Household appliance door with lighting fixture
Patent Information
- Application Number
- DE102011080072
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2011-07-29
- Publication Date
- 2025-02-20
- Estimated Expiration
- 2031-07-29
Smart Images

Figure 00000000_0000_ABST
Abstract
Description
[0001] The invention relates to a household appliance 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 pyrolysis-capable household appliance having such a household appliance door.
[0002] EP 1 995 522 B1 discloses an oven within the oven door of which lighting means are provided for illuminating a furnace muffle that can be closed by the oven door. These lighting means have a plurality of light sources which radiate their light in a directly focused manner towards the furnace muffle. The light sources can be LEDs arranged in series, each directing their light towards the furnace muffle. For this purpose, it is shown that the LEDs are fastened to a sheet metal support in a left and right area of the oven door, with alignment of the LEDs being achieved by appropriate local alignment of the sheet metal support. The oven door can be cooled by natural ventilation. However, the oven door has a comparatively complex construction. The LEDs are also inadequately protected against high temperatures, such as those that occur during pyrolysis operation.
[0003] Furthermore, document US 2009 / 0 316 385 A1 discloses 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 for connecting the LED assembly to an external voltage source. The LED assembly consists of an LED mounted on a circuit board containing additional circuitry for powering the LED and a heat sink for dissipating heat from the LED. The mounting bracket can be attached to an oven door to support the LED assembly 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 chamber. By positioning the light assembly outside the oven chamber and adjacent to the sidelight window, the LED can be operated within the required temperature limits.
[0004] Furthermore, the document DE 10 2005 045 367 A1 discloses an interior lighting device for a cooking appliance with a lighting unit for radiating illumination light into the interior of the cooking appliance. To provide an interior lighting device for a cooking appliance that is particularly cost-effective to manufacture and can also be operated in an energy-saving manner using a safe, low-voltage power supply, it is proposed that the lighting unit comprise at least one light-emitting diode.
[0005] In addition, the document DE 10 2007 015 237 A1 discloses a household appliance device, a cooking appliance device, with a door unit for closing a usable space and with a lighting unit which is provided for illuminating the usable space at least when the usable space is closed, wherein the lighting unit has at least one light source unit which is arranged in the door unit. 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.
[0006] This object is achieved according to the features of the independent claims. Preferred embodiments can be found in particular in the dependent claims.
[0007] The problem is solved by a household appliance door for closing a loading opening of a receiving space of a pyrolysis-capable 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 lighting device has at least one light guide, into which light from at least one light source can be coupled and which is arranged and configured to transmit 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 wide-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, e.g. if made of glass or glass ceramic.
[0008] Indirect light can be reflected into the recording room. In a further development, a fiber optic cable can radiate light into the recording room both directly and indirectly.
[0009] According to the invention, the at least one light guide 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. Furthermore, the presence of at least one intermediate pane enables good thermal shielding of the front pane, since the at least one intermediate pane can then be made thick without affecting the lighting. According to the invention, at least one light guide extends at least over the height of the loading opening. This allows the receiving space to be illuminated across its entire height, even when at least one shelf level or similar is occupied. The light guide is preferably oriented vertically.
[0010] According to the invention, at least one light guide thermally shields an adjacent door profile, at least in part. The light guide can therefore be arranged, in particular, between the receiving space and the door profile. This can reduce heating of the door profile, which is particularly advantageous for plastic door profiles. Such a light guide can, in particular, be a vertical light guide, which can, in particular, extend over the height of the loading opening.
[0011] One design is for the light guide to be made of a vitreous material (glass, glass-ceramic, or similar). The glass is preferably borosilicate glass. Vitreous material is highly temperature-resistant and typically transparent. Optical properties can be easily and precisely modified by adding fillers. For example, the light guide can be designed as a diffusely scattering light guide. Furthermore, vitreous material is comparatively inexpensive, versatile in its formability, and its surface is easily post-treated.
[0012] Alternatively, the light guide can be made of plastic, which further simplifies manufacturing. The plastic is preferably a highly temperature-resistant plastic.
[0013] The plastic is preferably made of polycarbonate (PC), acrylonitrile butadiene styrene (ABS) and / or polymethyl methacrylate (PMMA).
[0014] 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.
[0015] In principle, one, two, or more light guides can be provided. At least one light guide can be configured and arranged to illuminate several (in particular all) insertion levels of the receiving space, in particular a vertical light guide.
[0016] A light guide can be arranged vertically or horizontally. A vertical arrangement enables illumination across the height of the receiving space, in particular across multiple drawer levels. A vertical light guide preferably runs parallel to a door profile of the household appliance door. To provide the largest possible viewing area, at least one vertically arranged light guide can be arranged, in particular, in an area of a left edge (light guide arranged on the left side) and / or a right edge (light guide arranged on the right side) of a viewing window of the household appliance door.
[0017] In particular, two light guides may be provided to illuminate a shelf level. The use of two light guides can reduce shadow formation in the receiving space. A light guide arranged on the left side and a light guide arranged on the right side can be designed and / or arranged, in particular, mirror-symmetrically to a door center axis to support uniform illumination of the receiving space.
[0018] Alternatively, at least one light guide may be configured and arranged to illuminate only one shelf level at a time. For this purpose, the light guide may 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 light guide may 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.
[0019] In a further development, the thickness of at least one light guide is preferably between 5 mm and 30 mm. However, the thickness is not limited to this.
[0020] Another refinement is 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 broad light emission, a curved or 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 to this; it can also be, for example, angular and / or free-form.
[0021] The light guide is preferably straight, but can also be curved.
[0022] In a further embodiment, the light guide has at least one surface region where light emission is prevented or suppressed, and at least one (particularly complementary) surface region intended for light emission, wherein the at least one surface region intended for light emission is directed substantially into the receiving space. This facilitates targeted illumination of the receiving space in a compact manner.
[0023] It is a special embodiment that the at least one surface area preventing or suppressing light emission is masked, in particular coated or roughened to be opaque. For example, a light guide can be coated to be light-absorbing or, for high light output, preferably reflective, where light emission is to be prevented. Roughening or other microstructuring can be effected, for example, by sandblasting or etching and makes the roughened surface area appear milky or diffuse. The roughening or other microstructuring causes diffuse back-radiation or back-reflection of the light into the light guide, frequently 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 particularly increased from an uncoated or roughened (ie, smooth) area of the light guide.
[0024] An advantageous development for uniform light emission along its length is that the light guide is designed or prepared at a circumferential angle α that is constant along 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 vary with the length of the light guide.
[0025] The circumferential angle α preferably lies in a range between approximately 45° and approximately 270°, so that, in a further development, increased light can emerge in the complementary circumferential angle range 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 spaced-apart regions along its length, which, for example, have a circumferential angle α that is identical to one another. The regions can be arranged in a row or, for example, at an angular offset around the longitudinal axis.
[0026] In a further embodiment, an intermediate piece is arranged 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 luminous efficacy.
[0027] Another embodiment is for the intermediate piece to be or include an optical element. This allows for particularly versatile beam guidance, especially for high light output.
[0028] In a further embodiment, 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 illumination efficiency. For this purpose, the length of the respective light guide is, in particular, less than the height of the oven door.
[0029] It is also an embodiment that the intermediate piece is made of plastic and the light guide is made of glass.
[0030] In another embodiment, at least one light guide projects into a cold zone of the household appliance door, and the at least one light source (associated, i.e. radiating light into this light guide directly or indirectly, e.g. via an intermediate piece) is also located in the cold zone. The cold zone is intended to be arranged to the side of the loading opening when the household appliance door is closed. A cold zone can therefore be understood to mean, in particular, a zone 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 zone, it can be kept at a low thermal level even at high temperatures in the accommodation space. In particular, the light source is not exposed to direct thermal radiation.Consequently, a particularly long service life of the lighting device can be achieved, even if an associated household appliance is capable of pyrolysis.
[0031] The intermediate piece is also preferably located in the cold area, especially in pyrolysis-capable household appliances. A particularly suitable embodiment is for the intermediate piece to be made of plastic and the light guide to be made of glass. This provides cost-effective and versatile light coupling and 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.), particularly as a single piece. This simplifies manufacturing.
[0032] In general, the cold zone can be, in particular, the cold zone located on the side of the appliance door on which it is pivotable or has at least one door hinge. Such a cold zone is comparatively large, so that sufficient, uncrowded space is available for accommodating the at least one light source.
[0033] One embodiment provides a lower cold zone. A lower cold zone can be understood, in particular, as a cold zone located below the loading opening when the appliance door is closed. Such a cold zone is particularly available for downward-opening doors such as oven doors.
[0034] Alternatively, the cold area can be a lateral cold area, particularly in the case of a household appliance door that opens or pivots sideways (e.g. for refrigerators or microwave ovens) or, particularly in the case of a household appliance door that opens upwards or pivots at the top (e.g. in the case of a high-mounted appliance).
[0035] It is another embodiment that the cold area is separated from a warm area covering the loading opening in a closed state of the household appliance door by means of a partition and that the partition has at least one light transmission opening for transmitting light generated by means of the at least one light source and that at least one light guide extends through a light transmission opening.
[0036] Another feature is that at least the cold area can be forced ventilated.
[0037] Another embodiment provides that at least one light guide extends parallel to a side door profile at a distance of up to 150 mm. A further development provides that the at least one light source is arranged in a sub-region 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.
[0038] In yet another embodiment, the at least one light source comprises at least one semiconductor light source. A semiconductor light source is particularly durable, structurally compact, and can generate a high luminous flux.
[0039] Preferably, the at least one semiconductor light source comprises at least one light-emitting diode. If multiple light-emitting diodes are present, they can illuminate in the same color or in different colors. A color can be monochrome (e.g., red, green, blue, etc.) or multichrome (e.g., white). Multiple light-emitting diodes can generate 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 packaged light-emitting diode or in the form of at least one LED chip. Multiple 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 shared optics for beam guidance, e.g.,at least one Fresnel lens, collimator, etc. Instead of or in addition to inorganic light-emitting diodes, e.g., based on InGaN or AlInGaP, organic LEDs (OLEDs, e.g., polymer OLEDs) can also generally be used. Alternatively, the at least one semiconductor light source can comprise, for example, at least one diode laser.
[0040] The appliance door can have at least one electrical connection to the associated (remaining) appliance to supply power to the at least one light source. When using at least one LED, a corresponding driver can be located in the appliance door, particularly in the cold area, or alternatively in the (remaining) appliance.
[0041] Another feature is that the appliance door is capable of forced ventilation. This further reduces the temperature inside the appliance door, extending the service life of its components and improving user safety from high temperatures. A further development is that at least the cold area is capable of forced ventilation. This allows the light sources that generate waste heat to be cooled particularly effectively.
[0042] Another embodiment provides for the at least one light source to be thermally conductively connected to at least one heat sink. This improves heat dissipation and cooling of the light source, thus extending its service life. The heat sink can simultaneously serve as a holder for the LED 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 cost-effective production, reduced assembly tolerances, and easy installation.
[0043] Another embodiment provides that the cold zone is separated from a warm zone, which covers the loading opening when the household appliance door is closed, by means of a partition, and that the partition has at least one light transmission opening for transmitting light generated by the at least one light source. This facilitates light guidance between the cold zone and the warm zone. The partition can be at least partially permeable to air to allow a cooling air flow between the panes of the household appliance door. Another embodiment provides that at least one light guide extends through a light transmission opening. This allows elements upstream of the light guide to be accommodated in the cold zone, where they are thermally protected.
[0044] In yet another embodiment, at least one light guide is assigned a reflector to reflect light incident from this light guide into the recording space. This increases the light output.
[0045] The reflector can, for example, be specular or diffusely reflective.
[0046] The reflector can also be tubular with a hollow cylindrical profile, which has at least one light exit opening in its outer surface. The reflector can then accommodate, in particular, the light guide.
[0047] The hollow cylindrical profile can be circular cylindrical and / or square.
[0048] The at least one light exit opening may comprise a light exit opening extending over the entire length of the lateral surface.
[0049] The at least one light exit opening can in particular be directed into the receiving space.
[0050] The reflector can in particular serve as a heat shield, in particular to thermally shield a door profile from the receiving space.
[0051] The reflector may further serve as a holder for at least one or more elements of the lighting device.
[0052] It is another embodiment that a cross-sectional profile of at least one optical fiber is ovally curved at least in sections, wherein a more strongly curved region of a lateral surface of the optical fiber faces the receiving space.
[0053] Furthermore, one embodiment provides 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 receiving space can also be referred to as an oven chamber or (in the case of an oven) as an oven pipe. Pyrolysis can be performed, particularly in an oven, and effective lighting is required due to the comparatively large receiving space (oven chamber).
[0054] The problem is also solved by a pyrolysis-capable household appliance with at least one household appliance door as described above.
[0055] The household appliance offers the same advantages as the household appliance door and can also be designed in a similar way.
[0056] The household appliance may, in particular, fall into the category of "white goods" and be used, in particular, for performing household chores such as cooking, baking, washing, cleaning, etc. The household appliance may 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).
[0057] The household appliance can, in particular, be a kitchen appliance. It is particularly preferred that the household appliance be a cooking appliance (e.g., comprising an oven and / or a steamer), in particular an oven.
[0058] The invention is described in more detail schematically in the following figures using exemplary embodiments. For clarity, identical or equivalent elements may be provided with identical reference numerals. Fig. 1 shows an exploded view of an oven door in a diagonal rear view; Fig. 2 shows a view from the rear of the oven door with the rear pane removed; Fig. 3 shows the oven door Fig. 2 in a rear view; Fig. 4 shows a section of Fig. 2 in the area of a light source; Fig. 5 shows a section of Fig. 3 in the area of the light source; Fig. 6 shows an oven equipped with the oven door as a sectional view in plan view with an associated light emission pattern; Fig. 7 shows an oblique view of another possible light guide of the oven door; Fig. 8 shows a side view of another possible light guide for the oven door and; Fig. Figure 9 shows a sectional view in plan view of a possible light guide of the oven door with a reflector.
[0059] Fig. 1 shows an exploded view of a basic structure of a household appliance door in the form of an oven door 1, viewed diagonally from the rear. The oven door 1 has two laterally arranged door profiles 2, which are connected to one another by a rectangular frame 3.
[0060] A front pane 4 is attached to the front of the door profiles 2. For this purpose, the front pane can have a plurality of brackets 5 glued to the front pane 4, which can engage with the door profiles 2. At least one intermediate pane can optionally be inserted between the door profiles 2, here two intermediate panes 6, 7, for example. The rear of the oven door 1 can be covered by an inner pane 8, which can also be fastened to the door profiles 2, for example, by means of brackets 5 glued to it. The oven door 1 is covered on the top across its entire width by an attachment 9, which has a door handle 10.
[0061] 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 chamber 12 of an oven 13 that can be closed by the oven door 1 (see in more detail Fig. 6) directly covers the area of the window. The intermediate panes 6, 7 are limited to this warm area W for thermal insulation.
[0062] Below the warm zone W is a lower cold zone K, which is designed to be located to the side, here below, the loading opening 11 when the oven door 1 is closed. The cold zone K is forced ventilated by a fan (not shown), so that a stream of cooling air flows through it when the fan is switched on. Forced ventilation can be achieved by a fan located in the oven door 1 (not shown) or a fan located in a body of the oven 13.
[0063] 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.
[0064] 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.
[0065] Fig. 2 shows an oblique view of the back of the oven door 1 with the rear pane removed in greater detail. Fig. 3 shows the oven door 1 with the rear inner pane 8 removed in a rear view.
[0066] 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 Fig. 6). The lighting device 16 has a light source in the form of a light-emitting diode 17 on the left and right sides, each of which is connected to a rod-shaped light guide 18. The left-side part and the right-side part can, in particular, be designed to have an analogous shape (e.g., mirror-symmetrical to a door center line).
[0067] The LEDs 17 are located in the cold zone K, so they are sufficiently thermally protected even at high temperatures in the furnace chamber 12. Firstly, the LEDs 17 are not directly exposed to the heat radiation escaping from the furnace chamber 12 and are also ventilated by the forced ventilation of the cold zone K. This allows the LEDs 17 to withstand temperatures of 400°C to 500°C in the furnace chamber 12 during pyrolysis operation without a significant reduction in their service life.
[0068] The light-emitting diodes 17 are arranged here on the left and right sides 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.
[0069] As also partially enlarged in Fig. 4 and Fig. As shown in Figure 5, the light-emitting diodes 17 are mounted on respective supports 19, which in turn are glued to the windshield 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 flow flowing in the cold region K. The supports 19 can also provide a power connection for the light-emitting diode(s) 17.
[0070] For improved heat dissipation, the supports 19 can have at least one cooling structure (not shown) on their outer side, e.g. cooling fins, cooling pins, cooling fins, etc. The cooling structure can be connected integrally to the support 19 or, e.g., as a dedicated heat sink, can be firmly connected to the support 19, e.g., screwed or clamped thereto or glued thereto.
[0071] Alternatively or additionally, heat dissipation from the LEDs 17 may be achieved by a thermally well-conducting connection to the door profiles 2, e.g. by connecting the supports 19 to a respective door profile 2.
[0072] 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).
[0073] An intermediate piece 20 is arranged above each of the LEDs 17 and thus optically connected downstream. The intermediate piece 20 serves to couple in the light emitted by the associated LED 17 and to decouple it again in a targeted manner. For this purpose, the intermediate piece 20 has a truncated cone-shaped basic shape and, on a smaller lower cover surface facing the LED 17, has a dome-like, e.g., spherical cap-shaped recess (not shown), which at least substantially arches over the LED 17, including laterally. The intermediate piece 20 thus also serves as an optic or an optical element, in this case: for beam shaping.
[0074] Since the intermediate piece 20 is located entirely within the cold zone 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, for example, glass, glass ceramic, etc. The intermediate piece 20 is also mounted on the carrier 19.
[0075] The light guide 18 is flatly connected to an upper, flat cover surface 21 of the intermediate piece 20, facing 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 sufficiently match, particularly 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.
[0076] 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 LED 17 of each side are arranged in series or collinearly, enabling a high photometric illumination efficiency. For this purpose, the length of each light guide 18 is less than the height of the oven door 1. The length of the light guides 18 is the same.
[0077] In order to guide the light guides 18 through the partition 14, the partition has two light-transmitting 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.
[0078] 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 be made of a thermally resistant material that can withstand temperatures of, for example, 400°C to 500°C occurring in the receiving chamber, particularly during pyrolysis, without damage. This material is preferably glass or glass ceramic.
[0079] The light guide 18 and the intermediate piece 20 can be formed as a single piece, e.g., from glass, for easier assembly. A light guide 18 then has, in particular, a section that corresponds to the intermediate piece 20 in terms of design and / or function, but is integrated into the light guide 18. Alternatively, 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.
[0080] The light guides 18 are arranged and configured to radiate light coupled into them through the loading opening 11 into the furnace chamber 12. Fig. 6 shows a plan 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 highly uniformly. 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 when 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 thus shield the adjacent door profile 2 from heat from the oven chamber 12. This can be particularly advantageous for door profiles 2 made of plastic.
[0081] To form the furnace chamber 12, the baking oven 13 has a muffle 27 open on one side through the loading opening 11. The muffle 27 is separated from a housing 13a of the baking oven 13 by a thermal insulation 24. In its closed state shown, the baking oven door 1 rests laterally on a flange 25 of the muffle 27 that circumferentially surrounds the loading opening.
[0082] 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 irradiation into 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.
[0083] The thickness of the circular-cylindrical light guides 18 is preferably between 5 mm and 30 mm, but is not limited thereto. A cross-sectional profile of the light guides 18 is curved at least in sections and can be, for example, circular-cylindrical, circular-segment-shaped, or oval. 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.
[0084] For 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 certain areas, particularly 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 coated with a light-absorbing or, preferably for high light output, a reflective coating.
[0085] Alternatively or additionally, as in Fig. 7, 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, frequently 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, more light is emitted 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 cover surface of the light guide is also designed to be rather opaque.
[0086] The light guide 18 is designed or prepared for targeted light emission, preferably at a circumferential angle α that is constant along its length, around its longitudinal axis L. The circumferential angle α is preferably between approximately 45° and approximately 270°, so that, in a further development, increased light can emerge 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).
[0087] Alternatively, the light guide may have several regions 18a spaced apart along its length, arranged, for example, in series. This allows the light intensity or luminous flux to be varied along its length and concentrated, for example, on specific height ranges, such as between the shelf supports of an oven.
[0088] Fig. Figure 8 shows a light guide 18, to which an intermediate piece is attached at an angle β. Thus, the lighting device 16 can extend essentially over the entire height of the oven door 1. The angle β here is between 90° and 180°. Alternatively, the light guide may be angled at an angle β.
[0089] For a further increase in the photometric illumination efficiency or luminous efficacy, a reflector can be provided on each of the light guides 18, which reflector partially surrounds the light guide 18, in particular over its longitudinal section radiating into the furnace chamber 12 (here: the section projecting into the heat area W).
[0090] This shows Fig.9 shows a tubular or tubular reflector 28 with a circular sector-shaped profile. The reflector 28 partially surrounds the light guide 18 (serving as a light-emitting element) in a circumferential direction. The reflector 28 surrounds the light guide 18 in a longitudinal section outside the cold space K or inside the warm space W.
[0091] A light transmission opening 29 formed in a lateral surface 28a of the reflector 28 has an opening angle γ with respect to a longitudinal axis L of the light guide 18, here γ = 90°. The light transmission opening 29 points toward the furnace chamber 12. The orientation and size of the opening 29 allow the furnace chamber 12 to be specifically illuminated.
[0092] The complementary circumferential angle (1-α), with α = 270° here, of the light guide 18 corresponds to the aperture angle γ of the light exit opening 29, with the surface area 18a of the light guide 18 preventing or suppressing light exit being directed toward the reflector 28. The area 18b of the light guide 18 emitting more light is similarly directed toward the light exit opening 29. Thus, a high proportion of the light emitted by the light guide 18 is emitted directly from the light exit opening 29.
[0093] The reflector 28 and the light guide are aligned parallel to each other 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.
[0094] As a further advantage, in addition to the light guide 18, the reflector 28 can also serve as a heat shield, thermally shielding the door profile 2 from the furnace chamber. This can be particularly advantageous for door profiles 2 made of plastic.
[0095] The reflector 28 can be specular on its side facing the light guide 18 or, preferably for uniform light emission, diffusely reflecting.
[0096] The reflector 28 can simultaneously serve as a carrier for the light guide 18.
[0097] The reflector 28 can be a single-piece or multi-piece design. In a multi-piece design, different parts can be provided for different functions, e.g., for reflecting, supporting, positioning, etc., which supports component standardization.
[0098] 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 metal body with a reflective coating or a glossy polished metal body. A reflective coating can be made of aluminum and / or chrome, for example. For example, the reflector 28 can be an iron or steel sheet coated with a high-gloss aluminum finish.
[0099] Of course, the present invention is not limited to the embodiment shown.
[0100] The light guides can also be curved or angled in terms of their length, i.e. not just straight.
[0101] In a further development, the reflector can serve as a carrier for the light guide, the intermediate piece, and the LED(s). This allows a prefabricated lighting unit to be manufactured and assembled particularly easily and, if necessary, in a standardized manner. Manufacturing tolerances can also be reduced.
[0102] There may also be only one light guide or more than two light guides. List of reference symbols 1 oven door 2 door profile 3 frames 4 Windscreen 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 guides 18a roughened area 18b smooth area 19 carriers 20 intermediate piece 21 Cover 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 A section K Cold area L Longitudinal axis M light emission pattern W Warm area α circumferential angle range β bending angle γ opening angle
Claims
[1] Household appliance door (1) for closing a loading opening (11) of a receiving space (12) of a household appliance (13), wherein - the household appliance door (1) has at least one lighting device (16) with at least one light source (17), in particular light-emitting diode (17), for illuminating the receiving space (12), - the lighting device (16) has at least one light guide (18) into which light from at least one light source (17) can be coupled and which is arranged and configured to transmit the light coupled into it and to radiate it into the receiving space (12), characterized by , that - the household appliance door (1) is designed to close a loading opening (11) of a receiving space (12) of a pyrolysis-capable household appliance (13) and that at least one light guide (18) - is arranged between an inner pane (8) and an adjacent pane (7) which is fastened to side door profiles (2), - extends at least over a height of the loading opening (11) and - thermally shields the adjacent door profile (2). [2] Household appliance door (1) according to claim 1, characterized by that the light guide (18) consists of a glass-like material or of plastic. [3] Household appliance door (1) according to one of the preceding claims, characterized by 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 (18b) provided for light emission is directed into the receiving space (12). [4] Household appliance door (1) according to claim 3, characterized bythat the at least one surface area (18a) preventing or suppressing light emission is masked, in particular coated or roughened to be opaque. [5] Household appliance door (1) according to one of the preceding claims, characterized by that at least one optical fiber (18) is preceded by an intermediate piece (20), into which intermediate piece light from at least one light source (17) can be coupled and which transmits the coupled light to the optical fiber (18), wherein at least one optical fiber (18), the associated intermediate piece (20) and the at least one light source (17) radiating light into the intermediate piece (20) are arranged collinearly. [6] Household appliance door (1) according to claims 2 and 5, characterized by that the intermediate piece (20) is made of plastic and the light guide (18) is made of glass. [7] Household appliance door (1) according to one of the preceding claims, characterized bythat at least one light guide (18) projects into a cold area (K) of the household appliance door (1) and the at least one light source (17) is also located in the cold area (K). [8] Household appliance door (1) according to claim 7, characterized by in that the cold area (K) is separated from a warm area (W) covering the loading opening (11) when the household appliance door (1) is closed by means of a partition (14), and the partition (14) has at least one light transmission opening (23) for transmitting light generated by the at least one light source (17), and at least one light guide (18) extends through the light transmission opening (23). [9] Household appliance door (1) according to one of claims 7 to 8, characterized by that at least the cold area (K) can be forced ventilated. [10] Household appliance door (1) according to one of the preceding claims, characterized bythat at least one light guide (18) is rod-shaped and has a diameter between 5 mm and 30 mm. [11] Household appliance door (1) according to one of the preceding claims, characterized by that at least one light guide (18) extends parallel to a lateral door profile (2) at a distance of up to 150 mm. [12] Household appliance door (1) according to one of the preceding claims, characterized by that at least one light guide (18) is assigned a tubular reflector (28) with at least one light exit opening (29) on the jacket side, wherein the light exit opening (29) is directed into the receiving space (12). [13] Household appliance door (1) according to one of the preceding claims, characterized by that a cross-sectional profile of at least one optical fiber (18) is ovally curved at least in sections, wherein a more strongly curved region of a lateral surface of the optical fiber (18) faces the receiving space (12). [14] Household appliance door (1) according to one of the preceding claims, characterized by that the household appliance door (1) is a cooking appliance door, in particular an oven door. [15] Pyrolysis-capable household appliance (13) with a household appliance door, characterized by that the household appliance door is a household appliance door (1) according to one of the preceding claims.
Citation Information
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