JPH056333U - Liquid level indicator - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a liquid level gauge having a simple structure and capable of continuously detecting a decrease in liquid level. A liquid level gauge in which at least one of a microphone and a speaker connected to an input side and an output side of an amplifier is fixed to one end of a cylindrical body and the other end of the cylindrical body is opened.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a liquid level gauge suitable for detecting the liquid level of a liquid storage tank, the liquid level of lubricating oil of a rotating body, and the like.

[0002]

[Prior Art]

 Conventionally, the detection of the liquid level of lubricating oil on a rotating body has been performed by inserting a long metal rod into the lubricating oil and then immediately pulling it out, and judging by the position of the lubricating oil adhering to the metal rod.

Since this method is simple, it has been widely adopted as a method for liquid level detection.

[0004]

[Problems to be solved by the device]

 However, when the decrease of the lubricating oil is rapid, this method requires frequent measurement and is complicated.

[0005]

[Means for Solving the Problems]

 Then, the present inventors have come to propose the present invention as a result of examining a liquid level gauge without the above-mentioned drawback.

That is, according to the present invention, at least one of the microphone and the speaker connected to the input side and the output side of the amplifier is fixed to one end of the cylinder, and the other end of the cylinder is opened. It is a liquid level gauge.

FIG. 1 is a schematic view showing a typical aspect of the present invention.

A microphone 2 and a speaker 3 are connected to the input side and the output side of the amplifier 1, respectively. The microphone 2 is fixed to one end of the tubular body 4, and the other end of the tubular body 4 is open. The cylindrical body 4 is fixed in the lubricating oil storage tank 5 of the rotating body bearing so that the one end to which the microphone 2 is fixed faces up and the other open end is located on the lowermost permissible surface of the lubricating oil. ing. On the other hand, the speaker 3 is fixed to the upper part of the lubricating oil storage tank of the rotating body bearing.

The output of the amplifier 1 is set so that the microphone 2 and the speaker 3 cause a howling phenomenon through an air layer. When the liquid level of the lubricating oil is above the other end of the opening of the cylindrical body 4, the sound wave emitted from the speaker 3 is attenuated by the lubricating oil and does not reach the microphone 2 so that the howling phenomenon does not occur. However, when the amount of lubricating oil decreases and the liquid level becomes lower than the other end of the opening of the cylindrical body 4, the sound wave from the speaker 3 reaches the microphone 2 through the air layer, which causes a howling phenomenon. If the howling phenomenon occurs, a howling sound is emitted and the decrease in the amount of lubricating oil can be detected. If the howling phenomenon occurs, the current on the input side and the output side of the amplifier rises. Therefore, by detecting the current, it is possible to detect the decrease in the amount of lubricating oil.

In FIG. 1, it is the microphone 2 that is fixed to one end of the tubular body, but the speaker 3 may be fixed, and as shown in FIG. 2, the microphone 2 and the speaker 3 are fixed. Both may be fixed to one end of the two tubular bodies 4 and 4 ', respectively. At this time, it is preferable to provide a cover 6 around the other ends of the cylindrical bodies 4 and 4'in order to prevent the sound wave of the microphone 2 from diffusing and to easily cause the howling phenomenon.

Further, as shown in FIG. 3, a U-shaped tube 7 is used as a tubular body, and the microphone 2 and the speaker 3 are fixed to both ends of the U-shaped tube 7 at the bent portion of the U-shaped tube 7. It is also possible to provide a hole 8 for letting in the liquid.

Further, as shown in FIG. 4, a liquid level gauge in which a double tube is used as a cylindrical body and a microphone 2 and a speaker 3 are fixed inside the end portions of the outer tube 9 and the inner tube 10 on the same side, respectively. Is also preferably used. At this time, in order to prevent the sound wave from the microphone 2 from being diffused, it is preferable that the outer tube is longer than the inner tube at the other ends of the outer tube 9 and the inner tube 10.

The liquid level gauge of the present invention can be applied not only to the liquid level detection of lubricating oil, but also to the liquid level detection of general liquids.

[0014]

[Effect of the device]

 The liquid level gauge of the present invention has a simple structure, and by using this, it is possible to continuously detect when the liquid level drops below the allowable limit of the liquid level. Further, since the liquid level gauge of the present invention can detect when the liquid level exceeds the upper limit, if two level gauges with different lengths are used, the allowable upper and lower limits of the liquid level can be determined. It is also possible to manage at the same time.

[0015]

【Example】

 Example The liquid level of the lubricating oil was detected using the liquid level gauge shown in FIG.

A microphone and a speaker are attached respectively to one end of an inner tube having an outer diameter of 7 mm and an outer tube having an outer diameter of 15 mm and a length of 10 mm longer than the open end of the inner tube to increase the output of the amplifier and howling. Caused the phenomenon. The output of the amplifier at this time was 0.5 W.

When this liquid level gauge was immersed in the lubricating oil in the storage tank so that the open end of the inner pipe was below the liquid level of the lubricating oil, howling stopped but the liquid level of the lubricating oil remained When the temperature was lower than the open end of the tube, a howling phenomenon occurred and a howling sound was produced.

[Brief description of drawings]

FIG. 1 is a schematic view showing a typical embodiment of a liquid level gauge of the present invention.

FIG. 2 is a schematic view showing another embodiment of the liquid level gauge of the present invention.

FIG. 3 is a schematic view showing another embodiment of the liquid level gauge of the present invention.

FIG. 4 is a schematic view showing another embodiment of the liquid level gauge of the present invention.

[Explanation of symbols]

 1 Amplifier 2 Microphone 3 Speakers 4 and 4'Cylinder 5 Lubricating Oil Storage Tank 6 Cover 7 U-shaped Tube 8 Hole 9 Outer Tube 10 Inner Tube

Claims (1)

[Claim 1] At least one of a microphone and a speaker connected to the input side and the output side of the amplifier is fixed to one end of the cylinder, and the other end of the cylinder is opened. Liquid level gauge.