CN113156031B - Buffer damper device applied to chromatographic infusion pump - Google Patents

Abstract

The present invention discloses a buffer damper device applied to a chromatographic infusion pump, including an infusion pump equipped with a buffer damper, the infusion pump is provided with a pressure compensation device and a mainboard controller, the buffer damper includes a sensor housing, one end of the sensor housing is fixedly connected with a damper housing, the other end of the sensor housing is fixedly installed with a pressure sensor connected with the mainboard controller, one end of the sensor housing is provided with a circular convex groove, one side of the sensor housing is provided with a liquid outlet connected with the circular convex groove, and the liquid outlet is connected with a buffer tube. In the present invention, the flow rate is fine-tuned by compensating for pressure fluctuations of the pressure sensor, and part of the insufficient liquid is supplemented, so as to achieve the purpose of alleviating flow pulsation, and the flow adjustment or pressure range is not limited by the properties of the deformable material, the volume is small, the structure is simple, the use is convenient, and the cost is low.

Description

A buffer damper device used in chromatographic infusion pump

Technical Field

The invention relates to the technical field of chromatographic infusion pumps, and in particular to a buffer damper device applied to chromatographic infusion pumps.

Background Art

High-performance liquid chromatography infusion pumps often use a series or parallel reciprocating plunger pump structure. During the continuous infusion process, the plunger often produces flow pulsation during the alternating movement in the pump chamber. For the chromatographic analysis process, the stability of the flow will affect the repeatability of the separation results. Generally, the same test is performed under the same conditions, and the relative standard deviation of the results is obtained. For the liquid chromatography system, if the flow is unstable, the separation process is difficult to stabilize, and the repeatability of the chromatographic separation results is low, which increases the relative standard deviation. Therefore, it is necessary to eliminate or reduce the flow pulsation.

A pulsation damper is a commonly used device for reducing flow pulsation. It is usually installed near the outlet of an infusion pump. Its working principle is to use a material with a certain elastic or inelastic deformation ability inside to alleviate the impact of flow pulsation. When the pulsation causes the flow to increase, the volume of the deformed material decreases, and the volume of the internal flow path cavity increases through the conduction of the diaphragm to store some excess liquid. When the pulsation causes the flow to decrease, the volume of the deformed material increases, and the volume of the internal flow path cavity decreases through the conduction of the diaphragm to supplement some of the insufficient liquid, thereby achieving the purpose of alleviating flow pulsation.

The pulsation damper of the prior art is either filled with silicone, isopropyl alcohol or other buffer media as the deformable material, or adopts a damper with adjustable damping, and both can alleviate flow pulsation under certain conditions. However, firstly, for different deformable materials, the suitable pressure range is different. When the system pressure is too low, the diaphragm cannot fully contact with the deformable material. When the system pressure is too high, it will exceed the buffer range of the deformable material or make the diaphragm reach the displacement limit. Both pressure conditions cannot alleviate the flow pulsation. In addition, the material with a smaller deformation range has a relatively small buffering effect on the pulsation, and the material with a larger deformation range may produce excessive deformation, exceeding the elastic modulus.

Secondly, the adjustable damper adjusts the size of the damping force by adjusting the area of the hole on the piston rod covered by the piston head as needed to achieve the effect of adjustable damping, but the adjustable damper is large in size, complex in device, inconvenient to use and high in cost;

Finally, for liquid chromatography systems using pulsation dampers, system pressure and flow will vary depending on experimental conditions. Therefore, a pulsation damper filled with only one buffer medium is only suitable for a certain pressure range or flow range. If you want to buffer flow pulsations under other conditions, you need to replace the pulsation damper or change its structural design, which will be greatly restricted when used.

Summary of the invention

In order to solve the problems mentioned in the above background technology, a buffer damper device applied to a chromatographic infusion pump is proposed.

In order to achieve the above object, the present invention adopts the following technical solutions:

A buffer damper device applied to a chromatographic infusion pump comprises an infusion pump equipped with a buffer damper, the infusion pump is provided with a pressure compensation device and a mainboard controller, the buffer damper comprises a sensor housing, one end of the sensor housing is fixedly connected with the damper housing, the other end of the sensor housing is fixedly installed with a pressure sensor connected to the mainboard controller, one end of the sensor housing is provided with a circular convex groove, one side of the sensor housing is provided with a liquid outlet connected with the circular convex groove, the liquid outlet is connected with a buffer tube, a first inner cavity close to the pressure sensor and a second inner cavity away from the pressure sensor are provided inside the damper housing, the first inner cavity is connected with the second inner cavity, the inner cavity diameter of the first inner cavity is larger than the outer diameter of the circular convex groove and the inner cavity diameter of the second inner cavity, a spiral groove damper is provided in the first inner cavity, a liquid inlet and an emptying outlet connected with the second inner cavity are provided on the damper housing, the second inner cavity is an emptying valve cavity, and an emptying valve tee is provided, the other end of the buffer tube is connected with the emptying outlet, and a flow switching valve connected with the mainboard controller is installed on the connecting pipeline.

As a further description of the above technical solution:

The infusion pump includes a pump housing, a slave cam, a master cam, a plunger rod, a cleaning chamber and a pump head. The pressure compensation device includes a start/stop switch and a start/stop switch sheet installed on the pump housing. A 1-2mm notch is provided on the start/stop switch sheet. The mainboard controller is connected to the start/stop switch.

As a further description of the above technical solution:

The drain valve tee comprises a drain valve housing installed in the second inner cavity, a drain valve jewel rod is sleeved inside the drain valve housing, and a rotating nut is installed at the free end of the drain valve jewel rod.

As a further description of the above technical solution:

The liquid outlet and the circular convex groove are connected through a stepped hole, the small end of the stepped hole is connected to the circular convex groove, and the large end is connected to the liquid outlet.

As a further description of the above technical solution:

The liquid inlet is arranged on the damper housing at a position close to the second inner cavity, and the drain outlet is arranged on the damper housing at a position close to the first inner cavity.

As a further description of the above technical solution:

The sensor housing and the pressure sensor are fixedly connected via a sensor fixing nut.

As a further description of the above technical solution:

The spiral groove damper is provided with a spiral groove with a depth of 1-3 mm inside, and the spiral groove damper is made of modified polytetrafluoroethylene.

As a further description of the above technical solution:

An O-shaped sealing gasket made of PEEK material is arranged between the sensor housing and the pressure sensor, and an O-shaped modified polytetrafluoroethylene sealing gasket is arranged between the sensor housing and the damper housing.

As a further description of the above technical solution:

An O-shaped sealing ring is fixedly arranged between the second inner cavity and the exhaust valve tee, and the exhaust valve tee is provided with a concave sealing member, a PEEK sealing gasket and an O-shaped polytetrafluoroethylene sealing member.

In summary, due to the adoption of the above-mentioned technical scheme, the beneficial effects of the present invention are as follows: when the flow rate is unstable due to the increase or decrease of the flow rate during the operation of the infusion pump, resulting in the pressure being inconsistent with the actual set flow rate pressure, on the one hand, the mainboard controller controls the main cam and the slave cam to change speed by sending a deceleration or acceleration signal to the stop switch, thereby changing the running speed of the plunger rod and compensating the flow rate; on the other hand, the mainboard controller controls the flow switching valve to release the stored liquid in the buffer tube to supplement the damper, or stores the liquid in the damper into the buffer tube to compensate for the flow rate, thereby achieving the purpose of stabilizing the flow rate; the pressure sensor is used to compensate for the pressure fluctuation and fine-tune the flow rate, and some of the insufficient liquid is supplemented, thereby achieving the purpose of alleviating the flow pulsation; and the flow regulation or pressure range is not limited by the properties of the deformable material, and the volume is small, the structure is simple, the use is convenient, and the cost is low.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 shows a schematic diagram of the internal structure of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG2 is a front view schematic diagram showing a connection between a buffer damper device applied to a chromatographic infusion pump and an infusion pump according to an embodiment of the present invention;

FIG3 shows a schematic top view of a connection between a buffer damper device applied to a chromatographic infusion pump and an infusion pump according to an embodiment of the present invention;

FIG4 shows a schematic side view of a sensor housing of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG5 shows a schematic cross-sectional view of a sensor housing at A-A of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG6 shows a schematic front view of a damper housing of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG7 shows a schematic side view of a damper housing of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG8 shows a schematic cross-sectional view of a damper housing of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention at position B-B;

FIG9 shows a schematic front view of a spiral grooved damping body of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG10 is a schematic top view of a spiral grooved damping body of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention;

FIG. 11 is a bottom view schematically showing a spiral groove damping body of a buffer damper device applied to a chromatographic infusion pump according to an embodiment of the present invention.

Legend:

1. Sensor housing; 101. Liquid outlet; 102. Circular convex groove; 103. Step hole; 2. Pressure sensor; 3. Sensor fixing nut; 4. Buffer tube; 5. Damper housing; 501. First inner cavity; 502. Second inner cavity; 5021. Liquid inlet; 5022. Drain outlet; 6. Drain valve tee; 61. Drain valve housing; 62. Drain valve gem rod; 63. Rotating nut; 7. Spiral groove damping body; 8. O-ring gasket; 9. O-ring modified polytetrafluoroethylene gasket; 10. Mainboard controller; 11. Stop switch; 12. Slave cam; 13. Main cam; 14. Plunger rod; 15. Cleaning chamber; 16. Pump head; 17. Flow switching valve; 18. Pump housing; 19. Stop switch plate.

DETAILED DESCRIPTION

The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

Embodiment 1

Please refer to Figures 1-11. The present invention provides a technical solution: a buffer damper device applied to a chromatographic infusion pump, including an infusion pump equipped with a buffer damper, the infusion pump is provided with a pressure compensation device and a mainboard controller 10, the buffer damper includes a sensor housing 1, one end of the sensor housing 1 is fixedly connected to a damper housing 5, the other end of the sensor housing 1 is fixedly installed with a pressure sensor 2 connected to the mainboard controller 10, the pressure sensor 2 feeds back pressure to the mainboard controller 10, the mainboard controller 10 stores real-time pressure, a circular convex groove 102 is provided at one end of the sensor housing 1, a liquid outlet 101 connected to the circular convex groove 102 is provided on one side of the sensor housing 1, the liquid outlet 101 is connected to a buffer tube 4, the length of the buffer tube 4 is not less than 10 meters, a first inner cavity 501 close to the pressure sensor 2 and a second inner cavity 502 away from the pressure sensor 2 are provided inside the damper housing 5, the first inner cavity 50 1 is communicated with the second inner cavity 502, the inner cavity diameter of the first inner cavity 501 is larger than the outer diameter of the circular convex groove 102 and the inner cavity diameter of the second inner cavity 502, a spiral groove damping body 7 is arranged in the first inner cavity 501, a liquid inlet 5021 and an emptying outlet 5022 communicated with the second inner cavity 502 are arranged on the damper housing 5, the second inner cavity 502 is an emptying valve cavity, and is provided with an emptying valve tee 6, the emptying valve tee 6 comprises an emptying valve housing 61 installed in the second inner cavity 502, an emptying valve gem rod 62 is sleeved inside the emptying valve housing 61, a rotating nut 63 is installed at the free end of the emptying valve gem rod 62, and the position of the emptying valve gem rod 62 is adjusted by adjusting the rotating nut 63 to adjust the liquid path to enter the first inner cavity 501 or the emptying outlet 5022, the other end of the buffer tube 4 is communicated with the emptying outlet 5022, and a flow switching valve 17 connected to the mainboard controller 10 is installed on the communicating pipeline;

Please refer to Figures 2 and 3. The infusion pump includes a pump housing 18, a slave cam 12, a main cam 13, a plunger rod 14, a cleaning chamber 15 and a pump head 16. The pressure compensation device includes a stop switch 11 and a stop switch sheet 19 installed on the pump housing 18. A 1-2mm notch is provided on the stop switch sheet 19. The mainboard controller 10 is connected to the stop switch 11.

When the infusion pump is running, the flow rate is unstable due to the increase or decrease of the flow rate, resulting in the pressure being inconsistent with the actual set flow rate pressure. On the one hand, the mainboard controller 10 controls the main cam 13 and the slave cam 12 to change speed by sending a deceleration or acceleration signal to the stop switch 11, thereby changing the running speed of the plunger rod 14 and compensating the flow rate. On the other hand, the mainboard controller 10 controls the flow switching valve 17 to release the stored liquid in the buffer tube 4 to replenish it in the damper, or stores the liquid in the damper into the buffer tube 4 to compensate for the flow rate and achieve the purpose of stabilizing the flow rate. The pressure sensor 2 is used to compensate for the pressure fluctuation and fine-tune the flow rate to replenish some of the insufficient liquid, thereby achieving the purpose of alleviating the flow pulsation. The flow regulation or pressure range is not limited by the properties of the deformable material, and the volume is small, the structure is simple, the use is convenient, and the cost is low.

Please refer to FIG. 1 . The liquid outlet 101 and the circular convex groove 102 are connected via a stepped hole 103 . The small end of the stepped hole 103 is connected to the circular convex groove 102 , and the large end is connected to the liquid outlet 101 .

Please refer to FIG. 1 and FIG. 6 . The liquid inlet 5021 is disposed on the damper housing 5 at a position close to the second inner cavity 502 , and the drain outlet 5022 is disposed on the damper housing 5 at a position close to the first inner cavity 501 .

Please refer to FIG. 1 , the sensor housing 1 and the pressure sensor 2 are fixedly connected via a sensor fixing nut 3 .

Please refer to FIG. 1 . A spiral groove with a depth of 1-3 mm is arranged inside the spiral groove damper 7 . The spiral groove damper 7 is made of modified polytetrafluoroethylene.

Specifically, an O-ring sealing gasket 8 made of PEEK material is arranged between the sensor housing 1 and the pressure sensor 2, and the maximum pressure resistance can reach 60MPa, so as to avoid leakage during operation. An O-ring modified polytetrafluoroethylene sealing gasket 9 is arranged between the sensor housing 1 and the damper housing 5, and has good sealing performance. An O-ring sealing ring is fixedly arranged between the second inner cavity 502 and the drain valve tee 6, and the drain valve tee 6 is provided with a concave seal, a PEEK sealing gasket and an O-ring polytetrafluoroethylene seal.

Working principle: When in use, when the infusion pump is running, the flow rate is unstable due to the increase or decrease of the flow rate, causing the pressure to be inconsistent with the actual set flow rate pressure. On the one hand, the mainboard controller 10 controls the main cam 13 and the slave cam 12 to change speed by sending a deceleration or acceleration signal to the stop switch 11, and changes the running speed of the plunger rod 14 to compensate for the flow rate. On the other hand, the mainboard controller 10 controls the flow switching valve 17 to release the stored liquid in the buffer tube 4 to supplement the damper, or stores the liquid in the damper into the buffer tube 4 to compensate for the flow and achieve the purpose of stabilizing the flow rate. The pressure sensor 2 compensates for the pressure fluctuation and fine-tunes the flow rate to supplement some of the insufficient liquid, thereby achieving the purpose of alleviating the flow pulsation. The flow regulation or pressure range is not limited by the properties of the deformable material, and the volume is small, the structure is simple, the use is convenient, and the cost is low.

The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims (9)

1. The utility model provides a be applied to chromatographic infusion pump's buffering attenuator device, its characterized in that, including installing the transfer pump of buffering attenuator, be equipped with pressure compensating device and mainboard controller (10) on the transfer pump, buffering attenuator includes sensor housing (1), sensor housing (1) one end fixedly connected with attenuator shell (5), sensor housing (1) other end fixed mounting has pressure sensor (2) that are connected with mainboard controller (10), circular tongue (102) have been seted up to sensor housing (1) one end, liquid outlet (101) with circular tongue (102) intercommunication have been seted up to sensor housing (1) one side, liquid outlet (101) intercommunication has buffer tube (4), the inside first inner chamber (501) that are close to pressure sensor (2) and the second inner chamber (502) that keep away from pressure sensor (2) that are equipped with of attenuator housing (5), first inner chamber (501) and second inner chamber (502) intercommunication, the inner chamber diameter of first inner chamber (501) is greater than circular tongue (102) and second inner chamber (502) have, the fluid outlet (502) of the inner diameter of first inner chamber (501) and second inner chamber (502) that are equipped with the spiral damper (5) is equipped with, the fluid outlet 5025 is equipped with on the inner chamber (5), the second inner cavity (502) is an emptying valve cavity and is provided with an emptying valve tee joint (6), the other end of the buffer tube (4) is communicated with an emptying outlet (5022), and a flow switching valve (17) connected with the main board controller (10) is arranged on a communicating pipeline.

2. The buffer damper device applied to the chromatographic infusion pump according to claim 1, wherein the infusion pump comprises a pump box body (18), a slave cam (12), a master cam (13), a plunger rod (14), a cleaning cavity (15) and a pump head (16), the pressure compensation device comprises a running stop switch (11) and a running stop switch piece (19) which are arranged on the pump box body (18), a notch of 1-2mm is formed in the running stop switch piece (19), and the main board controller (10) is connected with the running stop switch (11).

3. A buffer damper device for a chromatography infusion pump according to claim 1, characterized in that the evacuation valve tee (6) comprises an evacuation valve housing (61) mounted in the second inner cavity (502), an evacuation valve jewel bar (62) is sleeved inside the evacuation valve housing (61), and a swivel nut (63) is mounted at the free end of the evacuation valve jewel bar (62).

4. The buffer damper device for the chromatographic infusion pump according to claim 1, wherein the liquid outlet (101) is communicated with the circular convex groove (102) through a stepped hole (103), the small end of the stepped hole (103) is communicated with the circular convex groove (102), and the large end of the stepped hole is communicated with the liquid outlet (101).

5. A buffer damper device for a chromatography infusion pump according to claim 1, wherein the liquid inlet (5021) is arranged on the damper housing (5) near the second inner chamber (502) and the evacuation outlet (5022) is arranged on the damper housing (5) near the first inner chamber (501).

6. A buffer damper device for a chromatography infusion pump according to claim 1, characterized in that the sensor housing (1) and the pressure sensor (2) are fixedly connected by a sensor fixing nut (3).

7. The buffer damper device applied to the chromatographic infusion pump according to claim 1, wherein a spiral disc groove with the depth of 1-3mm is formed in the spiral groove damping body (7), and the spiral groove damping body (7) is made of modified polytetrafluoroethylene.

8. The buffer damper device applied to the chromatographic infusion pump according to claim 1, wherein an O-shaped sealing gasket (8) made of PEEK is arranged between the sensor housing (1) and the pressure sensor (2), and an O-shaped modified polytetrafluoroethylene sealing gasket (9) is arranged between the sensor housing (1) and the damper housing (5).

9. The buffer damper device applied to the chromatographic infusion pump according to claim 1, wherein an O-shaped sealing ring is fixedly arranged between the second inner cavity (502) and the evacuation valve tee (6), and the evacuation valve tee (6) is provided with a concave sealing piece, a PEEK sealing pad and an O-shaped polytetrafluoroethylene sealing piece.