Heating device for panes

Abstract

The invention relates to a heating device (10) for panes (20), wherein at least two bus bars (30) are the positive poles and at least one bus bar is the negative pole and the bus bars are interconnected by means of heating conductors (50), thereby forming at least two heating circuits (22). According to the invention, these heating circuits are each protected by an electronic fuse (60).

Description

[0001] Description

[0002] Heating device for windows

[0003] The invention relates to a heating device for windows, in which at least two busbars are designed as positive poles and at least one busbar is designed as negative pole and are connected by heating conductors. This creates at least two heating circuits, each of which is protected by an electronic fuse.

[0004] The power requirement for heating windows increases proportionally with their size. Typically, a heating circuit is formed with two busbars, forming a positive and a negative pole, and heating conductors running between them. In the current state of the art, these are usually equipped with fuses to protect the heating circuit.

[0005] Electronic fuses have since become popular for protecting electrical circuits. These elements, also known as "digital fuses," have a more limited current carrying capacity. If the power consumption of a device exceeds this limit, the current must be divided among several subcircuits, each of which has a power consumption below the limit of its assigned electronic fuse. This, in turn, necessitates a larger number of contacts, which leads to increased costs and increased production effort, since each subcircuit must be connected individually to the power supply.

[0006] Therefore, the object of the invention is to propose a solution with which the heating of large areas or panes can be realized using electronic fuses while at the same time being cost-effective.

[0007] The object of the invention is achieved with a heating device according to claim 1, a method for its production according to claim 9 and a vehicle according to claim 10. Further preferred embodiments of the invention emerge from the remaining features mentioned in the subclaims. A heating device for windows according to the invention is formed with at least two first busbars as positive poles and at least one second busbar as negative pole, wherein the at least two first busbars of the positive poles are connected to the at least one second busbar of the negative pole by heating conductors, so that at least two heating circuits are formed, and it is characterized in that each of the heating circuits formed in this way is protected by a respective electronic fuse.

[0008] The heating device is thus designed such that at least two first busbars are provided for providing the positive poles and at least one second busbar for providing a negative pole. The first busbars are each connected to the second busbar(s) of the negative pole by means of heating conductors. The heating conductors thus each extend from the at least two first busbars of the positive poles and terminate in the at least one busbar of the negative pole.

[0009] At least two heating circuits are formed, each consisting of a first busbar of the positive pole and the area of ​​the at least one busbar of the negative pole, into which the heating conductors of the associated first busbar open. It is particularly advantageous if the number of second busbars at the negative pole is at least one (number "1") less than the number of first busbars in order to reduce the number of necessary contacts with a power supply. If one busbar of the positive pole were connected to one of the negative pole, as in the prior art, two connections would result in such a heating circuit. If two heating circuits are formed in this way, four contacts would result.If, however, the heating conductors are routed from several first busbars of the positive poles to at least one second busbar of the negative pole and connected to this, each of the first busbars of the positive poles requires a contact, but at least one contact can be omitted on the negative pole side, thereby reducing costs and assembly effort. The more first busbars are connected to a common second busbar, the greater the savings potential. However, a corresponding number of first and second busbars is still within the scope of the invention.

[0010] According to the invention, each of the heating circuits now formed between a first busbar and the at least one second busbar is protected by an electronic fuse. Electronic fuses, also colloquially known as digital fuses, are a form of overcurrent protection device that has an extremely compact design and trips or switches much more quickly than conventional circuit breakers such as thermomagnetic circuit breakers or super-fast-acting fuses. They also have no mechanical parts, which provides greater protection against failures. The fuses are then selected to match the power requirements of the individual heating circuits formed and / or the heating circuits are formed by a suitable number of first and second busbars so that they do not exceed the load capacity of the electronic fuses.In this way, the heating circuits can be divided and protected according to requirements, so that an optimization can be achieved in terms of heating output, costs and necessary installation space.

[0011] With the heating device according to the invention, it is now possible to heat even large windows, such as the increasingly large rear windows of vehicles, using digital fuses. Depending on the design of the heating circuits, the number of necessary contacts and connections can be reduced. This also speeds up and simplifies the production and assembly of such windows.

[0012] A particularly preferred embodiment of the heating device according to the invention is that it is designed with exactly one busbar as the negative pole and exactly two busbars as the positive poles. This embodiment is particularly suitable for heating devices in vehicles, in particular their rear windows. In this case, two first busbars can form the positive poles and a second busbar the negative pole, which is connected to the pulse poles by means of heating conductors. The two first busbars in this configuration can also be referred to as half-bars if they are identical in terms of size and transferable power. By splitting the heating circuits into two, only three contacts and thus only three connections to the power supply are necessary: ​​one each at the pulse poles and one at the negative pole, instead of four if the second busbar of the negative pole were also split.Such savings can have significant effects, especially in the production of mass-produced items or mass-produced products.

[0013] It is also advantageous if the at least two heating circuits are of identical design. This means that the elements, and in particular the first busbars and / or the second busbars, are identical in size and transmittable power. This simplifies and accelerates production, as different types, sizes, and designs of busbars do not have to be manufactured and tested. Busbars in heating devices of the type described above are usually printed, so that only one print pattern can be used for all similar busbars.

[0014] However, there are applications where a similar design of at least two heating circuits is not practical or desirable, for example, because there are areas with different heating requirements. In these cases, it may be appropriate to create heating surfaces with a defined shape and / or different heating effects using at least two heating circuits.

[0015] A defined shape refers to any other shape that creates a difference in shape and / or size between the at least two heating circuits. This allows, for example, the shape of the pane of glass and an object protected by it to be followed. However, specific geometric shapes and patterns can also be designed, which are formed by the heating circuits using the busbars and heating conductors, creating decorative effects that become visible when the heating device is in use. The shape can also accommodate different heating requirements and, in particular, be combined with different heating outputs.

[0016] The design of different heating surfaces can accommodate differing heating requirements in different areas by varying the number of heating wires relative to the area and / or the supplied power. This allows areas that need to be cleared of ice and condensation more quickly, or that are more prone to icing due to their layout or position, to receive a higher heating output than areas that are, for example, more sheltered and less prone to icing or moisture fogging. This allows the energy requirement of the proposed heating system to be adapted to the prevailing conditions and / or requirements.

[0017] A further embodiment of the heating device according to the invention consists in that the cross-section of a first busbar is smaller than the cross-section of a second busbar. Since the at least two first busbars each absorb the electrical energy to achieve the heating output proportionally and are connected to the at least one second busbar by means of the heating conductors, the latter must be designed for the total amount of current to be conducted. In order to save material, however, the cross-section of the at least two first busbars, optionally one or more of the first busbars, can be selected to be smaller so that the necessary current can be reliably absorbed and conducted without providing unnecessary cross-sectional area. One or more of the at least two first busbars can therefore be manufactured more cost-effectively because less material is required.

[0018] An alternative or further material saving can be achieved if at least one of the first busbars and / or the second busbars is contacted centrally. One or more of the first busbars and / or one or more of the second busbars should therefore be contacted centrally to connect them to the power supply for the heating system. This allows the amount of conductive material, which could be silver, for example, to be significantly reduced, thus lowering costs.

[0019] It can also be provided that the heating conductors of adjacent heating circuits that are closest to each other are the same distance from each other as the heating conductors of these heating circuits are from each other. Thus, the distance between a heating conductor located externally of the heating circuit and facing an adjacent heating circuit and a corresponding one in the adjacent heating circuit corresponds to the distance between the heating conductors in the two respective heating circuits. This ensures even heat distribution within the pane, even in the area between adjacent heating circuits.

[0020] The window for which the heating device is intended can be a rear window of a vehicle, a windshield of a vehicle, a window in or on a building, and / or a window in or on an infrastructure object. Windshields and rear windows of a vehicle can be heated to ensure the vehicle's drivability in the event of snow, ice, or condensation by heating and thus defrosting them. By shifting the dew point on the window as a result of the heating, fogging can also be reduced or prevented.

[0021] Heated windows are also used in and / or on buildings where heating is required to ensure safe use even in winter weather. The same applies to infrastructure objects, which can include all kinds of signage, and where visibility should not be impaired by moisture, snow, or ice, even in inclement and cold weather.

[0022] A heating device of the type described above can be manufactured by printing the busbars onto a disk using a solution containing silver particles (glass frit), followed by a thermal treatment to harden them. The heating conductors can be manufactured in the same way, preferably in the same step. This type of manufacturing ensures that the busbars are firmly and inseparably connected to the disk. Soldered contacts are usually formed on the busbars, which can be used to connect to the power supply and the electronic fuses. The connection to the power supply is usually made via plug-in connectors.

[0023] The use of the heating device described above for vehicles is particularly preferred, so that a vehicle is also claimed whose windscreen and / or rear screen is formed with the heating device according to the invention.

[0024] The heating device according to the invention allows the use of electronic fuses that protect electrical consumers more quickly, reliably, and with a smaller installation space requirement. By dividing heating circuits in the manner described above, the performance limits of electronic fuses can be taken into account and the number of contacts can be reduced, thus achieving savings in material and thus costs.

[0025] The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless otherwise stated in the individual case.

[0026] The invention is explained below with reference to the accompanying drawing. It shows:

[0027] Figure 1 is a schematic sketch of the heating device according to the invention in an exemplary embodiment.

[0028] As the schematic diagram in Figure 1 shows, a heating device 10 of a disk 20 is formed with two first busbars 30.1 and 30.2 and a second busbar 40, with the busbars 30.1 and 30.2 forming the positive poles and the busbar 40 forming the negative pole. Each first busbar 30.1, 30.2 is connected to the second busbar 40 by means of three heating conductors 50, thus forming two heating circuits 22.1 and 22.2. Within the heating circuits 22.1 and 22.2, the spacing between the heating conductors 50 is identical. The heating conductors 50, which are located on the outside of each of the two heating circuits 22.1, 22.2 and face the other heating circuit 22.2, 22.1, are spaced the same distance apart as the heating conductors 50 within each of the heating circuits 22.1, 22.2. Each of the heating circuits 22.1 and 22.2 is protected by an electronic fuse 60.1, 60.2.2 can be arranged at any point of the electrical supply on the positive pole side.

[0029] The two first busbars 30.1, 30.2 are formed with the same length h, l2 and the same cross-section, so that they are identical to one another. The length h, l2 corresponds approximately to half the length of the second busbar 40, so that the first busbars 30.1, 30.2 can be referred to as half-busbars. The heating circuits 22.1 and 22.2 can therefore be referred to as identical in terms of heating output and geometry. As a result of the electrical power to be conducted in the two heating circuits 22.1, 22.2 being divided between the two heating circuits, the cross-sections of the first busbars 30.1, 30.2 can be smaller than those of the second busbar 40, thereby saving material.

[0030] It is also evident from Figure 1 that the contacts 32.1, 32.2 and 42 of the busbars 30.1, 30.2 and 40 are each made centrally, so that the amount of conductive material can be reduced during production.

[0031] The busbars 30, 40 and the heating conductors 50 are applied to the pane 20 using a printing process with subsequent thermal treatment. It can then be installed, for example, as a rear window of a vehicle. For this purpose, the pane 20 is inserted into a vehicle and glued in place, and then the contacts 32, 42 are connected to the vehicle's electrical wiring using plug connectors.

[0032] List of reference symbols

[0033] 10 Heating device

[0034] 20 slices

[0035] 22 heating circuits

[0036] 30 first busbar 32 Contacting of the first busbar

[0037] 40 second busbar

[0038] 42 Contacting the second busbar

[0039] 50 heating conductors

[0040] 60 electronic fuse I Length of busbars

Claims

Patent claims 1. Heating device (10) for discs (20) with - at least two first busbars (30) as positive poles and - at least one second busbar (40) as negative pole, - wherein the at least two first busbars (30) of the positive poles are connected to the at least one second busbar (40) of the negative pole by heating conductors (50), so that at least two heating circuits (22) are formed, characterized in that each of the heating circuits (22) thus formed is protected by an electronic fuse (60).

2. Heating device (10) according to claim 1, characterized in that it is designed with exactly one busbar (40) as negative pole and exactly two busbars (30) as positive poles.

3. Heating device (10) according to claim 1 or 2, characterized in that the at least two heating circuits (22) are of identical design.

4. Heating device (10) according to one of the preceding claims, characterized in that with the at least two formed heating circuits (22) heating surfaces are formed in a defined shape and / or with different heating effects.

5. Heating device (10) according to one of the preceding claims, characterized in that the cross section of a first busbar (30) is smaller than the cross section of a second busbar (40).

6. Heating device (10) according to one of the preceding claims, characterized in that at least one of the first busbars (30) and / or the second busbars (40) is contacted centrally.

7. Heating device (10) according to one of the preceding claims, characterized in that those heating conductors (50) of adjacent heating circuits (22) which are have the smallest distance, have the same distance from each other as the heating conductors (50) of these heating circuits are from each other. Heating device (10) according to one of the preceding claims, characterized in that the pane (20) is a rear window of a vehicle, a front window of a vehicle, a pane in or on a building and / or a pane in or on an infrastructure object. Method for producing a heating device (10) for a pane (20) according to one of the preceding claims, wherein the busbars (30, 40) are connected by means of a A solution containing silver particles is printed onto a pane (20) and subsequently cured by means of a thermal treatment. A vehicle having a windshield and a rear window, wherein the windshield and / or the rear window is provided with a heating device (10) according to one of claims 1 to 8.

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