Heating device for glazing

Abstract

The invention relates to a heating device (10) for a window pane (20), wherein at least two busbars (30) are designed as a positive pole and at least one busbar (40) is designed as a negative pole and are connected by means of a heating conductor (50). In this way, at least two heating circuits (22) are formed and are each protected by an electronic safety device (60) according to the invention.

Description

[0001] The invention relates to a heating device for window panes, wherein at least two busbars are designed as positive poles and at least one busbar is designed as negative pole and connected via a heating conductor, thereby forming at least two heating circuits which are protected by electronic fuses according to the invention.

[0002] The current requirement for heating a window pane increases in proportion to its size. In this case, a heating circuit is usually formed with two busbars, which form a positive pole and a negative pole, and a heating conductor extending between the two busbars. In the prior art, the heating conductor is usually designed with a fuse in order to protect the heating circuit.

[0003] Electronic fuses are also known to protect circuits. However, these components, also called "digital fuses," are relatively limited in their current carrying capacity. If the current demand of the device exceeds this limit, the current must be divided among a number of subcircuits, the current demand of which is respectively below the limit of the electronic fuse assigned to it. This in turn results in the need for a greater number of contact connections, which leads to higher costs and greater manufacturing effort, since each subcircuit must be connected separately to the energy supply.

[0004] The object of the present invention is therefore to propose a solution by which heating of larger surfaces or panes is also possible using an electronic fuse while being at least cost-effective.

[0005] This object is achieved by a heating device according to claim 1, a method for producing the same according to claim 9 and a vehicle according to claim 10. Further preferred embodiments of the invention result from the features specified in the remaining dependent claims.

[0006] The heating device for window glass according to the present invention is constructed 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 positive poles are connected to the at least one second busbar of negative poles via heating conductors, thereby forming at least two heating circuits, characterized in that each heating circuit thus formed is protected by an electronic fuse device.

[0007] The heating device is thus constructed such that at least two first busbars are provided to provide a positive pole, and at least one second busbar is provided to provide a negative pole, and the first busbars are respectively connected to one or more second busbars of the negative pole via heating conductors. Therefore, the heating conductors respectively start from the at least two first busbars of the positive pole and are connected to the at least one busbar of the negative pole.

[0008] At least two heating circuits are formed here, that is, they are each formed by a region of a first busbar of the positive pole and at least one busbar of the negative pole, into which the heating conductor of the corresponding first busbar passes. It is particularly advantageous here that the number of second busbars on the negative pole is at least one less (the number "1") than the number of first busbars, in order to reduce the number of necessary contact connections with energy input. If, as in the prior art, the busbars of the positive pole are connected to the busbars of the negative pole respectively, two joints are formed in such a heating circuit. If two heating circuits are constructed in this way, four contacts are formed. On the other hand, if the heating conductors are guided from multiple first busbars of the positive pole to at least one second busbar of the negative pole and connected thereto, although each first busbar of the positive pole requires a contact connection, at least one contact connection can be eliminated on the negative pole side, thereby reducing costs and installation costs. The more first busbars are connected to the common second busbar, the greater the potential for savings. However, the corresponding number of first and second busbars is still within the scope of the present invention.

[0009] Each heating circuit in the heating circuit now formed between the first busbar and at least one second busbar is protected according to the present invention by an electronic fuse. An electronic fuse, also commonly known as a digital fuse, is a form of overcurrent protection device, which has a very compact construction and triggers or switches significantly faster than conventional power protection switches, such as thermal magnetic circuit breakers or superfast fuses. In addition, it has no mechanical components and thus has a higher safety against faults. The fuse is now selected to suit the current requirements of the individually designed heating circuit and / or the heating circuit is composed of an appropriate number of first and second busbars so that it does not exceed the load capacity of the electronic fuse. The heating circuit and its protection can thus be divided as required, so that optimization can be achieved in terms of heating power, cost and required installation space.

[0010] With the heating device according to the invention, even large windows, such as increasingly large rear windows of vehicles, can now be heated using digital fuses and the number of necessary contacts and connections can be reduced depending on the design of the heating circuit. This also speeds up and simplifies the production and installation of such windows.

[0011] A particularly preferred design of the heating device according to the present invention is that it has exactly one busbar as the negative pole and exactly two busbars as the positive pole. This design is particularly suitable for heating devices of vehicles, especially rear windows thereof. The two first busbars can form the positive pole here, the second busbar forms the negative pole, and the negative pole is connected to the positive pole via a heating conductor. The two first busbars can also be called half-lines in this configuration if they are the same in size and transmittable power. By dividing into two formed heating circuits, only three contact connections and therefore only three joints are required on the energy supply device, namely one each on the positive pole and one on the negative pole, instead of four, even if the second busbar of the negative pole is shared. This saving can have a great effect precisely in the manufacture of large-volume items or large-volume products.

[0012] It is also advantageous if at least two heating circuits are designed identically. This is to be understood as meaning that the components and in particular the first busbars are identical to one another and / or the second busbars are identical to one another in terms of size and transmittable power. This simplifies and speeds up production, since busbars of different types, sizes and designs do not have to be produced and tested. The busbars in heating devices of the type mentioned above are usually printed, so that only one printed pattern can be used for all busbars of the same type.

[0013] However, in some applications, the same type of design of at least two heating circuits is unreasonable or undesirable, for example, because there are areas with different heating requirements. It may be suitable to form a defined shape and / or a heating surface with different heating effects by at least two formed heating circuits.

[0014] In this context, a defined shape is understood to mean any other shape that produces a difference in shape and / or size between at least two heating circuits. Thus, for example, the shape of a window pane and the shape of an object protected by the window pane can be followed. However, geometric shapes and patterns can also be designed in a targeted manner, which are formed by the heating circuits with the aid of busbars and heating conductors and can thereby produce decorative effects that are visible when the heating device is in use. However, the shape can also take into account different heating requirements and in particular be combined with different heating powers.

[0015] The design of different heating surfaces can take into account regionally different heating requirements by varying the number of heating wires and / or the power input relative to the area. Thus, areas that require faster removal of ice and water vapor or areas that are subject to more severe ice formation due to their arrangement or location can be subjected to a higher heating power than areas that are, for example, arranged in a protected manner and are less subject to severe ice formation or less subject to moisture. Thus, the energy requirement of the proposed heating device can be adapted to the prevailing conditions and / or requirements.

[0016] Another design of the heating device according to the present invention is that the cross-section of the first busbar is smaller than the cross-section of the second busbar. Since the at least two first busbars absorb the electrical energy for realizing the heating power in proportion and are connected to the at least one second busbar through the heating conductor, they must be designed according to the total amount of current to be conducted. However, in order to save material, the cross-section of the at least two first busbars, and optionally one or more of the first busbars, can be selected to be smaller so that the required current can be safely absorbed and conducted, but no unnecessary cross-sectional area is provided. As a result, one or more of the at least two first busbars can be manufactured more cost-effectively because less material is required.

[0017] An alternative or additional 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 be contacted centrally in order to connect them to the energy supply for heating. This can significantly reduce the amount of conductive material, for example silver, and reduce costs.

[0018] It can also be provided that the heating conductors of adjacent heating circuits that are at the shortest distance from one another have the same distance from one another as the distance between the heating conductors of these heating circuits. Thus, the distance between a heating conductor that is located outside with respect to the heating circuit and faces the adjacent heating circuit and the corresponding heating conductor in the adjacent heating circuit corresponds to the distance between the heating conductors in the two heating circuits in question. This makes it possible to ensure a uniform heat distribution in the window pane even in the region between adjacent heating circuits.

[0019] The heating device is provided for a window pane, which may be a rear window pane of a vehicle, a front window pane of a vehicle, a window pane in or on a building and / or a window pane in or on an infrastructure object. The front window pane and the rear window pane of a vehicle can be heated in order to make the vehicle ready for driving in the case of snow, ice or moisture by heating them and thereby thawing them. By changing the dew point on the window pane by heating, condensation of water vapor can also be reduced or avoided.

[0020] However, heated window panes are also used in and / or on buildings, where the heating should ensure safe use in winter weather. The same applies to infrastructure objects, which can also include all types of signage, where the view of the signage should not be impaired by moisture or ice and snow even in inclement and cold weather.

[0021] A heating device of the type described above can be produced by printing the busbars onto the window pane using a solution containing silver particles (glass paste) and then curing them by heat treatment. The heating conductors can be produced in the same way, preferably in the same steps. This production method secures and inseparably connects the busbars to the window pane. Contacts, which are usually soldered, are formed on the busbars, which allow connection to the energy supply device and to the electronic fuse. The connection to the energy input device is usually made via a plug connection.

[0022] The above-described heating device is particularly preferably used in a vehicle, and therefore protection is also claimed for a vehicle whose windshield and / or rear window is provided with a heating device according to the invention.

[0023] The heating device according to the invention allows the use of electronic fuses which protect the load more quickly, more reliably and with less installation space. By dividing the heating circuit in the above-described manner, the power limits of the electronic fuses can be taken into account and the number of contact connections can be reduced, so that material and thus costs can be saved.

[0024] The various embodiments of the invention mentioned in this application can be advantageously combined with one another, unless otherwise stated in the individual cases.

[0025] The present invention is described below with reference to the accompanying drawings. In the accompanying drawings:

[0026] Figure 1 A schematic diagram shows a heating device according to the invention in an exemplary design.

[0027] As in Figure 1 As shown in the schematic diagram in FIG. 1 , the heating device 10 for the window pane 20 is designed with two first busbars 30.1 and 30.2 and a second busbar 40, wherein the busbars 30.1 and 30.2 form the positive pole and the busbar 40 forms the negative pole. The first busbars 30.1 and 30.2 are connected to the second busbar 40 via three heating conductors 50, respectively, thereby forming two heating circuits 22.1 and 22.2. In the heating circuits 22.1 and 22.2, the distances between the heating conductors 50 are respectively the same. The heating conductors 50 located on the outside of the two heating circuits 22.1 and 22.2 and facing the other heating circuit 22.2 and 22.1 respectively have the same distance as the heating conductors 50 in the heating circuits 22.1 and 22.2.

[0028] Each heating circuit 22.1 and 22.2 is protected by an electronic fuse 60.1, 60.2. The electronic fuse 60.1, 60.2 can be arranged at any position of the power supply device on the positive side.

[0029] The two first busbars 30.1, 30.2 are constructed with the same length l1, l2 and the same cross section, so that they are identical to each other. The length l1, l2 corresponds to approximately half the length of the second busbar 40, so the first busbars 30.1, 30.2 can be called half-lines. Therefore, the heating circuits 22.1 and 22.2 can be called identical in terms of heating power and geometry. Due to the electrical power to be performed in the two heating circuits 22.1, 22.2, the cross section of the first busbars 30.1, 30.2 can be smaller than the cross section of the second busbar 40, thereby saving material.

[0030] Depend on Figure 1 It can also be seen that the contact connections 32 . 1 , 32 . 2 and 42 of the busbars 30 . 1 , 30 . 2 and 40 are each centrally realized, so that the amount of conductive material can be reduced during production.

[0031] The busbars 30, 40 and the heating conductor 50 are applied to the window pane 20 in a printing method by subsequent heat treatment. The window pane can then be installed, for example as a rear window pane of a vehicle. To this end, the window pane 20 is installed in the vehicle and bonded, and then the contact points 32, 42 are connected to the electrical lines of the vehicle via plug connections.

[0032] Reference numerals list

[0033] 10 Heating device

[0034] 20 Window Glass

[0035] 22 Heating circuit

[0036] 30 First busbar

[0037] 32 Contact connection part of the first busbar

[0038] 40 Second busbar

[0039] 42 Contact connection part of the second busbar

[0040] 50 Heating conductor

[0041] 60 Electronic safety device

[0042] l Length of busbar

Claims

1. A heating device (10) for a window glass (20), the heating device having - at least two first busbars (30) as positive electrodes and - at least one second busbar (40) as a negative pole, - wherein at least two first busbars (30) of the positive electrode and at least one second busbar (40) of the negative electrode are connected via a heating conductor (50) to form at least two heating circuits (22), It is characterized in that Each heating circuit (22) formed in this way is protected by an electronic fuse (60).

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

3. The heating device (10) according to claim 1 or 2, characterized in that: The at least two heating circuits (22) are designed to be identical.

4. The heating device (10) according to any one of the preceding claims, characterized in that By forming at least two heating circuits (22), a heating surface of defined shape and / or having different heating effects is formed.

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

6. The heating device (10) according to any one of the preceding claims, characterized in that At least one of the first busbar (30) and / or the second busbar (40) is contacted centrally.

7. The heating device (10) according to any one of the preceding claims, characterized in that The heating conductors (50) of adjacent heating circuits (22) which have the smallest distance from one another have the same distance from one another as the distance between the heating conductors (50) of the heating circuits.

8. The heating device (10) according to any one of the preceding claims, characterized in that The window pane (20) is a rear window pane of a vehicle, a front window pane of a vehicle, a window pane in or on a building and / or a window pane in or on an infrastructure object.

9. A method for producing a heating device (10) for a window pane (20) according to any one of the preceding claims, wherein: The busbars (30, 40) are printed on the window glass (20) from a solution containing silver particles and then cured by heat treatment.

10. A vehicle having a front window glass and a rear window glass, wherein: A front window and / or a rear window is provided with a heating device (10) according to any one of claims 1 to 8.

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