Patent Publication Number: US-2020292508-A1

Title: Column oven and chromatography

Description:
BACKGROUND OF THE INVENTION 
     1. Technical Field 
     The present invention relates to a column oven and a chromatography. 
     2. Background Art 
     A chromatography device configured to separate a mobile phase targeted for analysis into multiple components, i.e., analytes, by a separation column has been known (e.g., see Patent Literature 1 (JP-T-2003-531389)). The chromatography device described in Patent Literature 1 includes a processing zone configured to house the separation column and a heating portion configured to cause air to circulate while heating the air to heat the separation column in the processing zone. The heating portion has a coil (a heater) configured to generate heat by power distribution and an air blower fan. 
     However, in the chromatography described in Patent Literature 1, there is a problem that depending on the flow rate (the wind volume) of the circulating air, uneven heating such as excessive heating of the separation column or insufficient heating of the separation column is caused. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide a column oven and a chromatography configured so that an analysis column can be uniformly heated. 
     A column oven comprises: a hollow housing; an analysis column arranged in the housing and allowing circulation of a mobile phase in the analysis column; a heating portion configured to heat air; a swirl flow generation portion configured to discharge, as a swirl flow, the air heated by the heating portion into the housing; and a throttle portion configured to throttle the swirl flow when the swirl flow is discharged into the housing. The throttle portion has multiple through-holes formed to penetrate the throttle portion along a direction of discharging the swirl flow and arranged in a honeycomb shape as viewed from a swirl flow discharge side. 
     According to the present invention, air can contact the analysis column when passing through a housing, and can heat the analysis column. At this point, the temperature of the air decreases as the air passes through the housing (as the air flows apart from a heating portion). However, a flow rate is increased by a throttle portion, and therefore, a temperature decrease in the housing can be suppressed as much as possible. With this configuration, the entirety of the analysis column can be uniformly heated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram (a block diagram) of an embodiment of a chromatography system of the present invention; 
         FIG. 2  is a partial vertical sectional view of an internal structure of a column oven provided at the chromatography system illustrated in  FIG. 1 ; and 
         FIG. 3  is a view from a direction indicated by an arrow A of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
     Hereinafter, a column oven and a chromatography of the present invention will be described in detail based on a preferred embodiment illustrated in the attached drawings. 
       FIG. 1  is a schematic diagram (a block diagram) of an embodiment of a chromatography system of the present invention.  FIG. 2  is a partial vertical sectional view of an internal structure of a column oven provided at the chromatography system illustrated in  FIG. 1 .  FIG. 3  is a view from a direction indicated by an arrow A of  FIG. 2 . 
     Note that for the sake of convenience in description, one direction of the horizontal direction will be hereinafter referred to as an “X-axis direction,” a direction perpendicular to the X-axis direction of the horizontal direction will be hereinafter referred to as a “Y-axis direction,” and the vertical direction, i.e., a direction perpendicular to the X-axis direction and the Y-axis direction, will be hereinafter referred to as a “Z-axis direction.” Moreover, aside indicated by an arrow in each axial direction will be referred to as a “positive side,” and a side opposite to the arrow will be referred to as a “negative side.” Further, an upper side in  FIGS. 2 and 3  will be referred to as “upper (or above),” and a lower side will be referred to as “lower (or below).” 
     Hereinafter, a case where a chromatography system  1  is applied to a liquid chromatography system configured to perform analysis for a liquid sample as one type of mobile phase Q under multiple analysis conditions will be described as one example, but the chromatography system  1  is also similarly applicable to a supercritical fluid chromatography system and a gas chromatography system. 
     As illustrated in  FIG. 1 , the chromatography system  1  includes a solution sending device  20 , an auto-sampler  40 , a column oven  6 , a detector  80 , and a system management device  10  forming a device main body  11  in the chromatography system  1 ; and a replaceable analysis column  121  detachable from the device main body  11 . 
     The solution sending device  20 , the auto-sampler  40 , the column oven  6 , and the detector  80  are arranged in this order along a flow direction of the mobile phase Q, i.e., from an upstream side to a downstream side. Moreover, the solution sending device  20 , the auto-sampler  40 , the column oven  6 , and the detector  80  are connected to each other through a pipe forming a flow path  13 . The mobile phase Q can circulate in the flow path  13 . 
     Note that in addition to the sample targeted for analysis, examples of the mobile phase Q include a buffer solution used upon analysis and a cleaning solution such as an organic solvent for cleaning a stationary phase. 
     Moreover, the system management device  10  is electrically connected to the solution sending device  20 , the auto-sampler  40 , the column oven  6 , and the detector  80 . The system management device  10  includes, for example, a CPU configured to execute logical operation, a ROM configured to store an operation program necessary for control of the solution sending device  20  and the like, and a RAM configured to temporarily store data and the like upon control. The system management device  10  can control the entirety of the chromatography system  1 . 
     The solution sending device  20  has, for example, a solution sending pump, and by such a solution sending pump, the mobile phase Q can be transferred to the downstream side in the flow path  13 . Moreover, the number of rotations of the solution sending pump is changed so that the transfer speed of the mobile phase Q can be adjusted. 
     The auto-sampler  40  is for injecting the mobile phase Q into the flow path  13 . 
     The column oven  6  can be filled with the analysis column  121 . Thus, the analysis column  121  is arranged in the middle of the flow path  13 , and the sample can be injected into the mobile phase Q from the auto-sampler  40  and can circulate (pass) in the analysis column  121 . At this point, such a sample can be separated into multiple components. 
     The column oven  6  can heat the analysis column  121  together with the sample. Thus, the temperature of the sample can be adjusted to a predetermined temperature. A configuration of the column oven  6  will be described later. 
     The detector  80  is for detecting the components separated in the analysis column  121 . 
     Moreover, as illustrated in  FIG. 1 , the chromatography system  1  includes the system management device  10 . The system management device  10  includes an analysis condition setting section  14 , a determination section  15 , an input section  17 , and a first storage section  16 . 
     Moreover, in the chromatography system  1 , the analysis column  121  and a second storage section  122  attached to the analysis column  121  together form a column unit  12 . Upon replacement of the analysis column  121 , the analysis column  121  and the second storage section  122  are together replaced. 
     The analysis condition setting section  14  can set the multiple analysis conditions. The analysis conditions include, for example, the type of sample and the type of stationary phase charged into the analysis column  121 . Thus, the chromatography system  1  can analyze the sample under the multiple analysis conditions. 
     For example, in a case where there are two types of samples targeted for analysis, the analysis condition setting section  14  sets a first analysis condition when analysis is performed for one of the samples, and sets a second analysis condition different from the first analysis condition when analysis is performed for the other sample. The analysis column  121  suitable for analysis for one of the samples is used under the first analysis condition, and the analysis column  121  suitable for analysis for the other sample is used under the second analysis condition. 
     The determination section  15  determines, for example, whether or not the analysis condition set by the analysis condition setting section  14  can be selected. 
     The first storage section  16  stores mobile phase information regarding the type of mobile phase Q in advance, for example. The first storage section  16  can store, for example, the mobile phase information with the name or number of the mobile phase Q. 
     The second storage section  122  stores second information as individual information on the analysis column  121 , for example. In the present embodiment, the analysis column  121  is specified by the type of stationary phase charged into the analysis column  121 . Moreover, the analysis column  121  itself can be specified by the second information. 
     Next, the configuration of the column oven  6  will be described. 
     As illustrated in  FIG. 2 , the column oven  6  includes a hollow housing  61 , a swirl flow generation portion  62  configured to generate a swirl flow in the housing  61 , a heating portion  63  configured to heat the analysis column  121  in the housing  61 , multiple holding portions  2  configured to hold the analysis column  121  in the housing  61 , a plate-shaped stationary plate  3  to which the holding portions  2  are detachably fixed in the housing  61 , and a throttle portion  9  as a discharge member configured to discharge the swirl flow. 
     The housing  61  includes a box body having an upper wall portion  611  arranged on the upper side, a lower wall portion  612  arranged on the lower side, and multiple side wall portions  613  arranged between the upper wall portion  611  and the lower wall portion  612 . Note that at least these wall portions of the housing  61  preferably have thermal insulating properties. 
     Moreover, the housing  61  has a partition wall portion  614  configured to divide the inside of the housing  61  into a first space  615  and a second space  616 . In the configuration illustrated in  FIG. 2 , the partition wall portion  614  divides the first space  615  to the positive side in the X-axis direction, and divides the second space  616  to the negative side in the X-axis direction. Moreover, the analysis column  121 , the holding portions  2 , and the stationary plate  3  are arranged in the first space  615 . On the other hand, the swirl flow generation portion  62  and the heating portion  63  are arranged in the second space  616 . Further, the throttle portion  9  is arranged between the first space  615  and the second space  616 , i.e., at the partition wall portion  614 . 
     The heating portion  63  has a heater  631  configured to generate heat by power distribution, and the heater  631  generates heat to heat air AR in the housing  61  (the second space  616 ). By such air AR, the analysis column  121  held by the holding portions  2  and the sample can be heated together. In this manner, the temperature of the sample can be adjusted to the predetermined temperature. 
     The swirl flow generation portion  62  is arranged on the upper side with respect to the heating portion  63 . The swirl flow generation portion  62  discharges, as the swirl flow, the air AR heated by the heating portion  63  into the first space  615 . Then, the air AR discharged into the first space  615  is provided for heating the analysis column  121 . 
     The swirl flow generation portion  62  has a rotatably-supported fan  621 , and such a fan rotates to generate the swirl flow. In this manner, the air AR heated by the heating portion  63  can be reliably discharged into the first space  615 . 
     Moreover, the partition wall portion  614  includes a fixing port  617  at which the throttle portion  9  configured to discharge the air AR into the first space  615  is arranged in a fixed manner, and a suction port  618  positioned below the fixing port  617  and configured to suck the air AR in the first space  615  into the second space  616 . Thus, the air AR can circulate between the first space  615  and the second space  616 . By such circulation, the air AR is heated by the heating portion  63  in the second space  616 , and thereafter, can heat the analysis column  121  in the first space  615 . Thus, the air AR provided for heating the analysis column  121  and having a decreased temperature can be heated again, and therefore, the temperature of the air AR can be promptly increased to a desired temperature. 
     Note that the analysis column  121  is heated by the circulating air AR in the column oven  6 , but the present invention is not limited to above. For example, it may be configured such that the analysis column  121  is heated by radiation heat (radiated heat) by a heating block. 
     The analysis column  121  is in an elongated shape, and is arranged along the vertical direction, i.e., the Z-axis direction, in the first space  615  of the housing  61 . Note that the analysis column  121  is arranged along the Z-axis direction in the present embodiment, but the present invention is not limited to above. For example, the analysis column  121  may be arranged along the X-axis direction or the Y-axis direction. 
     The analysis column  121  has a base end portion  123  positioned on the upstream side in the flow direction of the mobile phase Q, a tip end portion  124  positioned on the downstream side in the flow direction, and an intermediate portion  125  between the tip end portion  124  and the base end portion  123 . In the present embodiment, the analysis column  121  is used with the base end portion  123  being arranged on the upper side and the tip end portion  124  being arranged on the lower side. 
     Of the base end portion  123 , the tip end portion  124 , and the intermediate portion  125  of the analysis column  121 , the intermediate portion  125  is held by the holding portions  2 . In the present embodiment, the intermediate portion  125  has a circular cross-sectional shape, and the outer diameter thereof is constant along the Z-axis direction. 
     As illustrated in  FIG. 2 , the analysis column  121  is held by two holding portions  2  in the first space  615 . These two holding portions  2  are preferably separated from each other as much as possible in the Z-axis direction. With this configuration, the state of holding the analysis column  121  is stabilized. Note that the number of holding portions  2  used for holding the analysis column  121  is two in the present embodiment, but the present invention is not limited to above. For example, the number of holding portions  2  may be one or three or more. 
     Moreover, each holding portion  2  is fixed to the housing  61  through the stationary plate  3 . As illustrated in  FIG. 2 , the stationary plate  3  is in a plate shape, and as a whole, is arranged parallel with a Y-axis and a Z-axis, i.e., parallel with a YZ plane. 
     As described above, the throttle portion  9  is fixed to the fixing port  617  of the partition wall portion  614 . As illustrated in  FIG. 2 , the throttle portion  9  is arranged on the positive side in the X-axis direction, i.e., on the downstream side, with respect to the swirl flow generation portion  62 . Moreover, the throttle portion  9  is arranged on a base end portion  123  side as an upper end portion of the analysis column  121 . The throttle portion  9  arranged as described above can throttle the swirl flow when the swirl flow of the air AR generated in the swirl flow generation portion  62  is discharged into the housing  61 . Thus, the flow rate of the air AR can be increased. 
     The throttle portion  9  has multiple through-holes  91  formed to penetrate the throttle portion  9  along the direction of discharging the air AR (the swirl flow). As illustrated in  FIG. 3 , these through-holes  91  are arranged in a honeycomb shape as viewed from an air AR discharge side, i.e., the positive side in the X-axis direction. With such arrangement, the flow rate of the air AR is not necessarily increased by adjustment of the number of rotations of the fan  621 , and the flow rate of the air AR can be easily increased without excess or deficiency while being maintained constant. 
     In the column oven  6 , the air AR can contact the analysis column  121  when passing through the first space  615 , thereby heating the analysis column  121 . At this point, the temperature of the air AR decreases as the air AR passes through the first space  615  (as the air AR flows apart from the heating portion  63 ). However, the flow rate is increased as described above, and therefore, a temperature decrease in the first space  615  can be suppressed as much as possible. Thus, the analysis column  121  can be uniformly heated from the base end portion  123  to the tip end portion  124 . Moreover, by the throttle portion  9 , influence of a swirl flow rotation direction on temperature distribution in the first space  615  can be prevented or reduced. Thus, uneven heating can be prevented, and therefore, the entirety of the analysis column  121  can be more uniformly heated. 
     Moreover, as illustrated in  FIG. 3 , each through-hole  91  is in a hexagonal shape as viewed from the air AR discharge side. A distance L 91  between a pair of opposing surfaces of the hexagonal shape is preferably equal to or greater than 5 mm and equal to or less than 10 mm, and more preferably equal to or greater than 6 mm and equal to or less than 9 mm. With this configuration, a throttle function at each through-hole  91  can be maintained while smooth passage of the air AR can be made. Moreover, in the case of employing such a more preferable numerical range, the throttle portion  9  also functions as a finger guard configured to prevent, e.g., a finger from entering the fan  621 . 
     Depending on the volume of the first space  615 , the total opening area of the through-holes  91  as viewed from the air AR discharge side is, for example, preferably equal to or higher than 60% with respect to the opening area of the fixing port  617 , and more preferably about 75% for decreasing a pressure loss influencing the flow rate of the air AR. 
     The throttle portion  9  includes a plate-shaped member in the present embodiment, and the thickness t 9  thereof is preferably equal to or greater than 5 mm for a rectification effect at a later-described rectification portion  18 . However, in a case where an inclined surface  92  has an inclination angle θ 92  of about 15° for the rectification effect (a louver effect), the thickness t 9  is more preferably about 15 mm for decreasing the pressure loss. 
     Note that a material forming the throttle portion  9  is not specifically limited, and for example, various resin materials are preferably used. The resin material has a lower heat conductivity than that of a metal material, and can prevent removal of heat of the air AR when the air AR passes through each through-hole  91 , for example. 
     As illustrated in  FIG. 2 , an inner peripheral surface of each through-hole  91  has the inclined surfaces  92  inclined with respect to the horizontal direction, i.e., an XY plane. The inclined surfaces  92  are provided on the upper and lower sides in each through-hole  91 . Moreover, each inclined surface  92  has a function as the rectification portion  18  configured to direct the air AR (the swirl flow) throttled by the throttle portion  9  to an analysis column  121  side. Thus, the air AR can smoothly contact the analysis column  121 , and therefore, prompt heating of the analysis column  121  can be performed. 
     A relatively-great degree of the inclination angle θ 92  of each inclined surface  92  with respect to the horizontal direction results in a great pressure loss, and the flow rate of the air AR decreases. For this reason, such an inclination angle θ 92  is preferably about 15°. Moreover, the through-holes  91  may have the same inclination angle θ 92  or different inclination angles θ 92 . In a case where the through-holes  91  have the different inclination angles θ 92 , the inclination angle θ 92  in the upper through-hole  91  can be set greater than the inclination angle θ 92  in the lower through-hole  91 . 
     As described above, in the present embodiment, it is configured such that the throttle portion  9  has the function as the rectification portion  18 . Thus, the number of components can be reduced as compared to a case where the throttle portion  9  and the rectification portion  18  are configured as separated bodies, and therefore, the cost for manufacturing the column oven  6  can be reduced. 
     Note that the throttle portion  9  and the rectification portion  18  may be configured as separated bodies. In this case, the rectification portion  18  is, on the downstream side, preferably arranged adjacent to the throttle portion  9 . 
     The suction port  618  forming part of a suction portion  19  is positioned on a tip end portion  124  side as a lower end portion of the analysis column  121 . 
     Moreover, a protruding piece  619  protruding from the partition wall portion  614  toward a first space  615  side is provided above the suction port  618 . The protruding piece  619  is inclined with respect to the horizontal direction, and a lower portion  619   a  in such an inclination direction is positioned below the tip end portion  124  of the analysis column  121 . Thus, the direction of sucking the air AR into the suction port  618  can be restricted. By such restriction, the air AR flows toward the suction port  618  to flow around the protruding piece  619 , and can sufficiently heat even the tip end portion  124  of the analysis column  121 . Thus, a temperature difference between the base end portion  123  side and the tip end portion  124  side in the analysis column  121  can be eliminated as much as possible, and the analysis column  121  is brought into a state suitable for analysis. 
     As described above, the suction portion  19  has the protruding piece  619  as a restriction portion configured to restrict the direction of sucking the air AR into the suction port  618 . 
     The column oven and the chromatography of the present invention have been described above with reference to the illustrated embodiment, but the present invention is not limited to above. Each portion forming the column oven and the chromatography can be replaced with one having an optional configuration providing a similar function. Moreover, an optional component may be added. 
     Aspects 
     Those skilled in the art understand that the above-described multiple exemplary embodiments are specific examples of the following aspects. 
     A column oven of a first aspect comprises: a hollow housing; an analysis column arranged in the housing and allowing circulation of a mobile phase in the analysis column; a heating portion configured to heat air; a swirl flow generation portion configured to discharge, as a swirl flow, the air heated by the heating portion into the housing; and a throttle portion configured to throttle the swirl flow when the swirl flow is discharged into the housing. The throttle portion has multiple through-holes formed to penetrate the throttle portion along a direction of discharging the swirl flow and arranged in a honeycomb shape as viewed from a swirl flow discharge side. 
     According to a column oven of a first aspect, air can contact an analysis column when passing through a housing, thereby heating the analysis column. At this point, the temperature of the air decreases as the air passes through the housing (as the air flows apart from a heating portion). However, a flow rate is increased by a throttle portion, and therefore, a temperature decrease in the housing can be suppressed as much as possible. Thus, the entirety of the analysis column can be uniformly heated. 
     In a column oven of a second aspect, each through-hole is in a hexagonal shape as viewed from the swirl flow discharge side, and a distance between a pair of opposing surfaces of the hexagonal shape is equal to or greater than 5 mm and equal to or less than 10 mm. 
     According to a column oven of a second aspect, a throttle function at each through-hole  91  can be maintained while smooth passage of air AR is allowed. 
     The column oven of a third aspect further comprises: a holding portion configured to hold the analysis column along a vertical direction. The throttle portion is arranged on an upper end side of the analysis column. 
     According to a column oven of a third aspect, an analysis column can be uniformly heated from an upper end portion to a lower end portion thereof. 
     The column oven of a fourth aspect further comprises: a rectification portion configured to direct the swirl flow throttled by the throttle portion to the analysis column side. 
     According to a column oven of a fourth aspect, air can smoothly contact an analysis column, and therefore, prompt heating of the analysis column can be performed. 
     In a column oven of a fifth aspect, the throttle portion has a function as the rectification portion. 
     According to a column oven of a fifth aspect, the number of components can be reduced as compared to a case where a throttle portion and a rectification portion are configured as separated bodies, and therefore, the cost for manufacturing the column oven can be reduced. 
     In the column oven a sixth aspect, an inner peripheral surface of each through-hole has an inclined surface inclined with respect to a horizontal direction and having the function as the rectification portion. 
     According to a column oven of a sixth aspect, a rectification portion can be provided with a simple configuration at a throttle portion. 
     In a column oven of a seventh aspect, the throttle portion includes a plate-shaped member having a thickness of equal to or greater than 5 mm. 
     According to a column oven of a seventh aspect, in a case where a thickness falls, for example, below the lower limit of the numerical range of the thickness, the distance of passage of air through each through-hole becomes shorter, and for this reason, there is a probability that it is difficult to sufficiently fulfill a rectification function of a later-described rectification portion. Moreover, in a case where the thickness exceeds the upper limit of the numerical range of the thickness, the distance of passage of air through each through-hole becomes longer, and for this reason, there is a probability that a pressure loss is caused to such an extent that it is difficult to sufficiently supply air to a housing. 
     A column oven of an eighth aspect further comprises: a suction portion including a suction port provided on a lower end side of the analysis column and configured to suck the air in the housing and a restriction portion configured to restrict a direction of sucking the air into the suction port. 
     According to a column oven of an eighth aspect, air flows toward a suction port to flow around the suction port in a housing, and therefore, even a lowermost end portion of an analysis column can be sufficiently heated. 
     In a column oven of a ninth aspect, the heating portion heats the air sucked through the suction port. 
     According to a column oven of a ninth aspect, air can circulate in a housing. With this configuration, the air provided to the analysis column and having a decreased temperature can be heated again, and therefore, such air can be promptly increased to a desired temperature. 
     A chromatography of a tenth aspect comprises: the column oven. 
     According to a chromatography of a tenth aspect, air can contact an analysis column when passing through a housing, thereby heating the analysis column. At this point, the temperature of the air decreases as the air passes through the housing (as the air flows apart from a heating portion). However, a flow rate is increased by a throttle portion, and therefore, a temperature decrease in the housing can be suppressed as much as possible. Thus, the entirety of the analysis column can be uniformly heated.