WO2009114348A1

WO2009114348A1 - Conveyor dishwasher and method of operating a conveyor dishwasher

Info

Publication number: WO2009114348A1
Application number: PCT/US2009/035954
Authority: WO
Inventors: Dietrich Berner; Harald Disch; Klaus Padtberg; Martin Schrempp
Original assignee: Premark Feg L.L.C.
Priority date: 2008-03-14
Filing date: 2009-03-04
Publication date: 2009-09-17
Also published as: DE102008014319A1; WO2009114348A8

Abstract

A conveyor dishwasher (1) for cleaning wash ware, the conveyor dishwasher (1) having at least one wash zone (6, 7, 8, 9), at least one final-rinse zone (10) and at least one drying zone (26) and also a control arrangement (36). Effective drying of the wash ware which is to be treated in the drying zone (26) while at the same time reducing the energy which has to be expended, is achieved using a wash- ware detector (34) which can sense automatically the type of wash ware which is to be treated. The control arrangement (36) is designed to select automatically a previously defined or definable treatment programme in the drying zone (26) and to set the process parameters associated with the treatment programme selected, depending on the type of wash ware sensed.

Description

CONVEYOR DISHWASHER AND METHOD OF OPERATING A CONVEYOR DISHWASHER

The invention relates to a conveyor dishwasher and to a method of operating such a conveyor dishwasher.

Accordingly, the invention relates, in particular, to a flight-type conveyor dishwasher (warewasher) or a rack conveyor dishwasher (warewasher) .

Conveyor dishwashers (warewashers) are used commercially. In contrast to domestic dishwashers, in which the wash ware which is to be cleaned remains stationary in the machine as it is cleaned, the wash ware in conveyor dishwashers is transported through various treatment zones of the conveyor dishwasher .

In the case of conveyor dishwashers, the wash ware, for example crockery, pots, glasses, cutlery and other articles which are to be cleaned, is conveyed through a number of treatment zones, for example prewash zone(s) , main wash zone(s), pre-rinse zone(s), rinse zone(s) and drying zone(s) . However, different types of wash ware, on account of their final usage, their degree of soiling, their shape and the material used, require different treatment parameters for the individual process steps. Conveyor dishwashers nowadays, however, do not usually differentiate automatically between the types of wash ware, in which case the conventional systems are often designed, as a compromise, such that they can be used for a number of different types of wash ware.

US 6,530,996 B2 describes a rack conveyor dishwasher in which the wash ware which is to be cleaned is fed to the respective treatment zones of the rack conveyor dishwasher in a state in which it is pre-sorted in racks. This conventional conveyor dishwasher provides sensors which can determine the type of wash ware which is to be cleaned by virtue of an identifying feature provided on the rack being sensed. A suitable (dish) washing programme of the conveyor dishwasher is selected in dependence on the identifying feature sensed.

DE 196 08 030 Cl discloses a further conveyor dishwasher in which, depending on the type and soiling of the wash ware which is to be cleaned in the individual treatment zones of the conveyor dishwasher, additional spray systems are switched on or off in order to change the distance in the treatment zones over which the wash ware is subjected to action .

It is already known in the case of a conveyor dishwasher from DE 10 2005 021 101 Al for additional spray nozzles to be switched on and off in dependence on the transporting speed of the wash ware in the dishwashing zone of the conveyor dishwasher, in order thus to reduce the water consumption for final-rinse purposes. Sensors which sense the presence of wash ware at the entrance to the conveyor dishwasher are provided here, the system automatically reducing the transporting speed when the quantity of wash ware passing into the conveyor dishwasher decreases.

The present invention is intended to achieve the object of providing a conveyor dishwasher which has at least one wash zone, at least one final-rinse zone and at least one drying zone and which, despite the reduction in the consumption of energy during operation, provides good drying results for all types of wash ware to be processed. The intention is also to achieve the object of specifying a corresponding method of operating such a conveyor dishwasher.

On the one hand, providing a wash-ware detector makes it possible for the type of wash ware which is to be treated to be sensed automatically. On the other hand, the control arrangement selects a previously defined or definable treatment programme in the drying zone of the conveyor dishwasher and sets the corresponding programme parameters, depending on the determined type of wash ware. In this way, the process parameters of the drying zone can be adapted optimally to the respective wash ware which is to be treated. As a result, the consumption of energy which is used to provide the (heated) air stream used in the drying zone for drying the wash ware can be reduced.

The object on which the invention is based is further achieved by a method of operating a conveyor dishwasher which has at least one drying zone. The invention provides that the method implements the method steps which are specified hereinbelow. In the first instance, the type of wash ware which is to be treated is sensed. Thereafter, a previously defined or definable programme sequence is selected in the drying zone and the corresponding programme parameters are set, depending on the type of wash ware sensed.

Further features of the invention are specified in the dependent patent claims.

The invention will be described hereinbelow with reference to the drawings and using preferred embodiments by way of example .

In the drawings :

Figure 1 shows a schematic view, in longitudinal section, of a conveyor dishwasher according to a first embodiment of the invention; and

Figure 2 shows a schematic view, in longitudinal section, of a conveyor dishwasher according to a second embodiment of the invention. Figure 1 shows a conveyor dishwasher 1 having a transporting arrangement 2 by means of which wash ware (not illustrated in the drawing) is transported in a transporting direction 3 through the conveyor dishwasher 1. The transporting arrangement 2 may be, for example, a conveying belt, which is preferably designed as a multi-part plastic conveying belt and is driven continuously by a preferably electric drive (not illustrated in Figure 1), in which case the wash ware positioned on the conveying belt 2 is conveyed through the various treatment zones 6, 7, 8, 9, 10 and 26 of the conveyor dishwasher 1 in accordance with the illustration in Figure 1. The wash ware transported in the transporting direction 3 is usually positioned on the transporting arrangement, or the conveying belt 2, in the region of the inlet 4. The wash ware is then transported from the inlet 4 into an inlet tunnel 5 in accordance with the transporting direction 3, which is indicated by the arrow.

The conveyor dishwasher 1 according to the first embodiment of the present invention has at least one wash zone, for example, as is illustrated in Figure 1, a prewash zone 6 and also a first main-wash zone 7 and also a second main-wash zone 8, which are arranged downstream of the prewash zone 6 as seen in the transporting direction 3.

In the case of the conveyor dishwasher 1 which is illustrated in Figure 1, the at least one wash zone 6, 7, 8 is followed in the transporting direction 3 by a postwash zone 9 and a final-rinse zone 10, which is arranged downstream of the postwash zone 9.

Figure 1 illustrates the transporting arrangement 2 as a circulating conveying belt. However, it is also conceivable to use, as the transporting arrangement 2, conveying racks into which the wash ware (not illustrated explicitly) is inserted and which are positioned on the top side of the conveying belt. As seen in the transporting direction 3, the wash ware, which is either accommodated directly on the conveying belt 2 or is retained by racks, runs, in the transporting direction 3, through the inlet tunnel 5, the following prewash zone 6, the first main-wash zone 7, the second main-wash zone 8, the postwash zone 9, the final-rinse zone 10 and a drying zone 26 into an outlet section 25.

The abovementioned treatment zones 6, 7, 8, 9 and 10 of the conveyor dishwasher 1 are each assigned spray nozzles 11, 12, 13, 14 and 15 via which liquid is sprayed onto the wash ware which is transported through the respective treatment zones 6, 7 8, 9 and 10 by the transporting arrangement 2. Each treatment zone 6, 7, 8, 9 and 10 is assigned a tank 16, 18, 20 and 22 in which sprayed liquid is accommodated and/or in which liquid for the spray nozzles of the relevant zones is provided. In the case of the conveyor dishwasher 1 which is illustrated in Figure 1, final-rinse liquid in the form of clean water, which may be pure or mixed with further additives, for example rinse aid, is sprayed onto the wash ware (not illustrated in the drawings) via the spray nozzles 15 of the final-rinse zone 10, which are arranged laterally or above and beneath the conveying belt.

Some of the final-rinse liquid sprayed is transported from zone to zone, counter to the transporting direction 3 of the wash ware, via a cascade system. The rest is channelled directly into the prewash tank 16 via a valve 77 and a bypass line 88.

The final-rinse liquid sprayed is collected in the tank 20 (postwash tank 20) of the postwash zone 9, from which it is delivered to the spray nozzles 14 (postwash nozzles 14) of the postwash zone 9 via a pump system. In the postwash zone 9, wash liquid is rinsed off from the wash ware. The liquid which accumulates here flows into the wash tank 18b of the second main-wash zone 8, is usually provided with a detergent and is sprayed onto the wash ware by a pump system via the nozzles 13 (wash nozzles 13) of the second main-wash zone 8. From the wash tank 18b of the second main-wash zone 8, the liquid flows into the wash tank 18a of the first main-wash zone 7. From there, the liquid is sprayed onto the wash ware anew via a further pump system, via the wash nozzles 12 of the first main-wash zone 7. From the wash tank 18a of the first main-wash zone 7, the liquid then flows into the prewash tank 16 of the prewash zone 6. The liquid in the prewash tank 16 is sprayed onto the wash ware via a pump system, via the prewash nozzles 11 of the prewash zone 6, in order for coarse dirt to be removed from the wash ware.

The individual dishwashing systems of the treatment zones 6, 7, 8, 9 and 10 ensure that the wash ware is sprayed both from the top side and from the underside.

The respective zones 6, 7, 8, 9 and 10 of the conveyor dishwasher 1 can be separated from one another via separating curtains 37. In the case of the embodiment which is illustrated in Figure 1, the inlet tunnel 5 itself is also separated from the inlet 4 via a separating curtain 37. The separating curtains 37 prevent wash liquid and final-rinse liquid from spraying between zones and prevent the escape of vapours from the conveyor dishwasher.

The final-rise zone 10 is followed, in the transporting direction 3 of the wash ware, by the already mentioned drying zone 26. In the drying zone 26, the wash ware is dried by way of dry and heated air in order for the moisture located on the wash ware to be blown off and dried up. In order to keep the moisture content of the air in a range which is favourable for drying purposes, it is conceivable, for example, to feed ambient air via an opening, for example through the exit opening for the wash ware. The hot and moisture-laden air is withdrawn from the drying zone 26 via a further opening, for example with the aid of a fan 31. It is advantageous here if the exhaust-air stream from the drying zone 26 passes a heat-recovery device 30, in which a condenser may be provided. The heat-recovery device 30 serves for recovering at least some of the heat energy contained in the exhaust air.

In the case of current flight-type/rack conveyor dishwashers, the wash ware is conveyed through a number of treatment zones, for example prewash zones, main-wash zones, postwash zones, final-rinse zones and drying zones. As already indicated, different treatment parameters are required by different types of wash ware in the treatment zones of the conveyor dishwasher. The conveyor dishwashers which are known at present, however, do not differentiate automatically between the types of wash ware which are to be treated, in which case the conventional systems are usually designed, as a compromise, such that they can be used more or less efficiently for a number of types of wash ware. Especially in the case of treatment of the wash ware in the drying zone, this approach means that usually significantly more energy than would actually be necessary is used in order to dry the wash ware.

The conveyor dishwasher 1 according to the invention - as is illustrated, for example, in Figure 1 - is characterized in that a wash-ware detector 34 is provided, and this serves to directly sense the type of wash ware which is to be treated in the conveyor dishwasher 1. The term "wash-ware detector" used here is to be understood as any detector which is designed to sense and/or to determine the type of wash ware which is to be treated in the conveyor dishwasher. It is conceivable here, in particular, for the wash-ware detector 34 to have at least one detector device 35 which can sense the size, the shape and/or the material of the wash ware which is to be treated in the conveyor dishwasher 1. In a preferred realization of the conveyor dishwasher 1 according to the invention, the wash-ware detector 34 has at least one preferably optically, inductively or capacitively operating detector device, in which case the size, the shape and/or the material of the wash ware can be sensed for the purpose of identifying the type of wash ware. The detector device 35, however, may also be formed by other types of detector, for example inductively operating proximity sensors, light sensors, light curtains, laser scanners, 3D lasers, cameras, rotary transducers, etc.

The wash-ware detector 34 is preferably arranged at the inlet 4 of the conveyor dishwasher 1, in order for it to be possible to sense the type of wash ware which is to be fed to the individual treatment zones 6, 7, 8, 9, 10 and 26 of the conveyor dishwasher 1. It would, of course, also be conceivable, however, for the wash-ware detector 34 to be arranged in the interior of the conveyor dishwasher 1. It is important for the wash-ware detector 34 to be arranged at least upstream of the inlet into the drying zone 26.

The conveyor dishwasher 1 according to the present invention also has a control arrangement 36, which is illustrated schematically in Figure 1. The control arrangement 36 is designed to activate the various activatable components of the conveyor dishwasher 1, for example the respective pumps and valves, in accordance with a previously defined or definable programme sequence, in order for it thus to be possible to set the process parameters in the individual treatment zones 6, 7, 8, 9, 10 and 26 of the conveyor dishwasher 1.

As is illustrated, the control arrangement 36 is connected to the wash-ware detector 34 in particular via a suitable communication connection, in order for the type or nature of wash ware which is sensed by the wash-ware detector 34 as it is fed to the conveyor dishwasher 1 to be interrogated continuously or at predetermined times and/or as predetermined events occur.

The control arrangement 36 is designed such that the wash ware which is to be treated can be detected automatically with reference to the type of wash ware sensed by the wash- ware detector 34. The control arrangement 36 can preferably detect at least the following wash ware automatically:

plates produced from porcelain or a porcelain-like material; cups produced from porcelain or a porcelain-like material, glass or a glass-like material; bowls produced from porcelain or a porcelain-like material, glass or a glass-like material; trays, or tray-like articles, produced from a plastic material; containers, in particular GN containers, produced from a metal, in particular from stainless steel; pots produced from a metal, in particular from stainless steel; pans produced from a metal, in particular from stainless steel; cutlery or items of cutlery produced from a metal, in particular from stainless steel; and drinking glasses produced from glass or a glass-like material .

For the case where the control arrangement 36 does not detect the wash ware with reference to the type of wash ware sensed by the wash-ware detector 34, the relevant wash ware is identified as "other wash ware".

The solution according to the invention is distinguished not just by the automatic identification or detection of the wash ware which is to be treated, but also by the additional functionality of the control arrangement 36, according to which this control arrangement is designed to select automatically a defined (previously or user definable) treatment programme in the drying zone 26 and to set the process parameters of the treatment programme selected by corresponding activation of a dryer controller (not illustrated in Figure 1), depending on the type of wash ware sensed.

To this end, it is conceivable for the control arrangement 36 to have, for example, a storage device (not explicitly illustrated in Figure 1) which can be accessed by the control arrangement 36 and which stores, for the individual types of wash ware in question, optimally adapted treatment programmes and corresponding process parameters for the operation of the drying zone 26.

In this case, the invention is based on the finding that, in conventional conveyor dishwashers, the wash ware is often "over-treated" in the drying zone. Even a lower volume-flow quantity of drying air circulating in the drying zone per unit of time and/or a lower temperature of the drying air is often sufficient to achieve a satisfactory drying result.

In particular, it has been found in the present case that wash ware which is produced, for example, from porcelain or a porcelain-like material can also be completely and effectively dried by air which is colder than the temperature of the air stream usually used in the drying zone for drying the wash ware and at relatively lower air speeds. In this case, use is made of the finding that porcelain or a porcelain-like material has a high self-drying effect compared to other wash-ware materials, in particular to a plastic material and to a metal, on account of its physical properties (ratio of material density, specific heating capacity and thermal conductivity) . Accordingly, the phenomenon that the energy required for evaporation drying comes largely from the energy stored during cleaning generally with hot cleaning solution and does not have to be additionally generated by hot air in the drying zone 26 can be utilized to dry porcelain-like wash ware .

Secondly, it has been found that higher drying-air temperatures and drying-air speeds are required in order to achieve good drying results for wash ware which is composed of a plastic material, in particular for trays or tray-like articles which are composed of a plastic material, compared to wash ware formed from porcelain or a porcelain-like material. The reason for this is that, with wash ware which is composed of a plastic material, the thermal energy cannot be absorbed quickly enough since plastic materials of this type are, as is known, good thermal insulators.

It has also been found that wash ware which is composed of metal, in particular of stainless steel, likewise requires higher drying-air temperatures and drying-air speeds compared to wash ware which is composed of porcelain or a porcelain- like material since the material of wash ware of this type is distinguished by high thermal conductivity and low thermal capacity and therefore exhibits relatively poor self-drying behaviour .

The different self-drying behaviour of the types of wash ware which are to be treated is taken into account by the provision of the control arrangement 36 in the conveyor dishwasher 1 according to the invention. Specifically, provision is made here for the control arrangement 36 to select a treatment programme, which is optimum with regard to the type of wash ware, in the drying zone 26 and to set the process parameters of the treatment programme selected, depending on the type of wash ware previously sensed. This applies with regard to the temperature of the air stream used in the drying zone 26 to dry the wash ware and/or with regard to the volume-flow quantity, which circulates in the drying zone per unit of time, of the air stream used to dry the wash ware .

Accordingly, in the preferred embodiment of the conveyor dishwasher 1 according to the invention illustrated in Figure 1, the control arrangement 36 is signal-connected to a dryer controller of the dryer fan 27, in order, by suitable activation of the dryer fan 27, to set the temperature and/or the flow rate of the air stream used to dry the wash ware in the drying zone 26 with regard to the process parameters which are optimum for the type of wash ware which is to be treated. It goes without saying that it is also conceivable for the control arrangement 36 to be used to regulate the air supply into the drying zone 26 via the opening, in order to set the process parameters, which are optimum with regard to the type of wash ware which is to be treated, in the drying zone 26.

It is likewise conceivable for suitable sensors (not illustrated in Figure 1) , in particular temperature sensors and/or air-flow sensors, to be arranged in the drying zone 26 in order to sense the actual process parameters which prevail in the drying zone 26. These process parameters which actually prevail in the drying zone 26 are to be transmitted, for example via a suitable communication connection, to the control arrangement 36, so that the control arrangement 36 can compare the sensed process parameters with the prespecified process parameters and carry out a suitable regulation operation.

The treatment programmes which can be selected by the control arrangement 36 with regard to the type of wash ware which is to be treated are preferably stored in the abovementioned storage device which is part of the control arrangement 36. In this case, the said treatment programmes may be previously defined treatment programmes. However, it goes without saying that it is also conceivable for the treatment programmes stored in this storage device to be defined or definable by the operator of the conveyor dishwasher 1.

When an optimum treatment programme is selected, and in particular when an optimum drying temperature and/or an optimum air-flow rate are selected in the drying zone 26, primarily the material and therefore the self-drying behaviour of the wash ware which is to be treated play a critical role - as mentioned above. It has been found that the shape of the wash ware which is to be treated (to be dried) also has an effect on the drying behaviour. It has therefore been found that drinking glasses which are produced from glass or a glass-like material and exhibit a relatively good self-drying behaviour on account of their material, require, in order to be effectively dried in the drying zone 26, a higher air-stream temperature than a type of wash ware formed from porcelain or a porcelain-like material, in particular plates, cups and bowls, in the drying zone 26 of the conveyor dishwasher 1 on account of their shape, and in particular on account of their cup shape.

In order to be able to take these different aspects into account when selecting the optimum programme parameters which are to be used in the drying zone 26, the control arrangement 36 used in the conveyor dishwasher 1 according to the invention is also preferably designed to assign a previously defined wash-ware group to each individual type of wash ware sensed with the aid of the wash-ware detector 34. Each wash- ware group is assigned a defined treatment programme according to which the types of wash ware assigned to a specific wash-ware group are treated in the drying zone 26.

In order to accordingly be able to take into account firstly the shape of the wash ware which is to be treated and secondly the material of the wash ware which is to be treated when selecting the process parameters which are optimum for drying, the control arrangement 36 which is used in a preferred realization of the conveyor dishwasher 1 according to the invention can detect the following wash ware:

plates produced from porcelain and a porcelain-like material, cups and bowls produced from porcelain, a porcelain-like material, glass or a glass-like material and other wash ware are assigned to a first wash-ware group; containers, in particular GN containers, pots and pans produced from a metal, in particular from stainless steel, are assigned to a second wash group; trays, and tray-like articles, produced from a plastic material are assigned to a third wash-ware group; drinking glasses produced from glass or a glass-like material are assigned to a fourth wash-ware group; and cutlery and items of cutlery produced from a metal, in particular from stainless steel, are assigned to a fifth wash-ware group.

Effective drying in the drying zone 26 together with a reduced energy requirement is achieved when a relatively low air-stream temperature of, for example, less than 55°C and a medium volume-flow rate of, for example, less than 2500 m³/h are selected in the drying zone 26 for drying a type of wash ware assigned to the first wash-ware group. For types of wash ware which are assigned to the third wash-ware group, the temperature of the air stream is to be set to an increased value of, for example, greater than 65°C and the volume-flow rate is to be set to an increased value of, for example, greater than 2500 m³/h as optimum process parameters in the drying zone 26. A medium air-stream temperature of, for example, 55°C to 65°C and a relatively high volume-flow rate of, for example, greater than 2500 m³/h are to be set for effective drying of types of wash ware which are assigned to the second or to the fifth wash-ware group. A type of wash ware which is classified in the fourth wash-ware group is preferably to be dried at a medium air-stream temperature of, for example, 55°C to 65°C and at a medium volume-flow rate of, for example, less than 2500 m³/h.

The values mentioned above are examples, which are not to be considered as restrictive.

It is also optionally conceivable for the control arrangement 36 used in the conveyor dishwasher 1 according to the invention to be designed not only to set automatically the process parameters which prevail in the drying zone 26 of the conveyor dishwasher 1 depending on the determined type of wash ware, but also to select and adjust automatically a previously defined or definable drying time for the wash ware of the determined type of wash ware in the drying zone 26 depending on the determined type of wash ware. The drying time can be set, for example, by suitable selection of the transporting speed of the wash ware which is to be treated. To this end, the control arrangement 36 is connected to the electric drive (not illustrated in Figure 1) of the transporting arrangement 2 via a corresponding signal line, so that the conveying belt drive can be suitably activated.

The solution according to the invention permits automatic detection of the type of wash ware which is to be treated and also automatic setting of programme parameters, which are optimally adapted to the type of wash ware, in the drying zone. In this case, provision is made for the control arrangement to select, and correspondingly define, optionally automatically the process parameters which are optimum with regard to the type of wash ware, in order to make it possible, in principle, for the user of the conveyor dishwasher to be capable of manually setting or altering the process parameters which prevail in the drying zone of the conveyor dishwasher.

Figure 2 illustrates a schematic side view of a second embodiment of the conveyor dishwasher according to the invention. The conveyor dishwasher 1 according to Figure 2 differs from the embodiment described previously with reference to Figure 1 in that just one main-wash zone is provided in the second embodiment. The rest of the conveyor dishwasher 1 according to Figure 2 is constructed identically to the conveyor dishwasher which is illustrated in Figure 1, in which case reference can be made here to the description relating to Figure 1.

The invention is not restricted to the embodiments of Figures 1 and 2, which are shown by way of example in the drawings. Rather, the invention can be gathered from an overall expert view of the patent claims and of the description of the exemplary embodiments.

Claims

Patent Claims

1. Conveyor dishwasher for dishwashing wash ware, the conveyor dishwasher having at least one wash zone (6, 7, 8) , at least one final-rinse zone (10) and at least one drying zone (26) and also a control arrangement (36) , characterized in that a wash-ware detector (34) is provided and is designed to sense the type of wash ware which is to be treated; and in that the control arrangement (36) is designed to select automatically a previously defined or definable treatment programme at least in the drying zone (26) and to set the process parameters associated with the treatment programme selected, depending on the sensed type of wash ware which is to be treated.

2. Conveyor dishwasher according to Claim 1, characterized in that the wash-ware detector (34) has at least one optically operating detector device (35) which is designed to sense the size of the wash ware which is to be treated and/or which is designed to sense the shape of the wash ware which is to be treated.

3. Conveyor dishwasher according to Claim 1 or 2, characterized in that the wash-ware detector (34) has at least one inductively or capacitively operating detector device (35) which is designed to sense the material of the wash ware which is to be treated.

4. Conveyor dishwasher according to one of the preceding claims, characterized in that the control arrangement (36) is designed to set automatically to a previously defined or definable value the temperature of an air stream which is used in the drying zone (26) for drying the wash ware, depending on the type of wash ware sensed, and/or in that the control arrangement (36) is designed to set automatically to a previously defined or definable value a volume-flow quantity, which is employed per unit of time, of an air stream which is used in the drying zone (26) for drying the wash ware, depending on the type of wash ware sensed .

5. Conveyor dishwasher according to one of the preceding claims, characterized in that the control arrangement (36) is designed to set optionally automatically the process parameters for the drying zone (26) associated with the treatment programme selected.

6. Conveyor dishwasher according to one of the preceding claims, characterized in that the control arrangement (36) is designed to detect the following wash ware with reference to the type of wash ware sensed: plates produced from porcelain or a porcelain-like material; cups produced from porcelain or a porcelain-like material, glass or a glass-like material; bowls produced from porcelain or a porcelain-like material, glass or a glass-like material; trays, or tray-like articles, produced from a plastic material; containers, in particular GN containers, produced from a metal, in particular from stainless steel; pots produced from a metal, in particular from stainless steel; pans produced from a metal, in particular from stainless steel; cutlery or items of cutlery produced from a metal, in particular from stainless steel; and/or drinking glasses produced from glass or a glass-like material .

7. Conveyor dishwasher according to Claim 6, characterized in that the control arrangement (36) is designed to assign each item of wash ware detected to a previously defined or definable wash-ware group, and in that the control arrangement (36) is also designed to select automatically, for each wash-ware group, a previously defined or definable treatment programme by which the wash ware assigned to the wash-ware group is to be treated in the drying zone (26), and to set the process parameters associated with the treatment programme selected.

8. Conveyor dishwasher according to Claim 7, characterized in that the control arrangement (36) is designed to assign the following wash ware to a first wash-ware group: plates produced from porcelain or from a porcelain-like material and plates and bowls produced from porcelain, a porcelain-like material, glass or a glass-like material; and/or in that the control arrangement (36) is designed to assign the following wash ware to a second wash-ware group: containers, in particular GN containers, pots and pans produced from a metal, in particular from stainless steel; and/or in that the control arrangement (36) is designed to assign the following wash ware to a third wash-ware group; trays, or tray-like articles, produced from a plastic material; and/or in that the control arrangement (36) is designed to assign the following wash ware to a fourth wash-ware group: drinking glasses produced from glass or a glass-like material; and/or in that the control arrangement (36) is designed to assign the following wash ware to a fifth wash-ware group: cutlery and items of cutlery produced from a metal, in particular from stainless steel.

9. Conveyor dishwasher according to Claim 8, characterized in that the control arrangement (36) is designed to set automatically to a previously defined or definable first value, as it detects wash ware belonging to the first wash- ware group, the temperature of an air stream which is used in the drying zone (26) for drying the wash ware, and to set to a previously defined or definable first value a volume-flow quantity, which is employed per unit of time, of the air stream which is used in the drying zone (26) for drying the wash ware; and/or in that the control arrangement (36) is designed to set automatically to a previously defined or definable second value, as it detects wash ware belonging to the second or to the fifth wash-ware group, the temperature of an air stream which is used in the drying zone (26) for drying the wash ware, and to set to a previously defined or definable second value a volume-flow quantity, which is employed per unit of time, of the air stream which is used in the drying zone (26) for drying the wash ware; and/or in that the control arrangement (36) is designed to set automatically to a previously defined or definable third value, as it detects wash ware belonging to the third wash- ware group, the temperature of an air stream which is used in the drying zone (26) for drying the wash ware, and to set to a previously defined or definable second value a volume-flow quantity, which is employed per unit of time, of the air stream which is used in the drying zone (26) for drying the wash ware; and/or in that the control arrangement (36) is designed to set automatically to a previously defined or definable second value, as it detects wash ware belonging to the fourth wash- ware group, the temperature of an air stream which is used in the drying zone (26) for drying the wash ware, and to set to a previously defined or definable first value a volume-flow quantity, which is employed per unit of time, of the air stream which is used in the drying zone (26) for drying the wash ware.

10. Conveyor dishwasher according to Claim 9, characterized in that the first temperature value is lower than the second temperature value, and in that the second temperature value is lower than the third temperature value; and in that the first value of the volume-flow quantity which is employed per unit of time is lower than the second value of the volume-flow quantity which is employed per unit of time.

11. Conveyor dishwasher according to one of the preceding claims, characterized in that the control arrangement (36) is designed to select automatically a previously defined or definable drying time in the drying zone (26) and to set the drying time selected by suitable selection of the transporting speed of the wash ware which is to be treated, depending on the type of wash ware sensed.

12. Conveyor dishwasher according to Claim 11, characterized in that the control arrangement (36) is designed to set to a previously defined or definable value, as it detects a type of wash ware which includes containers, in particular GN containers, pots or pans, produced from a metal, in particular from stainless steel, the drying time in the drying zone (26) , which value is greater than the value of the drying time which is set as it detects a type of wash ware which includes another item of wash ware.

13. Conveyor dishwasher according to Claim 11 or 12, characterized in that the control arrangement (36) is designed to set optionally automatically the drying time selected by suitable selection of the transporting speed of the wash ware which is to be treated.

14. Method of operating a conveyor dishwasher (1) for dishwashing wash ware, the conveyor dishwasher (1) having at least one wash zone (6, 7, 8), at least one final-rinse zone (9, 10) and at least one drying zone (26), characterized in that the method has the following method steps: i) the type of wash ware which is to be treated is sensed; ii) a previously defined or definable programme sequence is selected in the drying zone (26) depending on the type of wash ware sensed; and iii) the process parameters associated with the treatment programme selected are set.

15. Method according to Claim 14, characterized in that the type of wash ware is sensed by detection of the size, by detection of the shape and/or by detection of the material of the wash ware which is to be treated.

16. Method according to Claim 14 or 15, characterized in that method step iii) has the following method steps: iii.l) each type of wash ware sensed is assigned to a previously defined or definable wash-ware group; iii.2) a previously defined or definable treatment programme, according to which the type of wash ware assigned to the wash-ware group is to be treated in the drying zone (26), is selected for each wash-ware group; and iii.3) the process parameters associated with the treatment programme selected are set.

17. Method according to one of Claims 14 to 16, characterized in that the method also has the following method step after method step ii) : the drying time in the drying zone (26) is set depending on the type of wash ware sensed, by the advancing speed of the wash ware which is to be treated being selected accordingly.