U.S. patent application number 12/243184 was filed with the patent office on 2009-04-30 for method for the wet treatment of laundry.
Invention is credited to Wilhelm Bringewatt, Engelbert Heinz.
Application Number | 20090106914 12/243184 |
Document ID | / |
Family ID | 40210551 |
Filed Date | 2009-04-30 |
United States Patent
Application |
20090106914 |
Kind Code |
A1 |
Bringewatt; Wilhelm ; et
al. |
April 30, 2009 |
METHOD FOR THE WET TREATMENT OF LAUNDRY
Abstract
In tunnel-type washing machines (10) for commercial laundries,
the main-wash liquid is heated by steam in particular. This means a
steam-generating system is required in the laundry. The invention
makes provision for the main-wash liquid to be heated up by means
of a flow heater, preferably a heating device (26) which has a gas
burner (28). As a result, the tunnel-type washing machine (10) can
also be used in laundries which do not have a steam generating
system. The invention also makes provision for the gas burner (28)
of the flow heater to be operated continuously since treatment
liquid which is required for other purposes, preferably treatment
liquid which is temporarily stored in a storage tank (31), is
heated up after the main-wash liquid is heated up. Uninterrupted,
economical operation of the gas burner (28) is ensured as a
result.
Inventors: |
Bringewatt; Wilhelm; (Porta
Westfalica, DE) ; Heinz; Engelbert; (Vlotho,
DE) |
Correspondence
Address: |
SMITH, GAMBRELL & RUSSELL
SUITE 3100, PROMENADE II, 1230 PEACHTREE STREET, N.E.
ATLANTA
GA
30309-3592
US
|
Family ID: |
40210551 |
Appl. No.: |
12/243184 |
Filed: |
October 1, 2008 |
Current U.S.
Class: |
8/159 |
Current CPC
Class: |
D06F 33/00 20130101;
D06F 2204/088 20130101; D06F 31/00 20130101; D06F 39/088
20130101 |
Class at
Publication: |
8/159 |
International
Class: |
D06F 35/00 20060101
D06F035/00; D06F 39/04 20060101 D06F039/04; D06F 39/08 20060101
D06F039/08 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 24, 2007 |
DE |
102007051083.9 |
Claims
1. A method for the wet-treatment of laundry, the laundry being at
least washed in a drum (12, 41, 66) which can be driven in rotation
using a heated-up treatment liquid, wherein the treatment liquid is
heated up by at least one heating device (26, 50, 67).
2. The method according to claim 1, wherein the heating device (26,
50, 67) is operated with fossil fuels.
3. The method according to claim 1, wherein the heating device (26,
50, 67) operates in the manner of a flow heater.
4. The method according claim 1, wherein the treatment liquid that
is warmed by the heating device (26, 50, 67) is pumped so as to
circulate through at least one chamber (13, 42) in the drum (12,
41, 66), which can be driven in rotation.
5. The method according to claim 1, wherein the treatment liquid
that is warmed by the heating device (26, 50, 67) is pumped in a
continuous circuit through at least one chamber (13, 42).
6. The method according to claim 1, wherein the treatment liquid
that is warmed by the heating device (26, 50, 67) is pumped so as
to circulate through at least one chamber (13, 42) that has an
outer drum (23, 24, 48).
7. The method according to claim 1, wherein the heating device (26,
50, 67) is operated continuously.
8. The method according to claim 1, wherein at least one burner of
the respective heating device (26, 50, 67) is operated in an
uninterrupted manner.
9. The method according to claim 1, wherein operation of the
heating device (26, 50, 67) is at least temporarily continued after
the treatment liquid for washing the laundry is heated up.
10. The method according to claim 1, wherein operation of the
heating device (26, 50, 67) is at least temporarily continued in
order to heat up the treatment liquid for washing the next batch of
laundry after the treatment liquid for washing the laundry is
heated up.
11. A method for the wet-treatment of laundry, the laundry being at
least washed in a drum (12, 41, 66) that can be driven in rotation
using a warmed treatment liquid, wherein treatment liquid for the
laundry in the drum (12, 41, 66) or for other purposes is heated up
or warmed alternately by a heating device (26, 50, 67).
12. The method according to claim 11, wherein temporarily stored
treatment liquid is warmed up between successive phases of
heating-up of the treatment liquid of successive batches of laundry
in the drum (12, 41, 66).
13. The method according to claim 11, wherein treatment liquid for
washing the laundry in the drum (12, 41, 66) is first heated by the
heating device (26, 50, 67) and, when this treatment liquid has
reached an intended temperature, temporarily stored treatment
liquid is warmed in at least one storage tank (31, 55, 74).
14. The method according to claim 11, wherein treatment liquid
which serves for main washing of the laundry is heated by the
heating device (26, 50, 67).
15. The method according to claim 11, wherein main-wash liquid
which serves for main washing of the laundry is heated by the
heating device (26, 50, 67).
16. The method according to claim 13, wherein the warmed treatment
liquid in the storage tank (31, 55, 74) is used to wash the laundry
into the drum (12, 41, 66).
17. The method according to claim 13, wherein the warmed treatment
liquid in the storage tank (31, 55, 74) is used to prepare
pre-heated main-wash liquid.
18. The method according to claim 1, wherein temporarily stored
treatment liquid is warmed up between successive phases of
heating-up of the treatment liquid of successive batches of laundry
in the drum (12, 41, 66).
19. The method according to claim 1, wherein treatment liquid for
washing the laundry in the drum (12, 41, 66) is first heated by the
heating device (26, 50, 67) and, when this treatment liquid has
reached an intended temperature, temporarily stored treatment
liquid is warmed in at least one storage tank (31, 55, 74).
20. The method according to claim 1, wherein treatment liquid which
serves for main washing of the laundry is heated by the heating
device (26, 50, 67).
21. The method according to claim 1, wherein main-wash liquid which
serves for main washing of the laundry is heated by the heating
device (26, 50, 67).
22. The method according to claim 19, wherein the warmed treatment
liquid in the storage tank (31, 55, 74) is used to wash the laundry
into the drum (12, 41, 66).
23. The method according to claim 19, wherein the warmed treatment
liquid in the storage tank (31, 55, 74) is used to prepare
pre-heated main-wash liquid.
Description
STATEMENT OF RELATED APPLICATIONS
[0001] This patent applications is based on and claims the benefit
under 35 USC 119 of German Patent Application No. 10 2007 051 083.9
having a filing date of 24 Oct. 2007, which is incorporated herein
in its entirety by this reference.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The invention relates to a method for the wet-treatment of
laundry, the laundry being at least washed in a drum which can be
driven in rotation using a heated-up treatment liquid, and a method
for the wet-treatment of laundry, the laundry being at least washed
in a drum which can be driven in rotation using a warmed treatment
liquid.
[0004] 2. Related Art
[0005] Various washing machines are used in commercial laundries
for the wet-treatment of laundry of any type. In this case, the
washing machines are firstly tunnel-type washing machines with a
plurality of successive chambers in a single drum which can be
driven in rotation. In the tunnel-type washing machine, the laundry
is at least washed by a pre-wash operation and a main-wash
operation. However, the tunnel-type washing machine can also serve
to wash and rinse and possibly also post-treat, for example finish,
the laundry. Secondly, so-called spin dryers are used in commercial
laundries, in which spin dryers the laundry is washed, rinsed and
spun-dry in a drum which can be driven in rotation and has only one
chamber.
[0006] Washing is performed with a treatment liquid which is heated
up at least for main-wash purposes, the laundry to be washed also
being heated to the temperature of the treatment liquid. In known
washing machines, the treatment liquid is heated using steam. This
means a steam-generating device is required in the laundry, and
this entails high investment costs.
BRIEF SUMMARY OF THE INVENTION
[0007] The invention is then based on the object of providing
methods for the wet-treatment of laundry, which methods permit the
treatment liquid to be heated up using simple means and permit
economical operation.
[0008] A method for achieving this object is a method for the
wet-treatment of laundry, the laundry being at least washed in a
drum which can be driven in rotation using a heated-up treatment
liquid, characterized in that the treatment liquid is heated up by
at least one heating device. According to the said method,
provision is made for the treatment liquid to be warmed by at least
one heating device. As a result, steam is no longer required to
heat the treatment liquid. On account of the method according to
the invention, complicated steam generation in the laundry can be
dispensed with.
[0009] The heating device is preferably a heating device which is
operated with fossil fuels, such as gas or oil in particular. A
heating device of this type requires only a gas and/or oil burner
which continuously warms the treatment liquid which is conducted
through heating coils in the burner in accordance with the
heat-exchanger principle. A heating device of this type is very
simple. Above all, a heating device of this type can be used as an
alternative or in addition to parallel operation for other
purposes. In one preferred refinement of the method, the heating
device is a flow heater which continuously warms treatment liquid
which is pumped in circulation continually through the heating
device. The treatment liquid warmed by the heating device can then
be circulated through the washing machine. This is performed by
continual pumping of the treatment liquid which is warmed by the
heating device and is cooled down as the laundry is warmed up as
the said treatment liquid is conducted through the washing machine.
In particular, treatment liquid which is warmed by the heating
device is pumped in circulation through at least one chamber of the
tunnel-type washing machine. Circulation of this type can be
realized in a simple manner and leads to continuous raising of the
temperature of the treatment liquid and the laundry through which
the treatment liquid is pumped in circulation.
[0010] In a further preferred refinement of the method, provision
is made to operate the heating device continuously, that is to say
in a substantially uninterrupted manner. In this case, the required
heating energy is controlled by the quantity of gas or oil supplied
to the heating device per unit time. However, the heating device is
operated substantially continuously, specifically fired by oil or
gas. The heating device is switched off only in the event of
relatively long unpredicted interruptions in operation or in the
event of a relatively long-lasting interruption in the washing
process.
[0011] The invention also proposes using energy which is required
for constant operation of the heating device, but is not currently
required to heat up the treatment liquid for washing the laundry in
the drum, for other purposes. The heating device can then continue
to be operated even though treatment liquid for washing the laundry
does not currently have to be heated up. In this way, operation of
the heating device is maintained even if treatment liquid for
washing the laundry temporarily does not have to be heated up. The
energy which is then further generated by the heating device is
preferably used for other purposes or to warm or heat up treatment
liquid which will be required later.
[0012] A further method for achieving the object cited in the
introduction, this method possibly also being a preferred
development of the method described above, is a method for the
wet-treatment of laundry, the laundry being at least washed in a
drum which can be driven in rotation using a warmed treatment
liquid, characterized in that treatment liquid for the laundry in
the drum or for other purposes is heated up or warmed alternately
by a heating device. According to the said method, provision is
made for treatment liquid for the laundry to be washed in the drum
or for other purposes to be warmed alternately by the at least one
heating device. As a result, the at least one heating device can be
operated in an uninterrupted manner over relatively long periods of
time, for which reason only the heating power may be changed in
order to adapt to the current conditions. This method is preferably
suitable for gas- and/or oil-operated heating devices which warm or
heat the treatment liquid in accordance with the heat-exchanger
principle. The cost-effectiveness of such heating devices is
improved when they are operated over a relatively long time,
specifically preferably with no interruptions in operation or as
few interruptions in operation as possible.
[0013] In one preferred refinement of the method, treatment liquid
for washing the items of laundry in the drum is first heated by the
at least one heating device. Liquid, in particular treatment
liquid, which is temporarily stored in at least one storage tank
during further operation of the at least one heating device, is
warmed only when the treatment liquid and the laundry have reached
the intended temperature, and further heating-up of the treatment
liquid for washing the respective batch of laundry is no longer
required. The at least one storage tank therefore serves to
buffer-store the thermal energy which continues to be generated by
the heating device between washing operations for successive
batches of laundry. In the period between heating-up of the
treatment liquid of successive batches of laundry, the at least one
heating device can continue to be operated, to be precise possibly
with a reduced or minimum heating power. However, according to the
invention, the at least one heating device does not have to be
switched off between heating-up of the treatment liquid for
successive batches of laundry. Uneconomical interruptions in
operation of the at least one heating device can thus be reduced to
a minimum.
[0014] According to one preferred refinement of the method,
provision is made for the warmed liquid or treatment liquid to be
used in at least one storage tank for washing the laundry into the
drum and/or to prepare the pre-heated treatment liquid for washing
the next batch of laundry. This treatment liquid then needs to be
only slightly heated up, this reducing the cycle time of the
washing machine.
[0015] The invention can be used in a particularly advantageous
manner to heat up treatment liquid which serves for main washing of
the laundry, specifically main-wash liquid. Warming up or heating
the main-wash liquid to the temperature required for the main-wash
operation by at least one gas- and/or oil-heated heating device has
proven particularly cost-effective.
BRIEF SUMMARY OF THE FIGURES
[0016] Preferred exemplary embodiments of the invention are
explained in greater detail below with reference to the drawing, in
which:
[0017] FIG. 1 shows a schematic view of a tunnel-type washing
machine with at least a pre-wash zone, main-wash zone and a rinse
zone.
[0018] FIG. 2 shows a schematic view of a tunnel-type washing
machine with a pre-wash zone and a main-wash zone according to a
second exemplary embodiment of the invention.
[0019] FIG. 3 shows the tunnel-type washing machine according to
FIG. 2 having a plurality of storage tanks according to a third
exemplary embodiment of the invention.
[0020] FIG. 4 shows a schematic view of a spin dryer according to a
fourth exemplary embodiment of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0021] The figures show the various washing machines for commercial
laundries, with which washing machines the method according to the
invention can be carried out. However, the invention is not
restricted to the washing machines shown. Rather, the method
according to the invention is suitable for all types of washing
machines for, in particular, commercial laundries. The washing
machines serve to wash laundry of all types, in particular flat
laundry such as table linen, bed linen and hand towels, any items
of clothing, mats and the like. These articles may include both
white and coloured laundry.
[0022] FIG. 1 shows a tunnel-type washing machine 10 for washing,
specifically pre-washing and main-washing, and for rinsing the
laundry. The tunnel-type washing machine 10 has a cylindrical drum
12 which can be driven in rotation about a horizontal rotation axis
11. A plurality of chambers 13, 14 and 15 which follow one another
along the rotation axis 11 are formed in the drum 12. The
tunnel-type washing machine 10 shown has twelve chambers 13, 14 and
15. However, the invention is not restricted to this. Rather, the
invention is suitable for tunnel-type washing machines 10 with any
desired number of chambers 13, 14 and 15.
[0023] An inlet funnel 16, by way of which the laundry to be washed
enters the drum 12, is located at the start of the drum 12 upstream
of the tunnel-type washing machine 10. A discharge funnel 18 is
provided at that end of the drum 12 which is at the rear as seen in
the treatment direction 17. The washed and rinsed laundry leaves
the tunnel-type washing machine 10 via the discharge funnel 18.
[0024] A water-removal device 19 is provided downstream of the
tunnel-type washing machine 10. The said water-removal device may
be a centrifuge or a water-removal press. The laundry passes from
the drum 12 of the tunnel-type washing machine 10, via the
discharge funnel 18, into the water-removal device 19. The
water-removal device 19 serves to remove a large portion of the
treatment liquid, in particular bound liquor, from the laundry.
[0025] The tunnel-type washing machine 10 shown in FIG. 1 has a
pre-wash zone 20, which is followed in the treatment direction 17
by a main-wash zone 21 and, downstream of this, a rinse zone 22.
The laundry may be subjected to post-treatment, for example
finishing, in the rinse zone 22. Some of the chambers 13, 14 and 15
of the pre-wash zone 20, the main-wash zone 21 and the rinse zone
22 have associated outer drums 23, 24 and 25. These outer drums
serve to supply treatment liquid to the respective chamber and to
drain treatment liquid from the respective chamber.
[0026] The tunnel-type washing machine 10 has an associated heating
device 26. The said heating device is a gas-operated heating device
26 with a gas burner 28. However, heating devices 26 which are
operated with other fossil fuels, for example oil, are also
feasible. The heating device 26 also has a heat exchanger 27. The
heating device 26 therefore constitutes a flow heater. The heat
exchanger 27 can be configured in any desired manner. In FIG. 1,
the heat exchanger 27 is symbolically illustrated as a helical
tube. The helical tubes or heat exchangers 27 are heated by the gas
burner 28 of the heating device 26. The heating device 26, that is
to say the gas burner 28 and the heat exchanger 27, are arranged as
a unit as close as possible next to the tunnel-type washing machine
10, so that only short tube lines are required. However, it is also
feasible to arrange the heating device 26 closely next to the drum
12 and thus integrate it in the frame of the tunnel-type washing
machine 10.
[0027] In the exemplary embodiment shown, the heating device 26 is
intended to heat up the main-wash liquid and the laundry contained
therein. To this end, a return line 29 is passed from the outer
drum 23 of the last chamber 13 of the pre-wash zone 20 to the entry
of the heat exchanger 27 of the heating device 26 in the exemplary
embodiment shown. The warmed treatment liquid which leaves the heat
exchanger 27 is returned to the outer drum 23 of the last chamber
13 of the pre-wash zone 20 via an inflow line 30. Treatment liquid,
to be precise main-wash liquid in this case, which is warmed by the
heating device 26 is therefore conducted in circulation through the
last chamber 13 of the pre-wash zone 20, which chamber is provided
with the outer drum 23. During circulation of the main-wash liquid
and the gradual warming of the said main-wash liquid which takes
place in the process, together with the laundry contained in the
chamber 13, initial main-washing takes place as early as in the
last chamber 13 of the pre-wash zone 20 because the drum 12
continues to be driven in circulation, preferably continuously, as
the main-wash liquid is circulated and warmed up.
[0028] The main-wash liquid warmed by the heating device 26 is
introduced into the bottom of the outer drum 23 by the inflow line
13. Similarly, cooled main-wash liquid is returned to the heating
device 26 at the bottom of the opposite end region, which is at the
front in the treatment direction 17, from the outer drum 23 via the
return line 29. As an alternative, it is feasible to introduce the
warmed main-wash liquid into the top of the outer drum 23. The
inflow line 30 would then issue into the outer drum 23 of the last
chamber 13 of the pre-wash zone 20 from above. It is also feasible
to use the outer drum 24 of the first chamber 14 of the main-wash
zone 21 to warm up the main-wash liquid. In this case, return lines
29 are associated with the outer drum 23 of the last chamber 13 of
the pre-wash zone 20 and the outer drum 24 of the first chamber 14
of the main-wash zone 21, the said return lines leading to the
heating device 26. Similarly, two inflow lines 30 then run from the
heating device 26 to the outer drums 23 and 24. The heating device
26 then supplies the heated main-wash liquid to two outer drums 23
and 24. However, it is also feasible for each outer drum 23 and 24
to have its own associated heating device 26 with in each case a
return line 29 and an inflow line 30. In this case, two circuits
and two heating devices 26 for warming the main-wash liquid are
present in the last chamber 13 of the pre-wash zone 20 and the
first chamber of the main-wash zone 21.
[0029] The tunnel-type washing machine 10 shown has a storage tank
31. A feed line 32 arriving from the water-removal device 19 is led
to the storage tank 31. The liquid, in particular rinse liquid,
which is removed from the laundry by the water-removal device 19
enters the storage tank 31 through the feed line 32. In the
exemplary embodiment shown, a further feed line 33 to the storage
tank 31 is provided, which feed line starts from the first chamber
15 of the rinse zone 22, in particular the first drum 25 of the
rinse zone 22. The said further feed line may be an overflow in the
outer drum 25 or the first chamber 15 of the rinse zone 22. A
corresponding quantity of liquid which is temporarily stored in the
storage tank 31 can be passed to the start of the tunnel-type
washing machine 10, specifically to the inlet funnel 16, from the
storage tank 33 via an outflow line 34 as required. A second
outflow line 35 leads from the storage tank 31 either to the last
chamber 13 of the pre-wash zone 20 or to the first chamber 14 of
the main-wash zone 21.
[0030] Heated treatment liquid can be supplied from the heating
device 26 to the storage tank 31 via an inflow line 36.
Furthermore, a return line 37 leads from the storage tank 31 to the
start of the heating device 26. A second circuit for treatment
liquid which is heated by the heating device 26 is formed between
the heating device 26 and the storage tank 31 as a result.
[0031] The tunnel-type washing machine 10 can have one or else a
plurality of additional heating devices 26 which serve to warm up
treatment liquid at the start of the rinse zone 22 or in the course
of the rinse zone and to warm up the laundry in the said zones. An
inflow line and a return line from the respective heating device
can accordingly be associated with the outer drum 24 at the end of
the main-wash zone or with the outer drum 25 at the start of the
rinse zone 22, however also with an outer drum 25 of the
penultimate chamber 15 of the rinse zone 22 or the last chamber 15
of the rinse zone 22. However, it is also feasible to supply a
plurality of outer drums 23, 24 and/or 25 with heated treatment
liquid in circulation alternately from a single common heating
device 26.
[0032] The method according to the invention is explained below in
conjunction with the tunnel-type washing machine 10 shown in FIG.
1:
[0033] Treatment liquid which is provided for the main-wash
operation in the main-wash zone 21 is initially continuously warmed
by the heating device 26. The main-wash liquid is therefore
continuously warmed up as the drum 12 continues to be driven in
rotation. In the process, the laundry in the last chamber 13 of the
pre-wash zone 20 is also gradually warmed. The main-wash liquid is
warmed in accordance with the continuous-flow principle by constant
circulation of the main-wash liquid conducted through the heat
exchanger 27 of the heating device 26 by pumping. In the process,
the main-wash liquid is circulated from the outer drum 23 of the
last chamber 13 of the pre-wash zone 20, through the inflow line
30, the heat exchanger 27 of the heating device 26 and the return
line 29, back to the outer drum 23. The warmed-up main-wash liquid
is constantly circulated by pumping until the main-wash liquid
upstream of the main-wash zone 21 and the laundry in the main-wash
liquid have reached a prespecified main-wash temperature.
[0034] However, once the main-wash liquid and the laundry contained
therein have reached the prespecified temperature, the heating
device 26 continues to be operated according to the invention. The
treatment liquid in the storage tank 31 is heated by the heating
device 26 in the process. To this end, the treatment liquid in the
storage tank 31 is likewise pumped in circulation from the storage
tank 31, via the return line 37, through the heat exchanger 27 of
the heating device 26 and through the inflow line 36, back to the
storage tank 31. The treatment liquid in the storage tank 31 which
is continuously warmed in accordance with the continuous-flow
principle in this way is used at the specified time to wash a next
batch of laundry into the tunnel-type washing machine 10 and/or to
fill the last chamber 13 of the pre-wash zone 20 or the first
chamber 14 of the main-wash zone 21 with treatment liquid.
[0035] Since the treatment liquid in the storage tank 31 is warmed
at least at the end of the pre-wash zone 20 between successive
phases of warming-up of the main-wash liquid of successive batches
of laundry, continuous operation of the heating device 26, in
particular of the gas burner 28 of the said heating device, is
possible. In this case, the heating power of the gas burner 28 may
be reduced to a minimum, so that the treatment liquid in the
storage tank 31 can be heated-up with a reduced heating power of
the gas burner 28 between successive phases of warming of the
main-wash liquid. The heating power of the gas burner 28 is
designed such that the gas burner 28 can be operated continuously
in the normal case. Operation of gas burner 28 is interrupted only
in exceptional circumstances, for example during operating breaks
in the tunnel-type washing machine 10.
[0036] It is also feasible for the tunnel-type washing machine 10
to have a plurality of associated storage tanks 31. In this case,
the treatment liquid in one of the storage tanks 31 is selectively
heated up when no main-wash liquid is to be heated up by the
heating device 26.
[0037] If the tunnel-type washing machine 10 has a plurality of
heating devices 26, all the heating devices 26 are preferably
operated continuously, these heating devices 26 warming treatment
liquid in one storage tank 31 or else plurality of storage tanks 31
when no rinse liquid or any other treatment liquid in the
tunnel-type washing machine 10 is to be heated up, in order to thus
temporarily store or buffer-store the liquid warmed by the
continuously operated heating devices.
[0038] In cases where not only the main-wash liquid, but also rinse
liquid or water-removal liquid, is to be continuously warmed by the
heating device 26, it is also feasible to use the same heating
device 26 to warm up or heat up the main-wash liquid, the rinse
liquid and possibly the finishing liquid in succession. In such a
case, it may become unnecessary to temporarily store the treatment
liquid in at least one storage tank 31 for buffer-storing the
energy generated by the gas burner 28.
[0039] FIG. 2 shows a tunnel-type washing machine 38 which serves
only to wash, specifically to pre-wash and main-wash, the laundry.
The laundry is rinsed in a water-removal device 39 which is
arranged downstream of the tunnel-type washing machine 38. The
water-removal device 39 may be a centrifuge or a press which rinses
the laundry and then removes water from it. The tunnel-type washing
machine 38 also has a cylindrical drum 41 which can be driven in
rotation about a horizontal rotation axis 40. A plurality of
chambers 42, 43 which follow one another along the rotation axis 40
are arranged in the drum 41. The tunnel-type washing machine shown
has five chambers 42, 43. However, the invention is not restricted
to this.
[0040] An inflow funnel 44, via which the laundry to be washed
enters the drum 41, is located at the start of the drum 41 upstream
of the tunnel-type washing machine 38. A discharge funnel 45 is
provided at that end of the drum 41 which is at the rear as seen in
the treatment direction 17. The washed laundry leaves the
tunnel-type washing machine 38 via this discharge funnel.
[0041] The tunnel-type washing machine 38 shown in FIG. 2 has only
a pre-wash zone 46 and a main-wash zone 47 which follows in the
treatment direction 17. The last chamber 42 of the pre-wash zone 46
has an associated stationary outer drum 48. The last chamber 43 of
the main-wash zone 47 has a further outer drum 49. Dirty pre-wash
water can be drained from the last chamber 42 of the pre-wash zone
46 via the outer drum 48, before main-wash liquid is conducted into
the drum 41 into this chamber 42 via the outer drum 48. Similarly,
the main-wash liquid can be discharged via the last outer drum
49.
[0042] The tunnel-type washing machine 38 has an associated heating
device 50. This heating device can be arranged next to the
tunnel-type washing machine 38 or else be integrated in the said
tunnel-type washing machine. The heating device 50 is in the form
of a flow heater, for which reason it has a gas burner 51 and a
heat exchanger 52. The treatment liquid which is to be warmed up is
continuously pumped through the heat exchanger 52 which is
illustrated symbolically as a helical tube in FIG. 3. In the
exemplary embodiment shown, the treatment liquid is main-wash
liquid. Warmed main-wash liquid is conducted from the heat
exchanger 52 of the heating device 50, via an inflow line 53, into
the lower region of the outer drum 48 of the last chamber 42 of the
pre-wash zone 46. However, as an alternative, warmed treatment
liquid can also be conducted into the chamber 42 from above. Cooler
or cooled main-wash liquid is conducted back to the start of the
heat exchanger 52 of the heating device 50 from the outer drum 48
of the last chamber 42 of the pre-wash zone 46 via a return line
54. The outer drum 48 of the last chamber 42 of the pre-wash zone
46, the inflow line 53, the return line 54 and the heat exchanger
52 therefore form a closed circuit for the main-wash liquid which
is warmed by the gas burner 51.
[0043] The tunnel-type washing machine 38 has a storage tank 55.
The storage tank 55 accommodates the liquid separated off from the
laundry by the water-removal device 39 during the water-removal
operation, the said liquid being rinse liquid. To this end, a feed
line 56 leads from the water-removal device 39 to the storage tank
55. The liquid stored in the storage tank 55 can be fed from the
storage tank 55, via a discharge line 57, to the start of the drum
41, to the inlet funnel 44 in the exemplary embodiment shown. As an
alternative, treatment liquid can be supplied from the storage tank
55 to the last chamber 42 of the pre-wash zone 46 via an outflow
line 58. For example, at least a portion of the main-wash liquid,
to be precise as already pre-heated main-wash liquid, can be
supplied from the storage tank 55 through the outflow line 58 after
draining of the pre-wash liquid from the outer drum 48 of the
chamber 42.
[0044] A further inflow line 59 leads from the heat exchanger 52 of
the heating device 50 to the storage tank 55. Furthermore, a return
line 60 returns to the heat exchanger 52 of the heating device 50
from the storage tank 55.
[0045] The tunnel-type washing machine 38 likewise operates in
accordance with the method according to the invention, to be
precise in principle as described in conjunction with the
tunnel-type washing machine 10 of the exemplary embodiment of FIG.
1. Accordingly, the heating device 50 is also operated
continuously, or at least mainly continuously. The main-wash liquid
in the last chamber 42 of the pre-wash zone 46 is initially
continuously warmed since main-wash liquid which is warmed by the
heating device 50 is continually pumped through the outer drum 48
and the last chamber 42 of the pre-wash zone 46 via the inflow line
53 and the return line 54. The main-wash liquid warmed in the
heating device 50 is constantly circulated in order to warm up the
main-wash liquid and the laundry contained in the chamber 42 to the
main-wash temperature in the last chamber 42 of the pre-wash zone
46. In this case, the main-wash liquid is continuously warmed by
the heating device 50, so that the heating device 50--like all the
other heating devices--constitutes a flow heater.
[0046] When the main-wash liquid and the laundry contained therein
are at the intended main-wash temperature, the heating device 50
continues to be operated until the main-wash liquid for the next
batch of laundry is heated, this possibly being done with a
restricted heating power of the gas burner 51. During this further
operation of the heating device 50, the treatment liquid in the
storage tank 55 is warmed, as it were, as a buffer store for
storing the energy generated by the gas burner 51 between two
successive batches of laundry. To this end, the treatment liquid in
the storage tank 55 is continuously circulated from the heat
exchanger 52, through the inflow line 59, to the storage tank 55
and back to the heat exchanger 52 of the heating device 50 via the
return line 60. This second treatment-liquid circuit of the heating
device 50 is operated when no main-wash liquid is warmed in the
last chamber 42 of the pre-wash zone 46 between two successive
batches of laundry. The warmed treatment liquid in the temporary
storage means 50 can be conducted either to the start of the
tunnel-type washing machine 38 via the outflow line 57 and there be
used to wash-in the laundry to be washed or it serves to fill the
outer drum 48 of the last chamber 42 of the pre-wash zone 46 with
pre-heated main-wash liquid. On account of the pre-heating in the
storage tank 55, this main-wash liquid is at a temperature which
corresponds to the main-wash temperature, but may also be below
this.
[0047] The exemplary embodiment of FIG. 3 differs from the
exemplary embodiment of FIG. 2 only in that the tunnel-type washing
machine 38 and the water-removal device 39 have an associated
second storage tank 61. Otherwise, the tunnel-type washing machine
38, the water-removal device 39 and the heating device 50
correspond to the exemplary embodiment of FIG. 2, for which reason
identical reference numerals are used for identical parts.
[0048] The treatment liquid which is separated off from the laundry
by the water-removal device 39 and which contains, in particular, a
large portion of the liquor bound in the laundry, in particular
rinse liquid, is supplied either to the storage tank 55 or 61 via a
branched feed line 56. To this end, the feed line has two parallel
feed line sections 62 and 63 which lead firstly to the storage tank
55 and secondly to the storage tank 61. By virtue of valves in the
feed line sections 62 and 63, it is possible to determine which of
the two storage tanks 55 or 61 the liquid, in particular rinse
liquid, is conducted into from the water-removal device 39.
[0049] Only one discharge line 64 to the discharge line 57 leads
from the additional storage tank 61 to the inlet funnel 44 upstream
of the tunnel-type washing machine 38.
[0050] The cold water-removal liquid, which originates from the
water-removal device 39 and is preferably at approximately room
temperature, is warmed by the heating device 50 in the storage tank
55, as described in conjunction with FIG. 2, specifically between
heating-up of main-wash liquid between two successive batches of
laundry. In contrast, the water-removal liquid in the storage tank
61 cannot be pre-heated by the heating device 50. Therefore, the
storage tank 55 contains warmer treatment liquid, in particular
water-removal liquid, than storage tank 61. As a result, the inflow
funnel 44 at the start of the tunnel-type washing machine 38 can be
supplied with relatively cold treatment liquid from the storage
tank 61 and pre-heated treatment liquid from the storage tank 55.
The treatment liquid from the two storage tanks 55 and 61 can be
mixed by virtue of corresponding valves downstream of the storage
tanks 55 and 61, in order to provide the treatment liquid for
washing the laundry into the tunnel-type washing machine 38 with a
desired temperature, in particular a lower temperature than the
treatment liquid in the storage tank 55 heated up by the heating
device 50.
[0051] In the exemplary embodiment of FIG. 4, the method according
to the invention is described in conjunction with a washer-dryer
65. The washer-dryer 65 has a drum 66 which can be driven in
rotation and has a single chamber. The drum 66 is surrounded by a
stationary outer drum 70 with a common loading and unloading
opening. The outer drum 70, together with the rotatable drum 66
mounted therein, can be pivoted about an axis which runs transverse
to the rotation axis of the drum during treatment of the laundry.
The laundry is the subjected to pre-washing, main-washing, rinsing
and water-removal in the single chamber of the drum 66.
[0052] The washer-dryer 65 has its own associated heating device 67
which, like the heating devices described above, has a gas burner
68 and a heat exchanger 69.
[0053] An inflow line 71 for treatment liquid which is warmed by
the heating device 67 is led to the stationary outer drum 70 of the
washer-dryer 65. Cooled treatment liquid, in particular main-wash
liquid, is returned from the outer drum 70 of the washer-dryer 65
to the start of the heat exchanger 69 of the heating device 67 via
a return line 72.
[0054] The washer-dryer 65 shown here has two associated storage
tanks 73, 74. The storage tanks 73, 74 accommodate the treatment
liquid, in particular water-removal liquid which is produced when
the laundry is spun in the washer-dryer 65. The water-removal
liquid, this possibly also being rinse liquid, can be supplied
selectively to one or the other storage tank 73 or 74 via a feed
line 75 with two feed line sections 76, 77.
[0055] An inflow line 78 and a return line 79 are associated with
one of the storage tanks, specifically the storage tank 74. This
creates a second circuit which is connected to the storage tank 74
for treatment liquid which is pre-heated or heated by the heating
device 67.
[0056] An alternative exemplary embodiment is feasible, in which
the washer-dryer 65 has more than two associated storage tanks 73
and 74, to be precise for treatment liquid which is intended for
coloured laundry on the one hand and for white laundry on the
other. In this case, the apparatus can have two storage tanks 73,
74 for coloured laundry and two storage tanks 73, 74 for white
laundry. This alternative also applies to the three exemplary
embodiments of the invention described above.
[0057] According to a further alternative of the exemplary
embodiment of FIG. 4, the storage tank 73 can be dispensed with, so
that the washer-dryer 65 has only one associated storage tank 74,
it being possible for the water-removal liquid contained in the
said storage tank to be preheated or heated up by the heating
device 67, to be precise up to the temperature of the main-wash
liquid. As an alternative, the washer-dryer 65 can have two
associated storage tanks 74, to be precise for coloured laundry and
for white laundry. In this case, the treatment liquid in the two
storage containers 74 (for the coloured laundry and the white
laundry) can be heated up together or alternately by the heating
device 67.
[0058] The method according to the invention proceeds with the
washer-dryer 65 shown in FIG. 4, in principle, in exactly the same
way as with the tunnel-type washing machine 38 of the exemplary
embodiment of FIG. 3.
[0059] In the case of the washer-dryer 65, the pre-washed liquid is
first drained from the drum 66 and the drum 66 is filled with
main-wash liquid, to be precise possibly from the storage tank 74
which contains treatment liquid which is pre-heated by the heating
device 67, after pre-washing. This treatment liquid does not yet
all have to be at the temperature of the main-wash liquid. After
the drum 66 of the washer-dryer 65 is filled with main-wash liquid,
main-wash liquid which is heated by the heating device 67 by virtue
of a continuous-flow method is pumped in circulation through the
drum 66, that is to say is circulated. In the process, the
treatment liquid is heated to the intended temperature and at the
same time the laundry contained in the treatment liquid is warmed
up to the main-wash temperature.
[0060] After the main-wash liquid of the laundry in the drum 66 has
reached the intended main-wash temperature, circulation of the
main-wash liquid through the drum 66 is interrupted. However, the
heating device 67 continues to be operated, it being possible to
reduce the heating power of the gas burner 68. Until the main-wash
liquid for the next batch of laundry in the washer-dryer 65 is
warmed, the treatment liquid in the storage container 74 is
circulated through the inflow line 78, which is connected to the
storage tank 74, and the return line 79 and in the process
continuously warmed by the heat exchanger 69 of the heating device
67. This continues until the main-wash liquid for the next batch of
laundry is to be warmed in the washer-dryer 65.
[0061] Therefore, even in the exemplary embodiment of FIG. 4, the
gas burner 68 of the heating device 67 is operated in an
uninterrupted manner as long as successive batches of laundry are
to be treated in the washer-dryer 65. On account of the continuous
operation of the heating device 67, the gas burner 68 does not have
to be switched off in the phases in which no main-wash liquid is to
be heated, that is to say between successive batches of laundry
which are to be treated in the washer-dryer 65. At most, the
heating power of the gas burner 68 is restricted between two
successive batches of laundry. The gas burner 68 can therefore be
continuously operated by treatment liquid in the storage container
74 being warmed between successive batches of laundry and then
being used for filling the drum 66 of the washer-dryer 65 with new
main-wash liquid, but also for washing the laundry into the drum 66
of the washer-dryer 65.
[0062] The invention is not restricted to the heating devices
described above. The invention can also be realized with other flow
heaters. It is also feasible, within the scope of the invention, to
use burners which operate with other fossil fuels, for example oil,
or else burners which can be selectively operated with various
fossil fuels, in place of the gas burners.
LIST OF REFERENCE SYMBOLS
[0063] 10 Tunnel-type washing machine [0064] 11 Rotation axis
[0065] 12 Drum [0066] 13 Chamber [0067] 14 Chamber [0068] 15
Chamber [0069] 16 Inlet funnel [0070] 17 Treatment device [0071] 18
Discharge funnel [0072] 19 Water-removal device [0073] 20 Pre-wash
zone [0074] 21 Main-wash zone [0075] 22 Rinse zone [0076] 23 Outer
drum [0077] 24 Outer drum [0078] 25 Outer drum [0079] 26 Heating
device [0080] 27 Heat exchanger [0081] 28 Gas burner [0082] 29
Return line [0083] 30 Inflow line [0084] 31 Storage tank [0085] 32
Feed line [0086] 33 Feed line [0087] 34 Outflow line [0088] 35
Outflow line [0089] 36 Inflow line [0090] 37 Return line [0091] 38
Tunnel-type washing machine [0092] 39 Water-removal device [0093]
40 Rotation axis [0094] 41 Drum [0095] 42 Chamber [0096] 43 Chamber
[0097] 44 Inlet funnel [0098] 45 Discharge funnel [0099] 46
Pre-wash zone [0100] 47 Main-wash zone [0101] 48 Outer drum [0102]
49 Outer drum [0103] 50 Heating device [0104] 51 Gas burner [0105]
52 Heat exchanger [0106] 53 Inflow line [0107] 54 Return line
[0108] 55 Storage tank [0109] 56 Feed line [0110] 57 Outflow line
[0111] 58 Outflow line [0112] 59 Inflow line [0113] 60 Return line
[0114] 61 Storage tank [0115] 62 Feed line section [0116] 63 Feed
line section [0117] 64 Outflow line [0118] 65 Spin dryer [0119] 66
Drum [0120] 67 Heating device [0121] 68 Gas burner [0122] 69 Heat
exchanger [0123] 70 Outer drum [0124] 71 Inflow line [0125] 72
Return line [0126] 73 Storage tank [0127] 74 Storage tank [0128] 75
Feed line [0129] 76 Feed line section [0130] 77 Feed line section
[0131] 78 Inflow line [0132] 79 Return line
* * * * *