Sensor cover structure

Abstract

To provide a sensor cover structure that does not impose design constraints on the equipment side and allows for easy assurance of airtightness. [Solution] A sensor cover structure is provided in which a transparent cover member 10 is attached to an opening 31 of the main body of the device 30 and a sensor is provided inside. The transparent cover member 10 consists of a dome portion 11 formed with a convex curved surface and a flange portion 12 formed integrally with the dome portion on a flat surface, and a spacer member 20 interposed between the mounting surface 32 of the main body of the device 30 and the flange portion 12 to surround the opening 31. The spacer member 20 consists of an annular outer ring portion 22 fixed to the mounting surface, an inner ring portion 23 positioned at a distance from the inner circumference of the outer ring portion, and an O-ring 21 fitted into the distance between the outer ring portion and the inner ring portion. The O-ring 21 contacts the outer ring portion 22, the flange portion 12, and the mounting surface 32, respectively, thereby sealing the transparent cover member 10 and the main body of the device 30.

Description

Technical Field

[0006]

[0001] The present invention relates to a sensor cover structure that covers various sensors such as image sensors and infrared sensors, and particularly relates to its sealing structure.

Background Art

[0002] In devices such as digital cameras, surveillance cameras, and infrared sensors that cover the entire circumference, a structure in which the internal lens and sensor are covered with a cover such as a dome type is well known. The dome-shaped cover is formed of glass, resin, or the like, and an O-ring is often sandwiched between it and the device body to seal it.

[0003] Conventionally, to provide this O-ring, it is common to provide a groove on the device side and insert the O-ring into it, and then cover the dome-shaped cover from above to maintain the confidentiality between the device and the dome-shaped cover. For example, in Patent Document 1, the opening periphery of the housing recess of the metal housing is a circular opening end face, and a dome block is fixed to the opening end face. The dome block has a glass dome cover and is fixed to the metal housing. At this time, a plurality of dome block fixing female screws for screwing the dome block are drilled in the opening end face, and an O-ring accommodation groove for accommodating the O-ring is formed concentrically with the opening end face on the opening end face.

[0004] Also, in Patent Document 2, in a configuration where a camera unit, a support portion, and a base portion are arranged in a case, it is described that a dome-shaped cover is attached to the case via an O-ring that is a sealing member.

[0005] In Patent Document 3, a sensor cover structure for covering a sensor is disclosed, in which the dome-shaped cover includes a dome portion formed in a convex curved surface, a flange portion integrally formed in a plane with the dome portion, and an annular spacer member corresponding to the shape of the flange portion.

[0006] Furthermore, in a configuration in which a dome-shaped cover is attached by bringing a spacer member into contact with the mounting surface of the device body on which the sensor is installed, it is proposed that a ring groove be provided on the surface of the spacer member facing the mounting surface, and an O-ring be fitted into the ring groove to seal the spacer member and the flat portion of the device body. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2018-13531 [Patent Document 2] Japanese Patent Publication No. 2019-123160 [Patent Document 3] Japanese Patent Publication No. 2024-75515 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] Conventional devices using sensor covers ensured airtightness by either forming a groove for an O-ring in the device itself, or simply inserting an elastic component such as an O-ring, without requiring any special processing on the sensor cover. In the former case, a groove had to be formed in the device, requiring the sensor cover and the device to be designed specifically for each, leading to increased complexity and cost in the device's design. In the latter case, it was difficult to ensure sufficient airtightness, and the thickness of the cover had to be increased. Furthermore, there was a problem with difficulty in attaching it to thin, flat cases and similar structures.

[0009] Patent Document 3 describes a structure that solves these problems, but the shape of the spacer member is somewhat complex, which presented further challenges in maintaining accuracy and reducing costs.

[0010] The present invention aims to solve the problems of the above-mentioned prior art and to provide a sensor cover structure that does not impose constraints on the design of the equipment and can easily ensure airtightness. [Means for solving the problem]

[0011] To solve the above problems, the present invention provides the following sensor cover structure. According to a first embodiment of the present invention, a sensor cover structure is provided in which a transparent cover member is attached to an opening in the main body of a device, and a sensor is provided inside, comprising a transparent cover member consisting of a transparent window portion and a flange portion integrally formed with the window portion in a planar shape, and a spacer member interposed between the mounting surface of the main body of the device and the flange portion to surround the opening. The spacer member consists of an annular outer ring portion fixed to the mounting surface, an inner ring portion positioned at a distance from the inner circumference of the outer ring portion, and an O-ring fitted into the distance between the outer ring portion and the inner ring portion, and the O-ring contacts the outer ring portion, the flange portion and the mounting surface, respectively, thereby sealing the transparent cover member and the main body of the device.

[0012] According to a second embodiment of the present invention, the flange portion and the outer ring portion may be configured to have a plurality of screw holes for screw fastening to the main body of the device.

[0013] According to a third embodiment of the present invention, the inner ring portion may have a contact surface that abuts against the mounting surface and an engaging portion that bends from the contact surface and engages with the inner circumferential surface of the opening.

[0014] According to a fourth embodiment of the present invention, the transparent cover member may be configured to consist of a dome portion formed with a transparent convex curved surface and a flange portion formed integrally with the dome portion on a flat surface.

[0015] According to a fifth embodiment of the present invention, the transparent cover member may be configured to consist of a transparent window portion and a flange portion that is integrally formed with the window portion in a planar manner.

[0016] According to a sixth embodiment of the present invention, it may be provided as a spacer member in the sensor cover structure described above. [Effects of the Invention]

[0017] This invention enables airtight sealing between the transparent cover member and the device body with a simple component configuration, contributing to cost reduction.

Brief Description of the Drawings

[0018] [Figure 1] It is a perspective explanatory view of a cover structure for a sensor according to the present invention. [Figure 2] It is an exploded cross-sectional view of a dome-shaped cover according to the present invention. [Figure 3] It is a cross-sectional view of a dome-shaped cover according to the present invention. [Figure 4] It is a perspective explanatory view showing another embodiment of a transparent cover member according to the present invention.

Modes for Carrying Out the Invention

[0019] Hereinafter, embodiments of the present invention will be described based on the examples shown in the drawings. Note that the embodiments are not limited to the following. FIG. 1 is a perspective explanatory view of a cover structure for a sensor according to the present invention. It is composed of a device main body (30), a transparent cover member (10), and a spacer member (20). Although the device main body (30) is shown in a case shape in this embodiment, the shape of the device main body (30) is not limited. Further, for example, it may be a flat plate such as a wall surface.

[0020] The device main body (30) has an opening (31) and includes a sensor (not shown) inside. The sensor is configured to detect or photograph the outside from the opening (31). An example of the device according to the present invention is an imaging device. The imaging device houses a substrate or the like having an image sensor inside and images the surroundings through a transparent transparent cover member (10).

[0021] Examples of devices to which the present invention can be applied include general digital cameras having an image sensor, digital cameras equipped with an ultra-wide-angle lens capable of photographing the entire surroundings, sensor devices having various optical sensors such as an infrared sensor inside, and various devices equipped with any sensor.

[0022] In such sensor cover structures, airtightness and waterproofness between the transparent cover member (10) and the device body (30) are important to prevent the intrusion of rainwater and other elements. Conventionally, O-rings have been used for sealing, but the present invention provides a technique for better O-ring placement.

[0023] As shown in the figure, the transparent cover member (10) is a typical acrylic dome consisting of a dome portion (11) formed with a convex curved surface and a flange portion (12) formed integrally with the dome portion (11) with a flat surface. The flange (12) is shown as a hexagon, but any shape such as a circle or square can be used.

[0024] The present invention comprises a transparent cover member (10) and a spacer member (20) interposed between the mounting surface (32) and the flange portion (12) of the device body (30) to surround the opening (31). The spacer member (20) consists of three elements: an O-ring (21), an annular outer ring portion (22) that is fixed to the mounting surface (32), and an inner ring portion (23) that is positioned at a distance from the inner circumference of the outer ring portion (22).

[0025] Figure 2 is an exploded cross-sectional view of the dome-shaped cover according to the present invention, and Figure 3 is a cross-sectional view of the same. The outer ring portion (22) has a hexagonal shape on its outer surface that corresponds to the shape of the flange portion (12) of the transparent cover member (10), and a circular ring shape on its inner surface that corresponds to the base of the dome portion (11). The material is molded from a resin such as acrylic. Other materials such as polycarbonate, ABS, and PETG may also be used. It may also be molded from a metal such as aluminum.

[0026] In this embodiment, the thickness of the outer ring is 1.8 mm, and the diameter of the inner circular part is 70 mm. The thickness is preferably in the range of 0.7 mm to 3 mm, and specifically, a thickness of about half the thickness of the O-ring used is preferable.

[0027] The inner ring portion (23) is an annular shape with an outer diameter smaller than the inner circumference of the outer ring portion (22). In this embodiment, it is made of aluminum. The outer diameter is 61.8 mm, meaning there is a distance of 4.1 mm between the inner circumference of the outer ring portion (22) and the outer circumference of the inner ring portion (23). In this invention, the O-ring has a diameter of 3.1 mm, and since the O-ring is compressed and deformed when sealed, it is preferable to have a distance that is approximately 20 to 40% larger than the diameter of the O-ring. The dimensions shown above are just one example and can be freely modified.

[0028] Furthermore, in the present invention, the inner ring portion (23) can have a shape that includes a contact surface (230) that abuts against the mounting surface (32) and an engaging portion (231) that bends from the contact surface (230) and engages with the inner circumferential surface (310) of the opening (31). In this embodiment, as shown in the figure, it consists of an annular plate with an L-shaped cross-section that forms a contact surface (230), and an engaging portion (231) provided vertically downward on the inside thereof in a rib-like manner.

[0029] However, since the purpose of the engaging portion (231) is to fit into the opening (31) and prevent it from shifting in the in-plane direction of the mounting surface (32), instead of providing it over the entire circumference as in the embodiment, it may be provided with protrusions at two or more points on the circumference to engage with it. Furthermore, instead of the engaging portion (231), the contact surface (230) and the mounting surface (320) may be bonded together or an anti-slip treatment applied.

[0030] By making it difficult for the inner ring portion (23) and the mounting surface (320) to shift in this way, the problem of the inner ring portion (23) moving when fixing the transparent cover member (10) and making it difficult to install the O-ring is resolved, improving ease of assembly and ensuring airtightness.

[0031] In this embodiment, the inner ring portion (23) is made of aluminum. It can also be made of resin, similar to the outer ring portion (22). When made of a metal such as aluminum, the opening (31) can be reinforced, and the decorative aspect can be enhanced by the addition of a border.

[0032] A gap of 0.3 mm is provided between the outer circumferential surface of the engaging portion (231) and the inner circumferential surface (310) of the opening (31). This gap not only provides clearance to improve the installation of the inner ring portion (23), but is also necessary for slight movement to prevent the adjacent O-ring (21) from being distorted or pinched when it deforms. Therefore, the gap between the outer circumferential surface of the engaging portion (231) and the inner circumferential surface (310) of the opening (31) is important in the present invention, and it is preferable to provide a width of 0.2 mm to 0.5 mm.

[0033] The outer ring portion (22) is provided with a screw hole (220) that coincides with the screw hole (33) provided on the mounting surface (32), and together with the screw hole (120) of the transparent cover member (10), it can be fixed to the mounting surface (32) with bolts or screws (not shown). By using bolts, screws, and washers that have a sealing function, it is possible to prevent water from entering through the screw hole (220). For example, sealing washers and sealing cap bolts manufactured by Daimaru Byora Seisakusho can be used. By tightening with bolts, the transparent cover member (10) is pressed against the spacer member (20) and the main body of the equipment (30), and the O-ring (21) also deforms, ensuring a tight seal.

[0034] As described above, according to the present invention, even if off-the-shelf products are used as the device body (30) and the transparent cover member (10), a sealed sensor cover structure can be easily provided by interposing the spacer member (20) according to the present invention. In other words, the spacer member (20) can be provided separately to match various off-the-shelf cases and acrylic domes, which also contributes to the versatility of off-the-shelf products.

[0035] Furthermore, by adjusting the inner and outer diameters of the inner ring portion (23) and the outer ring portion (22), an optimal O-ring can be fitted and secured even if the diameter of the opening (31) does not match the diameter of the sphere of the transparent cover member (10), or the size of the flange portion (12) of the transparent cover member (10).

[0036] As shown in Figure 4, the transparent cover member (40) in the present invention is not necessarily limited to a dome shape, but may be flat. That is, the dome portion (11) may be made flat, and it may be made of a single acrylic plate with a transparent window portion (41) and a flange portion (41) around it, and it may be configured to cover the sensor housed inside the device body (44) through the window portion (41).

[0037] In this embodiment as well, a spacer member (43) is placed between the mounting surface (45) and the transparent cover member (40). The spacer member (43) is equipped with an O-ring, an outer ring portion, and an inner ring portion, similar to the embodiment described above. [Explanation of Symbols]

[0038] 10 Transparent cover component 11 Dome section 12 Guard section 20 Spacer member 21 O-rings 22 Outer ring 23 Inner ring section 30 Main unit of the device 31 Opening 32 Mounting surface 33 screw holes 120 screw holes 220 screw holes 230 Contact surface 231 Engagement part 310 Inner surface 320 mounting surface 40 Transparent cover component 41 Window section 42 Guard section 43 Spacer member 44 Main unit of the device 45 Mounting surface

Claims

1. A sensor cover structure is provided, which has a transparent cover member attached to the opening of the main body of the device and a sensor inside, The transparent cover member consists of a transparent window portion and a flange portion that is integrally molded with the window portion in a planar manner, The device body includes a mounting surface and a flange portion, and a spacer member interposed between them to surround the opening. The spacer member consists of an annular outer ring portion that is fixed to the mounting surface, an inner ring portion that is spaced apart from the inner circumference of the outer ring portion, and an O-ring that fits into the spaced-apart portion of the outer ring portion and the inner ring portion. The O-ring seals the transparent cover member and the device body by contacting the outer ring portion, the flange portion, and the mounting surface, respectively. A sensor cover structure characterized by the following features.

2. Multiple screw holes are provided in the flange portion and the outer ring portion for screw fastening to the main body of the device. The sensor cover structure according to claim 1.

3. The inner ring portion has a contact surface that abuts against the mounting surface and an engaging portion that bends from the contact surface and engages with the inner circumferential surface of the opening. The sensor cover structure according to claim 1.

4. The transparent cover member consists of a dome portion formed with a transparent convex curved surface and a flange portion formed integrally with the dome portion on a flat surface. A sensor cover structure according to any one of claims 1 to 3.

5. The transparent cover member consists of a transparent window portion and a flange portion that is integrally molded with the window portion in a flat surface. A sensor cover structure according to any one of claims 1 to 3.

6. A spacer member in a sensor cover structure according to any one of claims 1 to 3.

Images