EP3444397B1 - Ironing device and method for controlling a heating unit of an ironing device - Google Patents

Description

The invention relates to an ironing device and a method for controlling a heating unit of an ironing device.

With steam generators in steam ironing stations, a compromise is usually made between short standby times and high amounts of steam. For example, a water heater can generate small amounts of steam very quickly, but if the steam is used for a long time, its performance will drop. A boiler, on the other hand, can buffer a permanent load better, but it takes a long time to start up to heat a large volume.

Such a generic steam generator is in the WO 2011/080026 A2 disclosed.

Against this background, the present invention has for its object to provide an improved ironing device and an improved method for controlling a heating unit of an ironing device.

According to the invention, this object is achieved by an ironing device and a method having the features of the main claims. Advantageous refinements and developments of the invention result from the following subclaims.

The invention offers the advantage that by combining a steam generator unit with a storage container, for example in the form of a structure in which an inner boiler is arranged in an outer boiler, steam can be made available for immediate ironing after a short heating-up time, while the positive ones Features of a boiler such as high amounts of steam and steam stability with a slight delay are available. For example, the heating remains active during short breaks to change or change the textiles to be ironed, in order to produce additional quantities of steam, which are then buffered and ready for long bursts of steam. Advantageously, only a few additional parts are required for this. Above all, there is no need for additional heating.

• einer mit einer Flüssigkeit befüllbaren Dampferzeugungseinheit zum Erzeugen von Dampf durch Verdampfen der Flüssigkeit;
• einem Speicherbehälter zum Speichern von von der Dampferzeugungseinheit erzeugtem Dampf;
• einem Koppelventil, das ausgebildet ist, um die Dampferzeugungseinheit und den Speicherbehälter fluidisch miteinander zu koppeln, wenn ein Innendruck der Dampferzeugungseinheit einen Betriebsdruck erreicht; und
• einem Wechselventil mit einem mit dem Speicherbehälter gekoppelten ersten Eingang, einem mit der Dampferzeugungseinheit gekoppelten zweiten Eingang, und einem Ausgang zum Bereitstellen eines Dampfvolumenstroms abhängig von einem am ersten Eingang und am zweiten Eingang anliegenden Druck.

An ironing device with the following features is presented:

• a steam generating unit that can be filled with a liquid, for generating steam by evaporating the liquid;
• a storage tank for storing steam generated by the steam generating unit;
• a coupling valve configured to fluidly couple the steam generating unit and the storage container to one another when an internal pressure of the steam generating unit reaches an operating pressure; and
• a shuttle valve with a first input coupled to the storage container, a second input coupled to the steam generating unit, and an output for providing a steam volume flow depending on a pressure present at the first input and at the second input.

An ironing device can be understood to mean, for example, a steam iron or a steam ironing station. Depending on the embodiment, the steam generating unit can be a water heater or a boiler. A storage tank can be understood as a boiler. For example, the volume of the steam generating unit and the storage container can differ from one another. A coupling valve can be understood to mean, for example, a pressure relief valve which enables the steam to flow in only one direction of flow. An operating pressure can be understood to mean a pressure at which the ironing device can be operated. The shuttle valve can, for example, be a simple mechanical valve with a sliding body for sealing either the first inlet or the second inlet in the sense of a non-exclusive OR link. The shuttle valve can be designed to release either the first input or the second input or both inputs at the same time, depending on a pressure applied to the two inputs.

The arrangement of a boiler for steam generation in a boiler enables rapid steam readiness with a high storage volume.

According to one embodiment, the steam generating unit can be arranged at least in sections within the storage container. As a result, the steam in the storage container can be heated by means of the steam generation unit without additional heating.

According to a further embodiment, the steam generating unit can have a smaller volume than the storage container. As a result, the time required for the vaporization of the liquid by the steam generation unit can be kept short.

Depending on the embodiment, the steam generating unit can be designed as a continuous-flow heater, as a further storage container or as a combination of both. As a result, the steam can be generated in different ways depending on the requirements.

The ironing device can have a control valve downstream of the shuttle valve for changing the steam volume flow. The control valve can be, for example, a shut-off valve. This enables the steam volume flow to be adjusted in a controlled manner to a steam requirement.

The coupling valve can advantageously be designed as a spring-loaded check valve. As a result, the coupling valve can be provided particularly inexpensively.

The ironing device can also have a heating unit for heating the steam generating unit and a control unit. The control device can be designed to control the heating unit as a function of an internal pressure of the storage container. In the present case, a control device can be understood to mean an electrical device that processes sensor signals and outputs control and / or data signals as a function thereof. The control device can have an interface that can be designed in terms of hardware and / or software. In the case of a hardware configuration, the interfaces can be part of a so-called system ASIC, for example, which contains a wide variety of functions of the control device. However, it is also possible that the interfaces are separate, integrated circuits or at least partially consist of discrete components. In the case of software-based training, the interfaces can be software modules which are present, for example, on a microcontroller in addition to other software modules. A robust control of the heating unit can be ensured by this embodiment.

The control unit can be designed to switch off the heating unit when the internal pressure of the storage container reaches the operating pressure. This enables efficient and safe operation of the ironing device.

Finally, the approach presented here creates a method for controlling a heating unit of an ironing device according to one of the above embodiments, the method comprising at least the following step:
Outputting a drive signal for driving the heating unit using a pressure signal representing an internal pressure of the storage container.

This method can be implemented, for example, in software or hardware or in a mixed form of software and hardware, for example in a control unit.

Figur 1

eine schematische Darstellung eines Abschnitts eines Bügelgeräts gemäß einem Ausführungsbeispiel;

Figur 2

ein Diagramm zur Darstellung eines jeweiligen Innendruckverlaufs der Dampferzeugungseinheit und des Speicherbehälters beim Bügeln mit dem Bügelgerät aus Figur 1; und

Figur 3

ein Ablaufdiagramm eines Verfahrens gemäß einem Ausführungsbeispiel.

An embodiment of the invention is shown purely schematically in the drawings and is described in more detail below. It shows

Figure 1

is a schematic representation of a portion of an ironing device according to an embodiment;

Figure 2

a diagram showing a respective internal pressure profile of the steam generating unit and the storage container when ironing with the ironing device Figure 1 ; and

Figure 3

a flowchart of a method according to an embodiment.

Figure 1 shows a schematic illustration of a section of an ironing device 100 according to an exemplary embodiment. The ironing device 100 comprises a steam generation unit 102, which can be filled with water via a water inlet 104. A heating unit 106, which is thermally coupled to the steam generation unit 102, is designed to heat the steam generation unit 102 and to cause the water therein to evaporate. Furthermore, the ironing device 100 has a storage container 108 for storing steam generated by the steam generation unit 102. As an example, the storage tank 108 is designed as an outer boiler with a significantly larger volume than the steam generation unit 102. The steam generating unit 102 is designed as an inner boiler and is arranged entirely within the storage tank 108. For guiding the steam into the storage container 108, the steam generating unit 102 has a coupling opening 110 opening into the storage container 108, which can be closed via a coupling valve 112, for example a spring-loaded pressure relief valve. The coupling valve 112 is designed to open the coupling opening 110 when an internal pressure of the steam generating unit 102 reaches an operating pressure of the ironing device 100. For example, the operating pressure represents a maximum allowable pressure. An example is in Figure 1 the heating unit 106 is also arranged in the storage container 108, so that the storage unit 108 can also be heated by means of the heating unit 106.

The storage container 108 is connected via a first steam line 114 to a first inlet 116 of a shuttle valve 118, which functions as a pressure switch. A second inlet 120 of the shuttle valve 118 is connected to the steam generating unit 102 via a second steam line 121. Furthermore, the shuttle valve 118 has an outlet 122, also called a steam outlet, via which the steam is conducted, for example, to an iron soleplate of the ironing device 100. Located within the shuttle valve 118 is a sliding body 124 which is displaceable between the two inlets 116, 120 and which is designed to release the first inlet 116 when a pressure present at the second inlet 120 is less than a pressure present at the first inlet 116, or that to release the second input 120 when the pressure present at the first input 116 is lower than the pressure at the second inlet 120, or to release both inlets 116, 120 if the pressure at the first inlet 116 and the pressure at the second inlet 120 are equal.

Optionally, the output 122 is preceded by a control valve 126, also called a steam valve, which is designed to regulate a steam volume flow emerging from the shuttle valve 118.

The shuttle valve 118 is arranged, for example, outside of the storage container 108 and outside of the steam generation unit 102.

According to this exemplary embodiment, the heating unit 106 is connected to a control unit 128, which is designed to switch the heating unit 106 on or off depending on an internal pressure of the storage container 108 by outputting a corresponding control signal 130. For this purpose, the control unit 128 receives a pressure signal 132 from a corresponding measuring device of the ironing device 100, which pressure signal represents an internal pressure of the storage container 108 measured by the measuring device.

According to one exemplary embodiment, the control unit 128 is designed to switch off the heating unit 106 when the evaluation of the pressure signal 132 shows that the internal pressure of the storage container 108 has reached the operating pressure.

According to the in Figure 1 In the exemplary embodiment shown, the ironing device 100 is realized with a boiler-in-boiler structure in which a small amount is first evaporated in the inner, smaller boiler 102 in order to keep the heating-up times short. The inner boiler 102 can also be designed as a water heater. If the steam is not demanded or not demanded in the amount produced, steam is initially generated further via the inner boiler 102 until the maximum pressure is reached. Instead of switching off the heating unit 106, as in conventional devices, the steam generation unit 102 is heated further, the steam reaching the outer boiler 108 via the coupling valve 112. The storage for the amount of steam can thus be increased while the first smaller amounts are already available to the user through the inner boiler 102. Due to the boiler-in-boiler structure, the waste heat from the inner boiler 102 can also be used to reheat the volume of the outer boiler 108 and to keep it at operating temperature without the need for further heating.

Via the shuttle valve 118, for example a simple mechanical valve, steam is removed from that of the two boilers 102, 108 in which the greater pressure is present, as a result of which both boilers 102, 108 are alternately emptied again. Will also be on the outside Boiler 108 reaches the maximum permissible pressure, the heating unit 106 is switched off by the control unit 128.

This avoids long heating times of three to five minutes. Furthermore, the disadvantages of pure instantaneous water heaters, which only provide reduced amounts of steam in continuous operation, can be avoided. The fact that the ironing device 100 provides permanently high amounts of steam in a short time can significantly increase the ease of use when ironing.

Figure 2 shows a diagram showing a respective internal pressure curve of the steam generating unit and the storage container when ironing with the ironing device Figure 1 . An example of a state profile with two boilers in the ironing device is shown. A first curve 200 represents the course of the internal pressure of the steam generating unit, here the inner boiler, and a second curve 202 the course of the internal pressure of the storage tank, here the outer boiler. The internal pressure is plotted as boiler pressure P on a y-axis. A horizontal line represents the operating pressure of the ironing device.

Below the diagram to show the internal pressure profiles are a second diagram with a third curve 204 to show actuation of the steam valve when ironing and a third diagram with a fourth curve 206 to show an operating state of the heating unit.

In a time period A, the cold ironing device is switched on, so that the ironing device heats up. Since initially only the inner boiler with a small volume is heated, the pressure rises quickly. The curve 200 is correspondingly steep here. At the end of period A, the operating pressure in the inner boiler has been reached and the ironing device is ready for use. The ironing device is therefore ready for operation much faster than if the volume of both boilers had already been heated.

Ironing does not start immediately in a period of time B, so that the available heating output is used further, since steam now escapes from the inner to the outer boiler through the pressure relief valve. Due to the large volume of the outer boiler, the pressure rises only slowly, while the nominal operating pressure is maintained in the inner boiler.

In a period C ironing. Steam is requested. Since the outer boiler is not yet at operating pressure, steam is only drawn from the inner boiler. The pressure drops. Steam is no longer released into the outer boiler.

In a time period D, the ironing is interrupted. The pressure in the inner boiler is increased again via the heating unit and quickly brought up to the nominal pressure.

In a time period E, steam flows again from the inner boiler into the outer boiler until it has also reached the operating pressure. From now on, the entire volume of both boilers is available for very long bursts of steam.

If steam is still not drawn off, the heating unit is switched off since no pressure increase is required. This is represented by a time period F.

When ironing again, steam is now drawn off from both boilers in a period G. Due to the common volume of both boilers, the pressure drops significantly more slowly than when the tank is removed exclusively. A significantly longer burst of steam is therefore possible. The heating unit is switched on again.

In a time period H, the inner boiler is brought back to operating pressure.

In a time period I, the outer boiler is brought back to operating pressure.

Figure 3 shows a flow diagram of a method 300 according to an embodiment. The method 300 for controlling a heating unit of an ironing device can, for example, be carried out by a control device, as described above on the basis of Figures 1 and 2nd is described. The pressure signal is initially received in an optional step 310. In a further step 320, the control signal for controlling the heating unit is generated and output using the pressure signal.

Claims (9)

1. Ironing device (100) having the following features:

   a steam generating unit (102), which can be filled with a liquid, for generating steam by evaporating the liquid;

   a storage container (108) for storing steam generated by the steam generating unit (102);

   characterised by

   a coupling valve (112) which is designed to fluidically couple the steam generating unit (102) and the storage container (108) to one another when an internal pressure of the steam generating unit (102) reaches an operating pressure; and

   a shuttle valve (118) having a first input (116) coupled to the storage container (108), a second input (120) coupled to the steam generating unit (102), and an output (122) for providing a steam volume flow depending on a pressure present at the first input (116) and/or at the second input (120).
2. Ironing device (100) according to claim 1, wherein the steam generating unit (102) is arranged inside the storage container (108) at least in portions.
3. Ironing device (100) according to either of the preceding claims, wherein the steam generating unit (102) has a smaller volume than the storage container (108).
4. Ironing device (100) according to any of the preceding claims, wherein the steam generating unit (102) is designed as a continuous-flow heater and/or as a further storage container.
5. Ironing device (100) according to any of the preceding claims, having a control valve (126) arranged downstream of the shuttle valve (118) for changing the steam volume flow.
6. Ironing device (100) according to any of the preceding claims, wherein the coupling valve (112) is designed as a spring-loaded check valve.
7. Ironing device (100) according to any of the preceding claims, having a heating unit (106) for heating the steam generating unit (102) and a control device (128) which is designed to control the heating unit (106) depending on an internal pressure of the storage container (108).
8. Ironing device (100) according to claim 7, wherein the control device (128) is designed to switch off the heating unit (106) when the internal pressure of the storage container (108) reaches the operating pressure.
9. Method (300) for controlling a heating unit (106) of an ironing device (100) according to either claim 7 or claim 8, wherein the method (300) comprises at least the following step: outputting (320) a control signal (130) for controlling the heating unit (106) using a pressure signal (132) representing an internal pressure of the storage container (108).

Images