COOLING DEVICE FOR AN OBJECT DETECTION SENSOR

Abstract

A cooling device for an object detection sensor, having a sensor-side heat transmission element, a sensor-distant heat absorption element, wherein the sensor-side heat transmission element and the sensor-distant heat absorption element are arranged opposite to one another, wherein a heat transmission surface of the sensor-distant heat transmission element and a heat absorption surface of the sensor-distant heat absorption element are designed to be spaced apart from one another by an intermediate space. Furthermore, an object detection sensor including such a cooling device is described.

Claims

1. A cooling device for an object detection sensor, comprising a sensor-side heat transmission element a sensor-distant heat absorption element wherein the sensor-side heat transmission element and the sensor-distant heat absorption element are arranged opposite to one another, wherein a heat transmission surface of the sensor-side heat transmission element and a heat absorption surface of the sensor-distant heat absorption element are designed to be spaced apart from one another by an intermediate space, wherein the cooling device is designed to provide a relative movement between the heat transmission element and the heat absorption element, wherein the relative movement is a pivoting movement.

2. The cooling device according to claim 1, wherein the heat transmission element is formed by sensor housing of the object detection sensor or is connected to a sensor housing of the object detection sensor.

3. The cooling device according to claim 1, wherein the heat absorption element is formed by a holding element or is connected to a holding element.

4. (canceled)

5. The cooling device according to claim 1, wherein the heat transmission element and the heat absorption element have a distance to one another at each relative position so that there is no abutting contact between them.

6. The cooling device according to claim 1, wherein the heat transmission element and/or the heat absorption element have/has ribs.

7. The cooling device according to claim 1, wherein the ribs of the heat transmission element and the ribs of the opposite heat absorption element engage with one another.

8. The cooling device according to claim 1, wherein between two adjacent ribs of the heat transmission element or heat absorption element, a free space is formed in which a rib of the opposite heat absorption element or heat transmission element engages.

9. The cooling device according to claim 1, wherein the heat transmission element is in abutting contact with a circuit board and/or a chip of the object detection sensor.

10. The cooling device according to claim 1, wherein the heat transmission surface has a surface optimized for emission and/or the sensor-distant heat transmission surface has a surface optimized for absorption.

11. An object detection sensor comprising a cooling device for an object detection sensor, said cooling device comprising: a sensor-side heat transmission element; and a sensor-distant heat absorption element; wherein the sensor-side heat transmission element and the sensor-distant heat absorption element are arranged opposite to one another, wherein a heat transmission surface of the sensor-side heat transmission element and a heat absorption surface of the sensor-distant heat absorption element are designed to be spaced apart from one another by an intermediate space; and wherein the cooling device is designed to provide a relative movement between the heat transmission element and the heat absorption element, wherein the relative movement is a pivoting movement.

Description

[0049] In the figures:

[0050] FIG. 1 shows a perspective view of an object detection sensor with a cooling device;

[0051] FIG. 2 shows a cross-sectional view of the object detection sensor with the cooling device of FIG. 1;

[0052] FIG. 3 shows a partial perspective view of a holding element of the object detection sensor with the cooling device from FIG. 1;

[0053] FIG. 4 shows the holding element from FIG. 3 in a front view.

[0054] FIG. 1 illustrates an object detection sensor 10 having a cooling device 12. The object detection sensor 10 comprises a multi-part housing 14 with the sensor components and a holding element 16 on which the multi-part housing 14 is arranged. In this case, the object detection sensor 10 is designed as a LIDAR system, which has a transmitting element 18 in the form of a transmitting chip, a receiving element 20 in the form of a receiving chip, and a main circuit board with further electronic components. Main circuit board 22. In addition, the object detection sensor 10 has an optical transmitting system 24 and an optical receiving system 26, each of which has an optics housing for arranging a plurality of optical elements. Optical transmitting system 24 and optical receiving system are shown in FIG. 2 only schematically and without further detail. The LIDAR system is designed particularly advantageously according to the LIDAR system published in patent specification WO 2017/081294 A1.

[0055] The multi-part housing 14 of the object detection sensor 10 is arranged to be pivotable relative to the holding element 16 via bearing elements 28. By pivoting, for example, a viewing area of the object detection sensor 10 can be aligned with a horizon to optimally adapt the field of vision to the environment.

[0056] During operation of the object detection sensor 10, the electronic components, in particular the transmitting element 18 and the receiving element 20, generate heat energy. This heat energy is dissipated from the object detection sensor via the cooling device 12.

[0057] The cooling device 12 comprises a heat transmission element 30 formed on the sensor side and a heat absorption element 32 formed distant from the sensor. The heat transmission element 30 is formed by a metal plate, in particular in the form of an aluminum plate, and is attached to the object detection sensor. In this case, the heat transmission element 30 is attached to the multi-part housing by means of a screw connection and forms part of the sensor housing. The screw connection is made by a screw which engages in an opening 34 having a thread.

[0058] The heat absorption element is formed by the holding element 16. In particular, the holding element has reinforcing structures 36. Openings 38 are incorporated in the reinforcing structures 36 on the holding element's 16 side opposite the object detection sensor. These openings 36, in particular drill holes, form a thread so that the object detection sensor can be attached.

[0059] The heat transmission element 30 has a heat transmission surface 40 which faces the heat absorption element 32. The heat absorption element 32, in turn, has a heat absorption surface 42 facing the heat transmission element. The heat transmission surface 40 and the heat absorption surface 42 face each other.

[0060] The cooling device 12 provides cooling by transferring heat energy generated by the electronics to the heat transmission element 30. The heat energy from the electronic components absorbed by the heat transmission element 30 is transferred to the heat absorption surface 42 via its heat transmission surface 40 by means of thermal radiation and is absorbed by the heat absorption element 32. The heat energy absorbed by the heat absorption element 32 is then released to the environment. In addition to transferring the heat energy by thermal radiation, the heat energy is also partially transferred by convection.

[0061] In particular, the heat absorption element 32 in the form of the holding element 16 is fixedly connected to a housing, in particular a module housing of the object detection sensor and the cooling device. Alternatively, the holding element 16 can also be integrally formed by the module housing. Such a module housing advantageously encloses the object detection sensor and the cooling device completely and in a fluid-tight manner.

[0062] The transfer of heat energy from the heat transmission element 30 to the heat absorption element 32 takes place in a non-contact manner via an intermediate space 43. The intermediate space 43 is formed between the heat transmission element 30 and the heat absorption element 32. The object detection sensor is formed such that the heat transmission element 32 and the heat absorption element 32 do not come into abutting contact. This enables frictionless and easy pivoting of the object detection sensor with respect to the holder. The intermediate space 43 provides a clearance between the heat transmission element and the heat absorption element.

[0063] In an alternative variant, a liquid, such as an oil or grease, can be disposed within the intermediate space 43 instead of a gas. Heat transfer then takes place through the thermal conductivity of the liquid.

[0064] A plurality of ribs projecting towards the opposite element are formed on each of the heat transmission element 30 and the heat absorption element 32. The ribs 44 of the heat transmission element are formed as semicircular discs extending in a direction R towards the heat absorption element 32. The direction R extends from the heat absorption element towards the heat transmission element 32. In particular, it is perpendicular to the associated surface portion as shown in FIG. 2. In addition, the heat absorption element also has ribs 46 which are also formed by semicircular discs and extend towards the heat transmission element 30.

[0065] At the heat absorption element 32, some of the ribs 46 transition into the reinforcing structure 36. Accordingly, the ribs 44 facing this reinforcing structure are provided with a recess 44a. This recess 44a is formed such that pivoting of the multi-part housing 14 at the desired pivot angle is still possible in a non-contact manner.

[0066] The ribs 44 and 46 greatly increase the heat transmission surface 40 and the heat absorption surface 42. In this case, each rib 44 of the heat transmission element 30 has two heat transmission undersurfaces 48 and each rib 46 of the heat absorption element 32 has two heat absorption undersurfaces 50.

[0067] Ribs 44 and 46 are arranged opposite to and offset from one another on the heat transmission element 30 and the heat absorption element 32 so that they engage with each other. Accordingly, between two ribs of the one element, one rib of the other element is disposed. In particular, the intermediate space 43 in the illustration of FIG. 2 extends through the ribs in a substantially meandering manner. Accordingly, the ribs 44 and 46 engage with each other alternately, in particular in a comb-shaped manner. Here, a heat transmission undersurface 48 is mostly associated with a heat absorption undersurface 50 of the adjacent rib. Between in each case two ribs of an element, a free space 52 is formed which is part of the intermediate space 43. In particular, a rib of the one element engages in a free space 52 of the other element.

[0068] The disc-shaped ribs are aligned in such a manner that pivoting of the multi-part housing 14 and thus of the sensor system relative to the holding element 16 is made possible. In particular, the opposing ribs do not make abutting contact with one another in any pivoted position. For this purpose, the ribs are formed in a direction of extent which is perpendicular to the direction R and perpendicular to a pivoting direction of the multi-part housing 14.

[0069] Between the ribs arranged opposite and adjacent to one another, a distance of the heat transmission undersurfaces of a few millimeters is possible. Such a distance D can be, for example, 0.5 millimeter, 1 millimeter or even two millimeters. In particular, distances in the range of 0.5 millimeters to 2 millimeters are possible. Such a small distance makes the transmission by thermal radiation particularly effective.

[0070] Furthermore, the ribs 46 and 44 are formed such that they overlap in the radial direction at least partially or to a large extent, thus, at least more than 50%, in the direction R. Alternatively, a heat transmission undersurface 48 and a heat absorption undersurface 50 can overlap over a portion or most of their surface area, thus, at least 50% of their surface area.

[0071] To further optimize heat transfer, the heat transmission element 30 and the heat transmission element 32, in particular the heat transmission surface 40 and the heat absorption surface 42, can be provided with an emission-optimized or absorption-optimized surface. This can be, for example, a coating, a varnish or even a specific texture of the surface.

[0072] Furthermore, when a gas is used within the intermediate space 43, it is also possible to form a fan which circulates the fluid and which circulates the fluid in intermediate space, thereby providing a higher heat transfer via convection.