JP7773620B2 - Plasma irradiation device and method for producing plasma-treated liquid - Google Patents

Description

This disclosure relates to technology for irradiating a workpiece with plasma.

Patent Document 1 describes a plasma irradiation device that includes a plasma generator that ejects plasma toward the inside of a cover housing, a gas supply device that supplies gas to the inside of the cover housing, a stage that is disposed inside the cover housing and on which an object to be treated is placed, and a movement device that moves the stage and arbitrarily changes the distance between the stage and the plasma ejection port of the plasma generator that ejects plasma into the inside of the cover housing.

In this plasma irradiation device, the distance between the stage and the plasma nozzle is adjusted by visually checking the scale on a graduated measuring rod installed next to the stage.

Patent No. 6697470

However, in the plasma irradiation device described in Patent Document 1, the distance between the stage and the plasma nozzle is adjusted by visually checking the scale on the measuring rod. Therefore, if a part is attached or detached, for example, for maintenance, the distance between the stage and the plasma nozzle changes before and after the part is attached or detached, which can result in a decrease in the quality of the plasma-irradiated treated liquid. The main cause of this is the inevitable occurrence of errors due to misalignment when adjusting the distance and parallax when reading the scale. Therefore, in the plasma irradiation device described in Patent Document 1, it is extremely difficult to return the distance to the properly adjusted distance after attaching or detaching a part.

The purpose of this disclosure is to provide technology that makes it possible to properly adjust the distance between the liquid to be treated and the plasma generator, and then return it to that proper distance.

In order to achieve the above object, the plasma irradiation device of the present disclosure includes a storage container for storing a liquid to be treated, a plasma generation device for generating plasma to be irradiated onto the liquid to be treated stored in the storage container, a movement mechanism capable of moving the storage container in either a direction toward or away from the plasma generation device in order to adjust the distance between the liquid to be treated stored in the storage container and the plasma generation device, an encoder that outputs position information indicating the amount of movement of the storage container moved by the movement mechanism, a stage for placing the storage container, and a shaft connected to the back surface of the stage , wherein the movement mechanism adjusts the distance between the liquid to be treated stored in the storage container and the plasma generation device by moving the shaft in the vertical direction, and the encoder is connected to the shaft and outputs position information indicating the amount of movement of the shaft moved by the moving mechanism, and the storage container has a storage section for storing the liquid to be treated, a liquid delivery pipe attachment section for attaching a liquid delivery pipe for delivering the liquid to be treated from outside the plasma irradiation device to the storage section, a drain hole provided on the bottom surface of the storage section for draining the liquid to be treated stored in the storage section, and a discharge section formed protruding downward from the storage container from a position including the drain hole, and the discharge section has a through hole communicating with the drain hole and a drain pipe attachment section for attaching a drain pipe for discharging the waste liquid passing through the through hole to the outside of the plasma irradiation device, and the stage has a notch for fitting the discharge section, and when the storage container is placed on the stage, it is placed by fitting the discharge section of the storage container into the notch of the stage .

This disclosure makes it possible to appropriately adjust the distance between the liquid to be treated and the plasma generator.

1 is a perspective view of an atmospheric pressure plasma irradiation device according to a first embodiment of the present disclosure. FIG. FIG. 2 is an exploded view of the plasma generating device in FIG. 1. FIG. 2 is an exploded view of the plasma generating device in FIG. 1. FIG. 2 is a cross-sectional view of the plasma generating device in FIG. 1. 1A is a perspective view of an irradiation block, and FIG. 1B is a cross-sectional perspective view taken along line BB of the irradiation block. FIG. 2 is a block diagram of a control device in FIG. 1 . FIG. 10 is a perspective view of an atmospheric plasma irradiation device according to a second embodiment of the present disclosure. FIG. 8 is a block diagram of the control device in FIG. 7 . 10 is a flowchart showing the procedure of a process for resetting an appropriate distance executed by a controller included in the control device of FIG. 8 .

Embodiments of the present disclosure are described in detail below with reference to the drawings.

(First embodiment)
1 shows an atmospheric plasma irradiation device 10 according to a first embodiment of the present disclosure. The atmospheric plasma irradiation device 10 is an apparatus for irradiating a culture solution (an example of a "liquid to be treated") with plasma under atmospheric pressure, and includes a plasma generator 20, a cover housing 22, an opening/closing mechanism 24, a stage 26, an elevating device 100, a purge gas supply mechanism 32 (see FIG. 6), a concentration detection mechanism 34 (see FIG. 6), and a control device 38. The width direction of the atmospheric plasma irradiation device 10 is referred to as the X direction, the depth direction of the atmospheric plasma irradiation device 10 as the Y direction, and the direction perpendicular to the X direction and the Y direction, i.e., the up-down direction, as the Z direction.

As shown in Figures 2 to 4, the plasma generator 20 includes a cover 50, an upper block 52, a lower block 54, a pair of electrodes 56, and a nozzle block 58. The cover 50 is generally shaped like a covered rectangular cylinder, with the upper block 52 disposed inside the cover 50. The upper block 52 is generally shaped like a rectangular parallelepiped and is made of ceramic. A pair of cylindrical recesses 60 are formed on the underside of the upper block 52.

The lower block 54 also has a generally rectangular parallelepiped shape and is molded from ceramic. A recess 62 is formed in the upper surface of the lower block 54, and the recess 62 is composed of a pair of cylindrical recesses 66 and a connecting recess 68 that connects the pair of cylindrical recesses 66. The lower block 54 is fixed to the underside of the upper block 52 while protruding from the lower end of the cover 50, and the cylindrical recess 60 of the upper block 52 and the cylindrical recess 66 of the lower block 54 are connected. The cylindrical recesses 60 and 66 have approximately the same diameter. A slit 70 is formed in the bottom surface of the recess 62, penetrating through to the underside of the lower block 54.

Each of the pair of electrodes 56 is disposed in a cylindrical space defined by a cylindrical recess 60 in the upper block 52 and a cylindrical recess 66 in the lower block 54. The outer diameter of the electrode 56 is smaller than the inner diameter of the cylindrical recesses 60, 66. The nozzle block 58 is generally flat and is fixed to the underside of the lower block 54. The nozzle block 58 has an ejection port 72 formed therein that communicates with the slit 70 in the lower block 54, and the ejection port 72 passes through the nozzle block 58 in the vertical direction.

The plasma generator 20 further includes a process gas supply device 74 (see Figure 6). The process gas supply device 74 supplies a process gas that is a mixture of an active gas such as oxygen and an inert gas such as nitrogen in any ratio, and is connected via piping (not shown) to the cylindrical space defined by the cylindrical recesses 60, 66 and to the top of the connecting recess 68. This allows the process gas to be supplied into the recess 62 from the gap between the electrode 56 and the cylindrical recess 66 and the top of the connecting recess 68.

With this structure, the plasma generator 20 ejects plasma from the nozzle 72 of the nozzle block 58. More specifically, a processing gas is supplied to the interior of the recess 62 by the processing gas supply device 74. At this time, a voltage is applied to the pair of electrodes 56 in the recess 62, and a current flows between the pair of electrodes 56. This causes a discharge between the pair of electrodes 56, which converts the processing gas into plasma. The plasma is then ejected from the nozzle 72 through the slit 70.

As shown in FIG. 1, the cover housing 22 also includes an upper cover 76 and a lower cover 78. The upper cover 76 is generally cylindrical with a lid, and a through-hole (not shown) shaped to fit the lower block 54 of the plasma generator 20 is formed in the lid of the upper cover 76. The cover 50 of the plasma generator 20 is fixed in an upright position to the lid of the upper cover 76 so as to cover the through-hole. As a result, the lower block 54 and nozzle block 58 of the plasma generator 20 protrude in the Z direction toward the interior of the upper cover 76. As a result, plasma generated by the plasma generator 20 is ejected in the Z direction from the ejection port 72 of the nozzle block 58 toward the interior of the upper cover 76.

In addition, three roughly rectangular through-holes (not shown) are formed at equally spaced positions on the side of the upper cover 76, and transparent glass plates 80 are arranged to cover the through-holes. This makes it possible to view the inside of the upper cover 76 through the glass plates 80.

The lower cover 78 of the cover housing 22 is generally disk-shaped and is fixed to the housing 79 of the mounting portion on which the atmospheric pressure plasma irradiation device 10 is placed. The outer diameter of the lower cover 78 is larger than the outer diameter of the upper cover 76, and a circular gasket (not shown) of the same diameter as the upper cover 76 is disposed on the upper surface of the lower cover 78. When the upper cover 76 is slid downward by the opening/closing mechanism 24, the upper cover 76 comes into close contact with the gasket, sealing the interior of the cover housing 22.

The opening/closing mechanism 24 includes a pair of slide mechanisms 86 and an air cylinder (not shown). Each slide mechanism 86 includes a support shaft 90 and a slider 92. The support shaft 90 is erected on the mounting unit housing 79 so as to extend in the Z direction. The slider 92 is generally cylindrical and is fitted onto the support shaft 90 so as to be slidable in the axial direction of the support shaft 90. The upper cover 76 is held to the slider 92 by an upper bracket 96 and a lower bracket 98. This allows the upper cover 76 to slide in the Z direction, i.e., up and down.

The stage 26 is generally disk-shaped, and the irradiation block 180 is placed on the upper surface of the stage 26. The outer diameter of the stage 26 is smaller than the outer diameter of the lower cover 78.

The irradiation block 180 stores the culture medium delivered via the delivery tube 122 and is used to generate a plasma-treated culture medium by irradiating the stored culture medium with plasma emitted from the plasma generator 20. The generated plasma-treated culture medium is discharged from the irradiation block 180 via the drainage tube 124.

The culture medium is supplied to the irradiation block 180 inside the cover housing 22 via a liquid supply tube 122 using a pump (not shown) from a culture medium supply unit (not shown) located outside the cover housing 22. The plasma-treated culture medium produced in the irradiation block 180 is drained from the irradiation block 180 via a drain tube 124 using a pump (not shown) and stored in a temporary storage bottle (not shown) located outside the cover housing 22. Therefore, through-holes 123 and 125 are formed in the side of the lower cover 78, through which the liquid supply tube 122 and the drain tube 124 pass, respectively.

Figure 5 shows the schematic configuration of the irradiation block 180. Figure 5(a) is a perspective view showing the overall appearance of the irradiation block 180, and Figure 5(b) is a cross-sectional perspective view taken along line BB in Figure 5(a). The direction from left to right is the direction in which the culture medium flows.

The irradiation block 180 is made of ceramic and consists of an irradiation block main body 181 that is generally rectangular. The long side of the irradiation block 180 is the X direction, and the short side is the Y direction. The irradiation block main body 181 is formed with a groove 183 and a reservoir 184, the surfaces of which are open on the side facing the plasma generator 20 when the irradiation block 180 is installed in the cover housing 22.

The groove 183 has a U-shape in the YZ cross section that opens upward. The bottom surface 183a that forms the groove 183 is curved. The YZ cross section of this groove 183 is slightly narrower than the cross-sectional shape of the liquid supply tube 122 (see Figure 1), and the flexible liquid supply tube 122 is fixed in place by fitting it into the groove 183.

Reservoir 184 stores the culture solution for plasma irradiation. Reservoir 184 is configured as a cylindrical recess consisting of side surfaces 184a and a bottom surface 184b. Bottom surface 184b of reservoir 184 is positioned lower than bottom surface 183a of groove 183. Bottom surface 184b of reservoir 184 is also formed with drainage holes 184c for discharging the plasma-treated culture solution produced by plasma irradiation of the culture solution from reservoir 184. Bottom surface 184b is inclined downward from side surface 184a toward drainage hole 184c. This is intended to quickly discharge the plasma-treated culture solution from reservoir 184 and to prevent, as much as possible, a state in which part of the plasma-treated culture solution remains in reservoir 184 without being discharged.

In addition to the above configuration, the irradiation block main body 181 also has a discharge section 186. The discharge section 186 is formed on the underside 181a of the irradiation block main body 181, protruding downward from a position that includes the drainage hole 184c of the storage section 184. The discharge section 186 has a base 186a, a flange 186b, and a discharge locking section 186c, and each of the components 186a to 186c is integrally formed and connected downward. Furthermore, a through-hole 186d is formed in the center of the discharge section 186 in the Z direction, and communicates with the drainage hole 184c of the storage section 184.

The base 186a is the portion of the outer peripheral surface of the discharge section 186 that is continuous with the underside 181a of the irradiation block main body 181. The diameter of the outer periphery of the discharge locking section 186c, which is formed below the base 186a and sandwiches the flange section 186b, is larger than the diameter of the drainage tube 124 (see FIG. 1). The outer diameter of the upper section 186c1 of the discharge locking section 186c is smaller than the outer diameter of the discharge locking section 186c. As a result, when the flexible drainage tube 124 is inserted up to the upper section 186c1, the drainage tube 124 deforms along the outer periphery of the discharge locking section 186c, thereby securing the drainage tube 124. The base 186a is fitted into the notch 26a of the stage 26 (see FIG. 1), securing the irradiation block 180 to the stage 26. In this way, since the irradiation block 180 is not fixed using a fixture, it can be easily attached and detached from the stage 26.

As shown in FIG. 1, the lifting device 100 includes a rotary operator 101, gear 102, rotation shaft 103, pinion holder 105, support rod 106, rack 107, and pinion (not shown). The rotary operator 101 is an operator that can rotate both clockwise and counterclockwise around the Y direction as its rotation axis. A bevel gear (not shown) is provided on the end of the rotation shaft of the rotary operator 101 that faces the gear 102. Gear 102 is also configured as a bevel gear, and the two gears are meshed. As a result, rotation of the rotary operator 101 around its rotation axis in the Y direction is converted, via gear 102, into rotation around its rotation axis in the X direction.

The gear 102 is provided with a rotation axis 103 in the X direction, and the rotation of the gear 102 directly results in the rotation of the rotation axis 103. The end of the rotation axis 103 opposite the gear 102 is connected to the rotation axis of the pinion.

A through-hole (not shown) that penetrates the lower cover 78 in the vertical direction is formed, and a support rod 106 is inserted into this through-hole. The outer diameter of the support rod 106 is smaller than the inner diameter of the through-hole, and the support rod 106 is movable in the vertical direction, i.e., the Z direction. The lower surface of the stage 26 is fixed to the upper end of the support rod 106.

The rack 107 is fixed to the outer peripheral surface of the portion of the support rod 106 that extends downward from the lower cover 78, so as to extend in the axial direction of the support rod 106. The pinion is meshed with the rack 107 and rotates with the rotation of the rotary shaft 103. The pinion holder 105 rotatably holds the pinion in the housing 79 of the mounting unit.

With this structure, when the operator rotates the rotary controller 101, the rotation of the rotary controller 101 around its axis of rotation in the Y direction is converted via the gear 102 into rotation around its axis of rotation in the X direction. The rotation of the gear 102 then rotates the rotation axis 103, which in turn rotates the pinion, causing the support rod 106 to move in the Z direction and the stage 26 to rise and fall. In this embodiment, when the rotary controller 101 is rotated clockwise, the support rod 106 moves upward, bringing the top surface of the stage 26 closer to the nozzle 72, and when the rotary controller 101 is rotated counterclockwise, the support rod 106 moves downward, bringing the top surface of the stage 26 away from the nozzle 72. However, the relationship between the rotation direction of the rotary controller 101 and the direction in which the stage 26 and the nozzle 72 approach and move away from each other may be reversed.

The lower end of the support rod 106 is connected to the encoder section 112 of the scale unit 110 via a connecting member 108. In this embodiment, the scale unit 110 is configured as a so-called linear encoder, and is primarily composed of the encoder section 112 and the scale section 114. The encoder section 112 moves in the Z direction on the scale section 114, and outputs a pulse signal corresponding to the amount of movement during this movement. In this embodiment, the scale unit 110 uses an encoder section 112 that outputs one pulse for every 1/100 mm of movement, for example, but the detection accuracy is not limited to this and may be slightly less accurate or more accurate.

As described above, the encoder unit 112 is connected to the support rod 106, so when the support rod 106 moves in the Z direction, the encoder unit 112 also moves in the Z direction by the same amount. Therefore, the encoder unit 112 detects and outputs the amount of movement of the support rod 106, i.e., the amount of elevation of the stage 26.

There are two types of linear encoders (as well as rotary encoders): incremental and absolute. Incremental types output a number of pulse signals corresponding to the amount of movement of the scale section 114 by the encoder section 112, while absolute types output the absolute position of the detection point. In this embodiment, an incremental type is used as the scale unit 110.

As shown in FIG. 1, the purge gas supply mechanism 32 includes an air joint 130 and a purge gas supply device 132 (see FIG. 6). The air joint 130 is provided on the lid portion of the upper cover 76. The purge gas supply device 132 is a device that supplies an inert gas such as nitrogen, and is connected to the air joint 130 via piping (not shown). With this structure, the purge gas supply mechanism 32 supplies an inert gas to the interior of the upper cover 76.

As shown in FIG. 6, the control device 38 includes a controller 170 and multiple drive circuits 172. The multiple drive circuits 172 are connected to the electrode 56, process gas supply device 74, purge gas supply device 132, and display 120. The controller 170 is primarily a computer, including a CPU, ROM, RAM, etc., and is connected to the multiple drive circuits 172. This allows the controller 170 to control the operation of the plasma generator 20 and purge gas supply mechanism 32. The controller 170 is also connected to the detection sensor 144 and the encoder unit 112. This allows the controller 170 to obtain the detection result of the detection sensor 144, i.e., the oxygen concentration inside the cover housing 22, and to obtain the pulse signal output by the encoder unit 112.

When the controller 170 receives a pulse signal from the encoder unit 112, it counts up or down by one the count value stored in a count area (not shown) secured in the RAM. That is, the controller 170 counts up when the encoder unit 112 is moving upward, and counts down when the encoder unit 112 is moving downward. Then, upon counting up/down, the controller 170 calculates the amount of movement of the encoder unit 112 corresponding to the new count value, and rewrites the display area (not shown) that the display 120 refers to when displaying with that amount of movement. As a result, the updated amount of movement is displayed on the display 120.

Irradiating a culture medium with plasma activates the culture medium, and plasma is expected to be utilized in the medical field, such as in cancer treatment using plasma-irradiated culture medium. For this reason, plasma-irradiated culture medium is produced, and it is preferable that the culture medium be irradiated with plasma under controlled conditions. With the above-described configuration, the atmospheric pressure plasma irradiation device 10 places the irradiation block 180 on the stage 26 and seals the cover housing 22, making it possible to irradiate the culture medium with plasma under specified conditions. Below, a detailed description is given of the method for irradiating the culture medium with plasma under specified conditions.

Specifically, first, the irradiation block 180 is placed on the stage 26. Next, the lifting device 100 raises and lowers the stage 26 to the desired height. This makes it possible to arbitrarily set the distance between the plasma nozzle 72 and the culture solution, which serves as the object to be irradiated by the plasma. As described above, the height at which the stage 26 is raised and lowered is displayed on the display 120 in 1/100 mm increments, eliminating the possibility of visual error, as occurs with the plasma irradiation device described in Patent Document 1 above.

Next, the upper cover 76 is lowered to seal the cover housing 22. The purge gas supply mechanism 32 then supplies inert gas into the cover housing 22. At this time, the concentration detection mechanism 34 detects the oxygen concentration inside the cover housing 22. After the detected oxygen concentration falls below a preset threshold, the plasma generator 20 sprays plasma into the cover housing 22. Note that the supply of inert gas into the cover housing 22 continues even while plasma is being emitted. Furthermore, culture fluid adjusted to a constant flow rate is flowed via the fluid delivery tube 122 into the reservoir 184 of the irradiation block 180. The culture fluid stored in the reservoir 184 is activated by irradiating it with plasma gas from the plasma generator 20. It has been shown that irradiating the culture fluid with plasma gas for a predetermined period of time can exert a therapeutic effect through the plasma-irradiated culture fluid. The culture fluid is stored in the reservoir 184, where it is irradiated with plasma gas for a predetermined period of time. Furthermore, when the culture medium is irradiated with plasma gas, natural convection occurs within the reservoir 184. This allows for the creation of a homogeneous, activated culture medium that exerts therapeutic effects.

In this way, by supplying inert gas to the interior of the cover housing 22, the air inside the cover housing 22 is exhausted to the outside of the cover housing 22. At this time, the oxygen concentration inside the cover housing 22 is adjusted to control the conditions that affect plasma irradiation. Specifically, because plasma contains active radicals, when it reacts with oxygen it becomes ozone, reducing the effectiveness of plasma irradiation. Therefore, by adjusting the oxygen concentration inside the cover housing 22, it is possible to examine the effect of oxygen concentration on the effectiveness of plasma-irradiated culture solution. It also becomes possible to irradiate plasma to culture solution under the same conditions. This makes it possible to efficiently produce plasma-treated culture solution.

Furthermore, as described above, the atmospheric pressure plasma irradiation device 10 allows the distance between the plasma nozzle 72 and the culture solution to be set arbitrarily. This makes it possible to investigate the influence of irradiation distance on the effects of plasma-irradiated culture solution, enabling efficient production of plasma-treated culture solution.

When a predetermined time has elapsed since plasma irradiation began, the plasma-treated culture solution stored in storage section 184 is discharged via drainage tube 124. When a predetermined time has elapsed since discharge of the plasma-treated culture solution from storage section 184 began, it is assumed that no plasma-treated culture solution remains in storage section 184, and discharge of the plasma-treated culture solution from storage section 184 is completed. The next culture solution to be plasma-treated is then flowed via drainage tube 122 into storage section 184 of irradiation block 180. This plasma treatment process, which involves irradiating the culture solution stored in storage section 184 with plasma for a predetermined time, draining the plasma-treated culture solution, supplying new culture solution to irradiation block 180, and irradiating the culture solution with plasma, is then repeated until a predetermined amount of plasma-treated culture solution is produced.

Now, suppose that the distance between the plasma nozzle 72 and the culture solution is set to the appropriate distance, and then, for maintenance, the supply tube 122 or the drainage tube 124, for example, needs to be replaced. This replacement operation will inevitably cause the distance between the plasma nozzle 72 and the culture solution to deviate from the appropriate distance. However, if the operator makes a note of the amount of movement displayed on the display 120 before the operation, after the operation, the operator can simply operate the rotary control 101 so that the amount of movement that matches that amount is displayed on the display 120, easily and quickly restoring the distance to the appropriate distance before the operation.

As described above, the atmospheric pressure plasma irradiation device 10 of this embodiment comprises an irradiation block 180 that stores culture solution, a plasma generator 20 that generates plasma to irradiate the culture solution stored in the irradiation block 180, an elevator device 100 that can move the irradiation block 180 in either a direction toward or away from the plasma generator 20 in order to adjust the distance between the culture solution stored in the irradiation block 180 and the plasma generator 20, and a scale unit 110 that outputs position information indicating the amount of movement of the irradiation block 180 moved by the elevator device 100.

In this way, the atmospheric pressure plasma irradiation device 10 of this embodiment can appropriately adjust the distance between the culture solution and the plasma generator 20 based on the position information output from the scale unit 110, and then return it to that appropriate distance.

Incidentally, in this embodiment, the atmospheric pressure plasma irradiation device 10 is an example of a "plasma irradiation device." The culture fluid is an example of a "liquid to be treated." The irradiation block 180 is an example of a "storage container." The lifting device 100 is an example of a "moving mechanism." The scale unit 110 is an example of an "encoder."

The atmospheric pressure plasma irradiation device 10 of this embodiment also includes a display 120 that displays the position information output by the scale unit 110. The display 120 is an example of an "indicator." This allows the operator to return the distance between the culture medium and the plasma generator 20 to the appropriate distance while looking at the position information displayed on the display 120, making it possible to perform this operation easily and quickly.

The lifting device 100 also has a rotary operator 101 that can rotate clockwise and counterclockwise, and a rack 107 and pinion that convert the amount of rotation by the rotary operator 101 into the amount of movement of the irradiation block 180. Incidentally, the rack 107 and pinion are an example of a "conversion mechanism."

The atmospheric plasma irradiation device 10 of this embodiment also includes a stage 26 for placing the irradiation block 180, and a support rod 106 connected to the back surface of the stage 26. The lifting device 100 adjusts the distance between the culture solution stored in the irradiation block 180 and the plasma generator 20 by moving the support rod 106 up and down, and the scale unit 110 is connected to the support rod 106 and outputs position information indicating the amount of movement of the support rod 106 moved by the lifting device 100. Incidentally, the support rod 106 is an example of a "shaft."

The irradiation block 180 also has a storage section 184 for storing the culture solution, a groove section 183 for attaching a liquid supply tube 122 for supplying the culture solution from the outside of the plasma irradiation device 10 to the storage section 184, a drainage hole 184c provided on the bottom surface 184b of the storage section 184 for draining the culture solution stored in the storage section 184, and a discharge section 186 formed by protruding downward from a position including the drainage hole 184c to the irradiation block 180. The discharge section 186 has a drainage hole 184c. 84c, and a discharge locking portion 186c for attaching a discharge tube 124 for discharging the discharged liquid passing through the through hole 186d to the outside of the plasma irradiation device 10. The stage 26 has a notch 26a for fitting the discharge portion 186. When placing the irradiation block 180 on the stage 26, the discharge portion 186 of the irradiation block 180 is fitted into the notch 26a of the stage 26. Incidentally, the liquid supply tube 122 is an example of a "liquid supply tube." The groove portion 183 is an example of a "liquid supply tube mounting portion." The drain tube 124 is an example of a "liquid drain tube." The discharge locking portion 186c is an example of a "liquid drain tube mounting portion."

Second Embodiment
7 shows an atmospheric plasma irradiation apparatus 10A according to a second embodiment of the present disclosure. The atmospheric plasma irradiation apparatus 10A differs from the atmospheric plasma irradiation apparatus 10 of the first embodiment only in a partial configuration of the lifting device 200 and a partial configuration of the control device 38. Therefore, in FIGS. 7 and 8, the same components as those in FIGS. 1 and 6 are denoted by the same reference numerals, and their description will be omitted as appropriate.

As shown in Figure 7, the lifting device 200 replaces the rotary operator 101 and gear 102 included in the lifting device 100 with an electromagnetic motor 210. For this reason, as shown in Figure 8, a drive circuit 172 for driving the electromagnetic motor 210 has been added to the control device 38A. An UP key 150 for moving the stage 26 upward by a predetermined distance and a DOWN key 152 for moving the stage 26 downward by a predetermined distance have also been added.

Figure 9 shows the steps in the process of resetting the appropriate distance executed by the controller 170. Hereafter, in the explanation of each process step, steps will be abbreviated as "S." This process of resetting the appropriate distance includes not only steps S24 to S36 that automatically reset the appropriate distance, but also steps S10 to S20 that set the appropriate distance before that. However, if the appropriate distance has been set in advance, steps S10 to S20 may be omitted.

In Figure 9, the controller 170 first determines whether an appropriate distance has been set (S10). The determination of whether the distance is appropriate is made, for example, by actually irradiating plasma onto the culture solution while changing the distance between the plasma nozzle 72 and the culture solution, checking the quality of the plasma-treated culture solution each time, and determining the distance at which the best quality is obtained as the optimal distance.

If the determination in S10 indicates that an appropriate distance has not been set (S10: NO), the controller 170 determines whether the UP key 150 has been pressed (S12). If the UP key 150 has been pressed (S12: YES), the controller 170 outputs a command to the drive circuit 172 to rotate the electromagnetic motor 210 forward a predetermined number of revolutions (S14). This causes the support rod 106 to move upward a predetermined distance, thereby reducing the distance between the plasma nozzle 72 and the culture solution by the predetermined distance. The controller 170 then reads the count value stored in the count area described above in the first embodiment, obtains the current distance based on the read count value (S20), and returns the process to S10.

On the other hand, if the UP key 150 has not been pressed in the determination at S12 (S12: NO), the controller 170 determines whether the DOWN key 152 has been pressed (S16). If the DOWN key 152 has been pressed (S16: YES), the controller 170 outputs a command to the drive circuit 172 to rotate the electromagnetic motor 210 in the reverse direction a predetermined number of revolutions (S18). This causes the support rod 106 to move downward a predetermined distance, thereby increasing the distance between the plasma nozzle 72 and the culture solution by the predetermined distance. The controller 170 then proceeds to S20, reads the count value stored in the count area, obtains the current distance based on the read count value, and returns to S10.

On the other hand, if the appropriate distance is set in the determination of S10 above (S10: YES), the controller 170 stores the current distance obtained in S20 above as the appropriate distance, for example, in an appropriate distance storage area (not shown) secured in RAM (S22).

The controller 170 then determines whether an instruction to automatically reset the appropriate distance has been issued (S24). An instruction to automatically reset the appropriate distance may be issued, for example, by an instruction button (not shown) provided and the operator pressing the instruction button. If the determination in S24 indicates that an instruction to automatically reset the appropriate distance has not been issued (S24: NO), the controller 170 waits until such an instruction is issued, and when such an instruction is issued (S24: YES), the controller 170 obtains the current distance in the same manner as in S20 above (S26).

The controller 170 then continues to monitor the current distance until it matches the appropriate distance stored in S22 (S36: YES). If the current distance is greater than the appropriate distance (S28: YES), the controller 170 outputs a command to the drive circuit 172 to rotate the electromagnetic motor 210 in the reverse direction by a predetermined number of rotations (S30), as in S18 above. If the current distance is less than the appropriate distance (S32: YES), the controller 170 outputs a command to the drive circuit 172 to rotate the electromagnetic motor 210 in the forward direction by a predetermined number of rotations (S34), as in S14 above. In this way, while there is a discrepancy between the current distance and the appropriate distance, the support rod 106 is moved in a direction that reduces the discrepancy. As a result, the distance between the plasma nozzle 72 and the culture solution converges to the appropriate distance. When the current distance matches the appropriate distance (S36: YES), the controller 170 terminates the automatic resetting of the appropriate distance.

Note that in the processes of S14, S18, S30, and S34, the electromagnetic motor 210 is instructed to rotate a predetermined number of revolutions, but the predetermined number of revolutions may be the same for each process, or may be different for each process. Alternatively, the number of revolutions may be the same for S14 and S18, and the same for S30 and S34, but different for S14 and S30.

As such, in the atmospheric pressure plasma irradiation device 10A of this embodiment, the lifting device 200 has an electromagnetic motor 210, and a rack 107 and pinion that convert the amount of rotation of the rotation shaft of the electromagnetic motor 210 into the amount of movement of the storage section 184. Incidentally, the electromagnetic motor 210 is an example of a "motor."

The atmospheric pressure plasma irradiation device 10A of this embodiment also includes a controller 170 that controls the electromagnetic motor 210 so that the distance between the culture solution stored in the irradiation block 180 and the plasma generator 20 is a specified distance. Incidentally, the controller 170 is an example of a "control unit." This allows the electromagnetic motor 210 to automatically return the distance between the culture solution and the plasma generator 20 to the appropriate distance.

The atmospheric pressure plasma irradiation device 10A of this embodiment also includes a stage 26 for placing the irradiation block 180, and a support rod 106 connected to the back surface of the stage 26. The lifting device 200 adjusts the distance between the culture solution stored in the irradiation block 180 and the plasma generator 20 by moving the support rod 106 up and down, and the scale unit 110 is connected to the support rod 106 and outputs position information indicating the amount of movement of the support rod 106 moved by the lifting device 200.

Note that this disclosure is not limited to the above embodiments, and various modifications are possible without departing from the spirit of the disclosure.

In each of the above embodiments, a culture medium is used as the object to be treated, but it is possible to use liquids other than a culture medium as the object to be treated. Furthermore, the present disclosure is not limited to the medical field, and can be applied to various fields, such as the industrial field.

10, 10A...atmospheric pressure plasma irradiation device, 20...plasma generator, 26...stage, 38, 38A...controller, 72...nozzle, 100, 200...elevating device, 101...rotary operator, 102...gear, 103...rotating shaft, 105...pinion holder, 106...support rod, 107...rack, 110...scale unit, 112...encoder, 114...scale, 120...display, 132...purge gas supply device, 150...UP key, 152...DOWN key, 170...controller, 180...irradiation block, 184...storage section, 210...electromagnetic motor.

Claims (6)

a storage container for storing the liquid to be treated;
a plasma generating device that generates plasma to be irradiated onto the liquid to be treated stored in the storage container;
a movement mechanism that can move the storage container in either a direction toward the plasma generator or a direction away from the plasma generator in order to adjust the distance between the liquid to be treated stored in the storage container and the plasma generator;
an encoder that outputs position information indicating the amount of movement of the storage container moved by the movement mechanism;
a stage for placing the storage container;
a shaft connected to the rear surface of the stage;
A plasma irradiation device comprising:
the moving mechanism adjusts the distance between the liquid to be treated stored in the storage container and the plasma generator by moving the shaft up and down;
the encoder is coupled to the shaft and outputs position information indicating a movement amount of the shaft moved by the movement mechanism;
The storage container has a storage section for storing the liquid to be treated, a liquid feed tube attachment section for attaching a liquid feed tube for feeding the liquid to be treated from the outside of the plasma irradiation device to the storage section, a drain hole provided in the bottom surface of the storage section for draining the liquid to be treated stored in the storage section, and a discharge section formed to protrude downward from a position including the drain hole of the storage container,
The discharge portion is formed with a through hole communicating with the drain hole, and a drain pipe attachment portion for attaching a drain pipe for discharging the drained liquid passing through the through hole to the outside of the plasma irradiation device,
The stage is formed with a notch into which the discharge portion is fitted,
When the storage container is placed on the stage, the storage container is placed by fitting the discharge portion of the storage container into the notch of the stage.
Plasma irradiation device. The plasma irradiation device according to claim 1 , further comprising a display that displays the position information output by the encoder. The moving mechanism includes:
A rotary operator that can rotate clockwise and counterclockwise;
a conversion mechanism that converts a rotation amount rotated by the rotary operator into a movement amount of the storage container;
The plasma irradiation device according to claim 1 or 2, comprising: The moving mechanism includes:
A motor;
a conversion mechanism that converts the rotation amount of the rotation shaft of the motor into the movement amount of the storage container;
The plasma irradiation device according to claim 1 or 2, comprising: 5. The plasma irradiation device according to claim 4, further comprising a control unit that controls the motor so that the distance between the liquid to be treated stored in the storage container and the plasma generator is a designated distance. a moving mechanism that can move the storage container in either a direction toward or away from the plasma generator in order to adjust the distance between the liquid to be processed stored in the storage container and the plasma generator; an encoder that outputs position information that indicates the amount of movement of the storage container moved by the movement mechanism; a stage for placing the storage container; and a shaft connected to the back surface of the stage, wherein the movement mechanism moves the shaft in a vertical direction to adjust the distance between the liquid to be processed stored in the storage container and the plasma generator; the encoder that is connected to the shaft and outputs position information that indicates the amount of movement of the shaft moved by the movement mechanism; a storage container having a storage section for storing the liquid to be treated, a liquid delivery pipe attachment section for attaching a liquid delivery pipe for delivering the liquid to be treated from outside the plasma irradiation device to the storage section, a drain hole provided on the bottom surface of the storage section for draining the liquid to be treated stored in the storage section, and a discharge section formed protruding downward from a position including the drain hole, the discharge section having a through hole communicating with the drain hole and a drain pipe attachment section for attaching a drain pipe for discharging the drained liquid passing through the through hole to the outside of the plasma irradiation device, the stage having a notch for fitting into the discharge section, and when the storage container is placed on the stage, the discharge section of the storage container is placed by fitting the discharge section of the storage container into the notch of the stage, a plasma treatment liquid production method for producing a plasma treatment liquid by irradiating plasma to the liquid to be treated stored in the storage container using a plasma irradiation device .