JPS6110748Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a stirring device suitable for use in an apparatus for chemically analyzing liquids such as blood.

2. Description of the Related Art Automated chemical analyzers that automatically analyze sample liquids such as blood and urine have been developed and used in clinical, chemical, pharmaceutical, and other fields.

In general, this automatic chemical analyzer performs multiple types of analysis on the same sample liquid, so it injects sample liquid in μ order and reagents according to the analysis items in ml order into multiple reaction tubes. The reaction is stirred and reacted, and the test liquid is measured colorimetrically during the reaction process or after the reaction is completed.

However, in conventional devices, the reaction tube is kept at a predetermined temperature (for example, 37°C), but the reagent that is injected into the reaction tube in a large amount relative to the sample liquid is at room temperature (around 20°C). While the reaction tube is cooled, the reaction tube is further cooled by inserting a stirring rod into the reaction tube to stir the sample liquid and reagent to obtain a test liquid.

For this reason, in conventional automatic chemical analyzers, the sample solution and reagent do not reach the specified temperature (37°C) for a considerable period of time after they start reacting, making it impossible to obtain accurate reaction results. .

As a device that can eliminate these drawbacks, Japanese Utility Model Publication No. 15896/1987 describes a stirring device in which a reciprocatingly rotatable stirring shaft and stirring blades are hollow to allow heat exchange fluid to flow through them. . However, in this stirring device, since the stirring shaft and the stirring blade are reciprocally rotated, the structure of the rotation mechanism including the rotation means is complicated. Also,
Since the heat exchange fluid circulates while reciprocatingly rotating together with the stirring shaft and stirring blades, the connection between the flexible pipe for supplying and discharging the heat exchange fluid and the fitting for supplying and discharging the stirring shaft may become twisted. It has the disadvantage of poor durability.

SUMMARY OF THE INVENTION The object of the present invention is to eliminate the above-mentioned drawbacks and to provide a stirring device that has a simple structure and is suitably arranged to stir a test liquid without lowering its temperature.

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

FIG. 1a is a sectional view showing the structure of an example of the stirring device of the present invention. The stirring rod 1 is constructed by coating the metal surface with a plastic material such as Teflon or polypropylene that is corrosion resistant to the test liquid, and is attached to a cylindrical stirring rod holder 2. Stirring bar presser 2 is bearing 3
It is rotatably attached to the fixed member 4 via a and 3b. Further, a gear 5 is fixed to the stirring bar presser 2. The motor 6 is attached to a holding member 7 fixed to the fixed member 4, and its output shaft has a
A gear 8 that meshes with a gear 5 provided on the stirring bar holder 2 is fixedly provided. Therefore, the stirring bar 1 is rotated in a predetermined direction via the gears 8 and 5 by the drive of the motor 6. As shown in FIG. 1b, the tip of the stirring rod 1 into which the liquid to be tested enters is formed into a flat plate shape for easy stirring.

In such a configuration, in this example, the stirring rod holder 2 is loosely fitted, the heater rod 9 is inserted so as to extend inside the stirring rod 1, and this is fixed to the fixing member 4 via a suitable holding member. . In addition, a temperature sensor 10 such as a thermistor is provided in a part of the stirring rod 1 that does not enter the test liquid, and this detects the temperature of the stirring rod 1 and controls the power supply circuit 11 of the heater rod 9 on and off. Always maintain the test liquid at a predetermined temperature.

In this way, the liquid to be tested will not be cooled down due to the intrusion of the stirring rod 1. Furthermore, when applied to the above-mentioned automatic chemical analyzer, the sample liquid cooled by injection of reagents can be quickly raised to a predetermined measurement temperature.

As described above, according to the present invention, since the stirring rod rotates independently of the heater rod, its rotation can be easily controlled. Furthermore, since the heater rod does not rotate together with the stirring rod, but is fixed to the main body of the device, the electrical connection between the heater rod and its power circuit can be easily and easily made without using slip rings or the like. In addition, the connected state can be maintained stably for a long period of time. Furthermore, in the present invention, since the test liquid is stirred by the stirring member whose temperature is controlled to a predetermined temperature, the test liquid can be maintained at a desired temperature. Furthermore, when the present invention is applied to an automatic chemical analyzer as described above, it is also possible to quickly raise the sample liquid cooled by injection of the reagent to the measurement temperature.

[Brief explanation of the drawing]

FIG. 1a is a sectional view showing the configuration of an example of the stirring device of the present invention, and FIG. 1b is a perspective view showing an example of the shape of the test liquid inlet tip of the stirring rod shown in FIG. 1a. 1... Stirring bar, 2... Stirring bar holder, 3a, 3b
... Bearing, 5, 8 ... Gear, 6 ... Motor, 9
... Heater rod, 10 ... Temperature sensor, 11 ...
...Power circuit.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A stirring device used in biochemical analysis that is inserted into a container containing a test liquid and stirs the test liquid, which rotates in the test liquid to stir the test liquid. a stirring rod, a means for continuously rotating the stirring rod about its longitudinal axis, and a heater rod fixed to the device body and inserted into the center of rotation of the stirring rod for heating the stirring rod, A stirring device characterized in that the stirring rod rotates and stirs independently of the heater rod. 2. A request for registration of a utility model characterized in that a temperature sensor is provided at a position where the stirring rod is not immersed in the test liquid, and heating of the stirring rod by the heater rod is controlled based on the output of the temperature sensor. The stirring device according to item 1.