CN115004078A

CN115004078A - Camera module

Info

Publication number: CN115004078A
Application number: CN202080094210.5A
Authority: CN
Inventors: A·莫尔勒; J·恩格尔哈特; G·B·芬纳赫; P·狄塞耳
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2020-01-22
Filing date: 2020-12-02
Publication date: 2022-09-02
Also published as: WO2021148179A1; KR20220126769A; DE102020200695A1

Abstract

The invention relates to a camera module comprising a lens (14), a lens barrel (18) by means of which the lens (14) is held, and a heating element (30) which lies against the lens (14) and by means of which the lens (14) can be heated. The lens barrel (18) is made of a metallic material, and an insulating means (34) is arranged between the heating element (30) and the lens barrel (18), by means of which the heating element (30) is insulated from the lens barrel (18).

Description

Camera module

Technical Field

The invention relates to a camera module for a motor vehicle, comprising a lens, a lens barrel, and a heating element, by means of which the lens is held; the heating element rests against the lens and can heat the lens via the heating element. Furthermore, the invention relates to a camera assembly comprising such a camera module.

Background

Camera systems are used in many fields. Such camera systems are used, for example, in motor vehicles as optical camera systems for sensing information. In this case, the camera system senses the vehicle environment and provides information to other vehicle systems, for example.

In order to sense information of the vehicle environment, the lens of the camera must be subjected to the surrounding environment. Whereby the lens may also be wet in wet weather. In winter, it is also possible that the lens has an ice layer due to low temperatures. If the lens is wet or has an ice layer, the image sensor does not obtain a signal or only obtains a poor signal. In order to remove moisture or ice layers from the lens, a lens heating device is usually provided, with which the lens can be heated. Whereby the moisture on the lens can be evaporated and the ice layer removed. Thus, the image sensor can also acquire signals that can be evaluated analytically in such weather.

WO 2019/095488 a1 discloses a camera module with a heating function. The camera module includes a lens barrel, a first lens at a front end of the lens barrel, and a heating device capable of heating the first lens. By providing a heating means, the exposed first lens can be heated such that the camera module remains operational in cold, humid and other weather conditions.

A sealing arrangement for the static sealing of optical components at risk of freezing is known from the subsequently published prior art DE 102019207691 a 1. The sealing assembly itself is used here as a heat source in order to heat optical components, such as lenses, which are at risk of freezing.

Disclosure of Invention

The object on which the invention is based is to specify a camera module which has a better image quality under the conditions of use of the camera module.

This object is achieved by a camera module for a vehicle according to the preamble of claim 1 in combination with the features of the characterizing portion of claim 1. The following dependent claims reflect advantageous developments of the invention. A camera assembly with a camera module according to the invention is given in claim 10.

The present invention comprises the following technical teaching: the lens barrel is composed of a metal material, and an insulating device, by which the heating element is insulated from the lens barrel, is disposed between the heating element and the lens barrel.

Here, the lens barrel made of metal has an advantage that it can be manufactured more precisely than an injection molding material. Thereby, manufacturing tolerances of such a lens barrel can be reduced. In case the lens is subsequently aligned with the image sensor, a better image can thus be achieved. The production is thereby also simplified and the camera module can therefore be produced more economically.

In the case of metallic materials, the thermal expansion is smaller compared to plastic materials, so that the calibrated distance of the lens to the image sensor remains substantially the same over the application temperature range. Improved image quality can thus also be achieved permanently.

In addition to the above-mentioned properties, the camera module also has a heating element, so that good images can be produced also in different weather conditions. The heating element can be electrically and thermally insulated with respect to the lens barrel composed of metal by an insulating means. Thus, no thermal or electrical problems occur despite the use of a heating element having a barrel composed of metal. In addition to the electrical and thermal insulation properties, the insulating means also have a sealing action, so that the interior space can be protected from water or salts, whereby the image quality also remains unchanged during the service life.

In a preferred embodiment of the invention, the insulating means is formed by a lens having an area arranged between the lens barrel and the heating element. Accordingly, the lens is arranged between the lens barrel and the heating element. Therefore, the lens is heated first. Thus, the lens has electrical and thermal insulating effects. This has the advantage that no further material has to be provided for the insulation.

In a further preferred embodiment of the invention, the insulating means has a film, adhesive tape or lacquer and is arranged between the lens barrel and the heating element. These devices can be applied simply and with targeted precision. This makes it possible to insulate the desired region. The insulating means can be applied not only to the heating element itself, but also to the corresponding region on the lens barrel or to both.

Preferably, the lens barrel is composed of an aluminum material. The advantage of aluminum materials compared to other metals is that they are lightweight and still have sufficient strength. Thereby, the weight of the camera module can be kept low despite the use of the metal material.

In an advantageous embodiment, the insulating means has an anodized layer which is formed on the lens barrel at least in the region between the lens barrel and the heating element. Since the lens barrel is made of aluminum, an anodized layer can be applied to the aluminum by an anodizing method. The anodized layer is electrically non-conductive so that the heating element is electrically insulated with respect to the lens barrel. The insulating layer is applied in a simple and economical manner by means of anodic oxidation.

Anodic oxidation has the additional advantage of: no additional components are required for producing the electrical insulation, so that the number of components required can be reduced.

The insulating device advantageously has an injection-molded part which is injection-molded onto the heating element. The injection-molded part has the following advantages: it can be constructed simply in any shape. Furthermore, plastics are inexpensive and can be processed economically. The plastic material has a low weight, so that the overall weight of the camera module is not increased significantly. Furthermore, plastics have a large selection range, so that plastics with good insulating properties can be selected.

In a further advantageous embodiment, the injection-molded insulating component has at least one sealing lip, by means of which the interior space of the lens barrel is sealed off from the outside of the camera module. The sealing lip is preferably designed as a bead. Thereby, in addition to the insulating effect, a sealing effect can be achieved, so that necessary seals, such as O-rings, can be dispensed with. Thereby reducing the number of necessary components. Furthermore, such a sealing lip can be easily constructed by injection molding.

The at least one sealing lip is preferably arranged radially and/or axially on the heating element. The radial and axial directions relate to the optical axis of the camera module. The inner space is protected against the ingress of moisture, dirt or salts by a radially oriented sealing lip. The advantage of a sealing lip oriented in the axial direction is that the sealing lip can be compressed during the axial assembly of the lens. This results in an assembly gap, so that manufacturing tolerances can be compensated better and the definition of the camera module can be adjusted more easily. The image quality of the camera module can be improved by such a sealing lip, which also protects against moisture and dirt.

According to one advantageous embodiment, the heating element comprising electrically conductive plastic and the insulating means are configured as a two-component injection-molded component. Accordingly, both the heating element and the insulating means are composed of plastic material, which is formed together in a two-component injection molding process. In the two-component injection molding method, a first component is first formed, which comprises a first material. The second component is then formed from a second material.

Thus, the two components can be manufactured together in an injection molding process. The heating element and the insulating means can thus be constructed in a simple and economical manner. Furthermore, the connection between the heating element and the insulating means is improved by means of an injection moulding method.

Drawings

Embodiments of the invention are illustrated in the drawings and set forth in greater detail in the following description. The figures show:

figure 1 is a sectional view of a camera module according to a first embodiment,

figure 2a is a view of a heating element with an insulating device,

FIG. 2b is a view of a heating element with another embodiment of an insulating device, an

FIG. 3 is a cross-sectional view of an embodiment of a lens having a heating element.

Detailed Description

Fig. 1 shows a sectional view of a camera module according to a first exemplary embodiment. The camera module here comprises a lens 14 which is subjected to the external ambient environment of the camera module. The lens 14 is held in a barrel 18. In this embodiment, the lens barrel 18 is composed of an aluminum material. For axial fixing of the lens 14, a retaining nut 22 is arranged on the edge side against which the lens 14 bears. The lock nut 22 is connected to a radial region of the lens barrel 18 by a screw thread (not shown).

The barrel 18 forms a radial widening in the fixing area of the lens 14, so that a flange 26 is formed. The heating element 30 is disposed between the flange 26 and the lens 14. In this exemplary embodiment, the heating element 30 is of annular design. The lens 14 is heated by the heating element 30 in direct contact with the lens 14 so that moisture or ice on the lens 14 can be removed. The heating element 30 is made of electrically conductive plastic. In order to electrically and thermally insulate the heating element 30 from the lens barrel 18 made of aluminum, an insulation device 34 is arranged between the lens barrel 18 and the heating element 30. In this embodiment, the insulating device 34 is implemented as a film.

Above the heating element 30, an O-ring 38 is arranged, by means of which the inner space 42 is sealed off from external influences, such as water, salt, etc., except for the insulating means 34. Here, an O-ring 38 is disposed between the lens 14 and the barrel 18.

Fig. 2a shows a view of the heating element 30 with the insulation means 34. The insulating means 34 differs from the insulating means 34 shown in fig. 1 in that the insulating means 34 is constructed from a plastic material which is injection-molded onto the heating element 30. The heating element 30 and the insulating means 34 are designed as a two-component injection molded part. Furthermore, the insulating means 34 has a radially acting sealing lip 46 above the heating element 30. In the mounted state, the sealing lip 46 is arranged here between the lens barrel 18 and the lens 14. The sealing lip 46 thus assumes the same function as the O-ring 38 shown in fig. 1, and accordingly, such an O-ring 38 can be eliminated.

In fig. 2b a view of a heating element 30 with another embodiment of an insulating means 34 is shown. This insulating component 34 differs from the insulating component 34 shown in fig. 2a in that an axially acting sealing lip 46 is arranged below the heating element 30. In this case, the sealing lip 46 bears axially against the barrel 18. In addition to the sealing function, the sealing lip 46 can also compensate axial assembly tolerances due to compressibility.

Fig. 3 shows a cross-sectional view of an embodiment of the lens 14 with a heating element 30. This embodiment differs from the embodiment shown in fig. 1 in that the heating element 30 does not abut directly against the lens barrel 18. In this embodiment, the lens 14 is formed by an outer lens 14a and an inner lens 14b abutting each other on a flat side. The outer lens 14a and the inner lens 14b together form a recess 50 in which the heating element 30 is received. Therefore, the heating element 30 does not have to be applied to the lens barrel 18. The insulating device 34 is formed accordingly by the lens 14. No additional insulating device 34 is required.

Claims

1. A camera module comprising a lens (14), a lens barrel (18) by means of which the lens (14) is held, and a heating element (30) which lies against the lens (14) and by means of which the lens (14) can be heated

It is characterized in that the preparation method is characterized in that,

the lens barrel (18) is made of a metallic material, and an insulating means (34) is arranged between the heating element (30) and the lens barrel (18), by means of which the heating element (30) is insulated from the lens barrel (18).

2. Camera module according to claim 1, characterized in that the insulating means (34) is formed by the lens (14) having a region arranged between the lens barrel (18) and the heating element (30).

3. Camera module according to claim 1, characterized in that the insulating means (34) comprises a film, adhesive tape or lacquer and is arranged between the lens barrel (18) and the heating element (30).

4. A camera module according to claim 1 or 3, characterized in that the lens barrel (18) consists of an aluminum material.

5. The camera module according to claim 4, characterized in that the insulating means (34) has an anodized layer which is formed on the lens barrel (18) at least in the region between the lens barrel (18) and the heating element (30).

6. Camera module according to one of the preceding claims, characterized in that the insulating means (34) has an injection-molded part which is injection-molded onto the heating element (30).

7. The camera module according to claim 6, characterized in that the injection-molded insulating means (34) has at least one sealing lip (46) by means of which the interior space (42) of the lens barrel (18) is sealed off from the outside of the camera module.

8. The camera module according to claim 7, characterized in that the at least one sealing lip (46) is arranged radially and/or axially on the heating element (30).

9. Camera module according to one of the preceding claims, characterized in that the heating element (30) comprising electrically conductive plastic and the insulating means (34) are configured as two-component injection-molded components.

10. A camera assembly comprising a camera module according to any one of the preceding claims.