Mixing device

Abstract

To provide an agitation device where a stirrer is swingingly rotated in an agitation vessel by applying a magnetic coupling transmitting rotating force without contacting and the function.SOLUTION: An agitator 10 comprises: an agitation tank with a vessel 5 formed with a planar bottom surface 7 and filled with a liquid 6 injected with a material to be agitated; and an agitation device 100 with a drive part 150 rotating a stirrer 110 arranged in the vessel 5 and a stirrer 110 at the outside of the vessel 5. The stirrer 110 realizes revolution and rotation in the vessel 5 of the agitation tank without contacting. In the constituted agitation device 100, the material to be agitated is mixed with centrifugal force caused by revolution and shear stress caused by rotation and then uniform agitation can be performed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a magnetic coupling that transmits rotational force in a non-contact manner and to a stirring device to which the magnetic coupling is applied. [Background technology]

[0002] When stirring a liquid in a stirring vessel, it is necessary to avoid as much as possible the introduction of impurities caused by friction, wear, and lubrication when rotating the stirring blades inside the vessel, and to prevent damage to cells, etc. Therefore, a stirring technology has been disclosed in which power is transmitted from outside the vessel in a non-contact manner to rotate the stirrer.

[0003] By transmitting power to the stirrer in a non-contact manner, the stirrer can rotate inside the mixing vessel without touching the inner wall of the vessel. This has the advantage of eliminating the risk of damage to the stirred material due to friction and wear at the contact point between the stirring part and the vessel, and eliminating the risk of impurities being mixed in.

[0004] As a device for rotating such a stirrer without contact to stir the liquid stored inside the stirring tank, there is a device that uses a magnetic coupling between the stirring blade (rotated body) arranged inside the stirring tank and the output shaft (rotating body) of a drive unit such as a motor arranged outside the stirring tank, so that the rotational force of the drive unit is transmitted to the stirring blade without contact (see, for example, Patent Documents 1 and 2).

[0005] In this type of magnetic coupling, an attracting magnet unit and a repelling magnet unit are arranged at the opposing positions of the agitator blade and the output shaft of the drive unit, and the repulsive force of the repelling magnet unit keeps the agitator blade suspended inside the agitator tank, while the attractive force of the attracting magnet unit transmits rotational force without contact.

[0006] Meanwhile, a technique has been disclosed in which a stirrer having both a magnetic levitation function and a magnetic coupling function due to a superconducting bulk body is used to levitate and rotate the stirrer (see Patent Document 3). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-035098 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-013216 [Patent Document 3] Japanese Patent Application Laid-Open No. 2009-148709 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the technologies disclosed in Patent Documents 1 and 2 require delicate control of magnetic force, distance, etc., in order to transmit power for rotating the stirrer while adjusting the magnetic force of the magnetic coupling and to prevent the stirrer from contacting the stirring vessel. For example, in Patent Document 1, after the mutual distance along the axis between the stirring blade and the output shaft increases, there is no longer any force acting to bring them closer together, and the mutual distance continues to increase, which may make it difficult to transmit the rotational force.

[0009] Patent Document 2 discloses a magnetic coupling and stirring device that can continuously transmit power without contact even when the axial distance between the rotated body and the rotating body increases, as in Patent Document 1. However, this technology requires the magnetic forces of the repulsive magnet unit to exceed the attractive force of the attracting magnet unit when the axial distance between the rotating body and the rotated body is smaller than a preset threshold, and to be set so that the attractive force of the attracting magnet unit exceeds the repulsive force of the repulsive magnet unit when the axial distance increases beyond the threshold, necessitating delicate adjustment of the magnet units.

[0010] Furthermore, the technology of the non-contact stirring device disclosed in Patent Document 3 places a power source outside the stirring tank, and magnetically levitates and rotates stirring blades made of bulk superconductors inside the tank. Although this produces the expected effects, there is a possibility that the costs for materials and equipment will be high.

[0011] Furthermore, in the technologies disclosed in Patent Documents 1, 2, and 3, the rotation axis of the agitator is aligned with the output shaft installed outside the agitation vessel. However, since the liquid in the vessel can be mixed better by agitating the entire agitation vessel than by a fixed rotation shaft, it is preferable that the agitator rotates and oscillates.

[0012] The present invention has been made in consideration of the above-mentioned circumstances, and its object is to provide a magnetic coupling that transmits rotational force without contact, without relying on magnetic coupling that requires the magnetic force of a superconducting bulk body or a complex magnet unit, and a stirring device that applies this function to rotate a stirring bar in an oscillatory manner within a stirring tank. [Means for solving the problem]

[0013] The present invention provides a stirring device comprising a stirrer having a flat bottom surface and disposed in a container filled with liquid, and a drive unit that rotates the stirrer outside the container. The stirrer, which is one aspect of the present invention, comprises a rotation axis extending perpendicular to the bottom surface, a driven magnet unit that extends radially from the rotation axis at one end of the rotation axis on the bottom surface side, parallel to the bottom surface, with the circumference of a concentric circle for rotation centered on the rotation axis as its outer edge, and includes a plurality of first magnets disposed at intervals in the circumferential direction of the concentric circle for rotation, and a watertight float that is provided on the other end of the rotation axis and floats the stirrer to the liquid surface. The drive unit is: The stirring member is formed in a disk shape and has a revolution axis at the center of the disk, which serves as a rotation axis for revolving the stirring member. A plurality of second magnets, which rotate around the revolution axis so as to face the bottom surface, extend radially from the revolution axis with the circumference of the concentric circle for revolution centered on the revolution axis as an outer edge, and are arranged at intervals in the circumferential direction of the concentric circle for revolution, and have polarities opposite to those of the first magnets. TakakuThe float is configured to have a rotating magnet section and a rotation drive device that rotates the driving magnet section, and the diameter of the rotation concentric circle is different from the diameter of the revolution concentric circle, and the buoyancy of the float is adjusted so that the driven magnet section does not contact the bottom surface of the container.

[0014] In this configuration, the stirrer is suspended in the agitation vessel by the buoyancy of the float provided on the stirrer itself in the agitation vessel and the magnetic force between the magnet provided on the bottom of the agitation vessel and the magnet provided in the drive unit at the bottom of the agitation vessel, and the position of the stirrer is regulated by magnetic coupling. Furthermore, by making the sizes of the concentric circles for revolution of the drive unit and the concentric circles for rotation of the stirrer different, the rotation axis of the stirrer can rotate on the concentric circles for revolution. Furthermore, when the drive magnet unit of the drive unit is rotated, the second magnet provided in the drive magnet unit attracts the first magnet of the stirrer, causing the stirrer to begin orbital motion and rotate on its axis. The revolving stirrer rotates in the opposite direction to the direction of revolution due to the resistance of the liquid around the stirrer. Thus, with this configuration, the agitator can be made to perform so-called planetary motion within the agitation vessel.

[0015] This configuration allows the agitator to revolve and rotate without contacting the inside of the agitator vessel. In other words, this configuration allows the agitator to mix and uniformly agitate the materials being agitated by utilizing the centrifugal force generated by the agitation and the shear stress generated by the agitation. Furthermore, the rotational direction of the agitator and the agitation can be changed simply by switching the direction of rotation of the motor during agitation. Furthermore, by achieving planetary motion without contact, the risk of damage due to friction and wear at the contact point between the agitator and the vessel and the risk of impurities being mixed into the agitated material can be prevented. Compared to Patent Documents 1, 2, and 3, this configuration is simpler and easier to adjust, resulting in reduced costs and improved productivity through adjustment and regulation.

[0016] Another aspect of the present invention is a stirring device comprising a stirring bar disposed in a container having a flat bottom surface and filled with a liquid, and a drive unit outside the container for rotating the stirring bar. The stirring bar in one aspect of the present invention has a rotation axis extending perpendicular to the bottom surface, and at one end of the rotation axis on the bottom surface side, radially extending from the rotation axis with the circumference of a concentric circle for rotation centered on the rotation axis as an outer edge, and spaced apart in the circumferential direction of the concentric circle for rotation. Te2 one very a driven magnet section in which a third magnet, which is a plurality of multi-pole magnets having a property of being oriented, is arranged; and a driven magnet section is provided on the other end side of the rotation shaft, and the third magnet floats the stirring bar to the liquid surface. Rufu and a funnel. The stirring member is formed in a disk shape, and has a revolution axis at the center of the disk, which serves as a rotation axis for revolving the stirring member. a plurality of fourth magnets that rotate around the revolution axis so as to face the bottom surface, extend radially from the revolution axis with the circumference of the concentric circle for revolution centered on the revolution axis as an outer edge, and are spaced apart in the circumferential direction of the concentric circle for revolution; very A plurality of fifth magnets of different properties are arranged alternately at intervals. Takaku The magnet assembly includes a driving magnet unit and a rotation drive device that drives the driving magnet unit to rotate. The diameter of the concentric circle for rotation is different from the diameter of the concentric circle for revolution, and the buoyancy of the float is adjusted so that the driven magnet unit does not contact the bottom surface of the container.

[0017] In this configuration, the buoyancy of the stirrer's float within the mixing vessel and the magnetic attraction between a magnet attached to the bottom of the mixing vessel (below the stirrer) and a magnet attached to the drive unit (located at the bottom of the mixing vessel) keep the stirrer suspended within the mixing vessel and regulate its position. By differentiating the sizes of the concentric circles for revolution in the drive unit and the concentric circles for rotation of the stirrer, the rotation axis of the stirrer can rotate on the concentric circles for revolution. Furthermore, when the drive magnet unit of the drive unit is rotated, the fourth and fifth magnets arranged at intervals in the drive magnet unit and the multiple multi-pole magnets arranged at intervals in the driven magnet unit begin orbital motion in the direction opposite to the rotation of the drive magnet, from a state in which the stirrer is attracted to the magnets opposite to the drive magnet unit's respective polarities before revolution begins. The orbital motion of the stirrer rotates in the same direction or opposite to the direction of revolution due to the resistance of the liquid around the stirrer. As the stirrer rotates, magnetic coupling between the third magnet and the fourth and fifth magnets causes repeated attraction and repulsion, increasing the rotational speed of the stirrer. Thus, with this configuration, the stirrer can perform so-called planetary motion within the stirring vessel.

[0018] According to the above configuration, the stirrer can achieve revolution and rotation without contacting the inside of the stirring vessel. In other words, this configuration allows the stirring device to mix and uniformly stir the material being stirred by the centrifugal force generated by the revolution and the shear stress generated by the rotation. The rotation speed of the stirrer can be adjusted by adjusting the arrangement of the third, fourth, and fifth magnets. Furthermore, realizing planetary motion without contact prevents impurities from being mixed into the material being stirred due to friction and wear that occurs at the contact point between the stirring part and the vessel. Furthermore, compared to Patent Documents 1, 2, and 3, this configuration is simpler and easier to adjust, reducing costs and improving productivity through adjustment and regulation. Furthermore, by carefully adjusting the arrangement of the third, fourth, and fifth magnets, the rotation speed can be adjusted to achieve stirring appropriate for the material being stirred.

[0019] In the above configuration, the third magnets adjacent to each other with a gap therebetween are veryIt can be configured so that the genders are the same.

[0020] The above configuration is such that the third magnets adjacent to each other are spaced apart and face each other. very By keeping the same properties, the area of ​​the gap is wider and stronger than that of a single magnet. very As the stirrer rotates, this magnetic field is magnetically coupled with the fourth and fifth magnets, causing repeated attraction and repulsion, increasing the rotational speed of the stirrer.

[0021] With this configuration, the magnetic field is wider and stronger than that of a single third magnet, so stable magnetic coupling can be maintained despite transient state changes such as attraction and repulsion due to magnetic coupling, and the positional relationship between the stirrer and the drive magnet unit. Therefore, this configuration prevents the stirrer from leaving its orbital path, increases the rotational speed of the stirrer and the revolution, and improves the stirring capacity.

[0022] In the stirring device of the above aspect, the diameter of the concentric circles for rotation may be smaller than the diameter of the concentric circles for revolution.

[0023] According to the above configuration, by making the concentric circle for revolution larger than the concentric circle for rotation, it is possible to prevent the stirrer from deviating from the orbit of the concentric circle for revolution and swinging toward the side of the agitation vessel. This configuration is suitable for avoiding the risk of contact with the side when the size of the agitation vessel does not allow for the swinging range of the stirrer. Needless to say, even if the concentric circle for revolution is smaller than the concentric circle for rotation, the stirring function can be achieved by adjusting the magnetic force between the driving magnet unit and the driven magnet unit. This is effective when the size of the agitation vessel is large relative to the swinging motion of the stirrer, and it is also possible to configure a agitation vessel equipped with multiple agitation devices according to this configuration.

[0024] In the stirring device of the above aspect, the rotation shaft is provided with one or more For stirring liquids The blades may be attached.

[0025] Friction between the agitator and the surrounding liquid (stirred material) alone creates little fluid resistance. With this configuration, adding blades to the agitator's rotation axis improves mixing performance and promotes the agitator's rotation. The blades can be attached to the outside of the agitator's rotation axis (radial direction of the rotation axis), or on the top or bottom. For example, blades can be added to the outside by attaching radial turbine-type blades to the top or bottom of the rotating shell. Also, by attaching the blades in symmetrical positions, balance can be achieved when the agitator rotates.

[0026] Although the configuration becomes somewhat more complicated, by equipping the stirrer with communication, control, and drive devices and adjusting the angle of the blades from outside, it is possible to make the stirrer float or sink within the mixing vessel, or change the oscillation range.

[0027] In the stirring device of the above aspect, the float can be configured to be able to move up and down along the rotation axis.

[0028] According to the above configuration, even if the liquid level of the material to be stirred filled in the stirring tank changes, the position of the stirrer can be adjusted by adjusting the float position so that it does not come into contact with the bottom surface of the stirring tank.

[0029] In the stirring device of the above aspect, the float may be filled with a liquid or gas corresponding to the liquid.

[0030] According to the above-mentioned configuration, it is possible to fill or inject gas or liquid into the float according to the required buoyancy in accordance with the material to be stirred, without changing the size of the float. [Effects of the Invention]

[0031] The present invention can provide a magnetic coupling that transmits rotational force without contact, without relying on magnetic couplings that require the magnetic force of superconducting bulk materials or complex magnet units, and a stirring device that uses this to rotate a stirrer in an oscillatory manner.

[0032] Currently, there is a growing demand for agitation devices for uniformly mixing materials such as cell culture. For cell culture, it is desirable to slowly agitate the entire material without applying shear stress to the cells. Furthermore, to prevent the incorporation of foreign matter, there is a need for devices that are free from friction and wear and are completely sealed from the outside. The agitation device of the present invention can provide a stirring action that meets these requirements. [Brief explanation of the drawings]

[0033] [Figure 1] 1 is an overall explanatory side cross-sectional view of a stirring device according to a first embodiment of the present invention. [Figure 2] FIG. 1 is an explanatory diagram showing a side cross section of one aspect of a stirring bar according to a first embodiment of the present invention. [Figure 3] FIG. 2 is a plan view of a driven magnet portion according to the first embodiment of the present invention. [Figure 4] FIG. 2 is a plan view of a drive magnet section according to the first embodiment of the present invention. [Figure 5] FIG. 2 is an explanatory diagram of the operation of the stirring bar according to the first embodiment of the present invention. [Figure 6] FIG. 10 is a plan view of a driven magnet portion according to a second embodiment of the present invention. [Figure 7] FIG. 10 is a plan view of a drive magnet section according to a second embodiment of the present invention. [Figure 8] FIG. 10 is an explanatory diagram of the operation of the stirring bar according to the second embodiment of the present invention. [Figure 9] FIG. 10 is a plan view of a driven magnet portion according to a third embodiment of the present invention. [Figure 10] FIG. 10 is an explanatory diagram of the operation of the stirring bar according to the third embodiment of the present invention. [Figure 11] FIG. 10 is an explanatory diagram of a stirring bar according to a fourth embodiment of the present invention. [Figure 12]FIG. 1 is an explanatory diagram of a stirring bar according to an embodiment of the present invention. [Figure 13] 1 is an image captured from a video of the operation of one embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0034] Hereinafter, with reference to the drawings, a preferred embodiment of a magnetic coupling for transmitting rotational force in a non-contact manner and a stirring device to which the same is applied will be described. In the following description, components with the same reference numerals in different drawings are considered to be similar, and their description may be omitted.

[0035] In one aspect of the present invention, a stirring device is provided with a stirring bar having a flat bottom surface and disposed in a container filled with liquid, and a drive unit that rotates the stirring bar outside the container. The stirring bar has a rotation axis that extends perpendicular to the bottom surface, and a driven magnet unit that extends radially from the rotation axis at one end of the rotation axis on the bottom surface side, parallel to the bottom surface, with the circumference of a concentric circle for rotation centered on the rotation axis as an outer edge, and has a plurality of first magnets arranged at intervals in the circumferential direction of the concentric circle for rotation; and a driven magnet unit that is provided on the other end of the rotation axis and that floats the stirring bar to the liquid surface. Rufu The drive unit includes: The stirring bar is formed in a disk shape, and a stirring bar revolution shaft is provided at the center of the disk as a rotation shaft and as a rotation shaft for revolving the stirring bar. a plurality of fourth magnets that rotate around the revolution axis so as to face the bottom surface, extend radially from the revolution axis with the circumference of the concentric circle for revolution centered on the revolution axis as an outer edge, and are spaced apart in the circumferential direction of the concentric circle for revolution; very A plurality of fifth magnets of different properties are arranged alternately at intervals. Takaku The float may be configured in any specific form as long as it includes a driving magnet unit and a rotation drive device that rotates the driving magnet unit, the diameter of the concentric circle for rotation is different from the diameter of the concentric circle for revolution, and the buoyancy of the float is adjusted so that the driven magnet unit does not contact the bottom surface of the container.

[0036] In another aspect of the present invention, in a stirring device including a stirring bar having a flat bottom surface formed therein and disposed in a container filled with liquid, and a drive unit for rotating the stirring bar outside the container, the stirring bar has a rotation axis extending perpendicular to the bottom surface, and at one end of the rotation axis on the bottom surface side, a circumference of a concentric circle for rotation centered on the rotation axis is used as an outer edge, extending radially from the rotation axis and spaced apart in the circumferential direction of the concentric circle for rotation so as to be parallel to the bottom surface. Te2 one very a driven magnet section in which a third magnet is arranged, the third magnet being a plurality of multi-pole magnets having a property; The stirring bar is provided on the other end of the rotating shaft and floats up to the liquid surface. Rufu The drive unit includes: The stirring member is formed in a disk shape, and has a revolution axis at the center of the disk, which serves as a rotation axis for revolving the stirring member. a plurality of fourth magnets that rotate around the revolution axis so as to face the bottom surface, extend radially from the revolution axis with the circumference of the concentric circle for revolution centered on the revolution axis as an outer edge, and are spaced apart in the circumferential direction of the concentric circle for revolution; very A plurality of fifth magnets of different properties are arranged alternately at intervals. Takaku a dynamic magnet section; and a rotation drive device that drives the drive magnet portion to rotate. The specific configuration of the stirring device may be any configuration as long as the diameter of the rotation concentric circle is different from the diameter of the revolution concentric circle, and the buoyancy of the float is adjusted so that the driven magnet portion does not contact the bottom surface of the container.

[0037] (Description of the First Embodiment) First, one embodiment of the present invention will be described with reference to Figures 1 to 5. Figure 1 is an overall explanatory diagram showing a side cross section of a stirring device according to a first embodiment of the present invention. Figure 2 is an explanatory diagram showing a side cross section of one aspect of a stirring bar according to a first embodiment of the present invention. Figure 3 is a plan view of a driven magnet section according to a first embodiment of the present invention. Figure 4 is a plan view of a driving magnet section according to a first embodiment of the present invention. Figure 5 is an explanatory diagram of the operation of a stirring bar according to a first embodiment of the present invention.

[0038] 1 to 4, this embodiment is an agitator 10 comprising a stirring tank having a container 5 formed with a flat bottom surface 7 and filled with a liquid 6 containing a material to be stirred, and an agitator 100 having a stirring bar 110 disposed in the container 5 and a drive unit 150 outside the container 5 for rotating the stirring bar 110.

[0039] The shape of the vessel 5 serving as the stirring vessel can be cylindrical, rectangular, or cubic, and this embodiment can be applied as long as it has a flat bottom surface 7 within the range where the stirring device 100 can be installed. In addition, as for the material of the vessel 5, a general stirring vessel can be applied as long as it is non-magnetic (a material that is not attracted to a magnet).

[0040] The agitator 110 is provided with a rotation axis 130 extending perpendicularly to the bottom surface 7, a driven magnet section 120 which extends radially from the rotation axis 130 at one end of the rotation axis 130 on the bottom surface 7 side, parallel to the bottom surface 7, with the circumference of a concentric circle for rotation 125 centered on the rotation axis 130 as its outer edge, and in which a plurality of first magnets 122 are arranged at intervals in the circumferential direction of the concentric circle for rotation 125, and a watertight float 140 which is provided on the other end side of the rotation axis 130 and floats the agitator 110 to the liquid surface.

[0041] There are no particular restrictions on the material or shape of the rotating shaft 130, driven magnet portion 120, and float 140 that make up the stirring bar 110, as long as they do not have any adverse effects, such as melting the stirred material into the mixed liquid 6.

[0042] The driven magnet section 120 is fixed to the rotation shaft 130, and may have a disk-like shape with the first magnet 122 arranged therein as shown in Fig. 3, or may have a plate-like shape with only the first magnet 122 arranged therein, such that the first magnet 122 is arranged in the direction of the tip of an arm-like shape extending radially from the rotation shaft 130 as shown in Fig. 10 of an embodiment described later. Note that whether the driven magnet section 120 is disk-like or arm-like, it is configured so that the circumference of the rotation concentric circle 125 forms the outer edge. Furthermore, the number of first magnets 122 arranged is not limited as long as magnetic coupling for revolution is achieved, but a configuration with at least two magnets arranged diagonally is preferred.

[0043] The multiple first magnets 122 may have polarity opposite to that of the second magnets 162, and as an example, in Figure 3 they are arranged so that the north pole of the north-south poles faces in a plan view. As for the number of multiple first magnets 122, it is preferable to arrange them at equal angular intervals to achieve predictable rotational motion, but they may also be arranged at different intervals to intentionally cause irregular oscillation.

[0044] As shown in Figure 1, the buoyancy FB of the float 140 is adjusted based on the relationship between the total length HL of the stirring bar 110 and the liquid depth HB, relative to the attractive forces FMD and FMU due to the magnetic coupling so that the driven magnet part 120 does not come into contact with the bottom surface 7 of the container 5.

[0045] As described above, this embodiment does not require the complicated adjustment of the floating position and the transmission of the rotational driving force by the magnetic coupling as in Patent Documents 1 to 3. In other words, the float 140 only needs to float the stirring bar 110 itself and adjust the buoyancy FB to counteract the attractive forces FMD and FMU caused by the magnetic coupling.

[0046] For example, if the container 5 is empty and the stirring bar 110 is placed on the bottom surface 7 of the container 5, and the non-stirring material and solution are poured into the container 5, when the amount of solution reaches the liquid depth HB, the stirring bar 110 will float in the liquid 6 due to the buoyancy FB of the float 140. After that, when the distance between the driven magnet part 120 and the bottom surface 7 reaches a predetermined distance in accordance with the revolution and rotation during stirring, stirring can begin.

[0047] The buoyancy FB can be adjusted by filling the float 140 with a liquid or gas according to the specific gravity of the liquid 6. With this configuration, the float 140 can be filled or injected with gas or liquid according to the required buoyancy, depending on the material to be stirred, without changing the size of the float 140.

[0048] Although the shape of the float 140 is a truncated cone in FIGS. 1 and 2, it may be a cylinder, a disk, or an inverted truncated cone, and the shape is not particularly limited.

[0049] 2, a configuration may be adopted in which a blade 145 is provided between the float 140 and the driven magnet portion 120. There are no particular limitations on the material of the blade 145, as long as it does not have an adverse effect on the liquid 6, such as melting the material to be stirred.

[0050] The blades 145 can promote the rotation by increasing the resistance received from the liquid when the stirring bar 110 starts to revolve. The shape of the blades 145 can be set according to the rotation and the degree of stirring, and is not particularly limited.

[0051] The drive unit 150 faces the bottom surface 7. It serves as the rotation axis for the revolution of the stirring bar 110 The drive magnet section 160 is rotated around the revolution axis 170. The drive magnet section 160 is provided with a plurality of second magnets 162 that extend radially from the revolution axis 170 with the circumference of a concentric circle for revolution 165 centered on the revolution axis 170 as its outer edge, and that are spaced apart in the circumferential direction of the concentric circle for revolution 165, and that have opposite polarities to the first magnets 122. The drive magnet section 160 is rotationally driven by a motor 180, which is a rotation drive device.

[0052] The drive magnet unit 160 is fixed to the revolution shaft 170, and as shown in Fig. 4, the second magnet 162 may be arranged in a disk-like shape, or may be in the form of a plate that only includes the second magnet 162, with the second magnet 162 arranged in an arm-like shape that extends radially from the revolution shaft 170 and the second magnet 162 arranged toward the tip of the arm-like shape. Whether the drive magnet unit 160 is disk-shaped or arm-shaped, it is sufficient that it is configured so that the circumference of the concentric circle for revolution 165 forms its outer edge. The number of second magnets 162 to be arranged is not limited as long as magnetic coupling for revolution is achieved, but a configuration with at least two magnets arranged diagonally is preferred.

[0053] The second magnets 162 may have any polarity that is opposite to that of the first magnets 122, and in Fig. 4, as an example, they are arranged so that their south poles face in a plan view. As for the number of second magnets 162, it is preferable to arrange them at equal angular intervals to achieve predictable rotational motion, but they may also be arranged at different intervals to intentionally cause irregular oscillation.

[0054] The revolution and rotation of the stirring bar 110 will be described with reference to Figure 5. Figure 5 shows the stirring bar 110 and drive unit 150 arranged in the state shown in Figure 1, as viewed from above.

[0055] The driving magnet unit 160 is driven by the motor 180 to make an orbital rotation RB about the revolution axis 170. Since the first magnet 122 of the stirring bar 110 and the second magnet 162 of the driving unit 150 are magnetically coupled, the stirring bar 110 starts to make an orbital rotation RB along the revolution orbit 175.

[0056] Due to the revolution RB, the stirring bar 110 experiences resistance from the liquid 6. At this time, because the rotation axis 130 and the revolution axis 170 are eccentric, a force acts on the stirring bar 110 in the opposite direction to the rotation direction of the revolution RB, and the stirring bar 110 starts to rotate on its own axis RF.

[0057] The revolution orbit 175 of the stirring bar 110 is determined by the concentric circle 125 for rotation of the driven magnet section 120 on which the first magnet 122 is arranged and the concentric circle 165 for revolution of the driving magnet section 160 on which the second magnet 162 is arranged.

[0058] According to this embodiment, the stirring bar 110 can be made to revolve and rotate without contacting the inside of the stirring tank, which is the container 5. That is, the stirring device 100 having this configuration can mix the material to be stirred and perform uniform stirring by the centrifugal force generated by the revolution and the shear stress caused by the rotation.

[0059] Furthermore, by realizing non-contact planetary motion, it is possible to prevent impurities from being mixed into the object being stirred due to friction and wear that occurs at the contact points between the stirring device 100 and the container 5. Furthermore, compared to conventional technology, this configuration is simpler and easier to adjust, reducing costs and improving productivity through adjustment and regulation.

[0060] (Description of the second embodiment) Next, a second embodiment of the present invention will be described with reference to Figs. 1, 2, and 6 to 8. Fig. 6 is a plan view of a driven magnet section according to the second embodiment of the present invention. Fig. 7 is a plan view of a driving magnet section according to the second embodiment of the present invention. Fig. 8 is an explanatory diagram of the operation of a stirrer according to the second embodiment of the present invention. In the following description, explanations of configurations similar to those of the first embodiment will be omitted, and only configurations that differ will be described.

[0061] 1, 2, and 6, the stirring bar 210 of the stirring device 200 according to the second embodiment comprises a rotation axis 230 extending perpendicularly to the bottom surface 7, and a pair of concentric circles 225 for rotation 225, which are arranged at one end of the rotation axis 230 on the bottom surface 7 side, and extend radially from the rotation axis 230 with the circumference of the concentric circle 225 for rotation as the outer edge, and spaced apart from each other in the circumferential direction of the concentric circle 225 for rotation, so as to be parallel to the bottom surface 7. Te2 one very The driven magnet section 220 is provided with third magnets 222, 224, which are multiple multi-pole magnets having a magnetic field, and a watertight float 140 is provided on the other end side of the rotation axis 230 and floats the stirring bar 210 to the liquid surface.

[0062] 7, the drive unit 250 rotates around the revolution axis 270 so as to face the bottom surface 7, and has a plurality of fourth magnets 266 and 266a, which extend radially from the revolution axis 270 with the circumference of a concentric circle for revolution 272 centered on the revolution axis 270 as its outer edge, and are spaced apart in the circumferential direction of the concentric circle for revolution 272. very The apparatus includes a disk-shaped drive magnet section 260 in which a plurality of fifth magnets 264 of different properties are alternately arranged at intervals, and a motor 180 that drives the drive magnet section 260 to rotate.

[0063] The diameter of the rotation concentric circle 225 is smaller than the diameter of the revolution concentric circle 272, and the buoyancy of the float 140 is adjusted so that the driven magnet portion 220 does not come into contact with the bottom surface 7 of the container 5.

[0064] The revolution and rotation of the stirring bar 210 will be described with reference to Fig. 8. Fig. 7 assumes that the stirring bar 210 and the drive unit 250 are arranged in the state shown in Fig. 1.

[0065] Drive magnet unit 260 is driven by motor 180 to make an orbital rotation RB about revolution axis 270. Because third magnets 222, 224 of stirrer 210 and either fourth magnet 266 or fifth magnet 264 of drive unit 250 are magnetically coupled, stirrer 210 begins to make an orbital rotation RB along revolution orbit 275.

[0066] Due to the revolution RB, the stirring bar 210 experiences resistance from the liquid 6. At this time, because the rotation axis 230 and the revolution axis 270 are eccentric, a force acts on the stirring bar 210 in the opposite direction to the rotation direction of the revolution RB, and the stirring bar 210 starts to rotate on its own axis RS.

[0067] The orbital path 275 of the stirring bar 210 is determined by the concentric circle 225 for rotation of the driven magnet section 220 on which the third magnets 222, 224 are arranged, and the concentric circle 265 for revolution of the driving magnet section 260 on which the fourth magnet 266 and the fifth magnet 264 are arranged.

[0068] Furthermore, in the second embodiment, as shown in Figures 8(A), (B), and (C), in addition to rotation due to the resistance of the liquid 6, attractive forces due to magnetic coupling between the third magnet 222 and the fourth magnet 266 and the fifth magnet 264 and repulsive forces due to rotational misalignment occur alternately.

[0069] The mechanism will be explained in detail. The buoyancy FB caused by the float 140 of the stirrer 210 itself in the stirring tank, which is the container 5, and the magnetic force generated by the attraction between the magnet provided on the stirrer 210 on the bottom surface 7 side of the stirring tank and the fourth magnet 266 or the fifth magnet 264 provided on the drive unit 250 provided on the bottom surface of the stirring tank, keep the stirrer 210 floating in the container 5 and regulate the position of the stirrer 210.

[0070] By making the sizes of the concentric circle for revolution 272 of the drive unit 250 and the concentric circle for rotation 225 of the stirrer 210 different, the rotation axis 230 of the stirrer 210 can rotate in planetary motion on the revolution orbit 275. Furthermore, when the drive magnet unit 260 of the drive unit 250 is rotated, the fourth magnet 266 and the fifth magnet 264 arranged at intervals in the drive magnet unit 260 and the third magnets 222, 224 which are multiple multi-pole magnets arranged at intervals in the driven magnet unit 220 start to revolve as the drive magnet unit 260 rotates, from a state in which the stirrer 210 is attracted to the magnets that are opposite poles to the drive magnet unit 260 before the start of revolution.

[0071] Thereafter, the stirring bar 210 undergoes an orbital motion and rotates in the direction opposite to the direction of revolution due to the resistance of the liquid 6 around the stirring bar 210. As the stirring bar 210 rotates, magnetic coupling between the third magnet 224 and the fourth magnet 266 and the fifth magnet 264 repeatedly attracts and repels the third magnet 224, as shown in (A) to (C) of FIG. 8, increasing the rotational speed of the stirring bar 210. As described above, according to this embodiment, the stirring bar 210 can be caused to perform planetary motion within the stirring vessel, and the rotational speed can be increased or decreased. The relationship between the direction of revolution and the direction of rotation can be changed by having the center of the rotation concentric circle 225 pass through the inner or outer side of the orbital path 275, and can also be changed by the relationship between forces such as the initial rotation and the water resistance of the blades.

[0072] In this way, in the second embodiment, the rotation speed RS can be controlled by utilizing magnetic coupling in accordance with the non-stirring material, compared to the rotation speed RF that is controlled solely by the resistance of the liquid in the first embodiment.

[0073] (Description of the third embodiment) Next, a third embodiment of the present invention will be described with reference to Figures 9 and 10. Figure 9 is a plan view of a driven magnet part according to the third embodiment of the present invention. Figure 10 is an explanatory diagram of the operation of a stirrer according to the third embodiment of the present invention. Figure 9 is an explanatory diagram of a stirrer according to the third embodiment of the present invention. In the following explanation, explanations of configurations similar to those of the first and second embodiments will be omitted, and only configurations that differ will be explained.

[0074] In the second embodiment, as shown in the operation diagram of FIG. 8, one third magnet, for example, a N pole very The magnetic field of the third magnet 222 (FIG. 6) having the property of being a south pole is very The magnetic field of third magnet 222 extends in the direction of third magnet 224, which has magnetic properties. However, if the magnetic field strengths of third magnet (north pole) 222 and third magnet (south pole) 224 are equivalent, the magnetic field of third magnet (north pole) 222 will only extend to a part of the area between third magnet (north pole) 222 and the mating third magnet (south pole) 224. In this way, the second embodiment smooths out the strength of the magnetic coupling and allows stirring bar 210 to move in a manner similar to a swinging motion, which is suitable for stirring; however, if the revolution speed is increased, there is a risk of the stirring bar leaving orbit 275.

[0075] The third embodiment is a modification of the stirring bar 210 of the second embodiment described with reference to FIGS. very The arrangement and orientation of the third magnets 222 and 224, which have different properties, are changed.

[0076] Referring to FIG. 9, a stirrer 510 of a stirrer 500 according to the third embodiment has adjacent third-A magnets (south poles) 522 spaced apart by an S-pole magnetic field region 527 and adjacent third-B magnets (north poles) 524 spaced apart by an N-pole magnetic field region 526, and the magnets are arranged so that they face each other. very It is structured so that the genders are the same.

[0077] 9, eight arm-shaped magnets extend radially at equal intervals from the rotation axis 230, and on each arm, a third-A magnet 522 and a third-B magnet 524 are arranged adjacent to each other in the circumferential direction. By arranging them in this way, the third-A magnet 522 and the third-B magnet 524 that are adjacent to each other with a gap between them can face each other. very The gender may be the same.

[0078] The third A magnet 522 and the third B magnet 524 are adjacent to each other with a gap between them. very By making the properties the same, the area of ​​the gap is wider and stronger than that of the second embodiment, which uses one magnet. very It is possible to form a north pole magnetic field region 526 and a south pole magnetic field region 527, which are polarized magnetic fields.

[0079] 10, the mechanism of rotation and revolution is the same as in the second embodiment. That is, as the stirring bar 510 rotates, the magnetic field formed by this magnetic coupling with the fourth magnet 264 and the fifth magnet 266 repeatedly attracts and repels the magnets, increasing the rotation speed of the stirring bar's rotation RS.

[0080] However, compared to the magnetic field of the single third magnets 222, 224 in the second embodiment, the magnetic field is wide and strong, with an N-pole magnetic field region 526 and an S-pole magnetic field region 527. Therefore, stable magnetic coupling can be maintained despite transient state changes such as attraction and repulsion due to magnetic coupling, and the positional relationship between the stirrer and the drive magnet unit. This configuration prevents the stirrer from departing from the revolution orbit 275, increases the rotational speed of the rotation and revolution RB, and improves stirring capacity.

[0081] In FIG. 9, the third-A magnet 522 and the third-B magnet 524 are arranged as a set in the form of eight radial arms, but this is just one example, and the number of arms and the spacing between them can be set appropriately to achieve magnetic coupling according to the state in the stirring layer, the type of liquid 6 in the tank, the required rotational speeds of the rotation and revolution RS and RB, etc.

[0082] Here, the difference in operation between the second embodiment and the third embodiment will be described in detail. The magnet arrangement in the second embodiment is one very Therefore, the force that binds the stirrer decreases rapidly as it moves away from the magnet. On the other hand, in the third embodiment, the magnetic flux density between magnets of the same polarity is high, and the reduction in the force restraining the stirrer is smaller than in the second embodiment. If there is little restraint as in the second embodiment, the stirrer will move inward and outward relative to the orbit.

[0083] In this way, rather than relying on external features (cylinder, cross, etc.), the arrangement of magnets ( very The second and third embodiments each have their own unique features, depending on the design (taking into consideration the efficiency of the rotor). With regard to "mixing efficiency," (1) the second embodiment: A larger area is mixed by blades or the like due to the swinging motion. In other words, a wider area is directly mixed with slow rotation. (2) the third embodiment: Mixing can be performed by increasing the rotation speed of the rotor. In other words, when mixing by rotation is required, the respective effects are achieved, in that the control range of the rotation speed is wide.

[0084] In stirring, the shear force appropriate to the material being stirred is an important factor. For example, fine chemical systems require a suitable rotation of the stirrer, while biochemical systems require reduced shear force to avoid damaging cells, etc. In the case of the second embodiment, it is difficult to increase the rotation speed, but by having the stirrer rotate and revolve over a wider range, stirring can be performed without generating large shear forces. On the other hand, in the case of the third embodiment, the rotation and revolution can be increased by setting the magnetic field region as needed, thereby increasing the shear force. In this way, it is appropriate to use the second and third embodiments appropriately depending on the material being stirred.

[0085] (Description of the Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is an explanatory diagram of a stirring bar according to the fourth embodiment of the present invention. In the following explanation, explanations of configurations similar to those of the first, second, and third embodiments will be omitted, and only configurations that differ will be described.

[0086] The stirring device 300 according to this embodiment is a modified example of the stirring bar 310. That is, the float 140 constituting the stirring devices 100 and 200 according to the first and second embodiments is replaced with a movable float 340 that can move up and down along the rotation axis.

[0087] According to this configuration, the movable float 340 can change its float position as shown in Figure 11(A) or (B) according to, for example, the liquid depth HB in Figure 1. The mechanism for changing the float position is not particularly limited, and may be mechanical or may be one in which the movable float 340 is attached to the rotation shaft 130 later.

[0088] With this configuration, even if the liquid level of the material to be stirred filled in the stirring tank changes, the position of the stirrer can be adjusted by adjusting the float position so that it does not come into contact with the bottom surface of the stirring tank.

[0089] (Description of an Example According to the Second Embodiment) Next, an example of the second embodiment of the present invention will be described with reference to Figures 12 and 13. Figure 12 is an explanatory diagram of a stirring bar according to an example of the present invention. Figure 13 is an image captured from a video of the operation of an example of the present invention.

[0090] 12, a stirrer 410 of a stirring device 400 according to one embodiment comprises a rotation shaft 430, an inverted truncated cone-shaped float 140 disposed above the rotation shaft 430, blades 445 extending radially from the rotation shaft 430, and a driven magnet section 420 disposed below the rotation shaft 430. Note that the basic configuration of the drive section and the like is omitted because it is the same as that of the second embodiment.

[0091] The specifications, configuration, dimensions, and test contents of this embodiment are listed below. The stirrer has four blades that protrude radially from the rotation axis. Four rectangular driven magnets are installed at the same positions as the four blades, extending radially from the rotation axis. The bottom surface of the driven magnet is configured to be parallel to the bottom surface of the water tank. A bipolar magnet is placed near the tip of the protrusion on the underside of each driven magnet section (the tip is approximately 40 mm from the rotation axis), and the diameter of the concentric circle for rotation is approximately 70 mm. The diameter of the concentric circles for revolution shall be approximately 130 mm. First, fill a square acrylic tank (300mm high x 300mm wide x 300mm deep) with approximately 16-17L (liters) of water. - Set the distance between the drive magnet and the bottom of the tank (outside the tank) to approximately 20 mm. Adjust the float so that the distance between the driven magnet and the bottom of the tank (inside the tank) is approximately 10 mm. · Check that the drive magnet section and the driven magnet section are magnetically coupled. Rotate the drive magnet (150 rpm).

[0092] The experimental results of this example are shown in Figures 13(A) and (B) as captured images from a video. As shown in Figure 13, this example confirmed that the stirring bar 410 can achieve revolution and rotation (planetary motion) without contact with the inside of the stirring tank (container 5). In other words, it was confirmed that the stirring device 400 with this configuration can mix the material to be stirred and achieve uniform stirring by the centrifugal force generated by the revolution and the shear stress caused by the rotation. In the experiment, the revolution rotation speed was 12 rpm, and the rotation rotation speed was 66 rpm.

[0093] As described above, the present invention can provide a magnetic coupling that transmits rotational force without contact, without relying on magnetic couplings that require the magnetic force of a superconducting bulk body or a complex magnet unit, and a stirring device that applies this to rotate a stirrer in an oscillatory manner.

[0094] Currently, there is a growing demand for agitation devices for uniformly mixing materials such as cell culture. For cell culture, it is desirable to slowly agitate the entire material without applying shear stress to the cells. Furthermore, to prevent the incorporation of foreign matter, there is a need for devices that are free from friction and wear and are completely sealed from the outside. The agitation device of the present invention can provide a stirring action that meets these requirements. [Explanation of symbols]

[0095] 5...container 6...Liquid 7 Bottom 10. Stirrer 100, 200, 300, 400, 500... Mixing device 110, 210, 310, 410, 510... Stirring bar 120, 220, 520... Driven magnet section 122 First magnet 125, 225... Concentric circles for rotation 130, 230, 430... Rotation axis 140···Float 145, 445... feathers 150, 250... Drive unit 160, 260... Drive magnet section 162 Second magnet 165, 272... Concentric circles for revolution 170, 270... revolution axis 175, 275... orbit 180···Motor 224...Third magnet 264···5th magnet 266···Fourth magnet 340···Moving float 522...3rd A magnet 524...3rd B magnet 526···N pole magnetic field region 527...S pole magnetic field region

Claims

1. A stirring device comprising: a stirring bar having a flat bottom surface and disposed in a container filled with a liquid; and a drive unit outside the container for rotating the stirring bar, The stirring bar is a rotation axis extending perpendicular to the bottom surface; a driven magnet section at one end of the bottom surface side of the rotation shaft, the driven magnet section extending radially from the rotation shaft with the circumference of a concentric circle for rotation centered on the rotation shaft as an outer edge so as to be parallel to the bottom surface, and in which a plurality of first magnets are arranged at intervals in the circumferential direction of the concentric circle for rotation; a float provided on the other end side of the rotation shaft to float the stirring bar to the liquid surface; The drive unit is a drive magnet unit formed in a disk shape, having an orbital axis at the center of the disk that serves as the rotation axis and the rotation axis for revolution of the stirrer, which rotates around the orbital axis so as to face the bottom surface, and which extends radially from the orbital axis with the circumference of a concentric circle for revolution centered on the orbital axis as its outer edge, and in which a plurality of second magnets that are opposite poles to the first magnets are arranged at intervals in the circumferential direction of the concentric circle for revolution; a rotation drive device that rotates the drive magnet portion, a diameter of the concentric circles for rotation is different from a diameter of the concentric circles for revolution, 10. A stirring device according to claim 9, wherein the buoyancy of the float is adjusted so that the driven magnet portion does not come into contact with the bottom surface of the container.

2. A stirring device comprising: a stirring bar having a flat bottom surface and disposed in a container filled with a liquid; and a drive unit outside the container for rotating the stirring bar, The stirring bar is a rotation axis extending perpendicular to the bottom surface; a driven magnet section in which a plurality of third magnets are arranged at one end of the bottom surface side of the rotation shaft, the third magnets being multi-polar magnets having two polarities spaced apart in the circumferential direction of the rotation concentric circle, the third magnets extending radially from the rotation shaft with the circumference of the rotation concentric circle centered on the rotation shaft as an outer edge, so as to be parallel to the bottom surface; a float provided on the other end side of the rotation shaft to float the stirring bar to the liquid surface; The drive unit is a drive magnet unit formed in a disk shape, having an orbital axis at the center of the disk that serves as the rotation axis and the rotation axis for revolution of the stirrer, which rotates around the orbital axis so as to face the bottom surface, and which extends radially from the orbital axis with the circumference of a concentric circle for revolution centered on the orbital axis as its outer edge, and in which a plurality of fourth magnets and a plurality of fifth magnets having polarities different from those of the fourth magnets are alternately arranged at intervals in the circumferential direction of the concentric circle for revolution; a rotation drive device that rotates the drive magnet portion, a diameter of the concentric circles for rotation is different from a diameter of the concentric circles for revolution, 10. A stirring device according to claim 9, wherein the buoyancy of the float is adjusted so that the driven magnet portion does not come into contact with the bottom surface of the container.

3. 3. The stirring device according to claim 2, wherein the polarities of the sides of the third magnets adjacent to each other with a gap therebetween are the same.

4. 4. The stirring device according to claim 1, wherein the diameter of the concentric circles for rotation is smaller than the diameter of the concentric circles for revolution.

5. 4. The stirring device according to claim 1, wherein one or more blades for stirring a liquid are attached to the rotation shaft and extend in a radial direction of the rotation of the rotation shaft.

6. 4. The stirring device according to claim 1, wherein the float is movable up and down along the rotation axis.

7. 4. The stirring device according to claim 1, wherein the float is filled with a liquid or a gas corresponding to the liquid.

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