DISHWASHER WITH DIRT DISPENSING SYSTEM

Description

[0001] The invention relates generally to the field of commercial dishwashing.

[0002] In particular, the invention relates to a dishwasher according to the preamble of patent claim 1. Accordingly, the invention relates in particular to a commercial dishwashing or utensil washing machine which is designed as a programmer or as a conveyor dishwasher.

[0003] The invention is thus directed to a dishwasher having at least one wash zone configured as a recirculation circuit. The wash zone configured as a recirculation circuit has a nozzle system with at least one wash nozzle for spraying wash liquid onto the items to be cleaned, a wash tank for collecting at least a portion of the sprayed wash liquid, and a wash pump for supplying wash liquid collected in the wash tank to the at least one wash nozzle. Furthermore, the dishwasher has a dirt collection system associated with the at least one wash zone, comprising at least one tank cover sieve, for separating dirt particles from the sprayed wash liquid flowing back into the wash tank by gravity. Such dishwashers are known, for example, from the respective documents DE 10 2005 008 987 B3, DE 10 2011 084917 A1, US 2011 / 197934 A1, and CN 113 940 601 A.

[0004] Box-type ware washers are manually loaded and unloaded dishwashers. These box-type ware washers, also called batch ware washers, can be pass-through dishwashers, also called hood-type ware washers, or front-loaders. Front-loaders can be under-counter machines, top-counter machines, or free-standing front-loading dishwashers.

[0005] A dishwasher designed as a programmable automatic dishwasher typically has a treatment chamber for cleaning dishes. A wash tank is usually located below the treatment chamber, into which liquid from the treatment chamber can flow back by gravity. The wash tank contains wash liquid, which is usually water, to which detergent can be added if necessary.

[0006] A dishwasher designed as a programmable automatic dishwasher further comprises a wash system with a wash pump, a pipe system connected to the wash pump, and a nozzle system with at least one wash nozzle. The wash liquid in the wash tank can be pumped from the wash pump via the pipe system to the at least one wash nozzle, and sprayed onto the items to be cleaned by this at least one wash nozzle in the treatment chamber. The sprayed wash liquid then flows back into the wash tank by gravity.

[0007] Conveyer ware washers are primarily flight-type ware washers or rack-type ware washers. Conveyer ware washers are typically used in commercial applications. Unlike programmable dishwashers, where the ware remains stationary in the machine during cleaning, conveyor ware washers transport the ware through various treatment zones.

[0008] A conveyor dishwasher usually has at least one pre-wash zone and at least one main wash zone, which is arranged after the pre-wash zone(s) in the direction of transport of the wash items. Viewed in the direction of transport after the main wash zone(s) there is usually at least one final wash zone or pre-rinse zone and at least one final rinse zone downstream of the final wash zone(s). Viewed in the direction of transport, the wash items, which are either picked up directly on the conveyor belt or held by baskets, usually run through an inlet tunnel, the subsequent pre-wash zone(s), main wash zone(s), final wash zone(s), final rinse zone(s), and a drying zone into an outlet section.

[0009] Each of the aforementioned wash zones of the conveyor dishwasher is assigned a wash system comprising a wash pump and a line system (wash line system) connected to the wash pump, via which wash liquid is supplied to the nozzle system or to the at least one wash nozzle of the nozzle system. The wash liquid supplied to the at least one wash nozzle of the nozzle system is sprayed onto the washware in the respective wash zones of the conveyor dishwasher, which is transported through the respective wash zones by a transport device of the conveyor dishwasher. Each wash zone is assigned a reservoir in which the liquid sprayed by the wash nozzles is collected and / or in which liquid is provided for the nozzle systems of the respective treatment zones.

[0010] In conventional conveyor dishwashers, rinse aid in the form of fresh water, which can be pure or mixed with other additives such as rinse aid, is sprayed onto the washware via the spray nozzles in the rinse zone. At least a portion of the sprayed rinse aid is transported from zone to zone via a cascade system, counter to the direction of the washware's transport.

[0011] The sprayed final rinse liquid is collected in a tank (post-wash tank) in the post-wash zone, from which it is pumped to the spray nozzles (post-wash nozzles) of the post-wash zone via the wash pump of the wash system belonging to the post-wash zone. In the post-wash zone, wash liquid is rinsed off the dishes. The resulting liquid flows into the wash tank of at least one main wash zone, which is located upstream of the post-wash zone in the transport direction of the dishes. Here, the liquid is usually treated with a cleaner and sprayed onto the dishes by a pump system (wash pump) belonging to the wash system of the main wash zone via the nozzles (wash nozzles) of the main wash zone. From the wash tank of the main wash zone, the liquid then flows into the pre-wash tank of the pre-wash zone - unless another main wash zone is provided.The liquid in the pre-wash tank is sprayed onto the dishes via a pump system (pre-wash pump) belonging to the washing system of the pre-wash zone via the pre-wash nozzles of the pre-wash zone in order to remove coarse contaminants from the dishes.

[0012] Dishwashers are typically equipped with rinse pumps that supply the rinse aid to be sprayed into the rinse zone's piping system. This ensures, in particular, a virtually constant volume flow of rinse aid in the rinse zone. However, it is also conceivable to use the on-site line pressure—for example, the fresh water supply pressure—to supply the rinse aid to the piping system of the rinse zone. In this latter case, a controllable valve can be provided between the piping system and the spray nozzles of the rinse zone to temporarily or completely interrupt the supply of rinse aid to the spray nozzles.

[0013] Regardless of whether a dishwasher is designed as a program machine or as a conveyor dishwasher, commercial dishwashers usually comprise at least one washing zone designed as a recirculation circuit, which has a nozzle system with at least one washing nozzle for spraying washing liquid onto the items to be cleaned, a washing tank for collecting at least part of the sprayed washing liquid and a washing pump for supplying liquid collected in the washing tank to the at least one washing nozzle.

[0014] Since a wash zone designed as a recirculation circuit is used to clean the wash ware, at least a portion of the wash liquid already sprayed in the wash zone is circulated, resulting in the risk that the protective particles removed from the wash ware will be increasingly broken down due to the constant circulation of the wash liquid and thus can no longer be easily separated from the wash liquid using sieves, etc. Accordingly, there is a risk that, with a wash zone designed as a recirculation circuit, the dirt load in the wash liquid in the wash zone will increase with increasing wash time, increasing the risk of re-soiling of the wash ware and worsening the overall wash result.

[0015] This problem occurs particularly in the pre-wash or main wash zones of a conveyor-type dishwasher. Since the flow direction of the wash liquid used in conveyor-type dishwashers cascades in the opposite direction to the direction of transport of the items to be cleaned, the dirt concentration of the wash liquid in at least one pre-wash zone is highest compared to the dirt concentration of the wash liquid in the other treatment zones, since the pre-wash zone is where most of the dirt accumulates.

[0016] On the other hand, it is unavoidable that, over the course of a conveyor-type dishwasher's operation, some of the more heavily soiled wash liquid from the pre-wash zone is "carried over" into at least one main wash zone downstream of the pre-wash zone as the wash ware is transported. This increases the soil load in the wash liquid in the main wash zone and, consequently, can also deteriorate the wash results in the main wash zone.

[0017] To separate the dirt particles introduced into the dishwasher from the wash liquid used to rinse the dishes, it is generally known to use sieve devices in the form of dirt sieve baskets, in which the dirt particles introduced into the dishwasher are collected. In dishwashers designed as programmable automatic machines, such a dirt sieve basket is usually located in the sump of the treatment chamber above the wash tank.

[0018] On the other hand, with regard to dishwashers designed as conveyor dishwashers, it is known to equip at least the pre-wash tank associated with the pre-wash zone, and preferably also the main wash tank associated with the at least one main wash zone, with surface sieves and dirt sieve baskets.

[0019] During operation of the dishwasher, which is designed either as a programmable automatic or conveyor dishwasher, the dirt particles washed off the washware by the circulating wash water fall due to gravity onto the surface sieves. There, the dirt particles are separated from the wash liquid flowing back into the corresponding wash tank. The separated dirt particles are then typically rinsed into a dirt sieve basket.

[0020] One problem with state-of-the-art automatic dirt removal systems is that, due to their nature, they only have a limited dirt removal capacity. In existing dirt removal systems, the amount of wash water required to pump the dirt particles out of the dirt collection area of ​​the dirt removal system is designed for the fresh water rinse volume of the respective machine type. This is necessary to ensure a balanced water balance within the machine. If more wash water were used to pump out the dirt than the fresh water subsequently supplied to the machine through the fresh water rinse, the water level in the wash tank would drop, and the washing process would then be automatically shut down.

[0021] On the other hand, the higher the amount of dirt introduced, the more wash water is required in principle to pump the introduced dirt out of the machine as completely as possible and thus achieve the best possible dirt removal performance.

[0022] In times of constant efforts to further reduce machine consumption in terms of water, energy and chemicals, a key focus is on the amount of fresh water used for rinsing, as this largely determines the total water consumption of commercial dishwashers.

[0023] Accordingly, there are two opposing goals in commercial dishwashing which conflict with each other with regard to an ideal process flow: Firstly, especially when a high level of dirt is loaded into the dishwasher, a large amount of wash water is required to pump the dirt out of the machine using the automatic dirt removal system. Depending on the type and amount of dirt, the amount of wash water required to pump the dirt out of the machine can be higher even in conventional state-of-the-art dishwashers than is actually available from the fresh water flowing in through the fresh water post-rinse. This limits the performance of the dirt removal system to a certain extent in certain machine types. This is because there is no more water available to pump out the dirt, as otherwise the water level in the wash tank would drop too much.

[0024] On the other hand, the aim remains to further reduce the amount of fresh water used for rinsing, which will of course exacerbate the above-mentioned problem in the long term, as at a certain point there will no longer be enough wash water available to pump out the dirt or to operate the automatic dirt discharge system reliably.

[0025] Based on this problem, the invention is therefore based on the object of developing a dishwasher of the type mentioned at the outset in such a way that the dirt removal performance can be optimized without increasing the amount of fresh water required to operate the dishwasher.

[0026] This object is achieved according to the invention by the subject matter of independent patent claim 1, wherein advantageous developments of the dishwasher according to the invention are specified in the dependent claims.

[0027] Accordingly, the invention relates to a dishwasher designed as a programmable automatic or conveyor dishwasher, and comprising a dirt collection system associated with at least one wash system of the dishwasher. The dirt collection system comprises a dirt collection area arranged at least partially in the wash tank of the dishwasher. The dirt collection area serves to collect the dirt particles separated from the wash liquid by means of a tank cover sieve.

[0028] Furthermore, a dirt discharge system with a dirt discharge pipe system that is fluidly connected to the dirt collection area is provided, via which the dirt collection area of ​​the dishwasher can be emptied, in particular as needed.

[0029] The dishwasher according to the invention is characterized in particular in that a separator device is assigned to the dirt discharge system, which separator device is designed to separate at least a part of the washing liquid required for emptying the dirt collection area and discharged together with the dirt particles from the dirt collection area from the dirt particles discharged from the dirt collection area and to return the separated washing liquid back to the water circuit of the dishwasher.

[0030] This solution provides an automatic dirt removal system for dishwashers in which the amount of dirt and water pumped out is independent of the amount of fresh water flowing in during the rinse cycle. This optimizes the dishwasher's dirt removal performance, as the dirt collection area of ​​the dirt removal system can operate independently of the amount of fresh water supplied to the dishwasher's water circuit per unit of time. At the same time, the recycling of the separated wash liquid ensures that the dishwasher's water consumption cannot be increased.

[0031] According to embodiments of the dishwasher according to the invention, the dirt discharge system is configured with the separator device to feed the wash liquid separated from the dirt particles removed from the dirt collection area back into the wash tank of the dishwasher's washing system, which is equipped with the automatic dirt discharge system. However, particularly in conveyor dishwashers that have several treatment chambers connected in series, it is also conceivable for the wash liquid separated in the separator device to be fed to the wash tank of another treatment zone.

[0032] According to the dishwasher according to the invention, the dirt removal system comprises a dirt removal pump, the suction side of which is fluidly connected or connectable to the dirt collection area, and the pressure side of which is fluidly connected or connectable to the separator device. The dishwasher comprises a control device configured to control the dirt removal pump of the dirt removal system, particularly independently of the inflow of fresh water into the dishwasher's water circuit.

[0033] In other words, with the solution according to the invention, the dirt removal system can actually be activated whenever the degree of soiling of the washing liquid has reached a critical level, whereby in particular it is not necessary to pay attention to whether a sufficient amount of fresh water is also fed back into the water circuit of the dishwasher.

[0034] In a further development of the latter aspect, the dishwasher comprises a sensor system configured to detect a degree of soiling of the washing liquid, preferably in the at least one wash tank of the dishwasher, and / or to detect a soil load of the items to be treated in the dishwasher. In particular, the control device is configured to control the soil discharge pump of the soil discharge system depending on the detected degree of soiling of the washing liquid and / or depending on the detected soil load of the items to be treated in the dishwasher.

[0035] A suitable sensor, for example, could be a turbidity sensor that detects the degree of soiling in the wash liquid. Alternatively or in addition to this, it is also conceivable to use an optical system, particularly a vision camera system, which measures or detects the soil load directly on the washware.

[0036] In particular, it can be provided that the control device is configured to automatically activate the dirt discharge pump of the dirt discharge system when the sensor system detects that the detected degree of soiling of the washing liquid has reached a predetermined or definable value, and / or when the sensor system detects an increased dirt load in the items to be treated in the dishwasher. Optional automatic or manual activation of the dirt discharge pump of the dirt discharge system is of course also conceivable.

[0037] According to a preferred implementation of the separator device, it is provided that the separator device has a collecting container which is fluidly connected or connectable to the dirt discharge pipe system of the dirt discharge system and to which the washing liquid required for emptying the dirt collection area with the dirt particles from the dirt collection area is supplied when the dirt collection area is emptied.

[0038] Preferably, the collecting container is assigned a sieve system with which at least a portion of the washing liquid required to empty the dirt collection area and discharged together with the dirt particles from the dirt collection area is separated from the dirt particles discharged from the dirt collection area.

[0039] According to a further development of the latter aspect, the separator device is designed to preferably automatically remove the dirt particles separated from the washing liquid in the separator device. In this context, it is conceivable, for example, to remove the dirt particles from the separator device, and in particular from the screening system of the separator device, using a pump, in particular a screw conveyor pump.

[0040] According to further developments of the separator device, an overflow system is provided for the collecting container of the separator device, which connects the collecting container to an on-site drain or to the wash tank of the dishwasher. This provides redundancy should the return of the separated wash liquid from the separator device to the dishwasher's water circuit be disrupted or interrupted.

[0041] Preferably, the separator device is assigned a waste water pump which is designed, in particular as needed, to feed the washing liquid separated in the separator device back into the circuit of the dishwasher at predetermined times and / or events or continuously.

[0042] In this context, it is particularly conceivable that the separator device is assigned a sensor system which is designed to detect the quantity of washing liquid separated in the separator device.

[0043] In this context, it is conceivable that a control device is assigned to the separator device, which is designed to control the waste water pump depending on the amount of washing liquid separated from the dirt particles in the separator device.

[0044] In particular, it is advisable that the wastewater pump is controlled cyclically, at least as needed or at predetermined or definable times or events, in particular in such a way that at least partial flushing of the screening system of the separator device can be achieved (if necessary).

[0045] In order to achieve even more efficient dirt separation, according to further developments of the solution according to the invention, the separator device has a filter system which is designed to filter the washing liquid separated from the dirt particles in the separator device before it is returned to the water circuit of the dishwasher.

[0046] According to a further aspect, a heat exchanger system is assigned to the separator device, in order to recover thermal energy, particularly on demand or continuously, from the washing liquid separated from the dirt particles in the separator device. This thermal energy can then be used, for example, to heat the fresh water supplied to the dishwasher.

[0047] The solution according to the invention thus enables regular or continuous soil removal during dishwasher operation without having to extend the dishwasher's running time and without increasing the dishwasher's fresh water consumption. This not only reduces the risk of re-soiling of the washware (since regular or continuous soil removal optimizes the quality of the wash liquid), but also does not negatively impact the dishwasher's capacity.

[0048] The solution according to the invention therefore allows the dirt particles collected in at least one wash zone of the dishwasher by means of the dirt collection system to be continuously and automatically removed from the dishwasher. Such continuous and automatic dirt removal also relieves the burden on the dishwasher's operating personnel. Furthermore, it can effectively prevent the recirculation of the wash liquid in the wash zone from being affected or blocked by overfilling the dirt collection area.

[0049] In the following, embodiments of the solution according to the invention are described in more detail with reference to the accompanying drawings.

[0050] The drawings show: FIG. 1 schematically shows a dishwasher designed in the form of a conveyor dishwasher according to a first embodiment of the invention; and FIG. 2 schematically shows a dishwasher designed in the form of a programmable dishwasher according to a second embodiment of the invention.

[0051] In FIG. 1 An example of a conveyor dishwasher 50 constructed according to the teachings of the present invention is shown in a schematic longitudinal sectional view.

[0052] The conveyor dishwasher 50 as shown in FIG. 1 has a pre-wash zone 51 and a main wash zone 52, which in the transport direction T of the (in FIG. 1 not shown) of the wash ware is arranged after the pre-wash zone 51. Seen in the transport direction T after the main wash zone 52, FIG. 1 The conveyor dishwasher 50 shown has a post-wash or pre-wash zone 53 and a final rinse zone 54 downstream of the post-wash or pre-wash zone 53. The wash ware, which is either picked up directly on a conveyor belt 58 or held by baskets, runs in the transport direction T through an inlet tunnel 55, the adjoining pre-wash zone 51, the main wash zone 52, the post-wash zone 53, the final rinse zone 54 and a drying zone 56 into an outlet section 57.

[0053] The aforementioned treatment zones 51, 52, 53, 54 of the conveyor dishwasher 50 are each assigned spray nozzles 13-1, 13-2, 13-3, 13-4, via which liquid is sprayed onto the wash ware transported by the conveyor belt 58 through the respective treatment zones 51, 52, 53, 54. At least the pre-wash zone 51, the main wash zone 52, and the post-wash or pre-rinse zone 53 are each assigned a tank (wash tank 14-1, 14-2, 14-3), in which sprayed wash liquid is collected and / or wash liquid is provided for the spray nozzles 13-1, 13-2, 13-3 of the respective zones 51, 52, 53.

[0054] The pre-wash zone 51, the main wash zone 52 and the post-wash zone 53 of the conveyor dishwasher 50 according to the FIG. 1 The first embodiment of the invention shown each has a washing system 10-1, 10-2, 10-3. Each washing system 10-1, 10-2, 10-3 consists of a washing pump 11-1, 11-2, 11-3, a line system 12-1, 12-2, 12-3 connected to the washing pump 11-1, 11-2, 11-3, and the spray nozzles 13-1, 13-2, 13-3 connected to the line system 12-1, 12-2, 12-3.

[0055] Furthermore, a FIG. 1 A schematically illustrated control device 100 is provided which serves (among other things) to suitably control the respective washing pumps 11-1, 11-2, 11-3 of the washing systems 10-1, 10-2, 10-3 during a washing process in order to supply washing liquid, at least temporarily, via the associated line system 12-1, 12-2, 12-3 to the spray nozzles 13-1, 13-2, 13-3 of the nozzle system associated with the respective washing system 10-1, 10-2, 10-3.

[0056] At the FIG. 1 In the conveyor dishwasher 50 shown, rinse aid liquid in the form of fresh water, which may be mixed with further chemical additives such as rinse aid, is sprayed onto the FIG. 1 not shown items are sprayed. As shown in FIG. 1 As shown, laterally arranged spray nozzles 13-5 can be provided in the final rinse zone 54.

[0057] A portion of the rinse liquid sprayed in the rinse zone 54 is transported from zone to zone via a cascade system, counter to the transport direction T of the washware. The remaining portion is directed directly into the pre-wash tank 14-1 of the pre-wash zone 51 via a valve 59 and a bypass line 60.

[0058] The rinse liquid sprayed in the final rinse zone 54 is collected in the tank (post-wash or pre-wash tank 14-3) of the post-wash or pre-wash zone 53, from which it is pumped to the spray nozzles 13-3 (post-wash or pre-wash nozzles) of the post-wash or pre-wash zone 53 via the wash pump 11-3 belonging to the wash system 10-3 of the post-wash or pre-wash zone 53. In the post-wash or pre-wash zone 53, wash liquid is rinsed off the washware.

[0059] The resulting liquid flows into the wash tank 14-2 of the main wash zone 52, is usually provided with a chemical cleaner and is sprayed onto the washware via the spray nozzles 13-2 (wash nozzles) of the wash system 10-2 belonging to the main wash zone 52 with the aid of a wash pump 11-2 belonging to the wash system 10-2 of the main wash zone 52.

[0060] From the wash tank 14-2 of the main wash zone 52, the washing liquid then flows into the pre-wash tank 14-1 of the pre-wash zone 51. The washing liquid collected in the pre-wash tank 14-1 is sprayed onto the washware in the pre-wash zone 51 by means of a wash pump 11-1 belonging to the wash system 10-1 of the pre-wash zone 51 via the spray nozzles 13-1 (pre-wash nozzles) of the wash system 10-1 belonging to the pre-wash zone 51 in order to remove coarse contaminants from the washware.

[0061] At the FIG. 1 In the conveyor dishwasher 50 shown, the main wash zone 52 has a tank cover screen 20-2, which is arranged above the main wash tank 14-2. During operation of the conveyor dishwasher 50, washing liquid is sprayed onto the washware via the spray nozzles 13-2 (wash nozzles) of the wash system 10-2. The sprayed washing liquid flows back into the wash tank 14-2 of the main wash zone 52 by gravity, wherein the dirt particles rinsed from the washware in the main wash zone 52 are retained by the tank cover screen 20-2, provided the dirt particles are larger than the mesh size of the tank cover screen 20-2. The mesh size of the tank cover screen 20-2 is preferably approximately 1 mm to 4 mm.

[0062] At the FIG. 1 In the schematically illustrated conveyor dishwasher 50, the washing operation must be interrupted to clean the tank cover sieve 20-2 in order to be able to clean the tank cover sieve 20-2 manually.

[0063] A portion of the wash liquid sprayed in the main wash zone 52 flows via an overflow system 61 into the wash tank (pre-wash tank 14-1) of the pre-wash zone 51. Like the main wash zone 52, the pre-wash zone 51 is equipped with a tank cover screen 20-1 designed as a flat screen. This tank cover screen 20-1 is arranged above the wash tank (pre-wash tank 14-1) of the pre-wash zone 51 to separate dirt particles from the wash liquid sprayed in the pre-wash zone 51 and flowing back into the pre-wash tank 14-1 by gravity. The mesh size of the tank cover screen 20-1 is preferably in a range between approximately 1 mm and 4 mm.

[0064] Since - as stated at the beginning - the dirt concentration of the washing liquid is greatest in the pre-wash zone 51, since this is where most of the dirt accumulates, the FIG. 1 The conveyor dishwasher 50 shown is equipped with a dirt collection system 70 assigned to the pre-wash zone 51, which has a dirt collection area 71-1 arranged in the pre-wash zone 51, and in particular within the pre-wash tank 14-1.

[0065] The structure and functionality of the FIG. 1 The dirt collection system 70 used in the conveyor dishwasher 50 shown is described below in particular with reference to the illustration in FIG. 2 described in more detail.

[0066] At the FIG. 1 In the illustrated embodiment of the conveyor dishwasher 50, the dirt collection area 71-1 serves to collect the dirt particles separated from the washing liquid by means of the tank cover sieve 20-1. In detail, and as will be explained below with reference to the illustration in FIG. 2 As described in more detail, the dirt collection area 71-1 is designed as an upwardly open chamber arranged in the pre-wash tank 14-1, which can have a pressure equalization system on its sides. The dirt particles separated by the tank cover sieve 20-1 can enter the chamber-shaped dirt collection area 71-1 via the upper opening. Because the dirt collection area 71-1 has a pressure equalization system on its sides, particularly rapid emptying of the dirt collection area 71-1 is possible.

[0067] As explained below with reference to the illustration in FIG. 2 As will be described in more detail, the tank cover sieve 20-1 is arranged above the dirt collection area 71-1 and has a drainage slope in the form of a gradient directed in the direction of a feed opening 22, wherein the upwardly open dirt collection area 71-1 is arranged below the feed opening 22, so that the dirt particles separated with the aid of the tank cover sieve 22 can reach the dirt collection area 71-1 via the feed opening 22.

[0068] It is particularly conceivable that the tank cover screen 20-1 is at least partially funnel-shaped, wherein the supply opening 22 is formed within the funnel-shaped region 21 of the tank cover screen 20-1, and preferably in the zenith of the funnel-shaped region 21 of the tank cover screen 20-1 (cf. in particular the illustration in FIG. 2 ). The FIG. 1 The dirt collection system 70 used in the embodiment shown further comprises a dirt discharge system 70 connected to the dirt collection area 71-1, for example consisting of a standpipe 72-1 and a dirty water line 73-1, for discharging the dirt particles collected in the dirt collection area 71-1 from the pre-wash zone 51.

[0069] As shown, a dirt removal pump 74-1 is arranged in the dirt removal system 70; 72-1, 73-1. The suction-side inlet of the dirt removal pump 74-1 is connected to the lower area of ​​the dirt collection area 71-1 via the standpipe 72-1 belonging to the dirt removal system 70. The pressure-side outlet of the dirt removal pump 74-1 opens into the wastewater line 73-1 belonging to the dirt removal system 70.

[0070] At the FIG. 1 In the embodiment shown, the wastewater line 73-1 leads to a separator device 80, which can be arranged outside the pre-wash zone 51 in front of the inlet tunnel 55 of the conveyor dishwasher 50.

[0071] The separator device 80 is designed to separate at least a portion of the washing liquid required to empty the dirt collection area 71-1 and discharged together with the dirt particles from the dirt collection area 71-1 from the dirt particles discharged from the dirt collection area 71-1 and to return the separated washing liquid to the water circuit of the dishwasher 50.

[0072] At the FIG. 1 In the exemplary embodiment shown of the dishwasher designed as a conveyor dishwasher 50, it is provided in detail that the washing liquid separated from the dirt particles discharged from the dirt collection area 71-1 is fed back to the washing tank 14-1 of the dishwasher 50.

[0073] The dirt discharge pump 74-1 is fluidly connected or connectable with the dirt collection area 71-1 with its suction side and fluidly connected or connectable with the separator device 80 with its pressure side.

[0074] In particular, the dirt discharge pump 74-1 can be activated independently of the introduction of fresh water into the water circuit of the dishwasher 50.

[0075] According to a conceivable implementation, the dishwasher 50 has a sensor system which is designed to detect a degree of soiling of the washing liquid, preferably in the wash tank 14-1 of the dishwasher 50, and / or to detect a soil load of the items to be treated in the dishwasher 50.

[0076] In this case, it is particularly conceivable that the dirt discharge pump 74-1 of the dirt discharge system 70 is controlled depending on the detected degree of soiling of the washing liquid and / or depending on the detected dirt load of the items to be treated in the dishwasher 50.

[0077] At the FIG. 1 In the exemplary embodiment of the dishwasher 50 according to the invention shown, it is provided that the separator device 80 has a collecting container 81 which is fluidly connected or connectable to the dirt discharge system 70 and to which the washing liquid required for emptying the dirt collection area 71-1 with the dirt particles from the dirt collection area 71-1 is supplied when the dirt collection area 71-1 is emptied.

[0078] The collecting container 81 is assigned a sieve system 82, with which at least a part of the washing liquid required for emptying the dirt collection area 71-1 and discharged together with the dirt particles from the dirt collection area 71-1 is separated from the dirt particles discharged from the dirt collection area 71-1.

[0079] In particular, the separator device 80 is assigned a waste water pump 83, which is designed to feed the washing liquid separated in the separator device 80 back into the water circuit of the dishwasher 50, preferably as needed, at predetermined times and / or events or continuously.

[0080] In FIG. 2 a second exemplary embodiment of the dishwasher 50 according to the invention is shown, which is a dishwasher 50 designed as a programmable automatic machine, which has a single treatment chamber in which washing liquid is sprayed onto the items to be treated via spray nozzles.

[0081] In the wash tank of the dishwasher 50 designed as a program machine, a dirt discharge system 70 is arranged, as previously described in principle with reference to the FIG. 1 As with the conveyor dishwasher 50 shown in FIG. 1 In the embodiment of the dishwasher 50 according to the invention shown, a separator device 80 is assigned to the automatic dirt discharge system 70.

[0082] The dirt collection system 70 is arranged within the wash tank 14 of the dishwasher 50, which is designed as a programmable automatic dishwasher. The dirt collection system 70 has a tank cover strainer 20, which is preferably arranged in the wash tank 14 above the liquid level of the wash liquid held in the wash tank 14. The tank cover strainer 20 serves to separate dirt particles from the sprayed wash liquid that flows back into the wash tank by gravity. For this reason, a suitable mesh size must be provided for the tank cover strainer 20.

[0083] The dirt collection system 70 also includes a dirt collection area 71, which is designed as a chamber that is open at the top. The dirt particles separated by the tank cover screen 20 are fed to the dirt collection area 71 via the opening of the chamber-shaped dirt collection area 71. For this purpose, the tank cover screen 20 has a drainage slope in the form of a gradient directed toward a supply opening 22, with the upwardly open dirt collection area 71 being arranged below the supply opening 22.

[0084] As in FIG. 2 As shown, it is conceivable, for example, that the tank cover screen 20 is funnel-shaped at least in some areas, wherein the supply opening 22 is formed within the funnel-shaped area 21 of the tank cover screen 20, and preferably in the tapered area of ​​the funnel-shaped area 21 of the tank cover screen 20.

[0085] Furthermore, it is preferred if the dirt collecting area 71 is funnel-shaped at the upper end in order to be able to be inserted or received into the feed opening 22 of the tank cover sieve 20.

[0086] When operating the dishwasher 50 (not in FIG. 2 In the washing zone (shown in the figure), washing liquid is sprayed, with a portion of the sprayed washing liquid flowing back into the washing tank 14 via the tank cover strainer 20. The remaining portion of the sprayed washing liquid flows by gravity directly into the dirt collection area 71 via the inlet opening 22 provided in the tank cover strainer 20. The dirt particles rinsed off the washware during the washing process—provided they are larger than the mesh size of the tank cover strainer 20—are prevented by the tank cover strainer 20 from entering the washing liquid collected in the washing tank 14. Instead, the dirt particles separated by the tank cover strainer 20 are moved through the drainage slope to the inlet opening 22 and thus reach the dirt collection area 71.

[0087] In order to be able to empty the dirt collection area 71, preferably automatically, the dirt collection system 70 preferably further comprises a dirt discharge pipe system. This dirt discharge pipe system consists in the FIG. 2 The illustrated embodiment of the dirt removal system 70 consists of a standpipe 72, which is connected to the lower region of the dirt collection area 71. The standpipe 72 is connected to the suction-side inlet of a dirt removal pump 74. The pressure-side outlet of the dirt removal pump 74 opens into a dirty water line 73, so that when the dirt removal pump 74 is activated, the contents of the dirt collection area 71 can be drained away from the washing zone.

[0088] The dirt discharge pump 74 is preferably designed to discharge the dirt particles collected in the dirt collection area 71, together with the washing liquid also collected in the dirt collection area 71, continuously or at predetermined times or events. In particular, it is conceivable that the dirt discharge pump 74 is controlled via the aforementioned controller 100 depending on the quantity of dirt particles collected in the dirt collection area 71.

[0089] According to the invention, the pumping out of dirt from the dirt collection area 71 takes place depending on the liquid level in the washing tank 14.

[0090] At the FIG. 2In the embodiment shown, the dirty water line 73 leads to a separator device 80. The separator device 80 is designed to separate at least a portion of the washing liquid required to empty the dirt collection area 71 and discharged together with the dirt particles from the dirt collection area 71 from the dirt particles discharged from the dirt collection area 71 and to return the separated washing liquid to the water circuit of the dishwasher 50.

[0091] The invention is not limited to the embodiments described in connection with the drawings.

Claims

1. A dishwasher (50) having at least one washing system (51, 52) configured as a recirculation loop, in particular a tableware or utensil washer, which is configured as a program automation or as a conveyor dishwasher, wherein the at least one washing system (51, 52) comprises a nozzle system having at least one washing nozzle (13; 13-1, 13-2) for spraying washing liquid onto the items to be cleaned, a washing tank (14; 14-1, 14-2) for collecting at least a portion of the sprayed washing liquid, and a washing pump (11; 11-1, 11-2) for feeding washing liquid collected in the washing tank (14; 14-1, 14-2) to the at least one washing nozzle (13; 13-1, 13-2), and wherein a dirt discharge system (70) associated with the at least one washing system (51, 52) is provided, wherein a tank cover screen (20-1) is associated with the dirt discharge system (70), which screen is configured so as to separate dirt particles from the sprayed washing liquid that flows back into the washing tank (14; 14-1, 14-2) due to gravity, wherein the dirt discharge system (70) comprises a dirt collection region (71) arranged at least regionally in the washing tank (14; 14-1, 14-2) for collecting the dirt particles separated from the washing liquid by means of the tank cover screen (20-1), and wherein a dirt discharge pump (74, 74-1) fluidly connected to the dirt collection region (71) is provided, via which the dirt collection region (71) can be emptied, in particular as needed, characterized in that the tank cover screen (20-1) is arranged above the dirt collection region (71) and has a drainage slope in the form of a gradient directed toward a feed opening (22), wherein the dirt collection region (71) is open at the top and arranged below the feed opening (22), so that the dirt particles separated by means of the tank cover screen (20-1) can pass through the feed opening (22) into the dirt collection region (71), wherein a separator apparatus (80) is assigned to the dirt discharge system (70), which is designed to separate at least part of the washing liquid required for emptying the dirt collection region (71) and discharged together with the dirt particles from the dirt collection region (71) from the dirt particles discharged from the dirt collection region (71) and to return the separated washing liquid to the water circulation of the dishwasher (50), wherein the suction side of the dirt discharge pump (74; 74-1) is fluidly connected or connectable to the dirt collection region (71), and wherein the pressure side of the dirt discharge pump (74, 74-1) is fluidly connected or connectable to the separator device (80), wherein the dishwasher (50) has a control device (100) which is designed to actuate the dirt discharge pump (74; 74-1) of the dirt discharge system (70) based on a liquid level in the washing tank (14; 14-1, 14-2).

2. The dishwasher (50) according to claim 1, wherein the dirt discharge system (70) with the separator apparatus (80) is configured so as to feed the washing liquid separated from the dirt particles discharged from the dirt collection region (71) back to the washing tank (14; 14-1, 14-2) of the dishwasher (50).

3. The dishwasher (50) according to claim 1 or 2, wherein the control device (100) is designed to actuate the dirt discharge pump (74; 74-1) of the dirt discharge system (70) independently of fresh water entering the water circulation of the dishwasher (50).

4. The dishwasher (50) according to any one of claims 1 to 3, wherein the dishwasher (50) comprises a sensor system, which is configured so as to detect a level of soiling of the washing liquid preferably in the at least one washing tank (14; 14-1, 14-2) of the dishwasher (50) and / or to detect a dirty loading of the items to be washed in the dishwasher (50), wherein the control device (100) is configured so as to actuate the dirt discharge pump (74; 74-1) of the dirt discharge system (70) depending on the detected level of soiling of the washing liquid and / or depending on the detected dirty loading of the items to be washed in the dishwasher (50).

5. The dishwasher (50) according to any one of claims 1 to 4, wherein the separator apparatus (80) comprises a collection container (81) that is fluidly connected or connectable to the dirt discharge system (70), to which, upon emptying of the dirt collection region (71), the washing liquid with the dirt particles, which is required in order to empty the dirt collection region (71), is fed from the dirt collection region (71), wherein a screen system (82) is associated with the collection container (81), with which screen system at least a portion of the washing liquid required for emptying the dirt collection region (71) and discharged from the dirt collection region (71) together with the dirt particles is separated from the dirt particles discharged from the dirt collection region (71).

6. The dishwasher (50) according to claim 5, wherein the separator apparatus (80) is configured so as to preferably automatically discharge from the separator apparatus (80) the dirt particles separated from the washing liquid in the separator apparatus (80).

7. The dishwasher (50) according to claim 5 or 6, wherein an overflow system is associated with the collection container (81) of the separator apparatus (80), which system fluidly connects the collection container (81) with a local drain or with the washing tank (14; 14-1, 14-2) of the dishwasher (50).

8. The dishwasher (50) according to any one of claims 1 to 7, wherein the separator apparatus (80) is associated with a waste water pump (83), which is configured, in particular as needed, so as to feed the washing liquid separated in the separator apparatus (80) back to the water circulation of the dishwasher (50) at predetermined times and / or events or continuously.

9. The dishwasher (50) according to claim 8, wherein the separator apparatus (80) is associated with a sensor system configured so as to detect the amount of washing liquid separated in the separator apparatus (80), and wherein the control device (100) is configured so as to actuate the waste water pump (83) depending on the amount of the washing liquid separated from the dirt particles in the separator apparatus (80).

10. The dishwasher (50) according to any one of claims 6 to 9 and claim 5, wherein a control device (100) is configured so as to cyclically actuate the waste water pump (83) at least as needed or at predetermined or determinable times or events, in particular such that at least partial rinsing of the screen system of the separator apparatus (80) is achievable.

11. The dishwasher (50) according to any one of claims 1 to 10, wherein the separator apparatus (80) comprises a filter system configured so as to filter the washing liquid separated from the dirt particles in the separator apparatus (80) prior to its return to the water circulation of the dishwasher (50).

12. The dishwasher (50) according to any one of claims 1 to 11, wherein the separator apparatus (80) is associated with a heat exchange system for heat recovery of the washing liquid separated from the dirt particles in the separator apparatus (80), in particular as needed or continuously.

13. The dishwasher (50) according to any one of the preceding claims, wherein the dishwasher (50) is configured as a conveyor dishwasher, wherein the at least one washing system (51, 52) is configured as at least one washing zone, and wherein, in addition to the at least one washing system configured as a washing zone (51, 52), the conveyor dishwasher comprises at least one rinsing zone as well as a conveyor device for conveying the items to be washed through the at least one washing system (51, 52) configured as a washing zone and the at least one rinsing zone that is downstream of the washing system (51, 52) when viewed in the conveying direction of the items to be washed; or wherein the dishwasher (50) is configured as a program automation and comprises a treatment chamber in which the washing system (51, 52) is configured.