Optical detection unit having an optical module specifically fastened by means of a hold-down pin, and method

Abstract

One aspect of the invention relates to an optical detection unit (1) comprising a housing (2) having an accommodating space (5) in which at least one optical module (11, 12) is located, wherein the housing (2) has at least one hold-down pin (13) by means of which the optical module (11, 12) is pressed fixedly into a position in at least one spatial direction, and wherein a positioning compensation element (14) is positioned between the optical module (11, 12) and the hold-down pin (13).

Description

[0001] Optical detection unit with an optical module specifically attached with a hold-down dome, and method

[0002] One aspect of the invention relates to an optical detection unit. The optical detection unit has a housing, which can also be referred to as an outer housing. A receiving chamber is formed within the housing, in which at least one optical module is arranged. Another aspect relates to a method.

[0003] In optical detection units, such as LiDAR sensors or laser scanners, it is essential that the components are fixed in position. This is particularly important for the reliable and precise transmission and reception of optical signals. Conventional detection units typically fix the optical module in place by screwing it down. However, this requires additional fasteners in the form of screws and increases assembly effort. Furthermore, it usually increases the weight, and the fixed position is not always guaranteed.

[0004] Mounting on bearing journals simplifies assembly in this context. However, securing the position, especially long-term positioning, is difficult.

[0005] The object of the present invention is to create an optical detection unit in which an optical module can be mounted with minimal effort and is arranged in a positionally fixed position in the housing for the long term.

[0006] This task is solved by an optical detection unit and a method according to the independent claims.

[0007] One aspect of the invention relates to an optical detection unit. The optical detection unit can also be referred to as a laser-based detection unit. It is particularly sensitive in the infrared range. The optical detection unit has a housing. This can also be referred to as an outer housing. A receiving chamber is formed within the housing, in which at least one optical module is arranged. The housing has at least one retaining dome. This dome is designed to hold the optical module. By means of the at least one retaining dome, the optical module is pressed into a position in at least one spatial direction. It is particularly advantageous that a separate positioning compensation element is arranged between the optical module and the retaining dome.This allows for a particularly advantageous and simple way to arrange an optical module in the housing with minimal assembly effort and to maintain its fixed position over the long term. The number of screws can be reduced, and in particular, screws can be eliminated entirely. The preferably rigid, especially along their longitudinal axis, retaining domes ensure simple and stable positioning in at least one spatial direction, i.e., the direction of the hold-down. This is further improved by the positioning compensation element.

[0008] Preferably, the positioning compensation element is designed as an elastic and / or flexible element, so that tolerances can be compensated for by deformation of the positioning compensation element and the optical module can be held under preload.

[0009] In one embodiment, the positioning compensation element is a paste. This is a further advantageous concept, as it allows the paste, designed as an elastic material, to be applied with exceptional precision and thus form-fitting security between the hold-down dome and the optical module during the assembly process. This enables particularly direct mechanical contact even with varying tolerances, since the paste adapts to these individual conditions and can be shaped accordingly.

[0010] It is particularly advantageous if this paste is a thermally conductive paste. This not only allows for highly customized deformation during specific manufacturing processes, but also enables a highly specific curing of this positioning compensation element. This allows the positioning compensation element to be individually cured once it is in its final position and has established direct mechanical contact between the hold-down dome and the optical module. This ensures that the positioning compensation element remains dimensionally rigid and stable after assembly, thus reliably maintaining the fixed final position of the optical module achieved during manufacturing. Furthermore, a thermally conductive paste also facilitates heat dissipation, particularly from the optical module, when it heats up during operation of the optical detection unit.

[0011] In one embodiment, the retaining dome can be designed in a pin-like shape. This makes it both space-saving and lightweight. It also allows for a particularly customized local coupling with the optical module, especially the positioning compensation element. Consequently, the positioning compensation element can be relatively small and delicate, as it is only required where the pin-like retaining dome is located in close proximity to a top surface of the optical module.

[0012] Furthermore, the pin-like design of the hold-down dome also enables a particularly targeted and mechanically stable coupling with a local point.

[0013] On the one hand, the mechanical coupling between a preferably present, at least one bearing pin, an external unit of the optical detection unit, and a pin receptacle on the optical module enables a simple assembly scenario. An additional, separate retaining dome, distinct from the bearing pin, provides further mechanical fixation by acting on the optical module and securing it. This additional positioning compensation element counteracts even minor deviations due to assembly and manufacturing tolerances. Thus, such tolerances can be compensated for, ensuring a particularly secure arrangement of the optical module within the housing, even with a wide range of possible tolerances.This positioning compensation element compensates for any inaccuracies in the mechanical fit, particularly when tolerances between the retaining dome and the optical module, as well as between the bearing pin and the optical module, prevent a direct fit or create a direct but insufficient fit. This additional element and its precise positioning facilitate rapid and effortless assembly and ensure a particularly durable, fixed mounting of the optical module within the housing.

[0014] In particular, the bearing pin enables the optical module to be held in the spatial directions in which the plane of the optical module extends. Specifically, the hold-down dome then fixes the position in the third spatial direction, i.e., perpendicular to the plane of the optical module. This is especially true because the hold-down dome, with its positioning compensation element, acts on the optical module in this perpendicular direction. Specifically, the bearing pin and the hold-down dome are arranged with their longitudinal axes parallel, and in particular coaxially.

[0015] In one embodiment, the bearing journal is conical. This means, in particular, that its dimensions decrease in the axial direction when viewed perpendicular to the longitudinal axis. This tapered front end can then be inserted more easily into the journal receptacle, especially a hole, and in particular through a through-hole in a housing of the optical module.

[0016] A pivot socket can also be a slotted hole in the housing of the optical module. This allows the bearing pin to be moved in a predetermined direction.

[0017] In one embodiment, the bearing journal is arranged on a first housing part of the housing. In particular, the bearing journal is formed integrally with the housing part. This can be the case if the housing part is made of plastic, for example, if it is an injection-molded component.

[0018] In one embodiment, the retaining dome is arranged on a second housing part of the housing, which is separate from the first housing part. In particular, it can be formed integrally with it. Here too, the second housing part can be made of plastic. It can also be an injection-molded component. The two housing parts can be separate from each other.

[0019] Such designs allow the individual housing parts to be customized in terms of material, shape, and / or manufacturing process.

[0020] Furthermore, the assembly of individual components onto a housing part is also simplified.

[0021] In one embodiment, the two housing parts are connected by a detachable connection. This detachable connection can be a mechanical connection, and it is particularly non-destructive. This means that the connection can be reversibly disconnected and reconnected without losing functionality. In another embodiment, the detachable connection can be a screw connection, in which case the two housing parts are screwed together. In yet another embodiment, the optical module is held in the housing without screws. This means that it is mounted in the housing without screws. Specifically, this is achieved solely by attaching the optical module to several bearing pins and holding it in place with one or more retaining bosses.

[0022] A screw connection is also possible, or a maximum of two screw connections are possible, with which the optical module is held in addition to at least one retaining dome.

[0023] The optical module can be a laser module or a receiver module.

[0024] In one embodiment, the optical detection unit is a LiDAR sensor. Specifically, the optical detection unit is a vehicle detection unit. This means that it is intended for use and / or installation on a vehicle, such as a motor vehicle. With such optical detection units, for example, the surroundings of a vehicle can be detected. Object detection, in particular, is very advantageous.

[0025] The optical detection unit comprises, in particular, a laser unit or laser module and a receiving unit or receiver module. The laser unit emits electromagnetic radiation in a wavelength range between 800 nm and 1600 nm, specifically 850 nm, 905 nm, or 1550 nm.

[0026] Another aspect of the invention relates to a method for mounting an optical detection unit. The optical detection unit can be configured in particular according to the aspect mentioned above or in an advantageous embodiment thereof. The method comprises, in particular, the following steps:

[0027] Providing a first housing part of a housing of the optical detection unit, wherein the first housing part has at least one bearing pin;

[0028] Providing a second housing part of the housing of the optical detection unit, wherein the second housing part has at least one retaining dome; attaching at least one optical module of the optical detection unit into the first housing part, in particular into a mounting position on a bearing device, in particular such that a bearing pin of the first housing part engages in a pin receptacle of the optical module;

[0029] Applying a positioning compensation element to a top side of the optical module and / or to the hold-down dome;

[0030] Applying one housing part to the other housing part in such a way that the housing is formed and the optical module is fixed in its position in a spatial direction in the first housing part and the positioning compensation element is arranged between the optical module, in particular directly resting on it, and the holding dome, in particular a front end of the holding dome facing the optical module.

[0031] This method enables a very targeted, in particular screwless or screw-reduced mounting of the optical module in the housing, while still allowing for a particularly fixed arrangement of the optical module.

[0032] It can be provided that, when the second housing part is applied to the first housing part, these housing parts, or one housing part in particular, are brought closer to the other by a linear assembly movement. The positioning compensation element, which is still elastically deformable in this state, in particular the paste, preferably the thermally conductive paste, enables a highly situation-dependent, form-fitting, and adapted, and thus preferably also void- and bubble-free, filling of the area between the hold-down dome and the circuit board. Therefore, the positioning compensation element is also, in a very specific way, a filling element or a spacer compensation adapter element. Once the final position is reached, this positioning compensation element can be cured in a further step of the process. This can be done, for example, by thermal and / or optical and / or electrical influence.

[0033] Furthermore, the thermal paste also advantageously creates a heat dissipation element. For example, the thermal paste also dissipates heat generated during the operation of the optical detection unit.

[0034] Advantageous embodiments of the optical detection unit, such as

[0035] Positions of elements and / or of elements relative to each other are also to be regarded as advantageous embodiments of the method, and vice versa. The assembly process steps are carried out in such a way that these positions are achieved.

[0036] Exemplary embodiments of the invention are explained in more detail below with reference to schematic drawings. These show:

[0037] Fig. 1 . an exploded view of an embodiment of an optical detection unit according to the invention;

[0038] Fig. 2 shows a top view of the first housing part with optical modules;

[0039] Fig. 3 shows a cross-sectional view according to Fig. 2 in the assembled final state of the optical detection unit;

[0040] Fig. 4a shows an enlarged view of a section in Fig. 3, in which the mounted state of the optical module of the optical detection unit is shown; and

[0041] Fig. 4b shows an enlarged view of another sub-area in Fig. 3, in which the mounted state of the optical module of the optical detection unit is shown.

[0042] In the figures, identical or functionally equivalent elements are given the same reference symbols.

[0043] Figure 1 shows an exploded view of an embodiment of an optical detection unit 1. This unit is a vehicle detection unit, specifically a LiDAR sensor. The optical detection unit 1 has a housing 2. The housing 2 comprises a first housing part 3 and a separate second housing part 4. When the housing 2 is closed, with the two housing parts 3 and 4 abutting and connected, a receiving chamber 5 is formed, or rather, bounded by the walls of the housing parts 3 and 4. At least one circuit board 6 of the optical detection unit 1 is arranged in this receiving chamber 5.

[0044] In the exemplary embodiment, the optical detection unit 1 has at least one bearing pin 7, preferably several such bearing pins 7, as shown in Fig. 2. In the exemplary embodiment, these are arranged on the first housing part 3. In particular, they are formed integrally with the first housing part 3. The housing parts 3 and / or 4 can, for example, be made of die-cast aluminum.

[0045] Furthermore, optical modules are also arranged in the first housing part 3 in Figures 1 and 2. One optical module is a receiver module 11 and another optical module is a laser module 12. The laser module 12 emits laser light. The laser light is directed outwards by a rotating mirror 10 of the optical detection unit 1. Laser light reflected in the surroundings is directed by the mirror 10 to the receiver module 11.

[0046] Figure 1 shows a configuration in which the optical modules, and thus here the laser module 12 and / or the receiver module 11, are already arranged in the first housing part 3 and are preferably mounted on at least one bearing pin 7, and in particular on two bearing pins 7. For this purpose, the optical modules have pin receptacles 8. These are, in this case, a through hole 9a and an elongated hole 9b.

[0047] As can also be seen in Fig. 1, the optical detection unit 1 also has at least one hold-down dome 13. In particular, several hold-down domes 13 are formed here. The position and number are only to be understood as examples.

[0048] The retaining domes 13 press down on the optical modules from above when the housing 2 is closed and thus in the end positions of the optical modules. This occurs at specific local counterpoints 15 (Fig. 2). Three counterpoints 15 are shown here as an example for the laser module 12. In particular, these can be the points that were previously screw connections. At least one of these three points is now not a screw connection and is designed screwless with the retaining dome 13. Therefore, a maximum of two screw connections can be used at these three mechanical retaining and coupling points. However, there can also be only one or no screw connection. The number of retaining domes 13 is then correspondingly higher.

[0049] A corresponding feature can be provided optionally or additionally at the receiver module 11. There, too, three counterparts 15 are provided as examples, both locally and in number. Here, too, a maximum of two are designed as areas for screw connections, and at least one is intended for contact with the retaining dome 13. These retaining domes 13 then press down from above onto the surfaces of the optical modules, so that these are pressed against bearing devices 16 (Fig. 1) in the first housing part 3.

[0050] As can be seen, the retaining domes 13 are pin-shaped. In particular, they are formed integrally with the second housing part 4.

[0051] As can also be seen in Fig. 1, the optical detection unit 1 has a positioning compensation element 14. This is preferably arranged at a free end of a hold-down dome 13. A positioning compensation element 14 can be a paste, in particular a thermally conductive paste. It can be a flat cylindrical element, as shown by way of example in Fig. 1. The size of the flat cylinder can be adapted to the front end or the surface of the front end of a hold-down dome 13.

[0052] This ensures that a hold-down dome 13 with a positioning compensation element 14 only locally meets a top surface of an optical module at one point, in particular at a counterpart 15.

[0053] Figure 3 shows a sectional view of the assembled final state of the optical detection device 1. It can be seen that the hold-down domes 13 with the positioning compensation elements 14 rest on the surfaces of the optical modules.

[0054] This ensures that the fixed position of the optical modules is achieved and maintained permanently. In particular, this positioning compensation element 14 can then also be cured.

[0055] Figures 4a and 4b show enlarged views of areas in Figure 3, in which the hold-down domes 13 and the positioning compensation element 14 can be seen.

Claims

Patent claims 1. Optical detection unit (1) with a housing (2) in which a receiving chamber (5) is formed in which at least one optical module (11 , 12) is arranged, characterized in that the housing (2) has at least one hold-down dome (13) with which the optical module (11 , 12) is pressed into a position in at least one spatial direction, wherein a positioning compensation element (14) is arranged between the optical module (11 , 12) and the hold-down dome (13).

2. Optical detection unit (1) according to claim 1 , characterized in that the positioning compensation element (14) is designed as an elastic and / or flexible element.

3. Optical detection unit (1) according to claim 1 or 2, characterized in that the positioning compensation element (14) is a paste.

4. Optical detection unit (1) according to claim 3, characterized in that the paste is a thermally conductive paste.

5. Optical detection unit (1) according to one of the preceding claims, characterized in that the optical module (11 , 12) is arranged in a first housing part (3) of the housing (2), in particular on a bearing device (16) in the first housing part (3).

6. Optical detection unit (1) according to claim 5, characterized in that the retaining dome (13) is arranged on a second housing part (4) of the housing (2) which is separate from the first housing part (3), in particular it is formed integrally with it.

7. Optical detection unit (1) according to claims 5 and 6, characterized in that the two housing parts (3, 4) are detachably connected to each other, in particular screwed together.

8. Optical detection unit (1) according to one of the preceding claims, characterized in that the hold-down dome (13) is designed in a pin-like manner.

9. Optical detection unit (1) according to one of the preceding claims, characterized in that the optical module (11 , 12), in particular only, is pressed into a position fixed by several hold-down domes (13) in at least one spatial direction.

10. Optical detection unit (1) according to one of the preceding claims, characterized in that the optical module (11 , 12) is additionally fixed in position by a maximum of one screw connection or by a maximum of two screw connections.

11. Optical detection unit (1) according to one of the preceding claims, characterized in that the optical detection unit (1) comprises a laser module (12) and / or a receiver module (11) as an optical module.

12. Optical detection unit (1) according to one of the preceding claims, characterized in that it is a LIDAR sensor.

13. Method for mounting an optical detection unit (1), in particular according to one of the preceding claims, comprising the following steps: Providing a first housing part (3) of a housing (2) of the optical detection unit (1); Providing a second housing part (4) of the housing (2) of the optical detection unit (1), wherein the second housing part (4) has at least one retaining dome (13); Attaching an optical module (11, 12) of the optical detection unit (1) to the first housing part (3), in particular to a mounting position on a bearing device (16), especially such that a bearing pin (7) of the first housing part (3) engages in a pin receptacle (8) of the optical module (11, 12); applying a positioning compensation element (14) to a top surface of the optical module (11, 12) and / or to the hold-down dome (13); Applying one housing part (3, 4) to the other housing part (3, 4) such that the housing (2) is formed and the optical module (11, 12) is fixed in its position in a spatial direction in the first housing part (3) and the positioning compensation element (14) is arranged between the optical module (11, 12), in particular directly resting on it, and the retaining dome (13), in particular a front end of the retaining dome (13) facing the optical module (11, 12).

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