Rotary valve and experimental system with same

Abstract

The utility model discloses a rotary valve and an experiment system with the rotary valve, the rotary valve provided by the utility model has four rotary positions, liquid at different positions in the four positions flows out from the same waste liquid interface on a first valve body, interfaces on the outer surface of the first valve body are simplified, the number of the interfaces on the first valve body is only seven, and the number of the interfaces on the first valve body is greatly reduced. The first valve body can achieve the same function as a rotary valve with eight or more connectors in the prior art, and the first valve body is simple in structure and low in manufacturing cost.

Description

Technical Field

[0001] This application relates to the field of fluid equipment technology, and in particular to a rotary valve and an experimental system having the rotary valve. Background Technology

[0002] Rotary valves of various structures are commonly used in liquid chromatography analysis systems to meet experimental requirements. Since these systems typically require multiple functions, the rotary valves used are generally quite complex, with some having as many as eight or more external structures. This complexity increases the difficulty of manufacturing and consequently raises production costs.

[0003] Therefore, how to simplify the structure of rotary valves and reduce experimental costs has always been a technical issue of concern to those skilled in the art. Utility Model Content

[0004] One objective of this application is to provide a rotary valve with a relatively simple structure and low operating cost. Another objective of this application is to provide an experimental system incorporating this rotary valve.

[0005] This application provides a rotary valve, including a first valve body and a second valve body capable of relative rotation; the first valve body has a connecting surface and a first mating surface, the connecting surface being provided with a first injection port (syr), a second injection port (syp), a sample pump port (sap), a chromatography column port (col), a waste liquid port (w), a first sample loop port (loopf), and a second sample loop port (loope); the mating surface has a first opening, a second opening, a third opening, a fourth opening, a fifth opening, and a sixth to a seventh opening that correspond one-to-one with the first injection port (syr), the second injection port (syp), the sample pump port (sap), the chromatography column port, the waste liquid port, the first sample loop port, and the second sample loop port and are connected through the interior of the first valve body; wherein the number of waste liquid ports is one, the fifth opening includes a first groove segment and a second groove segment connected together, the first groove segment having at least two points located on the same diameter, and the second groove segment extending radially along the first valve body.

[0006] The second valve body is provided with a first flow channel, a second flow channel, a third flow channel, a fourth flow channel and a fifth flow channel, and each flow channel is not connected to the others;

[0007] The second valve body can rotate relative to the first valve body to a first position, a second position, a third position, and a fourth position;

[0008] When the second valve body is in the first position, the second liquid injection port is connected to the chromatography column port through the second flow channel, the first liquid injection port is connected to the first sample ring port through the fourth flow channel, and the second sample ring port is connected to the waste liquid port through the first flow channel and the first tank section.

[0009] When the second valve body is in the second position, the second liquid injection port is connected to the second sample ring port through the second flow channel, and the first sample ring port is connected to the chromatography column port through the fourth flow channel; the first flow channel is connected to the first tank section so that the sample pump port is connected to the waste liquid port.

[0010] When the second valve body is in the third position, the second flow channel is connected to the second tank section, so that the second liquid injection port is connected to the waste liquid port; the chromatography column port is connected to the sample pump port through the fourth flow channel.

[0011] When the second valve body is in the fourth position, the second liquid injection port is connected to the chromatography column port through the second flow channel; the sample pump port is connected to the first sample ring port through the fifth flow channel, and the third flow channel is connected to the second tank section, so that the second sample ring port is connected to the waste liquid port.

[0012] The rotary valve provided in this application has four rotation positions, and the liquid in each of the four positions flows out from the same waste liquid port on the first valve body. This simplifies the ports on the outer surface of the first valve body. The first valve body has only seven ports, which can achieve the same function as the rotary valve with eight or more ports in the current first valve body. The first valve body of this application has a simple structure and a relatively low manufacturing cost.

[0013] In one example, the first groove segment is an arc-shaped segment.

[0014] Alternatively, the second slot segment is a straight segment.

[0015] In one example, the second flow channel is a straight groove passing through the rotation center of the second valve body, and the second flow channel includes a first diameter segment and a second diameter segment located on both sides of the rotation center;

[0016] When the second valve body is in the first position, the second liquid injection port is connected to the chromatography column port through the first diameter section;

[0017] When the second valve body is in the second position, the second liquid injection port is connected to the second sample ring port through the first diameter section;

[0018] When the second valve body is in the third position, the first diameter section is connected to the second groove section;

[0019] When the second valve body is in the fourth position, the second injection port is connected to the chromatography column port through the second diameter section.

[0020] In one example, the first flow channel and the fourth flow channel are arranged symmetrically about the second flow channel.

[0021] In one example, the first opening, the second opening, the third opening, the fourth opening, the fifth opening, and the sixth to seventh openings all have segments located on the same diameter;

[0022] Alternatively / and, the first to fifth flow channels are grooves provided on the end face of the second valve body.

[0023] In one example, the fifth flow channel is a groove disposed on the mating surface of the second valve body and the first valve body, and both ends of the groove are located on both sides of the second flow channel and the third flow channel.

[0024] In one example, the fifth flow channel includes two notches formed on the end face of the second valve body, and the two notches are connected through the interior of the second valve body.

[0025] In one example, the two notches of the fifth flow channel are located on both sides of the first flow channel and the second flow channel.

[0026] In one example, the third flow channel is a straight groove.

[0027] This application also provides an experimental system including a system pump, a sample pump, a chromatography column and a sample loop, and a rotary valve as described in any of the above claims.

[0028] The experimental system of this application has the rotary valve described in any of the above embodiments, and therefore the experimental system also has the above-mentioned technical effects of the rotary valve. Attached Figure Description

[0029] Figure 1 A schematic diagram of one embodiment of the testing system provided in this application;

[0030] Figure 2 for Figure 1 A schematic diagram of the rotary valve in the experimental system shown.

[0031] Figure 3 for Figure 2 A top view of the first valve body from the direction of its self-fitting surface; the dashed lines in the figure represent the main internal channel structure of the first valve body.

[0032] Figure 4 for Figure 3 A non-perspective schematic diagram of the structure shown;

[0033] Figure 5 This is a three-dimensional schematic diagram of the second valve body in one embodiment of this application;

[0034] Figure 6 for Figure 2 A top view of the structure shown;

[0035] Figures 7 to 10 for Figure 2 The diagram shows perspective views of the second valve body in the first, second, third, and fourth positions of the rotary valve. It mainly shows perspective views of the mating flow channels in the first and second valve bodies, as well as the flow path of the fluid.

[0036] Figure 11 This is a schematic diagram of the structure of the second valve body in another embodiment of this application.

[0037] The one-to-one correspondence between the reference numerals and components in the attached drawings is as follows:

[0038] 100 Rotary valve; 200 Sample loop; 300 Chromatography column; 400 Syringe; 501 First pump; 502 Second pump; 503 Third pump; 600 Waste liquid storage device; 701 First reversing valve; 702 Second reversing valve; 703 Third reversing valve;

[0039] 1. First valve body; 11' First liquid injection port; 12' Second liquid injection port; 13' Sample pump port; 14' Chromatography column port; 15' Waste liquid port; 16' First sample loop port; 17' Second sample loop port; 11 First port; 12 Second port; 13 Third port; 14 Fourth port; 15 Fifth port; 151 First tank segment; 152 Second tank segment; 16 Sixth port; 17 Seventh port; 11A First channel; 12A Second channel; 13A Third channel; 14A Fourth channel; 15A Fifth channel; 16A Sixth channel; 17A Seventh channel; 101 Connecting surface; 102 Mating surface;

[0040] 2 Second valve body; 210 Second mating surface; 21 First flow channel; 22 Second flow channel; 23 Third flow channel; 24 Fourth flow channel; 25 Fifth flow channel; 251 First notch; 252 First notch; 25A First section; 25B ​​Second section. Detailed Implementation

[0041] To enable those skilled in the art to better understand the technical solutions of this application, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0042] This article uses the application of a rotary valve in a liquid chromatography analysis experimental system as an example to introduce the technical solution and its effects. Those skilled in the art should understand that the rotary valve in this application can also be applied to other systems.

[0043] Please refer to Figures 1 to 10 , Figure 1 A schematic diagram of one embodiment of the testing system provided in this application; Figure 2 for Figure 1 A schematic diagram of the rotary valve in the experimental system shown. Figure 3 for Figure 2 A top view of the first valve body from the direction of its self-fitting surface; the dashed lines in the figure represent the main internal channel structure of the first valve body. Figure 4 for Figure 3 A non-perspective schematic diagram of the structure shown; Figure 5 This is a three-dimensional schematic diagram of the second valve body in one embodiment of this application; Figure 6 for Figure 2 A top view of the structure shown; Figures 7 to 10 for Figure 2 The diagram shows perspective views of the second valve body in the rotary valve in the first, second, third, and fourth positions. It mainly shows perspective views of the mating flow channels in the first and second valve bodies, as well as the flow path of the fluid.

[0044] This application provides an experimental system comprising at least a system pump, a sample pump, a chromatography column 300, a sample loop 200, and a rotary valve 100. The number of system pumps can be one or more, depending on the specific experimental requirements. While the specific structures of the system pump and sample pump are not described herein, this does not preclude those skilled in the art from understanding the technical solution described herein.

[0045] The system pump is mainly used to provide the power for the flow of sample liquid in the experimental system.

[0046] This application provides a rotary valve, comprising a first valve body 1 and a second valve body 2 capable of relative rotation, that is, the second valve body 2 can rotate about the rotational axis of the two. The second valve body 2 can be a cylindrical structure. The second valve body 2 can be partially located inside the first valve body 1, i.e., the first valve body 1 has an inner cavity, and the second valve body 2 can be partially or completely located within the inner cavity of the first valve body 1, with the first valve body 1 and the second valve body 2 rotating circumferentially in cooperation. The external shapes of the first valve body 1 and the second valve body 2 can be designed as needed, and are not specifically limited herein.

[0047] Of course, the second valve body 2 can also be located completely outside the first valve body 1.

[0048] In this embodiment, the first valve body 1 has a connecting surface and a first mating surface. The connecting surface is provided with a first liquid injection port 11', a second liquid injection port 12', a sample pump port 13', a chromatography column port 14', a waste liquid port 15', a first sample loop port 16', and a second sample loop port 17'. The first liquid injection port 11' is used to connect to a first liquid injection component, which can be a quantitative solution injection component, such as a syringe 400. The operator can use the syringe 400 to deliver a small amount of liquid sample into the sample loop 200 through the rotary valve 1. The second liquid injection port 12' can be connected to the aforementioned system pump. The system pump is connected to the second liquid injection port through pipes, two-way valves, or three-way valves, etc. Figure 1 The system is shown to have three pumps: pump 501, pump 502, and pump 503. Each pump's inlet is connected to a directional control valve: directional control valve 701, directional control valve 702, and directional control valve 703. Figure 1 In the diagram, A1, A2, B1, B2, C1, and C2 represent the connected liquid pipelines. The sample pump interface connects to the sample pump. The first sample loop interface and the second sample loop interface connect to the two ends of the sample loop, respectively. The chromatography column interface 14' connects to the chromatography column 300, and the waste liquid interface 15' connects to the waste liquid pipeline, on which a waste liquid storage device 600 can be installed.

[0049] In this embodiment, the mating surface 102 of the first valve body 1 has a first opening 11 to a seventh opening 17, which are respectively connected to the first liquid injection port 11', the second liquid injection port 12', the sample pump port 13', the chromatography column port 14', the waste liquid port 15', the first sample ring port 16', and the second sample ring port 17'. That is, the first liquid injection port 11' is connected to the first opening 11 through the first channel 11A inside the first valve body 1, and the second liquid injection port 12' is connected to the first opening 11 through the second channel 12A inside the first valve body 1. The second opening 12 is connected, the sample pump interface 13' is connected to the third opening 13 through the third channel 13A inside the first valve body 1, the chromatography column interface 14' is connected to the fourth opening 14 through the fourth channel 14A inside the first valve body 1, the waste liquid interface 15' is connected to the fifth opening 15 through the fifth channel 15A inside the first valve body 1, the first sample ring interface 16' is connected to the sixth opening 16 through the sixth channel 16A inside the first valve body 1, and the second sample ring interface 17' is connected to the seventh opening 17 through the seventh channel 17A inside the first valve body 1. Each channel from the first channel 11A to the seventh channel 17A is independent of the others. As shown in the figure, the internal channels of the first valve body 1 can have the same shape or different shapes.

[0050] As described above, the connecting surface 101 is mainly used to set the connection port with external equipment and pipelines such as the system pump, sample pump, chromatography column 300, sample loop 200, and syringe 400. The connecting surface 101 is usually the outer surface of the first valve body 1.

[0051] Each interface on the connection surface 101 can be set in a suitable position, as long as it can reliably connect with other components. In order to improve the reliability of the connection pipeline and improve the connection efficiency, the interfaces of each interface unit can be marked.

[0052] In this embodiment of the application, there is one waste liquid interface 15'. The fifth opening 15 includes a first groove segment 151 and a second groove segment 152 connected together. The first groove segment 151 has at least two points located on the same diameter, and the second groove segment 152 extends radially along the first valve body 1.

[0053] In this application, the second valve body 2 is provided with a first flow channel 21, a second flow channel 22, a third flow channel 23, a fourth flow channel 24 and a fifth flow channel 25, and each flow channel is not connected to the others; that is, each flow channel is independent of the others.

[0054] The second valve body 2 of this application can rotate relative to the first valve body 1 to a first position, a second position, a third position, and a fourth position.

[0055] Please refer to Figure 7 When the second valve body 2 is in the first position, the second injection port is connected to the chromatography column port through the second flow channel 22. The sample flow path is: system pump → second injection port 12' → second opening 12 → second flow channel 22 → fourth opening 14 → chromatography column port → chromatography column. At the same time, the first injection port 11' is connected to the first sample ring port through the fourth flow channel 24, and the second sample ring port 17' is connected to the waste liquid port through the first flow channel 21 and the first tank section 151. The flow path of the liquid in the first injection port is: syringe 400 → first injection port 11' → first opening 11 → first sample ring port 16' → sample ring → second sample ring port 17' → first tank section 151 → first tank section 151 of the fifth opening 15 → waste liquid port → waste liquid pipeline.

[0056] In short, in the first position, the syringe 400 can inject a quantitative amount of sample into the sample loop through the rotary valve 100, and discharge waste liquid from the sample loop through the rotary valve 100. Simultaneously, the system pump can inject specific liquids into the chromatography column through the rotary valve 100.

[0057] Please refer to Figure 8When the second valve body 2 is in the second position, the second injection port 12' is connected to the second sample ring port 17' through the second flow channel 22, and the first sample ring port 16' is connected to the chromatography column port 14' through the fourth flow channel 24. The flow path of the liquid in the system pump is: system pump → second injection port 12' → second opening 12 → second flow channel 22 → second sample ring port 17' → sample ring 200 → first sample ring port 16' → fourth flow channel 24 → chromatography column port 14'. At the same time, the first flow channel 21 is connected to the first tank section 151 so that the sample pump port is connected to the waste liquid port. That is to say, the liquid in the sample pump can flow to the waste liquid pipeline through the rotary pump. The flow path is: sample pump → sample pump port → first flow channel 21 → first tank section 151 of the fifth opening 15 → waste liquid port 15' → waste liquid pipeline.

[0058] In short, in the second position, the liquid in the sample pump can be discharged to the waste liquid line through the rotary valve 100, while the system pump can feed the sample onto the chromatography column through the sample loop.

[0059] Please refer to Figure 9 When the second valve body 2 is in the third position, the second flow channel 22 is connected to the second tank section 152 so that the second liquid injection port is connected to the waste liquid port; the chromatography column port is connected to the sample pump port through the fourth flow channel 24; the system pump can flush the corresponding flow channel in the rotary valve 100, and the sample pump can load the chromatography column.

[0060] Please refer to Figure 10 When the second valve body 2 is in the fourth position, the second liquid injection port is connected to the chromatography column port through the second flow channel 22. The liquid flow path is: system pump → second liquid injection port → second opening 12 → second flow channel 22 → fourth opening 14 → chromatography column port → chromatography column. At the same time, the sample pump port is connected to the first sample ring port through the fifth flow channel 25, and the third flow channel 23 is connected to the second tank section 152 so that the second sample ring port is connected to the waste liquid port.

[0061] In short, in position four, the liquid in the sample pump can be discharged to the waste liquid line via rotary valve 100. Simultaneously, the system pump can fill the chromatography column with liquid.

[0062] The flow rate of fluid through the rotary valve at each position can be controlled by a flow valve (not shown in the figure) installed on the corresponding pipeline.

[0063] As can be seen from the above description, the rotary valve 100 provided in this application has four rotation positions. Liquids in different positions flow out from the same waste liquid port on the first valve body 1. This simplifies the ports on the outer surface of the first valve body 1. The first valve body 1 has only seven ports, which can achieve the same function as the rotary valve 100 with eight or more ports in the current first valve body 1. The first valve body 1 of this application has a simple structure and a relatively low manufacturing cost.

[0064] In this embodiment, the first groove segment 151 can be an arc-shaped segment with a predetermined length, which facilitates docking with other openings. Of course, the first groove segment 151 can also be other forms of curved segments, as long as the above-mentioned functions can be achieved.

[0065] In this embodiment, the second groove segment 152 is a straight segment, which is simple to process. Of course, the second groove segment 152 can also be a non-straight segment, such as a curved and extended groove segment.

[0066] In this embodiment, the second flow channel 22 is a straight groove passing through the rotation center of the second valve body 2. The second flow channel 22 includes a first diameter section and a second diameter section located on both sides of the rotation center. When the second valve body 2 is in the first position, the second liquid injection port is connected to the chromatography column port through the first diameter section. When the second valve body 2 is in the second position, the second liquid injection port is connected to the second sample ring port through the first diameter section. When the second valve body 2 is in the third position, the first diameter section is connected to the second groove section 152. When the second valve body 2 is in the fourth position, the second liquid injection port is connected to the chromatography column port through the second diameter section.

[0067] In this embodiment, the straight groove can achieve the functions required for the above four positions, and the processing is simple and easy.

[0068] In this embodiment, the first opening 11, the second opening 12, the third opening 13, the fourth opening 14, the fifth opening 15, the sixth opening 16, and the seventh opening 17 all have sections located on the same diameter, which facilitates processing and rotation to achieve the above-mentioned functions. Correspondingly, the interface on the end face of the second valve body 2 that communicates with each opening should also cover a portion of the corresponding opening area.

[0069] The first flow channel 21 and the fourth flow channel 24 are arranged symmetrically about the second flow channel 22. The first flow channel 21 and the fourth flow channel 24 can be a V-shaped structure, an arc-shaped structure, or an S-shaped structure.

[0070] The fifth flow channel 25 includes two notches formed on the end face of the second valve body 2, namely the first notch 251 and the second notch 252. The two notches are connected through the interior of the second valve body 2. This can simplify the structure on the end face of the second valve body 2 as much as possible, provide space for the arrangement of other flow channels, and help improve the structural strength of the end face, thereby improving the overall strength of the rotary valve 100. Figure 5 The diagram shows that the fifth flow channel 25 is a V-shaped structure comprising the first section 251 and the second section 252, which is simple in structure and easy to manufacture. Of course, the fifth flow channel 25 can also have other structural forms.

[0071] In one specific embodiment, the two notches of the fifth flow channel 25 are located on both sides of the first flow channel 21 and the second flow channel 22.

[0072] In the above embodiments, the third flow channel 23 is a straight groove, which has a relatively simple structure and is easy to implement.

[0073] In another specific embodiment, please refer to Figure 11 , Figure 11 This is a schematic diagram of the structure of the second valve body in another embodiment of this application. The first to fifth flow channels can all be grooves provided on the end face of the second valve body for easy processing. The structure of the first to fourth flow channels is similar to... Figure 5 The embodiment shown is the same, except that in this embodiment, the fifth flow channel is located on the end face of the second valve body. The distance from the two end notches of the fifth flow channel to the central axis is... Figure 5 The two notches are approximately equidistant from the central axis.

[0074] The shape of each flow channel and each opening in this application is not limited to the above description, as long as it can meet the required functions of the above four positions.

[0075] The experimental system in this application embodiment has the rotary valve described in any of the above embodiments, so the experimental system also has the above-mentioned technical effects of the rotary valve.

[0076] The present application provides a detailed description of a rotary valve and an experimental system incorporating the rotary valve. Specific examples have been used to illustrate the principles and implementation methods of the present application. The descriptions of these embodiments are merely illustrative and are intended to aid in understanding the method and core concepts of the present application. It should be noted that those skilled in the art can make various improvements and modifications to the present application without departing from its principles, and these improvements and modifications also fall within the scope of protection of the claims.

Claims

1. A rotary valve, characterized in that The valve comprises a first valve body and a second valve body capable of relative rotation; the first valve body has a connecting surface and a first matching surface, the connecting surface is provided with a first liquid injection interface, a second liquid injection interface, a sample pump interface, a chromatographic column interface, a waste liquid interface, a first sample ring interface and a second sample ring interface; the matching surface has a first opening, a second opening, a third opening, a fourth opening, a fifth opening, a sixth opening to a seventh opening corresponding to the first liquid injection interface, the second liquid injection interface, the sample pump interface, the chromatographic column interface, the waste liquid interface, the first sample ring interface and the second sample ring interface, and the first valve body is internally communicated; wherein the number of waste liquid interfaces is one, the fifth opening comprises a first groove segment and a second groove segment connected thereto, the first groove segment has at least two points on the same diameter, and the second groove segment extends along the radial direction of the first valve body; the second valve body is provided with a first flow channel, a second flow channel, a third flow channel, a fourth flow channel and a fifth flow channel, and each flow channel is not communicated with each other; the second valve body can be rotated to a first position, a second position, a third position and a fourth position relative to the first valve body; when the second valve body is in the first position, the second liquid injection interface is communicated with the chromatographic column interface through the second flow channel, the first liquid injection interface is communicated with the first sample ring interface through the fourth flow channel, and the second sample ring interface is communicated with the waste liquid interface through the first flow channel and the first groove segment; when the second valve body is in the second position, the second liquid injection interface is communicated with the second sample ring interface through the second flow channel, and the first sample ring interface is communicated with the chromatographic column interface through the fourth flow channel; the first flow channel is communicated with the first groove segment, so that the sample pump interface is communicated with the waste liquid interface; when the second valve body is in the third position, the second flow channel is communicated with the second groove segment, so that the second liquid injection interface is communicated with the waste liquid interface; the chromatographic column interface is communicated with the sample pump interface through the fourth flow channel; when the second valve body is in the fourth position, the second liquid injection interface is communicated with the chromatographic column interface through the second flow channel; the sample pump interface is communicated with the first sample ring interface through the fifth flow channel, and the third flow channel is communicated with the second groove segment, so that the second sample ring interface is communicated with the waste liquid interface.

2. The rotary valve of claim 1, wherein the first groove segment is an arc segment, or / and, the second groove segment is a straight line segment.

3. The rotary valve of claim 2, wherein the second flow channel is a straight line groove passing through the rotation center of the second valve body, and the second flow channel comprises a first radial segment and a second radial segment located on both sides of the rotation center; when the second valve body is in the first position, the second liquid injection interface is communicated with the chromatographic column interface through the first radial segment; when the second valve body is in the second position, the second liquid injection interface is communicated with the second sample ring interface through the first radial segment; when the second valve body is in the third position, the first radial segment is communicated with the second groove segment; When the second valve body is in the fourth position, the second liquid injection interface communicates with the chromatographic column interface through the second radial section.

4. The rotary valve of claim 3 wherein, The first flow channel and the fourth flow channel are symmetrically arranged relative to the second flow channel.

5. A rotary valve as claimed in any one of claims 1 to 4, characterised in that, The first opening, the second opening, the third opening, the fourth opening, the fifth opening, the sixth opening to the seventh opening all have sections on the same diameter. Alternatively or additionally, the first flow channel to the fifth flow channel are grooves provided on the end face of the second valve body.

6. A rotary valve as claimed in any one of claims 1 to 4, characterised in that, The fifth flow channel is a groove provided on the mating face of the second valve body and the first valve body, and both ends of the groove are located on both sides of the second flow channel and the third flow channel.

7. A rotary valve as claimed in any one of claims 1 to 4, characterised in that, The fifth flow channel includes two notches opened on the end face of the second valve body, and the two notches are communicated through the inside of the second valve body.

8. The rotary valve of claim 7, wherein The two notches of the fifth flow channel are located on both sides of the first flow channel and the second flow channel.

9. A rotary valve as claimed in any one of claims 1 to 4, characterised in that, The third flow channel is a straight-line groove.

10. An experimental system characterized by, The system further comprises a system pump, a sample pump, a chromatographic column and a sample loop, and further comprises the rotary valve according to any one of claims 1 to 9.

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