JPS6244630A - Remote monitor system for liquid level - Google Patents

Abstract

PURPOSE:To increase sufficiently the quantity of light indicating the height of a liquid level on a display part, and to make the display easy to see and make a precision observation with the naked eye of an operator by allowing LEDs of the display part to illuminate in response to color light from a light emission part and displaying the height of the liquid level. CONSTITUTION:Respective light emission units 2a in the ligth emission part 2 emit green light below the water level and red light above the water level according to the water level in a boiler drum 1. The green or red light of each unit 2a is guided by a fiber 3 and received and converted into an electric signal by a corresponding photodetecting element 4a in a photoelectric conversion part 4. Electric signals as photodetection outputs of respective elements 4a are inputted to respective driving circuits 6a in a driving part 6 and LEDs 5a in the display part 5 are driven with outputs of corresponding circuits 6a to illuminate. In this case, when the elements 4a of the conversion part 4 are sensitive to green light, elements 5a corresponding to units 2a which emit green light illuminates and other elements 5a do not illuminate. Then, the boundary between the illuminating elements 6a and other elements indicates the water level.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a liquid level remote monitoring system for monitoring the liquid level height of a liquid container such as a boiler drum at a location remote from the liquid container.

<Prior Art> In equipment that uses steam obtained from a boiler for various purposes, it is necessary to constantly and accurately check the water level in the boiler drum in a control room.

Conventionally, as a system for remotely monitoring the water level of a boiler drum in a control room, as shown in Fig. 1θ, a light emitting unit 2o that displays the water level in two colors is provided in the communication pipe 1ao of the boiler drum 1o. There is a device in which a large number of optical fibers 3o that receive colored light are installed facing each other in the section 20, the optical fibers 30 are laid down to a control room, and a display section 4o is formed by the terminal ends of the optical fibers in the control room. .

The light emitting unit 2o is formed by vertically arranging a large number of light emitting units 2ao each of which is a combination of a light source and a prism.
Each light emitting unit 2ao emits green colored light under the water surface and red colored light above the water surface by changing the refractive index depending on whether the prism part is immersed in water or not. It has become.

<Problems to be Solved by the Invention> In the conventional monitoring system described above, since the operator observes the colored light from the light emitting unit 2ao through the optical fiber 3o, the amount of colored light incident on the operator's naked eye is weak. This can make it difficult to see, leading to errors in water level observation.

In addition, a large number of optical fibers 30 are required to guide colored light, and the cable that bundles all of these optical fibers has a large diameter. It is difficult to bend and is inconvenient when installing.

Furthermore, the optical fiber itself is expensive, and in order to guide the optical fiber to the control room, a large number of long optical fibers are required, resulting in an increase in cost.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a liquid level remote monitoring system that has an easy-to-see liquid level display, is convenient to install, and can be implemented at low cost.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the present invention reduces the liquid level height to 2 by using a large number of light emitting units provided in the liquid container to be monitored.
a light emitting unit that displays colors; a photoelectric conversion unit that receives colored light from the light emitting unit directly or through an optical fiber and converts it into an electrical signal; and a light emitting unit that emits light in response to the electrical signal from the photoelectric conversion unit. A liquid level remote monitoring system is constructed by including a display section arranged in parallel in a manner corresponding to each light emitting unit in the light emitting section.

<Example> Hereinafter, the present invention will be described in detail based on an example shown in the drawings. FIG. 1 is a configuration diagram of a liquid level remote monitoring system which is an embodiment of the present invention. A light emitting unit 2 that displays two colors, a photoelectric conversion unit 4 that receives colored light from the light emitting unit 2 through an optical fiber 3°, and a display unit that performs display operations in response to electrical signals from the photoelectric conversion unit 4. 5, and a drive section 6 that drives the display section 5.

The boiler drum l is provided with a communication pipe 1a, and the light emitting section 2 is attached to the communication pipe 1a. The light-emitting section 2 has a large number of light-emitting units 2a that are a combination of a light source and a prism arranged vertically. By changing the refractive index, it emits green colored light below the water surface and red colored light above the water surface. Moreover, the starting end of the optical fiber 3 is
Each of them is attached to the light emitting section 2 by a hood 7 so as to face each light emitting unit 2a of the light emitting section 2.

Furthermore, the photoelectric conversion unit 4 includes the same number of light receiving elements 4a that are sensitive to either green color light or red color light as the number of the optical fibers 3, and the light receiving element 4a is sensitive to either green color light or red color light. The terminal end of the optical fiber 3 is optically connected to the surface. The display section 5 is provided in a location remote from the boiler drum 1, such as a control room, and includes a large number of light emitting elements 5a that emit light in response to electrical signals from each light receiving element 4a of the photoelectric conversion section 4; ...Or it is constructed by arranging light emitting means such as lamps in parallel.

Looking at each light emitting unit 2a of the light emitting section 2, as shown in the partial configuration diagram in FIG.
The light emitting elements 5a in the display section 5 correspond to each other, and the light emitting elements 5a in the display section 5 are vertically arranged in the same arrangement as the light emitting units 2a in the light emitting section 2. In FIG. 2, reference numeral 6a is a drive circuit that drives the corresponding light emitting element 5a in response to a signal from each light receiving element 4a.

In the above configuration, each light emitting unit 2a in the light emitting section 2
emits green colored light below the water surface and red colored light above the water surface, depending on the water level in the boiler drum i. Green or red colored light from each light emitting unit 2a is guided by an optical fiber 3, received by a corresponding light receiving element 4a in a photoelectric conversion section 4, and converted into an electrical signal. The electric signal that is the light reception output of each light receiving element 4a is input to each drive circuit 6a in the drive section 6, and the corresponding light emitting element 5a in the display section 5 emits light by the drive output of the drive circuit 6a.

Assuming that the light receiving element 4a in the photoelectric conversion unit 4 is sensitive to green color, the light emitting unit 2 that emits green colored light
The light emitting element 5a corresponding to a emits light, and the other light emitting elements 5a do not emit light. The boundary between the group of light emitting elements 5a that do not emit light and the group of light emitting elements 5a that emit light represents the water surface height.

In the above embodiment, the water level is displayed by the light emission and non-light emission of the light emitting element 5a, but as in each of the embodiments shown in FIGS. On the other hand, a large number of rows of two-color light-emitting means (lamps can be used, but in the following example, light-emitting elements) are provided, and the water level can be displayed in two colors by these light-emitting elements.

That is, in the second embodiment shown in FIG. 3, the colored light of each light emitting unit 2a is transmitted through two optical fibers 31a.

31b, the light receiving elements 4 each sensitive to green color light.
1a and a light receiving element 41b sensitive to red color light),
,,,isil! g□□4□a, 41b'? ? . The driving circuits 61a and 61b, which operate in the following manner, cause one of the light emitting elements 51a and 51b to emit light in a pair of two colors, each of which indicates the same water level.

In the third embodiment shown in FIG. 4, colored light from each light emitting unit 2a is received by a single light receiving element 4a through one optical fiber 3, and the light receiving output of the light receiving element 4a is detected by a level discrimination circuit 8.
The level discrimination circuit 8 discriminates whether green or red light is received by the light receiving element 4a, and the drive circuits 62a and 62b, which operate in response to the discrimination output, set the two colors at the same water level. Either one of the light emitting elements 52a and 52b, which indicates the following, is made to emit light.

In the fourth embodiment shown in FIG. 5, colored light from each light emitting unit 2a guided by an optical fiber 3 is divided into two parts by an optical demultiplexer 9. The branched color light is branched into a path, and the branched color light is guided to a light receiving element 43a sensitive to green color light and a light receiving element 43b sensitive to red color light, and operates in response to a light reception signal at each light receiving element 43a, 43b. The drive circuits 63a and 63b cause one of the light emitting elements 53a and 53b to emit light in a pair of two colors that indicate the same water level.

In this way, when a pair of two-color light-emitting means is associated with each light-emitting unit 2a of the light-emitting unit 2 in the display unit 5, the display unit 5
is divided into a group of light-emitting means that emits light in response to the green color light of the light-emitting unit 2a and a group of light-emitting means that emits light in response to the red color light of the light-emitting unit 2a, and there is a boundary between the two groups whose emission colors differ from each other. The liquid level height will be displayed.

In each of the first to fourth embodiments described above, the light emitting section 2
The colored light from the light emitting section 2 is introduced directly into the photoelectric conversion section 4 through the optical fiber 3, but as in the embodiments shown in the drawings from FIG. Good too.

The fifth embodiment shown in FIG. 6 includes a two-color display light emitting section 2 provided on the side of the boiler drum 1, a photoelectric conversion section 44 attached to this light emitting section 2, and an electric power output from the photoelectric conversion section 44. A display section 54 that performs a display operation in response to a signal, and the display section 5
The system includes a drive unit 64 that drives the drive unit 4.

The photoelectric conversion section 44 includes the same number of light receiving elements 44a that are sensitive to either green color light or red color light as each light emitting unit 2a of the light emitting section 2. The surface faces the light emitting surface of each light emitting unit 2a. Further, the display section 54 includes the photoelectric conversion section 44
A large number of light emitting means (
In this example, the light emitting elements 54a) are arranged in parallel, and as shown in the partial configuration diagram in FIG.
, each drive circuit 64a of the drive section 64 and each light emitting element 54a of the display section 54 correspond to each other. In this fifth embodiment, a light emitting element 54a that does not emit light in the display section 54
There is a group of light emitting elements 54a and a group of light emitting elements 54a that emit light, and the boundary between the two groups represents the water surface height.

In the fifth embodiment described above, the water level is displayed by light emission and non-light emission of the light emitting element 54a, but as in each of the embodiments shown in FIGS. On the other hand, a pair of two-color light-emitting means, such as a large number of light-emitting elements, are arranged in rows, and the water level can be displayed in two colors by these light-emitting elements.

That is, in the sixth embodiment shown in FIG. 8, the colored light of each light emitting unit 2a is transmitted through a pair of light receiving elements 45a, a light receiving element 45a sensitive to green color light and a light receiving element 45b sensitive to red color light. , 45b, each of the light receiving elements 45a, 45
a drive circuit 65a that operates in response to the light reception signal at b;
65b, the light emitting element 55a shows the same water level in a pair of two colors.
, 55b is made to emit light.

In the seventh embodiment shown in FIG. 9, colored light from each light emitting unit 2a is received by a single light receiving element 46a, and the light receiving output of the light receiving element 46a is introduced into a level discrimination circuit 86. The light-receiving element 46a determines whether green or red light is received, and drive circuits 66a and 66b that operate in response to the output of the determination cause one of the light-emitting elements 56a and 56b to exhibit the same water level in a pair of two colors. It is designed to emit light.

<Effects of the Invention> As described above, according to the present invention, a light emitting device such as a light emitting element or a lamp emits light in the display section in response to colored light from the light emitting section to display the liquid level height. The amount of light indicating the liquid level height at the point is sufficiently large, the display is easy to see, and the operator can accurately observe with the naked eye.

In addition, because the colored light from the light emitting part is converted into an electrical signal by a photoelectric conversion part on or near the light emitting part and transmitted to a display part located at a remote location, it is not necessary to bundle a large number of optical fibers as in the past. There is no need to install the system over a long distance, and the system is easy to install and can be implemented at low cost.

[Brief explanation of drawings]

1 to 9 relate to embodiments of the present invention; FIG. 1 is an overall configuration diagram of the first embodiment, FIG. 2 is a partial configuration diagram thereof, and FIG. 3 is a part of the second embodiment. 4 is a partial configuration diagram of the third embodiment, FIG. 5 is a partial configuration diagram of the fourth embodiment,
FIG. 6 is an overall configuration diagram of the fifth embodiment, and FIG. 7 is a diagram of the fifth embodiment.
FIG. 8 is a partial diagram of the sixth embodiment, FIG. 9 is a partial diagram of the seventh embodiment, and FIG. 1O is a diagram of the conventional example. l... Boiler drum, 2... Light emitting part, 2a...
Light emitting unit, 3... Optical fiber, 4.44... Photoelectric conversion section, 5.54... Display section, 6.64... Drive section. Figure 1 Figure 3 Figure 5

Claims (1)

[Claims] (1) A light-emitting unit installed in a liquid container to be monitored, in which a number of light-emitting units that emit light of different colors below and above the liquid surface of the liquid container are vertically arranged, and a light-emitting unit that emits light of each color from the light-emitting units. A photoelectric conversion section that receives light directly or through an optical fiber and converts it into an electrical signal, and a light emitting means that emits light in response to the electrical signal from the photoelectric conversion section, in a form corresponding to each light emitting unit in the light emitting section. A liquid level remote monitoring system characterized by comprising a parallel display section.