Liquid position sensor

Abstract

To provide a liquid position sensor which detects an amount of liquid while suppressing reduction of capacity of a container and electric corrosion thereof.SOLUTION: A liquid position sensor 10 detects an amount of liquid 13, and comprises: a container 12 for storing the liquid 13; a plurality of thin-film solar cells 15 which are disposed at different height positions in the container 12 and of which surfaces are covered with light-transmissive protection parts 16; a light source 18 which emits light L toward the plurality of thin-film solar cells 15 from above the liquid surface 13a of the liquid 13 in the container 12; a storage part 21 for storing the height positions of the thin-film solar cells 15; and a determination part 22 for determining a position of the liquid surface 13a of the liquid 13 on the basis of a power generation amount of the thin-film solar cells 15 at the height positions that are stored by the storage part 21.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed in this specification relates to a liquid position sensor, and more particularly to a liquid position sensor that detects the amount of liquid. [Background technology]

[0002] Conventionally, there is a liquid level sensor that includes an insulating substrate on which a pair of electrodes is arranged, and detects the amount of liquid in a storage tank (container) based on a change in electrostatic capacitance between the pair of electrodes (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-118894 Summary of the Invention [Problem to be solved by the invention]

[0004] In the conventional liquid level sensor, the insulating substrate, which is a plate-like member, has a large volume, and therefore when placed in a container, the volume of the container is reduced. In addition, the pair of electrodes is exposed to the liquid, which causes electrical corrosion of the pair of electrodes.

[0005] The problem to be solved by the technique disclosed in this specification is to detect the amount of liquid while suppressing the reduction in volume of the container and electrical corrosion. [Means for solving the problem]

[0006] In order to solve the above problems, the technique disclosed in this specification takes the following measures.

[0007] The technology disclosed in this specification is a liquid position sensor that detects the amount of liquid, and includes a container for storing the liquid, a plurality of thin-film solar cells that are arranged at different height positions within the container and are covered with a protective portion whose surface is optically transparent, a light source that irradiates light toward the plurality of thin-film solar cells from above the liquid surface within the container, a memory unit that stores the height position of each of the thin-film solar cells, and a judgment unit that judges the position of the liquid surface based on the amount of power generated by the thin-film solar cells at each height position stored in the memory unit.

[0008] According to this configuration, the amount of power generated by each thin-film solar cell increases or decreases depending on whether or not the light irradiated from the light source passes through the liquid in the container. Then, the judgment unit judges the position of the liquid level based on the amount of power generated by the thin-film solar cell at each height position stored in the memory unit. This makes it possible to detect the amount of liquid using the thin-film solar cell. Furthermore, since the thin-film solar cell is thinner and has a smaller volume than a conventional plate-shaped insulating substrate, it is possible to suppress a decrease in the capacity of the container. Furthermore, since the surface of the thin-film solar cell is covered with a protective part having optical transparency, it is possible to suppress electrical corrosion while suppressing a decrease in the power generation efficiency of the thin-film solar cell. Therefore, it is possible to suppress a decrease in the capacity of the container and electrical corrosion while detecting the amount of liquid.

[0009] In addition, the liquid position sensor supplies the light source with power generated by the thin-film solar cell, thereby eliminating the need for a dedicated power source for the light source. Effect of the Invention

[0010] According to the technology disclosed in this specification, it is possible to detect the amount of liquid while suppressing the reduction in volume of the container and electrical corrosion. [Brief description of the drawings]

[0011] [Figure 1] FIG. 1 is a cross-sectional view of a liquid position sensor according to one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] An embodiment for carrying out the technology disclosed in this specification will be described below with reference to the drawings. Fig. 1 is a cross-sectional view showing a liquid position sensor. As shown in Fig. 1, the liquid position sensor 10 includes a box-shaped container 12 that is open at the top. Liquid 13 is stored in the container 12.

[0013] On the inner wall surface of one wall portion 12a of the container 12 (the left side in FIG. 1), a plurality of thin-film solar cells 15 are arranged at different height positions. In FIG. 1, a total of three thin-film solar cells 15 are arranged on the upper, middle and lower tiers. As the thin-film solar cells 15, for example, perovskite solar cells are preferable. Perovskite solar cells are thin, light and highly flexible, and can be manufactured inexpensively by coating, printing or the like. The surface of each thin-film solar cell 15 is covered with a protective film 16 having optical transparency.

[0014] A directional light source 18 is disposed via a bracket (not shown) above the other (right side in FIG. 1) wall portion 12b of the container 12. In FIG. 1, two light sources 18 are disposed, one above the other. The light source 18 is, for example, a lighting device equipped with a light emitting element 18a such as an incandescent bulb or an LED. The light source 18 is equipped with a reflector 19. The power source for both light sources 18 is a thin-film solar cell 15. That is, the power generated by the thin-film solar cell 15 is supplied to both light sources 18.

[0015] Both light sources 18 are arranged to irradiate light L toward the three thin-film solar cells 15 from above the liquid surface 13a of the liquid 13 in the container 12. For example, the lower light source 18 is arranged to irradiate light L toward the thin-film solar cell 15 in the lower row, and the upper light source 18 is arranged to irradiate light L toward both the thin-film solar cells 15 in the upper row and the middle row.

[0016] A memory unit 21 and a determination unit 22 are provided on the outer wall surface of one wall portion 12a of the container 12. The memory unit 21 stores the arrangement positions of each thin-film solar cell 15 and transmits them as ID (identification information) to the determination unit 22. The determination unit 22 determines the position of the liquid level 13a of the liquid 13 in the container 12 based on the amount of power generated by each thin-film solar cell 15 associated with the ID stored in the memory unit 21, i.e., the thin-film solar cell 15 at each height position.

[0017] (Actions and Effects of the Embodiments) According to this embodiment, the amount of power generated by each thin-film solar cell 15 increases or decreases depending on whether or not the light L irradiated from each light source 18 passes through the liquid 13 in the container 12. That is, if the light passes through the liquid 13, the amount of power generated by the thin-film solar cell 15 that receives the light L decreases. On the other hand, if the light does not pass through the liquid 13, the amount of power generated by the thin-film solar cell 15 that receives the light L increases.

[0018] Then, the judgment unit 22 judges the position of the liquid surface 13a of the liquid 13 based on the amount of power generated by the thin-film solar cell 15 at each height position stored in the memory unit 21. This allows the amount of liquid 13 to be detected using the thin-film solar cell 15. Furthermore, since the thin-film solar cell 15 is thinner and has a smaller volume than a conventional plate-shaped insulating substrate, it is possible to suppress a decrease in the capacity of the container 12. Furthermore, since the surface of the thin-film solar cell 15 is covered with the protective part 16 having optical transparency, it is possible to suppress electrical corrosion while suppressing a decrease in the power generation efficiency of the thin-film solar cell 15. Therefore, it is possible to suppress a decrease in the capacity and electrical corrosion of the container 12 while detecting the amount of liquid 13.

[0019] Moreover, the power generated by the thin-film solar cell 15 is supplied to both light sources 18. This makes it unnecessary to provide a dedicated power source for both light sources 18.

[0020] [Other embodiments] The technology disclosed in this specification is not limited to the above-described embodiment, and can be embodied in various other forms. For example, the number of thin-film solar cells 15 may be increased or decreased. Also, the number of light sources 18 may be increased or decreased. [Explanation of symbols]

[0021] 10 Liquid Position Sensor 12 containers 13 liquid 13a Liquid level 15 Thin film solar cells 16 Protection Department 18 light source 21 Memory section 22 Judgment Department L light

Claims

1. A liquid position sensor for detecting a liquid amount, comprising: A container for storing the liquid; A plurality of thin-film solar cells are arranged at different heights within the container and have surfaces covered with protective portions having optical transparency; a light source that irradiates light from above the liquid level in the container toward the thin-film solar cells; A storage unit that stores a height position of each of the thin-film solar cells; a determination unit that determines a position of a liquid surface of the liquid based on the amount of power generated by the thin-film solar cell at each height position stored in the memory unit; 1. A liquid position sensor comprising:

2. 2. The liquid position sensor of claim 1, The liquid position sensor supplies the light source with power generated by the thin-film solar cell.

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