Device for protecting an optical sensor and corresponding driving assistance system

Abstract

The invention relates to a device (3) for protecting an optical sensor (13) of a driving assistance system of a motor vehicle, the optical sensor (13) comprising optics (14), the device (3) comprising: an optical element (9) configured to be arranged upstream of the optics (14) of the optical sensor (13) and mounted so as to be able to rotate about a first axis of rotation (A1), and an electric motor (5) configured to rotate the optical element (9). According to the invention, the electric motor (5) comprises a rotor (51) configured to rotate about a second axis of rotation (A2) intersecting the first axis of rotation (A1) of the optical element (9). The invention also relates to a corresponding driving assistance system.

Description

[0001] This invention relates to the field of driver assistance, and more particularly to a driver assistance system installed in a particular vehicle, which may include an optical sensor, such as a camera including an objective lens, particularly including at least one lens. More specifically, this invention relates to a device for protecting such an optical sensor. The invention also relates to a method for assembling such a protective device.

[0002] Currently, many motor vehicles are equipped with forward-facing cameras, rear-facing cameras, or even side-facing cameras. These cameras are specifically part of driver assistance systems, such as parking assistance systems or even systems used to detect lane departure.

[0003] As is well known, cameras are mounted inside the passenger compartment of a vehicle, near the rear windshield / window, and pointing backward through the rear windshield. These cameras are well protected from external weather events and dirt caused by organic or inorganic contaminants. However, the viewing angle of such cameras mounted inside the passenger compartment is not optimal, especially for parking assistance systems, for example, because they cannot see obstacles located near the rear of the vehicle.

[0004] For this reason, the camera for the driver assistance system is preferably mounted in different locations on the exterior of the vehicle, depending on the intended use, such as in the front or rear bumper area, or in the front or rear license plate area. In this case, the camera is therefore highly exposed to splashing organic or inorganic dirt, which may deposit on the camera's optics and thus reduce the camera's effectiveness, or even render it malfunctioning. In particular, splashing rainwater and dirt have been observed in wet weather, which can significantly affect the operability of driver assistance systems that include such cameras. The surfaces of the camera's optics must be cleaned to ensure that the camera remains in good working order.

[0005] To combat the buildup of dirt on cameras, a known practice is to place equipment near the camera for cleaning its optics, typically a cleaning fluid sprayer, to remove contaminants that accumulate over time. However, using these sprayers increases the operating costs of such driver assistance systems because they require a considerable amount of cleaning fluid.

[0006] Another solution involves housing the camera within a protective device. However, this protective device has a very large installation footprint. Reducing footprint is a perennial goal in the automotive industry, and more specifically in the field of driver assistance systems.

[0007] The present invention proposes to overcome at least part of the above-mentioned disadvantages by providing an alternative device for protecting optical sensors, thereby preventing dirt from depositing on optical sensors (such as cameras), and the arrangement of the device is optimized to reduce its footprint.

[0008] For this purpose, the present invention relates to an optical sensor for protecting a driver assistance system of a motor vehicle, the optical sensor comprising optical elements, the device comprising: - An optical element configured to be positioned upstream of the optical components of an optical sensor and rotatably mounted about a first rotation axis, and - A motor, particularly an electric motor, configured to rotate the optical element.

[0009] According to the invention, the motor includes a rotor configured to rotate about a second rotation axis that intersects a first rotation axis of the optical element.

[0010] This arrangement allows for a reduction in the space occupied by the protective equipment and is particularly advantageous for positioning the protective equipment in a single housing for assembly on a motor vehicle.

[0011] Devices for protecting optical sensors may further include, individually or in combination, one or more of the following features: -The second axis of rotation of the motor is substantially perpendicular to the first axis of rotation of the optical element; - The optical elements are at least partially transparent; - The optical components are separated from the optical sensor; - The optical element is configured relative to the optical device of the optical sensor such that the first rotation axis of the optical element is parallel to or coincides with the optical axis of the optical sensor; - The optical element is configured to be arranged relative to the optical sensor such that the first rotation axis of the optical element coincides with the optical axis of the optical sensor; - The device includes at least one means for transmitting the motion of the motor's rotor to an optical element; - The transmission device includes at least two sprockets, including a first sprocket configured to be driven by the rotor of the motor and configured to drive a second sprocket; - The device includes a housing configured to house an optical sensor and a motor; - The optical sensor and motor are housed within a single recess in the housing; -The housing is configured to receive the at least one transmission device; - The optical sensor, the motor, and the at least one transmission device are housed within a single recess of the housing; - The device further includes a module for generating and / or spraying air onto at least one area of ​​the optical element; - The air generation and / or injection module is configured to generate and inject a jet of compressed air; - The compressed air jet preferably has a pressure of less than 10 bar; - The air generation and / or injection module is configured to generate a predetermined volume of air, such as approximately 10 ml; - The air generation and / or injection module includes at least one air nozzle; - The air nozzle is fixedly arranged relative to the optical element; - The air nozzles are arranged such that they spray air jets onto the central region of the optical element; - The air generation and / or injection module includes at least one air generation component; - The at least one air generating component is selected from at least a piston, a pump, an air reservoir, and an impeller; - The air generation and / or injection module includes at least one valve or solenoid valve; - The air generation and / or injection module includes at least one pump for generating an air jet and an air reservoir connected to the pump for storing the air jet generated by the pump; - The air generation and / or injection module further includes at least one valve connected to the air reservoir and the nozzle, thereby enabling the air jet sent to the nozzle to be adjusted to a predetermined air volume and pressure; -The housing is configured to receive the at least one air-generating member; - At least one air-generating component is received within the same recess as the optical sensor, and / or the motor, and / or the at least one transmission device; - The optical element has at least one surface, which is configured to be positioned in the field of view of the optical sensor; - The optical element has at least one surface that is at least partially planar or substantially planar, which is configured to be positioned in the field of view of the optical sensor; - The optical element has at least one surface that is at least partially spherical or substantially spherical, which is configured to be positioned in the field of view of the optical sensor; - The optical element has at least one partially aspherical surface, which is configured to be positioned in the field of view of the optical sensor; - The extent of the at least one surface is greater than or equal to the field of view of the optical sensor; - The optical element is positioned to be centered relative to the first axis of rotation.

[0012] The present invention also relates to a driving assistance system including an optical sensor comprising optical elements. According to the invention, the system includes the device described above for protecting the optical sensor.

[0013] Further features and advantages of the invention will become more apparent from the following description, given by way of illustrative and non-limiting example and in conjunction with the accompanying drawings, in which: -[ Figure 1 A motor vehicle including a driving assistance system according to the present invention is illustrated schematically. - [Figure 2] is a perspective view of the device used to protect the optical sensor. Figure 3 is an exploded view of the protective device in Figure 2, wherein the housing that houses the different components of the device has been removed. -[ Figure 4 The optical elements and air nozzles of the device are shown schematically. -[ Figure 5a A schematic side view of an optical element with a drop of water is shown. -[ Figure 5b This schematically illustrates the process following the jet of air. Figure 5a Optical elements in ] -[ Figure 6a The diagram schematically illustrates the area of ​​the optical element subjected to the air jet, and -[ Figure 6b The diagram schematically illustrates the optical element and the surface subjected to the air jet after the optical element rotates.

[0014] In these figures, the same elements have the same reference numerals.

[0015] The following embodiments are examples. Although the specification relates to one or more embodiments, this does not necessarily mean that every reference numeral refers to the same embodiment, or that these features apply only to one embodiment. Individual features of different embodiments may also be combined or interchanged to provide other embodiments.

[0016] In the specification, certain components may be assigned ordinal numbers, such as first component or second component. In this case, the ordinal numbers are merely used to distinguish and indicate similar but not identical components. Such ordinal numbers do not imply that one component takes precedence over another, and these numbers can be easily interchanged without departing from the scope of this specification. Similarly, such ordinal numbers do not imply any temporal order.

[0017] [ Figure 1 The image shows a motor vehicle 100, which is provided with at least one driving assistance system 1 according to the present invention.

[0018] The driving assistance system 1 specifically includes at least one optical sensor 13 and a device 3 for protecting the optical sensor 13, which is more clearly visible in [Figures 2] and [Figures 3].

[0019] The optical sensor 13 is, for example, an image acquisition optical sensor 13 (such as a camera). The optical sensor can be a CCD (charge-coupled device) sensor or a CMOS sensor including a miniature photodiode array. According to another variant, the optical sensor can be a LIDAR (light detection and ranging) sensor.

[0020] As can be seen more clearly in [Figure 3], the optical sensor 13 includes an optical element 14 having an optical axis 15. The optical element 14 is, for example, an objective lens. The objective lens may include at least one lens, particularly multiple lenses, depending on the field of view and resolution, for example between two and ten lenses, typically four or five lenses, or even ten lenses in the case of a fisheye. For example, in the case of a fisheye, at least one lens of the optical element 14 is, for example, convex (curved), with its convexity oriented towards the outside of the optical sensor 13.

[0021] A holder 17 for the optical sensor 13 may also be provided. This holder 17 is arranged behind the optical sensor 13, on the side opposite to the optical device 14.

[0022] In the illustrated embodiment, the optical sensor 13 is intended to be mounted in the protective device 3. More precisely, the optical sensor 13, and particularly its retainer 17, is intended to be fixedly mounted in the protective device 3.

[0023] Furthermore, the protective device 3 may include a mounting member 31 designed to be fastened to the housing 6', to which the holder 17 of the optical sensor 13 is fastened. For this purpose, an opening 33 may be formed in the mounting member 31 to receive the shaft of the holder 17.

[0024] according to[ Figure 1 As shown in the example, the protective device 3 is installed at the front of the motor vehicle 100, in the area of ​​the bumper. Of course, as a variation, the protective device 3 can be installed at the rear of the motor vehicle 100, for example, in the area of ​​the bumper or license plate. The protective device can also be installed, for example, on the side of the vehicle, for example, in the area of ​​the rearview mirror.

[0025] The protective device 3 can be fastened to any component 2 of the vehicle 100 using any known technology, such as body components or external components (e.g., bumpers, rearview mirrors, or license plates). This can include, but is not limited to, clip systems, screw systems, or even adhesive bonding systems.

[0026] Protective equipment More precisely, referring again to [Figure 2] and [Figure 3], protection device 3 includes: -At least one accessory 4 of motor vehicle 100 (also refer to [… Figure 1 This accessory 4 is rotatably mounted around the first rotation axis A1 and has the function of protecting the optical sensor 13, and -Actuator, more precisely motor 5, especially electric motor, which is configured to rotate accessory 4.

[0027] Therefore, protection device 3 is a mobile device.

[0028] The protective device 3 advantageously further includes a housing 6' ([FIG. 2]) for holding all the elements of the protective device 3 in place. The housing 6' may also include an optical sensor 13.

[0029] Specifically, the protective device 3 may include a first sub-component and a second sub-component, which are assembled together and arranged within the housing 6'. The first sub-component may include an accessory 4. The second sub-component may include a motor 5.

[0030] appendix Annex 4 or the protective device may be at least partially transparent.

[0031] In the described embodiment, Annex 4 includes optical element 9 (see [Figure 2] and [Figure 3]).

[0032] Optical element 9 is designed to protect the optical element 14 of optical sensor 13 from potential splashes of dirt or solid debris that could damage it. Therefore, the optical element is an element used to protect optical sensor 13, or more precisely, a shield used to protect the optical sensor. For this purpose, optical element 9 is positioned upstream of the optical element 14 of optical sensor 13. In this text, the term "upstream" is defined relative to the optical axis 15 and relative to the road scene image acquired by optical sensor 13. In other words, "upstream" of optical element 14 is given as the position where optical element 9 is positioned along the optical axis 15 between optical element 14 and the road scene image acquired by optical sensor 13. It is this optical element 9 that is subjected to external attacks, namely splashes of water and contaminants, stone chips, and contaminant deposits or watermarks.

[0033] The dimensions of the optical element 9 are advantageously determined to cover the entire surface of the optical device 14. Therefore, the optical element 9 is arranged within the field of view of the optical sensor 13. For this purpose, the optical element 9 is advantageously at least partially transparent so as not to adversely affect the effectiveness of the optical sensor 13. The optical element 9 may be made of glass or a transparent plastic (such as polycarbonate). The optical element 9 has at least one surface 9a, 9b (see […]). Figure 5a ]and[ Figure 5b The at least one surface is centered in this case and is intended to be positioned at least partially facing the optical element 14. Referring again to [Figures 2] and [3], the optical element 9 has a peripheral edge 90 that is intended to at least partially surround the optical element 14.

[0034] Optical element 9 can be arranged to be centered relative to optical sensor 13, or more precisely, relative to optical device 14. Optical element 9 is arranged such that its optical axis 91 is parallel to, or even coincides with, the optical axis 15 of optical sensor 13.

[0035] In the described embodiment, the optical element 9 is separated from the optical sensor 13.

[0036] This optical element 9 has an optical axis 91.

[0037] According to the example shown, when the protective device 3 is installed at the front of the vehicle 100, the optical element 9 is arranged at the front of the protective device 3, oriented towards the front of the vehicle 100. In other words, the optical element 9 is arranged at the front of the accessory 4, or at the front of the housing 6'. "The front of the protective device 3" refers to the portion of the protective device 3 intended to face the road scene image acquired by the optical sensor 13 when the protective device 3 is installed on the vehicle 100. Figure 1 ]).

[0038] Of course, as a variant, the optical sensor 9 can be oriented toward the rear of the motor vehicle 100, or it can be mounted on the side of the vehicle, for example, in the area of ​​the rearview mirror.

[0039] Furthermore, the optical element 9 is arranged such that it is rotated by the motor 5 to allow it to be cleaned via centrifugal effect. When the protective device 3 and the optical sensor 13 are mounted in the housing 6', the optical element 9 is advantageously positioned such that its rotation axis A1 is parallel or substantially parallel to the optical axis 15 of the optical sensor 13. Advantageously, the first rotation axis A1 of the optical element 9 coincides with the optical axis 15 of the optical sensor 13. This first rotation axis A1 is also parallel or coincident with the optical axis 91 of the optical element 9.

[0040] Optical element 9 can be positioned centered relative to the first rotation axis A1. This optical element 9 specifically has rotational symmetry about the first rotation axis A1.

[0041] Furthermore, when the protective device 3 that receives the optical sensor 13 is installed on the vehicle 100 (see also […]), Figure 1 Optical devices 14 and optical elements 9 advantageously protrude from openings provided in elements 2 of vehicle 100.

[0042] The optical element 9 may further have at least one surface 9a, 9b, which is configured to be at least partially located within the field of view of the optical sensor 13. The extent of this surface 9a, 9b is advantageously greater than or equal to the extent of the field of view of the optical sensor 13.

[0043] According to one embodiment, these surfaces 9a and 9b are at least partially or even completely planar in the field of view of the optics 14 of the optical sensor 13. Optical elements 9 that are at least partially planar can be easily manufactured.

[0044] As a variant, at least one surface 9a, 9b is at least partially spherical or substantially spherical in the field of view of the optical sensor 13.

[0045] According to another variant, at least one surface 9a, 9b is at least partially aspherical in the field of view of the optical sensor 13.

[0046] Specifically, according to the described embodiment, the optical element 9 includes an inner surface 9a and an outer surface 9b, which are opposite to each other. Figure 5a ]and[ Figure 5b These surfaces 9a and 9b can be seen more clearly in the image. The inner surface 9a of the optical element 9 is the surface that is designed to face the optical device 14 of the optical sensor 13.

[0047] Referring also to [Figures 2] and [3], when the optical sensor 13 is housed in the housing 6', the inner surface 9a and the outer surface 9b are partially or completely located within the field of view of the optical sensor 13. The inner surface 9a and the outer surface 9b may be parallel. Surfaces 9a and 9b are advantageously centered relative to the optical sensor 13, and more precisely, relative to the optics 14.

[0048] Furthermore, to prevent condensation from forming between the optical device 14 and the optical element 9, the inner surface 9a of the optical element 9 advantageously has anti-fogging properties. In particular, the inner surface 9a of the optical element 9 has an anti-fogging coating.

[0049] As variations or additions, the inner surface 9a and / or outer surface 9b of the optical element 9 may have one or more of the following properties: hydrophobic, infrared filtering, photocatalytic, superhydrophobic, lipophobic, hydrophilic or even superhydrophilic, stone chip resistant, or any other surface treatment that allows for reduced dirt adhesion. In particular, by virtue of the hydrophobic properties of the outer surface of the optical element 9, any water droplets will flow away from the outer surface without leaving a trace, as water will not be able to adhere to this outer surface. Therefore, a layer or coating on the outer surface 9b of the optical element 9 allows for the limitation of potential adhesion of organic or inorganic contaminants that may adversely affect the satisfactory operation of the driving assistance system 1, as well as the presence of watermarks on the optical element 9. Advantageously, a liquid solution (such as a Rain-X® type solution) can be deposited on the outer surface 9b of the optical element 9 to form a hydrophobic film. These exemplary embodiments are given by way of non-limiting illustration. For example, those skilled in the art may use a transparent optical element 9 with other properties on its outer surface 9b that allow for the limitation of dirt adhesion to this outer surface 9b without departing from the scope of the invention.

[0050] Optionally, the optical element 9 may also include an integrated defrosting or defogging system, such as a defrosting filament or resistor, so as to ensure that the driving assistance system 1 can operate satisfactorily under all weather conditions.

[0051] Advantageously, at least one device for limiting condensation is provided, hereinafter referred to as an anti-condensation device (not shown in the figures). This anti-condensation device may be disposed on the edge of the optical element 9, at least partially surrounding the optical element 14. As a non-limiting example, the anti-condensation device may include at least one through-hole. Preferably, when multiple holes are provided, these holes are arranged symmetrically with respect to the rotation axis A1 of the optical element 9. Furthermore, one or more semi-permeable membranes (not shown) may be provided, each arranged in a straight line with the hole. These membranes are air-permeable and impermeable, thus promoting satisfactory ventilation between the optical element 14 and the optical element 9, and therefore preventing the accumulation of condensation.

[0052] Furthermore, according to a variant embodiment not shown, the protective device 3 may further include a rotating housing rigidly connected to the optical element 9, the rotating housing being designed to be rotated by a motor 5 via a transmission 7. This rotating housing may, in particular, be a rotating housing capable of at least partially accommodating the optical sensor 13.

[0053] drive Regarding motor 5, it is advantageous that it is a small, or even miniature, motor.

[0054] Within the scope of this invention, "small motor" refers to a stepper motor, actuator, brushed or brushless DC motor, asynchronous motor or synchronous motor weighing less than 10 kg or even less than 1 kg, which are particularly used to actuate equipment in vehicles.

[0055] Within the scope of this invention, "miniature motor" refers to a stepper motor, actuator, brushed or brushless DC motor, asynchronous motor, or synchronous motor that weighs less than 200 g or even less than 100 g, preferably between 30 g and 100 g, and for example between 30 g and 70 g.

[0056] As a non-limiting example, motor 5 may be more specifically a brushless motor.

[0057] The rotational speed of motor 5 can be between 1,000 and 50,000 rpm, preferably between 5,000 and 20,000 rpm, and even more preferably between 7,000 and 15,000 rpm. This rotational speed allows any dirt deposited on the optical element 9 to be removed via centrifugal effect, and thus makes it possible to keep the optics 14 of the optical sensor 13 clean to ensure optimal operation of the driver assistance system 1. According to a particularly advantageous embodiment described below, the rotational speed can be reduced to approximately 4,000 to 5,000 rpm.

[0058] For example, power is supplied to motor 5 via a power source connected to the universal circuitry of vehicle 100 (see also […]). Figure 1 ]).

[0059] Referring again to Figures 2 and 3, the motor 5 is rotatably mounted about a second rotation axis A2. The motor 5 includes a rotor 51 and a fixed stator 53, the rotor 51 being rotatable relative to the fixed stator 53. The rotor 51 has a rotation axis 510. According to the illustrated embodiment, the stator 53 is positioned around the rotor 51. Therefore, the stator 53 is external, and the rotor 51 is internal.

[0060] Motor 5 is configured to rotate accessory 4, namely optical element 9 in this example.

[0061] Motor 5, specifically rotor 51, is rotatably mounted about a second rotation axis A2. For example, motor 5 is arranged such that its rotation axis A2 intersects the rotation axis A1 of optical element 9 and the optical axis 15 of optical sensor 13. More specifically, motor 5 is arranged such that its rotation axis A2 is perpendicular or substantially perpendicular to the first rotation axis A1 of optical element 9 and the optical axis 15 of optical sensor 13. This arrangement allows for a compact assembly housed within housing 6'.

[0062] In this configuration, the protective device 3 includes at least one means 7 for transmitting the motion of the motor's rotating shaft to the optical element. According to the illustrated example, the transmission 7 includes at least two sprockets or gears 71 and 73. The first sprocket 71 is positioned such that it can rotate about a second rotating shaft A2. The second sprocket 73 is positioned to mesh with the first sprocket 71 and is also positioned such that it can rotate about a first rotating shaft A1. A rotating shaft 510 is coupled to the first sprocket 71 to allow it to rotate about the second rotating shaft A2. This first sprocket 71, in turn, allows the second sprocket 73 to rotate about the first rotating shaft A1. The first sprocket 71 can be mounted on the mounting member 31 by inserting a bearing (such as a ball bearing 75).

[0063] The second sprocket 73 is configured to rotate the optical element 9. Specifically, another bearing, such as a ball bearing 77, may be provided between the second sprocket 73 and the optical element 9 (particularly the peripheral edge 90 of the optical element 9). The second sprocket 73 has a central aperture for at least partially receiving the optical element 9 and the bearing 77.

[0064] For a compact arrangement, the second sprocket 73 can also be positioned around the optical element 14 of the optical sensor 13.

[0065] Air generation and / or injection module According to a particular embodiment, the protective device 3 further includes an air generation and / or jetting module 8. This module 8 is adapted to generate and / or jet at least one air jet onto at least one area of ​​the optical element 9. The air jet jet jetted onto the optical element 9 is generated by […]. Figure 4 ]and[ Figure 5b The arrow in ] F express.

[0066] Specifically, an air jet is a jet of compressed air. F compressed air jet F Specifically, it has a pressure of less than 10 bar, for example between 1 bar and 2 bar, and preferably about 1.5 bar.

[0067] The air generation and / or injection module 8 ([Figure 2] and [Figure 3]) is also configured to generate a predetermined volume of air, for example, about 10 ml.

[0068] For this purpose, the air generation and / or injection module 8 includes at least one air nozzle 81, visible in [Figure 2] and [Figure 3] and in […]. Figure 4 ]、[ Figure 5b ]and[ Figure 6a ]and[ Figure 6b It is shown very schematically in the image.

[0069] An air nozzle 81 is fixedly arranged relative to the optical element 9. This air nozzle 81 is located above the optical element 9, as shown in [Figure 2] to [Figure 3]. Figure 4 ]and[ Figure 5b ]to[ Figure 6b The positioning of the components in the image corresponds to the final arrangement on the motor vehicle. The air nozzle 81 is specifically arranged near the optical element 9.

[0070] Furthermore, the air nozzle 81 is arranged such that it jets air. F The air is sprayed at least onto the central region of the optical element 9. Specifically, the air nozzle 81 is arranged such that it jets air... F It is sprayed onto the central region and optionally onto the lower region of the optical element 9. The term "lower" is a reference […]. Figure 6a The location of the components is indicated by the position of the components. The lower region corresponds to the region furthest from the air nozzle 81. The entire area of ​​the outer surface 9b of the optical element 9 (air jet) F (Sprayed into the area) is called Z1 and in [ Figure 6a The shape of the air nozzle 81 can be modified to adjust the air jet. (This is shown schematically in the image.) F For those subjected to air jets F area Z1 This representation is highly illustrative, and in particular, since optical element 9 is rotatable, it is clear that optical element 9 is subjected to air jets. F area Z1 They are not the same during rotation.

[0071] According to the example shown, the air nozzle 81, in particular, can have a generally conical shape at its end, resulting in a jet of air being ejected. F Reaching the approximate triangular or V-shaped area of ​​optical element 9 Z1 In this example, refer to [ Figure 6a The positioning of the outer surface 9b of the optical element 9 is such that the vertex of the triangle shape is flush with or close to the center of the outer surface 9b of the optical element 9, and the base of the triangle shape is flush with the lower part.

[0072] refer to[ Figure 5a ]and[ Figure 5b ], jet of air F This allows for the removal of any small water droplets 10 remaining at or substantially at the center of the optical element 9. (Air jet) F It can be sprayed evenly onto the outer surface 9b of the optical element 9.

[0073] Specifically, the air generation and / or jetting module 8 can be implemented while the optical element 9 rotates. Combined with the rotation of the optical element 9, all or almost all of the outer surface 9b of the optical element 9 is jetted with air. F Scan, as if by [ Figure 6b The circular area in ] Z2 This is shown schematically.

[0074] A jet of advantageous compressed air ejected by air nozzle 81 F The rotation of optical element 9 ensures optimal cleaning of the optical element. Small water droplets or dirt closer to or near the center of optical element 9 may be more difficult to remove because the rotational speed at the center may not be sufficient to remove them. These water droplets... Figure 5a ]and[ Figure 5b The diagram is schematically shown and indicated by reference numeral 10. To eliminate these small water droplets at the center, the rotation must be very fast, for example, greater than 10,000 revolutions per minute. As an alternative, by spraying a small volume of compressed air over a certain time interval, for example, 10 ml of compressed air at 1.5 bar, i.e., 100 ms in the described case, to release the predetermined 10 ml of compressed air, during the time taken to release this given air volume, all or almost all of the outer surface 9b of the optical element 9 is exposed to the air jet. F It may be repeated once or multiple times, for example, six or seven times.

[0075] This allows water droplets 10 to be removed not only from the center of the outer surface 9b of the optical element 9, but also from its periphery. Since the air jet, combined with the rotation of the optical element 9, cleans the optical element, the speed of the motor 5 can be reduced, specifically to about 4,000 to 5,000 revolutions per minute.

[0076] Of course, the example of 10 ml of air at a pressure of 1.5 bar is an illustrative and non-limiting embodiment. The volume and pressure values ​​can be adjusted, specifically with consideration for minimizing the protective device 3.

[0077] According to another embodiment, it is conceivable that air is continuously sprayed onto the outer surface 9b of the optical element 9.

[0078] In addition, according to variants not shown, the protective device 3 may include multiple nozzles, specifically for spraying another fluid (such as a cleaning fluid).

[0079] The air generation and / or injection module 8 also includes at least one air generation component. The air generation component may be, for example, an external component not attached to the motor 5. The air generation component may include, but is not limited to, one or more pistons, one or more pumps, one or more air reservoirs, or one or more impellers. The air generation and / or injection module 8 may also include one or more valves or solenoid valves.

[0080] According to another specific example shown in [Figure 2] and [Figure 3], the air generation and / or injection module 8 includes: - At least one pump 83 or micro pump to generate an air jet, and - Air reservoir 85, which is connected to pump 83 to store the air jet generated by pump 83.

[0081] In this example, the air generation and / or injection module 8 further includes at least one valve or solenoid valve 87 connected to the air reservoir 85 and the nozzle 81, enabling adjustment and control of the air jet delivered to the nozzle 81, particularly to deliver a predetermined air volume (e.g., 10 ml) at a predetermined pressure (e.g., 1.5 bar). The valve 87 or solenoid valve enables the sequential release of the air jet.

[0082] Of course, any other device that can generate or produce an air jet is conceivable. Any device that can deliver air and / or spray air onto the outer surface 9b of the optical element 9 is also conceivable.

[0083] According to an alternative not shown, a motor 5 configured to cause the optical element 9 to align can be used to generate an air jet to be sprayed onto the optical element 9. F .

[0084] case Referring again to [Figure 3], the housing 6' is advantageously a sealed housing 6'. The housing 6' can be made of any suitable material known to those skilled in the art.

[0085] The housing 6' is configured to receive the optical sensor 13 and the motor 5. In particular, the housing 6' may define a recess 60 that receives both the optical sensor 13 and the motor 5.

[0086] The housing 6' can also accommodate a device 7 for transmitting motion of the rotating shaft 510 to the optical element 9. The transmission device 7 can be accommodated in the same recess 60 as the motor 5 and the optical sensor 13.

[0087] As described above, the protective device 3 may include an air-generating component, and in this case, the housing 6' may specifically receive this air-generating component in the same recess as the optical sensor 13, the motor 5, and the transmission device 7.

[0088] According to the illustrated embodiment, the recess 60 also includes a pump 83, an air reservoir 85, and a valve or solenoid valve 87. Of course, the pump 83 and the air reservoir 85 can be remote, meaning they can be arranged outside the housing 6', adjacent to the optical sensor 13.

[0089] Furthermore, the housing 6' at the rear of the motor 5 is advantageously provided with a sealing arrangement for cables or wires to pass through, so as to limit water vapor and / or other contaminants from entering the interior of the protective device 3.

[0090] Therefore, during operation, the actuator, more precisely the motor 5, rotates the first sprocket 71, which in turn rotates the second sprocket 73, which meshes with the optical element 9. Rotating the optical element 9, optionally combined with spraying fluid (such as a jet of compressed air) onto the outer surface 9b of the optical element 9, ensures that dirt is removed due to the centrifugal force experienced by the optical element. Thus, the field of view of the optical sensor 13 remains clear.

[0091] Furthermore, during the production of this protective device 3, the rotation axis A2 of the motor 5 intersects or is even perpendicular to the rotation axis A1 of the optical element 9, which allows for a reduction in the space occupied by the protective device 3 and the achievement of a very compact device 3. This is particularly advantageous for mounting the protective device on a motor vehicle 100.

Claims

1. A device (3) for an optical sensor (13) of a driver assistance system (1) for protecting a motor vehicle (100), the optical sensor (13) comprising an optical element (14), the device (3) comprising: - Optical element (9), which is configured to be positioned upstream of the optical device (14) of the optical sensor (13) and rotatably mounted about a first rotation axis (A1), and - Motor (5), the motor being configured to rotate the optical element (9), The motor (5) includes a rotor (51) configured to rotate about a second rotation axis (A2) that intersects a first rotation axis (A1) of the optical element (9); The device (3) includes at least one transmission device (7) for transmitting the motion of the rotor (51) of the motor (5) to the optical element (9). The transmission device (7) includes a first sprocket or gear (71) and a second sprocket or gear (73), the first sprocket or gear (71) being positioned such that it can rotate about a second rotation axis (A2), and the second sprocket or gear (73) being positioned to mesh with the first sprocket or gear (71) and such that it can rotate about the first rotation axis (A1); The second sprocket or gear (73) is positioned around the optical components (14) of the optical sensor (13).

2. The device (3) as claimed in claim 1, wherein, The second rotation axis (A2) of the motor (5) is substantially perpendicular to the first rotation axis (A1) of the optical element (9).

3. The device (3) as described in any of the preceding claims, wherein, The optical element (9) is configured to be arranged relative to the optical device (14) of the optical sensor (13) such that the first rotation axis (A1) of the optical element (9) is parallel to or coincides with the optical axis (15) of the optical sensor (13).

4. The device (3) of claim 1, comprising a housing (6') configured to receive the optical sensor (13) and the motor (5).

5. The device (3) as claimed in claim 1, wherein, The device (3) further includes at least one region for generating and / or spraying air onto the optical element (9). Z1 Module (8) on ) 6. The device (3) as claimed in claim 5, wherein, The air generation and / or injection module (8) includes at least one air nozzle (81).

7. The device (3) as claimed in claim 6, wherein, The air nozzle (81) is arranged such that the air nozzle jets air ( F It is sprayed onto the central region of the optical element.

8. The device (3) as described in any one of claims 5 to 7, wherein, The air generation and / or injection module (8) includes at least one air generation component selected from at least a piston, a pump (83), an air reservoir, and an impeller.

9. The device (3) as claimed in claim 6, wherein, The air generation and / or injection module (8) includes: - At least one pump (83) for generating an air jet, and - An air reservoir (85) connected to the pump (83) to store the air jet generated by the pump (83).

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