WO2016130018A1

WO2016130018A1 - Method and device for palletizing packages from a rack to a supporting device

Info

Publication number: WO2016130018A1
Application number: PCT/NO2016/050021
Authority: WO
Inventors: Arne Einar AASEN; Magne STAURSET
Original assignee: First Process As
Priority date: 2015-02-11
Filing date: 2016-02-11
Publication date: 2016-08-18
Also published as: NO336587B1; EP3344566A1; EP3344566A4; NO20150199A1

Abstract

Method and device for palletizing packages (2) stored on shelves (9) in a storage rack (1a) using a palletizing unit (10) having a loading station (5), an unloading station (3) and a package moving device (8) horizontally moving packages simultaneously from the shelves (9) of the rack (1a) to intermediate storage plates (6) extended to a position above a pallet (4). The packages are then deposited in layers on the pallet by withdrawing the extended intermediate storage plates (6) one by one and starting from the lowest one, with the pallet or its top layer brought into position immediately below the lowest extended intermediate storage plate (6).

Description

METHOD AND DEVICE FOR PALLETIZING PACKAGES FROM A RACK TO A SUPPORTING DEVICE

Field of invention

The present invention relates in general to a method and device for automatically transferring packages stored in a stacked manner on shelves in a rack device and over onto a supporting structure, such as a pallet. More specifically, the invention relates to automatically palletizing packages, for example packages with frozen contents in the fishing industry, stored on purpose built shelves or racking devices.

More specifically the present invention relates to a method and a device for palletizing packages stored on shelves in a multi-shelf storage rack, using a palletizing unit provided with a loading station, an unloading station, a device for moving packages on the shelves of the rack horizontally from the rack towards a position above a pallet and a device for transferring the packages onto the pallet. The method comprises placing the multi-shelf rack containing the packages to be palletized at the unloading station; placing the pallet in a loading station; moving the packages horizontally from the shelves in the rack to a position above the loading position; bringing the pallet in position immediately below the packages at the loading station whereupon the packages are placed on the pallet; and whereupon the emptied rack and the completely palletized pallet eventually are moved away form the unloading station and loading station respectively.

Background

The pelagic and aquaculture industry is increasing rapidly throughout the world and efficient packaging and transport of frozen marine products are of great importance. The catches at sea or organisms harvested from marine farms are frozen immediately after being taken out of the water in order to preserve the quality. Alternatively, the catch is transported to plants onshore for packing and freezing, stored in shelves in a rack during the freezing process. The freezing process is normally done by putting packages of products in racks with free space around the layers of packages in order to give a cooling medium (for instance cold air) access to all sides of the packages and thereby speed up the freezing process. Upon a completed freezing process, the packages are usually palletized for further storage and/or transport, for example by means ships and trailers.

Devises and arrangements for transferring package from the racks to a pallet are known in the industry prior to the present filing date. Such devices and/or systems may for example be a device or system marketed and sold as far back as the late 90es by a Norwegian company. Said palletizer consisted of a transport conveyor for transport of a multi-shelf rack, filled with frozen packages, a transport conveyor for transport of a pallet and upon completed palletizing process, a pallet with packets stacked at several heights. The device is provided with a loading station for transferring packages onto the pallet and an unloading station where packages stored on the shelves of the multi-shelf rack are transferred to the pallet. At the loading station the unit is provided with a lift for lifting the pallet with or without loaded packages up and down, while at unloading station, the device is provided with a lifting table based on a scissor mechanism, lifting and lowering the rack. At the upper part of the device, a moving means is arranged, configured to move three heights of packages at the time from the rack over to a guiding device for guiding the received packages during the transfer from the shelf until said packages can be placed on the pallet below. Both the moving means and the guiding device are fixed against vertical movement at the top of the device. This device functions as follows:

Racks may be placed on the transport conveyor, the first of which being moved to the unloading station, while a pallet is placed on the other transport conveyor and moved to the loading station, the two stations being adjacent to each other.

- In case the top shelves of the rack are not aligned with the moving device, the rack is adjusted vertically in order to align the shelves of the rack with the corresponding moving devices.

- The moving device is then actuated, pushing three shelves out of the rack at the time to three intermediate supporting plates on to the temporary storage device above the loading. Each intermediate supporting plate is formed of two halves, each half moving sideways to each side in order to subsequently allow the packages to land on the pallet just below.

- By means of the lifting table, the pallet is then lifted vertically upwards by

means of the lift to a height just below the guiding and temporary storing device, whereupon the packages on the intermediate support are released and the packages are transferred on to the upper surface of the pallet.

- The pallet lift must then be lowered down and the intermediate storage plates have to be retracted to the position for receipt of the next batch of packages, before such packages can be pushed over and onto the temporarily supporting plates from the rack.

- The rack is now lifted vertically upwards so that the next shelves with stored packages become aligned with the guiding means. - The steps described above are continued until the rack is emptied, whereupon the emptied rack is removed from the unloading station and a new, package storing rack is brought into the unloading station. If the pallet is filled up to the required height, the pallets are also transported away and a new pallet is brought to the loading position and lifted to a height just below the guiding means.

According to such solution, the entire rack has to be emptied before removal of the empty rack and substitution of a new rack to be palletized. In addition, only the packages in three shelves on the rack can be emptied in one transferring sequence. Moreover, upon completed emptying of three shelves, the rack must be lifted up enabling transfer of the next group of shelves to the loading position. Not until all packages from the rack have been transferred to the loading station, the rack is allowed to be lowered down again to the conveyor for removal and substitution of a new rack to be palletized. Consequently, such solution has a detrimental effect on the palletizing capacity of the unit.

The next generation of palletizing apparatus, as discussed above, has been sold and marketed under the trademark 'Safe 3000 palletizer™' prior to the present application. This generation system comprises an unloading station; an elevator arrangement; a moving device for moving packages from the shelves of the rack to the loading station, a loading station and transporting conveyors associated therewith. The elevator arrangement is configured to move both in vertical direction and is provided with means for moving packages in horizontal direction. The loading and unloading stations are positioned in spaced relation to each other, distanced apart, in order to allow the holding device to move up and down in the space between the loading and unloading station. A multi-shelf rack, more or less filled with packages, is placed on the conveyor and moved to the unloading station and correspondingly, a pallet is placed on a second conveyor and moved to the loading station. The moving device is provided with vertically spaced pushing means and is mounted on a lifting arrangement that is configured to move vertically up and down. The pushing means are configured to be movable in horizontal direction in order to push packages on two or four shelves in the rack that is to be emptied at the time, pushing said packages from the two or four shelves onto a holding means on the elevator arrangement. The elevator with the moving means is positioned between the unloading and the loading space and configured to move up and down in vertical direction in order to receive the packages pushed out by the mover device to the holding device on the elevator. Moreover, the holding means is provided with a device configured to be moved laterally from a position between the loading and unloading station to a position above and over the loading station. In order to receive the two or four layers of packages from the rack, the elevator arrangement also has to be moved to and adjusted to the right vertical position. A stop wall is then elevated so that the shelf of the elevator arrangement with packages thereon can pass under it and the shelf with the packages is then positioned above the pallet, The stop wall is then lowered in order to prevent the packages from detrimental displacement when the shelf is retracted and the packages drop on to the top layer of the pallet or onto the empty pallet. The process is then repeated.

This device functions as follows:

- One or more racks may be placed on the transport conveyor, the first of which being moved to unloading station, while a pallet is placed on the other transport conveyor and moved to the loading station, the two stations being adjacent to, but spaced apart from each other, with a distance corresponding to the width of the elevator with the holding device.

- The moving device with the pushers on the one side of the rack is lifted to the correct height. Correspondingly, the elevator with the holding device on the opposite side is moved vertically to the same height in order to enable receipt of the packages that is pushed out from the rack.

- When the elevator is lifted to the height corresponding to the height of the moving device, thus being horizontally aligned with moving device, the moving device is then actuated, pushing the packs off the respective shelves of the rack and onto the holding device on the elevator.

- According to this solution, neither the rack at the unloading station, nor the pallet at the loading position is moved vertically up or down, both units being stationary and fixed during this part of the palletizing operation.

- Depending on which height on the rack to be emptied and the level on the pallet for receiving a new layer, the elevator is moved and adjusted vertically until being correctly aligned.

- The holding part of the elevator is then activated, moving the holder

horizontally in above the pallet. If necessary, the height may be slightly adjusted so that the bottom surface of the lower part of the holder is slightly above the top surface of the pallet or the uppermost layer of packages on the pallet, before the packages are allowed to be released from the holder.

- The holder on the elevator are now retracted to its starting position between the loading and unloading position, whereupon the lift and also the moving device are moved vertically to new alignment with the shelves on the rack to be emptied. - The process is repeated until all shelves or the required number of shelves in a rack has been emptied, whereupon the emptied rack is removed from the unloading station and a new, package storing rack is brought to the unloading station. If the pallet is filled up to the required height, the pallets may also be transported away and a new pallet is brought to the loading position.

FR 2844259 describes a pallet support that can be moved vertically up and down and receives layers of products piles arranged in rows. In between successive pile layers are support plates, which are supplied from a vertically mobile support arrangement. Product piles are moved onto the support plate from a co-planar conveyor belt using a pushing mechanism. The device comprises a pallet support that can be moved vertically up and down and receives layers of products piles arranged in rows. In between successive pile layers are support plates, which are supplied from a vertically mobile support arrangement. Product piles are moved onto the support plate from a co-planar conveyor belt using a pushing mechanism. Thus a layer of piles can be formed on a support plate and then the pallet support lower to commence the next layer.

US 2010189539 A1 relates to a device for stacking plate-shaped bodies, comprising the following features: a) a plate-shaped body is conveyed by a conveying device to the region of the push comb; b) the push comb pushes the plate-shaped body onto a surface that consists of the front tablet comb and the rear tablet comb; c) the retaining comb prevents a return movement of the plate-shaped body when the iron tablet comb and the rear tablet comb move apart from one another and controls the falling motion of the plate-shaped body onto the plate stack. The invention also relates to an associated method and a machine readable support provided with the program code for carrying out said method.

US 2869737 describes a palletizing machine comprising a pushing device to push a plurality of layers of objects onto a shelf and GB 1601284 describes a stacking machine comprising two movable plates.

The palletizing processes according to the prior art solutions are time consuming, since only a few of the shelves in a rack can be emptied at one go, and since the rack must stay in the unloading station until the last package is moved out of the rack and positioned on the pallet. Consequently, the rack cannot be replaced as long as the last part of the palletizing still is in process of being placed on the pallet..

Hence there is a demand for a more efficient and less time consuming solution, increasing the palletizing capacity. Summary of the invention

The principle used in the present invention is to use a support device for temporarily supporting packages during an intermediate stage of the palletizing process of transferring the packages from a multi shelved rack to a pallet and to maintaining the rack to be emptied in a stationary position until all packages are removed from the rack, the palletizing unit being configured to allow all shelves in a rack to be emptied in one synchronized, simultaneous movement, and configured to allow all the package on the support device to be transferred to the pallet by withdrawing at an almost simultaneous movement with only a small incremental time difference while moving the pallet synchronously in vertical direction upon the withdrawal of two neighboring support devices, whereupon the emptied rack may be substituted with a new, package filled rack while the temporarily supported packages still are loaded onto the pallet. The system is preferably powered by electricity.

An object of the present invention is to provide a method and a palletizing unit having improved efficiency and increased palletizing capacity.

Another object of the present invention is to reduce the time taken for completing a palletizing operation from a packaged filled rack on the transport band till a new package filled rack is ready for the palletizing operation.

Another object of the present invention is to provide a solution independent of vertical movement of the rack to be emptied during the palletizing stage.

Another object of the present invention is to provide a method and palletizing unit that is configured to empty one multi-shelf rack in one operation, allowing a new rack to be moved into the unloading position while packages from the previously emptied rack still is in the process of being transferred to the pallet.

An object of the present invention is to reduce the time where the frozen packages are exposed to thawing temperatures before being moved back to a low temperature storage facility or on to a transport device for export from the plant.

A further object of the present invention is to provide a palletizing unit and a method for palletizing enabling a new rack containing packages to be placed in the unloading position for the next palletizing operation, while the packages from the previously emptied rack still are transferred onto the pallet.

A further object of the present invention is to provide a palletizing unit where the possibilities for displacement or misplacement of the packages during transfer from the rack to completed transfer on to the pallet is eliminated, or at least substantially reduced.

A further object of the present invention is to provide a solution which is not prone to stacking failure even if the packing during the packaging and/or freezing process have been given a more or less different, none-uniform size and being rigid in shape, i.e. for example because of uneven or deformed sides, bottom or top, deformed during packing and freezing process.

Yet another object of the invention is to provide a palletizing unit and a method for palletizing packages being able to empty a multi-shelf rack in one emptying operations.

A still further object of the present invention is to provide an alternative method and a palletizing unit.

Another object of the present invention is to provide a guiding and positioning device, securing that packages are not displaced or become stuck during the process of transfer from the shelves on a rack to a pallet.

Another object of the present invention is to provide an alternative control system for monitoring and controlling the movement of a lifting device.

The objects are achieved by a method and a device as defined in the independent claims, while embodiments, variants or alternatives are defined by the dependent claims.

The method according to claim 1 and the device according to claim 5 solves these problems.

According to the present invention a method for palletizing packages stored on shelves in a multi-shelf storage rack is provided, using a palletizing unit provided with a loading station, an unloading station, a device for moving packages on the shelves of the rack horizontally from the rack towards a position above a pallet and a device for transferring the packages onto the pallet. The method comprises placing the multi-shelf rack containing packages to be palletized at the unloading station; placing the pallet in a loading station; moving the packages horizontally from the shelf in the rack to a position above the loading position; bringing the pallet in position immediately below the packages at the loading station where the packages are placed on the pallet; and whereupon the emptied rack and the completely palletized pallet eventually are moved away from the unloading station and loading station respectively. As part of the method, the following steps are carried out:

a. moving a number of retractable intermediate storage plates (6) at the loading station horizontally out from a retracted position to an extended position above said pallet (4), the number of plates being adapted to the number of shelves on the rack to be palletized in this loading step;

b. transferring at least some, preferably all, of the packages from shelves of a rack (1 a) to be transferred horizontally from the shelves onto the intermediate storage plates (6) above the pallet (4) substantially simultaneously by means of the package moving device (8);

c, moving the pallet (4) and/or the lower-most intermediate storage plate (6) close to each other; and

d. repeatedly:

• retracting the lower-most extended intermediate storage plate (6) to a retracted position in order to transferring the packages (2) onto the pallet (4), and

• moving the pallet including the packages (2) and the next lower-most extended intermediate storage plate (6) up to a position close to each other,

until all packages (2) from the intermediate storage plates (2) are located on the pallet (4).

According to another embodiment the method comprises the steps:

a. by moving a number of retractable intermediate storage plates horizontally to an outwards extending position, vertically above said pallet

b. all of the packages from the shelves in the rack are moved onto the intermediate storage plates above the pallet simultaneously by moving means, c. the pallet and the lower- most intermediate storage plate are moved close to each other,

d. repeatedly:

• retracting the at least one lower-most extended intermediate storage plate to a retracted position retaining the packages on the pallet, and

• moving the pallet including the packages and the lower-most extended intermediate storage plate to a position close to each other,

until all packages from the intermediate storage plates are located on the pallet.

In a different aspect the invention relates to a device for moving palletizable packages on shelves in a storage rack to a pallet, where the rack is placed in an unloading space, and the pallet is placed in a loading space wherein:. a. a first arrangement comprising a number of moving means, arranged to move some, preferably all, of the packages from shelves of a rack to be unloaded simultaneously to a number of retractable intermediate storage plates, which is equal to or lower than the number of moving means b. an unloading space located adjacent said first arrangement arranged to accommodate said rack to be unloaded, c. a loading space comprising an arrangement for moving said pallet to be loaded and the lower-most extended intermediate storage plate close to each other, said loading space being located adjacent said unloading space,

d. a second arrangement comprising said retractable intermediate storage plates, said plates being extendable to a position above said pallet, and located adjacent said loading space, wherein the number of extendable storage plates is equal to or less than the number of shelves in the rack. The purpose of the invention is to improve the speed of the palletizing process and /or decrease the energy consumed and the area that is needed to execute this process. The invention is performed by the features of the independent claims of the attached claim set. The independent claims represent preferred embodiments of the invention.

Moreover, according to the present invention a unit with an optimal foot print is provided, the unit also being simplified in that there is no need to move the rack to be emptied in a vertical direction. Moreover there is no need for adjusting a vertical movement of the rack nor the device for temporary storage of the packages.

Brief description of drawings

In order to understand the procedure and mechanics of the device, the

Figures provide an exemplary embodiment of the invention. In the Figures, only the principally important parts are shown. A lot of extra structures, fixtures, conveyors and power sources are not shown. The order of the Figures also represents a possible order of actions.

Figure 1 shows schematically and in perspective an assembled unit for palletizing packages, delivered to the unit by means of a rack;

Figure 2 shows a horizontal view of the assembled unit shown In Figure 1 , seen from above;

Figure 3 shows an initial position where a rack is located in the unloading position;

Figure 4 shows the intermediate storage plate being moved forward;

Figure 5 shows the moving means pushing all the packages from the rack onto the intermediate storage plates at the same time and two layers on each intermediate storage plates;

Figure 6 shows the pallet being lifted up to the lower-most intermediate storage plate and this being retracted; Figure 7 shows the pallet being further lifted and the next intermediate storage plate being retracted;

Figure 8 shows in perspective details of the assembled unit containing the intermediate storage plates according to the present invention;

Figure 9 shows in perspective and enlarged scale a view of the support and bearing of the intermediate storage plates;

Figure 10 shows in detail one possible driving and powering device for moving the intermediate plates from an inactive, retracted position to an active position for receipt of packages during the loading cycle;

Figure 1 1 shows in perspective, partly from the above, an embodiment for arranging the powering device and driving means for the top intermediate plate;

Figure 12 shows a horizontal view of the loading station seen from above, also showing part of the unit for the temporarily supporting, intermediate storage plates and also part of the unit for moving the packages from the shelves on the rack to the temporarily intermediate supporting plates;

Figure 13 shows in perspective, from the front the unit for moving the packages from rack to the intermediate storage plates;

Figure 14 shows in perspective parts of the unit containing the intermediate storage devices and the loading station with guiding panels and indicating the lift system; and

Figure 15 shows the lifting system 40, where the other parts forming the loading station are deleted from clarity point of view.

Detailed description of the invention

In the Figures, standard elements, such as the conveyors, the lifting table for lifting the pallet up and down and the structural elements for carrying the various parts are omitted for clarity reasons.

Figure 1 shows schematically and in perspective an assembled unit 10 for palletizing packages 2, delivered to the unit 10 by means of a rack 1 a (not shown in Figures 1 and 2), while Figure 2 shows schematically a view of the assembled unit 10 seen from above. In general, the assembled palletizing unit 10 comprises a unit 20 containing moveably arranged intermediate storage plates 6, a loading station 5, an unloading station 3 and a unit 30 incorporating moving devices 8 for moving or pushing packages 2 off the shelves 9 of a rack 1 a onto the intermediate storage plates 6, where these are in an outwards extended position above the loading station 5. The palletizing unit 10 comprises also a lifting arrangement 40. It should be noted that the palletizing unit 10 also comprises a metal framework 12 (not shown in Figures 1 -7), supporting and interconnecting the various units. Such metal frame work may be given sufficient strength and rigidity to support the various functions described below.

According to the embodiment disclosed in the drawings below, the palletizing unit 10 is configured in such way that the direction of movement of the intermediate storage plates 6 are moveably arranged in a direction parallel with the direction of motion of the racks 1 a to be emptied and the direction of the pallet 4 prior to and subsequent to completed palletizing process. Moreover, the direction of movement of the moving device 8 is chosen to be perpendicular with respect to the direction of motion of the intermediate storage plates 6, and the direction of motion of the racks 1 a, 1 b and the pallet 4. Consequently the configuration of the foot print of the disclosed embodiment has e general L-shape, where the pallets are configured to be moved beneath and through the unit 20 for the intermediate storage plates 6 to the loading station 5, the loading station 5 corresponding to the vertical space into which the intermediate storage plates 6 are moved when moved out to an outwards projecting position.

It should be appreciated, however, that the unit 20 containing the intermediate loading plates 6 alternatively may be arranged so that the plates 6 may be moved in the same direction as the moving device 8, i.e. in a direction perpendicular to the direction of motion for the racks 1 a, 1 b and the pallets 4.

The palletizing unit 10 comprises a loading station 5 and an unloading station 3. At least the loading station 5 is associated with a conveyor system for transport of pallets into the loading station 5 and for removal of palletized pallets out of and away from the loading station 5. At the loading station 5 a lift arrangement is provided in order to lift the pallet 4 in an incremental manner upwards during the palletizing process, and for lowering the pallets 4 with palletized packages 2 in a more or less continuous manner. Also the unloading station 3 may preferably be associated with a conveyor system (not shown) for moving filled up racks 1 a into the unloading station 3 and removal of emptied racks 1 b from the loading station. The palletizing unit 10 also includes a metal framework 12, serving as a structural frame and support for the various elements forming the part of the palletizing unit 10 as further indicated in the drawings 8-13. The built-up of such metal framework will not be described in further detail. As indicated the loading station 5 and the unloading station 3 are positioned adjacent and immediately next to each other, leaving merely space for the intermediate vertical structural supporting elements and the lifting arrangement 40 for moving the pallets 4 vertically. Moreover, the assembled palletizing unit 10 comprises a unit comprising moving device unit 30. The moving device unit 30 comprises a number of moving devices 8 for pushing packages stored on the shelves of the rack 1 a over and on to the intermediate storage plates 8. The moving devices 8 are arranged in and supported by a metal frame, connected to the unloading station 3 and the loading station 5, including intermediate storage plates 6, in an aligned manner so that when these are in the active position, projecting out and into the space above the pallet 4 in the loading position, the packages 2 may be pushed from the rack 1 a onto the plates 6 by means of the moving device 8 in a continuous manner without meeting any detrimental obstacles during such transfer. Since there may be a small vertical slot or space between the shelves 9 of the rack 1 a and the corresponding adjacent side edge of the intermediate storage plates 6, a fixed horizontal transition plate 1 1 for each intermediate storing plate 6 may be arranged aligned with the intermediate storage plate 6 and the corresponding upper surface of the adjoining shelf 9 of the rack 1 a.

Further details of the assembled palletizing unit 10 and its functions shall be described in further details below, referring to the drawings 3 to 13, where, from a clearness point of view, the assembled palletizer unit 10 in Figures 3 to 7 is shown without the structural supporting metal frames.

Figure 3 shows an initial position of a rack 1 a, loaded with packages 2, suited for palletizing - typically one layer of packages on each shelf for better cooling. The rack 1 a, loaded with packages 2, is placed in an unloading position 3 in the space between the unit 30 containing the moving devices 8 and the loading station 5, i.e. the position beneath the intermediate storage plates 6 when these are in a fully outwards extended, active position. Simultaneously, a pallet 4 is positioned beside the rack 1 a in the loading space 5, the pallet being moved to the loading position 5 from a pallet reservoir (not shown) along a conveyor arranged beneath the unit 20 containing the intermediate storage plates 6. It should be noted that according to the embodiment shown, the loading position 5, with the lifting arrangement 40 for moving the pallet 4 vertically up and down, and the unit 20 containing the intermediate storage plates 6 are jointed together by means of structural metal structures or assembled to form an integrated unit. A number of retracted intermediate storage plates 6 are positioned close to the loading space 5.

Firstly, the intermediate storage plates 6 are moved horizontally outwards from its retracted position to an extended position above the pallet as shown in Figure 4. The intermediate storage plates 6 may be horizontally retracted and extended in a direction parallel to or at a right angle to the moving direction of the moving devices 8. The pallet 4 is resting on a device 7 preferably a small roller conveyor 7 which can be lifted vertically towards the intermediate storage plates 6, by means of the lifting arrangement 40, so that the layer(s) of packages resting on the intermediate storage plates 6 can be deposited on the pallet or the top layer of packages on the pallet 4.

Secondly, as shown in Figure 5, the moving devices 8 push or move preferably all the packages 2 from the rack 1 a containing shelves 9 on to the intermediate storage plates 6 simultaneously and are then retracted back to their inactive position as shown in Figure 6. The number of moving devices 8 may be at least equal to the number of shelves 9 in the rack 1 a. It should be noted, that two and two neighboring moving devices 8 may be interconnected, driven by the same powering device and moving together, still emptying the shelves 9 in one go. In order to save time, it can be advantageous to push packages from at least two shelves simultaneously onto one intermediate storage plate 6. How this saves time will be explained below. In another embodiment the moving devices 8 move the packages from the shelves of the rack 1 a onto the intermediate storage plates 6 in a sequence starting from the bottom, that is fast enough to allow for an exchange of an empty rack 1 a, with a full rackl b in the unloading space before the loading of the pallet 4 in the loading space 5 is finished. As indicated in Figure 6, the emptied rack 1 b is then moved away from the unloading position 3, while a new rack 1 a, filled with packages are moved towards the unloading position 3.

Thirdly, the small roller conveyor 7 with the pallet 4 is lifted up/elevated towards the lowermost intermediate storage plate 6, ref. the vertical arrow in Figure 6. It is however also possible that the pallet 4 may be in a fixed position and that the intermediate storage plates 6 may be moved down towards the pallet 4 (not shown).

Fourthly, the extended intermediate storage plate 6 closes to the lifted pallet is retracted, starting by the lowermost intermediate storage plate 6 being retracted as indicated in Figure 6. Thereupon the pallet with the packages 2 resting thereon is lifted upwards toward the next intermediate storage plate 8 as indicated in Figure 7. It should be noted that the packages during transfer on to the intermediate storage plates 8 are guided by means guides (not shown) both sideways with respect to the direction of motion of the packages 2 and against an end stop (not shown). Such feature will be described in more detail below in connection with Figures 8-12. During retraction of the intermediate storage plates 8 the packages 2 are retained on the pallet 4 because of stopping means (not shown), preferably formed by the

corresponding side guides. Said guide may be a beam mounted just above the intermediate storage plates 6 stopping the packages 2 from moving back together with the intermediate storage plate 6. Then the pallet 4 including the packages 2 is lifted to a position just below the next intermediate storage plate 6 and the next intermediate storage plate 6 is retracted, and so on until all packages 2 from the intermediate storage plates are located on the pallet.

Fifth, while the intermediate storage plates 6 are retracted in an orderly fashion in step four, the empty rack 1 b may as indicated in Figure 7 be exchanged with a full rack 1 a, such full rack 1 a being now as shown in Figure 7 positioned in the unloading position, while the packages 2 still being transferred from the intermediate storage plates 6 on to the pallet 4.

Due to the fact that the rack can be emptied in one movement and

consequently that the empty rack 1 b can be exchanged while the packages 2 landed from this rack are palletized on the pallet 4 in the loading space 5, the time taken to exchange the emptied rack 1 b with a new, full rack 1 a is reduces. Due to the fact that the prior art elevator arrangement has been replaced by intermediate storage plates 6 already positioned above the pallet, the time it takes to move the elevator arrangement forward each time is saved. Due to the fact that there may be more than one layer of packages 2 on the intermediate storage plates 6, i.e. the number of intermediate storage plates 6 is half, 1/3, 1/4,.., etc. of the number of shelves in the rack, and consequently half, 2/3, 3/4, ... etc. of the time it takes to execute step four is saved (compared to only 1 layer of packages on each intermediate storage plate 6. In addition there might be a rest if the number of intermediate storage plates can't be divided by the number of shelves in the rack)

In an actual setting in the fish or aquaculture industry the present invention is expected to cut the time it takes to palletize a batch of processed marine products in half, where the capacity is typically increased from 40 tons/hour to 80 to 100 tons/hour. This extra capacity can also result in less space occupied by palletizing devices (one device is sufficient instead of two). As the current invention entails fewer steps, it is also expected to consume less energy per volume processed.

While the device and method has been described herein by way of examples in connection with what are, at present, considered to be the most preferred device and method, it is to be understood that the invention is not limited to what has been described above, but is intended to cover various combinations or modifications of its features, and several other applications included within the scope of the invention as defined in the appended claims. The details mentioned in connection with the description above may be used in connection with another embodiment when such combination is technically feasible. In the following the assembled unit 20 containing the intermediate storage plates 8 and the unit 30 containing the moving devices shall be described in more detail.

Figure 8 shows in perspective details of the assembled unit 10 containing the intermediate storage plates 8 according to the present invention. As specified above, the assembled unit 20 carrying the intermediate storage plates 6 comprises a frame of vertical and horizontal structural supporting beams 12, forming a structural open framework. Horizontal ducts or U- or L profiled rails 16 are arranged in pairs at same height on both sides of the unit 20 containing the intermediate storage plates 6, said pairs being arranged in spaced vertical relation, one pair for each

intermediate storage plate 6. Each plate 6 is powered by a motor 13, a toothed bar 14 and a corresponding gear wheel associated with the motor 13. As indicated, the loading station 5 is aligned with the unit 20, allowing the plates 6 to be moved into the space above the loading station 5. For such purpose, the frame forming the loading station 5 is also provided with pairs of corresponding horizontal ducts or U- or L profiled rails 16, arranged in pairs on both sides across the loading space 5, said pairs being aligned with the corresponding ducts or rails of the unit 20 containing the intermediate storage plates 6, said pairs being arranged in spaced vertical relation, one pair for each intermediate storage plate 6. Such alignment of ducts or channels 16 allow for smooth movement of the plates 6 horizontally into the space above the loading station and back to an inactive position upon completed transfer in each transfer cycle. Along the backside of the loading station 5 and vertically aligned with the ducts or channels 16, end stoppers or panels 17 are arranged, the purpose being to stop the movement of the packages 2 when pushed onto the plates 6 by the moving devised 8.

Figure 9 shows in perspective and enlarged scale a view of a portion of the plates 6 and the support or ducts 16, and the system for supporting the intermediate storage plates 6, allowing smooth movement in horizontal direction of the plates 6. According to the embodiment shown in Figure 9, the intermediate storage plates 6 are supported by a supporting system in the form of L-shaped rail or channel 16.

Moreover, along the side edges of the plates 6 rollers are arranged, one set of rollers 18 rotating around a horizontal axis while another set of rollers 18' is rotating around a vertical axis. In this manner, both vertical and horizontal forces are catered for and the plates 6 are prevented from sideways detrimental movement, allowing only movement of the plates 6 in intended direction. Alternatively for using rollers or roller bearings, the plates may for example slide in canals. Figure 10 shows in detail one possible driving and powering device for moving the intermediate plates 6 from an inactive, retracted position to an active position for receipt of packaged 2 during the loading cycle, while Figure 1 1 shows in perspective, partly from the above, an embodiment for arranging the powering device and driving means for the top intermediate plate 6'. The Figures disclose the part associated with the motors 13 shown in Figure 8, seen from the other side. The driving and powering device comprises a motor 13 driving a gear wheel 15. The gear wheel 15 is in driving contact with a toothed bar 14 arranged along one side of the plate 6. The toothed bar 14 may be arranged on the underside of the plate 6 as shown in Figure 10, possibly except from the top plate 6', where the toothed rod 14 is arranged on the upper side of the plate. The purpose for such alternative positioning is to cater for a reduced height available between the two neighboring upper plates 6, ref. the plate configuration disclosed in Figure 1 1 .

Figure 12 shows a horizontal view of the loading station 5 seen from above, also showing part of the unit 20 for the temporarily supporting, intermediate storage plates 6, the upper plate 6' being disclosed, and also part of the unit 30 for moving the packages 2 from the shelves 9 on the rack 1 a to the temporarily intermediate supporting plates 6. According to the embodiment shown, a pair of transmitters and a corresponding pair of receivers are fixed to the frame work diagonally across the loading station, used for controlling the height of the packages prior to being transferred to the pallet 4. At the end of the loading station 5, the loading station is provided with a two bladed door 19, each blade being configured to rotate around vertical axes 21 . As long as the transfer operation is in progress, the door 19 is closed, serving as a sidewise guide/stop for sideways displacement of the packages 2 during the transfer. The opening and closing of the doors may be powered by a motor 22 and a power transmission, preferably with a torque restricting device for each door blade 19, so that the doors may be opened and closed without imposing excessive loads on the transmission. At the rear end, i.e. the end arranged perpendicular with respect to the door, vertically arranged end panels 17 are arranged, serving as end stops for the movement of the packages 2 into the loading station 5. Such panels 17 are preferably rigidly fixed to the structural frame 12 and will also serve as a vertical guide for the packages during the vertical movement of the pallet 4 with palletized packages 2. Moreover, in order to prevent the packages 2

temporarily stored on the plates 6 to follow the plates 2 when the plates are retracted, vertical stop panels 23 are arranged perpendicularly across the direction of movement of the plates 6, forming a third barrier for guiding the packages. In the surface provided with the stop panels 23, slots or opening (not shown) allowing the plates 6 to pass, are arranged. Said stop panels 23 may be moveably arranged in a direction coinciding with the direction of motion of the plates, the stop panels 23 being moved into contact with the packages during the stage where the plates 6 are retracted, preventing the packages 2 from moving together with the plates. Hence, according to the present invention, the packages are guided and stopped from movement in three in three directions at the loading station 5, thus preventing displacement of the packages during the palletizing process. The only side not being provided with a guiding or stop function is the side facing the the unit30 for the moving devices 8, such retractable moving devices 8 functioning as a device for guiding the packages 2 during the stage where the packages 2 are transferred into the space above the loading station 5.

When a loading operation is completed, i.e. a pallet 4 is filled up with required number of packages 2, the door 19 is opened and the pallet 4, loaded with packages 2, is transported out from the loading station, while a new pallet 4 is brought into position.

It should be appreciated that two sets of through-beam photoelectric sensor with transmitter and receiver may be arranged for each shelf. The transmitters emit a light beam towards the receiver. When this beam is broken a signal is produced, communicated to the control system. The two sets of transmitters/receivers are mounted in a cross, so that the point of crossing for the two beams is approximately positioned at the center of the pallet 4. The distance between a transmitter and a receiver in a set is approximately 2.5 m, and the transmitters/receivers are mounted approximately 50 mm beneath each plate, ref. Figure 12.

Figure 13 shows in perspective from the front, the unit 30 for moving the packages 2 from rack 1 a to the intermediate storage plates 6. The unit 30 comprises a frame of vertical and horizontal framework 12, and is provided with powered moving devices 8 arranged in spaced vertical relation. The moving devices may be moved by means of motors 13. Pairs of or two neighboring moving devices 8 may be configured in such way that they are powered by the same motor 13.

Figure 14 shows in perspective parts of the unit 20 containing the

intermediate storage devices 6 and the loading station 5 with guiding panels 17,23, including the exit port 19 from the loading station 5, through which the pallet 4 with palletized packages 2 are allowed to exit through. Figure 14 discloses also partly the lift arrangement 40. This arrangement will, however, be described in more details below in connection with Figure 15. As indicated in Figure 14, the guiding and stop panels 23 are configured and mounted in such way that a slot is provided between neighboring panels 23, enabling the plates 6 to be moved into the loading station 5. Figure 15 shows the lifting system 40, where the other parts forming the loading station 5 are deleted from clarity point of view. The lifting arrangement 40 comprises a base 24, configured to support the pallet 4 during the loading operation. The base 24 incorporates a separate roller conveyor in linked with roller conveyors on both side for transport of pallets to the loading station 5 and pallets 4 with packages 2 out of the loading station upon completed palletizing process. The vertical movement of the base 24 is guided at each corner by corresponding vertical guides (not shown) on the frame. The lift arrangement 40 is powered by a motor 25 arranged at the top of the frame through a power transmission 26 and a continuous chain belt 27. At the top and in association with the base 24, pairs of rotatable shafts 28,28' are arranged. Between a pair of vertically spaced apart shafts 28,28' , at each end thereof, vertical endless belts or chains 29 are arranged, one such endless belt or chain 29 being arranged at each corner of the system. When the motor 25 start rotating, the running of the belt or chain 27 will cause the vertical endless belts 29 to move synchronously, lifting or lowering the lift as the case may be.

According to the disclosed embodiment of the present invention, the moving devices are used, of which two and two moving devices 8 are powered by the same motor 13. Moreover, according to the embodiment shown, six intermediate storage plates 6 are used, the bottom plate 6 being in an extended position. The plates are configured to receive the packages 2 from two shelves 9 in a rack 1 a. Using six intermediate storage plates 6 make it possible to store an odd number of layers on a pallet 4, for example 1 1 , 13 or 15 layers if the customer so requires.

It should be noted, however, that the number of plates and moving devices may vary from unit to unit without thereby deviating from the inventive concept. The rack comprises a number of shelves 9 arranged in a vertical stacking. The rack

1 a, 1 b may be used during a cryogenic stage for preservation for example of pelagic fish. For such purpose, the distance between the shelves 9 exceeds the height of the package 2 to be stored, in order to secure adequate freezing. It should be

appreciated, however, that the present invention is not limited to this number of shelves 9, moving devices 8 or plates 6. To the contrary, the present invention may be configured and tailor made to custom specific requirements without deviating from the conceptive idea.

It should be noted that the number of moving devices 8 and intermediate storage plates are dependent on the number of shelves in the rack. If for example the rack has ten or eleven shelves, six intermediate storage plates 6 are used. If for example the rack has twelve or thirteen shelves, seven intermediate storage plates 6 are used. If the rack has fourteen or fifteen shelves, then eight intermediate storage plates 6 are used.

Regarding the electrical automation system according to the present invention, the following should be appreciated:

- On each of the moving devices 8, pushing the packages 2 out of the shelves 9 in the rack 1 a, 1 piece incremental encoder and one piece proximity sensor is used. The encoder is fixed to the driving shaft and gives out pulses, specifying where the moving device 9 at any time is positioned. Increasing counting values when the moving device move forwards towards the rack and decreasing counting values when the moving device 9 returns to its idle, inactive position. The proximity sensor is used for synchronizing the counting from the encoder. The proximity sensor is mounted in such way that it receives signals when the moving device is in its extreme retracted position, away from the rack 1 a.

On each plate it is used one piece incremental encoder and one piece proximity sensor. The encoder is fixed to the driving shaft and sends out pulses, identifying the exact position of the plates at any time. The proximity sensor is used for synchronizing the counting from the encoder. The proximity sensor is mounted in such way that it receives signals when the moving device is in its extreme retracted position, away from the rack 1 a.

- Beneath each plate 6 - approximately 3 to 5 cm - at its rear end, it is placed two sets of through-beam photoelectric sensors arranged in a cross as indicated in the Figure, indicating if any objects or parts of an object is raised up towards the underside surface of plate 6. The purpose of this sensor is to be able to stop the upwards movement of the lift the pallet to correct position below the plate 6, i.e. the position of the top of the pallet, so that the next layer of packages 2 is not pushed off the plate, and/or do not drop to fare down on top of the pallet or top layer on the pallet, such maximum drop height being not more than 3-5 cm, + the thickness of the plate 6, which is in the order of 3 cm.

On the lift, lifting the pallet 4 possibly with packages vertically up and down, one piece incremental encoder and one piece proximity sensor. The encoder is fixed to the driving shaft and sends out pulses, identifying the exact position of the lift at any time. Increasing counting values is given when the lift move upwards and decreasing counting values when the lift moves downwards. The proximity sensor is used for synchronizing the counting from the encoder. The proximity sensor is mounted in such way that it receives signals when the lift is in it lowermost position. In addition one piece of proximity sensor is arranged at the top (top end stop switch) and one piece proximity sensor is arranged at the lowermost end of the lift (lower switch).

For the transport of the pallet into the palletizer to the loading station, a mechanical switch is use, i.e. a movable rod that impart a switching force on a mechanical switch, used for indicating the various pallet positions, i.e. 1 ) a standby position in front of the palletizer unit 10; 2) safety area for entry to the lift; and 3) stop position for pallet on lift.

On the door 19, eight pieces proximity sensors (four pieces on the right hand door blade 19 and four pieces on the left hand door blade 19) are arranged. These proximity sensors indicate the position of the door blades.

Claims

1. A method for palletizing packages (2) stored on shelves in a multi-shelf storage rack (1 a), using a palletizing unit (10) provided with a loading station (5), an unloading station (5), a unit (30) for moving packages (2) on the shelves (9) of the rack (1 a) horizontally from the rack (1 a) towards a position above a pallet (4) and a device (6) for transferring the packages (2) onto the pallet (4); the method comprises placing the multi-shelf rack (1 a) containing packages (2) to be palletized at the unloading station (3); placing the pallet (4) in a loading station (5); moving the packages (2) horizontally from the shelf (9) in the rack (1 a) to a position above the loading position (5); bringing the pallet (4) in position immediately below the packages (2) at the loading station (5) where the packages (2) are placed on the pallet (4); and whereupon the emptied rack (1 b) and the completely palletized pallet (4) eventually are moved away from the unloading station (3) and loading station (5) respectively,

characterized in that the following steps are carried out:

a. moving a number of retractable intermediate storage plates (6) at the loading station (5) horizontally out from a retracted position to an extended position above said pallet (4), the number of plates (6) corresponding to the number of shelves (9) on the rack (1 a) to be palletized in this loading step; b. transferring at least some, preferably all, of the packages (2) horizontally from the shelves (9) in the rack (1 a) onto the intermediate storage plates (6) above the pallet (4) simultaneously by means of the package moving device (8);

c. moving the pallet (4) and/or the lower-most intermediate storage plate (6) close to each other; and

d. repeatedly:

• moving the pallet including the packages (2) and the next lower-most extended intermediate storage plate (6) to a position close to each other,

2. Method according to claim 1 where the emptied rack (1 a) at the unloading space (3) are replaced by a new loaded, next rack (1 b) while palletizing takes place at the loading station (5).

3. Method according to claim 1 , wherein the intermediate shelves (6) are moved down towards the pallet (4) during palletizing.

4. Method according to claim 1 , wherein the pallet (4) is lifted up towards the intermediate shelves (6) during palletizing.

5. Method according to one of the claims 1 to 4, wherein the rack is maintained in a vertical stationary position during the palletizing cycle.

6. Method according to one of the claims 1 to 5, preventing the packages from becoming displaced during the transfer stages, using guiding and stopping means

7. A device for palletizing packages (2) stored on shelves (9) in a storage rack (1 a) to a pallet (4), the palletizing device comprises a loading station (5) for receiving a pallet (4) to be palletized with packages (2) and an unloading station (3) for receiving a multi-shelf rack (1 a) supporting the packages (2), the two stations (3,5) being located adjacent to each other; a unit (30) for moving the packages (2) in the rack horizontally from the shelves (9) of the rack (1 a) to a receiving station vertically above the loading station (5) and a unit (40) for establishing vertical movement between a pallet (4) and the receiving station, characterized by: a. the unit (30) comprises a number of moving means (8), arranged to move some, preferably all, of the packages (2) from shelves (9) of a rack (1 a) simultaneously to a number of retractable intermediate storage plates (6), which is equal to or lower than the number of moving means (8), b. a loading space (5) comprising a lifting unit for moving vertically said pallet (4) to be loaded and the lower-most extended intermediate storage plate close to each other, said loading space (5) being located adjacent said unloading space (3),

c. a second unit comprising said retractable intermediate storage plates (6), said plates being extendable to a position above said pallet (4), and located adjacent said loading space (5), wherein the number of extendable storage plates (6) is equal to or less than the number of shelves in the rack (1 a).

8. Device according to claim 6 where beams are mounted just above the retractable intermediate storage plates (6) retaining the packages (2) on the pallet when the intermediate storage plates (6) retract.

9. Device according to claim 6, wherein the intermediate plates (6) move down towards a stationary pallet (4) during palletizing.

10. Device according to claim 6, wherein the pallet (4) move up towards stationary intermediate plates (6) during palletizing.

11. Device according to any of the claims 6 - 9, wherein the intermediate storage plates (6) move between retracted and extended positions in a horizontal direction parallel to the direction of movement of the moving means (8).

12. Device according to any of the claims 6 - 10, wherein the intermediate storage plates (6) move between a retracted and extended positions in a horizontal direction at a right angle to the direction of the moving means (8).

13. Device according to any of the claims 6 - 1 1 , wherein the number of intermediate storage plates (6) at the loading space (5) equals half the number of shelves in the rack (1 a) providing two layers of packages (2) on each intermediate plate (6).

14. Device according to one of the claims 6 - 13, wherein vertically arranged guiding and stopping devices are arranged along three of the sides forming the loading station, so as to guide and/or prevent packages introduced in the loading station from becoming displaced during the palletizing operation.