DE102011084408B4 - Steam generating domestic appliance with wet steam function - Google Patents

Abstract

Steam-generating domestic appliance (1) with a heatable pressurized water container (5), a first conveyor for water from the pressurized water container (5), a first line (8), which is upstream of the first conveyor (6) to the first conveyor (6) water from the pressurized water tank (5) to be supplied, wherein the pressurized water container (5) is equipped with a water level control to set in the pressurized water tank (5) during operation of the household appliance (1) a water level (10), wherein the household appliance (1) has a second line (9), to remove water from the pressurized water container (5), characterized in that the outputs of the first conveyor (6) and a second conveyor (7), which is connected upstream of the second line (9), are brought together the second line (9) in the removal of water, the water always only above the water level (10) removes and that during operation of the household appliance (1) the first line (8) always removes the water at the same time both above and below the water level (10) in the removal of water.

Description

The invention relates to a steam-generating domestic appliance with a heatable pressurized water container, a first conveyor for water from the pressurized water tank, a first line which is connected upstream of the first conveyor to supply the first conveyor water from the pressurized water tank, the pressurized water tank is equipped with a water level control, to set a water level in the pressurized water container during operation of the household appliance, wherein the household appliance has a second line to remove water.

It is common practice to use steam generating domestic appliances in the form of irons for smoothing textiles or similar fabrics in the private or commercial sector. When using an iron, a flat, smooth surface, the soleplate, heated and placed on the sheet to be smoothed. By pressure and movement of the iron relative to the fabric, wrinkles are removed from the fabric, often accompanied by a simultaneous supply of steam. In this case, the temperature of the soleplate to achieve a good smoothness effect is usually chosen so that the fabric is just not damaged in a short-term contact with the soleplate. Another steam-generating household appliance, for example, a steam cleaner, is discharged in the wet steam through a aufzusetzende on the surface to be cleaned steam nozzle. Other steam-generating household appliances are also devices for producing coffee, milk foam or for cleaning curtains.

A device for generating steam for domestic use is disclosed in the publication DE 34 10 247 A1 known. The device described therein consists of a provided with an electrical resistance for heating and evaporation of water heating tank with a water tank separated from the heating tank. A pump is connected between the heating tank on one side and the tank on the other side. A minimum water level signal transmitter in the heating tank activates the pump at a previously set minimum water level and a maximum pressure signal transmitter in the heating tank switches off the pump at a previously set maximum steam pressure. This may be disadvantageous in that the superheated steam produced in this embodiment has a low moisture content, but for effective ironing a higher moisture content of the steam is desired.

This problem is the subject of the disclosure DE 196 14 511 C1 , It relates to a steam ironing station, which has a water tank, a first activatable via a steam switch feed pump and a steam generator and heating, wherein via a first water line water from the water tank by means of the first feed pump is fed into the steam generator and the steam generated in the steam generator via a steam line is passed into the iron and a second water line ("bypass line") is conveyed via the water with a second feed pump into the steam line. By this arrangement, a higher humidity of the steam is achieved. The steam ironing station is further equipped with an electronic control, which is activated by an operating device in the form of a switch disposed on the handle of the iron switch and controls the two feed pumps. A disadvantage of this arrangement may be the expenditure on equipment that results from the use of two pumps.

From practice, another steam ironing station is known, which selectively promotes water from a water reservoir in the steam generator or in the bypass line via a 3/2-way valve. Here only one pump is provided. This may have the disadvantage that when filling the steam generator from the water tank can not be promoted water into the steam line simultaneously.

The publication US2010 / 0011629 A1 relates to a device that can be used to produce superheated water. The device consists of a water tank and a heating element. During use, the water is usually heated to 120 ° C to 140 ° C. The document also relates to a household appliance containing this device for the production of superheated water. From the water tank, water or steam can be removed by means of a hose or pipe. A valve controlled by the user makes it possible to remove water or steam from the water tank when opening it and to provide it, for example, in the form of a steam jet. In the water tank there may be an outflow, which is at least partially below the water level and thus can partially remove steam and water in part from the tank. However, no means are disclosed which ensure that a mixture of steam and water is always withdrawn.

From the European patent EP 1 311 786 B1 discloses a household appliance for generating steam, comprising a boiler with a heating source for evaporating water and a control means with a setting means for adjusting the vapor pressure in the boiler. Further, a steam supply means is provided which cooperates with the adjusting means for adjusting the pressure in the boiler so that the heating source in response to the open and closed State of the steam supply means is switched on and off. The boiler is filled by means of a pump from a reservoir with water. The pump is controlled by a temperature sensor, which, based on the measured temperature, allows a conclusion as to whether water must be topped up.

Both the patent US 2,886,689 A as well as the patent US 2,785,271 A describe a steam generator having a boiler into which an outlet pipe protrudes from above. The outlet pipe has a hole through which steam from the boiler can flow into the outlet pipe. In addition, the outlet pipe receives a hole through which water from the boiler can flow into the outlet pipe.

The invention is based on the object to provide an improved steam-generating household appliance with a durable pressurized water tank, a first conveyor for water from the pressurized water tank and a first, the conveyor upstream line to supply the conveyor water from the pressurized water tank. In particular, it should be possible with the invention to produce a wet steam. The steam-generating household appliance should be simple and inexpensive in construction and reliable in operation.

The solution of the object is achieved by a steam-generating household appliance with the features of claim 1. The invention can be advantageously produce unusually simple means a water-enriched steam. In the heatable pressurized water tank, the water is always partly in the liquid and partly in the gaseous state, ie as water vapor. The water level separates the steam above it from the water below it. Due to the fact that, during operation of the domestic appliance, the first line always removes the water both above and below the level of the water during the removal of water, steam and liquid water can always be taken out at the same time. The two fractions can subsequently be mixed to a water-enriched vapor.

For the purposes of the present invention, "water" may denote both vaporous water, ie water vapor, and liquid water. A water level control is a device that ensures by appropriate measures that during operation of the household appliance, the height of the water level in the pressure water tank is always within a specified range between a minimum filling level and a maximum filling level of the pressurized water tank. The fact that a water level is adjusted by the water level control in the pressurized water tank, it can be ensured that the line water can always remove both above and below the water level at the same time.

The conveyor is or usually comprises a pump and / or a switchable valve, preferably an electrically switchable valve, for. B. a solenoid valve. The first line opens directly or indirectly into the conveyor to supply the water from the pressurized water tank.

In addition to the first performance, the steam-generating household appliance still has one or more further lines, which can remove water from the pressurized water container above the water level. The second power does not flow into the first line or into the first conveyor; Rather, a second conveyor for water from the pressurized water tank is provided, which is connected upstream of the second line and which supplies the second line of water from the pressurized water tank.

Advantageous embodiments and developments, which can be used individually or in combination with each other, are the subject of the dependent claims.

Preferably, the first conduit is arranged and designed so that the water is passed to the first conveyor after removal as wet steam. In a wet steam, the liquid water is distributed in the form of fine drops of water in the water vapor. In other words, liquid water and water vapor are mixed in the first line to a wet steam.

In a preferred embodiment of the invention, the first line for water removal is equipped with a filter. A filter in the sense of the present invention has a plurality of openings, which always lie partly above and partly below the water level in the fluctuation range of the regulated water level. Thus, liquid water can be removed through the opening (s) below the water level and water vapor can be removed through the opening (s) located above the water level. Preferably, at least a portion of the openings, more preferably all openings of the filter are designed so that water vapor can pass through them. Preferably, at least a portion of the openings, more preferably all openings of the filter are designed so that at least liquid water can pass through them. A preferred filter has at least 8, more preferably at least 20 holes. Preferred holes have a diameter of less than 2 mm, more preferably less than 1 mm.

In an alternative embodiment of the invention, the first line for water removal only a slot that is always partially above and partly below the water level. Thus, both liquid water and water vapor can always be absorbed by the same hole. Of course, a filter may have one or more such slots.

The filter may also have one or more branches, as long as all branches run together in front of the conveyor or open together into the conveyor. As a result, a part of the openings of the filter may be arranged on one branch of the filter and another on another branch. The filter or a branch of the filter can assume any cross-section. In a preferred embodiment, the filter has a circular, oval or rectangular cross-section.

The preferred filter is a portion of the first conduit provided with a plurality of openings. Preferably, at least one of the openings is arranged on an end face of one end of the line section. Alternatively or additionally, at least one of the openings is arranged in a jacket of the line section. The frontal opening (s) is / are preferably below the water level during operation of the steam-generating household appliance, d. H. it is / are preferably intended for removal of liquid water. An end opening is preferably formed by an open end of the line section. The shell opening (s) or at least a part of the shell opening is / are preferably always above the water level during operation of the steam generating domestic appliance, d. H. it is / are preferably intended for the removal of water vapor.

Of course, embodiments of the invention are conceivable in which the filter at least not only through holes in the line section but at least partially by a arranged on the line grid or fabric, knitted or knitted fabric, a perforated flexible membrane, a flow material and / or an open-cell Foam material is formed. It is important, however, in turn, that always part of the openings of the respective material in the operation of the household appliance water vapor above the water level and another part can remove liquid water below the water level.

In a preferred embodiment of the invention, the filter acts as a scale filter or dirt filter. This advantageously achieves that lime and / or dirt can be kept away from the first line in order to improve the service life and reliability of the device.

According to the invention, the second line always removes the water only above the water level when removing water, so it is always taken only water vapor. Of course, an alternative, unclaimed solution is conceivable in which the second line always removes the water below the water level when removing water, so always liquid water is removed. Finally, a, also not claimed, embodiment is conceivable in which, during operation of the household appliance, the second line always removes the water both above and below the water level at the time of water extraction. In this case, the second line is preferably arranged and designed so that the water is passed to the conveyor after removal as wet steam. The preferred second conduit, like the preferred first conduit, is provided with a filter, which is particularly preferably a portion of the second conduit provided with a plurality of openings. Preferably, one or more of the openings of the filter are located on an end face of one end of the second conduit section. Additionally or alternatively, one or more openings of the second filter are located in a jacket of the second line section.

The preferred home steam generating appliance may be operated in several different modes, such as with different mixtures of water and steam from different lines. The inventive multiple modes can advantageously in a, z. B. the second mode of operation, a different mixture of steam and liquid water are provided as in another, z. B. the first operating mode. In the case where the steam generating domestic appliance is a steam ironing station, the modes for treating various fabrics and textiles may be provided. In the case where the steam-generating domestic appliance is a steam cleaner, the various modes may be provided for various types of cleaning, such as cleaning curtains, cleaning various surfaces or self-cleaning. In a particularly preferred embodiment of the invention, the steam-generating domestic appliance can be operated in a first operating mode in which steam can be obtained exclusively from the second line. In addition, the household appliance in this embodiment of the invention can be switched to a second operating mode, in which additionally or exclusively steam from the first line can be obtained.

The switching between the first and second modes may be performed by a user, e.g. Example by means of a switch, or by a control device, the latter z. B. time or sensor controlled. At a time control that can Household appliance z. B. at fixed intervals temporarily be switched from the first to the second operating mode, in a sensor control could, for. B. depending on the temperature of a soleplate of a steam iron or steam ironing station trained domestic appliance between the modes are selected.

The preferred domestic appliance has an operating element for a steam pulse, which temporarily switches from the first operating mode to the second operating mode during operation and then switches back into the first operating mode. As a result, z. B. in the first mode of operation substantially continuously dry superheated steam above the water level are removed through the second line and temporarily switched when operating the control element for a steam burst in the second operating mode in which the household appliance by the second line moist steam from the pressurized water tank for example, to remove stubborn wrinkles on a textile or impurities that are difficult to remove on a surface. The preferred control is a push button.

Preferably, upon actuation of the operating element for the duration of the operation of the first operating mode is switched to the second operating mode and switched back to the first operating mode with the termination of the operation. Alternatively or additionally, it is possible to switch from the beginning of the actuation for a predetermined time to the second operating mode and to switch back to the first operating mode after the predetermined time has elapsed.

The household appliance is preferably configured such that it always obtains steam from the second line at least for a short time after drawing steam from the first line. As a result, it can be advantageously prevented that liquid water remains in the connection line.

The preferred pressurized water container has a heating element for heating the pressurized water container and a sensor for controlling the heating element. The sensor preferably measures a property of the vapor in the pressurized water container, e.g. B. the vapor pressure or the steam temperature. This can help to ensure in the pressurized water tank a constant within the required limits pressure.

The preferred water level control includes a water supply for supplying water into the vapor pressure vessel. The preferred water level control also includes a level sensor for measuring the height of the water level and a controller for controlling the water supply in response to the signal of the level sensor. A suitable water level control is z. B. from the patent EP 1 311 786 B1 known. The preferred level sensor is a temperature sensor. It is exploited that the wall temperature of the pressurized water container in the vicinity of the heating element is lower when there is water, as in the absence of water, because the water can cool the wall. An increase in the temperature measured by the temperature sensor to a first temperature limit value can thus be interpreted as an indication of the achievement of the minimum fill level. A drop in temperature to a second temperature limit can be considered as reaching the maximum fill level. In this case, the second temperature limit value is preferably lower than the first temperature limit value. Typically, the two limits are between 1 and 5 ° C (degrees Celsius) apart, z. By 2 ° C. The preferred temperature limits are above 110 ° C, the first temperature limit can be z. B. at 155 ° C and the second at 123 ° C. Due to the distance between the two limit values, a hysteresis is achieved in the fill level sensor in order to avoid fluttering of the fill level sensor signal.

The preferred water supply is an electrically driven pump or an electrically actuated valve, for. B. a solenoid valve. The preferred control device comprises a relay or a semiconductor switch for driving the conveyor. Preferably, the steam-generating domestic appliance also comprises a water storage chamber which is connected via the steam supply to the vapor pressure vessel, so that the water supply can supply water to the vapor pressure vessel from the water reservoir. Usually, the water supply, so z. As the pump or valve, connected by line pieces with the water reservoir on the one hand and the vapor pressure vessel on the other.

The preferred steam-generating household appliance is designed as a steam ironing station. The water (as water vapor, liquid water or mixture thereof) after passing through the conveyor (s) is fed to an iron of the steam ironing station. The control element for the steam pulse is preferably arranged on a handle of the iron of the steam ironing station. Additionally or alternatively, the steam-generating domestic appliance can also be designed for cleaning curtains, for cleaning surfaces, for producing coffee or milk foam or the like.

Further advantageous embodiments are described below with reference to an embodiment shown in the drawings.

They show schematically:

1 an inventive steam-generating household appliance in the form of an ironing station with steam generator and iron; and

2 a schematic representation of the pressurized water tank with the first and the second line.

In the following description of a preferred embodiment of the present invention, like reference characters designate the same or similar components.

The embodiment will be described below with reference to the 1 and 2 explained. It is in 1 an ironing station 1 shown for steam ironing an ironing board, which is a steam generator 2 and an iron 3 having. The iron 3 is via a connection cable 4 through which from the steam generator 2 steam generated in the iron 3 is directed, with the steam generator 2 connected. The steam generator 2 includes a pressurized water tank 5 , a first 6 and a second electrically controllable solenoid valve 7 as first and second conveyor for water from the pressurized water tank 5 and a first 8th and second line 9 that the first 6 and second conveyors 7 are respectively connected upstream to their associated solenoid valve 6 . 7 Water from pressurized water tank 5 supply.

In the pressurized water tank 5 the water is above a water level 10 as water vapor and below the water level 10 as liquid water. A section of the first pipe 8th reaches below the water level 10 in the pressurized water tank 5 into it. As can be better seen in Figure two, the jacket of this first line 8th with numerous openings 11 equipped, both above and below the water level 10 , This can be the first line 8th during operation of the household appliance 1 When removing water, the water is always at the same time both above and below the water level 10 remove, ie it is simultaneously withdrawn liquid and gaseous water. The end 12 the first line 8th is closed, so that not too much water is removed. Through the holes and the closed end 12 It also ensures that dust or lime particles are not in the first line and from there to the iron 3 reach. Liquid and gaseous water mix in the first line 8th on the way to the first solenoid valve 6 and form a wet steam. The second line 9 just enough above the water level 10 in the water vapor in the pressure water tank 5 in and therefore only water vapor to the solenoid valve 7 promote.

The outputs of the first 6 and the second solenoid valve 7 are merged and over a connecting line 4 with the steam iron 3 connected. Consequently, that will be over the first one 8th or the second line 9 withdrawn water when the associated solenoid valve 6 . 7 is open, via the connecting cable 4 the iron 3 fed. Are both solenoid valves 6 . 7 Open, be over the first line 8th removed wet steam and the over the second line 9 removed dry steam in the connecting line 4 mixed and so the iron 3 fed.

The ironing station 1 also has an electrical heating element 13 for heating the pressurized water tank 5 and a pressure sensor 14 for controlling the heating element 13 on. The pressure sensor 14 controls the heating element 13 via an electronic control circuit, not shown, in such a way that the heating element 13 turned on when falling below a predetermined minimum pressure and off when exceeding a prescribed maximum pressure. This has the purpose of a substantially constant vapor pressure in the pressurized water tank 5 to make sure. Especially when ironing a constant vapor pressure is of particular importance to achieve a uniform ironing result.

If about the first 6 and / or second valve 7 Water to the iron 3 is handed over to the first 8th and / or the second line 9 Water from the vapor pressure vessel 5 taken. At the latest, when the water level in the vapor pressure vessel 5 reaches a minimum filling level, water must be refilled. For this serves a water level control of the ironing station. The water level control ensures that when operating the home appliance 1 the height of the water level 10 in the pressure water tank 5 always in a fixed range between a minimum and a maximum filling level of the pressurized water tank 5 lies.

This includes the ironing station 1 a water storage 15 , which has a water supply in the form of a pump 16 with the vapor pressure vessel 5 fluid-connected, so that the water supply 16 the vapor pressure vessel 5 Water from the water reservoir 15 can supply. Furthermore, a level sensor for measuring the height of the water level 10 intended. The level sensor is a temperature sensor 17 that measures the wall temperature near a heating element 13 of the vapor pressure vessel 5 measures. For level measurement with the temperature sensor 17 is exploited that the wall temperature of the pressurized water tank 5 near the heating element 13 is lower, if there is water there, than in the absence of water. When the minimum filling level is reached, the heating element is 13 not covered by water for a short time. A control device 18 to control the water supply evaluates the signal of the temperature sensor 17 off and controls the pump 16 accordingly.

The first 6 and the second solenoid valve 7 can at the steam ironing station 1 independently by first 20 and second key switch 19 and a valve control device 21 be operated. A first switch 20 actuates the first valve 6 to create a wet steam blast. This is done by pressing the first pushbutton 20 located on the handle of the iron, the first valve 6 controlled by the valve control 21 , for a fixed duration of z. B. one second, upon renewed actuation of the first key switch 20 becomes the first valve 6 reopened for another shot of steam. Each after closing the first valve 6 is also controlled by the valve control device 21 , valve for a short time 7 opened to prevent liquid water in the connecting cable 4 remains. Also, the first valve 6 be opened at regular intervals to produce a continuous or pulsating vapor. Also, such a series of pulses can be initiated by pressing the first key switch and terminated by pressing again. The duration of the pulsating steam may also be limited to a predetermined duration. A second limited series of pulses may be initiated by actuating the first pushbutton, e.g. B. by repeatedly pressing in quick succession, similar to a double-click in a computer mouse.

The second valve 7 is the user via the second, also on the handle of the iron arranged push-button 19 actuated. Actuation of the switch is controlled by the valve control 21 , the second valve 7 open continuously or at regular intervals to produce a continuous or pulsating vapor. By pressing the second push-button again 19 This continuous or pulsating steam can be switched off again. The duration of the pulsating steam may also be limited to a predetermined duration. A second limited series of pulses may be initiated by actuating the second key switch, e.g. B. by repeatedly pressing in quick succession, similar to a double-click in a computer mouse.

With the invention can advantageously with simple structural means in the ironing station 1 a wet steam for steam shocks are produced. It can also be avoided that dust or lime particles in the first pipe 8th and from there via the connecting line 4 to the iron 3 reach.

The features disclosed in the foregoing description, the claims and the drawings may be of importance both individually and in any combination for the realization of the invention in its various forms.

LIST OF REFERENCE NUMBERS

1

ironing station

2

steam generator

3

Iron

4

connecting cable

5

Pressurized water tank

6

First solenoid valve

7

Second solenoid valve

8th

First line

9

Second line

10

water level

11

Openings in the first pipe

12

End of the first line

13

heating element

14

pressure sensor

15

water-tank

16

water supply

17

temperature sensor

18

control device

19

Second push-button

20

First pushbutton

21

valve control

Claims (12)

Steam generating domestic appliance ( 1 ) with a heatable pressurized water container ( 5 ), a first conveyor for water from the pressurized water tank ( 5 ), a first line ( 8th ), the first conveyor ( 6 ) is connected upstream of the first conveyor ( 6 ) Water from the pressurized water container ( 5 ), whereby the pressurized water container ( 5 ) is equipped with a water level control in order to 5 ) in the operation of the household appliance ( 1 ) a water level ( 10 ), the household appliance ( 1 ) a second line ( 9 ) to remove water from the pressurized water tank ( 5 ), characterized in that the outputs of the first conveyor ( 6 ) and a second conveyor ( 7 ), the second line ( 9 ), are merged, that the second line ( 9 ) when removing water, the water is always only above the water level ( 10 ) and that during operation of the household appliance ( 1 ) the first line ( 8th ) at the time of water extraction, the water is always at the same time both above and below the water level ( 10 ) removes. Steam generating domestic appliance ( 1 ) according to claim 1, characterized in that the first line ( 8th ) is arranged and designed so that the water after removal as wet steam to the first conveyor ( 6 ). Steam generating domestic appliance ( 1 ) according to one of the preceding claims, characterized in that the first line ( 8th ) is equipped with a filter for water extraction. Steam generating domestic appliance ( 1 ) according to claim 3, characterized in that the filter is one having a plurality of openings ( 11 ) section of the first line ( 8th ). Steam generating domestic appliance ( 1 ) according to claim 4, characterized in that at least one of the openings ( 11 ) on an end face of a portion of the end of the first conduit ( 12 ) is arranged. Steam generating domestic appliance ( 1 ) according to claim 4 or 5, characterized in that at least one of the openings ( 11 ) is arranged in a jacket of the line section. Steam generating domestic appliance ( 1 ) according to one of the preceding claims, characterized in that the domestic appliance ( 1 ) is operable in a first mode of operation, wherein from the second line ( 9 ) Steam, and the household appliance ( 1 ) is switchable to a second operating mode, in which additionally or exclusively steam from the first line ( 8th ) can be obtained. Steam generating domestic appliance ( 1 ) according to claim 7, characterized in that the household appliance ( 1 ) an operating element ( 19 ) for a steam blast, which temporarily switches on actuation from the first operating mode to the second operating mode and then switches back to the first operating mode. Steam generating domestic appliance ( 1 ) according to one of the preceding claims, characterized in that the domestic appliance ( 1 ) is configured in such a way that it always after the withdrawal of steam from the first line ( 8th ) at least for a short time steam from the second line ( 9 ). Steam generating domestic appliance ( 1 ) according to one of the preceding claims, characterized in that the water level control a water supply ( 16 ) for supplying water into the vapor pressure vessel ( 5 ), a level sensor ( 17 ) for measuring the height of the water level ( 10 ) and a control device ( 18 ) for controlling the water supply ( 16 ) in response to a signal from the level sensor ( 17 ). Steam generating domestic appliance ( 1 ) according to one of the preceding claims, characterized in that the pressurized water container ( 5 ) a heating element ( 13 ) for heating the pressurized water container ( 5 ) and a sensor ( 14 ) for controlling the heating element ( 17 ) having. Steam generating domestic appliance ( 1 ) according to one of the preceding claims, characterized in that the domestic appliance ( 1 ) is designed as a steam ironing station.

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