EP3849320A1

EP3849320A1 - Pressure-controlled dough-rounding device

Info

Publication number: EP3849320A1
Application number: EP19772973.4A
Authority: EP
Inventors: Eduard Rauch; Hannes STELZER
Original assignee: Koenig Maschinen GmbH; Konig Maschinen GmbH
Current assignee: Koenig Maschinen GmbH; Konig Maschinen GmbH
Priority date: 2018-09-11
Filing date: 2019-09-11
Publication date: 2021-07-21
Also published as: US20220039400A1; WO2020051613A1; AT521634B1; CA3112431A1; AT521634A1

Abstract

The invention relates to a working system (100) for working pieces of dough (5), comprising: at least one working cup (3), each working cup having an opening (31), a receiving space (32) for receiving pieces of dough (5) and a working insert (4), the working insert (4) delimiting the receiving space (32) on the side of the receiving space remote from the opening (31); an abutment (1), which is arranged opposite the opening (31) of the working cup (3); a height adjustment device (17), which is designed to reversibly, in particular mechanically, electromechanically, pneumatically or hydraulically, move the at least one working cup (3) from a starting position remote from the abutment (1) to a working position near the abutment (1); and a drive unit (18), which is designed to set the at least one working cup (3) into oscillating motion, wherein: each of the at least one working cups (3) has a pressure cylinder (7) having a pressure piston (71) that can move in the pressure cylinder; a pressure control unit (20) is provided; the pressure control unit (20) is pressure-transmittingly connected to the pressure cylinder (7); the pressure control unit (20) is designed to apply a variable pressure and/or volume to the pressure cylinder (7); and the pressure piston (71) is pressure-transmittingly connected to the working insert (4) in such a way that the force on the working insert (4) can be changed when the pressure in the pressure cylinder (7) and/or the pressure characteristic curve of the pressure control unit (20) changes.

Description

PRESSURE CONTROLLED DOUGH MAKING DEVICE

The invention relates to a knitting plant for knitting dough pieces according to the preamble of claim 1 and a dough processing plant according to claim 1 1.

A large number of knitting devices are known from the prior art, which are used for the production of various types of baked goods. The known knitting devices have in common that they comprise knitting cups in which dough pieces, which rest on an abutment, are received for knitting. Known knitting cups of this type are usually equipped with a knitting insert, the surface of which is in targeted contact with the pre-portioned dough piece. The knitting cup is used to oscillate the dough pieces.

The variety of products and the quality requirements for pastries are subject to constant increase. In order to increase the quality and to meet trends such as organic pastries or pastries that are produced without the addition of certain food additives, etc., baking aids are increasingly being omitted, which means that such doughs are “long-term managed” and made from organic raw materials . As a result, it is necessary to adapt the production systems to these requirements or to provide them with maximum flexibility. These doughs are associated with significantly higher requirements over the entire production process, since these differ essentially in terms of "machine compatibility" from doughs with auxiliary substances. In addition, the dough changes its nature or its behavior more quickly during the processing process. It is therefore necessary to follow the knitting process of doughs with high kettle cooking, in the technical jargon "long-term management", or doughs with a high proportion of fermentation bladders as close as possible to the manual knitting process In the manual knitting process, the dough piece is initially pressed against the surface, then the knockout begins, in the course of the spherical formation the hand reduces the pressure and gives the space or the height for the desired hte ball formation free. Different processing pressures or characteristic curves of the pressure curves are therefore required to process different doughs in order to implement the manual molding process automatically. In the known devices, springs are used to produce the required pressures. Furthermore, it is known to effect the retraction movement mechanically, for example by means of cams or electromechanically. However, these known methods are not sufficient for long-term doughs and the associated quality requirements. Systems with springs basically have an inverse characteristic curve for these processes, which is too little during the “action” of the dough piece, during which there is contact between the knitted nest and the dough piece, and / or too high during the formation of a ball from the dough piece Exerts pressure, which does not meet the requirements of long-term dough. Mechanical or electromechanical systems work according to a specification which must or should be permanently regulated according to the types of dough and the maturity of these doughs, which means a great deal of effort.

Furthermore, a higher pressure is required at the beginning of the knitting process to press the dough pieces against the abutment and into the knitting nests, so that the dough pieces are fixed in the knitting nests for a short time. At the beginning of the knitting process, the formation into a spherical shape begins; the flat dough piece increases in height up to the complete ball. This means that the knitted cup "gives way" by the required height. Solid or green doughs require higher pressure and a steep characteristic, while soft and / or gas-containing doughs require low to no pressure and a very flat characteristic. The core voltage is also directly related to the characteristic.

Initially, high pressure results in a fixed core tension, while lower pressure results in a slight core tension. The desired core tension forms the prerequisite for the following further processing or shaping. If flat pastries are desired, the core tension is kept lower than if the pastries are to be high and crowned, i.e. should show a good standing or training. In this case, a fixed core voltage is required.

The object of the invention is therefore to remedy this situation and to provide a knitting system which makes it possible to use different kneading pressures and kneading pressure characteristics for dough pieces of different types of dough during the knitting, and to emulate the manual processes in the best possible way.

The invention solves this problem in a knitting plant for knitting dough pieces with the characterizing features of claim 1. Such a knitting plant comprises at least one knitting cup, each having an opening, a receiving space for receiving dough pieces and a knitting insert, the knitting insert delimiting the receiving space on its side facing away from the opening,

an abutment which is arranged opposite the opening of the knuckle cup, a height adjustment device which is designed to reversibly, in particular mechanically, electromechanically, pneumatically or hydraulically, the at least one knuckle cup from a starting position remote from the abutment to a knocking position close to the abutment adjust, and

- A drive unit, which is designed to set the at least one knitting cup in an oscillating movement.

According to the invention, the at least one knitted cup each has a pressure cylinder with a pressure piston movable therein, and a pressure control unit is provided, which is connected to the pressure cylinder in a pressure-transmitting manner. The pressure control unit is designed to apply a variable pressure and / or volume to the pressure cylinder. The pressure piston is in each case connected in a pressure-transmitting manner to the active insert in such a way that when the pressure in the pressure cylinder and / or the pressure characteristic curve of the pressure control unit changes, the force acting on the active insert can be changed.

The printing system has, for example, a memory with a variable volume. By changing the pressure, the pressure can be adjusted when "acting", while by changing the volume in the pressure accumulator the angle of the characteristic curve is regulated. Green doughs require steep, long-cooked doughs with a flat characteristic.

This configuration of the invention ensures that the effective pressure when the manual is applied corresponds to the characteristic curve for dough pieces according to the piece weight and defined size, which can be optimally adjusted depending on the proportion of fermentation bubbles and thus the density of the dough piece, without, for example, the active cups or effective inserts of the active system need to replace. In the following, the term "knitting" means the round knitting, but also the long knitting of dough pieces.

The pressure control unit can be used to change or control the pressure exerted on the dough pieces in the knitting process via the knitting inserts, so that changes in dough consistency resulting during the processing or knitting of the dough pieces can be taken into account directly by changes in the pressure acting on the knitting pieces and in the pressure characteristic curve . A particularly good adaptation of the pressure to different types of dough or dough consistency can be achieved if the pressure control unit is designed to apply a predetermined, constant pressure to the pressure cylinder or a pressure corresponding to at least one predetermined, in particular linear or variable, pressure characteristic , so that the pressure acting on the active insert and the pressure characteristic are adjustable.

For example, it is possible to optimize the effective pressure for dough pieces of a certain type of dough using e.g. to generate a pump and transfer it to the respective dough piece via the active insert. If dough pieces of another type of dough are introduced into the knitting machine for knitting, the knitting pressure can be reduced or increased accordingly without having to replace the knitting cups or knitting inserts. In a particularly simple embodiment variant of the invention, with which a pressure which is variable during the knitting process can be exerted on the knitting cups according to a predetermined pressure characteristic curve, it can be provided that the pressure control unit has a first pressure generating unit and a second

Pressure generation unit, wherein the first pressure generation unit and the second pressure generation unit are each pressure-transmitting connected to a pressure transmission unit and are designed such that a pressure can be set in the pressure transmission unit according to at least one predetermined, in particular linear or variable, pressure characteristic curve, and wherein the pressure transmission unit pressure-transmitting is connected to the impression cylinder.

In this context, the pressure characteristic is understood to mean the pressure-volume flow characteristic. This means that the pressure generated by the pressure control unit, which is transmitted to the active insert via the pressure cylinder or the pressure piston, increases when the fluid volume delivered per unit of time increases.

A particularly efficient setting of various pressure characteristics can be achieved if the pressure transmission unit is designed as a piston accumulator, that is to say as a hydropneumatic pressure accumulator.

the piston accumulator has a hydraulic chamber, in particular filled with hydraulic fluid, a pneumatic chamber, in particular filled with gas, and a piston arranged between the hydraulic chamber and the pneumatic chamber, the first pressure generating unit, in particular a compressor, being connected to the pneumatic chamber in a pressure-transmitting manner,

the second pressure generating unit, in particular a hydraulic pump, is connected to the hydraulic chamber in a pressure-transmitting manner,

- A pressure corresponding to at least one predetermined, in particular linear or variable, pressure characteristic curve can be set in the piston accumulator by pressurizing the hydraulic chamber, and

- The piston accumulator is designed to change the pressure and / or the volume in the pressure cylinder.

By using a piston accumulator, high volume flows can advantageously be provided at short notice and large amounts of energy can be stored with a small internal volume. A particularly rapid change in the pressure characteristic curves, especially with high outputs or high throughput of the active system, can be achieved if the pressure control unit comprises at least one pump and a number of pressure accumulators.

the at least one pump is connected to the pressure cylinder via a pressure line,

- The pressure accumulators can each be connected to the pressure line via valves and each have a predetermined, in particular linear or variable, pressure characteristic curve, and

- The pressure control unit is designed, in particular by opening and / or closing the valves, to apply pressure to the pressure cylinder of the at least one kneading cup in each case in accordance with a pressure characteristic curve, in particular linear or variable, resulting from the pressure characteristic curves of the pressure accumulators. In a technically and energetically particularly efficient performance, the pressure control system comprises two pressure accumulators and a reversible pump system similar to an ABS in vehicle technology. The pressure and the pressure characteristic can be reached with just one pump and two shut-off valves and the control reacts quickly enough to achieve high cycle rates of up to 100 / min, which requires a minimum of energy. For a particularly efficient action of dough pieces, it can be provided that the active insert is designed to transmit the pressure transmitted from the pressure piston to the active insert as a force acting orthogonally to the abutment. In order to further optimize the action of dough pieces, while at the same time ensuring that the entire surface of the dough pieces is exposed to an ideal effective pressure, so that the surface increases and the core tension of the dough pieces is improved, it can be provided that the abutment has at least one, in particular in Form of one or more recesses, knitted nest for fixing the dough pieces on the abutment, wherein in particular it is provided that the knitted nest is each formed from a number of concentric recessed grooves.

The knitted nests are formed, for example, as one or more recesses in the surface of the abutment or the conveyor belt running on the abutment, which make a targeted contact with the pre-portioned dough piece, so that the dough piece is efficiently knitted. The knitted nests can be formed, for example, from a plurality of parallel or concentric grooves.

In order not to damage the dough piece during the knitting or to damage its surface or fluff, it can be provided that a knitting gap is formed between the knitting cup and the abutment in the knitting position.

In order to efficiently design knitting plants or knitting cups and knitting inserts for different types of dough or dough qualities, it can be provided that

- The active insert has a smooth or structured surface and / or

- The receiving space has a curved or semicircular cross section and / or a round or oval projection surface.

A particularly effective adaptation of the differential pressure or the pressure characteristic to different types of dough can be achieved if the pressure characteristic can be set by the pressure control unit according to the dough rheology and / or the initial shape of the dough pieces. For this purpose, it can be provided, for example, that the rheological properties of the dough to be processed are determined during processing, for example at predetermined time intervals, and the pressure characteristic curve or the pressurization of the active insert are adapted in accordance with the properties determined in this way. The invention further relates to a dough processing system for processing dough strips comprising a knitting system according to the invention, the abutment having a takeover side for taking over, in particular pre-portioned, unprocessed dough pieces and a transfer side for transferring knitted dough pieces. The dough processing system further comprises at least one transport device which is designed to transfer in particular pre-portioned, unprocessed dough pieces to the transfer side of the abutment to the abutment and / or to take knitted dough pieces on the transfer side of the abutment from the abutment.

With this design of a dough processing system, it is possible to set optimal, variable effective pressures for the dough pieces during the automatic processing of dough bands that are cut into portions or dough pieces according to weight and / or volume.

Further advantages and refinements of the invention result from the description and the accompanying drawings.

In the following, the invention is shown schematically in the drawings on the basis of particularly advantageous but not restrictive exemplary embodiments and is described by way of example with reference to the drawings.

Show below:

1 shows schematically two knitted cups and an abutment of a knitting plant according to the invention,

2a schematically, the action of a dough,

2b schematically shows a flow diagram of a knitting process,

2c schematically the beginning of the knitting process,

2d schematically shows the end of the knitting process,

2e a section of an abutment with a knitting nest in cross section,

2f shows a detail from a top view of an abutment with four knitting nests according to FIG. 2e,

3a shows a sectional view of a knitting cup of a knitting plant according to the invention in knitting position before the knitting process begins,

3b shows a first sectional view of the knitting cup in knitting position during the knitting process, 3c shows a second sectional view of the knitting cup in knitting position during the knitting process,

3d shows a sectional view of the knitted cup in the starting position with a knitted dough piece,

4a is a sectional view through a knitted cup without pressurization by the pressure control unit,

4b is a sectional view through the knitted cup when pressurized,

5 schematically shows a sectional view through two knitted cups when pressurized by a combined hydraulic-pneumatic pressure control unit,

6 is a sectional view through an active cup when pressurized by a hydraulic pressure control unit,

Fig. 7 is a schematic representation of a sectional view through an active system according to the invention and

Fig. 8 is a schematic representation of a sectional view through an active cup when pressurized by a pressure control unit with two buffer stores.

FIG. 7 schematically shows a sectional view through a first exemplary embodiment of a knitting plant 100 according to the invention for knitting dough pieces 5. In the exemplary embodiment shown, the knitting plant 100 comprises a plurality of rows of five knitting cups 3 arranged next to one another, each having an opening 31 and a receiving space 32 for receiving dough pieces 5. The receiving space 32 of each knitting cup 3 is delimited by a knitting insert 4 on its side facing away from the opening 31. The knitting unit 100 further comprises an abutment 1, which is arranged opposite the opening 31 of the knitting cups 3. In the embodiment shown, the abutment 1 is a conveyor belt on which the dough pieces 5 are transported. In the exemplary embodiment shown, the knitting system 100 also has a height adjustment device 17, e.g. mechanical or hydraulic adjustment or an electric lifting column, which adjusts the active cup 3 from an initial position remote from the abutment 1 to an active position close to the abutment 1.

The dough pieces 5 are transported for knitting on the abutment 1 into the area of the knitting cups 3 and the height adjustment device 17 lowers the knitting cups from the starting position into the knitting position, so that the dough pieces 5 are received through the opening 31 in the receiving space 32 of the knitting cups 3 ( see Fig. 3a, 3b, 3c). There is an active gap 6 between the wall of the active cup 3 and the Release opponent 1 so as not to damage the dough piece 5 during the working.

The cross section of the receiving space 32 has a curved shape in the exemplary embodiment shown, but can alternatively also have a semicircular shape, for example. The projection surface of the receiving space 32, that is to say that surface which is delimited by the receiving space 32 in a plan view, has a round shape in the exemplary embodiment shown, but can optionally also be oval, for example.

In the exemplary embodiment shown, the knitting insert 4 each has a smooth surface to ensure that the dough does not adhere to the knitting insert 4 and the surface of the dough piece 5 is not damaged. Alternatively, the knitting insert 4 can also have a structured surface, for example for knitting solid types of dough.

Furthermore, the knitting unit 100 has a drive unit 18 which is designed to set the knitting cups 3 in an oscillating movement. In the exemplary embodiment shown, the drive unit 18 comprises a motor, which is connected via gear elements such as belts to two knitting eccentrics, which determine the deflection of the oscillating movement that the knitting cups 3 perform while the dough pieces 5 are kneading.

The knitting cups 3 of the knitting system 100 each comprise a pressure cylinder 7 with a pressure piston 71 movable therein, which are shown in detail, for example, in FIGS. 2a, 4a and 4b. Furthermore, the knitting system 100 comprises a pressure control unit 20, which is connected in a pressure-transmitting manner to the pressure cylinder 7 of each knitting cup 3, whereby a pressure in the pressure cylinder 7 is also transmitted to the pressure piston 71. The pressure piston 71 is in turn connected to the active insert 4 of each pressure cup 3 in a pressure-transmitting manner. Thus, when the pressure cylinder 7 is acted upon by the pressure control unit 20, for example with an increasing pressure and / or volume, the pressure piston 71 acts on the active insert 4 with an increasing pressure, which acts on the dough piece 5 from the active insert 4 as a force orthogonal to the abutment 1 is transmitted. When the pressure in the pressure cylinder 7 drops, the pressure piston 71 reduces the pressure acting on the active insert 4 and the force acting on the dough piece 5 is also reduced. As already described above, when processing a wide variety of products or a wide variety of dough consistencies and recipes, it is advantageous to also vary the force acting on the dough pieces 5 during the knitting process, since the knitting pressure is decisive for the formation of the surface, the core tension and the active lock on the dough pieces 5 influenced. In a knitting system 100 according to the invention with a pressure control unit 20, it is thus advantageously possible to vary the pressure acting on the knitting insert 4 via the pressure cylinder 7 or the pressure piston 71 during the knitting process, so that the dough or the dough respectively processed during the entire knitting process the respective dough consistency ideal pressure force can be exerted on the dough piece 5 and thus an optimal action of the dough pieces 5 is ensured.

Examples of pressure control units 20 according to the invention are shown in detail in FIGS. 4a, 4b, 5 and 6. 4a shows a sectional view through an active cup 3 of an active system 100 according to the invention, which is in the active position. This means that the active cup 3 is arranged close to the abutment 1 and an active gap 6 is formed between the active cup 3 and the abutment 1. In the exemplary embodiment shown there is a dough piece 5 on the abutment 1 which is to be knitted. The knitted cup 3 has a pressure cylinder 7 and a pressure piston 71, the pressure cylinder 7 being connected to the pressure control unit 20 via a pressure line 21. Such a simply designed pressure control unit 20 can be, for example, a hydraulic pump or pneumatic system that can be connected to the pressure line 21. The active insert 4 is in turn connected to the pressure piston 71 in a force-transmitting manner. As can be seen in FIG. 4 a, the pressure chamber 7 is empty, so that it is not pressurized, no pressure is applied to the pressure piston 71 and therefore no force is transmitted from the active insert 4. If this is the case, the position of the knitting insert 4 or its distance in the direction of the abutment 1 is set freely in the knitting cup 3 depending on the fleas of the dough piece 5.

4b shows a sectional view through an active cup 3 in the active position WP, in which the pressure chamber 7 is pressurized by the pressure control unit 20 via the pressure line 21. In this case, the pressure control unit 20 is designed to apply a predetermined constant pressure or a pressure corresponding to at least one predetermined pressure characteristic curve to the pressure cylinder 7. As can be seen in FIG. 4 b, the pressure piston 71 transmits the pressure present in the pressure cylinder 7 to the knitting insert 4, so that it moves in the direction of the abutment 1 or in the direction of the dough piece 5 and correspondingly that of the pressure control unit 20 in the pressure chamber 7 Set pressure exerts a defined force on the dough piece 5.

FIG. 5 shows a further section from an active system 100 according to the invention, in which the pressure force acting on the active inserts 4 can be adjusted via a combined hydraulic-pneumatic pressure control unit 20. In the exemplary embodiment shown, the printing unit 20 comprises a first pressure generating unit 8 and a second pressure generating unit 10, which are each connected to two chambers of a pressure transmission unit 11 in a pressure-transmitting manner.

The pressure transmission unit 11 is in turn connected via a pressure line 21 in a pressure-transmitting manner to the pressure cylinder 7 of each active cup 3. In the exemplary embodiment shown, the pressure transmission unit 11 is a piston accumulator which has a fly hydraulic chamber 12a and a pneumatic chamber 12b. The flydraulic chamber 12a is filled with hydraulic fluid in the exemplary embodiment, while the pneumatic chamber 12b is filled with gas or air. The piston accumulator further comprises a piston 13 which is movably arranged in the piston accumulator and which separates the hydraulic chamber 12a from the pneumatic chamber 12b.

In the exemplary embodiment shown, the first pressure generating unit 8 is a compressor which is connected to the pneumatic chamber 12b in a pressure-transmitting manner. In the exemplary embodiment shown, the second pressure generating unit 10 is designed as a hydraulic pump, which is connected to the hydraulic chamber 12a in a pressure-transmitting manner.

The pneumatic chamber 12b of the piston accumulator is preloaded with an adjustable, predetermined gas pressure by the first pressure generating unit 8 or by the compressor. If the hydraulic chamber 11a of the piston accumulator is now subjected to increasing pressure, the piston 13 moves in such a way that the volume of the pneumatic chamber 12b is reduced and the gas is compressed therein. As a result, the same pressure prevails in the pneumatic chamber 12b and the hydraulic chamber 12a, so that gas pressure and liquid pressure are in equilibrium and hydraulic fluid is taken up in the hydraulic chamber 12a. However, if the pressure acting on the hydraulic chamber 12a drops, the compressed gas in the pneumatic chamber 12b and 12b expands reduces the volume of the hydraulic chamber 12a, so that hydraulic fluid is displaced from it.

If, for example, the same pressures are made available by the first pressure generating unit 8 and the second pressure generating unit 10, there is an equal volume between the hydraulic chamber 12a and the pneumatic chamber 12b and the pressure characteristic curve resulting thereby has an angle of 45 °. The angles of the pressure characteristics can be freely selected depending on the pressure and volume ratios selected.

To monitor the pressures that are applied with the first pressure generating unit 8 and the second pressure generating unit 10 in the pneumatic chamber 12b and the hydraulic chamber 12a, two pressure measuring devices 8a and 10a are provided in the pressure lines in the exemplary embodiment shown, which the pressure generating units 8 and 10 connect each with the piston accumulator.

Fig. 6 shows a further embodiment of an inventive

Pressure control system 20. The pressure control system 20 comprises a hydraulic pump 14, which is connected via a pressure line 21 to the pressure cylinder 7 of an active cup 3. In the event that a plurality of knitted cups 3 are present, outlets for each of these knitted cups 3 are present in the pressure line 21.

The pressure control system 20 further comprises three pressure accumulators 15, 15a, 15b, which in the exemplary embodiment shown are air / gas volume accumulators. The pressure accumulators 15, 15a, 15b are each connected to the pressure line 21 via valves 16, 16a, 16b and thus the respective pressure accumulators 15, 15a, 15b can be connected into the pressure line 21 by opening or closing the valves 16, 16a, 16b. In the exemplary embodiment shown, the valves 16, 16a, 16b are simple shut-off valves.

The pressure of the pressure medium acting on the pressure cylinder 7 is set by the pump 14. The same pressure is present in the pressure accumulators 15, 15a, 15b. The pressure accumulators 15, 15a, 15b are designed as bladder accumulators, in which an area filled with gas is separated from an area filled with liquid by a bladder, for example an elastomer bladder. The hydraulic fluid is pressed under pressure into the fluid-filled area of the pressure accumulators 15, 15a, 15b, whereby the gas is compressed in the other area separated by the bladder. If the ratio of the volumes in the pressure accumulators 15, 15a, 15b is changed by opening or closing the valves 16, 16a, 16b, the slope of the pressure characteristic curve of the pressure acting on the pressure cylinder 7 also changes. For example, the gas in the pressure accumulator 15 expands , 15a, 15b when the respective valve 16, 16a, 16b is opened, there is a corresponding increase in the slope of the pressure characteristic curve which acts on the pressure cylinder 7 or the pressure piston 71 of the knitting cup 3, so that the pressure acting on the knitting insert 4 is such is adjustable by opening or closing the valves 16, 16a, 16b.

A flat increase in the pressure characteristic curve can be achieved if, for example, the pump 14 generates a pressure which is applied via the pressure line 21 in the pressure cylinder 7 and, in addition to this pressure, one of the valves 16, 16a, 16b is opened. The slope of this pressure characteristic curve can be increased if an additional or both remaining valves 16, 16a, 16b are opened. The greatest increase in the resulting pressure characteristic curve can be achieved if all three valves 16, 16a, 16b are open.

Depending on the design of the pressure accumulators 15, 15a, 15b and the pressure generated by the pump 14 or the compressor 8, a flatter increase in the resulting pressure characteristic curve can also be achieved by switching on the pressure accumulators 15, 15a, 15b, so that the smallest Slope of the resulting pressure characteristic is achieved when all three valves 16, 16a, 16b are open. Depending on the design of the pressure accumulators 15, 15a, 15b, an increasing or decreasing gradient of the resulting pressure characteristic curve can also be achieved by connecting different pressure accumulators 15, 15a, 15b.

A pressure control unit 20 designed in this way is particularly advantageous in the case of high outputs to be achieved by the active system, since the pressure characteristic curve can be changed quickly due to the rapid response time of the valves 16, 16a, 16b and little or no losses are associated with a change in the pressure characteristic curve , since no re-pumping of the pressure medium is required. This makes it possible to optimally control the properties of the dough pieces 5 in the knitting process even with high system outputs. In the exemplary embodiment shown, the gas-filled side of the pressure accumulators 15, 15a, 15b is prestressed by a compressor 8. The compressor 8 is connected via a pressure line to each of the pressure accumulators 15, 15a, 15b and a pressure measuring device 8a is integrated in the pressure line for checking the pressure applied by the compressor 8. A pressure measuring device 14a is also integrated in the pressure line 21, which connects the pump 14 to the pressure cylinder 7, in order to check the pressure present in the pressure line 21.

Alternatively, a pressure control unit 20 according to the invention can also use other pressure accumulators such as Include membrane or metal bellows accumulator. Any other valves, such as. B. pressure or directional control valves can be provided.

FIG. 8 shows a further example of a pressure control unit 20 according to the invention, in which two buffer stores 22, 22a with variable volume are connected via valves 16, 16a in a pressure-transmitting manner via a pressure line 21 to the pressure cylinder 7 of each active cup 3 of the active system 100. The buffer stores 22, 22a are connected to a pump 14, which can be a hydraulic pump, for example, in a pressure-transmitting manner. The volume or the pressure in the buffer store 22, 22a can be set by means of the pump 14, so that each buffer store 22, 22a has its own pressure characteristic curve. By opening or closing the valves 16, 16a, the buffer stores 22, 22a can be switched into the pressure line 21. By combining the pressure characteristics of the two buffer stores 22, 22a or by changing the pressure or volume in the respective buffer stores 22, 22a, a large number of different resulting pressure characteristics can be achieved and the pressure acting on the pressure piston 71 or on one Dough piece 5 exerted by the active force 4 optimally on z. B. the type of dough to be processed is adjustable.

1 shows a detailed image of two knitted cups 3 of a knitting plant 100 according to the invention. The active cups 3 are arranged opposite the abutment 1 and have an opening 31. In the exemplary embodiment shown, the abutment 1 comprises two knitting nests 2 for fixing the dough pieces 5 on the abutment 1, so that the dough pieces 5 cannot slip during the knitting process, for example, and optimal processing of the dough pieces 5 is thus ensured. In the exemplary embodiment shown, the knitted nests 2 are each formed from three concentrically extending, deepened grooves 23, as can also be seen in FIGS. 2e and 2f.

2a schematically shows a knitting cup 3 which is in the knitting position during the knitting, specifically the round knitting, of a dough piece 5. The dough piece 5 is on the abutment 1 is fixed by the knitting nest 2 and an active gap 6 is formed between the knitting cup 3 and the abutment 1, which serves not to injure the dough piece 5 or its surface during the knitting. The active insert 4 is in contact with the surface of the dough piece 5 since the pressure cylinder 7 and the pressure piston 71 are pressurized.

2b shows a flow diagram 30 of the sequence of an active process. The knitting cup 3 with knitting insert 4 is placed on the dough piece 5, the knitting gap 6 between the abutment 1 and the knitting cup 3 being left free. The width of the active gap 6 is dependent on the strength or the proportion of the liquid substances in the dough piece 5. The deflection 30 of the active cup 3 begins at zero or at a predetermined deflection that is smaller than the maximum set deflection.

The surface of the dough pieces 5 is stretched by the oscillating movement, which the drive unit 18 allows the knitting cup 3 to carry out, and an enlargement of the knitting deflection 30, while the knitted nests 2 fix the dough piece on the abutment 1. This increase in deflection 30a of the effective deflection 30 at the beginning of the knitting process is shown in FIG. 2c. The tension on the surface of the dough pieces 5 increases during the action, so that the dough piece 5 is thereby shaped round and an effective connection is created. In order to keep the effective closure small, a deflection reduction 30b of the effective deflection 30, which is shown in FIG. 2d, is carried out after the round shape of the dough piece 5 has been formed.

A knitting plant 100 according to the invention can advantageously be integrated in dough processing plants for example dough strips. In this context, dough processing systems are understood to mean systems in which dough strips are portioned into dough pieces 5 and these dough pieces 5 are each further processed.

For integration into such a dough processing system, the abutment 1 can have a take-over side for taking portioned, unprocessed dough pieces 5 from a first section of the dough processing system and a transfer side for transferring knitted dough pieces 5 to a further section of the dough processing system. For this purpose, the abutment 1, for example, as Endless conveyor belt rotating about deflection rollers, which is arranged on the knitting system 100.

On one side of the abutment 1 or conveyor belt, the portioned, unprocessed dough pieces 5 are transferred to the knitting machine 100 for knitting, while on the other side of the conveyor belt or the abutment 1 knitted by the knitting machine 100, they are fully knitted to a further area of the dough processing plant for further processing Processing steps are passed.

Claims

1. Knitting plant (100) for knitting dough pieces (5), comprising

- At least one knitted cup (3), each with an opening (31), a receiving space

5 (32) for receiving dough pieces (5) and an active insert (4),

the active insert (4) delimiting the receiving space (32) on its side facing away from the opening (31),

- an abutment (1) which is arranged opposite the opening (31) of the active cup (3),

0 - a height adjustment device (17), which is designed to at least one

Knitting cup (3) reversible, in particular mechanically, from an initial position remote from the abutment (1) into an active position close to the abutment (1); electromechanical, pneumatic or hydraulic, to adjust, and

a drive unit (18) which is designed to set the at least one knitting cup (3) 5 into an oscillating movement,

characterized,

- That the at least one knitted cup (3) each has a pressure cylinder (7) with a pressure piston (71) movable therein and

- That a pressure control unit (20) is provided,

: Q where the pressure control unit (20) transmits pressure with the

Pressure cylinder (7) is connected,

wherein the pressure control unit (20) is designed to apply a variable pressure and / or volume to the pressure cylinder (7) and the pressure piston (71) is connected to the active insert (4): 5 in a pressure-transmitting manner in such a way that in the event of a change of the pressure in the pressure cylinder (7) and / or the pressure characteristic curve of the pressure control unit (20) the force on the active insert (4) can be changed.

2. knitting system (100) according to claim 1, characterized in that the 0 pressure control unit (20) is designed to the pressure cylinder (7) each with a predetermined, constant pressure or at least one predetermined, in particular variable, pressure characteristic corresponding pressure to be acted upon so that the force acting on the active insert (4) can be adjusted in each case.

5 3. knitting system (100) according to claim 1 or 2, characterized in that the

Pressure control unit (20) comprises a first pressure generating unit (8) and a second pressure generating unit (10), wherein the first pressure generating unit (8) and the second pressure generating unit (10) are each pressure-transmitting connected to a pressure transmission unit (1 1) and are designed such that in the pressure transmission unit (1 1) a pressure corresponding to at least one predetermined, in particular variable, pressure characteristic is adjustable, and

wherein the pressure transmission unit (1 1) is connected to the pressure cylinder (7) in a pressure-transmitting manner.

4. knitting system (100) according to claim 3, characterized in that the pressure transmission unit (1 1) is designed as a piston accumulator,

the piston accumulator has a hydraulic chamber (12a), in particular filled with liquid, a pneumatic chamber (12b), in particular filled with gas, and a piston (13) arranged between the hydraulic chamber (12a) and the pneumatic chamber (12b),

the first pressure generating unit (8), in particular a compressor, is connected to the pneumatic chamber (12b) in a pressure-transmitting manner,

the second pressure generating unit (10), in particular a hydraulic pump, is connected to the hydraulic chamber (12a) in a pressure-transmitting manner,

- A pressure in the piston accumulator being pressurized in the hydraulic chamber (12a) corresponding to at least one predetermined, in particular variable, pressure

Characteristic curve is adjustable, and

- The piston accumulator is designed to change the pressure and / or the volume in the pressure cylinder (7).

5. knitting system (100) according to claim 1 or 2, characterized in that the

Pressure control unit (20) comprises at least one pump (14) and a number of pressure accumulators (15, 15a, 15b),

- The at least one pump (14) being connected to the pressure cylinder (7) via a pressure line (21),

- The pressure accumulator (15, 15a, 15b) each via valves (16, 16a, 16b) in the

Pressure line (21) can be switched on and each have a predetermined, in particular variable, pressure characteristic, and

- The pressure control unit (20) is designed, in particular by opening and / or closing the valves (16, 16a, 16b), the pressure cylinder (7) of the at least one kneading cup (3) each with a pressure corresponding to one of the pressure Characteristics of the pressure accumulator (15, 15a, 15b) resulting, in particular variable, pressure characteristic.

6. knitting system (100) according to one of the preceding claims, characterized in that the knitting insert (4) is designed to transmit the pressure transmitted from the pressure piston (71) to the knitting insert (4) as a force acting orthogonally to the abutment (1) .

7. knitting system (100) according to any one of the preceding claims, characterized in that the abutment (1) has at least one, in particular in the form of one or more recesses, knitting nest (2) for fixing the dough pieces on the abutment (1), wherein In particular, it is provided that the knitted nest (2) consists of one

Number of concentric recessed grooves (21) is formed.

8. knitting system (100) according to one of the preceding claims, characterized in that in the knitting position (WP) in each case a knitting gap (6) is formed between the knitting cup (3) and the abutment (1).

9. knitting system (100) according to one of the preceding claims, characterized in that - the knitting insert (4) each has a smooth or structured surface and / or

- That the receiving space (32) has a curved or semicircular cross section and / or a round or oval projection surface.

10. knitting system (100) according to any one of the preceding claims, characterized in that the pressure characteristic of the pressure control unit (20) according to the dough rheology and / or the initial shape of the dough pieces (5) is adjustable.

1 1. dough processing plant for processing dough strips comprising a knitting plant (100), characterized in that the knitting plant (100) is designed according to one of claims 1 to 10,

wherein the abutment (1) has a transfer side for the transfer of, in particular pre-portioned, unprocessed dough pieces (5) and a transfer side for the transfer of knitted dough pieces (5) and

the dough processing system comprising at least one transport device which is designed to transfer in particular pre-portioned, unprocessed dough pieces (5) to the transfer side of the abutment (1) to the abutment (1) and / or knitted dough pieces (5) on the transfer side of the abutment (1) to take over from the abutment (1).