EP3380786A1

EP3380786A1 - Device for generating steam and method of generating steam

Info

Publication number: EP3380786A1
Application number: EP16808582.7A
Authority: EP
Inventors: Mohankumar Valiyambath Krishnan; Yen Leng PANG
Original assignee: Koninklijke Philips NV
Current assignee: Koninklijke Philips NV
Priority date: 2015-11-26
Filing date: 2016-11-25
Publication date: 2018-10-03
Anticipated expiration: 2036-11-25
Also published as: WO2017089582A1; RU2700460C1; EP3380786B1; JP6506478B2; JP2018536832A; CN108291712A; CN108291712B; KR20180087335A

Abstract

The present invention is device (1) which may include a steaming element (2) with a surface (3). Water is introduced to the steaming element (2) from a water inlet arrangement (5) via a baffle (6). The plate (2) may be heated to a suitable temperature by the heating element (4) for steaming the water. The surface (3) for steaming water extends below the baffle (6) such that water flows from the baffle (6) onto the surface (3) of the steaming element (2). The steaming element (2) is configured such that water flows downwardly over the steaming element (2) to be evaporated.

Description

DEVICE FOR GENERATING STEAM AND METHOD OF GENERATING STEAM

FIELD OF THE INVENTION

The present invention relates to a steam generation device and a method of generating steam. BACKGROUND OF THE INVENTION

In many steaming devices, especially those with high steam rate deliveries, an electrical pump is used to deliver water on to a hot surface for steaming on demand. In some devices, water is delivered using an electrical pump from a dosing head as a single stream or jet on to the steaming surface typically when the user activates a trigger.

In some applications, the water is required to be spread over a larger area, for the purpose of better heat extraction, and thereby, better steaming performance. In such applications, a spray nozzle or a jet (or multijet) nozzle may be used to spread water over a large steaming surface.

As the water used could have salts and compounds that result in formation of scale, use of spray nozzles to spread water over the steaming surface should be avoided as the small nozzle openings are easily clogged with scale deposits causing the steaming function to fail.

A nozzle with a relatively large opening makes it more robust against scale clogging issues. However, the water may stream along a very narrow path along the steaming surface and a high steam rate production would thus require a very long steaming surface to ensure that water is completely evaporated by the steam generator, making the appliance bulky. Also, the jet impinging on the steaming surface results in splatter of water droplets which land on other parts of the steam generator causing low steaming efficiencies and long after-steaming effects (water drops landing on parts not directly heated take a longer time to evaporate).

OBJECT AND SUMMARY OF THE INVENTION

It is an object of the invention to propose a device for generating steam that avoids or mitigates above-mentioned problems. The invention is defined by the independent claims. The dependent claims define advantageous embodiments.

According to the present invention, there is provided a device for generating steam.

The present invention relates to a device for generating steam. The device comprises a steaming element having a surface for steaming water, a heating element to heat the steaming element to a predetermined temperature being at least above water evaporation temperature, a water inlet arrangement for dispensing water, and a baffle configured to receive the water dispensed by the water inlet arrangement, said baffle further configured to direct the water to the steaming element, wherein the surface for steaming water extends below the baffle such that water flows from the baffle onto the surface of the steaming element, and wherein the steaming element is configured such that water flows downwardly over the steaming element to be evaporated.

The baffle may help to spread the water out over a large width (or area) across the baffle to enable water delivery on to the steaming surface across the width (or area) of the steaming element. As the water is spread over a larger width or area, the surface for steaming water may be kept shorter (along the water flow direction on the steaming surface), resulting in a more compact device.

The steaming element may be a plate for steaming water or any structure that is configured to steam water. The steaming element may be referred to as a body of a steam generator. The heating element may be a heater, such as an electric heater.

The plate for steaming water may have a first end and a second end.

The device may further include a container comprising a bottom surface extending at least below an end of the plate, i.e. the first end of the plate. The container may be configured to collect scale falling down from the plate. The plate may have a further end, i.e. the second end, which is distal from the container.

The plate may be inclined at an angle (AO) compared to a horizontal direction (H) to define an upper end and a lower end. The lower end may be the first end and the upper end may be the second end. The bottom surface portion of the container may extend below the lower end of the plate. Water being dispensed onto the plate may run down the surface of the plate while steaming and may carry calc formed on the surface of the plate. As such, calc may be collected by the container placed below the plate. The container may be disposed adjacent to said plate. Dispensing water onto an angled heated plate or steaming element causes it to form a thin film and evaporate more quickly than if the plate were horizontal. As the film of water being fed onto the plate or steaming element is cold relative to the heated surface, any scale on the plate or steaming element will be subjected to thermal shock. That is, the cooling effect of the water (at least until it evaporates) and the heating effect of the surface will induce thermal stresses and strains in any scale that has formed on the surface and cause it to break apart and dislodge from the surface.

The inclination angle of the plate's surface causes the dislodged scale to travel down the plate's surface toward the lower end of the plate and, ultimately, into the container. Furthermore, the angle of inclination of the plate helps improve the efficiency of evaporation. The steep angle of the plate's surface ensures that water is continuously moved over said plate's surface by the action of gravity.

Preferably, the surface of the plate or steaming element may be a planar surface. Alternatively, the surface of the plate may be provided with rough or patterned structures (e.g. pillars / columns) to increase the surface area exposed to water during steaming.

In one embodiment, the baffle may have an edge in contact with the surface.

In another embodiment, the baffle may be spaced apart from the surface.

The baffle may have an edge spaced at a predetermined distance from the planar surface. The predetermined distance may be for instance any value between about 0.1 cm to about 5 cm, e.g. about 0.1 cm to about 2 cm.

The edge may be provided with a serrated profile. The serrated profile may comprise of a plurality of serrations or a saw-tooth like pattern. The serrated profile may ensure more uniform water spreading across the width of the baffle, especially when the device is tilted sideways. In other words, the serrated profile may increase the robustness of the device against side-ways tilts in providing uniform delivery of water by directing or conveying the water reaching the serrated edges as separate drops on to the steaming surface. The edge having the serrated profile may be a free edge of the baffle, i.e. an edge which is not attached to any other structure.

Preferably, the device comprises a directing structure configured to direct water back-scattered by the baffle to the plate or steaming element. The directing structure helps direct back-scattered water droplets due to inpringement of the water jet on the baffle. The water droplets that are back-scattered would be caught by the directing structure and be directed by the directing structure onto the surface of the plate or steaming element. The directing structure may extend from the baffle so that the directing structure overhangs the baffle. The directing structure and the baffle may form a continuous structure. The directing structure may have an edge having a serrated profile. The edge having the serrated profile may be a free edge. The edge of the directing structure may directly be above the free edge of the baffle.

Preferably, the directing structure comprises an opening configured to allow passage of the water from the water inlet arrangement onto the baffle. The water dispensed by the water inlet arrangement may pass through the opening without obstruction to the baffle while the directing structure may help direct back-scattered water droplets due to inpringement of the water jet on the baffle back to the plate.

Preferably, the water inlet arrangement comprises one or more jet nozzles. The one or more jet nozzles are configured to dispense water at high velocity. Jet nozzles are less susceptible (i.e. more robust) compared to spray nozzles, which may be easily clogged by scale. Scale may be caused by salts and compounds present in the water. In the case of devices with an inclined steaming surface, using a jet nozzle to deliver water directly to the surface may result in water streaming along a narow path down the steaming surface. A high steam rate production may thus require a very long steaming surface to ensure that water is evaporated by the heater. An appliance with a steam generator having a long steaming surface would be bulky. Also, the jet of water impinging on the steaming surface may result in splatter of water dropletes which may land in other parts of the steam generator, resulting in low steaming efficiencies and long after-steaming effects (water droplets landing on parts of the steam generator that are not directly heated may take a longer time to eavporate). The provision of a baffle may reduce the length of the steaming surface and/or reduce the splatter of water dropletes.

The baffle may have or may comprise a hydrophilic surface. The hydrophilic surface may comprise metal, ceramics or composites. The water that impinges on the hydrophilic surface forms a film and spreads out across the width of the baffle.

Alternatively, the baffle may have or may comprise a hydrophobic surface. The hydrophobic surface may comprise elastomer, e.g. silicone rubber, or polymer, e.g. polytetrafluoroethylene (PTFE) or polyimide. The water that impinges on the hydrophobic surface may run over the hydrophobic surface in a plurality of streams or rivulets.

The baffle may comprise one or more guiding structures configured to direct the water to the plate or steaming element. The one or more guiding structures may be configured to spread water over a larger width or area of the plate or steaming element. The one or more guiding structures may be selected from a group consisting of channels, grooves, slots and combinations thereof.

Preferably, the steaming element or plate has at least one channel extending between the first end and the second end. The at least one channel comprises a plurality of channels extending in parallel. If the steaming element or plate is inclined at an angle to the horizontal and when water is dispensed onto a heated flat plate or steaming element, the water forms a film and the direction of travel of the film relative to the plate or steaming element is determined by a combination of the surface tension of the water and gravity. The effect of surface tension can cause the water to migrate transversely across the plate or element's surface so that separate rivulets gather and form a thicker film. The presence of channels prevents the water from migrating transversely across the plate or element's surface as the surface tension effect is insufficient to cause the water to escape the channel; the water is instead caused by gravity to travel down the channel and form a thinner film which will evaporate more quickly and use less energy than if a thicker film is allowed to form.

Furthermore, the increased rate of evaporation means that the distance between the upper end and the lower end of the heated plate or element can be reduced for any given quantity of water dispensed. A steam promoter (a coating or a separate mesh attached) may be provided on the steaming element to enhance steaming effectiveness.

Preferably, according to the present invention there is provided a device for generating steam as described herein. The device may include a steam generator. A steam generator may include the steaming element. The steam generator may further include the baffle. The steam generator may also include the heating element. The steam generator may further include the water inlet arrangement.

Preferably, according to the present invention, there is provided a steamer appliance as described above comprising a water pump to deliver water to said water inlet arrangement, and a control unit for controlling the water flow rate delivered to the water inlet arrangement in dependence on said predetermined temperature. The appliance may also comprise a reservoir or tank for storing water before it is delivered to the water inlet arrangement. The water may be filtered or pre-treated prior to be dispensed on to the steaming element.

According to another aspect of the invention there is provided, a method of generating steam. The method may comprise heating a steaming element to a predetermined temperature being at least above water evaporation temperature. The method may further comprise dispensing water on a baffle, the baffle configured to direct the water towards a surface of the steaming element. The method may further comprisedispensing water from the baffle onto the steaming element to flow along the surface of the steaming element for generating steam.

The steaming element may be a plate. The plate may define or have a first end and a second end.

The plate may be inclined at an angle (AO) compared to the horizontal direction (H). The first end may be the lower end and the second end may be the upper end.

According to yet another aspect of the invention there is provided, a method of collecting scale in a device for generating steam. The method may comprise heating steaming element or a plate to a predetermined temperature being at least above water evaporation temperature, the steaming element or plate defining a first end and a second end. The method may further comprise dispensing water on a baffle, the baffle configured to direct the water to the steaming element or plate for generating steam. The method may additionally comprise collecting in a container or region any scale falling down from the steaming element or plate, the container or region comprising a bottom surface portion extending at least below the first end (i.e. lower end).

Preferably, the container is being disposed adjacent to said steaming element or plate. BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

FIG. 1 shows a cross-sectional side view of a device for generating steam according to an embodiment of the present invention;

FIG. 2A shows a cross-sectional side view of a device for generating steam according to another embodiment of the present invention;

FIG. 2B shows the perspective view of the device illustrated in FIG. 2A;

FIG. 3 A shows the baffle in contact with the plate according to one embodiment;

FIG. 3B shows the baffle spaced apart from the plate according to another embodiment;

FIG. 4A shows a baffle with an overhanging directing structure according to another embodiment when the device is in a tilted position during use; FIG. 4B shows the baffle when the device is in a horizontal position during use;

FIG. 5 shows a perspective view of yet another embodiment of the device; FIG. 6 shows a flow diagram according to a further aspect of the present invention; and

FIG. 7 is a flow diagram showing yet another aspect of the invention of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS FIG. 1 shows a cross-sectional side view of a device (1) for generating steam according to an embodiment of the present invention. The device (1) comprises a steaming element (2) forming a surface (3) for steaming water. The device (1) may further comprise a heating element (4) to heat the steaming element (2) to a predetermined temperature being at least above water evaporation temperature. The device (1) may also include a water inlet arrangement (5) for dispensing water. The device may additionally include a baffle (6) configured to receive the water dispensed by the water inlet arrangement (5). The baffle (6) may be further configured to direct the water to the steaming element (2).

In other words, the device (1) may include a steaming element (2) with a surface (3). Water is introduced to the plate (2) from a water inlet arrangement (5) via a baffle (6). The steaming element (2) may be heated to a suitable temperature by the heating element (4) for steaming the water.

The baffle (6) may help to spread the water out over a large width (or area) across the baffle (6) to enable water delivery on to the steaming surface (3) across the width (or area). As the water is spread over a larger width or area, the surface (3) for steaming water may be kept shorter, resulting in a more compact device. The baffle may be a splash plate.

The water evaporation temperature may be from about 95 to 105 °C, e.g. about 100 °C. The water inlet arrangement may comprise one or more water inlets for dispensing water onto the baffle. The water inlets arrangement may comprise one or more jet nozzles.

The water may be directed by the baffle (6) to the surface (3) of the steaming element (2). The steaming element (2) may be inclined at an angle (AO) compared to the horizontal direction (H) to define a lower end (7a) and an upper end (7b). For instance, the plate (2) may be inclined at least 45 degrees from the horizontal. However, it may also be envisioned that the steaming element (2) or/and the surface (3) of the steaming element (2) is parallel to the horizontal direction (H). The surface (3) may be a planar surface. The lower end (7a) may be referred to as a first end and the upper end (7b) may be referred to as a second end.

The steaming element (2) may be a plate as shown in FIG. 1. However, it may also be envisioned that the steaming element (2) may be a plate with a raised surface (3) or may be any structure that is suitable for heating and steaming water.

The steaming element (2) provides the above mentioned heated surface (3) onto which water is deposited when the device (1) is in operation. Scale formed on the steaming element (2) is broken up by the process of flaking. Flakes of scale are caused to migrate down the steaming element's (2) incline or slope. The device (1) may further comprises a container or region (not shown in FIG. 1) for collecting the flakes of scale. The container or region may be disposed adjacent to said steaming element (2).

If the steaming element (2) is an inclined plate, scale formed on the plate (2) travels down towards the lower end (7a). The container or region may be disposed beow the lower end (7a). The container may comprise a bottom surface portion extending below said lower end. The bottom surface portion may comprise a horizontal surface portion being lower than said lower end.

Preferably, there maye be provided a plurality of plates which surround the container or region. The container or region may be formed integrally with the plate or steaming element (2).

The container may comprise a plurality of walls with a detachable opening formed in at least one of the walls to access an inside part of the container.

The baffle (6) may be referred to as a splash plate. The baffle (6) may be any structure that is configured to receive water from the water inlet arrangement (5) and further configured to direct the received water to the steaming element (2). As shown in FIG. 1, the baffle (6) may have an edge (8a) spaced at a predetermined distance from the surface (3). The edge (8a) may be proximate to the plate (2). The predetermined distance may be for instance any value between about 0.1 cm to about 5 cm, e.g. about 0.1 cm to about 2 cm. However, it may also be envisioned that the baffle (6) is in contact with the surface (3), i.e. the edge (8a) is in contact with the surface (3). The baffle (6) may be in contact or nearly in contact with the surface (3) or/and steaming element (2) such that water flowing down forms a nearly continuous film over the baffle (6) and the surface (3) / steaming element (2).

The baffle (6) may have a further edge (8b) that is distal from the plate (2). The baffle (6) may be inclined at an angle (B0) to the horizontal. The angle (AO) may be negative and the angle (BO) may be positive with respect to the horizontal line H. The angle (BO) may be substantially of a large value. The angle (BO) may be obtuse. The angle (AO) may be of a smaller value than angle (BO). The angle (AO) may be acute.

The edge (8a) may have a serrated profile (e.g. saw-tooth-like) or may be smooth or may have a wavy pattern.

The baffle (6) may comprise one or more guiding structures (not shown in FIG. 1) configured to direct the water to the plate or steaming element (2). The one or more guiding structures may be configured to spread water over a larger width or area of the plate or steaming element (2). The one or more guiding structures may be selected from a group consisting of channels, grooves, slots and combinations thereof. The guiding structures may be arranged on the surface of the baffle (6). Additionally or alternatively, the guiding structures may be on or near from (i.e. within a predetermined distance) the edge (8a) of the bafffle (6).

The baffle (6) may have a hydrophilic surface. The hydrophilic surface may comprise metal or ceramics. The baffle (6) may also comprise metal or ceramics so the surface of the baffle (6) is hydrophilic. The water that impinges on the hydrophilic surface spreads out across the width of the baffle (6) to form a thin film. Subsequently, the thin film is directed onto the steaming element (2) The baffle (6) may have an edge having a serrated profile to spread the water across the width of the steaming element (2).

Alternatively, the baffle (6) may have or may comprise a hydrophobic surface.

The hydrophobic surface may comprise elastomer, e.g. silicone rubber, or polymer, e.g. polytetrafluoroethylene (PTFE) or polyimide. The baffle (6) may comprise elastomer or polymer so that the surface of the baffle (6) is hydrophobic. The water that impinges on the hydrophobic surface may run through the hydrophobic surface in a plurality of streams or rivulets. The hydrophobic surface allows the streams or rivulets of water to pass through quickly.

The steaming element or plate (2) may be provided with at least one channel (not shown in FIG. 1). The at least one channel may extend between the first end (7a) and the second end (7b). The at least one channel may comprise a plurality of channels. If the steaming element or plate (2) is inclined at an angle to the horizontal and when water is dispensed onto a heated flat plate or steaming element (2), the water forms a film and the direction and speed of travel of the film relative to the plate or steaming element (2) is determined by a combination of the surface tension of the water and gravity. The effect of surface tension can cause the water to migrate transversely across the plate or element's surface (3) so that separate rivulets gather and form a thicker film. The presence of channels prevents the water from migrating transversely across the plate or element's surface as the surface tension effect is insufficient to cause the water to escape the channel; the water is instead caused by gravity to travel down the channel and form a thinner film which will evaporate more quickly and use less energy than if a thicker film is allowed to form.

Furthermore, the increased rate of evaporation means that the distance between the upper end (7b) and the lower end (7a) of the heated plate or element (3) can be reduced for any given quantity of water dispensed. Additionally, the surface of the plate or element (3) may be provided with protruding features or depressions to increase the contact area with water.

FIG. 2A shows a cross-sectional side view of a device (1) for generating steam according to another embodiment of the present invention and like features in this embodiment retain the same reference numerals. FIG. 2B shows the perspective view of the device (1) illustrated in FIG. 2A. As in the above embodiment, the device (1) comprises a plate (2) forming a surface (3) for steaming water. The device (1) may further comprise a heating element (4) to heat the plate (2) to a predetermined temperature being at least above water evaporation temperature. The device (1) may also include a water inlet arrangement (5), such as one or more jet nozzles, for dispensing water. The device may additionally include a baffle (6) configured to receive the water dispensed by the water inlet arrangement (5). The baffle (6) may be further configured to direct the water to the plate (2).

Further, the device comprises a directing structure (9) configured to direct water back-scattered by the baffle (6) to the plate (2). The directing structure (9) helps direct back-scattered water droplets due to inpringement of the water jet on the baffle (6). The water droplets that are back-scattered would be caught by the directing structure (9) and be directed by the directing structure (9) onto the surface (3) of the plate (2).

The directing structure (9) may be part of the baffle (9). The directing structure (9) may extend from the baffle (6) so that the directing structure (9) overhangs the baffle (6). The directing structure (9) and the baffle (6) may form a continuous, integrated structure. Alternatively, the baffle (9) may be a structure separate from the directing structure (9). The directing structure (9) may have an edge (10) having a serrated profile. The edge having the serrated profile may be a free edge. The edge of the directing structure may directly be above the free edge of the baffle.

Preferably, the directing structure (9) comprises an opening (1 1) configured to allow passage of the water from the water inlet arrangement (5) onto the baffle (6). The water dispensed by the water inlet arrangement (5) may pass through the opening (1 1) without obstruction to the baffle (6) while the directing structure (9) may help direct back-scattered water droplets due to inpringement of the water jet on the baffle (6) back to the plate (2). The directing structure (9) and the baffle (6) may form a folded over design with the opening (1 1) for passage of the water jet and a partially enclosed space to help contain water that is back- scattered upon impingement onto the baffle (6).

L, LI and L2 in FIG. 2A represent possible flows of water. The water

(represented by L) dispensed by the water inlet arrangement (5) will pass through the opening (1 1) onto the baffle (6). On hitting the baffle (6), some water will flow along the baffle (6) onto plate (2) (represented by L2). Some water droplets (represented by LI) may be backscattered. The water droplets may fall onto overhanging directing structure (9) and be directed to baffle (6) and/or plate (2). The surface (3) of plate (2) is heated by heater (4), resulting in generation of steam. As shown in FIG. 2A, baffle (6) may be spaced at a predetermined distance from the planar surface. The predetermined disance may be for instance any value between about 0.1 cm to about 5 cm, e.g. about 0.1 cm to about 2 cm.

In FIG. 2A and FIG. 2B, the water inlet arrangement (5) does not pass through the opening (1 1). The water inlet arrangement (5) and the baffle (6) are on opposing sides of the opening (1 1). However, it may also be envisioned that the water inlet arrangement or jet nozzle (5) may pass through the opening (1 1). The opening (1 1) may be circular or semicircular or may be any suitable shape. The opening (1 1) may be a V-shaped or U-shaped notch extending from edge (10).

FIG. 3 A shows the baffle (6) in contact with the plate (2) according to one embodiment. The plate (2) may be perpendicular to the baffle (6). As seen from FIG. 3A, water running down baffle (6) is directly received by surface (3) of plate (2). FIG. 3B shows the baffle (6) spaced apart from the plate (2) according to another embodiment. The water film forms droplets of water due to the surface tension effect before falling off from the edge (8a) of the baffle (6). In both FIGS. 3 A and 3B, water from the jet nozzle (5) is dispensed onto the baffle (6) before being directed by the baffle (6) to the steaming surface (3) of the plate (2). FIG. 4A shows the baffle (6) with an overhanging directing structure (9) (i.e. a folded-over design) according to another embodiment. As shown in FIG. 4A, when the device (1) is in a tilted position during use, the directing structure may still be able to spread water sufficiently across the width of the steaming surface. FIG. 4B shows the baffle (6) when the device (1) is placed in a horizontal position during use. The directing structures (9) in both FIGS. 4A and 4B are able to spread water sufficiently across the width of the steaming surface. The baffle (6) has an edge (8a), which may be provided with a serrated profile (saw-tooth-like edges). The serrated profile allows the more uniform delivery of water by the baffle (6) to the steaming element (2), regardless of whether the device is in a horizontal or tilted position. The directing structure (9) also has an edge (10), which may be provided with a serrated profile (saw- tooth-like edges). The directing structure (9) includes an opening or hole (1 1) in which the jet nozzle (5) passes through. The directing structure (9) may help reduce back-scatter of water droplets due to impingement of water jet on the baffle (6) and help increase efficiency of directing water onto the steaming element (2).

FIG. 5 shows a perspective view of yet another embodiment of the device (1). Like features in this embodiment retain the same reference numerals. FIG. 5 shows a steaming element (2) having a surface (3) for steaming water. As shown in FIG. 5, the steaming element (2) may have a raised profile including the surface (3). The device further comprises a heating element (not shown in FIG. 5) to heat the steaming element (2) to a predetermined temperature being at least above water evaporation temperature. The device

(1) may also comprise a water inlet arrangement (5) for dispensing water. The device (1) further comprises a baffle (6) configured to receive the water dispensed by the water inlet arrangement (5), said baffle (6) further configured to direct the water to the steaming element (2).

A directing structure (9) extends from the baffle (6) and overhangs the baffle (6). The directing structure (9) may have an opening (1 1). Water is dispensed by the water inlet arrangement (5) through the opening (1 1) onto the baffle (6). As shown in FIG. 5 , the surface (3) may be horizontal. The steaming element

(2) may be a plate with a raised surface (3) in the middle of the plate. It may be envisioned that the steaming element (2) may be of any other suitable shapes. The steaming element (2) may be any structure with a surface (3) for heating and steaming water. As shown in FIG. 5, an inclined slope (12) may extend from the raised surface (3) to a planar lower surface (13). Lower surface (13) surrounds the raised surface (3). Water flows from the baffle (6) onto the surface (3) for steaming. Unevaporated water may further flow down the inclined slope (12) surrounding the raised surface (3) onto lower surface (13). The scale particles formed may be carried down along the inclined slope (12) with the unevaporated water.

A region or container (14) for collecting calc carried by the water may surround the lower surface (13). In one embodiment, the lower surface (13) may be the region or container (14) for collecting calc.

There may also be provided a steamer appliance including various features described herein and further comprising a water pump (e.g. electrical pump) to deliver water to said water inlet arrangement (5), and a control unit for controlling the water flow rate delivered to the water inlet arrangement (5) in dependence on said predetermined

temperature. The appliance may also comprise a reservoir or tank for storing water before it is delivered to the water inlet arrangement (5). The steamer appliance may be a steam iron or a garment steamer. Water may be delivered from the reservoir or tank to the surface (3) via the water inlet arrangement (5) and baffle (6) when the user activates a trigger of the water pump.

The steamer appliance may be of the instantaneous type. In other words, the steamer appliance may be configured to introduce water onto the heated surface (3) only when steam is needed.

FIG. 6 shows a flow diagram according to a further aspect of the present invention. The further aspect of the present invention may relate to a method of generating steam, said method comprising:

- in S 1 , heating a steaming element (2) to a predetermined temperature being at least above water evaporation temperature, and

- in S2, dispensing water on a baffle (6) , the baffle (6) configured to direct the water to a surface (3) of a steaming element (2) for generating steam.

The baffle (6) may help to spread the water out over a large width (or area) across the baffle (6) to enable water delivery on to the steaming surface (3) across the width (or area). As the water is spread over a larger width or area, the surface (3) for steaming water may be kept shorter, resulting in a more compact device. The method may be a method of generating steam using a device (1) according to any embodiment described herein.

The steaming element (2) may be a plate. The plate (2) may define or have a first end and a second end.

The plate (2) may be inclined at an angle (AO) compared to the horizontal direction (H). The first end (7a) may be the lower end and the second end (7b) may be the upper end.

The device (1) may further comprises a container or region (14) disposed adjacent to said plate (2). The container (14) may comprise a bottom surface portion extending at least below said lower end.

FIG. 7 is a flow diagram showing yet another aspect of the invention of the present invention. FIG. 7 shows a method of collecting scale in a device (1) for generating steam. The method may comprise:

- in Tl, heating a steaming element or a plate (2) to a predetermined temperature being at least above water evaporation temperature, the steaming element or plate (2) defining a first end (7a) and a second end (7b),

- in T2, dispensing water on a baffle (6), the baffle (6) configured to direct the water to the steaming element or plate (2) for generating steam,

- in T3, collecting in a container or a region (15) any scale falling down from the steaming element or plate (2), the container or region (15) comprising a bottom surface portion extending at least below the first end (7a).

The above embodiments as described are only illustrative, and not intended to limit the technique approaches of the present invention. Although the present invention is described in details referring to the preferable embodiments, those skilled in the art will understand that the technique approaches of the present invention can be modified or equally displaced without departing from the spirit and scope of the technique approaches of the present invention, which will also fall into the protective scope of the claims of the present invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1. A device (1) for generating steam, said device (1) comprising:

- a steaming element (2) having a surface (3) for steaming water,

- a heating element (4) to heat the steaming element (2) to a predetermined temperature being at least above water evaporation temperature,

- a water inlet arrangement (5) for dispensing water, and

- a baffle (6) configured to receive the water dispensed by the water inlet arrangement (5), said baffle (6) further configured to direct the water to the steaming element (2),

wherein the surface (3) for steaming water extends below the baffle (6) such that water flows from the baffle (6) onto the surface (3) of the steaming element (2), and wherein the steaming element (2) is configured such that water flows downwardly over the steaming element (2) to be evaporated.

2. The device (1) of claim 1, wherein the steaming element (2) is a plate being inclined at an angle (AO) compared to the horizontal direction (H) to define an upper end (7b) and a lower end (7a).

3. The device (1) of claim 2, further comprising a container (14), the container (14) comprising a bottom surface portion extending below said lower end.

4. The device (1) of any of the preceding claims, wherein the baffle (6) has an edge (8a) in contact with the surface (3).

5. The device (1) of any of claims 1 to 3, wherein the baffle (6) has an edge (8a) spaced at a predetermined distance from the surface (3).

6. The device (1) of claim 4 or claim 5, wherein the edge (8a) has a serrated profile.

7. The device (1) of any of the preceding claims, further comprising a directing structure (9) configured to direct water back-scattered by the baffle (6) to the steaming element (2).

8. The device (1) according to claim 7, wherein the directing structure (9) extends from the baffle (6) so that the directing structure (9) overhangs the baffle (6).

9. The device (1) according to claim 7 or claim 8, wherein the directing structure (9) comprises an opening (1 1) configured to allow passage of the water from the water inlet arrangement (5) onto the baffle (6).

10. The device (1) according to any of the preceding claims, wherein the baffle (6) comprises a hydrophilic surface.

1 1. The device (1) according to any of claims 1 to 9, wherein the baffle (6) comprises a hydrophobic surface.

12. The device (1) according to any of the preceding claims, wherein the baffle (6) comprises one or more guiding structures configured to direct the water to the steaming element.

13. The device (1) according to claim 12, wherein the one or more guiding structures are configured to spread water over a larger area of the steaming element (6).

14. A steamer appliance comprising the device (1) for generating steam according to any preceding claims.

15. A method of generating steam, said method comprising:

- heating a steaming element (2), having a steaming surface (3), to a predetermined temperature being at least above water evaporation temperature,

- dispensing water on a baffle (6),

- positioning the steaming element (2) so that the steaming surface (3) extends below the baffle (6) such that water flows from the baffle (6) onto the surface (3) of the steaming element (2), and so that water flows downwardly over the steaming element (2) to be evaporated.