WO1989009068A1

WO1989009068A1 - Process and appliance for disinfecting and/or deodorizing the interior space of a microwave oven and for sterilizing objects contained therein

Info

Publication number: WO1989009068A1
Application number: PCT/EP1989/000345
Authority: WO
Inventors: Paul Hirsch
Original assignee: Paul Hirsch
Priority date: 1988-03-30
Filing date: 1989-03-30
Publication date: 1989-10-05
Also published as: AU3341589A

Abstract

An ultraviolet emitter for producing ozone is placed in the microwave field of a microwave oven and can be activated by this field. Said ozone, which is either prepared in the cooking space of the microwave oven or in a container arranged therein or fed into this space, oxidizes odorous substances contained in the outgoing air from the microwave oven and reaches the outgoing air flue with said outgoing air, thus keeping the deposits which have accumulated therein germ-free. Conversely, the ozone cannot escape from said container, but becomes more concentrated in harmless proportions and thus rapidly sterilizes all objects contained in said container. Preferably, the inside of the container is shielded against the microwaves.

Description

Method and device for disinfecting and / or deodorising an interior arranged in the interior of a microwave oven and for sterilizing goods arranged in such an interior

The invention relates to a method according to claim 1 and an apparatus for performing this method according to claim 2.

Microwave ovens have an exhaust air duct in which condensates of fat, water and the like are additionally deposited with solid particles over time, which are entrained with the exhaust air from the cooking space of the microwave oven. This precipitation forms a breeding ground for germs.

In addition, cooking smells arise in the cooking space of a microwave oven and are emitted to the environment through the exhaust air duct.

Known sterilization devices generally have a steam generator as the sterilization device, which produces a certain temperature in the interior of the container of the sterilization device for a certain period of time, which are coordinated in such a way that germs are reliably killed off.

Due to the required overpressure, extensive safety measures must be taken when designing the device; Because of the relatively long sterilization time and the required cooling times for the items to be sterilized, use is cumbersome.

If, for example, because of a sterilization process that is too short, germs still remain in the item to be sterilized, then they can readily multiply after cooling.

For the reasons described, such a sterilization device is not suitable for use in the household, for example for sterilizing food for babies or utensils for nursing babies. For sterilizing baby bottles, rubber teats a sterilization bath is generally used for this and the like, the particular disadvantage of which is that the sterilizing chemicals can form residues.

The invention has for its object to suppress the occurrence of cooking smell and to reliably kill germs that may have accumulated in the exhaust air duct, avoiding complex structural changes in the microwave oven.

This object is achieved by the method of claim 1 and the device of claim 2.

In this case, according to the invention, a UV lamp is exposed to the microwave field generated by the microwave oven, this UV lamp being set up in such a way that the UV radiation it emits converts the atmospheric oxygen it has hit into ozone. The UV lamp is preferably designed as a low-pressure lamp which is set up to emit UV-C rays.

According to the invention, this UV lamp is attached or attachable in such a way that the UV radiation emanating from it either impinges directly on the air in the cooking space and converts part of its atmospheric oxygen into ozone or is connected to this interior space by at least one air passage through which ozone generated by the UV lamp can get into the cooking space of the microwave oven.

In this way, the ozone generated already encounters odorous substances in the cooking space of the microwave oven and oxidizes them. Furthermore, due to the suitable dimensioning of the UV lamp and / or in operating periods in which sufficiently free ozone remains due to the low accumulation of odorous substances, this ozone enters the exhaust duct of the microwave oven, where it kills any germs that may have formed and also kills them. Starting from the prior art mentioned at the outset, the invention is also based on the object of finding a sterilization device which is simple in construction and simple and reliable in operation, which enables rapid and reliable but residue-free sterilization of items of sterilization of all kinds and also for germ-free Storage of sterile goods is set up.

This object is solved by the features of claims 2 and 3.

Here, the interior is not formed by a component of the microwave oven, but by an unventilated container in which ozone is generated or introduced into the ozone by the above-mentioned UV lamp, which forms a sterilization device. Since the container is not ventilated and is also relatively small, an ozone concentration is established in the interior, which is suitable for the rapid and effective sterilization of food, medical devices and materials as well as articles for baby care.

The UV lamp used in the sterilization container has essentially the same features as that which is used for deodorising the cooking space and which is described below.

In principle, it is possible to use a commercially available UV lamp provided with connections as the UV lamp, which is optionally protected by a preferably adjustable shield against the entry of an excessive microwave field.

It has also been found to be suitable to use only a quartz glass container as the UV lamp, which is filled with a suitable gas, but otherwise no electrodes or Connections, because the gas filling is activated directly by the microwave field.

After tests, however, a UV lamp that has the properties described in the further claims has proven to be particularly advantageous.

Here, the UV lamp is preferably designed as a low-pressure lamp and filled with a mixture of argon and mercury vapor, the mixing ratio of which is adjusted so that the most uniform possible operation is ensured.

This gas filling is accommodated in the interior of an elongated quartz glass container, into which an electrode-like internal antenna is preferably introduced from both sides, which preferably terminates in a helical, thickened end in the interior of the gas. The two mutually opposite internal antennas do not form electrodes in the conventional sense, so that such a UV lamp cannot be operated even after galvanic connection to conventional starting electronics, but can only be operated by a high-frequency field.

The two internal antennas are connected to the outside of the quartz glass container via lead wires and are there in heat-conducting connection with heat sinks to prevent the lead wires from burning out. Furthermore, a low resistance running parallel to the UV lamp is connected to the line wires in order to avoid overloading the UV lamp.

The heat sink and the parallel resistor are preferably designed as metal brackets, the main part of which extends along the UV radiator and is clamped with its two end sections to the lines which are led out of the quartz glass body and folded over against them, the antenna bracket preferably forming free end sections which are separated from the UV Spotlights are spread. Here, the antenna bracket forms the parallel resistance, dissipates the heat from the lead wires, but is nevertheless also effective as an antenna and is also used to clamp the UV lamp in the interior of a microwave-permeable, ozone and heat-resistant tube in which the UV lamp is protected,

In the arrangement described, it is possible to operate the UV lamp evenly in a cooking space in which there is a pulsating microwave field due to the rotating food.

The UV lamp or the tube receiving it is preferably arranged in a holder arrangement described in the subclaims made of heat and ozone-resistant plastic, two covers receiving the two ends of the tube having openings in order to allow ozone to escape. In this case, the tube shields the UV radiation, so that cookware directly exposed to UV radiation cannot be damaged. Only the ozone generated by the UV lamp inside the tube is directed into the cooking space of the microwave oven.

The holder is set up in such a way that a minimum distance between the antenna bracket or UV lamp on the one hand and the outer wall of the microwave oven on the other is maintained in order to avoid any arcing.

For particularly convenient attachment, a holding magnet is preferably attached to the holder, which can be designed as a steel magnet, but is preferably designed as a sintered or ceramic magnet. This magnet is surrounded by a closed metal capsule in order to be shielded from the microwave field, which would otherwise unduly heat it.

An additional advantage of the invention is that it also UV light emitting visible light during the cooking process serves as additional lighting for the interior of the microwave oven and thus enables observation of the cooking process.

When using a closed sterilization container which can be inserted into the cooking space of the microwave oven, the UV lamp is arranged in a chamber which is connected via at least one air or. Gas passage is connected to the inside of the sterilization container.

This sterilization container is microwave-proof and preferably consists of aluminum sheet. The UV lamp, on the other hand, is arranged in such a way that, when the sterilization device is arranged in the cooking space of a microwave oven, it is activated by the microwaves occurring there.

It is thus generated by the UV lamp ozone, which accumulates inside the container and thus effectively and quickly kills all germs that occur there.

Because of the high nitrogen content of the air originally present in the container, the formation of an explosive ozone concentration is avoided.

When the container is opened, the ozone evaporates immediately, so that it is harmless despite its toxicity.

Ozone cannot form ozone residues on the surface of sterilized objects; at most, it leads to the formation of oxides, which is harmless in the case of food, for example.

Since neither an overpressure nor an excessive temperature occurs inside the container, the use of the sterilization device according to the invention is completely foolproof. The use of an existing microwave oven saves the need for a complex, own energy supply. The smell of the ozone escaping when the container is opened makes it clear to the user that sterilization has actually taken place.

Insofar as ozone has been generated in the interior of the container, even after the microwave field has been switched off, any remaining germs are effectively killed off.

The sterilization device is preferably designed as a structural unit, in which a single UV lamp is preferably arranged.

However, it is also possible to provide several UV lamps in this structural unit or to form the sterilization device from several partial devices distributed over the device.

The UV lamp is preferably located in a tube, as already described above. The ends of the tube are provided with perforated, gas-permeable, microwave-impermeable metal covers; the outside of the tube is surrounded by a shield. This shielded tube is arranged inside the lid, preferably close to an opening, the shield being connected to the edges of the opening and the tube and thus the UV radiator being exposed to the entry of microwaves through the opening.

A holding block is preferably attached to the outside of the opening, in which the shield is fastened and which in turn is preferably detachably fastened to the cover. This holding block thus carries all parts of the sterilization device.

As the holding block can be removed, all parts of the sterilization device can be easily removed for cleaning and replacement. In addition, if necessary, a microwave-permeable cover in the Lid of the sterilization container are attached so that water can be brought to the boil in the lower part of the sterilization container by microwave radiation. If necessary, the sterilization container can also be used for steam sterilization, for example when a special item to be sterilized should oxidize excessively when exposed to ozone.

The tube forming the chamber is preferably made of translucent material, such as glass, and the holding block preferably has a viewing shaft, so that the lighting of the UV lamp can always be observed through the door window of the microwave oven, so that any malfunction that occurs is immediately recognizable .

Centerings are also preferably attached to the lid and lower part of the container in order to ensure that the microwave-tight connection between these two elements is always ensured and mutual displacement, which could also lead to arcing, is prevented.

The object of the invention is explained in more detail, for example, with the aid of the attached schematic drawing. In this shows:

1 shows a device for generating ozone which can be attached in the cooking space of a microwave oven,

2 shows a sterilization device according to the invention, in a partially sectioned side view, for insertion in the cooking space of a microwave oven, and

Fig. 3 is a partially sectioned front view of the device shown in Fig. 2.

The drawing is not to scale; For the sake of clarity, the sterilization device is also shown slightly enlarged in FIGS. 2 and 3. In Fig. 1, a device for attachment to the chrome steel inner wall of the cooking space of a microwave oven is shown to deodorize the exhaust air from the microwave oven and to disinfect inaccessible parts of the microwave oven.

The device shown has a UV lamp 1, which is formed from a quartz glass tube filled with argon and mercury vapor and is sealed. and both ends of which are flattened, the extension of these ends being transverse to the plane of the drawing.

Through the flattened ends, internal antennas 6 'are passed inwards, each of which ends in the interior of the quartz glass tube 1 in the form of a lobe-like thickening formed by a wire coil.

The outer ends of the inner antennas 6 'are turned around the flattened ends of the quartz glass tube 1 and clamped to the quartz glass tube by the two ends of an antenna bracket 2 made of relatively thick sheet metal.

This antenna bracket 2 extends with a central section along the UV lamp 1, clamps the two internal antennas 6 'in the manner described and is spread out on the side opposite the central section with two end sections from the UV lamp 1. Edges that occur, particularly at the free ends of the antenna bracket 2, are rounded off in order to prevent sparks from escaping.

The antenna bracket 2 is dimensioned such that it can be inserted with a slight fit into the inside of a circular-cylindrical glass tube 3, where it prevents the UV lamp from slipping and twisting.

The glass tube 3 sits with each of its two ends in a clamp holder 5 made of ozone and heat-resistant plastic, which covers the end of the glass tube and, as clearly shown in the drawing by an end view of the device, has openings. through which the ozone generated inside the glass tube 3 can escape unhindered. In one piece with the clamp holders 5 is a support 4, which extends parallel to the glass tube 3 and at a distance from it, in the middle of which a recessed magnet 6 is made, which consists of sintered material and is enclosed on all sides by a sheet metal capsule.

The device can easily be attached to and removed from an interior wall of the cooking space, an optimal attachment point being easily determined with regard to the exhaust air openings and the field distribution. For cleaning, the whole device can either be disassembled, e.g. in the dishwasher, or it can be easily disassembled and cleaned piece by piece.

The sterilization container shown in FIGS. 2 and 3 is formed from a flat, bowl-shaped lower part 18 with a flange-like protruding edge and a similar upper part 17. At the longitudinal ends of the flange-like edge, an upper handle part 19 is attached to the upper part 17, while a lower handle part 20 is arranged on the lower part 18 opposite the respective upper handle part 19.

As can be seen from the drawing, the upper grip part 19 has at its free end a downward, pin-like projection which engages in a centering receptacle in the lower grip part 20. As a result, the two protruding flanges of the cover 17 and the lower part 18 are pressed firmly and in alignment with one another.

In the top of the cover 17 there is an opening, in addition to the top and bottom sides (narrow sides) of which a bore is formed for receiving a clamping plug 16.

The actual sterilization device sits in the opening is formed by a UV lamp 1, which is provided with two internal antennas and is enclosed by an antenna bracket 2. The antenna bracket 2 forms the heat dissipation for the line-like feedthroughs of the internal antennas, forms a parallel resistor to the UV lamp 1 and is located in a light press fit within a glass tube 3, which is arranged below the opening in the cover 17 and thus inside the sterilization container 17, 18 is.

The ends of the tube 3 sit in each of my end cap 14 made of aluminum sheet, which, as can be seen in FIG. 3, have perforations 23, the width of which is dimensioned such that ozone can escape unhindered from the chamber formed by the tube 3, but not microwave radiation .

As can be seen from FIG. 3, the tube 3 is wrapped in a shielding plate 22 which extends over the entire length of the tube 3. Clamping rings 21, which are arranged at both ends of the tube 3, encompass the respective metal end cap 14 and the shielding sheet metal strip 22 placed around them and hold these elements together with the tube 3.

As can be seen from FIG. 3, the upper ends of the shielding sheet metal strip 22 are bent outward and engage resiliently in each case in a longitudinal groove in a handle 15, on each of which a clamping plug 16 is formed on its longitudinal sides, with which the entire ozone generator is clamped on the cover 17 .

The handle part 15 is made of microwave-permeable material and has a central shaft through which the visible light emitted by the UV lamp 1 can exit.

During operation, material to be sterilized is placed in the lower housing part 18, the cover 17 is placed on it, the upper handle and lower parts 19, 20 are locked together. Now the closed device is placed in the cooking space of a microwave oven and the microwave oven is switched on for a predetermined operating time. The lighting of the spotlight 1 through the shaft inside the handle part 15 can be observed.

The sterilization process can be interrupted at any time in order to remove or insert good from the sterilization container 17, because neither the container nor the product heat up to any appreciable extent.

For hygienic reasons, the inside of the container 17, 18 is designed so that angles in which dirt could accumulate are avoided as far as possible.

The inner surfaces of cover 17 and lower housing part 18 are preferably painted or anodized.

Claims

1. A method for disinfecting and / or deodorising at least one interior inside a microwave oven and / or for sterilizing goods arranged in such an interior, characterized in that - a UV lamp, the radiation for converting the atmospheric oxygen it hits into Ozone is suitable, is exposed to the microwave field generated by the microwave oven, and - that the air in the interior is exposed to the ozone-generating UV radiation and / or the ozone generated by this radiation is introduced into this interior.

2. Apparatus for carrying out the method according to claim 1, characterized in that it has a UV lamp (1), the radiation of which is suitable for converting the atmospheric oxygen it has hit into ozone, and in that the UV lamp (1) in Interior can be attached or connected to it through an air passage.

3. Apparatus according to claim 2, characterized in that the interior is designed as a closable container with a lid for receiving goods to be sterilized, which can be arranged in the cooking chamber of the microwave oven.

4. Device according to one of claims 2 or 3, characterized in that the UV lamp (1) is designed as a closed quartz glass container, the interior of which is filled with a gas which can be activated by microwaves.

5. Apparatus according to claim 4, characterized in that the gas is a mixture of argon and mercury vapor.

6. Device according to one of claims 4 or 5, characterized in that at least one internal antenna (6 ') is arranged in the interior of the quartz glass container.

7. Apparatus according to claim 6, characterized in that two mutually opposite inner antennas (6 ') are provided.

8. Device according to one of claims 6 or 7, characterized in that the inner antenna (s) (6 ') is or are formed from a wire coil.

9. Device according to one of claims 7 or 8, characterized in that the two inner antennas (6 ') are each connected to the outside of the container by a line wire passing through the wall of the quartz glass container (1).

10. Apparatus according to claim 9, characterized in that the outer ends of the lead wires are each connected to a heat-dissipating heat sink (2).

11. Device according to one of claims 9 or 10, characterized net that the two outer ends of the lead wires are connected to each other via a parallel resistor (2).

12. Apparatus according to claim 10 or 11, characterized by an antenna bracket (2) made of metal, which is clamped with its two ends to the two outer ends of the lead wires, connects them to one another and thus forms both the heat sink and the parallel resistor at the same time.

13. Apparatus according to claim 12, characterized in that the edges of the antenna bracket (2) are rounded.

14. Device according to one of claims 2 to 13, characterized in that the UV lamp (1) is arranged in a mountable on the wall of the interior of the microwave oven holder (3, 4, 5) made of electrically insulating material so that a The minimum distance between the UV lamp (1) and the wall of the interior is maintained.

15. Apparatus according to claim 14, characterized in that the holder (3, 4, 5) has a tube (3) which is open on both sides and is made of microwave-permeable material, in which the UV lamp (1) is arranged,

16. Apparatus according to claim 15, characterized in that the tube (3) consists of glass.

17. Device according to one of claims 15 and 16, characterized in that the antenna bracket (2) extends with a main part along one side of the UV lamp (1), with its two ends embraces the ends thereof with the clamping of its lead wires and with two free end sections protruding from the opposite side of the UV lamp (1), and that the antenna bracket (2) with the main part on the one hand and with the free end sections on the other is supported in the tube (3), if necessary with a slight pressure fit.

18. Device according to one of claims 15 to 17, characterized in that the ends of the tube (3) are covered and held by perforated holder sections (5) which are connected to one another by a support (4) extending parallel to the tube (3) are.

19. Device according to one of claims 14 to 18, characterized in that a holding magnet (6) is arranged in the holder, preferably in the carrier (4), on a side facing away from the UV lamp (1), which is used to fasten the device the wall of the interior is set up.

20. Apparatus according to claim 19, characterized in that the holding magnet (6) consists of sintered material and is surrounded by a closed sheet metal capsule.

21. Apparatus according to claim 3, characterized g e k e n n z e i c h n e t,

- That the container (17, 18) is impermeable to microwaves when the lid (17) is in place,

- That the surface of the interior of the container (17, 18) is ozone-resistant, and

- That a sterilization device with at least one UV lamp (1) is provided, which is set up to convert the surrounding atmospheric oxygen into ozone and is arranged in a chamber (3), the cavity of which can be exposed to the microwave radiation of the microwave oven and to the interior of the Container (17, 18) is connected by a gas passage (23).

22. Apparatus according to claim 21, characterized in that the steri Lisationseinrichtung (1, 2, 3, 14, 15) is arranged in an opening of the lid (17).

23. Apparatus according to claim 21, characterized in that - the chamber is formed by a tube (3) made of microwave-permeable, heat-resistant and ozone-resistant material, which is arranged inside the cover (17) near the opening,

- That the two open ends of the tube (3) are each closed by a perforated metal cover (14) whose hole size is dimensioned so that no microwaves can pass through, and

- That the outer circumference of the tube (3) is surrounded by a shielding plate (22) which connects with each of its ends to the associated edge of the opening and leaves the tube (3) to the opening.

24. Apparatus according to claim 23, characterized in that the ends of the shielding plate (22) are fastened in a holding block (15) which is preferably designed as a lid handle and which is attached to the outside of the lid (17).

25. Apparatus according to claim 24, characterized in that the tube (3) is made of translucent material, preferably of glass, and that the holding block (15) has an observation recess leading to the opening.

26. Device according to one of claims 24 or 25, characterized in that the holding block (15) is removably attached to the lid.

27. Device according to one of claims 21 to 26, characterized in that a cooperating centering (19, 20) is formed on the lid (17) and on the container lower part (18) in order to ensure the microwave-tight connection of these parts.