JP2022191884A - Waterproof device - Google Patents

Abstract

To provide a waterproof device that electrically protects an electrical element mounted on a substrate in the device, establishes waterproof performance while efficiently radiating heat from the electrical element, and can achieve both a reduction in size and satisfactory assemblability of the device.SOLUTION: A waterproof device has a housing 7 that is composed of a front cover 3 and a rear cover 4 and accommodates therein a substrate having an electrical element mounted thereon, and a sealing member 5 that is arranged between the front cover and the rear cover. The sealing member comprises a sealing part 51 that is pressed by the front cover and the rear cover to seal the housing, a heat radiation part 52 that transfers heat generated from the electrical element to the housing to radiate the heat, and a discharge protection part 53 that protects the electrical element from discharge from the outside.SELECTED DRAWING: Figure 1

Description

The present invention relates to a waterproof device.

Conventionally, a small waterproof camera protects the sensor board on which the image sensor is mounted with a metal exterior or metal parts such as sheet metal to protect it electrically, and at the same time, allows the heat generated by the sensor board to escape to the metal parts. is generally sealed with a sealing member to achieve a waterproof specification.

For example, Patent Document 1 discloses a structure that electrically protects a substrate inside a housing while sealing the housing by caulking two metal exterior parts with a sealing member sandwiched between them. disclosed.

Further, Japanese Patent Laid-Open No. 2002-200000 discloses a structure in which an adjustment member for adjusting the position of a sensor substrate in a camera protects the substrate electrically and radiates heat from an electric element mounted on the substrate.

JP 2019-046963 A JP 2010-278768 A

However, in the structure of Patent Literature 1, the exterior parts are all made of metal, resulting in a high cost. In addition, the space for arranging members for dissipating the heat generated by the sensor substrate is limited, and it is difficult to achieve both miniaturization of the device and ease of assembly.

In the structure of Patent Document 2, the heat dissipation path of the sensor substrate is limited and it is difficult to dissipate heat efficiently. Moreover, in order to make the camera waterproof, it is necessary to dispose a sealing member in addition to the sensor substrate and the adjustment member inside the camera.

Therefore, the present invention electrically protects the electric elements mounted on the board in the device, efficiently dissipates heat from the electric elements, establishes waterproof performance, and further reduces the size of the device and improves the ease of assembly. An object of the present invention is to provide a waterproof device capable of satisfying both

A waterproof device according to one aspect of the present invention includes a housing that is composed of a front cover and a rear cover and that accommodates a board on which an electric element is mounted, and a seal that is arranged between the front cover and the rear cover. a stopping member, wherein the sealing member is pressed by the front cover and the rear cover to seal the housing, and transmits heat generated by the electric element to the housing. and a discharge protection part for protecting the electrical element from external discharge.

Other objects and features of the invention are described in the following embodiments.

According to the present invention, the electrical elements mounted on the board in the device are electrically protected, the electrical elements are efficiently dissipated, and the waterproof performance is established. can be provided.

It is a cross-sectional view of the waterproof device according to the present embodiment. 1 is an exploded perspective view of a waterproof device according to this embodiment; FIG. 4 is a detailed view of the substrate according to the embodiment; FIG. FIG. 4 is a detailed view of the sealing member according to the present embodiment; FIG. 4 is a detailed view of the sealing member according to the present embodiment;

Preferred embodiments of the present invention are explained in detail below using examples based on the accompanying drawings.

Hereinafter, a waterproof device according to this embodiment will be described with reference to FIGS. 1 to 5. FIG. The prevention device according to the present embodiment relates to a waterproof electronic device, and more particularly to a small waterproof camera used as a surveillance camera or an in-vehicle camera.

FIG. 1 is a cross-sectional view of a waterproof device according to this embodiment. A housing 7 of the waterproof device 100 is composed of a front cover 3 and a rear cover 4 . A sealing member 5 is arranged between the front cover 3 and the rear cover 4 . The housing 7 is sealed by inserting the sealing member 5 between the front cover 3 and the rear cover 4 in a pressed state.

A board 2 on which an imaging element 21, an electric element 22, and a board-side connector 23 are mounted is fixed to the front cover 3. As shown in FIG. The substrate 2 is accommodated inside the housing 7 . Further, the lens unit 1 is held in the housing 7 by screwing the female threaded portion 3 a of the front cover 3 and the male threaded portion 1 a of the lens unit 1 .

The lens unit 1 has an optical system with an optical axis O, and light rays condensed by the lens unit 1 form an image on the imaging device 21 . This completes the shooting. The lens unit 1 has crab eyes 1b. By rotating the lens unit 1 using the crab eye 1 b , the male threaded portion 1 a and the female threaded portion 3 a provided on the front cover 3 are screwed together, and the lens unit 1 is incorporated into the front cover 3 .

The front cover 3 is provided with a spring insertion portion 3b into which the sensor spring 11 is inserted. The sensor spring 11 urges the front cover 3 and the lens unit 1 to eliminate looseness of the lens unit 1 with respect to the front cover 3. - 特許庁The front cover 3 is provided with a sensor rubber insertion portion 3c, in which the sensor rubber 13 is provided. The sensor rubber 13 seals the imaging element 21 between the front cover 3 and the imaging element 21 to prevent dust and the like from adhering to the imaging element 21 .

The lens unit 1 is provided with an O-ring incorporating portion 1c, in which an O-ring 12 is incorporated. The O-ring 12 is pressed between the O-ring fitting portion 3f provided on the front cover 3 and the O-ring incorporating portion 1c to seal the gap between the front cover 3 and the lens unit 1. As shown in FIG.

A vent hole 4 a is provided in the rear cover 4 , and a waterproof sheet 41 is attached to the entrance of the vent hole 4 a on the inner side of the housing 7 . With this configuration, the waterproof device 100 has a waterproof structure but a non-sealed structure, so that problems such as condensation inside the housing 7 due to atmospheric pressure changes can be avoided.

In the present embodiment, an example in which the ventilation holes 4a are provided in the rear cover 4 is described, but the ventilation holes 4a may be provided in the front cover 3 as well. Alternatively, the ventilation holes 4 a may be provided in the front cover 3 and the rear cover 4 .

The waterproof device 100 is connected to a main body unit (not shown) via the cable unit 6 . The front cover 3 is provided with a cable insertion portion 3g, and the cable unit 6 is inserted into the front cover 3 from there. A clamp 31 is crimped to the cable unit 6, and the locking portion 31a of the clamp 31 is engaged with the clamp engaging portion 3e of the front cover 3, thereby fixing the cable unit 6 to the front cover 3. there is

FIG. 2 is an exploded perspective view of the waterproof device 100 according to this embodiment. The cable unit 6 is composed of a cable 61 , a cable-side connector 61 a , a body connection connector 61 b , a cable packing 62 , a cable sheet metal 63 and a cable sheet 64 . The cable-side connector 61 a connects to the board-side connector 23 mounted on the board 2 . The body connection connector 61b connects with a body unit (not shown). The cable packing 62 is inserted into the cable insertion portion 3 g of the front cover 3 and pressed by the cable sheet metal 63 to seal the gap between the cable unit 6 and the front cover 3 . The cable sheet metal 63 is covered with a cable sheet 64 and is invisible from the outside.

FIG. 3 is a detailed view of the substrate 2 according to this embodiment. An electric element 22 is mounted on the substrate 2 . When the waterproof device 100 is activated, the electric element 22 generates heat. The heat is transferred to the atmosphere inside the waterproof device 100 or is transferred from the substrate 2 to the front cover 3 to be radiated. However, heat dissipation through these pathways alone may not be sufficient. In particular, when the waterproof device 100 is used in a high-temperature environment, there is a concern that the guaranteed temperature of the electric element 22 may be exceeded, which may cause defects such as poor imaging and functional stoppage.

FIG. 4 is a detailed view of the sealing member 5 according to this embodiment. The sealing member 5 is composed of a sealing portion 51 , a heat radiation portion 52 , a discharge protection portion 53 and a ventilation portion 54 . These are integrally formed. That is, these are formed in the sealing member 5 which is one member. The material of the sealing member 5 is an elastic member such as silicon rubber, and is stable as a sealing member even in low-temperature and high-temperature environments. Moreover, the thermal conductivity of the material of the sealing member 5 is 1.0 W/m·K or more, and the performance as a heat dissipation member is also high. Since the material of the sealing member 5 has a volume resistivity of 1 TΩ·m or more and is a so-called insulator, it can also play a role of protecting electrical parts from discharge or the like. The sealing portion 51 seals the gap between the front cover 3 and the rear cover 4 by being pressed between the sealing portion 51 and the rear cover 4 by the packing pressing portion 3 d of the front cover 3 .

Here, the front cover 3 or the rear cover 4 is made of resin. By using resin parts, the cost of the device can be greatly reduced. In this embodiment, at least the rear cover 4 is made of resin. Therefore, there is a possibility that an electric discharge from the outside may electrically damage the substrate 2 through the vent hole 4a. If the rear cover 4 is made of metal, damage to the substrate 2 due to discharge can be prevented, but since metal parts generally cost ten times more than resin parts, the cost of the device increases significantly. . If the distance from the air hole 4a to the substrate 2 is sufficiently long, the substrate 2 will not be damaged by the discharge, but this will increase the size of the device. Therefore, in this embodiment, the discharge protection portion 53 is arranged in the sealing member 5 in the vicinity of the ventilation hole 4 a of the rear cover 4 . Specifically, the discharge protection portion 53 is arranged at a position overlapping the ventilation hole 4a of the rear cover 4 on a plane perpendicular to the optical axis O of the optical system. As a result, the creepage distance from the ventilation hole 4a to the substrate 2 is extended, so that electrical damage to the substrate 2 can be prevented. This configuration makes it possible to protect the substrate 2 from electrical damage due to discharge without increasing the size of the device or increasing the cost.

The discharge protection portion 53 is not in contact with the rear cover 4 and has a space between it and the vent hole 4a. Further, a vent portion 54 which is a hole penetrating the sealing member 5 is formed around the discharge protection portion 53 so that the sealing member 5 does not block the vent hole 4a.

The heat radiating portion 52 is in contact with the electric element 22 at the element contact portion 52a and absorbs heat. The element non-contact portion 52b is provided at a position lower than the element contact portion 52a so as not to contact the electric element 22, other elements and the substrate 2. As shown in FIG. A taper-shaped guide shape 52c is provided at the tip of the element contact portion 52a, and when the substrate 2 and the sealing member 5 are brought into contact with each other during assembly of the waterproof device 100, the element contact portion 52a is properly connected to the electric element 22. The guide shape 52c guides the electrical element 22 so that it is assembled in a contacting position.

FIG. 5 is a detailed view of the sealing member 5 according to this embodiment. The heat of the electric element 22 absorbed from the element contact portion 52a is transferred from the rear surface portion 52d of the sealing member 5 to the rear cover 4 and radiated from the rear cover 4 to the outside air.

Since the waterproof device 100 is small, workability is very poor for incorporating many parts. This is because the space for providing the positioning shape of the parts and the space for the assembly work are limited.

By using the sealing member 5 according to the present embodiment, the process of assembling the three parts of the sealing part 51, the discharge protection part 53, and the heat dissipation part 52 can be performed at once, so that the positioning shape is sufficient for one part. Since the work can be done in one step, the assembling efficiency is very high.

With the above configuration, the electrical elements mounted on the board in the device are electrically protected, heat is efficiently dissipated from the electrical elements, waterproof performance is established, and the device can be downsized and easily assembled. It makes it possible to be compatible.

Although preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications and changes are possible within the scope of the gist thereof. Moreover, the configuration is not limited as long as it is configured in consideration of the design function.

front cover 3
rear cover 4
housing 7
Sealing member 5
sealing part 51
Heat dissipation part 52
Discharge protector 53

Claims (14)

a housing that is composed of a front cover and a rear cover and that accommodates a substrate having electric elements mounted therein;
a sealing member arranged between the front cover and the rear cover;
The sealing member is
a sealing portion that seals the housing by being pressed by the front cover and the rear cover;
a heat radiating unit that radiates heat by transmitting heat generated by the electric element to the housing;
and a discharge protection unit that protects the electric element from external discharge. a ventilation hole is provided in the front cover or the rear cover,
2. The waterproof device according to claim 1, wherein the discharge protection part is arranged in the vicinity of the air hole in the sealing member. The discharge protection portion is arranged in the sealing member at a position overlapping the ventilation hole on a plane perpendicular to the optical axis of the optical system of the lens unit held in the housing. The waterproof device according to claim 2. 4. The waterproof device according to claim 2, wherein the sealing member further comprises a ventilation part around the discharge protection part. 5. The waterproof device according to claim 4, wherein the ventilation part is a hole formed around the discharge protection part and passing through the sealing member. The waterproof device according to any one of claims 2 to 5, wherein there is a space between the discharge protection part and the ventilation hole. The waterproof device according to any one of claims 1 to 6, wherein the front cover or the rear cover is made of resin. The heat dissipation part includes a contact part that contacts the electric element and a non-contact part that does not contact the electric element,
The waterproof device according to any one of claims 1 to 7, wherein a tip of the contact portion is provided with a tapered guide shape. The waterproof device according to any one of claims 1 to 8, wherein the waterproof device is a camera in which a lens unit is incorporated in the front cover. The waterproof device according to any one of claims 1 to 9, wherein the material of the sealing member has a thermal conductivity of 1.0 W/m·K or more. The waterproof device according to any one of claims 1 to 10, wherein the material of the sealing member has a volume resistivity of 1 TΩ·m or more. The waterproof device according to any one of claims 1 to 11, wherein the material of the sealing member is an elastic member. 13. The waterproof device according to claim 12, wherein the elastic member is silicone rubber. The waterproof device according to any one of claims 1 to 13, wherein the sealing portion, the heat radiation portion, and the discharge protection portion are integrally formed.

Images