JP2012170417A - Stirring apparatus and culture tank - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stirring apparatus and a culture tank, stirring a culture solution with power saving, and preventing sedimentation of a microbe.SOLUTION: The stirring apparatus 1 includes: a movable member 15 that can be displaced between a state A that can hold gas supplied from below in the solution and a state B that can discharge the held gas to the outside; support means 31, 33, 35, 37 vertically movably supporting the movable member 15; and the state changeover means 31, 33, 35, 37 bringing the movable member 15 into the state B when the vertical position of the movable member 15 is higher than a prescribed upper limit position, and bringing the movable member 15 into the state A when the vertical position of the movable member 15 is lower than a prescribed lower limit position. The movable member 15 ascends or descends in the solution according to a held amount of the gas.

Description

  The present invention relates to a stirrer used for culturing microorganisms (for example, algae) and a culture tank.

  Conventionally, raceway type culture tanks are used for culturing microorganisms (for example, algae). The raceway type culture tank is provided with a rotating paddle, and the rotation of the paddle causes a flow of the culture medium in a certain direction to prevent the precipitation of microorganisms. However, depending on the shape of the raceway type culture tank, a part where the flow of the culture solution becomes gentle may occur, and microorganisms may precipitate in that part. When the precipitation of microorganisms occurs, the cultivation of microorganisms is hindered and the growth is delayed. Regarding this problem, a technique for preventing precipitation using ultrasonic waves (see Patent Document 1) is disclosed.

JP 7-298869 A

  However, the technique of Patent Document 1 requires a large amount of power in order to continuously generate ultrasonic waves. This invention is made | formed in view of the above point, and aims at providing the stirring apparatus and culture tank which can stir a culture solution with power saving and can prevent precipitation of microorganisms.

  The stirring device of the present invention includes a movable member that is displaceable between a state A in which a gas supplied from below in a liquid can be held and a state B in which the held gas can be discharged to the outside. When the position of the movable member in the vertical direction is higher than a predetermined upper limit position, the movable member is set to the state B, and the position of the movable member in the vertical direction is And a state switching means for setting the movable member to the state A when below a predetermined lower limit position, and the movable member ascends or descends in the liquid according to the amount of gas held. .

  In the stirring device of the present invention, the movable member holds the gas supplied from below in the state A, and moves up by its buoyancy, and in the state B, releases the held gas to the outside and descends. It repeats with operation alternately. As a result, the culture solution can be stirred to prevent the precipitation of microorganisms. Further, it is not always necessary to separately prepare a power source for driving the movable member up and down, and it is not necessary to use ultrasonic waves as in the technique of Patent Document 1. Therefore, stirring can be performed with power saving. Further, since the gas supplied from below gradually rises together with the movable member, the gas-liquid contact time becomes long. Therefore, gas components are likely to dissolve in the culture solution.

Examples of the stirring device of the present invention include the following (a) and (b). That is,
(A) The movable member is composed of a plurality of unit members whose mutual positional relationship is variable. The state A is a state in which a hollow container shape capable of holding a gas supplied from below is formed by the plurality of unit members. The state B is a state in which a gap for allowing the gas to escape upward exists between the plurality of unit members. The state switching means supports the plurality of unit members so as to be in the state B when the position of the movable member in the vertical direction is higher than the upper limit position, and positions the movable member in the vertical direction. The support means supports the plurality of unit members so as to be in the state A when is lower than the lower limit position.

This stirring apparatus can perform stirring with power saving. Further, since the gas supplied from below gradually rises together with the movable member, the gas-liquid contact time becomes long. Therefore, gas components are likely to dissolve in the culture solution.
(B) The movable member includes a gas holding unit capable of holding a gas supplied from below in the liquid, and a valve capable of releasing the gas held in the gas holding unit to the outside. The state switching means opens the valve when the position of the movable member in the vertical direction is higher than the upper limit position, and when the position of the movable member in the vertical direction is lower than the lower limit position, The valve is closed.

  This stirring apparatus can perform stirring with power saving. Further, since the gas supplied from below gradually rises together with the movable member, the gas-liquid contact time becomes long. Therefore, gas components are likely to dissolve in the culture solution.

  The stirring device of the present invention can include, for example, a fixing unit that fixes the movable member at a predetermined position. By doing so, for example, the movable member is fixed at a low position, and the gas held in the movable member can cover the periphery of a supply port (for example, an air diffuser) that supplies gas into the liquid. In that case, even after the gas release is stopped, the culture solution does not enter the gas supply port. The predetermined position is preferably a position that can cover the periphery of a supply port (for example, an air diffuser) that supplies gas into the liquid with the gas held by the movable member as described above.

The culture tank of the present invention includes the above-described stirring device. By providing such a stirrer, it is possible to stir with low power consumption and to prevent the precipitation of microorganisms.
Examples of the culture tank include a raceway type culture tank. A culture tank can be used for cultivation of microorganisms (for example, algae), for example.

  In the present invention, the upper limit position and the lower limit position may be the same position or different positions (for example, the upper limit position is higher than the lower limit position).

It is the figure which looked at the culture tank 3 provided with the stirring apparatus 1 from upper direction. It is a perspective view showing the structure of the stirring apparatus 1, (a) represents the case where the movable member 15 exists in the state A, (b) represents the case where the movable member 15 exists in the state B. It is sectional drawing in the cross section orthogonal to the axial direction of the movable member 15, (a) represents the case where the movable member 15 exists in the state A, (b) represents the case where the movable member 15 exists in the state B. It is explanatory drawing of the fixing device 39, (a) represents the state in which the fixing device 39 is not attached, (b) represents the state in which the fixing device 39 is attached. It is explanatory drawing of the movable part 41, (a) represents the state in which the movable part 41 is standing, (b) represents the state in which the movable part 41 was fallen. It is explanatory drawing showing the fixing structure using the volt | bolt 47, (a) represents the state which evacuated the volt | bolt 47, (b) represents the state which tightened the volt | bolt 47 to the back. It is a perspective view showing the structure of the guide rail attachment members 31, 33, 35, and 37. FIG. (A)-(e) is explanatory drawing showing operation | movement of the movable member 15. FIG. 3 is a perspective view illustrating a configuration of a stirring device 51. FIG. 6 is a cross-sectional view of a cross section orthogonal to the axial direction of the movable member 53. FIG. (A)-(e) is explanatory drawing showing operation | movement of the movable member 53. FIG.

Embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
1. Configuration of Stirrer 1 and Culture Tank 3 The configuration of the stirrer 1 and culture tank 3 will be described with reference to FIGS. FIG. 1 is a view of a culture tank 3 provided with a stirring device 1 as viewed from above. FIG. 2 is a perspective view illustrating the configuration of the stirring device 1. FIG. 3 is a cross-sectional view in a cross section orthogonal to the axial direction of the movable member 15 described later. 4-6 is explanatory drawing showing the fixing tool 39, the movable part 41, and the volt | bolt 47 which are mentioned later, respectively. FIG. 7 is a perspective view showing the configuration of guide rail mounting members 31, 33, 35, and 37 which will be described later.

  As shown in FIG. 1, the culture tank 3 is a well-known raceway type culture tank except for the stirring device 1. The culture tank 3 includes a flat-bottomed container 5 that is open at the top, a partition wall 7 that is erected at the center of the bottom surface, a paddle 9 that generates a flow in the culture solution in the flat-bottomed container 5, and a paddle 9 that is rotationally driven. And a motor 11 that performs. The culture tank 3 can be used for culture of microorganisms (for example, algae). The culture tank 3 is used with a predetermined amount of culture solution.

Moreover, the culture tank 3 is equipped with the stirring apparatus 1 in two places (near the both ends of the partition wall 7) where microorganisms precipitate easily, respectively. Furthermore, the culture tank 3 is provided with a diffuser tube 13 for blowing bubbles of air or CO ₂ gas (hereinafter simply referred to as gas) on the bottom surface of the flat bottom container 5 and below the stirring device 1. Yes. Gas is supplied to the air diffuser 13 from an external supply source (not shown) through the pipe 14.

  As shown in FIGS. 2 (a) and 2 (b), the stirring device 1 includes a movable member 15 and a straight bar-shaped guide rail (support means, state switching means) 17 erected on the bottom surface 5a of the flat bottom container 5. 19, 21, and 23. The guide rails 17, 19, 21, and 23 are similarly provided on both sides (the front side and the back side in FIG. 2) of the movable member 15, respectively.

  Each of the movable members 15 includes a first part 25 (unit member) and a second part (unit member) 27 each having a shape obtained by dividing a hollow cylinder into four parts. The first part 25 and the second part 27 are pivotally connected by a pivot shaft 29 at portions corresponding to the main parts of the fans on the end faces 25a and 27b. Therefore, the movable member 15 has a container shape in which the first part 25 and the second part 27 are combined with no gap as shown in FIGS. 2A and 3A and the hollow cylinder is divided into two as a whole. 2 and the state B in which a gap 28 is generated between the first part 25 and the second part 27 as shown in FIGS. 2B and 3B. . In the state A, as shown in FIG. 3A, the part on the first part 25 side of the circumferential surface 27 b of the second part 27 rides on the first part 25. As shown in FIGS. 2A and 2B, the movable member 15 is attached in such a direction that the rotating shaft 29 is on the lower side and the circumferential surfaces 25b and 27b are on the upper side, and the lower part thereof is open. .

  The movable member 15 is immersed in a culture solution put in a predetermined amount in the culture tank 3. In the state A, the movable member 15 can hold the gas supplied from the lower air diffuser 13 inside (lower side). When the amount of gas to be held becomes a predetermined amount or more, the buoyancy causes the movable member 15 to apply a force to rise in the culture solution. Moreover, the movable member 15 cannot hold | maintain gas in the case of the state B. FIG. When the movable member 15 holds the gas in the state A and then changes to the state B, the movable member 15 releases the held gas from the gap 28 between the first part 25 and the second part 27. When the amount of gas to be held becomes a predetermined amount or less, the movable member 15 is applied with a force to descend in the culture medium due to its weight.

  The first portion 25 of the movable member 15 includes guide rail mounting members 31 and 33 on the end surfaces 25a on both sides thereof. As shown in FIG. 7, the guide rail mounting members 31 and 33 are columnar members that protrude in the horizontal direction from the end face 25 a, and the vertical through holes 31 a and 33 a into which the guide rails 17 and 19 can be inserted are provided. Is provided. In the state shown in FIG. 2A, the position of the guide rail mounting member 31 is a position immediately above the rotation shaft 29 and in the vicinity of the circumferential surface 25b of the first portion 25. Further, the position of the guide rail mounting member 33 is substantially the same height as the rotation shaft 29 in the state shown in FIG. 2A, and is a position near the circumferential surface 25b. The guide rail attachment members 31 and 33 are attached to the first portion 25 so as to be rotatable in the arrow direction shown in FIG.

  By inserting the guide rails 17 and 19 into the through holes 31a and 33a, the first portion 25 is supported by the guide rails 17 and 19 so as to be movable in the vertical direction. The guide rails 17 and 19 are vertical in the axial direction, and the distance between them is constant. Therefore, when the first part 25 moves up and down in the vertical direction while being guided by the guide rails 17 and 19 in the culture solution, the direction (angle) of the first part 25 does not change. The guide rail attachment members 31 and 33 are similarly provided on the rear end face 25a in FIG. 2 and are connected in the same manner as the back guide rails 17 and 19.

  The second part 27 includes guide rail attachment members 35 and 37 on both end surfaces 27a. The guide rail mounting members 35 and 37 are the same as the guide rail mounting members 31 and 33, and are provided with vertical through holes 35a and 37a into which the guide rails 21 and 23 can be inserted (see FIG. 7). . In the state shown in FIG. 2A, the position of the guide rail mounting member 35 is a position immediately above the rotation shaft 29 and in the vicinity of the circumferential surface 27b of the second portion 27. Further, the position of the guide rail mounting member 35 is substantially the same height as the rotation shaft 29 in the state shown in FIG. 2A, and is a position in the vicinity of the circumferential surface 27b. The guide rail attachment members 35 and 37 are attached to the second portion 27 so as to be rotatable in the arrow direction shown in FIG.

  By inserting the guide rails 21 and 23 into the through holes 35a and 37a, the second portion 27 is supported by the guide rails 21 and 23 so as to be movable in the vertical direction. The guide rail 21 is inclined so that the distance from the guide rail 19 increases as it goes upward. Further, the guide rail 23 is inclined so that the distance from the guide rail 19 becomes narrower as it goes upward. The inclination of the guide rails 21 and 23 is for changing the direction (angle) of the second portion 27 as described later when the second portion 27 moves up and down. Note that the guide rail mounting members 35 and 37 are similarly provided on the rear end surface 27a in FIG. 2 and are connected in the same manner as the rear guide rails 21 and 23.

  As described above, the first part 25 is guided by the guide rails 17 and 19 and can move up and down in the culture medium, and the second part 27 is guided by the guide rails 21 and 23 and is in the culture medium. Therefore, the movable member 15 is guided by the guide rails 17, 19, 21, and 23 and can be moved up and down in the culture medium.

  A fixing device 39 can be attached to one or more of the guide rails 17, 19, 21, 23 as shown in FIG. The fixing device 39 is an annular rubber band and can be extrapolated to the guide rails 17, 19, 21, and 23. When the fixing device 39 is mounted on the upper side of the guide rail mounting members 31, 33, 35, 37 among the guide rails 17, 19, 21, 23, the guide rail mounting members 31, 33, 35, 37 are from the fixing device 39. Therefore, the upward movement of the movable member 15 can be stopped. The position of the fixing device 39 can be a position where the movable member 15 can be fixed at the lowermost position described later. As shown in FIG. 4A, the fixing device 39 can be removed from the guide rails 17, 19, 21, and 23. In this case, the upward movement of the movable member 15 is not limited.

  Instead of providing the fixing device 39, one or more of the guide rails 17, 19, 21, 23 may be provided with the movable portion 41 shown in FIG. The movable portion 41 is attached to a cutout portion 43 in which a part of the outer peripheral surface of the guide rails 17, 19, 21, 23 is cut out via a rotation shaft 45. The position of the rotation shaft 45 in the movable portion 41 is near one end in the longitudinal direction of the movable portion 41. As shown in FIG. 5A, if the longitudinal direction of the movable part 41 is the vertical direction, the guide rail mounting members 31, 33, 35, and 37 can pass through the movable part 41. The movement is not limited. On the other hand, as shown in FIG. 5B, in a state where the guide rail mounting members 31, 33, 35, and 37 are below the movable part 41, the movable part 41 is set so that the longitudinal direction of the movable part 41 becomes the horizontal direction. If 41 is tilted, the guide rail mounting members 31, 33, 35, and 37 cannot pass through the movable portion 41, and thus the upward movement of the movable member 15 is limited. The position of the movable part 41 can be a position where the movable member 15 can be fixed at the lowest position described later.

  Further, in place of or in addition to the fixing device 39 and the movable portion 41, one or more of the guide rail mounting members 31, 33, 35, and 37 are shown in FIGS. 6 (a) and 6 (b). Thus, the screw hole 49 into which the bolt 47 can be screwed may be provided. In this case, the guide rails 17, 19, 21, and 23 include a bolt hole 50 that can accommodate the tip of the screwed bolt 47. By screwing the bolt 47 into the screw hole 49 and pointing the tip of the bolt 47 into the bolt hole 50, the position of the guide rail mounting members 31, 33, 35, and 37 (that is, the movable member 15) is fixed. The position of the movable member 15 to be fixed can be set to the lowest position described later.

2. Operation of Stirring Device 1 The operation of the stirring device 1 will be described with reference to FIG. FIG. 8A shows that the state of the movable member 15 is the state A, and the position of the movable member 15 is guided by the guide rails 17, 19, 21, and 23 and can move up and down in the culture solution. This represents a state in which the amount of gas held at the movable member 15 is small at the lowest position (hereinafter referred to as the lowest position). The lowest position may be a position where the movable member 15 abuts against the bottom surface of the flat bottom container 5, or a guide rail mounting member 31 on a stopper (not shown) provided on the guide rails 17, 19, 21, 23. , 33, 35, and 37 may be in contact with each other. At this time, a downward force is applied to the movable member 15 due to its weight. When the movable member 15 is in the lowest position, the air diffuser 13 is accommodated in the movable member 15. That is, when the gas is sufficiently accumulated in the movable member 15 at the lowest position, the air diffuser 13 is in the gas.

  When the gas supplied by the air diffuser 13 gradually accumulates below the movable member 15 and the buoyancy of the gas exceeds the weight of the movable member 15, as shown in FIGS. The movable member 15 is guided by the guide rails 17, 19, 21, and 23 and moves up in the culture medium. At this time, the first portion 25 rises in the vertical direction without changing the direction (angle), but as the movable member 15 rises due to the inclination of the guide rails 21 and 23 as described above. The second part 27 rotates relative to the first part 25 in the direction of the arrow shown in FIGS. 2B and 3B, and the first part 25 and the second part 27 are overlapped. The portion (see FIG. 3A) decreases.

  Further, the movable member 15 rises and is guided by the guide rails 17, 19, 21, and 23 and can move up and down, and is the uppermost position and a position near the liquid level of the culture medium (hereinafter, the uppermost position). 8), a gap 28 is formed between the first portion 25 and the second portion 27 (that is, the movable member 15 enters the state B), and the lower portion of the movable member 15 is reached, as shown in FIG. The gas held on the side is released from the gap 28. When the amount of the retained gas becomes a predetermined amount or less, the weight of the movable member 15 becomes larger than the buoyancy of the gas, and the movable member 15 descends in the culture solution as shown in FIG. go. At this time, as the movable member 15 descends, the state of the movable member 15 gradually changes from the state B to the state A. And it returns to the state of Fig.8 (a).

  The movable member 15 periodically moves up and down between the lowest position and the highest position by periodically repeating the changes shown in FIGS. As a result, the culture solution in the culture tank 3 is agitated.

  When the movable member 15 is at the lowermost position, a fixing device 39 is attached to one or more of the guide rails 17, 19, 21, and 23 as shown in FIG. The position can be fixed at the lowest position. In this case, the movable member 15 does not rise, but gas accumulates inside (lower side) of the movable member 15, and the periphery of the air diffusion tube 13 is eventually covered with the gas held by the movable member 15.

3. Effects produced by the stirring device 1 (1) The stirring device 1 does not require a separate power source for driving the movable member 15 up and down. Further, unlike the prior art, it is not necessary to use ultrasonic waves. Therefore, the culture medium can be stirred with power saving.
(2) The stirring device 1 can fix the movable member 15 at the lowest position and cover the periphery of the air diffusion tube 13 with the gas accumulated inside (lower side). Therefore, even after the gas discharge from the air diffuser 13 is stopped, the liquid does not enter the air diffuser 13.
(3) Since the gas released from the air diffuser 13 rises slowly together with the movable member 15, the gas-liquid contact time becomes longer. Therefore, gas components are likely to dissolve in the culture solution.
<Second Embodiment>
1. Configuration of Stirring Device 51 The configuration of the stirring device 51 will be described with reference to FIGS. FIG. 9 is a perspective view showing the configuration of the stirring device 51. FIG. 10 is a cross-sectional view in a cross section orthogonal to the axial direction of the movable member 53 described later.

The stirring device 51 can be installed in place of the stirring device 1 in the culture tank 3 of the first embodiment. Under the stirring device 51, an air diffuser 13 for ejecting gas bubbles is provided.
As shown in FIG. 9, the stirring device 51 includes a movable member 53 and straight bar-shaped guide rails (supporting means) 55 and 57 erected on the bottom surface 5 a of the flat bottom container 5. The guide rails 55 and 57 are similarly provided on both sides (the front side and the back side in FIG. 9) of the movable member 53, respectively.

  The movable member 53 has a shape obtained by dividing a hollow cylinder into two parts, and is arranged so that an end surface 53a is a side surface and a circumferential surface 53b is an upper side. The movable member 53 includes an opening / closing valve 59 (state switching means) and an actuator (not shown) that drives the opening / closing valve 59 at the highest portion of the circumferential surface 53b.

  The movable member 53 is immersed in a culture solution placed in a predetermined amount in the culture tank 3. When the opening / closing valve 59 is closed, the movable member 53 can hold the gas supplied from the lower air diffuser 13 inside (lower side). When the amount of gas to be held becomes a predetermined amount or more, the buoyancy causes the movable member 53 to apply a force to rise in the culture solution. Further, when the opening / closing valve 59 is opened, the movable member 53 cannot hold the gas therein because the gas is released therefrom. When the opening / closing valve 59 is opened after the opening / closing valve 59 is opened after the opening / closing valve 59 is opened, the movable member 53 releases the held gas from the opening / closing valve 59. When the amount of gas to be held becomes a predetermined amount or less, the movable member 53 is applied with a force for lowering the culture medium due to its weight.

  The movable member 53 includes guide rail mounting members 61 and 63 on the end surfaces 53a on both sides thereof. The structure of the guide rail mounting members 61, 63 is the same as that of the guide rail mounting members 31, 33, 35, 37 in the first embodiment, and the vertical through holes 61a into which the guide rails 55, 57 can be inserted, respectively. 63a are provided. The positions of the guide rail mounting members 61 and 63 are near both ends in the left-right direction of the end surface 53a.

  By inserting the guide rails 55 and 57 into the through holes 61a and 63a, the movable member 53 is supported by the guide rails 55 and 57 so as to be movable in the vertical direction. The guide rails 55 and 57 have a vertical axial direction, and the distance between them is constant. Therefore, the movable member 53 is guided by the guide rails 55 and 57 and moves up and down in the vertical direction. The guide rail mounting members 61 and 63 are similarly provided on the rear end surface 53a in FIG. 9, and are connected in the same manner as the rear guide rails 55 and 57.

  A lowermost position sensor 65 is attached near the lower end of the guide rail 55, and an uppermost position sensor 67 is attached near the upper end of the guide rail 55. The lowest position sensor 65 is a sensor that senses the approach of the guide rail mounting member 61 when the movable member 53 is in the lowest position. That is, the lowest position sensor 65 is a sensor that detects that the movable member 53 is at the lowest position. When the lowest position sensor 65 detects that the movable member 53 is at the lowest position, the lowest position sensor 65 outputs a predetermined signal to the above-described actuator via a signal line (not shown). The actuator that has received the signal closes the open / close valve 59.

  The uppermost position sensor 67 is a sensor that senses the approach of the guide rail mounting member 61 when the movable member 53 is at the uppermost position. That is, the uppermost position sensor 67 is a sensor that detects that the movable member 53 is at the uppermost position. When the uppermost position sensor 67 detects that the movable member 53 is at the uppermost position, the uppermost position sensor 67 outputs a predetermined signal to the actuator described above via a signal line (not shown). The actuator that has received the signal opens the open / close valve 59.

2. Operation of Stirring Device 51 The operation of the stirring device 51 will be described with reference to FIG. In FIG. 11 (a), the opening / closing valve 59 is closed, and the position of the movable member 53 is the lowest position (hereinafter referred to as the following) in the range in which the position of the movable member 53 can be moved up and down in the culture medium guided by the guide rails 55 and 57 This represents a state where the amount of gas held by the movable member 53 is small. The lowermost position may be a position where the movable member 53 contacts the bottom surface of the flat bottom container 5, or may be a position where the guide rail mounting member 61 contacts the lowermost position sensor 65. At this time, a downward force is applied to the movable member 53 due to its weight. When the movable member 53 is in the lowest position, the air diffuser 13 is accommodated inside the movable member 53. That is, when the gas is sufficiently accumulated in the movable member 53 at the lowest position, the air diffuser 13 is in the gas.

  When the gas supplied by the air diffuser 13 gradually accumulates below the movable member 53 and the buoyancy of the gas exceeds the weight of the movable member 53, as shown in FIGS. The movable member 53 is guided by the guide rails 55 and 57 and moves up in the culture solution.

  When the movable member 53 further rises and reaches a position near the liquid level (hereinafter referred to as the uppermost position), the open / close valve 59 is opened based on the detection of the uppermost position sensor 67. Then, as shown in FIG. 12 (d), the gas held on the lower side of the movable member 15 is released from the opening / closing valve 59. When the amount of gas held is less than or equal to the predetermined amount, the weight of the movable member 53 becomes larger than the buoyancy of the gas, and the movable member 53 descends as shown in FIG. Then, the movable member 53 reaches the lowermost position, and the open / close valve 59 is closed based on the detection by the uppermost position sensor 67 to return to the state of FIG.

  The movable member 53 periodically repeats the changes in FIGS. 11A to 11E and moves up and down repeatedly between the lowest position and the highest position. As a result, the culture solution in the culture tank 3 is agitated.

  When the movable member 53 is in the lowest position, the fixing device 39 is attached to one or more of the guide rails 55 and 57 as shown in FIG. Can be fixed in position. In this case, the movable member 53 does not rise, but gas accumulates inside (lower side) of the movable member 53, and eventually, the periphery of the air diffusion tube 13 is covered with the gas held by the movable member 53.

3. Effects produced by the stirring device 51 (1) The stirring device 51 does not require a separate power source for driving the movable member 53 up and down. Further, unlike the prior art, it is not necessary to use ultrasonic waves. Therefore, the culture medium can be stirred with power saving.
(2) The stirring device 51 can fix the movable member 53 at the lowest position and cover the periphery of the air diffusion tube 13 with the gas accumulated inside (lower side). Therefore, even after the gas discharge from the air diffuser 13 is stopped, the liquid does not enter the air diffuser 13.
(3) Since the gas released from the air diffuser 13 rises slowly together with the movable member 53, the gas-liquid contact time becomes longer. Therefore, gas components are likely to dissolve in the culture solution.

In addition, this invention is not limited to the said embodiment at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.
For example, in the first embodiment, the shapes of the first part 25 and the second part 27 are not limited to those described above, and can hold the gas supplied from below in the state A. Can be arbitrarily selected. For example, the first part 25 and the second part 27 can be formed by dividing an arbitrary container shape having an opening at the bottom into two in an arbitrary manner.

  Further, in the first embodiment, the position where the state of the movable member 15 rising changes from the state A to the state B (or the position where the state of the movable member 15 falling changes from the state B to the state A. ) May be the uppermost position or a position lower by a predetermined amount than the uppermost position.

  In the first embodiment, the change in the positional relationship between the first part 25 and the second part 27 when shifting from the state A to the state B is not limited to that described above. For example, when the state A is shifted to the state B, the second part 27 may be slid away in a certain direction (eg, lateral direction, upward direction) as viewed from the first part 25. Such an operation can be realized by adjusting the shape and installation direction of the guide rails 17, 19, 21, and 23.

In the first embodiment, the moving direction of the movable member 15 is not limited to the vertical direction, and may be a direction inclined with respect to the vertical direction.
In the second embodiment, the shape of the movable member 53 is not limited to that described above, and can be arbitrarily selected as long as it can hold the gas supplied from below when the on-off valve 59 is closed. it can. For example, an arbitrarily shaped container having an opening at the bottom can be used as the movable member 53.

  In the second embodiment, the timing at which the opening / closing valve 59 is opened is not limited to the timing at which the movable member 53 has reached the uppermost position, but is the timing at which the movable member 53 has come to a position lower by a predetermined distance than the uppermost position. Alternatively, it may be a timing at which a predetermined time has elapsed since the movable member 53 reached the uppermost position.

  In the second embodiment, the timing for closing the opening / closing valve 59 is not limited to the timing when the movable member 53 comes to the lowest position, but the timing when the movable member 53 comes to a position higher by a predetermined distance than the lowest position. Alternatively, it may be a timing at which a predetermined time has elapsed since the movable member 53 has come to the lowest position.

  In the first and second embodiments, the air diffuser 13 may always supply gas at the same flow rate, and when the movable member 15 (53) is lowered, it rises. The flow rate of the gas may be reduced as compared to when the gas is being used. Further, when the movable member 15 (53) is lowered, the gas supply may be stopped.

DESCRIPTION OF SYMBOLS 1 ... Stirrer, 3 ... Culture tank, 5 ... Flat bottom container, 5a ... Bottom face,
7 ... partition wall, 9 ... paddle, 11 ... motor, 13 ... air diffuser,
15 ... movable member, 17, 19, 21, 23 ... guide rail, 28 ... gap,
25 ... 1st part, 25a ... End face, 25b ... Circumferential surface, 27 ... 2nd part,
27a ... end face, 27b ... circumferential surface, 29 ... rotating shaft,
31, 33, 35, 37 ... guide rail mounting members,
31a, 33a, 35a, 37a ... through hole, 39 ... fixing device,
41 ... movable part, 43 ... notch part, 45 ... rotating shaft, 47 ... bolt,
49 ... Screw hole, 50 ... Bolt hole, 51 ... Stirrer, 53 ... Movable member,
53a ... end face, 53b ... circumferential surface, 55, 57 ... guide rail,
59 ... Open / close valve, 61, 63 ... Guide rail mounting member,
61a, 63a ... through hole, 65 ... bottom position sensor, 67 ... top position sensor

Claims (5)

A movable member displaceable between a state A in which the gas supplied from below in the liquid can be held and a state B in which the held gas can be released to the outside;
Support means for supporting the movable member so as to be movable up and down;
When the position of the movable member in the vertical direction is above a predetermined upper limit position, the movable member is in the state B, and when the position of the movable member in the vertical direction is below a predetermined lower limit position, A state switching means for setting the movable member in the state A,
The movable member ascends or descends in the liquid according to the amount of gas held. The movable member is composed of a plurality of unit members whose mutual positional relationship is variable,
The state A is a state in which a hollow container shape capable of holding a gas supplied from below is formed by the plurality of unit members,
The state B is a state in which a gap for allowing gas to escape upward exists between the plurality of unit members,
The state switching means supports the plurality of unit members so as to be in the state B when the position of the movable member in the vertical direction is higher than the upper limit position, and positions the movable member in the vertical direction. 2. The stirring device according to claim 1, wherein the support unit is configured to support the plurality of unit members so as to be in the state A when the value is lower than the lower limit position. The movable member includes a gas holding unit capable of holding a gas supplied from below in the liquid, and a valve capable of releasing the gas held in the gas holding unit to the outside.
The state switching means opens the valve when the position of the movable member in the vertical direction is higher than the upper limit position, and when the position of the movable member in the vertical direction is lower than the lower limit position, The stirring device according to claim 1, wherein the valve is closed.   The stirrer according to any one of claims 1 to 3, further comprising fixing means for fixing the movable member at a predetermined position.   The culture tank provided with the stirring apparatus of any one of Claims 1-4.