High-pressure infusion pump for high performance liquid chromatography system

Abstract

The utility model discloses a high-pressure infusion pump for a high performance liquid chromatography system, which comprises a driving module and a pump module, the driving module comprises a stepping motor and a driving shell, a transmission cavity is arranged in the driving shell, the output end of the stepping motor is connected with an eccentric shaft, the eccentric shaft is provided with a photometric sheet, the driving shell is provided with a photoelectric sensor, and the photoelectric sensor is connected with the transmission cavity. The pump module comprises a pump body and a pump head, a linear bearing is arranged in the pump body in a penetrating mode, a push rod is correspondingly inserted in the linear bearing, one end of the push rod is correspondingly in transmission connection with the eccentric shaft, and the other end of the push rod is connected with a plunger seat. A butt joint groove is formed in the side, close to the pump module, of the driving shell, and the groove wall of the butt joint groove is gradually reduced from an opening of the butt joint groove to the groove bottom end of the butt joint groove in the axial direction of the butt joint groove so that a step structure can be formed. The method has the effect of remarkably improving the output stability of the mobile phase.

Description

Technical Field

[0001] This utility model relates to the field of mechanical equipment technology, and in particular to a high-pressure delivery pump for a high-performance liquid chromatography system. Background Technology

[0002] High-pressure pumps are key components in high-performance liquid chromatography (HPLC) technology. They provide a stable and continuous mobile phase to ensure that the sample enters the chromatographic column uniformly and is separated efficiently. They can output high-pressure mobile phase to overcome the resistance of the chromatographic column packing and achieve flow rate repeatability to ensure the repeatability and accuracy of analytical results. However, existing high-pressure pumps have problems such as poor sealing, complex structure and unstable speed, resulting in high maintenance costs, high cost and inaccurate analytical results.

[0003] Therefore, there is an urgent need to develop a high-pressure delivery pump for high-performance liquid chromatography systems to solve the technical problems encountered in the existing technology. Utility Model Content

[0004] To address the aforementioned technical problems, the purpose of this utility model is to provide a high-pressure delivery pump for high-performance liquid chromatography systems, which can solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides a high-pressure delivery pump for a high-performance liquid chromatography system, comprising:

[0006] A drive module includes a stepper motor and a drive housing. The drive housing has a transmission cavity and a drive hole, a detection hole, and an output hole. The drive hole, the detection hole, and the output hole are all connected to the transmission cavity. The output end of the stepper motor is inserted into the transmission cavity along the drive hole and connected to an eccentric shaft. A photometer is provided on the side of the eccentric shaft away from the stepper motor, extending out of the drive housing along the detection hole. A photoelectric sensor is provided on the side of the drive housing corresponding to the detection hole, and the photoelectric sensor is positioned facing the photometer.

[0007] A pump module includes a pump body and a pump head. One end of the pump body is connected to the drive housing, and the other end of the pump body is connected to the pump head. A one-way valve is installed on the pump head. A linear bearing is installed through the pump body, and a push rod is inserted into the linear bearing. One end of the push rod is connected to the eccentric shaft via a transmission bearing. A first elastic element is sleeved on the end of the push rod near the eccentric shaft. The other end of the push rod is connected to a plunger seat. A plunger rod is installed on the plunger seat at the end away from the push rod. A one-way valve is installed on the pump head, and a flow channel communicating with the one-way valve is opened in the pump head. The plunger rod extends into the flow channel.

[0008] A docking groove is provided on the side of the drive housing near the pump module. The groove wall gradually decreases in size along its axial direction from the opening of the groove to the bottom of the groove to form a stepped structure. A docking part is provided on the side of the pump body facing the drive housing. The docking part is adapted and snapped into the stepped structure.

[0009] In some embodiments, a first bearing and a second bearing are respectively provided in the driving hole and the detection hole, the first bearing and the second bearing are both sleeved on the eccentric shaft, and a wave spring is provided between the second bearing and the eccentric shaft.

[0010] In some embodiments, the high-pressure pump for a high-performance liquid chromatography system provided by this invention further includes:

[0011] A cleaning block is disposed on the pump body at one end corresponding to the pump head, and a diaphragm is disposed between the cleaning block and the pump body.

[0012] In some embodiments, a buffer pad is provided between the stepper motor and the drive housing.

[0013] In some embodiments, a first seal is provided at the connection between the pump head and the pump body.

[0014] In some embodiments, the light-shielding sheet has a notch;

[0015] The rotation path of the light-shielding plate coincides with the sensing position of the photoelectric sensor.

[0016] In some embodiments, the pump body is provided with a waste liquid outlet for discharging leaked liquid.

[0017] Compared with the prior art, the high-pressure pump for high-performance liquid chromatography systems provided by this invention has the following advantages:

[0018] 1. The high-pressure pump for high-performance liquid chromatography system provided by this utility model integrates a photoelectric sensor below the eccentric shaft and connects it to the corresponding control system, realizing high-precision real-time monitoring and dynamic control of motor speed, which significantly improves the stability of mobile phase output, system energy efficiency ratio and environmental adaptability. This non-contact detection has efficient rapid response and intelligent expansion capabilities, effectively solving the problems of lag and reliability of traditional mechanical systems.

[0019] 2. The high-pressure pump for high-performance liquid chromatography system provided by this utility model achieves precise axial and radial positioning through the snap-fit ​​design of the stepped docking groove and the pump body docking part and the multi-stage stepped structure, which effectively improves the accuracy and stability of the docking between the pump body and the drive housing, and also effectively improves the convenience of assembly docking, thereby effectively improving production efficiency. In addition, it forms multiple dynamic sealing layers, thereby enhancing the sealing reliability.

[0020] 3. The high-pressure infusion pump for high-performance liquid chromatography systems provided by this utility model adds a wave spring between the eccentric shaft and the mounting bearing. The elastic characteristics of the wave spring can actively absorb axial or radial position errors caused by bearing installation deviations, assembly tolerances or thermal expansion, thereby achieving dynamic position deviation compensation, significantly improving the reliability of the transmission system and further extending the service life of the high-pressure infusion pump. Attached Figure Description

[0021] The preferred embodiments will be described below in a clear and easy-to-understand manner, in conjunction with the accompanying drawings, to further explain the above-mentioned characteristics, technical features, advantages and implementation methods of this utility model.

[0022] Figure 1 This is a three-dimensional schematic diagram of a high-pressure infusion pump for a high-performance liquid chromatography system according to a preferred embodiment of the present invention.

[0023] Figure 2 This is a cross-sectional structural schematic diagram of a high-pressure infusion pump for a high-performance liquid chromatography system according to a preferred embodiment of the present invention.

[0024] Explanation of icon numbers:

[0025] 10 Stepper motor, 20 Drive housing, 21 Eccentric shaft, 22 Optical plate, 23 Photoelectric sensor, 24 First bearing, 25 Second bearing, 26 Buffer pad, 27 Transmission cavity, 28 Wave spring, 30 Pump body, 31 Linear bearing, 32 Push rod, 33 Piston seat, 34 Piston rod, 35 Cleaning block, 36 First elastic element, 40 Pump head, 50 One-way valve, 51 Flow channel, 52 First seal. Detailed Implementation

[0026] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the specific implementation methods of this utility model will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of this utility model. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0027] To keep the drawings concise, each figure only schematically shows the parts relevant to the utility model, and these do not represent the actual structure of the product. Furthermore, for ease of understanding, in some figures, only one of the components with the same structure or function is schematically depicted, or only one is labeled. In this document, "one" not only means "only one," but can also mean "more than one."

[0028] It should also be further understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0029] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0030] Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] In one embodiment, refer to the appendix to the specification. Figure 1 and 2This utility model provides a high-pressure infusion pump for a high-performance liquid chromatography (HPLC) system, comprising a drive module and a pump module. The drive module includes a stepper motor 10 and a drive housing 20. The drive housing 20 has a transmission cavity 27 and a drive hole, a detection hole, and an output hole, all communicating with the transmission cavity 27. The output end of the stepper motor 10 is inserted into the transmission cavity 27 along the drive hole and connected to an eccentric shaft 21. A photometer 22 extends from the drive housing 20 along the detection hole on the side of the eccentric shaft 21 away from the stepper motor 10. A photoelectric sensor 23 is disposed on the side of the drive housing 20 corresponding to the detection hole, facing the photometer 22. The pump module includes a pump body 30 and a pump head 40. One end of the pump body 30 is connected to the drive housing 20, and the other end is connected to the pump head 40. A one-way valve 50 is installed on the pump body 30. A linear bearing 31 is installed through the pump body 30. A push rod 32 is inserted into the linear bearing 31. One end of the push rod 32 is connected to the eccentric shaft 21 through a transmission bearing. A first elastic element 36 is sleeved on the end of the push rod 32 that is close to the eccentric shaft 21. The other end of the push rod 32 is connected to a plunger seat 33. A plunger rod 34 is provided on the end of the plunger seat 33 that is away from the push rod 32. A one-way valve 50 is installed on the pump head 40. A flow channel 51 communicating with the one-way valve 50 is opened in the pump head 40. The plunger rod 34 extends into the flow channel 51. A docking groove is opened on the side of the drive housing 20 that is close to the pump module. The groove wall gradually decreases from the opening of the groove to the bottom of the groove along its axial direction to form a stepped structure. A docking part is provided on the side of the pump body 30 facing the drive housing 20. The docking part is adapted to and snapped into the stepped structure.

[0032] Specifically, a bracket is provided on the pump body 30 to ensure stable placement on the work platform. The stepper motor 10 is inserted into the transmission cavity 27 within the drive housing 20 through a drive hole. The output end of the stepper motor 10 is connected to an eccentric shaft 21, which has a connection hole. A transmission bearing is installed on the eccentric shaft 21 at the height corresponding to the output hole. The output end of the stepper motor 10 is inserted into and fixed in the connection hole with fastening screws to achieve a stable connection between the stepper motor 10 and the eccentric shaft 21. This allows the eccentric shaft 21 to rotate with high precision following the rotation of the stepper motor 10. The drive housing 20 extends from the other end of the eccentric shaft 21 and is equipped with a photometer 22, which is secured by screws. A photoelectric sensor 23 is fixed to the end face of the eccentric shaft 21 and is fixed to the side of the corresponding detection hole on the drive housing 20 by screws. The photometer 22 and the photoelectric sensor 23 are optically aligned. The rotation of the photometer 22 triggers the photoelectric sensor 23 to monitor the rotational position of the eccentric shaft 21 in real time. A push inner hole is opened on the linear bearing 31. One end of the push rod 32 in the pump module passes through the push inner hole and is connected to the transmission bearing on the eccentric shaft 21. The other end of the push rod 32 is fixed to the plunger seat 33 by screws. A first elastic element 36 is sleeved on the push rod 32. The first elastic element 36 is preferably a helical spring. The plunger rod 33 is reset by the reset action of the first elastic element 36. 4. After the pump moves out, it can automatically reset, thus ensuring the stable operation of the entire pump. A plunger rod 34 is placed on the side of the plunger seat 33 away from the push rod 32. The pump head 40 integrates a one-way valve 50 and a flow channel 51, which, together with the plunger rod 34 extending into the flow channel 51, forms a movable cavity. Under the periodic rotation of the eccentric shaft 21, the plunger rod 34 can reciprocate along the axial direction of the push rod 32 through the transmission action of the push rod 32 and the plunger seat 33. This causes the volume of the plunger rod 34 in the flow channel 51 to change repeatedly, thereby changing the volume of the movable cavity. This achieves the technical effect of controlling the suction and discharge of liquid and stabilizing the flow rate. There are two one-way valves 50. One-way valves 50 are respectively located on both sides of the pump head 40 and are connected to the flow channel 51. When the plunger rod 34 moves backward, the volume of the movable cavity increases, the upper one-way valve 50 closes, and the lower one-way valve 50 opens, drawing in liquid. When the plunger rod 34 moves forward, the volume of the movable cavity is compressed, the lower one-way valve 50 closes, and the upper one-way valve 50 opens, pumping out liquid. This process is repeated cyclically. By adjusting the speed of the stepper motor 10, a controllable, continuous, and stable flow phase output can be achieved. In addition, the groove wall of the docking groove on the drive housing 20 has a gradually narrowing step structure from the opening to the bottom of the groove, which engages with the docking part of the pump body 30 to achieve a synchronous radial and axial sealing combination, effectively improving the sealing reliability of the overall connection structure and providing convenience for installation and disassembly.

[0033] In one embodiment, refer to the appendix to the specification. Figure 1 and 2 Based on the above embodiment, a first bearing 24 and a second bearing 25 are respectively provided in the driving hole and the detection hole. The first bearing 24 and the second bearing 25 are both sleeved on the eccentric shaft 21, and a wave spring 28 is provided between the second bearing 25 and the eccentric shaft 21.

[0034] Specifically, the first bearing 24 is mainly installed in the drive hole and is adapted to the drive hole to bear the radial load of the eccentric shaft 21, so as to effectively reduce the frictional resistance at the connection between the output shaft of the stepper motor 10 and the eccentric shaft 21. The second bearing 25 is mainly installed in the detection hole to bear the combined radial and axial loads of the eccentric shaft 21 to ensure the stable rotation of the photometer 22. The wave spring 28 is set between the second bearing 25 and the eccentric shaft 21. It automatically adjusts the bearing clearance through its own elastic deformation to compensate for the position deviation of the drive bearing. In addition, by absorbing the axial vibration generated when the eccentric shaft 21 rotates, it effectively prevents the photometer 22 from being falsely triggered by the photoelectric sensor 23 due to vibration, thereby ensuring the accuracy of detection. Both the first bearing 24 and the second bearing 25 can be ball bearings.

[0035] In one embodiment, refer to the appendix to the specification. Figure 2 The high-pressure pump for high-performance liquid chromatography system provided by this utility model also includes a cleaning block 35, which is disposed on the pump body 30 at one end close to the pump head 40, and a diaphragm is provided between the cleaning block 35 and the pump body 30.

[0036] Specifically, there is one cleaning block 35, and each cleaning block 35 is equipped with a cleaning pipe connector to connect to an external cleaning pipe. The cleaning block 35 is installed at the end of the pump body 30 near the pump head 40, and the cleaning fluid is delivered into the pump head 40 through the built-in spray hole to clean the residual samples or contaminants inside the pump body 30. The diaphragm is mainly sandwiched between the cleaning block 35 and the pump body 30 to form a sealing structure, which effectively prevents leakage during pump operation and effectively improves the sealing reliability of the pump.

[0037] In one embodiment, refer to the appendix to the specification. Figure 2 Based on the above embodiments, a buffer pad 26 is provided between the stepper motor 10 and the drive housing 20.

[0038] Specifically, the buffer pad 26 is disposed between the contact surface of the stepper motor 10 base and the drive housing 20 to form a buffer support, thereby forming vibration isolation and absorbing the impact energy of the stepper motor 10, thus achieving the technical effect of protecting the motor and the entire system and effectively improving the service life of the overall device.

[0039] In one embodiment, refer to the appendix to the specification. Figure 2 A first seal 52 is provided at the connection between the pump head 40 and the pump body 30.

[0040] Specifically, the first sealing element 52 is disposed between the contact surfaces of the pump head 40 connecting flange and the pump body 30 connecting flange to further improve the sealing performance of the connection between the pump head 40 and the pump body 30, thereby ensuring that the moving cavity is an independent sealed cavity, thus ensuring the stability of the flow rate, and also effectively preventing liquid leakage, thereby effectively improving the reliability of the overall device.

[0041] In one embodiment, based on the above embodiment, a notch is provided on the light-shielding sheet, and the rotation path of the light-shielding sheet coincides with the sensing position of the photoelectric sensor 23.

[0042] Specifically, the transmitting and receiving ends of the photoelectric sensor 23 are located on both sides of the sensing position and the rotation axis of the light-shielding plate, forming an optical path. The notch on the light-shielding plate matches the photoelectric sensor 23. When the light-shielding plate rotates, the optical path is briefly opened when the notch passes the sensing position of the photoelectric sensor 23, triggering a pulse signal. When the non-notch area blocks the optical path, the sensor outputs another signal. By transmitting the two signals to the control terminal, the rotation status of the eccentric shaft 21 is obtained through analysis by the control terminal, realizing high-precision real-time monitoring and dynamic control of the motor speed.

[0043] In one embodiment, based on the above embodiment, the pump body 30 is provided with a waste liquid port, which is used to discharge leaked liquid.

[0044] Specifically, the waste liquid outlet is located on the pump body 30 and is connected to the transmission inner hole inside the pump body 30 to ensure that the leaked liquid can be discharged in a timely and proactive manner in the event of a leak, thereby effectively preventing the leaked liquid from corroding the back-end drive module. This not only improves the reliability of equipment operation but also extends the service life of the back-end drive module.

[0045] It should be noted that the above embodiments can be freely combined as needed. The above are merely preferred embodiments of this utility model. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this utility model, and these improvements and modifications should also be considered within the protection scope of this utility model.

Claims

1. A high-pressure delivery pump for a high-performance liquid chromatography system, characterized in that, include: A drive module includes a stepper motor and a drive housing. The drive housing has a transmission cavity and a drive hole, a detection hole, and an output hole. The drive hole, the detection hole, and the output hole are all connected to the transmission cavity. The output end of the stepper motor is inserted into the transmission cavity along the drive hole and connected to an eccentric shaft. A photometer is provided on the side of the eccentric shaft away from the stepper motor, extending out of the drive housing along the detection hole. A photoelectric sensor is provided on the side of the drive housing corresponding to the detection hole, and the photoelectric sensor is positioned facing the photometer. A pump module includes a pump body and a pump head. One end of the pump body is connected to the drive housing, and the other end of the pump body is connected to the pump head. A one-way valve is installed on the pump head. A linear bearing is installed through the pump body, and a push rod is inserted into the linear bearing. One end of the push rod is connected to the eccentric shaft via a transmission bearing. A first elastic element is sleeved on the end of the push rod near the eccentric shaft. The other end of the push rod is connected to a plunger seat. A plunger rod is installed on the plunger seat at the end away from the push rod. A one-way valve is installed on the pump head, and a flow channel communicating with the one-way valve is opened in the pump head. The plunger rod extends into the flow channel. A docking groove is provided on the side of the drive housing near the pump module. The groove wall gradually decreases in size along its axial direction from the opening of the groove to the bottom of the groove to form a stepped structure. A docking part is provided on the side of the pump body facing the drive housing. The docking part is adapted and snapped into the stepped structure.

2. The high-pressure delivery pump for a high-performance liquid chromatography system according to claim 1, characterized in that, A first bearing and a second bearing are respectively provided in the driving hole and the detection hole. Both the first bearing and the second bearing are sleeved on the eccentric shaft. A wave spring is provided between the second bearing and the eccentric shaft.

3. The high-pressure delivery pump for a high-performance liquid chromatography system according to claim 2, characterized in that, Also includes: A cleaning block is disposed on the pump body at one end corresponding to the pump head, and a diaphragm is disposed between the cleaning block and the pump body.

4. The high-pressure delivery pump for a high-performance liquid chromatography system according to claim 3, characterized in that, A buffer pad is provided between the stepper motor and the drive housing.

5. The high-pressure pump for a high-performance liquid chromatography system according to any one of claims 1-4, characterized in that, A first seal is provided at the connection between the pump head and the pump body.

6. The high-pressure pump for a high-performance liquid chromatography system according to claim 5, characterized in that, The photometer has a notch; The rotation path of the photometer coincides with the sensing position of the photoelectric sensor.

7. The high-pressure pump for a high-performance liquid chromatography system according to claim 6, characterized in that, The pump body is provided with a waste liquid outlet, which is used to discharge leaked liquid.

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