EP3098345A1 - Steam iron and method for operating a steam iron - Google Patents

Abstract

A steam iron (1) is described in which a presettable temperature preset depending on the presence of a steam request signal is changed by a controller by controlling a sole temperature other than the preset temperature preset by the controller (26). In particular, in a lower temperature preset range can thus be ensured that by increasing the sole temperature of the iron steam generation can be achieved without droplet formation. The process according to the invention describes how steam generation without droplet formation is possible.

Description

The invention relates to a steam iron with a water storage tank, a heater of a steam chamber and a pump for pumping lime water into the steam chamber according to the preamble of patent claim 1 and a method of operating a steam iron with a built-in sole steam chamber, in which it is determined whether a steam request is present according to the preamble of claim 8.

State of the art

A steam iron of this type is for example from the German patent application DE 10 2014 204 2079 A1 known. There, a steam iron is disclosed in which a pump from a water tank delivers lime water into a steam chamber to produce steam for the steam iron. The disclosed there steam iron has a position sensor to determine layers of the steam iron, wherein in a different from a horizontal working position alternative position, the pump is deactivated.

Furthermore, the commercially available steam iron called the Bosch TDi90 has a temperature-dependent pump control which prevents droplet formation during steam generation by reliably preventing, via a water flow control as a function of temperature, more water being conveyed to the bottom to produce steam to produce, as can be evaporated there. A particular challenge in this context is a lower temperature setting of the steam iron. Usually, points are applied to a rotary selector, with the choice of which roughly a temperature range can be specified. The steam iron works in particular as a function of the temperature sensitivity of textiles in different temperature ranges, which are usually specified on a rotary knob. Often defined settings of one, two, or three points are preselected. The low temperature range with a setting of one point is for example between 70 ° and 120 ° C. Because water in usually vaporized at normal air pressure only at 100 ° C, it may come to droplet formation in this low temperature range. Therefore, usually with market standard steam irons a steam delivery, or a shot of steam at this setting is prevented by the pump is turned off.

The problem underlying the invention

The invention has for its object to provide an improved steam iron and a method for operating a steam iron, wherein in particular in a lower temperature range, a droplet-free steam delivery is ensured.

Generally, with steam iron, reliable and convenient handling is desirable. It is particularly disadvantageous if, during steam ironing, droplets are applied to the fabric via the iron. Because this can have the consequence that these droplets must then be dried by prolonged ironing, which significantly increases the time required for the ironing of garments and the quality impression of the steam iron is reduced. In addition, a technically simple structure of the steam iron is desirable because it reduces the manufacturing cost and maintenance, while increasing the reliability because of the reduced number of parts.

The invention is therefore in particular the object of providing an improved steam iron and a method for operating a steam iron, wherein in a lower temperature preselection range for the operation of the steam iron steam delivery at reduced or even without any droplet formation is possible.

Inventive solution

To achieve the object, the present invention teaches a steam iron according to the features of claim 1 and a method for operating a steam iron according to the features of claim 8.

According to the invention is in a steam iron with a sole heating and a steam chamber located there temperature-dependent promoted with a pump cold water to produce steam from it. The amount of water depends on the sole temperature and / or on a sole temperature preset setting, preferably on both. The sole temperature preset setting may be user settable, factory preset, or adjusted by an adjuster, e.g. given on the basis of measured data. Cold water in the sense of the present invention is liquid water in contrast to the water vapor generated in the steam chamber.

According to the invention, the temperature preset setting is compared in a comparison device with a present steam request signal, that is set in dependence on the presence of the steam request signal and the temperature preset setting a temperature deviating from the temperature preset setting. In this way, in particular, it is ensured that, depending on a lower temperature preselection, in particular with a setting of one point and at temperature ranges between 70 ° and 120 ° C., a higher temperature can be set in this lower temperature range in the case of a steam request, for example a temperature between 120 ° C and 180 ° C, preferably between 120 ° C and 145 ° C, for example 130 ° C. By setting a higher temperature can ensure that even in a lower temperature range no droplets in the steam release form that steam quickly is available and an optimal ironing result can be achieved. Damage to fine and delicate tissue by such a temperature increase can be reliably avoided by the fact that the steam is substantially 100 ° C hot and thus its temperature is within the preselected temperature range. At the same time, the fabric is moistened quickly. With the invention it can be achieved that, in the subsequent absence of a steam request, the temperature is regulated again to a lower value, typically as a function of the temperature preset setting. Thus, it allows the solution according to the invention, the temperature of the sole by turning on the heater at a steam demand and by increasing the set temperature to achieve a better ironing result with improved quality impression, which can be reliably prevented that even delicate tissue can be damaged because not at existing steam request signal only the preselected temperature range is regulated. According to the invention it is determined whether a steam demand is present and depending on the preset temperature, a different sole temperature is set at the present steam demand than the preset temperature. This makes it possible to prevent droplet formation even at a lower preset temperature. In particular, at a lower temperature preselection, a higher than the preselected temperature is set in order to reliably evaporate water in the sole. Specifically, damage to sensitive tissues can be avoided because the vaporized water at normal pressure has about 100 ° C and thus does not set in the tissue due to its rapid humidification, a higher temperature than one example, at one point as area code as defined by law. In the absence of a steam request, the preselected temperature can be promptly regulated again.

Structure and development of the solution according to the invention

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

In one embodiment of the invention, the controller is configured to increase the temperature, that is, to set a higher sole temperature due to the presence of a steam request signal than if this signal were absent. In this way, it is ensured by an increased amount of heat that water pumped by the pump is reliably converted into steam, the steam temperature is about 100 ° C even during evaporation and thus the tissue to be treated is reliably moistened and treated gently.

This embodiment of the invention may be further developed such that an elevated temperature is set by the controller in a lower temperature preselection range when the steam is requested. Thus, it is reliably ensured in an area in which vapor droplets can easily form that all the cold water pumped by the pump can be vaporized, because an increased sole temperature provides a higher quantity of heat for the evaporation of the water. For the purposes of the present invention, a lower temperature preselection range is one or more temperature presetting settings (for example, "one point") that are lower than one or more other temperature preset settings (for example, "two dots" and "three dots") is or will be from a total of possible temperature preset settings.

In a further development of the steam iron, a sole temperature sensor is present, which is connected to the controller. Such a configuration ensures that, depending on the sole temperature, the correct amount of water can be delivered through the pump, which does not actually cause droplet formation and can reliably monitor whether the sole has sufficient temperature to start pumping water. This has the particular advantage that when a steam demand in a lower temperature range drops of water and a wetting of the fabric can be reliably prevented.

The invention may be further developed such that there is a separate instant steam request switch on the steam iron connected to the controller. In this way, a steam request signal can be generated manually with the instant steam request switch, within the controller then immediately the heater can be turned on, and optionally a different temperature can be set depending on the temperature preset setting. The preferred instant steam demand switch also controls the pump for conveying the cold water into the steam chamber.

This embodiment of the invention may be further developed such that the controller is adapted to immediately turn on the heater in response to a present steam request signal to rapidly provide the heat energy required for steam generation. Here it can be assumed in particular that by applying water to the soleplate whose temperature decreases and thus a possible short-term increase in temperature until the water is pumped through the pump on the sole is harmless.

The preferred steam demand signal is identical to or coincident with the beginning of the delivery of cold water into the steam chamber. More preferably, the steam request signal is identical or coincident with a signal to activate the pump or is or coincides with activating the pump. In this way it is advantageously achievable that the sole temperature substantially simultaneously with the generation of steam is raised. Conceivable, however, embodiments of the invention, in which the steam generation signal is generated by a sensor which detects the presence of cold water in the steam chamber or its supply to the steam chamber, such as a temperature sensor which measures a temperature drop induced by cold water, for example in the wall the steam chamber or inside the steam chamber.

In one embodiment of the invention, the cold water is present in an irons integrated water reservoir for the cold water, that is, the water reservoir is located in the same housing to which the sole of the steam iron is attached. In an alternative embodiment of the invention, the steam iron is equipped with an external water reservoir, that is, the cold water water reservoir is not in the housing to which the soleplate of the steam iron is attached. Preferably, in the latter embodiment of the invention, the reservoir is connected by means of a water conduit, for example a water hose, to a component of the steam iron comprising the soleplate of the steam iron.

The invention may be further developed such that the controller is adapted to generate the steam demand signal. In this way it is achieved that in automatic ironing programs with, for example, interval-like steam delivery by pump activation regardless of the preset temperature reliably droplet formation in ironing operation can be prevented.

The method according to the invention can be further developed such that an elevated temperature is set depending on the preselected temperature. In this way, it can be achieved, in particular, that an elevated temperature is set in a preselected lower temperature range and thus an increased temperature is available for the evaporation of the water in the sole. Thus reliable prevents droplet formation and the water is completely vaporized.

In a further development of the method according to the invention, the sole heating is activated immediately in the presence of a steam demand. In this way, it is achieved that the soleplate is quickly brought to the set temperature to be set and no unnecessary delay occurs during steam generation.

Brief description of the drawings

• Figur 1 einen Längsschnitt durch ein Ausführungsbeispiel eines erfindungsgemäßen Dampfbügeleisens;
• Figur 2 ein Beispiel einer temperaturabhängigen Wasserförderung durch eine Pumpe in einem oberen Temperaturvorwahlbereich;
• Figur 3 ein Beispiel einer temperaturabhängigen Wasserförderung durch eine Pumpe in einem unteren Temperaturvorwahlbereich; und
• Figur 4 ein Beispiel eines Temperaturverlaufs gemäß einem erfindungsgemäßen Verfahren zum Betrieb eines Dampfbügeleisens.

The invention is explained below with reference to schematic drawings and exemplary embodiments. Show it:

• FIG. 1 a longitudinal section through an embodiment of a steam iron according to the invention;
• FIG. 2 an example of a temperature-dependent water delivery by a pump in an upper temperature preselection range;
• FIG. 3 an example of a temperature-dependent water delivery by a pump in a lower temperature preset range; and
• FIG. 4 an example of a temperature profile according to a method according to the invention for operating a steam iron.

As FIG. 1 shows a household steam iron 1 in longitudinal section of various relevant for the heating and the steam supply and their control components that are clearly visible. The steam iron 1 has a housing 2 with a handle 4 and a sole 6. The iron is shown here in a horizontal operating position. The sole 6 is heated by means of a heater 10 and has not shown outlet holes for discharging steam. The housing 2 of the steam iron preferably contains the controller 26 for carrying out relevant functions of the steam iron such as the control of steam generation, heating, and the evaluation of various sensor signals and a temperature setting. For example, the controller may include a memory in which ironing programs are stored. Hereby, a predetermined amount of steam can be dispensed at intervals in order to achieve a desired ironing result depending on a fabric and an ironing temperature.

In the housing, for example, a steam chamber 8 and a sole heater 10 is disposed within the sole. For the provision of cold water for steam generation, the steam iron on a water reservoir 12, which is connected for example via a line 14 to a pump 16 and then in turn to the steam chamber 8. As will be explained further below, depending on the temperature, an amount of water sufficient for steam generation is added via the pump. In the present case, the water reservoir 12 is integrated in the housing 2 of the steam iron 1. However, it is conceivable from embodiments of the invention in which the water reservoir 12 is present externally and the line 14 is formed as a water hose for connection of the external water reservoir.

The relationship between the temperature and the amount of water is preferably stored in the controller 26. About a power cable 18, the steam iron 1 can be connected to the mains and can be switched by means of a main switch 20. For example, when connecting the power cord to the domestic network, the steam iron 1 is turned on and the control 26, the heating of the soleplate of the iron 6 is initiated and controlled, and optionally steam generated by the pump 16 in accordance with the control 26 water in the steam chamber is delivered. Furthermore, a temperature controller 50 is shown, which is connected via a line 52 to the controller 26. By means of this temperature controller, a preset temperature can be set by the user.

To determine whether the steam iron is used, for example, a sensor 22 is arranged on the handle of the steam iron, with which it can be detected whether a user holds the iron. For example, this sensor is designed as a capacitive sensor and connected by means of a line 24 to the controller 26. Further, for example, the steam iron may include a position sensor 32 for determining whether the iron is in a horizontal position and a regular steam ejecting operation is permitted in ironing. Furthermore, a temperature sensor 57 is shown, which is connected by means of a line 54 to the controller 26. About the example electronically designed temperature control can be timely and accurately controlled and readjusted the temperature of the soleplate by a current temperature is detected and a corresponding Heating power is set by the controller. As a component in such a control, for example, a thermal resistance can be used.

Sensor signals from the bearing sensor 32 and from the handle sensor 22 can be evaluated as a function of time in order to prevent unnecessary switching operations and to ensure reliable operation of the steam iron. By means of the position sensor 32, it can be ensured, for example, that the pump 16 is deactivated in an operating position of the iron deviating from the horizontal. For this purpose, the controller 26 receives a position signal via the line 34 and controls the pump according to the storage signal accordingly. For example, in order to still be able to deliver steam in a horizontal or horizontal position deviating position of the steam iron, the steam iron, for example, an instant steam request switch 40 which is connected by means of a signal line 60 to the controller 26 and act on the steam chamber 8 via the connection 44 can. If the immediate steam request switch is actuated, activation of the sole heating 10 is for example directly initiated in the control and it is checked via the temperature sensor 57 whether the sole has a sufficient temperature for generating steam. If this is the case, the pump 16 is activated and water is introduced into the steam chamber of the sole. Specifically, it is possible to specify via a temperature preselection set on the temperature controller which temperature is set and in the controller a predetermined temperature is compared with the presence of a steam request signal. In particular, this steam request signal can also be generated by the control itself. If a comparison device within the controller determines that a steam request signal is present and a specific temperature preselection, it may be determined on a case-by-case basis that a temperature of the sole that deviates from the temperature preselection is set. Specifically, in a lower temperature range, for example, in a temperature range adjustable as a point on the temperature controller 50, which is usually defined to be between 70 ° and 120 ° C, an elevated sole temperature can be set. For example, a temperature between 100 ° C and 180 ° C, preferably between 100 ° and 145 ° C, so that even in a lower temperature preselection range reliably vapor without droplet formation can be generated.

About the temperature sensor 57 and the temperature controller 50 can be determined at any time by the controller 26, which temperature is present at the sole 6 and which temperature is selected. Depending on these two temperatures, the pump can then be activated in accordance with a steam demand by the controller to evaporate water. The pump power is determined by the controller 26 in particular so that no droplets form during evaporation. The temperature at preselection on temperature controller 50 typically refers to dry tissue. Once water is allowed to evaporate, the bottom temperature drops and should be returned to set point temperature while controlling the pumping power so that the pump 16 delivers an adjusted amount of water in response to a decreasing temperature to prevent droplet formation during steam generation ,

As FIG. 2 2, there is a relationship between a delivery rate of a water pump 16, here denoted 210, and a temperature 220. For example, the temperature settings 226 corresponding to a point on the temperature controller 50 of the iron 230 are the two points corresponds to the controller 50 of the iron and 250, the three points on the controller 50 of the iron corresponds to a straight line. With 225, 235 and 265, a corresponding control range for the respective temperature range can be specified. For one point, for example, temperature variations between 70 ° and 120 ° C are allowed, while for two points temperature variations between 100 ° and 160 ° C are allowed and furthermore for three points the temperature should be between 140 ° and 210 ° C. In the in FIG. 2 a user default 277 is shown. The default 277 corresponds to a temperature and a pump power. However, as soon as water is pumped onto the sole via the pump, the temperature of the sole sinks, which is symbolized by the arrow 273. The temperature can be measured via the temperature sensor 57 and the controller regulates the delivery rate of the pump to prevent droplets from forming in the steam. The control range here is designated by 280, for example. Generally speaking, the lower the temperature, the greater the risk of droplets forming as steam is generated and temperature falls.

For example, the steam generation may be initiated automatically by an ironing program, or triggered by hand with an instant steam selector switch by the user become. For example, upon activation of the water pumping pump into the steam chamber, the heating element is also turned on to generate steam on the soleplate in the steam chamber without delay.

As FIG. 3 shows, according to the invention, the steam generation can be improved in a lower temperature preset range. For this purpose the diagram is analogous to FIG. 2 applied to the top of the pump power 210 and to the right the temperature 220. Similarly, the temperature settings 226, 240 and 250 are analogous to FIG. 2 shown. The same applies to the control areas 225, 235 and 245, which are assigned to the corresponding settings. In this particular case, if the temperature preselection is at a point and in the event that there is a steam demand, then a temperature setpoint 230 is set in the controller which is actually above the limit which belongs to a one-digit prefix. For example, such a temperature specification can be between 120 ° C and 180 ° C, preferably between 120 and 145 ° C, and especially 130 ° C. Accordingly, according to this specification, the delivery rate of the pump is controlled to generate steam, for example at a point 328. The water conveyance to the sole causes it to cool, as indicated by an arrow 333. The control is accordingly adapted to the temperature which exceeds the Temperature sensor 57 is detected to regulate again high and at the same time to regulate the flow rate of the pump 16 so that no droplets form. That is, with decreasing temperature less water is pumped and with increasing temperature more water is pumped.

FIG. 4 shows the example of a temperature profile as according to the method of the invention, the temperature can be controlled. Diagram 400 shows temperature 410 up and time 420 right. For example, with 430, a temperature is shown at a one-point prefix, which should typically be between 70 ° and 120 ° C, and which is defined in the lowest temperature range for sensitive tissue. If it is determined that there is a steam demand, for example via a comparator in the controller that determines that a ironing program is requesting steam, or if a user has pressed the instant steam switch and wants a steam blast, the temperature is raised to a level 440 to To set the sole a temperature that allows steam generation without droplet formation. As soon as the steam demand is removed later, the temperature is regulated back to a level 450, which essentially corresponds to the initial level 430 and thus the preset temperature for the treatment of sensitive tissue, which is set on the temperature controller. The Applicant has found through experiments that an elevated sole temperature at a "one-point" setting of the temperature controller, ie the lowest temperature setting on the iron for gentle tissue treatment and not to damage the fabric leads. This is due, for example, to the fact that the steam shown has 100 ° C and thus the temperature is within the specification of the tolerance range for a point. Further, the fabric is quickly wetted by the generated steam, leaving it only 100 ° C warm, although the sole temperature may be higher.

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.

REFERENCE LIST FIG. 1

1

steam iron

2

casing

4

Handle

6

sole

8th

steam chamber

10

heater

12

Water reservoir

14

fluid line

16

pump

18

power cable

20

Main control unit

22

grip sensor

24

connecting line

26

control

28

supply line

30

Rear

32

position sensor

34

Binding line to the position sensor

36

Pump control line

40

Instant steam request switch

60

Line for control of instant steam request switch

50

thermostat

54

Line to the controller

57

temperature sensor

52

Line from temperature controller to controller

Claims (11)

Steam iron (1) for domestic use with a steam chamber (8) and a heater (10), and a water reservoir (12) and a pump (16) for conveying cold water into the steam chamber (8) and a controller (26) for the pump power of the pump, which is adapted to control the pump power in response to a sole temperature and / or a sole temperature preset setting of the steam iron, characterized in that
the controller (26) is adapted to control the sole temperature in response to a temperature preference setting (50), the controller (26) having a comparator which compares and adjusts a temperature preference setting to a presence of a vapor demand signal depending on the temperature preference setting and to set the presence of a steam request signal, a temperature different from the temperature setting setting sole temperature. The steam iron (1) of claim 1, wherein the controller (26) is further adapted to increase the sole temperature. A steam iron (1) according to claim 2, wherein the controller is adapted to increase the sole temperature in a lower temperature preset range. A steam iron according to any one of claims 1 to 3, wherein there is a temperature sensor (57) which measures the sole temperature and which is connected to the controller (26). A steam iron (1) according to any one of claims 1 to 4, comprising an instant steam request switch (40) for generating a request signal (60) connected to the controller (26). A steam iron (1) according to any one of the preceding claims, wherein the controller is adapted to immediately turn on the heater (10) in response to a presence of a steam demand signal. A steam iron (1) according to any one of the preceding claims, wherein the controller (26) is adapted to generate the steam demand signal. Steam iron (1) according to one of the preceding claims, equipped with an external cold water storage tank. A method of operating a steam iron (1) having a steam chamber (8) integrated in the bottom (6) to determine whether there is a steam demand, characterized in that depending on the presence of a steam demand and a pre-set preset temperature in the presence of a steam demand one of the preset temperature deviating sole temperature is set. A method of operating a steam iron according to claim 9, wherein an elevated temperature is set. A method for operating a steam iron according to one of claims 9 or 10, wherein a presence of a steam demand directly the heater (8) is activated.

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