Patent Application
20250060581
This application claims priority to German Patent Application No. 10 2023 121 933.2, filed on Aug. 16, 2023, the entirety of which is incorporated herein by reference.
The disclosure refers to a camera arm adapted for an exterior camera arm system to be mounted on an exterior side of a vehicle. In particular, the camera arm comprises a passive camera cleaning component established by an inlet opening facing towards a driving direction of the vehicle, an outlet opening adapted to face a camera lens of a camera of the camera arm and an air guiding channel connecting inlet opening with outlet opening providing a cleaning air flow resulting from an interference of the air flow let out of the outlet opening and a suction effect towards the camera lens when the vehicle is driven. The disclosure further relates to a camera arm system comprising such camera arm and to a vehicle comprising such camera arm system.
Motor vehicles comprise cameras to observe the driving situation around the vehicle. These cameras are exposed to the environmental conditions around the vehicle and get dirty over time. Therefore, the cameras and must be cleaned from dirt and water regularly for reliable operation. Otherwise, the driving security might be endangered. Beside active cleaning components, also passive cleaning measures are used to clean those cameras. The latter require less component effort, since the passive components do not require moving parts or actuators and represent a cheaper solution.
Document DE 10 2019 004 778 discloses a camera system for a motor with a camera housing and a camera lens, where the camera housing has at least one air flow channel with an inlet opening for receiving airstream and an outlet opening for discharging the airstream in order to blow the camera lens and/or its field of view free of impurities. However, during driving there is a speed dependent continuous airstream around the vehicle. This driving causes the airflow exiting the outlet port and being deflected away from the camera lens being cleaned by the airstream passing the camera system on the outside. For this reason, the camera lens is not cleaned in a controlled and reliable way leading to remaining impurities of water drops on the camera lens lowering the driving security.
It is therefore desirable to provide a passive cleaning procedure enabling reliable cleaning of the camera lens even under driving conditions.
An object of the present disclosure is to provide a passive cleaning procedure enabling reliable cleaning of the camera lens even under driving conditions.
This object may be solved by a camera arm adapted for an exterior camera arm system to be mounted on an exterior side of a vehicle comprising a recess provided for receiving a camera with an outer camera lens being part of or protruding from a recess surrounding outer surface of the camera arm, wherein the camera arm comprises a passive camera cleaning component established by an inlet opening facing towards a driving direction of the vehicle when being mounted to the vehicle, an outlet opening adapted to face the camera lens of the camera when received in the recess and an air guiding channel connecting inlet opening with outlet opening to guide an air flow caused by an airstream when driving the vehicle, the outlet opening being adapted to let out the air flow across the recess surrounding outer surface in a flow direction with a main directional component being directed substantially perpendicular to the driving direction of the vehicle, where the camera arm is suitably shaped to provide a suction effect to the air flow in the opposite direction of the driving direction when driving the vehicle, where a cleaning air flow resulting from an interference of the air flow let out of the outlet opening and the provided suction effect is directed towards the camera lens of the camera being received in the recess when the vehicle is driven.
The camera arm may have any suitable shape to carry the camera and to be attachable to a vehicle. The camera arm might by attached to the vehicle side. The camera arm might be substantially a hollow body with a substantially closed outer surface. The camera arm might be made of any suitable material. The material might be plastic comprising further components inside made of any other or the same material.
The term “recess” denotes a cavity in the camera arm with a hole to the outside, where a camera can be suitably placed inside enabling to record images from the environment of the camera arm or the vehicle. The recess is surrounded by the outer surface of the camera arm, where the outer surface near the recess is denoted as recess surrounding outer surface. The camera can be placed inside the recess in such a way that the outer camera lens closes the recess to the outside in contact with the recess surrounding outer surface establishing a contiguous surface in combination with the recess surrounding outer surface. In other embodiments the camera and therefore the camera lens may protrude from the recess surrounding outer surface.
The term “camera” denotes any unit, which is capable to optically recording a scenery comprising an optical lens as an entry aperture from electromagnetic radiation from the environment of the camera and an optical path inside the camera suitable to guide the received electromagnetic radiation to a suitable sensor, where the electromagnetic radiation is converted into an electronic signal or picture, where the properties of optical lens, optical path and sensor determine the resolution of the recorded scenery, which might be displayed on the monitoring unit to a driver of a vehicle. The electromagnetic radiation received by the camera unit and converted by the sensor might be radiation of the infrared, visible and/or ultraviolet spectrum of wavelengths.
The passive camera cleaning component denotes a component of the camera arm, where a certain air flow can be directed to a target, here the camera lens. The air flow is generated without any electrical components such as pump or fan just applying a channel through the camera arm, where the air flow flows from an inlet opening to an outlet opening. Inlet and outlet opening may have any suitable shape, where the outlet opening might act as a nozzle to direct the air flow to the target. The air flow is caused by the air resistance during the travel of the vehicle resulting in an airstream flowing around the vehicle during driving. Here, the airstream also penetrates the camera arm via the air guiding channel. The higher the driving speed, the higher the speed of the air flow. However, the speed of the airflow leaving the outlet opening further depends on shape and dimensions of the air guiding channel and the location of the passive camera cleaning component within the camera arm and its alignment with respect to the driving direction. The driving direction denotes the direction, into which the vehicle moves. If the inlet opening of the passive camera cleaning component has an inlet area essentially aligned perpendicular to the driving direction, the airstream enters with maximum speed into the passive camera cleaning component and generates an air flow through the air guiding channel with maximum speed. In case of the vehicle stops, there will be no air flow or only a neglectable air flow caused by the environmental wind through the air guiding channel. The outlet opening is shaped and positioned in such a way that the air flow leaves the passive camera cleaning component in a direction suitable to clean the camera lens. The passive camera cleaning component might be made of plastic and might comprise one or more bends between inlet and outlet openings.
The flow direction of the air flow having left the outlet opening is a vector composed of a component perpendicular to the driving direction of the vehicle and parallel to the driving direction in direction to the vehicle backside. Here, the main directional component is directed perpendicular to the driving direction of the vehicle. That means that the angle between the direction of the air flow at the outlet opening and the direction perpendicular to the driving direction (the direction pointing towards the vehicle side, where the camera arm is mounted to) is less than 45 degrees. However, the camera arm is a massive acrodynamic drag with a side opposite to the airstream caused by the vehicle speed resulting a suction effect on the air on this side opposite to the airstream. The suction effect acts on the air flow after the air flow having left the outlet opening pressing the air flow more in opposite driving direction (backwards direction). The resulting air flow direction is denoted as direction of the cleaning air flow, which is directed over the lens. This cleaning air flow results from the interference of the air flow with air flow direction at the outlet opening and the provided suction effect. In order to have the cleaning air flow passing the camera lens under driving conditions, the original direction of the air flow when leaving the outlet opening being not disturbed by the driving airstream is directed to a region of the recess surrounding outer surface located between the camera lens and the front of the camera arm directed towards the driving direction. The airstream across the camera arm and the resulting suction effect presses the cleaning air flow towards the camera lens.
The camera arm might be mounted on an exterior side of the vehicle, e.g. the left and/or right side of the vehicle acting as a rear-view viewing device. The term “vehicles” denotes any means of transport that provides the driver with at least a partial rear view of traffic by means of additional visual aids, here the camera monitoring system. Vehicles might be cars, trucks, motor bikes etc.
The camera arm according to embodiments of the present disclosure enables reliable cleaning of the camera lens even under driving conditions without requiring further electrical components. The reliable cleaning can be maintained by providing a suitable shaped air flow channel and therefore is always ready for use and does not require a maintenance interval. Furthermore, the camera arm according to embodiments of the present disclosure does not produce whistling noise during driving.
In an embodiment the air flow entering the air guiding channel via the inlet opening has a first air flow direction, where the air guiding channel comprises a curvature of 45 degree or more redirecting the air flow inside the air guiding channel from the first air flow direction to a second air flow direction with which the air flow exits the outlet opening. In other embodiments the air guiding channel comprises a curvature of 60 degree or more.
In another embodiment the air guiding channel comprises one or more lamellas arranged along the air flow inside the air guiding channel dividing the air flow into two or more sub-air flows. The number of applied lamellas may depend on the size of the air guiding channel perpendicular to the direction of the air flow. There might be two lamellas inside the housing of the air guiding channel. The housing also guides the air flow through the air guiding channel. The one or more lamellas may divide the inlet opening into separate sub-openings. The lamellas help to optimize the air flow. The size of the sub-openings in relation to each other adapt the air quantity to be let into the air guiding channel. The sub-openings may have inlet areas increasing from the sub-opening with the longest distance to a vehicle side of the camera arm to the sub-opening arranged in closest distance to the vehicle side of the camera arm.
In another embodiment a cross sectional area of the air guiding channel perpendicular to the air flow decreases from the inlet opening to the outlet opening. The decreasing cross section of the air guiding channel leads to an acceleration of the air flow of up 50% faster at the outlet opening compared to the air flow speed at the inlet opening.
In another embodiment the inlet opening has a substantially round, elliptical, semicircle, triangular, polygonal, diamond, rhomboid, cross, ring, arched, and/or rectangular shape, wherein preferably a horizontal width of the inlet opening is larger than its vertical width. A, preferably rectangular, shape with a large horizontal length and a smaller vertical length enables to provide a large opening while still minimizing the wind resistance of the camera arm. The term “horizontal” denotes a direction parallel to the ground on which the vehicle is located. The term “vertical” denotes a direction perpendicular to the ground on which the vehicle is located.
In another embodiment the outlet opening is covered by an air guiding element to further shape the air flow towards the camera lens. The air guiding element can be used for fine tuning the air flow outgoing direction and air flow speed. This allows to apply the same air guiding channel design to different car versions and to different arm version. The air guiding elements might be made of plastic.
In another embodiment the air guiding element is a grille element comprising one or more ribs extending towards the recess. There might be at least one of the one or more ribs tapering towards the recess. The ribs allow dosing of the air flow and special flow profiles can be implemented. The length of the rips in direction towards the recess depends on the shape of the recess surrounding outer surface of the camera arm. The term “grille” denotes a cover covering an opening in a body of the vehicle to allow air to enter or exit.
In another embodiment the air guiding element is an air tunnel suitable shaped to guide the air flow to the camera lens, where the air flow is lifted from the recess surrounding outer surface. The air tunnel compensates the indirect influence of the main airstream around the arm, even in case of the air flow is not directed in favor of the camera by changing its local air flow. The air tunnel might be applied in case of a camera lens protruding from the recess surrounding outer surface.
In another embodiment the air guiding element is reversibly attachable to the outlet opening. The attachment might be performed by clipping and/or screwing. The attachable air guiding element allows to use the same passive camera cleaning component for different camera arms, different vehicles, different driving speeds and different cameras with different shapes of the lenses, because the air flow direction can be finetuned via the attachable air guiding element. This reduces the production costs since only a small component has to be adapted to different use cases instead of requiring different passive camera cleaning components.
In another embodiment the outlet opening has a substantially round, elliptical, semicircle, triangular, polygonal, diamond, rhomboid, cross, ring, arched, and/or rectangular shape, where a horizontal width of the outlet opening is larger than a vertical width of the substantially round, elliptical, semicircle, triangular, polygonal, diamond, rhomboid, cross, ring, arched, and/or rectangular shape. Therefore, the air flow leaving the passive camera cleaning component covers a wide area of the recess surrounding outer surface in order to completely cover and thus clean the flat lens. The term “horizontal” denotes a direction parallel to the ground on which the vehicle is located. The term “vertical” denotes a direction perpendicular to the ground on which the vehicle is located.
In another embodiment an imaginary reference line extends in perpendicular direction from the horizontal width of the rectangular shape of the outlet opening to the center of the camera lens, where a geometrical center of the, preferably substantially round, elliptical, semicircle, triangular, polygonal, diamond, rhomboid, cross, ring, arched, and/or rectangular, shape of the outlet opening is shifted along the horizontal width of the, preferably substantially round, elliptical, semicircle, triangular, polygonal, diamond, rhomboid, cross, ring, arched, and/or rectangular, shape of the outlet opening in driving direction by a distance starting from the imaginary reference line to the geometrical center being equal or larger than ¼ of the horizontal width. A camera arm having the outlet opening located according to this specification provides an optimum cleaning air flow to the camera lens when driving at a vehicle speed of 80 km/h, which is a common speed of trucks.
In another embodiment a wing guide is arranged close to the recess surrounding outer surface and being suitably shaped to block at least partly the recess surrounding outer surface from direct contact with the airstream around at least a part of the camera arm caused by driving the vehicle, and/or wherein the wing guide is substantially in the form of a wall, preferably adapted to change the direction of the air stream and reduce the pressure onto the camera lens. Here the shape of the wing guide may be either matched and synchronized with the outlet opening of the passive camera cleaning component and also matched not to influence the field of view of the camera. The wing guide, in particular in form of a substantially wall-shaped embodiment, may act as a vacuum generator in direction of the airstream towards the recess of the camera arm based on its aerodynamic effect. The generated vacuum deflects the airstream with dust or rain drop from the camera lens. The acting low pressure is generated by the airstream flowing around. This effect is normally used for airplane lifting effect on its wings according to the Bernoulli's conservation of energy law. The higher speed of the airstream caused by the wing guide leads to a force lifting up dust or rain drops from the camera lens.
In another embodiment the wing guide is suitably shaped to provide an air cushion around the outlet opening and the camera lens lifting off the airstream from the recess surrounding outer surface. In case of an air cushion between camera arm and airstream around the camera arm, the camera lens is kept free of dust or rain drop transported with the surrounding airstream. The air cushion is mostly stable above the recess surrounding surface with flow speeds below 8 m/s, mostly below 4 m/s.
In another embodiment the wing guide has a first surface directing towards the recess and a second surface directing in an opposite direction, where the wing guide has a sawtooth shape with the second surface as a slowly rising surface and the first surface as a steeply sloping surface of the sawtooth shape. This shape provides a reliable air cushion behind the wing guide covering the camera lens. With increasing of the travel speed “v” the suction effect (drag coefficient) can change. Most vehicles travel more likely on long distance with certain travel limited speed. This speed can be considered in the simulations and geometry of the wing guide can be profiled based on this the surface has precondition on the travelling direction. It can be applied on any direction perpendicular to the travel direction-up/down/lateral shape is adapted to the vehicle shape and specific to a chosen travel speed. The wing guide has no effect as the vehicle is stopped.
In another embodiment the first surface protrudes from the recess surrounding surface with optionally a height that is at least of twice as large as the height of the camera lens with which the camera lens protrudes from the recess surrounding surface. However, the height of the first surface is adapted not to influence the field of camera view. The allowable absolute height the first surface also depends on the height of the camera lens with which the camera lens protrudes from the recess surrounding surface and on the size of the camera lens.
In another embodiment the first surface protrudes in vertical direction from the recess surrounding surface. However, the first surface is not allowed to influence the field of camera view and is matched and synchronized with the outlet opening of the passive camera cleaning component.
In another embodiment the wing guide partly surrounds the recess and/or the camera lens. The partly surrounding wing guide enables precisely shaping of the lifting up effect to remove dust or rain drops from the camera as well as preventing further dust or rain drops as part of the surrounding airstream reaching the camera lens during driving the vehicle.
In another embodiment a sealing is arranged between the camera and/or camera lens and the recess surrounding outer surface of the camera arm, the sealing covering a clearance gap between the camera and/or camera lens and the recess surrounding outer surface. Due to the tolerance chain the camera and the camera arm has always a gap between. The clearance gap is required between the camera/camera lens and a lower cover of the camera arm to avoid additional stresses in the housing. Additional stresses can negatively influence the scam behavior at the overall level of the camera arm system, in particular the stitching behavior. Water leaks out of the camera arm through the clearance gap between camera/camera lens and the recess surrounding outer surface as the part of the camera arm housing around the camera/camera lens and will cover the camera lens. The sealing (or seal) provides at the same time freedom of movement and clearance parallel to the recess surrounding outer surface and eliminates water leakage from the inside of the camera arm to the outside of the camera arm to keep the camera lens free of water drops. The sealing allows mounting the camera to the recess by simply pushing the camera and/or the camera lens through the scal.
The sealing may be provided by an inserted elastic element and/or over molding of a part of the camera and/or lower cover of the camera arm. If a grommet around of the camera lens is used, this grommet may be enhanced with an additional scaling lip. The additional scaling lip may have a pre-bending (without radial force on the camera lens) to the lower cover of the camera arm to provide a more robust scaling behavior.
In another embodiment the sealing is provided as a deformation capable lip. This enables an easy filling of the clearance gap and of the mounting of the camera to the recess from the inside of the camera arm. The deformable lips are finally shaped during the mounting of the camera.
In another embodiment the sealing is applied, advantageously to the recess surrounding outer surface, by a multi-material molding technology or by reversibly attaching the scaling as a separate component, preferably onto the recess surrounding outer surface. Multi-material injection molding (MMM) is the process of molding two or more different materials into one plastic part at one time creating a single-structure component (here the camera arm or a part of the camera arm) with different regional materials. In case of two different material involved, the technique is also known as 2K molding.
In another embodiment the scaling is applied or attached to the recess surrounding outer surface, or to a side face of the camera and/or the camera lens, where the side face is directing towards the recess surrounding outer surface. The clearance gap between camera/the camera lens and the recess surrounding outer surface shall be closed. This can be done by the scaling connected either to the recess surrounding outer surface or to the camera and/or the camera lens, where the sealing lips touch the opposite surface, either the camera and/or the camera lens or the recess surrounding outer surface depending on the component, where the scaling is fixed to.
In another embodiment the sealing is made of a material suitable to avoid stiching between the camera or camera lens and the recess surrounding outer surface. Also, the geometric design of the sealing might be adapted to avoid stiching. The term “stiching” denotes a sticking of the seal to the opposite side, which can hinder or even prevent the movement of the camera in the xyz-direction. Sealing on the housing and thus the clearance requirement between the housing and camera as design premises for image stability provides a WA and NA camera stiching challenge to be solved. The provided solution gives movement freedom to the camera to avoid stiching from one perspective and gives sealing solution between the housing and the camera to block the potential water drops.
The disclosure further relates to a camera arm system comprising a camera arm according to the present disclosure and a camera with an outer lens placed in a recess of the camera arm for receiving the camera, where the outer lens being part of or protruding from a camera surrounding outer surface of the camera arm.
The disclosure further relates to a vehicle comprising one or more camera arm system according to the present disclosure.
The embodiments described above can be combined with one another as desired by the person skilled in the art within the scope of the teaching according to the disclosure, also in deviation from the claim references.
In the following, the disclosure and its embodiments are further explained with regard to the drawings.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2023 121 933.2 | Aug 2023 | DE | national |
