Vehicle roof with ambient sensor and cooling system

Abstract

Vehicle roof, in particular for a passenger car, comprising a one- or multi-part roof skin (18, 18'), at least one environment sensor (22, 24, 26) for detecting a vehicle environment, which is arranged under the roof skin (18, 18') and can detect the vehicle environment via a sensor viewing area (44) of the roof skin (18, 18'), and a cooling device (46, 46') for cooling the environment sensor (22, 24, 26), wherein the cooling device (46, 46') is at least partially arranged in a wet area and the environment sensor (22, 24, 26) is arranged in the wet area.

Description

[0001] The invention relates to a vehicle roof, in particular a vehicle roof for a passenger car, comprising an environmental sensor for detecting a vehicle environment, which is arranged under a roof skin, and a cooling device for cooling the environmental sensor.

[0002] Such a roof is known in practice and can be designed as a roof module that can be attached as a separate structural unit to a passenger car body forming a vehicle shell. As an interface to the vehicle roof, the vehicle body comprises roof beams, which can be designed as longitudinal beams and / or transverse beams and represent a support structure on the vehicle shell. The vehicle roof comprises a roof skin that forms an outer visible surface and has sensor viewing areas through which environmental sensors, which serve to detect the vehicle's surroundings and are arranged under the roof skin, can detect the vehicle's surroundings.

[0003] Autonomous or semi-autonomous vehicles, for example, comprise a roof designed as a sensor roof module or Roof Sensor Module (RSM), which is equipped with a large number of environmental sensors. The environmental sensors, which are integrated in a dry area into the vehicle roof, which is particularly designed as a roof module, and which are designed as lidar sensors and / or radar sensors and / or cameras, for example, record the environment around the vehicle and provide the corresponding measurement signals to the control electronics of the vehicle in question so that a respective traffic situation can be determined and the driving behavior of the vehicle in question can be adapted to this traffic situation. To ensure continuous availability of the environmental sensors, they must, among other things, be kept within a specific temperature window, for which purpose a thermal device designed as a cooling device is used.The cooling system includes, for example, heat pipes connected to the environmental sensors located in the dry area. The separation of the vehicle roof into dry and wet areas places high demands on the sealing system to be integrated. The construction of cooling systems, which were previously used to cool the environmental sensors on vehicle roofs, is therefore complex.

[0004] From the publication DE 10 2019 124 362 A1, a vehicle roof is known that includes environmental sensors and a cooling system. The environmental sensors and the cooling system are arranged beneath a cover forming an outer roof skin, protected from water.

[0005] From the document DE 10 2019 105 339 A1, a roof module for autonomous vehicles is known which comprises environmental sensors arranged in a housing.

[0006] Document DE 10 2020 102 874 A1 describes a roof module for a motor vehicle comprising a sensor system with environmental sensors arranged in a protected manner beneath a roof skin. Also arranged beneath the roof skin is an air conditioning unit that can maintain the environmental sensors at a desired operating temperature via a thermal duct arrangement.

[0007] The invention is based on the object of creating a vehicle roof in which at least one environmental sensor and the cooling device for the environmental sensor are designed in an optimized manner.

[0008] This object is achieved according to the invention by the vehicle roof having the features of patent claim 1.

[0009] According to the invention, a vehicle roof, in particular a vehicle roof for a passenger car, is proposed, comprising a single- or multi-part roof skin, at least one environmental sensor for detecting the vehicle's surroundings, which is arranged beneath the roof skin and can detect the vehicle's surroundings via a sensor-transparent area of ​​the roof skin, and a cooling device for cooling the environmental sensor. The cooling device is arranged at least partially in a wet area. The environmental sensor is also arranged in the wet area.

[0010] In the vehicle roof according to the invention, the environment sensor is therefore arranged in a wet area into which water can penetrate from the outside. Since the environment sensor is arranged below the roof skin, which represents a covering, accumulated heat can build up in the area of ​​the environment sensor due to sensor operation and / or external heat effects. Therefore, the cooling device is also arranged at least partially in the wet area, by means of which air can be sucked in, in particular via an inlet in the roof skin, which can be used to cool the environment sensor and then blown out again via an outlet provided, in particular, in the roof skin. In this way, it can be achieved in a structurally simple manner that the operating temperature of the environment sensor is kept below a critical limit temperature, which is, for example, 85 °C, or that the temperature of the environment sensor is brought below this limit temperature in a short time.Heat buildup caused by ambient temperature, solar radiation, or waste heat from the environmental sensor can be effectively dissipated. This improves uninterrupted sensor availability.

[0011] The environment sensor of the vehicle roof according to the invention can be designed in a variety of ways, use electromagnetic radiation and / or acoustic waves and, for example, comprise a lidar sensor, a radar sensor, an optical sensor such as a camera, an antenna device and / or the like.

[0012] If the environment sensor is a lidar sensor, it preferably operates in a wavelength range of approximately 905 nm or approximately 1550 nm. A camera used as an environment sensor can operate in the wavelength range of visible light and / or in the infrared range.

[0013] The roof skin of the vehicle roof according to the invention is formed in one or more parts and at least partially overlaps the environment sensor, which can be part of a sensor module. Furthermore, the roof skin comprises a sensor see-through area, which is particularly window-like and transparent to the wavelength range used by the environment sensor. The sensor see-through area can be closed and then form a one-piece component of the roof skin or an insert thereof. The sensor see-through area can also represent a recess into which the environment sensor engages with a housing or the like. In this case, the environment sensor itself forms an externally visible part of the roof skin, which lies within the roof skin recess.

[0014] The sensor's visible area is particularly transparent for a wavelength range between 300 nm and 2000 nm. It is also advantageous if the sensor's visible area is permeable to radar beams.

[0015] To achieve effective air circulation, a preferred embodiment of the vehicle roof according to the invention is designed such that the cooling device comprises at least one air duct in which a fan is arranged. The fan draws in fresh cooling air and expels it again, in particular via the inlet formed in the roof skin and the outlet formed in the roof skin. The air duct is assigned to the wet area of ​​the vehicle roof. The fan, which is arranged in the air duct, is thus also assigned to the wet area.

[0016] In a special embodiment of the vehicle roof according to the invention, a heat sink is arranged in the air duct. This heat sink is exposed to an air flow in the air duct and is connected to a base of the ambient sensor via at least one thermal conductor, which can be designed as a so-called heat pipe. The thermal conductor can be arranged in a dry area of ​​the vehicle roof that is sealed off from the wet area. The base of the ambient sensor borders this dry area.

[0017] For example, the base of the environmental sensor is inserted into a cutout of a support structure spanned by the roof skin and preferably formed by a roof frame. The thermal cable can be effectively connected to the environmental sensor located in the wet area via the cutout. The environmental sensor is mounted directly or indirectly via a holder on the support structure, preferably in such a way that a circumferential seal is arranged on the base of the environmental sensor, which interacts with the support structure and encompasses the cutout.

[0018] The base of the environmental sensor can be formed by the holder, which forms a closed shell or a carrier plate and is attached, in particular, to the support device from above. This allows the environmental sensor to be mounted from the outside, i.e., completely in the wet area. Thermally conductive paste can be applied between the holder and the environmental sensor.

[0019] If the environmental sensor is mounted on the support device without a holder, a flat rubber mat or similar device can be provided between the environmental sensor and the support device for sealing. The rubber mat must have recesses for at least one thermal cable.

[0020] In another special embodiment of the vehicle roof according to the invention, air-guiding ribs can be formed on the inside of the roof skin to form the air duct. These ribs can be manufactured in one piece with the roof skin, which is particularly made of plastic. This represents a cost-effective, robust design that is also easy to install and replace. Only a few components are required while maintaining high cooling efficiency.

[0021] To eliminate the need for additional components for air guidance, the ambient sensor can be located in the air duct formed by the air guidance fins. The ambient sensor is thus directly surrounded and cooled by the air flowing through the air duct.

[0022] To keep the environment sensor as easily accessible as possible for installation or maintenance purposes, the roof skin can include at least one removable dome, beneath which the environment sensor is located and which, in particular, also encompasses the sensor viewing area. The dome, which is particularly removable, can be latched and / or glued and / or screwed to adjacent areas of the roof skin. A fan of the cooling system can also be arranged beneath the dome and thus located in the wet area together with the environment sensor. The purely wet-room-side cooling solution eliminates the need for sealing interfaces towards the vehicle interior.

[0023] A preferred embodiment of the roof according to the invention is designed as a roof module. Such a roof module forms an integrated structural unit that accommodates components required for autonomous or semi-autonomous driving of the vehicle in question. The roof module, which can thus integrate a multitude of functional elements, thus represents a compact structural unit that is connected by a vehicle manufacturer to a vehicle body or a vehicle shell that includes roof spars, such as roof side spars and / or longitudinal roof spars. The vehicle roof designed as a roof module thus represents a sensor roof module or roof sensor module (RSM), which enables autonomous or semi-autonomous driving of the vehicle in question.

[0024] A vehicle equipped with the vehicle roof according to the invention and designed as an autonomous vehicle drives independently in the autonomous driving mode, at least without significant intervention by a driver. In a semi-autonomous driving mode, the vehicle roof according to the invention forms, for example, part of a driver assistance system.

[0025] The vehicle roof according to the invention can be provided with a transparent fixed roof section and / or a roof opening system for a roof opening.

[0026] In particular, the vehicle roof according to the invention is the roof of a passenger car. However, it can also be the roof of a commercial vehicle, which could be designed, for example, as a delivery van, a bus, an autonomously driving minibus, such as a so-called people mover, or even a truck tractor.

[0027] The invention also relates to a motor vehicle which comprises a vehicle roof of the type described above and in which, in particular, a vehicle body shell can be provided with a roof module which is designed as a sensor roof module or roof sensor module.

[0028] Further advantages and advantageous embodiments of the subject matter of the invention can be found in the description, the drawings and the patent claims.

[0029] Exemplary embodiments of a motor vehicle with a vehicle roof according to the invention are shown schematically in simplified form in the drawing and are explained in more detail in the following description. It shows: Fig. 1 is a perspective top view of a motor vehicle with a roof module according to the invention; Fig. 2 a second perspective top view of the vehicle with the roof module; Fig. 3 a Fig. 2 corresponding view, but with the roof skin element removed; Fig. 4 a perspective bottom view of the roof module; Fig. 5 a perspective sectional view of the roof module along the line VV in Fig. 3; Fig. 6 a second perspective sectional view along the line VV in Fig. 3; Fig. 7 a perspective bottom view of the roof module in the area VII in Fig. 4; Fig. 8 a bottom view of the roof module in the area of ​​an environmental sensor; Fig. 9 a plan view of the roof module in the area of ​​an environmental sensor; Fig. 10 a perspective bottom view of the environment sensor with a holder in a standalone position; Fig. 11 a perspective view of the holder in isolation; Fig. 12 is a perspective top view of a motor vehicle with an alternative embodiment of a roof module according to the invention; Fig. 13 a perspective top view of the roof module according to Fig. 12 in unique position; Fig. 14 a perspective view of a dome of a roof skin of the roof module according to Fig. 12; Fig. 15 a Fig. 14 corresponding representation of the cathedral, but in a partially transparent representation; Fig. 16 a perspective bottom view of the dome together with a sensor module and a fan; and Fig. 17 a perspective view of the cathedral in isolation.

[0030] In Fig. 1 shows a motor vehicle 10 designed as a passenger car and provided with a vehicle roof 12, which comprises a roof side member 14 on each side relative to a vertical longitudinal center plane of the vehicle, which is part of a vehicle body representing a shell. Between the roof side members 14, the vehicle roof 12 comprises a roof module 16, which forms a structural unit and is firmly connected to the roof side members 14 forming a shell support structure.

[0031] The roof module 16, which is located in the Fig. 2 to 10, comprises a multi-part roof skin 18 which is fastened to a surrounding roof frame 20, which represents a support device of the roof module 16 and forms an interface thereof to the vehicle body.

[0032] The roof module 16 is designed as a sensor roof module or roof sensor module (RSM) equipped with devices that enable autonomous driving of the motor vehicle 10. For this purpose, the roof module 16 has a sensor system that includes, in a front-end section relative to the vehicle's longitudinal center plane, two lateral environmental sensors 22 and 24 and a centrally arranged environmental sensor 26. The environmental sensors 22, 24, and 26 can be used to detect the vehicle's surroundings to realize autonomous driving of the motor vehicle 10. By evaluating the measurement signals from the environmental sensors 22, 24, and 26 using a control device of the motor vehicle 10, a respective traffic situation can be determined, so that the motor vehicle 10 can adapt autonomously or independently to the respective traffic situation and behave accordingly.

[0033] The environmental sensors 22, 24 and 26 can be designed in a variety of ways and, for example, each comprise a lidar sensor, a radar sensor, a camera and / or another suitable sensor.

[0034] As shown in the drawing with reference to the environment sensor 24, the environment sensors 22, 24, and 26 are each arranged on a plate-like holder 28, which is provided on its underside with a circumferential seal 30 arranged in a groove, via which the respective holder 28 rests on the roof frame 20. The seal 30 encloses a corresponding cutout 32 in the roof frame 20.

[0035] The environmental sensors 22, 24, and 26 are each connected from below to the respective plate-shaped holder 28 via screw connections 34. The holders 28 are in turn connected from above to the roof frame 20 via screw connections 36, with the optionally provided screw tabs of the holders 28 being additionally sealed to the roof frame 20. If, in an alternative embodiment, the holder can be screwed to the roof frame from below in a manner not shown, it is possible to arrange the screw tabs of the holder within the circumferential seal of the holder to the roof frame. Screw seals can then be omitted if necessary.

[0036] The roof skin 18 comprises domes 38, 40, and 42, beneath each of which one of the environment sensors 22, 24, and 26 is arranged. The domes 38, 40, and 42 are removable for maintenance and assembly purposes and each include a window-like sensor viewing area 44 through which the respective environment sensor 22, 24, or 26 can detect an area of ​​the vehicle's surroundings.

[0037] In order to cool the environmental sensors 22, 24, and 26 and thus maintain them at a desired operating temperature, a cooling device 46 is provided, which comprises an air duct 48 in the form of pipes 50 beneath the roof frame 20 between an inlet 52, which is arranged beneath the dome 40, and an outlet 54, which is arranged beneath the dome 38. In order to be able to draw in air, the dome 40 is provided with air inlet slots 56 or air inlet openings. In order to be able to blow out air, the dome 38 is provided with air outlet slots 58 or air outlet openings. Fans 60, which convey the air through the pipes 50, are arranged in the pipes 50.Furthermore, heat sinks 62 are arranged in the tubes 50 forming the air duct 48, which are cooled by the sucked-in air and which are connected via thermal lines 64, which are designed as so-called heat pipes, to cooling plates 66, each representing a heat pipe connection, which are arranged on the undersides of the holders 28 of the environmental sensors 22, 24 and 26.

[0038] The inlet 52 and the outlet 54 of the air duct 48, which is part of the cooling device 46, are located together with the environmental sensors 22 and 24 in the wet area into which moisture from the vehicle environment can penetrate, whereas the thermocouple lines 64, which extend between the heat sinks 62 and the cooling plates 66 of the holders 28 for the environmental sensors 22, 24 and 26, are located in the dry area of ​​the vehicle roof 12, which is sealed off from the wet area.

[0039] In the Fig. 12 to 17, a roof module 16' is shown, which represents an alternative embodiment and is also a component of a vehicle roof 12 of a motor vehicle 10. According to the embodiment according to the Fig. 1 to 11, the roof module 16' comprises a multi-part roof skin 18', which, in a bow-side section relative to the vertical longitudinal center plane of the vehicle, is provided with two lateral domes 38' and 40' and a centrally arranged dome 42', each of which is designed as an attachment part of the otherwise continuous roof skin 18. The domes 38', 40', and 42' each also comprise a sensor viewing area 44 for an environment sensor 22, 24, or 26, respectively, which is arranged beneath the respective dome 38', 40', or 42'.

[0040] To form a cooling device 46', the domes 38', 40', and 42' each comprise an air inlet formed by slots 56 and an air outlet formed by slots 58. On the underside or inside of the plastic domes 38', 40', and 42', air guide ribs 70 are formed in one piece, forming an air channel 48' in which the respective environmental sensor 22, 24, or 26 is arranged. Air drawn in through the air inlet slots 56 can thus flow around the respective environmental sensor 22, 24, or 26, cool it, and then flow out again through the air outlet slots 58. A fan 60 is arranged beneath each of the domes 38', 40', and 42' to draw in and expel the air. List of reference symbols 10 motor vehicle 12 Vehicle roof 14 Roof side rail 16, 16' roof module 18, 18' roof skin 20 roof frames 22 Environment sensor 24 Environment sensor 26 Environment sensor 28 holders 30 Seal 32 Excerpt 34 screw connection 36 screw connection 38, 38' Cathedral 40, 40' Cathedral 42, 42' Cathedral 44 Sensor viewing area 46, 46' cooling device 48, 48' air duct 50 pipes 52 Entrance 54 Outlet 56 air intake slots 58 air outlet slots 60 fans 62 heat sinks 64 thermocouple cables 66 Cooling plate 70 air guide ribs

Claims

[1] Vehicle roof, in particular for a passenger car, comprising a single-part or multi-part roof skin (18, 18'), at least one environmental sensor (22, 24, 26) for detecting a vehicle's surroundings, which is arranged under the roof skin (18, 18') and can detect the vehicle's surroundings via a sensor viewing area (44) of the roof skin (18, 18'), and a cooling device (46, 46') for cooling the environmental sensor (22, 24, 26), wherein the cooling device (46, 46') is arranged at least partially in a wet area and the environmental sensor (22, 24, 26) is arranged in the wet area. [2] Vehicle roof according to claim 1, characterized by that the cooling device (46, 46') comprises at least one air duct (48, 48') in which a fan (60) is arranged. [3] Vehicle roof according to claim 1 or 2, characterized bythat a heat sink (62) is arranged in the air duct (48) and is connected to a base of the environment sensor (22, 24, 26) via at least one thermal line (64). [4] Vehicle roof according to claim 3, characterized by that the base of the environment sensor (22, 24, 26) is inserted into a cutout (32) of a support device which is spanned by the roof skin (18) and which is preferably formed by a roof frame (20). [5] Vehicle roof according to claim 4, characterized by that a circumferential seal (30) is arranged on the base of the environment sensor (22, 24, 26), which seal cooperates with the carrier device and surrounds the cutout (32). [6] Vehicle roof according to claim 4 or 5, characterized by that the base of the environment sensor (22, 24, 26) is a holder (28) which is fastened in particular from above to the carrier device. [7] Vehicle roof according to one of claims 1 to 6, characterized bythat the roof skin (18, 18') comprises at least one air inlet opening and at least one air outlet opening so that air can flow through the cooling device (46, 46'). [8] Vehicle roof according to one of claims 1 to 7, characterized by that air guide ribs (70) are formed on an inner side of the roof skin (18), which form an air duct (48') of the cooling device (46'). [9] Vehicle roof according to claim 8, characterized by that the environment sensor (22, 24, 26) is located in the air duct (48') formed by the air guide ribs (70). [10] Vehicle roof according to one of claims 1 to 9, characterized by that the roof skin (18, 18') comprises at least one removable dome (38, 38', 40, 40', 42, 42') under which the environment sensor (22, 24, 26) is arranged. [11] Vehicle roof according to one of claims 1 to 10, characterized by that it is a roof module (16, 16'). [12] Motor vehicle comprising a vehicle roof according to one of claims 1 to 11.

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