JP2727146B2 - Chromaticity monitor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chromaticity monitor for monitoring chromaticity of tap water or the like.

[0002]

2. Description of the Related Art One of water quality test items such as tap water is chromaticity of water. To constantly monitor this, it has been proposed to install a chromaticity monitor in the middle of the pipe of tap water.

In this type of chromaticity monitor, the detecting section is composed of a light projecting section and a light receiving section, and the space between the two is filled with the liquid to be measured and the tristimulus of light transmitted through the liquid to be measured detected by the light receiving section. The chromaticity is calculated from the value.

[0004]

Since a chromaticity monitor has a temperature drift characteristic in which a chromaticity reference value varies with temperature, it is necessary to calibrate the reference chromaticity every time the chromaticity is measured. .

[0005] Distilled water is used as the liquid having the standard chromaticity, and air is used instead. When using distilled water, at the time of measurement, first, for calibration of the reference chromaticity, perform calibration of the reference chromaticity by draining the liquid between the light emitting unit and the light receiving unit of the detection unit and filling with distilled water, Then, the liquid to be measured is filled first, distilled water is drained, and then the liquid to be measured is filled, and the chromaticity measurement is started. Therefore, in order to constantly monitor the chromaticity on-line, the complicated operation described above must be frequently repeated, and maintenance work such as constantly supplying distilled water is troublesome.

When the reference chromaticity is calibrated using air instead of distilled water, the operability is improved because only the operation of removing and refilling the liquid to be measured filled in the detection section is required. There is a problem in that the difference in the amount of light received by the light receiving unit becomes large due to the difference in the refractive index between the measurement liquid and air, and the measurement accuracy is reduced.

An object of the present invention is to solve the above problems.

[0008]

Means for Solving the Problems The present invention solves the above-mentioned problems, and accommodates a liquid to be measured in a chromaticity monitor that determines the chromaticity of the liquid to be measured from the spectral characteristics of light transmitted through the liquid to be measured. Container, a light projecting unit arranged on the wall surface of the container, a light receiving unit arranged on the wall surface of the container at a position for receiving light projected from the light projecting unit, and movably into the container. The arranged optical element and the calibration data are calculated based on the light transmitted through the optical element, and the chromaticity data of the measured liquid is calculated based on the light transmitted through the measured liquid. Chromaticity measuring means for correcting final chromaticity by correcting the corrected chromaticity data with the calibration data, and inserting the optical element between the light emitting unit and the light receiving unit when calculating the calibration data At the time of measuring the chromaticity of the liquid to be measured. Optical element moving means for retracting the optical element from the insertion position.

The optical element can be made of a material such as glass or synthetic resin, and is preferably made of a material having a spectral transmission characteristic close to the spectral transmittance of the liquid to be measured.

[0010]

The chromaticity measuring means calculates calibration data based on the light transmitted through the optical element, and calculates chromaticity data of the measured liquid based on the light transmitted through the measured liquid, and calculates the calculated color. The chromaticity data is corrected by the calibration data to determine the final chromaticity. The optical element movably disposed in the container moves to the insertion position between the light emitting part and the light receiving part when calculating the calibration data, and retreats from the insertion position when measuring the chromaticity of the liquid to be measured, and projects the light. The liquid to be measured is filled between the light part and the light receiving part.

[0011]

Embodiments of the present invention will be described below.

FIG. 1 shows a chromaticity monitor embodying the present invention.
FIG. 2 is a perspective view schematically showing the configuration of FIG.
0 indicates a detection unit, 200 indicates a photoelectric conversion unit, and 300 indicates a data processing unit.

The detecting section 100 includes a container 1 containing the liquid S to be measured, a light projecting section 2 and a light receiving section 3 provided on a side wall thereof, and a glass inserted between the light projecting section 2 and the light receiving section 3. And an optical element 5 having a predetermined spectral transmission characteristic made of a light-transmitting material such as a synthetic resin.

The optical element 5 can be moved in the direction of arrow a via a plunger 9 and a frame 8 which reciprocate by a drive mechanism (not shown). It is set at the insertion position between the light receiving section 3 and the chromaticity measurement of the liquid S to be measured.
It is configured to be set at a retracted position outside the insertion position.

The light projecting unit 2 includes a photoelectric conversion unit 2 described later.
The light projected from the light source L provided in the light source 00 is guided through the optical fiber 6 and projected toward the light receiving unit 3.
The light received by the light receiving section 3 is guided via an optical fiber 7 to a later-described photo diode provided in a later-described photoelectric conversion section 200. Further, the container 1 is configured to be constantly filled with a liquid to be measured whose chromaticity is to be monitored, here tap water, by a liquid to be measured supply means (not shown).

FIG. 2 is a circuit block diagram of the chromaticity monitor, which comprises a photoelectric conversion unit 200 and a data processing unit 300.

The photoelectric conversion unit 200 measures the chromaticity of the liquid S to be measured and outputs measurement data. The photoelectric conversion unit 200 measures the light source L and outputs the reference data. Consists of This is because by obtaining the ratio between the measured value of the liquid S to be measured and the measured value of the light source L, the measurement error based on the fluctuation of the light source L or the like is canceled to always obtain a stable measurement result. Each of the sample measuring unit and the light source measuring unit includes three series of circuits for decomposing the measured light into three basic components for processing.

The sample measuring units are photodiodes P1 to P
3. Filters F1 to F3 for separating detection light arranged in front of the photodiode into basic color components, and a photoelectric conversion circuit E
1 to E3, gates G1 to G3, sample hold circuit H
1 to H3 and gates G7 to G9. Further, the light source measuring unit includes the photodiodes P4 to P6, filters F4 to F6 disposed in front of the photodiodes for decomposing the detection light into basic color components, photoelectric conversion circuits E4 to E6, gates G4 to G6, It is composed of sample hold circuits H4 to H6 and gates G10 to G12.

The data processing unit 300 includes a central processing unit (CP)
U) 22, a ROM 23 connected to the CPU 22 for storing a control program, a color conversion program, etc., a RAM 24 for temporarily storing arithmetically processed color information and the like, a control clock signal generator 25, an input to the CPU 22 and peripheral devices. I / O control unit 27 for controlling the output, display unit 28 for displaying and printing the measurement results connected to I / O control unit 27, warning unit 2
9, the keyboard 30, the gates G1 to G6, and the insertion position and retreat of the optical element 5 of the detecting unit 100 between the light projecting unit 2 and the light receiving unit 3 in response to the switching signal of calibration / measurement. Optical element drive circuit 3 for driving a drive mechanism (not shown) for moving the optical element to a position
1 and an illumination circuit 32 for controlling the lighting of the light source L.

Next, the operation will be described with reference to the flowcharts of FIGS.

First, the container 1 of the detection unit 100 is filled with the liquid to be measured, and a series of processes such as turning on the power, loading a program, and initializing are executed to set the apparatus in an operable state. The processing is executed in the order of the chromaticity reference calibration processing and the chromaticity measurement processing of the liquid to be measured.

First, the chromaticity reference calibration process will be described. The flowchart of FIG. 3 shows the calibration process based on the chromaticity. The tristimulus values X0, Y0, which are the standard values of the chromaticity of the optical element 5 to be used as the reference for calibration from the keyboard 30. Z0 is input (step P1). The optical element 5 is set at the insertion position between the light projecting unit 2 and the light receiving unit 3 (step P2), the light transmitted through the optical element 5 is detected, and the detection signal is used as a tristimulus value calculation rule described later. The tristimulus values Xm, Ym and Zm indicating the chromaticity of the optical element 5 are calculated by the chin (step P3).

Next, the calibration constants α0 and β0 are calculated by the following equations.
, Γ0 (step P4), and the calibration constants α0, β0, γ0 obtained by calculating α0 = X0 / Xmβ0 = Y0 / Ymγ0 = Z0 / Zm are stored in the RAM 24.
(Step P5).

Next, the process of measuring the chromaticity of the liquid to be measured will be described. The flowchart of FIG. 4 shows a process for measuring the chromaticity of the liquid to be measured. The optical element 5 at the insertion position between the light projecting unit 2 and the light receiving unit 3 is moved to the retracted position and set. The liquid S to be measured is filled between the light projecting unit 2 and the light receiving unit 3 (step P).
11) The light transmitted through the liquid S to be measured is detected, and the detected signal is calculated by a tristimulus value calculation routine described later, and the tristimulus values Xs, Ys, and Zs indicating the chromaticity of the liquid S to be measured. (Step P12).

The calibration constant α0 stored in the RAM 24
, Β0, and γ0 are read out (Step P13), and are corrected by multiplying the measured tristimulus values Xs, Ys, and Zs indicating the chromaticity of the liquid S to be measured by calibration constants α0, β0, and γ0 (Step P14). The corrected tristimulus values X, Y, and Z indicating the chromaticity of the liquid S to be measured are color-space-converted to a color system designated by known means (step P15), and displayed on the display unit 28, Printing is performed (step P16), and the process ends.

Next, step P3 of the flowchart shown in FIG. 3 and step P1 of the flowchart shown in FIG.
The tristimulus value calculation routine shown as 2 will be described with reference to the flowcharts shown in FIGS.

First, a reset signal for resetting the sample hold circuits H1 to H6 is turned on, and after a predetermined time has passed, the reset signal is turned off (step P21).
~ Step P23). As a result, the sample hold circuits H1 to H6 enter the reset state. The gates G1 to G6 are turned on, the lighting circuit 32 is turned on, and the light source L is turned on (step P24). The light transmitted through the optical element 5 at the time of calibration and the light transmitted through the liquid S to be measured at the time of measurement are filtered by the filter F1.
Through F3 to be separated into basic color components, detected by photodiodes P1 to P3, amplified by photoelectric conversion circuits E1 to E3, and passed through gates G1 to G3 to sample hold circuits H1 to H3. It is held. Further, in order to obtain a fluctuation correction signal of the light source L, the light projected from the light source L is directly transmitted through the filters F4 to F6, decomposed into basic color components, detected by the photo diodes P4 to P6, and detected by the photo diodes P4 to P6.
It is amplified at 4-E6 and is held at sample-hold circuits H4-H6 via gates G4-G6.

After a predetermined time required for completing the above processing has elapsed (step P25), the gates G1 to G6 are turned off.
F, and the lighting circuit 32 is turned off (step P2).
6). The coefficient i designating the gate number is set to 7 (step P27), and the counter provided in the CPU is reset (step P28). Gate Gi (Initially Gate G
7) is turned ON, and the data held by the sample hold circuit Hi is output to the A / D converter 21 (step P29).

It is determined whether or not the output of the A / D converter 21 is "H". If the output is not "H", the content of the counter is incremented by 1 (steps P30 and P31). A / D converter 21
Is "H", the output data Ci of the A / D converter 21 is stored in the register of the CPU (step P3).
2). The gate Gi is turned off (step P33), and whether or not the coefficient i has exceeded 12, that is, the gates G7 to G12
Are sequentially opened and it is determined whether or not the processing has been completed for all the data held in the sample hold circuits H1 to H6. If i ≦ 12, the process returns to step P29 and i>
In the case of 12, the process proceeds to the next process (step P34).

Reset of sample hold circuits H1 to H6, ON / OFF of certification circuit 32, and gates G1 to G6
FIG. 7 shows ON / OFF of the gates G7 to G12 and the operation timing of the A / D converter 21.

The processing in steps P35 to P48 is based on the light source L
In the state where is not lit, the light transmitted through the optical element 5 during calibration, the light transmitted through the liquid S to be measured during measurement is measured, and the output data is stored in a register of the CPU. Since the processing is the same as the processing in steps P21 to P34 described above, a detailed description is omitted. Here, the output data of the output data A / D converter 21 is identified as Di.

In the above process, data C1 to C6 measured with the light source L turned on and data D1 to D6 measured without the light source L turned on are stored in the register of the CPU. Will be.

In step P49, intermediate values A (1) to A (6) are obtained by performing calculations according to the following formulas.

A (1) = C (1) -D (1) (1) A (2) = C (2) -D (2) (2) A (6) = C (6) -D (6) (6) Next, step P50 The following calculation for correcting the fluctuation of the light source L is executed by using the tristimulus values Xm, Ym, and Z of the optical element 5.
m or the tristimulus values Xs, Ys, Zs of the liquid S to be measured are obtained, and the process is terminated.

Xm (Xs) = A (1) / A (4) (7) Ym (Ys) = A (2) / A (5) (8) Zm (Zs) = A ( 3) / A (6) (9) FIG. 8 is a diagram schematically showing the configuration of a remote monitoring system for a chromaticity monitor embodying the present invention.
Is a detection unit, 200 is a photoelectric conversion unit, 300 is a data processing unit, 400 is a measurement control unit, 500 is an optical element drive operation unit, 600 is a telephone with a built-in modem, 700 is a general public line (telephone line), and 800 is 3 shows a control monitoring panel.

The measurement control unit 400 instructs the optical element drive operation unit 500 and the data processing unit 300 to start measurement at regular time intervals. The data processing unit 300 measures the tristimulus values and the like of the liquid to be measured according to the determined order as described above,
The calculation is performed according to various colorimetric modes, and the result is stored. The colorimetric mode is converted into a chromaticity correlation number by the measurement control unit 400 by an arithmetic expression for comparison with the chromaticity frequency of the analysis method using the previously obtained standard solution.

The converted chromaticity correlation number is subjected to data processing, and then transmitted from the telephone 600 with a built-in modem to the control and monitoring panel 800 via the general public telephone line 700 and the like, converted into a positive chromaticity, and recorded and displayed. .

FIG. 9 shows the configuration of the detection unit 100 shown in FIG. A pipe 101 for introducing the liquid to be measured is connected to one end of the container 1, and a stop valve 103, a pressure reducing valve 104, a check valve 10 are provided between the liquid introduction port 102 and the container 1.
5 are provided. On the other hand, the other end of the container 1 has a tube 106
Is connected, and the measured liquid to be measured is discharged from the discharge port 109 via the pipe 106. An electromagnetic valve 107 and a stop valve 108 are provided between the container 1 and the discharge port 109.

An optical element 5 is inserted into the container 1 and is connected to a driving device 150 outside the container 1 via a plunger 9. A dog 153 is provided on the plunger 9 protruding outside the container 1, and the insertion position switch 151 and the retreat position switch 152 provided in the axial direction of the plunger 9 are mechanically kicked to the terminal board 501. Send electrical signals. A float switch 154 is provided at an upper portion of the container 1, and detects whether or not the container 1 is sufficiently filled with the liquid to be measured.

Next, the operation will be described with reference to FIGS.
This will be described with reference to a timing chart shown in FIG.

First, the operation of setting the initial conditions will be described with reference to the flowchart of FIG. Turn on the float switch 154
(Step P101), close the solenoid valve 107 (Step P101)
102), the insertion position switch 151 is turned off (step P103), the retreat position switch 152 is turned on (step P104), and the counter 502 is set to 0 (zero) (step P105).

Next, the measuring operation will be described with reference to the flowchart of FIG. The electromagnetic valve 107 is opened, the liquid to be measured is introduced into the container 1, and the liquid to be measured in the container 1 is exchanged by flowing for a predetermined time (steps P111 and P112). Next, the electromagnetic valve 107 is closed (step P113), the optical element 5 is reciprocated between the insertion position and the retreat position (the number of times is counted by the counter 502), and the liquid to be measured is stirred (steps P114 to P119). ). After four reciprocations, the optical element 5 is stopped at the insertion position, and the calibration value is measured by the optical element 5 (steps P120 to P121). The optical element 5 is returned to the retracted position, and the liquid to be measured is measured (steps P122 to P122).
P124). The measured values are sent to the data processing unit 300 and processed. When the above processing is completed, the solenoid valve 107 is closed, the insertion position switch 151 is turned off, the retreat position switch 152 is turned on, and the counter 502 becomes 0, thus completing one measurement.

[0043]

As described above, according to the chromaticity monitor of the present invention, the optical element is movably disposed in the container containing the liquid to be measured, and is used to calculate the calibration data. Calibration data is calculated based on the light transmitted through the optical element by moving to the insertion position between them, and when measuring the chromaticity of the liquid to be measured, the calibration data is retracted from the insertion position and the light is transmitted based on the light transmitted through the liquid to be measured. The chromaticity data of the measurement liquid is calculated, and the calculated chromaticity data is corrected by the calibration data to determine the final chromaticity. When the calibration data is calculated, the optical element in the container containing the liquid to be measured removes the liquid to be measured at the insertion position by the optical element, and when the chromaticity of the liquid to be measured is measured, the optical element is retracted to the insertion position. Since the liquid to be measured is filled, calculation of calibration data and measurement of chromaticity of the liquid to be measured can be performed quickly. For this reason,
Unlike the conventional equipment, it is not necessary to exchange the calibration reference solution such as distilled water and the solution to be measured each time calibration is performed. There is no need to constantly replenish the reference solution, and maintenance and management become easy, and the remarkable effect is achieved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a chromaticity monitor embodying the present invention.

FIG. 2 is a circuit block diagram of a chromaticity monitor.

FIG. 3 is a flowchart of a calibration process.

FIG. 4 is a flowchart of a measurement process.

FIG. 5 is a flowchart (part 1) of an arithmetic processing;

FIG. 6 is a flowchart (part 2) of an arithmetic processing.

FIG. 7 is a timing chart showing the timing of a control operation.
G.

FIG. 8 is a diagram schematically showing a configuration of a chromaticity monitor remote monitoring system.

FIG. 9 is a diagram schematically illustrating a configuration of a detection unit.

FIG. 10 is a flowchart for explaining an initial condition setting operation at the time of measurement.

FIG. 11 is a flowchart illustrating a measuring operation.

FIG. 12 is a timing chart for setting initial conditions and measuring operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container 2 Light-emitting part 3 Light-receiving part 5 Optical element 6, 7 Optical fiber 9 Plunger L Light source 100 Detection part 200 Photoelectric conversion part 300 Data processing part

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Nagahiro Shoji 1-12-19 Kitahorie, Nishi-ku, Osaka City Kurimoto Iron Works Co., Ltd. (56) References JP-A-59-44631 (JP, A) Hei 2-27227 (JP, A) Jiko 35-3998 (JP, Y1)

Claims (4)

(57) [Claims] 1. A chromaticity monitor for determining the chromaticity of a liquid to be measured from the spectral characteristics of light transmitted through the liquid to be measured, and a container for housing the liquid to be measured and a light projecting unit disposed on a wall of the container. When a light receiving portion <br/> disposed on the wall surface of the container at a position for receiving the light projected from the-projecting optical unit, an optical element which is movably disposed within said container, said optical element Calibration data is calculated based on the light transmitted through
On the other hand, based on the light transmitted through the liquid to be measured,
Calculate the chromaticity data of the measurement liquid and calculate the calculated chromaticity data
Is corrected by the calibration data to determine the final chromaticity.
Chromaticity measuring means, and when calculating the calibration data , move the optical element to an insertion position between the light projecting unit and the light receiving unit, and when measuring the chromaticity of the liquid to be measured , move the optical element to the insertion position. Evacuated from
Chromaticity, characterized in that an optical element moving means for
Monitor . 2. The chromaticity monitor according to claim 1, wherein said optical element is made of a glass material. 3. The chromaticity monitor according to claim 1, wherein said optical element is made of a synthetic resin material. 4. The chromaticity monitor according to claim 1, wherein said optical element is made of a material having a spectral transmittance characteristic close to a spectral transmittance of the liquid to be measured .