Method and apparatus for producing packed fresh curd blocks

This invention relates to a method for producing packed fresh curd blocks, wherein curd blocks are formed using a plurality of block formers, and said curd blocks are subsequently packed and discharged for further handling. This invention also relates to a cheese production apparatus in which the method can be applied.

The invention is suitable in particular for use in the production of cheddar cheese and similar cheese types. In the production of such cheese types the curd is pre-drained and dried, for instance in a cheddar machine of the type Alfomatic, and the curd thus obtained is so treated that pieces of curd, commonly referred to by the term of (curd) chips, are formed. The chips are fed to the top of a block former column, in which further consolidation and drainage occur. At the lower end of the block former a horizontal blade is disposed, commonly referred to as guillotine blade. The guillotine blade in the rest position closes off the underside of the block former and is retracted at predetermined intervals, so that the pillar of curd situated in the block former can move downwards. While doing so, the pillar of curd is supported by a platform, also moving downwards, which in turn is supported and controlled by a pneumatic cylinder or the like. When the pillar of curd has descended over a predetermined distance, the guillotine blade moves into the rest position again, whereby a block of curd is cut off.

According to the known technique, the blocks are pushed from under the guillotine blade by a push cylinder. In the process, the block passes a guide means, which can be designed as a short horizontal tube of rectangular cross section and which terminates in front of a conveyor track. Arranged at the free end of the tube is a plastic bag of a suitable material, for instance polyethylene. A block so packed in a bag is discharged via the conveyor track, which conventionally comprises a conveyor extending in transverse direction along a number of block formers. The bags are closed and evacuated. The blocks can then be conveyed to a storage room to ripen.

A drawback of the known technique is that the plastic bags at each block former are placed by hand, which is time consuming and unattractive work.

A method according to the preamble of claim 1, and a process according to the preamble of claim 15 are known from the document WO-A-93 22903.

The object of the invention is to obviate the drawback outlined and generally to provide a method and apparatus by means of which blocks produced by a plurality of block formers can be packaged in an efficient, hygienic and reliable manner.

To that end, according to the invention, a method of the above-described type is characterized in that a curd block, after leaving a block former, is placed in a conveying holder, that the conveying holder is conveyed to an automatic packaging apparatus via suitable conveying means, including at least first conveying means, and that the curd block is removed from the conveying holder at the automatic packaging apparatus and is subsequently packed.

A cheese production apparatus comprising a a plurality of block formers and a conveyor passing along the block former(s) is characterized, according to the invention, in that a conveyor track including at least said conveyor leads to a central automatic packaging apparatus, said conveyor track in use conveying conveying holders which in operation receive a curd block in a transfer station at the block former(s) and release such curd block in a removal station at the packaging apparatus.

In the following, the invention is further described with reference to the accompanying drawing.

• Fig. 1 schematically shows in top plan view a part of a cheese production apparatus;
• Figs. 2-5 schematically show a number of successive stages of an example of a method of transferring a curd block from a block former to a conveying holder;
• Figs. 6 and 7 schematically show an example of a method of packaging a curd block in a plastic bag.

Fig. 1 diagrammatically shows in top plan view an example of a part of a cheese production apparatus 1 in which the invention is applied. The cheese production apparatus shown comprises a number of block formers 2, four in the example shown. At the output end or front of each block former a transfer station 3 is arranged, in which the curd blocks produced by the block former are transferred to suitable conveying holders in a manner to be described in more detail below. A conveying holder, while receiving a block, is sitting on a conveyor 4 which at that time is not driven, or which passes under the conveying holder without carrying it along. A suitable conveyor is, for instance, a carrier pawl conveyor, known per se, but other types of conveyors can also be used. For positioning the conveying holders at the proper position and for releasing them for conveyance and for switching the conveyor on and off, if necessary, suitable detectors, known per se, such as, for instance, light barriers and/or proximity switches and the like can be used.

Figs. 2-5 each show a conveying holder 5 disposed on the conveyor 4 in a transfer station 3 in different phases of the transfer of a curd block. Fig. 2 schematically shows the lower portion 6 of a block former and a curd block 7, produced by the block former, which has already been pushed to some extent from under the block former with the aid of means known per se, not shown.

The conveying holder 5 is disposed just under the level of the curd block 7 and has a bottom 8 adapted to move up and down. The bottom 8, in the situation shown in Fig. 2, is in the uppermost position. For moving the bottom 8 up and down, a lift cylinder 9 with a stamp 10 is present, which is disposed under the conveyor track.

The curd block 7 can therefore be pushed onto the bottom disposed in its uppermost position, as indicated by an arrow 11. To prevent damage and/or deformation of the curd block, guide plates 12, of which one is visible, are arranged on opposite sides of the path of the block as viewed in the pushing direction (arrow 11). The guide plates can be stationary or travelling plates. At the forward end, if desired, a travelling plate 13 can be used, so that during displacement the curd block is supported on three sides by guide means. On the fourth side there is a pushing element for displacing the curd block, so that the block is supported on four sides.

When the block is disposed entirely on the lifted bottom 8 of the conveying holder, the bottom 8 can be moved down. The block then descends gradually into the conveying holder and in doing so is guided by the walls of the conveying holder and, insofar as and as long as the block still projects above the conveying holder, by the guide plates.

Fig. 2 further shows the frame 14 of the conveyor track and the pawls 15 of the pawl conveyor used in this example.

Fig. 3 shows in a similar view to Fig. 2 the situation where a curd block 7 descends into a conveying holder 5, as indicated by an arrow 16. In the situation shown in Fig. 4, the bottom 8 is in the lowermost position and the curd block 7 is accommodated entirely within the conveying holder. The conveying holder is now ready to be conveyed to a central packaging apparatus 17 (Fig. 1). Whether the conveyor is in fact switched on at that time, or the conveying holder is released, can depend on the phase the transfer process at other block formers served by the same conveyor is in. According to one possible practical method of operation, before conveyance commences, there is a waiting period until at each block former a filled conveying holder is ready.

The conveyor 4 can, in principle, feed the conveying holder directly to the packaging apparatus 17, but preferably an interposed buffer conveyor 18 is used, which has a buffer function and which connects to the packaging apparatus 17. The buffer conveyor 18 can, for instance, be a conveyor of the chain conveyor type or an apron conveyor.

If desired, it is possible to momentarily press the curd block disposed in the conveying holder. This short pressing step is illustrated in Fig. 5 and can occur in a separate pressing station, not shown in Fig. 1. The pressing station can be provided with a press cylinder 19, as shown in Fig. 5, which is disposed above the conveying holder and which can exert the desired pressing force on the curd block via a pressure plate 20 fitting into the conveying holder and bearing on the curd block 7. Such a pressing step can be desirable, for instance, to increase the stability of the curd block in the case where the curd block is to be cut into smaller pieces prior to packaging. An increase of the stability can also be desirable to prevent deformation of the freshly packaged cheese without using temporary support forms of, for instance, plastic or cardboard. Also, curd blocks which have been produced shortly after a block former has been set into operation or shortly before the end of an operating cycle of a block former can have a lesser stability than the curd blocks produced during the rest of the operating cycle. In those cases too, a pressing step to increase the coherence of a curd block provides advantages.

Optionally, a combination of the transfer station and the pressing station is possible.

Figs. 6 and 7 schematically show a central automatic packaging apparatus 17 with a removal station 21 arranged for removing a curd block from a conveying holder. This can be done by repeating the operations carried out in the transfer stations 3 in substantially reverse order. Fig. 6 schematically shows a frame 24 of the conveyor 18, with a lift cylinder 25 under it, which is provided with a stamp 26 by which the bottom of a conveying holder with a curd block can be moved up. Fig. 6 shows a curd block 7 already moved up in part. It is preferred that the removal station 21, similarly to the transfer stations, be provided with guide means for the curd block. Such a guide means is shown at 27 in Fig. 6 and Fig. 7. Operative between the guide means 27 is a pusher plate 29, operated by a cylinder 28, which can push a curd block over the lifted bottom 8 (Fig. 7) in the direction of a bag opener 30 or wrapper for foil or the like, connecting to the guide means. In Fig. 7 a plastic bag 31 is shown in which the curd block is packaged. Figs. 6 and 7 further show schematically a bag magazine 32 and a discharge conveyor 33. The bag opener 30 and the bag magazine 32 form part of a commercially available automatic packaging machine which further comprises a vacuum and sealing unit, not shown. The thus obtained packaged curd blocks are discharged via a suitable conveyor track 33 to, for instance, a cheese store for further ripening.

The empty conveying holders can be returned to the transfer stations 3 via a return conveyor track 34. Preferably, the return conveyor track first leads the conveying holders through a rinsing tunnel 35 for cleaning the conveying holders.

A major advantage of the use of a central automatic packaging apparatus is that it can process the production of a number of block formers and that it is no longer necessary to arrange packaging material at each block former.

It is noted that after the foregoing, various modifications will readily occur to those skilled in the art. Thus, it is for instance possible to design the block formers in such a manner that the curd blocks descend into the conveying holders directly under the block formers. The conventional platform moving down under a block former is then at the same time the bottom of a conveying holder, also positioned under the block former. In that case, a horizontal push cylinder is not needed.

Further, it is possible to package the curd blocks not in bags but, for instance, in evacuated foil trays, in shrink film or by the so-called flow wrapping technique or the like. These and similar modifications are considered to fall within the framework of the invention.