Patent Publication Number: US-9851282-B2

Title: Sample cooling device, and autosampler provided with the same

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a National Stage of International Application No. PCT/JP2013/059545, filed Mar. 29, 2013, the contents of which are incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present invention relates to a sample cooling device for cooling a sample in a sample container that is accommodated in an accommodating chamber, and an autosampler provided with the same. 
     BACKGROUND ART 
     For example, some analysis devices such as a liquid chromatograph are provided with an autosampler for sucking a sample in a sample container by a needle and for automatically analyzing the sample. Depending on the type of sample to be the analysis target, the sample may sometimes have to be cooled from the standpoint of preventing alteration. In such a case, the sample in the sample container may be cooled by using a sample cooling device (for example, see Patent Document 1). 
     Regarding the sample cooling device, a direct cooling type and an air cooling type are known, for example. According to a direct-cooling sample cooling device, for example, a plurality of sample containers are accommodated in a highly thermal conductive rack and the rack is installed in a cooling section so that the sample containers on the rack may be cooled by a cooler such as a Peltier device provided to the cooling section. That is, with the direct-cooling sample cooling device, the cooling section configures an installation section for installing the sample containers. On the other hand, according to an air-cooling sample cooling device, a sample container may be cooled by air, by cooling the air inside an accommodating chamber accommodating the sample container by a cooler. 
     PRIOR ART DOCUMENTS 
     Patent Documents 
     JP 2000-74802 A 
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     With a sample cooling device as described above, moisture in the air inside an accommodating chamber where a sample container is accommodated may be condensed at the time of cooling of a sample, and the moisture may negatively affect analysis of the sample. For example, if moisture is condensed on a sample container at an autosampler, the moisture on the sample container possibly gets mixed in the sample at the time of insertion of a needle into the sample container, thereby changing the concentration of the sample. 
     To suppress such a problem caused by condensation, a sample cooling device disclosed in Patent Document 1 adopts a structure where dehumidification is performed by cooling the air inside the accommodating chamber. Specifically, by causing the set temperature of a dehumidifier section to be near the dew point, the moisture in the air inside the accommodating chamber is condensed at the dehumidifier section, and the absolute humidity inside the accommodating chamber may be reduced. 
     Normally, a packing for maintaining air-tightness is attached to the boundary section of parts forming the accommodating chamber, and air containing moisture may be prevented from flowing into the accommodating chamber from outside the accommodating chamber. However, even with such a configuration, air may sometimes flow into the accommodating chamber from a gap between the parts forming the accommodating chamber. If air containing moisture flows into the accommodating chamber, the air inside the accommodating chamber may not be desirably dehumidified, and problems may be caused due to condensation as described above. 
     Particularly, with a sample cooling device, the temperature inside the accommodating chamber is relatively low, and the pressure inside the accommodating chamber is inclined to become negative. Thus, there is a problem that air may easily flow into the accommodating chamber from the gap between the parts forming the accommodating chamber. Also, air is sometimes made to flow on the outside the accommodating chamber so as to cool a heat generating section (for example, a switching power supply) in the periphery of the sample cooling device, and also in such a case, air may easily flow into the accommodating chamber from the gap between parts forming the accommodating chamber. 
     Moreover, with an autosampler provided with the sample cooling device as described above, a liquid drain port for draining cleaning liquid at the time of cleaning a flow path that is communicated with a needle is sometimes formed to a wall surface of the accommodating chamber. In this case, when liquid is not being drained from the liquid drain port, air containing moisture may flow into the accommodating chamber from outside the accommodating chamber through the liquid drain port. 
     The present invention has been made in view of the above circumstances, and has its object to provide a sample cooling device capable of preventing air containing moisture from flowing into an accommodating chamber from outside the accommodating chamber and of desirably dehumidifying the air inside the accommodating chamber, and an autosampler provided with the same. 
     Means for Solving the Problems 
     A sample cooling device of the present invention is a sample cooling device for cooling a sample in a sample container that is accommodated in an accommodating chamber, the sample cooling device including: a cooling section configured to cool the sample container that is accommodated in the accommodating chamber; a dehumidifier section configured to perform dehumidification by cooling air inside the accommodating chamber; and a blower section configured to supply dehumidified air into the accommodating chamber by sending air into the accommodating chamber from outside the accommodating chamber and causing the air to be cooled by the dehumidifier section. 
     According to such a configuration, with the air sent into the accommodating chamber by the blower section from outside the accommodating chamber, the inside of the accommodating chamber may be placed in a pressurized state. The air inside the accommodating chamber may thereby be caused to flow out of the accommodating chamber through, for example, the gap between the parts forming the accommodating chamber, and air containing moisture may be prevented from flowing into the accommodating chamber through the gap or the like. 
     Also, since air that is sent into the accommodating chamber by the blower section from outside the accommodating chamber is cooled by the dehumidifier section, dehumidified air is supplied into the accommodating chamber, and thus humidity inside the accommodating chamber may be prevented from rising due to the air that is sent in by the blower section. Accordingly, air containing moisture may be prevented from flowing into the accommodating chamber from outside the accommodating chamber, and the air inside the accommodating chamber may be desirably dehumidified. 
     The blower section may send a part of air that is sent from a cooling fan for cooling a heat generating section into the accommodating chamber. 
     According to such a configuration, air may be sent into the accommodating chamber from outside the accommodating chamber by using air that is sent by the cooling fan for cooling a heat generating section. Therefore, since there is no need to separately provide a fan or the like to send air into the accommodating chamber from outside the accommodating chamber, the manufacturing cost may be reduced. 
     The cooling fan may be one for cooling a heat generating section at the dehumidifier section. In this case, since the cooling fan and the dehumidifier section are placed relatively close to each other, a part of the air sent by the cooling fan may be cooled at the dehumidifier section by a simple configuration, and dehumidified air may be supplied into the accommodating chamber. The configuration may thus be simplified, and the manufacturing cost may be further reduced. 
     The dehumidifier section may include a cooling surface for cooling air inside the accommodating chamber. In this case, the blower section may send air from outside the accommodating chamber to near the cooling surface. 
     According to such a configuration, air sent into the accommodating chamber by the blower section from outside the accommodating chamber is sent to near the cooling surface of the dehumidifier section for cooling the air inside the accommodating chamber, and is thus desirably cooled at the cooling surface. Therefore, sufficiently dehumidified air may be supplied into the accommodating chamber, and thus humidity inside the accommodating chamber may be effectively prevented from rising due to the air that is sent in by the blower section. 
     An autosampler of the present invention includes: the sample cooling device; and a suction mechanism configured to suck a sample inside the sample container that is accommodated in the accommodating chamber. 
     Effects of the Invention 
     According to the present invention, with the air sent into the accommodating chamber by the blower section from outside the accommodating chamber, the inside of the accommodating chamber may be placed in a pressurized state, and also by cooling, by the dehumidifier section, the air that is sent into the accommodating chamber by the blower section from outside the accommodating chamber, dehumidified air is supplied into the accommodating chamber, and thus air containing moisture may be prevented from flowing into the accommodating chamber from outside the accommodating chamber, and the air inside the accommodating chamber may be desirably dehumidified. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram showing an example configuration of an autosampler according to an embodiment of the present invention. 
     
    
    
     MODE FOR CARRYING OUT THE INVENTION 
       FIG. 1  is a diagram showing an example configuration of an autosampler according to an embodiment of the present invention. This autosampler may be applied to various analysis devices such as a liquid chromatograph, for example. 
     The autosampler according to the present embodiment includes a sample cooling device  1  for cooling a sample, and a suction mechanism  2  for sucking the sample that is being cooled by the sample cooling device  1 . The sample is contained in a sample container  3  such as a vial, and a plurality of the sample containers  3  may be installed inside the sample cooling device  1  by being held by a rack  4 . The rack  4  is formed of a highly thermal conductive metal, for example. 
     The sample cooling device  1  includes an accommodating chamber  11 , a cooling section  12 , a dehumidifier section  13 , and the like, for example. The accommodating chamber  11  has its wall surface formed of a highly heat insulating material, for example, and the accommodating chamber  11  may be hermetically sealed while accommodating inside the sample container  3  together with the rack  4 . By cooling the sample container  3  that is accommodated in the accommodating chamber  11 , the sample in the sample container  3  may be cooled. 
     The cooling section  12  is for cooling the sample container  3  that is accommodated in the accommodating chamber  11 , and includes a Peltier device  121 , a heat sink fin  122 , an installation section  123 , and the like, for example. The Peltier device  121  is provided in such a way as to partition the inside and the outside of the accommodating chamber  11 , and for example, the heat sink fin  122  is attached on the Peltier device  121 , on the surface on the outside of the chamber (the lower side), and the installation section  123  is attached on the Peltier device  121 , on the surface on the inside of the chamber (the upper side). 
     The installation section  123  is formed of a highly thermal conductive metal, for example, and the rack  4  may be installed above the installation section  123 . The installation section  123  may thereby be cooled by the Peltier device  121 , and the sample container  3  on the rack  4  may be cooled through the installation section  123 . At this time, the heat that is absorbed by the Peltier device  121  from the installation section  123  is radiated outside the accommodating chamber  11  via the heat sink fin  122 . 
     In this manner, in the present embodiment, the cooling section  12  configures the installation section  123  where the sample container  3  is to be installed. That is, the sample cooling device  1  according to the present embodiment is a direct cooling type, and by installing the rack  4  at the cooling section  12 , the sample container  3  on the rack  4  may be cooled. 
     A part of a wall surface of the accommodating chamber  11  forms an opening/closing cover  111  that is to be opened or closed, for example, at the time of installation of the sample container  3  inside the accommodating chamber  11 . The opening/closing cover  111  is of a pullout type, for example, and the rack  4  may easily be installed on the installation section  123  of the cooling section  12  by the installation section  123  being moved forward according to an operation of pulling out the opening/closing cover  111  forward. A packing (not shown) for maintaining air-tightness is attached to the peripheral portion of the opening/closing cover  111 , for example. 
     The dehumidifier section  13  is for performing dehumidification by cooling the air inside the accommodating chamber  11 , and includes a Peltier device  131 , a heat sink fin  132 , an attachment section  133 , a tray  134 , a drainpipe  135 , and the like, for example. The dehumidifier section  13  is provided on the wall surface at the back side of the accommodating chamber  11 , for example. 
     The Peltier device  131  is provided in such a way as to partition the inside and the outside of the accommodating chamber  11 , and for example, the heat sink fin  132  is attached on the Peltier device  131 , on the surface on the outside (the back side) of the chamber, and the attachment section  133  is attached on the Peltier device  131 , on the surface on the inside (the front side) of the chamber. The attachment section  133  is formed of a highly thermal conductive metal, for example, and as with the heat sink fin  132 , it may be formed into a fin shape where a plurality of metal plates are arranged in parallel. In this case, the plurality of metal plates forming the attachment section  133  are provided each preferably extending in the vertical direction. 
     At the time of dehumidification of the inside of the accommodating chamber  11 , the attachment section  133  is cooled by the Peltier device  131 . The surface of the attachment section  133  forms a cooling surface  130  for cooling the air inside the accommodating chamber  11 . Specifically, by cooling the temperature of the cooling surface  130  to be around the dew point (for example, around 0° C.), moisture in the air inside the accommodating chamber  11  may be made to condense on the cooling surface  130  (the attachment section  133 ), and the absolute humidity inside the accommodating chamber  11  may be reduced. At this time, the heat absorbed by the Peltier device  131  from the attachment section  133  is radiated outside the accommodating chamber  11  through the heat sink fin  132 . 
     The tray  134  is for collecting water produced at the time of dehumidification, and is enabled to receive water running down on the attachment section  133  by being arranged below the attachment section  133 . Water collected in the tray  134  is drained outside the accommodating chamber  11  via the drainpipe  135 . 
     A cooling fan  14  is provided on the outside of the accommodating chamber  11 . In this example, by being attached on the outer wall at the back side of the accommodating chamber  11 , the cooling fan  14  is provided near the dehumidifier section  13 . The heat sink fin  132  of the dehumidifier section  13  is exposed to the outside from the wall surface at the back side of the accommodating chamber  11 , and the cooling fan  14  is provided below the heat sink fin  132 . 
     In the present embodiment, an air passage  15  for letting air pass in the front-back direction is formed below the accommodating chamber  11 . The heat sink fin  122  of the cooling section  12  is exposed to the air passage  15  from the wall surface on the lower side of the accommodating chamber  11 , and the cooling fan  14  is provided behind the heat sink fin  122  (behind the air passage  15 ). 
     The cooling fan  14  includes an air inlet port  141 , an air outlet port  142 , a blade  143 , and the like. During operation of the sample cooling device  1 , the air is drawn in from the air inlet port  141  and the air is blown out from the air outlet port  142  by rotation of the blade  143 . In this example, the cooling fan  14  is arranged in such a way that the air inlet port  141  is inclined at a predetermined angle (for example, about 45°) with respect to the vertical direction. 
     Thus, as shown by arrows in  FIG. 1 , a flow F 1  of air flowing downward from the side of the heat sink fin  132  of the dehumidifier section  13  arranged above the cooling fan  14 , and a flow F 2  of air flowing toward the back from the side of the heat sink fin  122  of the cooling section  12  arranged before the cooling fan  14  are generated. With the generation of such flows F 1  and F 2  of air, the heat sink fins  122  and  132  as heat generating sections may be cooled. 
     The heat sink fin  132  of the dehumidifier section  13  is covered with a casing  136 . A vent hole  137  for passing air to the heat sink fin  132 , and a guide passage  138  for guiding the air which has passed through the heat sink fin  132  to the cooling fan  14  are formed to the casing  136 . Thus, the flow F 1  of air from the side of the heat sink fin  132  of the dehumidifier section  13  to the cooling fan  14  may be desirably generated. Additionally, this casing  136  may be shaped in other ways or may be omitted. 
     In the present embodiment, a communicating pipe  16  for communicating the outside and the inside of the accommodating chamber  11  is provided to the sample cooling device  1 . One end of the communicating pipe  16  is connected to the air outlet port  142  of the cooling fan  14 . On the other hand, the other end of the communicating pipe  16  is connected to the inside of the accommodating chamber  11 . The cooling fan  14  and the communicating pipe  16  thereby form a blower section  100  for sending a part of the air sent from the cooling fan  14  into the accommodating chamber  11 . 
     As shown in  FIG. 1 , the other end of the communicating pipe  16  is arranged inside the accommodating chamber  11 , near the dehumidifier section  13 . Accordingly, the blower section  100  may send the air from outside the accommodating chamber  11  to near the cooling surface  130  of the dehumidifier section  13 . In this example, the air that is sent from the cooling fan  14  side through the communicating pipe  16  is blown toward the inner wall side of the accommodating chamber  11  from the other end of the communicating pipe  16  and is dispersed, and the dispersed air is cooled by the cooling surface  130  of the dehumidifier section  13 . 
     A hood member  101  is provided inside the accommodating chamber  11 , for desirably guiding the air that is blown out from the other end of the communicating pipe  16  to the side of the attachment section  133  (the cooling surface  130 ) of the dehumidifier section  13 . This hood member  101  is provided in such a way as to cover a part (for example, the upper side) of the attachment section  133  of the dehumidifier section  13 , and air may thereby be guided desirably to between the plurality of metal plates forming the attachment section  133 , and cooling may be efficiently performed. Additionally, this hood member  101  may be shaped in other ways or may be omitted. 
     As described, according to the present embodiment, by sending air into the accommodating chamber  11  by the blower section  100  from outside the accommodating chamber  11 , and cooling the air by the dehumidifier section  13 , dehumidified air may be supplied to the inside of the accommodating chamber  11 . At this time, with the air sent into the accommodating chamber  11  by the blower section  100  from outside the accommodating chamber  11 , the inside of the accommodating chamber  11  may be placed in a pressurized state. The air inside the accommodating chamber  11  may thereby be caused to flow out of the accommodating chamber  11  through, for example, the gap between the parts forming the accommodating chamber  11 , and air containing moisture may be prevented from flowing into the accommodating chamber  11  through the gap or the like. 
     Also, since air that is sent into the accommodating chamber  11  by the blower section  100  from outside the accommodating chamber  11  is cooled by the dehumidifier section  13 , dehumidified air is supplied into the accommodating chamber  11 , and thus humidity inside the accommodating chamber  11  may be prevented from rising due to the air that is sent in by the blower section  100 . Accordingly, air containing moisture may be prevented from flowing into the accommodating chamber  11  from outside the accommodating chamber  11 , and the air inside the accommodating chamber  11  may be desirably dehumidified. 
     Especially, with the present embodiment, air may be sent into the accommodating chamber  11  from outside the accommodating chamber  11  by using air that is sent by the cooling fan  14  for cooling a heat generating section (for example, the heat sink fins  122 ,  132  and the like). Therefore, since there is no need to separately provide a fan or the like to send air into the accommodating chamber  11  from outside the accommodating chamber  11 , the manufacturing cost may be reduced. 
     As in the present embodiment, in the case where the cooling fan  14  is for cooling a heat generating section (the heat sink fin  132 ) at the dehumidifier section  13 , the cooling fan  14  and the dehumidifier section  13  are placed relatively close to each other. Accordingly, a part of the air sent by the cooling fan  14  may be cooled at the dehumidifier section  13  by a simple configuration, and dehumidified air may be supplied into the accommodating chamber  11 . The configuration may thus be simplified, and the manufacturing cost may be further reduced. 
     Also, according to the present embodiment, air sent into the accommodating chamber  11  by the blower section  100  from outside the accommodating chamber  11  is sent to near the cooling surface  130  of the dehumidifier section  13  for cooling the air inside the accommodating chamber  11 , and is thus desirably cooled at the cooling surface  130 . Therefore, sufficiently dehumidified air may be supplied into the accommodating chamber  11 , and thus humidity inside the accommodating chamber  11  may be effectively prevented from rising due to the air that is sent in by the blower section  100 . 
     The suction mechanism  2  is provided with a needle  21  that is to be inserted into the sample container  3 . The needle  21  is configured to be able to move in the horizontal and vertical directions, and is inserted into the sample container  3  by being horizontally moved to above the sample container  3  and then moved downward, and the sample inside the sample container  3  is sucked from the needle  21 . Then, the needle  21  is moved upward to be removed outside the sample container  3 , and is horizontally moved to a sample injection port  22 . Then, the sample sucked out from the sample container  3  is injected into the sample injection port  22 , and automatic supply of a predetermined amount of sample for analysis is thereby enabled. 
     According to an autosampler provided with the sample cooling device  1  of the present embodiment, a liquid drain port (not shown) for draining cleaning liquid at the time of cleaning a flow path that is communicated with the needle  21  is formed to a wall surface of the accommodating chamber  11 . In this case, when liquid is not being drained from the liquid drain port, air containing moisture may flow into the accommodating chamber  11  from outside the accommodating chamber  11  through the liquid drain port. 
     However, as in the present embodiment, with a configuration where the inside of the accommodating chamber  11  is to be placed in a pressurized state by air being sent into the accommodating chamber  11  by the blower section  100  from outside the accommodating chamber  11 , it is possible to prevent air containing moisture from flowing into the accommodating chamber  11  from outside the accommodating chamber  11  through the liquid drain port. 
     The embodiment above describes a direct-cooling sample cooling device  1  where the cooling section  12  configures the installation section  123  for installing the sample container  3 . However, such a configuration is not restrictive, and the present invention may also be applied to an air-cooling sample cooling device which cools the sample container  3  by air. 
     The sample container  3  is not limited to be cooled while being held by the rack  4 , and it may also be cooled while being directly installed in the installation section  123 , for example. Also, the Peltier device  121  for cooling the sample container  3  at the cooling section  12 , and the Peltier device  131  for cooling the air at the dehumidifier section  13  are both replaceable by a different cooler. 
     The blower section  100  is not limited to be configured from the cooling fan  14  and the communicating pipe  16 , and may adopt various other configurations. For example, a configuration where a device capable of sending air into the accommodating chamber  11  from outside the accommodating chamber  11  at a predetermined air pressure is separately provided is also possible. In this case, a configuration where air that is dehumidified in advance is sent into the accommodating chamber  11  is also possible. 
     Also, in the embodiment described above, the cooling fan  14  for cooling the heat generating section (the heat sink fin  132 ) of the dehumidifier section  13  and the heat generating section (the heat sink fin  122 ) of the cooling section  12  configures the blower section  100 , but the blower section  100  may alternatively be configured from a cooling fan for cooling one of the heat generating sections of the dehumidifier section  13  and the cooling section  12 . Also, the blower section  100  may be configured from a cooling fan for cooling a heat generating section other than the heat generating sections of the dehumidifier section  13  and the cooling section  12 . 
     In the case of sending air into the accommodating chamber  11  from outside the accommodating chamber  11  by using various fans, a configuration where a part of the air that is sent to the air inlet port side is sent to the accommodating chamber  11  is also possible, in addition to a configuration as described above where a part of the air that is blown out from the air outlet port side is sent into the accommodating chamber  11 . 
     Furthermore, it is possible to send dehumidified air into the accommodating chamber  11  by providing a desiccant such as silica gel in a flow path for sending air into the accommodating chamber  11  (for example, in the communicating pipe  16 ). As a configuration for sending dehumidified air into the accommodating chamber  11  as described above, a configuration where a mechanism for cooling the air that is to be sent into the accommodating chamber  11 , such as a desiccating mechanism, is provided in a flow path for sending air into the accommodating chamber  11 , instead of the desiccant, is also possible. 
     Any configuration is allowed as long as air that is to be sent into the accommodating chamber  11  by the blower section  100  from outside the accommodating chamber  11  is cooled and dehumidified by the dehumidifier section  13  before being supplied into the accommodating chamber  11 , and the configuration of the embodiment described above where air is blown toward the inner wall side of the accommodating chamber  11  from the other end of the communicating pipe  16  is not restrictive. 
     DESCRIPTION OF REFERENCE SIGNS 
       1  sample cooling device 
       2  suction mechanism 
       3  sample container 
       4  rack 
       11  accommodating chamber 
       12  cooling section 
       13  dehumidifier section 
       14  cooling fan 
       15  air passage 
       16  communicating pipe 
       21  needle 
       22  sample injection port 
       100  blower section 
       101  hood member 
       111  opening/closing cover 
       121  Peltier device 
       122  heat sink fin 
       123  installation section 
       130  cooling surface 
       131  Peltier device 
       132  heat sink fin 
       133  attachment section 
       134  tray 
       135  drainpipe 
       136  casing 
       137  vent hole 
       138  guide passage 
       141  air inlet port 
       142  air outlet port 
       143  blade