A high performance liquid chromatograph automatic sampling needle washing maintenance device

Abstract

The utility model provides a kind of high performance liquid chromatograph automatic sampling needle flushing maintenance device, it is related to high performance liquid chromatograph technical field, including flushing box, high pressure pump, several branch pipes of communication various solvents, main pipeline and controller, electromagnetic valve is provided on branch pipe, main pipeline is connected high pressure pump, high pressure pump and flushing box one side surface are connected by connecting port intercommunication, connecting port intercommunication sampling needle fixing mechanism, including clamping head and knob cover, clamping head is through, and outer circumferential surface is equipped with outer thread, and is connected with the inside thread of knob cover, the equal angle of several slotted of clamping head port circumference is equipped, and port is equipped with bevel, corresponding knob cover inside is equipped with with bevel corresponding inclined hole, the utility model, effectively avoid sampling needle blockage: by using different solvents to carry out high pressure reverse phase pressurization flushing, can thoroughly remove the blockage in sampling needle, greatly reduce the probability of sampling needle blockage, guarantee the normal operation of high performance liquid chromatograph.

Description

Technical Field

[0001] This utility model relates to the field of high performance liquid chromatography (HPLC) technology, specifically to an automatic injection needle flushing and maintenance device for HPLC, used for reverse-phase pressure flushing and maintenance of the injection needle of the HPLC autosampler. Background Technology

[0002] High-performance liquid chromatography (HPLC) is an analytical instrument widely used in chemistry, biology, medicine, and other fields. The autosampler, as one of its key components, improves analytical efficiency and accuracy. The inner diameter of the autosampler needle is typically small, generally 0.1-0.2 mm. During use, the needle often becomes clogged due to impurities, particulate matter, or adsorption of the sample onto the inner wall of the needle.

[0003] Currently, when an autosampler needle becomes clogged, the first step is usually to use the autosampler's built-in cleaning function. However, while this method may be effective when the clogging is not severe, its effectiveness gradually decreases with each injection. When the autosampler's cleaning function fails to resolve the clogging, the needle needs to be removed and ultrasonically treated with an organic solvent. Even after ultrasonic treatment, some stubborn clogging cases may not be completely resolved. Ultimately, the needle must be replaced, and since needles are typically expensive, this significantly increases the instrument's operating costs.

[0004] Therefore, it is necessary to design a flushing and maintenance device that can effectively solve the problem of needle clogging, remove sample residue, extend the service life of the needle, and reduce the operating cost of the instrument. Utility Model Content

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide an automatic syringe flushing and maintenance device and method for high-performance liquid chromatographs. By utilizing the high-pressure pump of the high-performance liquid chromatograph, different solvents are used to periodically perform high-pressure flushing and maintenance on the syringe, effectively preventing syringe blockage, removing sample residue from the syringe, extending the syringe's service life, and reducing instrument operating costs.

[0006] To achieve the above objectives, this utility model provides the following technical solution: An automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph (HPLC): comprising a flushing chamber, a high-pressure pump, several branch pipes, a main pipe, and a controller. One end of each branch pipe is connected to a solvent, and a solenoid valve is installed on the branch pipe. The other end is connected to the main pipe, which is connected to the high-pressure pump. The high-pressure pump is connected to one side of the flushing chamber via a connection port. An injection needle fixing mechanism is provided inside the connection port. The injection needle fixing mechanism is used to fix the injection needle. The injection needle fixing mechanism includes a clamping head and a knob sleeve. The clamping head is located on the connection port and has a through-hole. An external thread is formed on the outer circumferential surface of the clamping head, which is threaded to the inner side of the knob sleeve. Several slots are formed at equal angles on the circumference of the clamping head port, and a bevel is formed on the port. A corresponding beveled hole is provided on the inner side of the knob sleeve.

[0007] Preferably, a support plate is also fixed to the side of the rinsing box, and a connecting plate is provided at the outer end of the support plate. Another injection needle fixing mechanism is provided on the connecting plate, which consists of a clamping head and a knob sleeve. The clamping head is fixedly mounted on the support plate and allows the injection needle to pass through. The centers of the two sets of injection needle fixing mechanisms are located on the same horizontal line.

[0008] Preferably, the support plate has a sliding groove, and the corresponding connecting plate has a slider. The slider is slidably connected in the sliding groove. Fixing plates are provided on both sides of the slider. The fixing plates have threaded holes, and threaded bolts are engaged in the threaded holes for fixing the support plate.

[0009] Preferably, a U-shaped baffle is slidably provided on the upper surface of the rinsing tank.

[0010] Preferably, a lifting plate is provided on one side of the U-shaped baffle, and a mounting plate is provided on the washing box. An electric telescopic component is installed on the mounting plate, and the telescopic rod of the electric telescopic component is connected to the lifting plate to drive the U-shaped baffle to rise and fall.

[0011] Preferably, the connection port is provided with a star-shaped opening sealing mold.

[0012] Preferably, the bottom of the rinsing tank is also provided with a drain port.

[0013] This invention provides an automatic syringe flushing and maintenance device for high-performance liquid chromatographs. It has the following beneficial effects: 1. This automatic syringe flushing and maintenance device for high performance liquid chromatographs effectively prevents syringe clogging: by using different solvents for high-pressure reverse-phase flushing, it can thoroughly remove blockages from the syringe, greatly reducing the probability of syringe clogging and ensuring the normal operation of the high performance liquid chromatograph.

[0014] 2. This high-performance liquid chromatograph automatic injection needle flushing and maintenance device and injection needle fixing mechanism effectively clamp the injection needle, ensuring that the solvent can smoothly flush the injection needle. Specifically, the injection needle fixing mechanism includes a clamping head and a knob sleeve. The clamping head is located on the connection port and is internally continuous. The outer circumferential surface of the clamping head has external threads that connect with the inner thread of the knob sleeve. The circumference of the clamping head port has several slots at equal angles, and the port has a bevel. The inner side of the knob sleeve has a beveled hole corresponding to the bevel. The rotation of the knob sleeve is converted into the vertical movement of the clamping head, effectively clamping the injection needle.

[0015] 3. The automatic syringe flushing and maintenance device for this high performance liquid chromatograph is equipped with two syringe fixing mechanisms, which enhances the clamping effect and stability of the syringe. The outer syringe fixing mechanism can slide, thereby adjusting the distance between the two syringe fixing mechanisms to accommodate syringes of different lengths, making it more versatile.

[0016] 4. The automatic injection needle flushing and maintenance device for this high performance liquid chromatograph is equipped with a sliding U-shaped baffle, which effectively blocks the solvent passing through the injection needle to prevent leakage. A drain port is set at the bottom of the flushing chamber for easy drainage. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of an automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph (unused state). Figure 2 This is a schematic diagram of the U-shaped baffle in the lifting and lowering state of an automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to the present invention; Figure 3 This is a cross-sectional view (in use) of an automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to the present invention. Figure 4 for Figure 3 Schematic diagram at point A; Figure 5 This is a schematic diagram of the injection needle fixing mechanism of an automatic injection needle flushing and maintenance device for high performance liquid chromatographs according to this utility model.

[0018] In the diagram: 1. Flushing chamber; 2. High-pressure pump; 3. Branch pipeline; 4. Main pipeline; 5. Solenoid valve; 6. Injection needle; 71. Clamping head; 72. Knob sleeve; 73. Groove; 74. Bevel; 75. Angled hole; 8. Support plate; 9. Connecting plate; 61. Slide groove; 10. Sliding block; 11. Fixing plate; 12. U-shaped baffle; 13. Lifting plate; 14. Electric telescopic component; 15. Star-shaped opening sealing mold; 16. Drain port; 17. Mounting plate. Detailed Implementation

[0019] This utility model provides a flushing and maintenance device for the automatic injection needle 6 of a high-performance liquid chromatograph, such as... Figure 1-5 As shown, the system includes a rinsing chamber 1, a high-pressure pump 2, several branch pipes 3, a main pipe 4, and a controller. One end of each branch pipe 3 is connected to a solvent for transporting different types of solvents (such as methanol, acetonitrile, water, etc.). A solenoid valve 5 is installed on each branch pipe 3 and is connected to the controller circuit. The other end of the branch pipe 3 is connected to the main pipe 4, which is connected to the high-pressure pump 2. The high-pressure pump 2 is connected to one side of the rinsing chamber 1 through a connection port. A needle fixing mechanism is installed inside the connection port to fix the needle 6. The needle fixing interface assembly is designed with an adjustable fixing structure to accommodate various sizes of needles 6, as the inner and outer diameters of needles 6 vary from manufacturer to manufacturer. Specifically, in this technical solution, the injection needle 6 fixing mechanism includes a clamping head 71 and a knob sleeve 72. The clamping head 71 is set on the connection port, and the clamping head 71 is internally connected. The outer circumferential surface of the clamping head 71 is provided with external threads, which are threaded to the inner side of the knob sleeve 72. Several slots 73 are provided at equal angles on the circumference of the clamping head 71 port, and the port is provided with a bevel 74. The inner side of the corresponding knob sleeve 72 is provided with a beveled hole 75 corresponding to the bevel 74.

[0020] like Figure 1 and 2 As shown, a support plate 8 is also fixed on the side of the rinsing box 1. A connecting plate 9 is provided at the outer end of the support plate 8. Another injection needle 6 fixing mechanism is provided on the connecting plate 9, which consists of a clamping head 71 and a knob sleeve 72. The clamping head 71 is fixed on the support plate 8 and allows the injection needle 6 to pass through. The centers of the two sets of injection needle 6 fixing mechanisms are located on the same horizontal line.

[0021] In the above technical solution, the support plate 8 is provided with a sliding groove 61, and the corresponding connecting plate 9 is provided with a slider 10. The slider 10 is slidably connected in the sliding groove 61. Fixing plates 11 are provided on both sides of the slider 10. The fixing plates 11 are provided with threaded holes, and threaded bolts are engaged in the threaded holes for fixing the support plate 8.

[0022] like Figure 1 and Figure 2 As shown, a U-shaped baffle 12 is slidably installed on the upper surface of the rinsing tank 1.

[0023] like Figure 2 As shown, a lifting plate 13 is provided on one side of the U-shaped baffle 12, and a mounting plate 17 is provided on the washing box 1. An electric telescopic component 14 is installed on the mounting plate 17. The telescopic rod of the electric telescopic component 14 is connected to the lifting plate 13, which drives the U-shaped baffle 12 to rise and fall. The electric telescopic component 14 is connected to the controller circuit.

[0024] like Figure 4As shown, a star-shaped opening sealing mold 15 is provided inside the connection port to further enhance the sealing performance.

[0025] In other embodiments of this case, the controller, solenoid valve, and electric telescopic component are all existing technologies, and their models and specifications are selected according to actual needs.

[0026] Working principle: When using the automatic injection needle 6 flushing and maintenance device for high performance liquid chromatographs, the steps are as follows: Equipment installation and preparation The high-pressure pump 2 of the flushing and maintenance device of this utility model is reliably connected to the connection port on the side of the flushing box 1. An appropriate amount of sealant can be applied to the connection to ensure a good seal. According to the specifications of the injection needle 6 to be rinsed, adjust the distance between the two injection needle 6 fixing interface components. Specifically, loosen the bolts so that the slider 10 can drive the connecting plate 9 to slide in the slide groove 61. After adjusting the position, tighten the bolts to fix the connecting plate 9.

[0027] Methanol, acetonitrile, and water are added to solvent storage containers (not shown in the figure), and the battery valves on the corresponding branch pipes 3 are opened and closed by the controller to adjust the initially selected solvent channel to the methanol channel.

[0028] Installation of injection needle 6 Remove the slightly clogged injection needle 6 from the HPLC autosampler and carefully insert it into the two needle 6 retaining mechanisms, ensuring the tip of the injection needle 6 is connected to the connector. Figure 4 As shown, the front end of the injection needle 6 passes through the star-shaped opening sealing mold 15, and then the knob sleeve 72 is turned so that the knob sleeve 72 is pressed on the inclined surface 74 of the clamping sleeve in the inclined hole 75, thereby pressing and clamping the injection needle 6 to ensure that the connection between the injection needle 6 and the fixed interface assembly is tight and there is no looseness. The controller controls the electric telescopic component 14 to raise the U-shaped baffle 12 and block the outer port of the feed needle; High-pressure flushing The high-pressure pump 2 is started, and the flushing pressure is set to 10 MPa for the high-performance liquid chromatograph's automatic injection needle 6 flushing and maintenance device, with a flushing time of 5 minutes. High-pressure pump 2 draws methanol from the solvent storage container, which then flows through branch line 3, main line 4, high-pressure pump 2, and the connection port into the injection needle 6 for high-pressure flushing. During the flushing process, the methanol liquid flowing from the other end of the injection needle 6 gradually becomes clear, indicating that the blockage is being gradually cleared.

[0029] Replace solvent and rinse Five minutes later, turn off high-pressure pump 2 and switch the solvent channel to the acetonitrile channel via the control valve. Restart high-pressure pump 2, set the flushing pressure to 12 MPa, and the flushing time to 3 minutes, using acetonitrile to further flush the injection needle 6.

[0030] Three minutes later, the high-pressure pump 2 was turned off again. The solvent channel was switched to the water channel through the control valve. The flushing pressure was set to 8 MPa and the flushing time was 2 minutes. The injection needle 6 was flushed with water for the last time to remove residual organic solvents.

[0031] Complete rinsing After rinsing, the high-pressure pump 2 is shut off via the controller, the U-shaped baffle 12 is lowered, and the injection needle 6 is removed from the injection needle 6 fixing mechanism. The injection needle 6 is then purged and dried with clean nitrogen gas before being reinstalled onto the autosampler. Subsequent experimental verification showed that the clogging problem of the injection needle 6 was completely resolved, and the accuracy and repeatability of the analytical results met the requirements.

[0032] In summary, the automatic injection needle 6 rinsing and maintenance device for high performance liquid chromatographs of this invention has significant advantages and good application prospects. It can effectively solve the problems existing in the prior art and provide strong support for the normal operation of high performance liquid chromatographs and the accuracy of analysis results.

[0033] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An automatic syringe flushing and maintenance device for high-performance liquid chromatographs, characterized in that: The system includes a rinsing chamber (1), a high-pressure pump (2), several branch pipes (3), a main pipe (4), and a controller. One end of each branch pipe (3) is connected to a solvent, and a solenoid valve (5) is installed on the branch pipe (3). The other end is connected to the main pipe (4), which is connected to the high-pressure pump (2). The high-pressure pump (2) is connected to one side of the rinsing chamber (1) through a connection port. A needle fixing mechanism is installed inside the connection port. The needle fixing mechanism is used for... The injection needle (6) is fixed. The injection needle fixing mechanism includes a clamping head (71) and a knob sleeve (72). The clamping head (71) is set on the connection port. The clamping head (71) is internally connected and has an external thread on its outer circumferential surface. It is threaded to the inner side of the knob sleeve (72). The clamping head (71) has several slots (73) at equal angles on its port circumference and a bevel (74) on its port. The knob sleeve (72) has a corresponding bevel hole (75) on its inner side that corresponds to the bevel (74).

2. The automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to claim 1, characterized in that: The side of the rinsing box (1) is also fixed with a support plate (8). The outer end of the support plate (8) is provided with a connecting plate (9). Another injection needle fixing mechanism is provided on the connecting plate (9), which is a clamping head (71) and a knob sleeve (72). The clamping head (71) is fixed on the support plate (8) and allows the injection needle (6) to pass through. The centers of the two sets of injection needle fixing mechanisms are located on the same horizontal line.

3. The automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to claim 2, characterized in that: The support plate (8) has a groove (61) and the corresponding connecting plate (9) has a slider (10). The slider (10) is slidably connected in the groove (61). The slider (10) has a fixing plate (11) on both sides. The fixing plate (11) has a threaded hole and a threaded bolt is engaged in the threaded hole to fix the support plate (8).

4. The automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to claim 1, characterized in that: A U-shaped baffle (12) is slidably provided on the upper surface of the rinsing box (1).

5. The automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to claim 4, characterized in that: A lifting plate (13) is provided on one side of the U-shaped baffle (12), and a mounting plate (17) is provided on the flushing box (1). An electric telescopic component (14) is installed on the mounting plate (17), and the telescopic rod of the electric telescopic component (14) is connected to the lifting plate (13) to drive the U-shaped baffle (12) to rise and fall.

6. The automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to claim 1, characterized in that: The connection port is provided with a star-shaped opening sealing mold (15).

7. The automatic injection needle flushing and maintenance device for a high-performance liquid chromatograph according to claim 1, characterized in that: The bottom of the rinsing box (1) is also provided with a drain port (16).

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