstoner are operated so that bag matenal is pulled off the roll to a predetermined length, and then gusseted and cut ready for supply to the bag fitting apparatus. In this operation the tensioner is moved to maintain tension on the roll and to allow for the stop- start feed required to enable heat sealing and cutting of the bag material.

While the present invention has been described in relation to the stack type bag supply apparatus and the roll type apparatus of FIG. 3. the invention is not limited to this. For example depending on requirements, the roll type bag supply apparatus could be modified so as to supply bags to the stack position of the first embodiment, that is to say so that bags were supplied horizontally therefrom.

In the above, the arrangement of the packaging apparatus has involved two conveyor paths each having five rowers. This conforms to a conventional packaging apparatus to which the respective apparatus of the present invention arc to be fitted. However, the invention is not limited to such an arrangement, and any number of towers may be provided on one or two conveying paths. Moreover, the advantages provided by the invention may result in the complete redesign of packaging apparatus so as to have a large number of towers with several bag fitting apparatus moving along the conveyor path to present the bags for filling.

Furthermore, the packaging apparatus has been described above as a packaging apparatus for packaging blocks of cheese. However, the apparatus is not to be limited to this application and can be applied to the packaging of other products especially where contamination due to human contact is a problem.

Furthermore the respective components of the packaging apparatus have been described in relation to being fitted to the packaging apparatus. However, these may also be used individually in other applications where their features may provide an advantage. For example the positioning apparatus may find application in assembly lines where an article must be accurately aligned on a conveying path.

We believe the advantages of the invention to be as follows, however it should be appreciated that the following list is given by way of example only.

1. By providing a bag fitting apparatus for the packaging apparatus, then problems inherent with manual operation such as being time consuming, risk of contamination of the product, and requiring space to allow the operator access to the region can be eliminated.

2. By providing the supplementary filling apparatus, the filling operation can be carried out effortlessly and accurately for each bag, and hence the bags can initiaUy be slightly under filled

by the ejection apparatus and topped up to an accurate weight by the filling apparatus, thus avoiding overfilling with its inherent loss of profit.

3. By providing the mechanical folding apparatus, problems with finger contamination of the surface of the inlet portion of the bag. can be eliminated. Furthermore, problems inherent with manual operation such as lack of uniformity of the surfaces resulting in wrinkles and affecting the subsequent sealing operation can be eliminated.

4. Manual workers performing the bag folding operations on a continuous basis have been affected by"Occupational Overuse Syndrome". The invention eliminates this problem.

5. By providing the posidoning apparatus prior to the check weigher and top up apparatus 12 and the vacuum sealing apparatus 20, then problems due to inaccurate alignment of the bag on the conveyor path can be eliminated.

Finally it will be appreciated that the present invention has been described by way of example only and that modifications and additions may be made thereto without departing from the scope of the invention as defined in the appended claims.

Claims

1. A method of filling a bag, comprising the steps of ; providing a double plane support device comprising a first plane support surface and a second plane support surface inclined and positioned relative to each other such that a bag to be positioned can be supported by both of the support surfaces when the planes are tilted as one to a predetermined inclination, and mounting the double plane support device such that in a final condition an intersection of the first and second planes is at a predetermined position with respect to the conveying path ; tilting the double plane support device such that the first plane support surface is substantially horizontal; loading a bag by displacing product horizontally into the bag while the bag is horizontal; placing the thus loaded bag onto the first plane support surface; tilting the double plane support device to a final condition such that the bag

slides on the first plane support surface to rest against the second plane support t : l surface, whereby the bag becomes upright ; weighing the loaded bag to predetermine a top-up charge of product to achieve a target weight of the filled bag ; adding the predetermined top-up charge to the loaded bag ; and closing the thus filled bag.

2. A method according to claim 1, and further including the steps of :- providing a second said double plane support device; tilting said second double plane support device such that the second plane support surface thereof is substantially horizontal; placing the filled and closed bag on said horizontal second plane support surface; and tilting said second double plane support device such that its first plane support surface is substantially horizontal, whereby the filled bag becomes

horizontal.

3. A method according to claim 2, further comprising the step of evacuating and sealing the thus closed bag.

4. A method according to any one of claims 1 to 3, wherein the product is a z : l block of cheese and the top-up charge of product is crumbled cheese having been advanced by an auger.

5 A packaging apparatus adapted for packaging a product which is moved substantially horizontally into a bag, said packaging apparatus comprising :-

a bag filling apparatus including a bag supply means, means for supplying a t : l 9 bag from the bag supply means, means for holding an inlet region of the bag open to receive said product, and means for advancing a product substantially horizontally receive sal I z : l into the bag ; positioning apparatus in the form of a double plane support device comprising a first plane support surface and a second plane support surface aligned substantially perpendicular to each other, the support surfaces having a device for supporting a product resting thereon and moving or allowing movement of the product in a longitudinal direction mutually parallel to the planes, and a mounting device for supporting the double plane support device so as to be movable between a first position wherein the first plane support surface is substantially horizontal, and a second position wherein the second plane support surface is substantially horizontal, means for advancing the bag with product therein from said bag filling apparatus to said positioning apparatus ; bag weighing apparatus for weighing the bag loaded with product therein; and supplementary filling apparatus responsive to said bag weighing apparatus and capable of filling additional product into a bag subsequent to its having been loaded and placed upright by said positioning apparatus.

6 A packaging apparatus according to claim 5, wherein said supplementary filling apparatus comprises discharge means mounted over a conveying path of said packaging apparatus downstream of said bag filling apparatus, the discharge means being capable of discharging additional product downwards from an outlet, and means for moving said discharge means relative to said conveying path.

7. A packaging apparatus according to claim 5 or 6, and further comprising evacuating means downstream of said supplementary filling apparatus for removing gas from inside said bag at the time of folding, and sealing means for sealing said bag once gas has been removed.

8. A packaging apparatus according to claim 7, wherein said evacuating means comprises a passage formed inside at least one of said fingers, and means for removing gas from said bag via said passage.