JPH01193625A - Liquid specific gravity measurement and meter therefor - Google Patents

Abstract

PURPOSE:To enable continuous and easy measurement of a specific gravity of a liquid as desired with an inexpensive equipment, by arranging a photoconductor having a light transmitting surface at a part thereof to be dipped into the liquid with light incident into one end thereof. CONSTITUTION:A photoconductor 2 has a light transmitting surface at least at a part thereof which is dipped into a liquid and is, for example, given a shape of U. A light receiving section 3 receives light at the other end of a conductor 2 as coming from one end thereof after emitted by a light emitting section 1 and a light emitting section 5 receives light of the light emitting section 1 as reference light. In the process where light incident at one end of the conductor 2 is transmitted to the other end thereof, the refractive index of light on a contact surface between the conductor 2 and the liquid varies with the specific gravity of the liquid to change a transmission of light. Thus, this change is detected with a specific gravity conversion display section 9 thereby enabling continuous and very easy measurement of the specific gravity of the liquid as desired.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method and a liquid hydrometer for measuring the specific gravity of a liquid such as a storage battery electrolyte.

[Prior Art 1] Generally, the specific gravity of a storage battery electrolyte decreases upon discharging, and conversely increases upon charging. It is known that the degree of change in the specific gravity of the electrolyte is approximately proportional to the amount of electricity m flowing into the storage battery.

Conventionally, the most common method for measuring the specific gravity of an electrolyte is to collect the electrolyte of a storage battery in a container such as a test tube, float a float with a certain quality ω in the liquid, and then measure the float's rise and fall. A method was used to measure the specific gravity of the electrolytic solution by its amount.

[Problems to be Solved by the Invention] The electrolyte specific gravity measuring means as described above has a problem in that it is extremely cumbersome to operate and cannot perform continuous measurements or measurements while the vehicle is running on a storage battery mounted on the vehicle.

In response to this, it has recently been proposed to use an ultrasonic specific gravity sensor that utilizes the property that the propagation speed of ultrasonic waves in an electrolytic solution changes depending on the specific gravity of the solution, but this specific gravity sensor can be used for small storage batteries. The problem was that it was difficult to equip and was expensive.

An object of the present invention is to provide a liquid specific gravity measuring method and a liquid hydrometer that can extremely easily measure the specific gravity of not only electrolytes but also liquids at any time and continuously using inexpensive equipment.

[Means for Solving the Problems] In order to achieve the above object, the liquid specific gravity measuring method of the present invention uses a photoconductor 2 having at least a portion of a light-transmitting surface.
is arranged so that its light-transmitting surface is immersed in a liquid, and light is incident on one end of the photoconductor 2, and changes in photoconductivity m are detected from the light that has passed through the photoconductor 2. Then, the specific gravity of the liquid is obtained from the change in the amount of light conduction.

The liquid hydrometer of the present invention includes a photoconductor 2 in which at least a portion immersed in a liquid has a light-transmitting surface, and light is incident on the photoconductor 2 from one end of the photoconductor 2. a first light receiving section 3 that receives the light emitted from the photoconductor 2, and a second light receiving section that receives the light emitted from the light emitting section 1 as reference light. 5 and
A specific gravity conversion display section 9 is provided which detects a change in the optical flux 11 in the photoconductor 2 based on the light reception outputs of both the light receiving sections 3.5, converts it into the specific gravity of the liquid, and displays the result.

It is effective to form the photoconductor 2 into a U-shape or a coil shape.

Further, it is preferable that the light emitting section 1 is a light emitting diode, and the light receiving sections 3.5 are each a phototransistor.

Furthermore, it is preferable that the specific gravity conversion display section 9 has an amplifier 11 that differentially amplifies the light receiving outputs of both light receiving sections 3.5, and a display 13 that displays the specific gravity based on the output of the amplifier 11. ing.

[Function] In the liquid specific gravity measurement method described above, in the process in which light incident on one end of the photoconductor 2 is transmitted to the other end, the refractive index of the light at the contact interface between the photoconductor 2 and the liquid is equal to that of the liquid. By changing in accordance with the specific gravity, the amount of light transmitted by the photoconductor 2 changes in accordance with the specific gravity of the liquid. Therefore, by detecting this change in the amount of photoconductivity, the specific gravity of the liquid can be measured very easily at any time and continuously.

In the liquid hydrometer having the above-mentioned configuration, the photoconductor 2
The change in the amount of photoconductivity is detected based on the light reception output of both light receiving sections 3.5, and the detection result is converted into specific gravity and displayed by the specific gravity conversion display section 9. With this equipment, it can be easily measured and displayed with good accuracy anytime and continuously.

When the photoconductor 2 is formed into a U-shape or a coil shape, the photoconductor 2 can be easily inserted and immersed in a liquid in a small container, and the photoconductor 2 contributes to specific gravity detection. A sufficient contact interface between the liquid and the liquid can be obtained.

A light emitting diode is used for the light emitting section 1, and a light receiving section 3.
When a phototransistor is used as the photoconductor 5, the necessary light is incident on the photoconductor 2 and the light emitted from the photoconductor 2 is properly received.

Also, ratio a! ! i! The ti display section 9 displays the specific gravity based on the output obtained by differentially amplifying the light reception outputs of both the light receiving sections 3 and 5, so that the light emission amount may fluctuate to some extent due to temperature changes or deterioration of the light emitting section 1. However, it is possible to perform highly accurate specific gravity conversion display that is not affected by this.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
The figure shows the configuration of the sensor section of the hydrometer of this embodiment, which is immersed in a storage battery electrolyte.

In the figure, reference numeral 6 denotes a mounting member similar to a liquid spout plug, etc., to the storage battery container lid plate, and 2 indicates a photoconductor with a light-transmitting surface made of an optical fiber supported by this mounting member and provided in a U-shape. ,
Reference numeral 4 denotes a photoconductor made of an optical fiber arranged with one end side close to one end side of the photoconductor 2, and 1 a light emitting section made of a light emitting diode arranged opposite to each other at one end side of the photoconductor 2.4. , 3 is a first light-receiving section consisting of a phototransistor disposed on the other end side of the photoconductor 2, and 5 is a second light receiving section consisting of a phototransistor disposed on the other end side of the photoconductor 4. This is the light receiving section.

The sensor section configured as described above is constructed by fitting the mounting member 6 into a mounting portion previously provided on the lid plate of the storage battery container, and attaching the U-shaped photoconductor 2 that protrudes downward from the mounting member 6 to the battery container. and immerse it in the electrolyte.

Figure 2 shows the driving circuit of the light emitting part 1, and Figure 3 shows the detection of slight changes in light transduction in the photoconductor 2 based on the amount of light received by both light receiving parts 3.5 and converting it into the specific gravity of the electrolyte. This figure shows the configuration of the specific gravity conversion display section 9 that displays the specific gravity. As shown in FIG. 2, the light emitting diode 1 constituting the light emitting unit 1 is stably driven from a constant voltage circuit 7 connected to a power source via a constant current circuit 8, so that it emits a constant amount of light 8. It has become.

In the specific gravity conversion display section 9 shown in FIG. of the operational amplifier 11 via R4 (
-) input terminal, and the output of the phototransistor 5 is inputted to the (+) input terminal of the operational amplifier 11 via a resistor R9. A DC operating voltage is provided.

The operational amplifier 11 outputs a differentially amplified output for both human power, and upon receiving this output, the display drive circuit 12 outputs an output whose polarity is inverted, and the display drive circuit 12 outputs an output with the polarity inverted.
The specific gravity value is displayed in 3.

In the hydrometer having the above configuration, light emitted from the light emitting section 1 is transmitted through the photoconductor 2, and light emitted from the other end of the photoconductor 2 is received by the light receiving section 3. During this photoconduction, the refractive index of light changes depending on the specific gravity of the electrolyte at the contact interface between the photoconductor 2 and the electrolyte, so that the specific gravity of the electrolyte is transferred from the photoconductor 2 to the electrolyte. some a according to
light leaks out. That is, the light conduction m in the photoconductor 2 is attenuated according to the specific gravity of the electrolytic solution, and the greater the specific gravity, the greater the amount of attenuation. Therefore, the light received by the light receiving section 3 changes depending on the specific gravity of the electrolytic solution. Now, if the amount of light emitted from the light emitting section 1 is 01, and the amount of light received by the light receiving section 3 is Q2, the relationship Ql - ηQ2 is established between the two. Here, η is the combination of the specific gravity value and the proportionality constant. On the other hand, the light emitted from the light emitting section 1 and transmitted through the photoconductor 4 is received by the light receiving section 5 without being attenuated. That is, if this amount of received light is 03, then Q1=Q3. As explained in FIG. 3, the specific gravity conversion display section 9 differentially amplifies the light receiving outputs of both light receiving sections 3.5 and converts it into specific gravity and displays it. Even if the light emission ff1Q+ of the light emitting section 1 changes to some extent due to change or deterioration, and the light receiving output of the light receiving section 3 is affected by this, the light receiving output of the light receiving section 5 is also affected in the same way. The detection output is corrected without being affected by the above, and the accurate specific gravity value is displayed on the display 13. In this embodiment, a DC voltmeter is used as the display 13, and the specific gravity of the electrolyte is 1. For OO~1.40,
A DC output voltage of 2.0 to 50V was obtained from the display drive circuit 12. Accordingly, by setting the scale of the DC voltmeter used in the display 13 as a specific gravity value scale, the specific gravity of the electrolytic solution can be directly read.

In addition, although the above-mentioned Example described the case of measuring the specific gravity of a storage battery electrolyte, the present invention is not limited to this and can be similarly applied to measuring the specific gravity of a general liquid.

Further, in the above embodiment, the photoconductor 2 immersed in the electrolytic solution was formed into a U-shape, but the shape may be formed into a coil shape, and if it is formed into a coil shape, the specific gravity can be detected. Viscosity is further improved.

Furthermore, in the above embodiment, the light receiving section 5 receives the light from the light emitting section 1 via the photoconductor 4, but the light receiving section 5
may be arranged near the light emitting section 1 without receiving light from other sources, so that the light from the light receiving section 1 is directly received.

Alternatively, the light from the light receiving section 1 may be divided into two by a half mirror into transmitted light and reflected light, one light, for example, the transmitted light, may be made to enter the photoconductor 2, and the other reflected light may be directly received by the light receiving section 5. You may also do so.

[Effects of the Invention] Since the present invention is configured as described above, it has the following effects.

The change in photoconductivity Q in a photoconductor with a light-transmitting surface immersed in a liquid is detected, and the specific gravity of the liquid is obtained from the change in the photoconductivity aperture, so that it can be carried out very easily at any time and continuously. The specific gravity of a liquid can be measured.

The liquid hydrometer of the present invention uses light receiving output based on the light receiving outputs of both the light receiving part, which receives the light emitted from the photoconductor and the light receiving part which receives the light from the light emitting part as reference light. It detects the change in light transduction in the conductor, converts it to the specific gravity of the liquid, and displays it, making it easy to measure the specific gravity of the liquid at any time, continuously, and with good accuracy using relatively inexpensive equipment. The measurements can be displayed.

By forming the above-mentioned photoconductor into a zero-shape or a coil shape, the photoconductor can be easily inserted and immersed into a liquid in a small container, and also contributes to specific gravity detection. A sufficient contact interface between the photoconductor and the liquid can be obtained.

In addition, the light emitting part is a light emitting diode, and the light receiving part is a photodiode.
By using a transistor, necessary light can be incident on the photoconductor and light emitted from the photoconductor can be properly received.

Furthermore, the specific gravity conversion display section displays the specific gravity based on the output of an amplifier that differentially amplifies the light receiving outputs of the two light receiving sections, so that the amount of light emitted may fluctuate to some extent due to temperature changes or deterioration of the light emitting section. It is possible to measure the specific gravity of a roaring liquid with high accuracy without being affected by it.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the configuration of the sensor unit according to the embodiment of the present invention, FIG. 2 is a circuit diagram showing the configuration of the light emitting unit driving circuit of the embodiment, and FIG. 3 is a specific gravity conversion display unit of the embodiment. FIG. DESCRIPTION OF SYMBOLS 1... Light emitting part consisting of a light emitting diode, 2... Photoconductor consisting of an optical fiber, 3... First light receiving part consisting of a phototransistor, 5... Second light receiving part consisting of a phototransistor. Light receiving section, 9...Specific gravity conversion display section, 1
1... operational amplifier, 13... indicator. @1 Figure

Claims (5)

[Claims] (1) Photoconductor 2 having a light-transmitting surface at least in part
is arranged so that its light-transmitting surface is immersed in a liquid, and light is incident on one end of the photoconductor 2, and changes in the amount of light conduction are detected from the light that has passed through the photoconductor 2. and a liquid specific gravity measuring method for obtaining the specific gravity of the liquid from the change in the amount of photoconductivity. (2) a photoconductor 2 whose at least a portion immersed in a liquid has a light-transmissive surface; a light emitting section 1 that allows light to enter the photoconductor 2 from one end of the photoconductor 2; a first light receiving section 3 that receives light emitted from the other end of the photoconductor 2; a second light receiving section 5 that receives light emitted from the light emitting section 1 as reference light; and both light receiving sections 3. . (3) The liquid hydrometer according to claim (2), wherein the photoconductor 2 immersed in the liquid has a U-shape or a coil shape. (4) The liquid hydrometer according to claim (2), wherein the light emitting section 1 is a light emitting diode, and the light receiving sections 3 and 5 are each phototransistors. (5) The specific gravity conversion display section 9 includes an amplifier 11 that differentially amplifies the light receiving outputs of both the light receiving sections 3 and 5, and a display 13 that displays the specific gravity based on the output of the amplifier 11.
) liquid hydrometer as described in ).