COMPOSITE PANE FOR A VEHICLE WITH INTEGRATED RADAR SENSOR

Abstract

A composite pane for a vehicle with an outer pane and an inner pane that are joined to one another via a thermoplastic intermediate layer and the composite pane is provided for separation of a vehicle interior for occupants from an external environment, wherein at least one radar sensor is integrated into the thermoplastic intermediate layer and is designed and arranged such that the radar sensor emits radar beams into the vehicle interior and receives reflected radar beams, and the radar sensor is connected to an evaluation unit for determining movement and/or presence of persons or animals in the vehicle interior.

Claims

1. A composite pane for a vehicle with an outer pane and an inner pane that are joined one another via a thermoplastic intermediate layer and the composite pane is provided for separation of a vehicle interior for occupants from an external environment, wherein at least one radar sensor is integrated into the thermoplastic intermediate layer and is designed and arranged such that the radar sensor emits radar beams into the vehicle interior and receives reflected radar beams, and the radar sensor is connected to an evaluation unit for determining movement and/or presence of persons or animals in the vehicle interior.

2. The composite pane according to claim 1 wherein the thermoplastic intermediate layer is formed from one or a plurality of thermoplastic films and the thermoplastic intermediate layer contains or is made of polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and/or polyurethane.

3. The composite pane according to claim 1, wherein the radar sensor is arranged embedded in the thermoplastic intermediate layer.

4. The composite pane according to claim 1, wherein the radar sensor is optically masked by a black print or a white print on the outer pane and/or on the inner pane.

5. The composite pane according to claim 1, wherein the radar sensor is operable for receiving radar data with a frequency bandwidth of at least 2 GHz and/or a frequency band of 76 to 150 GHz.

6. The composite pane according to claim 1, wherein the radar sensor has a detection range from 30 cm to 10 m.

7. The composite pane according to claim 1, wherein the radar sensor has a thickness of less than 1 mm.

8. The composite pane according to claim 1, wherein the radar sensor has a semiconductor chip that implements at least one radar transceiver.

9. The composite pane according to claim 8, wherein the semiconductor chip additionally implements a digital signal processing component and/or a control unit of the radar sensor, and/or the semiconductor chip and an antenna assembly of the radar sensor are implemented as a package and are integrated into the thermoplastic intermediate layer.

10. The composite pane according to claim 1, wherein the radar sensor and/or the evaluation unit is connected to onboard electronics and/or to a warning system of the vehicle or to an external output device for outputting a warning.

11. The composite pane according to claim 1, wherein the composite pane includes at least one further sensor and/or at least one further functional element.

12. A method for producing a composite pane according to claim 1 comprising: providing a stack sequence composed of an outer pane, an inner pane, and at least one thermoplastic film arranged therebetween for forming the thermoplastic intermediate layer, wherein at least one thermoplastic film includes at least one radar sensor or a radar sensor is arranged between the thermoplastic film and the outer pane and/or the inner pane, and laminating the stack sequence to form a composite pane.

13. The method for producing a composite pane according to claim 11, wherein the radar sensor is form-fittingly inserted into a cutout in at least one thermoplastic film of the thermoplastic intermediate layer.

14. The method for producing a composite pane according to claim 11, wherein the radar sensor is connected to other sensors and/or to the onboard electronics via a CAN bus.

15. A method comprising providing a vehicle for traffic on land, in the air, or on water, with a composite pane according to claim 1.

16. The composite pane according to claim 11, wherein the thermoplastic intermediate layer includes said at least one further sensor and/or at least one further functional element.

17. The method according to claim 15, wherein the composite pane is a roof panel or a windshield.

18. The method according to claim 15, wherein the vehicle is a motor vehicle.

Description

[0039] The drawings are simplified, schematic representations and are not to scale. The drawings in no way restrict the invention.

[0040] They depict

[0041] FIG. 1 a plan view of an embodiment of a composite pane according to the invention using the example of a roof panel of a vehicle,

[0042] FIG. 2 a plan view of a roof panel of FIG. 1 installed in a vehicle;

[0043] FIG. 3 a cross-sectional view of the composite pane along the section line X-X′ of FIG. 1,

[0044] FIG. 4 a flow chart of an embodiment of the method according to the invention.

[0045] Also, for the sake of simplicity, in the following reference is generally always made to only one entity. However, unless explicitly noted, the invention can also have a plurality of the entities concerned. In this respect, the use of the words “a”, “an”, and “one” is to be understood only as an indication that in a simple embodiment, at least one entity is used.

[0046] FIG. 1 depicts a plan view of an embodiment of a composite pane 100 according to the invention, using the example of a roof panel for a vehicle. Expediently, a radar sensor 4 is arranged in an approx. central position of the roof panel 100 such that it has the largest possible detection range for receiving radar data. The radar sensor(s) 4 arranged in the composite pane 100 emit(s) radar beams into the vehicle interior and receive reflected radar beams. Electrical and electronic connections of the sensors are not shown. According to the invention, the radar sensor 4 is connected to an evaluation unit (not shown) for determining movement and/or presence of persons or animals in the vehicle interior. For example, multiple radar sensors 4 can be connected to one another via a CAN bus system and can be operated simultaneously in such a CAN network. The radar data of the various sensors can then be processed and analyzed together, thus further increasing the accuracy and reliability of the resultant measurement data and the safety function. In the embodiment depicted, the radar sensor 4 is optically concealed from the vehicle interior by masking 5. The masking 5 can, for example, be a black print that can be applied in the production process, for example, at the same time as the customary masking print 6 at the perimetral edge. The application of a masking print 6 is currently common and is used primarily to mask connectors and connections in and on the composite pane 100. A black print to implement the masking 5 of the radar sensor and the masking print 6 can, for example, be applied by screen-printing on the inside surface of the inner pane III or on the outside surface IV of the inner pane 2. The masking 5 can, alternatively, be done by arranging one or a plurality of stickers. The aesthetic impression is significantly increased by the masking 5 and also by the masking print 6. In the embodiment shown, two additional radar sensors 4 are arranged in the region of the masking print 6 at the perimetral edge of the composite pane 100. This already masks the radar sensors 4 such that no additional masking 5 needs to be applied in order to obtain a visually good impression of the composite pane. Additionally, or alternatively, further masking 5 of the radar sensor 4 could be implemented on the outer pane 1 in the same way, directed toward the outside.

[0047] In one embodiment, the radar sensor 4 and/or the evaluation unit is connected to the onboard electronics and/or to a warning system of the vehicle or to an external output device for outputting a warning signal. Thus, for example, upon detection of the presence of a child by the radar sensor 4 in an otherwise unoccupied vehicle, an acoustic and/or visual signal can be outputted by the alarm system of the vehicle. A different or additional possibility would be coupling to an automatic emergency call system eCall. Thus, timely intervention can be ensured.

[0048] FIG. 2 depicts a plan view of a composite pane 100 according to the invention installed in a vehicle (car) 7 as a roof panel of FIG. 1. The description of the composite pane corresponds to that of FIG. 1. The radar sensors 4 in the region of the masking print 6 at the perimetral edge of the composite pane 100 are not shown.

[0049] FIG. 3 depicts a cross-sectional view of the composite pane 100 along the section line X-X′ of FIG. 1. The embodiment shown depicts a composite pane 100 with an outer pane 1 and an inner pane 2 and, arranged therebetween, a thermoplastic intermediate layer 3, into which a radar sensor 4 is integrated. The radar sensor 4 is arranged in a cutout of the intermediate layer 3 and is laminarly adjacent the inside surface II of the outer pane 1. The radar sensor is thus encapsulated in the intermediate layer 3 and protected against environmental influences. The formed thickness of the intermediate layer 3 is adapted to the height (thickness) of the radar sensor 4 used. Optical distortions or glass breakage during lamination to form the composite pane 100 can be largely avoided by means of the compensation of the thickness thus implemented. Masking 5, which conceals the radar sensor 4 from the vehicle interior, is arranged on the inside surface III of the inner pane 2. This enables a visually appealing appearance of the composite pane 100. The radar sensor 4 preferably has a thickness of less than 1 mm, particularly preferably of less than 0.5 mm. For example, the dimensions of the radar sensor could be 3 cm×3 cm×0.5 mm (length×width×thickness). The size in terms of the sensor area, i.e., the length and the width of the radar sensor used is, in principle, not critical, although miniaturization is always strived for, if only for aesthetic reasons.

[0050] FIG. 4 depicts a flow chart of an embodiment of the method according to the invention. Production of a composite pane 100 as described above, comprising the steps [0051] S1: Providing a stack sequence composed of an outer pane 1, an inner pane 2, and at least one thermoplastic film arranged therebetween for forming the thermoplastic intermediate layer 3, [0052] wherein at least one thermoplastic film includes at least one radar sensor 4 or a radar sensor 4 is arranged between the thermoplastic film and the outer pane 1 and/or the inner pane 2, [0053] S2: Laminating the stack sequence to form a composite pane 100.

[0054] In other words, according to the invention, in a first step S1, an outer pane 1, an inner pane 2, and the at least one thermoplastic film arranged therebetween for forming the intermediate layer 3, and the at least one radar sensor 4 are arranged and provided as a stack. The radar sensor 4 can be laminarly adjacent the outer pane 1 and/or the inner pane 2. The two panes 1 and 2 and the at least one thermoplastic film arranged therebetween are naturally arranged laminarly and essentially congruent atop one another. The radar sensor 4 is expediently positioned within the pane surfaces such that it has the desired detection range for receiving the radar data in the resulting composite pane 100 in the installed state. The radar sensors 4 according to the invention emit radar beams into the vehicle interior and receive reflected radar beams. According to the invention, the radar sensor 4 is connected to an evaluation unit (not shown) for determining movement and/or presence of persons or animals in the vehicle interior. Preferably, the radar sensor 4 is provided, prior to lamination, in step 2, for example, with a flat conductor possibly with all desired electrical or electronic connectors and contacts, for example, for connecting the radar sensor 4 to the evaluation unit and/or to the onboard electronics. The evaluation unit can, for example, integrated into the onboard electronics. Such connectors, contacts, and leads can be produced and provided in a known, customary manner, which need not be explained in detail.

[0055] The lamination and thus the joining of formed layer sequences to form the composite pane are preferably carried out under the action of heat, vacuum, and/or pressure. Methods known per se can be used to produce a composite pane. During lamination, the heated, flowable thermoplastic material flows into the spaces and around the radar sensor such that a stable bond is produced and the radar sensor is encapsulated and secured in the intermediate layer.

[0056] For example, so-called “autoclave methods” can be carried out at an elevated pressure of approx. 10 bar to 15 bar and temperatures from 130° C. to 145° C. for approx. 2 hours. Vacuum bag or vacuum ring methods known per se operate, for example, at approx. 200 mbar and 80° C. to 110° C. The outer pane, the thermoplastic intermediate layer, and the inner pane can also be pressed in a calender between at least one pair of rollers to form a pane. Systems of this type are known for the production of panes and usually have at least one heating tunnel upstream of a pressing unit. The temperature during the pressing operation is, for example, from 40° C. to 150° C. Combinations of calendering and autoclaving methods have proved particularly effective in practice. Alternatively, vacuum laminators can be used. These consist of one or a plurality of heatable, evacuable chambers, in which the panes are laminated within, for example, approx. 60 minutes at reduced pressures of 0.01 mbar to 800 mbar and temperatures of 80° C. to 170° C.

[0057] According to the invention, a composite pane is made available, with which the safety of occupants in in a vehicle can be further increased. In particular, even with environmental conditions unfavorable for other, optical systems, such as darkness or high heat and intense sunlight, reliable measurement and evaluation of data concerning movement and/or presence of persons or animals, are provided in a vehicle interior by the solution according to the invention with the integrated radar sensor. For example, children or animals left behind in an otherwise abandoned vehicle can be detected and a timely intervention can be made possible. Moreover, driver monitoring can also be further improved and reliably provided.

[0058] The production of a composite pane according to the invention with an integrated radar sensor can be carried out simply and economically and is suitable even for series production.

LIST OF REFERENCE CHARACTERS

[0059] 100 composite pane [0060] 1 outer pane [0061] 2 inner pane [0062] 3 intermediate layer [0063] 4 radar sensor [0064] 5 masking [0065] 6 masking print [0066] 7 vehicle [0067] I outside surface of the outer pane [0068] II inside surface of the outer pane [0069] III inside surface of the inner pane [0070] IV outside surface of the inner pane