BAGGING DEVICE FOR CUTS OF MEAT

Abstract: A bagging device (6) including at least two bag forming means (2, 3) capable of forming bags of a selected variable length from a supply of the material (4) from which the bags are to be formed, transporting means (7, 8, 10) to, in use convey items of differing dimensions to a selected position (5) or to one of a range of available selected positions, sizing means (15) to determine the size of each individual item, and production means to cause in use a bag of desired length to be formed by a selected one of said bag forming means (2, 3).

Description: Bagging device for cuts of meat TECHNICAL FIELD OF THE INVENTION This invention relates to a bagging device and/or a method of bagging and has been devised particularly though not necessarily solely for use in packing cuts of meat. . BACKGROUND ART In a meat works it is necessary to efficiently and effectively bag cuts of meat at an optimum speed. Cuts of meat vary in size and therefore packaging each cut into a bag of the same size leads to wastage of bag material and therefore unnecessary cost, the past a solution to this problem was sought by providing a multiplicity of sizes of bags but this approach led to problems due to the necessity of maintaining substantial stocks of the bags or risk running out of bags of the desired sizes. These problems have been ameliorated to some extent by the provision of bag making machines which form bags from plastic tube material and in which the bag length can be varied depending on the cut that is to be packaged. Such constructions go some way towards overcoming the problem of having correctly sized bags without the necessity of substantial inventory. However there is still some limitation to the flexibility of the constructions having regard to the fixed bag width. OBJECT It is an object of the present invention to provide a bagging device and/or a method of bagging which will obviate or minimise the foregoing disadvantages in a simple yet effective manner or which will at least provide the public with a useful choice. DISCLOSURE OF THE INVENTION Accordingly in one aspect the invention consists in a bagging device including at least two bag fomiing means capable of fomiing bags of a selected variable length from a supply of the material from which the bags are to be formed, transporting means to, in use, convey items of differing dimensions to a selected position or to one of a range of available selected positions, sizing means to determine the size of each individual item, and production means to cause, in use, a bag of the desired length to be formed by a selected one of said bag forming means. Preferably each bag forming means produces bags of a different characteristic. Preferably the differing characteristic is width. Alternatively the differing characteristic is a property of the bag material. Preferably two bag forming means are provided. Preferably said production means causes a bag to be formed when the item is in the selected position. Preferably there is a single selected position. Preferably the transporting means comprise a conveyor. Preferably the sizing means determines the length, breadth and height of the item to be packed. Preferably the sizing means is formed by lasers and cameras to produce a virtual image of the item to be packed, and processor means to in use, cause the selected bag forming means to produce a bag. Preferably the bagging device in use forms bags to package cuts of meat. In a further aspect the invention consists in a method of bagging items of differing sizes, comprising the steps of determining the size of each individual item, forming a bag of a selected length from one of a plurality of bag forming means capable of forming bags of a selected variable length from a supply of the material from which the bags are to be formed so that the bag of selected length is available when the measured item is at the selected position, and transporting each individual item to a selected position. Preferably each bag forming means produces a bag of different width and the step of forming a bag includes the step of determining which bag forming means is to produce the bag having regard to the determined size of the item to be packed. Preferably the item to be packed comprises a cut of meat. To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting. BRIEF DESCRIPTION OF DRAWINGS One prefened form of the invention will now be described with reference to the accompanying drawings in which, Figure 1 is a diagrammatic plan view of a bagging device according to one prefened form of the invention. Figure 2 is a diagrammatic plan view of an alternative bagging device according to one prefened form of the invention, Figure 3 is a diagrammatic representation of a cut-sizing device for use in the invention, Figures 4 to 6 are representations of scanned cuts of meat, and Figure 7 shows a bank of six bag producing means used in the invention. BEST MODE FOR CARRYING OUT THE INVENTION Referring to the drawings, a bagging device is provided which includes a station 1 which includes at least two, and for example up to about eight bag forming means 2 and 3. Each bag fomiing means draws bag forming material such as vacuum shrink material in rolls 4. The rolls 4 may be for example, 1500 metre rolls of tubing from which can be produced vacuum shrink bags on demand. Such bag forming means may be such as described in our patent specification # PCT/EP92/01624 or more desirably our patent specification # PCT/NZ94/00024 or otherwise as desired. The content of those specifications is herein included by reference. Each bag forming means may be mounted in a sliding drawer and each bagging means produces a bag having a differing characteristic, frequently a different width. Other characteristics could include properties of the bag itself, for example, the property may be bags formed of barrier and non-barrier films, or including "bone guard" materials. In a prefened form of the invention, the rolls 4 are each of a different width of tubing material. At the packing station 1 is provided a packing platform 5 adjacent which a packer 6 may stand. In alternative embodiments of the invention several positions 5 could be provided fed by separate conveyor 7, so that the different widths of bag forming means are provided at different stations. This is indicated schematically at 5a and 7a in Figure 1. The prefened embodiment is as described however. A further conveyor 8 is provided to take packed bags away from the packing platform 5. . A main conveyor 10 is provided upon which items such as cuts of meat are placed. A picker 11 picks items from the main conveyor 10 and places them on the branch or pack off conveyor 7. A cut sizing device 15 is provided which may utilise lasers and cameras to determine a three dimensional measurement in particular the breadth, length and height of the item, such as the cut of meat. In the prefened form of the invention the sizer also determines to at least some extent, the contours of the item. From the lasers and cameras is determined an electronic or virtual picture or image of the item and this information is utilised in production means such as a processing device such as a computer to cause in use, a selected bag forming means 2 or 3, for example to produce a bag, in particular, when the measured item reaches the packing station 5. The packing station 5 can be positioned close to the cut sizing device so as to enable the next bag to be produced on the measurement process being completed, or alternatively there can be a gap in which case suitable indexing devices are provided to account for the delay between sizing and packing. This may be achieved by providing a signalling device on each bag forming means, such as a light. By turning on the light on the conect bag forming means, the packer knows which bag to remove and use to pack an item. Once the bag is removed from the bag forming means the light on the bag forming means holding the next required bag is illuminated, and so on. As the bag forming means described in the previously mentioned specifications can form bags at 20 plus per minute, there should be little or no waiting for the next bag. The cut sizer measures in particular the length and width of the cut of meat. The processor then compares these measurements to the available bag widths, selecting the most appropriate width and instructing that bag forming means to provide a bag of the desired length. A signalling device may indicate which bag is to be used. Indexing can be used but in one form assuming it takes 4 seconds to make a bag the cut sizer can be positioned at a position where a cut takes about 4 to 5 seconds to read the bagger 6. Thus when the cut arrives the appropriate bag is available. In one version if the conect bag width is unavailable eg a bag is waiting to be removed then the processor defaults to the next larger bag width. Furthermore as the cut sizer has "seen " each cut as it passes the cut sizing device, the computer can schedule or control the conveyor system so that the product can be fed to the bagging station at a speed the bagging person 6 can handle. As stated above this may be such that a cut arrives about each 4 to 5 seconds. Once the packer 6 has taken the produced bag from bag forming means and inserted the item such as the cut of meat therein, the bag item is placed on the outward conveyor 8 and fed to vacuum packing devices, for example, of the known type. As can be seen in Figure 1 the bag forming means 2 and 3 are placed opposite the bagger 6 with respect to the line of conveyors 7 and 8 and packing platform 5. In Figure 2 an alternative anangement is shown wherein the bag forming means 2 and 3 are placed to some extent in line with the conveyors 7 and 8 and platform 5. The construction works in substantially the same manner except that the position of the bag forming means has been changed. The cut sizing means may include a light which can be a laser device such as a 670mm laser at 60° to the horizontal. A sensor 21 such as CS3 Cam Sensor receives the reflected light. Figures 4 to 6 show printouts of cut meat portions using this cut sizing system. The measuring of the cut of meat at the cut sizer also allows the volume of the cut to be simply calculated. If the specific gravity of the cut is known then an approximate weight of the cut can be achieved. In Figure 7 six baggers 30 to 35 are provided, each having a light 36 to indicate which bagger 30 to 35 the next bag should be taken from. Figure 8 shows an alternative cut sizer which may utilize photocells 40 in a substantially horizontal plane and photocells 42 in a substantially vertical plane by determining which photo cells receive light a number of times as a cut 45 passes along rollers 44 again the cut size can be determined. The sensitivity of photocells available is such that no specific light source need be provided. Thus it can be seen that at least in the prefened form of the invention the bagging device and/or a method of bagging are provided which has the advantage that not only can selected lengths of bags be made, but also by providing multiple bagging bag forming means each carrying a different width of plastics material, a greater flexibility in bag size is achievable. The flexibility is enhanced by the fact that the items to be packaged, such as the cuts of meat, are substantially measured for volumetric size prior to the bagging so that the bagging device can have available to the bagging operator a bag of the conect length and width when the measured item reaches the bagging station. The bag is substantially tailored to the size of the cut to be packed.

Claims: CLAIMS: 1. A bagging device including at least two bag forming means capable of forming bags of a selected variable length from a supply of the material from which the bags are to be formed, transporting means to, in use convey items of differing dimensions to a selected position or to one of a range of available selected positions, sizing means to determine the size of each individual item, and production means to cause in use a bag of the desired length to be formed by a selected one of said bag forming means. 2. A bagging device as claimed in claim 1, wherein each bag forming means produces bags of a different characteristic. 3. A bagging device as claimed in claim 2, wherein the differing characteristic is width. 4. A bagging device as claimed in claim 2, wherein the differing characteristic is a property of the bag material. 5. A bagging device as claimed in claim 1, wherein two bag forming means are provided. 6. A bagging device as claimed in claim 1, wherein said production means causes a bag to be formed when the item is in the selected position. 7. A bagging device as claimed in claim 6, wherein there is a single selected position. 8. A bagging device as claimed in claim 1, wherein the transporting means comprise a conveyor. 9. A bagging device as claimed in claim 1, wherein the sizing means determines the length, breadth and height of the item to be packed. 10. A bagging device as claimed in claim 9, wherein the sizing means is formed by lasers and cameras to produce a virtual image of the item to be packed, and processor means to in use, cause the selected bag forming means to produce a bag. 11. A bagging device as claimed in any one of claims 1 to 10, wherein the bagging device in use forms bags to package cuts of meat. 12. A method of bagging items of differing sizes, comprising the steps of determining the size of each individual item, forming a bag of a selected length from one of a plurality of bag forming means capable of forming bags of a selected variable length from a supply of the material from which the bags are to be formed so that the bag of selected length is available when the measured item is at the selected position, and transporting each individual item to a selected position. 13. A method of bagging as claimed in claim 12, wherein each bag forming means produces a bag of different width and the step of forming a bag includes the step of determining which bag forming means is to produce the bag having regard to the determined size of the item to be packed. 14. A method of bagging as claimed in either claim 12 or claim 13, wherein the item to be packed comprises a cut of meat.

Inventors: MELVILLE RICHARD ARCHER, MELVILLE, RICHARD, ARCHER
Applicants: MACHINERY DEVELOPMENTS LTD, MELVILLE RICHARD ARCHER, MACHINERY DEVELOPMENTS LIMITED, MELVILLE, RICHARD, ARCHER
Application year: 2001
Main classification: B65B43
IPC codes: B65B59