Patent Application
20250017439
The invention relates generally to the field of industrial washing. Specifically, the present invention relates to dishwashers, in particular commercial dishwashers, which are configured as box-type dishwashers.
Box-type dishwashers are manually loadable and unloadable dishwashers. The box-type dishwashers (also referred to as “batch dishwashers”) can be tableware rack sliding dishwashers (“hood-type warewashers”) or front loaders (“front loader warewashers”). Front loaders can be under-counter machines, top-counter machines, or free-standing front loaders.
A dishwasher configured as a box-type dishwasher typically comprises a treatment chamber for the cleaning of washware. Typically, a washing tank is arranged below the treatment chamber, in which liquid can flow back from the treatment chamber due to gravity. In the washing tank, there is washing liquid, which is typically water, to which a cleaning agent may be added.
Furthermore, a dishwasher configured as a box-type dishwasher typically comprises a washing system having a washing pump, a conduit system connected to the washing pump, and a nozzle system having at least one washing nozzle. The washing liquid located in the washing tank can be conveyed from the washing pump via the conduit system to the washing nozzles and, through the washing nozzles, sprayed onto the washware to be cleaned in the treatment chamber. The sprayed washing liquid subsequently flows back into the washing tank.
Such a dishwasher configured as a box-type dishwasher is known, for example, from the publication DE 10 2005 023 429 A1.
In particular, the term “washware” as used herein should be understood to refer to crockery, glasses, cutlery, cooking utensils, oven utensils, and serving trays.
A commercial dishwasher configured as a box-type dishwasher differs from a domestic dishwasher in particular in that a commercial dishwasher must be designed in such a way that, depending on the cleaning program selected, cycle times of between one and five minutes can be realized, while domestic dishwashers typically have run times of up to 2.5 hours or more. Due to the short program duration required for commercial dishwashers, household dishwasher techniques are not readily transferable to commercial dishwashers.
Commercial dishwashers configured as box-type dishwashers typically operate in two main process steps: a first step involving washing with a washing liquid and a second step involving rinsing with heated fresh water and dosed rinsing aid.
In order to perform these process steps, a commercial dishwasher configured as a box-type dishwasher is typically equipped with two independent liquid systems that are completely separated from one another. The one liquid system is a washing water circuit which is responsible for washing the washware, wherein the washing is carried out with circulated water from the washing tank of the dishwasher. The other liquid system is a fresh water system, which is responsible for rinsing. The rinsing is carried out with fresh water, preferably fresh water from a boiler. After spraying, the fresh water is likewise taken into the washing tank of the dishwasher.
The primary task of rinsing is to remove any remaining lye on the washware. The rinsing water flowing in the washing tank during the rinsing step is additionally used in order to regenerate the washing water in the washing tank.
Before fresh water is sprayed as a rinsing liquid during the rinsing and thereby fed into the washing tank of the dishwasher, a quantity of washing liquid equal to the quantity of fresh water is pumped out of the washing tank.
Typically, commercial dishwashers configured as box-type dishwashers are equipped with a plurality of programs. These programs are distinguished primarily by different lengths of program run times of the washing process. The operator has the option of selecting a short washing program for lightly soiled washware or a correspondingly longer washing program for heavily soiled washware.
Commercial dishwashers configured as box-type dishwashers for batch-wise loading and unloading of the treatment chamber with washware are, in particular, front loaders or rack sliding machines. For front loaders, the washware is placed in a rack, and the rack loaded with washware is placed in the treatment chamber of the dishwasher through a front door and removed again through the front door after cleaning. In rack sliding machines, the tableware racks loaded with washware are manually pushed from an input side into the treatment chamber and, after completion of a washing program, manually removed from an output side of the treatment chamber. Front loaders and rack sliding machines contain only a single treatment chamber for treating the washware. The front loaders can be under-counter machines or table-top machines.
Commercial dishwashers that are designed as box-type dishwashers mainly use two drying methods. In the first method, the washware that is still hot after the rinsing process is removed from the machine, where it then dries in the ambient air for four to ten minutes. In the aforementioned method, in order to dry the washware, it is typically left in the racks in which it was placed for cleaning in the dishwasher.
According to the second method, which is applicable for commercial front loaders or under-counter dishwashers, air drying occurs within the treatment chamber of the dishwasher. Here, fresh air drying systems are used. Such fresh-air drying systems for commercial front loaders or under-counter dishwashers always operate at a high airflow rate in the range of 25 to 100 m3 per hour in order to allow the washware remaining in the treatment chamber to dry in a very short time. The high airflow rates are due to the brevity of the drying process in the commercial field. Compared to conventional drying of a domestic dishwasher, the active drying time of a commercial dishwasher is many times shorter. While programmed run-time drying in a domestic dishwasher is approximately 30 minutes to 2.5 hours, programmed run-time drying in commercial use is between 1.5 and 5 minutes.
During air-drying in a commercial dishwasher configured as a front loader or under-counter dishwasher, fresh air is drawn in from the outside and passed through the treatment chamber of the dishwasher in order to take up moisture from the washware to be dried. Typically, the drying air loaded with moisture is then blown out as exhaust air into the room where the dishwasher is installed.
However, for hood-type dishwashers, such air drying is not common within the treatment chamber of the dishwasher, because hood-type dishwashers are designed so that, immediately after the end of the rinsing phase, the hood is opened and the washware typically accommodated in the washing baskets is removed. The washware can then dry off in the ambient air according to the first drying method.
Particularly due to the increasing need to clean reusable plastic washware, solutions are sought in particular for integrating an active drying function into the washing process with a hood-type and/or universal dishwasher, because plastic washware demonstrates a poor self-drying effect due to the low heat capacity, and thus it is necessary to integrate an active drying step after the washing process.
The invention addresses in particular on the problem of integrating a high-performance drying function into the design space of a market-typical hood-type dishwasher, so that no additional design space outside the machine base surface is required for the drying function.
Accordingly, the invention relates in particular to a commercial dishwasher in the form of a hood-type dishwasher, in particular a hood sliding dishwasher, wherein the dishwasher has a hood that can be moved in a vertical direction between an open position and a closed position, in particular a linearly slidable hood. The hood comprises two opposing side walls and a front wall on the front side connecting the side walls. In the closed position of the hood, the side walls and the front wall of the hood at least partially or regionally bound a treatment chamber of the dishwasher. By contrast, in the open position of the hood, the side walls and the front wall of the hood lie at least partially or regionally above an upper wall and/or ceiling region, which bounds the treatment chamber upwardly and is fixedly connected to a rear wall of the treatment chamber and at least partially or regionally bounds a clearance therein.
The solution according to the invention is in particular characterized in that the dishwasher comprises a drying module, which is arranged on the horizontal wall and/or ceiling region of the dishwasher and is configured such that it is completely accommodated in the laterally bounded clearance by the side walls and front side of the hood when the hood is open.
The advantages achievable with the solution according to the invention are obvious: by providing such a drying module, a hood-type washer can also be equipped with a powerful drying function without increasing the design space of a market-typical hood-type washer, because the drying module is fully integrated in the necessary design space of a market-typical hood-type washer. In other words, despite the provision of the drying module, no additional design space outside the machine base surface is needed for the drying function.
Because the drying module is integrated in a vertical direction using the available construction space, an identical set-up surface (base surface) of the machine can be realized compared to market-typical hood-type dishwashers without a drying module.
On the other hand, the drying module guarantees a high performance of the drying, because, with the drying module, an air circulation takes place within the closed treatment chamber of the hood-type dishwasher, and thus a very high circulation rate/air flow rate can be realized without causing high losses in the installation room.
Apart from this, an increased drying temperature can be set with the solution according to the invention, because the drying air is circulated within the treatment chamber of the hood-type dishwasher.
Preferably, the drying module is configured such that an upper wall and/or ceiling region of the drying module lies in a horizontal plane, which is spaced apart from the horizontal plane by a maximum of 30 cm, preferably by a maximum of 25 cm, and even more preferably by a maximum of 20 cm, in which horizontal plane, in the open position of the hood, there lies an upper edge region of the side walls and/or the front wall of the hood.
The upper wall and/or ceiling region bounding the treatment chamber of the dishwasher according to the invention upwardly and the rear wall of the treatment chamber are in particular fixedly connected to a machine frame or a base frame of the dishwasher.
With regard to the drying module according to the invention, it is provided in particular that it comprises a housing and a suction fan, in particular in the form of a radial or axial fan, accommodated in the housing. In the housing, and preferably in the upper wall and/or ceiling region of the housing, a fresh air inlet is provided, via which fresh air can be drawn out of the installation room of the dishwasher and into the housing. In the housing, a drying air outlet is provided, which is fluidly connected to a drying air inlet of the treatment chamber, via which outlet the fresh air sucked into the housing of the drying module can be supplied to the treatment chamber by means of the suction fan. In a state of the drying module when it is mounted on the dishwasher, the drying air inlet of the treatment chamber corresponds to the drying air outlet of the drying module.
In this design variant, it is provided in particular that an effective flow cross-section of the fresh air inlet provided in the housing is preferably variably adjustable, in particular with the aid of a ventilation slider associated with the fresh air inlet.
According to realizations of the dishwasher according to the invention, the drying air inlet of the treatment chamber fluidly connected to the drying air outlet of the drying module is formed in the upper wall and/or ceiling region of the treatment chamber bounding the treatment chamber upwardly. Of course, other design variants can also be considered here.
Preferably, it is provided that the drying air outlet of the drying module or the drying air inlet of the treatment chamber fluidly connected to the drying air outlet of the drying module is associated with an air nozzle system having a plurality of adjustable air nozzles, in order to orient the drying air introduced or to be introduced into the treatment chamber accordingly with respect to the washware to be dried or treated.
According to implementations of the dishwasher according to the present invention, it comprises at least one air outlet for providing pressure compensation in the treatment chamber when drying air is introduced into the treatment chamber. In particular, the air outlet thus serves to discharge the drying air introduced into the treatment chamber. In particular, it is suggested that the at least one air outlet is preferably configured at least partially or regionally in the upper wall and/or ceiling region of the treatment chamber that upwardly bounds the treatment chamber.
According to preferred implementations, the dishwasher comprises a first air outlet for discharging a first portion of the drying air introduced into the treatment chamber, for example, into the installation room of the dishwasher, and a second air outlet for discharging a second portion of the drying air introduced into the treatment chamber. The second air outlet is preferably fluidly connected to an air inlet configured in the housing of the drying module.
In this context, it is conceivable that the dishwasher is associated with a heat exchange system, to which at least a portion of the drying air discharged via the first air outlet of the dishwasher is supplied, before the drying air is output into the installation room of the dishwasher. In this respect, the blowing of drying air into the installation room of the dishwasher cannot lead to any negative impacts on the room climate, because it is prevented that the moisture content of the air in the room (ambient air) is increased through the blowing of drying air loaded with moisture and warm drying air in comparison to the air in the room. In particular, with this measure, the risk that the moisture content of the air in the room is increased to the extent that undesirable condensation of water vapor occurs, in particular on cool interfaces in the room, can be counteracted.
Also in the last mentioned design variants of the dishwasher according to the invention, it is suggested that an effective flow cross-section of the first air outlet is preferably variably adjustable, in particular with the aid of a ventilation slider associated with the first air outlet.
Alternatively or additionally, an effective flow cross-section of the second air outlet and/or an effective flow cross-section of the air inlet of the drying module fluidly connected to the second air outlet is/are preferably variably adjustable, in particular with the aid of at least one ventilation slider.
According to implementations of the dishwasher according to the invention, it is provided that the housing of the drying module is divided into a first region and a second region. In the first region of the housing of the drying module, the fresh air inlet of the drying module opens, as does the air inlet fluidly connected to the second air outlet of the treatment chamber of the dishwasher. In the second region of the housing of the drying module, the drying air inlet of the treatment chamber opens.
In particular, it is provided that the suction side of the suction fan is fluidly connected to the first region of the housing of the drying module and the pressure side of the suction fan is fluidly connected to the second region of the housing of the drying module.
According to further developments of the last mentioned design variant of the dishwasher according to the invention, it is provided that, in the second region of the housing of the drying module, an in particular controllable or optionally switchable heating device is arranged for heating, in particular as needed, of the air supplied via the suction fan to the second region of the housing of the drying module.
In particular, the heating device comprises at least one electrically operated heating element. In addition to the heating device of the drying module, the dishwasher comprises at least one further electrically operated heating device for heating the treatment liquid to be sprayed during operation of the dishwasher, if necessary.
In this context, it is advantageous that a control device is provided, which is configured so as to control the electrical power consumption of the heating device of the drying module as a function of an electrical power consumption of the further electrically operated heating device, in order to ensure that, despite the provision of the drying module, the total connected load of the dishwasher is not increased compared to a market-typical hood-type dishwasher.
Optionally, the suction fan of the drying module can be associated with a drying device for drying at least the air supplied to the housing of the drying module via the air inlet fluidly connected to the second air outlet of the treatment chamber and/or the fresh air sucked into the housing from the installation space of the dishwasher via the fresh air inlet.
According to a further aspect of the invention, the dishwasher can comprise an air channel system, via which at least a portion of the fresh air sucked into the housing of the drying module with the aid of the suction fan can be supplied to the treatment chamber. In particular, the air is supplied either laterally or from below.
According to a further aspect of the invention, it is provided that the dishwasher comprises a washware detection device configured so as to capture the type of washware and in particular the material of the washware received in the treatment chamber of the dishwasher. The dishwasher further comprises a control device, which is configured so as to do the following as a function of the type of washware detected or as a function of the material of the washware received in the treatment chamber of the dishwasher: set a temperature of the drying air supplied from the drying module to the treatment chamber; set an amount of drying air supplied per unit of time to the treatment chamber; set a timepoint for activation of the drying module and/or a duration of activation of the drying module.
The present invention further relates to a method for operating a dishwasher, wherein the dishwasher is a dishwasher of the aforementioned type according to the invention. The method provides for the following method steps:
In the method according to the invention, it is provided in particular that, upon completion of the rinsing process, the drying module is activated in order to expose the cleaned washware to air, in particular heated drying air, within the closed treatment chamber.
Alternatively or additionally, it is conceivable that between the method step (iii) and the method step (iv), the drying module is preferably activated for up to 15 seconds in order to strike the cleaned washware with air during a so-called drip-off phase between the washing phase and the rinsing phase.
The invention further relates to a drying module configured so as to be mounted, in particular, on an upper wall and/or ceiling region of a commercial dishwasher designed as a box-type dishwasher. The commercial dishwasher in this sense can be in particular a hood-type dishwasher or a front-loader. The drying module can in particular be retrofitted onto the dishwasher.
The drying module comprises a housing and a suction fan, in particular in the form of a radial or axial fan, accommodated in the housing. In the housing, and preferably in the upper wall and/or ceiling region of the housing of the drying module, a fresh air inlet is provided, via which fresh air can be sucked into the housing. A drying air outlet is further provided in the housing, via which the fresh air sucked into the housing of the drying module can be supplied to the treatment chamber of a dishwasher by means of the suction fan. In particular, it is provided here that an effective flow cross-section of the fresh air inlet provided in the housing is preferably variably adjustable, in particular with the aid of a ventilation slider associated with the fresh air inlet.
According to further developments of the drying module according to the invention, it is provided that an air inlet is configured in the housing of the drying module, via which air can be supplied from the housing to the treatment chamber of the dishwasher. In this context, in particular, it can be appreciated that an effective flow cross-section of the air inlet of the drying module is preferably variably adjustable, in particular with the aid of at least one ventilation slider.
Preferably, the housing of the drying module is divided into a first region in which opens the fresh air inlet of the drying module and an air inlet of the drying module that can be fluidly connected to the treatment chamber of the dishwasher, and a second region in which opens the drying air inlet of the treatment chamber. The suction side of the suction fan is fluidly connected to the first region, and the pressure side of the suction fan is fluidly connected to the second region.
In the second region of the housing of the drying module, an in particular controllable or optionally switchable heating device is preferably arranged for heating, in particular as needed, of the air supplied via the suction fan to the second region of the housing of the drying module.
Alternatively or additionally, it is provided that a drying device is associated with the suction fan of the drying module for drying at least the air supplied to the housing of the drying module via the air inlet that can be brought into fluid communication with the treatment chamber of the dishwasher.
An exemplary embodiment of the dishwasher according to the invention is described in further detail below, with reference to the accompanying drawings.
The following are shown:
The exemplary embodiment of the dishwasher 1 according to the invention shown in the drawings is designed as a hood-type dishwasher, which can be loaded and unloaded with a washing basket via a hood 2. The hood 2 can be pushed upward in the vertical direction via a handle.
Such hood-type dishwashers are designed for cleaning large quantities of washware in as short a time as possible.
For example, in a hood-type dishwasher from the company HOBART, the duration of the preset standard program, which is typically used for normally soiled washware such as plates, bowls, cups, and glasses, is only about 70 seconds, i.e., the theoretical capacity is up to 52 baskets per hour.
Almost without exception, commercial-grade dishwashers 1 are equipped with rotating washing-and-rinsing systems. A washing-and-rinsing system typically consists of a washing arm and a rinsing arm. A commercial-grade dishwasher 1 of the type considered herein typically comprises an upper as well as a lower washing-and-rinsing system.
During operation, the soap water (washing liquid) is supplied from the washing tank to the washing arms via a pipe system using a pump. The washing arms are used in order to apply the soap water/washing liquid to the washware to be cleaned. The dirt is removed from the washware and integrated into the soap water. The soap water then flows back into the washing tank of the dishwasher 1 via a screen system that retains coarse dirt residues.
Further, a rinsing system is provided for conveying rinsing liquid by means of a rinsing pump through a rinse line system to rinsing nozzles, which are directed towards the region of the washware to be cleaned in the treatment chamber 5 of the dishwasher 1. The sprayed rinsing liquid falls from the treatment chamber 5 into the washing tank by gravity. The rinsing liquid line system connects the pressure side of the rinsing pump to the rinsing nozzles.
Before spraying rinsing liquid during the rinsing phase, an amount of the washing liquid corresponding to the rinsing liquid is pumped from the washing tank by means of a drain pump, whose suction side is connected via a drain line into a sump of the washing tank.
If the washing tank is empty before a first start of the hood-type dishwasher, it must first be filled with fresh water via a fresh water line or by means of the rinsing system and its rinsing pump with fresh water or another rinsing liquid or washing liquid.
The rinsing liquid can be fresh water or fresh water mixed with rinse aid.
The washing liquid contains cleaner, which is preferably automatically added to the liquid contained in the washing tank by a cleaner dosing apparatus.
As can be seen in the drawings, the hood 2 of the exemplary embodiment of the dishwasher 1 according to the invention is movable vertically between an open position and a closed position. The hood 2 comprises two opposing side walls 3 and a front wall 4 on the front side connecting the side walls 3. In the closed position of the hood 2, the side walls 3 and the front wall 4 of the hood 2 at least partially or regionally bound the treatment chamber 5 of the dishwasher 1.
In the open position of the hood 2, on the other hand, the side walls 3 and the front wall 4 of the hood 2 at least partially or regionally laterally bound a clearance. In the open position of the hood 2, the side walls 3 and the front wall 4 of the hood 2 lie at least partially or regionally above an upper wall and/or ceiling region 6, which bounds the treatment chamber 5 upwardly and is fixedly connected to a rear wall 7 of the treatment chamber 5.
In the clearance, which is laterally bounded at least partially or regionally by the side walls 3 and the front wall 4 of the hood 2 when the hood 2 is in its open position, a drying module 8 is accommodated. The drying module 8 is arranged such that, in the open position of the hood 2, it is completely accommodated in the clearance that is laterally bounded by the side walls 3 and the front wall 4 of the hood 2.
For example, as illustrated in
According to the views in
In particular, with reference to the illustrations in
In detail, the drying module 8 comprises a housing 9 and a suction fan 10 accommodated with the housing 9. The suction fan 10 is in particular a radial or axial fan.
In the housing 9, and preferably in the upper wall and/or ceiling region of the housing 9 of the drying module 8, a fresh air inlet 11 is provided, via which fresh air can be drawn out of the installation room of the dishwasher 1 and into the housing 9 of the drying module 8.
In the housing 9 of the drying module 8, a drying air outlet 12 is provided, which is fluidly connected to a drying air inlet 13 of the treatment chamber 5 of the dishwasher 1, via which outlet the fresh air sucked into the housing 9 of the drying module 8 can be supplied to the treatment chamber 5 by means of the suction fan 10.
In the embodiment of the dishwasher 1 according to the invention as shown in the drawings, the drying air inlet 13 of the treatment chamber 5 corresponds to the drying air outlet 12 of the drying module 8.
An effective flow cross-section of the fresh air inlet 11 provided in the housing 9 of the drying module 8 is preferably variably adjustable, namely with the aid of a ventilation slider associated with the fresh air inlet 11.
The drying air outlet 12 of the drying module 8 or the drying air inlet 13 of the treatment chamber 5 fluidly connected to the drying air outlet 12 of the drying module 8 is associated with an air nozzle system 14 having a plurality of adjustable air nozzles, via which the drying air introduced or to be introduced into the treatment chamber 5 can be oriented accordingly.
The dishwasher 1 comprises a first air outlet 15 for discharging at least a first portion of the drying air introduced in the treatment chamber 5 into the installation room of the dishwasher 1.
The dishwasher 1 further comprises a second air outlet 16 for discharging at least a second portion of the drying air introduced in the treatment chamber 5, wherein the second air outlet 16 is fluidly connected to an air inlet 17 configured in the housing 9 of the drying module 8.
In the embodiment shown in the drawings, the second air outlet 16 of the treatment chamber 5 of the dishwasher 1 corresponds to the air inlet 17 configured in the housing 9 of the drying module 8.
Although not shown in the drawings, it is conceivable in principle that the dishwasher 1 is associated with a heat exchange system, to which at least a portion of the drying air discharged via the first air outlet 15 of the dishwasher 1 is supplied, preferably before the drying air is output into the installation room of the dishwasher 1.
In the exemplary embodiment of the dishwasher 1 according to the invention, an effective flow cross-section of the first air outlet 15 is preferably variably adjustable, in particular with the aid of a ventilation slider 15 associated with the first air outlet.
Likewise, an effective flow region of the second air outlet 16 is also preferably variably adjustable, namely likewise with the aid of a corresponding ventilation slider.
From the sectional views according to
In the second region 20 of the housing 9 of the drying module 8, an in particular controllable or optionally switchable heating device 21 is arranged for heating, in particular as needed, of the air supplied via the suction fan 10 to the second region 20 of the housing 9 of the drying module 8.
The invention further relates to the drying module 8 per se, i.e., without a corresponding dishwasher 1, wherein the drying module 8 can also be connected to a dishwasher 1 subsequently in order to thus optimize the drying function of the dishwasher 1.
The air inlets and outlets 11, 12, 17 of the drying module 8 and the dishwasher 1, respectively, are adjustable via corresponding adjustable sliders as needed in order to adjust the following: the rate of fresh air that is newly drawn from the ambient air in the installation room during the drying process; a rate of circulation that is circulated within the machine 1 during the drying process; and/or a rate of discharge that is discharged to the environment during the drying process.
This is necessary in order to ensure a type of pressure compensation within the treatment chamber 5, because otherwise not enough fresh air can be drawn in from the environment.
This is also necessary in order to keep the relative humidity of the drying air constant, i.e., the moisture absorbed by the air during the drying process is partially discharged from the treatment chamber 5 as exhaust air in order to replace it with fresh air having a lower relative humidity and thereby accelerating the drying process.
Aspects of the invention are briefly summarized below.
The dishwasher 1 according to the invention is a single-tank (tableware) dishwasher 1 or a box-type dishwasher in the form of a hood-type or universal dishwasher for washing various washware.
In particular, it is provided that:
The invention is not limited to the embodiments shown in the drawings, but rather results when all of the features disclosed herein are considered together.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 118 436.9 | Jul 2023 | DE | national |
