JPH0980605A - Explosion-proof industrial monitor camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make focus adjustment possible in a dangerous atmosphere by providing a focus adjusting means that can adjust focus while holding the explosion-proof state of an explosion-proof container. SOLUTION: A camera 1a and a shaft 8 are installed in an explosion-proof container 2a, and a shaft 9 is installed piercing the wall of the explosion-proof container 2a while holding the explosion-proof state of the explosion-proof container 2a. One side of a belt 7 is hung around a focus adjusting ring of the camera 1a, and the opposite side of the belt 7 is hung around one end of the shaft 8. The other end of the shaft 8 and one end of the shaft 9 are meshed through a gear or the like, and a focus adjusting screw 10 is provided at the other end of the shaft 9. When the focus adjusting screw 10 is rotated by a tool such as a driver, the shaft 9 is rotated, and the shaft 8 meshed with the shaft 9 is also rotated. This rotatory driving is transmitted through the belt 7 to rotate the focus adjusting ring of the camera 1a, so that the focal length of the camera 1a is changed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an explosion-proof industrial surveillance camera used in a hazardous area such as a process plant,
Particularly, the present invention relates to an explosion-proof industrial surveillance camera that can be adjusted in focus in a dangerous atmosphere and can be easily wired.

[0002]

2. Description of the Related Art When a surveillance camera is installed in a place such as a process plant where explosive gas or vapor is present, an explosion-proof structure is adopted to prevent an explosion or a fire caused by the surveillance camera.

FIG. 2 is a plan view showing an example of such a conventional explosion-proof industrial surveillance camera. In FIG. 2, 1 is a camera, 2 is an explosion-proof container, 3 is a terminal box, 4 is a terminal block, and 5 and 6 are wiring cables.

The camera 1 is installed inside the explosion-proof container 2, and the wiring cable 5 from the camera 1 is wired to the terminal block 4 provided in the terminal box 3. The wiring cable 6 is externally inserted into the terminal box 3 while keeping the explosion-proof state, and connected to the terminal block 4.

With such a structure, it is possible to prevent the operation of the camera 1 and the occurrence of an explosion or fire caused by a spark or the like generated in the terminal block 4.

[0006]

However, in the conventional explosion-proof industrial surveillance camera, a lens according to the application is properly attached to the "a" portion of the camera 1, but in general, such focus adjustment is not necessary. It is manual. Therefore, in a non-hazardous atmosphere such as when the operation of the process plant is stopped, the focus of the lens is adjusted in advance, and then the operation of the process plant is restarted. That is, there is a problem that the focus cannot be readjusted at the installation location even if the monitoring target is changed during the operation of the process plant.

In addition, in the case of wiring in the conventional example, the cover of the terminal box 3 is removed, the wiring cable 6 is inserted from the wiring openings shown in "b" and "c" in FIG. However, there is a problem that the wiring work is complicated because it must be connected to the terminal block 4. Therefore, an object of the present invention is to realize an explosion-proof industrial surveillance camera capable of focusing in a dangerous atmosphere and easily wired.

[0008]

In order to achieve such an object, according to the first aspect of the present invention, in an explosion-proof industrial surveillance camera used in a dangerous atmosphere, an explosion-proof container and an inside of the explosion-proof container are provided. A camera having a focus adjusting function, a shaft fixed to a focus adjusting screw provided outside the explosion-proof container and transmitting the rotational movement of the focus adjusting screw inside the explosion-proof container, and a rotary motion of this shaft. And a focus adjusting unit including a belt for transmitting to the focus adjusting function of the camera.

According to a second aspect of the present invention, in an explosion-proof industrial surveillance camera used in a dangerous atmosphere, a rear cover attached to the explosion-proof container and provided between the explosion-proof container and the rear cover is provided from the inside of the explosion-proof container. A first connector to which the wiring is connected, a second connector having an outer diameter smaller than the diameter of the wiring port of the rear cover and connected to the first connector, and the second connector It is characterized by comprising a connected wiring cable and a plug for holding the wiring cable and attached to the wiring port of the rear cover.

[0010]

By providing the focus adjusting means capable of adjusting the focus while maintaining the explosion-proof state of the explosion-proof container, the focus of the camera can be adjusted even in a dangerous atmosphere. Further, by making the diameter of the wiring port of the rear cover larger than the outer diameter of the connector, the terminal treatment at the installation place becomes unnecessary.

[0011]

The present invention will be described in detail below with reference to the drawings.
FIG. 1 is a configuration plan view showing an embodiment of an explosion-proof industrial surveillance camera according to the present invention. In FIG. 1, 1a is a camera having a focus adjustment function, 2a is an explosion-proof container, 7 is a belt, and 8
Reference numerals 9 and 9 are axes, 10 is a focus adjusting screw, 11 and 12 are connectors, 13 is a rear cover, 14 is a stopper, 15 and 16 are wiring cables, and 17 is a composite cable.

However, the wiring port of the rear cover 13 is shown in FIG.
The diameter of the middle "A" portion is larger than the outer diameter of the connector 12. Further, 7 to 10 constitute a focus adjusting means 50.

The camera 1a and the shaft 8 are installed inside the explosion-proof container 2a by means not shown, and the shaft 9 is installed through the wall of the explosion-proof container 2a while maintaining the explosion-proof state of the explosion-proof container 2a. One side of the belt 7 is hung around the focus adjustment ring of the camera 1a, and the other side of the belt 7 is hung around one end of the shaft 8.

The other end of the shaft 8 and one end of the shaft 9 are meshed with each other by a gear or the like, and a focus adjusting screw 10 is provided at the other end of the shaft 9. The wiring cable 15 of the camera 1a is connected to the connector 11.

A plug 14 is attached to the rear cover 13, and a composite cable 17 from the outside passes through the inside of the plug 14. Once inside the rear cover 13, the composite cable 17 is divided into wiring cables 16 which are connected to the connector 12.

Further, the rear cover 13 is attached to the explosion-proof container 2a while connecting the connector 12 and the connector 11.

The operation of the embodiment shown in FIG. 1 will be described. When the focus adjusting screw 10 is rotated by a tool such as a screwdriver, the shaft 9 rotates, and the shaft 8 meshing with the shaft 9 also rotates. This rotational movement is transmitted by the belt 7,
Since the focus adjustment ring of the camera 1a rotates, the focal length of the camera 1a changes.

As a result, by providing the focus adjusting means 50 capable of adjusting the focus while maintaining the explosion-proof state of the explosion-proof container 2a, the focus of the camera 1a can be adjusted without touching the camera 1a even in a dangerous atmosphere. become.

Further, the rear cover 13 shown by "a" in FIG.
Since the diameter of the wiring port of is larger than the outer diameter of the connector 12, the connector 12 to which the wiring cable 16 has already been attached is inserted from the wiring port of the rear cover 13 shown in FIG. After connecting and
By attaching the rear cover 13 to the explosion-proof container 2a and further attaching the stopper 14, the wiring work at the installation site becomes easy.

As a result, by making the diameter of the wiring port of the rear cover 13 larger than the outer diameter of the connector 12, the terminal treatment at the installation place is unnecessary and the wiring work becomes easy.

The focus adjusting means 50 is not limited to this structure, of course, and the explosion-proof container 2 is extended by extending the shaft 8 in the direction of "b" in FIG.
A configuration in which a focus adjusting screw is provided by penetrating the wall a may be used. That is, one shaft 8, belt 7 and focus adjusting screw 1
It can be configured from zero.

In the embodiment shown in FIG. 1, one connector 12 is used for the sake of simplicity, but wiring can be facilitated even if a plurality of connectors are used. That is, if the outer diameter of each of the plurality of connectors is smaller than the diameter of the wiring port of the rear cover 13, the already wired connectors are sequentially connected to the wiring port of the rear cover 13 by adjusting the wiring cable length. Since it can be passed, no terminal treatment is required at the installation site, and wiring is easy.

[0023]

As is apparent from the above description,
The present invention has the following effects. According to the invention of claim 1, the explosion-proof industrial surveillance camera capable of adjusting the focus in a dangerous atmosphere can be realized by providing the focus adjusting means for adjusting the focus while keeping the explosion-proof state of the explosion-proof container.

According to the second aspect of the present invention, by making the diameter of the wiring port of the rear cover larger than the outer diameter of the connector to be inserted, an explosion-proof industrial surveillance camera with easy wiring can be realized.

[Brief description of drawings]

FIG. 1 is a configuration plan view showing an embodiment of an explosion-proof industrial surveillance camera according to the present invention.

FIG. 2 is a plan view showing an example of a conventional explosion-proof industrial surveillance camera.

[Explanation of symbols]

 1,1a Camera 2,2a Explosion-proof container 3 Terminal box 4 Terminal block 5,6,15,16 Wiring cable 7 Belt 8,9 Axis 10 Focus adjustment screw 11,12 Connector 13 Rear cover 14 Plug 17 Composite cable 50 Focus adjustment means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (71) Applicant 000006507 Yokogawa Electric Co., Ltd. 2-9-32, Nakamachi, Musashino-shi, Tokyo (74) Attorney Masaya Watanabe (72) Inventor Norio Matsudaira Osaka 3-3-22 Nakanoshima, Kita-ku, Osaka-shi, Kansai Electric Power Co., Inc. (72) Inventor Shoichi Matsuoka, 3-3-22 Nakanoshima, Naka-ku, Kita-ku, Osaka-shi, Osaka (72) Inventor Masanobu Nagao 3-6-26 Tenjinbashi, Kita-ku, Osaka-shi, Osaka Prefecture Ogimachi Park Building, within Anan Electric Co., Ltd. (72) Inventor Akira Oya 2-932, Nakamachi, Musashino City, Tokyo Yokogawa Electric Co., Ltd. (72) Inventor Furuya Ryoki 2-9-32 Nakamachi, Musashino-shi, Tokyo Yokogawa Electric Co., Ltd. (72) Inventor Miwa Yanagawa 2-3-9, Nakamachi, Musashino-shi, Tokyo Yokogawa Electric Co., Ltd. The inner

Claims (2)

[Claims] 1. An explosion-proof industrial surveillance camera used in a dangerous atmosphere, comprising an explosion-proof container, a camera having a focus adjusting function provided inside the explosion-proof container, and a focus adjusting device provided outside the explosion-proof container. A focus adjusting unit, which is fixed to a screw and includes a shaft for transmitting the rotational movement of the focus adjusting screw inside the explosion-proof container, and a belt for transmitting the rotational movement of the shaft to the focus adjusting function of the camera, is provided. Explosion-proof industrial surveillance camera characterized by the following. 2. An explosion-proof industrial surveillance camera used in a dangerous atmosphere, wherein a rear cover attached to the explosion-proof container and a wire provided from inside the explosion-proof container are provided between the explosion-proof container and the rear cover. And a second connector having an outer diameter smaller than the diameter of the wiring port of the rear cover and connected to the first connector, and wiring connected to the second connector. An explosion-proof industrial surveillance camera comprising: a cable; and a stopper for holding the wiring cable and attached to a wiring port of the rear cover.