JP2001050794A - Method and device for measuring liquid quantity, and dispenser provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device of noncontact type for measuring a a liquid quantity capable of measuring quickly a weight or volume of a liquid such as a serum specimen without using optical measurement complicated in adjustment, and to provide a dispenser with the device. SOLUTION: This liquid quantity measuring device is provided with a resonance circuit 2 having a coil freely inserted with a specimen container in its inside. A detection circuit 3 is provided to detect a resonance frequency changed by inserting the specimen container into the coil. An operation circuit 4 is further provided to calculate a liquid quantity based on the resonance frequency detected by the detection circuit 3. When the specimen container is inserted into the coil, an inductance of the coil is changed in response to the liquid quantity, and the resonance frequency is changed thereby. The detection circuit 3 detects the resonance frequency, and the operation circuit 4 calculates the liquid quantity based on the resonance frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid volume measuring method capable of automatically and highly accurately measuring the weight or volume of a blood sample or the like collected from a patient or the like when testing and analyzing the same. The present invention relates to a liquid amount measuring device and a dispensing device equipped with the liquid amount measuring device.

[0002]

2. Description of the Related Art As is well known, in the field of blood analysis for measuring the quantity of a specific substance, it is very important to obtain a certain amount of serum from collected blood in order to maintain high measurement accuracy. For this reason, at present, various types of aspirating liquid amount measuring devices for managing the amount of aspirated serum are provided in a dispensing device for automatically aliquoting a predetermined amount of serum.

As this conventional suction liquid amount measuring device, a contact type measuring device represented by an electrode method and a non-contact type measuring device such as a light reflection method and a light transmission method are known.

However, in the above-mentioned contact type measuring device, since the tip of the electrode is in contact with the serum sample, a washing device is indispensable in order to avoid cross-contamination. The whole had a fundamental problem that it was complicated, large, and high in cost.

In the case of a non-contact type measuring device using light, a cleaning device such as an optical fiber is not required, so that the device can be simplified, downsized, and reduced in cost.
There is a problem that it is difficult to reliably receive light reflection and light transmission, and the adjustment is very complicated.

The present invention has been made in view of the above circumstances, and has as its object to quickly adjust the weight or volume of a liquid such as a serum sample without using optical measurement which is complicated to adjust. It is an object of the present invention to provide a non-contact type liquid amount measuring method and a liquid amount measuring device which can be measured, and a dispensing device equipped with the liquid amount measuring device.

[0007]

According to one aspect of the present invention, there is provided a method for measuring an amount of a liquid injected into a container, comprising the steps of: The resonance frequency that changes when the container is placed in the coil that constitutes (i) is detected, and the amount of the liquid is calculated by an arithmetic circuit based on the changed resonance frequency.

When the amount of liquid in the container is measured by the liquid amount measuring method according to claim 1 configured as described above, the container into which the liquid is injected is connected to the inside of a coil constituting a resonance circuit. Insert When the container is inserted into the coil, the inductance of the coil changes according to the amount of liquid in the container, and the resonance frequency changes. Then, the arithmetic circuit calculates the amount of the liquid based on the changed resonance frequency. That is, since there is a correlation between the amount of liquid in the container and the resonance frequency, the amount of liquid can be calculated from the resonance frequency. The arithmetic circuit stores a program for calculating the amount of liquid corresponding to the resonance frequency value, and calculates the amount of liquid according to the program.
Further, the container is made of a material having an inner diameter or the like corresponding to the program and having a certain standard and made of a material that does not affect the inductance, such as a synthetic resin.

According to the first aspect of the present invention, since the apparatus is constructed and operates as described above, it is possible to measure the liquid amount quickly in a non-contact manner, and to easily realize the simplification, miniaturization and cost reduction of the apparatus. can do. In addition, since the shape of the container can be made arbitrary and the measurement can be performed even when the liquid is frozen, the applicable inspection range can be greatly expanded as compared with the conventional measurement method. In addition, since the measurement can be performed even when a label or the like (except for a metal one) is attached to the container, it is possible to reliably prevent an artificial mistake in mixing the sample due to the replacement of the label and the like. Can be measured even in a colored container, which was difficult or impossible with the conventional optical measurement method.

According to a second aspect of the present invention, a change in the temperature of the coil is detected together with the resonance frequency, and the amount of liquid calculated by the arithmetic circuit is corrected based on the detected coil temperature. It is characterized by obtaining a quantity. By adopting such a configuration,
In addition to the above-described functions and effects, a measurement error due to thermal expansion of the coil and the like can be corrected, so that the accuracy of the measured value is improved. In addition, as described in claim 3, the amount of the liquid can be at least one of the weight and the volume of the liquid.

According to the present invention, there is provided a liquid amount measuring device for realizing the above method, wherein the liquid amount measuring device for measuring the amount of liquid injected into the container is provided. A measurement device, a resonance circuit having a coil into which the container can be inserted, a detection circuit that detects a resonance frequency that is changed by inserting the container into the coil, and a detection circuit that is detected by the detection circuit. And an arithmetic circuit for calculating the amount of the liquid based on the resonance frequency.

When the amount of liquid in the container is measured by the liquid amount measuring apparatus according to claim 4 configured as described above, the container into which the liquid is injected is connected to the inside of a coil constituting a resonance circuit. Insert When the container is inserted into the coil, the inductance of the coil changes according to the amount of liquid in the container, and the resonance frequency changes. The detection circuit detects the changed resonance frequency and sends it to the arithmetic circuit. Then, the arithmetic circuit calculates the amount of the liquid based on the changed resonance frequency. That is, since there is a correlation between the amount of liquid in the container and the resonance frequency, the amount of liquid can be calculated from the resonance frequency. The arithmetic circuit stores a program for calculating the amount of liquid corresponding to the resonance frequency value, and calculates the amount according to the program. Further, the container is made of a material having an inner diameter or the like corresponding to the program and having a certain standard and made of a material that does not affect the inductance, such as a synthetic resin.

According to the fourth aspect of the present invention, since the apparatus is constructed and operates as described above, it is possible to rapidly measure the liquid amount in a non-contact manner, and to easily realize the simplification, miniaturization and cost reduction of the apparatus. can do. In addition, the shape of the container can be made arbitrary, and the measurement can be performed even when the liquid is frozen, so that the inspection can be facilitated. In addition, since the measurement can be performed even if a label or the like (excluding a metal-made one) is attached to the container, it is possible to reliably prevent a mistake in artificially mixing samples due to label replacement or the like. The amount of liquid in the colored container can also be measured.

Further, in the invention described in claim 5, a temperature detector for detecting the temperature of the coil is provided, and the arithmetic circuit is configured to detect the temperature of the coil based on the temperature of the coil detected by the temperature detector. The liquid amount calculated based on the resonance frequency is corrected to a true value.
By adopting such a configuration, the above-described operation and
In addition to the effect, the accuracy of the measured values is improved.

Further, as described in claim 6, it is also possible to provide an output device capable of outputting the amount of liquid calculated by the arithmetic circuit. The output device may be a printing device or a display device. With such a configuration, the measured value can be easily recognized, and the measured value can be applied to other purposes. Claim 7
As described in the above, the amount of the liquid can be at least one of the weight and the volume of the liquid.

The liquid amount measuring method and the liquid amount measuring device configured as described above are arranged in the dispensing device as described in claim 8, so that the measuring accuracy is higher than that of the conventional dispensing device. The dispensing apparatus itself can be easily improved, and of course, the dispensing apparatus itself can be simplified, reduced in size and reduced in cost, and the liquid amount in the pipette tip can be measured without contact.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail based on an embodiment shown in the accompanying drawings.

As shown in FIG. 1, in the liquid amount measuring apparatus according to this embodiment, a sample container 1 (see FIG. 2) into which a liquid sample R such as blood (hereinafter, simply referred to as liquid R) is inserted. A resonance circuit 2 having a flexible coil L; a detection circuit 3 for detecting a resonance frequency that changes according to the amount of liquid R in the sample container 1 by inserting the container 1 into the coil L; And an arithmetic circuit 4 for calculating the amount of the liquid based on the resonance frequency detected by the circuit 3. The amount of the liquid is at least one of the weight and the volume of the liquid.

As shown in FIG. 2, the resonance circuit 2 is configured by connecting a coil L and a capacitor C in parallel. The coil 4 has such an inside diameter that the sample container 1 can be inserted. The length of the coil L is
The length is set so that the liquid level of the liquid R to be injected into the coil L is positioned in the coil L.

The detection circuit 3 comprises a so-called digital counter, and converts the resonance frequency generated by the resonance circuit 2 into digital data.

The arithmetic circuit 4 comprises a one-chip microcomputer (CPU, MPU) and the like. In this embodiment, the arithmetic circuit 4 has a function of calculating a liquid amount conversion curve, a function of calculating a liquid amount, and a temperature correction processing function described later. These functions are performed based on a program stored in a storage unit such as a ROM (Read Only Memory) attached to the arithmetic circuit 4.

Further, in this embodiment, a temperature sensor 5 which is a temperature detecting section for detecting the temperature of the coil L is provided. As the temperature sensor 5, various conventionally known temperature sensors can be adopted. The temperature detected by the temperature sensor 5 is sent to the arithmetic circuit 4, and is used by the arithmetic circuit 4 to correct the weight or volume calculated based on the resonance frequency. For this reason, the arithmetic circuit 4 is also provided with a function of performing such a temperature correction.

In this embodiment, a display 6 for displaying the amount of the liquid R calculated by the arithmetic circuit 4 is provided. This display 6 corresponds to the output device described in the claims. In addition, as the output device, a printer that records the above amount, a voice display device that shows the above amount by voice, and the like can be considered. Further, the arithmetic circuit 4 transmits the calculated amount to an external device, and is configured to be able to output the external amount so that the external device can use the calculated amount.

The sample container 1 is of a certain standard having an inner diameter or the like corresponding to the above program, and is made of a material such as a synthetic resin which does not affect the inductance. The data such as the inner diameter is calculated by the arithmetic circuit 4
In the storage unit. Then, a calculation formula for calculating the amount of the liquid R based on these specifications is incorporated in the program. In the program, a relational expression between the measured resonance frequency and the liquid R in the sample container 1 is incorporated in advance. In this embodiment, a logistic curve of the resonance frequency and the amount of the liquid R is stored, and a conversion formula is calculated using the logistic curve.
This is the above-described liquid volume conversion curve calculation function. further,
The actual amount of the liquid R is calculated by this conversion formula. This function is the above-described liquid amount calculation function. Of course, you may calculate using another well-known conversion formula.

When the amount of the liquid R in the sample container 1 is measured based on the liquid amount measuring method according to the present invention using the liquid amount measuring device according to this embodiment configured as described above, Do so. First, the sample container 1 into which the liquid R is injected is inserted into the coil L constituting the resonance circuit 2. When the sample container 1 is inserted into the coil L, the inductance of the coil L changes according to the amount of the liquid R in the sample container 1, and the resonance frequency F (= 1 / 2π√ (L ·
C) where L is inductance and C is capacitance. ) Changes. The detected resonance frequency is detected by the detection circuit 3, converted into digital data, and sent to the arithmetic circuit 4.

Then, the arithmetic circuit 4 calculates the amount of the liquid R by the liquid amount conversion curve calculating function and the liquid amount calculating function based on the changed resonance frequency. Further, in this embodiment, a temperature sensor 5 for detecting the temperature of the coil L is provided, and the arithmetic circuit 4 calculates the resonance frequency based on the temperature of the liquid detected by the temperature sensor 5. Correct the amount of liquid to make it a true value. That is, since the state of the coil L changes in density and the like depending on the heat generation temperature, the calculated amount of the liquid R is slightly different. Therefore, the temperature is detected by the temperature sensor 5 and the temperature is corrected by the temperature correction function. The amount of liquid obtained in this way is displayed on the display 7 and sent to another device via an external output terminal for use.

Since the liquid amount measuring device according to this embodiment is constructed and operates as described above, the liquid amount can be measured quickly in a non-contact manner, and the device can be easily simplified, miniaturized and reduced in cost. Can be realized. In addition, since the shape of the sample container 1 can be made arbitrary and measurement can be performed even when the liquid is frozen, the inspection can be facilitated. In addition, since the measurement can be performed even if a label or the like (excluding a metal-made one) is attached to the container, it is possible to reliably prevent a human mistake in mixing samples due to label replacement or the like.
Further, since the temperature is corrected, the accuracy of the measured value is improved. Furthermore, since the apparatus is provided with an output device such as the display 7, the measured value can be easily recognized, and the measured value can be applied to other purposes.

It should be noted that the liquid amount measuring device having the above configuration can be used not only alone but also attached to, for example, an automatic analyzer or a dispensing device. When measuring the amount of the liquid sample in the sample container 1 or in the pipette tip (not shown) using the measuring apparatus according to the present invention, the sample container 1 or the pipette tip may be inserted into the coil, If the liquid volume measuring device is provided at a predetermined position in an automatic analyzer or a dispensing device, and the sample container 1 is inserted into and removed from the coil by a three-dimensional driving device, the measurement of the sample amount can be automatically performed quickly. Can be done.

[0029]

The liquid amount measuring method and the liquid amount measuring device according to the present invention are constructed and operated as described above, so that the liquid amount can be measured quickly in a non-contact manner, and the apparatus can be simplified, downsized, and compact. Cost reduction can be easily realized. In addition, the shape of the container can be made arbitrary, and the measurement can be performed even when the liquid is frozen, so that the inspection can be facilitated. In addition, since the measurement can be performed even if a label or the like (excluding a metal-made one) is attached to the container, it is possible to reliably prevent a mistake in artificially mixing samples due to label replacement or the like. Even in a colored container, the liquid amount in the container can be reliably measured without contact.

Further, if the temperature is corrected, the accuracy of the measured value is improved. Furthermore, the configuration provided with the output device makes it possible to easily recognize the measured value and to apply the measured value to other applications, particularly when the method and the device are arranged in the dispensing device. Has many excellent effects, such as not only improving its practicality but also greatly expanding the applicable range of quantitative measurement.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a diagram for explaining a resonance circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 sample container 2 resonance circuit 3 detection circuit 4 arithmetic circuit 5 temperature sensor 6 display

Claims (8)

[Claims] 1. A liquid amount measuring method for measuring an amount of liquid injected into a container, the method comprising detecting a resonance frequency that changes when the container is inserted into a coil constituting a resonance circuit, and performing an arithmetic operation. A liquid amount measuring method, wherein a circuit calculates the amount of the liquid based on the changed resonance frequency. 2. The method according to claim 1, wherein a temperature change of the coil is detected together with the resonance frequency, and an amount of the liquid calculated by the arithmetic circuit is corrected based on the detected coil temperature to obtain an amount of the liquid. The method for measuring a liquid amount according to claim 1. 3. The method according to claim 1, wherein the amount of the liquid is at least one of a weight and a volume of the liquid. 4. A liquid amount measuring device for measuring the amount of liquid injected into a container, comprising: a resonance circuit having a coil in which the container can be inserted; and a resonance circuit including the coil in the coil. A liquid amount measurement device comprising: a detection circuit that detects a resonance frequency that changes by insertion; and an arithmetic circuit that calculates the amount of the liquid based on the resonance frequency detected by the detection circuit. 5. A temperature detecting unit for detecting a temperature change of the coil, wherein the arithmetic circuit calculates an amount of liquid calculated by the resonance frequency based on a temperature of the coil detected by the temperature detecting unit. The liquid amount measuring device according to claim 4, wherein the liquid amount is corrected and set to a true value. 6. The liquid amount measuring device according to claim 4, further comprising an output device capable of outputting the liquid amount calculated by the arithmetic circuit. 7. The liquid amount measuring device according to claim 4, wherein the amount of the liquid is at least one of a weight and a volume of the liquid. 8. The dispensing device according to claim 4, wherein the liquid amount measuring device measures a suction liquid amount in the dispensing device.