Patent Publication Number: US-2018038881-A1

Title: Sample transport apparatus

Description:
CLAIM OF PRIORITY 
     The present application claims priority from Japanese patent application JP 2013-264590 filed on Dec. 20, 2013, the content of which is hereby incorporated by reference into this application. 
     BACKGROUND 
     Technical Field 
     The present invention relates to a sample transport apparatus suited to transporting samples between a plurality of inspection apparatuses. 
     Background Art 
     In recent years, a variety of types of sample inspection apparatuses have been introduced into hospitals and the like to promote automation of sample inspection. Examples of sample inspection apparatuses include sample processing apparatuses, biochemical analyzers, immunoassay apparatuses, and sample accommodating apparatuses. In addition, the sample inspection apparatuses include not only single-module apparatuses but also apparatuses that are obtained by combining a plurality of modules. 
     RELATED ART DOCUMENTS 
     Patent Documents 
     
         
         Patent Document 1: International Publication No. WO2011/040197A 
         Patent Document 2: JP 2003-293494 A 
       
    
     SUMMARY 
     The most part of the outer periphery of a sample transport apparatus, excluding an opening portion used for transporting samples, is surrounded by a housing. Therefore, in maintenance of the sample transport apparatus, the housing should be removed irrespective of what operation is to be performed. Thus, many hours would be required for the operation. In addition, in the existing sample transport apparatuses, accommodation of component parts into housings is prioritized, so that zoning in which maintenance should be taken into consideration can be insufficient. Therefore, when wires accommodated in the housing are arranged in a complex manner, it will take a long time to reach a desired wire. 
     In order to solve the aforementioned problem, structures recited in the claims are adopted, for example. Although this specification includes a plurality of means for solving the aforementioned problem, there is provided, as one example, a sample transport apparatus including (1) a housing, (2) at least one transport line stage accommodated in the housing and including first and second transport lines, each of the first and second transport lines being configured to transport sample holders each capable of holding at least one sample along a side wall of the housing along a long-side direction, (3) a drive mechanism accommodated in the housing, the drive mechanism being configured to transport the sample holders along the first and second transport lines, and (4) wires accommodated in the housing and connected to at least the drive mechanism, in which the first transport line and the second transport line of the transport line stage are arranged in parallel along a long-side side face of the housing, and a first distance between the first transport line and the long-side side face that is adjacent the first transport line is shorter than a second distance between the first transport line and the second transport line. 
     According to the present invention, a sample transport apparatus that can accommodate component parts in a compact manner and only requires easy maintenance can be implemented. Other problems, structures, and advantages will become apparent from the following description of embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view showing the appearance structure of a sample inspection system. 
         FIG. 2  is a view showing exemplary assembly of a sample transport apparatus. 
         FIG. 3  is an exploded perspective view showing an exemplary structure of a sample transport apparatus without a branch path. 
         FIG. 4  is a view showing an exemplary cross-sectional structure cut along a line perpendicular to a long-side direction (Example 1). 
         FIG. 5  is a view showing an exemplary cross-sectional structure cut along a line perpendicular to a long-side direction (Example 2). 
         FIG. 6  is a plan view showing an exemplary structure of a sample transport apparatus for junction. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the embodiments of the present invention are not limited to those described below, and various modifications and variations are possible within the scope and spirit of the invention. In addition, in all drawings used for the description, identical members are, in principle, denoted by identical reference numbers, and repeated description thereof will be omitted. 
     [Exemplary Appearance of Sample Inspection System] 
       FIG. 1  shows an exemplary appearance structure of a sample inspection system. The sample inspection system herein is an exemplary system that has a plurality of sample inspection apparatuses connected together with dedicated transport channels (i.e., sample transport apparatuses). The scale of the sample inspection system and the combination of sample inspection apparatuses that constitute the system may differ in accordance with an installation place or needs of customers. In this specification, a sample refers to a target to be inspected that is egested or taken from a human body, and includes, for example, blood, urine, feces, tissues, and cells. 
     The sample inspection system shown in  FIG. 1  includes a sample processing apparatus  100 , a sample analyzer (i.e., biochemical analyzer)  110 , a sample analyzer (i.e., an apparatus obtained by connecting a biochemical analyzer and an immunoassay apparatus)  120 , a sample accommodating apparatus (i.e., refrigerator)  130 , five sample transport apparatuses  140 , and two sample transport apparatuses  150  for connection. 
     The inspection processing apparatus  100  in this embodiment includes, for example, a loading module for installing a loaded sample onto an inspection rack (hereinafter referred to as a “sample holder”), a storage module for taking out the sample from the sample holder, a processing module (e.g., an centrifugal module, an uncapping module, a dispensing module, a barcode sticking module, or a sample classification module) for executing a predetermined process on the sample and/or the sample holder, a rack stocker for supplying and collecting sample holders, and a control unit (not shown). The sample processing apparatus  100  has extended main transport lines, each of which transports sample holders each holding at least one sample in the long-side direction such that the main transport line crosses the module. 
     In this embodiment, main transport lines are arranged in two stages including upper and lower stages. In each stage, two main transport lines that transport samples in opposite directions are arranged in parallel. It should be noted that the main transport lines on the lower stage side are adapted to transport empty sample holders from which samples have been taken out. Needless to say, the main transport lines may also be arranged in a single stage or three or more stages. The specifications, such as the dimensions, mounting positions, and mounting heights of the main transport lines are made common to all apparatuses that constitute the sample inspection system (in the case of  FIG. 1 , the sample analyzer  110 , the sample analyzer  120 , the sample accommodating apparatus  130 , the sample transport apparatuses  140 , and the sample transport apparatuses  150  for junction). 
     It should be noted that the sample analyzer  110  is a stand-alone biochemical analyzer; the sample analyzer  120  is an apparatus obtained by connecting a biochemical apparatus and an immunoassay apparatus in series in the transport direction; and the sample accommodating apparatus  130  is a large-tower-type accommodating apparatus used for refrigeration storage of samples. 
     The sample transport apparatus  140  is a specialized transport apparatus for transporting samples and/or sample holders in the long-side direction, and basically has no other functional portions than the transport function. The sample transport apparatus  140  includes in its housing the aforementioned main transport lines, a drive mechanism (which includes a belt conveyor and its driving motor) for moving sample holders along the main transport lines, a power supply unit that supplies power to at least the motor and the like of the drive mechanism, and wires such as power lines and control signal lines. 
       FIG. 2  shows an exemplary appearance of the sample transport apparatus  140 . In  FIG. 2 , the sample transport apparatus  140  is connected in a T-shape via the sample transport apparatus  150  for junction. The sample transport apparatus  140  shown in  FIG. 2  accommodates transport lines that extend in the long-side direction, a pair of right and left housings (panels)  141  forming the long-side side faces, a transport line cover  142  that covers an opening portion at the top of the housings, a base substrate  143  that supports the housings  141  and an internal structure (not shown), openable/closable doors  144  forming the long-side side faces of the sample transport apparatus  140  together with the housings  141 , and legs  145  attached to the bottom of the base substrate  143 . 
     The sample transport apparatus  140  is based on the premise that it will be connected to another sample transport apparatus or a sample inspection apparatus, and thus has open opposite ends in the long-side direction. That is, the sample transport apparatus  140  has a cylindrical appearance whose cross section is approximately rectangular in shape. In this embodiment, one of two types of units that have common component parts other than the transport line length (that is, the length of the housing in the long-side direction) is used for the sample transport apparatus  140 . In this embodiment, the transport line length is supposed to be 600 mm or 900 mm. 
     The sample transport apparatus  150  for junction is a transport-only apparatus that can connect to the sample transport apparatus  140  and/or the sample inspection apparatus in a plurality of directions. Therefore, as with the sample transport apparatus  140 , the sample transport apparatus  150  for junction basically has no other functions than the transport function. Thus, the sample transport apparatus  150  for junction includes main transport lines, a drive mechanism (which includes a belt conveyor and its driving motor) that moves sample holders along the main transport lines, a power supply unit that supplies power to at least the motor and the like of the drive mechanism, and wires such as power lines and control signal lines. 
     However, the sample transport apparatus  150  for junction has, in addition to the transport mechanism for taking in and out sample holders to/from the sample transport apparatus  140  or a sample inspection apparatus, which is connected in series with the sample transport apparatus  150  for junction in the long-side direction, a transport mechanism for taking in and out sample holders to/from the sample transport apparatus  140  connected at a predetermined mounting angle, sub-transport lines for transferring sample holders from one of the pair of main transport lines arranged in parallel to the other main transport line, a stopper used to individually switch the transport directions of sample holders at a plurality of branch points in the transport direction, and a direction changing mechanism. 
     The sample transport apparatus  150  for junction comes in various shapes, for example, those for T-shape connection, L-shape connection, and Y-shape connection. The sample transport apparatus  150  for junction shown in  FIG. 2  is the apparatus for T-shape connection. It should be noted that when transport to one of the sample transport apparatuses  140  that extend right and left from the long-side side faces of the sample transport apparatus  150  for junction is not necessary, the sample transport apparatus  150  for junction for L-shape connection is used. Needless to say, the sample transport apparatus  150  for junction for T-shape connection can also be used as a sample transport apparatus  150  for junction for L-shape connection as long as one of the two opening portions formed on the long-side side faces of the sample transport apparatus  150  for junction for T-shape connection is covered. 
     The sample transport apparatus  150  for junction includes a rectangular housing  151  for accommodating main-transport lines that extend in the long-side direction and sub-transport lines that extend in the short-side direction, and a transport line cover  152  that covers an opening portion at the top of the housing. In  FIG. 2 , the housing  151  of the sample transport apparatus  150  for junction is a box-shaped housing whose bottom face is near a floor surface (i.e., installation surface), and has four height adjustment legs  153  at the bottom face. 
     [Exemplary Structure of Sample Transport Apparatus] 
     An exemplary internal structure of the sample transport apparatus  140  will be described with reference to  FIGS. 3 to 4 .  FIG. 3  is an exploded perspective view of the sample transport apparatus  140 , and  FIG. 4  is a cross-sectional view of the sample transport apparatus  140  cut along a line perpendicular to the transport direction. In this embodiment, the housing of the sample transport apparatus  140  has arranged therein two transport line stages each including two (right and left) transport lines. Samples are transported on the right-hand side. In this embodiment, the transport line stage on the upper stage side is used only for transporting sample holders  161  holding samples  160  (e.g., test tubes that accommodate sample solutions), while the transport line stage on the lower stage side is used only for transporting sample holders  161  not having the samples  160  mounted thereon (i.e., empty). In  FIG. 3 , the transport line stages are shown with front transport lines of the two (upper and lower) stages taken out from the housing. It should be noted that a member on the flat plate depicted at the top of the two (upper and lower) stages of transport lines is a right-left connecting plate  225  used to prevent dust and connect transport lines. 
     The number of transport line stages may be either one or three or more. When the number of transport line stages is three or more, a plurality of transport line stages for use in transporting samples  160  may be provided, or a plurality of transport line stages for use in transporting empty sample holders  161  may also be provided. In this embodiment, a mechanism for transferring the sample holders  161  between the upper and lower transport line stages (i.e., a mechanism for transferring the sample holders  161  from the upper stage side to the lower stage side and/or from the lower stage side to the upper stage side) is mounted on the sample processing apparatus  100  ( FIG. 1 ), for example. Such a mechanism is common, and an example thereof is described in, for example, Patent Literature 1. 
     In this embodiment, as the two transport line stages are provided, two shelf boards (i.e., an upper-stage shelf board  201  and a lower-stage shelf board  202 ) are arranged in the housing. The length of the long side of each of the two shelf boards is substantially equal to the length of the housing  141  in the long-side direction. The center of each of the upper-stage shelf board  201  and the lower-stage shelf board  202  in a rectangular shape is provided with an opening to pass wire cables and the like therethrough. The opening has a size that is necessary to pass control lines and power lines accommodated in the housing therethrough. Although  FIG. 3  shows an example in which one opening is provided, the number of openings may be more than one. 
     The lower-stage shelf board  202  is attached to the base substrate  143  via posts  203 . In this embodiment, a pair of posts  203  are arranged at opposite ends in the long-side direction. A height adjustment mechanism  204  formed of a height adjustment screw or the like is arranged at the attachment portion between the posts  203  and the base substrate  143 . An operating portion of the height adjustment mechanism  204  is provided on the bottom face side of the base substrate  143 . Therefore, an operator is able to operate the operating portion of the height adjustment mechanism  204  in standing position, so as to adjust the installation height of the transport lines. It should be noted that the operating portion of the height adjustment unit  204  may also be provided in the housing. 
     One of the long sides of each openable/closable door  144  is rotatably attached to the base substrate  143 . That is, each openable/closable door  144  is attached to the base substrate  143  so that it can be opened and closed in the vertical direction. When the openable/closable door  144  is opened and closed in the vertical direction, space that is needed to open and close the door can be reduced. It should be noted that the sample transport apparatus  140  has an engaging claw and a lock mechanism (not shown) to keep the openable/closable door  144  closed. Herein, the openable/closable door  144  forms a part of the bottom side face or the bottom of the sample transport apparatus  140 . 
     In this embodiment, wires drawn through the openings, which are provided in the upper-stage shelf board  201  and the lower-stage shelf board  202 , are accommodated in the space surrounded by the bottom-stage shelf board  202 , the base substrate  143 , and the openable/closable doors  144 . For example, power lines  205  for the belt driving motor, power lines  206  for the stopper driving motor, and signal lines  207  to  209  are accommodated. It should be noted that the wires accommodated in the space also include wires that just pass through the inside of the sample transport apparatus  140  in the longitudinal direction. At least some of such wires are connected to other apparatuses (e.g., the sample transport apparatus  140 , the sample transport apparatus  150  for junction, and the sample inspection apparatus) that are connected to the sample transport apparatus  140 . 
     An operator is able to easily access a wire that is necessary only by opening the openable/closable door  144 . In addition, providing the openable/closable door  144  allows some of maintenance to be conducted without removing the housing  141 , which results in improved operation efficiency. It is also possible to use an apparatus structure that uses a member detachable from the base substrate  143  and the lower-stage shelf board  202  instead of providing the openable/closable doors  144 . 
     Power units  210  for supplying power to the drive mechanism in the transport line stage on the lower stage side are arranged on the upper face of the lower-stage shelf board  202 . In this embodiment, the power units  210  are arranged for the right and left transport lines, respectively. Post members  211  for supporting the upper-stage shelf board  201  are fixed to the opposite ends of the lower-stage shelf board  202  in the long-side direction. In addition, the lower-stage shelf board  202  has fixed thereto fixtures  213  for fixing plates for mounting transport lines (hereinafter referred to as “transport line mounting plates”)  212  perpendicularly to the upper face of the lower-stage shelf board  202 . Herein, a pair of right and left transport line mounting plates  212  are attached across the short-side width of the upper-stage shelf board  201 . 
     A transport line is arranged on the outer side of the transport line mounting plates  212  (i.e., a side that faces the housing  141 ). Meanwhile, various drive mechanisms (e.g., a belt driving motor  220  and a stopper driving motor  221 ) are arranged on the inner side of the transport line mounting plate  212  (i.e., a side that faces the other transport line in the same stage). Herein, the transport line is formed by guide frames  222  that guide the opposite side faces of the sample holder  161  and a transport belt  223  that forms the bottom of the space sandwiched between the guide frames  222 . The transport belt  223  is a ring-like member made of resin, rigid rubber, or the like. The guide path of the transport belt  223  is determined by the arrangement of a guide pin  224 , which protrudes outward from the transport line mounting plate  212 , and a belt drive axis  226 . The belt drive axis  226  is integrally attached to the drive axis of the belt driving motor  220 . Rotation of the belt drive axis  226  causes the transport belt  223  to move in one direction. With the movement of the transport belt  223  along the guide path, the sample holder  161  that is put on the surface of the transport belt  223  is transported in one direction along the guide frames  222 . 
     As described previously, in this embodiment, wires, drive mechanisms, and the like are disposed in the interior space that is sandwiched between the pair of right and left transport lines. Thus, the distance (e.g., first distance) between the outer side face of each transport line and the housing  141  can be made shorter than the distance (e.g., second distance) between the pair of right and left transport lines. For example, provided that the horizontal width (e.g., short-side length) of the sample transport apparatus  140  is 250 mm, the maximum diameter of the sample holder  161  is 30 mm, and the distance from the guide frame  222  to the adjacent housing  141  is 15 mm, the distance between the pair of right and left transport lines is 160 mm. This satisfies the aforementioned relationship. 
     The upper-stage shelf board  201  also has fixed thereto fixtures  213  for mounting transport line mounting plates  212  perpendicularly to the upper face of the upper-stage shelf board  201 . The structure of the transport line stage on the upper stage side is the same as that of the transport line stage on the lower stage side. That is, transport lines are also arranged on the outer sides of the pair of right and left transport line mounting plates  212  that form the transport line stage on the upper stage side, and a variety of types of drive mechanisms are arranged on the inner side thereof. It should be noted that the upper end portions of the pair of right and left transport line mounting plates  212  are connected with a right-left connecting plate  225 . The right-left connecting plate  225  serves the purpose of increasing rigidity by connecting the upper ends of the right and left transport line mounting plates  212 , and also serves the purpose of avoiding intrusion of dust or dirt by covering the opening portion formed between the right and left transport line mounting plates  211 . 
     As shown in  FIG. 4 , in this embodiment, drive mechanisms and wires with relatively high weights can be arranged in an integrated manner around the center of the sample transport apparatus  140  in the short-side direction. Consequently, the center of gravity of each member can be positioned on the inner side than the attachment portions of the legs  145 , whereby it becomes possible to prevent the sample transport apparatus  140 , which is supported by the legs  145 , from falling down easily even when the center of gravity is located at a high level from the floor surface. 
     Although this embodiment illustrates an example in which the upper end of each leg  145  is fixed to the base substrate  143  as shown in  FIG. 4 , it is also possible to adopt a structure in which each leg  145  is fixed to the lower-stage shelf board  202  as shown in  FIG. 5 . In the structure of  FIG. 5 , the openable/closable doors  144  may be attached to the leg  145  in an openable/closable manner, for example. However, in the exemplary structure of  FIG. 5 , it is impossible to provide a height adjustment mechanism at the height where the height adjustment mechanism can be operated in standing position as the lower-stage shelf board  202  is directly fixed to the openable/closable doors  144 . 
     A structure that is specific to the sample transport apparatus  150  for junction will be described with reference to  FIG. 6 . The basic structure of the sample transport apparatus  150  for junction is similar to the internal structure of the sample transport apparatus  140  without a branch path. That is, in this embodiment, transport lines on the upper stage side are used for transporting samples, while transport lines on the lower stage side are used only for transporting sample holders. 
     One of the characteristic structures of the sample transport apparatus  150  for junction is that the housing  151  on the long side is provided with openings for connection purposes. In the case of the apparatus for T-shape connection, each of the right and left sides of the housing  151  is provided with an opening, while in the case of the apparatus for L-shape connection, only the connection target side of the housing  151  is provided with an opening. In the opening portion, transfer of the samples  160  and the sample holders  161  is executed between the main transport line of the sample transport apparatus  150  for junction and the main transport line of the connected apparatus. 
     Another characteristic structure of the sample transport apparatus  150  for junction is that sub-transport lines  230  for forming a loop channel are arranged around opposite ends of the pair of right and left transport lines. The sub-transport lines  230  also include guide frames  222 , a transport belt  223  that forms the bottom of the transport lines, a belt driving motor  220 , and a stopper driving motor  221  as with the main transport lines. 
     A stopper mechanism, which is a mechanism common to each of the sample transport apparatus  140  and the sample transport apparatus  150  for junction, is arranged on each transport line. The stopper mechanism includes a stopper driving motor  221  and two stop plates  231  and  232  arranged apart from each other by approximately the diameter of the sample holder  161  in the transport direction. Needless to say, the stopper driving motor  221  is arranged in the space provided between the pair of right and left main transport lines. 
     Each of the stop plates  231  and  232  has a rotation axis that is parallel with the transport direction, and is rotated about the rotation axis. A cutout is formed in a part of the circumference of each of the stop plates  231  and  232  that are in approximate disk shape. When the cutout is located on the side of the guide frame  222 , the sample holder  161  can pass without stopping. Meanwhile, when portions other than the cutout are located on the side of the guide frame  222 , the sample holder  161  is stopped by the stop plates that stick out to the inside of the transport line. 
     The stop mechanism includes the two stop plates  231  and  232  in order to surely separate only one of the plurality of sample holders  161  transported along the transport line. The separation operation is executed in the following procedures. First, the channel is closed with the stop plate on the downstream side, so that the sample holder  161  is stopped. Next, the channel is closed with the stop plate on the upstream side. Accordingly, only one of the sample holders  161  is separated between the two stop plates  231  and  232 . After that, only the stop plate on the downstream side is opened to feed only one of the sample holders  161 , which has been separated, toward the downstream side. Further, the stop plate on the downstream side is closed and the stop plate on the upstream side is opened, so that a next sample holder  161  is stopped between the two stop plates  231  and  232 . After that, the aforementioned operation is repeated. 
     Another mechanism that is specific to the sample transport apparatus  150  for junction is a direction changing mechanism. The direction changing mechanism includes a direction changing arm  233  and a direction changing arm driving motor  234 . The direction changing mechanism is arranged at an intersection of two transport lines with different transport directions. It should be noted that the direction changing mechanism is arranged at a portion that switches between discharge to a transport line of another apparatus connected to the sample transport apparatus  150  for junction and transport within the sample transport apparatus  150  for junction. In addition, the direction changing mechanism is arranged at a portion that switches between transport on a main transport line and transport on a sub-transport line. 
     A movable end (i.e., end portion) of the direction changing arm  233  has a curved shape. In this embodiment, the rotation axis of the direction changing arm driving motor  234  is mounted in parallel with the main transport line. The direction changing arm  233  allows switching of the transport direction of the sample  160  that moves on the main transport line. 
     It should be noted that in this embodiment, an RFID (Radio Frequency IDentification) (not shown) is arranged at the bottom of the sample holder  161 . A sensor (not shown) is arranged on the upstream side of the direction changing arm  233  in the transport direction so that information on the RFID is read by the sensor. The read information on the RFID is processed by a processor (not shown) so that a direction in which the individual sample holder  161  should be transported is determined. The processor, on the basis of the determination result, controls the drive of the direction changing arm driving motor  234  and transports the sample holder  161  in an appropriate direction. 
     It should be noted that in order to allow the sample holder  161  to be transferred between the sample transport apparatus  150  for junction and an apparatus connected to the long-side side face of the sample transport apparatus  150  for junction, the shortest distance between the main transport line in the sample transport apparatus  150  for junction and the housing  141  is designed to be within a half the maximum diameter of the transported sample holder  161 . For example, when the maximum diameter of the sample holder  161  is 30 mm, the distance between the guide frame  222  and the housing  141  is set to less than or equal to 15 mm. 
     CONCLUSION 
     As described above, in this embodiment, the distance (i.e., second distance) between a pair of right and left main transport lines is formed wider than the distance (i.e., first distance) between each main transport line and the housing  141 . Therefore, a compact sample transport apparatus, which has a drive mechanism, a power supply unit, wires, and the like arranged in the space formed between a pair of right and left main transport lines, can be implemented. In addition, according to such a structure, the center of gravity of the sample transport apparatus can be positioned around the center of the short-side direction. Thus, the sample transport apparatus will less easily fall down even when the position of the center of gravity of the apparatus is at a high level. 
     In this embodiment, a wire accommodating portion that integrally accommodates a variety of wires is provided on a further lower-stage side than the transport line stages. Thus, approach to wires in the maintenance operation becomes easier. Further, in this embodiment, the openable/closable doors  144  that allow access to the wire accommodating portion from the outside are provided below the housing  141 . Thus, it is possible to eliminate the necessity to remove all housing component parts each time maintenance is performed. That is, when just maintenance of wires is performed, it is not necessary to remove the housing to access the wires. Thus, the operation time can be reduced by that amount. It should be noted that the openable/closable doors  144  in this embodiment form a part of the lower side wall or the bottom face of the housing  141  and open in the vertical direction. Thus, space that is needed to open the doors can be reduced. 
     In addition, in this embodiment, as multiple stages of transport lines are arranged in the housing  144 , a number of samples  160  and/or sample holders  161  can be transported at a time. Further, when a transport line stage on which sample holders  161  holding samples  160  are transported is separated from a transport line stage on which empty sample holders  161  not holding the samples  160  are transported, it is possible to set the distance of the space in the height direction, which is needed between the transport line stage on which the empty sample holders  161  are transported and the transport line stage on the upper stage side, to be within the height of the sample holder  161 . Consequently, the size of the sample transport apparatus  140  and the sample transport apparatus  150  for junction can be reduced in the height direction. 
     Furthermore, in this embodiment, the opening at the top of the housing  141  is covered with the transport line covers  142  and  152  in a detachable manner. Thus, transport lines can be easily accessed during maintenance, which results in increased efficiency of the maintenance operation. In addition, in the sample transport apparatus  140  in which the base substrate  143  is supported by the legs  145 , the height adjustment mechanism  204  is provided at the attachment portion between the base substrate  143  and the legs  145 . Thus, an operator is able to finely adjust the height of the transport lines in standing position. 
     OTHER EMBODIMENTS 
     It should be noted that the present invention is not limited to the structures of the aforementioned embodiments, and includes a variety of variations. For example, the aforementioned embodiments are only some of embodiments described in detail to clearly illustrate the present invention, and thus can be applied to other embodiments. In addition, the present invention need not include all of the structures described in the aforementioned embodiments. It is also possible to replace a part of a structure of the aforementioned embodiments with another structure. In addition, it is also possible to add, to a structure of the aforementioned embodiments, a structure of another embodiment. Further, it is also possible to remove a part of a structure of any of the aforementioned embodiments. 
     DESCRIPTION OF SYMBOLS 
     
         
           140  Sample transport apparatus 
           141  Housing 
           142  Transport line cover 
           143  Base substrate 
           144  Openable/closable door 
           145  Leg 
           150  Sample transport apparatus for junction 
           151  Housing 
           152  Transport line cover 
           153  Height adjustment leg 
           160  Sample 
           161  Sample holder 
           201  Upper-stage shelf board 
           202  Lower-stage shelf board 
           203  Post 
           204  Height adjustment mechanism 
           205  Power line for the belt driving motor 
           206  Power line for the stopper driving motor 
           207 ,  208 ,  209  Signal line 
           210  Power supply portion 
           211  Post member 
           212  Transport line mounting plate 
           213  Fixture 
           220  Belt driving motor 
           221  Stopper driving motor 
           222  Guide frame 
           223  Transport belt 
           224  Guide pin 
           225  Right-left connecting plates 
           226  Belt drive axis 
           230  Sub-transport line 
           231 ,  232  Stop plates 
           233  Direction changing arm 
           234  Direction changing arm driving motor