EP2295627B2 - Process for treating laundry in a domestic appliance and domestic appliance, in particular domestic laundry dryer - Google Patents

Description

The invention relates to a method for treating laundry in a household appliance, in particular a household laundry dryer, and a household appliance, such as a household laundry dryer, according to the preamble of claims 1 and 9.

From the DE 34 08 136 A1 a tumble dryer is known in which by means of an external gas supply line consisting of mist and steam mixture is passed into a laundry treatment room. The known laundry dryer requires the provision of an external mist and steam generating device. The introduced into the laundry treatment room mixture of mist and steam is relatively cold. It is not very clean. Finally, drops form, which can lead to the formation of stains on the textiles.

From the DE 37 27 570 is a method for eliminating odors from textiles known. In this case, textiles received in a cabinet are subjected to dry steam and odor-binding agents. A device for generating the dry steam is also provided outside the cabinet here.

The provision of external steam generating devices is cumbersome and expensive. Such a measure is not suitable for household appliances such as household appliances.

The known household machines, in particular tumble, after the completion of the drying program, the dried laundry so long in their interior until it is removed for further processing, such as ironing, by an operator. In particular, by not immediate further processing of the extracted laundry can lose more moisture so that it contains too little moisture for further processing, especially for ironing. To compensate for this excessive loss of fluid again, it is known to spray the laundry with finely atomized water before ironing to make ironing the laundry more effective and easier. In this spraying, however, can not be reliably achieved that a uniform moistening of the laundry to be ironed is achieved.

The from the US 3,242,584 B known household tumble dryer has a rotatably mounted drum in the back to dry hot air is blown. To support the drying process, a vapor deposition device is additionally integrated, to which tap water can be supplied from outside via a fluid connection. The steaming device is metered via an inlet valve liquid supplied in a certain amount. Between the steaming device and a nozzle, which sprays the steam into the laundry drum, a pressure valve is arranged, with which the line between the steaming device and the nozzle can be released suddenly. After the liquid has been introduced into the initially cold evaporator, the valves are closed and the heating of the liquid begins. After heating, the valve is opened to the nozzle and superheated steam flows into the drum, where it causes the laundry to heat up briefly and to remove the residual moisture from the laundry. The supplied liquid vapor and the evaporated water are discharged from the tumble dryer in the exhaust air process.

The EP 1 275 767 A1 discloses a washing machine with a steaming function in which water is introduced into a washing tub up to the height of the heating rods for heating wash water. The water is heated to at least 40 ° C, so that steam rises and penetrates from the washing tub into the washing drum. During the reversing operation of the washing drum, the steam is evenly distributed to the laundry, so that wrinkles in the laundry smooth. At the same time a sterilization of the drum and the washing tub is achieved by the steam.

The post-published according to Art. 54 (3) EPC WO 2004/059070 A1 proposes a circulating air dryer with a heating element arranged in the circulating air channel. In the air circulation direction after the heating element, a shell is arranged, in which a liquid treatment agent can be filled from a storage container. The liquid evaporates and is entered with the circulating air in the laundry drum.

The object of the invention is to eliminate the disadvantages of the prior art. In particular, a method and a household appliance, such as a household tumble dryer, are given, with which a simple and effective removal of unwanted odors can be achieved and a uniform moistening of the laundry, without worsening the washing result by, for example, staining.

This object is solved by the features of claims 1 and 9. Advantageous embodiments emerge from the features of the other claims.

By the method according to the invention it is achieved that in the household appliance, a superheated steam can be made available, which can be supplied directly to the laundry directly after the production. This is advantageously made possible by the fact that the production takes place directly in the household machine, whereby extremely short transport routes for the steam are available, so that no condensation, and thus droplet formation, can take place. Heat loss of the steam is reduced by the short line lengths to a minimum, so that the steam can also be fed under control with a desired temperature of the laundry. The temperature of the steam changes on the way from Steam generators for laundry practically not, because the transport routes are extremely short. It thus eliminates the costly provision of an external steam generating device. It does not come to undesirable condensation and thus the formation of droplets in the hot steam line.

Particularly advantageously, the laundry is applied at intervals with drip-free superheated steam. The application of drip-free superheated steam is particularly effective. It is quickly achieved a removal of odors from the laundry. The formation of stains is avoided. The intermittent exposure to superheated steam causes a particularly intensive refreshing and sterilization of odor-laden laundry.

According to a further embodiment feature of the steam generator and a Wasserzuführvorrichtung are controlled such that the steam generator until a working temperature of at least 100 ° C, preferably 120 - 200 ° C, a predetermined amount of water is supplied. With this measure, it is further ensured that the hot steam generated is drip-free. The water only reaches the steam generator when it has been heated to a sufficient working temperature necessary for complete steam generation. The amount of water supplied is regulated depending on the working temperature or the electrical power consumption of the steam generator so that the water is completely evaporated. It is avoided by means of the regulation, the supply of a large amount of water. A formation of water droplets in the superheated steam is thus prevented.

The water supply to the steam generator can be done by intervalwise actuation of the pump.

According to a further particularly advantageous embodiment, the hot steam generated in the steam generator is passed through a, preferably thermally insulated, riser into a treatment chamber surrounded by the laundry drum. The provision of insulation counteracts undesired cooling of the superheated steam and thus condensation or formation of drops. Any condensate formed on the wall of the pipe flows back in the direction of the steam generator because of the slope of the pipe. It is a blowing of contaminated with drops superheated steam avoided in the treatment room.

According to a further advantageous embodiment, perfume, disinfectant, cleaning agent and / or descaling agent is added to the water or the superheated steam. This achieves a particularly effective cleaning of odor-laden laundry. If the additives mentioned above are already added to the water, it must be ensured that they evaporate without residue. Additives which do not evaporate without residue are expediently added to the superheated steam.

By the advantageous method in which the steam generator is supplied with water under control, it is advantageously achieved that only as much water is supplied as the steam generator can also convert to steam. The water is taken from a tank integrated in the household appliance. This can advantageously be a tank in which, for example, the condensate which is produced during a drying process of a household laundry drier is collected.

In an advantageous embodiment of the invention, the laundry is charged with a predetermined amount of superheated steam, thereby it is possible that the laundry can be moistened with a predetermined desired degree of moisture over the inventive method. Conveniently, the operating time of the steam generator can be determined, so that a predetermined amount of moisture reaches the laundry. In another advantageous embodiment of the invention, the laundry with hot steam is applied until it has a predetermined degree of moisture. For this purpose, the method according to the invention is further developed such that the degree of moisture of the laundry is monitored by a sensor device. In a particularly favorable embodiment of the invention, the sensor device is a sensor device which is present in a domestic appliance, for example a household laundry dryer, in order to carry out the monitoring of the residual moisture during the drying process. According to the invention, the method thus uses such a sensor unit.

In another embodiment of the invention, the laundry is acted upon with temporal interruptions with superheated steam, so that the laundry has entirely in its interior a predetermined degree of moisture. During the charging with superheated steam, according to the further inventive method, the laundry can be redeployed by rotating the drum. For this purpose, the application of hot steam can be interrupted in time, wherein advantageously the drum can be set in rotation, so that at the time of interruptions, the drum rotates and the laundry is rearranged. In a further advantageous embodiment of the invention, the influx of the superheated steam is directed into the drum, opposite to an air flowing into the drum.

In order to achieve a predetermined residual moisture, it can be provided according to the invention that the operator is able to set the moisture level of the laundry to be present after the end of the process according to the invention via an operating unit. The setting is similar to a drying process on the same control unit of the household appliance.

The other claims describe a household appliance according to the invention, in particular a household laundry dryer, in particular for carrying out the method according to the present invention. For this purpose, the household laundry dryer has an integrated steam generator and a water supply with a tank for receiving the water required for moistening the laundry. Furthermore, the apparatus according to the invention has a superheated steam line for supplying the steam from the steam generator to the laundry drum, wherein the laundry is moistened according to the method of the present invention.

In an advantageous embodiment, the device for carrying out the method according to the invention has a control that is controllable such that in the steam generator until a working temperature of at least 100 ° C, a predetermined amount of water can be supplied. This advantageously ensures that the temperature of the steam generator can never sink so far that wet steam is generated. Of particular advantage is a steam generator, which operates at a working temperature of preferably from 120 ° C to 200 ° C.

In order to always ensure a balanced advantageous ratio between supplied water and existing heat output of the steam generator, it should be provided according to the invention that the amount of water supplied in dependence on the operating temperature of the steam generator is adjustable. This ensures that its temperature can not drop so low that the water is not completely evaporated. It is particularly advantageous to thermally isolate the supply lines for the steam in order to prevent condensation. In a further favorable embodiment of the household laundry drier according to the invention, it advantageously has means for adding substances to the steam, such as, for example, fragrances, disinfectants or other ingredients described in the claims.

In a particularly advantageous embodiment of the invention, the household tumble dryer is designed as a condensation dryer, with a tank in which the condensate is collected. This is advantageously kept at the same time as long that it can be used to moisten the laundry. For this purpose, it can also be advantageously provided that, when the tank is emptied of condensate, a device is provided which prevents complete emptying, so that there is always sufficient water available for moistening laundry.

Furthermore, a household laundry drier is advantageously provided, in which a device for intermittently loading the laundry with drip-free superheated steam is provided. This allows an efficient and easy cleaning of odor-laden laundry.

For the purposes of the present invention, a "drop-free superheated steam" is understood to be a superheated steam which is free of macroscopically visible drops which can lead to the formation of stains.

The device for intermittently loading the laundry with superheated steam has a steam generator and a water supply device. The steam generator and the water supply device can be regulated by means of a control such that the steam generator until a working temperature of at least 100 ° C, preferably 120 to 200 ° C, a predetermined amount of water is supplied. By means of the control, the amount of water supplied is expediently controllable as a function of the operating temperature or the absorbed electrical power of the steam generator so that the water is completely evaporated.

The water supply device may further include a tank disposed above the steam generator. For example, the tank may be connected to a condensate tank of the household tumble drier for water supply. Alternatively, the condensate tank of the household tumble dryer can be used as a tank. The steam generator is mounted within a housing of the household laundry dryer, conveniently on a housing bottom. In this case, the steam generator can be easily supplied with water, which is supplied from an attached gravitational tank. In this case, a, preferably thermally insulated, riser connect the steam generator with a surrounding of the laundry drum treatment room. The provision of such a riser counteracts the formation of undesirable condensates. In the case of the formation of condensates, these flow back into the steam generator. Finally, a device for supplying an additive, preferably perfume, disinfectant, cleaning agent and / or descaling agent to the water or to superheated steam can be provided. Such a device may have a separate container. An embodiment of the invention will be explained in more detail with reference to the single drawing.

In the drawing, a water tank 1 is connected via a supply line 2 to a pump 3. The pump 3 is connected on the pressure side via a pressure line 4 to a steam generator 5. From the steam generator 5, a thermally insulated superheated steam line 6 leads to a treatment chamber 8 surrounded by a laundry drum 7. A pump control 9 is provided with a control circuit 10, by means of which the pump 3 can be switched on at intervals via a switching contact 11. The steam generator 5 is provided with a thermocouple 12 which is connected to the pump control 9 for measuring the temperature.

The function of the pump control 9 is the following: First, the steam generator 5 is electrically heated. The heating of the steam generator 5 can be program-controlled. The temperature prevailing in the steam generator 5 is continuously measured by means of the thermocouple 12. Once the steam generator 5 a predetermined operating temperature of, for example 140 ° C, the switching contact 11 is closed by means of the pump control circuit 10. As a result, water is injected into the steam generator 5 by means of the pump 3. Because of the preheating of the steam generator 5 ensures that the injected water completely evaporated. As soon as the temperature in the steam generator 5 drops below a predetermined minimum temperature value, the switching contact 11 is opened by means of the pump control circuit 10 and a further supply of water to the steam generator 5 is interrupted. In this way it is prevented that the steam generator 5 is supplied with water even if its temperature has fallen so far that a drip-free hot steam generation is no longer possible. The hot steam generated in the steam generator 5 passes through the, preferably designed as a riser, steam line 6 in the treatment room 8. Additives, such as fragrances, disinfectants and the like. For example, the water absorbed in the water tank 1 can be added. But it is also possible to inject such additives in the hot steam line 6 finely distributed by means of a nozzle. Due to the fine distribution of the injected additives, they are also vaporized and fed into the treatment chamber 8 together with the superheated steam.

With the proposed household tumble dryer can be cleaned in a simple and efficient way odorous laundry. In this case it is not necessary to wash the laundry. This achieves a saving of resources.

In another embodiment, it is provided that the pump control is additionally acted upon by a signal of a humidity sensor 20. For this purpose, the humidity sensor 20 is connected via signal lines 21 to the pump control 9. The mode of action of the humidity sensor 20 is the one that the pump control no longer controls the pump when the laundry in the treatment chamber 8 has the desired moisture. By means of an operating device, not shown, the operator can set the desired moisture or moisture level of the laundry, which accordingly acts on the pump control 9 via a program control (also not shown).

In one embodiment, the laundry is treated with drop-free superheated steam, preferably at intervals.

In one embodiment, the steam generator (5) and a Wasserzuführvorrichtung (1, 2, 3, 4) regulated such that the steam generator until a working temperature of at least 100 ° C, preferably 120 to 200 ° C, a predetermined amount of water is supplied.

The amount of water supplied is controlled depending on the working temperature or the absorbed electric power of the steam generator (5) so that the water is completely evaporated.

In one embodiment, the superheated steam generated in the steam generator (5) is conducted via a, preferably thermally insulated, riser (6) into a treatment space (8) surrounded by the laundry drum (7).

In one embodiment, perfume, degerminating agent, cleaning agent and / or descaling agent are added to the water or the superheated steam.

In one embodiment, the laundry is charged with hot air.

In one embodiment, the water used is the condensate that was stored in a tank during the drying process of the household tumble drier.

In one embodiment, the laundry is charged with a predetermined amount of superheated steam.

In one embodiment, the predetermined amount of water is determined by a predetermined operating time of the steam generator.

In one embodiment, the laundry is charged with hot steam until the laundry has a predetermined degree of moisture.

In one embodiment, the degree of moisture of the laundry is monitored by a sensor device. In this embodiment, optionally, the sensor device that is used in the household tumble dryer to monitor the residual moisture during drying, the sensor unit used.

In one embodiment, the laundry is acted upon with temporal interruptions with superheated steam.

In one embodiment, the laundry is redeployed during the application of superheated steam by rotating the drum.

In one embodiment, the loading of the laundry with superheated steam takes place with time interruptions. In this embodiment, the drum is optionally rotated during the interruptions.

In one embodiment, the direction of the superheated steam flowing into the drum is directed against the flow of the drying air of the household laundry drier.

In one embodiment, the operator of the household laundry dryer via an operating unit, the degree of moisture of the laundry, which should be available after completion of the process can be adjusted. In this embodiment, the setting is optionally carried out via the same operating unit as for the drying process before washed laundry.

The embodiments of the method can be combined with one another as desired.

In one embodiment of the household laundry dryer, the steam generator (5) and the water supply device (1, 2, 3, 4) by means of a control (9, 10, 11) can be controlled so that the steam generator (5) only when reaching a working temperature of at least 100 ° C, preferably 120 ° C to 200 ° C, a predetermined amount of water is supplied.

The household tumble dryer by means of the control (9, 10, 11), the amount of water supplied depending on the operating temperature or the absorbed electric power of the steam generator (5) adjustable so that the water is completely evaporated.

In one embodiment of the household laundry dryer connects a, preferably thermally insulated, riser (6) the steam generator (5) with one of the laundry drum (7) surrounded treatment chamber (8).

In one embodiment of the household laundry dryer, a device for supplying an additive, preferably perfume, disinfectant, cleaning agent and / or decalcifier, water or hot steam is provided.

In one embodiment of the household tumble dryer, the household tumble dryer is a condensation dryer and the tank (1) can be filled with the condensate of the household tumble dryer.

In one embodiment of the household laundry dryer, the container for receiving the condensate is at the same time the tank (1).

The embodiments of the household laundry dryer can be combined with each other.

LIST OF REFERENCE NUMBERS

1

water tank

2

supply line

3

pump

4

pressure line

5

steam generator

6

Hot steam line

7

washing drum

8th

treatment room

9

pump control

10

Pump control circuit

11

switching contact

12

thermocouple

20

humidity sensor

21

signal line

Claims (12)

1. Method for treating laundry in a domestic appliance, especially a domestic tumble dryer, wherein the laundry is inserted into a rotatably held washing drum (7), the laundry is subjected to super-heated steam, the super-heated steam is generated in a steam generator (5) which is integrated in the domestic appliance, a water feeding apparatus (1, 2, 3, 4) supplies the steam generator (5) with water, a super-heated steam line (6) supplies the steam from the steam generator (5) to the washing drum (7), and the steam generator (5) is supplied with water in a controlled manner, characterized in that the water feeding apparatus comprises a tank (1) integrated in the domestic appliance for withdrawing water, and the water feeding apparatus comprises a pump (3) which can be triggered by means of a feedback control unit (9, 10, 11) for supplying the steam generator (5) with water, wherein a quantity of the water supplied to the steam generator (5) is controlled depending on the working temperature or the consumed electrical power of the steam generator (5) in such a way that the water is evaporated completely.
2. Method according to Claim 1, wherein the super-heated steam line (6) is thermally insulated.
3. Method according to Claim 1 or 2, wherein the tank (1) is connected via a supply line (2) with the pump (3), and the pump (3) is connected on the pressure side via a pressure line (4) with the steam generator (5), wherein, from the steam generator (5), the preferably thermally insulated super-heated steam line (6) leads to a treatment chamber (8) which is enclosed by a washing drum (7), wherein a pump control unit (9) is provided with a feedback control circuit (10), by means of which the pump (3) can be activated in intervals via a switching contact (11), and wherein the steam generator (5) is provided with a thermoelement (12) which is connected with the pump control unit (9) for measuring the temperature.
4. Method according to one of the preceding claims, wherein the steam generator (5) and the water feeding apparatus (1, 2, 3, 4) are controlled in such a way that a predetermined quantity of water is supplied to the steam generator only when reaching a working temperature of at least 100°C, preferably 120 to 200°C.
5. Method according to one or several of the preceding claims, characterized in that the laundry is subjected to a predetermined quantity of super-heated steam, wherein especially the predetermined quantity of steam is determined by a predetermined operating time of the steam generator (5).
6. Method according to one or several of the preceding claims, characterized in that the laundry is subjected to super-heated steam with temporal interruptions.
7. Method according to one or several of the preceding claims, characterized in that the laundry is re-shifted by rotation of the drum (7) while being subjected to super-heated steam.
8. Method according to one or several of the preceding claims, characterized in that the inflow of the super-heated steam is directed in the opposite direction to drying air flowing into the drum (7).
9. Domestic appliance, especially a domestic tumble dryer, comprising a rotatably held washing drum (7) for laundry, wherein the domestic appliance comprises an integrated steam generator (5), a water feeding apparatus (1, 2, 3, 4) and a super-heated steam line (6) for the supply of steam from the steam generator (5) to the washing drum (7), characterized in that the water feeding apparatus comprises the following: a pump (3) which can be triggered by means of a feedback control unit (9, 10, 11) for supplying the steam generator (5) with water, and a tank (1) integrated in the domestic appliance for accommodating water for supplying the steam generator (5), wherein the quantity of the water supplied can be controlled by means of the feedback control unit (9, 10, 11) depending on the working temperature or the consumed electrical power of the steam generator (5) in such a way that the water is evaporated completely.
10. Domestic appliance according to Claim 9, wherein the tank (1) is connected via a supply line (2) with a pump (3) and the pump is connected on the pressure side via a pressure line (4) with the steam generator (5), wherein, from the steam generator (5), the preferably thermally insulated super-heated steam line (6) leads to a treatment chamber (8) which is enclosed by a washing drum (7), wherein a pump control unit (9) is provided with a feedback control circuit (10), by means of which the pump (3) can be activated in intervals via a switching contact (11), and wherein the steam generator (5) is provided with a thermoelement (12) which is connected with the pump control unit (9) for measuring the temperature.
11. Domestic appliance according to Claim 9 or 10, wherein the preferably thermally insulated super-heated steam line (6) connects the steam generator (5) with a treatment chamber (8) enclosed by the washing drum (7).
12. Domestic appliance according to one of Claims 9 to 11, wherein the steam generator (5) and the water feeding apparatus (1, 2, 3, 4) are controllable by means of a feedback control unit (9, 10, 11) in such a way that a predetermined quantity of water is supplied to the steam generator (5) only when reaching a working temperature of at least 100°C, preferably 120°C to 200°C.

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