JP2001289697A - Sample metering method using translucent container and sample injection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sample metering method in which a sample in a measuring flask can be metered at nearly the same reference as in a visual operation. SOLUTION: The sample metering method comprises an imaging process in which a prescribed range including the level 7 of the sample 6 is imaged in nearly the horizontal direction from the outside of the measuring flask 5. The method comprises a level detection process in which the position of the level 7 of the sample 6 is detected in such a way that an imaged image is scanned toward the movement direction of the level. The method comprises a metering process in which the sample is metered by comparing the position of the level with a reference position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sample weighing method and a sample injection apparatus using a translucent container suitable for automatic analysis or automatic test performed in, for example, the field of pharmaceutical and food production.

[0002]

2. Description of the Related Art In recent years, in the field of pharmaceutical and food production, stricter national safety standards have required more detailed quality control. To meet this demand, pharmaceutical and food manufacturers have the need to test more products with more different test or analytical methods. For this reason, there is a strong demand for an automatic test / analyzer capable of performing various tests or analyzes unattended and at high speed.

[0003] One of the operations common to all the tests or analyzes is an operation for measuring a sample using a measuring flask, that is, a so-called "measing-up detecting operation". Since this operation is originally based on visual judgment, it is difficult to automate only the weighing operation, even if the analysis and test itself can be automated. For this reason, each pharmaceutical and food manufacturer
We employ human naval tactics such as hiring a number of part-time workers to respond to the increase in experiments or analysis.

[0004]

As described above, since the weighing operation of a sample using a volumetric flask is based on visual judgment, it has been difficult in some cases to automate the operation.

The present invention has been made in view of such circumstances, and has been made in consideration of the above circumstances, and provides a sample weighing method capable of measuring a sample in a volumetric flask on substantially the same basis as that performed visually, and a sample using the weighing method. It is intended to provide an injection device.

[0006]

According to a first main aspect of the present invention, there is provided a sample weighing method for weighing a liquid sample placed in a light-transmitting container. An imaging step of imaging a predetermined range including the liquid level of the sample in a substantially horizontal direction from the outside of the translucent container,
A liquid level detection step of detecting the liquid level position of the sample by scanning the captured image in the liquid level rising direction,
A sample weighing method is provided, comprising a weighing step of weighing the sample by comparing the liquid level position with a reference position.

According to such a configuration, even when the edge of the liquid surface rises due to surface tension, the scanning direction is set to a predetermined direction, so that the liquid surface to be measured can be accurately detected. be able to. In addition, since the measurement is performed based on the distance between the liquid surface and the reference value, the reliability of the measurement is improved as compared with the case where the measurement is performed visually.

According to one embodiment, the weighing step comprises:
The liquid level of the sample and the reference position are identified by the color of the image, and the distance between them is measured. Here, the image may be composed of either a chromatic color or an achromatic color, and at least the liquid level of the sample and the reference position are determined by the brightness of the image (by binarization using a threshold value). (Including the shape of the liquid surface of the sample or the shape of the reference position)
It is desirable to identify the distance and measure the distance between them. More preferably, in the imaging step, it is preferable that the liquid surface of the sample and the reference position are imaged with a color image.

According to such a configuration, as compared with the case of performing detection using a simple binary image such as a projection image,
The liquid level and the reference position can be more clearly distinguished.

According to one embodiment, the measuring step comprises:
The distance between the liquid surface and the reference position is measured, and the distance is compared with a preset value to measure the sample.

According to such a configuration, for example, when the liquid is injected, by setting the set value to the position where the injection of the liquid is stopped, the injection can always be stopped by the same amount.

According to one embodiment, the weighing step comprises:
At the end of the measurement, a step of storing the distance between the liquid surface and the reference position as data is provided.

According to such a configuration, since the measurement result of the liquid can be left as objective data, it can be used to analyze the performance of the liquid injection device, for example.

According to one embodiment, the imaging step includes:
In the dark room or in an environment where light from the outside is constant, the predetermined range is imaged while illuminating the translucent container with diffuse illumination.

According to such a configuration, since the shadow of the liquid surface or the reference position is unlikely to occur, accurate detection can be performed.

According to a second main aspect of the present invention, there is provided a sample injection device for injecting a liquid sample into a light-transmitting container, the light-transmitting container holding means for holding the light-transmitting container, Sample injecting means for injecting a liquid sample into the translucent container, imaging means for imaging a predetermined range including the liquid level of the sample in a substantially horizontal direction from outside of the translucent container, and imaging by the imaging means Liquid level detecting means for detecting the liquid level position of the sample by scanning the image thus obtained in the upward direction of the liquid level,
A sample weighing means for comparing the liquid level position with a reference position, and stopping the sample injection by the sample injection means based on a difference between the liquid level position and the reference position becoming a predetermined set value; And a sample injection device characterized by having the following.

According to this configuration, even when the edge of the liquid surface is raised due to surface tension, the liquid surface to be measured can be accurately detected by setting the scanning direction to the predetermined direction. be able to. In addition, since the measurement is performed based on the distance between the liquid surface and the reference value, the reliability of the measurement is improved as compared with the case where the measurement is performed visually. This allows
The injection of the sample can be stopped exactly at the desired height.

According to one embodiment, the imaging means comprises:
The liquid level of the sample and the reference position are imaged with a color image, and the measuring means identifies the liquid level of the sample and the reference position by their colors and measures the distance therebetween. is there.

According to such a configuration, as compared with the case where detection is performed using a monochrome binary image such as a projection image,
The liquid level and the reference position can be more clearly distinguished.

According to one embodiment, the measuring means comprises:
A means for storing a distance between the liquid surface and a reference position as data when the sample injection by the sample injection means is stopped.

According to such a configuration, since the measurement result of the liquid can be left as objective data, it can be used to analyze and improve the performance of the injection device, for example.

According to one embodiment, the apparatus further comprises a casing for maintaining an imaging environment of the imaging means in a dark room or an environment in which light from outside is constant.
And a diffuse illumination means for illuminating the translucent container. Here, it is preferable that an insertion hole for inserting the sample injection means into the casing is formed in the casing.

According to such a configuration, since the shadow of the liquid surface or the reference position is unlikely to occur, accurate detection can be performed.

The other features and remarkable effects of the present invention will be more clearly understood from the following embodiments of the present invention and the accompanying drawings.

[0025]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a sample dispensing apparatus 1 (sample injecting apparatus) for carrying out the sample injecting method of the present invention. This sample dispensing apparatus 1 dispenses a sample 6 using an imaging camera shown in FIG. 4 when dispensing the sample 6 into the measuring cylinder 5 installed in the casing 2 using the injection nozzle 3. By monitoring the surface, dispensing by the injection nozzle 3 is accurately stopped at a predetermined liquid level (measuring height). Hereinafter, the configuration of this device will be described in detail.

The apparatus comprises a casing 2 for keeping the environment of the image taken by the imaging camera 4 in a dark room state, a graduated cylinder holder 8 installed in the casing 2 for holding the graduated cylinder 5, A camera holder 9 for holding the camera cylinder at a predetermined height and the imaging line substantially horizontal, and a ring illumination 11 (diffuse illumination) for uniformly illuminating the graduated cylinder 5.

On the upper surface of the casing 2, there are provided an opening 13 for taking the measuring cylinder 5 in and out of the casing 2, and an opening / closing door 14 which is slid to open and close the opening 13. . Above this opening 13, a hand mechanism 15 for holding the graduated cylinder 5 and the injection nozzle 3 are arranged so as to be able to selectively face each other, and are inserted into the casing 2. In addition, an insertion hole 17 for inserting the tip of the injection nozzle 3 into the casing 2 is formed at the center of the opening / closing door 14.

A black reference line 18 is drawn on the measuring cylinder 5 at a height at which the dispensing of the sample is to be stopped, for example, with a chemical resistant paint. The relative height of the measuring cylinder 5 and the imaging camera 4 is adjusted so that the reference line 18 is located substantially at the center along the height direction of the image captured by the camera. For this reason, it is preferable that the camera holder 9 or the graduated cylinder holder 8 is configured to be adjustable in height. Further, the imaging camera 4 is held upside down in order to adapt the scanning direction of the captured image to the present invention.

The imaging camera 4 is connected to a control device indicated by reference numeral 20 in FIG. 1 so that an image of the sampled image is analyzed. Further, a hand drive mechanism 23 for driving the hand mechanism 15, a discharge control mechanism 24 for controlling driving / discharge of the injection nozzle 3, and the ring illumination 11.
Is also connected to the control device 20, and is controlled by the control device 20.

FIG. 2 is a functional block diagram for explaining the control by the control device 20.

The control device 20 includes a monitor device 30 for displaying an image picked up by the image pickup camera 4 and a liquid level detecting unit 31 for detecting the liquid level 7 of the sample 6 by scanning the picked-up image. And the detected liquid level 7 and the reference line 1
8 based on the fact that the distance between the liquid level 7 and the reference line 18 has become equal to or less than the mess-up reference value taken out of the mess-up reference value storage section indicated by 34 in FIG. The apparatus includes an ejection stop unit 35 for stopping the ejection of the sample by the ejection control mechanism 24, and a weighing data storage unit 36 for storing the distance between the liquid level and the reference position when the ejection of the sample is stopped as weighing data.

Here, the imaging camera 4 outputs a color image, and the liquid level detecting section 31 is configured to identify the liquid level 7 of the sample 6 from the reference line by its color. Have been. Further, since the imaging camera 4 is held upside down, the image 29 displayed on the monitor device 30 is upside down as shown in FIG. Then, when this is processed by the liquid level detection unit 31, the pixel is scanned from right to left starting from the upper left corner 40 as usual, and each time it is incremented by one pixel from top to bottom. To go. Thus, the liquid level 7 can be detected when the color changes.

Generally, in the case of a liquid sample, a phenomenon occurs in which the peripheral portion (the portion indicated by A in FIG. 3) rises above the liquid surface to be measured due to surface tension. For this reason, if you scan from top to bottom along the vertical direction like normal image processing,
This peripheral portion where the color changes for the first time is erroneously detected as the liquid level. However, according to the method of this embodiment, the liquid surface 7 to be measured can be accurately detected by scanning from the bottom to the top along the vertical direction.

Next, the liquid level detector 31 detects a reference height based on the color of the reference line 18. If the liquid level 7 and the reference line 18 are detected by the liquid level detection unit 31,
This data is sent to the comparison unit 32. This comparison unit 3
2 obtains the distance between the liquid level 7 and the reference line 18 and compares the distance with the mess-up reference value stored in the mess-up reference value storage section 34. If the distance is larger than this value, the scanning, Repeat detection and comparison.

As a result, when the distance between the liquid surface 7 and the reference line 18 becomes equal to or less than the mess-up reference value, the discharge stop unit 35 gives a command to the discharge control mechanism 24 to Stop discharging the sample. Further, the distance between the liquid surface 7 and the reference line 18 at this time is stored in the measurement data storage unit 36 as measurement data.

When the detection is performed, the graduated cylinder 5 is set in the casing 2 by the hand mechanism 15, and then the opening / closing door 14 of the casing 2 is closed. Then, the tip of the injection nozzle 3 is inserted into the casing 2 through an insertion hole 17 provided at the center of the opening / closing door 14 to start injection of the sample. Then, when taking an image with the imaging camera 4, the ring illumination 11 is operated. Since this imaging is performed in a dark room and is illuminated with diffused light, the liquid surface 7 and the reference line 18 can be imaged in a good state without shadows.

According to the configuration described above, the following effects can be obtained.

First, even when the edge of the sample liquid surface rises due to surface tension, the liquid surface to be measured can be accurately detected by setting the scanning direction to a predetermined direction. . In addition, since the measurement is performed based on the distance between the liquid surface and the reference value, the reliability of the measurement is improved as compared with the case where the measurement is performed visually. This makes it possible to stop the injection of the sample accurately at the desired height.

Further, according to such a configuration, accurate weighing can be performed without using an expensive imaging unit and driver having a special scanning function.

Therefore, according to the above configuration, a sample weighing method capable of automatically weighing a sample in a translucent container with a simple configuration on substantially the same basis as that performed visually, and a sample using this weighing method An injection device can be provided.

Second, since the imaging camera 4 is of a color type, the liquid level and the reference position can be more clearly defined as compared with the case where detection is performed using a monochrome binary image such as a projected image. Can be distinguished.

Third, when injecting a predetermined amount of liquid sample, it is possible to digitally set a specific set-up reference value instead of making a visual judgment as in the conventional case. This improves the reliability of the device.

Fourth, since the measurement result of the sample is left as objective measurement data, the performance of the sample injection device can be analyzed and fed back using the objective measurement data.

The present invention is not limited to the above-described embodiment, but can be variously modified without changing the gist of the invention.

For example, in the above-described embodiment, the imaging by the imaging camera is performed in a casing capable of creating a dark room state.
There is no need to image in a dark room condition.

In the above embodiment, the imaging camera 4 is a color camera. However, if the liquid level and the reference position can be clearly distinguished, for example, a gray scale image may be used. . That is, the image may be composed of any of a chromatic color and an achromatic color, and at least, the liquid level of the sample and the reference position are identified by the brightness of the image, and the distance between them is measured. Desirably. In addition, the above image is expressed as 2
The value may be converted into a value, and the shape of the liquid surface of the sample may be determined for determination.

[0048]

As described above, the present invention provides a sample weighing method capable of automatically weighing a sample in a light-transmitting container on substantially the same basis as that performed visually, and a sample injection device using this weighing method. can do.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a sample injection device according to an embodiment of the present invention.

FIG. 2 is a functional block diagram for explaining a control device.

FIG. 3 is a diagram for explaining an image scanning method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Sample dispensing apparatus 2 ... Casing 3 ... Injection nozzle 4 ... Imaging camera 5 ... Measuring cylinder 6 ... Sample 7 ... Liquid level 8 ... Measuring cylinder holding stand 9 ... Camera holding stand 11 ... Ring illumination 13 ... Opening 14 ... Opening / closing door Reference numeral 15: Hand mechanism 17: Insertion hole 18: Reference line 20: Control device 21: Hand drive mechanism 24: Discharge control mechanism 29: Image 30: Monitor device 31: Liquid level detection unit 32: Comparison unit 34: Storing the female up reference value Unit 35: Discharge stop unit 36: Measurement data storage unit 40: Upper left corner

Claims (14)

[Claims] 1. A sample weighing method for measuring a liquid sample to be put into a translucent container, wherein a predetermined range including a liquid level of the sample is substantially horizontal from outside of the translucent container. A liquid level detecting step of detecting the liquid level position of the sample by scanning the captured image in the rising direction of the liquid level, and determining the liquid level position and the reference position. And a weighing step of weighing the sample by comparing. 2. The sample weighing method according to claim 1, wherein the weighing step identifies a liquid level of the sample and the reference position by a color of an image and measures a distance therebetween. Sample weighing method. 3. The sample weighing method according to claim 2, wherein the weighing step is to identify a liquid surface of the sample and the reference position by brightness of an image and measure a distance therebetween. Sample weighing method. 4. The sample weighing method according to claim 2, wherein the imaging step captures a color image of the liquid level of the sample and the reference position, and the weighing step includes a liquid level of the sample. And a reference position, which is distinguished by its color and measures a distance between the reference position and the reference position. 5. The sample measuring method according to claim 1, wherein in the measuring step, a distance between the liquid surface and the reference position is measured, and the distance is compared with a preset set value to thereby measure the sample. A sample weighing method characterized by performing weighing. 6. The sample measuring method according to claim 5, wherein the measuring step includes a step of storing a distance between the liquid surface and a reference position as data at the end of the measuring. Weighing method. 7. The sample weighing method according to claim 1, wherein in the imaging step, the predetermined range is illuminated with diffuse illumination in the dark room or in an environment where light from the outside is constant. A method for weighing a sample, characterized in that a sample is imaged. 8. A sample injection device for injecting a liquid sample into a translucent container, comprising: a translucent container holding means for holding the translucent container; and injecting the liquid sample into the translucent container. Sample injection means, imaging means for imaging a predetermined range including the liquid level of the sample in a substantially horizontal direction from the outside of the light-transmitting container, and an image taken by the imaging means in a direction in which the liquid level rises. Liquid level detecting means for detecting the liquid level position of the sample, and comparing the liquid level position with the reference position, and the difference between the liquid level position and the reference position becomes a predetermined set value. A sample measuring means for stopping the sample injection by the sample injection means based on the fact that the sample injection has been completed. 9. The sample injecting apparatus according to claim 8, wherein the measuring unit is configured to identify a liquid level of the sample and the reference position by a color thereof and measure a distance therebetween. Sample injection device. 10. The sample injecting apparatus according to claim 9, wherein the measuring unit is configured to identify a liquid level of the sample and the reference position by brightness of an image and measure a distance therebetween. Sample weighing method. 11. The sample injection device according to claim 9, wherein the imaging unit is configured to image a liquid surface of the sample and the reference position with a color image, and the measuring unit is configured to measure the liquid surface of the sample. And a reference position which is identified by its color and measures a distance between the reference position and the reference position. 12. The sample injection device according to claim 8, wherein the measuring means has a means for storing a distance between the liquid surface and a reference position as data when the sample injection by the sample injection means is stopped. A sample injection device, characterized in that: 13. The sample injection device according to claim 8, further comprising: a casing for maintaining an imaging environment of the imaging unit in a dark room or an environment where light from outside is constant; and illuminating the translucent container. And a diffused illumination means. 14. The sample injection device according to claim 13, wherein an insertion hole for inserting the sample injection means into the casing is formed in the casing.