EP1982631A2 - Cycle dish washers with regulated drying - Google Patents

Abstract

The washing machine for cleaning laundry items (9, 10) has at least one washing zone (3, 4), at least one rinsing zone (5, 6), a drying zone (7) and a transporting device to take the laundry through the machine. It has at least one fan (19), the load of which can be adjusted during the operation of the washing machine.

Description

Technical area

The invention relates to a cleaning machine, in particular a continuous dishwasher, for to be cleaned Good, such as. Dishes.

State of the art

Cleaning machines, in particular continuous dishwashers, e.g. for cleaning the costs incurred in catering, to be cleaned dishes, tray and container parts are known. While domestic dishwashers generally run through a program sequence with the successive cleaning steps in a stationary arrangement of the dishes and cutlery to be cleaned, the treatment zones are arranged successively in continuous dishwashers and the items to be cleaned or the good to be cleaned from the inlet area transported by the successive to be traversed treatment zones to the removal area.

Continuous dishwashers known from the prior art have at least four treatment zones between inlet region and outlet region. A conveyor promotes the items to be washed through the treatment zones. This is a pre-cleaning zone (pre-clearing), at least one cleaning zone, a final rinse zone and a drying zone. In the pre-cleaning zone (pre-clearing) easily adhering dirt is removed from the material to be cleaned. For this purpose, rinsing liquid is sucked by a pump from the storage tank associated with this treatment zone and sprayed over the material to be cleaned by appropriately trained nozzles. Then the rinsing liquid flows back into the storage tank and is there again by a Suction pump sucked and introduced into the circulation. Usually, the storage tank is covered by sieves to retain larger dirt particles from the rinse liquid.

In the at least one cleaning zone, which adjoins the pre-cleaning zone (pre-clearing), dirt particles adhering to the items to be washed are still removed from the items to be washed by means of a usually alkaline rinsing liquid. For this purpose, the heated rinsing liquid is sucked by a further circulating pump from the storage tank associated storage tank and sprayed over the items to be washed by means of suitably positioned and oriented nozzles. Subsequently, the rinsing liquid flows back into the corresponding storage tank and is sucked in again by the circulation pump. Usually, the storage tank is covered by sieves in order to retain coarser dirt particles from the rinsing liquid.

As a result of the usually heated rinsing liquid, during the spraying of the same within the respective treatment zone of the automatic cleaning machine steam puffs (vapor) are produced. It is important to keep the vapors and thus their energy content as possible in this treatment zone in order to avoid running out of heat energy in this way from this zone.

In the final rinse zone, which adjoins the at least one cleaning zone, the alkaline rinsing liquid, which wets the surface of the ware, rinsed off together with any leftovers of food from the surface of the ware by means of hot fresh water to which a rinse aid is usually added. In certain embodiments of the rinsing zone, the fresh water is again collected after this treatment step in a storage tank associated with this treatment zone and sucked with a circulating pump associated with this treatment zone and distributed before the actual fresh water rinsing by means of nozzles on the dishes. Subsequently, the rinsing liquid flows back into the storage tank and is sucked in there again by the circulation pump. Due to the elevated temperature of the heated water and the fine spraying by means of the spray nozzles also arise steam fumes (vapors) in this zone. Analogously to the at least one cleaning zone, it is also important here to keep the vapors and thus their energy content as far as possible in the respective treatment zone, in this case the final rinse zone, in order to avoid the execution of thermal energy from this zone in this way.

During the rinsing process in the rinsing liquid-carrying process steps arise high-energy vapor (vapor) and moist, warm air, which are passed within the cleaning machine to at least one device for heat recovery and then discharged from the machine.

In the drying zone adjoining the final rinse zone, heated air is blown onto the washware via outlet nozzles by means of a blower. The fans are designed so that high air velocities can be achieved at the outlet nozzle. As a result, the washing liquid remaining on the items to be washed is partially removed by being blown off and partly by evaporation from the items to be washed. Ideally, the heated air in the drying zone should be recirculated and unwanted air flows in the direction of the adjacent zone, in particular the final rinse zone and the outlet area or the removal area of the cleaning machine should be avoided. These flows can be influenced by the type of ware itself and the design of the drying zone. The fact that the air flow remains within the drying zone is usually achieved by means disposed within the conveyor Luftumlenkwannen. The conveyor is e.g. to an endlessly designed conveyor belt, which promotes the cleaning material continuously or with the interposition of transport breaks through the treatment zones of the cleaning machine described above.

The air flow emerging from the outlet nozzle of the blower impinges on the air deflection tubs which are formed below the conveying means and divides the air flow essentially into a partial flow directed towards the inlet region and towards the outlet region of the cleaning machine. Through the usually U-shaped formed Luftumlenkwanne both partial flows are deflected upward and led back to the blower to be sucked in there again and blown over the dishes. Since the recirculated air in the drying zone absorbs the moisture of the cleaned items and thus becomes moister, so that worse can absorb more moisture, it must be partially replaced by fresh air from the environment. This is achieved by generating a flow in the direction of a suction point within the cleaning machine by suitable devices and a partial amount of air is removed from the machine. At the same time, fresh air flows into the drying zone and replaces some of the air circulated in the drying zone.

Out DE 10 2004 003 797 A1 is a continuous dishwasher with multiple treatment zones known. The flow direction of the exhaust air inside the cleaning machines runs from the outlet to the inlet counter to the transport direction of the items to be washed by the dishwasher, wherein the suction point is arranged in the region of the inlet region of the dishwasher. The volumes of air withdrawn from the drying zone may be varied by adjustable positions of discharge nozzles of the fan of the drying zone.

The known from the prior art machines are designed such that the Luftumlenkwannen and the resulting air currents are designed for a particular, preferably ideal, operating condition. This ideal operating condition is only given if the items to be washed, e.g. Plates and trays, vertically in the designated conveying medium, the conveyor belt preferably used is positioned because only in this state, the air conveyed by the fan can impinge on the located under the pumped medium Luftumlenkwanne and this is then fed back to the blower.

In contrast to the above-mentioned operating state, which corresponds to the ideal operating state, however, special operating states are possible in which e.g. Container, trays lying on the medium or long, flat items to be cleaned are transported through the various treatment zones of the continuous dishwasher for cleaning. These special operating conditions can occur at irregular intervals during the normal operating state. Due to longer items to be cleaned, the air deflection trough located below the conveyor is completely or partially covered by the drying zone during the transport of the items to be cleaned. Thus, the function of Luftumlenkwanne, namely, to circulate the air, completely or partially canceled. Upon impact of the air flow exiting through the fan at high speed on the cleaning material underneath, e.g. Container or lying trays, this is divided into sub-streams, which are directed towards the outlet (take-off point of the goods to be cleaned from the conveyor belt) and / or adjacent to the drying zone, the rinse zone.

The one partial flow, which is directed in the direction of rinsing, causes an air flow through the entire continuous dishwasher in the direction of the inlet region of the cleaning machine and allows high-energy, warm and moist air and steam swirls (vapors) emerge at the inlet region. This means that the room climate in the installation room of the cleaning machine is adversely affected, since the humidity increases in this.

The other partial flow, which is directed towards the outlet region of the cleaning machine, disadvantageously causes high-energy, warm, moist air from the drying zone to the removal distance of the cleaning material, i. flows into the installation room of the cleaning machine and its climate adversely affected by the humidity increases. In addition, vapor, i. Steam billow, flow from the final rinse zone in the drying zone. This is accompanied by the disadvantage that in this way a great deal of moisture is introduced into the drying zone and into the air circulated within the drying zone. This in turn has the consequence that the drying result of the subsequent cleaning material is significantly deteriorated.

The solution outlined above, which makes use of air deflection tanks, has the disadvantage that in the case of temporary, special operating conditions, e.g. in trays transported on the preferably endlessly formed transport medium or trays resting on the endless transport medium due to the escape of vapor, i. Steam billowing, energy leaking out of the continuous dishwasher. For the operator of such continuous-flow dishwashers, this means an increased energy requirement in order to cover the energy losses again. In addition, by the exiting, high-energy vapors operating personnel in the inlet area, i. the placement area of the preferably endless transport medium, and in the acceptance area, i. exposed to increased loads during removal of the cleaned material from the endless transport medium.

Disclosure of the invention

The present invention is based on the disadvantages of the prior art outlined the task, the drying zone of a cleaning machine, in particular a continuous dishwasher, so that by special operating conditions only small or no unwanted air currents and thus high-energy vapor streams (vapors) in adjacent treatment zones and / or get into the room in which the cleaning machine, which is preferably a continuous dishwasher, is set up.

According to the invention, this object is solved by the features of independent claim 1.

Following the solution proposed by the invention, the speed of the fan, which promotes air within the drying zone in the circulation, according to the regulated the respectively in the drying zone located washware caused operating state.

The achievable with the proposed solution according to the invention are mainly in the fact that the high-energy vapor (vapor) and thus warm, moist air by reducing the speed of the fan of the drying zone in the case of a special operating condition or only to a small extent by the inlet area or the outlet region of the cleaning machine, which is preferably a continuous dishwasher escapes. In addition, by reducing the speed of the fan within the drying time is achieved that the air flow in the drying zone can be better recirculated. This has the advantageous effect that no or only a small amount of vapor (vapor) passes from the rinse zone upstream of the drying zone into the drying zone itself and thus ensures that a sufficient amount of dry air is always available within the drying zone Able to absorb moisture of the items to be dried.

The control of the cleaning machine, which is preferably a continuous-flow dishwasher, is able to recognize whether and when a special operating state is present in the sense outlined above. A special operating state can be given, for example, in that containers, trays lying on the conveying medium, or long items to be washed are transported for cleaning by the cleaning machine. This special operating state can occur at irregular intervals, during normal operation as a single event or several times in succession. By appropriately trained sensors, such as moisture sensors, differential pressure switch, flow sensors or the like, this special operating state is detected and transmitted to the control of the cleaning machine. As soon as this special operating state is detected by the machine control, a reduction of the speed of the fan and thus a reduction of the flow rate and the air volume of the exiting at the outlet nozzle of the fan air flow into the drying zone to a predetermined value, which is stored in the machine control. The lower and thus slowed down in terms of its flow velocity air flow effected in an advantageous manner when hitting the goods to be cleaned, smaller partial flows in the direction of the adjacent zones, ie the removal area at the end of Durchlaufgeschirrspülautomaten or, upstream of the drying zone, rinse. Since the now occurring partial flows have a much lower flow velocity, it is possible to guide them within the drying zone in the circuit and thus to avoid escape of the same from the drying zone in the above-mentioned adjacent zones.

Furthermore, the machine control of the cleaning machine, which is preferably a continuous-flow dishwasher, is capable of detecting at least one moisture sensor and / or at least one temperature sensor provided there and / or at least one pressure sensor arranged there, depending on the drying zone attached Whether and when a special operating state of the continuous dishwasher is no longer present. If the machine controller has recognized this state, the transition from the special operating state to the normal operating state, the speed of the fan and thus the speed and the air volume of the airflow exiting the outlet nozzle of the fan can be increased again to the value set before the reduction.

Brief description of the drawings

With reference to the drawing, the invention will be described below in more detail.

Figur 1

eine schematisch wiedergegebene Darstellung einer Ausführungsform der erfindungsgemäß vorgeschlagenen Durchlaufspülmaschine,

Figur 2

eine Trocknungszone, in welcher die Erkennung eines Sonderbetriebszustands dargestellt ist,

It shows:

FIG. 1

1 is a schematic representation of an embodiment of the continuous-flow dishwasher proposed according to the invention;

FIG. 2

a drying zone, in which the detection of a special operating state is shown,

embodiments

The representation according to FIG. 1 is a schematic reproduced embodiment of the present invention proposed continuous flow dishwasher.

In this occur by differently shaped items to be washed 9, 10 at irregular intervals different operating conditions. The transport of the ware 9, 10 takes place in the in FIG. 1 This conveyor belt 11 is preferably used as an endless circulating medium to the items to be washed 9, 10 through different treatment zones of in FIG. 1 transported throughput dishwasher to transport.

On the conveyor belt 11 is on the one hand ware 10, such. set trays and / or plates, which represent a normal operating condition. On the other hand is also on the conveyor belt 11 items 9, such. Container and / or long items to be washed, which leads through the respective configuration to a special operating state of the continuous dishwasher.

At an inlet 1 runs on the top of the conveyor belt 11 recorded items to be washed 9, 10 in an inlet tunnel 2 a. The inlet tunnel 2 is shielded by means of a separation curtain 13 to the outside, to prevent the escape of vapor swirl in the region of the inlet 1 of the continuous dishwasher. After the washware 9, 10, which is transported on the upper side of the conveyor belt 11 and which is transported in the transport direction 12, has passed through the inlet tunnel 2, it is transported into a pre-wash zone 3. Within the pre-rinse zone 3 (pre-clearing), a pre-rinse system 15 is arranged. This pre-rinsing system 15 has at least one spray pipe, preferably a plurality of spray pipes, which are arranged on the underside or above the circulating conveyor belt 11 in this zone. About one in FIG. 1 not shown pump, the pre-rinsing system 15 is applied with cleaning fluid and sprayed by means of the spray pipes and the spray arms on the dishes. The pre-rinsing zone 3 is separated by a further separating curtain 13 from a subsequent rinsing zone 4.

After the items to be washed 9, 10 has left the pre-rinsing zone 3, this enters a subsequent rinsing zone 4. Also, the subsequent rinsing zone 4 comprises at least one rinsing system 16, which is arranged above and below the top of the circulating conveyor belt 11. The at least one rinsing zone 4 is likewise associated with a pump which is variably controllable in terms of its pump capacity and by means of which cleaning fluid is applied to the spray tubes of the rinsing system 16. The rinsing zone 4 is separated by a further separating curtain 13 from a pump rinsing zone 5, which has a spraying system arranged above and below the upper side of the conveyor belt 11 in the form of two spray pipes 17 located opposite one another. The pump rinsing zone 5 is followed by a fresh water rinsing zone 6. Within the Frischwasserklarspülzone 6, the items to be washed 9, 10 rinsed with fresh water to remove any remaining impurities or the previously applied cleaning fluid before entering the items to be washed 9, 10 in a drying zone 7 of this. Downstream of the fresh water rinsing zone 6, there is a further separating curtain 13, which separates the fresh water rinsing zone 6 from the drying zone 7. Within the drying zone 7, which is followed by a removal path 8, there is a drying fan 19. This drying fan 19 sucks air from the drying zone 7, this leads via a heater not shown to an outlet nozzle 20. The heated in the drying fan 19 and the subsequent heaters or heated air is accelerated into the outlet nozzle 20, and at high speed in Direction to the drying zone 7 passing, cleaned and clear rinsed items 9, 10 directed. In the lower region of the drying zone 7 is a Luftumlenkwanne 21, which in the normal operating condition, ie when normal items to be washed 10 is transported through the drying zone, which in the exit direction 23 from the outlet nozzle 20 emerging hot air in the flow direction 30 deflects, so that these again the drying fan 19th flows in. Seen in the transport direction 12, the drying zone 7 is shielded by a further separation curtain 13 against the removal path 8. The separation curtains 13 located in the continuous-flow dishwasher prevent steam swirls (vapor) or spray water from reaching adjacent zones and / or the feed line 1 or removal line 8. As a result, energy-efficient operation can be achieved in the normal operating state of the continuous-flow dishwasher, since the higher-temperature vapor streams (vapors) can be kept within the respective treatment zones 3, 4, 5, 6 and leave the continuous-flow dishwasher.

From the illustration according to FIG. 2 can be a special operating condition, which is caused by not ideal designed dishes, take.

The representation according to FIG. 2 can be removed that items to be washed 9, which represents special rinse in the present case, lying in the transport direction 12, is transported on the conveyor belt 11 of the fresh water rinsing 6 in the drying zone 7. Due to the length and the closed design surface of the ware 9 located below the drying zone 7 Luftumlenkwanne 21 is first partially and after a short transport time in the longitudinal direction, ie in the transport direction extending Sonderspülgutes 9 completely covered by this. The on the, here Sonderspülgut representing, items to be washed 9 at high speed impinging, exiting through the outlet nozzle 20 air flow 23 is divided into a first partial flow 24 and a further, second partial flow 25. Due to the still high speed of the first partial flow 24 and the lack of deflection of the partial flow 24 upwards from the fresh water rinse 6 moist, hot air (vapor) in the, this downstream, drying zone 7 entrained. By mounted in the drying zone 7 at a suitable location sensors, which may be, for example, at least one moisture sensor 26 and / or at least one temperature sensor 27, it is possible for the machine control 29 through the first part stream 24 in combination with the Sonderspülgut 9 caused increase in temperature or humidity in the drying zone. Depending on these signals, the controller 29 can detect the presence of a special operating state in which the power of the fan 19 of the drying zone 7 and thus the air volume exiting therefrom and the flow velocity of the air flow 23 are reduced to a predetermined value. If the air stream 23, reduced to a special operating state by the machine controller 29, then reaches the special washing material 9, it divides into a small first partial stream 24 and a smaller second partial stream 25. It is thereby achieved that the smaller first and second partial streams 24, 25 can be circulated within the drying zone 7 without steam billowing (vapor) being introduced from the fresh water rinsing zone 6 into the drying zone 7 arranged downstream of the latter, although the air in the deflection tank 21 is covered by the Sonderspülgut 9. In addition, it is achieved that within the drying zone 7 always a sufficient amount of dry air is available, which is able to absorb moisture of both the normal ware 10 and also to be dried ware 9.

In a further embodiment of the drying zone 7 downstream of the fresh water rinsing zone 6, the controller 29 may be replaced by a suitable place, e.g. in the region of the Luftumlenkwanne 21 mounted pressure sensor the special operating condition by special Spülgut 9, such. Container, lying trays, long dishes, caused, recognize. When driving over the Luftumlenkwanne 21 through the Sonderspülgut 9 the emerging at high speed from the outlet nozzle 20 air flow 23, which extends between the drying fan 19 and the Luftumlenkwanne 21, interrupted. A resulting pressure difference is detected by the pressure sensor 28 and transmitted to the controller 29. Depending on this pressure difference, which is now present in the controller 29, this can detect the presence of a special operating state in which the power of the fan 19 of the drying zone 7 and thus the air volume and the speed of the exiting the drying fan 19 air flow 23 to a predetermined , stored in the controller 29 value is reduced.

The end of the special operating state may be over a time period and / or introduced in the drying zone 7 at a suitable location sensors 26, 27, 28, which may be at least one humidity sensor 26, at least one temperature sensor 27 or the addressed at least one pressure sensor 28 be arranged.

Although in the illustration the continuous dishwashing machine according to FIG. 1 is shown with a circumferentially formed, endless conveyor belt 11, instead of this revolving conveyor belt 11, the passage of the items to be washed 9, 10 in the transport direction 12 through the conveyor dishwasher also by using transport baskets, which are conveyed by means of a chain or a latch rail through the conveyor dishwasher , In the FIG. 1 The continuous-flow dishwasher shown comprises a pre-rinsing zone 3 (pre-clearing) and the pump rinsing zone 5, both of which are not absolutely necessary, as well as the fresh-water rinsing zone 6. It is essential that the special operating conditions are determined by sensors 26, 27 mounted in suitable locations in the drying zone 7 , 28 are detected and by taking appropriate countermeasures, such as the speed control of the drying fan 19, the escape of high-energy and moist vapor swirls (vapors) can be prevented from the continuous dishwasher.

LIST OF REFERENCE NUMBERS

1

Enema (task area)

2

entry tunnel

3

pre-wash zone

4

rinse zone

5

pump-action

6

clean-water

7

drying zone

8th

Outlet (removal area)

9

Sonderspülgut

10

normal dishes

11

conveyor belt

12

transport direction

13

curtain

14

Heat recovery

15

prewash

16

flushing system

17

Flushing system pump flushing

18

Rinsing system Fresh water rinsing

19

drying fan

20

Outlet nozzle of the blower 19

21

Luftumlenkwanne

22

outlet opening

23

Air flow from the drying nozzle

24

first partial flow

25

second partial flow

26

Humidity Sensor

27

temperature sensor

28

Differential Pressure Sensor

29

machine control

30

Counter air flow from the Luftumlenkwanne 21st

Claims (10)

A through-flow dishwasher for cleaning items to be washed (9, 10) having at least one rinse zone (3, 4), at least one final rinse zone (5, 6), a drying zone (7) and a transport device (11) for conveying the items to be washed (9, 10) Transport direction (12) through the continuous dishwasher, characterized in that at least one fan (19) of the drying zone (7) is adjustable in terms of its speed. Continuous dishwasher according to claim 1, characterized in that the speed of the at least one in the drying zone (7) arranged fan (19) depending on the items to be washed (9, 10) is regulated. Continuous dishwasher according to claim 1, characterized in that sensors (26, 27, 28) air flows, which emerge from the drying zone (7) and are directed in or against the transport direction (12) of the ware (9, 10) detect. Continuous dishwasher according to claim 3, characterized in that the sensor for detecting an air flow in or against the transport direction (12) is designed as a differential pressure sensor (28). Continuous dishwasher according to claim 3, characterized in that the sensor for detecting an air flow in or against the transport direction (12) is designed as a humidity sensor (26). Continuous dishwasher according to claim 3, characterized in that the sensor for detecting an air flow in or against the transport direction (12) is designed as a temperature sensor (27). Continuous dishwasher according to claim 3, characterized in that the sensor for detecting an air flow in or against the transport direction 12 is formed as an air anemometer. Continuous dishwasher according to claim 1, characterized in that from the at least one blower (19) of the drying zone (7) exiting partial streams (24, 25) within the drying zone (7) are circulated. Continuous dishwasher according to claim 1, characterized in that a machine control (29) when a by in the transport direction (12) transported Sonderspülgutes (9) caused Sondebetriebszustandes the exit velocity and / or the air volume of an outlet nozzle (20) of the at least one fan exiting air flow reduced. Continuous dishwasher according to claim 1, characterized in that a machine control (29) detects the end of a Sonderspülgut (9) caused special operating condition and the exit velocity and / or the air volume at an outlet nozzle (20) of the at least one blower (7) on before the reduction set values increased.

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