JPH02134519A - Liquid-level gage - Google Patents

Abstract

PURPOSE:To make it possible to ensure detection by projecting light to a liquid surface at a specified angle from a light projection means, and displaying the position of the liquid surface by a liquid surface display means based on the presence or absence of the light reflected from the liquid surface. CONSTITUTION:The light which is emitted from a light source 9 is aligned to some extent through an optical fiber cable 10. Thereafter, the light is guided to the inside of a glass tube 4 through an incident port 11. The incident angle of said light beam with respect to a liquid surface 2a is set sufficiently large. The light beam directly reaches the liquid surface, or the light is reflected with reflectors 12 and then reaches the liquid surface 2a. The light beam which has reaches the liquid surface 2a is totally reflected with the liquid surface 2a and does not enter into the liquid. The light beam is inputted at certain angle with respect to the radial direction of the glass tube 4. When the reflection from the reflectors 12 is repeated, the spreading is increased. The light finally reaches a screen 13. In this way, only the side of the screen 13 on which the light is inputted is illuminated with the liquid surface 2a as a boundary. When the screen is viewed through an opening part 7, the position of the liquid surface 2a can be definitely known based on the difference between the bright and dark parts of the screen 13.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid level gauge provided for monitoring the level of liquid in a container from the outside.

[Conventional technology]

Figure @5 is, for example, Sugihara Keiki's instrument catalog No. 87 (
(Published January 1987), page 145, shows a front view showing the schematic configuration of a conventional liquid level gauge. Figure 6 is cross section B in Figure 5.
It is a sectional view showing -B. In fig.

(1) is the container, (2) is the liquid level in the container (1), (3) is the metal protection tube, (4) is the protection tube (3)
The glass tube (5) is a communication tube that connects the inside of the container (1) and the glass tube (4), and (6) is the protective tube (3).
), (7) is the opening of the protection tube (3), (8) is the open hole that opens the inside of the glass tube (4) to the atmosphere, (2a) is the inside of the glass tube (4). It is the liquid level.

Next, we will explain the operation.〇The liquid in the container (1) passes through the connecting pipe (5) and the glass tube (
4) The liquid level (
2) and the liquid level (2a) in the glass tube (4) are the same. Therefore, the liquid level (2a) in the glass tube (4) is lowered from the opening (c) of the protection tube (3) to the glass tube (c).
4), the level of the liquid in the container (1) can be determined. Also, set the liquid level (2a) to the scale (6
) The liquid level can be quantitatively grasped by comparing with the It is necessary to connect to the gas phase section of the

Also, as a matter of course, in order to see the liquid level, external light needs to be incident through the opening (7).

[Problem to be solved by the invention]

Conventional liquid level gauges are constructed as described above, so if the liquid is colorless and transparent, or close to it, the liquid level will be low.Also, even at night or indoors, no one can enter and TV cameras, etc. External lighting is necessary for remote monitoring, especially when using a television camera for remote monitoring.

There were problems such as the liquid level being difficult to understand and making it even more difficult to know the position of the liquid level.

This invention was made to solve the above-mentioned problems, and aims to provide a liquid level gauge that can clearly display the liquid level even in the case of colorless and transparent liquids. Means for Solving the Problem] The liquid level gauge according to the present invention includes a cylindrical body that is attached to a container containing a liquid and allows the liquid in the container to be guided to the same level as the inside of the container, and a liquid level of the liquid in the cylindrical body. A light input means for inputting light at a predetermined angle.

A liquid level display means is provided which displays the position of the liquid level based on the presence or absence of light that enters from the light input means and is reflected by the liquid surface of the liquid inside the cylindrical body. The meter uses a liquid level display means to display the position of the liquid level based on the presence or absence of light that is incident on the liquid surface at a predetermined angle by the light incident means and reflected by the liquid surface.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings.0 Fig. 1 is a front view showing a schematic configuration of a liquid level gauge according to an embodiment of the present invention, and Fig. 2 shows a cross section A-person in Fig. 1. FIG. In the figure, (1) to (8) are the same as the conventional one. (9) is a light source.

αO is light i! i (9) is an optical fiber cable that guides the light into the glass tube (4), αD is the entrance of the light guided by the optical fiber cable αO into the glass tube (4).

Light is made incident on liquid 1 (2a) at a predetermined angle.

(2) is a reflector that reflects the light incident from the entrance α°C, and αj is a screen. Note that the second reflector (2) is located at the top of the glass tube (4) and the side surface of the glass tube (4).
It is provided around the entire circumference except for the part where the opening (7) and the screen αj are provided.

Further, FIGS. 3 and 4 are explanatory diagrams for explaining the operation of the liquid level gauge of the first cause, and α4 represents the light incident into the glass tube (4) from the entrance port αB.

In the liquid level gauge configured as above, the light source (9)
The light emitted from the glass tube (4) is guided into the glass tube (4) from the entrance αB after its direction is aligned to some extent by the optical fiber cable 00. The liquid level of this ray α (2
The angle of incidence with respect to a) is set sufficiently large, and the fourth
As shown in the figure, the light ray 04 that reaches the liquid surface (2a) either directly or by being reflected by the reflector (2) is totally reflected by the liquid surface (2a) and moves toward the liquid surface. I never go into it. In addition, as shown in Figure 3, the light ray α is incident at a certain angle with respect to the radial direction of the glass tube (4), and as it is repeatedly reflected by the first reflector (2), its spread is 0 In this way, the screen (to) is illuminated only on the side where the light enters, with the liquid level (2a) as the boundary, and when viewed through the opening (7), the screen (to) is illuminated. (to) due to the difference in brightness of the liquid level (2a
) The position of the screen IJ-n (
However, the weaker the light from the outside, the more clearly the position of the liquid level (2a) can be displayed in the liquid level gauge. is incident on the gas side.

The light may be incident on the liquid side.

Alternatively, the light can be ultraviolet rays and the screen can be a fluorescent material.

Furthermore, if a light source containing infrared rays is used, monitoring with an infrared camera is also possible.Also, photosensitive elements are arranged on the edges of the screen.

By extracting the liquid level as an electrical signal.

Can be used as a level detector〇 In addition, a lens is used to provide a light source to the liquid level gauge.

Although it is possible to guide external light into the level gauge using an optical fiber, it is better to provide a light source in the level gauge than to provide external lighting, but it consumes less power. [Effects of the Invention] As described above, according to Hakumei, a liquid level gauge is a cylindrical body that is attached to a container containing liquid and that allows the liquid in the container to be guided to the same liquid level as the inside of the container. A light incidence means for making light enter at a predetermined angle with respect to the surface of the liquid in the cylindrical body; Since the structure is equipped with a liquid level display means for displaying the position, even if the liquid is colorless and transparent.

It has the effect of providing a product that can reliably display the liquid level and can be used in places with little external light, such as at night.

[Brief explanation of the drawing]

Fig. 1 is a front view showing a liquid level gauge according to one embodiment of Seimei, Fig. 2 is a sectional view taken along section A-A in Fig. 1, and Figs. An explanatory diagram for explanation, Figure 5 is a front view showing a conventional liquid level gauge, and Figure @6 is a cross section B of Figure 5.
- In figure 0, which is a cross-sectional view showing B, (1) is a container, (2), (2a) are liquid levels, (3) is a protection tube, (4) is a glass tube, (5) is a communication tube, (9) is the light source, QO is the optical fiber cable, α
B is a light entrance, a2 is a reflector, and a3 is a screen. Note that the same symbols in each figure indicate the same or equivalent parts.

Claims (1)

[Claims] a cylindrical body that is attached to a container containing a liquid and guides the liquid in the container to the same liquid level as the inside of the container; a light incidence means that makes light incident at a predetermined angle with respect to the liquid level in the cylindrical body;
A liquid level gauge comprising a liquid level display means for displaying the position of the liquid level based on the presence or absence of light incident from the light input means and reflected by the liquid surface of the liquid inside the cylindrical body.