DE102011080073B4 - household appliance door with lighting device - Google Patents

Abstract

Household appliance door (1) in the form of an oven door for closing a loading opening (11) of a receiving space (12) of a household appliance (13) in the form of an oven, wherein
- the household appliance door (1) has at least two lighting devices (16) each with at least one light emitting element (17, 18) for illuminating the receiving space (12) and
- the lighting device (16) has at least one reflector (28) which partially surrounds at least one light emitting element (17, 18) illuminating the reflector (28),
- the reflector (28) is a vertical reflector (28) which is tubular with at least one light exit opening (29) formed in a lateral surface (28a), which is directed into the receiving space (12) and extends over the entire length of the lateral surface (28a), characterized in that
- the household appliance door (1) has two laterally arranged door profiles (2) which are connected to one another by a rectangular frame (3) and to which at least one front pane (4) and one inner pane (8) are attached,
- the reflectors (28) run parallel to a respective door profile (2) and are arranged between the inner pane (8) and an adjacent pane (5-7),
- the reflectors (28) extend at least over a height of the loading opening (11) and
- the reflectors (28) thermally shield an adjacent, laterally arranged door profile (2).

Description

The invention relates to a household appliance door in the form of an oven door for closing a loading opening of a receiving space of a household appliance, wherein the household appliance door has at least one lighting device with at least one light source for illuminating the receiving space. The invention further relates to a household appliance with such a household appliance door in the form of an oven door.

EP 1 995 522 B1 discloses an oven, within the oven door of which there are lighting means for illuminating an oven muffle that can be closed by the oven door. These lighting means have several light sources that radiate their light in a focused manner directly in the direction of the oven muffle. The light sources can be LEDs arranged in a row, each of which directs its light towards the oven muffle. For this purpose, it is shown that the LEDs are attached to a sheet metal support in a left and right area of the oven door, with the LEDs being aligned by means of a corresponding local alignment of the sheet metal support. The oven door can be cooled by means of natural ventilation. However, the oven door is comparatively complex in design. The LEDs are also only inadequately protected against high temperatures, such as those that occur during pyrolysis operation.

In addition, the publication reveals US 2009/0 316 385 A1 an oven light comprising an LED assembly or assemblies optically coupled to an optical guide element. The light also includes a mounting bracket and a pair of electrical leads to connect the LED light to an external voltage source. The LED assembly consists of an LED attached to a circuit board which includes additional circuitry for powering the LED and a heat sink for dissipating heat from the LED. The mounting bracket can be attached to a door of the oven cavity to support the LED light adjacent to a sidelight window. The mounting bracket has a slot adjacent to the window to transmit the light from the LED through the light guide into the oven cavity. By positioning the light outside the oven cavity and adjacent to the sidelight window, the LED can be operated within required temperature limits.

In addition, the publication reveals DE 10 2005 045 367 A1 an interior lighting device for a cooking appliance with a lighting unit for radiating lighting light into an interior of the cooking appliance. In order to provide an interior lighting device for a cooking appliance which can be produced particularly cost-effectively and which can also be operated in an energy-saving manner with a safe low-voltage power supply, it is proposed that the lighting unit comprises at least one light-emitting diode.

In addition, the publication reveals DE 38 27 528 A1 a device for lighting a cooking chamber, whereby a lamp is installed between two protective glass panes to protect against high temperatures and aggressive influences.

It is the object of the present invention to at least partially overcome the disadvantages of the prior art and in particular to provide a simply constructed household door equipped with at least one lighting means, in which the lighting means can be better protected against high temperatures.

This object is achieved according to the features of the independent claims. Preferred embodiments can be found in particular in the dependent claims.

The object is achieved by a household appliance door in the form of an oven door for closing a loading opening of a receiving space, wherein the household appliance door in the form of an oven door has at least two lighting devices, each with at least one light emitting element for illuminating the receiving space. The lighting device has at least one reflector, which partially surrounds at least one light emitting element illuminating the reflector. This increases the light output and enables a diverse light orientation and consequently a more targeted illumination of the receiving space.

Because the reflector only partially surrounds the at least one light emitting element (circumferentially), at least one light passage opening is created in the reflector through which light can exit the reflector. The light exiting through the at least one light passage opening can either be emitted directly by the at least one light emitting element and/or reflected by the reflector. The at least one light passage opening in the area of a light emitting element also prevents the reflector from being used as a light channel that only transmits light.

According to the invention, the reflector is tubular with at least one light exit opening formed in a lateral surface. The light exit opening is directed into the receiving space. In this way, a large-area reflection with a good defined beam shaping, which keeps light losses to a minimum.

The profile of the tubular reflector can be, for example, circular-cylindrical, oval, square and/or free-form in sectors.

According to the invention, the light exit opening extends over substantially the entire length of the outer surface of the reflector.

According to the invention, the household appliance door has two laterally arranged door profiles which are connected to one another by a rectangular frame and to which at least one front pane and one inner pane are attached,

According to the invention, the reflectors run parallel to a respective door profile and are arranged between the inner pane and an adjacent pane,

According to the invention, the reflectors extend at least over a height of the loading opening. The reflector can be arranged in particular between the receiving space and the door profile. Such a reflector can in particular be a vertical reflector. If the light guide represents the light emitting element, the light guide can also serve as a heat shield, so that the door profile is doubly thermally shielded from the receiving space.

According to the invention, the reflectors thermally shield an adjacent door profile. The reflector can therefore serve in particular as a heat shield, in particular to thermally shield a door profile from the receiving space.

Another option is for the door profiles to be made of plastic.

Another embodiment provides that at least one intermediate pane is additionally attached to the door profiles and the reflectors are arranged between the inner pane and an adjacent intermediate pane.

Another embodiment is that the at least one light emitting element illuminating the reflector has at least one light guide. Light emerging from the light guide can therefore be at least partially reflected into the receiving space by means of the reflector.

Light from at least one light source can be coupled into a light guide. The light guide is therefore arranged and designed to transmit the light coupled into it and to radiate it (directly and/or indirectly) into the recording space. By providing at least one light guide, particularly uniform and wide-angle illumination of the recording space can be achieved in a simple manner. A light guide can also be designed to be particularly thermally insensitive, e.g. if it is made of glass or glass ceramic.

One embodiment is that the light guide has at least one surface area where light emission is prevented or suppressed, and at least one surface area which is intended for light emission, wherein the at least one surface area preventing or suppressing light emission is directed towards the reflector. This facilitates targeted illumination of the recording space in a compact manner and suppresses a portion of the light reflected by the reflector. Alternatively, the light guide may specifically radiate light onto the reflector in order to achieve a more directed light emission pattern.

It is a special embodiment that the at least one surface area of the light guide that prevents or suppresses light emission is masked, in particular coated or roughened to be opaque. For example, a light guide can be coated to absorb light where light emission is to be prevented or, preferably for high light output, to reflect light. Roughening or other microstructuring can be achieved, for example, by sandblasting or etching and makes the roughened surface area appear milky or diffuse. The roughening or other microstructuring causes diffuse back-emission or reflection of the light into the light guide, often at an angle that causes increased light emission from the light guide at the location of the light guide illuminated by the back-reflection. Consequently, light is emitted in particular more strongly from an uncoated or roughened (i.e., smooth) area of the light guide.

It is an advantageous development for uniform light emission over its length that the light guide is designed or prepared at a circumferential angle α that is constant over its length around its longitudinal axis L for targeted light emission. However, the invention is not limited to this, and the circumferential angle α can change with the length of the light guide.

The circumferential angle α is preferably in a range between approximately 45° and approximately 270°, so that in a further development, light can emerge in the complementary circumferential angle range between approximately 315° and approximately 90° (at which the surface of the light guide in particular smooth and uncoated). The light guide can also have areas spaced apart along its length, which, for example, have an equal circumferential angle α to one another. The areas can be arranged in a row or, for example, at an angle offset around the longitudinal axis.

One design is that the light guide is made of a glass-like material (glass, glass ceramic or similar). The glass is preferably borosilicate glass. Glass-like material is highly temperature-resistant and typically transparent. An optical property can be changed easily and precisely by adding fillers. For example, the light guide can be designed as a diffusely scattering light guide. In addition, glass-like material is comparatively inexpensive, versatile in its form and its surface is easy to re-treat.

Alternatively, the light guide may be made of plastic, which further simplifies production. The plastic is preferably a highly temperature-resistant plastic.

The plastic preferably consists of polycarbonate (PC), acrylonitrile butadiene styrene (ABS) and/or polymethyl methacrylate (PMMA).

The light guide can in particular be a light guide that can guide light within its material or body (“light guide body”). The light guide is in particular a body that can guide light by means of total internal reflection (TIR body). The light guide is in particular a solid body.

It is a further development that a thickness of at least one light guide is preferably between 5 mm and 30 mm. However, the thickness is not limited to this.

It is also a further development that a cross-sectional profile of at least one light guide is curved at least in sections and can in particular be circular-cylindrical, circular-segment-shaped or oval. For a broad light emission, a curved or more strongly curved area of a lateral surface of the light guide preferably faces the receiving space. However, the cross-sectional profile is not limited to this, but can also be angular and/or free-form, for example.

The light guide is preferably straight, but can also be curved.

Another embodiment is that the at least one light emitting element illuminating the reflector has at least one light source directed at the reflector. The light emitting element therefore essentially only radiates onto the reflector and only illuminates the recording space indirectly. In this way, at least a comparatively warm light emitting surface of the at least one light source can be protected from direct heat radiation from the recording space. The reflector also enables more versatile beam shaping and, particularly in the case of a diffuse reflector, more uniform and larger-area light emission.

In yet another embodiment, at least one light source has a heat shield on a side facing away from the reflector (i.e., the side facing the light passage opening). The heat shield can be formed, for example, by a holder for the light source. In this way, the light source can be protected even more effectively against heat radiation from the recording space.

The reflector can be specular and/or diffusely reflective. Diffuse reflection supports a uniform light output from the reflector, whereas specular reflection supports a directional effect.

It is also an embodiment that the light exit opening has an opening angle γ between approximately 90° and approximately 270°. It is advantageous for loss-free illumination when using a light guide as the light emitting element that a complementary circumferential angle (1-α) of the light guide at least approximately corresponds to the opening angle γ of the light exit opening.

It is also an embodiment that the reflector represents a holder for at least one further element of the lighting device. This allows simplified assembly with low position tolerances. The further element can be, for example, a light guide and/or a carrier for at least one light source.

The reflector can be a single-part or multi-part design. In a multi-part design, different parts can be used for different functions, e.g. for reflecting, supporting, positioning, etc., which helps to standardize components and also facilitates more uniform assembly.

For lower temperatures, the reflector can be a plastic body with a reflective coating, for example. For higher temperatures, the reflector can be a reflective coated or a shiny polished metal body, for example. A reflective coating can be made of aluminum and/or chrome, for example.

The reflector can also be designed as a heat sink. The reflector can have at least one cooling structure (cooling fins, cooling pins, etc.), in particular on a side facing away from the at least one light emitting element.

Another embodiment is that at least one reflector, in particular with the at least one light emitting element illuminating it, is arranged between an inner pane and an adjacent pane (e.g. a front pane or an intermediate pane). This enables particularly high lighting efficiency. In addition, if at least one intermediate pane is present, good thermal shielding of the front pane is possible, since the at least one intermediate pane can then be made thick without influencing the lighting.

Another embodiment is that at least one reflector, in particular with the at least one light emitting element illuminating it, extends at least over a height of the loading opening. In this way, the receiving space can be illuminated over its entire height, even if at least one insertion level or similar is occupied. The reflector is preferably aligned vertically.

In principle, one, two or more reflectors can be provided, in particular with at least one respective light emitting element. At least one reflector can be set up and arranged to illuminate several (in particular all) insertion levels of the receiving space, in particular a vertical reflector.

A reflector, in particular with at least one respective light-emitting element, can be arranged vertically or horizontally. A vertical arrangement enables illumination over the height of the receiving space, in particular over several insertion levels. A vertical reflector preferably runs parallel to a door profile of the household appliance door. In order to provide the largest possible viewing area, at least one vertically arranged reflector can be arranged in particular in an area of a left edge (reflector arranged on the left side) and/or a right edge (reflector arranged on the right side) of a viewing window of the household appliance door.

In particular, two reflectors with at least one respective light emitting element may be provided to illuminate a shelf level. This reduces the formation of shadows in the receiving space. A reflector arranged on the left side and a reflector arranged on the right side can in particular be designed and/or arranged mirror-symmetrically to a door center axis in order to support uniform illumination of the receiving space.

Alternatively, at least one reflector may be set up and arranged to illuminate only one insertion level at a time. For this purpose, the reflector can be arranged horizontally in particular to enable uniform illumination across the width of the receiving space. To provide the largest possible viewing area, a horizontally arranged reflector can be arranged in particular in an area of an upper edge and/or a lower edge of a viewing window of the household appliance door.

In a further embodiment, an intermediate piece is connected upstream of the light guide, into which light from at least one light source can be coupled and which transmits the coupled light to the light guide. The intermediate piece enables effective light coupling from the at least one light source and consequently a high light output.

It is also possible for the intermediate piece to be or have an optical element. This makes it possible to achieve particularly versatile beam guidance, in particular for a high light output.

It is also an embodiment that at least one light guide, the associated intermediate piece and the at least one light source radiating light into the intermediate piece are arranged collinearly, which enables a high photometric lighting efficiency. For this purpose, a length of the respective light guide is in particular less than a height of the oven door.

Another embodiment is that at least one light guide extends into a cold area of the household appliance door and the at least one (associated, i.e. light radiating into this light guide directly or indirectly, e.g. via an intermediate piece) light source is also located in the cold area. The cold area is intended to be arranged to the side of the loading opening when the household appliance door is closed. A cold area can therefore be understood in particular as an area of the household appliance door which does not cover the household appliance door when it is closed. By arranging the at least one light source in the cold area, it can be kept at a low thermal level even at high temperatures in the receiving space. In particular, the light source is not exposed to any direct heat radiation. Consequently, a particularly high service life of the lighting device, even if an associated household appliance is capable of pyrolysis.

The intermediate piece is also preferably housed in the cold area, especially in household appliances capable of pyrolysis. A particularly suitable development is for the intermediate piece to be made of plastic and the light guide to be made of glass. This provides an inexpensive and versatile light coupling and light transmission. Alternatively, the intermediate piece and the light guide can both be made of the same material, e.g. glass or plastic (e.g. polycarbonate, PMMA, etc.), in particular made in one piece. This simplifies production.

In general, the cold area can in particular be the cold area that is located on the side of the household appliance door on which it can be pivoted or has at least one door hinge. Such a cold area is comparatively large, so that sufficient, uncrowded space is available for accommodating the at least one light source.

One embodiment is that the cold area is a lower cold area. A lower cold area can be understood in particular as a cold area that is arranged below the loading opening when the household appliance door is closed. Such a cold area is available in particular for doors that open downwards, such as oven doors.

Alternatively, the cold area can be a side cold area, particularly in the case of a household appliance door that opens or pivots to the side (e.g. for refrigerators or microwave ovens) or, particularly in the case of a household appliance door that opens upwards or pivots to the top, an upper cold area (e.g. in the case of a high-mounted appliance).

Another embodiment is that at least one light guide extends parallel to a side door profile at a distance of up to 150 mm. Another embodiment is that the at least one light source is arranged in a partial area of the lower cold area, which extends up to 100 mm from a lower door edge and/or up to 150 mm from side door profiles.

In yet another embodiment, the at least one light source comprises at least one semiconductor light source. A semiconductor light source is particularly long-lasting, structurally compact and can generate a high luminous flux.

Preferably, the at least one semiconductor light source comprises at least one light-emitting diode. If there are several light-emitting diodes, these can light up in the same color or in different colors. A color can be monochrome (e.g. red, green, blue, etc.) or multichrome (e.g. white). Several light-emitting diodes can produce a mixed light; e.g. a white mixed light. The at least one light-emitting diode can contain at least one wavelength-converting phosphor (conversion LED). The phosphor can alternatively or additionally be arranged remotely from the light-emitting diode (“remote phosphor”). The at least one light-emitting diode can be in the form of at least one individually housed light-emitting diode or in the form of at least one LED chip. Several LED chips can be mounted on a common substrate (“submount”). The at least one light-emitting diode can be equipped with at least one separate and/or common optics for beam guidance, e.g. at least one Fresnel lens, collimator, and so on. Instead of or in addition to inorganic light-emitting diodes, e.g. based on InGaN or AllnGaP, organic LEDs (OLEDs, e.g. polymer OLEDs) can also generally be used. Alternatively, the at least one semiconductor light source can have, for example, at least one diode laser.

The household appliance door can have at least one electrical connection to the associated (remaining) household appliance in order to supply power to the at least one light source. When using at least one light-emitting diode, an associated driver can be present in the household appliance door, in particular in the cold area, or alternatively in the (remaining) household appliance.

Another design feature is that the household appliance door can be forced ventilated. This further reduces the temperature in the household appliance door, which extends the service life of its components and improves user safety from high temperatures. Another feature is that at least the cold area can be forced ventilated. This means that the light sources that generate waste heat can be cooled particularly effectively.

It is also an embodiment that the at least one light source is thermally conductively connected to at least one heat sink. This improves heat dissipation and cooling of the light source and thus its service life. The heat sink can simultaneously represent a holder for the light-emitting diode for a compact design and easy installation. The heat sink or holder can be attached to a reflector and in particular pre-assembled to it for inexpensive production, to reduce assembly tolerances and for easy installation.

Another embodiment is that the cold area is separated from a warm area that covers the loading opening when the household appliance door is closed by means of a partition, and the partition has at least one light transmission opening for passing through light generated by the at least one light appliance. This facilitates light guidance between the cold area and the warm area. The partition can be at least partially permeable to air in order to allow a cooling air flow between the panes of the household appliance door. Another embodiment is that at least one light guide extends through a light transmission opening. This means that elements upstream of the light guide can be accommodated in the cold area, where they are thermally protected.

It is also an embodiment that the household appliance door is a cooking appliance door, in particular an oven door. The associated household appliance is therefore an oven, in particular an oven, whose accommodation space can also be referred to as an oven space or (in the case of an oven) as an oven. In particular in an oven, in particular an oven, pyrolysis can be carried out and effective lighting is required due to the comparatively large accommodation space (oven space).

It is also an embodiment that the lighting devices each have at least one light guide and at least one light source, the light of which can be coupled into the at least one light guide, and the reflector partially surrounds the light guide.

It is also an embodiment that the light guide consists of a glass-like material.

The object is also achieved by a household appliance in the form of an oven with at least one household appliance door in the form of an oven door as described above.

It is a design that the household appliance is a pyrolysis-capable household appliance.

The household appliance offers the same advantages as the household appliance door and can also be designed in a similar way.

The household appliance can in particular fall into the category of “white goods” and can be used in particular to carry out housework such as cooking, baking, washing, cleaning, etc. The household appliance can be a large household appliance (e.g. comprising a refrigerator, a freezer, a chest freezer, an electric stove, a washing machine, a dishwasher and a tumble dryer) or a small household appliance (e.g. comprising a microwave oven).

The household appliance can in particular be a kitchen appliance. It is particularly preferred that the household appliance is a cooking appliance (e.g. comprising an oven and/or a steamer), in particular an oven.

• 1 zeigt als Explosionsdarstellung in einer Ansicht von schräg hinten eine Backofentür;
• 2 zeigt in einer Ansicht von schräg hinten die Backofentür bei abgenommener rückwärtiger Scheibe;
• 3 zeigt die Backofentür aus 2 in einer Rückansicht;
• 4 zeigt einen Ausschnitt aus 2 im Bereich einer Lichtquelle;
• 5 zeigt einen Ausschnitt aus 3 im Bereich der Lichtquelle;
• 6 zeigt einen mit der Backofentür ausgerüsteten Backofen als Schnittdarstellung in Draufsicht mit einem zugehörigen Lichtabstrahlmuster;
• 7 zeigt in Schrägansicht einen weiteren möglichen Lichtleiter der Backofentür;
• 8 zeigt in Seitenansicht noch einen weiteren möglichen Lichtleiter der Backofentür;
• 9 zeigt als Schnittdarstellung in Draufsicht einen Reflektor mit einem Lichtabstrahlelement in Form eines Lichtleiters; und
• 10 zeigt als Schnittdarstellung in Draufsicht einen Reflektor mit einem Lichtabstrahlelement in Form einer Lichtquelle.

In the following figures, the invention is described schematically in more detail using exemplary embodiments. For the sake of clarity, identical or equivalent elements may be provided with identical reference numerals.

• 1 shows an oven door as an exploded view from behind;
• 2 shows a view from behind of the oven door with the rear pane removed;
• 3 shows the oven door 2 in a rear view;
• 4 shows an excerpt from 2 in the area of a light source;
• 5 shows an excerpt from 3 in the area of the light source;
• 6 shows an oven equipped with the oven door as a sectional view in plan view with an associated light emission pattern;
• 7 shows an oblique view of another possible light guide of the oven door;
• 8 shows a side view of another possible light guide for the oven door;
• 9 shows a sectional view in plan view of a reflector with a light emitting element in the form of a light guide; and
• 10 shows a sectional view in plan view of a reflector with a light emitting element in the form of a light source.

1 shows an exploded view of a basic structure of a household appliance door in the form of an oven door 1 in the form of an oven door. The oven door 1 has two door profiles 2 arranged on the sides, which are connected to one another by a rectangular frame 3. The frame 3 represents a lateral boundary of a viewing window.

A front pane 4 is attached to the front of the door profiles 2. For this purpose, the front pane can have several brackets 5 glued to the front pane 4, which can engage in the door profiles 2. At least one intermediate pane can optionally be inserted between the door profiles 2. be used, here for example two intermediate panes 6, 7. A rear side of the oven door 1 can be covered by an inner pane 8, which can also be fastened to the door profiles 2 by means of brackets 5 glued to it, for example. The oven door 1 is covered on the top over its entire width by an attachment 9, which has a door handle 10.

The frame 3 delimits, in a view from the front or rear, at least approximately an area (“warm area” W) of the oven door 1, which has a loading opening 11 of a receiving space or oven space 12 of an oven 13 that can be closed by the oven door 1 (see in more detail 6 ) directly. The intermediate panes 6, 7 are limited to this warm area W for thermal insulation.

Below the warm area W there is a lower cold area K, which is intended to be arranged to the side, here: below, the loading opening 11 when the oven door 1 is closed. The cold area K can be forced ventilated by means of a fan (not shown) so that a stream of cooling air flows through it when the fan is switched on. The forced ventilation can be carried out by means of a fan located in the oven door 1 (not shown) or a fan arranged in a body of the oven 13.

The cold area K is separated from the hot area W by a partition 14 which is formed at a lower edge of the frame 3 and extends over the entire width between the door profiles 2.

The outer sides of the door handle 10 and the door profiles 2 form an elongated guide 15 on each side for the sliding or rolling reception of a guide element (not shown) in order to be able to insert the oven door 1 into a body of the oven 13.

2 shows an oblique view of the back of the oven door 1 with the rear pane removed in greater detail. 3 shows the oven door 1 with the rear inner pane 8 removed in a rear view.

The oven door 1 also has a lighting device 16, by means of which the oven chamber 12 of the oven 13 can be illuminated (see in more detail 6 ). The lighting device 16 has a light source in the form of a light-emitting diode 17 on the left and right sides, to which a rod-shaped light guide 18 is connected. The left-hand part and the right-hand part can in particular be designed to have the same effect in terms of shape (eg mirror symmetry to a door center line).

The light-emitting diodes 17 are located in the cold area K so that they are sufficiently thermally protected even at high temperatures in the furnace chamber 12. This is because the light-emitting diodes 17 are firstly not directly exposed to the heat radiation emerging from the furnace chamber 12 and are also ventilated by the forced ventilation of the cold room K.

As a result, the light-emitting diodes 17 can also withstand temperatures of 400°C to 500°C in the furnace chamber 12 during pyrolysis operation without a significant reduction in their service life.

The light-emitting diodes 17 are arranged here on the left side or right side in a partial area of the lower cold area K, which extends up to 100 mm from a lower door edge 30 and up to 150 mm from a next door profile 2.

As also partially enlarged in 4 and 5 (Section A) shows the light-emitting diodes 17 are attached to respective supports 19, which in turn are glued to the front screen 4. The supports 19 can also serve as heat sinks and are preferably made of a material with good thermal conductivity, in particular with a thermal conductivity of more than 15 W/(m·K), e.g. aluminum. The supports 19, which also serve as heat sinks, can be surrounded by the cooling air flowing in the cold area K. The supports 19 can also provide a power connection for the light-emitting diode(s) 17.

For improved heat dissipation, the carriers 19 can have at least one cooling structure (not shown) on their outside, e.g. cooling fins, cooling pins, cooling fins, etc. The cooling structure can be integrally connected to the carrier 19 or, e.g., as a dedicated heat sink, can be firmly connected to the carrier 19, e.g., screwed or clamped to it or glued to it.

Alternatively or additionally, heat dissipation from the LEDs 17 may be achieved by a thermally well-conductive connection to the door profiles 2, e.g. by connecting the supports 19 to a respective door profile 2.

For a good thermal connection of the light-emitting diodes 17 with their respective carrier 19 serving as a heat sink, the light-emitting diodes can, for example, be clamped to the carrier 19 and/or attached to the carrier via a thermal interface material (TIM).

An intermediate piece 20 is arranged above each of the LEDs 17 and is thus optically connected downstream. The intermediate piece 20 serves to transmit the light emitted by the associated LED 17 To couple in light and to couple it out again in a targeted manner. The intermediate piece 20 has a truncated cone-shaped basic shape and has a dome-like, e.g. spherical cap-shaped recess (not shown) on a smaller lower cover surface facing the light-emitting diode 17, which at least essentially arches over the light-emitting diode 17, including laterally. The intermediate piece 20 therefore also serves as an optic or an optical element, here: for beam shaping.

Since the intermediate piece 20 is located entirely in the cold region K, it does not need to meet any special thermal requirements and may be made of a less thermally resistant material, e.g. transparent plastic. However, the intermediate piece 20 is not limited to this and may be made of glass, glass ceramic, etc. The intermediate piece 20 is also held on the carrier 19.

The light guide 18 is flatly connected to an upper, flat cover surface 21 of the intermediate piece 20, which faces away from the recess. Both the intermediate piece 20 and the light guide 18 conduct light by means of total internal reflection (TIR), i.e. they are designed as TIR bodies. Light entering the spherical cap-shaped recess is radiated through the upper cover surface 21 into the light guide 18 if the refractive indices of the light guide 18 and the intermediate piece 20 match sufficiently, in particular if they are made of the same material (e.g. glass). To improve light transmission, at least one optical transition layer (not shown) can be provided on the upper cover surface 21.

The light guides 18 are each arranged vertically in the oven door 1 and parallel to the door profiles 2. They extend from the intermediate piece 20 to an upper crosspiece 22 of the frame 3. The light guide 18, the intermediate piece 20 and the light-emitting diode 17 of a respective side are arranged in series or collinearly with one another, which enables a high photometric lighting efficiency. For this purpose, a length of the respective light guide 18 is less than a height of the oven door 1. The length of the light guides 18 is the same here.

In order to guide the light guides 18 through the partition 14, the partition has two light-passing openings 23 through which a respective light guide 18 extends, so that light generated by the light-emitting diodes 17 in the light guides 18 can be guided through the partition 14.

Since the section of the light guide 18 above the partition 14 is located in the warm area W of the oven door 1, it is preferred that the light guide 18 consists of a thermally resistant material which, in particular during pyrolysis, withstands temperatures in the receiving space of e.g. 400°C to 500°C without damage. This material is preferably glass or glass ceramic.

The light guide 18 and the intermediate piece 20 can be made in one piece, e.g. from glass, for easier assembly. A light guide 18 then has in particular a section which corresponds to the intermediate piece 20 in terms of design and/or function, but is integrated into the light guide 18. Alternatively, for example, the intermediate piece may be made of plastic (e.g. polycarbonate, PMMA or epoxy resin) and the light guide 18 may be made of glass or similar. The light guide 18 may also be made of plastic.

The light guides 18 are arranged and designed to radiate light coupled into them through the loading opening 11 into the furnace chamber 12. 6 shows a top view of a possible light of a light emission pattern M radiated by the two light guides 18 into the oven chamber 12. The light emission pattern M can illuminate a respective shelf level almost completely and extremely evenly. Because the light guides 18 extend over the entire height of the frame 3 and thus a visible area of the oven door 1, all shelf levels can be illuminated in this way, even if the oven chamber 12 is occupied by shelf supports or the like. The light guides 18 have the further advantage that they can serve as a heat barrier and can thus shield the adjacent door profile 2 against heat from the oven chamber 12. This can be particularly advantageous for door profiles 2 made of plastic.

To form the oven chamber 12, the oven 13 has a muffle 27 that is open on one side through the loading opening 11. The muffle 27 is separated from a housing 13a of the oven 13 by a thermal insulation 24. The oven door 1, in its closed state shown, rests laterally on a flange 25 of the muffle 27 that surrounds the loading opening.

The two light guides 18 are arranged such that they are located at least partially in the warm area W of the oven door 1, which enables wide-angle light to enter the oven chamber 12. For high lighting efficiency and good thermal shielding of the front pane 4, the light guides 18 are arranged here between the inner pane 8 and the adjacent intermediate pane 7, e.g. since the intermediate panes 6, 7 can then be made thick without influencing the lighting.

A thickness of the circular-cylindrical light guide 18 is preferably 5 mm to 30 mm, but is not limited thereto. A cross-sectional profile of the light guide 18 is curved at least in sections and can be circular-cylindrical, circular-segment-shaped or oval, for example. For broad light emission, a curved or more strongly curved region of a lateral surface 26 of the light guide 18 preferably faces the furnace chamber 12.

For a targeted emission of light from the light guides 18, in particular directly into the furnace chamber 12, these can be designed or prepared accordingly, at least in some areas, in particular on their surface. For example, a light guide 18 can be masked where light emission is to be prevented. The light guide 18 can thus be coated in a light-absorbing manner or, preferably for a high light output, in a reflective manner.

Alternatively or additionally, as in 7 shown, a light guide 18 can be roughened or otherwise suitably microstructured in an area 18a where light emission is to be prevented or suppressed. This microstructuring, in particular roughening, causes diffuse reflection of the light into the light guide 18, often at an angle that causes increased light emission from the light guide 18 at the location of the light guide 18 illuminated by the back reflection. Consequently, light is emitted to an increased extent from a non-roughened (smooth) area 18b of the light guide 18. Roughening can be caused, for example, by sandblasting or etching and makes the roughened surface area appear milky or diffuse.

To reduce light losses, an upper, free covering surface of the light guides is also designed to be opaque.

The light guide 18 is masked (designed or prepared) for a uniform light emission over its length, preferably at a circumferential angle α that is constant over its length, around its longitudinal axis L for a targeted light emission. The circumferential angle α is preferably between approximately 45° and approximately 270°, so that in a further development, light can emerge in an increased manner in the complementary circumferential angle range between approximately 315° and approximately 90° (at which the surface of the light guide 18 is in particular smooth and uncoated).

Alternatively, the light guide may have several regions 18a spaced apart along its length, which are arranged in a row, for example. This allows a light intensity or a luminous flux to be varied along the length and, for example, concentrated on certain height regions, e.g. on regions between the shelf supports of an oven.

8 shows a light guide 18, to which an intermediate piece is adjacent at an angle at the bending angle β. The lighting device 16 can thus extend essentially over the entire height of the oven door 1. The bending angle β is here between 90° and 180°. Alternatively, the light guide can be angled at the bending angle β.

For a further increase in the photometric lighting efficiency or light yield, a reflector 28 can be provided on each of the light guides 18, which partially surrounds the light guide 18, in particular over its longitudinal section radiating into the furnace chamber 12 (here: the section protruding into the heat area W). 9 a tube-like or tubular reflector 28 with a circular sector-shaped profile. The reflector 28 partially surrounds the light guide 18 (which serves as a light emitting element) in a circumferential direction. The reflector 28 surrounds the light guide 18 in a longitudinal section outside the cold room K or inside the warm room W.

A light transmission opening 29 formed in a lateral surface 28a of the reflector 28 has an opening angle γ in relation to a longitudinal axis L of the light guide 18 of here γ = 90°. The light transmission opening 29 points in the direction of the furnace chamber 12. The furnace chamber 12 can be illuminated in a targeted manner by the orientation and size of the opening 29.

The complementary circumferential angle (1-α) with α = 270° of the light guide 18 corresponds to the opening angle γ of the light exit opening 29, whereby the surface area 18a of the light guide 18 that prevents or suppresses the light exit is also directed towards the reflector 28. The area 18b of the light guide 18 that emits more light is similarly directed towards the light exit opening 29. In this way, a high proportion of the light emitted by the light guide 18 is emitted directly from the light exit opening 29.

The reflector 28 and the light guide are aligned parallel to one another in the longitudinal direction. Light radiated from the light guide 18 onto the reflector 28 can be reflected by the reflector 28 through the light transmission opening 29 into the furnace chamber 12. Light emerging from the light guide 18 can therefore be radiated directly through the light transmission opening 29 or indirectly via the reflector 28 into the furnace chamber 12.

As a further advantage, in addition to the light guide 18, the reflector 28 can also serve as a heat shield, which thermally shields the door profile 2 from the oven chamber. This can be particularly advantageous for door profiles 2 made of plastic.

The reflector 28 can be specularly reflective on its side facing the light guide 18 or, preferably for uniform light emission, diffusely reflective.

The reflector 28 can simultaneously serve as a carrier for the light guide 18.

The reflector 28 can be in one piece or in multiple parts. In a multi-part structure, different parts can be provided for different functions, e.g. for reflecting, carrying, positioning, etc., which supports standardization of components.

For lower temperatures, the reflector 28 can be, for example, a plastic body with a reflective coating. For higher temperatures, the reflector 28 can be, for example, a reflective coated or a shiny polished metal body. A reflective coating can comprise, for example, aluminum and/or chrome. For example, the reflector 28 can be an iron or steel sheet coated with high-gloss aluminum.

10 shows a further possible embodiment of the lighting device 16 with a reflector 28. Several light-emitting diodes 17 arranged in a row at a distance along the longitudinal axis L of the reflector 28 are now present as light-emitting elements. The light-emitting diodes 17 are directed into the reflector 28 and thus essentially only irradiate the reflector 28. The light-emitting diodes 17 are partially surrounded by the reflector 28 in the circumferential direction. The light-emitting diodes 17 are suspended from thin crossbars 31, via which they can also be supplied with power.

For thermal protection of the LEDs 17 against heat radiation emanating from the furnace chamber 12, heat shields 32 are attached to the cross struts 31 behind the LEDs 17, which act as heat-reflecting screens.

The reflector 28 is designed to be diffusely reflective for uniform light emission.

Of course, the present invention is not limited to the embodiment shown.

The light guide and/or the reflector can also be curved or angled in terms of their length, i.e., not just straight.

list of reference symbols

1

oven door

2

door profile

3

Frame

4

windshield

5

bracket

6

intermediate disc

7

intermediate disc

8

inner pane

9

essay

10

door handle

11

loading opening

12

furnace room

13

oven

13a

Housing

14

separation

15

guide

16

lighting equipment

17

light source, light-emitting diode

18

light guide

18a

roughened area

18b

smooth area

19

carrier

20

intermediate piece

21

deck area

22

crosspiece

23

light transmission openings

24

thermal insulation

25

flange

26

surface of the light guide

27

muffle

28

reflector

28a

surface of the reflector

29

light transmission opening

30

door edge

31

cross brace

32

heat shield

A

neckline

K

cold area

L

longitudinal axis

M

light emission pattern

W

warm area

α

circumferential angle range

β

bend angle

γ

opening angle

Claims (14)

Household appliance door (1) in the form of an oven door for closing a loading opening (11) of a receiving space (12) of a household appliance (13) in the form of an oven, wherein - the household appliance door (1) has at least two lighting devices (16), each with at least one light emitting element (17, 18) for illuminating the receiving space (12), and - the lighting device (16) has at least one reflector (28) which partially surrounds at least one light emitting element (17, 18) illuminating the reflector (28), - the reflector (28) is a vertical reflector (28) which is tubular with at least one light exit opening (29) formed in a lateral surface (28a), which is directed into the receiving space (12) and extends over the entire length of the lateral surface (28a), characterized in that - the household appliance door (1) has two laterally arranged door profiles (2), which are connected to one another by a rectangular frame (3) and to which at least one front pane (4) and one inner pane (8) are fastened, - the reflectors (28) run parallel to a respective door profile (2) and are arranged between the inner pane (8) and an adjacent pane (5-7), - the reflectors (28) extend at least over a height of the loading opening (11) and - the reflectors (28) thermally shield a respective adjacent, laterally arranged door profile (2). Household appliance door (1) after claim 1 , characterized in that the door profiles (2) are made of plastic. Household appliance door (1) according to one of the preceding claims, characterized in that at least one intermediate pane (6, 7) is additionally fastened to the door profiles (2) and the reflectors (28) are arranged between the inner pane (8) and an intermediate pane (6, 7) adjacent thereto. Household appliance door (1) according to one of the preceding claims, characterized in that the at least one light emitting element (17, 18) illuminating the reflector (28) has at least one light guide (18). Household appliance door (1) after claim 4 , characterized in that the light guide (18) has at least one surface region (18a) at which light exit is prevented or suppressed, and at least one surface region (18b) which is provided for light emission, wherein the at least one surface region (18a) preventing or suppressing light exit is directed towards the reflector (28). Household appliance door (1) after claim 1 , characterized in that the at least one light emitting element (17, 18) illuminating the reflector (28) has at least one light source (17) directed towards the reflector (28). Household appliance door (1) after claim 6 , characterized in that the at least one light source (17) has a heat shield (32) on a side facing away from the reflector (28). Household appliance door (1) according to one of the preceding claims, characterized in that the light exit opening (29) has a circumferential angle γ between approximately 90° and approximately 270°. Household appliance door (1) according to one of the preceding claims, characterized in that the reflector (28) represents a holder for at least one further element of the lighting device (16). Household appliance door (1) according to one of the preceding claims, characterized in that at least one reflector (28) extends parallel to a lateral door profile (2) at a distance of up to 150 mm. Household appliance door (1) according to one of the preceding claims, characterized in that - the lighting devices (16) each have at least one light guide (18) and at least one light source (17), the light of which can be coupled into the at least one light guide (18), and - the reflector (28) partially surrounds the light guide (18) circumferentially. Household appliance door (1) after claim 11 , characterized in that the light guide (18) consists of a glass-like material. Household appliance (13) in the form of an oven with a household appliance door (1) in the form of an oven door, characterized in that the household appliance door (1) is a household appliance door (1) according to one of the preceding claims. Household appliance (13) after claim 13 , characterized in that the household appliance (13) is a pyrolysis-capable household appliance (13).

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