JPH0368848A - Alcohol concentration detector - Google Patents

Abstract

PURPOSE:To improve the measuring accuracy of alcohol concentration by detecting the flow rate of a gas flowing through a gas sucking pipe, and controlling the amount of gas flowing through a gas feeding pipe in response to the deviation between the detected flow rate and a reference value. CONSTITUTION:An upper end 211 of a tubular member 21 is closed with an upper end closing member 20. A lower end 212 is an opening end. A gas feeding pipe 22 has a gas sending means 24. The lower end of the gas feeding pipe 22 is made to penetrate through the upper end closing member 20 and suspended in the tubular member 21. A lower end 221 is terminated at a part higher than the lower end 212 of the tubular member 21. A gas-temperature detecting means 27 is provided in a gas sucking pipe 26. A gas-flow-rate detecting means 261 detects the flow rate of the gas flowing through the gas sucking pipe 26. A flow-rate control means 31 controls the flow rate of the gas flowing through the gas feeding pipe 22 in response to the deviation between the detected flow rate and a reference value 34. Thus, the air at the constant flow rate is sent into the gas sucking pipe 26, and the measuring accuracy of the concentration of alcohol obtained from the gas temperature with a temperature detecting means 27 can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an improvement in an alcohol concentration detection device.In particular, the present invention relates to an improvement in an alcohol concentration detection device. It relates to an improvement in an alcohol concentration detection device that detects the concentration of alcohol contained in it.More specifically, it is capable of continuous measurement, and
Even if impurities are mixed in the alcohol-containing liquid to be tested, continuous measurement is possible for a long period of time, and it can be used regardless of the depth of the alcohol-containing liquid to be tested, and has high measurement accuracy. This invention relates to an improvement of an alcohol concentration detection device with the purpose of achieving extremely good alcohol concentration detection.

[Conventional technology]

2. Description of the Related Art It has been necessary to detect the concentration of alcohol contained in alcohol-containing liquids such as alcoholic beverages and so-called dampening water used in lithographic printing.

As an example of a conventional alcohol concentration detection method,
In addition to the method of using a hydrometer, etc., in each case, the test liquid containing alcohol is pumped out, the specific gravity of the test alcohol-containing aqueous solution is measured, and the specific gravity is calculated based on this specific gravity. Methods for detecting alcohol concentration are known.

However, since the above-mentioned detection method is a discontinuous measurement method, it is difficult to avoid the drawback that it is necessary to pump out the test liquid containing alcohol each time detection is performed.

Therefore, the semi-continuous measurement means shown in Fig. 3 (each time detection
No need to pump out test liquid containing alcohol;
) has now been provided.

In the drawing shown in FIG. 3, 1 is a test liquid containing alcohol, 2 is an opening provided on its lower surface facing the natural liquid level of the above test liquid l, and its side wall is immersed in the test liquid. immersed in
It is a box-shaped body in which a space remains between the natural liquid level of the test liquid I, and 3 penetrates the side surface of this box-shaped body, and the box-shaped body 2 and the above test liquid It is a blowing pipe that sends air into the space remaining between the natural liquid level of the liquid 1, and 4 passes through the other side of this box-like body 2. 6 is an exhaust pipe that exhausts air to the outside from the space remaining between the natural liquid surface of the test liquid 1, and 6 is an exhaust pipe that exhausts air to the outside from the space remaining between This is a gas sensor attached to the box-shaped body 2 for the purpose of measuring the concentration of alcohol in the container.

When detecting the concentration of alcohol contained in the test liquid 1 using this alcohol concentration measuring means, air is introduced through the blower pipe 3 and then the air inside the box-shaped body 2 is discharged from the visible exhaust vibrator 4. The alcohol vapor in the space remaining between the box body 2 and the natural liquid level of the test liquid 1 is removed, and the alcohol vapor in the space remaining between the box body 2 and the natural liquid level of the test liquid 1 is removed. After purging the space remaining between the two, and leaving it for a certain period of time to sufficiently evaporate the alcohol contained in the test liquid l, the alcohol concentration in the gas filling the space is determined. is measured using a gas sensor 6, and the concentration of alcohol contained in the test liquid 1 is detected based on the result.

Therefore, even when measuring alcohol concentration using this measuring means, completely continuous measurement was not possible.

At the same time, the saturated vapor pressure of alcohol is
It is clear that the fi degree of alcohol in the gas containing evaporated alcohol does not necessarily accurately represent the concentration of alcohol contained in the liquid 1 to be tested.

Therefore, by continuously measuring the concentration of alcohol that evaporates from the alcohol-containing test liquid using a gas sensor, and also measuring the temperature of the alcohol-containing test liquid, and adding temperature correction, it is possible to A means has now been provided for measuring the alcohol concentration of a test liquid. This measuring means is shown in FIG.

In the diagram shown in FIG. 4, 1 is a test liquid containing alcohol;
3 is a ventilation pipe, one end of which is connected to a ventilation pump 9, and the other end immersed in the liquid to be tested 1. Reference numeral 4 denotes an exhaust pipe, one end of which is immersed in the liquid to be tested 1, and the other end is open to the atmosphere. 6 is a gas sensor;
It is provided in the middle of the exhaust pipe 4 described above. 7 is a porous polymer whose both ends are connected to the end of the blower pipe 3 immersed in the test liquid I and the end of the exhaust pipe 4 immersed in the test liquid 1. This is a gas sampling tube formed by a gas-liquid separation membrane made of a membrane or the like. A temperature sensor 8 is immersed in the test liquid 1 to measure the temperature of the test liquid 1.

When using this measuring device to detect the alcohol concentration of the test liquid 1, the ventilation pump 9 is used to send air into the ventilation pipe and release it into the atmosphere through the gas sampling pipe, exhaust pipe, and gas sensor. Then, the inside of the gas sampling tube 7 is purged. The alcohol contained in the test liquid 1 becomes vapor and enters the gas sampling tube through a gas-liquid separation membrane made of a porous polymer membrane or the like that constitutes the gas sampling tube 7.
It is guided to the gas sensor 6 together with the blown air. The alcohol concentration is measured by the gas sensor 6, the measured alcohol concentration is temperature-corrected based on the temperature of the test liquid 1 measured by the temperature sensor 8, and the alcohol concentration contained in the test liquid 1 is corrected based on the result. It measures alcohol concentration.

[Problem to be solved by the invention]

However, the alcohol concentration measuring means shown in Figure 4 above is not suitable for measuring the concentration of an alcohol aqueous solution that does not contain many impurities, such as a fully charged alcoholic beverage (alcoholic beverage that is not being brewed). However, it is suitable for test liquids such as alcoholic beverages being brewed, and alcohol aqueous solutions that contain insoluble matter such as ink scum, such as bleaching water used in lithographic printing. ,
This insoluble matter covers the gas-liquid separation membrane and prevents the alcohol from passing through the gas-liquid separation membrane and becoming vaporized, resulting in an error in the measurement results.

According to the results of experiments, after about 40 days of use, the measured value decreased by about 10% even at the same alcohol concentration.

The purpose of the present invention is to eliminate the various drawbacks that have been unavoidable in the above-mentioned various alcohol concentration detection devices, and (a) continuous measurement is possible even if the sample liquid is contaminated with impurities; (b) It can be used regardless of the depth of the liquid to be tested; (c) it is also corrected for changes in the temperature of the liquid to be tested; (d) it is also corrected for changes in the ambient air temperature; An object of the present invention is to provide an alcohol concentration detection device that is improved to have sufficiently high accuracy.

[Means to solve the problem]

The above object can be achieved by any of the following means.

The first means is a cylindrical member (2) whose upper end (211) is closed with an upper end closing member (20) and whose lower end (212) is an open end.
1), passing through the upper end closing member (20) and hanging down into the cylindrical member (21), the lower end (221) of which is lower than the lower end (212) of the cylindrical member (21). A gas supply pipe (22) that terminates at the upper part and has an air supply means (24), the lower end of which is immersed in the test liquid, and is provided to pass through the upper closing member (20). Gas suction pipe (26)
and a gas temperature detection means (27) provided in the gas suction pipe (26) to detect the temperature of the gas, and based on the temperature detected by the gas temperature detection means (27), the temperature of the gas is determined. Gas temperature change detection means (28
), a temperature change/alcohol concentration correction means (29) for correcting the temperature change of the gas to the test alcohol concentration, and an alcohol concentration output means (30) for outputting information representing the corrected alcohol concentration. In the alcohol concentration detection device, the gas flow rate detection means (261) detects the gas flow rate flowing through the gas suction pipe (26);
An alcohol concentration detection device comprising a flow rate control means (31) for controlling the amount of gas flowing through the gas supply pipe (22) in response to a deviation between the flow rate of the gas flow rate detection means (261) and a reference value. Yes (corresponding to claim 1).

The second means includes a cylindrical member (2) whose upper end (211) is closed with an upper end closing member (20) and whose lower end (212) is an open end.
1), which passes through the upper end closing member (20) and hangs down into the cylindrical member (21), and whose lower end (221) is above the lower end (212) of the cylindrical member (21). a gas supply pipe (22) having an air supply means (24) and whose lower end is immersed in the test liquid; and a gas supply pipe (22) which is provided through the upper closing member (20). a suction pipe (26); a gas temperature detection means (27) provided in the gas suction pipe (26) for detecting the temperature of the gas; Cylindrical member (21)
Test liquid temperature detection means (3) for detecting the temperature of the liquid containing test alcohol provided near the lower end (221) of
2); gas temperature change detection means (33) for detecting a temperature change in the gas by comparing the temperature of the test liquid with the gas salt; In an alcohol concentration detection device having a temperature change/alcohol concentration correction means (29) that outputs information representing the corrected alcohol concentration, and an alcohol concentration output means (3o) that outputs information representing the corrected alcohol concentration, the gas suction pipe (26) is gas flow rate detection means (261) for detecting the undulating gas flow rate;
An alcohol concentration detection device comprising a flow rate control means (31) for controlling the amount of gas flowing through the gas supply pipe (22) in response to a deviation between the flow rate of the gas flow rate detection means (261) and a reference value. Yes (corresponding to claim 2).

[Effect]

The alcohol concentration detection device according to the present invention includes a gas supply pipe 2
2, regardless of the liquid depth of the test liquid, an appropriate amount of air is blown into the test liquid 10 to evaporate an amount of alcohol vapor proportional to the concentration of alcohol contained in the test liquid 10. Then, an amount of alcohol vapor proportional to the concentration of alcohol contained in the test liquid 10 is pumped through the gas suction pipe 26.
The alcohol vapor thus sucked out is oxidized with the oxygen in the air supplied at the same time, and the amount of heat generated during this chemical reaction is used as the gas temperature detection means 27.
For example, a temperature sensing resistor is heated, and the change in the resistance value of the gas temperature detecting means 27 is electrically measured based on the temperature change of the resistor etc. gas temperature detecting means 27 due to this heating. This device detects the concentration of alcohol contained in alcohol.

In the alcohol concentration detection device according to the present invention, a fixed amount of air is delivered into the liquid to be tested 10 via the gas supply pipe 22 per unit time. The air sent into the test liquid 10 becomes bubbles, rises in the test liquid 10, and is discharged from the liquid surface into the atmospheric space within the cylindrical member 21. At this time, since the amount of air supplied is uniform per unit time, the above-mentioned bubbles, that is, the gas sucked out from the gas suction pipe 26, are
It always contains an amount of alcohol that is representative of the concentration of alcohol contained in the test liquid 10. Therefore, the amount of heat generated per unit time when the gas containing alcohol vapor is oxidized by oxygen in the supplied air represents the concentration of alcohol contained in the liquid 10 to be tested. This generated heat heats the gas temperature detection means, such as a temperature sensing resistor 27, and this generated heat is
The temperature of the gas temperature detecting means 27, such as a temperature sensing resistor, is
The alcohol concentration is increased approximately in proportion to the alcohol concentration, and the amount of heat generated changes the resistance value of the gas temperature detecting means 27, such as a temperature sensing resistor, in response to the temperature rise. This change in resistance value is electrically measured using gas temperature change detection means 28. At this time, the temperature of the surrounding air and the temperature of the liquid to be tested 10 are also measured, and the temperature is adjusted to eliminate the measurement value error that is caused to the output of the gas temperature detection means due to these temperature changes. It is effective to perform correction to improve accuracy.

As mentioned above, the important point in the alcohol concentration detection device according to the present invention is that the sample liquid is supplied through the gas supply pipe 22! The aim is to maintain a constant flow rate of air that is sent out during Q, rises in the test liquid 10 as bubbles, and is released from the liquid surface into the atmospheric space within the cylindrical member 21. However, when the alcohol concentration detection device is fixed and the air supply means outputs a constant pressure, when the liquid depth changes and the depth from the liquid level to the lower end 221 of the gas supply pipe 22 changes, , it becomes impossible to send a constant flow rate of air through the gas supply pipe 224, resulting in measurement errors. FIG. 2 shows the variation in the measured value of the alcohol concentration when the immersion depth of the alcohol concentration detection device changes.

In the diagram shown in FIG. 2, three curves show fluctuations in the measured value of the concentration when the immersion depth of the alcohol concentration detection device changes, and are shown using the concentration as a parameter. Both curves have the disadvantage that when the degree of immersion increases and exceeds a certain value, the measured value tends to drop rapidly, in other words, the measurement error tends to increase rapidly.

This drawback is difficult to overlook, especially when unexpected changes in the immersion depth of the alcohol concentration detection device are unavoidable, such as when detecting the alcohol concentration of so-called dampening water used in lithographic printing. be.

In order to avoid such an increase in measurement error, the alcohol concentration detection device according to the present invention includes a gas suction pipe 2.
Gas flow rate detection means 261 for detecting the gas flow rate flowing into 6
A flow rate control means 31 is provided which compares the gas flow rate detected by the gas flow rate detection means 261 with a reference value 32 and controls the gas flow rate flowing into the gas supply pipe 22 in response to a deviation between the two. It is. This flow rate control means 31
Therefore, even if the liquid depth changes while the alcohol concentration detection device is stably supported, it is possible to send a constant stream of air to the gas suction pipe 26 by adjusting the output pressure of the air supply means 24 to 11 points. Therefore, the particle size for measuring the alcohol concentration of a liquid to be tested containing alcohol can be significantly improved.

〔Example〕

Hereinafter, alcohol concentration detection devices according to two embodiments of the present invention will be described with reference to the drawings.

In the drawing shown in FIG. 1a, 20 is an upper end closing member that supports a cylindrical member 21, a gas supply pipe 22, and a gas suction pipe 26.

The upper end 211 of the cylindrical member 21 is closed by the upper end closing member 20, and the lower end 212 thereof is an open end and is immersed in the test liquid 10 containing alcohol. Further, the lower end 221 of the gas supply pipe 22 is connected to the above-mentioned cylindrical member 21.
It ends above the lower end 212 of.

Since the gas supply pipe 22 is provided with an air supply means 24, air or the like is supplied into the test liquid 10 containing alcohol inside the cylindrical member 21.

By the way, since the lower end 221 of the gas supply pipe 22 ends above the lower end 212 of the above-mentioned cylindrical member 21, the supplied air, etc. is prevented from leaking to the outside of the cylindrical member 21, and air bubbles and the like are prevented. At this time, the sample liquid 10 containing alcohol is vaporized, and a gas having an alcohol gas concentration representative of the alcohol concentration of the sample liquid 10 containing alcohol is transferred to the cylindrical member 21. 2I
supply to the space above. The gas supplied to the space above the cylindrical member 21 is sucked out through the gas suction pipe 26, reacts with oxygen in the air within the gas suction pipe 26, and generates heat.

A resistor 27 serves as a gas temperature detection means provided in the gas suction pipe 26, and is heated by heat generated when alcohol vapor is oxidized, so that its resistance value changes. The resistance value of this resistor is measured by a resistance measuring device (11!) such as a Wheatstone bridge having the above-mentioned gas temperature detection means 27 on one side.

By the way, since the alcohol concentration of the test liquid 10 containing alcohol depends on the temperature rise of the above-mentioned resistor, that is, the change in resistance value (change in temperature), changes) need to be measured.

However, since heat is generated and heat is dissipated at the same time, the resistance value of the above-mentioned resistor depends on the temperature of the surrounding air, and also depends on the temperature of the test liquid 10 containing alcohol and the temperature of the surrounding air. The difference also depends on the relative temperature of the surrounding air, etc., so in order to find the temperature rise of the above resistor, that is, the change in resistance value (change in temperature) from the resistance value of the above resistor, what is necessary? This revision is necessary. The functional element that performs this correction is the gas temperature change detection means 28, and this gas temperature change detection means uses the resistance value of the resistor as well as the various parameters described above as original information to determine the resistance of the resistor. The value is converted into a temperature rise of the resistor, that is, a change in temperature, and this is output. This function can be easily implemented using a table lookup method using a table created based on the results of experiments performed using the various parameters described above.

In response to this output, temperature change/alcohol concentration correction means 29 outputs alcohol concentration based on the input temperature change value, and alcohol concentration output means 30 in the next stage outputs alcohol concentration according to a desired output method. . This function can also be easily realized by using a table lookup method using a table created based on the results of experiments using the various parameters described above.

31 is a flow rate control means according to the gist of the present invention, and the gas flow rate detected by the gas temperature detection means 261 provided in the middle of the gas suction pipe 26 and a reference value 34 are input to this flow rate control means 31. In response to the deviation between the two, the output pressure of the air supply means 24 is set to tJ4, and the above gas suction pipe 26 is
The flow rate of gas flowing through the system is controlled to a constant reference value. Reference numeral 35 denotes support means for the alcohol concentration detection device, which stably supports the alcohol concentration detection device, for example, in a tank 36 containing the test liquid 10 containing alcohol.

In the alcohol concentration detection device according to the present invention, a fixed amount of air is sent into the test liquid 10 via the gas supply pipe 22 per unit time, regardless of the depth of the test liquid 10. The air sent into the test liquid 10 becomes bubbles, rises in the test liquid IO, and is discharged from the liquid surface into the atmospheric space within the cylindrical member 21. At this time, since the amount of air supplied is constant per unit time, the above-mentioned air bubbles are generated in the sample liquid 10 regardless of the depth of the sample liquid 10.
containing an amount of alcohol vapor representative of the concentration of alcohol contained therein. Therefore, the amount of heat generated per unit time when this alcohol vapor is oxidized by oxygen in the supplied air is the amount of heat generated per unit time of the alcohol contained in the sample 10, regardless of the depth of the sample liquid. It will represent the concentration. The amount of heat generated is the temperature sensing resistor 2.
7 is heated, the temperature of this temperature-sensitive resistor 27 rises in proportion to the above alcohol concentration, and the resistance value changes corresponding to the temperature rise. This change in resistance value is electrically measured. This temperature rise value is input to the temperature change/alcohol concentration correction means 29, and the sample is tested based on a list of alcohol concentrations using parameters such as the type of liquid to be tested and the humidity in the air. The alcohol concentration of the liquid is detected, and the alcohol concentration output means 30 outputs the alcohol concentration according to a desired output method.

31 is a flow rate control means according to the gist of the present invention, and the gas flow rate detected by the gas flow rate detection means 261 and the reference 4
Based on the deviation from 1134, the output pressure of the air supply means 24 is adjusted to 11 points, and the gas flow rate flowing into the suction pipe 26 is controlled to a constant reference value. As a result, test liquid 10 containing alcohol
Regardless of the liquid depth, the measurement accuracy of the alcohol concentration of the test liquid can be significantly improved. Further, the above-mentioned alcohol concentration detection device is stably supported by the support means 35 in the test liquid tank 36 or the like.

The difference with the first example is that in the first example, the air temperature is used as the reference value for correction, whereas in the second example, the temperature of the liquid in the subject IO is used as the reference value for correction. That's true.

In the figure, reference numeral 32 denotes a test liquid temperature detection means, which has a test liquid temperature sensor 321 at its lower end. Other operations are generally the same as in the first example.

〔Effect of the invention〕

As explained above, the alcohol concentration detection device according to the present invention uses an air supply means to send gas such as air through a gas supply pipe into a subject as bubbles, and the bubbles are proportional to the concentration of alcohol contained in the subject. The gas suction pipe enters the gas suction pipe with a certain amount of alcohol vapor, and the heat of reaction when this alcohol vapor oxidizes causes the temperature of the temperature-sensitive resistor in the gas suction pipe to rise and change its resistance value. It is said that the alcohol concentration in the sample is detected by measuring the alcohol concentration in the sample, and since it is equipped with a flow control means that controls the flow rate of air by adjusting the output pressure of the air supply means, continuous measurement is inherently possible. It is possible to carry out continuous measurement even if impurities are mixed into the specimen, and it can be used regardless of the depth of the liquid in the specimen, and has extremely high accuracy.

[Brief explanation of drawings]

FIG. 1a is a sectional view of an alcohol concentration detection device according to a first embodiment of the present invention. FIG. 1b is a sectional view of an alcohol concentration detection device according to a second embodiment of the present invention. FIG. 2 is a characteristic curve diagram showing the relationship between the immersion depth in the sample and the measured value of the alcohol concentration detection device according to the embodiment of the present invention. FIG. 3 is a sectional view of an alcohol concentration detection device according to the prior art. FIG. 4 is a sectional view of another alcohol concentration detection device according to the prior art. DESCRIPTION OF SYMBOLS 1... Subject, 2... Box-shaped object, 3... Ventilation vibrator, 4... Exhaust pipe, 6... Gas sensor, 7... Gas sampling tube, 8... Temperature sensor, 9... Ventilation pump, 10... Test liquid, 20... Upper end closing member, 21... Cylindrical member, 211... Upper end of the cylindrical member, 212... Lower end of the cylindrical member , 22...Gas supply pipe, 221...Lower end of gas supply pipe, 24...Air supply means, 26...Gas suction pipe, 261...Gas flow rate detection means, 27...Gas temperature Detection means, 28... Gas temperature change detection means, 29... Temperature change/alcohol concentration correction means, 30.
... Alcohol concentration output means, 31 ... Flow rate control means, 32 ... Test liquid temperature detection means, 321 ... Test object temperature sensor, 33 ... Gas temperature change detection means, 34 ... Standard Value, 35... Support, 36... Tank.

Claims (1)

[Scope of Claims] [1] A cylindrical member (21) whose upper end (211) is closed with an upper end closing member (20) and whose lower end (212) is an open end; and the upper end closing member (20). The cylindrical member (
21), its lower end (221) ends above the lower end (212) of the cylindrical member (21), and has an air supply means (24), the lower end of which is suspended in the test liquid. a gas supply pipe (22) immersed in the gas supply pipe (22) and the upper closing member (22);
a gas suction pipe (26) provided to penetrate through the gas suction pipe (26); a gas temperature detection means (27) provided in the gas suction pipe (26) for detecting the temperature of the gas; a gas temperature change detection means (28) for detecting a temperature change of the gas based on the temperature detected by the gas temperature change detection means (27); and a temperature change/alcohol concentration correction means (29) for correcting the temperature change of the gas to a test alcohol concentration. ), and an alcohol concentration output means (30) for outputting information representing the corrected alcohol concentration, the gas flow rate detection means (30) for detecting the gas flow rate flowing through the gas suction pipe (26). 261), and a flow rate control means (31) for controlling the amount of gas flowing through the gas supply pipe (22) in response to a deviation between the flow rate of the gas flow rate detection means (261) and a reference value. Characteristic alcohol concentration detection device. [2] A cylindrical member (21) whose upper end (211) is closed with an upper end closing member (20) and whose lower end (212) is an open end; Cylindrical member (
21), its lower end (221) ends above the lower end (212) of the cylindrical member (21), and has an air supply means (24), the lower end of which is suspended in the test liquid. a gas supply pipe (22) immersed in the gas supply pipe (22) and the upper closing member (22);
a gas suction pipe (26) provided through the gas suction pipe (26), a gas temperature detection means (27) provided in the gas suction pipe (26) for detecting the temperature of the gas, and the upper closing member (20). ), and the lower end of the cylindrical member (21) (
221) A test liquid temperature detection means (32) provided nearby and having a test object temperature sensor (321) for detecting the temperature of the liquid containing the test alcohol, and detecting the test liquid temperature and the gas temperature. a gas temperature change detection means (33) that compares and detects a temperature change of the gas; a temperature change/alcohol concentration correction means (29) that corrects the temperature change of the gas to a test alcohol concentration; an alcohol concentration output means (30) for outputting information representing the alcohol concentration of the gas; Alcohol concentration detection characterized by comprising a flow rate control means (31) that controls the amount of gas flowing through the gas supply pipe (22) in response to a deviation between the flow rate of the flow rate detection means (261) and a reference value. Device.