Imaging apparatus

An imaging apparatus includes: a lens attachment portion to which a lens is attached; an image sensor on which light transmitted through a lens attached to the lens attachment portion is incident; a heat transfer members configured to support the image sensor and to absorb heat of the image sensor; a main frame including a duct in which outside air flows and provided with a through hole through which a part of the heat transfer member passes; a fan arranged in the duct; a front frames configured to support the lens attachment portion and the heat transfer members and to be attached to the main frame; and a seal member configured to block a flow of outside air from inside the duct toward the image sensor through the through hole.

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure relates to an imaging apparatus.

Description of the Related Art

For example, JA 2010-213000 A discloses an imaging apparatus that cools an image sensor using outside air. Specifically, the image sensor is cooled by a Peltier element (thermoelectric element). The heat absorbed by the Peltier element from the image sensor is transmitted to the heat sink including a plurality of fins. The plurality of fins of the heat sink are cooled by the outside air blown by the cooling fan.

SUMMARY OF THE INVENTION

Technical Problem

By the way, in a case where the image sensor is cooled using the outside air, it is necessary to take measures so that foreign matter such as dust included in the outside air does not reach the image sensor, particularly does not adhere to the light receiving surface of the image sensor. Adhesion of foreign matter such as dust to the light receiving surface may deteriorate the image quality of the captured image.

Thus, the present disclosure has an object to prevent foreign matter such as dust included in outside air from reaching an image sensor in an imaging apparatus that cools the image sensor using the outside air.

Means for Solving the Problems

In order to solve the above problem, according to one aspect of the present disclosure, provided is an imaging apparatus including: a lens attachment portion to which a lens is attached; an image sensor on which light transmitted through a lens attached to the lens attachment portion is incident; a heat transfer member configured to support the image sensor and to absorb heat of the image sensor; a main frame including a duct in which outside air flows and provided with a through hole through which a part of the heat transfer member passes; a fan arranged in the duct; a front frame configured to support the lens attachment portion and the heat transfer member and to be attached to the main frame; and a seal member configured to block a flow of outside air from inside the duct toward the image sensor through the through hole.

Effect of the Invention

According to the present disclosure, in the imaging apparatus that cools the image sensor using the outside air, it is possible to prevent the foreign matter such as dust included in the outside air from reaching the image sensor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate. However, a detailed description more than necessary may be omitted. For example, a detailed description of already well-known matters and an overlapping description for substantially the same configuration may be omitted. This is to avoid the unnecessary redundancy of the following description and to facilitate understanding by those skilled in the art.

It should be noted that the inventor(s) provides (provide) the accompanying drawings and the following description for a person skilled in the art to fully understand the present disclosure. Thus, the drawings and the description are not intended to limit the subject matter defined in the claims. Hereinafter, an imaging apparatus according to an embodiment of the present disclosure will be described with reference to the drawings.

FIG. 1is a perspective view of an imaging apparatus according to an embodiment of the present disclosure. In addition,FIG. 2is a perspective view of a subassembly of an imaging apparatus including components related to cooling of an image sensor. Furthermore,FIGS. 3A and 3Bare exploded perspective views of the subassembly shown inFIG. 2as viewed from different directions.

It should be noted that the X-Y-Z orthogonal coordinate system shown in the drawings is for facilitating understanding of the present disclosure, and does not limit the present disclosure. The X-axis direction indicates the front-rear direction of the imaging apparatus, the Y-axis direction indicates the left-right direction of the imaging apparatus, and the Z-axis direction indicates the height direction. In addition, in the present specification, a side on which the subject is present with respect to the imaging apparatus is referred to as a “front side”, and a side on which the imaging apparatus is present with respect to the subject is referred to as a “rear side”.

As shown inFIG. 1, in the case of the present embodiment, the imaging apparatus10includes a casing12having a substantially cubic shape and an image sensor14arranged inside the casing12. The image sensor14is, for example, a CCD image sensor, a CMOS image sensor, or the like. Light (image of subject) transmitted through a lens (not shown) attached to the lens attachment portion16is incident on the light receiving surface14aof the image sensor14. The image sensor14outputs an electric signal corresponding to the incident image, that is, takes an image (take shoots a still image or a moving image).

As shown inFIG. 2, the imaging apparatus10also includes a main frame18arranged in the casing12and supporting the image sensor14and the lens attachment portion16.

FIG. 4is a cross-sectional view of the imaging apparatus showing a duct.

As shown inFIG. 4, the main frame18is arranged in the casing12and includes a duct18athrough which outside air (broken line arrow) flows. As shown inFIG. 1, the outside air flows into the duct18athrough the intake port12bformed on the right side surface12aof the casing12. The outside air flowing into the duct18aflows out to the outside of the casing12through the exhaust port12c.

As shown inFIG. 4, a fan20is arranged in the duct18aof the main frame18. Rotation of the fan20causes the outside air to flow into the duct18athrough the intake port12b, and the outside air in the duct18ato flow out to the outside of the casing12through the exhaust port12c.

As shown inFIGS. 3A and 3B, the main frame18supports the imaging unit22including the image sensor14and the lens attachment portion16. Specifically, in the case of the present embodiment, the imaging apparatus10includes a front frame24that supports the imaging unit22and the lens attachment portion16. Attachment of the front frame24to the main frame18causes the main frame18to support the image sensor14and the lens attachment portion16.

In the case of the present embodiment, the front frame24includes a first subframe26and a second subframe28attached to each other.

The first subframe26is positioned in front of the second subframe28. In addition, the first subframe26supports the lens attachment portion16, and includes a through hole26athrough which light having transmitted through a lens (not shown) supported by the lens attachment portion16passes. The first subframe26is attached to the main frame18. The second subframe28is positioned behind the first subframe26. In addition, the second subframe28supports the imaging unit22, and includes a through hole28athrough which light having passed through the through hole26aof the first subframe26passes. The second subframe28is fixed to the first subframe26.

FIG. 5is an exploded perspective view of the imaging unit.

As shown inFIG. 5, the imaging unit22includes an image sensor14and a heat transfer member30that supports the image sensor14and absorbs heat. In the case of the present embodiment, the imaging unit22includes a board32on which the image sensor14is mounted. In addition, in the case of the present embodiment, the heat transfer member30includes a radiator plate34and a heat sink36attached to the radiator plate34.

The board32is provided with a processing circuit and the like for processing a signal from the image sensor14. The image sensor14is supported by the heat transfer member30by fixing the board32to the radiator plate34of the heat transfer member30. In addition, the board32is formed with a through hole32a. The through hole32aallows a protruding portion34aprovided on the radiator plate34of the heat transfer member30to directly contact the image sensor14. As a result, the radiator plate34can efficiently absorb heat of the image sensor14to cool the image sensor14.

The heat sink36to be attached to the radiator plate34includes a base portion36ato be attached to the radiator plate34and a plurality of fins36bprotruding in parallel with each other from the base portion36a.

The heat sink36cools the radiator plate34that has absorbed heat from the image sensor14. Specifically, although details will be described below, the plurality of fins36bof the heat sink36are cooled by outside air flowing in the duct18aof the main frame18.

It should be noted that in the case of the present embodiment, the imaging unit22is supported by the front frame24(second subframe28) via an adjustment mechanism that adjusts the inclination of the image sensor14with respect to the lens attachment portion16.

FIG. 6is a schematic diagram of the subassembly shown inFIG. 2.

As shown inFIG. 6, the radiator plate34of the imaging unit22is supported by the second subframe28of the front frame24via a plurality of adjustment mechanisms including an adjustment spring38and an adjustment screw40. In the case of the present embodiment, as shown inFIGS. 3A and 3B, three adjustment mechanisms (three adjustment springs38and three adjustment screws40) are provided.

As shown inFIG. 6, the plurality of adjustment springs38are sandwiched and compressed between the second subframe28and the radiator plate34. The adjustment screw40penetrates the radiator plate34, passes through in the adjustment spring38, and is screwed to the second subframe28. Adjustment of the fastening amount of the plurality of adjustment screws40adjusts the inclination of the image sensor14supported by the radiator plate34with respect to the lens attachment portion16. That is, the inclination of the light receiving surface14aof the image sensor14with respect to the optical axis C of the lens L attached to the lens attachment portion16is adjusted. It should be noted that the radiator plate34is spaced apart from the main frame18so that the inclination of the radiator plate34(that is, the image sensor14) can be adjusted. It should be noted that a space may be secured between the radiator plate34and the main frame18so that the adjustment screw40can be accessed even when the front frame24is attached to the main frame18.

As described above, the plurality of fins36bbeing a part of the heat sink36are cooled by the outside air flowing in the duct18aof the main frame18. To that end, as shown inFIGS. 3A, 3B, 4, and 6, the main frame18includes a through hole18bthat communicates the inside with the outside of the duct18a. A part of the heat sink36passes through the through hole18b, whereby the plurality of fins36bare arranged in the duct18a. In the case of the present embodiment, the plurality of fins36bare arranged downstream from the fan20in the flow direction of the outside air in the duct18a. Thus, the plurality of fins36bof the heat sink36are cooled by the outside air flowing in the duct18a. As a result, the image sensor14in contact with the radiator plate34to which the heat sink36is attached is cooled.

Outside air taken into the duct18afrom outside the casing12may include foreign matter such as dust. When such foreign matter such as dust adheres to the image sensor14, particularly to the light receiving surface14athereof, the image quality of the captured image of the imaging apparatus10is deteriorated.

In the case of the present embodiment, as indicated by a thick broken line arrow inFIG. 6, a part of the outside air flowing through the duct18amay pass through the gap between the heat sink36passing through the through hole18band the inner peripheral surface of the through hole18b, pass between the radiator plate34and the main frame18, pass between the radiator plate34and the second subframe28, and reach the image sensor14. When foreign matter such as dust is included in the flow FP from the duct18atoward the image sensor14, the foreign matter may adhere to the light receiving surface14aof the image sensor14.

On a flow path on which a flow FP of outside air from inside the duct18atoward the image sensor14through the through hole18bis generated, a seal member42that blocks the flow FP of outside air is provided.

FIG. 7is a cross-sectional view of a portion of the subassembly showing a seal member.

In the case of the present embodiment, the seal member42is made of an elastic material such as silicone rubber. In addition, as shown inFIGS. 3A, 3B, and 7, the seal member42includes an annular base portion42afixed to the opening edge portion of the through hole18boutside the duct18a, and a funnel-shaped seal portion42bextending from the base portion42aand entering the through hole18b. The base portion42aof the seal member42comes into contact with the opening edge portion of the through hole18bto perform sealing, and the seal portion42bof the seal member42comes into contact with the base portion36aof the heat sink36over the entire peripheral direction to perform sealing.

It should be noted that as shown inFIG. 7, since the seal portion42bof the seal member42extends from the base portion42apositioned outside the duct18atoward the inside of the through hole18b, the heat sink36can easily pass from the outside to the inside of the duct18a(unlike this, as compared with the case where the base portion42ais in the duct18aand the seal portion42bextends from the inside to the outside of the duct18a). As a result, the assembling performance of the imaging unit22to the main frame18is improved while obtaining the effect of shielding mixing of foreign matter.

According to this seal member42, as shown inFIGS. 6 and 7, a gap between the heat sink36of the heat transfer member30passing through the through hole18bof the main frame18and the inner peripheral surface of the through hole18bis sealed. Thus, the flow FP of outside air from inside the duct18ashown inFIG. 6toward the image sensor14through the through hole18bis blocked. As a result, adhesion of foreign matter such as dust to the image sensor14is suppressed.

It should be noted that in the case of the present embodiment, as shown inFIG. 7, the seal member42(the base portion42athereof) is fixed to the main frame18by being sandwiched between the annular seal presser plate44fixed to the main frame18and the main frame18.

As described above, according to the present embodiment, in the imaging apparatus10that cools the image sensor14using the outside air, it is possible to prevent the foreign matter such as dust included in the outside air from reaching the image sensor14.

Specifically, in the imaging apparatus10according to the present embodiment, the image sensor14and the heat transfer member30are not in direct contact with the main frame18including the duct18a. Thus, no force is applied from the main frame18to the heat transfer member30, and the positional relationship between the image sensor14supported by the heat transfer member30and the lens attachment portion16is appropriately maintained.

However, for this purpose, a part of the heat transfer member30(heat sink36) needs to pass through the through hole18bformed in the duct18a. As a result, a gap is generated between the inner peripheral surface of the through hole18band the heat transfer member30. Sealing this gap with the seal member42blocks the passage of foreign matter such as dust included in the outside air through the gap, and prevents the foreign matter from reaching the image sensor14.

Although the embodiment of the present disclosure has been described above with reference to the above-described embodiment, the embodiment of the present disclosure is not limited to the above-described embodiment.

For example, in the case of the above-described embodiment, as shown inFIG. 5, the heat transfer member30that absorbs heat from the image sensor14includes the radiator plate34and the heat sink36. However, the embodiment of the present disclosure is not limited thereto. The heat transfer member30may be configured by integrating the radiator plate34and the heat sink36as one component.

In addition, in the case of the above-described embodiment, as shown inFIGS. 3A and 3B, the seal member42is an annular elastic member.

However, the embodiment of the present invention is not limited thereto. As shown inFIGS. 6 and 7, the material and shape of the seal member are not limited as long as the gap between the heat sink36of the heat transfer member30and the inner peripheral surface of the through hole18bcan be closed. Furthermore, in the case of the above-described embodiment, as shown inFIG. 6, in order to block the flow FP of outside air from inside the duct18atoward the image sensor14through the through hole18b, the seal member42closes the gap between the heat sink36of the heat transfer member30and the inner peripheral surface of the through hole18b. However, in the embodiment of the present disclosure, the arrangement position of the seal member is not limited thereto.

FIG. 8is a schematic diagram of a subassembly in an imaging apparatus according to another embodiment. In addition,FIG. 9is a schematic diagram of a subassembly in an imaging apparatus according to a different embodiment.

In an imaging apparatus110according to the other embodiment shown inFIG. 8, a seal member142that blocks a flow FP of outside air from inside a duct18atoward an image sensor14through a through hole18bis an annular elastic member sandwiched between a radiator plate34and a front frame24(second subframe28) to be compressed and deformed and surrounding the image sensor14.

In an imaging apparatus210according to the different embodiment shown inFIG. 9, a seal member242that blocks a flow FP of outside air from inside a duct18atoward an image sensor14through a through hole18bis an annular elastic member sandwiched between a radiator plate34and a main frame18to be compressed and deformed and surrounding the through hole18b.

That is, in a broad sense, an imaging apparatus according to an embodiment of the present disclosure includes: a lens attachment portion to which a lens is attached; an image sensor on which light transmitted through a lens attached to the lens attachment portion is incident; a heat transfer member configured to support the image sensor and to absorb heat of the image sensor; a main frame including a duct in which outside air flows and provided with a through hole through which a part of the heat transfer member passes; a fan arranged in the duct; a front frame configured to support the lens attachment portion and the heat transfer member and to be attached to the main frame; and a seal member configured to block a flow of outside air from inside the duct toward the image sensor through the through hole.

As described above, the above-described embodiment has been described as the exemplification of the technique in the present disclosure. To that end, drawings and a detailed description are provided. Therefore, among the components described in the drawings and the detailed description, not only the components essential for solving the problem, but also the components not essential for solving the problem may be included in order to exemplify the above technique. Therefore, it should not be recognized that these non-essential components are essential immediately because these non-essential components are described in the drawings and the detailed description.

In addition, since the above embodiment is for exemplifying the technique in the present disclosure, various changes, substitutions, additions, omissions, and the like can be made within the scope of the claims or the equivalent thereof.

The present disclosure is applicable to an imaging apparatus that cools an image sensor using outside air.