JP2005274471A - Dispensing device, and automatic analyzer provided therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To remove a bubble trapped in a pressure sensor connection container chamber, in a dispensing device provided with a pressure sensor for detecting abnormality in dispensing. <P>SOLUTION: An inside 9a of the chamber of a pressure sensor connection container is made conical, and is installed to bring a conical apex into a vertical upper side. Flow-in outlets 9b, 9c are provided in a tangential direction of a bottom face of a cone and an apex part, and the pressure sensor is arranged to bring a pressure receiving face into contact with the bottom face of the cone. System water 7 flows in from the flow-in outlet 9b to generate a vortex flow in the connection container chamber inside 9a, so as to remove the bubble deposited on an in-chamber inner wall. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a dispensing device for sucking and discharging (hereinafter referred to as dispensing) a predetermined amount of a liquid sample or reagent from one container to another, and an automatic analyzer equipped with the dispensing device. The present invention relates to a dispensing device including a pressure sensor and an automatic analyzer including the same.

  For example, in an automatic analyzer such as a biochemical automatic analyzer or an immune automatic analyzer that performs qualitative / quantitative analysis of a specific component in a biological sample such as blood or urine, a liquid sample or reagent is contained in a container (sample container, A dispensing device is provided for reacting a sample and a reagent by automatically aspirating and discharging (hereinafter referred to as dispensing) from another container (such as a container) to another container (such as a reaction container).

  Since these dispensing devices require extremely high dispensing accuracy (dispensation reproducibility and accuracy), in order to accurately transmit the pressure generated by pressure generating means such as syringes and diaphragms, Is usually filled with a liquid such as purified water (hereinafter referred to as system water).

  In patent document 1, it is proposed to provide a pressure sensor in the flow path. If there is a deposit in the liquid to be sucked and the suction nozzle is clogged, or if air is sucked in without sucking the liquid sucked by the suction nozzle, the pressure in the flow path changes. It is possible to prevent erroneous analysis by using this to detect dispensing abnormality and issue an alarm.

JP 2002-333449 A

  A pressure sensor generally uses a diaphragm having a large diameter in order to measure a low pressure of about −98 kPa to 98 kPa (gauge pressure) with high sensitivity, and the diameter is often about 10 mm or more. . On the other hand, since the diameter of the pipe connected to the pressure sensor is as thin as several millimeters, the cross-sectional area of the flow path suddenly expands in the connection container chamber connecting the pipe and the pressure sensor, and the flow in this part is disturbed and the flow velocity decreases. , Bubbles in the flow path tend to stay in the pressure sensor portion.

  Although a pressure sensor with a small diaphragm diameter can be used to suppress turbulence in the flow and make it easier to remove bubbles, a pressure sensor with a small diaphragm diameter is generally difficult to manufacture, so it is compared with a general-purpose pressure sensor. There is a problem that becomes extremely expensive.

  In the dispensing device, if bubbles remain in the dispensing flow path, the pressure transmission characteristics change accordingly, which may adversely affect dispensing accuracy.

  The present invention relates to a dispensing device equipped with a pressure sensor for the purpose of detecting abnormalities during dispensing from pressure fluctuations during dispensing. An object is to provide an apparatus and an automatic analyzer including the apparatus.

  The configuration of the present invention for achieving the above object is as follows.

Nozzle for sucking and discharging liquid, pressure generating means connected to the nozzle for generating pressure for sucking and discharging liquid, and pressure for measuring the pressure in the flow path including the nozzle and the pressure generating means A dispensing device comprising a sensor,
The connection between the pressure sensor and the flow path has a conical shape in the flow path, and the apex of the cone is arranged vertically upward. A dispensing apparatus in which an inlet / outlet is provided and a pressure receiving surface of the pressure sensor is disposed on a bottom surface of a cone.

  In order to efficiently remove the bubbles in the pipe, it is efficient that the bubbles that have escaped from the top of the cone escape from the nozzle into the atmosphere. It is preferable to connect a pipe on the nozzle side. Of course, if a trap or the like for removing bubbles is provided in the pipe, it is not always necessary to connect the pipe on the nozzle side to the liquid inlet / outlet at the apex.

  The present invention has an effect of removing bubbles effectively when the diameter of the pressure sensor is larger than that of the pipe. The flow diameter of a general dispensing apparatus is several mm, and the diameter of a general pressure sensor for measuring a low pressure region is about 10 mm. In such a case, the effect is great. Of course, the number 10 mm is not critical in itself, and is merely defined using the general dimensions of a general pressure sensor as a guide. Considering the AND of pressure sensor cost and bubble removal effect, the sensor diameter is preferably 5 mm or more and 30 mm or less.

  Although the relationship between the pipe diameter and the pressure sensor diameter, if the pressure sensor diameter is too large, vortices are not generated well, so the bubble removal effect cannot be expected. On the other hand, the same is true if the pressure sensor diameter and the pipe diameter are too close. Although not verified experimentally, a pressure sensor diameter within several to 10 times the pipe diameter is considered preferable.

  According to the present invention, it is possible to remove bubbles even in a pressure sensor mounting portion where bubbles are likely to remain, and a stable pressure transmission characteristic can be obtained even in a dispensing device equipped with a pressure sensor. Thereby, the function which judges the abnormality at the time of dispensing can be provided, without having a bad influence on dispensing accuracy.

  In addition, if the present invention is used, a highly sensitive sensor having a large diaphragm diameter can be adopted, so that a highly reliable and reliable determination can be made in the dispensing abnormality determination function.

  Since the present invention does not use a special mechanism for removing bubbles, the bubble removing means can be provided at a very low cost. Also, since no mechanism is used, there is no failure potential and maintenance is free.

  Examples of the present invention will be described below.

  FIG. 1 is a schematic configuration diagram of a dispensing apparatus according to the present invention.

  The nozzle 1 and the syringe 2 are connected via pipes 3a and 3b, and the syringe 2 is further connected to the solenoid valve 4 via a pipe 3c. The dispensing operation is performed by moving the plunger of the syringe 2 up and down while the electromagnetic valve 4 is closed. The electromagnetic valve 4 is further connected to a water supply pump 5 through a pipe 3d. The electromagnetic valve 4 is opened, and the system water 7 in the tank 6 is fed by the water supply pump 5 so that the system water is introduced into the dispensing flow path. Filling and replacement are performed.

  In order to detect an abnormality at the time of dispensing, a pressure sensor 8 having a diaphragm diameter of 14.5 mm is connected to a dispensing flow path (flow path system 1.5 mm) via a connection container 9. In addition, there is no problem anywhere in the connection place of the pressure sensor 8 as long as it is inside the flow path system when the dispensing operation is performed, and in FIG. 1, it is connected between the nozzle 1 and the syringe 2, but the syringe 2 and the electromagnetic valve. It may be between 4.

  FIG. 2 shows a detailed structure of the connection container 9 and a method for attaching the pressure sensor 8.

  The connecting container chamber 9a has a conical shape and is installed so that the apex of the cone is vertically upward. There is an inflow / outlet port 9b in the tangential direction of the bottom peripheral surface of the cone, an inflow / outlet port 9c at the apex, the inflow / outlet port 9b is connected to the water supply pump side pipe, and the inflow / outlet port 9c is connected to the nozzle side pipe. Thereby, when the system water 7 is caused to flow into the connection container chamber 9a by the water supply pump 5, the system water 7 flows in from the inflow / outflow port 9b and comes out to the inflow / outlet port 9c.

  The pressure sensor 8 is attached so that the diaphragm (pressure receiving surface) 8a becomes the bottom of the cone. The pressure sensor 8 may be fixed as long as the system water does not leak from the connection portion, and is matched to the shape and specifications of the pressure sensor. If the sensor has a threaded portion, it may be screwed or may be pressed from the back of the sensor with a fixing bracket.

  Next, a mechanism for removing bubbles in the connection container chamber will be described.

  The system water flowing in from the inlet / outlet 9b causes a swirling flow along the circumferential surface of the room 9a. Due to the centrifugal force caused by the swirling flow, the system water flows spirally on the inner wall of the indoor 9a, and at this time, the bubbles remaining on the inner wall of the indoor 9a are swept away by the vigorous swirling flow. Bubbles with a light specific gravity gather at the center of the cone due to the centrifugal force, float as they are, and are pushed out from the inlet / outlet 9c. Depending on the flow rate, while the system water is flowing, there may be a case where a set of bubbles cannot be lifted while gathering at the center of the cone, but in this case, if the system water is allowed to flow intermittently, When the supply of system water is stopped, it floats in the vicinity of the inlet / outlet 9c, and when it is supplied again, it is pushed out as it is, so it can be removed.

  FIG. 3 shows a configuration example of the automatic analyzer according to the embodiment of the present invention. First, a sample disk 201 for setting a liquid sample in the apparatus, a sample dispensing probe 204 for dispensing the liquid sample, a reaction cell 211 that is a reaction container for the liquid sample and the reagent, and a reaction disk 206 that is a holder thereof, A plurality of reagent disks 202 and 210 for setting reagents according to measurement items, a plurality of reagent probes 203 and 209 for dispensing reagents, and a reaction between the liquid sample dispensed in the reaction cell 211 and the added reagent It comprises a stirring mechanism 208 for stirring for stabilization, a cleaning mechanism 207 for sucking and cleaning waste liquid in the reaction cell, and a control section for these mechanisms and analysis. The set of liquid samples may be based on a sample rack instead of the sample disk. As for the reagent dispensing moving mechanism, the reagent probe may be moved in a plane by an XY mechanism instead of rotational movement.

It is a schematic block diagram of the dispensing apparatus in connection with this invention. It is a figure which shows the detailed structure of the connection container in this invention, and the attachment method of a pressure sensor. It is a schematic block diagram of the automatic analyzer which can apply the dispensing apparatus of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Nozzle, 2 ... Syringe, 3a, 3b, 3c, 3d ... Piping, 4 ... Solenoid valve, 5 ... Water supply pump, 6 ... Tank, 7 ... System water, 8 ... Pressure sensor, 8a ... Diaphragm (pressure receiving surface), 9 ... Connection container, 9a ... Indoor, 9b, 9c ... Inlet / outlet, 10 ... Packing.

Claims (4)

A nozzle for sucking and discharging liquid;
Pressure generating means connected to the nozzle for generating pressure for sucking and discharging the liquid;
A pressure sensor for measuring the pressure in the flow path including the nozzle and the pressure generating means;
In a dispensing device with
The connection between the pressure sensor and the flow path has a conical shape in the flow path, and the apex of the cone is arranged vertically upward. A dispensing apparatus, wherein an inlet / outlet is provided and a pressure receiving surface of the pressure sensor is disposed on a bottom surface of a cone. The dispensing device according to claim 1,
2. A dispensing apparatus according to claim 1, wherein a pipe on the nozzle side is connected to a liquid inlet / outlet of the apex of the cone. The dispensing apparatus according to claim 1 or 2,
A dispensing apparatus, wherein the diameter of the bottom of the cone is 5 mm or more and 30 mm or less. A reaction vessel for mixing the reagent and the sample;
Measuring means for measuring the reaction in the reaction vessel;
Dispensing means for dispensing a sample into the reaction vessel;
In an automatic analyzer equipped with
An automatic analyzer characterized in that the dispensing means is the dispensing apparatus according to any one of claims 1 to 3.

Images