JPS60185134A - Apparatus for detecting remaining quantity of liquid - Google Patents

Abstract

PURPOSE:To make it possible to perform detection of the presence or absence of a liquid in a tank and computation of the remaining amount of the liquid readily, by detecting the initial liquid level, and counting the number of sucking of the specified amount by distributing nozzles. CONSTITUTION:A motor 4 is driven and a turret 5 is intermittently turned. A motor 15 is driven with respect to each tank 1, and a light projector 13 and a light receiver 14 are lifted and lowered. The initial liquid level is detected, and the amount of the encoder of the motor 15 is stored in a memory device 16. Drivers 17, 18 and 19 for the motors 4, 10, and 15 are connected to a control device 20. The decrease in amount of the liquid level due to the sucking of a liquid 2 by one time is stored in the control device 20. A counter 21 for counting the number of suction of the liquid is connected to the device 20. The device 20 computes the present liquid level of the liquid based on the initial liquid level of the device 16, the counted value of the counter 21 and the amount of decrease in liquid level due to sucking, and the remaining amount of the liquid in the tank can be found.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a remaining liquid amount detection device suitable for use in a biochemical analyzer, and in particular a remaining liquid amount detection device for detecting the remaining amount of liquid such as a sample or reagent to be aspirated. This invention relates to a detection device.

(Prior art) For example, as a device for dispensing only serum from serum and blood cells separated by a centrifuge, etc., there is a serum fractionating device disclosed in Japanese Patent Application Laid-open Nos. 53-39184 and 53-39185. be. In the former sorting device, two electrodes are inserted into a container containing centrifuged serum and blood cells together with a nozzle, and the amount of penetration into the nozzle is controlled by measuring the change in electrical resistance between the electrodes. This is what I did. In the latter sorting device, optical fibers for transmitting and receiving light are lowered together with a nozzle, and the amount of reflected light received is measured to control the amount of penetration of the nozzle. That is,
These sorting devices detect the interface between serum and blood cells and position the nozzle above this interface to aspirate only the serum. If these preparative separation devices are designed to detect the interface between the serum and the outside air, that is, the liquid level, they can be configured so that the nozzle injects a predetermined amount into the liquid depending on the liquid level. It is possible to dispense predetermined amounts of samples such as serum only, blood cells only, blood or urine without centrifugation, or samples necessary for analysis of these samples.

However, after a liquid such as a reagent is aspirated multiple times from a tank containing a liquid such as a reagent using a preparative separation device configured in this manner, it is not possible to know how much reagent remains. In particular, with the dispenser of an automated analyzer, if the only dispensing operation is to detect the presence of liquid by detecting the liquid level, even if the amount inhaled is less than the predetermined amount, the insufficient amount of reagent will prevent the next operation. However, there was a drawback that it greatly affected the analysis results.

(Object of the Invention) The object of the present invention is to eliminate the above-mentioned drawbacks and to provide a suitably constructed liquid remaining amount detection device that not only detects the presence or absence of liquid but also determines the amount of adults remaining in the tank. be.

(Summary of the Invention) A liquid remaining amount detection device of the present invention includes a liquid level detection device that detects the liquid level of a liquid contained in a tank, and a liquid level detection device that detects a liquid level of a liquid contained in a tank. It is characterized by comprising a dispensing nozzle that sucks and discharges, a dispensing nozzle lifting device that allows the dispensing nozzle to enter, and a control device that calculates the remaining amount of liquid in the tank based on the liquid level. It is something to do.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of an example of the dispensing device of the present invention. In this example, a common dispensing nozzle 3 is selectively inserted into a predetermined amount of various liquids 2 stored in several translucent tanks 1 to dispense a predetermined amount of the combined liquid. This is how it was done. Several tanks 1 are arranged on the same circumference on a turret 5 fixed to the rotating shaft of a motor 4. Further, an encoder 6 is attached to the rotating shaft of the motor 4 for reading the tank, that is, the type of liquid to be aspirated, when the dispensing nozzle 3 is lowered.

The dispensing nozzle 3 is held on the arm 7 and connected to the syringe 8 via a suitable tube. The arm 7 is moved to a suction position (not shown) and a discharge position (not shown) by a rotating mechanism (not shown)! ! The dispensing nozzle lift device is configured to raise and lower the dispensing nozzle 3 from the co-suction position. A rack 9 is formed, and a pinion gear 1 fixed to the rotating shaft of the motor 1o is mounted on this rack.
1 mesh to form lfl.

Further, an initial liquid level detection device is provided across the rotation path of the tank 1 to detect the initial liquid level of the liquid stored in each tank.

In this device, a light projector 13J5 and a light receiver 14 for detecting the initial liquid level are installed facing each other so that the tank 1 is sandwiched between the holding frame 12), and the holding frame 12 can be raised and lowered by a motor 15, and The initial liquid level is stored in the storage device 16.

Furthermore, the motors 4, 10 and 15 are each connected to a driver 1.
The control device 20 is installed via 7.18.19. This control device 2o is connected with a counter 21 that stores in advance the decrease in the liquid level due to one suction of the combined liquid 2, and counts the number of suctions of the combined liquid.
Regarding the liquid to be sucked, the initial liquid level of the liquid stored in the storage device 16, the count value of the counter 21 for the liquid ('?j, the number of times the liquid has already been sucked), !
3 and the pre-stored amount by which the level of the liquid drops during one suction of the liquid, the current level of the liquid is calculated, and the remaining amount of the liquid in the tank is determined. Also, in accordance with this, the driver 18
Through these steps, the rotation of the motor 1o is controlled so that the dispensing nozzle 3 always enters a predetermined amount of the liquid to be sucked. The control device 20 also generates an alarm signal when the current liquid level (residual amount) of the liquid to be sucked falls below a predetermined level, for example, below the amount of suction twice. This signal drives an alarm device 22 such as a lamp or a buzzer. This control device 20 is further connected to a keychain 23 for inputting signals for sequentially moving the tank 1 containing a predetermined liquid 2 to the suction position.

Next, the operation of the dispensing device shown in FIG. 1 will be explained.

First, before performing a dispensing operation on the combined liquid, the initial liquid level of the combined liquid is stored in the storage device 6 by the initial liquid level detection device. This is done by intermittently rotating the turrets 1-5 driven by the motor 4, and for each tank 1,
The motor 15 is driven to move the emitter 13 and the receiver 14 up and down via the holding frame 12, and the position where the amount of received light changes (i.e., the interface between the liquid 2 and the outside air) is detected, and a signal corresponding to this is detected. That is, the encoder value of the motor 15 is stored in the storage device 16. In this way, after detecting the initial liquid level of the combined liquid 2, the liquid 2 contained in the desired tank 1 is dispensed by the dispensing nozzle 3 according to the command from the control wave @20 based on the input signal from the keyboard 23. Note.

Here, the distance from the lower surface of the inner wall of each tank 1 to the top dead center position of the dispensing nozzle 3 (solid line position in the figure) is H1, the amount of penetration of the dispensing nozzle into the liquid for each liquid 2 is S, and the storage device 1
The initial liquid level of the combined liquid 2 in each tank 1 stored in 6 is set to 1, 112, ..., n0, and the amount by which the liquid level drops after 11 suction operations is set to 1, k2 for each tank 1. ,...
・kn (tank cross-sectional area constant), dispensing (suction) as shown
A case will be described in which a predetermined amount of liquid 2 is sucked from the n-th tank 1 at the position. The amount of descent of the dispensing nozzle 3 for the first suction operation for this tank 1 is ()-1
-hr++3>, the amount of descent of the dispensing nozzle during the N-th suction is the count value of the counter 21, that is, the number of times the n-th tank 1 has already been suctioned is (N-1>
Therefore, if (H-hn+3-1-(N-IN<n)), the dispensing nozzle 3 always enters the liquid by a certain amount fiS.

That is, by calculating the above equation using the control wave @20 and rotating the motor 10 for lifting and lowering the dispensing nozzle according to the calculated amount, the dispensing nozzle 3 can be made to penetrate into the liquid by a certain distance S. . Also, (H-1111+8+
When the value of (N - 1) Kn) becomes larger than a certain value, that is, when the current liquid level becomes smaller than a certain value, an alarm signal is generated to trigger the alarm device 22! I.J.
By g, the remaining amount alarm can be easily issued.

According to the above-mentioned dispensing device, since no electrode or the like is inserted into the liquid, contamination between the liquids due to the electrode or the like can be effectively prevented.

Furthermore, the amount of penetration of the dispensing nozzle into the liquid is determined mechanically, regardless of the type or temperature of the liquid, so it is reliable. Based on the detection of the liquid level, the remaining amount of liquid in the tank can be easily determined.

Furthermore, after detecting the initial liquid level, it is only necessary to lower the dispensing nozzle 3 by the amount calculated by the control wave @20, so the dispensing time can be shortened. .

FIG. 2 is a perspective view diagrammatically showing the configuration of essential parts of a biochemical analyzer using the dispensing device of the present invention as a reagent dispensing device. Since this dispensing device has almost the same configuration as the dispensing device shown in FIG. 1, the same reference numerals indicate the same members, but several tanks 1 contain various reagents necessary for sample analysis.

In addition, in order to rotate the dispensing nozzle 3 together with the arm 7 and move it to the reagent suction position (indicated by a solid line) and the dispensing position (indicated by a phantom line), a rack 9 for lifting and lowering is formed and extends in the vertical direction. Attach the thrust bearing 25 to the member that
A belt 27 is wound between this bearing and the output shaft of a rotating motor 26, and the belt 27 is driven by the motor 26.
7, the arm 7 and the dispensing nozzle 3 are rotated to predetermined suction and discharge positions.

The biochemical analyzer shown in this example holds a plurality of sample tubes 30 containing several types of samples in a sample turret 31, and rotates the tube intermittently in the direction of the arrow. The sample in each sample tube 30 is sequentially dispensed by a sample dispensing device 32 into a reaction tube 34 that is transferred along a predetermined reaction line 33 in the direction of arrow 8 . At the reagent discharge position, a reagent necessary for analyzing the sample is dispensed into the reaction tube 34 that has received the sample, thereby creating a test liquid. This test liquid is 8 (11
Colorimetric measurements are performed in the light section, and the desired substance is quantitatively analyzed.

As shown in this example, using a pipetting device similar to that shown in Fig. 1 as the sample pipetting device of a biochemical analyzer has the advantage of increasing the analytical performance by increasing the pipetting speed, in addition to the above-mentioned effects. can be improved.

Note that the present invention is not limited to the above-mentioned example, and can be modified or changed in many ways. For example, in addition to the photoelectric method mentioned above, the initial liquid level can also be detected by a distance detector using ultrasonic waves, and if a dispensing nozzle cleaning device is added separately, the above-mentioned electrodes and optical fibers can be detected. It can also be detected using Even in the case of the mouth, the initial liquid level is detected only once before the dispensing operation, so the problem described in item (a) above does not occur. In addition, in FIG.
The motor 5 for raising and lowering the optical sensor consisting of the arm 7 and the light receiver 14 may be an encoder, or a pulse motor may be used if a detector is provided to detect the origin of the arm 7 and the optical sensor. That is, this pulse motor
The remaining amount of liquid in the tank can be calculated from the number of pulses.

Furthermore, the present invention can be effectively applied even when dispensing one type of liquid with one dispensing nozzle.

(Effects of the Invention) As described above, the present invention has the advantage that the presence or absence of liquid in a tank can be detected and the remaining amount can be easily calculated.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the configuration of an example of the dispensing device of the present invention;
The figure is a perspective view diagrammatically showing the configuration of essential parts of a biochemical analyzer using the dispensing device of the present invention as a reagent dispensing device. C, 20...control device, 21...counter, 22...
...Alarm device, 23...Keyboard. Patent applicant Olympus Optical Industry Co., Ltd. Figure 1

Claims (1)

[Claims] 1. A liquid level detection device that detects the level of a liquid contained in a tank; a dispensing nozzle that aspirates and discharges a predetermined amount of liquid contained in the tank; A dispensing nozzle lifting device that raises and lowers the dispensing nozzle to prevent the dispensing nozzle from entering the liquid; and a dispensing nozzle lifting device that raises and lowers the dispensing nozzle to prevent the dispensing nozzle from entering the liquid; It consists of a control device that outputs! Liquid remaining amount detection device that uses IO indication. 2. The remaining liquid amount detection device according to claim 1, further comprising an alarm device that generates an alarm signal when the remaining amount of liquid calculated by the control device becomes less than a predetermined level.