DE202020005399U1 - Lens hood for an image capture device for a motor vehicle - Google Patents

Abstract

Lens hood (1) for an image capturing device (4) arranged on the back (2) of a windshield (3) with a shielding wall (5) which is set up for a viewing area (6) of the image capturing device (4) between the image capturing device (4) and shield the windshield (3) at least partially from incident stray light (7), characterized in that the shielding wall (5) at least in a section (8) which is oriented towards the windshield (3) on one of the viewing area (6) opposite outside of the shielding wall (5) is flatly connected to a base body (23), the base body (23) being made of an electrically conductive plastic with PTC properties, on which electrical conductive structures (9) are arranged for energizing the electrically conductive plastic .

Description

The invention relates to a lens hood of an image acquisition device arranged on the rear side of a motor vehicle windshield.

This lens hood forms, in particular, an arrangement for heating a viewing window for the image capture device.

Modern vehicles are increasingly being equipped with assistance and safety systems which are based in particular on image capture devices. Information relating to the surroundings of the motor vehicle captured by image capturing devices is processed in the motor vehicle in order to enable the assistance and safety systems to be operated as intended. In order for the assistance and safety systems to function as intended, the field of vision of the image capture devices must not be disturbed. However, this can be done by fogging up a viewing window of the image capturing devices, for example by water droplets or ice, which can occur in particular at low temperatures.

A position which is particularly suitable for the arrangement of image capturing devices for various reasons is the position in the vehicle behind the windshield. An image acquisition device arranged there has a similar field of vision as the driver and can therefore provide particularly suitable information for the operation of assistance and safety systems in the vehicle.

Proceeding from this, it is the object of the present invention to at least partially solve the problems described with reference to the prior art. In particular, a lens hood is to be specified which at least contributes to enabling safe operation of the sensor even at low ambient temperatures. In addition, the lens hood should be inexpensive to manufacture.

What is to be described here is a lens hood for an image capturing device arranged on the back of a windshield with a shielding wall, which is set up to at least partially shield a viewing area of the image capturing device between the image capturing device and the windshield from incident stray light Section which is oriented towards the windshield is flatly connected to a base body on an outside of the shielding wall opposite the viewing area, the base body being made of an electrically conductive plastic with PTC properties, on which electrical conductive structures for energizing the electrically conductive plastic are arranged.

The image acquisition device is in particular a camera with an objective and a sensor with a sensor or film surface, which is arranged behind the objective. The lens can be a zoom lens.

The viewing area describes, in particular, a space in front of the image capturing device (in particular in front of its lens) which, starting from the image capturing device, expands towards the windshield. The viewing area is thus usually prism-shaped and, if necessary, also funnel-shaped. The term windshield usually refers to the front window of a motor vehicle. The lens hood described here is, however, suitable for use behind every window - in particular also for use behind rear windows of a motor vehicle, which are often alternatively referred to as rear windows.

A suitable geometry of the lens hood depends on the angle at which an image capturing device and in particular an objective of the image capturing device looks through the windshield. A suitable geometry also depends on the diameter of the front lens of the objective and the size of the sensor or film surface of the image acquisition device. A lens with a small angle of view usually has a longer lens hood than a lens with a large angle of view. Lens hoods for zoom lenses are always designed for the shortest focal length (largest angle of view) and for the largest possible sensor or the usable image circle of the lens. The use of lenses designed for the small image format on image capturing devices with smaller image sensors, for example in the APS-H or APS-C format, however, usually enables the use of larger lens hoods with a better effect.

The wrong design of the lens hood either leads to a reduced protective effect if it is too short or to the shading of the detection area or its edge area (vignetting) if it is too long or too small in diameter. When using additional filters, screw-in bezels, in particular with wide-angle lenses, can lead to further vignetting of the detection area and in particular its edge area.

According to an advantageous embodiment, it is proposed that the electrically conductive plastic is a polymer material with PTC resistance properties (PTC = positive temperature coefficient; in German: positive temperature coefficient).

The lens hood is preferably adapted to the image capturing device in such a way that no vignetting occurs and a sufficient protective effect is achieved.

The electrically conductive plastic can be, for example, an intrinsically conductive polymer (or an intrinsically conductive plastic). In other words, this means in particular that the electrically conductive polymer material is one that is itself electrically conductive. Alternatively or cumulatively, it can be provided that the electrically conductive polymer material is electrically conductive by at least one electrically conductive additive or filler, such as aluminum flakes or carbon black, which is contained or embedded in a (not necessarily itself conductive) polymer. The electrically conductive plastic particularly preferably has a matrix made of polyethylene or a similar material. The electrically conductive plastic is preferably soft compared to a material of the shielding wall.

A change in the structure of the electrically conductive plastic preferably takes place at a switching temperature, which leads to the fact that electrically conductive paths in the electrically conductive plastic are deactivated and thus the conductivity in the range of the switching temperature drops sharply.

If the resistance value of a material increases with increasing temperature, the resistance of the material has a positive temperature coefficient. Materials with metal-like conductive properties generally have a positive temperature coefficient with regard to their electrical resistance (PTC properties or PTC resistance properties). With conductive properties similar to metal, the resistance increases almost linearly with increasing temperature. In contrast, electrically conductive polymer materials usually have a strong increase in resistance in a very narrow temperature range. In general, these polymer materials are also abbreviated to PPTC. Here the PPTC stands for the English term Polymer Positive Temperature Coefficients.

In other words, the electrically conductive polymer material with PTC resistance properties can in particular also be described as what is known as a (polymer) PTC thermistor. A PTC resistor, PTC resistor or PTC thermistor is a temperature-dependent resistor that belongs in particular to the group of thermistors. As a property, it has a positive temperature coefficient and conducts electrical current better at low temperatures than at high temperatures.

Many vehicles, airplanes, helicopters and ships are equipped with various image capture devices / optical sensors. The lens hood described here is in principle suitable for all types of vehicles and optical sensors.

The shielding wall preferably consists of a different material than the material of the electrically conductive plastic and in particular a different material than the matrix material of the electrically conductive plastic. The shielding wall particularly preferably consists (predominantly) of a polyamide or a similar material. The shielding wall is preferably relatively hard or stiff compared to the electrically conductive plastic. This has the advantage that an increased rigidity of the shielding wall is guaranteed and, in particular, it does not deform under the influence of temperature. In addition, structures for fastening the lens hood to other components can better be provided on a wall made of a relatively hard plastic, such as polyamide. Latching lugs or similar fastening structures are preferably molded directly onto the shielding wall.

The section of the base body oriented towards the windshield forms, in particular, a base of the lens hood, which is arranged opposite the windshield. The base body is flatly connected to the shielding wall on an outside of the shielding wall opposite the viewing area. The base body is preferably not completely integrated into the shielding wall, but there is preferably a free surface of the base body which is oriented outwards (away from the viewing area) and in which the electrically conductive plastic is exposed.

The base body preferably covers at least 60 percent of a total area of the shielding wall. The flat connection between the base body and the shielding wall is in particular a material connection between the electrically conductive polymer material and the material of the shielding wall, which extends along the shielding wall.

It is advantageous if the base body consists of at least 40 percent by weight of the electrically conductive plastic with PTC properties.

The remaining percent by weight is preferably allotted to electrical contacts and, if necessary, to coatings etc.

The base body preferably has a thickness (in the direction perpendicular to the surface) of between 0.5 mm [millimeters] and 5 mm [millimeters].

The electrically conductive plastic with PTC effect is preferably designed so that it has a switching temperature between 40 ° and 90 °. As a result, temperatures of the lens hood can be reached in this area. A maximum operating temperature of the lens hood is preferably in the range of the switching temperature or slightly above. Temperatures in this temperature range can remove moisture from the lens hood. This applies in particular to moisture that has deposited on an area of a windshield positioned above the lens hood or has condensed there. A local increase in the temperature in the area of the lens hood can, in particular, improve the air's ability to absorb moisture and improve the removal of moisture. In addition, temperatures in this temperature range are also suitable for generating thermal radiation which, starting from the lens hood, radiates in the direction of the windshield and thus causes local heating of the windshield. In this way, the temperature of the windshield can be increased and the formation of condensation on the windshield in the area of the lens hood can be prevented.

It should also be described here that at least two electrical conductive structures that are separate from one another are arranged at least on the base body.

The electrical conductive structures are preferably metallic and in particular metallic sheet-metal elements, for example made of copper, silver or aluminum and / or coated with copper, silver or aluminum, for example. The electrically conductive plastic can be subjected to a voltage by means of two electrical conductive structures that are separate from one another. In this way, an electrical current flow (heating current) can be generated through the electrically conductive plastic. This generates heat in the electrically conductive plastic.

In principle, a distance between the at least two electrical conductive structures separated from one another in the plastic material is a parameter with which the necessary electrical voltage for producing a desired heating current can be set. The distance is preferably in a range between 1 mm [millimeters] and 10 mm [millimeters].

It is also advantageous if the at least two electrical conductive structures that are separate from one another form comb structures that engage one another at least in regions.

In the case of comb structures, there is a small distance between the at least two electrical conductive structures that are separated from one another. Such comb structures are particularly suitable when a particularly uniform distribution of electrical current on the plastic material is desired. In addition, such comb structures can ensure that only relatively short paths for the electrical current occur through the plastic and thus the operating voltage of the heater can be kept in a low range.

It is particularly preferred that the shielding wall is made of an electrically insulating plastic material.

Such a plastic makes it possible that electrical current does not pass from the base body into further areas of the shielding wall.

In addition, a modulus of elasticity of the material of the shielding wall is preferably at least five times as high as a modulus of elasticity of the electrically conductive plastic with PTC properties at room temperature. Temperatures in the order of approx. 20 ° C are assumed here as room temperature.

In particular, the modulus of elasticity of the material of the shielding wall is so high that latching noses or similar structures for attaching the lens hood to other components made of the same material can be molded onto it without any problems. Such structures can be produced particularly efficiently by this measure.

A plug is preferably molded onto the lens hood. The electrical conductive structures particularly preferably form electrical contact pins of the plug. In particularly preferred design variants, the electrical conductive structures end directly in this connector. A power supply cable for supplying the heater with electrical energy can particularly preferably be plugged into the plug. The electrical conductive structures can directly form pins in a plug. A (separate) cable for making electrical contact with the electrically heatable lens hood can thus be dispensed with.

It is preferred if the plug has a plug housing which is made from the material of the shielding wall.

For example, a sheathing of the plug can be formed as a plug housing from the material of the shielding wall.

In a further preferred embodiment, the electrical conductive structures are arranged on a connecting surface of the shielding wall and the base body.

It is also advantageous if the section forms a surface which forms an angle of at most 20 ° to a surface of the windshield. The angle is particularly preferably even smaller than 18 ° and possibly even smaller than 16 °.

Due to a small angle, there is a relatively large wall section of the lens hood, which is formed opposite the windshield. The base body is arranged on this section and connected to the shielding wall. In this way, a relatively large section of the windshield can be heated. As a result of this arrangement, the base body is also aligned with the windshield in the aforementioned angular range.

It is particularly advantageous if the shielding wall has a structure at least in the area of the section on the side oriented towards the viewing area.

The structure may have a wave shape. The structure is particularly favorable for the two objectives “heat transfer to the windshield” and “minimization of scattered light”.

If necessary, in addition to a first structure for minimizing the scattered light, there can also be an additional (superimposed) second structure which is particularly suitable for particularly good heat transfer or for transferring heat. This second structure is preferably without a significant effect on the scattered light and brings about a further increase in the surface for the heat transfer, for example through a roughness with a particularly short period or the like.

The structure is thus arranged between the base body and the viewing area. The shielding wall is particularly preferably made thin in the area of the structure and the base body (in the section), in particular thinner than in other wall areas such as, for example, wall sections extending laterally upward.

It is also preferred if a surface of the structure is at least 20 percent larger than a surface on the side of the shielding wall facing away from the viewing area.

The side of the shielding wall facing away from the viewing area is preferably smooth. A preferred heat dissipation in the direction of the windshield can be brought about by an enlarged surface towards the inside or towards the windshield.

It is also advantageous if the shielding wall is designed with a base and two side walls laterally adjoining the base, the viewing area being arranged between the two side walls and the section being formed by the base.

The base body is preferably connected to the shielding wall in the area of this base.

If necessary, the inner side of the shielding wall or the lens hood (oriented towards the windshield) can have a shape with rounded corners, which has, for example, an inner radius of between 1 mm [millimeters] and 5 mm [millimeters].

1. A) Feststellen eines Beheizungsbedarfs und dauerhafte Bestromung der elektrischen Leitstrukturen, um einen Heizeffekt in dem elektrisch leitfähigen Kunststoff hervorzurufen,
2. B) Feststellen, dass der Beheizungsbedarf endet und Deaktivierung der dauerhaften Bestromung,

The aim here is also to describe a method for heating the viewing area of an image acquisition device with a lens hood described above, comprising the following steps:

1. A) Determination of the need for heating and permanent energization of the electrical conductive structures in order to produce a heating effect in the electrically conductive plastic,
2. B) Establishing that the need for heating ends and deactivating the permanent power supply,

All of the above advantages and design variants of the lens hood can be used and transferred to the method.

The determination of the need for heating in step A) can be carried out using various measures. One possible measure for determining a heating requirement is the detection of moisture with a moisture sensor, which can be arranged, for example, in a receptacle of the lens hood. A moisture sensor arranged in this way is able to detect local moisture in the field of vision between the lens hood and the windshield. A moisture sensor, which is used to detect moisture to determine a need for heating in step A), can also be arranged at a different location. One variant is to determine the humidity at another point in the interior of the vehicle. Another variant is a moisture sensor that detects moisture outside the vehicle.

A temperature sensor can also be used to determine the need for heating in step A). A to determine the The temperature sensor used when there is a need for heating can, for example, detect an outside temperature. Several temperature sensors can also be used to determine the heating requirement in step A). One possible combination is an externally arranged temperature sensor and an internally arranged temperature sensor, with combined temperature information from these two sensors being used to determine whether there is a need for heating.

A permanent energization in step A) means in particular that the energization is not interrupted for a time interval in which the heating is necessary in order to regulate the heating output. The heating power is regulated in step A) in particular exclusively via the PTC effect of the plastic material and thus within the lens hood. The lens hood heating according to the method described is thus regulated in a purely passive manner.

Deactivation for reasons other than regulating the heating power is possible in the context of step A), but not usual. Deactivation can take place temporarily, for example to carry out a temperature measurement.

It is particularly preferred if there is no temporary interruption of the permanent current supply during step A). This means, in particular, that when a heating requirement is detected, the lens hood is supplied with a constant operating voltage, which permanently leads to a heating current, which is then automatically regulated down when the operating temperature is reached that no further increase in temperature takes place. Only when it has finally been determined that there is no longer any need for heating does deactivation take place, i.e. an interruption of the constant operating voltage. The determination that there is no longer a need for heating (step B)) is preferably made with the same sensor system with which a heating need was also determined in accordance with step A).

In particular, a particularly easy-to-regulate heating of the lens hood can be achieved by this method management in combination with the lens hood described.

The method is particularly preferably carried out in such a way that a particularly low EMC (EMC = electromagnetic compatibility) and thus also an EMC reduction occurs. In particular, there is a particularly low emission of electromagnetic fields from the lens hood. This can be achieved in particular by the described continuous current supply in step A). This continuous current can be supplied with a direct current. In the case of otherwise common electrical heating concepts, on the other hand, alternating fields or alternating voltages often occur, which are also caused in particular by the fact that the heating system has to be switched on and off repeatedly to regulate the heating temperature. This type of continuous current supply is particularly advantageous as an option for EMC relief because the lens hood is arranged in the direct vicinity of the image acquisition device, which is particularly critical for EMC loads.

1. a) Bereitstellen einer Spritzgussform,
2. b) Einlegen von elektrischen Leitstrukturen in die Spritzgussform, derart, dass die elektrischen Leitstrukturen von der Spritzgussform beabstandet und/oder fixiert sind,
3. c) Spritzgießen von elektrisch leitfähigem Kunststoff mit PTC-Eigenschaften in die Spritzgussorm, so dass ein Grundkörper mit daran angeordneten elektrischen Leitstrukturen entsteht,
4. d) Durchführen eines zweiten Spritzgussprozesses zur Herstellung der Abschirmwand derart, dass diese in einem Abschnitt flächig mit dem Grundkörper verbunden ist.

In addition, a method for producing a described lens hood is to be described here, which has at least the following steps:

1. a) Providing an injection mold,
2. b) inserting electrical conductive structures into the injection mold in such a way that the electrical conductive structures are spaced apart from and / or fixed from the injection mold,
3. c) Injection molding of electrically conductive plastic with PTC properties in the injection molding standard, so that a base body with electrical conductive structures arranged on it is created,
4. d) Carrying out a second injection molding process for producing the shielding wall in such a way that it is connected to the base body over a surface in one section.

In step b) it may be necessary for conductive structures to be inserted into the injection mold in such a way that the electrical conductive structures are either spaced apart from the injection mold or are fixed at least on one side. This can be done, for example, by domes which are formed on the injection mold and hold the electrical conductive structures at a distance or fixed from the regions of the injection mold that define the wall surfaces of the lens hood. Dome of this type may result in production-related holes in the base body, which can be subsequently overmolded. A “spaced” insertion of the electrical conductive structures means in particular that the conductive structures rest, for example, on domes in the injection mold, so that the injection molding material (except for the area of the domes) can be positioned completely around the electrical conductive structures. A “fixed” insert means, for example, that the guide structures lie flat in the injection mold and are thus located on the connecting surface between the base body and the shielding wall after the lens hood has been completed.

The electrical conductive structures are preferably provided in the form of a single metal part which has provided separating sections. Because the provided separating sections are interrupted, the metal part results in two electrical conductive structures that are separate from one another. The individual metal part preferably also forms the contact pin of a plug, via which the lens hood can be supplied with electricity for heating. The separation sections are preferably separated between step c) and step d) or even after step d).

Step c) is preferably carried out with a first injection molding tool or an injection mold into which the electrical conductive structures are inserted before the electrically conductive plastic is injected.

Step d) is preferably carried out with a second injection molding tool or injection mold into which the base body is inserted before the material of the shielding wall is injected. The planar contact occurs preferably during step d).

In variant embodiments of the method, the interruption or removal of the separating sections can also take place before step b) or between steps b) and c). In the case of separation before step b), two separate conductive structures are inserted and the separating sections serve to provide two mutually associated conductive structures together. In the case of the separation between step b) and step c), the positioning of the guide structures with respect to one another can still be ensured by the separating sections. Separation can then take place in the injection mold, for example by means of a punching process.

If the interruption or removal of the separating sections takes place between steps c) and d), this can also take place in one of the injection molding tools / injection molds. In this way, additional work steps can be reduced.

The injection mold used in step c) and the (further) injection mold used in step d) for the second injection molding process can also be formed by a common injection molding tool, the electrically conductive plastic with PTC properties and the material for producing the shielding wall being combined one after the other Mold with a variable shape can be injected.

In variant embodiments of the method, method steps c) and d) can also be carried out in the reverse order. The electrical conductive structures are then preferably already fixed by the material of the shielding wall when the (second) injection molding process was carried out first. The electrically conductive PTC polymer material of the base body is then injected on in a subsequent step (first injection molding process). The material of the base body is then injection molded onto an outer side of the shielding wall facing away from the viewing area. The material of the shielding wall then covers the surface of the electrical conductive structures preferably only in sections for fixation so that the free surface of the electrical conductive structures remaining after the production of the shielding wall can come into contact with the PTC polymer material of the base body.

• 1: ein Kraftfahrzeug mit einer ersten Ausführungsvariante einer beschriebenen Streulichtblende;
• 2: ein Kraftfahrzeug mit einer zweiten Ausführungsvariante einer beschriebenen Streulichtblende;
• 3: eine beschriebene Streulichtblende in einer Ansicht von oben mit einem Bilderfassungsgerät;
• 4 eine beschriebene Streulichtblende in einer Ansicht von unten mit einem Bilderfassungsgerät;
• 5: einen Querschnitt durch einen Abschnitt einer Abschirmwand mit dem Grundkörper einer beschriebenen Streulichtblende;
• 6: ein Beispiel für Leiterstrukturen einer beschriebenen Streulichtblende;
• 7: ein Ablaufdiagramm des beschriebenen Verfahrens;
• 8a bis 8c: den Grundkörper bzw. dessen Vorprodukte in verschiedenen Stationen der Herstellung; und
• 9: einen Querschnitt durch einen Abschnitt der Abschirmwand mit dem Grundkörper einer beschriebenen Streulichtblende in speziellen Details.

The solution presented here and its technical environment are explained in more detail below with reference to the figures. It should be pointed out that the invention is not intended to be restricted by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and / or findings from other figures and / or the present description. They show schematically:

• 1 : a motor vehicle with a first variant embodiment of a lens hood described;
• 2 : a motor vehicle with a second variant embodiment of a lens hood described;
• 3 : a described lens hood in a view from above with an image capture device;
• 4th a described lens hood in a view from below with an image capture device;
• 5 : a cross section through a section of a shielding wall with the base body of a lens hood described;
• 6th : an example of conductor structures of a described lens hood;
• 7th : a flow chart of the method described;
• 8a to 8c : the basic body or its preliminary products in various stages of manufacture; and
• 9 : a cross section through a section of the shielding wall with the base body of a lens hood described in special details.

The 1 and the 2 each show a motor vehicle 18th in which one behind the windshield 3 an image capture device 4th (for example a camera) is installed. A viewing area 6th of the image capture device 4th between the windshield 3 and the image capture device 4th is of a lens hood 1 surrounded and in particular by the lens hood 1 compared to a further interior of the motor vehicle 18th severed. The lens hood 1 has a screening wall for it 5 . The viewing area is preferred 6th but not airtight from the wider interior of the motor vehicle 3 severed. Through the lens hood 1 becomes incident scattered light 7th (laterally incident light) is not reflected and preferably adsorbed in order to prevent a negative effect on image acquisition with the image acquisition device. The lens hood 1 or the shielding wall 5 in particular has a section 8th that is at least partially opposite to the windshield 3 is trained. At least this section is preferred 8th at least partially heated. The section 8th is preferably at an angle 14th to the windshield 3 aligned, which is preferably less than 20 degrees.

In the variant according to 1 is the lens hood 1 Executed with a rounded shape that covers the viewing area 6th at least partially surrounds the circumference. This shows that the field of vision is completely surrounded by the lens hood 1 .

In the variant according to 2 the lens hood has a bottom 16 and two on the side on the floor 16 arranged side walls 17th . The field of vision 6th is located between the floor 16 and the windshield 3 as well as between the side walls 17th . Both the floor 16 as well as the side walls 17th form parts of the shielding wall 5 .

The lens hood 1 as in the 2 is shown is in the detailed views of the 3 from above and in 4th shown from below. The image capture device can be seen in each case 4th and the lens hood aligned thereon or toward the windshield, not shown, in front of it 1 .

In the 3 you can see the floor 16 from above, what a structure 15th having. In addition, they are each visible from the floor 16 on these attached side walls 17th to recognize. The image capture device is also here for better orientation 4th also drawn in, which is not part of the lens hood 1 is. In one of the side walls 17th there is a recording here (designed as an example) 20th , in which a humidity sensor 19th intervenes.

In the 4th the floor can also be seen 16 but from below with the side walls attached or attached to the side 17th . The main body can be seen here 23 that is in the section 8th is arranged or in the section 8th flat with the shielding wall 5 Here too, the receptacle is shown schematically on one of the side walls 20th shown in which the humidity sensor 19th intervenes. There is a plug on the bottom here 21 with molded. The plug 21 can through an injection mold to manufacture the lens hood 1 be given with. The connector preferably forms 21 one to the lens hood 1 attached housing in which the housing of a corresponding other connector can engage. The connector is preferred 21 made of the same material as the entire lens hood 1 (especially from the material of the shielding wall 5 ). Possibly. can the connector 21 also (partly) from the material of the base body 23 be educated.

5 shows a partial cross-section through the shielding wall 5 the lens hood in the heatable section 8th . The shielding wall can be seen 5 with the main body 23 attached to a joint 26th adjoin each other flatly. In the main body 23 are electrical conductive structures 9 integrated that a first distance 11 each other and a second distance 12th to a surface 13th the screening wall 5 exhibit. The structure is also shown 15th the screening wall 5 which is oriented towards the viewing area (not shown here). The 5 also shows that a connector 21 with contact pins 22nd that are in connection with the electrical conduction structures 9 stand on the lens hood 15th is molded on. The plug 21 can be made from the electrically conductive plastic material of the base body 23 and / or from the plastic material of the shielding wall 5 be shaped. In preferred variants, the plug is 21 formed from both materials, for example with an inner material made of the electrically conductive plastic material of the base body 23 and, moreover, with sections made of the plastic material of the shielding wall 5 , or in the form of a sheathing that forms a connector housing 29 forms.

6th shows an example of electrical conductive structures 9 that look like a comb structure 10 interlock and can thus ensure a uniform supply of current to a larger wall section.

7th is a provisional flow chart of the relevant process steps a), b), c) and d) of the manufacturing process for manufacturing the lens hoods described.

8a shows a metal part 30th for the formation of the electrical conductive structures 9 in the base body of the lens hood. It can be seen that the metal part 30th comb structures are set up for this 10 with two interlocking ridges of electrical conductive structures 9 as well as contact pin 22nd to form a stretcher. The two electrical conduction structures 9 are at separation sections 24 connected with each other. At these separation sections 24 can use the lead structures 9 separated from each other. After the separation, electrical current is required from a conductive structure 9 to the other lead structure 9 flow through the electrically conductive plastic.

In 8b it is shown that the base body 23 made of electrically conductive plastic is injected around the metal part. The base body is preferred 23 here designed so that there are still windows 25th exist through which the separating sections 24 are accessible so that the electrical conductive structures can be separated from one another. The window 25th can also serve to attach the metal part to the separating sections 24 or in the area of the separating sections 24 during the injection molding process for manufacturing the base body 23 to fix. If necessary, the windows 25th can be closed in a further processing step, for example by inserting the material of the shielding wall into the window 25th is injected after the separation of the separating sections 24 he follows.

8c shows a possible variant of the in 8b body shown 23 from the other side. This is the side that is also the interface 26th trains towards the shielding wall. It is possible that the electrical conductors 9 lie bare here and are then covered by the shielding wall (not yet shown here). If necessary, there are support beams 27 , which are molded from the electrically conductive plastic and the conductive structures 9 fix firmly.

9 shows a further embodiment variant in a cross section through the shielding wall 5 . The representation in 9 essentially corresponds to the representation in 5 , so here also refer to the explanations for 5 is referred. It can be seen that the electrical conductive structures 9 here (other than according to 5 ) are not completely enclosed by the electrically conductive plastic, but at the connection surface 26th towards the material of the shielding wall 5 issue. There are thus metallic insulation surfaces 28 on which the material of the electrical conductive structures 9 with the material of the shielding wall 5 is electrically isolated. It is also shown here that the connecting surface 26th does not have to be a flat surface, but rather it can have elevations and depressions. It is also shown here that the support beam in sections 27 Electrically conductive plastic can exist, which are the electrical conductive structures 9 on the main body 23 hold before the material of the shielding wall in the further method step (step d) of the method described 5 is applied. All the special features listed here can be transferred to possible variants of the lens hood.

List of reference symbols

1

Lens hood

2

back

3

Windshield

4th

Image capture device

5

Screening wall

6th

Viewing area

7th

Stray light

8th

section

9

electrical conduction structures

10

Comb structures

11

first distance

12th

second distance

13th

surface

14th

angle

15th

structure

16

ground

17th

Side wall

18th

Motor vehicle

19th

Humidity sensor

20th

admission

21

plug

22nd

Contact pin

23

Base body

24

Separation sections

25th

window

26th

Interface

27

Support beam

28

metallic isolation surface

29

Connector housing

30th

Metal part

Claims (9)

Lens hood (1) for an image capturing device (4) arranged on the back (2) of a windshield (3) with a shielding wall (5) which is set up for a viewing area (6) of the image capturing device (4) between the image capturing device (4) and shield the windshield (3) at least partially from incident stray light (7), characterized in that the shielding wall (5) at least in a section (8) which is oriented towards the windshield (3) on one of the viewing area (6) opposite outside of the shielding wall (5) is flatly connected to a base body (23), the base body (23) being made of an electrically conductive plastic with PTC properties, on which electrical conductive structures (9) are arranged for energizing the electrically conductive plastic . Lens hood (1) Claim 1 , wherein the base body (23) consists of at least 40 percent by weight of the electrically conductive plastic with PTC properties. Lens hood (1) according to one of the preceding claims, wherein at least two separate electrical conductive structures (9) are arranged on the base body (23). Lens hood (1) Claim 3 wherein the at least two electrical conductive structures (9) separated from one another form comb structures (10) which interlock at least in some areas. Lens hood (1) according to one of the preceding claims, wherein the shielding wall (5) is made of an electrically insulating plastic material. Lens hood (1) according to one of the preceding claims, wherein a modulus of elasticity of the material of the shielding wall (5) at room temperature is at least five times as high as a modulus of elasticity of the electrically conductive plastic with PTC properties. Lens hood (1) according to one of the preceding claims, a plug (21) being molded onto the lens hood (23), the electrical conductive structures (9) forming electrical contact pins (22) of the connector (21). Lens hood after Claim 7 , wherein the plug (21) has a plug housing (29) which is made from the material of the shielding wall (5). Lens hood after Claim 8 , wherein the electrical conductive structures (9) are arranged on a connecting surface (26) of the shielding wall (5) and the base body (23).

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