JPH03296428A - Mixing apparatus - Google Patents

Abstract

PURPOSE:To mix highly efficiently and speedily without bringing an object liquid into contact with a mixing means outside by installing means for suspending a vertical cylindrical container rotatably around each of two horizontal axes crossing perpendicularly and means for causing circular motion of the container in a horizontal plane. CONSTITUTION:A vertical cylindrical container 3 which is opened at the upper side is so hung by a hanging means consisting of container holding shafts 8a, 8b, and shafts 9a, 9b as to freely rotate the container around at least each of two perpendicularly crossing axes. Also, the container 3 is moved in a circle or an ellipse in a horizontal plane by a movement imparting means consisting of a circularly recessed part 6 in the container 3 and an eccentric rotary protrusion 12 on a motor 11. As a result, without bringing an object liquid into contact with a mixing means such as a stirring rod from the outside, highly efficient and speedy mixing is carried out.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is applicable to, for example, an analyzer that measures trace components in blood, a sample processing device, and especially an automated device that continuously analyzes and processes samples. This relates to the stirring device used.

(Prior Art) Generally, as a device for stirring a liquid in a container, there is a stirring bar in which stirring blades 33 are provided in a liquid 31 in a container 30, as shown in FIG. 6(a), for example. 32
There is a known method in which the sensor is inserted from the top and rotated or vibrated by a motor 34 or the like.

Separately, as shown in FIG. 6(b), a container 40 filled with liquid is supported by a predetermined horizontal shaft 41 so as to be able to vibrate, and a support plate 42 etc. to which this horizontal shaft 41 is fixed is reciprocated. A system is known in which the container 40 is caused to perform a pendulum motion by movement (for example, in the left-right direction in the figure), thereby stirring the liquid inside the container.

(Problems to be Solved by the Invention) The stirring device of the type shown in FIG. 6(a) has good stirring efficiency and rapid stirring because the stirring action is directly applied to the liquid by the stirring blades 33. There are advantages to doing so.

However, if there are multiple objects to be stirred, and the liquids to be stirred are not the same but different, for example, when stirring is performed in an analytical operation to measure trace components in blood, multiple sample liquids may be mixed. It is not suitable for continuous stirring using this device. This is because, in order to avoid the problem of sample liquid adhering to the stirring blade etc. being carried over to the next sample after each stirring is completed, a process of cleaning the stirring rod is required after each stirring operation to prevent contamination of each sample. This is because the processing time will be extended accordingly.

Furthermore, if this stirring device were to be used in an automated continuous analysis device, etc., the mechanism would become complicated as each step such as stirring and washing would be performed mechanically. In operations such as measuring medium-trace components, there is a problem in that the cleaning process becomes complicated in order to perform sufficient cleaning.

On the other hand, in the pre-shaking stirring device shown in FIG. 6(b),
Since there is no need to insert a stirring rod into the sample liquid, there is no particular problem with cross-contamination of samples. However, since the stirring is not sufficient, long stirring times are generally required.
Particularly in fields where rapid processing of a large amount of samples is required these days, such as the measurement of trace components in blood, there is a problem in that the demand for rapid processing cannot be satisfied.

Conventional stirring devices, which have mechanical and performance limitations as described above, are generally used in a limited manner depending on the field of use and the liquid to be stirred. However, in the current situation where it is important to avoid cross-contamination and a stirring device that can be passed through analysis equipment, etc., which is required to quickly stir a large amount of samples, has not yet been proposed, the above-mentioned conventional stirring device Although the drawbacks are recognized, stirring devices having the above configuration are often used for these purposes.

In view of the current situation, the present inventor developed a stirring device that can be used in applications where it is necessary to avoid mutual sample contamination, to avoid contamination between samples, and to quickly process a large amount of samples in a short period of time, such as for handling trace components in blood. This was made for the purpose of providing a stirring device for an analytical device that performs measurements.

That is, an object of the present invention is to provide a stirring device that can realize rapid stirring with high efficiency without bringing a stirring means such as a stirring rod into contact with the target liquid from the outside.

Another object of the present invention is to provide a stirring device in which a stirring step is serially combined with an analysis step, etc. to form a device.

Still another object of the present invention is to provide a stirring device suitable for realizing the stirring process as an automated operation.

(Means for Solving the Problems) A feature of the stirring device of the present invention that achieves the above objects is that the upper part of the vertical cylindrical container with an open top is rotated around at least two orthogonal horizontal axes. The container is configured to include a suspension means for suspending the container, and a movement imparting means for causing the lower part of the container to move in a circular or elliptical manner within a horizontal plane.

The container itself may be directly filled with the liquid to be stirred, or it may be a container in which a container such as a test tube filled with the liquid to be stirred is inserted and stored. good.

In the above, the suspension means that rotatably supports the upper part of the container around each of two orthogonal horizontal axes may be configured as a so-called gimbal type. for example,
A ring member surrounding the outer periphery of the upper part of the container with a gap therebetween and a fixing member disposed on the outer periphery of the ring member are provided, and the fixing member is provided on either the fixing member or the ring member on one diameter line of the ring member. A first shaft support mechanism is formed by engagement of the shaft and a bearing provided on the other of these, and a shaft support provided on either the fixing member or the container on a diameter line perpendicular to the first diameter line. The axis and
By forming a second shaft support mechanism by engaging a bearing provided on the other of these, the gimbal-type suspension mechanism described above can be constructed. Such a suspension mechanism is assembled in the upper half of the container, preferably near the upper edge, in order to provide sufficient agitation of the internal liquid. Although it depends on the height of the liquid inside the container and the speed of circular motion, it is not limited to this in particular. For example, by using it in conjunction with a means to maintain the stability of the container's posture, it is possible to maintain the center of gravity or a position lower than that. Although it may be suspended, it is generally better to hold it at a higher position than the liquid level.

Alternatively, the container may be held by a spherical sliding bearing.

Further, the motion imparting means in the stirring device of the present invention is for causing the container to undergo a rotary pendulum motion, and the container is suspended by the above-mentioned suspension means such that the upper part thereof can freely rotate around two horizontal orthogonal axes. Therefore, it is sufficient if the lower part of the container is moved in a circular or elliptical manner.

Specifically, such a mechanism includes a mechanism in which a member that engages with the bottom of the container in a circular or elliptical motion about a vertical axis, and a mechanism in which a member that exerts a magnetic attraction force on the bottom of the container is rotated. Examples include a mechanism for equalizing the container, and a mechanism for rotating the container by connecting it to a hook or the like at an intermediate height of the container.

The circular motion or elliptical motion given to the lower part of the container may be a uniform motion or a non-uniform motion.

(Function) The stirring device of the present invention having the above-mentioned configuration allows efficient and rapid stirring processing to be performed without the need to insert a stirring means into contact with the sample liquid.

(Example) The present invention will be described below based on embodiments shown in the drawings.

Example 1 The present invention will be explained below using an automatic sample pretreatment apparatus incorporating a stirring device shown in the drawings as an example.

The automatic sample pretreatment device incorporating a stirring device according to this example is a turntable that has a plurality of containers containing samples containing nucleic acids such as biological samples formed in a number of openings spaced apart in the circumferential direction of the turntable. After setting it in the chamber, the following processing operations are automatically performed continuously to extract the nucleic acid and prepare it in the form of a nucleic acid aqueous solution in the container.The specific sample processing procedure is as follows. It will be done.

l) Dispense a protein denaturant into the sample in the processing container and stir to denature and solubilize the protein in the sample.

2) Dispense ethanol into the sample solution containing the protein denaturant,
Stir to precipitate the nucleic acids.

3) Aspiration is performed from below the separation membrane forming the bottom of the container, and the nucleic acid is trapped as a precipitate on the microbial membrane.

4) In order to remove the protein denaturant remaining in the nucleic acid precipitate, wash by repeatedly dispensing 70% ethanol, stirring, and suctioning twice.

5) In order to dissolve the nucleic acid precipitate obtained on the separation membrane, pure water, buffer solution, etc. are dispensed and further stirred to finally obtain an aqueous nucleic acid solution.

In order to perform the above-mentioned series of processes, this device has several necessary mechanical elements: a stirring mechanism for mixing and stirring various reagents, a dispensing mechanism for simultaneously supplying reagents, etc. into a container, and a suction mechanism for collecting sediment. It is composed of a membrane separation mechanism for trapping by filtration, a turntable movement mechanism for moving multiple processing containers to each processing section, etc., and the above series of processing operations can be automatically performed on multiple containers containing samples. It is designed to be able to be performed continuously.

Next, details of an automatic sample pretreatment apparatus incorporating a stirring device according to the present invention will be described with reference to the drawings.

FIG. 3 is a sectional view schematically showing the present processing apparatus.

Does this device have a bottom? The container 3 shown in FIG.
a turntable 2 for holding and transporting the sample liquid, a container holding ring 1 provided at a plurality of openings on the turntable, a turntable driving motor 29 for rotating the turntable 2, and stirring of the sample liquid in the container 3. A stirring drive motor 11 for performing the process, a suction nozzle 15 used to membrane-separate the precipitate in the sample liquid, a vacuum pump unit (not shown) (vacuum tank, waste liquid trap bottle, and pressure regulator), reagents necessary for the process, etc. It consists of a plurality of dispensing pumps and dispensing nozzles (not shown) for dispensing into the container 3, a controller (not shown) controlling each part of the device, and the like.

In FIG. 1, reference numeral 1 denotes a container holding ring as a ring member, and a pair of shafts 9a, 9b extending radially outward on a diameter line is provided on the outer periphery of the ring, and the shafts 9a,
Container holding shafts 8a and 8b are provided inward from the inner periphery of the ring on a diameter line perpendicular to 9b.

Reference numeral 2 designates a turntable, which has a circular opening 2a into which the container holding ring 1 is inserted, and shafts 9a and 9b of the container holding ring 1 formed in a part of this opening 2a.
Bearings 10a and 10b are provided to support the shaft rotatably around its axis.

This turntable 2 has a plurality of openings 2a along the circumferential direction as shown in FIG. 2, and a cylindrical container 3 is suspended in the openings as described below.
These multiple containers 3 are moved from the container insertion position (arrow A position in Figure 2) to the stirring position (arrow B position in Figure 2) to the multiple reagent dispensing position by intermittent rotation of the turntable drive motor 29. position (arrow C position in the figure), nucleic acid membrane separation position (arrow position in the figure), and further to the container extraction position (in this device, the same position as the container insertion position A) according to the order of processing operations. It is provided.

The container filled with the sample in 3 above is one in which all the processing in this device is performed, and in this example, the upper 3
The outer periphery of a is provided with a large diameter, the outer periphery of the lower part 3b is provided with a small diameter, and the upper part 3a has vertical grooves 7a and 7b that are open to the lower side.
is formed up to a certain height near the upper edge. Container holding shafts 8a and 8b are fitted into these vertical grooves. Also, on the bottom of this container 3, the following eccentric rotation projection 12 is provided.
A circular recess 6 is formed for loose fitting. Furthermore, this container has a bottom formed by a membrane 4 and a suction port 5, and has a structure that allows membrane separation of nucleic acids as precipitates. The suction port 5 is formed further inside the circular recess 6 and has a downwardly wide conical shape, so that it can be tightly fitted with a suction nozzle 15, which will be described later.

The container 3 having such a configuration is lowered from above the container holding ring 1 so as to be inserted into the vertical groove 7a,
7b from the groove opening at the lower end of the container holding shaft 8a, Bb.
By fitting the container with the container holding ring 1, a suspension that can freely rotate around two horizontal axes can be obtained.

Reference numeral 11 denotes an agitation drive motor as a motion imparting means, which is provided at one or more locations (one location in the figure) in the circumferential direction of the turntable at an agitation position (arrow B position shown in FIG. 2). A cylindrical eccentric rotation protrusion 12 that can be loosely fitted into the circular recess 6 at the bottom of the container 3 is provided at the upper end of the rotation shaft 11a extending upward. The agitation drive motor 11 is moved by a vertical movement mechanism (not shown) between a waiting position in the lower part and an upward agitation drive position shown in the figure.

Note that the fixing plate 14 placed at the top of the container at the stirring position
is moved downward by the solenoid 13, so that the container 3
This is for correcting the posture of the container 3 when the cylindrical eccentric rotating protrusion 12 is fitted into the circular recess 6 at the bottom of the container.

FIG. 4 shows the relationship between a mechanism and a container for trapping precipitates on the membrane 4. In this figure, reference numeral 15 denotes a suction filter provided at one or more locations (one location in the figure) in the circumferential direction of the turntable for nucleic acid membrane separation (the position indicated by the arrow in Figure 2). This is a suction nozzle as a means, and an O-ring 16 is provided at the tip thereof so as to tightly fit into a suction port 5 provided further inside the circular recess 6 at the bottom of the container. On the other hand, the suction nozzle 15 is connected to a waste liquid trap bottle, which is under pressure by a vacuum pump, through a Teflon tube (not shown), and the waste liquid sucked up by the suction nozzle 15 is trapped here. Become.

Note that the pressure inside the waste liquid trap bottle is preferably kept within a certain range so that the driving time of the vacuum pump is controlled by the function of a pressure regulator. Then, the suction nozzle 15 is moved up by a vertical movement mechanism (not shown) from a waiting position downward toward the bottom of the container 3, and after being tightly fitted with the suction port 5, the suction nozzle 15 performs suction and filtration as membrane separation. conduct.

Note that the fixing plate 1 placed at the top of the container at the membrane separation position
Similarly to the fixing plate 14 in the stirring position, 8 is for correcting the posture of the container 3 when the suction nozzle 15 is hermetically fitted to the suction port 5 at the bottom of the container.

Multiple types of reagent dispensing positions set at multiple locations in the upper circumferential direction of the turntable 2 (arrow C position shown in FIG. 2)
is provided with a dispensing nozzle (not shown), the tip of which is directed toward the opening 2a on the turntable, and the reagent discharged from the dispensing nozzle is supplied from various reagent tanks by a plunger-type dispensing pump. Ru.

The processing device of this example incorporating the stirring device described in the example is one that automatically extracts nucleic acids after, for example, manually setting containers containing multiple samples into the container holding ring. However, this processing device has an analytical device such as D
Viral DNA (
It is also possible to incorporate a detection device for detecting (RNA) or to combine with an independent nucleic acid analyzer and use it as an automatic analyzer that includes sample pretreatment. In the latter case, if the container containing the purified nucleic acid aqueous solution is to be extracted from the container holding ring of the processing device and transferred to the analysis device, a chuck attached to the tip of a robot arm or the like may be used, for example. This can be done by lifting the container.

The operation of the stirring device incorporated in the automatic sample pretreatment apparatus having the above configuration will be described below.

First, the container holding ring 1 is in the container insertion position shown as the arrow A position in FIG. 2, with no container fitted.
A plurality of containers 3 are sequentially lowered and inserted into the container by hand or by using a chuck of a robot arm or the like. As a result, the container 3 is rotatable around the container holding shafts 8a and 8b, and the container holding ring 1 is supported by the turntable 2 so as to be rotatable around the shafts 9a and 9b. Freely swings around two orthogonal axes.

After setting a plurality of containers 3 on the turntable 2,
The series of processing operations described above is automatically started. The mechanical parts that perform each processing operation are controlled by a controller (not shown), and all containers on the turntable are sent at the appropriate time according to pre-programmed processing procedures and various parameters depending on the type, form, and amount of the sample. The samples are automatically transferred to each processing section in sequence and subjected to processing for nucleic acid extraction.

When the container 3 moves onto the stirring drive motor 11 at the stirring position during various processing operations, the solenoid 13 first
Move the fixing plate 14 downward to hold down the top of the container 3,
The posture of the stirring drive motor 11 and the container 3 are corrected and stabilized in a substantially upright state so that their central axes coincide with each other.

Next, the lower stirring drive motor 11 is moved upward by a vertical mechanism (not shown), so that the eccentric rotation protrusion 12 is fitted into the circular recess 6 at the bottom of the container. In this case, when the inner diameter of the circular recess 6 rotates the stirring drive motor 11, the eccentric rotation protrusion 12
If the diameter is larger than the diameter of the locus drawn by the outer periphery of the agitation drive motor 11, it is preferable that the fitting be made larger than the diameter of the locus drawn by the outer periphery of the agitation drive motor 11, since the fitting can be performed without any problem regardless of the rotational position of the eccentric rotation protrusion 12 with respect to the rotation axis of the stirring drive motor 11. . However, if the configuration is such that the rotational position of the agitation drive motor rotation shaft 12 can be determined, the inner diameter of the circular recess can be made larger than the outer diameter of the eccentric rotation protrusion 12, thereby allowing the same fitting as described above. Furthermore, in this case, there is no need to consider how to engage the eccentric rotating protrusion 12 with the inner wall of the circular recess 6 as described below.

After this fitting is completed, the fixing plate 14 is moved upward so that the container 3 can freely swing again, and the turntable 2 is slightly rotated in order to engage the eccentric rotary protrusion 12 with the inner wall of the circular recess 6. After that, rotation of the stirring drive motor 11 is started. As a result, the eccentric rotational movement of the eccentric rotation protrusion 12 is transmitted to the container 3, causing the bottom of the container to perform a circular motion, and the upper part of the container is suspended freely to swing around two orthogonal horizontal axes as described above. Therefore, the container 3 as a whole performs a conical pendulum motion with the intersection of the two horizontal axes as the fulcrum. As a result, the liquid in the sample container is forcibly rotated in a swirling manner, resulting in efficient stirring processing.

FIG. 1(a) shows an example of the state of the liquid during stirring.

Note that by setting the center of gravity of the container eccentrically in the horizontal direction from the center of the circular container by, for example, providing a biased weight on the container, rotation of the turntable for the above-mentioned engagement becomes unnecessary, and the above-mentioned fixing plate 14 It is also possible to provide the container in such a way that the eccentric rotation protrusion 12 and the inner circumferential wall of the circular recess 6 of the container engage with each other as the container naturally tilts during upward movement.

After the stirring is completed, the stirring drive motor 11 is stopped and then moved downward to release the fitting between the eccentric rotation protrusion 12 and the circular recess 6. Furthermore, if there is a container waiting for its turn to be stirred, the turntable 2 is rotated and the stirring process is performed in the same manner.

Note that when stirring is performed using the above configuration example, it is often preferable that the liquid level in the container is approximately 1/2 or less of the height from the bottom of the container 2 to the hanging position. Also, the dimensions of the container,
The rotational speed, amplitude, etc. may be adjusted as appropriate depending on the properties, amount, and degree of stirring of the target liquid.

Example 2 This example shown in FIG. 5 can be directly applied to the automatic sample pretreatment apparatus described in Example 1, and the upper large diameter part of the container 3 of Example 1 with the longitudinal grooves 7a and 7b can be replaced with The removed simple cylindrical sample container 23, the container holder 24 into which the sample container 23 is inserted and held, and the container holder 24! It is constituted by a container holder retaining ring 27 etc. that is held in a freely swinging manner, and also shows an example in which a magnet is used as the motion imparting means.

In the same figure, the container holder holding ring 27 has a pair of shafts 20a extending radially outward on the diameter line of its outer periphery.
, 20b are provided, and bearings 2fa and 21b are provided that rotatably support a pair of shafts 19a and 19b provided radially outward of the container holder 24 on a diametric line perpendicular to the shafts 20a and 20b. There is.

In this example, the turntable 2 includes a bearing 22a that rotatably supports a pair of shafts 20a and 20b provided in the container holder at each of a plurality of openings provided along the circumferential direction of the opening 2a; 22b, and these plurality of container holders can be moved to each processing operation position by intermittent rotation of the turntable 2, as in the first embodiment.

Incidentally, fitting the sample container downward into the container holder 24 or removing it in an upward position can be easily done manually, or it can also be done automatically using a chuck of a robot arm or the like.

In this example, the container holder 24 is always suspended from the opening of the turntable 2, and is used to insert and remove the sample container 23 into and from the internal space. , when setting the container 3 on the turntable, the vertical grooves 7g, 7b of the container and the container holding shaft 8g.

There is no need for fitting 8b.

Next, the motion imparting means in this example will be explained. In this example, a first magnet 25 is attached to the bottom of the container holder 24.
embedded, and the output shaft 11 of the stirring drive motor 11 on the other hand.
A second magnet 26 that exerts a magnetic attraction force with the first magnet 25 is embedded in an eccentric position on the upper surface of the member that rotates together with the motor, and as a result, as the motor rotates, the bottom of the container holder 24 is designed to perform circular motion.

With this configuration, as in the first embodiment, a conical pendulum motion is imparted to the sample container 23 fitted and held inside the container holder 24, resulting in the effect of obtaining highly efficient and rapid stirring.

As in Example 1, the dimensions of the container, rotational speed, amplitude, etc. may be adjusted as appropriate depending on the properties, volume, and degree of stirring of the target liquid; however, in this example, Depending on the rotational speed of the drive side magnet 26, etc., the centrifugal force of the container may exceed the attraction force between the magnets, causing disturbances in the rotational movement of the container. It is necessary to take this into account.

(Effects of the Invention) As explained above, the stirring device of the present invention eliminates the problem of contamination of the sample liquid because there is no external contact of stirring means such as a stirring rod with the target liquid, and therefore a cleaning step is required. The effect is that it is not necessary.

Furthermore, since the container is moved in a conical shape, it is possible to achieve highly efficient and rapid stirring of the liquid to be stirred.

Furthermore, when a stirring process is combined with an analysis process or the like to form an analytical device or the like, it is possible to provide a stirring apparatus that can be used to perform the stirring process.

Furthermore, when automating the stirring process, the stirring device of the present invention has the advantage that it can be formed with a suitable structure.

[Brief explanation of the drawing]

FIG. 1(a) is a front view including a partial cross section showing an outline of the configuration of Example 1 of the stirring device according to the present invention, FIG. 1(b) is a front view of the container, and FIG. 1(c) is a front view including a partial cross section. Figure 2 is a cross-sectional view to explain the suspension mechanism, and is a diagram showing the outline of the entire turntable and the relationship between the container insertion position, stirring position, reagent dispensing position, nucleic acid membrane separation position, and extraction position. be. FIG. 3 is a sectional view showing an outline of an automatic sample pretreatment apparatus incorporating a stirring device according to the present invention. FIG. 4 is a front view including a partial cross section for explaining the suction nozzle and the suction port at the membrane separation position. FIG. 5(a) is a front view of the second embodiment, FIG. 5(b) is a sectional view taken along line A-A, and FIGS. 6(a) and (bl are for explaining the conventional example of the stirring device. It is a figure. 1... Container holding ring 2... Turntable 3
...Container 4...R membrane 5...Suction port 6...Circular recesses 7a, 7b...Vertical grooves 8a, 8b...Container holding shafts 9a, 9b, 1
9a, 19b, 20a, 20b-axis 10a, 10b, 2
1a, 21b, 22a, 22b---Bearing 11...
- Stirring drive motor 12... Eccentric rotation protrusion 13.17... Solenoid 14.18... Fixing plate 15... Suction nozzle 16... O-ring 23... Sample container 24... Container Holder 25... First magnet 26... Second magnet 27... Container holder holding ring 28... Positioning sensor 29... Turntable drive motor 30... Container 31... Sample Liquid 32...Stirring rod 33...Stirring blade 34-...Motor 41...Horizontal axis Fig. 40...Container 42...Support plate and other 4 people Fig. 2 Fig. Fig. 5 (a ) Figure (b,)

Claims (1)

[Scope of Claims] 1. Suspending means for rotatably suspending an upwardly open vertical cylindrical container about at least two orthogonal horizontal axes;
A stirring device comprising: a motion imparting means for causing the container to move in a circular or elliptical manner within a horizontal plane. 2. The stirring device according to claim 1, wherein the cylindrical container has an inner space that opens upward into which a sample container filled with the liquid to be stirred is inserted. 3. The stirring device according to claim 1 or 2, characterized in that the motion imparting means has a member that engages in a convex-concave manner with the bottom of the container, and the member makes circular or elliptical motion about a vertical axis. . 4. The agitation according to claim 1 or 2, characterized in that the motion imparting means has a member that exerts a magnetic attraction force with the bottom of the container, and the member moves in a circular or elliptical motion. Device. 5. In any one of claims 1 to 4, the hanging means includes a ring member surrounding the outer periphery of the upper part of the container with a gap, a fixing member arranged on the outer periphery of the ring member, and one of the ring members. a first shaft support mechanism comprising a shaft provided on either the fixed member or the ring member on a diametrical line and a bearing provided on the other of the fixed member or the ring member; A second shaft support mechanism consisting of a shaft provided on either the fixing member or the container on another diameter line orthogonal to the diameter line, and engagement of a bearing provided on the other of the fixing member or the container. A stirring device comprising: 6. In claim 5, the first shaft support mechanism is configured such that a shaft extending from the outer periphery of the ring member is fitted into a bearing of the fixed member so as to freely rotate around the shaft, and the second shaft support mechanism is ,
A stirring device characterized in that a shaft extending inward from an inner periphery of a ring member is fitted into a bearing provided on an outer periphery of a container so as to freely rotate around the shaft.