Lens device

Abstract

To provide a lens device which offers improved performance in removing fogginess of a cover member facing a lens.SOLUTION: A lens device 10 is provided, comprising a lens 14, a light-transmissive cover member 20 provided to face the lens 14, and a pump 30 capable of forming an air intake path between the lens 14 and the cover member 20.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a lens device. [Background technology]

[0002] Foreign matter adhesion prevention devices that are attached to a camera body having an externally exposed imaging surface and prevent foreign matter from adhering to the imaging surface have been known for some time (see, for example, Patent Document 1). This foreign matter adhesion prevention device has a cover with a cover member that covers the imaging surface, and a nozzle that sprays a fluid toward the outer surface of the cover member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-022451 Summary of the Invention [Problem to be solved by the invention]

[0004] However, there is still room for improvement in the structure for improving the performance of removing fogging that occurs on the cover member facing the lens (shortening the time required for removal).

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a lens device that can improve the performance of removing fogging that occurs on a cover member that faces the lens. [Means for solving the problem]

[0006] In order to achieve the above object, a lens device of a first aspect according to the present invention comprises a lens, a cover member that is disposed opposite the lens and is capable of transmitting light, and a pump that is capable of forming an intake path between the lens and the cover member.

[0007] According to the first aspect of the invention, an intake path is formed by a pump between the lens and the cover member provided opposite the lens, thereby improving the ability to remove fogging that occurs on the cover member opposite the lens.

[0008] Furthermore, a second aspect of the lens device according to the present invention is a lens device according to the first aspect, configured such that the air exhausted from the pump is sprayed toward the surface of the cover member opposite the lens.

[0009] According to the second aspect of the invention, the air exhausted from the pump is sprayed toward the surface of the cover member opposite the lens, thereby cleaning both sides of the cover member and improving the ability to remove fogging that occurs on both sides.

[0010] A lens device according to a third aspect of the present invention is the lens device according to the first or second aspect, wherein a filter is provided in the intake path, and a cleaning path for the filter is formed.

[0011] According to the third aspect of the invention, a filter is provided in the intake path and a cleaning path is formed for the filter, which reduces clogging of the filter and enables stable and continuous pump performance to be maintained.

[0012] A lens device according to a fourth aspect of the present invention is the lens device according to the third aspect, wherein a switching valve for switching to the cleaning path is provided in the exhaust path from the pump.

[0013] According to the fourth aspect of the invention, a switching valve that switches to a cleaning path for the filter is provided in the exhaust path from the pump, so that clogging of the filter is efficiently alleviated with a simple configuration that makes effective use of the exhaust path.

[0014] A lens device according to a fifth aspect of the present invention is the lens device according to the third or fourth aspect, wherein the filter is provided in an intake tube that constitutes the intake path.

[0015] According to the fifth aspect of the invention, a filter is provided in the intake tube that constitutes the intake path. This makes it possible to accommodate the lens device, excluding the intake tube, in the housing. This means that the lens device, excluding the intake tube, can be sealed, ensuring the ability to prevent foreign matter (including water) from entering the lens device.

[0016] A sixth aspect of the lens device according to the present invention is the lens device of the first or second aspect, wherein the lens is housed in a housing, and a filter is provided in an intake hole of the housing.

[0017] According to the sixth aspect of the invention, a filter is provided in the air intake hole of the housing that houses the lens. This eliminates the need for an air intake tube that constitutes the air intake path, simplifying the structure of the air intake path compared to when an air intake tube is provided.

[0018] Furthermore, a seventh aspect of the lens device according to the present invention is a lens device according to any one of the first to sixth aspects, wherein the intake path is a path through which air flows from one diagonal position of the cover member to the other.

[0019] According to the seventh aspect of the invention, the intake path is a path that flows from one diagonal corner of the cover member to the other, which more effectively improves the ability to remove fogging that occurs on the cover member facing the lens.

[0020] A lens device according to an eighth aspect of the present invention is the lens device according to any one of the first to seventh aspects, further comprising a heating device that heats the lens or the cover member.

[0021] According to the eighth aspect of the invention, a heating device is provided to heat the lens or the cover member, which more effectively improves the ability to remove fogging that occurs on the cover member facing the lens.

[0022] A lens device according to a ninth aspect of the present invention is the lens device according to any one of the first to eighth aspects, wherein an intake hole is formed upstream in the extrusion direction of the piston of the pump.

[0023] According to the ninth aspect of the invention, the intake hole is located upstream in the extrusion direction of the pump piston, so that the intake air is quickly pushed out, reducing the loss of air supply.

[0024] A lens device according to a tenth aspect of the present invention is the lens device according to any one of the first to eighth aspects, wherein an intake hole is formed downstream in the extrusion direction of the piston of the pump.

[0025] According to the tenth aspect of the invention, the intake hole is located downstream in the extrusion direction of the pump piston, so that the intake air is pushed out more quickly, thereby more effectively reducing the loss of air supply. [Effects of the Invention]

[0026] As described above, according to the present invention, it is possible to improve the performance of removing fogging that occurs on the cover member facing the lens. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic perspective view showing the configuration of a lens device according to a first embodiment. [Figure 2] 1 is a schematic cross-sectional view showing the configuration of a lens device according to a first embodiment. [Figure 3] 3 is a schematic rear view showing the positional relationship between an intake hole and an exhaust hole of the lens device according to the first embodiment. FIG. [Figure 4] FIG. 10 is a schematic cross-sectional view showing the configuration of a lens device according to a second embodiment. [Figure 5] FIG. 10 is a schematic cross-sectional view showing the configuration of a lens device according to a third embodiment. [Figure 6] FIG. 10 is a schematic cross-sectional view showing the configuration of a lens device according to a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. For ease of explanation, the arrow UP shown in each drawing indicates the upward direction of the lens device, the arrow FR indicates the forward direction of the lens device, and the arrow RH indicates the rightward direction of the lens device. Therefore, in the following description, unless otherwise specified, when up / down, front / rear, and left / right directions are mentioned, they refer to up / down in the up / down direction of the lens device, front / rear in the front / rear direction of the lens device, and left / right in the left / right direction of the lens device.

[0029] First Embodiment First, a first embodiment will be described. A lens device 10 according to the first embodiment is mounted, as an example, on a vehicle (not shown). As shown in FIGS. 1 and 2, the lens device 10 includes a camera 12 having a lens 14, and the camera 12 is housed inside a hollow rectangular parallelepiped housing 16. The front end of the housing 16 is closed by a transparent cover glass 20, which is an example of a cover member that protects the lens 14 of the camera 12, and the lens 14 provided at the front end of the camera 12 and a central portion of the back surface of the cover glass 20 face each other in the front-to-rear direction.

[0030] As shown in Fig. 3, a rear wall 18 is provided at the rear end of the housing 16, and an intake hole 18A and an exhaust hole 18B are formed at diagonal positions of the rear wall 18 (at one corner on the upper side in the left-right direction and at the other corner on the lower side in the left-right direction). As shown in Figs. 1 and 2, one end of an intake tube 22 that forms an intake path is connected to the intake hole 18A, and one end of an exhaust tube 24 that forms an exhaust path is connected to the exhaust hole 18B. This forms an intake path through which air flows from one diagonal corner of the cover glass 20 to the other.

[0031] The other end of the intake tube 22 is open to the atmosphere via a filter 40. Meanwhile, the other end of the exhaust tube 24 is connected to the pump 30. Specifically, an intake hole 34 is formed on the upstream side of the extrusion direction of the piston 32 of the pump 30, and the other end of the exhaust tube 24 is connected to the intake hole 34. An exhaust hole 36 is formed at the downstream end of the pump 30 in the extrusion direction, and one end of the supply tube 26, which forms an exhaust path together with the exhaust tube 24, is connected to the exhaust hole 36.

[0032] The other end of supply tube 26 is configured as outlet 26A formed in the shape of a slit with the longitudinal direction in the left-right direction, and outlet 26A is positioned so as to be able to blow air onto the surface of cover glass 20. More specifically, a flat, annular heater 42, which is an example of a heating device, is positioned opposite a radially outer portion of the surface of cover glass 20 (a range that does not interfere with imaging by camera 12), and outlet 26A of supply tube 26 is able to blow air at a predetermined wind pressure onto the surface of cover glass 20 radially inward of heater 42.

[0033] This allows the surface of cover glass 20 to be cleaned by air (dust and the like are removed). Note that, in the case of specifications in which heater 42 is always operated (when warm air flows through housing 16), it is preferable to form intake hole 18A in a corner on one side in the left-right direction on the lower side of rear wall 18, and exhaust hole 18B in a corner on the other side in the left-right direction on the upper side of rear wall 18, instead of the positions shown in Fig. 3.

[0034] A switching valve 38 for switching the air flow path is provided midway through the supply tube 26, and one end of a cleaning tube 28 that constitutes a cleaning path is connected to the switching valve 38. The other end of the cleaning tube 28 is positioned so that air can be blown toward the inner surface of the filter 40.

[0035] That is, the other end of the intake tube 22 and the other end of the cleaning tube 28 are integrally connected, and the filter 40 is disposed at the integrally connected portion. Therefore, the air sent from the exhaust hole 36 of the pump 30 to the supply tube 26 is sprayed from the nozzle 26A formed at the other end of the supply tube 26 or from the other end of the cleaning tube 28, depending on the switching operation of the switching valve 38.

[0036] The switching valve 38 may be configured to be switched by a user's switch operation (manual valve), or may be configured to be electrically connected to a control device (not shown) together with a sensor (not shown) that detects clogging of the filter 40 at or above a threshold, and to be automatically switched when the sensor detects clogging at or above the threshold (solenoid valve). Clogging of the filter 40 at or above the threshold can be detected by a change in the current value when the pump 30 is operated, etc.

[0037] 2, most of the lens device 10, except for the connection between the other end of the intake tube 22 where the filter 40 is arranged and the other end of the cleaning tube 28, and the front end of the casing 16 (the surface of the cover glass 20), is housed in a housing 44. The housing 44 is supported by a support member 46 so as to be rotatable about its axis in the vertical direction, and is configured to be airtight.

[0038] Next, the operation of the lens device 10 according to the first embodiment configured as above will be described.

[0039] When the piston 32 of the pump 30 operates, an air intake path is forcibly formed in the space behind the cover glass 20 within the housing 16. That is, when the piston 32 moves downstream in the extrusion direction, negative pressure is created on the upstream side of the piston 32 within the pump 30 in the extrusion direction. As a result, air that passes through the filter 40 from the outer surface side to the inner surface side of the filter 40 passes through the intake tube 22 and is drawn into the housing 16 from the intake hole 18A, and the air drawn into the housing 16 is drawn into the pump 30 upstream in the extrusion direction of the piston 32 from the exhaust hole 18B via the exhaust tube 24.

[0040] This forcibly forms an air intake path in the space behind the cover glass 20 within the housing 16. Specifically, an airflow is generated between the lens 14 of the camera 12 and the back surface of the cover glass 20, which is provided opposite the lens 14, flowing from one diagonal position on the back surface to the other. This improves the ability to remove fogging that occurs on the back surface of the cover glass 20 opposite the lens 14. In other words, the time required to remove fogging can be shortened, and the fogging can be removed efficiently.

[0041] Moreover, because the airflow flows from one diagonal position to the other on the rear surface of the cover glass 20, it is possible to more effectively improve the performance of removing fogging that occurs on the rear surface of the cover glass 20 that faces the lens 14. In addition, the lens device 10 is provided with a heater 42 that heats the cover glass 20. Therefore, it is possible to more effectively improve the performance of removing fogging that occurs on the rear surface of the cover glass 20 that faces the lens 14.

[0042] Furthermore, the air heated by the heater 42 can be sent to the supply tube 26 via the exhaust tube 24 and the pump 30, and can be blown onto the surface of the cover glass 20 from the outlet 26A formed at the other end of the supply tube 26. Therefore, the surface of the cover glass 20 can be cleaned with air (to remove dust and the like), and the performance of removing fogging that occurs on the surface of the cover glass 20 as well as the back surface of the cover glass 20 facing the lens 14 can be more effectively improved.

[0043] Furthermore, in the pump 30 of this lens device 10, an intake hole 34 to which the other end of the exhaust tube 24 is connected is formed upstream in the extrusion direction of the piston 32. Therefore, air taken in through the intake hole 34 can be quickly pushed out by the piston 32, thereby reducing air supply loss.

[0044] Furthermore, in this lens device 10, a cleaning path is formed for the filter 40, which is provided at the other end of the intake tube 22 that constitutes the intake path. Specifically, the other end of the cleaning tube 28 that constitutes the cleaning path is positioned so that air can be blown toward the inner surface of the filter 40. This makes it possible to effectively alleviate clogging of the filter 40, and to maintain stable and continuous pump performance.

[0045] A switching valve 38 for switching to the cleaning tube 28 (cleaning path) is provided midway through the supply tube 26 (exhaust path), and by switching the switching valve 38, the air flowing through the supply tube 26 is blown against the inner surface of the filter 40. In other words, the air flowing through the supply tube 26 (exhaust path) is used effectively.

[0046] Therefore, compared to when the flow path for air blown onto the inner surface of the filter 40 is provided separately and independently from the cleaning tube 28 (cleaning path) connected to the supply tube 26 (exhaust path) via the switching valve 38, clogging of the filter 40 can be improved efficiently with a simple configuration.

[0047] Furthermore, since the filter 40 is provided directly at the other end of the intake tube 22, more specifically, at the connection between the other end of the intake tube 22 and the other end of the cleaning tube 28, most of the lens device 10 except for the connection and the front end of the casing 16 (the surface of the cover glass 20) can be housed in a sealed state within the housing 44. This ensures that foreign matter (including water) can be prevented from entering the lens device 10 (inside the housing 44).

[0048] Second Embodiment Next, a second embodiment will be described. Note that the same reference numerals are used to designate parts equivalent to those in the first embodiment, and detailed descriptions (including common functions) will be omitted as appropriate.

[0049] 4, the second embodiment differs from the first embodiment only in that the other end of the cleaning tube 28 constituting the cleaning path is arranged on the outer surface side of the filter 40 so as to be able to blow air in a direction intersecting (perpendicular to) the intake direction (extension direction of the intake tube 22). Even with this configuration, clogging of the filter 40 can be effectively alleviated, and stable and continuous pump performance can be maintained.

[0050] <Third embodiment> Next, a third embodiment will be described. Note that the same reference numerals are used to designate parts equivalent to those in the first embodiment, and detailed descriptions (including common functions) will be omitted as appropriate.

[0051] 5, the third embodiment differs from the first embodiment in that an intake hole 35 is formed downstream in the extrusion direction of the piston 32 of the pump 30, and the other end of the exhaust tube 24 is connected to the intake hole 35. With this configuration, the air taken in through the intake hole 35 can be pushed out more quickly by the piston 32, thereby more effectively reducing air supply loss.

[0052] <Fourth embodiment> Finally, a fourth embodiment will be described. Note that the same reference numerals are used to designate parts equivalent to those in the first embodiment, and detailed descriptions (including common functions) will be omitted as appropriate.

[0053] 6, the fourth embodiment differs from the first embodiment only in that the intake tube 22 is eliminated and a filter 40 is provided directly on the inner surface of the intake hole 18A in the rear wall 18 of the housing 16 so as to block the intake hole 18A. With this configuration, the intake tube 22 that constitutes the intake path is no longer necessary, and the configuration of the intake path can be simplified compared to when the intake tube 22 is provided. In the fourth embodiment, it is necessary that the housing 44 is not sealed, in other words, that it is configured to allow only air to enter.

[0054] The lens device 10 according to this embodiment has been described above with reference to the drawings. However, the lens device 10 according to this embodiment is not limited to the one shown in the drawings, and the design can be modified as appropriate within the scope of the gist of the present invention.

[0055] For example, the filter 40 in the first embodiment may be indirectly provided at the connection between the other end of the intake tube 22 and the other end of the cleaning tube 28. The third embodiment may be applied to the second embodiment, and the third embodiment may be applied to the fourth embodiment. In the fourth embodiment, the housing 44 and the support member 46 may not be provided.

[0056] Furthermore, lens 14 is not limited to the lens of camera 12, but may be a lens of a sensor (not shown) or the like. In other words, a sensor or the like may be housed within housing 16, rather than camera 12. Furthermore, the cover member is not limited to transparent cover glass 20, but may be a transparent resin plate made of, for example, acrylic resin or polycarbonate resin. Furthermore, the cover member is not limited to being completely transparent, and may be one that is not completely transparent, for example, one that has a color filter, as long as it is capable of transmitting light.

[0057] Furthermore, the heating device is not limited to the heater 42, and may be, for example, a device built into the camera 12 or the lens 14 (a device that can raise the temperature of the lens 14) as long as it is configured to raise the temperature of the cover glass 20. Furthermore, if the heating device is, for example, a transparent conductive film, the heating device may be provided within the imaging range of the camera 12 or the detection range of a sensor, etc. Furthermore, the lens device 10 according to this embodiment is not limited to being mounted on a vehicle. [Explanation of symbols]

[0058] 10 Lens device, 14 Lens, 16 Housing, 18A Air intake port, 20 Cover glass (cover member), 22 Air intake tube, 30 Pump, 34 Air intake port, 35 Air intake port, 38 Switching valve, 40 Filter, 42 Heater (heating device)

Claims

1. Lenses and a cover member that is disposed opposite the lens and is capable of transmitting light; a pump capable of forming an intake path between the lens and the cover member; A lens device comprising:

2. 2. The lens device according to claim 1, wherein the air exhausted from the pump is sprayed toward a surface of the cover member opposite to the lens.

3. 2. The lens device according to claim 1, wherein a filter is provided in the air intake path, and a cleaning path for the filter is formed.

4. 4. The lens device according to claim 3, wherein a switching valve for switching the exhaust path from the pump to the cleaning path is provided in the exhaust path from the pump.

5. The lens device according to claim 3 , wherein the filter is provided in an intake tube that constitutes the intake path.

6. The lens is housed in a housing, 2. The lens device according to claim 1, wherein a filter is provided in the air intake of the housing.

7. The lens device according to claim 1 , wherein the intake path is a path through which air flows from one diagonal position of the cover member to the other.

8. The lens device according to claim 1 , further comprising a heating device for heating the lens or the cover member.

9. 2. The lens device according to claim 1, wherein an intake hole is formed on the upstream side of the pump in the extrusion direction of the piston.

10. 2. The lens device according to claim 1, wherein an intake hole is formed downstream in the extrusion direction of the piston of the pump.

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