Camera device and heating control method for camera device

Abstract

To provide a camera device and a method for controlling heating of the camera device which enable suppression of adhesion of water droplets to the lens of the camera device exposed to the outside air.SOLUTION: The camera device comprises a lens 3 exposed to the outside air, a lens barrel 2, a first heater 41, a second heater 42 and a control unit. The lens barrel 2 has a flange 21 which covers the outer edge of the lens 3, and in which water repellent treatment is applied to the outer surface of an inner edge continuous to the lens 3. The first heater 41 heats the lens 3. The second heater 42 heats the outer surface of the flange 21. The control unit switches, on the basis of the state of the outside air and the traveling speed of a vehicle, between a first electrical continuity state in which electricity is conducted to the first heater 41 and a second electrical continuity state in which electricity is conducted to the second heater 42, in addition to the first heater 41.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a camera device mounted on, for example, a vehicle, and a heating control method for the camera device. [Background technology]

[0002] For example, a camera device mounted on a vehicle continuously captures images of the surroundings of the vehicle, such as the front and rear of the vehicle, and records the images. The camera device is attached to the inside or outside of the vehicle, but a camera device installed outside the vehicle, such as a camera that captures far-infrared wavelengths, is exposed to the external environment, such as wind and rain.

[0003] Patent Document 1 discloses a camera device in which a tapered inclined portion is provided on the outer edge of the lens exposed to the outside air. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-086123 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the camera device described in Patent Document 1, when water droplets adhere to the lens exposed to the outside air, a flow velocity vector is generated by the vehicle's movement, etc., and the water droplets are swept to the outside of the lens. However, the viscosity of water droplets adhering to the lens increases when snow or rain becomes cold, making it difficult for them to flow off the lens. In addition, water that has flowed off the lens may accumulate in the flange and freeze.

[0006] The present invention has been made in consideration of the above circumstances, and has as its object to provide a camera device and a heating control method for a camera device that can prevent water droplets from adhering to a lens exposed to the outside air. [Means for solving the problem]

[0007] A camera device according to one embodiment of the present invention is a camera device used in a vehicle, and includes: a lens exposed to the outside air; a lens barrel having a flange covering the outer edge of the lens and having an inner edge connected to the lens and having an outer surface with a water-repellent treatment applied thereto; a first heater for heating the lens; a second heater for heating the outer surface of the flange; and a control unit that switches between a first power supply state in which current is applied to the first heater and a second power supply state in which current is applied to the second heater in addition to the first heater based on the outside air conditions and the traveling speed of the vehicle.

[0008] Another aspect of the present invention is a heating control method for a camera device for a vehicle in which a flange is provided on a lens barrel covering an outer edge of a lens exposed to the outside air and having an outer surface of an inner edge connected to the lens treated with a water-repellent treatment, the method including an information acquisition step of acquiring outside air conditions and a driving speed of the vehicle, and a switching step of switching between a first current supply state in which current is applied to a first heater that heats the lens and a second current supply state in which current is applied to a second heater that heats the outer surface of the flange in addition to the first heater, based on the outside air conditions and driving speed acquired by the information acquisition step. Effect of the Invention

[0009] According to the present invention, it is possible to prevent water droplets from adhering to a lens exposed to the outside air. [Brief description of the drawings]

[0010] [Figure 1] 1 is a perspective view showing an external appearance of a camera device according to an embodiment. [Diagram 2] FIG. 2 is a cross-sectional view of the front end portion of the camera device. [Diagram 3] FIG. [Figure 4] FIG. 2 is a block diagram showing a configuration of the camera device. [Diagram 5] 5 is a flowchart showing a procedure for controlling power supply to each heater in the camera device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present invention will be described below based on a preferred embodiment with reference to Figures 1 to 5. The same or equivalent components and members shown in each drawing are given the same reference numerals, and duplicated explanations will be omitted as appropriate. Furthermore, the dimensions of the members in each drawing are enlarged or reduced as appropriate for ease of understanding. Furthermore, some of the members that are not important for explaining the embodiment are omitted in each drawing.

[0012] (Embodiment) FIG. 1 is a perspective view showing the appearance of a camera device 100 according to an embodiment. The camera device 100 includes a camera body 1, a lens barrel 2, a lens 3, and the like. The camera body 1 is box-shaped with a hole leading to the inside of the lens barrel 2, and contains an image sensor, a filter, and the like (not shown) inside. The lens barrel 2 is cylindrical and supports an optical system arranged inside, and a lens 3 is fitted into an opening 2a on the front side. The lens barrel 2 has a frame 20 for holding the lens 3. The lens 3 is, for example, an aspheric lens, but is not limited to this, and may be a spherical lens, etc. In addition, the camera device 100 is, for example, a far-infrared camera, but is not limited to this, and may be a visible light imaging camera, etc. It should be noted that the camera body 1 itself may be considered to be a part of the lens barrel 2.

[0013] 2 is a cross-sectional view of the front end portion of the camera device 100. When the camera device 100 is attached to a vehicle, the front surface side of the lens 3 is exposed to the outside air and is exposed to the external environment such as wind and rain. The outer edge portion of the front surface side of the lens 3 exposed to the outside air is covered by a flange 21 of a frame portion 20 of the lens barrel 2. The lens barrel 2 is provided with the frame portion 20 that holds the lens 3 by fitting it into the inside of an opening hole on the front end side, but the frame portion 20 and the lens barrel 2 may be formed integrally.

[0014] The frame 20 of the lens barrel 2 has a flange 21 that covers the outer edge of the front surface of the lens 3, and a light-shielding portion 23 is formed on the inner periphery of the inner edge 22. The light-shielding portion 23 is tapered in the optical axis direction, and the diameter increases toward the front end. The light-shielding portion 23 functions to block infrared rays or light rays from angles larger than the taper angle.

[0015] An inclined portion 24 is formed on the inner edge 22 of the flange 21, continuing from the outer periphery of the light-shielding portion 23. The inclined portion 24 is tapered so that its diameter increases toward the front end. As shown in FIG. 2, the taper angle A of the inclined portion 24 is larger than the taper angle of the light-shielding portion 23, and more specifically, is set to 120 degrees or more. In addition, the taper angle A of the inclined portion 24 is preferably set to 160 degrees or less.

[0016] The flange 21 has a front end face 25 that is continuous with the outer periphery of the inclined portion 24 and extends outward. The thickness t of the flange 21 at the front end face 25 is set so as to have sufficient strength and rigidity to hold the lens 3. The thickness of the flange 21 at the light-shielding portion 23 and the inclined portion 24 is thinner than the thickness t of the front end face 25. If the thicknesses at the light-shielding portion 23, the inclined portion 24 and the front end face 25 are thin, the rigidity may decrease, causing deformation, or the strength may decrease, causing cracks, and further manufacturability may deteriorate.

[0017] 2 is formed almost at the front end of the lens barrel 2, it may be formed at a position recessed toward the camera body 1, or conversely, it may be formed at a position protruding forward. In addition, the connection between the light shielding portion 23 and the inclined portion 24, and the connection between the inclined portion 24 and the front end surface 25 may have an angle or may be smoothly rounded.

[0018] The lens 3 has a concave surface portion 3a, which is concave toward the front on the surface side exposed to the outside air, inside the light-shielding portion 23 that corresponds to the outer edge. The lens 3 has a convex surface portion 3b, which is convex toward the front, on the inside continuous with the concave surface portion 3a. The lens 3 shown in FIG. 2 is formed as an aspheric lens. Also, as described above, the lens 3 may be a spherical lens or the like, in which case the concave surface portion 3a may not be formed.

[0019] 3 is a cross-sectional view of flange 21. Light-shielding portion 23, inclined portion 24, and front end face 25 have surface treatment film 26 formed on the surfaces exposed to the outside air. Surface treatment film 26 may also be formed on the front end face of lens barrel 2 that is continuous with the outer edge of front end face 25. Flange 21 is made of aluminum, and surface treatment film 26 is formed by black anodizing.

[0020] When water droplets adhere to the light-shielding portion 23, the inclined portion 24, and the front end face 25 due to rainfall, the adhered water droplets act as resistance, slowing down the flow speed of the wind flowing from the center of the lens 3 to the outside as indicated by the arrow P in Fig. 3. The surface treatment film 26 is formed so that the water droplets adhering to the light-shielding portion 23, the inclined portion 24, and the front end face 25 can easily flow outward and be discharged, and do not accumulate.

[0021] In anodizing, an oxide coating is produced with a porous layer of fine pores formed by anodizing. The porous layer provides adhesion for adhesion, adhesion, and painting. A coating colored in silver, bronze, black, white, etc. is produced that penetrates the porous layer, making the coating less likely to peel off.

[0022] Furthermore, by depositing a resin coating on the surface of the porous layer using a method such as electrodeposition coating, the surface can be made glossy, matte, white, etc. Furthermore, a blasting treatment may be performed before the anodizing treatment, in which the surface is roughened by blasting with small particles.

[0023] 2, a first heater 41 and a second heater 42 are provided on the lens 3 and the frame 20. The first heater 41 is ring-shaped and is attached to the outer edge of the back surface of the lens 3. The second heater 42 is also ring-shaped and is attached to the outer circumferential surface of the frame 20 inside the lens barrel 2.

[0024] The first heater 41 warms the lens 3 by heating, reducing the viscosity of water droplets on the surface exposed to the outside air and preventing the water droplets from freezing. The first heater 41 warms the lens 3 by heating the outer periphery of the lens 3. The second heater 42 warms the lens 3 and the frame 20 by heating, reducing the viscosity of water droplets on the surface of the lens 3 and the outer surface of the flange 21 of the frame 20 and preventing the water droplets from freezing.

[0025] 4 is a block diagram showing the configuration of camera device 100. Camera device 100 includes an imaging section 5 and a control section 6. Imaging section 5 has an imaging element 51, a first heater 41, and a second heater 42. Imaging element 51 is formed of a detector such as a CCD, and detects light that has entered camera body 1 through lens 3. First heater 41 and second heater 42 heat lens 3 and frame section 20 as described above.

[0026] The control unit 6 has an imaging control unit 61, a heater control unit 62, and an information acquisition unit 63. The imaging control unit 61 controls the imaging element 51 to capture an image of the outside of the vehicle. The heater control unit 62 controls the on / off of the electricity supply to the first heater 41 and the second heater 42. The information acquisition unit 63 acquires information on the outside air condition and the traveling speed of the vehicle. The outside air condition is, for example, the weather (sunny, rain, fog, snow, sleet, etc.), the outside temperature, etc.

[0027] The information acquisition unit 63 acquires the state of the outside air from a temperature sensor (not shown) provided in the vehicle. The information acquisition unit 63 also acquires information on the state of the outside air, such as weather, via a communication device (not shown). Furthermore, the information acquisition unit 63 acquires information indicating the traveling speed of the vehicle from a vehicle speed sensor (not shown) or the like.

[0028] The heater control unit 62 performs control to switch between a first power supply state in which current is supplied to the first heater 41 and a second power supply state in which current is supplied to the second heater 42 in addition to the first heater 41, based on the outside air conditions and driving speed acquired by the information acquisition unit 63.

[0029] Next, the operation of the camera device 100 will be described based on the power supply control for each heater. Fig. 5 is a flow chart showing the procedure of the power supply control for each heater in the camera device 100. The information acquisition unit 63 of the control unit 6 acquires information on the outside air condition and the driving speed (S1). The heater control unit 62 judges whether the weather is rainy or foggy based on the information on the outside air condition (S2). The judgment in step S2, in other words, judges that the state is such that water droplets adhere to the surface of the lens 3 due to rainfall or fog.

[0030] In step S2, when it is determined that the weather is rainy or foggy (S2: YES), the heater control unit 62 determines whether or not there is a possibility that water droplets will freeze due to the vehicle's travel based on the information on the outside air temperature and the travel speed (S3). In other words, the determination in step S3 determines that the water droplets attached to the surface of the lens 3 will not freeze or will not freeze due to the influence of the outside air temperature alone, but that the lens 3 and the like will be exposed to wind as the vehicle travels, resulting in a state in which the water droplets will actually freeze or will freeze. The determination in step S3 is determined by estimating from the outside air temperature and the travel speed of the vehicle. In step S3, when it is determined that there is no possibility that water droplets will freeze due to the vehicle's travel (S3: NO), the heater control unit 62 controls to switch to the first power supply state (S4) and ends the process. As described above, the first power supply state is a state in which the power supply to the first heater 41 is turned on.

[0031] If it is determined in step S2 that the weather is not rainy or foggy (S2: NO), the heater control unit 62 determines whether the weather is snowy or sleet (S5). In other words, the determination in step S5 determines that the weather is in a state in which frozen or potentially frozen water droplets adhere to the surface of the lens 3 due to snow or sleet. If it is determined in step S5 that the weather is snowy or sleet (S5: YES), the heater control unit 62 controls to switch to the second power supply state (S4) and ends the process. As described above, the second power supply state is a state in which power is supplied to both the first heater 41 and the second heater 42.

[0032] In step S5, if it is determined that the weather is not snow or sleet (S5: NO), the heater control unit 62 determines that the weather is, for example, sunny, turns off the power to the first heater 41 and the second heater 42, and ends the processing.

[0033] Furthermore, in step S3, if it is determined that there is a possibility that water droplets will freeze due to the vehicle's travel (S3: YES), the heater control unit 62 controls switching to the second power supply state (S4) and ends the process. By appropriately repeating the processes from steps S1 to S6 described above, the control unit 6 executes power supply control of the heater of the camera device 100 based on information on the ever-changing outside air condition and travel speed. Note that the switching step in the present invention corresponds to the processes from steps S2 to S6 described above.

[0034] The camera device 100 can prevent water droplets from adhering to the lens 3 by executing switching control to turn on and off the power supply to the first heater 41 and the second heater 42 based on information on the outside air condition and the traveling speed.

[0035] The control unit 6 reduces the viscosity of water droplets adhering to the surface of the lens 3 by heating the first heater 41, thereby suppressing the adhesion of water droplets to the lens 3. In addition, the control unit 6 melts snow or ice adhering to the surface of the lens 3 by heating the first heater 41 and the second heater 42, thereby suppressing the adhesion of water droplets to the lens 3.

[0036] By acquiring information on weather and outside temperature as outside air conditions, the camera device 100 can predict whether snow or ice will fall on the lens 3 and can determine whether water droplets will freeze on the surface of the lens 3.

[0037] When the weather is rainy or foggy and the information on the outside temperature and the driving speed indicates that the water droplets will not freeze, the control unit 6 of the camera device 100 controls the power supply to the first heater 41 to a first power supply state in which the power supply to the first heater 41 is turned on. When the power supply to the first heater 41 is turned on in the camera device 100, the lens 3 is warmed, the viscosity of the water droplets falling on the surface of the lens 3 is reduced, and the water droplets are easily removed, thereby suppressing the adhesion of the water droplets to the lens 3.

[0038] When the weather is rainy or foggy and there is a possibility that water droplets will freeze based on information on the outside temperature and the driving speed, the control unit 6 controls the power supply to the first heater 41 and the second heater 42 to a second power supply state in which the power supply is on. When the weather is snowy or sleet, the control unit 6 controls the power supply to the first heater 41 and the second heater 42 to a second power supply state in which the power supply is on. When the power supply to the first heater 41 and the second heater 42 is on, the camera device 100 warms the lens 3 and the frame 20, suppressing the freezing of water droplets that have fallen on the outer surfaces of the flange 21 of the lens 3 and the frame 20, and melts the snow and ice, suppressing the adhesion of water droplets to the lens 3.

[0039] Next, features of the camera device 100 and the heating control method for the camera device 100 according to the above embodiment will be described. The camera device 100 according to the embodiment includes a lens 3 exposed to the outside air, a barrel 2, a first heater 41, a second heater 42, and a control unit 6. The barrel 2 covers the outer edge of the lens 3 and has a flange 21 with a water-repellent treatment applied to the outer surface of the inner edge connected to the lens 3. The first heater 41 heats the lens 3. The second heater 42 heats the outer surface of the flange 21. The control unit 6 switches between a first current supply state in which the first heater 41 is energized and a second current supply state in which the second heater 42 is energized in addition to the first heater 41, based on the outside air condition and the running speed of the vehicle. This allows the camera device 100 to suppress adhesion of water droplets to the lens 3.

[0040] Furthermore, the control unit 6 sets the camera device 100 to the first current-carrying state when water droplets are adhering to the lens 3 based on the outside air condition and the traveling speed of the vehicle, and sets the camera device 100 to the second current-carrying state when water droplets are freezing on the outer surface of the flange 21. This enables the camera device 100 to prevent water droplets on the outer surface of the flange 21 from freezing, and to prevent water droplets from adhering to the lens 3.

[0041] The control unit 6 also acquires information on weather and outside temperature as the state of the air outside the vehicle, which enables the camera device 100 to predict whether snow or ice will fall on the lens 3 and to determine whether water droplets will freeze on the surface of the lens 3.

[0042] Furthermore, the control unit 6 controls the first heater 41 to heat so as to reduce the viscosity of water droplets adhering to the surface of the lens 3, and controls the second heater 42 to heat so as to melt snow or ice adhering to the surface of the lens 3. In this way, the camera device 100 melts the snow or ice adhering to the surface of the lens 3, thereby suppressing the adhesion of water droplets to the lens 3.

[0043] The heating control method is a heating control method for a camera device 100 for a vehicle in which a flange 21 is provided on a lens barrel 2, the flange 21 covering the outer edge of the lens 3 exposed to the outside air and having an outer surface of an inner edge connected to the lens 3 treated with a water repellent treatment, and includes an information acquisition step and a switching step. The information acquisition step acquires the outside air condition and the traveling speed of the vehicle. The switching step switches between a first current supply state in which electricity is supplied to a first heater 41 that heats the lens 3 and a second current supply state in which electricity is supplied to a second heater 42 that heats the outer surface of the flange 21 in addition to the first heater 41, based on the outside air condition and the traveling speed acquired in the information acquisition step. According to this method, adhesion of water droplets to the lens 3 of the camera device 100 can be suppressed.

[0044] The above description is based on the embodiments of the present invention. These embodiments are merely examples, and it will be understood by those skilled in the art that various modifications and changes are possible within the scope of the claims of the present invention, and that such modifications and changes are also within the scope of the claims of the present invention. Therefore, the descriptions and drawings in this specification should be treated as illustrative rather than restrictive. [Explanation of symbols]

[0045] 2 lens barrel, 21 flange, 3 lens, 41 first heater, 42 second heater, 6 control unit, 100 camera equipment.

Claims

1. A camera device for use in a vehicle, comprising: Lenses exposed to the outside air, a lens barrel having a flange covering an outer edge of the lens and having an inner edge connected to the lens and having an outer surface treated with a water repellent treatment; a first heater for heating the lens; a second heater for heating the outer surface of the flange; a control unit that switches between a first current supply state in which current is supplied to the first heater when water droplets are attached to the lens and a second current supply state in which current is supplied to the second heater in addition to the first heater when water droplets on the outer surface of the flange are frozen, based on an outside air condition and a traveling speed of the vehicle; Equipped with camera equipment.

2. The camera device according to claim 1 , wherein the control unit acquires information on weather and outside temperature as the state of the outside air of the vehicle.

3. 3. The camera device according to claim 1, wherein the control unit heats the first heater so as to reduce a viscosity of water droplets adhering to the surface of the lens, and heats the second heater so as to melt snow or ice adhering to the surface of the lens.

4. A method for controlling heating of a camera device for a vehicle, the camera device having a lens barrel provided with a flange covering an outer edge of a lens exposed to the outside air and having an inner edge connected to the lens and having an outer surface treated with a water repellent treatment, comprising the steps of: an information acquisition step of acquiring an outside air condition and a running speed of the vehicle; a switching step of switching between a first current supply state in which current is supplied to a first heater that heats the lens when water droplets are attached to the lens, and a second current supply state in which current is supplied to a second heater that heats the outer surface of the flange in addition to the first heater when water droplets on the outer surface of the flange are frozen, based on the outside air condition and the traveling speed acquired in the information acquisition step; A heating control method for a camera device comprising:

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