WO2006040556A1

WO2006040556A1 - Steaming appliances comprising water-treatment means

Info

Publication number: WO2006040556A1
Application number: PCT/GB2005/003931
Authority: WO
Inventors: Christina Goodrick-Meech; Suzie Patel
Original assignee: Kenwood Limited
Priority date: 2004-10-13
Filing date: 2005-10-12
Publication date: 2006-04-20

Abstract

Described are steaming appliances usable, for example, for cooking, ironing and cleaning, especially in the home. Such a steaming appliance (1, 21) comprises an electrically powered heater (5, 28) arranged to heat water, thereby generating steam to be used by or in the appliance, and includes a water-treatment device (7, 30) for treating the water in order to reduce the content of unwanted materials therein. The water-treatment device is exposed to the water and an indicator (12, 34) is provided for indicating a need for attention to the device, as a result of a predetermined degree of usage of the appliance and/or the time elapsed since either the installation of the device or its last inspection. By this means, a user of the appliance is made aware of the need to refill or replace spent treatment cartridges (17, 30), or to cleanse or otherwise care for the water-treatment: device to thereby ensure that the water is at all times subject to effective treatment.

Description

STEAMING APPLIANCES COMPRISING WATER-TREATMENT MEANS

This invention relates to steaming appliances usable, for example, for cooking, ironing and cleaning, and it relates especially though not exclusively to such apparatus intended for use in the home.

Whilst it has long been the practice for certain electrically heated domestic smoothing irons to contain a reservoir for water that can be locally boiled in the iron under user control, to generate steam for direct application to the clothing or other materials being pressed, more recent developments have moved towards the use of so-called "steam stations", wherein a base unit that is separate from a smoothing iron contains a steam chamber used to generate steam for application to the iron by way of suitable tubing; the iron having a switch or other control device, operable by the user, to select whether or not steam is applied to the materials being pressed. Such arrangements have the advantage, inter alia, that greater quantities of steam can be made available for chosen pressing operations, as the reservoirs used in the irons themselves are necessarily of limited capacity.

Further developments to steam stations have resulted in improvements such as the use of water reservoirs which can be detached from the base unit to facilitate filling, and the use of reservoirs, or communicating vessels, that are constructed to make the water level readily visible, so that a user knows when to top up the base unit with water. It is also known to construct the base unit so as to minimise the amounts of water boiled at any time, with economy and energy conservation in view. Such steam stations are known, for example, from US 6615515-B1 and US 6640472-B1.

A recent innovation, described in UK patent application No. GB0413900.2 and assigned to the present applicant, provides for the steam generated in the steam station to be readily usable for purposes other than ironing and, in one particular embodiment described in that application, there is provided an outlet additional to that which feeds steam to the iron, into which a tubular connection can be plugged in order to apply the steam to a choice of head devices adapted for cleaning or other purposes.

Currently, however, despite all of their sophistication, and despite the fact that steam irons as such have routinely been provided with facilities for water treatment aimed at softening the water used therein, steam stations can exhibit operational difficulties, resulting, for example, in tendencies for the heater efficiency to reduce over time, due at least in part to scale formation, and for water-borne scale to clog, or otherwise adversely affect the regular flow of steam from, orifices at the iron and/or at the heads used for cleaning and/or other purposes.

This invention also relates to food steamers; especially, though not exclusively, tiered steamer systems, wherein a plurality of food support trays is stacked within an enclosure supported on a base containing a water heater, and arranged such that food on each tray can be subjected to steam issuing from the heater. It is well accepted that steaming is a healthy, and tasty way of preparing certain foods, and current interest in healthy eating has promoted significant interest in domestic appliances of this kind. There are several such appliances available on the market, and most operate efficiently and are user-friendly. However, certain difficulties can arise in operation of such appliances, including tendencies for the heater efficiency to reduce over time, due at least in part to scale formation, and for water-borne chemicals, such as chlorine, to taint the flavour of food steamed therein.

It is an object of this invention to address such difficulties and, in accordance with one example of the invention there is provided a steaming appliance comprising a water reservoir in communication with an electrically operated heater arranged to generate steam; the appliance further comprising water-treatment means disposed to treat water to be heated in the heater, such as to reduce the content of unwanted materials therein, wherein the water-treatment means comprises a water-treatment device housed in fluid communication with water added to said reservoir; and wherein indicator means are provided for indicating a need for attention to the water-treatment device, as a result of usage of the appliance and/or effluxion of time.

By this means, a user of the appliance is made aware of the need to refill or replace spent filter cartridges, or to cleanse or otherwise care for the water-treatment device to thereby ensure that the water is at all times subject to effective filtration. The indicator means may take any convenient form, such as a colour change associated with a filtration medium, or an additive thereto, incorporated into the water-treatment device, for example in the form of a cartridge; such an arrangement requiring part at least of a readily visible portion of the cartridge to be sufficiently transparent or translucent to permit a user to observe the colour change.

An alternative, or additional, indicator means may respond to motion of a part of the appliance that is opened, or otherwise moved, when water is to be added to the reservoir, or the appliance otherwise readied for operation.

Some preferred embodiments of the invention, may comprise a ratchet mechanism linking the motion of said appliance part to a progressively mobile mechanical indicator; for example, one of the same general kind as that disclosed in EP-0756583-B1 and EP-0861809-B1.

It is further preferred, however, that electrical signals indicative of motion of the said part are generated, and supplied to an electronic indicating device, such as a liquid crystal display (LCD) device, and/or one or more light-emitting diodes (LEDs). Microprocessor devices may be employed in known manner to drive such electronic indicating devices.

A particularly preferred embodiment of the invention detects the switching on of power to the appliance as a primary indication of usage, whereby electrical signals indicative of such switching operations are generated and an electronic display indicative of usage of the appliance is derived therefrom.

In a further preferred embodiment, an electrical indication of usage is derived by means of a reed switch or other sensor located so as to respond to a component, such as a magnet, contained in or associated with a tubular connector that is connectable to an outlet of the steam generator to convey the steam therefrom to a remote location, such as an iron or a cleaning head.

In all embodiments of the invention utilising electrical or electronic indicator means, such electrical power as may be required to drive components such as sensors, displays and microprocessors may be derived from the mains electricity supply (suitably processed as necessary), or any or all such components may be battery powered. Preferably, the power is primarily derived from the mains supply, but is backed up by battery in case of mains failure, or to allow for prolonged periods of non-use.

In all embodiments, the water reservoir may be supplied with water either directly through a filler orifice or indirectly by way of a removable tank, which may be carried to a faucet for filling. If a removable tank is used, it is preferably provided with means whereby the water level therein is rendered readily visible to a user. Such means may comprise the use of a transparent or translucent medium for part of the tank itself, or the incorporation of one or more windows through which the water level can be discerned. The tank and/or the window may advantageously bear capacity markings to enable a user to readily decide when the tank should be filled or topped up with water.

In order that the invention may be clearly understood and readily carried into effect, certain embodiments thereof will now be described with reference to the accompanying drawings, of which:

Figure 1 shows, in side elevation and in part cross-sectional view, a steam station in accordance with one example of the invention; and

Figure 2 shows, in similar view to Figure 1, the base part of a steam station in accordance with another example of the invention.

Figure 3 shows, in side elevation and in part cross-sectional view, a food steamer in accordance with one example of the invention; and

Figure 4 shows, in similar view to Figure 3, the base part of a food steamer in accordance with another example of the invention.

Referring now to Figure 1 , there is shown a steam station in accordance with one example of the invention. It will be appreciated that, since many components of the steam station illustrated are conventional, such components will either not be referenced at all or, if mentioned, will not be described in detail.

The steam station's base unit is shown generally at 1, and comprises a casing 2 which houses the principal components of the steam station, as will be described. Mounted within the casing 2 are primary and secondary water reservoirs 3 and 4 respectively, and an electrically operated heater 5 comprising a tubular, through-flow water heater of known kind. The heater 5 is plumbed into fluid communication with the reservoir 4 and arranged to heat water supplied to it from the reservoir 3 in order to generate steam, which issues from a steam outlet 6.

If desired, and as is known, the steam outlet 6 may be coupled by way of a tubular, steam-handling connection (not shown) to an iron or to a cleaning head, or a steam-control head used for an alternative purpose. The casing 2 may usefully, as indicated previously, be provided with more than one steam outlet, so that a first tubular conduit, used for ironing, can be attached to a first outlet, and a second tubular conduit, used for cleaning and/or other purposes, can be attached to a second steam outlet. In such an arrangement, it is sometimes preferred for the first outlet, at least, to be provided with a manually operable controller to enable a user to adjust the volume of steam issuing from the respective outlet.

In any event, the steam station of Figure 1 further comprises a water treatment means disposed to treat water to be heated in the heater.

The water treatment means in this example comprises a cartridge 7 containing a water treatment medium intended to reduce the content of scale-producing materials therein. In this example, the filter cartridge 7 is positioned such that its lid 8 which, in known manner, is configured to comprise a water inlet to the cartridge, is disposed at a low point of the primary water reservoir 3. Water filtered through the water treatment medium within the cartridge 7 fills the secondary reservoir 4, which is connected by a water outlet tube 9 to the inlet of the heater 5.

It will be observed that the water outlet tube 9 is plumbed to an upper region of the reservoir 4. This configuration is used particularly for cartridges whose water-filtration media are intended to be kept constantly wet. For alternative media, the plumbing of the tube 9 may differ.

A user of the steam station 1 can add water to the primary reservoir 3 by way of a fill aperture 10 provided in the. casing 2 and closed by way of a filler lid 11.

It will be appreciated that the cartridge 7 is mounted so as to be readily removable from the steam station for replacement or for recharging of the water-treatment medium therein and accordingly, in this embodiment of the invention, the dimensions of the fill aperture 10 are designed to accommodate access to, and removal of, the cartridge. If preferred, access to the cartridge may be gained by other means. For example, a part of the top cover of the casing 2 may be hinged, and thus liftable to expose the cartridge.

In this respect, it is of importance for a user to know when to replace or recharge a filter cartridge, in order to ensure that an effective filter medium is at all times exposed to the water, and thus an indication of actual or forthcoming expiry of the useful life of the filter medium, as a result of usage and/or effluxion of time, is provided. Such an indication may take any convenient form, such as a colour change associated with the medium itself, or an additive thereto; such an arrangement requiring part at least of the cartridge to be sufficiently transparent or translucent, and for the casing 2 to be provided with a window, or some other means whereby the aforementioned part of the cartridge is made readily visible, to permit a user to observe the colour change.

Alternatively or additionally, the indication may be provided by a specific indicator means located on the casing 2 of the steam station. Such an indicator means may respond, for example, to motion of a part of the steam station (such as the lid 11 covering the water-fill aperture 10) that is opened, or otherwise moved, when water is to be added to the reservoir, or when the steam station is otherwise readied for operation. In such circumstances, the indicator means may comprise a ratchet mechanism linking the motion of said steam station part to a progressively mobile mechanical indicator; for example, one of the same general kind as that disclosed in EP-0756583-B1 and EP-0861809-B1.

In the embodiment of the invention shown in Figure 1, however, electrical signals indicative of motion of the said part, or the fitment of a tubular connection to an outlet of the casing, are generated by any convenient means, such as one or more magnetic reed switches which are not shown, but are well known in the art, and supplied to en electronic indicating device, such as a liquid crystal display (LCD) device 12, and/or one or more light-emitting diodes (LEDs). Microprocessor devices may be employed in known manner to process the electrical signals and to drive such electronic indicating devices. Radio-frequency identifying devices (RFIDs) can be used instead of or in addition to reed switches if desired.

Instead of generating electrical signals in response to the motion of said part of the steam station, or the attachment of a tubular connection thereto, it is preferable in some respects to detect the switching on of electrical power to the steam station as a primary indication of usage, whereby electrical signals indicative of such switching operations are generated and the indication provided by the electronic display 12, indicative of usage of the steam station, and thus the likely condition of the water treatment medium, is derived therefrom.

However the signals are generated, a preferred configuration is for the display 12 to show an accumulating count representing the actual number of uses of the steam station, or a decrementing count, indicating how many uses can be tolerated before replacement of the cartridge is advisable. In addition, a day-by-day background count, purely indicative of elapsed time since the previous installation of a cartridge, is preferably performed by the microprocessor, and used to display, either by means of the LCD itself, or by illumination of an adjacent LED, when the cartridge fill has time-expired. In some embodiments, it may be preferred to show the elapsed time count as the principal display and to use a usage-related count as a back-up. Clearly alternative or additional warnings, such as audible warnings, can be provided if preferred; any audible warning preferably (once having been actuated) being operative to sound each time the steam station is switched on until the cartridge is replaced. In this respect, the audible alarm may operate for a fixed time period and/or be capable of being switched off by means of a user-operated cancellation button, effective until the next switching-on of the steam station.

In the embodiment of the invention shown in Figure 2, wherein all components common to Figure 1 carry corresponding reference numbers, the secondary water reservoir 4 is supplied with water indirectly by way of a removable tank 13, which may be carried to a faucet for filling. If a removable tank such as 13 is used, it is preferably provided with means whereby the water level therein is rendered readily visible to a user. Such means may comprise the use of a transparent or translucent medium for part of the tank itself, or the incorporation of one or more windows through which the water level can be discerned. The tank and/or the window may advantageously bear capacity markings to enable a user to readily decide when the tank should be filled or topped up with water.

The water outlet tube 9 is, in this instance, plumbed in near the base of the secondary reservoir 4. If it is necessary to maintain the filter medium in cartridge 7 in a permanently wet condition, a weir arrangement is provided by a wall 14.

Referring now to Figure 3, there is shown a food steamer in accordance with another example of the invention. It will be appreciated that, since many components of the steamer illustrated are conventional, such components will either not be referenced at all or, if mentioned, will not be described in detail.

The steamer is shown generally at 21, and comprises at least one tray member, or basket, such as 22 for food to be steamed, supported within a casing 23 with a lid 24; the casing 23 being mounted on a base 25. Mounted within the base 25 are primary and secondary water reservoirs 26, 27 respectively, and an electrically operated heater 28 comprising a tubular, through-flow water heater of known kind. The heater 28 is plumbed into fluid communication with the reservoir 27 and arranged to heat water supplied to it from the reservoir in order to generate steam, which issues into the enclosure formed by the lidded casing 23 by way of a steam outlet 29.

In this example, three baskets such as 22 are provided for presenting food to be steamed, and these are supported in any convenient manner so that food placed thereon can be exposed to the steam. If desired, as is known, the steam outlet 29 may be coupled to a centrally located tube, or chimney, (not shown) extending upwardly within the casing 23 and configured to promote the supply of steam to the locations occupied by the baskets 22; the baskets being centrally apertured to accommodate the chimney.

In any event, the steamer of Figure 3 further comprises a water treatment means disposed to treat water to be heated in the heater. The water treatment means in this example comprises a cartridge 30 containing a water treatment medium intended to reduce the content of scale-producing and/or flavour-tainting materials therein. In this example, the filter cartridge 30 is positioned such that its lid 30a which, in known manner, is configured to comprise a water inlet to the cartridge, is disposed at a low point of the primary water reservoir 26. Water filtered through the water treatment medium within the cartridge 30 fills the secondary reservoir 27, which is connected by a water outlet tube 31 to the inlet of the heater 28.

As in the previously described embodiment, the water outlet tube 31 is plumbed to an upper region of the reservoir 27. This configuration is used particularly for cartridges whose water-filtration media are intended to be kept constantly wet. For alternative media, the plumbing of the tube 31 may differ.

A user of the steamer 21 can add water to the primary reservoir 26 by way of a fill aperture 32 provided in the base 25, and it is also preferable for the steamer to be configured such that condensate from the steaming operation is caught in a perforated tray member 33 and channelled therefrom into the primary reservoir 26 for re-cycling.

It will be appreciated that the cartridge 30 is mounted so as to be readily removable from the steamer for replacement or for recharging of the water-treatment medium therein. As with the previously described embodiments of the invention, it is of importance for a user to know when to replace or recharge a filter cartridge, in order to ensure that an effective filter medium is at all times exposed to the water, and thus an indication of actual or forthcoming expiry of the useful life of the filter medium, as a result of usage and/or effluxion of time, is provided.

Such an indication, as with the steam station described above with reference to Figures 1 and 2, may take any convenient form, such as a colour change associated with the medium itself, or an additive thereto; such an arrangement requiring part at least of a readily visible portion of the cartridge to be sufficiently transparent or translucent to permit a user to observe the colour change.

Alternatively or additionally, the indication may be provided by a specific indicator means located on the base 25 of the steamer. Such an indicator means may respond, for example, to motion of a part of the steamer (such as a flap or lid (not shown) covering the water inlet 32) that is opened, or otherwise moved, when water is to be added to the reservoir, or when the steamer is otherwise readied for operation. In such circumstances, the indicator means may comprise a ratchet mechanism linking the motion of said steamer part to a progressively mobile mechanical indicator; for example, one of the same general kind as that disclosed in EP-0756583-B1 and EP-0861809-B1.

In the embodiment of the invention shown in Figure 3, however, electrical signals indicative of motion of the said part are generated by any convenient means, such as RFIDs and/or one or more magnetic reed switches which are not shown, but are well known in the art, and supplied to en electronic indicating device, such as a liquid crystal display (LCD) device 34, and/or one or more light-emitting diodes (LEDs). Microprocessor devices may be employed in known manner to process the electrical signals and to drive such electronic indicating devices.

Instead of generating electrical signals in response to the motion of said part of the steamer, it is preferable in some applications to detect the switching on of electrical power to the steamer as a primary indication of usage, whereby electrical signals indicative of such switching operations are generated and the indication provided by the electronic display 34, indicative of usage of the steamer, and thus the likely condition of the water treatment medium, is derived therefrom.

However the signals are generated, a preferred configuration is for the display 34 to show an accumulating count representing the actual number of uses of the steamer, or a decrementing count, indicating how many uses can be tolerated before replacement of the cartridge is advisable. In addition, a day-by-day background count, purely indicative of elapsed time since the previous installation of a cartridge, is preferably performed by the microprocessor, and used to display, either by means of the LCD itself, or by illumination of an adjacent LED, when the cartridge fill has time-expired. In some embodiments, it may be preferred to show the elapsed time count as the principal display and to use a usage-related count as a back-up. Clearly alternative or additional warnings, such as audible warnings, can be provided if preferred; any audible warning preferably (once having been actuated) being operative to sound each time the steamer is switched on until the cartridge is replaced. In this respect, the audible alarm may operate for a fixed time period and/or be capable of being switched off by means of a user-operated cancellation button, effective until the next switching-on of the steamer.

In the embodiment of the invention shown in Figure 4, wherein all components common to Figure 3 carry corresponding reference numbers, the secondary water reservoir 27 is supplied with water indirectly by way of a removable tank 35, which may be carried to a water tap for filling. If a removable tank such as 35 is used, it is preferably provided with means whereby the water level therein is rendered readily visible to a user. Such means may comprise the use of a transparent or translucent medium for part of the tank itself, or the incorporation of one or more windows through which the water level can be discerned. The tank and/or the window may advantageously bear capacity markings to enable a user to readily decide when the tank should be filled or topped up with water.

The water outlet tube 31 is, in this instance, plumbed in near the base of the secondary reservoir 27. If it is necessary to maintain the filter medium in cartridge 30 in a permanently wet condition, a weir arrangement is provided by a wall 36. In all embodiments of the invention utilising . electrical or electronic indicator means, such electrical power as may be required to drive components such as sensors, displays and microprocessors may be derived from the mains electricity supply (suitably processed as necessary to effect functions such as voltage reduction and stabilisation), or any or all such components may be battery powered. Preferably, the power is primarily derived from the mains supply, but is backed up by battery in case of mains failure, or to allow for prolonged periods of non- use.

In general terms, it will be appreciated that the relative dimensions of the primary and secondary water reservoirs, or of the tank and the secondary reservoir in the case of the embodiments described with reference to Figures 2 and 4, can be adjusted as required to suit any set of operational and/or design criteria for the steamer, and no criticality is ascribed thereto. Furthermore, there are many electronic and mechanically driven displays known in the art of water-filter usage indication (for example, from the art of jug-based water filter units used in the home) and it is not intended to exclude any viable display technique from the scope of this invention.

Moreover, it will be readily appreciated that any convenient electrically- powered heating device or arrangement may be used to heat the water in any embodiment of the invention.

It will further be appreciated that the invention is not limited to the utilisation of water treatment devices based on filter cartridges containing filter media. It is also applicable, for example, to water treatment devices utilising scale inhibitors comprising meshes or other structures and/or magnetic or electromagnetic components, all of which operate in a fundamentally different manner to conventional cartridge- based filters, but which still require attention at intervals to ensure that they are clean and functional.

Claims

CLAIMS:

1. A steaming appliance comprising a water reservoir in communication with an electrically operated heater arranged to generate steam; the appliance further comprising water-treatment means disposed to treat water to be heated in the heater, such as to reduce the content of unwanted materials therein, wherein the water-treatment means comprises a water-treatment device housed in fluid communication with water added to said reservoir; and wherein indicator means are provided for indicating a need for attention to the water-treatment device, as a result of usage of the appliance and/or effluxion of time.

2. An appliance according to claim 1 wherein water is constrained to flow through the water-treatment device on its passage to said reservoir.

3. An appliance according to claim 1 or claim 2, wherein the water- treatment device is mounted so as to be readily removable from the steam station for replacement or recharging.

4. An appliance according to any preceding claim wherein said water-treatment device comprises a filter cartridge containing a filtration medium.

5. An appliance according to claim 4, wherein said indicator means comprises a colour change associated with the filtration medium itself, or an additive thereto, and wherein part at least of a readily visible portion of the cartridge is sufficiently transparent or translucent to permit a user to observe the colour change.

6. An appliance according to any preceding claim, wherein said indicator means is conditioned to respond to motion of a mobile part of the appliance that is opened, or otherwise moved, when water is to be added to the reservoir, or the appliance otherwise readied for operation.

7. An appliance according to claim 6, wherein said indicator means comprises a ratchet mechanism linking the motion of said mobile part to a progressively mobile mechanical indicator.

8. An appliance according to claim 6 or claim 7, further including means for generating electrical signals indicative of motion of the said mobile part, and for supplying said signals, or signals derived therefrom, to an electronic indicating device.

9. An appliance according to any preceding claim, comprising an outlet from said steam generator and further including means for generating electrical signals indicative of the presence of a component associated with a tubular connector that is connectable to said outlet to convey steam to a remote location, and for supplying said signals, or signals derived therefrom, to an electronic indicating device.

10. An appliance according to any preceding claim, further including means for generating electrical signals indicative of the switching on of power to the appliance, and for supplying said signals, or signals derived therefrom, to an electronic indicating device.

11. An appliance according to any of claims 8, 9 or 10, wherein said electronic indicating device comprises a liquid crystal display (LCD) device, and/or one or more light-emitting diodes (LEDs).

12. An appliance according to any of claims 8 to 11, further including a microprocessor device to drive said electronic indicating device.

13. An appliance according to any of claims 8 to 12, wherein electrical power required for said electronic indicating device is derived from the mains electricity supply.

14. An appliance according to any of claims 8 to 13, wherein said electronic indicating device is battery powered.

15. An appliance according to any preceding claim, wherein said water reservoir is supplied with water directly through a filler orifice.

16. An appliance according to any one of claims 1 to 14 wherein said water reservoir is supplied with water indirectly by way of a removable tank.

17. An appliance according to claim 16 wherein said tank is provided with means whereby the water level therein is rendered readily visible to a user.

18. An appliance according to any preceding claim, configured as a steam station.

19. An appliance according to any of claims 1 to 17, configured as a food steamer.