Multifunctional automatic sample injector

Abstract

The utility model relates to the technical field of liquid chromatography, in particular to a multifunctional automatic sample injector. Comprising a pump, a three-way piece, a sample injection valve, a chromatographic column, a detector, a sample injection assembly and a sample introduction device, the pump is communicated with the three-way piece, the three-way piece, the chromatographic column, the sample injection assembly and the sample introduction device are connected to the sample injection valve, and the end, away from the sample injection valve, of the chromatographic column is communicated with the detector; a first quantitative loop and a second quantitative loop are connected in the sample injection valve; switching the sample injection valve, and controlling two ends of the first quantitative loop to be communicated with the sample injection assembly and the sample introduction device respectively or communicated with the pump and the chromatographic column respectively; when the two ends of the first quantitative loop are communicated with the sample introduction assembly and the sample introduction device, the two ends of the second quantitative loop are respectively communicated with the pump and the chromatographic column; when the two ends of the first quantitative loop are respectively communicated with the pump and the chromatographic column, the two ends of the second quantitative loop are communicated with the sample introduction assembly and the sample introduction device; the cost is reduced, the sample injection is rapid, and the use error-tolerant rate of the high performance liquid chromatograph is improved.

Description

Technical Field

[0001] This utility model relates to the field of liquid chromatography technology, and in particular to a multifunctional automatic sampler. Background Technology

[0002] As a crucial module in liquid chromatography, the autosampler's injection accuracy, repeatability, and sample residue are undoubtedly important parameters. However, with the expanding applications of high-performance liquid chromatography (HPLC), the increasing sample throughput necessitates faster injection speeds, making this the next trend in instrument development. Simultaneously, the rapid development of the analytical instrument industry and the increasingly fast pace of work have made higher sample analysis efficiency a key metric for users when evaluating instruments. Therefore, higher fault tolerance has become a new goal pursued by professionals in related industries.

[0003] For rapid sample injection solutions, some instrument manufacturers focus on increasing the speed of each step in the injection process, such as increasing the needle movement speed and speeding up the needle cleaning process. While this approach can improve the injection speed to some extent, excessively fast movements may reduce the lifespan of various instrument components. Other instrument manufacturers use dual injection valves and dual injection needles to achieve rapid injection by switching flow paths. The main drawback is that dual injection valve-dual injection needle instruments are more expensive and, compared to single injection valve-single injection needle instruments, increase the potential points of failure for the instrument.

[0004] Meanwhile, regarding the error tolerance of high-performance liquid chromatography (HPLC), with more samples requiring analysis and more lab operators competing for positions, the probability of errors by newcomers during sample analysis increases significantly. Therefore, a higher instrument error tolerance greatly reduces system anomalies caused by human error, thereby significantly improving analytical efficiency. To address this, some instrument manufacturers have added numerous prompts to workstations, such as mobile phase volume and minimum sample volume estimates; others have simplified instrument operation procedures to reduce efficiency losses caused by operator unfamiliarity with the instrument. For autosamplers, the most common issue is incorrect placement of the target sample vial due to operator negligence. This results in no sample at the target location during injection, allowing air bubbles to enter the HPLC system and affecting subsequent sample analysis results. Incorrect sample tray specifications can also cause the injection needle to puncture the tray edge during injection, leading to irreversible damage such as bending or blockage, ultimately reducing sample analysis efficiency.

[0005] Therefore, there is an urgent need to provide a multifunctional autosampler that, compared with existing technologies, reduces costs, enables rapid sample injection, and improves the fault tolerance of high-performance liquid chromatography (HPLC). Utility Model Content

[0006] This invention addresses the technical problems existing in the prior art and provides a multifunctional automatic sampler.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0008] A multifunctional automatic sampler includes a pump, a three-way valve, an injection valve, a chromatographic column, a detector, an injection assembly, and a sample introduction device. The pump is connected to the three-way valve. The injection valve is connected to the three-way valve, the chromatographic column, the injection assembly, and the sample introduction device. The end of the chromatographic column away from the injection valve is connected to the detector. A first quantitative loop and a second quantitative loop are connected inside the injection valve.

[0009] Switch the injection valve to control the two ends of the first quantitative loop to be connected to the injection assembly and the sample introduction device, or to the pump and the chromatographic column, respectively; when the two ends of the first quantitative loop are connected to the injection assembly and the sample introduction device, the two ends of the second quantitative loop are connected to the pump and the chromatographic column, respectively; when the two ends of the first quantitative loop are connected to the pump and the chromatographic column, the two ends of the second quantitative loop are connected to the injection assembly and the sample introduction device, respectively.

[0010] Furthermore, the injection valve is a two-position ten-way injection valve, which includes a first port, a second port, a third port, a fourth port, a fifth port, a sixth port, a seventh port, an eighth port, a ninth port, and a tenth port. The third port and the ninth port are connected to the first quantitative loop, the first port and the fifth port are connected to the second quantitative loop, the second port is connected to the chromatographic column, the fourth port is connected to the injection assembly, the sixth port and the eighth port are both connected to the three-way connector, the tenth port is connected to the sample introduction device, and the seventh port is sealed with a plug.

[0011] Furthermore, the tee fitting is provided with a first connection port, a second connection port and a third connection port, the first connection port being connected to the pump, the second connection port being connected to the eighth interface, and the third connection port being connected to the sixth interface.

[0012] Furthermore, the pipes connecting the second connector and the eighth interface, and the pipes connecting the third connector and the sixth interface, are of the same length.

[0013] Furthermore, the end of the detector furthest from the chromatographic column is connected to a waste liquid container.

[0014] Furthermore, the injection assembly includes a motor, a fixed frame, an L-shaped plate, a threaded rod, a slider, and an injection needle. The motor and the L-shaped plate are fixedly connected to the fixed frame. The threaded rod is rotatably connected between the L-shaped plate and the fixed frame. The motor drives the threaded rod to rotate. The slider is threadedly connected to the threaded rod. When the threaded rod rotates, the slider moves along the vertical direction of the threaded rod. The injection needle is connected to the slider.

[0015] Furthermore, a clamping block is fixedly connected to the slider, the injection needle is connected to the clamping block, a probe is inserted through the clamping block, the upper end of the probe passes through the clamping block and is connected to a baffle, and a spring is fixedly connected between the baffle and the clamping block.

[0016] Furthermore, a baffle is fixedly connected to the lower end of the probe rod, and the baffle is provided with a through hole, into which the injection needle extends.

[0017] Furthermore, a U-shaped plate is fixedly connected to the upper wall of the clamping block, an indicator light is provided on the side wall of the U-shaped plate, an optocoupler switch is provided inside the U-shaped plate, the optocoupler switch is connected in series in the conduction circuit of the indicator light, the baffle is used to block the optocoupler switch, thereby controlling whether the optocoupler switch is conducting, and the indicator light is electrically connected to the controller.

[0018] Furthermore, the upper end of the threaded rod passes through the fixed frame, and the output end of the motor also passes through the fixed frame. A timing belt is fitted onto the output end of the motor and the upper end of the threaded rod.

[0019] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0020] (1) This utility model can complete rapid injection using a single injection valve and a single injection needle. Compared with the traditional dual injection valve and dual injection needle, it not only saves costs but also achieves rapid injection, improves the processing speed of the injector, and has fewer potential failure points.

[0021] (2) This utility model only requires switching the injection valve once each time the injection-analysis function is implemented. Compared with the conventional injection method which requires switching the injection valve at least twice, this increases the life of the injection valve, and even doubles the life.

[0022] (3) This utility model has two quantitative loops in the same injection valve. When one quantitative loop is being analyzed, the other quantitative loop is being injected. After the analysis is completed, the injection valve is switched once to switch the quantitative loop that has completed the injection to the analysis mode, and at the same time, the quantitative loop that has completed the analysis to the injection mode. This achieves the synchronous execution of injection and analysis, thereby improving the efficiency of analysis and detection.

[0023] (4) This utility model also has the functions of empty bottle detection of target sample bottle position and injection needle mis-puncture alarm, which effectively improves the fault tolerance of high performance liquid chromatograph and effectively reduces system abnormalities caused by human negligence or misoperation, thereby greatly improving the analysis efficiency. Attached Figure Description

[0024] Figure 1 This is a schematic diagram showing the injection of the first quantitative loop and the analysis of the second quantitative loop according to this utility model.

[0025] Figure 2 This is a schematic diagram showing the analysis of the first quantitative loop and the injection of the second quantitative loop according to this utility model.

[0026] Figure 3 This is a schematic diagram of the sample introduction component of this utility model.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1. Pump; 101. Outlet; 2. Tee; 21. First connector; 22. Second connector; 23. Third connector; 3. Injection valve; 31. First port; 32. Second port; 33. Third port; 34. Fourth port; 35. Fifth port; 36. Sixth port; 37. Seventh port; 38. Eighth port; 39. Ninth port; 310. Tenth port; 4. First quantitative loop; 5. Second quantitative loop; 6. Chromatographic column; 61. Liquid inlet 62. Outlet; 7. Detector; 71. Detection inlet; 72. Detection outlet; 8. Waste liquid box; 9. Sample injection assembly; 91. Motor; 92. Synchronous belt; 93. Indicator light; 94. Injection needle; 95. Probe rod; 96. Spring; 97. Baffle; 98. Fixing frame; 99. L-shaped plate; 910. Threaded rod; 911. Slider; 912. Clamping block; 913. Baffle; 914. U-shaped plate; 10. Sample introduction device; 11. Sample bottle. Detailed Implementation

[0029] The technical solution of this utility model will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are not all embodiments of this utility model. All other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model. It should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0030] like Figure 1 As shown, this utility model provides a multifunctional automatic sampler, including a pump 1, a three-way valve 2, an injection valve 3, a first quantitative loop 4, a second quantitative loop 5, a chromatographic column 6, a detector 7, a waste liquid box 8, an injection assembly 9, a sample introduction device 10, and a sample bottle 11. The pump 1 is connected to the three-way valve 2, the three-way valve 2 is connected to the injection valve 3, the injection valve 3 is also connected to the chromatographic column 6, the injection assembly 9, and the sample introduction device 10, respectively. The chromatographic column 6 is connected to the detector 7, the detector 7 is connected to the waste liquid box 8, and the sample bottle 11 is set corresponding to the injection assembly 9.

[0031] Pump 1 has an outlet 101. The tee fitting 2 has a first connection port 21, a second connection port 22, and a third connection port 23. The outlet 101 of pump 1 is connected to the first connection port 21 via a pipe. The injection valve 3 is a two-position ten-way injection valve, with a first port 31, a second port 32, a third port 33, a fourth port 34, a fifth port 35, a sixth port 36, a seventh port 37, an eighth port 38, a ninth port 39, and a tenth port 310. The second connection port 22 of the tee fitting 2 is connected to the eighth port 38 via a pipe, and the third connection port 23 of the tee fitting 2 is connected to the sixth port 36 via a pipe. The third port 33 and... The ninth interface 39 is connected through the first quantitative loop 4, and the first interface 31 and the fifth interface 35 are connected through the second quantitative loop 5; the chromatographic column 6 is provided with an inlet 61 and an outlet 62, the inlet 61 of the chromatographic column 6 is connected to the second interface 32 through a pipe, the detector 7 is provided with a detection inlet 71 and a detection outlet 72, the outlet 62 of the chromatographic column is connected to the detection inlet 71 of the detector 7 through a pipe, and the detection outlet 72 of the detector 7 is connected to the waste liquid box 8 through a pipe; the tenth interface 310 is connected to the sample introduction device 10 through a pipe, the fourth interface 34 is connected to the injection assembly 9 through a pipe; the seventh interface 37 is sealed with a plug.

[0032] The pipes connecting the second connector 22 and the eighth connector 38 of the tee fitting 2, and the pipes connecting the third connector 23 and the sixth connector 36 of the tee fitting 2, are set to be pipes of the same length.

[0033] Injection valve 3 Figure 1 When the connections shown are as follows, i.e., the first interface 31 is connected to the second interface 32, the third interface 33 is connected to the fourth interface 34, the fifth interface 35 is connected to the sixth interface 36, the seventh interface 37 is connected to the eighth interface 38, and the ninth interface 39 is connected to the tenth interface 310, one end of the first quantitative loop 4 is connected to the sample introduction device 10, and the other end of the first quantitative loop 4 is connected to the injection assembly 9. One end of the second quantitative loop 5 is connected to the outlet 101 of the pump 1, and the other end of the second quantitative loop 5 is connected to the inlet 61 of the chromatographic column 6. At this time, the first quantitative loop 4 is in the injection state, and the second quantitative loop 5 is in the analysis state. Figure 1After the state analysis shown is completed, control injection valve 3 to switch, which can be switched to Figure 2 The state shown is such that the first interface 31 is connected to the tenth interface 310, the second interface 32 is connected to the third interface 33, the fourth interface 34 is connected to the fifth interface 35, the sixth interface 36 is connected to the seventh interface 37, and the eighth interface 38 is connected to the ninth interface 39. At this time, one end of the first quantitative loop 4 is connected to the outlet 101 of the pump 1, and the other end of the first quantitative loop 4 is connected to the inlet 61 of the chromatographic column 6. One end of the second quantitative loop 5 is connected to the injection assembly 9, and the other end of the second quantitative loop 5 is connected to the sample introduction device 10. At this time, the first quantitative loop 4 is in the state of separation. The first quantitative loop 4 and the second quantitative loop 5 are in the injection state. By controlling the injection valve 3 to switch once, the first quantitative loop 4 and the second quantitative loop 5 can be switched between the injection and analysis states. The first quantitative loop 4, which was in the injection state in the previous state, enters the analysis state after the switch, and then the second quantitative loop 5 is converted to the injection state. Each switch has a quantitative loop that has already been injected, which can realize rapid injection. While one quantitative loop is being analyzed, the other quantitative loop is in the injection state, saving injection time and thus improving the working efficiency of the injector.

[0034] like Figure 3As shown in the figure, the sample injection assembly 9 includes a fixed bracket 98, a motor 91, a synchronous belt 92, an indicator light 93, a sample injection needle 94, a detection rod 95, a spring 96 and a retaining piece 97. The motor 91 is fixedly connected to the lower wall of the fixed bracket 98. The lower wall of the fixed bracket 98 is fixedly connected to an L-shaped plate 99. The L-shaped plate 99 includes a short part and a long part connected integrally. The short part is arranged parallel to the fixed bracket 98, and one end of the long part away from the short part is fixedly connected to the lower wall of the fixed bracket 98. A threaded rod 910 passes through the fixed bracket 98, and the threaded rod 910 is rotationally connected to the fixed bracket 98. The upper end of the threaded rod 910 extends out of the fixed bracket 98, and the lower end of the threaded rod 910 is rotationally connected to the short part. A slider 911 is sleeved outside the threaded rod 910, and the slider 911 is threadedly connected to the threaded rod 910. The slider 911 slides between the fixed bracket 98 and the short part. A limiting rod (not shown in the figure) also passes through the slider 911. The upper end of the limiting rod is fixedly connected to the fixed bracket 98, and the lower end of the limiting rod is fixedly connected to the short part. By providing the limiting rod, it is ensured that the slider 911 realizes vertical sliding during the rotation of the threaded rod 910. A clamping block 912 is fixedly connected to the side wall of the slider 911. The sample injection needle 94 passes through the clamping block 912, and the detection rod 95 passes through the clamping block 912. The upper end of the detection rod 95 is fixedly connected to the retaining piece 97. The retaining piece 97 is in a "ji" shape. The detection rod 95 is slidably connected relative to the clamping block 912. The retaining piece 97 extends out of the upper wall of the clamping block 912. The lower inner wall of the retaining piece 97 is fixedly connected to the spring 96, and the lower wall of the spring 96 is fixedly connected to the upper wall of the clamping block 912. A U-shaped plate 914 is fixedly connected to the upper wall of the clamping block 912. The indicator light 93 is fixedly connected to the side wall of the U-shaped plate 914. An opto-coupler switch is arranged on the inner side wall of the U-shaped plate 914. The opto-coupler switch is connected in series in the conduction circuit of the indicator light 93. The right vertical part of the retaining piece 97 extends into the U-shaped plate 914. The indicator light 93 is connected to the controller. A baffle 913 is integrally connected to the lower end of the detection rod 95. A through hole is provided on the baffle 913. The sample injection needle 94 is arranged corresponding to the through hole, and the sample injection needle 94 extends into the through hole. The sample bottle 11 is located below the sample injection assembly 9, and the mouth of the sample bottle 11 is arranged corresponding to the sample injection needle 94. The synchronous belt 92 is sleeved on the output end of the motor 91 and the upper end of the threaded rod 910 extending out of the fixed bracket 98. By starting the motor 91, the threaded rod 910 can be driven to rotate under the action of the synchronous belt 92.

[0035] When slider 911 is at the top of L-shaped plate 99, it is the initial state of injection needle 94. In this initial state, the lower end of injection needle 94 is located inside the perforation of baffle 913, and is flush with the lower end of baffle 913. When injection needle 94 is in its initial state, the distance between the lower end of baffle 913 and the mouth of sample vial 11 is a first set distance. Drive motor 91 rotates, causing slider 911 to move downwards a second set distance, slightly larger than the first set distance. When baffle 913 contacts the mouth of sample vial 11, probe rod 95 stops. As the slider 911 continues to move downwards, the clamping block 912 moves downwards relative to the baffle 97, causing the spring 96 to stretch. This allows the vertical part on the right side of the baffle 97 to slide out from inside the U-shaped plate, thus preventing it from blocking the optocoupler switch. When the optocoupler switch receives light, it becomes conductive, illuminating the indicator light 93, indicating the presence of a sample vial 11 below. If no sample vial is present, the baffle 813 will continue to move with the slider 911, and the baffle 97 will always block the optocoupler switch, keeping the indicator light 93 off. The presence or absence of the indicator light 93 is used to determine whether a sample vial 11 is placed below the sample injection assembly 9.

[0036] The controller is electrically connected to the motor 91. The controller receives the current signal from the motor 91. The controller has a maximum operating current value. When the motor 91 rotates, if the current value of the motor 91 received by the controller is always less than or equal to the maximum operating current value, it proves that the injection needle 94 has not been accidentally punctured. When the current value of the motor 91 received by the controller is greater than the maximum operating current value, it indicates that the injection needle 94 has been accidentally punctured.

[0037] This invention utilizes a single injection valve 3 and a single injection needle 94 to achieve rapid sample injection. Compared to the traditional dual injection valve 3 and dual injection needle 94, it not only saves costs but also achieves rapid sample injection, improves the sampler's processing speed, and reduces potential failure points. Each time the injection-analysis function is implemented, only the injection valve 3 needs to be switched once, compared to the conventional injection method which requires at least two switches. This extends the lifespan of the injection valve 3, potentially doubling it. Two quantitative loops are set within the same injection valve 3. While one quantitative loop is analyzing, the other is performing the injection operation. After the analysis is completed, a single switch of the injection valve 3 is performed, converting the completed quantitative loop to analysis mode and simultaneously converting the completed quantitative loop back to injection mode. This achieves synchronous injection and analysis, improving analytical detection efficiency.

[0038] This invention also features empty bottle detection at position 11 of the target sample vial and alarm function for accidental puncture of injection needle 94, effectively improving the fault tolerance of the high performance liquid chromatograph and reducing system abnormalities caused by human negligence or misoperation, thereby significantly improving analytical efficiency.

[0039] Finally, it should be noted that the above content is only used to illustrate the technical solution of this utility model, and is not intended to limit the scope of protection of this utility model. Simple modifications or equivalent substitutions made by those skilled in the art to the technical solution of this utility model do not depart from the essence and scope of the technical solution of this utility model.

Claims

1. A multifunctional automatic sampler, characterized in that, The system includes a pump, a three-way valve, an injection valve, a chromatographic column, a detector, an injection assembly, and a sample introduction device. The pump is connected to the three-way valve. The injection valve is connected to the three-way valve, the chromatographic column, the injection assembly, and the sample introduction device. The end of the chromatographic column away from the injection valve is connected to the detector. The injection valve is internally connected to a first quantitative loop and a second quantitative loop. Switch the injection valve to control the two ends of the first quantitative loop to be connected to the injection assembly and the sample introduction device, or to the pump and the chromatographic column, respectively; when the two ends of the first quantitative loop are connected to the injection assembly and the sample introduction device, the two ends of the second quantitative loop are connected to the pump and the chromatographic column, respectively; when the two ends of the first quantitative loop are connected to the pump and the chromatographic column, the two ends of the second quantitative loop are connected to the injection assembly and the sample introduction device, respectively.

2. The multifunctional automatic sampler according to claim 1, characterized in that, The injection valve is a two-position ten-way injection valve, which includes a first port, a second port, a third port, a fourth port, a fifth port, a sixth port, a seventh port, an eighth port, a ninth port, and a tenth port. The third port and the ninth port are connected to the first quantitative loop, the first port and the fifth port are connected to the second quantitative loop, the second port is connected to the chromatographic column, the fourth port is connected to the injection assembly, the sixth port and the eighth port are both connected to the three-way connector, the tenth port is connected to the sample introduction device, and the seventh port is sealed with a plug.

3. The multifunctional automatic sampler according to claim 2, characterized in that, The tee fitting has a first connection port, a second connection port and a third connection port. The first connection port is connected to the pump, the second connection port is connected to the eighth interface, and the third connection port is connected to the sixth interface.

4. A multifunctional automatic sampler according to claim 3, characterized in that, The pipes connecting the second connection port and the eighth interface, and the pipes connecting the third connection port and the sixth interface, are of the same length.

5. A multifunctional automatic sampler according to claim 1, characterized in that, The detector is connected to a waste liquid container at the end furthest from the chromatographic column.

6. A multifunctional automatic sampler according to claim 1, characterized in that, The injection assembly includes a motor, a fixed frame, an L-shaped plate, a threaded rod, a slider, and an injection needle. The motor and the L-shaped plate are fixedly connected to the fixed frame. The threaded rod is rotatably connected between the L-shaped plate and the fixed frame. The motor drives the threaded rod to rotate. The slider is threadedly connected to the threaded rod. When the threaded rod rotates, the slider moves along the vertical direction of the threaded rod. The injection needle is connected to the slider.

7. A multifunctional automatic sampler according to claim 6, characterized in that, A clamping block is fixedly connected to the slider, the injection needle is connected to the clamping block, a probe is inserted through the clamping block, the upper end of the probe passes through the clamping block and is connected to a baffle, and a spring is fixedly connected between the baffle and the clamping block.

8. A multifunctional automatic sampler according to claim 7, characterized in that, The lower end of the probe is fixedly connected to a baffle plate, and the baffle plate is provided with a through hole, into which the injection needle extends.

9. A multifunctional automatic sampler according to claim 8, characterized in that, A U-shaped plate is fixedly connected to the upper wall of the clamping block. An indicator light is provided on the side wall of the U-shaped plate. An optocoupler switch is provided inside the U-shaped plate. The optocoupler switch is connected in series with the conduction circuit of the indicator light. The baffle is used to block the optocoupler switch, thereby controlling whether the optocoupler switch is conducting. The indicator light is electrically connected to the controller.

10. A multifunctional automatic sampler according to claim 8, characterized in that, The upper end of the threaded rod passes through the fixed frame, and the output end of the motor also passes through the fixed frame. A timing belt is fitted onto the output end of the motor and the upper end of the threaded rod.

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