U.S. patent application number 12/022718 was filed with the patent office on 2008-09-04 for shroud-type dishwashing machine with condensation precipitation device.
Invention is credited to Karl Hildenbrand.
Application Number | 20080210279 12/022718 |
Document ID | / |
Family ID | 39563943 |
Filed Date | 2008-09-04 |
United States Patent
Application |
20080210279 |
Kind Code |
A1 |
Hildenbrand; Karl |
September 4, 2008 |
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.
Inventors: |
Hildenbrand; Karl;
(Oberkirch, DE) |
Correspondence
Address: |
RONALD E. GREIGG;GREIGG & GREIGG P.L.L.C.
1423 POWHATAN STREET, UNIT ONE
ALEXANDRIA
VA
22314
US
|
Family ID: |
39563943 |
Appl. No.: |
12/022718 |
Filed: |
January 30, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60907300 |
Mar 28, 2007 |
|
|
|
Current U.S.
Class: |
134/56D ;
134/105; 134/201 |
Current CPC
Class: |
A47L 15/483 20130101;
A47L 15/0081 20130101; A47L 15/488 20130101 |
Class at
Publication: |
134/56.D ;
134/201; 134/105 |
International
Class: |
A47L 15/46 20060101
A47L015/46; A47L 15/00 20060101 A47L015/00; A47L 15/42 20060101
A47L015/42 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 30, 2007 |
DE |
10 2007 004 599.0 |
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.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] 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
[0002] 1. Field of the Invention
[0003] 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.
[0004] 2. Prior Art
[0005] 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.
[0006] 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.
[0007] 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.
[0008] 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.
[0009] 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
[0010] 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.
[0011] 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.
[0012] 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.
[0013] 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.
[0014] However, alternatively or additionally, further objects can
also be cleaned, for example objects from the field of hospital
requirements.
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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.
[0023] 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.
[0024] 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.
[0025] 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.
[0026] 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.
[0027] 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.
[0028] 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.degree. C.).
[0029] 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.
[0030] 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.
[0031] 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
[0032] 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:
[0033] FIG. 1 shows a shroud-type dishwashing machine with a
condensation precipitation device accommodated in the rear
wall;
[0034] FIG. 2 shows an alternative shroud-type dishwashing machine
with a condensation precipitation device accommodated in a cover
part of the shroud;
[0035] FIG. 3 shows a further alternative embodiment with a
condensation precipitation device which is accommodated in an
attachment to the rear wall;
[0036] FIG. 4 shows a shroud-type dishwashing machine with a shroud
which can be pivoted up;
[0037] 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;
[0038] FIGS. 6A to 6C show various exemplary embodiments of a
condensation precipitation device for use in a rear wall;
[0039] 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;
[0040] FIGS. 8A and 8B show two exemplary embodiments of a
condenser element with liquid cooling;
[0041] 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
[0042] FIG. 10 shows one exemplary embodiment of a liquid system
for one preferred dishwashing machine, illustrated
schematically.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0043] 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.
[0044] 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.
[0045] 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.
[0046] 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.
[0047] 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.
[0048] 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.
[0049] 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.
[0050] 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
m.sup.2, preferably a larger area, is preferably available.
Typically, the area does not exceed a value of about 3 m.sup.2.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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.
[0055] 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.
[0056] 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.degree.. 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.
[0057] 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.
[0058] 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.
[0059] 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.
[0060] 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.degree.). 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.
[0061] 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.
[0062] 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.
[0063] 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.
[0064] 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.
[0065] 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.
[0066] 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.
[0067] 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.
[0068] 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.
[0069] 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.
[0070] 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.
[0071] 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.
[0072] This refinement of the spraying system 180 is not described
in the above exemplary embodiments, but can be added as a
worthwhile addition.
[0073] 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.
[0074] 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.
[0075] 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.
[0076] 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.
[0077] 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.
[0078] 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.
[0079] 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.
[0080] 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.
[0081] 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.
[0082] 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.
[0083] 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.
[0084] 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.
[0085] 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.
* * * * *