DE102005032698A1 - Windscreen wiper for vehicle, has electrical resistance-based heater for heating wiper, and heating wire passed in hollow space existing between wiper rubber and wiper housing for supplying heat into wiper construction and wiper rubber - Google Patents

Abstract

The wiper has an electrical resistance-based heater for heating the wiper, where the power to the heater is acquired by inductive coupling between a retainer and a windscreen wiper arm by using a water-tight plug connector. A heating wire (4) is passed in a hollow space existing between a wiper rubber (2) and a wiper housing (1) for supplying heat into a wiper construction and the wiper rubber, where the wiper rubber is connected with the housing by using spring rails.

Description

By low outside temperatures Wiper rubbers are influenced in the way that suppleness of the rubber and thus wiping results. Either will not more all areas of the disc in the desired shape edited (z. B. Removal of precipitate) or it comes when wiping to a "rubbing" on the disc, by the windshield wiper in part only in small jumps over the Disc moves. The wiping result shows clearly in the quality, which results in a visual obstruction and thus a security risk represents. Furthermore, by clinging to ice and snow, the windscreen wiper also in its adaptability affected by the disc become, what to similar Disadvantages as described above. The attachments of ice and snow can on the one hand by rainfall be caused. Another cause is in the winter too Example of the use of de-icing salt or the short-term defrost of Ice and snow on streets (eg due to sunshine). Thus, it comes to the presence of Water on roads, despite that the outside temperatures below or around the freezing point. This meltwater is upset by preceding vehicles and to the windscreen your own vehicle thrown. When wiping the discs sets This water then in grooves and on the windshield wiper itself solidifies and freezes again after some time, resulting in the above Problems leads. Likewise, wet snow or snow thawed for a short time or ice (eg thawed by disc heaters) on the windscreen wiper and also cause the problems described above.

windshield wipers are heated only indirectly so far. Either that happens through a heated windscreen (eg at Ford), by specifically in the Slice of heated parking areas the windscreen wiper (eg Lexus) or by an expensive supply of Hot water z. B. from the cooling circuit (Run Bullis). Another approach to solving this problem is the feed (blown) with hot air (direct or indirect). The electrical indirect heating of the windscreen wiper over the windscreen is not sufficient for the solution of the problem described above. It only prevents freezing the rubber on the disc. A heating by hot water is with high installation costs and other problems connected (freezing of water, leakage of hoses, maintenance, etc.) which leads to a disqualification for mass production. The Heating of the wiper by hot air (blowing) also leads to too little energy input to the wiper is also associated with high installation and maintenance, is through the airstream has a very negative influence and has further problems (Add the air nozzles, Leaks, etc.) which also to a disqualification for mass production use leads.

Problem to be solved

Of the This invention is based on the problem of wipers to prevent freezing and freezing and to maintain suppleness the wiper easy to maintain, effective, inexpensive, suitable for everyday use (Operation by non-specialist personnel) and suitable for mass production too heat.

In order to heat a windshield wiper and achieve the desired effect, an electric resistance-heated variant of the windscreen wiper is selected as in claims 3 to 8, wherein a heating wire as in 1 ( 3 ), is placed in a cavity of the windshield wiper or as in 2 ( 6 ) a heating wire is integrated into the wiper rubber or the wiper rubber itself is made of a conductive material, where electrical energy can be converted into heat or the spring plates (as in 1 ( 3 ) and 2 ( 7 ) are themselves made of electrically conductive material or combined with a heating wire or a heating wire in an outer cavity of the windscreen wiper rubber 2 ( 8th ) is spent.

As a transmission variant, a contactless transmission according to claim 1 is selected 3 , A coupling element (core) 3 ( 10 ) is on the wiper arm 3 ( 14 ) attached. To this coupling element 3 ( 10 ) becomes the electrical circuit of the primary circuit 3 ( 9 ) attached. On the wiper rubber 3 ( 12 ) is the electrical circuit of the secondary circuit 3 ( 11 ) from which the contact to the heating wire 3 ( 13 ) is produced in the variants described above.

For the in 3 schematically illustrated construction, there are two variants: a flyback converter and a flux converter.

Flyback converter:

The necessary, closed core requires a special construction of the mop head. When the core is opened, ie while changing the wiper blade, the load is shed, because the main inductance (Lh) is extremely reduced. The primary current increase increases extremely, so that a current control - also called current-control-mode (CCM) - is required to self-destruct to prevent the circuit. The CCM control can only be meaningfully adopted by a control IC, which has a negative impact on the cost side. The enormous increase in current in the upper kHz range also amplifies the EMC interference radiation, which in turn requires cost-increasing EMC filters.

Flow converter:

by virtue of its switching frequency needed this topology does not have a closed core but only one open coupling element for energy transmission. Is used a special flux-transducer topology, with a switching frequency in the MHz range. While in the flyback converter, the energy is stored in the core, Essentially, the core of the flux converter serves only for coupling. There Nevertheless, energy is temporarily stored in the core during load shedding This must be done by a special circuit topology back in the Supply circuit are pushed. The current increase changes When opening of the mop head only insignificantly, since the core geometry is not changed and the factor Lh / Ls is much smaller. At the mop head needed It does not have any special construction, just a simple rod used with corresponding magnetic properties as a core can be. The control of the transformer can Using a simple RC oscillator done what the space and cost significantly reduced.

The transfer can also be achieved by a simple wire attached to the wiper arm respectively. This is separable on a protected against water coupling, so a wiper change is readily possible.

Advantages of invention

Of the relatively low Cost of the invention allows an economic utilization in large series. Through the used Circuit topology is expected with no / minimal interference, which also leads to a suitability for the automotive sector. The contactless or sufficiently secure against water transmission is weather resistant, In particular, these variants provide sufficient protection against corrosion. The design features allow operation by non-specialist personnel and only need a minimal amount of time during installation. The treatment the load shedding problem by design details or used Circuit topologies enabled a practical use without special elaborate protective measures or operating instructions.

drawings

In The drawings are exemplary embodiments shown. The drawings, the description and the claims contain numerous features in combination. The skilled person will become the characteristics expediently also consider individually and summarize to meaningful combinations. The Drawings contain in part only schematic representations that shown in more detail in an exact design drawing 7 become. In the attached Drawings are not all claims represented.

1 : It is shown a wiper cross-section, wherein between wiper blade ( 2 ) and wiper housing ( 1 ) a cavity exists. In these, a heating wire ( 4 ) to get integrated. This then transmits the resulting heat to the wiper rubber during commissioning ( 2 ), which via spring rails ( 3 ) is connected to the housing.

2 : It's a wiper rubber ( 5 ) is shown on the spring plates ( 7 ) to stabilize the wiper or to connect it to the carrier. On the carrier was omitted in this presentation. In the windscreen wiper rubber are exemplified heating wires ( 6 ) integrated. In the cracks ( 8th ) or recesses ( 8th ) in the wiper rubber can also run heating elements, but this is also not shown.

3 : It is a wiper arm ( 14 ), on which a coupling element (core) ( 10 ) is attached. To the coupling element ( 10 ) on the wiper arm ( 14 ) is the electrical circuit of the primary circuit ( 9 ). On the wiper blade ( 12 ) is the electrical circuit of the secondary circuit ( 11 ). With this, the lines to the heating elements ( 13 ) or the heating elements ( 13 ) attached itself.

Claims (9)

Windscreen wiper for vehicles characterized in that it can be heated by means of electrical (resistance-based) heating. Windscreen wiper according to claim 1, characterized that the energy by means of contactless transmission (inductive coupling between bracket / windscreen wiper arm and windscreen wiper) in the Windscreen wiper arrives. Windscreen wiper according to claim 1, characterized that the transmission the energy by means of waterproof connector in the windscreen wiper arrives. Windscreen wiper according to claim 1, characterized that a resistance wire spent in cavities of the windscreen wiper is going to heat into the wiper construction and the wiper rubber derive. Windscreen wiper according to claim 1 characterized that a resistance wire is spent in windscreen wiper scratches, for heat into the wiper construction and the wiper rubber derive. Windscreen wiper according to claim 1 characterized that a resistance wire is placed in the wiper rubber itself, to heat in derive the wiper construction and the wiper rubber. Windscreen wiper according to claim 1, characterized in that a resistance wire in the spring or the stabilizing sheet The wiper is spent to heat in the wiper design and derive the wiper rubber. Windscreen wiper according to claim 1 characterized that as a heatable resistance element, the spring or the stabilizing sheet the windscreen wiper itself is used by a conductive suitable Material used as a sheet to add heat to the wiper design and derive the wiper rubber. Windscreen wiper according to claim 1 characterized that as a heatable resistance element of the wiper rubber (conductive plastic) The wiper itself is used to heat in the entire wiper design and derive the wiper rubber.