EP1922443B1 - Household appliance with an emitter for producing ultraviolet light - Google Patents

Abstract

The wash drum (1) of a horizontal axis front loading washing machine is rotatably mounted in a container (2) in which water and treatment agents are introduced through a dispenser (12) and emptied by a pump (6) close to which a UV radiation source (4) is mounted in the recirculation path (8) of the wash liquor. An additional UV source (3) disinfects the inside of the wash chamber when empty.

Description

The invention relates to a domestic appliance having a chamber which is adapted for treating a product with a liquid and a sump region, to which a pumping device for pumping liquid out of the chamber is connected, and a radiator for generating an ultraviolet light.

Such a household appliance goes out of the DE 43 42 049 C2 out. The household appliance described is a washing machine, which is set up for washing the material introduced according to a circulation process for the washing liquor used and has a storage unit for used rinse water. The radiator surrounds a conduit through which wash liquor is circulated, that is, pumped out of a sump area of the chamber and conveyed into a drum rotating in the chamber with the material to be treated. Ultraviolet light from the radiator impinges the wash liquor and destroys any bacteria and other microorganisms such as viruses, fungi and algae (all microorganisms hereafter called "germs") in the wash liquor. However, the spotlight is effective only as long as the washing lasts; it is not suitable for use against germs which, after the end of the washing and after removal of the washed product in the liquid used by the washing or rinsing, may still possibly form a residue of this liquid-containing chamber.

From the DE 32 32 057 A1 is a washing machine, in which a supply of ozone to eliminate unwanted germs is provided. Although ozone is indeed effective against such germs, its bleaching effect on colored textiles, its unpleasant odor, and its irritating effect on the human organism have not yet allowed its practical application.

In addition to these known washing machines, home appliances, in particular dishwashers, are known in which, following a rinsing process, machine components are present or provided for in any case Be dried facilities to prevent sticking and clumping of detergents, which are dosed for a subsequent rinsing process. For this purpose reference is made to the documents DE 36 06 053 C1 . WO 93/18701 A1 . DE 103 55 139 A1 . WO 03/071917 A2 . WO 2005/060813 A1 and WO 2005/060821 A1 ,

Starting from the cited prior art, the invention to be presented below is based on the object of further developing the known household appliance in such a way that the spread of germs is prevented which, without further action, after the treatment of the material and the removal of the treated material the home appliance in the still used by the liquid used for treating, could possibly form a residue of this liquid-containing chamber.

For this purpose, solutions have already been proposed in the prior art. So revealed JP 04 36 4825 A a household appliance with a radiator for generating UV light. This light source irradiates the entire interior of a dishwasher. These devices are known as sterilizers.

To achieve this object, a domestic appliance is provided with a chamber which is adapted for treating a product with a liquid and a sump region, to which a pumping device for pumping liquid out of the chamber is connected, and a radiator for generating an ultraviolet light, in which domestic appliance the radiator is set up to irradiate the sump area with the light. The radiator has a pivotable screen, which prevents that a light-sensitive part, in particular to be treated Good, is irradiated.

According to the invention, therefore, the irradiation is carried out exactly where it is to be expected mainly with a load of the household appliance by germs that could spread in a moisture left behind by a previous treatment process.

The emitter comprises, for example, a liquid-tight cylinder of quartz glass or suitable, permeable to ultraviolet radiation and correspondingly resistant plastic, in which the actual source of ultraviolet radiation is used.

Preferably, a radiator adapted to generate the light having a preferred wavelength of 253.7 nm as a wavelength spectrum centered around that wavelength.

That the radiator has a screen, which prevents a sensitive to the light part, in particular to be treated Good, irradiated, is particularly important if the appliance is a washing machine, because you usually do not want to suspend laundry ultraviolet radiation due to their bleaching effect. This screen is pivotable, for example, when it is not needed, to be pivoted into a treatment process not disturbing position.

Also preferred is a development of the domestic appliance, in which the pumping device has a drain line, and in which in the drain line, an additional radiator for generating an ultraviolet light and irradiating the drain line is arranged. Thus, treatment with ultraviolet radiation is extended beyond the sump area of the chamber, thus ensuring complete elimination of unwanted germs.

Particularly preferred is a domestic appliance, which additionally has a drying device, in particular a drying device comprising a fan for drying the chamber, so as to exclude that after a successful irradiation of the sump area immigrated germs find a particular moist environment in which they can spread. This drying device may more preferably comprise a heat source associated with the chamber for accelerating drying. In this case, with additional preference, the radiator itself can be the heat source; with equal preference may also or additionally be a heating element for heating the liquid for treating the material, the heat source - which comes in particular in a trained as a washing machine domestic appliance into consideration.

With further preference, a supply air duct for supplying dry air from an environment of the domestic appliance into the chamber as well as an exhaust duct for draining moist exhaust air from the chamber are provided in the drying device.

With a further preference, a sensor, in particular a moisture sensor, is provided in the household appliance for controlling the drying, wherein these control can be effected by a generally known and, in the present case, correspondingly improved control device to which the sensor is connected.

The household appliance according to the invention or one of its preferred developments just described is in particular designed as a washing machine for washing the goods. In this case, a rotatable drum for receiving the goods is arranged with further preference in the chamber.

Embodiments of the invention are described below with reference to the drawing.

The sole figure of the drawing shows a household appliance in the form of a washing machine. The depiction is schematic and symbolic in order to highlight the aspects that are of particular importance here.

The washing machine 18 for treating, namely washing, a product 20, represented here by two textile pieces 20, comprises a drum 1 for receiving these textile pieces 20, which drum 1 is suspended rotatably in a tub 2. The tub 2 is partially filled with a wash or rinse liquor to treat the product 20, as can be seen in the dashed and wavy line. This liquor fills the tub 2, starting from a sump area 19 to an appropriate height. If the liquor is removed from the tub 2, it remains moist in its lower area, here named and shown as the sump area 19; Under certain circumstances, a residue of the liquor may remain. For this reason, the swamp area 19 after completion of treatment of a material 20 provides a milieu which can favor the propagation of various microbial germs. In order to prevent such a spread, a radiator 3 for irradiating the sump region 19 with an ultraviolet light is provided in the sump region 19. Ultraviolet light is known to have a strong disinfecting effect and is therefore capable of effectively disinfecting the sump area 19.

The liquor passes from the sump region 19 via a drain line 17, in which a lint filter 5, an additional radiator 4 for disinfecting the drain line 17 with ultraviolet light and a pump 6 are arranged in succession. Behind the pump 6, the washing or rinsing eye passes through a corresponding switchable valve either to a drain hose 7 and there in a sewer network outside the washing machine 18, or via a recirculation line 8 in the drum 1 back. With help the circulation line 8, a washing process can be realized, in which the wash liquor is circulated by means of the pump 6 and the circulation line 8.

Via a fresh water inlet 13 and a fresh water line 15 together with a suitable, switchable valve arrangement, fresh water from a corresponding fresh water network outside the washing machine 18 can be supplied to the tub 2.

Ultraviolet light, which can be usefully used for disinfection, also has the property of exerting a strong bleaching action in a humid and oxygen-containing environment and also of attacking textile material. Thus, under certain circumstances, it may be necessary to shield corresponding sensitive parts, in particular laundry 20, from such light. For this purpose, the radiator 3 is provided with a pivotable screen 14 (shown only schematically). If after the completion of the washing process, the sump area 19 is disinfected by means of the radiator 3, the screen 14 can be pivoted so that the laundry 20 is shielded from the light. During a washing process, in which the radiator 3 is not used regularly, the screen 14 can be pivoted to a position in which it is as far as possible from the rotating drum 1 and thus does not interfere with the washing process.

In order to achieve effective drying of the sump region 19, a drying device 9, 10, 11, 12 comprising a supply air duct 9 for supplying dry air from an environment of the washing machine 18 into the chamber 2, and also an exhaust duct 10 for discharging moist exhaust air the chamber 2. To support a corresponding air circulation in the supply air duct 9, a fan 11 is provided. The supply air duct 9 brings the dry air expedient equal to the sump area 19; By contrast, the exhaust duct 10 is connected to a region of the chamber 2 away from the sump area 19. The exhaust duct 10 opens into exhaust openings 12, from which the exhaust air from the washing machine 18 also passes. These exhaust openings 12 are located for example in a detergent drawer, as it is commonly used for dosing detergent. In this way, the detergent drawer is dried and thus placed in a durable against the spread of germs safe state.

In addition, the radiator 3 can be advantageously used to dry the sump area 19 with the heat which it produces in addition to the light. This improves the stability of the sump region 19 against the spread of germs. In addition to the radiator 3, a heating rod 16 (which is always present in a conventional washing machine) (also indicated only schematically) can be used for heating the sump region 19 for the purpose of drying it.

The already mentioned screen 14 on the radiator 3 can also serve, in addition to shielding the sensitive material 20, to allow an operator to observe the radiation emanating from the radiator 3 by a conventional sight glass in a door of the tub 2. Since the Natronsilikatglas usually used in such a door is impermeable to ultraviolet radiation, damage to the operator is not to be feared. Finally, the screen can also be used to selectively guide the radiation from the radiator 3 to different subregions of the sump region 19. Within the scope of such a configuration, the emitter 3 itself does not always have to illuminate readily all subregions of the sump area 19 to be treated, which results in a certain degree of constructive freedom in the design of the washing machine 18.

The described disinfection and drying process in the washing machine 18 can be controlled by simple timing; In particular for the drying process, a control supported by a corresponding moisture sensor is also possible. Such a sensor can be mounted, for example, in the exhaust duct 10; If a predetermined limit value for the humidity of the exhaust air is reached during the drying process in the exhaust air duct 10, then the drying process can be ended.

LIST OF REFERENCE NUMBERS

1

drum

2

chamber

3

spotlight

4

Additional spotlight

5

lint filter

6

pump

7

drain hose

8th

circulation line

9

supply air duct

10

exhaust duct

11

fan

12

exhaust vent

13

Fresh water inlet

14

umbrella

15

Fresh water pipe

16

heater

17

drain line

18

household appliance

19

sump area

20

laundry

Claims (10)

1. Domestic appliance (18) with a chamber (2) equipped for treatment of stock (20) by a liquid, and a sump region (19) with which a pump device (6, 7, 17) for pumping liquid out of the chamber (2) is connected, and a radiator (3) for generating an ultraviolet light, which radiator (3) is equipped for irradiation of the sump region (19) with the light, characterised in that the radiator (3) has a pivotable screen (14) which prevents a part (20) sensitive to the light, particularly stock (20) to be treated, from being irradiated.
2. Domestic appliance (18) according to claim 1, in which the radiator (3) is equipped for generating light at a preferred wavelength of 253.7 nanometres.
3. Domestic appliance (18) according to any one of the preceding claims, in which the pump device (6, 7, 17) comprises an outflow duct (17) and in which an additional radiator (4) for generating an ultraviolet light and irradiation of the outflow duct (17) is arranged in the outflow duct (17).
4. Domestic appliance (18) according to any one of the preceding claims, which comprises a drying device (9, 10, 11, 12) particularly a drying device (9, 10, 11, 12) comprising a fan (11) for drying the chamber (2).
5. Domestic appliance (18) according to claim 4, in which a heat source (3, 16) for acceleration of the drying is associated with the chamber.
6. Domestic appliance (18) according to claim 5, in which the radiator (3) is the heat source (3, 16).
7. Domestic appliance (18) according to one of claims 5 and 6, in which an immersion heater (16) for heating the liquid for treatment of the stock (20) is the heat source (3, 16).
8. Domestic appliance (18) according to any one of claims 5 to 7, in which the drying device (9, 10, 11, 12) comprises an air feed channel (9) for feeding dry air to the chamber (2) and an exhaust air channel (10) for discharge of moist exhaust air from the chamber (2).
9. Domestic appliance (18) according to any one of the preceding claims, which is a washing machine (18) for washing the stock (20).
10. Domestic appliance (18) according to claim 9, in which a rotatable drum (1) for reception of the stock (20) is arranged in the chamber (2).

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