JPS60114716A - Apparatus for detecting amount of remaining liquid in tank - Google Patents

Abstract

PURPOSE:To improve usability, by forming windows, whose reflectivities of light is different based on the difference in refractive indexes between the liquid and gas, from the upper part to the lower part of a tank, and displaying the liquid level in correspondence with the regions of intensity of the reflected lights from said windows. CONSTITUTION:Photodiodes 14 projects light to windows 12 from the upper part to the lower part of a tank. Therefore phototransistors 15 located at the part higher than the liquid level receive the intense reflected light and their resistances become small. Meanwhile, the phototransistors 15 lower than the liquid level 15 receive the weak reflected light, and their resistances remain large. Therefore, only a small current flows through each display lamp 8, which is in parallel with the phototransistor 15 receiving the intense reflected light, and the lamp is OFF. Meanwhile, a large current flows through the display lamp 18, which is in parallel with a phototransistor 15 receiving only the weak reflected signal, and the lamp is ON.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a device for detecting the remaining amount of liquid in a tank, such as a liquid fuel tank.

<Prior Art> Conventionally, the remaining amount of fuel in a portable liquid fuel tank 2 provided in, for example, an oil combustor 1 has been detected as shown in FIG.

As shown in FIG. 2, the amount of fuel in the liquid fuel tank 2 is detected through the remaining amount detection window 3 formed at the bottom of the liquid fuel tank 2 and the inspection window 4 formed at the bottom of the main body of the oil combustor 1. It was visible.

However, with the conventional detection configuration described above, it is not easy to constantly look into and monitor the inspection window 4 because it is located at a low position.Furthermore, it is not possible to know the remaining level of the upper level of the inspection window 4. It was inconvenient.

<Summary of the Invention> The present invention has been made in view of the above points, and a window is formed from the top to the bottom of the tank with different reflectance of light due to the difference in refractive index between liquid and gas. If the liquid level is displayed according to the intensity of the light reflected from the window, then K
The purpose of this invention is to solve the above-mentioned conventional inconveniences.

<Embodiment of the Invention> An embodiment of the present invention will be described below with reference to FIGS. 3 to 6.

In the figure, 11ill is a tank such as a liquid fuel tank installed in an oil combustor, etc., and 12 is a tank extending from the top to the bottom of the tank 11, and has an uneven back surface so that the liquid adheres to the tank and reduces the counterweight. 13 is a sensor section disposed opposite to the window 12;
Pairs consisting of a light emitting diode 14 and a phototransistor 15 that emit light of a specific wavelength are arranged at a plurality of locations so as to detect reflected light from a plurality of locations from the top to the bottom of the device. Each of these light emitting diodes 14 is connected to a DC power source 1.
The phototransistors 15 are connected in series to the light emitting diode 14, and the phototransistors 15 and the current limiting resistor 17 are connected in parallel to each other and further in parallel to the light emitting diode 14 to a DC power source 16. 18
is an indicator lamp connected in parallel to each phototransistor 15, which is turned on when the reflected light from the window 12 is weak and the resistance of the phototransistor 15 is large.

The current limiting resistor 11 is set to such a value that even if the resistance of the shift transistor 15 decreases due to the reflected light from the window 12, the intensity of light emitted by the light emitting diode 140 hardly changes.

Next, the effect will be explained.

Since each light emitting diode 14 illuminates the window 12 from the top to the bottom, for example, if there is a liquid level in the tank 11 as shown in FIG. 5, the phototransistor 15 above the liquid level will have a strong reflection. The phototransistor 1 receives light and has a small resistance, but is below the liquid level.
5 is a weak reflected light, so it remains a large resistance.

Therefore, the display lamp 18 parallel to the phototransistor 15 that receives strong reflected light only has a small current flowing through it and remains in the off state, while the display lamp 18 parallel to the phototransistor 15 that receives only weak reflected light A large current flows and the light is on.

An example of this liquid level display is shown in FIG. In this figure, levels I and E are in the lit state.

<Effects of the Invention> As explained above, according to the present invention, there is a window extending from the top to the bottom of the liquid storage tank and whose weight changes depending on the close contact of the liquid, and a window extending from the top to the bottom of the window. means for emitting light throughout the tank; display means for displaying the liquid level in the tank by detecting light reflected by the window at multiple points from the top to the bottom of the window; Since it is a remaining amount detection device, the remaining amount of liquid in the tank can be displayed continuously without contact, improving usability, and
It also has excellent reliability because it does not use electrical contacts.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a conventional tank, FIG. 2 is a perspective view of an oil combustor incorporating the same tank, FIG. 3 is a perspective view of a tank according to an embodiment of the present invention, and FIG. 4 (A) 4 is a cross-sectional view of the window shown above, FIG. 4) is a diagram showing the state of the window seen from arrow A in FIG. FIG. 6 is a diagram showing an example of the display of the remaining liquid amount display section of the same as above. 11...Tank 12...Window 13...Sensor part 14...Light emitting diode 15...Phototransistor 18...Display lamp agent Masuo Oiwa (and 2 others) Figure 1 J Figure 3 Figure 2

Claims (1)

[Claims] a window extending from the top to the bottom of the liquid storage tank and whose reflectance changes depending on the close contact of the liquid; a means for emitting light from the top to the bottom of the window; and a means for emitting light from the window. A device for detecting the amount of remaining liquid in a tank, comprising: display means for detecting light from a plurality of places from the top to the bottom of the window and displaying the liquid level in the tank.