Baking appliance with a segmented pair of busbars

Description

[0001] The invention relates to a baking device according to the preamble of the independent patent claim.

[0002] The invention relates in particular to a baking apparatus, especially an oven, for the industrial production of baked, preferably edible, products, in which a plurality of baking plate devices are continuously conveyed through different areas along a continuous conveyor. A continuous conveyor is an endless conveying element such as a continuously driven conveyor chain.

[0003] The baking plate devices of this type of baking appliance are usually designed as baking tongs and comprise two baking plates. In an open position, dough or a baking mixture is applied to the lower baking plate. Subsequently, the respective baking tong is advanced, closed, and moved through a baking chamber. According to the prior art, the baking chamber is usually heated by a gas heater, whereby the dough placed between the two baking plates is baked by heat conduction in the baking plates.

[0004] There are two different types of ovens. Ovens in which the dough is baked essentially without pressure, and ovens in which pressure baking molds are created by the baking plate devices.

[0005] After the baking chamber, the baking plate units are opened, and the baked wafer sheets can be removed one by one. Then, batter is applied to the open baking plate unit, and the process begins again. The baking plate units are typically attached one after the other to the continuous conveyor.

[0006] Devices are known in the prior art in which the baking plates each have a moving electric heating element. These moving heating elements are powered via sliding contacts and stationary busbars.

[0007] In a known design, resistance heaters on the baking plates are powered by DC voltage. However, in this design, the power electronics must be protected by ultra-fast NH fuses in case of a short circuit, which increases costs. Short circuits can be caused by the resistance heaters of the baking plates themselves or by pouring batter over the baking plates. Pouring batter over the baking plates results in increased baking waste, which, due to the lack of heat compared to gas-heated ovens, is not baked off and can then lead to a short circuit on a busbar.

[0008] According to another well-known electrical heating system, the resistance heaters are powered by single-phase AC voltage from an inverter. This has the advantage over DC power supply that short circuits are detected by the power electronics, eliminating the need for additional, expensive protection circuits. While the single-phase design is technically simple to implement, it has the disadvantage that only about 70% of the available inverter power can be utilized.

[0009] There is now a demand for ovens of this type with improved efficiency. Efficiency can be improved by making the oven more energy-efficient, resulting in lower energy costs for the same baking performance. Efficiency can also be improved by making production more efficient, particularly by reducing waste, but also by improving service life and / or reducing maintenance time.

[0010] The object of the invention is now to create a baking device with improved efficiency.

[0011] The problem is solved in particular by the combination of features of the independent patent claim.

[0012] The invention relates in particular to a baking device for producing baked, preferably edible, products. Preferably, several openable and closable baking plate devices are provided.

[0013] In particular, it is provided that the baking plate devices each have two baking plates and a baking mold formed between the closed baking plates for a baking mixture or dough.

[0014] Preferably, an endless conveyor is provided which continuously feeds the baking plate devices into a series: conveyed through a baking mass application area for introducing a baking mass into the opened baking plate devices, through a closing area for closing and, if necessary, locking the baking plate devices, through a baking area for baking the baking mass arranged in the baking plate devices, through an opening area for opening the baking plate devices, and through a removal area for removing the molded bodies baked from the baking mass.

[0015] Preferably, at least one stationary pair of conductor rails is provided following the endless conveyor, comprising two conductor rails.

[0016] Preferably, each baking plate is equipped with a moving electric heater, in particular an electric resistance heater.

[0017] Preferably, each backplate has two sliding contacts for electrically connecting the moving backplate device to the stationary pair of busbars.

[0018] In all embodiments, one sliding contact of a baking plate is electrically connected to one busbar, and the other sliding contact of the same baking plate is electrically connected to the other busbar of the busbar pair. This means that the heating element, in particular the heating resistor, of this baking plate is electrically connected between these two busbars.

[0019] Preferably, a 3-phase alternating current source with a first phase conductor U, a second phase conductor V and a third phase conductor W is provided for the power supply of the electric heaters.

[0020] Preferably, the busbar pair has at least three sections in which different phase conductor pairs of the 3-phase AC power source are connected to the two busbars.

[0021] The following is preferred: that the phase pairing of first phase conductor U and second phase conductor V is connected to the busbars of the first section, that the phase pairing of second phase conductor V and third phase conductor W is connected to the busbars of the second section, and that the phase pairing of third phase conductor W and first phase conductor U is connected to the busbars of the third section.

[0022] Preferably, insulators are provided which electrically isolate the busbars of one section of the busbar pair from the busbars of the adjacent section along the course of the busbar pair.

[0023] In particular, it is intended that the insulators are adapted to the shape of the busbars and / or connect two adjacent busbars in alignment.

[0024] Preferably, at least two 3-phase AC power sources are provided, wherein the 3-phase AC power sources are in particular the outputs of two different 3-phase inverters.

[0025] Preferably, two pairs of busbars running parallel to each other are provided.

[0026] Preferably, the first pair of power rails supplies power to all lower baking plates. Preferably, the second pair of power rails supplies power to all upper baking plates.

[0027] If necessary, it is provided that both busbar pairs are supplied by the same 3-phase AC power source (14).

[0028] Alternatively, it is planned that each pair of busbars will be supplied by its own 3-phase AC power source.

[0029] If necessary, the conductor rail pair or pairs are provided for to each have at least six sections.

[0030] If necessary, it is provided that the different phase conductor pairs of a first 3-phase AC power source are connected to the busbars of three sections.

[0031] If necessary, the different phase conductor pairs of a second 3-phase AC power source are connected to the busbars of the other three sections.

[0032] If necessary, it is provided that, in case further sections, in particular three further sections, are provided, the different phase conductor pairs are connected to at least one further 3-phase AC power source.

[0033] Six sections may be provided. It may be provided that... that the phase pairing of the first phase conductor U' and second phase conductor V' of the first 3-phase AC power source is connected to the busbars of the first section, that the phase pairing of the second phase conductor V' and third phase conductor W' of the first 3-phase AC power source 14' is connected to the busbars of the second section 13", that the phase pairing of the third phase conductor W' and first phase conductor U' of the first 3-phase AC power source is connected to the busbars of the third section, that the phase pairing of the first phase conductor U" and second phase conductor V" of the second 3-phase AC power source is connected to the busbars of the fourth section, that the phase pairing of the second phase conductor V" and third phase conductor W" of the second 3-phase AC power source is connected to the busbars of the fifth section,and that the phase pairing of the third phase conductor W" and the first phase conductor U" of the second 3-phase AC power source is connected to the busbars of the sixth section.

[0034] If necessary, the two 3-phase AC power sources are intended to supply the busbars with different, in particular selectable, electrical powers.

[0035] If necessary, it is provided that the baking plate devices in the area of ​​the sections of the first 3-phase AC power source are heated with a different heating power than in the area of ​​the sections of the second 3-phase AC power source.

[0036] If necessary, the first 3-phase AC power source is connected to three adjacent sections along the route of the busbar pair.

[0037] If necessary, the second 3-phase AC power source is provided for to be connected to three adjacent sections along the course of the busbar pair.

[0038] If necessary, it is provided that two different heating zones are formed, arranged one after the other along the course of the busbar pair.

[0039] If necessary, it is provided that each baking plate is only ever powered by a single section.

[0040] If necessary, the insulators along the course of the busbar pair are dimensioned at least so that a short circuit and / or an arc between two adjacent sections of the respective busbar is prevented when the sliding contacts pass over them.

[0041] If necessary, it is provided that all sections in which different phase conductor pairs of one, i.e., one and the same, 3-phase AC power source are connected to the two busbars have the same length. If necessary, it is provided that all sections in which different phase conductor pairs of one, i.e., one and the same, 3-phase AC power source are connected to the two busbars supply the same number of baking plates with electrical power.

[0042] If necessary, the busbar pair may include a measuring section.

[0043] If necessary, a measuring device is provided in the measuring section to measure electrical parameters of the baking plates, such as in particular the electrical resistance of the heating of the baking plates and / or the electrical resistance or insulation to earth.

[0044] If necessary, the measuring device continuously records parameters of the baking plates conveyed through the measuring section, preferably during each pass.

[0045] If necessary, a database is provided in which the recorded parameters of the measuring device are stored and, if applicable, assigned to a value identifying the backplate.

[0046] If necessary, the measuring section is provided in addition to the current-carrying sections of the busbar pair or pairs.

[0047] The special wiring of the phase conductors allows the power provided by the 3-phase AC power source to be optimally utilized, in particular up to 100%.

[0048] The sections are formed in particular by segmenting the busbar pair or pairs. Insulators are preferably arranged between the sections so that their busbars are electrically separated from each other, allowing different phase pairings to be connected to the different sections.

[0049] In all embodiments, in addition to the pair or pairs of busbars, a grounded ground busbar can be provided, which serves as grounding for the baking plate assemblies. In particular, all baking plate assemblies can be provided with an additional sliding contact that is in electrical contact with the ground busbar. This ground busbar can be configured without insulators or sections. In particular, a single continuous ground busbar can be provided for all sections.

[0050] By selecting the number and / or power of the 3-phase alternating current sources, the heating power and therefore the number of baking plate devices of the baking appliance can be freely chosen during the design of the baking appliance.

[0051] In particular, the number of baking trays and thus the throughput of the baking system can be flexibly scaled. For example, two 3-phase AC power supplies can provide electrical power to six sections of the busbar pair. For example, three 3-phase AC power supplies can provide electrical power to nine sections of the busbar pair. For example, four 3-phase AC power supplies can provide electrical power to twelve sections of the busbar pair. For example, two 3-phase AC power supplies can provide electrical power to six sections of the busbar pair for the lower baking trays, and two 3-phase AC power supplies can provide electrical power to six sections of the busbar pair for the lower baking trays. Similarly, this can also be extended to three or more 3-phase AC power supplies per busbar pair.If the different 3-phase alternating current sources deliver different electrical power outputs, different heating zones can be formed in the baking appliance.

[0052] The baking device includes in particular a baking plate device, for example a baking tong, for producing crispy brittle waffles baked under overpressure from a baking mixture containing 50-70% water in the unbaked state, comprising: two support frames, each having at least one support, two baking plates, each attached to one of the support frames, and two connecting devices arranged on both sides of the baking plates and connected to each other via the supports.

[0053] In particular, the baking device is designed as a waffle oven for the industrial production of waffles.

[0054] Preferably, the baking plate device includes rollers, so that the baking plate device is designed, for example, as a baking tong carriage. Optionally, the baking plate device includes guide rollers for lateral guidance of the baking plate device along its path of movement in the baking appliance.

[0055] The baking plate device may include control elements which are in operative contact with control elements of the baking device, such as a cam of the baking device, to control a movement, for example to open and close the baking plate device.

[0056] The design allows the materials for the support frames and baking plates to be selected independently. This makes it possible to choose a baking plate material with high heat capacity that ensures uniform heat conduction and distribution across the entire baking pan.

[0057] Baking trays and support frames can be made of the same materials to avoid differences in thermal expansion. However, it is also conceivable that the support frames are made of a different material than the baking trays.

[0058] In particular, the support frame can be made of cast iron, for example, ductile iron. The support frames may be assembled from profiles or cast in one piece. The baking plates are preferably made of cast iron, especially ductile iron.

[0059] Preferably, an adjustment arrangement is provided that allows the position and / or alignment of a baking plate relative to the support frame to which the baking plate is attached. The adjustment arrangement preferably includes several adjusting means, such as adjusting screws.

[0060] If necessary, the backing plates are connected to the support frame by means of the adjustment devices.

[0061] If necessary, the baking plates are attached to the support frame exclusively by means of the adjustment devices.

[0062] If necessary, it is provided that one, in particular the first, connecting device is designed as a hinge and the other, in particular the second, connecting device is designed as a locking device, so that the baking plate device is designed as a baking tong.

[0063] If necessary, it is provided that sealing strips and / or steam strips are provided to form the overpressure baking mold.

[0064] Preferably, the power outputs or power inputs of all heating elements in all three sections of a 3-phase alternating current source are equal.

[0065] Preferably, an equal number of backplate devices are connected to all sections of an AC power source, thus optimally utilizing the three different phases of the AC power source. Preferably, the individual sections connected to an AC power source or to its different phase pairs are of the same length. However, the length of the sections of the first AC power source can differ from the length of the sections of the second AC power source.

[0066] Preferably, all sliding contacts of a baking plate device, i.e., the sliding contacts of the upper baking plate and the sliding contacts of the lower baking plate, are arranged on one side of the baking plate device and in particular on the lower baking plate of the baking plate device.

[0067] Preferably, the supply of electrical power from the sliding contacts to the other side, in particular to the upper baking plate, is provided via two conductors guided over the hinge of the baking plate device.

[0068] The invention will subsequently be described in more detail with reference to exemplary embodiments, in particular with reference to the figures. Fig. 1 shows a schematic diagram of components of a baking device, with only some of the lower baking plates shown for clarity. Fig. 2 shows a schematic diagram of components of a baking device, with some baking tongs with upper and lower baking plates shown. Fig. 3 shows a schematic diagram of another possible embodiment of a busbar pair. Fig. 4 shows a schematic sectional view of a possible embodiment of a baking plate device.

[0069] Unless otherwise specified, the reference numerals correspond to the following components: first phase conductor U, second phase conductor V, third phase conductor W, baking plate device 1, lower baking plate 2, upper baking plate 3, continuous conveyor 4, baking mass application area 5, closing area 6, baking area 7, opening area 8, dispensing area 9, busbar pair 10, busbar 11, busbar 12, section (of a busbar pair) 13, AC power source 14, inverter 15, measuring section 16, measuring device 17, database 18, resistance heater / heater 19, sliding contact 20, insulator 21, heating resistor 22, cover plate 23, support frame 24, hinge 25, locking device 26, electrical conductor 27.

[0070] Fig. 1 shows a schematic view, in particular a schematic diagram, of components of a baking appliance.

[0071] The baking device comprises a continuous conveyor 4, which is shown as a dashed line and can be designed according to the prior art. For example, the continuous conveyor 4 is a chain circulating along a closed contour, to which baking plate assemblies 1 are attached for conveying them through the baking device. In the present illustration, only some baking plate assemblies 1 are shown, and of these, only the lower baking plates 2, in order to better describe the function of the components. In all embodiments, it is preferably provided that the baking plate assemblies 1 are arranged essentially in series along the entire continuous conveyor 4.

[0072] The term "lower baking plate 2" preferably refers to the baking plate that is arranged along the bottom of the upper conveying surface of the continuous conveyor 4 or onto which the dough is applied. The dough or baking mixture that is baked into a finished product or molded part in the baking device is also typically applied to the lower baking plate 2.

[0073] The baking plates 2 are equipped with a heating element 19. Specifically, the heating elements 19 are attached to the baking plates 2 and thus form part of the baking plate assemblies 1. The heating elements 19 are electric heating elements, specifically resistance heating elements. The electrical energy for operating the heating elements 19 is supplied via a busbar pair 10. In the present embodiment, the busbar pair 10 comprises two busbars 11 and 12, in particular a first busbar 11 and a second busbar 12. The busbar pair 10 is preferably configured to follow the continuous conveyor 4 or the path of the continuous conveyor 4. The baking plate assemblies 1 thus move along the busbar pair 10 as they move through the baking appliance. To transfer the electrical power from the busbar pair 10 to the baking plate assemblies 1 and their heating elements 19, the baking plate assemblies 1 include sliding contacts 20.These sliding contacts 20 contact the busbar pair 10 during relative movement of the baking plate devices 1 with respect to the busbar pair 10. In all embodiments, each heater 19 preferably comprises at least one heating element 22, e.g., a heating coil. Each heating element 22 is connected on both sides to a sliding contact 20. The heating element 22 is preferably arranged internally and covered by the baking plate 2, 3. The illustration of the heating element 22 is only symbolic, for a better understanding of the construction of the baking plate device 1.

[0074] In the present embodiment, the busbar pair 10 is divided into three sections 13', 13", 13‴ or the busbar pair 10 comprises three sections 13', 13", 13‴. Sections 13', 13", 13‴ and their busbars 11, 12 are each separated from one another by insulators 21. In all embodiments, the insulators 21 are preferably adapted to the shape of the busbars 11, 12. When a baking plate device 1 with its sliding contacts 20 moves along the busbars 11, 12, power is transferred from the busbars 11, 12 to the heating element 19. However, no power is transferred in the area of ​​the insulators 21. Rather, the insulator 21 is designed along the length of the busbars 11, 12 such that it is long enough to prevent a short circuit between the busbars 11, 12 and sections 13', 13", 13‴.In this embodiment, no electrical power is transferred to the heater 19 in a short area.

[0075] Generally, an alternating current source 14 is provided to supply the electrical power. In the present embodiment, this alternating current source 14 is preferably an inverter 15, which is supplied by a suitable power source.

[0076] The AC power source 14 is preferably a 3-phase AC power source 14 with a first phase conductor U, a second phase conductor V, and a third phase conductor W. In the present embodiment, and preferably in all embodiments, the phase conductors U, V, W of the AC power source 14 are specifically connected to the individual busbars 11, 12 of the busbar pairs 10 or their sections 13. Thus, different phase conductor pairs of the 3-phase AC power source 14 are connected to all three sections 13', 13", 13‴.

[0077] The 3-phase AC power source 14 basically has three possible different phase conductor pairings, namely UV, VW and WU.

[0078] In the present embodiment, for example, the phase pair of first phase conductor U and second phase conductor V can be connected to the busbars 11, 12 of the first section 13'. For example, the phase pair of second phase conductor V and third phase conductor W can be connected to the busbars 11, 12 of the second section 13". For example, the phase pair of third phase conductor W and first phase conductor U can be connected to the busbars 11, 12 of the third section 13‴.

[0079] This wiring configuration allows the available power of the 3-phase AC power source 14 to be optimally utilized.

[0080] In particular, it is provided that the individual sections 13 are essentially the same length and / or supply at least the same number of baking plate devices 1 with power. This ensures that the same power is drawn by the baking plate devices 1 in each section 13', 13", 13‴.

[0081] Fig. 2 Figure 1 shows a schematic diagram of an embodiment of a baking device, in which several baking plate assemblies 1, each with a lower baking plate 2 and an upper baking plate 3, are shown. Again, for clarity, not all baking plate assemblies 1 are shown.

[0082] In the baking device, dough or a baking mixture is applied to the open baking plate device 1 in a baking mixture application area 5. In a subsequent closing area 6, the baking plate devices 1 are closed. In the subsequent baking area 7, the baking mixture is baked in the baking plate device 1. Since, in the present embodiment, electrical energy is preferably transferred to the heating elements 19 of the baking plate devices 1 along their entire circumference, the baking area 7 essentially extends over the entire circumference of the baking plate devices 1. An exception to this is the area in which no baking mixture is provided in the baking plate devices 1. In this case, the baking plate devices 1 are opened in an opening area 8, and the baked molded parts or products are removed from the baking plate devices 1 in a removal area 9.Consequently, there is no baking mass on the baking plate device 1 after this area and before the baking mass application area 5. The basic operating principle of the baking process in baking tongs is well known.

[0083] The construction of Fig. 2 essentially corresponds to the construction from Fig. 1 In addition to the lower baking plates 2, upper baking plates 3 are also shown, which are also connected to a pair of busbars 10 via sliding contacts 20.

[0084] In principle, the heating elements 19 of the upper baking plates 3 and the lower baking plates 2 could be supplied with electrical power from the same pair of busbars 10. However, in the present embodiment, two pairs of busbars 10', 10" are provided, with one pair of busbars 10' supplying the heating elements 19 of the lower baking plates 2 and the second pair of busbars 10" supplying the heating elements 19 of the upper baking plates 3 with electrical power.

[0085] Preferably, in this embodiment, two AC power sources 14', 14" or two inverters 15', 15" are provided, each connected to one of the busbar pairs 10', 10". As noted, however, only one 3-phase AC power source 14 or one inverter 15 could also be provided, to which the two busbar pairs 10', 10" are connected in parallel. Analogous to the embodiment of the Fig. 1 The conductor rail pairs 10, or their conductor rails 11, 12, have several sections 13', 13", 13‴. Similarly to Fig. 1 The different phase conductor pairs are connected to these sections 13', 13", 13‴.

[0086] The busbar pairs 10 can be designed identically for the upper baking plates 3 and the lower baking plates 2 and, in particular, can run side by side.

[0087] Preferably, the sliding contacts 20 of the lower baking plates 2 and the upper baking plates 3 project from one side of the baking plate assemblies 1. In the present embodiment, these project from the area of ​​the lower baking plate 2 into the interior of the orbit of the baking plate assemblies 1, where the busbar pairs 10', 10" also run. In order to conduct the electrical power from this area to the upper baking plate 3, conductors 27 can run from the sliding contacts 20 of the upper baking plates 3 along the lower baking plates 2, and then, in the area of ​​the connection between the upper baking plate 3 and the lower baking plate 2, to the upper baking plate 3 in order to supply the heating elements 19 of the upper baking plates 3 with electrical power.

[0088] In particular, the lower baking plates 2 are connected to the upper baking plates 3 via hinges 25. A flexible conductor 27 in the area of ​​these hinges 25 allows power to be easily transferred to the upper baking plate 3.

[0089] In the schematic representations of the Figuren 1 and 2 The busbars 11, 12 are formed by the three sections 13', 13", 13‴ and by the sections 13', 13", 13‴ and the insulators 21, respectively. The heaters 19 of the baking plate devices 1 are thus continuously supplied with electrical power, with the exception of the areas of the insulators 21.

[0090] According to a possible alternative embodiment, however, further areas may be provided in which a different electrical power or no electrical power is transferred to the heaters 19 of the baking plate devices 1. For example, an area may be provided in the baking mass application area 5 in which no electrical energy is transferred to the heaters 19.

[0091] Fig. 3 shows a schematic diagram of another possible configuration of the wiring of the busbar pairs 10 or their sections 13. In Fig. 3 A schematic representation of a busbar pair 10, comprising several sections 13, is shown. For clarity, only one busbar pair 10 is depicted. As in Fig. 2 As shown, two pairs of power rails 10', 10" can be provided for the upper and lower baking plates 2, 3.

[0092] In the present embodiment, two AC power sources 14' and 14" are provided for the busbar pair 10. These each have 3-phase conductors U', V' and W' or U", V" and W" respectively. For two busbar pairs 10, analogous to Fig. 2 , four AC power sources 14' can be provided.

[0093] The busbar pair 10 now has six sections 13' to 13‴‴, each of which is connected to different phase pairings of the two 3-phase AC sources 14', 14".

[0094] In particular, the wiring is designed in such a way that that six sections 13', 13", 13‴, 13"", 13ʺ‴, 13‴‴ are provided, that the phase pairing of the first phase conductor U' and second phase conductor V' of the first 3-phase AC source 14' is connected to the busbars 11, 12 of the first section 13', that the phase pairing of the second phase conductor V' and third phase conductor W' of the first 3-phase AC source 14' is connected to the busbars 11, 12 of the second section 13", that the phase pairing of the third phase conductor W' and first phase conductor U' of the first 3-phase AC source 14' is connected to the busbars 11, 12 of the third section 13‴, that the phase pairing of the first phase conductor U" and second phase conductor V" of the second A 3-phase AC power source 14" is connected, so that the busbars 11,12 of the fifth section 13‴ʺ, the phase pairing of the second phase conductor V" and the third phase conductor W" of the second 3-phase AC source 14" is connected, and that the phase pairing of the third phase conductor W" and the first phase conductor U" of the second 3-phase AC source 14" is connected to the busbars 11, 12 of the sixth section 13‴‴.

[0095] The same circuitry can also be used for the upper baking plates 3.

[0096] This interconnection allows different sections 13 to be supplied with different electrical power, thus creating different heating zones.

[0097] For example, the first 3-phase AC power source 14' can provide a different electrical power than the second 3-phase AC power source 14", which means that the heaters 19 connected to the different AC power sources 14', 14" receive / deliver different heating power. This allows the baking plate devices 1 to be heated differently in different areas along the circulation.

[0098] Preferably, the electrical power of the different 3-phase AC power sources 14', 14", can be adjusted or selected, in particular by means of different 3-phase inverters 15. This allows different baking zones to be formed in the baking device 1, whose heating power or baking temperatures can be selected individually.

[0099] The busbar pair 10 of the version of the Fig. 3 The system also includes a further area, namely a measuring section 16. Such an area can be provided in all embodiments. A measuring device 17 is provided in this measuring section 16. As the system passes through the measuring section 16, the measuring device 17 can record parameters of the baking plate devices 1. For example, a resistance measurement can be taken at the heating elements 19 of the baking plate devices 1. The parameters or the parameter data can be stored in a database 18 and, if necessary, further processed. The measuring device 17 can perform continuous monitoring of the baking plate devices 1, thereby enabling early detection of any defects in the heating elements 19 or the baking plate devices 1. This allows the efficiency of the baking system to be improved through early detection of damage.

[0100] In the embodiment of the Fig. 3 Each of the same number of baking plate devices 1 is connected to all sections 13 of an AC power source 14, thus optimally utilizing the three different phases of the AC power source 14. Preferably, the individual sections 13 connected to an AC power source 14 or to its different phase pairs are of the same length. However, the length of the sections 13 of the first AC power sources 14' can differ from the length of the sections 13 of the second AC power sources 14".

[0101] Fig. 4 shows a schematic sectional view of a possible embodiment of a baking plate device 1 for use in the baking device, as for example in a baking device according to Fig.1 , Fig. 2 or Fig. 3 can be used. The baking plate device 1 comprises a lower baking plate 2 and an upper baking plate 3. A plurality of such baking plate devices 1 can be used in the embodiments of the Figuren 1 , 2 and 3 be attached along an endless conveyor 4 in order to be conveyed through the baking device.

[0102] Both the lower baking plate 2 and the upper baking plate 3 are each equipped with a heater 19. The heater 19 is preferably an electric heater, and in particular a resistance heater. For this purpose, a heat-conducting plate, for example an aluminum plate, can be attached to the back of the baking plates 2, 3. Preferably, this heat-conducting plate is thermally conductive and preferably has a flat surface connection to the back of the respective baking plate 2, 3. A heating element 22, such as a heating coil, can be embedded in this heat-conducting plate. Preferably, this heating element 22 is arranged in a meandering, loop-like, or flat pattern along the baking plates 2, 3 in order to heat them substantially uniformly. An outer cover plate 23 can be provided on the outside of these plates or the heating elements 22.

[0103] Alternatively, in all embodiments, the heating element 22 can be arranged in a groove provided in the back of the baking plate 2, 3, thus eliminating the need for the heat-conducting plate. Here too, the heating elements 22 can be arranged in a meandering or planar configuration.

[0104] The heating resistors 22 are preferably arranged internally in all embodiments and are therefore not visible. The schematic representations of the Fig. 1 and Fig. 2 The heating resistors 22 are shown only symbolically for a better understanding of the construction of the heating elements 19.

[0105] In principle, the baking plate assembly 1 can be self-supporting, with the lower baking plate 2 directly connected to the upper baking plate 3 by a hinge. However, in the present embodiment, a support frame 24 is provided, comprising two frame parts connected by a hinge 25. Each frame part supports one of the baking plates 2, 3. Specifically, the frame parts are connected to the baking plates 2, 3 via adjusting screws, allowing the shape and position of the baking plates 2, 3 relative to the support frame 24 to be adjusted. Furthermore, a locking device 26 can be provided to form a pressure-molded baking mold.

[0106] Sliding contacts 20' and 20" are provided for transmitting electrical power to the heating elements 19. The sliding contacts 20' supply electrical power to the heating element 19 of the lower baking plate 2. The sliding contacts 20" supply electrical power to the heating element 19 of the upper baking plate 3.

[0107] In this embodiment, and preferably in all embodiments, the sliding contacts 20 protrude in one direction from the backplate device 1. This allows the busbar pairs 10 to be arranged parallel to each other.

[0108] To transmit the power supply from one side of the baking plate assembly 1 to the other, conductors 27 are provided, extending from the sliding contacts 20" across the area of ​​the hinge 25 to the heating element 19 of the upper baking plate 3. The conductors 27 are designed to be flexible or movable, at least in the area of ​​the hinge 25, to allow the baking plate assembly 1 to be opened and closed.

[0109] Preferably, in measuring section 16, the power supplies to the heaters 19 of the baking plates 2, 3 are disconnected. In this section, instead of measuring the power supply to the heater 19, a measurement of the ohmic resistance of the heating resistors 22, in particular the heating windings, is preferably performed. Alternatively or additionally, a resistance measurement or an insulation measurement with respect to ground can be carried out. The ohmic measurement preferably provides a diagnosis of the condition of the heating resistor 22 for each baking plate 2, 3 and, if necessary, a trend analysis to predictively detect defects. This is achieved, in particular, by data processing that, for example, detects a change in resistance over time. Possible detectable defects include: a blown fuse in the terminal box of the baking plate device 1, wear of the current collectors or the sliding contacts 20, general contact problems, an impending short circuit of the heating resistor 22 or the heating winding, a defect of the heating resistor 22, for example a blown heating winding.

[0110] In the event of a gradual or impending defect, a warning signal can be issued. For example, an error message is generated with the specific identification of a baking plate 2, 3 or a baking plate number. Upon detection of an approaching defect, the affected baking plate 2, 3 can be disconnected from the power supply, for example, by an electromagnetic actuator. This allows, for instance, the sliding contacts 20 of this baking plate assembly 1 to be folded in and thus disconnected from the busbar pair 10. In this case, the control unit of the baking assembly can adjust the batter infusion for this baking plate 2, 3.

[0111] The measurement of the individual resistances of the baking plates 2, 3 can be carried out, for example, when the oven is cold before baking, while in operation (online) or during service operation for individual baking plates 2, 3.

[0112] Preferably, the measuring section 16 is only long enough that only the current collectors of a baking plate 2, 3 are in electrical contact with it at any given time. This allows the measurement of a single baking plate 2, 3. Alternatively, the measuring section 16 is only long enough that only the current collectors of a baking plate assembly 1 are in electrical contact with it at any given time. This also allows the measurement of a single baking plate assembly 1.

[0113] In principle, the measuring section 16 can be located anywhere along the busbar pair 10. Placement in the area of ​​the oven's rear deflection point appears advantageous, as baking plates 2 and 3 can be precisely positioned there during servicing. Furthermore, accessibility is better in the area of ​​the rear deflection point compared to other areas.

Claims

1. A baking device for producing baked, preferably edible, products, - wherein a plurality of openable and closable baking plate devices (1) are provided, - wherein each baking plate device (1) has two baking plates (2,3) and a baking mould for a baking mass formed between the closed baking plates (2,3), - wherein an endless conveyor (4) is provided, which continuously conveys the baking plate devices (1) one after the other through: - a baking mass application region (5) for introducing a baking mass into the opened baking plate devices (1), - a closing region (6) for closing and optionally locking the baking plate devices (1), - a baking region (7) for baking the baking mass arranged in the baking plate devices (1), - an opening region (8) for opening the baking plate devices (1), - and through a removal region (9) for removing the moulded bodies baked from the baking mass, - wherein at least one stationary busbar pair (10) following the endless conveyor (4) is provided, which comprises two busbars (11,12), - wherein each baking plate (2,3) is equipped with a travelling electrical heater (19), in particular an electrical resistance heater, - wherein each baking plate (2,3) has two sliding contacts (20) to electrically connect the moving baking plate device (1) to the stationary busbar pair (10), - and wherein, for supplying power to the electrical heaters (19), a 3-phase AC power source (14) having a first phase conductor (U), a second phase conductor (V), and a third phase conductor (W) is provided, characterised - in that the busbar pair (10) has at least three sections (13), where different phase-conductor pairings of the 3-phase AC power source (14) are connected to the two busbars (11, 12).

2. The baking device according to claim 1, characterised - in that three sections (13', 13", 13‴) are provided, - in that the phase pairing of first phase conductor (U) and second phase conductor (V) is connected to the busbars (11,12) of the first section (13'), - in that the phase pairing of second phase conductor (V) and third phase conductor (W) is connected to the busbars (11,12) of the second section (13"), - and in that the phase pairing of third phase conductor (W) and first phase conductor (U) is connected to the busbars (11,12) of the third section (13‴).

3. The baking device according to claim 1 or 2, characterised - in that insulators (21) are provided which electrically isolate the busbars (11,12) of one section of the busbar pair (10) from the busbars (11,12) of the adjacent section (13) extending along the course of the busbar pair (10), - the insulators (21) being preferably adapted to the shape of the busbars (11,12) and connecting two adjacent busbars (11, 12) flush with each other, - in particular in that the insulators (21) are dimensioned along the course of the busbar pair (10) at least such that a short circuit and / or an electric arc between two adjacent sections (13) of the respective busbar (11,12) is prevented when the sliding contacts (20) pass over them.

4. The baking device according to one of claims 1 to 3, characterised in that at least two 3-phase AC power sources (14', 14") are provided, the 3-phase AC power sources (14', 14") being in particular the outputs of two different 3-phase inverters (15).

5. The baking device according to one of claims 1 to 4, characterised - in that two busbar pairs (10',10") that are in parallel to one another are provided, - the first busbar pair (10') supplying power to all lower baking plates (2), - and the second busbar pair (10") supplying power to all upper baking plates (3).

6. The baking device according to claim 5, characterised - in that both busbar pairs (10',10") are supplied by the same 3-phase AC power source (14), - or in that each busbar pair (10', 10") is supplied by a dedicated 3-phase AC power source (14', 14").

7. The baking device according to one of claims 4 to 6, characterised in - that the busbar pair (10) or the busbar pairs (10',10") each have at least six sections (13), - different phase-conductor pairings of a first 3-phase AC power source (14') being connected to the busbars (11,12) of three sections (13), - and the different phase-conductor pairings of a second 3-phase AC power source (14") being connected to the busbars (11,12) of the other three sections (13), - and, in case further sections (13) are provided, the different phase-conductor pairings being connected to at least one further 3-phase AC power source.

8. The baking device according to claim 7, characterised - in that six sections (13', 13", 13‴, 13ʺʺ, 13ʺʺ′, 13""") are provided, - in that the phase pairing of first phase conductor (U') and second phase conductor (V') of the first 3-phase AC power source (14') is connected to the busbars (11, 12) of the first section (13'), - in that the phase pairing of second phase conductor (V') and third phase conductor (W') of the first 3-phase AC power source (14') is connected to the busbars (11, 12) of the second section (13"), - in that the phase pairing of third phase conductor (W') and first phase conductor (U') of the first 3-phase AC power source (14') is connected to the busbars (11,12) of the third section (13‴), - in that the phase pairing of first phase conductor (U") and second phase conductor (V") of the second 3-phase AC power source (14") is connected to the busbars (11,12) of the fourth section (13ʺʺ), - in that the phase pairing of second phase conductor (V") and third phase conductor (W") of the second 3-phase AC power source (14") is connected to the busbars (11,12) of the fifth section (13ʺʺ′), - and in that the phase pairing of third phase conductor (W") and first phase conductor (U') of the second 3-phase AC power source (14") is connected to the busbars (11, 12) of the sixth section (13""").

9. The baking device according to one of claims 4 to 8, characterised - in that the two 3-phase AC power sources (14',14") supply the busbars (11,12) with different, in particular selectable, electrical powers, - and in particular in that the baking plate devices (1) in the region of the first sections (13', 13", 13‴) of the first 3 phase AC power source (14') are heated with a different heating power than the baking plate devices in the region of the sections (13ʺʺ, 13ʺʺ′, 13‴‴) of the second 3-phase AC power source (14").

10. The baking device according to claim 9, characterised - in that the first 3-phase AC power source (14',14") is connected to three sections (13) that are adjacent to one another along the course of the busbar pair (10), - in that the second 3-phase AC power source (14',14") is connected to three sections (13) that are adjacent to one another along the course of the busbar pair (10), - and in that thereby two different heating zones located one after the other are formed along the course of the busbar pair (10).

11. The baking device according to one of claims 1 to 10, characterised in that each baking plate (2, 3) is supplied with power only by a single section (13).

12. The baking device according to one of claims 1 to 11, characterised - in that all sections (13) where different phase-conductor pairs of a 3-phase AC power source (14) are connected to the two busbars (11,12), have the same length, - and / or in that all sections (13) where different phase-conductor pairs of a 3-phase AC power source (14) are connected to the two busbars (11,12), supply the same number of baking plates (2, 3) with electrical power.

13. The baking device according to one of claims 1 to 12, characterised - in that the busbar pair (10) has a measuring section (16), - and in that a measuring equipment (17) is provided in the measuring section (16), which measures electrical parameters of the baking plates (2,3), such as in particular the electrical resistance of the heater (19) of the baking plates (2, 3) and / or the electrical resistance or insulation to ground.

14. The baking device according to claim 13, characterised - in that the measuring equipment (17) continuously records, preferably with each pass, parameters of the baking plates (2,3) conveyed through the measuring section (16), - in particular in that a database (18) is provided, in which the recorded parameters of the measuring equipment (17) are stored and optionally assigned to a value identifying the baking plate (2,3).

15. The baking device according to claim 13 or 14, characterised in that the measuring section (16) is provided in addition to the current-carrying sections (13) of the busbar pair (10) or the busbar pairs (10',10").