Patent Application
20230034751
This application claims priority to German Patent Application No. DE 102021119720.1 filed on Jul. 29, 2021, the disclosure of which is incorporated in its entirety by reference herein.
The invention relates to the precise depositing of a portion consisting of one or more parts, in particular foodstuffs.
Although such a part can also be a whole foodstuff, such as a piece of fruit, it is generally a part previously separated from a whole food piece, such as a slice of pineapple or a raw cutlet or steak cut from a piece of meat.
Such portions are usually sold shrink-wrapped in supermarkets and lie on a packaging element, either a flat, so-called cardboard, i.e., a plate made of plastic or clay material, or in a packaging trough, e.g., a thermoformed plastic packaging. Other types of packaging elements are also possible.
A sealing film extends over the foodstuff in the completely packaged product and is sealed tightly to the packaging element, i.e., either welded to the edge of the trough-shaped thermoformed packaging or tightly fastened to the cardboard, in particular to the underside of its edge.
For this purpose, it is necessary that the portion consisting of one, but usually several, parts is in a predetermined defined position on the packaging element before the sealing film is applied, in order not to make the application of the sealing film more difficult, in particular by the portion not extending into the area of the packaging element where the sealing film is to be fixed. Furthermore, by arranging the portion in a defined position and also the correct arrangement of the parts of a portion relative to one another, an attractive uniform visual appearance is desired.
Furthermore, portions also frequently consist of non-identical parts, whereby the parts are to be arranged in a specific sequence within the portion.
For the precise positioning of the portions and also the assembly of the portions, it has been common practice up to now for slices cut from a piece of meat—which will be referred to primarily in the following—or also parts cut off in some other way, such as the legs or wings of a chicken carcass, for the cut-off parts first to fall individually from the cutting device, in particular a slicing device, onto a feed conveyor unit to the packaging machine. There, they are grouped into portions or at least partial portions and dropped from this feed conveyor —which is often made up of several parts in the transport direction—onto the packaging element positioned in front of and below the ejecting feed conveyor. For this purpose, the packaging element must of course be positioned exactly in terms of position and rotation at this pick-up position, and this at considerable speed, since the cycle time for cutting slices from a product piece is often less than 0.5 seconds.
The packaging element is also usually transported and positioned by means of a conveyor belt, for which special forms of conveyor belts, which are constructed in a correspondingly complex manner, also enable a transverse offset of the packaging element and/or a rotation of the packaging element about the vertical axis.
However, it must be borne in mind that high hygiene requirements exist in the processing of foodstuffs and therefore, for all parts coming into contact with the foodstuff, on the one hand, there is only a narrow choice of material and, on the other hand, it must be possible to clean the device easily and thoroughly, which can be a considerable expense, particularly in the case of conveyor belts, even if these belt conveyors are designed in such a way that the conveyor belt can be removed relatively easily and cleaned separately.
It is therefore the object of the invention to provide a method for the positionally accurate depositing of a portion on a packaging element, as well as a suitable storage device for this purpose, in which the error rates in the positionally accurate depositing are lower than with conventional solutions, even with products that are difficult to handle, such as elastic slices of meat, and in which the device is easy to keep clean and to clean.
With regard to the method for the positionally accurate production of a portion from one or more parts in or on a packaging element, this task is solved by the sequence of the following steps:
However, before this:
Instead, this vehicle, which is referred to as “driveless”, is driven from below the driving surface—on which it is driving or above which it is hovering—whereby certain drive elements necessary for this purpose can be located inside the vehicle, such as permanent magnets, but indispensable parts of the drive are not located in the vehicle but below the driving surface in a driving floor or above the driving surface in a driving corner, for example an array of electromagnets.
In this way, the driveless vehicle can be moved by means of the e.g., the driving surface, and can also be positioned under the discharge end of the feed conveyor unit at a catch position defined with respect to the position and/or the rotational position for catching the portion or partial portion discharged by the discharging feed conveyor, as a rule in the case of several feed conveyors the last feed conveyor in the conveying direction, in such a way that the discharged portion or partial portion hits the packaging element in the desired position—with respect to position and/or rotational position.
During jettison, the vehicle will usually be stationary at a defined arresting position, which depends on the arresting parameters prevailing during jettison, i.e., all parameters that influence the jettison process on both the jettisoning side and the arresting side, such as:
However, in order to prevent the slice from folding on the packaging element, it can also be useful for the packaging element, and thus the vehicle, to move in the direction of ejection, ideally at a speed corresponding to the horizontal component of the ejection movement at the time of impact on the packaging element.
In this way, the necessary positioning, also with regard to the rotational position, is handled by the vehicle alone, so that on the one hand only a small number of individual feed conveyors are required, and on the other hand the feed conveyors, in particular as belt conveyors or strap conveyors, can be of a very simple design, i.e., they do not have to be an expanding belt, nor do they have to be a belt enabling the rotation of the product lying on it, nor do they have to enable a transverse offset of the product lying on it.
This also considerably reduces the number of parts of the depositing device that are difficult and costly to clean, because the driving surface on or over which the vehicles move can be a smooth, dense, easy-to-clean surface, usually made of stainless steel, which is very easy to clean.
First of all, it should be clarified that there are in principle two different, also combinable, ways to produce a portion consisting of several parts—be their parts touching each other, even overlapping, or not—according to such portioning parameters on the packaging element.
In method A, the portion to be produced or also only a part portion thereof, which, however, can also already consist of several parts, is already formed on the feed conveyor unit, in that several parts are deposited there on this feed conveyor unit in the form of a portion or part portion, i.e., in the correct assignment to one another, in particular one after the other in time.
In method B, the portion to be produced or a partial portion thereof, which may also already consist of several parts, is first formed on the packaging element by dropping one or more parts, in particular also a partial portion, by means of the devaluating feeder onto the packaging element on the vehicle, in particular one behind the other in time.
As can be seen, a combination of the two methods is also possible, for example by forming a portion on the feed conveyor and depositing these two portions one after the other on the packaging element.
In this way, there is a high degree of design freedom as to how the portion to be formed on the packaging element is produced there.
Theoretically, the part or portion can also be placed directly on the vehicle instead of on a packaging element, but this greatly complicates further handling of the part or portion and is therefore not a priority.
Important in this procedure is the exact determination of the pick-up position at which the vehicle and thus the defined packaging element positioned on it must be located when the part or portion is picked up.
For this purpose, various catching parameters are preferably taken into account which also determine this catching position and which must be known or must first be determined, which can be:
By means of these catching parameters, the control is able to calculate the catching position and to additionally optimize the calculation of this catching position by taking into account the positions of the preceding parts and, in particular, the trend of the change in position and/or rotational position from one drop to the next.
Often, when the part hits the packaging element, it will not be stationary, but will be in motion, including the supporting vehicle underneath.
Ideally, the horizontal speed of the vehicle should then correspond to the horizontal component of the ejection speed of the ejecting feeder, for which a fortiori some or all of the aforementioned catching parameters should be taken into account in order to correctly determine the speed and/or direction and/or rotational position of the packaging element at the moment of ejection at the catching position.
When producing portions, at least one portioning parameter must generally be observed, for example a target weight of the portion.
However, there are also portioning parameters that are more difficult to comply with, which is why, when creating portions, in particular from slices of meat, on such a packaging element, the slices should not be deposited on the packaging element as a portion in the order in which they are separated from the piece of meat, or, generally speaking, delivered parts of a foodstuff cannot or should not be deposited on the packaging element in the order in which they are delivered.
This can have different reasons.
When producing weight-accurate portions, it may be that the last slice to actually be added to the portion in order of separation would then result in a portion that is outside the permissible weight limits, and instead another slice with a higher or lower weight is to be added as the last of the portion.
Another reason can be, for example, optical reasons, in that one would like to have slices cut from a piece of meat that is irregular in the slicing direction also follow one another with regard to their position and thus possibly size in the piece of meat and/or their color and/or other sorting parameters—which characterize the individual slice.
For example, a portioning parameter may be that a portion should consist in the correct ratio and sequence of consecutive slices from different areas of the piece of meat from which they are cut, for example one slice from the starting area, 3 slices from the middle area and one slice from the end area of these pieces of meat.
Also such a portion cannot be obtained directly after the slicing machine. In this case, only a partial portion, for example the initial slice, is initially placed on the packaging element, which is then temporarily stored and, if further suitable slices are available, these are added.
Further sorting parameters for a single slice can be:
Such a portioning requires that parts currently transported towards the packaging element, but which do not meet the currently required sorting parameter, are not deposited on the packaging element, but are temporarily stored for use on another packaging element and/or until a part meeting the currently required sorting parameter is available.
According to method B above, such portioning can be performed only by means of the vehicle.
Thus, only a first part of the portion to be produced, be it a single part or a first part-portion, can be deposited on the packaging element of the vehicle, for example consisting of slices separated one after the other, because these have all fulfilled the sorting parameters to be fulfilled so far.
If the next part transported in the direction of the packaging element does not have the sorting parameter(s) currently to be fulfilled, the vehicle is moved away from the receiving position and parked offside, and only when a next suitable part is available on the ejecting feed conveyor, which therefore fulfills the current sorting parameters for this packaging element/portion, the vehicle is moved back to the receiving position and this suitable part is deposited on the packaging element.
The process of parking the vehicle away from the packaging element and only returning to the pick-up position when the next suitable part is available can also be repeated several times in succession until the desired portion has been completed.
Since a large number of such independently movable vehicles are generally available, portioning and delivery of the finished portion to a packaging machine is accelerated simply by the fact that, during the period in which a particular vehicle picks up a new part or a new portion, other vehicles simultaneously travel their routes for transfer to the packaging machine, to a parking position or from a parking position to the next pickup position to be approached, or their format plates are exchanged or cleaned.
The suitability, whether the part is suitable for the corresponding position within the portion to be produced or not, is thus determined on the basis of the sorting parameters, preferably of course automatically determined by means of the control and the corresponding sensor system connected to it for determining these sorting parameters.
For example, one of the feed conveyors of the feed unit can be equipped with a scale for determining the weight of the part or portion lying on it, a camera can be present above the feed conveyor for determining the size and/or position and/or rotational position, a speed sensor can be present on the drive shaft of the feed conveyor, in particular of the ejecting feed conveyor, for determining the ejection speed.
The portioning possibilities can also be created by other measures or further increased compared to portioning only with the aid of the vehicles in order to make portioning even more flexible.
For example, parts or portions that are currently not suitable can be stored separately from one another in intermediate storage.
Since each individual storage location in such an intermediate storage system fulfills the same storage function as a vehicle parked off to the side, the number of vehicles required and also the need for driving space and parking space for this can be kept low and/or the complexity of the portioning processes can be increased.
In order to keep the complexity of the drive and/or control system driving the vehicles below the driving surface within limits, the possible movements of the vehicles can be selected to be more or less varied.
If the vehicle does not also have to be able to rotate about its vertical axis when its direction of travel is changed, but instead continues to travel at an angle to this new direction with the same rotational position after the change in direction, this is a simpler solution to implement than to also effect a rotation of the vehicle about the vertical axis in an analogous and adapted manner when the direction is changed, so that the vehicle thus performs a typical cornering maneuver and always points with its front side in the current direction of travel.
It also simplifies the solution if a rotation of the vehicle about the vertical axis is only possible, for example, when the vehicle is stationary.
With regard to a storage device, this task is solved in that it comprises, on the one hand, a feed conveyor unit which takes over individual parts or portions or a whole portion from an original source of the parts, in particular a slicing machine, and feeds it to a packaging element and can drop it thereon.
On the other hand, the storage device comprises a vehicle system with a plurality of vehicles without drive alone, on which the packaging element is located. This vehicle system is designed in such a way that the vehicles travel on a travel surface or hover above a travel surface and can be driven independently of one another by a drive arranged below the travel surface, preferably contactlessly, for example magnetically, and can thus be positioned precisely in terms of position and/or rotational position at a collection position below the dropping feeder.
Parts of the drive, for example permanent magnets, may well be located in the vehicle, but not the entire drive, so that the vehicle cannot be driven without drive parts located outside the vehicle.
Furthermore, a control is provided for controlling at least moving parts of the unloading device.
The vehicles are the vehicles of a vehicle system which, as described above, are not capable of driving on a movable driving surface on their own, but only with the aid of the specific drive present under the driving surface in the driving plate, whereby parts belonging to this drive, such as magnets, may well be arranged in the vehicle.
The existing control system controls both the vehicle system and the feed conveyor unit for this purpose, whereby the vehicles can be moved independently of one another on the driving surface or hover above the driving surface at a distance and can thus also be positioned exactly in terms of position and rotational position at a collection position specified by the control system below the ejecting feed conveyor.
Despite only a few, ideally only one, infeed conveyor, this creates a highly flexible storage device.
As different packaging elements—depending on the order, if necessary—can even be Since different packaging elements have to be used—depending on the order, if necessary even mixed during the cutting of one and the same batch of food pieces—each vehicle preferably has a mounting device, with the aid of which a format plate can be fastened in a defined position, in particular positively, in a very simple manner on the upper side of the vehicle, which format plate is matched in terms of position and design on its upper side, for example by means of positively locking mounts and stops, to the packaging element to be arranged on it, which can thus be arranged in a defined position on the format plate and thus on the vehicle.
Preferably, the fastening device is designed in such a way that one and the same format plate can also be positioned on the vehicle in several different positions, for example rotated by 90° relative to one another or offset in one of the horizontal extension directions of the vehicle. This further increases the variability of the storage device.
Preferably, the driving surface consists of a closed and preferably flat and/or dense upper surface of a driving plate, which is made of a material that is easy to clean, in particular stainless steel.
In this way, completely different portions can be produced from one batch of food pieces to be cut open, for example portions only from the initial part of the food piece or portions only from the middle part of the food piece or also portions mixed with parts from different areas of the food piece.
Embodiments according to the invention are described in more detail below by way of example. They show:
As best shown in
The vehicle system 2 comprises a plurality of vehicles F, in this case F1-F10, which are capable of being moved independently of each other in a controlled manner on the moving surface 3″, which is spanned by the X and Y directions and on which the vertical Z is preferably perpendicular.
However, the vehicles F do not have their own drive motor with which they can travel on any travel surface by means of wheels, for example, but are quasi-driveless, since the main part of their drive is located under the travel surface 3″ in the travel floor.
This consists, for example, as seen in plan view, of an electro-magnet as bottom magnet 4a—only indicated in
The vehicles F also have magnets on their underside, but preferably permanent magnets as vehicle magnets 4b, likewise distributed in a grid-like manner over the bottom surface of the vehicle F, preferably with the same grid orientation and preferably the same distances of the vehicle magnets 4b as those of the bottom magnets 4a. The vehicle F is thus moved in a desired direction by selectively actuating certain bottom magnets 4a in a time-delayed manner.
On the upper side of the vehicle F there are one or more fastening devices 6 which permit the fastening, preferably by form-fit attachment, of a format plate 5, the upper side of which allows form-fit attachment to the shape and dimension of the packaging element V to be placed thereon, in this case a tray V in the form of a trough.
The format plate 5 can also project laterally, even in all directions, over the vehicle F as seen in plan view, and in particular the fastening devices 6 are arranged in such a way that the format plate 5, as seen in plan view, can be placed and fastened on the vehicle F in a plurality of rotational positions which differ from one another, for example by 90°.
Where the feed conveyor unit 10 obtains the parts T to be transported by means of the vehicles F and also to be stored between them, and which parts of foodstuffs—be they whole food pieces or parts of food pieces—are involved, is irrelevant to the present invention.
Shown as parts T are the slices S of a food piece LS to be sliced, such as a piece of meat, which in this case is pushed forward obliquely downward in a forming tube 11, and the protrusion of which over the forming tube 11 is cut off by a blade 13 which is movable back and forth transversely to its direction of extension, in this case rotating, whereby the cut-off slice falls flat onto the beginning of the feed conveyor unit 10 due to the oblique position.
In order to determine the thickness of the slices S, the food piece LS, in this case the piece of meat, is pushed forward in the forming tube 11 by means of a longitudinal press stamp 12 until it reaches a stop plate 14, which together with the blade 13 can move back and forth transversely to the direction in which the forming tube 11 extends.
This food piece LS in the form of a piece of meat is shown again separately in side view at the top left of
As a rule, such a piece of meat is not cuboidal, but has an increasing and decreasing cross section at the beginning and end, respectively, as schematically indicated.
Depending on whether the forward pushing by means of the longitudinal press stamp 12 results in a compression of the slice of meat LS or only in a forward pushing, the slice of meat LS also assumes in its initial and final sections the cross section of the forming tube in which it is accommodated, or only partially or not at all, so that with unchanged slice thickness the slices become of different weights.
Likewise, the initial part and the final part of the piece of meat may differ from the central uniform part also in other parameters, for example, its color, fat content, and the like.
Frequently, however, portions P are to be produced on the packaging element V from several, here in each case three, mutually partially overlapping, i.e., shingled slices as shown in
The slices S1 to S4 from the initial portion or S25 to S30 from the final portion, which have a different appearance and/or possibly a different weight or size, should not form the uppermost but rather the lowermost slice of the portion P on the packaging element V and must therefore be dropped first onto a vehicle F with the packaging element V, but then it is necessary to wait until slices from the middle portion S5 to S24 are cut open and are available.
The problem arises that the slice S can experience a deflecting force due to the direction of rotation of the blade 13, which leads to the separated slice S on the feed conveyor 10, in particular after transfer from one conveyor to the next in the case of a multi-part feed unit, on the ejecting conveyor 10a is not always in the exact nominal position and nominal rotational position (viewed from above), which is, however, the prerequisite for this slice being in the exact nominal position there after ejection on the packaging element V. This, in turn, is necessary so that the edge of the slice S is in the exact nominal position.
This in turn is necessary so that the edge of the packaging element V, in this case the tray, is not covered or soiled by the slice S, since it is to be tightly sealed after complete filling with sealing film, which is to be tightly sealed onto this edge. In order to save packaging material, the packaging element V is also dimensioned relatively close to the portion P to be deposited.
With the vehicles F which can be moved on the moving surface 3″—if necessary also floating, however preferably sliding on sliding feet—both the buffer problem existing with a desired sorting within the portion P and the positioning problem can be solved exclusively with the aid of the vehicle system 2 and without further aids as shown on the basis of the
In
Furthermore, in
Since slices from the central area with a uniformly large cross section of the food piece LS, i.e., from slice S5 to S24, are desired on the vehicle F1 as further slices of the triple portion, the vehicle F1 loaded only with slice S1 is then moved to a parking position as indicated, and one of the further vehicles F2 to F10 shown in the parking position with still empty packaging element V is used, for example the vehicle F2, as already shown according to
The now foremost slice S3 of the piece of meat is already in contact with the stop 14 and is ready to be cut off by the blade 13 in order to then be deposited by the infeed conveyor unit 10 on the vehicle F3 and its packaging element V and to then also move the vehicle F2 into a parking position as shown in
However, the following slice S4 is the last slice of the front end area of the piece of meat. This is deposited on the vehicle F4, for example, but since slices S5 and S6 now follow from the uniform middle section, these can be separated immediately afterwards and also deposited on the vehicle F4, as can be seen in
Then, according to
In the same way, the portions are then completed on the vehicles F2 and F1, for which the slices S9, S10 and S11, S12 are used.
After this, there may be no more part portions to be completed on vehicles, so that now the remainder of the central part with slices separated in each case in sequence can also be created in portions deposited in sequence in a vehicle, as shown in
The last vehicle which can be completely loaded with slices from the center section is the vehicle F8 carrying the slices S22 to S24, as shown in
Here it can be seen that the last slice S24—merely as an example—was lying twisted on the discharging conveyor 10a, which is why the vehicle F8 for collecting the slice S24 is also positioned at an analogous angle and, if necessary, not at the same transverse position in the conveying direction as the discharging conveyor 10a at the collection point, in order to produce a portion P consisting of shingled slices S22 to 24 which are exactly aligned with one another.
The position and rotational orientation on the dropping conveyor 10a has previously been determined by the position detector 8, preferably a camera 8 suspended above this dropping conveyor 10a, and reported to the control.
The next slice S25 subsequently waiting to be separated from the piece of meat LS is the first slice of the rear end region and is already somewhat smaller than the slices S5 to S24 of the middle region and, according to
Since in this case the rear end section is longer than the front end section and comprises a total of six slices, six of the total of ten available vehicles are used in this condition for intermediate buffering of one slice each of the rear end section.
Subsequently, the procedure is the same as described for the beginning of the piece of meat LS, but with the following difference:
While in the first slice of meat LS after slice S12 no more vehicles with unfinished portions were in waiting position, now from the end of the first slice of meat LS, e.g., six vehicles are in waiting position, each loaded with a smaller slice from the rear end area. Each of them, starting from slice S13 of the middle area, is again driven under the dropping conveyor 10a and two slices, e.g., S13 and S14, are deposited thereon one after the other in order to complete a portion there on three slices, for which all slices up to slice S24 of the middle area are required until the last of the six buffering vehicles.
Then the slices of the rear end section of the next piece of meat LS are again buffered individually on one vehicle each and this is moved to a parking position.
Depending on how long the initial and final sections of such a piece of meat are, a relatively large number of vehicles F of the vehicle system 2 may be required merely for the intermediate buffering of, for example, one slice each from the final section.
Since the vehicles F are expensive to purchase and, in particular, the required parking space is expensive since it must also be occupied by bottom magnets 4a, it may be worthwhile to provide another buffer instead of and/or in addition to the vehicles F of the vehicle system 2.
Thus,
For this purpose, as seen in plan view, this upstream conveyor 10b extends from its upstream end in conveying direction X into the intermediate storage 17 up to its downstream end, whereby the slice S is located in the longitudinal area of the intermediate storage 7 in the X-direction, as shown in
This is possible in that—as shown in the enlargement in
The cooperating conveyor 10b, which is designed as a belt conveyor, consists of these synchronously driven straps 20.
The straps 20 rotate at their upstream end outside the bearing shelf 7 over a common driven deflection drum 20a extending over the entire width of the conveyor 10b. At its downstream front end projecting into the bearing rack 7, each strap 20 rotates over its own separate deflecting roller 20b, which are not connected to each other in the transverse direction Y, but are each connected to each other by a not shown deflecting roller 20b running in the conveying direction X. The deflecting rollers 20b and 20b are driven by the conveyor 10b, upstream of the storage rack 7, the free distance in the transverse direction Y between the individual deflection pulleys 20b, as seen in plan view, being large enough for one support bar 19 each to be able to move through them in the vertical Z.
By raising the storage rack 7 in such a way that a shelf 18, which previously was with the upper side of its support bars 19 still below the upper side of the upper spaces of the straps 20 of the conveyor 10b—as shown in
In this way, the storage rack 7 can be filled with, e.g., a slice S, starting with the uppermost compartment 7a and from there continuously downwards, until they are required again.
For removal, a shelf 18 on which a slice S lies is moved analogously in reverse to just below the upper side of the tops of the straps 20 of the conveyor 10b, so that the slice S is then driven in the direction of rotation on the conveyor 10b whose straps 20 are then driven in the direction of rotation, whereby the slice S is transferred to the following downstream conveyor 10a in alignment, as can be seen in
In this way, the intermediate storage 17 can be emptied compartment by compartment, but as can be seen only in the order of the filled compartments from bottom to top, so that such an intermediate storage 17 can only be operated according to the last-in-first-out principle.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102021119720.1 | Jul 2021 | DE | national |
