JPH02259550A - Alcohol concentration detector - Google Patents

Abstract

PURPOSE:To obtain the inexpensive detector by refracting the light from a light emitting member at the refractive index corresponding to the alcohol concn. when the light is transmitted through an alcohol-contg. soln. as the material to be measured and sending the light to a light receiving member. CONSTITUTION:The light emitting member 3 having a light emitting element 3a, a light emitting fiber 3b connected to the element 3a and a light emitting part 3c consisting of a transparent window provided on a wall surface 2. The light receiving member 4 has a light receiving element 4a, a light receiving fiber 4b connected to the element 4a and a light receiving part 4c consisting of a transparent window furnished on the wall surface. The light receiving part 4c is shifted from the position on the wall surface 2 opposed to the light emitting part 3c by a specified distance and positioned obliquely to the light emitting part 3c. The alcohol-contg. soln. 1 is charged into the storage member and placed between the wall surfaces 2. When the light from the light emitting member 3 is transmitted through the soln. 1 as the material to be measured, the light is refracted at a refractive index corresponding to the alcohol concn. and sent to the light receiving member 4.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an alcohol concentration detector, and particularly to an alcohol concentration detector that detects alcohol concentration by changing the refractive index of light transmitted through an alcohol-containing solution. It is related to.

[Prior Art and Problems to be Solved] Conventionally, as a means for detecting the alcohol concentration in an alcohol-containing solution in which alcohol is mixed in a solution such as gasoline, there has been known a method that utilizes changes in light transmittance. There is.

That is, detection windows are provided on opposing walls of a storage member that stores an alcohol-containing solution inside, one detection window is provided with a light emitting member such as a light source, and the other detection window is provided with a photocell or the like. A light-receiving member is provided, light is incident from the light-emitting member into the alcohol-containing solution, and the alcohol concentration in the alcohol-containing solution is detected by the change in energy of the light transmitted through the alcohol-containing solution by the light-receiving member. It is.

In this case, at the detection window on the side that receives the transmitted light,
If the light that reaches the light receiving member deviates from the position of the light receiving member, the energy change of the transmitted light cannot be measured accurately. Therefore, parallel light is appropriate as the incident light, and the light from the light source cannot be treated as parallel light. Collimating lenses, etc., were used.

However, when the collimating lens and the like are installed in an alcohol concentration detector using the above means, the structure of the alcohol concentration detector becomes complicated, the detection accuracy deteriorates due to vibration, and furthermore, the collimating lens itself is expensive. Therefore, there was a problem in that the detector was also expensive.

The present invention solves the above problems, has a simple structure, and
The purpose of this invention is to provide an alcohol concentration detector that is cheaper than conventional ones.

[Means to solve the problem]

In order to solve the above problems, the present invention includes a light-emitting member and a light-receiving member that receives light emitted by the light-emitting member and transmitted through the alcohol-containing solution, on the wall surface of a storage member that stores an alcohol-containing solution. The light-emitting member includes a light-emitting element and a light-emitting fiber connected to the light-emitting element, and the light-receiving member includes a light-receiving fiber that receives light transmitted through the alcohol-containing solution, and a light-receiving fiber connected to the light-receiving fiber. and a means comprising an element.

[Effect]

By employing the above-mentioned means, the present invention allows the light from the light-emitting member to reach the light-receiving member after being refracted with a refractive index according to the alcohol concentration when passing through the alcohol-containing solution that is the object to be measured. Become.

〔Example〕

Embodiments of the present invention shown in the drawings will be described below.

FIG. 1+a) shows a first embodiment of an alcohol concentration detector according to the invention, which comprises a luminescent member 3 attached to a wall 2 of a reservoir member into which an alcohol-containing solution 1 is placed. and a light-receiving member 4 attached to the wall surface 2 facing the wall surface 2, the light-receiving member 4
A calculation means IO is connected to.

The light emitting member 3 includes a light emitting element 3a (for example, a light emitting diode) and a light emitting fiber 3 connected to the light emitting element 3a.
b, and a light-emitting portion 3C made of a transparent window or the like attached to the wall surface 2 and in contact with the end of the light-emitting fiber 3b.

The light-emitting member 4 includes a light-receiving element 4a (for example, a photodiode), a light-receiving fiber 4b connected to the light-receiving element 4a, and a transparent light-receiving fiber 4b that is in contact with the end of the light-receiving fiber 4b and attached to the wall surface 2. It has a light receiving section 4C consisting of a window.

The light receiving section 4C is mounted on the wall surface 2 at a position that is offset by a predetermined distance from a position facing the light emitting section 3C, and is located diagonally to the light emitting section 3C.

To detect alcohol concentration using the alcohol concentration detector configured as described above, first, the storage member (
(not shown), put the alcohol-containing solution 1 into the wall surface 2.
Alcohol-containing solution 1 is present between 0 and 0.

Then, when the light emitting element 3a is made to emit light and light is irradiated from the light emitting part 3C to the alcohol-containing solution 1 between the wall surfaces 2.2 through the light emitting fiber 3b, the irradiated light is transmitted from the light emitting part 3C to the light receiving part 4C. It passes through the alcohol-containing solution 1 and reaches the wall surface 2 on which it is attached.

At that time, alcohol-containing solutions 1 with different alcohol concentrations
, the refractive index of light differs, and the amount of received light energy reaching the light receiving section 3C changes.

For example, as alcohol-containing solution 1, FIG. 5 shows the relationship between the refractive index of light transmitted through a gasoline solution and its alcohol concentration.

In Fig. 5, graph 1 and graph ■ indicate alcohol-containing premium gasoline solution, graph ■ and graph ■
shows a regular gasoline solution containing alcohol, and the refractive index of light according to each alcohol concentration was measured at 23°C for graphs ■ and 2 and 40°C for graphs ■ and ■. Therefore, as shown in FIG. 1 (al), the light that passes through the low alcohol concentration solution with a low alcohol concentration becomes the one shown by the optical path 5, and the light that passes through the high concentration alcohol containing solution with a high alcohol concentration. The light becomes as shown by the optical path 6.

In addition, as shown in the first opening), the received light energy that passes through the low-concentration alcohol-containing solution along the optical path 5 and reaches the wall surface 2 on which the light receiving part 4C is attached is as shown in the 11 distribution curve 7. The received light energy that passes through the high concentration alcohol-containing solution along the optical path 6 and reaches the wall surface 2 on which the light receiving section 4C is attached is as shown by the distribution curve 8.

FIG. 1 (C1 shows an enlarged view of the main part of FIG. 1(b), and shows the amount of received light energy that enters the light receiving section 4C, and the amount of light energy that passes through the low concentration alcohol-containing solution and enters the light receiving section 4C.
The amount of received light energy incident on c corresponds to the area surrounded by the distribution curve 7 and the light receiving section 4c, and the amount of received light energy that passes through the high concentration alcohol-containing solution and enters the light receiving section 4C corresponds to the area surrounded by the distribution curve 7 and the light receiving section 4c. 8 and the light receiving section 4C.

Here, the positions at which the light emitting section 3c and the light receiving section 4C are attached to the wall surface 2 have different distribution curves 7.8, so the positions where the change in the amount of light received incident on the light receiving section 4C is increased are determined as follows. Rather than being provided at the same height position on the wall surfaces 2 facing each other, the light receiving section 4C is placed at a slightly lower position to face the light emitting section 3C.

The light receiving element 4a then outputs a signal corresponding to the amount of received light energy transmitted to the calculation means 10 connected to the light receiving element 4a.

Calibration curve data of the relationship between the amount of received light energy and the alcohol concentration corresponding to each alcohol-containing solution with each known alcohol concentration is inputted in advance to this calculation means 10, and the data corresponds to the signal from the light-receiving element 4a. The alcohol concentration of the alcohol-containing solution 1, which is the sample, can be determined from the amount of received light energy.

FIG. 2ta) shows a second embodiment of an alcohol concentration detector according to the invention, which comprises a wall 22 of a reservoir member into which an alcohol-containing solution l is placed.
The light-emitting member 23 is attached to the wall surface 22, and the light-receiving member 24 is attached to the wall surface 22 facing the wall surface 22. The light-receiving member 24 is connected to a calculation means 30.

The light emitting member 23 includes a light emitting element 23a and a light emitting element 2.
3a, and a light emitting part 23c made of a transparent window or the like attached to the wall surface 22 and in contact with the end of the light emitting fiber 23b. It is attached to the wall surface 22 with an incident angle of θ relative to the perpendicular to the wall surface 22.

The light-emitting member 24 includes a light-receiving element 24a, a light-receiving fiber 24b connected to the light-receiving element 24a, and a transparent window that abuts the end of the light-receiving fiber 24b and is attached to the wall surface 22. It has a portion 24c.

Further, the light receiving section 24c is mounted on the wall surface 22 at a position facing the light emitting section 23c, shifted by a predetermined distance, and is positioned diagonally to the light emitting section 23c.

Using the alcohol concentration detector configured as described above, in the same manner as in the first embodiment, an incident angle θ is set from the light emitting unit 23 to the alcohol-containing solution l from the light emitting element 23a via the light emitting fiber 23'b. When irradiated with light, the irradiated light passes through the alcohol-containing solution 1 and reaches the wall surface 22 to which the light receiving section 24C is attached from the light emitting section 23c.

At that time, alcohol-containing solutions 1 with different alcohol concentrations
, the refractive index of light differs, and the amount of light received reaching the light receiving section 23C changes.

Therefore, as shown in FIG. 2 Ta), the light that passes through the low concentration alcohol-containing solution is as shown by the optical path 25, and the light that passes through the high-concentration alcohol-containing solution is as shown by the optical path 26. becomes.

In addition, as shown in the second opening), the received light energy that passes through the low concentration alcohol-containing solution along the optical path 25 and reaches the wall surface 22 on which the light receiving section 24c is attached is as follows:
The received light energy that passes through the high concentration alcohol-containing solution along the optical path 26 and reaches the wall surface 22 on which the light receiving section 24e is attached is as shown by a distribution curve 27, and is shown by a distribution curve 28.

Here, since the light is irradiated onto the alcohol-containing solution 1 with an incident angle θ, the optical path 25, 26 is entirely moved due to the change in the refractive index.

FIG. 2 tc+ shows an enlarged view of the main part of FIG. 27 and the light receiving portion 24c, and in the case of the high concentration alcohol-containing solution, it corresponds to the area surrounded by the distribution curve 28 and the light receiving portion 24C.

In this case, as shown in the first embodiment, when the incident angle is 90''', the optical path 5.6 does not change much even if the refractive index changes; Since the optical paths 25 and 26 irradiated onto the alcohol-containing tl*1 with θ move significantly as a whole, the light receiving section 24
The amount of received light energy detected by C has a larger variation than that in the first embodiment.

The light receiving element 24a then outputs a signal corresponding to the transmitted amount of received light energy to the calculation means 30 connected to the light receiving element 24a.

Calibration curve data of the relationship between the amount of received light energy and the alcohol concentration corresponding to the alcohol-containing solution of each alcohol concentration known in advance in the first embodiment and the same machine is input to this calculation means 30, The light receiving element 2
Since the signal corresponding to the amount of light energy received from 4a has a larger variation than that in the first embodiment, the alcohol concentration can be detected more accurately than in the first embodiment.

FIG. 3 (al) shows a third embodiment of an alcohol concentration detector according to the present invention, in which a wall surface 32 of a reservoir member containing an alcohol-containing solution l is shown.
The light-emitting member 33 is attached to the wall surface 32, and the light-receiving member 34 is attached to the wall surface 32 facing the wall surface 32. The light-receiving member 34 is further connected to a calculation means 40.

The light-emitting member 33 includes a light-emitting element 33a, a light-emitting fiber 33b connected to the light-emitting element 33a, and a light-emitting section that abuts the end of the light-emitting fiber 33b and is attached to the wall surface 32, such as a transparent window. 33c.

The light-receiving member 34 includes a light-receiving element 34a, a light-receiving fiber 34b connected to the light-receiving element 34a, and a transparent window that abuts the end of the light-receiving fiber 34b and is attached to the wall surface 32. Light receiving section 34
It has C.

The light receiving section 34C has a conical shape with the bottom surface facing the alcohol-containing solution 1, and is located diagonally to the light emitting section 33C on the wall surface 32.

Using the alcohol concentration detector configured as described above, the alcohol-containing solution 1 is irradiated with light from the light emitting unit 33c via the light emitting element 33a and the light emitting fiber 33b.

Then, the irradiated light is transferred from the light emitting section 33c to the light receiving section 34.
Apply alcohol-containing solution ff1 to the wall surface 32 where c is attached.
Reach it by passing through 1.

In this case, alcohol-containing solutions with different alcohol concentrations
, the refractive index of light differs, and the amount of light received reaching the light receiving section 34C changes.

Therefore, as shown in FIG. 3(al), the light that passes through the low concentration alcohol-containing solution is as shown by the optical path 35, and the light that passes through the high-concentration alcohol-containing solution is as shown by the optical path 36. becomes.

In addition, as shown in the third opening), the received light energy that passes through the low concentration alcohol-containing solution along the optical path 35 and reaches the wall surface 32 on which the light receiving section 34c is attached is as follows:
The received light energy that passes through the high-concentration alcohol-containing solution along the optical path 36 and reaches the wall surface 32 on which the light receiving section 34c is attached is as shown by a distribution curve 37, and is shown by a distribution curve 38.

FIG. 3 ic) shows an enlarged view of the main part of the third opening), and shows the amount of received light energy incident on the light receiving part 34c, and in the case of the low concentration alcohol-containing solution, the distribution surface vA37 In the case of the high concentration alcohol-containing solution, it corresponds to the area surrounded by the distribution surface &113B and the light receiving part 34c.

In this case, the light receiving section 34C has a conical shape, and the light receiving area is larger than that of the first embodiment, so the amount of received light energy is larger than that of the first embodiment. Become.

Then, the light receiving element 34a outputs a signal corresponding to the transmitted amount of received light energy to the calculation means 40 connected to the light receiving element 34a.

As in the first embodiment, calibration curve data of the relationship between the amount of received light energy and the alcohol concentration corresponding to the alcohol-containing solution of each known alcohol concentration is input into the calculation means 40, The light receiving element 3
Since the signal corresponding to the amount of light energy received from 4a has a larger variation than that in the first embodiment, the alcohol concentration can be detected more accurately than in the first embodiment.

FIG. 4 ta+ shows a fourth embodiment of an alcohol concentration detector according to the present invention, in which a wall surface 42 of a reservoir member into which an alcohol-containing solution l is placed.
The light-emitting member 43 is attached to the wall surface 42, and the light-receiving member 44 is attached to the wall surface 42 facing the wall surface 42. Further, the light-receiving member 44 is connected to a calculation means 50.

The light-emitting member 43 includes a light-emitting element 43a, a light-emitting fiber 43b connected to the light-emitting element 43M, and a light-emitting section that abuts the end of the light-emitting fiber 43b and is attached to the wall surface 42, such as a transparent window. 43c.

The light-receiving member 44 contacts a light-receiving element 44a, a plurality of light-receiving fibers 44b (three in the drawing) connected to the light-receiving element 44a, and an end of the light-receiving fibers 44b, and also contacts the wall surface 42. A plurality of light receiving sections 44c (three in the drawing) consisting of attached transparent windows, etc.
It has

Using the alcohol concentration detector configured as described above, the alcohol-containing solution 1 is irradiated with light from the light emitting element 43a via the light emitting fiber 43b and from the light emitting section 43C in the same manner as in the first embodiment.

Then, the irradiated light is transferred from the light emitting section 43c to the light receiving section 44.
It passes through the alcohol-containing solution 1 and reaches the wall surface 42 where c is attached.

At that time, alcohol-containing solutions 1 with different alcohol concentrations
, the refractive index of light differs, and the amount of light received reaching the light receiving section 44C changes.

Therefore, as shown in FIG. 4(al), the light that passes through the low concentration alcohol-containing solution is as shown by the optical path 45, and the light that passes through the high-concentration alcohol-containing solution is as shown by the optical path 46. becomes.

Further, as shown in FIG. 4(b), the light is transmitted through the 1R solution containing low concentration alcohol as shown in the optical path 45, and the light receiving portion 44
The received light energy reaching the wall surface 42 where the light receiving section 44c is attached is as shown in the distribution curve 47, and passes through the high concentration alcohol-containing solution along the optical path 46 and reaches the wall surface 42 where the light receiving section 44c is attached. The received light energy is as shown by a distribution curve 48.

FIG. 4 is an enlarged view of the main part of FIG. Corresponds to the area surrounded by the curve 47 and the light receiving part 44c,
In the case of the high-concentration alcohol-containing solution, this corresponds to the area surrounded by the distribution curve 48 and the light receiving section 44c.

That is, in this embodiment, the plurality of light receiving sections 4
4c, the light receiving area is larger than that of the first embodiment, and the amount of light receiving energy is larger than that of the first embodiment.

Then, the light receiving element 44a outputs a signal corresponding to the amount of received light energy to the calculation means 50 connected to the light receiving element 44a, as in the first embodiment.

As in the first embodiment, calibration curve data of the relationship between the amount of received light energy and the alcohol concentration corresponding to the alcohol-containing solution of each known alcohol concentration is input into the calculation means 50. The light receiving element 4
Since the signal corresponding to the amount of light energy received from 4a has a larger variation than that in the first embodiment, the alcohol concentration can be detected more accurately than in the first embodiment.

In the second embodiment, the light emitting section is attached to the wall surface at an incident angle .theta., but this incident angle .theta. can be arbitrarily selected.

Further, in the third embodiment, the light receiving section is formed into a conical shape whose bottom surface is the light receiving surface, but the shape is not limited to this.

Furthermore, in the fourth embodiment, three light-receiving fibers and three light-receiving parts are used for one light-receiving element, and the light-receiving area is tripled. All you have to do is do it.

〔Effect of the invention〕

By having the above configuration, the present invention allows the amount of light transmitted from the same light emitting source to pass through the alcohol-containing solution to the light-receiving section to change depending on the alcohol concentration of the alcohol-containing solution that is the object to be measured. The alcohol concentration changes in accordance with the rate change, and this change allows the alcohol concentration to be measured, and since the emission of light into and reception of light from the alcohol-containing solution is transmitted via an optical fiber, This has excellent effects such as the structure of the detector is simple, remote detection is possible using an optical fiber, and it can be manufactured at low cost.

[Brief explanation of drawings]

Figure 1! a) is a diagram showing an outline of the first embodiment of the alcohol concentration detector according to the present invention, FIG.
Figure [b] is an enlarged view of the main part, Figure 2 (a) is a diagram showing an outline of the second embodiment of the alcohol concentration detector according to the present invention, and (in Figure 2) is the light reception distribution in the second embodiment. A diagram showing the curve, Figure 2 (C1 is an enlarged view of the main part of Figure 2 (bl, Figure 3 f)
a) is a diagram showing an outline of the third embodiment of the alcohol concentration detector according to the present invention, FIG. 3 (bl is a diagram showing a light reception distribution curve in the third embodiment, and FIG. b)
An enlarged view of the main part of FIG. 4 (al is a diagram showing an outline of the fourth embodiment of the alcohol concentration detector according to the present invention, in FIG. 4)
is a diagram showing the light reception distribution curve in the fourth embodiment, FIG. 4 (C1 is an enlarged view of the main part of FIG. 4(b), and FIG. It is a diagram showing the relationship. 1... Alcohol-containing solution 2.22.32.42... Wall surface 3.23.33
．． 43... Light emitting member 3a-, 2, 3as 33
a, 43a... Light emitting elements 3b, 23b. 33b, 43b... Light emitting fibers 3c, 23c
, 33c, 43cm --- Light emitting section 4.24.34.
44... Light receiving member 4a, 24a, 34a, 44
a... Light receiving elements 4b, 24b. 34b, 44b... Light receiving fibers 4c, 24c
, 34cs 44c... Light receiving section 5, 6, 2
5, 26. 35.36.45.46... Light path 7, 8,
27, 28. 37.38.47.48...Distribution curve 10.3
0, 40.50...Calculating means ■, ■, ■, ■・
...Graph 2nd Figure 5eo 60 40 20

Claims (1)

[Scope of Claims] (1) A light-emitting member (3
)(23)(33)(43) and the light emitting members (3)(2
3) (33) (43) and the alcohol-containing solution (
1) Light receiving members (4) (24) (
34) (44), and the light emitting members (3) (23) are arranged.
) (33) (43) are light emitting elements (3a) (23a) (33a) (43a) and light emitting elements (3a) (23a).
) (33a) A light emitting fiber (3b) connected to (43a)
) (23b) (33b) (43b), and the light receiving member (4) (24) (34) (44) includes a light receiving fiber (4b) (44) that receives the light transmitted through the alcohol-containing solution (1).
24b) (34b) (44b) and a light-receiving element (4b) (24b) (34b) (44b) connected to the light-receiving fiber (4b)
4a) (24a) (34a) (44a).