Patent Publication Number: US-2023158496-A1

Title: Fluid laying device, fluid laying method, fluid laying system, composite device, and fluid passage device

Description:
FIELD 
     The subject matter relates to a fluid laying device, a fluid laying method, a fluid laying system, a composite device, and a fluid passage device. 
     BACKGROUND 
     Fluid laying technology on a solid surface allows an even spread of fluid on a solid carrier. Such a technology is commonly used on non-enclosed carriers and includes spraying, atomization deposition, and coating. The uniformity of a fluid layer laid down by the above fluid laying technology mainly depends on the performance working mode of an external spraying device, and the flow factor or viscosity of the internal fluid is basically not an important factor. However, for the fluid laying technology to work efficiently in closed carriers, especially in carriers which include a channel with a fluid inlet and a fluid outlet, an inside channel may not be reached by fluid under external effects. In such circumstances, the fluid flow factors become important during fluid laying. 
     With the development of microfluidic technology in recent years, the research on fluid laying technology in carriers having channels has gradually increased. Pressure-driven is widely used in fluid laying because of its high controllability and ease of use. At present, a carrier widely available may have a channel structure with a large aspect ratio (a ratio of long side to short side), which has a low requirement for uniformity of fluid laying. A carrier with large aspect ratio generally requires a large movement space in a certain direction for a signal acquisition device to acquire signals indicate a large directional movement, which is not conducive to centralization or miniaturization of the signal acquisition device. In contrast, in this respect, a carrier with a small aspect ratio (such as square), has some advantage. However, an effective fluid laying method, device, and system are still absent in relation to a carrier with large surface area and small aspect ratio. 
     In addition, high-throughput sequencing is required in the commercial sequencing field, the advantages of the carrier with large surface area in realizing high-throughput sequencing tasks are clear. Designing and developing fluid laying or fluid passing methods suitable for a carrier with large surface area, especially developing fluid laying methods with controllable uniformity, is critical to the improvement of the throughput, performance, and quality of sequencing and the reduction of sequencing costs. Therefore, the demand for effective fluid laying technology for the carrier with large surface area is particularly urgent. 
     SUMMARY 
     In order to solve some or all of the above problems and other potential problems in the related art, a fluid laying device, a fluid laying method, a fluid laying system, a composite device, and a fluid passage device are needed. 
     In a first aspect, a fluid laying device for laying fluid on a flow cell carrier is provided. The fluid laying device includes a manifold block. The manifold block defines a first channel, the manifold block includes a first fluid inlet communicating with the first channel, a first fluid outlet, and a plurality of carrier interfaces. Each of the plurality of carrier interfaces defines a first hole, the first hole of each of the plurality of carrier interfaces is configured to connect one of a channel inlet and at least one channel outlet of the flow cell carrier. An inlet valve device, a bypass valve device, and a plurality of outlet valve devices are provided on the manifold block. The inlet valve device and the plurality of outlet valve device correspond to the plurality of carrier interfaces one-to-one, and are disposed on fluid paths from the corresponding carrier interfaces to the first channel for opening or closing the fluid paths. The first channel includes a first section and a second section, the bypass valve device is between the first section and the second section to control connection or disconnection between the first section and the second section, the inlet valve device is connected to the first section, and the plurality of outlet valve devices is connected to the second section. 
     Furthermore, the fluid laying device further includes a support table and a carrier mounting table, the carrier mounting table and the manifold block are disposed on the support table, and the carrier mounting table is configured to mount the flow cell carrier. 
     Furthermore, the carrier mounting table is configured to adsorb the flow cell carrier by vacuum adsorption or low-pressure adsorption, and or the manifold block surrounds the carrier mounting table. 
     Furthermore, the plurality of carrier interfaces disconnecting from the channel inlet and the at least one channel outlet of the flow cell carrier allows a fluid in the first channel to pass through the first hole of the corresponding carrier interface and enter the second hole of the corresponding carrier interface, and to finally flow out how the second fluid outlet through the second channel. 
     Furthermore, the manifold block further defines a second channel, the manifold block further includes a second fluid outlet communicating with the second channel, each of the plurality of carrier interfaces defines a second hole, and the second hole of each of the plurality of carrier interfaces is configured to communicate with the second channel. 
     Furthermore, the manifold block further defines a second fluid inlet communicating with the second channel, each of the plurality of carrier interfaces includes at least two second holes, the second channel is divided into a plurality of sections by the plurality of carrier interfaces, adjacent two of the plurality of sections communicate with each other through the second holes of the corresponding carrier interface, thereby allowing the fluid from the second fluid inlet to flow out from the second fluid outlet after passing through the plurality of carrier interfaces in sequence. 
     Furthermore, the manifold block further defines a second channel and a third channel, the manifold block further includes a second fluid inlet communicating with the second channel and a second fluid outlet communicating with the third channel, each of the plurality of carrier interfaces has at least two second holes, two of the at least two second holes communicate with the second channel and the third channel, thereby allowing a from the second fluid inlet to flow out from the second fluid outlet after passing through the plurality of carrier interfaces in sequence. 
     Furthermore, a sealing ring is arranged in each of the plurality of carrier interfaces, and each sealing ring defines a first bole communicating the first hole of the corresponding carrier interface. 
     Furthermore, each sealing ring further defines a second hole communicating with the second hole of the corresponding carrier interface, the second hole of the sealing ring allows the fluid from the first hole of the sealing ring to enter the second hole of the corresponding carrier interface. 
     Furthermore, each sealing ring includes a central portion and a ring body sleeved on the central portion, the ring body abuts against a wall of the corresponding carrier interface, the first hole of the sealing ring is defined on the central portion, and the second hole is defined on the ring body and communicates an upper side and a lower side of the ring body with each other. 
     Furthermore, each sealing ring includes a central portion, a ring body, and a connecting portion connecting the ring body and the central portion, the ring body abuts against a wall of the corresponding carrier interface, the first hole of the sealing one its defined on the central portion, and the second hole is defined on the connecting portion and communicates an upper side and a lower side of the connecting portion with each other. 
     Furthermore, the fluid laying device further includes the flow cell carrier, the flow carrier includes a base and a cover, a channel is formed between the base and the cover, and a portion of the manifold block constitutes the cover. 
     Furthermore, the portion of the manifold block constituting the cover defines the channel inlet and the at least one channel outlet, and the channel inlet and the at least one channel outlet communicate with the channel. 
     Furthermore, at least one groove for rectification of fluid is defined inn a site of the manifold block facing the base, the at least one groove communicates with the channel inlet and at least one of the channel outlet, and/or the groove communicates with a portion or all of the at least one channel outlet. 
     Furthermore, the portion of the manifold block constituting the cover defines one channel inlet and three channel outlets, any three of the fluid inlet and the fluid outlets are not on a same straight line. 
     Furthermore, the flow cell carrier is square, and the channel inlet and the channel outlets are distributed at four corners of the flow cell carrier. 
     Furthermore, the at least one groove for rectification of fluid includes two grooves, one of the two grooves communicates with the channel inlet and one of the channel outlets adjacent to the channel inlet, and the other of the two grooves communicates with another of the channel outlets adjacent to the channel inlet and a remaining channel outlet disposed diagonally opposite the channel inlet; or, the at least one groove for rectification of fluid is L-shaped and communicates with the three channel outlets. 
     Furthermore, the manifold block includes a plurality of sub-blocks, and each of the plurality of sub-block communicates with the corresponding channel through a pipeline. 
     Furthermore, the fluid laying device is configured to lay a nucleic acid sample or a reagent in the flow cell carrier. 
     In a second aspect, a fluid laying method is provided that configured to control the above fluid laying device to introduce a fluid into a channel in a flow cell carrier. The method including:
         controlling a power device to start, thereby allowing the power device to push the fluid into the fluid inlet of the fluid laying device;   controlling the bypass valve device to open, thereby allowing the fluid to flow from the fluid inlet to the fluid outlet;   controlling, the bypass valve device to close; and   controlling at least one of the inlet valve device and the plurality of outlet valve device to open, thereby allowing the fluid to enter and flow through the channel in the flow cell carrier.       

     Furthermore, a different one of the plurality of outlet valve devices is controlled to open or the plurality of outlet valve devices is controlled to open in sequence, thereby controlling a direction of the fluid in the flow cell carrier, so that the fluid lays at all positions of the channel in sequence. 
     Furthermore, a corresponding one of the plurality of outlet valve devices is controlled to open or the plurality of outlet valve devices is controlled to open in a specific order, according to distribution and extension direction of grooves for rectification of fluid in the flow cell carrier. 
     Furthermore, the at least one channel outlet includes three channel outlets, in two grooves for rectification of fluid in the flow cell carrier, a first groove communicates with the channel inlet and one of the channel outlets adjacent to the channel inlet, a second groove communicates with another of the channel outlets adjacent to the channel inlet and a remaining channel disposed diagonally opposite to the channel inlet, the specific order of controlling the plurality of outlet valve device to open includes: first controlling the outlet valve device corresponding to the channel outlet communicating with the first groove to open; then controlling the outlet valve device corresponding to the channel outlet disposed diagonally opposite to the channel inlet to open; finally controlling the outlet valve device corresponding to the channel outlet communicating with the second groove to open. 
     Furthermore, when the L-shaped groove in the flow cell carrier communicates with the three channel outlets, one of the plurality of outlet valve devices controlled to be open is the outlet valve device corresponding to the channel outlet at an apex position of the L-shaped groove. 
     Furthermore, the fluid laying method is configured to spread a nucleic acid sample or a reagent in the flow cell carrier. 
     Furthermore, the fluid laying method uses a positive pressure to push the fluid to realize fluid laying, and uses a negative pressure to collect a waste fluid. 
     In a third aspect, a fluid laying system is provided, which includes:
         the above fluid laying device;   a first power device configured to drive a fluid from a fluid source to enter and flow in the fluid laying device;   a valve device disposed between the power device and the fluid laying device, and configured to open or close a fluid path between the power device and the fluid laying device; and   a control device configured to control the power device, the valve device, and the inlet valve device and the plurality of outlet valve devices in the fluid laying device.       

     Furthermore, the fluid laying system further includes a second power device. The second power device is arranged downstream of the fluid laying device, and is configured to provide power for outflow of the waste fluid in the fluid laying device. 
     In a third aspect, a composite device is provided, which includes:
         the above fluid laying device; and   an auxiliary cleaning tool, the auxiliary cleaning tool including a plurality of cleaning structures, each of the plurality of cleaning structures configured to align with and install on one carrier interface of the fluid laying device, and guide the fluid in the first hole of the carrier interface into the second hole of the carrier interface.       

     Furthermore, the auxiliary cleaning tool further includes a body, the plurality of cleaning structures is provided on the body, when the body is installed on the fluid laying device, the plurality of cleaning structures corresponds to the plurality of carrier interfaces. 
     Furthermore, the cleaning structure is cap-shaped, and includes a top portion and a flange portion extending from an edge of the top portion toward the fluid laying device, a guiding structure is provided on an inner side of the top portion for guiding the fluid flowing out of the first hole of the carrier interface into the second hole of the carrier interface; or, a guiding groove is defined on an inner side of the top portion for guiding the fluid flowing out of the first hole of the carrier interface into the second hole of the carrier interface; or, a guiding groove being I-shaped, cross-shaped, or resembling the Union Jack flag is defined on an inner side of the top portion for guiding the fluid flowing out of the first hole of the carrier interlace into the second hole of the carrier interface. 
     Furthermore, the cleaning device is fixed to the body by adhesion or engagement. 
     A fluid passage device is also provided, which includes a manifold block. The manifold block defines at least one channel, the manifold block includes a fluid inlet communicating with the channel, a fluid outlet, and a plurality of carrier interfaces. The plurality of carrier interfaces configured to communicate a channel in the flow cell carrier when the flow cell carrier is installed on the fluid passage device. Each of the plurality of carrier interfaces has a first hole and a second hole, the second hole in each of the plurality of carrier interfaces is connected to the channel of the manifold block through a fluid path, the first hole in each of the plurality of carrier interfaces is connected to the channel of the manifold block through another fluid path, the first hole is configured to communicate with the channel in the flow cell carrier when the flow cell carrier is mounted on the fluid passage device. 
     The fluid entering the channel of the manifold block from the fluid inlet enters and exits the flow cell carrier through the first hole of each of the plurality of carrier interfaces, and then flows out through the fluid outlet; or, the fluid entering the channel of the manifold block from the fluid inlet enters the plurality of carrier interfaces through the first holes of the plurality of carrier interfaces, then enters the channel of the manifold block through the second holes of the plurality of carrier interfaces, and flows out from the fluid outlet; or, the fluid entering the channel of the manifold block from the fluid inlet enters and exits the plurality of carrier interfaces through the second holes, and then flows out through the fluid outlet. 
     Furthermore, a sealing ring is provided in each of the plurality of carrier interfaces, the sealing ring defines a first hole and a second hole, the first hole of the sealing ring communicates with the first hole of the corresponding carrier interface, and is used to communicate with the channel in the carrier of the flow cell, the second hole of the sealing ring allows the fluid from the first hole of the sealing ring to enter the second hole of the corresponding carrier interface. 
     Furthermore, the sealing ring includes a central portion and a ring body sleeved on the central portion, the ring body abuts against a wall of the corresponding carrier interface, the first hole of the sealing ring is defined on the central portion, the second hole is defined on the ring body and communicates an upper side and a lower side of the ring body with each other. 
     Furthermore, the sealing ring includes a central portion, a ring body, and a connecting portion connecting the ring body and the central portion, the ring, body abuts a wall of the corresponding carrier interface, the first hole of the sealing ring is defined on the central portion, the second hole is defined on the connecting portion and communicates an upper side and a lower side of the connecting portion with each other. 
     Furthermore, the channel of the manifold block includes a first channel communicating with the fluid inlet and a second channel communicating with the fluid outlet, a first hole of the carrier interface communicates with the first channel, and a second hole of the carrier interface communicates with the second channel. 
     Furthermore, the fluid outlet includes a first fluid outlet and a second fluid outlet, the channel of the manifold block includes a first channel communicating with the fluid inlet and the first fluid outlet and a second channel communicating with the second fluid outlet, the first hole of the carrier interface communicates with the first channel, the second hole of the carrier interface communicates with the second channel. 
     Furthermore, the fluid inlet includes a first fluid inlet and a second fluid inlet, the fluid outlet includes a first fluid outlet and a second fluid outlet, the channel of the manifold block includes a first channel communicating the first fluid inlet and the first fluid outlet, and a second channel communicating the second fluid inlet and the second fluid outlet, the first hole of the carrier interface communicates with the first channel, the second hole of the carrier interface communicates with the second channel. 
     Furthermore, the fluid inlet includes a first fluid inlet and a second fluid inlet, the fluid outlet includes a first fluid outlet and a second fluid outlet, the channel of the manifold block includes a first channel communicating the first fluid inlet and the first fluid outlet, a second channel communicating the second fluid inlet, and a third channel communicating the second fluid outlet, the first hole of the carrier interface communicates with the first channel, each of the plurality of carrier interface includes a plurality of second holes, at least one of the plurality of second holes of the carrier interface communicates with the second channel, at least another of the plurality of second holes communicates with the third channel. 
     Furthermore, different sections of at least one of the channel of the manifold block communicate with each other via the second hole of the carrier interface. 
     Furthermore, one of the channel of the manifold block includes at least two sections, each of the plurality of carrier interface includes a plurality of second holes, at least one of the plurality of second holes of the carrier interface communicates with one of the sections, and at least another of the plurality of second holes of the carrier interface communicates with another of the sections. 
     Furthermore, the manifold block includes a plurality of sub-blocks, and each of the plurality of sub-blocks communicates with the corresponding channel through a pipeline. 
     The fluid laying device, fluid laying method, and fluid laying system provided in the present disclosure uses a positive pressure for laying of fluid to significantly improve the fluid laying speed and reduce the possibility of bubbles on the flow cell carrier. They can be applied to the fluid laying of flow cell carriers with large size and small aspect ratio, and can significantly improve the efficiency of replacement among reagents that enter the flow cell carriers in sequence and the uniformity of a fluid layer. The cleaning device and method provided increase the maintainability and reliability of the fluid laying device, significantly improve the service life of the device, and reduce the failure rate of the device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Implementations of the present technology will now be described by way of embodiment, with reference to the attached figures. Obviously, the drawings are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. 
         FIG.  1 A  is a diagrammatic view of a flow cell carrier according to a first embodiment of the present disclosure. 
         FIG.  1 B  is a diagrammatic view of a flow cell carrier according to a second embodiment of the present disclosure. 
         FIG.  2    is a diagrammatic view of a fluid laying device according to a first embodiment of the present disclosure. 
         FIG.  3    is an exploded view of the fluid laying device of  FIG.  2   . 
         FIG.  4    is a diagrammatic view showing distributions of channels in a manifold block of the fluid laying device of  FIG.  2   . 
         FIG.  5    is a diagrammatic view showing flow directions of fluid in the manifold block of  FIG.  4   . 
         FIG.  6    is a diagrammatic view showing flow directions of fluid in the manifold block and the flow cell carrier of  FIG.  4   . 
         FIGS.  7 A to  7 C  are diagrammatic views showing fluid laying processes in a flow cell carrier according to an embodiment of the present disclosure. 
         FIG.  8    is a perspective view of an auxiliary cleaning tool according to an embodiment of the present disclosure. 
         FIG.  9    is a perspective view of a cleaning device according to an embodiment of the present disclosure. 
         FIG.  10 A  is a perspective view of a sealing ring according to an embodiment of the present disclosure. 
         FIG.  10 B  is a partial cross-sectional view of the sealing ring of  FIG.  10 A . 
         FIG.  11    is a diagrammatic view showing distributions of channels in a manifold block of a fluid laying device according to a second embodiment of the present disclosure. 
         FIG.  12    is a diagrammatic view showing distributions of channels in a manifold block of a fluid laying device according to a third embodiment of the present disclosure. 
         FIG.  13    is a diagrammatic view of a fluid laying system according to a first embodiment of the present disclosure. 
         FIG.  14    is a diagrammatic view of a fluid laying system according to a second embodiment of the present disclosure. 
     
    
    
     Specific embodiments will further explain the present disclosure in combination with the above drawings. 
     Symbols of main components: 
     Flow cell carrier  1   a:    1   b,    72 , of  82 ; channel  11   a  or  11 ;
 
base  13   a  or  13   b:  cover  15   a  or  15   b;  
 
channel inlet  111   a  or  111   b;  channel outlet  113   a  or  113   b;  
 
groove  115   a    115   b,  fluid laying device  2 ,  5 ,  6 , or  71 ;
 
manifold block  21 ,  41 ,  51 , or  61 ; support table  22  or  42 ;
 
carrier mounting table  23  or  43 ; gas channel  231 ;
 
vacuum adapter  232  temperature control module  24 ;
 
temperature detector  25 ; first channel  211 ,  511 , or  611 ;
 
second channel  212 ,  512 , or  612   a;  fluid inlet  213  or  414 ;
 
first fluid outlets  214 ,  514 , or  614 ; second fluid outlet  216 ,  516 , or  616 ;
 
valve connection port  217 ,  517 , or  617 , valve device  218 ,  618 ,  751 ,  752 , or  85 ;
 
inlet valve device  218   a;  outlet valve device  218   b;  
 
bypass valve device  218   c;  carrier interface  219 ,  413 ,  518 , or  619 ;
 
sealing ring  26 ,  44 ,  52 , or  62 ; first hole  261 ,  2191 ,  441 ,  4131 ,  521 , or  621 ;
 
second hole  262 ,  2192 ,  442 ;  4132 , or  522 ; central portion  263  or  443 ;
 
ring body  264  or  444 ; auxiliary cleaning tool  31 ;
 
cleaning structure  311 ; main body  310 ;
 
positioning structure  312 ; mounting structure  313 ;
 
top portion  3111 ; flange portion  3113 ;
 
guiding structure  3115 ; cleaning device  4 ;
 
first section  411 ; second section  412 ;
 
connecting portion  445 ; fluid outlet  415 ;
 
joint  416 ; first fluid inlet  513  or  613 ;
 
second fluid inlet  515  or  615 ; third channel  612   b;  
 
fluid laying system  7  or  8 ; fluid source  73  or  83 ;
 
reagent fluid source  731 ; cleaning fluid source  733 ;
 
power device  741 ,  742 ,  743 ,  841 , or  842 ; waste fluid storage unit  76  or  86 ;
 
pneumatic unit  77  or  87 ; control device  78  or  88 ;
 
functional device  81 .
 
     DETAILED DESCRIPTION 
     Implementations of the disclosure will now be described, by way of embodiments only, with reference to the drawings. The described embodiments are only portions of the embodiments of the present disclosure, rather than all the embodiments. The disclosure is illustrative only, and changes may be made in the detail within the principles of the present disclosure. It will, therefore, be appreciated that the embodiments may be modified within the scope of the claims. 
     It should be noted that when a component is considered to be “disposed on”another component, the component can be arranged directly on another component, or there may be intermediate components therebetween. The term “and/or”as used herein includes all or any combination of one or more related listed items. 
     Referring to  FIG.  1 A , a flow cell carrier with a small aspect ratio is shown according to a first embodiment of the present disclosure. In the embodiment, the flow cell carrier  1   a  is square in shape, and has a square channel  11   a  inside. The flow cell carrier  1   a  has a base  13   a  on the lower side and a cover  15   a  on the upper side. The cover  15   a  covers the base  13   a,  and the channel  11   a  is formed between the cover  15   a  and the base  13   a.  Openings are defined on four corners of the base  13   a.  One of the openings is a channel inlet  111   a,  the other three of the openings are channel outlets  113   a.  Sealing rings (not shown) are provided outside the channel inlet  111   a  and the channel outlets  113   a.  A groove  115   a  is defined between the channel inlet  111   a  and one channel outlet  113   a  adjacent thereto (hereinafter referred to as a first channel outlet  113   a ). Another groove  115   a  is defined between the other two channel outlets  113   a.  The two grooves  115   a  are defined on a side of the base  13   a  facing the channel  11   a.  The two grooves  115   a  are used for rectification of fluids. One of the channel outlets  113   a  is disposed diagonally opposite the channel inlet  111   a  (hereinafter referred to as a second channel outlet  113   a ). The other channel outlet  113   a  (hereinafter referred to as a third channel outlet  113   a ) is adjacent to the channel inlet  111   a.  The first channel outlet  113   a  and the third channel outlet  113   a  are disposed at two sides of a line connecting the channel inlet  11   a  to the second channel outlet  113   a.    
     Referring to  FIG.  1 B , a flow cell carrier with a small aspect ratio is shown according to a second embodiment of the present disclosure. In the embodiment, the flow cell carrier  1   b  is also square, and has a square channel  11   b  inside. The flow cell carrier  1   b  has a base  13   b  on the lower side and a cover  15   b  on the upper side. The cover  15   b  covers the base  13   b,  and the channel  11   b  is formed between the cover  15   b  and the base  13   b.  Openings are defined at four corners of the base  13   b.  One of the openings is a channel inlet  111   b,  and the other three of the openings are channel outlets  113   b.  Sealing rings (not shown) are provided outside the channel inlet  111   b  and the channel outlet  113   b.  An L-shaped groove  115   b  for fluid rectification is defined by the three channel outlets  113   b.  The L-shaped groove  115   b  extends from one of the channel outlets  113   b  adjacent to the channel inlet  111   b  (hereinafter referred to as a first channel outlet  113   b ) to the channel outlet  113   b  disposed diagonally opposite the channel inlet  111   b  (hereinafter referred to as a second channel outlet  113   b ), and then extends from the second channel outlet  113   b  to the other channel outlet  113   b  adjacent to the channel inlet  111   b  (hereinafter referred to as a third channel outlet  113   b ). The second channel outlet  113   b  is disposed at an apex of the L-shaped groove  115   b.    
     The L-shaped groove  115   b  is formed on a surface of the base  13   b  facing the channel  11   b.  The first channel outlet  113   b  and the third channel outlet  113   b  are disposed at two sides of a connecting line connecting the channel inlet  111   b  to the second channel outlet  113   b.    
     Referring to  FIGS.  2  and  3   , a fluid laying device  2  is shown according to a first embodiment of the present disclosure. The fluid laying device  2  of the embodiment can be used to lay fluid on the flow cell carrier  1   a  shown in  FIG.  1 A  and the flow cell carrier  1   b  shown in  FIG.  1 B . The fluid laying device  2  includes a manifold block  21 , a support table  22 , and a carrier mounting table  23 . The carrier mounting table  23  is disposed at a center of the support table  22  for mounting the flow cell carrier. In the embodiment, the carrier mounting table  23  adsorbs the flow cell carrier onto the carrier mounting table  23  by vacuum adsorption. Outer surface of the base of the flow cell carrier functions as a mounting surface to be adsorbed on the carrier mounting table  23 . A gas channel  231  is defined on the carrier mounting table  23 , which is connected to an external vacuum source (not shown) through a vacuum adapter  232 . In the embodiment, a temperature control module  24  is disposed under the carrier mounting table  23 . The temperature control module  24  can be used when necessary to provide an appropriate temperature for fluid in the flow cell carrier mounted on the carrier mounting table  23 . A temperature detector  25  is provided at a side of the temperature control module  24 . The temperature detector  25  cooperates with the temperature control module  24  to facilitate a control device (not shown) to control the temperature of the fluid in the flow cell carrier. 
     The manifold block  21  is disposed on the support table  22  and surrounds the carrier mounting table  23 . In the embodiment, the manifold block  21  may be fixed to the support table  22  by mechanical fastening, such as by screw fastening or block clamping. Channels are defined in the manifold block  21 . Referring to  FIG.  4   , the channels include a first channel  211  and a second channel  212 . In addition, the manifold block  21  also defines a number of openings communicating with the interior channels. The openings include a fluid inlet  213 , a first fluid outlet  214 , a second fluid outlet  216 , and a number of valve connection ports  217 . The manifold block  21  is connected to a number of valve devices  211  through the valve connection ports  217 . A control device can control the valve devices  218  to open or close a certain channel, thereby guiding the flow direction of the fluid. In the embodiment, the valve devices  218  include an inlet valve device  218   a  corresponding to the flow cell carrier inlet, an outlet valve device  218   b  corresponding to each channel outlet of the flow cell carrier, and a bypass valve device  218   c  between the inlet valve device  218   a  and one outlet valve device  218   b.  In the embodiment, the valve devices  218  may be two-way valves for example. The present disclosure does not limit the type of the valve device  218 , and the valve device  218  may be other type of valve device, as long as the method is allowed to function. 
     Each outlet valve device  218   b  corresponds to a channel outlet of the flow cell carrier. The outlet valve devices  218   b  may correspond to the channel outlets of the flow cell carrier one-to-one. Taking the flow cell carrier  1   a  shown in  FIG.  1 A  for fluid laying for example, there are three outlet valve devices  218   b,  which correspond to the three channel outlets  113   a  of the flow cell carrier  1 . Taking the flow cell carrier  1   a  shown in  FIG.  1 B  for fluid laying for example, there are three outlet valve devices  218   b,  which correspond to the three channel outlets  113   b  of the flow cell carrier  1   b.    
     Carrier interfaces  219  are also provided on the manifold block  21 . The carrier interfaces  219  correspond to the channel inlet and the channel outlets of the flow cell carrier one-to-one. Taking the flow cell carrier  1   a  shown in  FIG.  1 A  for fluid laying for example, four carrier interfaces  219  are provided on the manifold block  21 . One of the carrier interfaces  219  corresponds to the channel inlet  111   a  of the flow cell carrier  1   a,  and the other three carrier interfaces  219  correspond to the channel outlets  113   a  of the flow cell carrier  1   a  one-to-one. Each carrier interface  219  defines a first hole  2191  and a second hole  2192 . The first hole  2191  communicates with the inlet valve device  218   a  or with the outlet valve device  218   b.  The second hole  2192  communicates with the second channel  212 . A sealing ring  26  is installed in each carrier interface  219 . The sealing ring  26  defines a first hole  261  and a second hole  262 . The first hole  261  communicates with the first hole  2191  of the carrier interface  219 . The second hole  262  communicates with the second hole  2191  of the carrier interface  219 . After the flow cell carrier  1   a  is placed on the mounting table  23 , the openings of the flow cell carrier  1   a  are aligned with the sealing rings  26  one-to-one, and the first hole  261  of each sealing ring  26  communicates with the channel inlet  111   a  or with the channel outlet  113   a  of the flow cell carrier  1   a.  As such, the channel inlet  111   a  of the flow cell carrier  1   a  is connected to the first channel  211  through the first holes  2191  of the inlet earlier interface  219  and the inlet valve device  218 A. Also, the channel outlet  113   a  of the flow cell carrier  1   a  is connected to the first channel  211  through the second bole  2192  of the carrier interface  219  and the outlet valve device  218   b.  Therefore, the fluid in the first channel  211  can enter the flow cell carrier  1   a  through the inlet valve device  218   a,  the first boles  2191  and  261  and the channel inlet  111   a.  Also, the fluid in the flow cell carrier  1   a  can enter the first channel  211  through the channel outlet, the first holes  261  and  2191 , and the outlet valve device  218   b.  The second hole  262  of the sealing ring  26  communicates with the second channel  212  through the second hole  2192  of the carrier interface  219 . In the embodiment, the sealing ring  26  includes central portion  263  and a ring body  264  sleeved on the central portion  263 . The first hole  261  is defined on the central portion  263 . Edge of the ring body  264  abuts against a wall of the carrier interface  219  to seal the wall of the carrier interface  219 . The ring body  264  has a notch, which is the second hole  262 . The second hole  262  penetrates upper and lower sides of the ring body  264 . The upper side of the ring body  264  faces the exterior of the carrier interface  219 , and the lower side of the ring body  264  faces the interior of the carrier interface  219 . The second hole  262  guides path of cleaning fluid and rectifies and limits the flow of the cleaning fluid. Thus, residue on the sealing ring  26  can be removed. 
     Through the channels defined in the manifold block  21 , the inlet valve device  218   a  communicates with the first channel  211  and the first hole  261  of the corresponding sealing ring  26  installed at the channel inlet of the flow cell carrier. Through the channels defined in the manifold block  21 , each outlet valve device  218   b  communicates with the first channel  211  and the first hole  261  of the corresponding sealing ring  26  installed at the channel outlet of the flow cell carrier. In the embodiment, the bypass valve device  218   c  is disposed on the first channel  211 . Taking the bypass valve device  218   c  as a criterion, the first channel  211  includes a first section before the bypass valve device  218   c  and a second section after the bypass valve device  218   c.  The inlet valve device  218   a  is connected to the first section, and all the outlet valve devices  218   b  are connected to the second section. The bypass valve device  218   c  is connected to the two sections of the first channel  211  through the channels defined on the manifold block  21 , thereby controlling the first channel  211  to be open or closed. 
     In the embodiment, one end of the first channel  211  communicates with the fluid inlet  213 , the other end communicates with the first fluid outlet  214 , and the center portion communicates with the bypass valve device  218   c,  thereby allowing the bypass valve device  218   c  to open or close the first channel  211 . When the bypass valve device  218   c  is opened, the fluid flowing into the first channel  211  from the fluid inlet  213  can further flow out of the manifold block  21  through the first fluid outlet  214 . In the embodiment the fluid inlet  213  is a fluid inlet which can be used in common, through which reagents and the cleaning fluid to the manifold block  21  are supplied at different time periods. The first channel  211  is a common channel, though which the reagent and the cleaning fluid flow at different time periods. The second channel  212  is a channel for the cleaning fluid, which communicates with the second hole  2192  of the carrier interface  219  and the second fluid outlet  216 . As shown in  FIG.  5   , the fluid entering the first channel  211  from the fluid inlet  213  can enter the flow cell carrier through the inlet valve device  218   a,  exit the outlet valve device  218   b,  and then flow through the first channel  211  and exit the fluid laying device  2  from the first fluid outlet  214 . Thus, laying of fluid in the flow cell carrier is realized. In the present disclosure, a circuit for supplying fluid into and out of the flow cell carrier to achieve fluid laying in the flow cell carrier is called as a “fluid laying circuit”. In the embodiment, the first channel  211  constitutes the fluid laying circuit. The fluid entering the first channel  211  from the fluid inlet  213  may pass through the bypass valve device  218   c,  then pass through the other section of the first channel  211 , and finally be discharged out of the fluid laying device  2  from the first fluid outlet  214 . Thus, excess fluid is discharged. The fluid entering the first channel  211  from the fluid inlet  213  may also enter the first hole  261  of the sealing ring  26  through the inlet valve device  218   a,  then enter the second channel  212  through the second hole  262 , and be discharged out of the fluid laying device  2  from the second fluid outlet  216 . Thus, some of channels and some the sealing rings  26  in the manifold block  21  are cleaned. The fluid entering the first channel  211  from the fluid inlet  213  may also enter the first hole  261  of the willing ring  26  through any of the outlet valve devices  218   b,  then enter the second channel  212  through the second hole  262 , and then be discharged out of the fluid laying device  2  from the second fluid outlet  216 . In the present disclosure, a circuit for allowing fluid to flow through to clean relevant pipelines and components of the manifold block and/or the flow cell carrier is called as a “cleaning circuit”. In the embodiment, the first channel  211  and the second channel  212  constitute the cleaning circuit. Flow direction of the fluids described above is achieved by controlling the inlet valve device  218   a,  the outlet valve devices  218   b,  and the bypass valve device  218   c.    
     In actual use, the flow cell carrier is mounted on the mounting table  23 . Each of the channel inlet and channel outlets of the flow cell carrier are pressed against the sealing ring  26  at a corresponding position. The first hole  261  of the sealing ring  26  is aligned with the channel inlet or channel outlet of the flow cell carrier. The fluid inlet  213  of the manifold block  21  is connected to an upstream pump (such as a syringe pump not shown) through a valve device (not shown), and the second fluid outlet  216  is connected to a downstream pump (not shown) through another valve device (not shown). The upstream pump, the downstream pump, the inlet valve device  218   a,  the outlet valve devices  218   b,  and the bypass valve device are all connected to the control device, and are started or opened by the control device. 
     Taking the flow cell carrier  1   a  shown in  FIG.  1 A  for fluid laying and cleaning for example, a fluid laying method and a cleaning method for subsequent cleaning of the fluid laying device  2  are as follows. 
     Fluid laying process: 
     As shown in  FIGS.  6  and  7 A to  7 C , after the flow cell carrier  1   a  is mounted on the mounting table  23 . the inlet valve device  218   a  corresponds to the channel inlet  111   a  of the flow cell carrier  1   a.  The first outlet valve device  218   b  corresponds to the first channel outlet  113   a,  the second outlet valve device  218   b  corresponds to the second channel outlet  113   a,  and the third outlet valve device  218   b  corresponds to the third channel outlet  113   a.  During the fluid laying process, the upstream pump is first started, and the reagent functioning as the fluid is pushed to the fluid inlet  213  by the upstream pump. Next, the inlet valve device  218   a  and the bypass valve device  218   c  are controlled to open. The reagent flows through the first channel  211 , so that the reagent fully infills between the fluid inlet  213  of the manifold block  21  and the channel inlet  111   a  of the flow cell carrier  1   a.  Then, the bypass valve device  218   c  is controlled to close and the first outlet valve device  218   b  is opened, and the upstream pump is controlled to continue pumping. Thus, the fluid enters the flow cell carrier  1   a  through the inlet valve device  215   a  and the channel inlet  111   a,  and further flows along the groove  115   a  toward the first channel outlet  113   a.  During such process, a portion of the fluid overflows from the groove  115   a  and forms a frontal blunt surface in the channel  11   a.  The first outlet valve device  218   b  is controlled to close and the second outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping. The fluid enters the channel  11   a  through the inlet valve device  218   a  and the channel inlet  111   a,  and further flows from the channel inlet  111   a  to the second channel outlet  113   a.  The second outlet valve device  218   b  is controlled to close and the third outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping. The fluid enters the channel  11   a  through the is valve device  218   a  and the channel inlet  111   a,  and floss from the channel inlet  111   a  to the third channel outlet  113   a.  In this way, laying of fluid uniformly is realized on the entire channel  11   a  of the flow cell carrier  1   a.  The residual fluid after the fluid laying process flows out from the first fluid outlet  214 . In the above steps, for a fluid with low viscosity, the upstream pump can perform a single step of fluid pumping. For the fluid with higher viscosity, the upstream pump can perform fluid pumping in multiple steps. 
     Cleaning process: 
     In order to avoid contamination during next laying of fluid, or influence of internal solutes on the components of the fluid laying device, the fluid residue at each channel/pipeline and the sealing ring  26  of manifold block  21  must be removed. One or more cleaning processes are carried out after the one or more fluid laying processes. 
     The flow cell carrier is removed before cleaning. In the cleaning process, the upstream pump is first started, and the cleaning fluid functioning as a fluid is pushed to the fluid inlet  213  by the upstream pump. Next, the bypass valve device  218   c  is controlled to open, and the cleaning fluid passes through the first channel  211  to the first fluid outlet  214 , so that the downstream pipe between the first channel  211  and the manifold block  21  is filled with the cleaning fluid. The downstream pump is started to keep the cleaning circuit under a negative pressure, so that the cleaning fluid can be discharged. The third outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the third outlet valve device  218   b.  The cleaning fluid drops into the second hole  262  of the sealing ring  26 , and then passes through the second channel  212  and the second fluid outlet  216  and is collected by the downstream pump. The second outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the second outlet valve device  218   b,  then dropping into the second hole  252  of the sealing ring  26 , and then passing through the second channel  212  and the second fluid outlet  216  to be collected by the downstream pump. The first outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the first outlet valve device  218   b,  drops into the second hole  262  of the sealing ring  26 , and then passes through the second channel  212  and the second fluid outlet  216 , being collected by the downstream pump. The inlet valve device  218   a  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  of the corresponding inlet valve device  218 A, falls into the second bole  262  of the sealing ring  26 , and is collected by the downstream pump through the second channel  212  and the second fluid outlet  216 . In the above cleaning method, the pressure source located upstream of the fluid laying device  2  (the upstream pump) drives the cleaning fluid with positive pressure to pass through and reach the designated pipeline and sealing ring. Then, a pressure source located downstream of the cleaning circuit (the downstream pump) collects and discharges the cleaning fluid. The cleaning method can also be repeated many times to achieve constant cleanliness. 
     Another fluid laying method of the present disclosure and another cleaning method for cleaning the fluid laying device  2  after the fluid laying process is described by taking the fluid laying and cleaning processes applied to the flow cell carrier  1   b  of  FIG.  1 B  as an example. 
     Fluid laying process: 
     After the flow cell carrier  1   b  is mounted on the mounting table  23 , the inlet valve device  218   a  corresponds to the channel inlet  111   b  of the flow cell carrier  1   b.  The first outlet valve device  218   b  corresponds to the first channel outlet  113   b,  the second outlet valve device  218   b  corresponds to the second channel outlet  113   b,  and the third outlet valve device  218   b  corresponds to the third channel outlet  113   b.  During the fluid laying process, the upstream pump is first started, and the reagent as the fluid is pushed to the fluid inlet  213  by the upstream pump. Next, the bypass valve device  218   c  is controlled to open, and the reagent flows through the first channel, so that the reagent fully infills in between the fluid inlet  213  of the manifold block  21  and the channel inlet  111   b  of the flow cell carrier  1   b.  Then, the bypass valve device  218   c  is closed and the second outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid. The reagent enters the flow cell carrier  1   b  through the inlet valve device  218   a  and the channel inlet  111   b.  The front edge of the reagent is fan-shaped. The reagent is finally guided to the second channel outlet  113   b  through the right angled L-shaped groove  115   b.  In this way, the laying of fluid is done uniformly on the entire channel  11   b  of the flow cell carrier  1   b.  The residual fluid after the thud laying process flows out from the first fluid outlet  214  through the second outlet valve device  218   b.  In the above steps, for the fluid with a loss viscosity, the upstream pump can perform a single step of fluid pumping. For the fluid with higher viscosity, the upstream pump can perform fluid pumping in multiple steps. 
     Cleaning process: 
     In the cleaning method currently described, an auxiliary cleaning tool is used to assist in the cleaning process. Referring to  FIG.  8   , a diagrammatic view of the auxiliary cleaning tool is shown according to a first embodiment of the present disclosure. In the embodiment, the end faces of the cleaning structures  311  of the auxiliary cleaning tool  31  press against the periphery of the inlet and outlet of the manifold block  21  for fluid to enter and exit the flow cell carrier. 
     The auxiliary cleaning tool  31  includes a main body  310 , the cleaning structures  311 , positioning structures  312 , and a mounting structure  313  disposed on the main body  310 . The mounting structure  313  is used to mount the main body  310  to the fluid laying device  2 . In the embodiment, the mounting structure  313  is a mounting surface corresponding to the carrier mounting table  23 . In the embodiment where vacuum adsorption is used by the carrier mounting table  23  to fix objects, the mounting surface may be one suitable for adsorption. The positioning structures  312  are used for positioning purposes when a robot grips and installs the auxiliary cleaning tool  31  on the fluid laying device  2 . In the embodiment, each positioning structure  312  has an indication for direction. The cleaning structures  311  correspond to the carrier interfaces  219  on the fluid laying device  2 . In the embodiment, each cleaning structure  311  is generally cap-shaped, and includes a top portion  3111  and a flange portion  3113 . The flange portion  3113  extends from the edge of the top portion  3111  toward the fluid laying device  2 . The end face of the flange portion  3113  abuts against the periphery of the inlet and outlet of the manifold block  21  for fluid to enter exit the flow cell carrier. In the embodiment, each cleaning structure  311  is fixed to the main body  310  by adhesion or by mechanical clamping, and the main body  310  defines a hole or a recess for receiving the cleaning structures  311 . The entire cleaning structure  311  or only the flange portion  3113  is made of an elastic material or a deformable material which may be rubber, silica del, foam rubber, etc. A guiding structure  3115  is provided on the inner side of the top portion  3111  of each cleaning structure  311 . The guiding structure  3114  is used to guide fluid from the middle area of the cleaning structure  311  to the edge area of the cleaning structure  311 . When the auxiliary cleaning tool  31  is mounted to the fluid laying device  2  to assist the cleaning of the fluid laying device  2 , the cleaning structures  311  correspondingly cover on the sealing rings  26  of the fluid laying device  2 . The cleaning fluid from the first hole  261  of the sealing ring  26  is guided to the second hole  262  through the guiding structure  3115 , enters the second channel  212 , and then is collected and discharged by the downstream pump. In one embodiment, the guiding structure  3115  is a guiding groove. The guiding groove can be I-shaped, cross-shaped, or resembling the Union Jack flag. 
     The cleaning process using the auxiliary cleaning tool  31  to assist in cleaning is as follows. 
     First, the auxiliary cleaning tool  31  is mounted on the fluid laying device  2 , causing the cleaning structures  311  of the auxiliary cleaning tool  31  to cover the sealing rings  26  of the fluid laying device  2  one-to-one. The upstream pump is started, and the cleaning fluid as the fluid is pushed to the fluid inlet  213  by the upstream pump. The bypass valve device  218   c  is controlled to open, and the cleaning fluid flows through the first channel  211  to the first fluid outlet  214 , so that the downstream pipe between the first channel  211  and the manifold block  21  is filled with the cleaning fluid. The down ream pump is started to keep the cleaning circuit under a negative pressure, so that the cleaning fluid can be discharged. The third outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid. Thus, the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the third outlet valve device  218   b,  is guided by the corresponding cleaning structure  311 , flows into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be collected by the downstream pump. The second outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid. Thus, the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the second outlet valve device  218   b,  is guided by the corresponding cleaning structure  311  into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be collected by the downstream pump. The first outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid. Thus, the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the first outlet valve device  218   b,  is guided by the corresponding cleaning structure  311  into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be collected by the downstream pump. The inlet valve device  218   a  is controlled to open, and the upstream pump is controlled to continue pumping fluid. Thus, the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the inlet valve device  218   a,  is guided by the corresponding cleaning structure  311  into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be collected by the downstream pump. 
     A second embodiment of an auxiliary cleaning tool is also provided according to the present disclosure. The auxiliary cleaning tool of the second embodiment is generally similar to the auxiliary cleaning tool  31  of the first embodiment. The main difference is that after the auxiliary cleaning tool of the second embodiment is installed in the the laying device  2 , gaps (not shown) exist between the cleaning structures of the auxiliary cleaning tool and the periphery of the inlet and outlet of the manifold block  21  for fluid to enter and exit the flow cell carrier. The gaps are used to balance the pipeline pressure between the cleaning circuit and the fluid circuit in the flow cell carrier. In the embodiment, each cleaning structure and the carrier interface  219  on the fluid laying device  2  may form a male-female connection structure. A one-way valve or a two-way solenoid valve (not shown) is provided downstream of the fluid laying circuit, that is, downstream of the first fluid outlet  214 , which reduces or prevents the backflow of fluid in the downstream pipeline of the fluid laying device  2 . 
     In the embodiment, the cleaning process assisted by the auxiliary cleaning tool is as follows. 
     First, the downstream pump of the cleaning circuit is started to keep the cleaning circuit, a negative pressure state, so that the cleaning fluid can be discharged. The auxiliary cleaning tool is installed on the fluid laying device  2 , and the cleaning structures of the auxiliary cleaning tool correspondingly cover the sealing rings  26  of the fluid laying device  2  one-to-one. The upstream pump is started, and the cleaning fluid as the fluid is pushed to the fluid inlet  213  by the upstream pump. The bypass valve device  218   c  is controlled to open, and the one-way valve or two-way solenoid valve downstream of the fluid laying circuit is also controlled to open. The cleaning fluid flows through the first channel  211  and the first fluid outlet  214  toward the downstream pipe, so that the first channel and the downstream pipe of the manifold block  21  are filled with the cleaning fluid. The one-way valve or two-way solenoid valve downstream of the fluid laying circuit is controlled to close the downstream pipeline, thereby reducing or preventing the backflow of fluid. The third outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the third outlet valve device  218   b,  is guided by the corresponding cleaning structure into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be collected by the downstream pump. The second outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  corresponding to the second outlet valve device  218   b,  is guided by the corresponding cleaning structure into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be then collected by the downstream pump. The first outlet valve device  218   b  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring corresponding to the first outlet valve device  218   b,  is guided by the corresponding cleaning structure  311  into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be then collected by the downstream pump. The inlet valve device  218   a  is controlled to open, and the upstream pump is controlled to continue pumping fluid, so that the cleaning fluid is pushed out from the first hole  261  of the sealing ring  26  of the corresponding inlet valve device  218 A, is guided by the corresponding cleaning structure into the second hole  262  of the sealing ring  26 , and further passes through the second channel  212  and the second fluid outlet  216  to be then collected by the downstream pump. 
     Referring to  FIG.  9   , a cleaning device for cleaning the channel inlet and channel outlet of a flow cell carrier is shown according to an embodiment of the present disclosure. The cleaning device  4  can be used together with the fluid laying device  2  to clean the areas around the channel inlet and the channel outlet of the flow cell carrier at a fixed frequency of cleaning, thereby maintaining the cleanliness of the mounting surface of the flow cell carrier. The cleaning device  4  includes a manifold block  41  a support table  42 , and a carrier mounting table  43 . The carrier mounting table  42  is arranged in the middle of the support table  41  for mounting the flow cell carrier. In the embodiment, the carrier mounting table  43  adsorbs the flow cell carrier on the carrier mounting table  43  by vacuum adsorption. Outer surface of the base of the flow cell carrier functions as a mounting surface to be adsorbed on the carrier mounting table  43 . The manifold block  41  includes a plurality of sub-blocks  410  surrounding the carrier mounting table  43 . Each sub-block  410  corresponds to the channel inlet or the channel outlet of the flow cell carrier. For example, the cleaning device  4  can be used to clean the flow cell carrier  1   a  shown in  FIG.  1 A . The manifold block  41  includes four sub-blocks  410  corresponding to the flow cell carrier  1   a.  One of the sub-blocks  410  corresponds to the channel inlet  111   a  of the flow cell carrier  1   a.  The other three sub-blocks  410  correspond to the flow outlets  113   a  of the flow cell carrier  1   a.  Each sub-block  410  defines a channel having two sections, that is, a first section  411  and a second section  412 . Each sub-block  410  is further provided with a carrier interface  413  at a position facing the channel  111   a  or the channel outlet  113   a  of the flow cell carrier  1   a.  The carrier interface  413  is used for mounting a sealing ring  44 . Referring to  FIGS.  10 A and  10 B , the sealing ring  44  defines a first hole  441  and a second hole  442 . In the embodiment, the sealing ring  44  includes a central portion  443  as an inner ring and a ring body  444  as an outer ring. The outer side of the ring body  444  abuts against the wall of the carrier interface  413  to seal the wall of the carrier interface  413 . The ring body  444  is spaced apart from the central portion  443  and connected to the central portion  44  by a connecting portion  445 . The connecting portion  445  separates the space between the ring body  444  and the central portion  443  into upper and lower layers. The connection portion  445  defines a hole, which allows communication of the upper and lower layers of the space with each other. The first hole  441  is defined in the central portion  443 , and the hole of the connecting portion  443  is the second hole  442 . The second hole  442  guides path of cleaning fluid and rectifies and limits the flow of the cleaning fluid. Thus, residue on the sealing ring  44  can be removed. 
     The bottom of the carrier interface  413  defines two holes, that is, a first hole  4131  and a second hole  4132 . The first hole  4131  communicates with the first section  411  and the first hole  441  of the sealing ring  44 . The second hole  4132  communicates with the second section  412  and the second hole  442  of the sealing ring  44 . The first section  411  communicates with the fluid inlet  414  defined on the manifold block  41 , and the second section  412  communicates with the fluid outlet  415  defined on the sub-block  410 . A joint  416  is installed on each of the fluid inlet  414  and the fluid outlet  415 , and the upstream and downstream pipelines are connected to each other by the joint  416 . Specifically, in the embodiment, the fluid inlet  414  of one of the sub-blocks  410  serves as the fluid inlet of the manifold block  41  as a whole, which is connected to an upstream cleaning fluid source through a pipeline. The fluid outlet  415  of another sub-block  410  serves as the fluid outlet of the manifold block  41  as a whole, this is connected to the downstream pump of the cleaning platform  4  through a pipeline. The sub-blocks  410  are connected in series with each other. The fluid outlet  415  of the previous sub-block  410  is connected to the fluid inlet  414  of the next, sub-block  410 . The fluid entering from the fluid inlet  414  of the manifold block  41  passes through the sub-blocks  410  in sequence and flows out from the fluid outlet  415  of the manifold block  41 . When the fluid passes through the carrier interface  413  of each sub-block  410 , the fluid cleans the area around the channel inlet or channel outlet of the flow cell carrier. 
     The specific cleaning process is as follows: 
     After the fluid laying is completed or before the fluid laying is started, the flow cell carrier is transferred and installed to the cleaning device  4 . Each of the channel inlet and channel outlets of the flow cell carrier is aligned with the first hole  441  of the sealing ring  44  and the sealing ring  44  seals the flow cell carrier. The downstream pump is started. After the cleaning fluid as the fluid enters from the cleaning fluid source to the fluid inlet  414  of the cleaning device  4 , the cleaning fluid flows through the sub-blocks  410  in sequence and fills the cleaning circuit. Thus, the channel inlet and the channel outlets of the flow cell carrier are immersed and cleaned by the cleaning fluid. This cleaning process is applied for a period of time, for example, three to ten seconds, and then the downstream valve is closed to stop the cleaning process. 
     Referring to  FIG.  11   , a fluid laying device is shown according to a second embodiment of the present disclosure. The hardware structure of the fluid laying device  5  is basically the same as that of the fluid laying device  2 . The difference is that in the fluid laying device  5 , the cleaning circuit is used to clean around the channel inlet and the channel outlets of the flow cell carrier. The cleaning circuit and the fluid laying circuit for the reagent to enter and exit the low cell carrier are independent of and do not communicate with each other. 
     The fluid laying device  5  includes a manifold block  51 . The manifold block  51  defines a first channel  511  and a second channel  512 . The first channel  511  allows a reagent pass through for laying of fluid on the flow cell carrier, thereby forming a fluid laying circuit. The second channel  512  allows a cleaning fluid to pass through to clean the sealing ring  52  and the periphery of the channel inlet and the channel outlets of the flow cell carrier, thereby forming a cleaning circuit. The manifold block  51  defines a plurality of openings, including a first fluid inlet  513 , a first fluid outlet  514 , a second fluid inlet  515 , a second fluid outlet  516 , and a plurality of valve connection ports  517 . The manner in which the valve connection ports are connected to a valve device (not shown) and the manner in which the fluid is controlled by the valve device to flow in the first channel  511  is the same as that of the fluid laying device  2  and will not be repeated. The first channel  511  communicates with the first fluid inlet  513  and the first fluid outlet  514 , and further communicates with an upstream pump (not shown) through the first fluid inlet  513 . The second channel  512  communicates with the second fluid inlet  515  and the second fluid outlet  516 , and further communicates with a source of cleaning fluid (not shown) through the second fluid inlet  515  and a downstream pump (not shown) through the second fluid outlet  516 . The manifold block  51  is provided with a carrier interface  518  corresponding to each of the channel inlet and the channel outlets of the flow cell carrier. Each carrier interface  518  is used to install a sealing ring  52 . The structure of the sealing ring  2  is same as that of the sealing ring  44 . In the embodiment, the second channel  512  is divided into a plurality of sections, and two adjacent sections are connected through the carrier interface  518 . Specifically, a number of holes (not shown) are defined in the carrier interface  518 . At least one of the holes communicates with the first hole  521  of the sealing ring  52 , which is used to guide the fluid in the first channel  511  to enter the flow cell carrier through the first hole  521 , or to guide the fluid in the flow cell carrier to enter the first channel  511  through the first hole  521 . At least two of the holes are used to communicate with adjacent sections of the second channel  512  and also communicate with the second hole  522  of the sealing ring  52 . Thus, the fluid in the second channel  512  passes through and cleans the sealing ring  52  and the periphery of the channel inlet and channel outlets of the flow cell carrier. 
     The fluid laying process on the flow cell carrier when using the fluid laying device  5  is as follows. 
     After the flow cell carrier is transferred and installed on the fluid laying device  5 , each of the channel inlet and channel outlets of the flow cell carrier is aligned with the first hole  521  of the corresponding sealing ring  52 . The sealing rings  52  seals the flow cell carrier. The fluid laying process is started, which can refer to the fluid laying process in other embodiments above and not repeated. 
     The cleaning process when using the fluid laying device  5  to clean the sealing ring  52  and the periphery of the channel inlet and the channel outlets of the flow cell carrier is as follows. 
     After the fluid laying is completed or before the next fluid laying is started, the downstream pump is started. After the cleaning fluid as the fluid from the cleaning fluid source enters the second fluid inlet  515  of the manifold block  51 , the cleaning fluid flows through the sections of the second channel  512  in sequence and fills the cleaning circuit, so that the sealing ring  52  and the channel inlet and channel outlets of the flow cell carrier are immersed and cleaned by the cleaning fluid. The cleaning process is applied for a period of time, such as three to ten seconds, and then the downstream pump is closed to stop the cleaning process. 
     The fluid laying device  5  also includes a support table (not shown) and a carrier mounting table (not shown), the configurations and functions are those of the fluid laying device  2  and will not be repeated. 
     Referring to  FIG.  12   , a fluid laying device is shown according to a third embodiment of the present disclosure. The hardware structure of the fluid laying device  6  in the embodiment is basically the same as that of the fluid laying device  2 , which also includes a support table, a carrier mounting table, and a manifold block. The configurations and functions of the support table and the carrier mounting table are the same as those of the fluid laying device  2  and will not be repeated. The difference between the fluid laying device  6  and the fluid laying device  2  is in the pipelines inside the manifold block. In the embodiment, the manifold block  61  of the fluid laying device  6  has three channels. The first channel  611  allows a reagent to pass through to realize fluid laying on the flow cell carrier, thereby forming a fluid laying circuit. The second channel  612   a  and the third channel  612   b  allow a cleaning fluid to pass through to clean the periphery of the channel inlet and the channel outlets of the flow cell carrier, thereby forming a cleaning circuit. The cleaning circuit and the fluid laying circuit are independent of and do not communicate with each other. 
     The manifold block  61  defines a number of openings, including a first fluid inlet  613 , a first fluid outlet  614 , a second fluid inlet  615 , a second fluid outlet  616 , and a number of valve connection ports  617 . In the embodiment, the manner in which the valve connecting ports  617  is connected to the valve device  618  and the manner in which the fluid is controlled by the valve device to flow in the first channel  611  to achieve fluid laying are the same as those of the fluid laying device  2  and will not be repeated. Two ends of the first channel  611  communicate with the first fluid inlet  613  and the first fluid outlet  614 , and further communicate with the upstream pump (not shown) and the reagent fluid source (not shown) through the first fluid inlet  613 . The first channel  611  further communicates with the downstream waste fluid storage unit (not shown) through the first fluid outlet  614 . The second channel  612   a  and the third channel  612   b  communicate with the second fluid inlet  615  and the second fluid outlet  616  respectively. The second fluid inlet  615  communicates with the upstream pump and the cleaning fluid source (not shown), and the second fluid outlet  616  communicate with the downstream pump (not shown) and the waste fluid storage unit (not shown). The manifold block  61  is provided with a carrier interface  619  corresponding to each of the channel inlet and the channel outlets of the flow cell carrier. The carrier interface  619  is used to install a sealing ring  62 . The structure of the sealing ring  62  is the same as that of the sealing ring  44 . The second channel  612   a  and the third channel  612   b  communicate with each other through the carrier interface  619 . Specifically, a number of holes are defined in the carrier interface  619 . At least one of the holes communicates with the first hole  621  of the sealing ring  62 , and is used to guide the fluid in the first channel  611  to enter the flow cell carrier through the first hole  621 , or to guide the fluid in the flow cell carrier to enter the first channel  611  through the first hole  621 . At least two of the holes communicate with the second channel  612   a  and the third channel  612   b.  Thus the cleaning fluid enters the carrier interface  619  from the second channel  612   a,  immerses and cleans the sealing ring  62  in the carrier interface  619  and the periphery of the channel inlet/outlet of the flow cell carrier, and then passes through the second channel  612   b  and exits the manifold block  61  through the second fluid outlet  616 . 
     The fluid laying process on the flow cell carrier when using the fluid laying device  6  is as already described and will not be repeated. 
     The cleaning process of using the fluid laying device  6  to clean the sealing ring  62  and the periphery of the channel inlet and the channel outlet of the flow cell carrier is as follows: 
     After the fluid laying is completed or before the treat fluid laying is started, the upstream pump and the downstream pump are started. After the cleaning fluid as the fluid from the cleaning fluid source enters the second fluid inlet  615  of the manifold block  61 , the cleaning fluid flows through the second channel  612   a,  the carrier interface  619 , and the third channel  612   b  in sequence, and fills the cleaning circuit, so that the sealing ring  52  and the periphery of the channel inlet and the channel outlets of the flow cell carrier e immersed and cleaned by the cleaning fluid. The cleaning process is applied for a period of time, three to ten seconds, and then the upstream pump and the downstream pump are turned off to stop the cleaning process. The flow cell carrier is removed. The downstream pump is started to discharge residual fluid at the sealing ring  62  through the third flow passage  612   b  and the second fluid outlet  616 . 
     A fourth embodiment of a fluid laying device is also provided according to the present disclosure. In the fourth embodiment, the fluid laying device an the flow cell carrier are integrated as a whole, and the manifold block of the fluid laying device constitutes a cover of the flow cell carrier. Specifically, the fluid laying device includes a support table, a carrier mounting table, and a manifold block. The carrier mounting table can be a certain area on the support table. In the embodiment, the carrier mounting table is disposed in the central area of the support table, and a base of the flow cell carrier is disposed on such area. The manifold block is placed above the base, and a certain area of the manifold block faces and is spaced apart from the base. In the embodiment, the base and the manifold block are separated and hermetically sealed from each other. For example, a sealing fence is hermetically disposed between the base and the manifold block, so as to form a channel between the base and the manifold block. In the embodiment, the central area of the manifold block and the base constitute the flow cell carrier. The manifold block defines a channel inlet and a number of channel outlets. Grooves are defined between the channel inlet and one channel outlet and/or between two channel outlets, which are used to guide the fluid in the channel to realize fluid laying. The manifold block is also provided with a carrier interface at a position corresponding to each of the channel inlet and the channel outlets. The channel inlet and the channel outlets are disposed at the bottom of the corresponding carrier interfaces. A sealing ring is installed in the carrier interface. The sealing ring is the sealing ring  26  or can be sealing ring  44  in the above embodiments. The manifold block also defines a first channel and a second channel (and may further define a third channel). The first channel constitutes a fluid laying circuit, and the second channel (or the second channel and the third channel) constitutes a cleaning circuit. A number of valve devices are also provided outside the manifold block, to communicate with the first channel. The fluid laying in the flow cell carrier is controlled by controlling the valve devices to open or be closed. The setting of the channel in the manifold block, each opening on the manifold block, and the valve devices can refer to the above embodiments of the present disclosure. At least two holes are also provided in the carrier interface to connect to the first channel and the second channel. The configuration of the holes in the carrier interface can also refer to the above embodiments of the present disclosure. In the embodiment, the manifold block is fixed to the support table by mechanical fastening such as screw locking, clamp clamping, etc. When the manifold block is fixed to the support table, the manifold block also tightly fixes the base of the flow cell carrier. 
     The fluid laying method using the fluid laying device according to an embodiment can refer to the above descriptions and will not be repeated. The cleaning method of the pipelines and sealing rings in the fluid laying device can also refer to the above embodiments and will not be repeated. 
     Referring to  FIG.  13   , a fluid laying system is shown according to a first embodiment of the present disclosure. The fluid laying system  7  in the embodiment includes a fluid laying device  71 . The flow cell carrier  72  can be installed on or removed front the fluid laying device  71  as required. For example, during the fluid laying process, the flow cell carrier  72  needs to be installed on the fluid laying device  71 . During the cleaning process, the flow cell carrier  72  can be kept on the fluid laying device  71  in a first case. At this time, the channel inlet and the channel outlet of the channel may also be cleaned together with the pipelines and the sealing rings of the fluid laying device  71 . The flow cell carrier  72  may also be removed from the fluid laying device  71  in a second case, and at this time, only the pipes and the sealing rings in the fluid laying device  71  are cleaned. The fluid laying device  71  may be any of the fluid laying devices described in the above embodiments, such as the fluid laying device  2 ,  5 , or  6 . 
     A fluid source  73  is provided upstream of the fluid laying device  71 . The fluid source  73  includes a reagent fluid source  731  and a cleaning fluid source  733 . The reagent fluid source  731  is used to provide a reagent for the fluid laying device  71  to realize fluid laying on the flow cell carrier  72 . The cleaning fluid source  733  is used to provide a cleaning fluid for cleaning the inner pipes of the fluid laying device  71 , the sealing rings, and the periphery of the channel inlet and the channel outlets of the flow cell carrier  72 . The reagent fluid source  731  communicates with a power device  741 , which is used to provide power for the reagent to enter and flow through the fluid laying device  71  and the flow cell carrier  72 . The power device  741  may be a pump. A valve device  751  is provided on the fluid path between the power device  741  and the fluid laying device  71 . The valve device  751  is used to control the fluid path between the power device  741  and the fluid laying device  71  to open or be closed. The cleaning fluid source  733  communicates with a power device  742 . The power device  742  is used to provide power for the cleaning fluid to enter the fluid laying device  71 . The power device  741  may be a pump. A valve device  752  is provided between the power device  742  and the fluid laying device  71 . The valve device  752  is used to control the power device  742  to connect to or disconnect from the fluid laying device  71 . 
     A waste fluid storage unit  76  is provided downstream of the fluid laying device  71 . The waste fluid storage unit  76  is used to store the waste fluid flowing out of the fluid laying device  71 . A power device  743  is provided between the waste fluid storage unit  76  and the fluid laying device  71 . The power device  743  may be a pump to provide power for the waste fluid in the fluid laying device  71  to flow into the waste fluid storage unit  76 . In the embodiment, a pneumatic unit  77  is further provided in the fluid laying system  7 , which is used to provide a low pressure (e.g., vacuum) to the carrier mounting table of the fluid laying device  71  to adsorb the flow cell carrier. The pneumatic unit  77  may be omitted in other embodiments in which the flow cell carrier is mounted to the fluid laying device  71  by mechanical fastening. A control device  78  is further provided in the fluid laying system  7 , this may be a collection of hardware devices and software for controlling the power devices  741 - 743 , the valve devices  751  and  752 , the pneumatic unit  77 , and the valve device of the fluid laying device  71 . In one embodiment, the control device  78  may be a computer device including a processing unit, a storage unit, and computer programs. The computer programs are stored in the storage unit and executed by the processing unit, thereby allowing the control device  78  to control the power devices  741 - 743 , the valve devices  751  and  752 , the pneumatic unit  77 , and the valve devices of the fluid laying device  71 . 
     Referring to  FIG.  14   , a fluid laying system is shown according to a second embodiment of the present disclosure. The fluid laying system  8  in the embodiment can be used to perform the fluid laying process or the cleaning process. Therefore, compared with the fluid laying system  7  in the first embodiment, the fluid laying system  8  includes a functional device  81 , which is a fluid laying device or a cleaning device. A flow cell carrier  82  is mounted on the functional device  81 . A fluid source  83  is provided upstream of the functional device  81 . The fluid source  83  can output a reagent or a cleaning fluid. A power device  84  and a valve device  85  are provided between the fluid source  83  and the functional device  81 , in that order. The configurations downstream of the functional device  81  and other configurations are as for those of the fluid laying system  7  and will not be repeated. 
     The functional device  81  can be one of a fluid laying device and a cleaning device. 
     In practical use, the fluid laying device and method, the cleaning device and method, and fluid laying system provided in the present disclosure can be used in some links of molecular diagnosis or in vitro diagnosis requiring fluid laying and subsequent cleaning. For example, they can be applied to nucleic acid sequencing. Nucleic acid samples or reagents are evenly laid in the flow cell carrier. After the fluid laying process, pipes and sealing rings of the fluid laying device and/or the channel inlet and outlets of the flow cell carrier are cleaned. 
     The fluid laying device, fluid laying method, and fluid laying system provided in the present disclosure uses a positive pressure for laying of fluid to significantly improve the fluid laying speed and reduce the possibility of bubbles on the flow cell carrier. They can be applied to the fluid laying of flow cell carriers with large size and small aspect ratio, and can significantly improve the efficiency of replacement among reagents that enter the flow cell carriers in sequence and the uniformity of a fluid layer. The cleaning device and method provided increase the maintainability and reliability of the fluid laying device, significantly improve the service life of the device, and reduce the failure rate of the device. 
     It can be understood that some technical details or features of the above-mentioned embodiments of the fluid laying device and method, the cleaning device and method, and the fluid laying system of the present disclosure can be mutually referenced or replaced. For example, the sealing ring  26  of the fluid laying device  2  according to the first embodiment be replaced by the sealing ring  44  of the cleaning device  4  from another embodiment. 
     It can be understood that although the above embodiments of the present disclosure describe the valve devices as being disposed on the outside of the manifold block, each valve device can also be disposed on the inside of the manifold block so long as the valve devices remain on the corresponding fluid path. 
     It can be understood that the above embodiments of the present disclosure describe the sealing ring as being installed in the carrier interface and the carrier interface and the sealing ring as independent components. In practice, the sealing ring can also be integrated with the corresponding carrier interface, or the sealing ring can form a part of the corresponding carrier interface. 
     It can be understood that the manifold block of the fluid laying device is a single unit when the fluid laying device is described in the above embodiment. In practice, the manifold block of the fluid laying device can also be composed of multiple sub-blocks. For example, the fluid laying device, when referring to the cleaning device, can have the manifold block composed of multiple sub-blocks, and the sub-blocks can be connected by pipes. The inlet valve devices and the outlet valve devices can be set on the corresponding sub-blocks. The bypass valve device can be set on a certain sub-block or on the pipeline connecting the sub-block. 
     It can be understood that the manifold block of the cleaning device is composed of sub-blocks in the descriptions of the cleaning device in the above embodiments. However, the manifold block of the cleaning device can also be a single unit. The cleaning circuit runs through the manifold block, and the fluid inlet and the fluid outlet are connected at both ends of the cleaning circuit. 
     It can be understood that the fluid laying device and the cleaning device described in the above embodiments can be described as fluid passage devices. Both of the fluid laying device and the cleaning device use a manifold block having a valve device and a carrier interface to control and guide the fluid. By providing a first hole only or a first hole and a second hole on the carrier interface, the fluid laying and the cleaning process can be realized. Specifically, the manifold block can be provided with a channel. The manifold block is provided with a fluid inlet, a fluid outlet, and a carrier interface communicating with the channel. The carrier interface is used to communicate with the channel in the flow cell carrier when the flow cell carrier is installed on the fluid passage device. The carrier interface has a first hole and a second hole. The second hole in the carrier interface is connected to the channel through a fluid path. The first hole in the carrier interface is connected to the channel through a fluid path, and is used to communicate with the channel in the flow cell carrier when the flow cell carrier is mounted on the fluid passage device. The fluid entering the channel from the fluid inlet enters and exits the flow cell carrier through the first hole of the carrier interface, and then flows out through the fluid outlet. Alternatively, the fluid entering the channel from the fluid inlet can enter the carrier interface through the first hole of the carrier interface, then enter the channel through the second hole of the carrier interface, and flow out from the fluid outlet. Alternatively, the fluid entering the channel from the fluid inlet further can enter and exit the carrier interface through the second hole, and then flow out through the fluid outlet. 
     It can be understood that the fluid laying device and the auxiliary cleaning tool described in the above embodiments can be described as a composite device. Before cleaning some components, the auxiliary cleaning tool is placed on the fluid laying device to assist in cleaning some components of the fluid laying device. 
     Finally, even though information and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the present embodiments, the disclosure is illustrative only. Changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the present exemplary embodiments, to the full extent indicated by the plain meaning of the terms in which the appended claims are expressed.