JP2013117610A - Camera device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a camera device preventing condensation on a front glass and entry of dust and foreign matter from outside.SOLUTION: The camera device uses a housing body 1 including flanges 3 and 4 for panel attachment respectively on one and the other end surfaces of a cylindrical metal case with a square cross section, seals by flange attachment of a front panel 6 provided with a front glass 7 on the one end surface, has flange attachment of a rear panel 14 provided with a connector plug 17 for camera cable connection on the other end surface and uses by sealing in nitrogen in a state of having a camera lens unit 2 stored. In this case, when the nitrogen is encapsulated into the housing body 1, a vent 13 and a sealing valve 18 are respectively provided on a bottom end section of the front panel 6 and a top end section of the rear panel 14 so that replacement of ejected air by injected nitrogen is smoothly carried out and a relief valve 19 is provided so that pressure of the sealed nitrogen can be discriminated by operation sound.

Description

  The present invention relates to a camera device for a relatively small television camera, and more particularly to a camera device suitable for installation outdoors.

In recent years, the application of surveillance systems using television devices has been remarkable. Especially, recently, it has been highly evaluated as a system that greatly helps crime prevention. Therefore, there are a wide variety of places where cameras for surveillance systems are installed. There is a demand for a camera (a television camera) that functions reliably even in a poor environment.
One of the characteristics required at this time is performance that can sufficiently withstand direct sunlight and wind and rain, that is, weather resistance.

For this reason, there has conventionally been proposed a camera device that uses a sealed camera housing, houses the camera body in the housing, and uses the sealed camera housing (see, for example, Patent Document 1).
In this case, the condensation of the windshield becomes a problem.
When the housing is sealed, if moisture (moisture) is contained in the internal atmosphere, moisture in the atmosphere condenses at the dew point temperature or lower, and as a result, when the temperature drops, for example, windshield For example, dew condensation occurs in parts that are directly exposed to the outside air.

  So, for example, windshields, such as windshields, have been conventionally used to prevent condensation by heating with a heater, etc. At this time, a method of replacing the atmosphere in the camera housing with dry air or inert gas (for example, nitrogen) after the camera housing is hermetically sealed is also proposed as a conventional technique (for example, Patent Documents). (See 1, 2, 3, 4, etc.)

JP 2003-255456 A JP 2002-221748 A JP 2009-223130 A Special table 2008-521262 gazette

The above prior art is effective for preventing condensation on the windshield, but the atmospheric pressure in the camera housing is not particularly taken into consideration and is maintained at substantially atmospheric pressure.
An object of the present invention is to provide a camera device that prevents condensation on a windshield and reliably prevents dust and foreign matter from entering from the outside.

  The object is to use a housing body provided with flanges for mounting panels on one and other end faces of a cylindrical metal case having a substantially square cross section, and one end face of the housing body is provided with a windshield. Sealed by flange mounting through O-ring on the front panel, and the other end surface is sealed by flange mounting through O-ring on the rear panel equipped with a camera cable connector plug, and the camera / lens unit is housed inside In the camera device of the system that is used with nitrogen sealed in a wet state, it has a freely openable / closable vent hole, a sealed valve made up of a check valve, and a relief valve that operates at a preset desired relief pressure, The vent hole is provided at a lower end portion of the front panel, and the sealing valve is provided at an upper end portion of the rear panel. Valve is accomplished as provided in the lower portion of the rear panel.

In the present invention, since the positional relationship between the sealing valve and the discharge hole is rationalized, when nitrogen is sealed in the housing, the nitrogen to be injected and the air to be discharged are smoothly replaced and sealed. Since the nitrogen pressure can be recognized by the operation sound of the relief valve, the nitrogen pressure in the housing can be easily managed.
Therefore, according to the present invention, the pressure of the enclosed nitrogen can be maintained at a desired pressure higher than the atmospheric pressure, and as a result, without being accompanied by deformation of the housing, it is reliably prepared for intrusion of dust and foreign matter. be able to.

It is a perspective view of the housing in one Embodiment of the camera apparatus by this invention. It is sectional drawing which shows the windshield part of the housing in one Embodiment of the camera apparatus by this invention. It is explanatory drawing of the housing and camera lens unit in one Embodiment of the camera apparatus by this invention. It is explanatory drawing of the rear panel in one Embodiment of the camera apparatus by this invention.

Hereinafter, a camera device according to the present invention will be described in detail with reference to embodiments shown in the drawings.
1 to 4 all show an embodiment of a camera apparatus according to the present invention. In these drawings, first, the housing body 1 has a substantially square cross section as shown in FIG. A cylindrical metal case made of a plate material with a desired strength, such as aluminum alloy, so that the camera / lens unit 2 (FIG. 3) can be housed inside, and has one end (front end). Are formed as a member having a desired thickness, and a flange 4 is formed at the other end (rear end).

At this time, a cover 5 is provided on the upper portion of the housing body 1 for both protection and design, and a desired cloud such as an electric pan head or a semi-fixed pan head is not shown in FIG. A pedestal for mounting the camera on the base is attached.
First, a front panel 6 is attached to the flange 3 at the front end, and a windshield 7 is attached thereto.
Therefore, first, details of attachment of the windshield 7 to the front panel 6 at this time will be described with reference to FIG.

The front panel 6 is made of a thick plate material having a desired strength. The front panel 6 is provided with a substantially rectangular opening having a size necessary for securing an imaging field of view by the camera, and the windshield 7 is fitted therein. The surface of the front panel 6 and the outer surface of the windshield 7 are mounted on the same surface.
At this time, a groove is formed around the opening from the inner surface of the front panel 6 (the surface toward the inside of the housing body 1). A stepped process is applied to the peripheral end.

Accordingly, when the windshield 7 is fitted into the opening of the front panel 6, as shown in the figure, the stepped portion of the windshield 7 is positioned at the grooved portion of the opening.
Therefore, after that, the pressing plate 8 having an opening having substantially the same shape as the opening of the front panel 6 is positioned on the inner surface of the front panel 6 and attached by a plurality of, for example, twelve fixing screws 9. If it does so, the holding | maintenance of the windshield 7 will be obtained in the form which block | closed the opening of the front panel 6. FIG.

At this time, a groove is further formed in the grooved portion of the opening of the front panel 6 where the stepped portion of the windshield 7 comes into contact. As shown in FIG. 10 is inserted.
Therefore, when the windshield 7 is held in the opening of the front panel 6, the O-ring 10 is deformed into a crushed shape between the front panel 6 and the windshield 7 as shown in the figure to maintain airtightness. To do.

  Thus, the front panel 6 to which the windshield 7 is attached is attached to the flange 3 at the front end portion by a plurality of, for example, twelve fixing bolts 11. An O-ring 12 is interposed between the front panel 6 and the flange 3 so as to provide airtightness.

At this time, the front panel 6 is provided with a vent hole 13 at a lower part of the front panel 6 below the opening. The vent hole 13 is internally threaded and can be opened and closed by attaching and removing screws (small screws). Normally, as shown in the figure, the screw is screwed in and closed. Details will be described later.
Next, a rear panel 14 is attached to the flange 4 at the rear end portion. The rear panel 14 is made of a thick plate material having a desired strength, and as is apparent from FIG. It is fixed to.

  Therefore, when the camera / lens unit 2 is inserted into the housing body 1 as shown by an arrow A in FIG. 3 and pushed until the rear panel 14 comes into contact with the flange 4 at the rear end, the camera / lens unit 2 is inserted. Is positioned and held by a predetermined member on the inner surface of the housing body 1. If the rear panel 14 is fixed to the flange 4 by a plurality of, for example, twelve connecting bolts 15, the camera lens is incorporated in the housing body 1. The unit 2 can be accommodated.

Although not shown at this time, an O-ring is also provided at a portion where the flange 4 at the rear end and the rear panel 14 are in contact with each other.
Thereby, when the connecting bolt 15 is tightened and the flange 4 and the rear panel 14 are brought into close contact with each other, the O-ring is crushed and deformed, so that the airtightness between the flange 4 and the rear panel 14 can be kept perfectly.
At this time, the rear panel 14 is provided with two handles 16 on the left and right as shown.

These handles 16 facilitate the handling when the camera / lens unit 2 is inserted and accommodated in the housing body 1, and the same is true when the camera / lens unit 2 is taken out of the housing body 1. However, having two handles 16 makes it possible to work easily and safely.
At this time, the rear panel 14 is provided with a connector plug 17 for cable connection. Therefore, the connection between the camera / lens unit 2 and the external device can be performed, and the camera can be operated as a camera device.

In the case of the camera device according to the present invention, the housing is used in a state where nitrogen is filled in the housing. Here, in this embodiment, nitrogen is introduced into the housing body 1 at a desired pressure higher than atmospheric pressure. It is designed to be used by enclosing it.
For this reason, as shown in FIG. 3, the enclosure valve 18 and the relief valve 19 are provided in the rear panel 14, and correspondingly, as described above, the vent hole 13 is provided in the front panel 6. .

Here, first, the sealed valve 18 is a kind of check valve, for example, the same valve (screw diameter 8V1) used for a pneumatic tire (automobile tire), and a gas (nitrogen) in the housing body 1 is used. ) Function as a gas inlet when feeding in.
At this time, the vent hole 13 functions to release the gas already present in the housing body 1 when the gas is introduced from the sealing valve 18.
Next, the relief valve 19 is a so-called safety valve, and when the pressure of the gas in the housing body 1 exceeds a preset pressure (relief pressure), the relief valve 19 opens to release the gas to the outside.

Here, regarding the positional relationship between these valves, first, as described above, the vent hole 13 is provided in the front panel 6, while the sealed valve 18 is provided in the rear panel 14. Is provided at a position farthest in the horizontal direction in the housing body 1.
At this time, as shown in FIG. 1, the vent hole 13 is provided at the lowermost portion of the front panel 6, while the sealing valve 18 is provided on the rear panel 14 as shown in the figure. They are provided at the uppermost part, and therefore, they are provided at the farthest positions in the housing body 1 even in the vertical direction.

By the way, in this embodiment, as shown in FIG. 1, an iris adjustment hole 20 is provided on the side surface of the housing body 1.
As shown in the figure, the iris adjustment hole 20 is normally closed by screwing a predetermined closing member. Details of the iris adjustment hole 20 will be described later.
In the case of the camera device according to the present invention, as described above, it is used in a state in which the housing is filled with nitrogen. In this case, usually, the camera device is installed in a desired imaging location, For example, it is attached to a semi-fixed or electric camera head.

At this time, the handle 16 described above functions to easily attach and detach the camera device to the camera platform.
After the attachment, the housing body 1 is filled with nitrogen. Here, the filling of the nitrogen is performed by a flexible tube such as a rubber hose having a desired connection base. Is generally carried out by supplying nitrogen from a portable container (nitrogen container) such as a cassette cylinder.

At this time, it is necessary to discharge the air in the housing simultaneously with the nitrogen injection.
For this reason, the sealing screw of the vent hole 13 is removed, the vent hole is opened, and the connection base of the tube connected to the nitrogen container is fitted into the sealing valve 18.
In this embodiment, the same valve as the valve (screw diameter 8V1) used for the pneumatic tire is used as the sealed valve 18, so that the base for connection corresponds to the valve used for this pneumatic tire. May be used.

When the valve of the nitrogen container is opened, the valve of the sealing valve 18 is opened by the pressure of nitrogen, so that nitrogen enters the housing body 1 and air in the housing body 1 passes along with this. It is pushed out from the pore 13.
At this time, nitrogen is lighter than air, and the sealing valve 18 is located on the upper side of the rear panel 14, as is apparent from FIG. It is at the bottom of the panel 6 and the air is heavier than nitrogen.

For this reason, the nitrogen that has entered the housing body 1 mainly flows upward, whereas the air that has been inside flows mainly under the housing body 1 and is pushed out of the vent hole 13. Therefore, the replacement of air with nitrogen in the housing body 1 is rational, and as a result, an increase in the nitrogen concentration in the housing body 1 can be obtained efficiently.
Therefore, after the vent hole 13 is kept open for a desired fixed time, the vent hole is closed by attaching a sealing screw to the vent hole 13 while supplying nitrogen.

At this time, since the pressure of nitrogen in the nitrogen container is considerably higher than atmospheric pressure, it is normally supplied through a pressure reducing valve. However, if nitrogen is still supplied with the vent hole 13 closed, The pressure of nitrogen in the main body 1 will rise until it exceeds atmospheric pressure and finally balances with the pressure of nitrogen in the nitrogen container.
Therefore, the rear panel 14 is provided with a relief valve 19 as shown in FIG.

When the relief pressure 19 reaches a relief pressure (desired pressure set in advance), the valve opens to release the gas (nitrogen) in the housing body 1 to the outside atmosphere. As a result, The pressure of nitrogen in the housing body 1 is in an equilibrium state with the relief pressure.
Therefore, if the operation of the relief valve 19 is confirmed and the valve of the nitrogen container is closed here, the pressure of nitrogen in the housing body 1 can be made the same as the relief pressure.

At this time, the relief valve generates a specific operation sound (for example, a sound that sounds like “hue”) due to the escape of gas when operated.
Therefore, if the operation sound of the relief valve is heard from the relief valve 19, it is sufficient to close the valve of the nitrogen container, and the pressure of nitrogen in the housing body 1 can be easily and easily made the same as the relief pressure. it can.
At this time, if a relief valve with a whistle is used, it is possible to generate a larger operating sound (for example, a sound that sounds “beep”).

Here, the operating conditions in nitrogen filling at this time will be described.
First, in the case of the camera device according to this embodiment, it is assumed that the internal volume of the housing body 1 is about 16 L (liters).
At this time, the supply pressure of nitrogen is 55 kPa, and nitrogen is supplied at a flow rate of 10 L / min for 8 minutes or more.
Then, since the internal volume of the housing main body 1 is about 16L at this time, if nitrogen of 80 L or more is supplied into the housing main body 1, the nitrogen concentration in the housing main body 1 is about 99% in calculation.

Therefore, nitrogen is supplied for 8 minutes or more under the above conditions, and after confirming the operation of the relief valve 19, a sealing screw is fitted into the vent hole 13, and the vent hole 13 is closed.
After that, if the connection base that has been fitted to the sealed valve 18 is removed, the valve of the sealed valve 18 is closed by the internal pressure, so that the filling of the housing main body 1 with nitrogen can be completed here. .

Next, the pressure of nitrogen filled at this time will be described.
In the present invention, the reason why the internal pressure of the housing body is kept higher than the atmospheric pressure is to prevent the entry of dust and foreign matters from the outside.
Therefore, the internal pressure of the housing body must be kept at a desired pressure higher than the atmospheric pressure, for example, 34.5 kPa, in the operating environment of the camera device.

At this time, since the volume of nitrogen changes depending on the temperature, the pressure changes depending on the temperature in the sealed container.
Here, assuming that the temperature in the use environment of the camera device (use environment temperature) is −25 ° C. to + 50 ° C., in order to always maintain the pressure of 34.5 kPa in this temperature range, − A pressure of 34.5 kPa is required at the lowest temperature of 25 ° C. For this purpose, it is necessary to maintain a pressure of 50 kPa at room temperature.

Therefore, in this embodiment, a relief valve 19 having an operating pressure (relief pressure) set to 50 kPa is used, and nitrogen is supplied at a pressure of 55 kPa as described above.
The operation of the relief valve 19 confirms that the nitrogen pressure has reached 55 kPa, and the nitrogen filling operation is terminated.

  Further, in this embodiment, in correspondence with the assumption that the operating environment temperature of the camera device is −25 ° C. to + 50 ° C., in this embodiment, the sealed valve 18 and the relief valve 19 have a temperature of −25 ° C. to + 50 ° C. A material that can withstand a sufficiently required function in a range, for example, a valve, a gasket, or a packing made of a material such as silicon rubber (fluorosilicon rubber) is used.

Further, in this embodiment, when the camera device is installed, the inside of the housing body 1 is maintained at a pressure of 50 kPa, so that the windshield 7 fitted in the opening of the front panel 6 is indicated by an arrow F in FIG. Force is applied from the direction shown.
For example, in this embodiment, since the area of the windshield 7 is 2000 mm ² , if the pressure is 50 kPa, a force of 980 N (100 kgf) is applied to the windshield 7 in the direction of arrow F.

As a result, the O-ring 12 interposed between the front panel 6 and the flange 3 is pressed against the front panel 6 with a force of 980 N applied through the windshield 7 and crushed. The airtightness between the windshields 7 is improved, which can greatly contribute to maintaining reliability.
In the case of this embodiment, flanges 3 and 4 of thick plate members are provided at the end of the housing body 1, and so-called flanges in which a front panel 6 and a rear panel 14 of the same thick plate member are respectively attached thereto. Mounting is used.

As a result, a sealing structure using an O-ring can be applied between the flanges 3 and 4 and the front panel 6 and the rear panel 14. Therefore, this also contributes to the improvement of the airtightness of the housing body 1 and greatly maintains the reliability. Can contribute.
At this time, it goes without saying that these O-rings are also made of a material that can sufficiently withstand a function that is sufficiently required even in a temperature range of −25 ° C. to + 50 ° C., such as silicon rubber.

Here, the iris adjustment hole 20 will be described.
In general, in a camera device, some adjustment may be required for the camera device after it is installed at a desired location.
Also in this embodiment, when the camera / lens unit 2 is housed in the housing main body 1 to form a camera device and the camera device is attached to a camera head installed at a desired image pickup location, the image pickup device according to the image pickup conditions at that location is used. Some adjustments may be required for the camera / lens unit 2.

In this case, in order to adjust the camera / lens unit 2, the camera / lens unit 2 must be removed from the housing body 1.
However, when the camera device is installed in a surveillance system, it is usually a high place where human hands cannot reach. Therefore, the adjustment is performed on a base with a poor foothold. Therefore, in this case, if the camera / lens unit 2 has to be taken out from the housing body 1, the adjustment is inevitably difficult.

By the way, the adjustment in this case is typically an iris adjustment.
Therefore, in this embodiment, as shown in FIG. 1, an iris adjustment hole 20 is provided on the side surface of the housing body 1, and at this time, the position of the iris adjustment hole 20 is the position of the camera / lens unit 2 housed in the interior. Therefore, according to this embodiment, the camera / lens unit 2 can be removed by removing the lid member and opening the iris adjustment hole 20 as necessary. It is possible to easily adjust the iris without taking it out of the housing body 1.

Then, after this iris adjustment, the lid member is screwed to close the iris adjustment hole 20 and the above-described nitrogen filling is performed, so that the installation of the camera device is completed and can be used.
When the filling of nitrogen is completed, a stopper member is attached to the relief valve 19 to prevent nitrogen from being released from the relief valve 19 when the operating environment temperature is equal to or higher than normal temperature.

According to this embodiment, since the positional relationship between the sealing valve 18 and the exhaust vent 13 is rationalized, when the housing body 1 is filled with nitrogen, the replacement of the injected nitrogen with the discharged air is smooth. At this time, the pressure of the enclosed nitrogen can be recognized by the operating sound of the relief valve 19, so that the nitrogen pressure in the housing body 1 can be managed easily and accurately.
Therefore, according to this embodiment, the pressure of nitrogen enclosed in the housing body 1 can always be kept at 34.5 kPa or more and below the pressure that is not likely to cause deformation of the housing body 1. It is possible to reliably provide a highly reliable camera device that reliably suppresses intrusion of a foreign substance.

  The camera device according to the present invention can be applied regardless of the field as a camera device to be used outdoors because there is no possibility of condensation on the windshield and no possibility of lowering reliability due to intrusion of dust.

1 Housing body 2 Camera / lens unit 3 Flange (front end flange)
4 Flange (Rear end flange)
5 Cover 6 Front Panel 7 Windshield 11 Fixing Bolt 13 Vent Hole 14 Rear Panel 15 Connection Bolt 16 Handle (Handle)
17 Connector plug (camera cable connection plug)
18 Enclosed valve 19 Relief valve 20 Iris adjustment hole

Claims (1)

Using a housing body provided with flanges for panel mounting on one and the other end face of a cylindrical metal case having a substantially square cross section,
One end face of the housing body is sealed by flange attachment via an O-ring of a front panel provided with a windshield, and the other end face is flanged via an O-ring of a rear panel provided with a connector plug for camera cable connection. In the camera device of the system that is sealed by mounting and used with nitrogen enclosed in the state where the camera lens unit is housed inside,
It has an openable / closable vent hole, a sealed valve made up of a check valve, and a relief valve that operates at a preset desired relief pressure,
The camera is characterized in that the vent hole is provided at a lower end portion of the front panel, the sealed valve is provided at an upper end portion of the rear panel, and the relief valve is provided at a lower end portion of the rear panel. apparatus.