The invention relates to a food dough extrusion machine comprising a platform and at least one extrusion unit supported by the platform. The invention also relates to a method for changing the functionality of a dough extrusion machine.

DE69923586T2 discloses a moulding device for moulding three-dimensional products from a mass of foodstuff. The moulding device comprises a mould having a mould cavity with a fill- ing opening for filling the cavity with a portion of the mass. A closure means closes the filling opening of the mould cavity, so that the mass is held in the closed mould cavity for a fixing period after which the mould cavity is opened and the moulded product is removed. The moulding device may be a drum rotatable around a horizontal axis and comprising along its circumference a plurality of moulds.

DE7118662U discloses a device for depositing dough on a carrier. The pressing action for pressing dough through outlet openings has to be provided by an operator by means of a lever system. Extrusion machines according to prior art are inflexible. The change of functionality, particularly the adaption to different food qualities is usually not possible or very difficult. Usually different extrusion machines are necessary in order to process different dough qualities.

Accordingly, it is an object of the invention to provide an improved dough extrusion machine for food industry. In particular, the dough extrusion machine shall allow for high flexibility or adjustability as well as for easily changing the functionality. Handling, exchange and cleaning of parts coming into contact with dough should be simplified. Furthermore, assembling and servicing shall be performed at lower costs and in shorter time. The problem of the invention is solved by a dough extrusion machine as defined in the opening paragraph, in that the extrusion machine has a guidance by which the at least one extrusion unit is supported on the platform and by which the at least one extrusion unit is adjustable relative to the platform and/or removable from the platform. The invention facilitates adjustment, (re)moving and/or exchange of the extrusion unit. The guidance not only allows correct adjustment of the extrusion unit prior or during operation, but also allows to completely remove the extrusion unit by means of the guidance.

The invention relates to a food dough extrusion machine, particularly for producing bakery products, such as biscuits, cookies, crackers, etc. The term "dough" has a broad meaning within the sense of the present application and comprises any flowable food masses or kneaded food material, including fillings, creams, paste-like material, and may contain cereals (particularly wheat), sugar, salt, milk, eggs, bakery improvers, chocolate, nougat, nuts and/or other ingredients.

Platform may be any kind of support supporting the extrusion units, particularly a table, a frame, a base, etc., preferably with an integrated conveyor for transporting extruded dough.

The extrusion unit has of course a plurality of outlet nozzles through which the dough flow (extruded dough) is discharged, e.g. onto a conveyor.

In a preferred embodiment the extrusion unit is supported on the platform by means of rolls which are rollable along the guidance. This reduces friction during movement. Preferably, the rolls are mounted to the upper part of the extrusion unit.

Preferably, each roll is covered by a protective cover moving along with the respective roll. In such a way the rolls are protected from dough, dirt and external impacts.

In a preferred embodiment the guidance is provided on the platform and the rolls are mounted to the extrusion unit. Here, the guidance is stationary with respect to the platform.

In a preferred embodiment the guidance comprises at least two parallel rails, allowing a stable and well-defined support of the extrusion unit.

In a preferred embodiment the extrusion unit has a lower part and an upper part, wherein the lower part is detachable from the upper part, wherein the distance between the rails is larger than the width of the lower part. Width is the extension of the extrusion unit in a direction perpendicular to the rails. Here, the lower part may be lowered through the area between the rails or rails of a corresponding carrier (see below). In a preferred embodiment the lower part comprises a functional insert for conducting dough, preferably a pump and/or a filler block and/or a nozzle arrangement. By exchanging only the lower part or only the functional insert (the upper part stay the same) the functionality of the extrusion machine may be changed in an quick and elegant way. In the case of a pump the functional insert may comprise structured rolls pumping the dough towards the outlet nozzles. A filler block is a passive element forming at least one, preferably a plurality channels for conducting dough from the feed rollers of the extrusion unit to the outlet nozzles.

Preferably, the extrusion unit comprises at least one feed roller, preferably (at least two) feed rollers, wherein preferably the at least one feed roller is accommodated in the upper part of the extrusion unit. The feed roller(s) is/are rotatably mounted within the extrusion unit and connected to a drive. The feed roller(s) force(s) dough from the dough supplying means (hopper) towards the outlet (nozzles).

The upper part of the extrusion unit may further comprise a hopper or any other suitable dough supplying means. It is preferred that the upper part of the extrusion unit comprises two feeding rollers forming a gap for transferring the dough towards the outlet nozzles. Downstream of the feeding rollers and upstream of the outlet nozzles the lower part comprises a functional unit such as a pump housing (e.g. comprising structured rolls) or a filler block. Preferably, the extrusion unit has a guidance by which the dough supplying means is movea- bly supported, preferably by means of rolls which are reliable along the guidance, wherein preferably the guidance supporting the dough supplying means is essentially parallel to the guidance supporting the extrusion unit. This allows adjustment of the dough supplying means (hopper) prior or during operation.

In a preferred embodiment the lower part comprises a frame to which the functional insert is detachably mounted. Here, only the insert may be exchanged. Preferably, the lower part is detachable from the upper part in a downward direction. This allows an ease removal of the lower part, particularly on an external carrier system. Particularly, the lower part may be lowered through an area between the rails of the guidance. Preferably, the lower part is attached to the upper part by fastening means, preferably by screws, wherein the fastening means is accessible from the top or the side of the extrusion unit and/or comprises a quick release mechanism. This allows for good accessibility and simple removal of the lower part. In a preferred embodiment the extrusion unit is detachably coupled to a drive unit for driving a functional insert in the lower part of the extrusion unit and/or feed rollers accommodated in the upper part of the extrusion unit. By moving the extrusion unit along the guidance it may be removed from the driving unit. The driving unit may be stationary with respect to the guidance. This embodiment is preferred since the extrusion unit may be easily removed from the platform without the driving unit. The driving unit may comprise a drive for feed rollers accommodated in the upper part of the extrusion unit and a drive for the functional unit in the lower part of the extrusion unit, such as a pump.

In a preferred embodiment the platform comprises a conveyor (e.g. belt) for transporting dough extruded by the extrusion unit, wherein the guidance extends above the conveyor, preferably transverse, more preferred essentially perpendicular to the transporting direction of the conveyor. Here, the guidance forms a bridge over the conveyor. It is preferred that the extrusion unit has longitudinal extension and extends transverse to the transporting direction of the conveyor. The outlet nozzles of the extrusion unit are arranged along the longitudinal direc- tion of the extrusion unit.

In a preferred embodiment the dough extrusion machine comprises a carrier system for temporarily supporting an extrusion unit, wherein the carrier system comprises a first carrier having a guidance, preferably in form of two parallel rails, wherein the guidance may be brought into alignment with the guidance formed on the platform, such that the extrusion unit may be moved along the guidances from the platform to the first carrier and vice versa. By aligning the guidance of the platform and the guidance of the first carrier the extrusion unit may easily transferred from the platform to the carrier system. On the carrier system the functionality of the extrusion unit may be changed, e.g. by exchanging the lower part of the extrusion unit.

In a preferred embodiment the carrier system comprises a second carrier that may be lowered with respect to the first carrier. The second carrier may be arranged below or within the first carrier for supporting and lowering the lower part of the extrusion unit, while the upper part is held by the first carrier.

In a preferred embodiment the first carrier and/or the second carrier has/have rolls by which the first carrier and/or the second carrier are movable relative to the platform. This allows cleaning, servicing and/or changing functionality of the extrusion unit apart from the platform.

The problem is also solved by a method for changing the functionality of a dough extrusion machine, comprising the steps of: (a) removing the extrusion unit from the platform and (b) exchanging a functional insert of the extrusion unit and (c) moving the extrusion unit to the platform (again).

In a preferred embodiment during step (a) the extrusion unit is moved along the guidances from the platform to the first carrier of the carrier system and wherein step (b) is performed on the carrier system.

In a preferred embodiment the extrusion unit has a lower part and an upper part, wherein the lower part is detachable from the upper part, and wherein the carrier system comprises a sec- ond carrier that may be lowered with respect to the first carrier, and wherein the lower part of the carrier is lowered by the second carrier.

In a preferred embodiment the first carrier has two rails and wherein the lower part of the extrusion unit is lowered through the area between the rails of the first carrier.

For a better understanding of the invention the latter is explained in more detail with reference to the following Figures.

Fig. 1 shows a dough extrusion machine according to the invention, Fig. 2 shows the dough extrusion machine with a carrier system,

Fig. 3 shows the carrier system comprising a first carrier and a second carrier,

Fig. 4 shows the carrier system with lowered second carrier,

Fig. 5 shows the frame of the lower part of the extrusion unit,

Fig. 6 shows the frame with a filler block,

Fig. 7 shows the frame with a pump housing,

Fig. 8 shows in a cross sectional view the extrusion unit having a filler block,

Fig. 9 shows in a cross sectional view the extrusion unit having a pump. Generally, the same parts or similar parts are denoted with the same/similar names and reference signs. The features disclosed in the description apply to parts with the same/similar names respectively reference signs. Indicating the orientation and relative position (up, down, sideward, etc.) is related to the associated Figure, and indication of the orientation and/or relative position has to be amended in different Figures accordingly as the case may be.

Fig. 1 shows a food dough extrusion machine 10 comprising a platform 2 and an extrusion unit 1 supported by the platform 2. The extrusion machine 10 has a guidance 3 by which the at least one extrusion unit 10 is supported on the platform 2 and by which the at least one extrusion unit 10 is adjustable relative to the platform 2 and/or removable from the platform 2 (Fig. 2).

The extrusion unit 1 is supported on the platform 2 by means of rolls 6 which are reliable along the guidance 3 which comprises at least two parallel rails 4, 5. Each roll 6 may be covered by a protective cover moving along with the respective roll 6 (Fig. 1).

The platform 2 also comprises a conveyor 20 (in form of a transporting belt) for transporting dough extruded by the extrusion unit 1, wherein the guidance 3 extends above the conveyor 20, preferably transverse, more preferred essentially perpendicular to the transporting direction 21 of the conveyor 20.

The extrusion unit 1 has a lower part 8 for accommodating a functional insert 9 and an upper part 7 accommodating feed rollers 27 (Figs. 8 and 9) for feeding dough from the hopper 11 to the functional insert 9. The functional insert 9 conducts dough towards outlet nozzles 18. The functional insert 9 may be a pump 16 e.g. in form of a pump housing (Fig. 9) or a filler block 17 (Fig. 8) and may also comprise the outlet nozzle arrangement 18. While the pump actively forces dough towards the outlet nozzles 18, the filler block 17 is a passive element e.g. comprising a plurality of channels leading towards the outlet nozzles 18. It depends on dough quality (weight, density, flow characteristic) which functional insert is best used. The extrusion unit of Fig. 8 has thus a different functionality than the extrusion unit of Fig. 9.

As can be seen from Fig. 1 the extrusion unit 1 has a guidance by which the hopper 11 is moveably supported by means of rolls which are rollable along the guidance. The guidance supporting the hopper 11 is essentially parallel to the guidance 3 supporting the extrusion unit 1.

As can be seen from Fig. 2 the extrusion unit 1 is detachably coupled to a drive unit 12 for driving a functional insert 9 in the lower part 8 of the extrusion unit 1 and the feed rollers 27 accommodated in the upper part 7 of the extrusion unit 1. Here, the drive unit 12 is mounted to the guidance 3.

Fig. 2 shows a carrier system 22 for temporarily supporting an extrusion unit 1, wherein the carrier system 22 comprises a first carrier 23 having a guidance 13 in form of two parallel rails 14, 15, wherein the guidance 13 may be brought into alignment with the guidance 3 formed on the platform 2. In this alignment the extrusion unit 1 may be moved along the guidances 3, 13 from the platform 2 to the first carrier 23 and vice versa.

Fig. 3 and 4 show that the carrier system 22 comprises also a second carrier 24 that may be lowered with respect to the first carrier 23. With the second carrier 24 the lower part 8 of the extrusion unit 1 may be lowered and removed/exchanged (Fig. 4). The second carrier 24 has a scissor-type lowering mechanism. The lower part 8 of the extrusion unit 1 is detachable from the upper part 7 (by removing screws 28 in Fig. 3), wherein the distance between the rails 4, 5 and 14, 15 is larger than the width of the lower part 8, such that the lower part 8 may be low- ered through the area between the rails 14, 15.

The first carrier 23 and the second carrier 24 have rolls 25, 26 by which they are movable relative to the platform 2. The lower part 8 comprises a frame 19 to which the functional insert 9 is detachably mounted (Fig. 5, 6 and 7). In Fig. 6 a filler block 17 with a nozzle arrangement 18 is inserted in the frame 19. In Fig. 7 a pump 16 (housing) with a nozzle arrangement 18 is inserted in the frame 19. In order to change the functionality of the extrusion unit 1, the lower part 8 is removed and exchanged as a whole or only the functional insert 9 is exchanged and the same frame 19 is used again.

As can be seen from Fig. 3 and 4 the lower part 8 is detachable from the upper part 7 in a downward direction.

The method for changing the functionality of a dough extrusion machine 10 comprises the steps of: (a) removing the extrusion unit 1 from the platform 2 (see Fig. 2) and (b) exchanging a functional insert 9 of the extrusion unit 1 (Fig. 3 and 4) and (c) moving the extrusion unit 1 with the exchanged functional insert 9 to the platform 2.

Removing or exchanging the functional insert 9 is done by means of the carrier system 22. The first carrier 23 supports the upper part 7 of the extrusion unit 1, while the second carrier 24 supports the lower part 8 and is lowered with respect to the first carrier 23. The second car- rier 24 may be - independently of the first carrier 23 - moved to a different place and a new/different lower part or only a new/different functional insert may be arranged to the second carrier 24 in order to be joined with the upper part (waiting on the first carrier 23) again.

In the step shown in Fig. 3 and 4 the lower part 8 of the extrusion unit 1 is lowered through the area between the rails 14, 15.

It is noted that the invention is not limited to the embodiments disclosed hereinbefore, but combinations of the different variants are possible. In reality, the dough extrusion machine may have more or less parts than shown in the Figures. The machine and parts thereof may also be shown in different scales and may be bigger or smaller than depicted. Finally, the description may comprise subject matter of further independent inventions. List of reference signs extrusion unit

platform

guidance

rail

rail

rolls

upper part

lower part

functional insert

frame

hopper

drive unit

guidance

rail

rail

pump

filler block

nozzle arrangement

frame

conveyor

transporting direction

carrier system

first carrier

second carrier

rolls

rolls

feed roller

screws