JPH10339697A - Lamp burnout detector of colorimetry analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To positively judge the state of lamp burnout by distinguishing the reduction of detection quantity of light to a photo detector, for example, due to the inclusion of muddy water from that due to the lamp burnout in a colorimetry analysis device. SOLUTION: Based on the absorbance of a sample that is obtained by transmitting light 3 from a light source 2 to a sample measurement cell 1 with a transmission window and by detecting the transmission light by a photo detector 4, the turbidity or chromaticity of the sample is measured by a colorimetry analysis device. The device has a judgment circuit 13 that judges the lamp burnout of the light source 2 based on a photo detector 12 for monitoring the quantity of light of the light source 2 and a signal from the photo detector 12 for monitoring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lamp burnout detecting device of a colorimetric analyzer.

[0002]

2. Description of the Related Art As shown in FIG. 5, a colorimetric analyzer transmits light 3 from a light source 2 to a sample measuring cell 1 having a transmission window, detects the transmitted light by a light receiving element 4, and detects the transmitted light. The turbidity and chromaticity of the sample are measured based on the absorbance of the sample obtained in step 5.

[0003] In such a colorimetric analyzer, the halogen lamp used for the light source 2 may burn out. For this reason, conventionally, when the amount of light detected by the light receiving element 4 falls below the lower limit of detection by the detection circuit 5 that receives a signal from the light receiving element 4, a lamp burnout alarm is generated on the assumption that a lamp burnout has occurred. Has emitted.

However, in this case, since there is a possibility that the amount of light temporarily decreases, it is necessary to repeat the operation of turning on and off the lamp to confirm whether or not the amount of light returns to the original amount. It confirms that it has run out and issues an alarm.

[0005]

However, when turbid water having turbidity and chromaticity exceeding the measurement range is mixed into the sample measuring cell 1, the light receiving element 4 is provided even though the lamp of the light source 2 is normal. May fall below the threshold for the lamp burn alarm. At this time, if the inflow of turbid water continues for a long time, there is a possibility that even if an operation of repeatedly turning on and off the lamp is performed, the lamp may be erroneously determined to be out and a warning may be issued.

In addition, the amount of light detected by the light receiving element 4 may decrease due to contamination of the sample measuring cell 1,
Also at that time, similarly, there is a possibility that the lamp is erroneously determined to be out of lamp and an alarm is issued.

Accordingly, the present invention distinguishes between a decrease in the amount of light detected on the light receiving element due to the mixing of turbid water and a decrease in the amount of light detected on the light receiving element due to the lamp being cut out, so that the state of lamp cut off can be reliably determined. The purpose is to do.

[0008]

In order to achieve this object, the present invention provides a sample measuring cell having a transmission window, wherein light from a light source is transmitted, and the transmitted light is detected by a light receiving element. Based on the absorbance, a colorimetric analyzer that measures the turbidity and chromaticity of the sample,
A light receiving element for monitoring a light quantity of a lamp of the light source is provided, and a determination circuit for determining whether the light source is out of the lamp based on a signal from the light receiving element for monitoring is provided.

With this configuration, the monitor light receiving element can detect only a decrease in the light amount of the lamp of the light source irrespective of the state of the sample water in the sample measurement cell, the degree of contamination of the sample measurement cell, and the like. , The detection of the lamp burnout can be performed.

Further, the present invention provides a means for guiding a monitor light from a light source to a light receiving element by bypassing a sample measurement cell, a sample measurement light passing through the sample measurement cell, and a monitor for the bypassed monitor. Means for selectively receiving light by the light receiving element, and a circuit for judging whether the lamp of the light source has run out based on a signal from the light receiving element when the light receiving element receives monitoring light. It is like that.

With such a configuration, it is possible to detect a lamp burnout using only the original light receiving element without specially providing the monitoring light receiving element as described above. Further, according to the present invention, the detected light amount level at the time of zero calibration is set to a value obtained by adding a level difference corresponding to a light amount decrease in a full scale of a measurement range to a lower limit level of transmitted light that can be detected by a light receiving element. It is determined that the light amount falls below the set value as an abnormal decrease in the light amount.

In this case, in addition to the case where the measurement cannot be performed due to the burnout of the lamp and the case where the level of the transmitted light is reduced due to the contamination of the sample measurement cell and the measurement becomes impossible, the fact can be detected. Can be.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to FIGS. 1 to 4 by attaching the same reference numerals to the same members as those shown in FIG. .

In FIG. 1, a monitor light receiving element 12 for directly receiving a part of light 11 from the light source 2 is provided between the sample measuring cell 1 and the light source 2. A determination circuit 13 is connected to the output side of the monitoring light receiving element 12.

According to such a configuration, the light amount of the halogen lamp of the light source 2 is directly monitored by the monitoring light receiving element 12, and the determination circuit 13 determines whether or not the received light amount is less than the specified light amount. When the light amount falls below the specified light amount, it is determined that the lamp of the light source 2 has run out, and a necessary alarm is output. In this case, there is a possibility that the light intensity of the lamp may temporarily decrease.Therefore, it is necessary to repeat the operation of turning on and off the lamp as before, check whether the light intensity returns to the original value, and then turn off the lamp again. Confirm and issue an alarm.

Accordingly, regardless of the state of the sample water in the sample measuring cell 1 and the degree of contamination of the sample measuring cell 1,
The monitoring light receiving element 12 can detect only a decrease in the amount of light of the lamp of the light source 2 and can detect that the lamp has run out.

FIG. 2 shows another embodiment of the present invention.
Here, the monitoring light receiving element 12 is provided on the light receiving element 4 side with respect to the sample measurement cell 1. A part of the light from the light source 2 is guided to the monitor light receiving element 12 without passing through the sample measurement cell 1 by a light guide member 14 for bypass such as an optical fiber.

According to this, even though the monitoring light receiving element 12 is provided closer to the light receiving element 4 than the sample measuring cell 1, the monitor light receiving element 12 is not affected by the influx of turbid water into the sample measuring cell 1. Light for determining whether the lamp has run out can be guided to the light receiving element 12.

FIG. 3 shows still another embodiment of the present invention. Here, the light guide member 14 for bypass is guided to the light receiving element 4 without using the light receiving element for monitoring. Then, the light 3 transmitted through the sample measuring cell 1 and the light guide member 1 from the lamp of the light source 2 by a chopper or the like (not shown).
The light received by the light receiving element 4 is selectively switched between the direct light having passed through the light receiving element 4 and the light receiving element 4.

Therefore, in this case, normally, the turbidity and chromaticity of the sample are measured such that only the light 3 transmitted through the sample measuring cell 1 is received by the light receiving element 4, and when the lamp has run out, The light receiving element 4 receives only the direct light passing through the light guide member 14. In such a case, the light receiving element 4 and the detection circuit 5 can be used for both the original measurement purpose and the lamp burnout detection / judgment purpose without providing a special monitor light receiving element. it can.

As described above, in addition to the fact that the measurement cannot be performed due to the burnout of the lamp, the measurement may not be possible even if the sample measurement cell is contaminated and the level of transmitted light is reduced. When such a decrease in the level of transmitted light occurs, it is detected as follows and an alarm is issued.

That is, in FIG. 4, the vertical axis indicates the detection level of transmitted light in the light receiving circuit constituted by the light receiving element 4 and the detecting circuit 5. Numeral 16 denotes a lower detection limit level. When the level of transmitted light is lower than this, the sample can no longer be measured. Reference numeral 17 denotes a light level at the time of zero water flow, which indicates a light level at the time of zero calibration of the sample measuring cell 1 which is periodically performed. Light level 1 when this water flow is zero
Numeral 7 causes fluctuation as shown in the figure based on contamination of the sample measuring cell 1 and other causes. When a sample such as muddy water enters the sample measurement cell 1, the level of the detected light quantity is lower than the light quantity level 17 at zero water flow,
Numeral 18 indicates a decrease in the amount of light at the full scale of the measurement range.

Therefore, (lower detection level 1 in the light receiving circuit)
6) + (Level difference corresponding to light quantity decrease 18 at full scale) is set value 19. That is, when the light level 17 at the time of zero water flow during the zero calibration is lower than the set value 19, the detection level becomes lower than the detection lower limit 1 at full scale.
6, which makes it impossible to accurately measure the sample water within the measurement range. Therefore, it is determined that the light amount has dropped abnormally, and an alarm to that effect is issued.

[0024]

As described above, according to the present invention, a monitoring light receiving element for monitoring the amount of light of a lamp of a light source, and a determination circuit for determining whether the lamp of the light source has run out based on a signal from the monitoring light receiving element. The monitor light-receiving element can detect purely a decrease in the light intensity of the lamp of the light source, regardless of the state of the sample water in the sample measurement cell or the degree of contamination of the sample measurement cell, and the lamp burns out accurately. Can be detected.

Further, according to the present invention, means for guiding the monitoring light from the light source to the light receiving element by bypassing the sample measurement cell, the sample measurement light passing through the sample measurement cell and the bypassed monitor Means for selectively receiving light for use by the light receiving element, and a circuit for determining whether the lamp of the light source has run out based on a signal from the light receiving element when the light receiving element receives light for monitoring. Therefore, the detection and determination of lamp burnout can be performed only by the original light receiving element without specially providing the monitoring light receiving element as described above.

Further, according to the present invention, a value obtained by adding a level difference corresponding to a decrease in the amount of light in the full scale of the measurement range to the lower limit level of the transmitted light that can be detected by the light receiving element is set as a set value, When the detected light amount level falls below this set value, it is determined that the light amount is abnormally decreased.
In addition to the case where the measurement cannot be performed due to the lamp running out,
Even when the level of the transmitted light decreases due to contamination of the sample measurement cell and the measurement becomes impossible, the fact can be detected.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a lamp burnout detecting device of a colorimetric analyzer according to an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a lamp burnout detecting device of a colorimetric analyzer according to another embodiment of the present invention.

FIG. 3 is a diagram showing a schematic configuration of a lamp burnout detecting device of a colorimetric analyzer according to still another embodiment of the present invention.

FIG. 4 is a diagram illustrating the principle of detecting that the level of transmitted light has decreased due to contamination of the sample measurement cell according to the present invention.

FIG. 5 is a diagram showing a schematic configuration of a conventional colorimetric analyzer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sample measuring cell 2 Light source 4 Light receiving element 5 Detection circuit 12 Light receiving element for monitoring 13 Judgment circuit 14 Light guide member

Claims (4)

[Claims] A turbidity or chromaticity of a sample is determined based on an absorbance of the sample obtained by transmitting light from a light source to a sample measuring cell having a transmission window and detecting the transmitted light with a light receiving element. In a colorimetric analyzer configured to measure, a light receiving element for monitoring the amount of light of a lamp of the light source is provided, and a determination circuit for determining whether the lamp of the light source has run out based on a signal from the light receiving element for monitoring is provided. A lamp burnout detecting device for a colorimetric analyzer, characterized in that: 2. A monitor light-receiving element is provided closer to the light-receiving element than the sample measurement cell, and means for guiding monitor light from a light source to the monitor light-receiving element bypassing the sample measurement cell is provided. The lamp burnout detecting device of the colorimetric analyzer according to claim 1, wherein the lamp is burned. 3. The turbidity or chromaticity of a sample is determined based on the absorbance of the sample obtained by transmitting light from a light source to a sample measuring cell having a transmission window and detecting the transmitted light with a light receiving element. In the colorimetric analyzer configured to perform measurement, a unit that guides monitoring light from a light source to the light receiving element by bypassing the sample measurement cell; and a sample measurement light that has passed through the sample measurement cell and the bypass. Means for selectively receiving the monitored light by the light receiving element, and determining whether the lamp of the light source has run out based on a signal from the light receiving element when the light receiving element receives the monitoring light. And a circuit for detecting a lamp expiration of the colorimetric analyzer. 4. The turbidity and chromaticity of a sample are measured based on the absorbance of the sample obtained by transmitting light from a light source to a sample measuring cell having a transmission window and detecting the transmitted light with a light receiving element. In the colorimetric analyzer to be measured, the lower limit level of transmitted light that can be detected by the light receiving element,
Using the value obtained by adding the level difference corresponding to the decrease in light intensity at the full scale of the measurement range as the set value, if the detected light intensity level during zero calibration falls below this set value, it is determined that the light intensity is abnormally decreased. Characteristic method for detecting a decrease in light amount of a colorimetric analyzer.