Household appliance door with lighting fixture

Abstract

A household appliance door (1) in the form of an oven door for closing a loading opening (11) of a receiving chamber (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 chamber (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 vertically oriented reflector (28) which is tubular in shape with at least one light-exit opening (29) formed in a lateral surface (28a) which is directed into the receiving chamber (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 each other 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 the 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 domestic appliance door in the form of a furnace door for closing a charging opening of a receiving space of a domestic appliance, wherein the domestic 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 a furnace door.EP 1 995 522 B1 discloses a furnace, inside the furnace door of which lighting means for illuminating a furnace muffle that can be closed by the furnace door are provided. These illumination means have a plurality of light sources which emit their light in a directly focused manner in the direction of the furnace muffle. The light sources can be light-emitting diodes arranged in series and directed to their light in each case the furnace muffle. For this purpose, it is shown to fasten the light-emitting diodes to a left-hand region and to a right-hand region of the oven door in each case on a sheet metal carrier, wherein an alignment of the light-emitting diodes is achieved by means of a corresponding local alignment of the sheet metal carrier. The oven door can be cooled by natural ventilation. However, the oven door is comparatively complex in construction. The light-emitting diodes are also only insufficiently protected from high temperatures, as occur, for example, during pyrolysis operation.In addition, the publication US 2009 / 0 316 385 A1 discloses a furnace lamp comprising an LED assembly or assemblies which are optically coupled to an optical guide element. The luminaire also includes a mounting bracket and a pair of electrical leads for connecting the LED luminaire to an external voltage source. The LED package consists of an LED mounted on a printed circuit board containing additional circuitry for powering the LED and a heat sink for removing heat from the LED. The mounting bracket may be attached to a door of the oven room to support the LED lamp adjacent a side light window. The mounting bracket has a slot adjacent the window for transmitting the light from the LED through the light guide into the oven cavity. By positioning the luminaire outside the oven space and next to the side light window, the LED can be operated within the required temperature limits.In addition, the publication DE 10 2005 045 367 A1 discloses an interior lighting device for a cooking appliance having a lighting unit for radiating illumination 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 with a non-dangerous low-voltage power supply in a power-saving manner, it is proposed that the lighting unit comprises at least one light-emitting diode.In addition, the document DE 38 27 528 A1 discloses a device for illuminating a cooking chamber, wherein a lamp for protection against high temperatures and aggressive influences is installed between two protective glass panes.It is the object of the present invention to overcome the disadvantages of the prior art at least partially and in particular to provide a simply constructed domestic door equipped with at least one lighting means, in which the lighting means can be protected from high temperatures in an improved manner.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 domestic appliance door in the form of a furnace door for closing a charging opening of a receiving space, wherein the domestic appliance door in the form of a furnace door has at least two lighting devices each with at least one light emission element for illuminating the receiving space. The illumination device has at least one reflector which partially surrounds at least one light-emitting element which illuminates the reflector. This increases a light yield and enables a multiple-form light alignment and consequently a more targeted illumination of the receiving space.Because the reflector surrounds the at least one light-emitting element (circumferentially) only partially, at least one light passage opening is produced in the reflector, through which light can emerge from the reflector. The light emerging through the at least one light passage opening can either be transmitted directly by the at least one light emission element and / or transmitted reflected by the reflector. The at least one light passage opening in the region of a light emission 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 outlet opening formed in a lateral surface. The light exit opening is directed into the receiving space. A large-area reflection with a well-defined beam shaping can thus be achieved, which keeps light losses low.The profile of the tubular reflector can be, for example, sector-wise circular cylindrical, oval, angular and / or free-form.According to the invention, the light outlet opening extends over substantially the entire length of the lateral surface of the reflector.According to the invention, the domestic appliance door has two door profiles arranged laterally, which are connected to one another by a rectangular frame and to which at least one front pane and one inner pane are fastened,According to the invention, the reflectors run parallel to a respective door profile and are arranged between the inner pane and a pane adjacent thereto,According to the invention, the reflectors extend at least over a height of the charging opening. The reflector can be arranged in particular between the receiving space and the door profile. Such a reflector can be in particular a reflector standing vertically, If the light guide represents the light emission element, the light guide can also serve as a heat shield, so that the door profile is shielded twice thermally from the receiving space.According to the invention, the reflectors thermally shield a respectively adjacent door profile. The reflector can thus serve in particular as a heat shield, in particular in order to thermally shield a door profile from the receiving space.In another embodiment, the door profiles are made of plastic.In another embodiment, at least one intermediate pane is additionally fastened to the door profiles and the reflectors are arranged between the inner pane and an intermediate pane adjacent thereto.In another configuration, 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 reflected at least partially by means of the reflector into the receiving space.Light of at least one light source can be coupled into an optical waveguide. The light guide is consequently arranged and configured to forward the light coupled into it and to radiate it (directly and / or indirectly) into the receiving space. By providing the at least one light guide, particularly uniform and large-angle illumination of the receiving space can be achieved in a simple manner. A light guide can also be designed to be particularly thermally insensitive, for example when formed from glass or glass ceramic.In one configuration, the light guide has at least one surface region at which light leakage is prevented or suppressed and at least one surface region which is provided for light emission, wherein the at least one surface region which prevents or suppresses light leakage is directed towards the reflector. This makes selective illumination of the receiving space easier in a compact manner and suppresses a portion of the light reflected by means of the reflector. Alternatively, the light guide may selectively emit light onto the reflector in order to obtain a more directional light emission pattern.In a special embodiment, the at least one light emission preventing or suppressing surface region of the light guide is masked, in particular coated or roughened in a light-impermeable manner. For example, a light guide can be coated in a light-absorbing manner or, preferably, in a reflective manner for a high luminous efficiency, where light leakage is to be prevented. Roughening or other copolymerization can be effected, for example, by sandblasting or etching and makes the roughened surface region appear milky or diffuse. Roughening or other copolymerization causes diffuse reflection of light into the light guide, often at an angle that causes enhanced light emission from the light guide at the location of the light guide illuminated by the reflection. Consequently, in particular, increased light is emitted from an uncoated or roughened (i.e. smooth) region of the light guide.It is a development advantageous for light emission that is uniform over its length that the light guide is designed or prepared for targeted light emission at a circumferential angle α about its longitudinal axis L that is constant over its length. However, the invention is not limited thereto, and the circumferential angle α may 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 development, more light can emerge in the circumferential angle range complementary thereto between approximately 315° and approximately 90° (at which the surface of the light guide is in particular smooth and uncoated). The light guide can also have regions spaced apart over its length, which regions have, for example, a circumferential angle α which is the same as one another. The regions can be arranged in a row or, for example, also offset angularly about the longitudinal axis.In one embodiment, the light guide is made of a vitreous material (glass, glass ceramic or the like). The glass is preferably borosilicate glass. Vitreous material is highly temperature resistant and typically transparent. An optical property can be changed easily and precisely by adding fillers. Thus, the light guide may be configured as a diffusely scattering light guide. Moreover, vitreous material is comparatively inexpensive, versatile and easily retreatable in its surface.Alternatively, the light guide may consist 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 be, in particular, a light guide which can guide light within its material or body ("light guide body"). The light guide is in particular a body which can guide the light by means of total internal reflection (TIR body). The light guide is in particular a solid body.In another development, a thickness of at least one light guide is preferably between 5 mm and 30 mm. However, the thickness is not limited thereto.It is also a refinement that a cross-sectional profile of at least one light guide is curved at least in sections and can be embodied in particular in a circular, circular segment-shaped or oval manner. For a broad light emission, a curved or a more strongly curved region of a lateral surface of the light guide preferably faces the receiving space. However, the cross-sectional profile is not limited thereto, but can also be angular and / or free-formed, for example.The light guide is preferably formed in a straight line, but can also be curved in principle.In another configuration, the at least one light-emitting element illuminating the reflector has at least one light source directed towards the reflector. The light-emitting element therefore radiates substantially only onto the reflector and illuminates the receiving space only indirectly. Thus, at least one comparatively warm light emission surface of the at least one light source can be protected from direct heat irradiation from the receiving space. The reflector also enables more versatile beam shaping and, in particular in the case of a diffuse reflector, more uniform and large-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. Thus, the light source can be protected even more effectively against heat radiation from the receiving space.The reflector can be specular and / or diffuse reflective. Diffuse reflection supports uniform light emission of the reflector, specular reflection on the other hand supports directivity.In another embodiment, the light exit opening has an opening angle γ between approximately 90° and approximately 270°. For loss-free illumination when using a light guide as the light emission element, it is advantageous that a complementary circumferential angle (1-α) of the light guide corresponds at least approximately to the opening angle γ of the light outlet opening.In addition, it is an embodiment that the reflector constitutes a holder for at least one further element of the illumination device. This allows simplified assembly with low position tolerances to be achieved. The further element can be, for example, a light guide and / or a carrier for at least one light source.The reflector can be in one part or in multiple parts. In a multi-part construction, different parts can be provided for different functions, e.g. for reflecting, supporting, positioning, etc., which supports a standardization of components and also their more uniform mounting.For lower temperatures, the reflector can be, for example, a reflectively coated plastic body. For higher temperatures to be maintained, the reflector can be, for example, a metal body with reflective coating or a polished lustrous coating. A reflective coating can comprise, for example, aluminum and / or chromium.The reflector can furthermore be configured as a heat sink. For this purpose, the reflector can have at least one cooling structure (cooling ribs, cooling pins, etc.), in particular on a side facing away from the at least one light-emitting element.In another configuration, at least one reflector, in particular with the at least one light-emitting element illuminating it, is arranged between an inner pane and a pane adjacent thereto (e.g. a front pane or an intermediate pane). This enables a particularly high illumination efficiency. In addition, if at least one intermediate pane is present, good thermal shielding of the front pane is made possible, since the at least one intermediate pane can then be made thick without influencing the illumination.In yet another embodiment, at least one reflector, in particular with the at least one light-emitting element illuminating it, extends at least over a height of the feed opening. Thus, the receiving space can be illuminated over its entire height, even when at least one insertion plane or the like is occupied. The reflector is preferably oriented vertically.In principle, one, two or even more reflectors, in particular with at least one respective light emission element, can be provided. At least one reflector can be configured and arranged for illuminating a plurality of (in particular all) insertion planes of the receiving space, in particular a reflector which is upright.A reflector, in particular having at least one respective light emission element, can be arranged in particular vertically or horizontally. A vertical arrangement enables illumination over the height of the receiving space, in particular over a plurality of insertion planes. A reflector which is upright preferably runs parallel to a door profile of the domestic appliance door. In order to provide the largest possible see-through 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 of a right edge (reflector arranged on the right side) of a viewing window of the domestic appliance door.In particular, two reflectors with at least one respective light emission element may be provided for illuminating an insertion plane. Thus, shadow formation in the accommodation space can be reduced. A reflector arranged on the left and a reflector arranged on the right can be designed and / or arranged in particular mirror-symmetrically to a door central axis in order to support uniform illumination of the receiving space.Alternatively, at least one reflector may be configured and arranged for illuminating only one insertion plane in each case. For this purpose, the reflector can be arranged in particular horizontally in order to enable uniform illumination over the width of the receiving space. In order to provide the largest possible see-through 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 domestic appliance door.In a further embodiment, the light guide is preceded by an intermediate piece into which light of at least one light source can be coupled and which forwards the coupled-in light to the light guide. The intermediate piece enables effective light coupling from the at least one light source and consequently a high light yield.It is also an embodiment that the intermediate piece is or comprises an optical element. This allows a particularly versatile beam guidance to be achieved, in particular for a high luminous efficiency.In another embodiment, at least one light guide, the associated intermediate piece and the at least one light source that irradiates light into the intermediate piece are arranged collinearly, which enables a high photometric illumination efficiency. For this purpose, a length of the respective light guide is in particular less than a height of the oven door.In another embodiment, at least one light guide protrudes into a cold region of the household appliance door and the at least one light source (associated light, i.e. light radiating into this light guide directly or indirectly, e.g. via an intermediate piece) is also located in the cold region. The cold region is provided for the purpose of being arranged laterally of the charging opening in a closed state of the domestic appliance door. A cold region can consequently be understood in particular as a region of the domestic appliance door which, in the closed state of the domestic appliance door, does not cover the latter. By arranging the at least one light source in the cold region, it can be kept at a low thermal level in the receiving space even at high temperatures. In particular, the light source is not exposed to any direct thermal radiation. Consequently, a particularly long service life of the lighting device can be achieved, and indeed even if an associated domestic appliance is capable of pyrolysis.For this purpose, the intermediate piece is also preferably accommodated in the cold region, in particular in the case of pyrolysis-capable domestic appliances. In a development which is particularly suitable for this purpose, the intermediate piece consists of plastic and the light guide consists of glass. Thus, low cost and versatile light coupling and light transmission is provided. The intermediate piece and the light guide can alternatively, for example, both consist of the same material, for example of glass or plastic (for example polycarbonate, PMMA, etc.), in particular be formed in one piece. This simplifies production.In general, the cold region can be, in particular, that cold region which is located on that side of the domestic appliance door on which the latter is pivotable or has at least one door hinge. Such a cold region is comparatively large, so that a sufficient, non-compact installation space is available for accommodating the at least one light source.In one configuration, the cold region is a lower cold region. A lower cold region can be understood in particular as a cold region which, in the closed state of the domestic appliance door, is arranged below the charging opening. Such a cold area is available in particular in the case of downwardly opening doors such as oven doors.Alternatively, the cold region, in particular in the case of a laterally opening or laterally pivotable domestic appliance door, can be a lateral cold region (for example for refrigerators or microwave ovens) or, in particular in the case of an upwardly opening or upwardly pivotable domestic appliance door, can be an upper cold region (for example in the case of a high-level built-in appliance).In another embodiment, at least one light guide extends parallel to a lateral door profile at a distance of up to 150 mm. In one development, the at least one light source is arranged in a partial region of the lower cold region, which extends up to 100 mm from a lower door edge and / or up to 150 mm from lateral door profiles.In yet another configuration, the at least one light source comprises at least one semiconductor light source. A semiconductor light source is particularly long-lived, 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 a plurality of light emitting diodes are present, these can illuminate in the same color or in different colors. A color may be monochrome (e.g., red, green, blue, etc.) or multi-chrome (e.g., white). A plurality of light emitting diodes may generate mixed light; e.g., 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 remote from the light-emitting diode ("remote phosphor"). The at least one light emitting diode can be present in the form of at least one individually packaged light emitting diode or in the form of at least one LED chip. Multiple LED chips may be mounted on a common substrate ("submount"). The at least one light emitting diode can be equipped with at least one dedicated and / or common optical unit for beam guidance, e.g. at least one Fresnel lens, collimator, and so forth. 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 generally also be used. Alternatively, the at least one semiconductor light source can have, for example, at least one diode laser.The domestic appliance door can have at least one electrical connection to the associated (remaining) domestic appliance for supplying power to the at least one light source. When using at least one light emitting diode, an associated driver can be present in the domestic appliance door, in particular in the cold region, or alternatively in the (remaining) domestic appliance.In addition, it is an embodiment that the domestic appliance door can be forcibly ventilated. As a result, a temperature in the domestic appliance door is lowered further, which extends a service life of its components and improves user safety against high temperatures. In one refinement, at least the cold region can be forcibly aerated. The light sources generating waste heat can thus be cooled particularly effectively.In addition, it is an embodiment that the at least one light source is connected to at least one heat sink in a thermally conductive manner. 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 simple assembly. The heat sink or holder can be fastened to a reflector for low-cost production, for a reduction of assembly tolerances and for simple assembly and in particular can be pre-mounted thereon.In another embodiment, the cold region is separated from a hot region covering the charging opening in a closed state of the domestic appliance door by means of a separation, and the separation has at least one light transmission opening for transmitting light generated by means of the at least one light source. This facilitates light guidance between the cold region and the warm region. The partition may be at least partially air-permeable in order to allow a cooling air flow between panes of the household appliance door. In another development, at least one light guide extends through a light passage opening. In this way, elements upstream of the light guide can be accommodated in the cold region, where they are thermally protected.It is furthermore an embodiment that the household appliance door is a cooking appliance door, in particular oven door. The associated domestic appliance is consequently an oven, in particular an oven, the receiving space of which can also be referred to as an oven space or (in the case of an oven) as a baking tube. In particular in the case of a furnace, in particular a baking oven, pyrolysis can be carried out and effective illumination is required on account of the comparatively large receiving space (furnace space).In another embodiment, the illumination 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 circumferentially.In addition, it is an embodiment that the light guide consists of a vitreous material.The object is also achieved by a domestic appliance in the form of a furnace with at least one domestic appliance door in the form of a furnace door as described above.In one configuration, the domestic appliance is a pyrolyzing-capable domestic appliance.The household appliance produces the same advantages as the household appliance door and can also be designed analogously.The household appliance can fall in particular into the area of the "white goods" and serve in particular for completing domestic work such as cooking, baking, washing, cleaning etc. The household appliance may be a large household appliance (e.g. comprising a refrigerator, a freezer, a freezer, an electric oven, a washing machine, a dishwasher and a tumble dryer) or a small household appliance (e.g. comprising a microwave appliance).The household appliance can be, in particular, a kitchen appliance. It is particularly preferred that the household appliance is a cooking appliance (e.g. comprising an oven and / or a steam cooker), in particular an oven.In the following figures, the invention is described in more detail schematically with reference to exemplary embodiments. For the sake of clarity, identical or identically acting elements can be provided with identical reference numerals. FIG. 1 shows an exploded view from obliquely behind of an oven door; FIG. 2 shows a view obliquely from the rear of the oven door with the rear pane removed; FIG. 3 shows the oven door from FIG. 2 in a rear view; FIG. 4 shows a detail from FIG. 2 in the region of a light source; FIG. 5 shows a detail from FIG. 3 in the region of the light source; FIG. 6 shows a sectional illustration of a baking oven equipped with the baking oven door in plan view with an associated light emission pattern; FIG. 7 shows an oblique view of a further possible light guide of the oven door; FIG. 8 shows a side view of yet another possible light guide of the oven door; FIG. 9 shows a sectional illustration in plan view of a reflector with a light emission element in the form of a light guide; and FIG. 10 shows a sectional illustration in plan view of a reflector with a light-emitting element in the form of a light source.FIG. 1 shows an exploded view from obliquely behind of a basic structure of a domestic appliance door in the form of an oven door 1, the oven door 1 having two laterally arranged door profiles 2 which are connected to one another by a rectangular frame 3. The frame 3 represents a lateral delimitation of a viewing window.A front pane 4 is placed on the front side of the door profiles 2. For this purpose, the front pane can have a plurality of holders 5 which are adhesively bonded to the front pane 4 and can engage in the door profiles 2. Optionally, at least one intermediate pane can be inserted between the door profiles 2, 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 likewise be fastened to the door profiles 2, for example, by fasteners 5 glued thereto. The oven door 1 is covered over its entire width on the top by a cover 9 which has a door handle 10.The frame 3 delimits, in a view from the front or the rear, at least approximately an area ("warm area" W) of the oven door 1, which directly covers a charging 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 this respect more precisely FIG. 6 ). The intermediate disks 6, 7 are limited to this warm region W for thermal insulation.Below the warm region W is a lower cold region K which is provided for being arranged laterally, here: below, of the charging opening 11 in a closed state of the oven door 1. The cold region K can be forcibly ventilated by means of a fan (see FIG. ), so that a cooling air stream flows through it when the fan is switched on. The forced ventilation can be carried out by means of a fan (see above) located in the oven door 1 or a fan arranged in a body of the oven 13.The cold region K is separated from the heat region W by means of 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 of the door profiles 2 form on each side an elongate guide 15 for the sliding or rolling reception of a guide element (see FIG. ) in order to be able to push the oven door 1 into a body of the oven 13.FIG. 2 shows an oblique view of a rear side of the oven door 1 with the rear pane removed to a higher degree of accuracy. FIG. 3 shows the oven door 1 in a rear view with the rear inner pane 8 removed.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 this respect more precisely FIG. 6 ). The lighting device 16 has on the left and on the right a light source in the form of a light-emitting diode 17 which is adjoined in each case by a rod-shaped light guide 18. The left-side part and the right-side part can be configured to have the same effect, in particular in terms of shape (e.g. mirror-symmetrical to a door center line).The light-emitting diodes 17 are located in the cold region 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 thermal radiation emerging from the furnace chamber 12 and are additionally ventilated by the forced ventilation of the cold chamber 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 a pyrolysis operation without a significant reduction in their service life.The light-emitting diodes 17 are arranged here in each case on the left or right side in a partial region of the lower cold region 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 is also shown enlarged in detail in FIGS. 4 and 5 (detail A), the light-emitting diodes 17 are fastened on respective carriers 19, which in turn are adhesively bonded to the front pane 4. The carriers 19 can also serve as heat sinks and for this purpose preferably consist of a material of good thermal conductivity, in particular with a thermal conductivity of more than 15 W / (m·K), e.g. aluminum. The carriers 19 which also serve as cooling bodies can be surrounded by the cooling air flow flowing in the cold region K. The carriers 19 can furthermore provide a power connection for the light emitting diode(s) 17.For improved heat dissipation, the carriers 19 may have at least one cooling structure (see FIG. ) on their outer side, e.g. cooling ribs, cooling pins, cooling fins, etc. The cooling structure may be integrally connected to the carrier 19 or may be firmly connected to the carrier 19, e.g. screwed or clamped thereto or glued thereto, e.g. as a dedicated cooling body.Alternatively or additionally, heat dissipation from the light emitting diodes 17 may be achieved by a thermally highly conductive connection to the door profiles 2, for example by means of a connection of the carriers 19 to a respective door profile 2.For a good thermal connection of the light emitting diodes 17 to their respective carrier 19 serving as a cooling body, the light emitting diodes can be clamped to the carrier 19 for example and / or fastened to the carrier via a thermal interface material (TIM).An intermediate piece 20 is arranged downstream of the light-emitting diodes 17 above each and thus optically downstream. The intermediate piece 20 serves to couple in light emitted by the associated light-emitting diode 17 and to couple it out again in a targeted manner. For this purpose, the intermediate piece 20 has a frustoconical basic shape and has, on a smaller lower cover surface facing the light emitting diode 17, a dome-like, for example spherical-dome-shaped, cutout (see FIG. ), which bulges over the light emitting diode 17 at least substantially, and specifically also laterally. The intermediate piece 20 thus also serves as an optical unit or an optical element, here: for beam shaping.Since the intermediate piece 20 is located completely in the cold region K, it does not need to meet any particular thermal requirements and may consist of a material which is less thermally resistant, for example of transparent plastic. However, the intermediate piece 20 is not limited thereto, and may be made of, for example, glass, glass ceramic, etc. The intermediate piece 20 is likewise held on the carrier 19.The light guide 18 adjoins a planar upper cover surface 21 of the intermediate piece 20 facing away from the cutout. Both the intermediate piece 20 and the light guide 18 conduct light by means of total internal reflection (TIR), are therefore configured as TIR bodies. Light entering at the spherical dome-shaped recess is radiated into the light guide 18 through the upper cover surface 21 if the refractive indices of the light guide 18 and intermediate piece 20 sufficiently coincide, in particular in the case of the same material (e.g. glass). To improve a transmission of light, at least one optical transition layer (see FIG. ) 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 cross piece 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 respect to one another, which enables a high photometric illumination efficiency. For this purpose, a length of the respective light guide 18 is here less than a height of the oven door 1.For the passage of the light guides 18 through the partition 14, the partition has two light passage openings 23, through which a respective light guide 18 extends, so that light generated by the light-emitting diodes 17 can be guided in the light guides 18 through the partition 14.Since the section of the light guides 18 above the partition 14 is located in the warm region 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, exceeds temperatures in the receiving space of, for example, 400° C. to 500° C. without being damaged. This material is preferably glass or glass ceramic.The light guide 18 and the intermediate piece 20 can be formed in one piece, e.g. from glass, for a simpler assembly. A light guide 18 then has in particular a section which corresponds in terms of shape and / or function to the intermediate piece 20, but is integrated into the light guide 18. Alternatively, for example, the intermediate piece may consist of plastic (e.g. of polycarbonate, PMMA or epoxy resin) and the light guide 18 may consist of glass or the like.The light guides 18 are arranged and configured to radiate light coupled into them through the feed opening 11 into the furnace chamber 12. FIG. 6 shows in plan view a possible light of a light emission pattern M which is radiated into the furnace chamber 12 by the two light guides 18. The light emission pattern M can illuminate a respective insertion plane almost completely, highly uniformly. Due to the fact that the light guides 18 extend over the entire height of the frame 3 and thus over a visible area of the oven door 1, all insertion planes can be illuminated in this way, namely even when the oven chamber 12 is occupied by insertion carriers or the like. The light guides 18 have the further advantage that they can serve as a thermal barrier and thus can shield the adjacent door profile 2 from heat from the oven chamber 12. This can be advantageous in particular for door profiles 2 made of plastic.The oven 13 has a muffle 27 open on one side through the charging opening 11 to form the oven chamber 12. The muffle 27 is separated from a casing 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 surrounding the charging opening in a circumferential manner.The two light guides 18 are arranged such that they are situated at least partially in the warm region W of the oven door 1, which enables broad-angle light irradiation into the oven chamber 12. For high illumination efficiency and good thermal shielding of the front pane 4, the light guides 18 are arranged here between the inner pane 8 and the intermediate pane 7 adjacent thereto, e.g. since the intermediate panes 6, 7 can then be made thick without influencing the illumination.A thickness of the circular cylindrical light guides 18 here is preferably 5 mm to 30 mm, but is not limited thereto. A cross-sectional profile of the light guides 18 is curved here at least in sections and can be formed, for example, in the shape of a circular cylinder, a segment of a circle or an oval. For a broad light emission, a curved or a 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 the light from the light guides 18, in particular directly into the furnace chamber 12, these can be designed or prepared accordingly at least in regions, in particular on their surface. For example, a light guide 18 can be masked where light leakage is to be prevented. Thus, the light guide 18 can be light-absorbing or reflectively coated there, preferably for a high light yield.Alternatively or additionally, as shown in FIG. 7, a light guide 18 may be roughened or otherwise microstructured as appropriate in a region 18 awhere light leakage is to be prevented or suppressed. This copolymerization, in particular roughening, causes diffuse reflection of the light into the light guide 18, and indeed frequently at an angle which causes enhanced light emission from the light guide 18 at the location of the light guide 18 illuminated by the back reflection. Consequently, light is radiated from an unembounsed (smooth) region 18 bof the light guide 18 in an amplified manner. Roughening may be effected, for example, by sandblasting or etching, and makes the roughened surface region appear milky or diffuse.In order to reduce light losses, an upper, free cover surface of the light guides is likewise configured to be more opaque.The light guide 18 is masked (designed or prepared) for a light emission of the same type over its length, preferably at a circumferential angle α about its longitudinal axis L which is constant over its length, for a targeted light emission. The circumferential angle α is preferably between about 45° and about 270°, so that in a development, more light can emerge in the circumferential angle region complementary thereto between about 315° and about 90° (at which the surface of the light guide 18 is in particular smooth and uncoated).Alternatively, the light guide may have a plurality of regions 18 a, which are spaced apart along its length and are arranged, for example, in series. As a result, a light intensity or a light flux can be varied over the length and concentrated, for example, on specific height ranges, for example, on regions between slide-in supports of an oven.FIG. 8 shows a light guide 18 on which an intermediate piece adjoins at an angle at the bending angle β. Thus, the lighting device 16 can extend substantially over the entire height of the oven door 1. The bending angle β is here between 90° and 180°. Alternatively, the light guide may be angled at the bending angle β.For a further increase in the photometric illumination efficiency or light yield, a reflector 28 can be provided on the light guides 18, in each case, which reflector partially surrounds the light guide 18, in particular via its longitudinal section radiating into the furnace chamber 12 (here: the section projecting into the heat region W). Thus, FIG. 9 shows a tubular or tubular reflector 28 having a circular sector-shaped configuration in profile. The reflector 28 partially surrounds the light guide 18 (serving as a light-emitting element) with respect to a circumferential direction. The reflector 28 surrounds the light guide 18 in a longitudinal section outside the cold chamber K or inside the warm chamber W.A light transmission opening 29 forming in a lateral surface 28 aof the reflector 28 has an opening angle γ with respect 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 complementary circumferential angle (1-α), with α=27° here of the light guide 18, corresponds to the opening angle γ of the light outlet opening 29, wherein, in addition, the surface region 18 aof the light guide 18, which prevents or suppresses the light emission, is directed onto the reflector 28. The reinforced light-emitting region 18 bof the light guide 18 is directed analogously to the light outlet opening 29. Thus, a high proportion of the light emitted by the light guide 18 is emitted directly from the light outlet 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 consequently be radiated directly through the light passage 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 furnace chamber. This can be advantageous in particular for door profiles 2 made of plastic.The reflector 28 can be formed to be specular on its side facing the light guide 18 or, preferably for uniform light emission, diffusely reflective.The reflector 28 may simultaneously serve as a support for the light guide 18.The reflector 28 can be provided in one part or in multiple parts. In a multi-part construction, different parts can be provided for different functions, e.g. for reflecting, supporting, positioning etc., which supports a standardization of components.For lower temperatures, the reflector 28 can be, for example, a reflectively coated plastic body. For higher temperatures, the reflector 28 can be, for example, a metal body with reflective coating or a metal body with glossy polishing. A reflective coating can comprise, for example, aluminum and / or chromium. For example, the reflector 28 may be an iron or steel sheet coated with high-gloss aluminum.FIG. 10 shows a further possible embodiment of the illumination device 16 with a reflector 28. The light-emitting diodes 17 are directed into the reflector 28 and thus substantially only irradiate the reflector 28. The light-emitting diodes 17 are suspended on thin cross struts 31, via which they can also be supplied with current.In order to thermally protect the light emitting diodes 17 from thermal radiation which is urgent from the furnace chamber 12, heat shields 32 which function as heat-reflecting screens are fastened to the cross struts 31 at the rear of the light emitting diodes 17.The reflector 28 is designed here to be diffusely reflecting for uniform light emission.Of course, the present invention is not limited to the illustrated embodiment.Thus, the light guide and / or the reflector can also be curved or angled with respect to their length, i.e. not just configured to be straight.List of reference characters1 Oven door 2 door profile 3 frame 4 front pane 5 holder 6 intermediate pane 7 intermediate pane 8 inner pane 9 attachment 10 door handle 11 charging opening 12 oven chamber 13 oven 13 a housing 14 partition 15 guide 16 lighting device 17 light source, light-emitting diode 18 light guide 18 a roughened region 18 b smooth region 19 carrier 20 intermediate piece 21 top surface 22 cross piece 23 light transmission openings 24 thermal insulation 25 flange 26 lateral surface of the light guide 27 muffle 28 reflector 28 a lateral surface of the reflector 29 light transmission opening 30 door edge 31 cross strut 32 thermal shield A cutout K cold region L longitudinal axis M light emission pattern W warm region α circumferential angle region β bending angle γ opening angle

Claims

Domestic appliance door (1) in the form of a furnace door for closing a charging opening (11) of a receiving space (12) of a domestic appliance (13) in the form of a furnace, wherein - the domestic 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 vertically upright reflector (28), which is formed in the shape of a tube with at least one light outlet opening (29) formed in a lateral surface (28a), which light outlet opening is directed into the receiving space (12) and extends over the entire length of the lateral surface (28a), characterised in that - the domestic 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 an 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 a pane (5-7) adjacent thereto, - the reflectors (28) extend at least over a height of the charging opening (11), and - the reflectors (28) thermally shield a respectively adjacent, laterally arranged door profile (2).Domestic appliance door (1) according to claim 1, characterised in that the door profiles (2) consist of plastic.Domestic appliance door (1) according to one of the preceding claims, characterised 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.Domestic appliance door (1) according to one of the preceding claims, characterised in that the at least one light-emitting element (17, 18) illuminating the reflector (28) has at least one light guide (18).Domestic appliance door (1) according to claim 4, characterised in that the light guide (18) has at least one surface region (18a) at which light emission 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 emission is directed towards the reflector (28).Domestic appliance door (1) according to claim 1, characterised 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).Domestic appliance door (1) according to claim 6, characterised in that the at least one light source (17) has a heat shield (32) on a side facing away from the reflector (28).Domestic appliance door (1) according to one of the preceding claims, characterised in that the light outlet opening (29) has a circumferential angle γ between approximately 90° and approximately 270°.Domestic appliance door (1) according to one of the preceding claims, characterised in that the reflector (28) represents a holder for at least one further element of the lighting device (16).Domestic appliance door (1) according to one of the preceding claims, characterised in that at least one reflector (28) extends parallel to a lateral door profile (2) at a distance of up to 150 mm.Domestic appliance door (1) according to one of the preceding claims, characterised 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.Domestic appliance door (1) according to claim 11, characterised in that the light guide (18) consists of a vitreous material.Domestic appliance (13) in the form of a furnace with a domestic appliance door (1) in the form of a furnace door, characterised in that the domestic appliance door (1) is a domestic appliance door (1) according to one of the preceding claims.Domestic appliance (13) according to claim 13, characterised in that the domestic appliance (13) is a pyrolyzing capable domestic appliance (13).

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