Shroud-Type Dishwashing Machine With Condensation Precipitation Device

Abstract

A shroud-type dishwashing machine for commercial use has a lower frame, a dishwashing chamber and a shroud which can be opened and at least partially surrounds the dishwashing chamber. A condensation precipitation device is connected to the dishwashing chamber when the shroud is closed. This condensation precipitation device is equipped with at least one fan for sucking vapor and/or air out of the closed dishwashing chamber, and also has at least one condensation surface for condensation of vapor.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on German Patent Application No. 10 2007 004 599.0 filed 30 Jan. 2007, upon which priority is claimed, and on Provisional Application 60/907.300 filed on Mar. 28, 2007.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a shroud-type dishwashing machine with a condensation precipitation device in order to reduce water vapor emerging from the dishwashing machine. Dishwashing machines such as these are designed for commercial use and are used, for example, in large kitchens, in order to clean plates and dishes, glasses, flatware, trays or similar articles.

2. Prior Art

In addition to conveyor-belt transport and basket-transport dishwashing machines, so-called shroud-type dishwashing machines are also used in large kitchens, in particular in large kitchens in hotels, guest houses, factory canteens, hospitals, the authorities, schools or similar facilities. Dishwashing machines such as these have a lower frame and a dishwashing chamber, which is equipped with a dishwashing or spraying system (for example with one or more spraying arms) in order to clean the plates and dishes. One characteristic feature of dishwashing machines such as these is a shroud which surrounds the dishwashing chamber and, for example, can be folded up or can be moved upwards (for example by means of a rail system) in order to open the dishwashing chamber. Baskets fitted with plates and dishes to be cleaned are normally inserted into the dishwashing chamber. The shroud is then closed and the dishwashing process is carried out. After the dishwashing process, the shroud is opened and the basket or baskets is or are removed, together with the plates and dishes that have been cleaned.

However, one problem with shroud-type dishwashing machines such as these is that considerable amounts of water vapor can escape into the working environment, for example the large kitchen, when the shroud of the dishwashing machine is opened, thus increasing the temperature and the air humidity. This water vapor makes the work of the operator considerably more difficult and, for example, the operation of machines such as these is associated with considerable operator difficulties for those wearing spectacles.

In order to overcome this problem, it is normal to wait for the dishwashing chamber to cool down before unloading the dishwashing machines, in order to reduce the amount of vapor introduced into the working environment. However, in practice, this procedure is not only associated with the disadvantage of reduced throughput of plates and dishes to be cleaned, but also leads to plates and dishes that have been cleaned and dried being subjected to a greater amount of moisture resulting from the vapor precipitating on the surfaces of the plates and dishes as they cool down.

Approaches to overcome this problem are known from the field of dishwashing machines that are used underneath work surfaces, and although these are predominantly used as small appliances for domestic purposes, they are also used in some cases in large kitchens. For example, DE 10 2005 023 428 A1 discloses a commercial dishwashing machine with a dishwashing chamber for accommodating items to be cleaned, which has a fan in order to produce an air flow. The air flow is passed from an air inlet underneath the area of the items to be cleaned, for example from a gap underneath a folding door of the dishwashing machine, through the dishwashing chamber to an air outlet, with a deflector device being used. The fan then passes the air flow to an outlet.

However, these and similar solutions that have been proposed in order to reduce the problem of water-vapor formation for small appliances and appliances used under work surfaces (see, for example, WO 2006/123947 A1 and WO 2006/120062 A1 as well) cannot be transferred directly to larger appliances for commercial use, in many cases. For example, the volume of the dishwashing chamber in shroud-type dishwashing machines is designed for the use of a fan to pass the vapor out of the dishwashing chamber into the surrounding area would not reduce the effect described above on the load in the working environment, but in some circumstances could even increase it. Furthermore, the opening shroud of shroud-type dishwashing machines results in problems because it is not possible to directly use flow guidance as is proposed for front-loader dishwashing machines in DE 10 2005 023 428 A1.

OBJECT AND SUMMARY OF THE INVENTION

One object of the present invention is therefore to propose a dishwashing machine for commercial use which is in the form of a shroud-type dishwashing machine and avoids the disadvantages described above of known shroud-type dishwashing machines. One particular aim is to design the dishwashing machine such that the load in the working environment from water vapor is considerably reduced.

This object is achieved by a shroud-type dishwashing machine embodying the invention and intended primarily for commercial use. In addition to the already described lower frame, the dishwashing chamber with the dishwashing system and the shroud which at least partially surrounds the dishwashing chamber, the dishwashing machine has at least one condensation precipitation device. This condensation precipitation device is connected to the dishwashing chamber when the shroud is closed and has at least one fan for sucking vapor out of the closed dishwashing chamber. Furthermore, at least one condensation surface for condensation of vapor is provided in the condensation precipitation device.

The dishwashing machine according to the invention considerably reduces the vapor load in the working environment since, on the one hand, vapor can be sucked out when the shroud is closed but this vapor is not ejected directly into the working environment but is at least partially condensed in advance on the condensation precipitation device. Furthermore, the proposed dishwashing machine results in the plates and dishes being dried better in the dishwashing chamber, since moisture is extracted from the dishwashing chamber.

As stated above, the expression “dishwashing machine” should be understood as meaning a dishwashing machine for a multiplicity of possible objects. These objects are preferably in the form of plates and dishes, flatware, glasses, trays or similar equipment used in large kitchens.

However, alternatively or additionally, further objects can also be cleaned, for example objects from the field of hospital requirements.

The condensation precipitation device may be accommodated entirely or partially in the shroud, in particular in a cover part of the shroud. Alternatively or additionally, it may also be completely or partially integrated in a rear wall and/or be provided with a frame which connects the shroud and the lower frame. Complete or partial integration in the lower frame itself is also feasible.

In particular, the condensation precipitation device may be connected to the dishwashing chamber via at least one connection to the shroud. This has the advantage over sucking the vapor out in the bottom area of the dishwashing chamber that less moisture is sucked up and, in particular, the sucking-out process leads to an upward flow within the dishwashing chamber, which assists drying of the plates and dishes accommodated there after they have been washed. In particular, the at least one connection may be arranged in the area of the cover of the shroud, for example in a cover part. Particularly if the condensation precipitation device is not accommodated in the shroud, in particular not in a cover part of the shroud, the condensation precipitation device may be connected to the connection via a telescopic hose and/or a flexible hose, so that this connection still remains when the shroud has been opened. However, other connection devices are also feasible for the connection between the condensation precipitation device and the connection, taking account of any possible change in the distance between these two elements during opening of the shroud.

In addition to or as an alternative to the provision of the connection in the area of the cover of the shroud, the shroud may also have further flow guiding devices in order to assist upward flow of the vapor when it is being sucked out. These flow guiding devices can assist uniform flow through the dishwashing chamber in order in this way to ensure that the plates and dishes are dried more quickly and more uniformly. In particular, flow laminates and/or a perforated intermediate cover can be provided in the cover for this purpose, in order to assist the uniformity of the flow through this area.

The fan need not necessarily be arranged integrated with or in the immediate vicinity of the other components of the condensation precipitation device. A decentralized arrangement with appropriate connection of the components is also feasible. Furthermore, it has been found to be advantageous for the condensation precipitation device to be designed such that at least a portion of the flow of the air sucked in from the dishwashing chamber or of the vapor is fed back into the dishwashing chamber again after flowing through the condensation precipitation device. This refinement on the one hand has the advantage that the vapor can be sucked out of the dishwashing chamber by the fan but that, at the same time, air is introduced into the dishwashing chamber together with an air flow which is additionally sucked up (for example at normal pressure or at a slightly raised pressure). This makes it possible to assist a circulation process without any need for a second fan to introduce or force air into the dishwashing chamber for this purpose.

In many cases, shroud-type dishwashing machines are subject to the problem that a considerable ceiling height is required in order to allow the user to open the shroud. For this reason, it has been found to be advantageous to design the shroud from more than one part. In particular, the shroud may have a cover part and a shroud casing, with the cover part and the shroud casing being at least partially separated from one another during opening of the shroud. For example, the shroud casing can be folded away from the cover part or the shroud casing can be moved vertically upward, for example essentially at right angles, with the central cover part remaining at its original point. In this case, the shroud casing slides peripherally past the cover part. However, other configurations with a split shroud are also feasible.

If the cover part is in a fixed position, the condensation precipitation device can preferably be at least partially arranged in the fixed-position cover part. In this case, in particular, this avoids the problem of connection of the condensation precipitation device to the (conventionally moving) cover part which (see above) would otherwise have been solved for example by the use of a flexible hose and/or a telescopic hose. As an alternative or in addition to the accommodation of the condensation precipitation device in the fixed-position cover part, the flow guiding device and/or the connection to the condensation precipitation device can advantageously also be provided in the fixed-position cover part.

Further advantageous exemplary embodiments relate to the design of the condensation precipitation device. For example, it may have at least one chamber with at least one inlet and at least one outlet, and may furthermore have at least one condensation outflow. The condensation outflow is used to carry the condensed vapor (condensation) away and, for example, may be connected to a waste-water connection or else may be connected to one of the tanks for the dishwashing machine, for example to a dishwashing water tank. The fan for the condensation precipitation device may be connected to the inlet and/or to the outlet. Alternatively, a plurality of fans may also be provided.

It is particularly advantageous for the chamber of the condensation precipitation device to define at least one flow channel through which vapor that has been sucked up from the dishwashing chamber is passed or forced. As an alternative or in addition to the above refinement the fan can also be connected to the at least one flow channel.

The condensation precipitation device may have at least one condenser element which comprises the at least one condensation surface for condensation of vapor. This condenser element may, for example, have at least one cold plate, in which case this at least one cold plate may not be actively cooled or else, alternatively or additionally, may be sprayed with a cooling medium. Alternatively or additionally, the at least one condenser element may also comprise at least one heat exchanger through which a cooling medium flows, in particular a plate-type heat exchanger and/or a serpentine cooling-coil type heat exchanger.

The at least one condenser element may in particular be arranged such that it, in particular the at least one condensation surface, is aligned at an angle to the horizontal. This allows condensation to flow away along the condensation surface. Furthermore, alternatively or additionally, a laminate arrangement of the at least one condenser element, a meandering arrangement and/or a parallel arrangement of a plurality of condenser elements may be provided.

It has been found to be particularly advantageous for the condensation precipitation device to be designed to at least partially recover the heat contained in the vapor that is sucked out. This device allows the dishwashing machine to be operated in a particularly energy-saving manner, and this is particularly advantageous for commercial dishwashing machines.

In particular, condensation precipitation devices with at least one condenser element which can be cooled by water have been found to be advantageous for this purpose. In this case, at least one first condenser connection can be provided, and can be connected to a water supply, in particular to a fresh-water supply, and more particularly to a cold-water supply. Furthermore, at least one second condenser connection is provided, and is connected to a reservoir tank in the dishwashing machine. Particularly when using a fresh-water supply, it has been found to be advantageous for the at least one second condenser connection to be connected to a final washing water tank since this washing water tank normally has the highest purity level in the dishwashing machine.

In particular, the dishwashing machine may be designed to carry out a dishwashing program in which, in at least one program step of the dishwashing program, the condensation precipitation device is operated in order to suck vapor out of the dishwashing chamber. A control device, for example an electronic control device and/or a control device equipped with a computer, may be provided by way of example, in order to control the dishwashing program procedure. This allows the vapor to be sucked out directly after the other washing steps have been carried out, that is to say without any need for intervention by a user, or, alternatively or additionally, it is also possible to provide intermediate suction processes. However, in particular, at least one suction program step is advantageous at the end of the dishwashing program.

As described above, it is worthwhile returning the heated cooling water to a final washing water tank for heat recovery purposes when using water-cooled condensation precipitation devices. For example, a final washing program step can be provided first of all, in which the plates and dishes are finally washed using a final washing liquid (generally water to which additives, in particular rinsing agents or the like, may be added). In a subsequent suction program step, the cooling water in the condensation precipitation device can then be heated by vapor from the dishwashing chamber in order then once again to supply this amount of heat to the final washing liquid in the final washing water tank. This makes it possible to considerably reduce the amount of energy consumed for heating the final washing liquid in the final washing water tank (which is typically preheated to a temperature of about 83 to 85° C.).

The described advantageous refinement can be implemented in particular by means of two-level control in the final washing water tank, and this can be done with little control complexity. For example, the final washing program can be continued until the level in the final washing water tank has reached a lower predetermined level. The subsequent suction program step with heated cooling water being supplied from the condensation precipitation device to the final washing water tank can then, for example, be continued until the level in the final washing water tank has once again reached an upper predetermined level. However, other types of control system or additional control mechanisms may, of course, also be implemented. The cooling water may also be transferred to another tank, for example to a circulation tank or dishwashing water tank, for partial heat recovery.

Furthermore, in particular for the described heat recovery process, at least one liquid valve may be provided for controlling a supply of a cooling medium, in particular of cooling water, to the condensation precipitation device. In this case, the dishwashing machine (or controller) is advantageously designed such that the timings for operation of the liquid valve and for operation of the fan for the condensation precipitation device are synchronized. By way of example, this synchronization can be carried out by coupling the timing for opening the liquid valve (and thus the start of the supply of cooling water to the condensation precipitation device) to the starting of the fan, for example with these activities occurring at the same time or offset by a predetermined time interval. In contrast, the liquid valve advantageously is closed, and the fan switched off, with a time offset, so that the liquid supply is stopped before the fan is switched off, for example at a time when the cooling water is no longer being adequately heated in the condensation precipitation device to supply sufficient heat to the final washing water tank. In this case, the fan can then be used on its own to suck the residual vapor remaining there out of the closed dishwashing chamber.

The end of the suction program step (or the last of the suction program steps) and therefore in particular completion of the dishwashing program may, for example, be indicated to the user of the shroud-type dishwashing machine. The user is informed that the shroud can now be opened without introducing water vapor into the working environment. Automatic opening can also be provided. Furthermore, locking systems can optionally also be provided, for example in order to prevent premature opening of the shroud before the vapor has all been sucked out.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details and features of the invention will become evident from the following description of preferred exemplary embodiments, taken in conjunction with the drawings in which the exemplary embodiments are illustrated schematically and the same reference numbers in the individual figures denote identical or functionally equivalent elements, and in which:

FIG. 1 shows a shroud-type dishwashing machine with a condensation precipitation device accommodated in the rear wall;

FIG. 2 shows an alternative shroud-type dishwashing machine with a condensation precipitation device accommodated in a cover part of the shroud;

FIG. 3 shows a further alternative embodiment with a condensation precipitation device which is accommodated in an attachment to the rear wall;

FIG. 4 shows a shroud-type dishwashing machine with a shroud which can be pivoted up;

FIG. 5 shows one exemplary embodiment of a shroud-type dishwashing machine with a condensation precipitation device which is accommodated in the lower part of the dishwashing machine;

FIGS. 6A to 6C show various exemplary embodiments of a condensation precipitation device for use in a rear wall;

FIGS. 7A to 7D show various exemplary embodiments of a condensation precipitation device for use in a cover part or an attachment to the rear wall;

FIGS. 8A and 8B show two exemplary embodiments of a condenser element with liquid cooling;

FIG. 9 shows one exemplary embodiment of a condensation precipitation device with a portion of the dried air being fed back to the dishwashing chamber; and

FIG. 10 shows one exemplary embodiment of a liquid system for one preferred dishwashing machine, illustrated schematically.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a first exemplary embodiment of a dishwashing machine 110 according to the invention in the form of a shroud-type machine. The dishwashing machine 110 has a lower frame 112 in which, for example, one or more tanks are provided for dishwashing and/or final washing liquids, as well as further elements, such as heaters, connections, controllers and the like. A control panel is normally arranged on the front face of the lower frame 112 and can be used to control the dishwashing machine 110. Alternatively or additionally, the control panel can be arranged at the top on the shroud 118 (see below) and/or separately on a side switch box.

Furthermore, the dishwashing machine 110 has a rear wall 114 which, for example, can be arranged parallel to a building wall 116 during installation of the dishwashing machine 110. Further elements of the dishwashing machine 110 can be accommodated in the rear wall 114, for example elements for supplying and carrying away dishwashing liquids, parts of the control system or else mechanical elements for controlling mechanical functions of the dishwashing machine 110.

Furthermore, the dishwashing machine 110 has a shroud 118. This shroud 118 may, for example, have a cuboid, cylindrical or else any other shape and surrounds a dishwashing chamber 120. By way of example, holding apparatuses (for example in the form of depressions, rails, steps or the like) can be provided in this dishwashing chamber 120 in order to accommodate one or more baskets for items to be cleaned (not illustrated), in which the items to be cleaned can be introduced into the dishwashing machine 110. The items to be cleaned can also be introduced directly into the dishwashing chamber 120 (without using a basket for items to be cleaned). Furthermore, one or more spraying systems is or are normally provided in the dishwashing chamber 120 (see also below, FIG. 5), as well as a trough and an outflow.

By way of example, the shroud 118 may be designed such that it is closed off at the top, at the front and on the sides, while, in contrast, the shroud 118 is open toward the rear wall 114. In this case, the rear wall 114 forms a component of the shroud 118 surrounding the dishwashing chamber 120.

The shroud 118 is connected to a rail system (not illustrated in FIG. 1) for the rear wall 114. Furthermore, an opening lever 122 is provided, by means of which the shroud 118 can be moved linearly upward in order to expose the dishwashing chamber 120, for example in order to load it with items to be cleaned, or to unload items that have been cleaned from it. The rail or elevator system is in this case normally designed such that, when in the open position (shown by dashed lines in FIG. 1), the shroud 118 is held balanced by appropriate counter weights, for example accommodated in the rear wall 114, in order not to fall back to the closed position again just by virtue of its weight.

In addition, according to the exemplary embodiment in FIG. 1, the dishwashing machine 110 has a condensation precipitation device 124, however, which is arranged in the rear wall 114 in the exemplary embodiment illustrated in FIG. 1. In this case, FIG. 1 shows one exemplary embodiment of this condensation precipitation device 124. Further possible exemplary embodiments of this condensation precipitation device 124 are shown in FIGS. 6A to 6C. Other refinements are, however, also possible.

In this example, the condensation precipitation device 124 is arranged at the upper end of the rear wall 114 and has a chamber 126 with an inlet 128 and an outlet 130 arranged at the upper end. The inlet 128 is connected by a flexible hose 132 to a connection 134 to the shroud 118. Alternative embodiments are also possible, for example the use of a telescopic hose instead of the flexible hose 132, or an alternative arrangement of the connection 134, for example on a side of the shroud 118 facing the rear wall 114, in the area of the shroud cover.

Furthermore, the condensation precipitation device 124 has condenser elements 136. In this exemplary embodiment, the condenser elements 136 are in the form of passive cold plates 138 which are arranged in the form of parallel, vertical laminates in the chamber 126 and whose surfaces 140 form condensation surfaces. Highly thermally conductive materials can preferably be used for the cold plates, for example metals, preferably stainless steel, copper, aluminum or similar materials. A total area of at least 0.1 m², preferably a larger area, is preferably available. Typically, the area does not exceed a value of about 3 m².

Furthermore, the condensation precipitation device has a fan 142 which in this exemplary embodiment is arranged adjacent to the outlet 130. This fan 142 is designed to suck moist air out of the dishwashing chamber 120 via the flexible hose 132 in a suction program step, and to pass it over the condensation surfaces 140. During this process, moisture is removed from the moist air, with condensation dripping to the condensation outflow 144 which is arranged in the bottom of the chamber 126. For this purpose, by way of example, the bottom may be designed to be slightly inclined or in the form of a funnel. Condensation can then drip from the condensation outflow 144 into an outflow 146 which, for example, can be connected to a waste-water line. Alternatively, as will be described in more detail in the following text, the outflow 146 can be connected to one or more tanks for the dishwashing machine 110.

In this case, the fan 142 is designed such that the air that is sucked in is emitted toward the cover. During this process, the condenser elements 136 ensure that this air which is carried away and is emitted into the working environment is essentially free of water vapor. This reduces or avoids the load caused by water vapor in the working environment. When moist air and/or vapor is sucked out of the dishwashing chamber 120, external air is sucked into the dishwashing chamber 120 through a gap between the shroud 118 and the lower frame 112, for pressure equalization in the dishwashing chamber 120. The pressure can also be equalized by means of appropriate gaps between the rear wall 114 and the shroud 118. To this extent, the expression used above of “surrounding” the dishwashing chamber 120 by the shroud 118 should not be understood as meaning that the intention is for the dishwashing chamber 120 to be hermetically sealed, but only that the aim is essentially to prevent or slow down moisture emerging in liquid form or in the form of vapor out of the dishwashing chamber 120 into the working environment.

FIGS. 6A to 6C show alternative exemplary embodiments of the condensation precipitation device 124, which can be used for a vertical arrangement, for example in the rear wall 114 of the dishwashing machine 110. These exemplary embodiments differ from the exemplary embodiment illustrated in FIG. 1 in the arrangement and configuration of the condenser elements 136. As in FIG. 1, the exemplary embodiments in FIGS. 6A and 6C also have cold plates 138 as passive condenser elements 136, but these are arranged differently. For example, FIG. 6A shows an arrangement of these cold plates 138 in the upper area of the chamber 126, immediately in front of the fan 142, with a meandering arrangement having been chosen for the cold plates 138. This results in the air from which the moisture has been removed (indicated symbolically by the reference number 148) being deflected a number of times. The cold plates 138 may in this case, for example, be arranged at a slight angle in order to allow the condensation to flow out and to drip toward the condensation outflow 144.

In contrast to FIG. 6A, the cold plates 138 in the exemplary embodiment shown in FIG. 6C are arranged horizontally and in the form of laminates, immediately behind the inlet 128 to the chamber 126. In this case, the air 148 is therefore passed directly over the cold plates 138.

In contrast to the exemplary embodiments shown in FIGS. 6A and 6C, the condenser element 136 in the exemplary embodiment shown in FIG. 6B has an arrangement composed of (preferably water-cooled) serpentine cooling coils 150. As will be described in more detail further below, these serpentine cooling coils may be connected, for example, to a cooling water supply (for example to a cold water connection) and, on the outflow side, for example, to an outflow and/or to one or more tanks for the dishwashing machine 110. The active cooling as illustrated in FIG. 6B results in more efficient removal of moisture, even over a relatively long time period.

FIG. 2 shows an exemplary embodiment, as an alternative to FIG. 1, of a dishwashing machine 110 in the form of a shroud-type dishwashing machine. In this exemplary embodiment, the condensation precipitation device 124 is, in contrast to the embodiment shown in FIG. 1, arranged in a cover part 152 of the shroud 118 instead of in the rear wall 114. In this exemplary embodiment, the condensation precipitation device 124 is in this case arranged in the upper part of the cover part 152 or is fitted to this cover part 152. In this case, in order to allow the condensation to flow out well the condensation precipitation device 124 is preferably arranged at a slight angle to the horizontal, as shown in FIG. 2, for example at an angle of 5 to 10°. In this case, the cover part 152 can be designed such that it moves upward with the entire shroud during an upward movement of the shroud 118. Alternatively, as will be described in more detail in the following text using the example in FIG. 5, the cover part 152 can also be permanently connected to the rear wall 114 (or alternatively to a frame), in which case only a shroud casing is moved upward, rather than the entire shroud 118, when the shroud 118 is opened.

Once again, the condensation precipitation device 124 may be designed analogously to the exemplary embodiments described above. FIGS. 7A to 7D show various exemplary embodiments which are preferred for an arrangement in the cover part 152, by way of example.

For example, the arrangement shown in FIG. 7A once again illustrates a meandering arrangement, similar to the exemplary embodiment in FIG. 6A, of passive cold plates 138, that is to say cold plates 138 which are not liquid-cooled in this example, with condensation surfaces 140. These are arranged at an angle and allow the condensation to flow away to the condensation outflow 144. In addition, a connecting stub of the inlet 128 can also be equipped with a rim 154 which projects into the interior of the chamber 126 in order to prevent the condensation from flowing out into the inlet 128. Otherwise, the exemplary embodiment of the condensation precipitation device 124 shown in FIG. 7A corresponds essentially to the exemplary embodiment shown in FIG. 6A.

FIG. 7B shows an exemplary embodiment whose function and design correspond essentially to the example shown in FIG. 7A, but in which the cold plates 138 are sprayed via spraying elements 156 with a cooling liquid, for example with cold water. Together with the condensation, this cooling liquid flows out into the condensation outflow 144 and can either be supplied to a waste-water connection or, alternatively or additionally, to one or more tanks for the dishwashing machine 110, as well. Spraying a cooling liquid onto the cold plates 138 therefore represents an intermediate step between a passive embodiment of the condenser elements 136 and an active embodiment, and improves the efficiency of the precipitation of the condensation in the air 148 from which moisture is to be removed.

FIG. 7C shows a further exemplary embodiment, which likewise represents a modification of the condensation precipitation device 124 illustrated in FIG. 7A. Once again, cold plates 138 are illustrated as condenser elements 136, and are installed in the chamber 126 at an angle to the horizontal (for example at an angle between 5 and 10°). In contrast to the exemplary embodiment shown in FIGS. 7A and 7B, this exemplary embodiment has no meandering arrangement, however, and the cold plates 138 are, instead, in the form of perforated cold plates 138, each having one or more openings 158 through which the air 148 from which moisture is to be removed can flow from the inlet 128 to the outlet 130. The embodiments shown in FIGS. 7A to 7C may, of course, also be combined so that, for example, openings 158 may be provided in the cold plates 138 in the meandering arrangement show in FIGS. 7A and 7B, as well.

In contrast to the passive or semi-passive embodiments shown in FIGS. 7A to 7C, active cooling is provided in FIG. 7D. In this case, the condensation precipitation device 124 initially once again has a chamber 126, for example at an angle to the horizontal, in the same way as in FIGS. 7A to 7C as well, with an inlet 128, an outlet 130, a condensation outflow 144 and condenser elements 136. However, analogously to the exemplary embodiment in FIG. 6B, no passive cooling is provided for the condenser element 136, but cooling by means of serpentine cooling coils 150. In this case, there are various possible ways to design the condenser element 136, as illustrated by way of example in FIGS. 8A and 8B.

For example, in the exemplary embodiment shown in FIG. 8A, the condenser element 136 is simply in the form of a serpentine cooling coil 150, with a first condenser connection 160 for supplying cooling liquid and a second condenser connection 162 for the cooling liquid to flow away. The serpentine cooling coil 150 therefore forms a heat exchanger 164 in which an amount of heat is transferred from the air 148 from which moisture is to be removed to the cooling liquid, in the heat exchanger 164.

In contrast, in the exemplary embodiment shown in FIG. 5B, the heat exchanger 164 of the condenser element 136 is in the form of a plate-type heat exchanger 166, with flat condensation surfaces 140. Once again, serpentine cooling coils 150 may be provided in the interior of the plate-type heat exchanger 166 and, for example, be once again passed in a meandering shape through the heat exchanger 166, or else the cooling medium can flow completely and homogenously through the plates.

Other refinements of heat exchangers, as an alternative to the embodiments of the condenser elements 136 illustrated in FIGS. 6B, 7D and 8B, are also possible. In addition, combinations of the illustrated heat exchangers with other types of condenser elements 136, for example with passive cold plates 138 are feasible.

FIG. 3 shows a third exemplar embodiment of the dishwashing machine 110, which represents a modification of the exemplary embodiment shown in FIG. 1. Once again, the condensation precipitation device 124 is accommodated in the rear wall 114, but is not, as in FIG. 1, arranged parallel to the wall 116 but forms an attachment 168 to the rear wall 114, extending away essentially at right angles to the wall 116. In this case, the condensation precipitation device 124 may once again be designed, by way of example, as shown in one of the exemplary embodiments in 7A to 7D.

FIG. 4 shows an alternative exemplary embodiment of a dishwashing machine 110 in which the dishwashing machine 110 is once again in the form of a shroud-type dishwashing machine. In contrast to the exemplary embodiments in FIGS. 1 to 3, the shroud 118 is, however, in this case not moved linearly upward along the rear wall 114 but is pivoted upward on a hinge 172 for opening in a pivoting movement 170. This exemplary embodiment shows that other types of shroud-type dishwashing machines are also possible, which likewise in turn have a shroud 118, but in which the shroud 118 is opened in a modified form in comparison to the above exemplary embodiments.

Once again, a condensation precipitation device 124 is also provided in the exemplary embodiment of the dishwashing machine 110 illustrated in FIG. 4. In this case, in this exemplary embodiment, the condensation precipitation device 124 is provided in the cover part of the shroud 118. Once again, the condensation precipitation device 124 may be designed, for example, in a corresponding manner to the exemplary embodiments shown in FIGS. 7A to 7D. Alternatively or additionally, the condensation precipitation device 124 may, however, once again also be arranged in the rear wall 114 and/or in the lower frame 112. In this case, the embodiments in FIGS. 1 and 5 (see below), respectively, must be modified appropriately.

FIG. 5 shows a further exemplary embodiment according to the invention of the dishwashing machine 110. Once again, and analogously to FIGS. 1 to 3, this is a dishwashing machine 110 in which the shroud 118 is moved upwards by a linear movement along the rear wall 114. In comparison to these exemplary embodiments, however, a plurality of modifications have been carried out in this exemplary embodiment, as show in FIG. 5.

A first modification is that the condensation precipitation device 124 is accommodated in the lower frame 112. The condensation precipitation device 124 is in this case illustrated only symbolically in FIG. 5. By way of example, it may be designed as shown in the examples in FIGS. 7A to 7D. In this case, however, the inlet 128 and outlet 130 are arranged at the side, on the side of the housing 126 facing the rear wall 114, in this symbolic illustration of the condensation precipitation device 124. By way of example, dried air can be emitted to the working area through slots provided at the side on the rear wall 114.

A further modification from the exemplary embodiments mentioned above is that the shroud 118 in the exemplary embodiment of the dishwashing machine 110 as illustrated in FIG. 5 is formed from more than one part. For example, the shroud 118 has a cover part 152 which is firmly connected to the rear wall 114 and is not involved in the linear opening movement during opening of the shroud 118. In addition, the shroud 118 has a shroud casing 174 which, when the shroud 118 is in the closed state, rests at its upper end on a fold 176 on the cover part 152, and which is connected to the rail system accommodated in the rear wall 114. During opening of the shroud 118 by means of the opening lever 122, only the shroud casing 174 is therefore moved linearly upwards along the rear wall 114. This split configuration of the shroud 118 has the advantage that it is possible to reduce the space that needs to be provided to open the shroud 118 upwards, that is to say above the dishwashing machine 110. Alternatively, this allows further opening of the dishwashing machine 110 with the same space available above the dishwashing machine 110.

A dishwashing trough 178 is accommodated in the area of the lower frame 112 in the dishwashing chamber 120 of the dishwashing machine 110. Furthermore, a spraying system 180 with a plurality of (in this example) spraying arms 182, 184 which are mounted such that they can rotate is accommodated in the dishwashing chamber 120, with lower spraying arms 184 being connected to the lower frame 112, and with upper spraying arms 182 being connected to the cover part 152. By way of example, different spraying arms 182, 184 can be provided for spraying with dishwashing liquid in the circulation mode and spraying of the plates and dishes with final washing liquid.

This refinement of the spraying system 180 is not described in the above exemplary embodiments, but can be added as a worthwhile addition.

Furthermore, a flow guiding device 186 is provided in the area of the cover part 152 in the exemplary embodiment shown in FIG. 5. This flow guiding device 186 in this exemplary embodiment is in the form of a perforated plate above the spraying arms 182 and its purpose is to ensure more uniform guidance through the dishwashing chamber 120 of the air which has been sucked out in the suction program step and from which moisture is to be removed. In particular, this allows the sucked-out air 148 to flow as uniformly as possible, upwards, along the plates and dishes that have been introduced into the dishwashing chamber 120. This makes it possible to improve the drying effect. In addition to the single perforated plate illustrated here, other elements of the flow guiding device 186 can also be provided, for example corresponding laminates or the like. Furthermore. FIG. 5 also shows the inlet flow of air 148 for pressure equalization in the dishwashing chamber 120, which can be supplied, for example, through an air gap between the lower frame 112 and the shroud casing 174, or else via the rear wall 114 into the dishwashing chamber 120. Pressure-equalizing openings can also be provided, additionally or alternatively.

Once again, the cover part 152 has a connection 134. This connection 134 is connected via a hose 188 or a tube to the inlet 128 of the condensation precipitation device 124. Since, in this case, the connection 134 is arranged adjacent to the fixed-position cover part 152, the hose 188 need no longer necessarily be flexible or telescopic, as shown by way of example in FIG. 1, but may, for example, also be in the form of a fixed pipeline. This makes it possible to largely prevent mechanical damage or susceptibility to defects which could occur, for example, by a flexible hose being trapped.

FIGS. 1, 5, 6A to 6C and 7A to 7D show exemplary embodiments of condensation precipitation devices 124 in which a single fan 142 is provided in the area of the outlet 130. However, this fan 142 can also be designed in an alternative form and, for example, can be connected to the chamber 126 of the condensation precipitation device 124 via one or more tubes, rather than being connected to it directly. In this case, the fan 142 should be designed and configured so as to produce the greatest possible flow of air 148 through the condensation precipitation device 124 from the dishwashing chamber 120, with the amount of air in each case being intended to be matched to the capability to separate condensation on the condenser elements 136.

Theoretically, a fan 142 could also be connected directly to the dishwashing chamber 120 in order to force air 148 from the dishwashing chamber 120 into the condensation precipitation device 124. However, this configuration would have the disadvantage that, in this case, moist air would be forced into the working area through the pressure equalizing gaps described above (for example between the shroud 118 and the lower frame 112 or between the shroud 118 and the rear wall 114) so that, in this case, water vapor would emerge into the working area in this area before reaching the condensation precipitation device 124. For this reason, a “sucking” arrangement of the fan 142 is preferred, as described in the exemplary embodiment explained above.

In this case, however, the fan 142 can also be connected to the inlet 128 of the condensation precipitation device 126, or can be arranged in the flow channel (for example in the meandering configuration shown in FIG. 7A) between the cold plates 138. A plurality of fans 142 can also be provided in order to increase the suction performance, although this increases the design complexity and the operating costs. In order to overcome this disadvantage, FIG. 9 illustrates an exemplary embodiment of a condensation precipitation device 124 which both sucks air in from the dishwashing chamber 120 and passes it over condenser elements 136. The configuration of these condenser elements 136 corresponds essentially to that illustrated in FIG. 1. However, in addition to the use of cold plates 138, other designs are also feasible, for example the designs described above with heat exchangers 164 which are actively cooled by a cooling medium.

However, the flow channel is split immediately adjacent to the fan 142 that is incorporated in the flow channel (with the motor 190 for the fan 142 in this case being arranged outside the housing of the chamber 126). While a portion of the air 148 escapes via the outlet 130 into the working environment, a portion of the flow is once again passed back into the dishwashing chamber 142 via a return line 192, where it assists the pressure equalization, in order then to be supplied once again via the suction process into the inlet 128 of the condensation precipitation device 124. This means that at least a portion of the flow of the air 148 passes repeatedly over the condenser elements 136. In addition to assisting the pressure equalization, this design therefore results in a further reduction in the water vapor that escapes into the working environment. The ratio between the proportion of the flow which is returned and the proportion of the flow which is ejected may, for example, be determined by the opening cross sections of the outlet 130 and of the return line 192, and can be adjusted, for example via a slide valve and/or valves, in order to achieve optimum drying.

FIG. 10 shows, symbolically, one preferred refinement of the dishwashing system in the dishwashing machine 110, including the condensation precipitation device 124. In this case, in this exemplary embodiment, a heat exchanger 164 is provided in the condensation precipitation device 124 and is illustrated symbolically here in the form of a serpentine cooling coil 150. Air 148 is passed through the inlet 128 by means of the fan 142 from the dishwashing chamber 120 (not illustrated) via the heat exchanger 164 in order finally to be ejected into the surrounding area through the outlet 130.

By way of example, the heat exchanger may be designed according to one of the exemplary embodiments in FIG. 8A or 8B. Alternatively, however, it is also feasible to use a condensation precipitation device 124 as shown in the example in FIG. 7B. In this case, a first condenser connection 160 of the heat exchanger 164 is connected to a cold water connection 194. The second condenser connection 162 is in contrast preferably connected via a free outflow 196 to a final washing water tank 198 for the dishwashing machine 110. The supply of fresh water via the cold water connection 194 into the heat exchanger 164 can be controlled by a liquid valve 200, for example a solenoid valve.

The final washing water tank 198 in this exemplary embodiment is preferably in the form of a two-level tank, having an upper level sensor 202 and a lower level sensor 204. The final washing water tank is connected to the spraying system 180 via a pump 206 and pipeline system 208.

Furthermore, the dishwashing machine 110 may have a controller 210 which, for example, may be designed as described above, that is to say it may comprise in particular one or more computers, whose programming is preferably designed to carry out a dishwashing program. For example (not illustrated in FIG. 10), the controller 210 can check information from the level sensors 202, 204, can operate the pump 206, and can operate the liquid valve 200 and the motor 190 of the fan 142.

Thus, as already described above, a final washing program step, for example, may be carried out first of all, in which (for example following one or more dishwashing steps in which the dishwashing machine 110 is operated in the circulation mode), the plates and dishes in the dishwashing chamber 120 are finally washed with final washing liquid from the final washing water tank 198. By way of example, in this case, the level of the final washing liquid in the final washing water tank 198 may during this process fall from the level of the upper level sensor 202 to the level of the lower level sensor 204. When this lower level is reached, the controller 210 automatically stops the pump 206. The liquid valve 200 is preferably closed during this final washing program step.

The fan 142 can then be started in a suction program step (at the same time or preferably with a slight time offset) and the liquid valve 200 can be opened. During this process, cooling water flows through the heat exchanger 164, and condensation can precipitate on the heat exchanger 164. Air which has been sucked in from the dishwashing chamber 120 thus has moisture removed from it before it escapes into the surrounding area again. “Consumed” cooling water, which has absorbed heat from the vapor from the dishwashing chamber 120 after flowing through the heat exchanger 164, is supplied via the free outflow 196 to the final washing water tank 198 until the upper level, as defined by the upper level sensor 202, is reached again. The liquid valve 200 is then closed. The fan 142 can be switched off, thus ending the suction program step, at the same time that the liquid valve 200 is closed, or this can preferably be done after a certain lag time, during which air 148 is still sucked in from the dishwashing chamber 120.

The foregoing relates to the preferred exemplary embodiment of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.

Claims

1. A dishwashing machine for commercial use, the dishwasher comprising a lower frame, a dishwashing chamber, a shroud at least partially surrounding the dishwashing chamber, which shroud can be opened, at least one condensation precipitation device connected to the dishwashing chamber when the shroud is closed, the condensation precipitation device having at least one fan for sucking vapor and/or air out of the closed dishwashing chamber, and at least one condensation surface for condensation of vapor.

2. The dishwashing machine as claimed in claim 1, wherein the condensation precipitation device is accommodated entirely or partially in a cover part of the shroud.

3. The dishwashing machine as claimed in claim 1, wherein the condensation precipitation device is accommodated entirely or partially in a rear wall and/or in a frame which connects the lower frame and the shroud.

4. The dishwashing machine as claimed in claim 1, wherein the condensation precipitation device is accommodated entirely or partially in the lower frame.

5. The dishwashing machine as claimed in claim 1, wherein the connection of the condensation precipitation device has at least one connection to the shroud.

6. The dishwashing machine as claimed in claim 5, wherein the connection is arranged in the area of the cover of the shroud.

7. The dishwashing machine as claimed in claim 5, wherein the connection and the condensation precipitation device are connected to one another by a telescopic hose or a flexible hose.

8. The dishwashing machine as claimed in claim 5, wherein the shroud comprises at least one flow guiding device which is designed to promote a uniform flow through the dishwashing chamber, with the flow guiding device having flow laminates and/or a perforated intermediate cover.

9. The dishwashing machine as claimed in claim 1, wherein the condensation precipitation device is designed such that at least a portion of the flow of the air sucked in from the dishwashing chamber is fed back into the dishwashing chamber again after flowing through the condensation precipitation device.

10. The dishwashing machine as claimed in claim 1, wherein the shroud comprises a cover part and a shroud casing, with the shroud being designed such that the cover part and the shroud casing are at least partially separated from one another upon opening of the shroud, with the cover part preferably remaining essentially in a fixed position.

11. The dishwashing machine as claimed in claim 10, wherein the condensation precipitation device is at least partially arranged in the fixed-position cover part.

12. The dishwashing machine as claimed in claim 1, wherein the condensation precipitation device comprises at least one chamber with at least one inlet and at least one outlet, and at least one condensation outflow.

13. The dishwashing machine as claimed in claim 12, wherein the fan is connected to the inlet and/or to the outlet.

14. The dishwashing machine as claimed in claim 12, wherein the chamber defines at least one flow channel.

15. The dishwashing machine as claimed in claim 14, wherein the fan is connected to the flow channel.

16. The dishwashing machine as claimed in claim 1, wherein the condensation precipitation device comprises at least one of the following condenser elements:

at least one cold plate;

at least one cold plate which is sprayed with a cooling medium;

at least one heat exchanger through which a cooling medium flows, in particular a plate-type heat exchanger and/or a serpentine cooling-coil type heat exchanger.

17. The dishwashing machine as claimed in claim 16, wherein the at least one condenser element has at least one of the following arrangements:

the at least one condenser element is aligned at an angle to the horizontal;

the at least one condenser element has a laminate arrangement;

the at least one condenser element has a meandering arrangement;

the at least one condenser element has a parallel arrangement of at least two condenser elements.

18. The dishwashing machine as claimed in claim 17, wherein the condensation precipitation device comprises at least one condenser element which can be cooled by water, in which case at least one first condenser connection of the condenser element is connected to a fresh water supply and with at least one second condenser connection of the condenser element being connected to a reservoir tank in the dishwashing machine.

19. The dishwashing machine as claimed in claim 18, further comprising control means controlling operation of the dishwashing machine to carry out a dishwashing program including at least one program step in which the condensation precipitation device sucks vapor and/or air out of the dishwashing chamber.

20. The dishwashing machine as claimed in claim 19, wherein the control means comprises means for performing at least one at sucking-out program step out at the end of the dishwashing program.

21. The dishwashing machine as claimed in claim 19, further comprising a final washing water tank, and wherein plates and dishes which are accommodated in the dishwashing chamber are finally washed using a final washing liquid from the final washing water tank in at least one final washing program step, and means connecting the condensation precipitation device to the final washing water tank whereby cooling water heated in a subsequent sucking-out program step in the condensation precipitation device by vapor and/or air from the dishwashing chamber is passed into the final washing water tank.

22. The dishwashing machine as claimed in claim 21, wherein the final washing water tank comprises a two-level control, and wherein the control means is operable to carry out the final washing program step until the level in the final washing water tank has reached a lower level, and with the subsequent sucking-out program step being carried out until the level in the final-washing water tank has reached an upper level.

23. The dishwashing machine as claimed in claim 1 further comprising at least one liquid valve for controlling a supply of a cooling medium, and wherein the control means is operable to synchronize the timing for operation of the liquid valve and for operation of the fan.

24. The dishwashing machine as claimed in claim 23, wherein the liquid valve can be opened and the fan can be started essentially at the same time.