WO2013124640A1

WO2013124640A1 - Steam generating device, method of cleaning said device and method generating steam with said device

Info

Publication number: WO2013124640A1
Application number: PCT/GB2013/050398
Authority: WO
Inventors: Jamie LENNOX
Original assignee: Jaleno (Asia) Limited
Priority date: 2012-02-20
Filing date: 2013-02-19
Publication date: 2013-08-29
Also published as: GB201202802D0

Abstract

A steam generating device (100) comprising a reservoir (200) operable to contain water and an impurity collecting means (300). The reservoir and the impurity collecting means are removably attached to each other to facilitate easier cleaning of the impurity collecting means and / or the reservoir.

Description

STEAM GENERATING DEVICE, METHOD OF CLEANING SAID DEVICE AND METHOD

GENERATING STEAM WITH SAID DEVICE

FIELD OF INVENTION

The present invention relates to a device for heating water to produce steam. More particularly the present invention relates to a portable device, such as a home appliance, operable to generate steam.

BACKGROUND OF THE INVENTION

Steam generating devices are used in a range of applications, such as portable cleaning devices and irons. Such devices comprise a heating element which extends into, or around, a water containing reservoir. In use, the heating element vaporises the water in the reservoir to generate steam. The steam is collected via steam collecting means and dispensed via an outlet. Generally, mains water used in such devices and is of low purity, particularly due to it containing lime or other impurities. During vaporisation these impurities are left deposited on the heating element, steam collecting means and other associated components. This deposition can lead to a blockage in the device, or otherwise reduced performance.

CN 2092938 discloses a kettle with mechanical means for removing lime scale, which comprises a shaft with four screens, operable to absorb scale, mounted thereto. The mechanical means occupies a significant volume inside the kettle, and is also likely to add substantial cost. Furthermore, it does not directly clean the heating element or other associated components susceptible to scale.

EP 0514271 and FR2704559 discloses a steam generating device comprising a heating element which is circular and elongate, with an antifouling device attached thereto. The antifouling device comprises a helix shaped coil, which is arranged about the heating element such that it is moved relative the heating element by movement of water, together with thermal expansion, to prevent formation of lime scale on the heating element. Here the heating element is restricted to configurations with match the spring, for instance, it is not possible to substantially alter the size of the heating element if a greater surface area is required. Furthermore, the heating element and coil may still be susceptible to lime scale deposits.

It is an object of aspects of the present invention to overcome at least one of the above or other problems. More particularly, an object is to provide a steam generating device with improved impurity deposit removal capability. SUMMARY OF THE INVENTION

According to a first aspect of the invention there is provided a steam generating device comprising: a reservoir operable to contain water; an impurity collecting means, wherein the reservoir and the impurity collecting means are removably attached to each other.

Advantageously, the impurity collecting means can be preferably removed from the reservoir to facilitate easier cleaning of the impurity collecting means and / or the reservoir. Preferably, in a first operative position the impurity collecting means is inserted substantially into the reservoir, in a second inoperative position the impurity collecting means is substantially withdrawn from the reservoir, whereby the removable attachment is operable to enable movement between the first operative position and the second inoperative position. Preferably, reservoir and / or the impurity collecting means comprises a heating element.

Preferably, the impurity collecting means includes an impurity collecting portion, which comprises a surface area increasing means. Preferably, the surface area increasing means comprise a plurality of corrugations, or ridges, which may be a spiral ridge. Preferably, the impurity collecting portion is arranged at an exterior of the impurity collecting means. Advantageously, the increased area of the surface area increasing means preferably enables is to retain more impurities thereon.

Preferably, the impurity collecting means and reservoir are arranged to transfer heat between each other, preferably by convective heat transfer.

Preferably, the impurity collecting means includes a steam collecting portion, the steam collecting portion preferably being located at an interior of the impurity collecting means. Preferably, the steam collecting portion comprises at a first end of the impurity collecting means, an inlet operable to receive water and / or water vapour, preferably, the impurity collecting means comprises at a second end an outlet operable to transmit water vapour from the steam collecting portion. Preferably, the impurity collecting means is elongate, preferably the impurity collecting means is substantially hollow, preferably the impurity collecting means is substantially cylindrical.

Preferably, the impurity collecting portion comprise a material operable to attract impurities from water, preferably the material comprises an Aluminium alloy.

Preferably, the reservoir comprises a reservoir interior suitable for housing the impurity collecting means. Preferably, the reservoir comprises at a distal end an inlet operable to receive water.

Preferably, the inlet of the reservoir and impurity collecting portion of the impurity collecting means, when in the first operable position, are configured such that water from the inlet is contacted substantially with the impurity collecting portion. Advantageously, water that enters the reservoir preferably contacts the impurity collecting portion where it is vaporised. In this way, preferably the majority of impurities in the water are deposited on the impurity collecting portion which is easy to remove and clean. Preferably, the reservoir interior comprises a pressure relief device, preferably operable to relieve a pressure of the reservoir interior if the pressure exceeds a first pressure. Preferably, the pressure relief device comprises an adjustment means operable to adjust a magnitude of the first pressure. Preferably, the pressure relief device is located at a proximal end of the reservoir interior, wherein, in use, the proximal end is situated at a bottom of the steam generating device. Advantageously, in use, the pressure relieve device is preferably arranged to vent hot water / water vapour away from a user. Preferably, the reservoir comprises a heat conductive material, such as an alloy.

Preferably, the heating element, when situated on the reservoir, is embedded in the conductive material.

Preferably, the impurity collecting means when in the first operative position is arranged such that the outlet of the impurity collecting means extends through the reservoir.

Optionally, the reservoir interior comprises a surface area increasing means operable to increase heat transfer from the reservoir to water contained by the reservoir. Preferably, the surface area increasing means comprises a plurality of ridges. Advantageously, the surface area increasing means preferably enables improved heat transfer.

Optionally, the reservoir interior is substantially smooth. Advantageously, it is preferably easier to clean.

Preferably, the removable attachment comprises a screw fitting, bayonet or the like. Preferably, the removable attachment comprises locking means. Preferably, the removable attachment is configured to inter-connect the reservoir to the impurity collecting means proximate the distal end of the reservoir and proximate the second end of the impurity collecting means.

Preferably, the removable attachment comprises sealing means operable to hermetically seal the impurity collecting means and reservoir interior. Preferably, there are a plurality of sealing means, with a first sealing means being arranged between the outlet of the impurity collecting means and the interior of the reservoir, and a second sealing means being arranged between the outlet and removable attachment, preferably the first and second sealing means defining a vent region. Preferably, a nozzle is arranged to interconnect the vent region and exterior of the steam generating device to thereby define a steam outlet.

Advantageously, the sealing means, nozzle, and outlet of the impurity collecting means preferably define a steam outlet which is relatively simple to fabricate and can be readily assembled / disassembled when removing/attaching the impurity collecting means from the reservoir.

Preferably, an outer surface of the reservoir comprises an insulating material. Preferably, the steam generating device comprises a temperature sensing means

Preferably the temperature sensing means is operable to sense a temperature within the reservoir, the temperature sensing means preferably being connected to a control system which is configured to control a temperature of a heating element such that the temperature within the reservoir remains within a safe operating range.

Preferably, the steam generating device comprises a pressure relief device, the pressure relief device being operable to relieve a pressure in the reservoir interior. Preferably, the steam generating device comprises notification means operable to signal to a user when the steam generating device requires cleaning. Preferably, the notification means comprises a data recording means, which is operable to record a service time since a previous clean, and once a first service time has been exceeded, notify a user that cleaning is required.

Preferably the device comprises a thermo fuse arranged to switch off the heating element once a pre-defined temperature in the reservoir has been exceeded. Preferably the stem generating device comprises a filtering means arranged to filter water entering the reservoir.

According to a second aspect of the present invention there is provided a portable appliance comprising the steam generating device in accordance to the first aspect of the present invention.

According to a third aspect of the present invention there is provided a steam cleaner comprising the steam generating device in accordance to the first aspect of the present invention.

According to a fourth aspect of the present invention there is provided an iron comprising the steam generating device in accordance to the first aspect of the present invention. According to a fifth aspect of the present invention there is provided a kit of parts for a steam generating device in accordance to the first aspect of the present invention.

According to a sixth aspect of the present invention there is provided a method of cleaning a steam generating device comprising steps of: removing an impurity collecting means from a reservoir operable to contain water, the reservoir being removably attached to the impurity collecting means; cleaning the reservoir and / or cleaning the impurity collecting means.

Preferably, the method includes a step of cleaning an impurity collecting region of the impurity collecting means, the impurity collecting portion comprising a surface area increasing means such as a plurality of corrugations or ridges. Preferably, the method includes a step of cleaning the impurity collecting portion using an instrument specifically adapted to clean the surface area increasing means.

Optionally, the method includes a step of cleaning a surface area increasing means of the reservoir. Preferably, the method includes cleaning the surface area increasing means of the reservoir using an instrument specifically adapted to clean the surface area increasing means.

According to a seventh aspect of the present invention there is provided a method of generating steam comprising steps of: supplying water to a reservoir through an inlet of the reservoir; collecting impurities from the water using impurity collecting means, wherein the impurity collecting means is arranged such that water entering the reservoir via the inlet substantially contacts the impurity collecting means, the impurity collecting means being operable to vaporize the water on contact and to thereby collect impurities. Advantageously, impurities in the water are preferably substantially collected on the impurity collecting means rather than associated components which are harder to clean.

Preferably, the method includes a step of dispensing the vaporized water though an outlet of the steam generating device.

All of the features contained herein may be combined with any of the above aspects and in any combination.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention, and to show how embodiments of the same may be carried into effect, reference will now be made, by way of example, to the accompanying diagrammatic drawings in which:

Figure 1 shows a side cross-sectional view of a steam generating device according to the present invention; Figure 2 shows a side view of an impurity collecting means of the steam generating device of figure 1 ;

Figure 3 shows a side view of a reservoir of the steam generating device of figure 1 ; and

Figure 4 shows a method of cleaning the steam generating device of figure 1 .

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Figure 1 shows a steam generating device 100, which has a reservoir 200 operable to contain water (not shown) and an impurity collecting means 300. The reservoir 200 is connected to the impurity collecting means 300 by a removable attachment 400. In figure 1 the steam generating device 100 is shown in a first operative position 150, in which the impurity collecting means 300 is housed within the reservoir 200. In this embodiment the reservoir 200 includes an electrical heating element 202 which is electrically connected to a mains supply (not shown), or portable power supply unit (not shown). The heating element 202 is operable to vaporise water within the reservoir 200. In an alternate embodiment (not shown) a heating element may be additionally or exclusively positioned on the impurity collecting means 300. The impurity collecting means 300 and reservoir 200 when arranged in the first operative position 150 are situated proximate each other, such that heat can be transferred between both components. This may be achieved by radiation and / or convective heat transfer from water/water vapour therebetween.

Figure 2 shows the impurity collecting means 300 in more detail. Here the impurity collecting means 300 comprises an elongate, substantially cylindrical tube, with a first end 302 and second end 304. An exterior surface 306 of the impurity collecting means 300 includes an impurity collecting portion 320, which comprises surface area increasing means 322. In this embodiment the surface area increasing means 322 comprises a plurality of corrugations 324 which are formed by pressing or casting, preferably to form a spiral ridge of thread. In another embodiment (not shown) the surface area increasing means 322 comprises a plurality of ridges affixed to the cylindrical tube and arranged to extend outwardly from the cylindrical tube.

The first end 302 of the impurity collecting means 300 includes an inlet 308 arranged to transfer steam, from the reservoir 200, to a steam collecting portion 340. Here the steam collecting portion 340 comprise a passageway that extends through an interior 310 of the impurity collecting means 300, which is operable to convey steam to an outlet 312 at the second end 304. Here the outlet 312 comprises one or more apertures which are arranged to extend through a wall of the second end 304 of the impurity collecting means 300. The impurity collecting portion 320 comprises a material, or coating operable to attract impurities from water present in the reservoir. In this embodiment the material is an aluminium alloy.

Figure 3 shows the reservoir 200 in more detail. Here the reservoir 200 comprises a reservoir interior 220 in the form of a substantially cylindrical cut-out, which is configured to house the impurity collecting means 300. The reservoir 200 has a distal end 204 and proximal end 206. The distal end 204 has an inlet 240 arranged to transfer water from a reservoir exterior 222 to the reservoir interior 220. Referring back to figure 1 , the reservoir inlet 240 and impurity collecting means 300, when in the first operable position 150, are arranged such that a substantial quantity of the water entering the reservoir interior 220 via the reservoir inlet 240 is sprayed over the impurity collecting portion 320 of the impurity collecting means 300. This is achieved by arranging the impurity collecting portion 320 substantially beneath the inlet 240 such that water travels along it under the influence of gravity. The high surface area of the surface increasing means further enhances this effect by increasing the area of the impurity collecting portion 320 available to contact the water. Yet further, the inlet 308 is positioned proximate the lowest point of the reservoir interior 220, with a relatively small gap therebetween, such that water entering the reservoir has to travel the majority of the extent of the reservoir to the inlet 308. In this way, in use, the deposition of any impurities in the water is focused on the impurity collecting portion 320.

Referring back to figure 3, the reservoir 200 further includes a pressure relief device 250, such as a non-return valve. The pressure relief device 250 is arranged to interconnect the reservoir interior 220 to the reservoir exterior 222, and is configured such that if a pressure at the reservoir interior 220 exceeds a safe value, which is typically in the region of 5 Bar, then fluid is vented to the reservoir exterior 222. The pressure relief device 250 is situated at the proximal end 206 of the reservoir 200, in this way fluid can be vented proximate a bottom of the steam generating device 100 and away from a user. The pressure relief device 250 includes an adjustment means (not shown) operable to adjust the safe value.

The reservoir 200 comprises a conductive material, such as an alloy. Here the heating element 202 comprises a coil which is embedded in the reservoir 200 material, however, it will be appreciated that in alternative embodiments (not shown) the heating element 202 can be arranged in any position operative to transfer heat to the reservoir 200 by means of conduction.

Here the reservoir interior 220 is substantially smooth, such a surface finish may be achieved by casting and / or machining. In this way it is easier to clean. In another embodiment (not shown), the reservoir interior 220 may comprise surface area increasing means, such as a plurality of ridges. In this embodiment the surface area increasing means enables improved heat transfer to the water and the impurity collecting means 300. The exterior 222 of the reservoir 200 includes a layer of insulating material, such as a resin or plastic, which is arranged to house the reservoir 200, heating element 202 and other associated components. In this way heat escaping from the steam generating device 100 is reduced, which increases efficiency and safety of the user. Referring back to figures 1 - 3, the removable attachment 400 is arranged to interconnect the distal end 204 of the reservoir 200 and second end 304 of the impurity collecting means 300. Here the removable attachment 400 comprises a bayonet fitting. A lid 330 provides an actuation means for actuating the fitting and has outwardly extending protrusions 332 which are arranged to be rotatably engaged with corresponding slots 208 on the reservoir 200. In another embodiment, (not shown) the removable attachment 400 comprises a screw fit, or other suitable quick release means. Advantageously, the fitting secures the lid to the reservoir to reduce the likelihood of accidental removal in use.

The removable attachment, in addition to the above fitting, may further include locking means 410 (not shown), such as a catch on the lid / reservoir operable to engage with a latch on the other of the lid / reservoir. Advantageously, the locking means further secures the lid 330 to the reservoir 200 and further reduces the likelihood of accidental removal in use.

The lid 330 is securable to the reservoir 200 by an abutment surface 210 of the reservoir 200, which is shaped to co-operate with a corresponding abutment surface of the lid 332.

Referring back to figures 1 and 2, sealing means 500 are arranged to hermetically seal between the distal end 204 of the reservoir 200, and second end 304 of the impurity collecting means 300.

Here the sealing means 500 comprises a first sealing member 502 and second sealing member 506. The first sealing member 502 is situated in an annular groove 504 located to engage a seal between the outlet 312 of the impurity collecting means 300 and the interior of the reservoir 220. The second sealing member 506 is situated in an annular groove 508 located to engage a seal between the removable attachment 400 and the outlet 310 of the impurity collecting means 300. In this way the first and second sealing means 502, 506 define a vent region 600. The vent region 600 extends around a peripheral of the second end 304 of the impurity collecting means 300, and around the interior of the distal end 204 of the reservoir 200. The vent region 600 includes a nozzle 602, which is in fluid communication with the outlet 310 of the impurity collecting means 300. Hence steam is transferable through the steam collecting means 340 via the outlet 312 into the vent region 600, and to the nozzle 602, where is can be dispensed from the steam generating device 100.

Advantageously, the seal provided by first and second sealing members 502, 506 is disengageable and engageable by engaging / disengaging the removable attachment 400, and provides a sealed outlet which is relatively simple to fabricate. The sealing means 500 prevents water entering the reservoir interior 200 via the inlet

240 from contaminating the steam dispensed from the nozzle 602.

The steam generating device 100 further comprises a temperature sensing means (not shown), such as a thermo-couple, or thermometer. The temperature sensing means is operable to measure the temperature within the reservoir interior 220 and / or through the reservoir material. The temperature sensing means is operable to measure when a first temperature has been exceeded, and if so notify a user, and / or reduce the heat applied by the heating element 202 by means of a control system. In this way the temperature within the reservoir can be maintained within a safe operating range of 170 - 210°c.

The steam generating device 100 further comprises a thermo fuse which is arranged to sense when a safety limit temperature has been exceeded and permanently cut off heat applied to the heating element 202. In this embodiment the limit temperature is 240°c. The steam generating device further comprises notification means (not shown) operable to signal to a user when the steam generating device requires cleaning. The notification is achieved by a visual indicator, such as an LED, and / or an audio alert.

In one embodiment the steam generating device includes a filtering means, such as a calcium carbonate filter arranged to filter water entering the reservoir.

In one embodiment, the notification means includes a data recording means, which records the service time between cleans. This can be achieved by measuring the time electrical current has been supplied to the heating element 202, with the time being reset each time the removable attachment 400 is detached. In another embodiment, the notification means comprises a sensor situated at the reservoir interior 220 and / or the impurity collecting means 300, which is operable to detect impurity build-up. This can be achieved by a photo- diode and associated light source. The light-sensing surface of the photo-diode being arranged to become impaired with impurity build up. The dimensions of the reservoir 200 are in the region on 20cm - 1 m, with a diameter in the region of 5cm - 50 cm. In this way the steam generating device 100 is portable, and / or can be integrated in to an appliance such as an iron or steam cleaning device.

In use, water enters the reservoir interior 220 via the inlet 240. The inlet 240 may be connected by means of a valve (not shown) to a mains water supply or a second reservoir (not shown) operable to dispense water to the inlet 240. Water enters the reservoir interior 220 and is sprayed substantially over the impurity collecting portion 320 of the impurity collecting means 300. The impurity colleting region 320 is heated, by means of the heating element 202, such that any water contacting it is immediately vaporised, in this way the majority of any impurities in the water are deposited on to the impurity collecting means 300. The remaining water contacts the heated reservoir interior 220, where it is vaporised and any remaining impurities are deposited.

The steam enters the steam collecting means 340 via the inlet 308 and travels upwardly through the passageway of the steam collecting means 340. The vertical arrangement of the steam collecting means 320 substantially prevents water from travelling through steam collecting means 340. Steam exits the steam collecting means 320 via the outlet 312 and enters the vent region 600. Steam is then dispensed through the nozzle 602 for use.

During use, the user may decide to clean the steam generating device 100, by their own volition or when prompted by the notification means. Figure 4 shows cleaning of the steam generating device 100 in more detail. Figure 4a shows the steam generating device 100 prior to cleaning, in the first operative position 150, in which the impurity collecting means 300 is housed within the reservoir 200 and the attachment means 400 is in an engaged position. Figure 4b shows the steam generating device 100, in a second in-operative position 160, in which the impurity collecting means 300 has been removed from the reservoir 200 and the attachment means is in a disengaged position. In this position, impurities deposited on the impurity collecting portion 320 of the impurity collecting means 300 are removed. This is achieved by using an instrument 700 specifically adapted for cleaning. Here the instrument comprises a brush, with bristles optimised in rigidity and pitch to clean between the corrugations 324 without damaging the impurity collecting means 300. Cleaning performance may be enhanced by use of a solvent or abrasive / erosive compound. Figure 4c shows a similar operation being applied to the reservoir interior 220, wherein a corresponding instrument 702 is used to aid cleaning. Thereafter, the steam generating device 100 is returned to the first operative position 150 by inserting the impurity collecting means 300 into the reservoir 200 and moving the attachment means 400 to the engaged position. Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1 . A steam generating device comprising: a reservoir operable to contain water; an impurity collecting means, wherein the reservoir and the impurity collecting means are removably attached to each other.

2. The steam generating device as claimed in claim 1 , wherein in a first operative position the impurity collecting means is inserted substantially into the reservoir, and in a second inoperative position the impurity collecting means is substantially withdrawn from the reservoir, whereby the removable attachment is operable to enable movement between the first operative position and the second inoperative position.

3. The steam generating device as claimed in any preceding claim, wherein the reservoir and / or the impurity collecting means comprises a heating element.

4. The steam generating device as claimed in any preceding claim, wherein the impurity collecting means includes an impurity collecting portion, which comprises a surface area increasing means.

5. The steam generating device as claimed in claim 4, wherein the surface area increasing means comprise a plurality of corrugations, or ridges, or a spiral ridge.

6. The steam generating device as claimed in claims 2 - 5, wherein the impurity collecting portion is arranged at an exterior of the impurity collecting means.

7. The steam generating device as claimed in any preceding claim, wherein the impurity collecting means and reservoir are arranged to transfer heat between each other, preferably by convective heat transfer.

8. The steam generating device as claimed in any preceding claim, wherein the impurity collecting means includes a steam collecting portion, the steam collecting portion being located at an interior of the impurity collecting means.

9. The steam generating device as claimed in claim 8, wherein the steam collecting portion comprises at a first end of the impurity collecting means, an inlet operable to receive water and / or water vapour, and at a second end an outlet operable to transmit water vapour from the steam collecting portion.

10. The steam generating device as claimed in any preceding claim, wherein the impurity collecting means is elongate, and is substantially hollow and cylindrical.

1 1 . The steam generating device as claimed in claims 2 - 10, wherein the impurity collecting portion comprises a material operable to attract impurities from water that comprises an Aluminium alloy.

12. The steam generating device as claimed in any preceding claim, wherein the reservoir comprises a reservoir interior suitable for housing the impurity collecting means, wherein the reservoir comprises at a distal end an inlet operable to receive water.

13. The steam generating device as claimed in claim 12, wherein the inlet of the reservoir and impurity collecting portion of the impurity collecting means, when in the first operable position, are configured such that water from the inlet is contacted substantially with the impurity collecting portion.

14. The steam generating device as claimed in any preceding claim, wherein the reservoir interior comprises a pressure relief device, operable to relieve a pressure of the reservoir interior if the pressure exceeds a first pressure.

15. The steam generating device as claimed in claim 14, wherein the pressure relief device comprises an adjustment means operable to adjust a magnitude of the first pressure.

16. The steam generating device as claimed in claims 14 - 15, wherein the pressure relief device is located at a proximal end of the reservoir interior, wherein, in use, the proximal end is situated at a bottom of the steam generating device.

17. The steam generating device as claimed in any preceding claim, wherein the reservoir comprises a heat conductive material, such as an alloy, wherein the heating element is embedded in the conductive material.

18. The steam generating device as claimed in claims 9 - 17, wherein the impurity collecting means when in the first operative position is arranged such that the outlet of the impurity collecting means extends through the reservoir.

19. The steam generating device as claimed in any preceding claim, wherein the reservoir interior comprises a surface area increasing means operable to increase heat transfer from the reservoir to water contained by the reservoir.

20. The steam generating device as claimed in claim 19, wherein the surface area increasing means comprises a plurality of ridges.

21 . The steam generating device as claimed in claims 1 - 19, wherein the reservoir interior is substantially smooth.

22. The steam generating device as claimed in any preceding claim, wherein the removable attachment of the reservoir and impurity collecting means comprises a screw fitting, bayonet or the like.

23. The steam generating device as claimed in any preceding claim, wherein the removable attachment comprises locking means to lock the reservoir and impurity collecting means together.

24. The steam generating device as claimed in claims 1 1 - 23, wherein the removable attachment is configured to inter-connect the reservoir to the impurity collecting means proximate the distal end of the reservoir and proximate the second end of the impurity collecting means.

25. The steam generating device as claimed in any preceding claim, wherein the removable attachment comprises sealing means operable to hermetically seal the impurity collecting means and reservoir interior.

26. The steam generating device as claimed in claim 25, wherein there are a plurality of sealing means, with a first sealing means being arranged between the outlet of the impurity collecting means and the interior of the reservoir, and a second sealing means being arranged between the outlet and removable attachment.

27. The steam generating device as claimed in claim 26, wherein the first and second sealing means define a vent region, wherein a nozzle is arranged to interconnect the vent region and exterior of the steam generating device to thereby define a steam outlet.

28. The steam generating device as claimed in any preceding claim, wherein an outer surface of the reservoir comprises an insulating material.

29. The steam generating device as claimed in any preceding claim, wherein the steam generating device comprises a temperature sensing means, which is operable to sense a temperature within the reservoir, the temperature sensing means preferably being connected to a control system which is configured to control a temperature of a heating element such that the temperature within the reservoir remains within a safe operating range.

30. The steam generating device as claimed in any preceding claim, wherein the steam generating device comprises a pressure relief device, the pressure relief device being operable to relieve a pressure in the reservoir interior.

31 . The steam generating device as claimed in any preceding claim, wherein the steam generating device comprises notification means operable to signal to a user when the steam generating device requires cleaning.

32. The steam generating device as claimed in claim 31 , wherein the notification means comprises a data recording means, which is operable to record a service time since a previous clean, and once a first service time has been exceeded, notify a user that cleaning is required.

33. The steam generating device as claimed in any preceding claim, wherein the steam generating device comprises a thermo fuse arranged to switch off the heating element once a pre-defined temperature in the reservoir has been exceeded.

34. The steam generating device as claimed in any preceding claim, wherein the steam generating device comprises a filtering means arranged to filter water entering the reservoir.

35. A portable appliance comprising the steam generating device in accordance to any one of claims 1 - 34.

36. The portable device as claimed in claim 35, wherein the portable device is an iron.

37. A steam cleaner comprising the steam generating device in accordance to any one of claims 1 - 36.

38. A kit of parts for a steam generating device which when assembled comprises the steam generating device in accordance with any one of claims 1 - 37.

39. A method of cleaning a steam generating device comprising steps of: removing an impurity collecting means from a reservoir operable to contain water, the reservoir being removably attached to the impurity collecting means; cleaning the reservoir and / or cleaning the impurity collecting means.

40. The method as claimed in claim 39, wherein the method includes a step of cleaning an impurity collecting region of the impurity collecting means, the impurity collecting portion comprising a surface area increasing means such as a plurality of corrugations or ridges.

41 . The method as claimed in claims 39 - 40, wherein the method includes a step of cleaning the impurity collecting portion using an instrument specifically adapted to clean the surface area increasing means.

42. The method as claimed in claims 39 - 40, wherein the method includes a step of cleaning a surface area increasing means of the reservoir.

43. The method as claimed in claims 39 - 41 , wherein the method includes cleaning the surface area increasing means of the reservoir using an instrument specifically adapted to clean the surface area increasing means.

44. A method of generating steam comprising steps of : supplying water to a reservoir through an inlet of the reservoir; collecting impurities from the water using impurity collecting means, wherein the impurity collecting means is arranged such that water entering the reservoir via the inlet substantially contacts the impurity collecting means, the impurity collecting means being operable to vaporize the water on contact and to thereby collect impurities.

45. The method as claimed in claim 44, wherein the method includes a step of dispensing the vaporized water through an outlet of the steam generating device.