A medical catheter testing device

Abstract

The present invention relates to the field of medical catheter detection. The present invention discloses a medical catheter testing device, which includes a test bench, a catheter, a peristaltic pump and a water tank. A linear guide rail is provided on the test bench, and a fixed first platform and a sliding second platform are provided on the linear guide rail. The catheter is arranged between the first platform and the second platform. A peristaltic pump and a water tank are provided on the side of the test bench. The peristaltic pump sucks liquid from the water tank through the catheter and discharges it back into the water tank. The advantages of the present invention compared with the prior art are as follows: it can effectively eliminate the interference of the connecting components on the measurement results and improve the data accuracy. A laser collimator and a mirror system are introduced to ensure the coaxiality of the first / second pipe connectors through optical calibration, and solve the measurement error problem caused by catheter bending or installation deviation. A sealing structure of a connecting nozzle and a sealing sliding sleeve is adopted, which simplifies the catheter disassembly and assembly process while ensuring the sealing performance, making the experimental operation more convenient.

Description

Technical Field

[0001] The present invention relates to the field of medical catheter detection, and specifically refers to a medical catheter testing device. Background Art

[0002] Medical catheters are important tools used in the medical field for diagnosis, treatment, or monitoring, and are widely used in the delivery, drainage, and interventional operations of fluids in human body cavities, blood vessels, or tissues. For scenarios such as chemotherapy and insulin pumps, precise drug delivery needs to be carried out through catheters.

[0003] For such application scenarios, a peristaltic pump needs to be used to control the precise drug delivery speed. However, due to the objective existence of frictional resistance during fluid transportation in the pipeline, the resistance of the medical catheter makes it difficult to control the drug delivery speed very precisely. In this regard, when the applicant's enterprise manufactures catheters, the inner wall thereof will be coated or plated to reduce the pipeline resistance.

[0004] In the actual R & D process of the inner wall coating of the catheter, R & D personnel need to verify the effectiveness of the coating and the degree of pipe resistance reduction through experiments. However, there is currently a lack of dedicated testing equipment, and existing pipeline resistance testing devices cannot be used to detect medical catheters. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that existing pipeline resistance testing devices cannot be used to detect medical catheters, and there is a lack of a dedicated pipe resistance testing device for medical catheters. The present invention provides a medical catheter testing device.

[0006] To solve the above technical problems, the technical solution provided by the present invention is: a medical catheter testing device, which includes a test bench, a catheter, a peristaltic pump, and a water tank. A linear guide rail is provided on the test bench, and a fixed first platform and a sliding second platform are provided on the linear guide rail. The catheter is arranged between the first platform and the second platform. A peristaltic pump and a water tank are provided on the side of the test bench. The peristaltic pump sucks liquid from the water tank through the catheter and discharges it back to the water tank.

[0007] A fixed first pipe connector is provided on the first platform, and a second pipe connector with an adjustable orientation is provided on the second platform. Both ends of the catheter are respectively connected to the first pipe connector and the second pipe connector. A first pressure transmitter is provided on the top of the first pipe connector, and a second pressure transmitter is provided on the top of the second pipe connector.

[0008] Furthermore, central holes are provided in the centers of both the first pipe connector and the second pipe connector. A pressure measurement hole connected to the first pressure transmitter and the second pressure transmitter is provided on the top of the central hole, and a connection hole is provided on the side.

[0009] Further, a light-transmitting mirror is provided at the end of the central hole for sealing. A laser collimator is provided outside the end of the central hole of the first pipe connector, and a laser reflector is provided outside the end of the central hole of the second pipe connector.

[0010] Further, the inlet of the peristaltic pump is connected to the connecting hole conduit of the first pipe connector, the water tank is connected to the connecting hole conduit of the second pipe connector, and the outlet of the peristaltic pump is connected to the water tank conduit.

[0011] Further, connecting nozzles are sleeved inside the end pipes on both sides of the conduit, a sealing sliding sleeve is sleeved outside the pipe, the outside of the connecting nozzle is threadedly connected with a sealing ring, and a spiral spring is arranged inside the sealing ring to press the sealing sliding sleeve against the connecting nozzle.

[0012] Further, a translation guide rail is provided on the second platform, a translation platform is slidably connected to the translation guide rail, a horizontal rotation platform is rotatably connected to the translation platform, and the second pipe connector is vertically rotatably arranged on the horizontal rotation platform.

[0013] Further, a first hand-operated lead screw for driving the translation platform to move is provided on the second platform, a second hand-operated lead screw for driving the horizontal rotation platform to rotate is provided on the translation platform, and a third hand-operated lead screw for driving the second pipe connector to rotate is provided on the horizontal rotation platform.

[0014] Further, a conduit bracket is provided on the linear guide rail, a pair of inclined plane sliders are provided on the conduit bracket, the inclined planes of the two inclined plane sliders are arranged opposite to each other, and a fourth hand-operated lead screw for driving the inclined plane sliders to move is provided on the conduit bracket.

[0015] Further, a fifth hand-operated lead screw for driving the second platform to move is provided on the test bench, a magnetic grating ruler is arranged outside the linear guide rail, and a displacement encoder for cooperating with the magnetic grating ruler is arranged outside the second platform.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1. By measuring and calculating the resistance change amount ∆P in segments with conduits of multiple lengths f , the interference of the connecting components to the measurement result is effectively eliminated, and the data accuracy is improved.

[0018] 2. The laser collimator and the mirror system are introduced, and the coaxiality of the first / second pipe connectors is ensured through optical calibration, solving the measurement error problem caused by the bending or installation offset of the conduit.

[0019] 3. The sealing structure of the connecting nozzle and the sealing sliding sleeve is adopted, which simplifies the disassembly and assembly process of the conduit while ensuring the sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of the present invention.

[0021] Figure 2 It is a schematic structural view of the connecting nozzle of the present invention.

[0022] Figure 3 It is a schematic cross-sectional structural view of the sealing ring of the present invention.

[0023] Figure 4 It is a schematic structural view of the first platform of the present invention.

[0024] Figure 5 It is a schematic structural view of the central hole of the present invention.

[0025] Figure 6 It is a schematic structural view of the second platform of the present invention.

[0026] Figure 7 It is a schematic view of the angle and azimuth adjustment of the second pipe connector of the present invention.

[0027] Figure 8 It is a schematic structural view of the second pipe connector of the present invention.

[0028] Figure 9 It is a schematic structural view of the conduit bracket of the present invention.

[0029] Figure 10 It is a schematic structural view of the magnetic grating ruler of the present invention.

[0030] Figure 11 It is a schematic view of the pipeline connection sequence of the present invention.

[0031] As shown in the figure: 1. Test bench, 2. Linear guide rail, 3. First platform, 4. Second platform, 5. Conduit, 6. Peristaltic pump, 7. Water tank, 8. Connecting nozzle, 9. Sealing ring, 10. Helical spring, 11. Sealing sliding sleeve, 12. First pipe connector, 13. First pressure transmitter, 14. Transparent mirror, 15. Laser collimator, 16. Central hole, 17. Connecting hole, 18. Pressure measuring hole, 19. Translation guide rail, 20. Translation platform, 21. Horizontal rotating platform, 22. Second pipe connector, 23. First hand-operated screw rod, 24. Second hand-operated screw rod, 25. Third hand-operated screw rod, 26. Second pressure transmitter, 27. Laser reflector, 28. Conduit bracket, 29. Inclined plane slider, 30. Fourth hand-operated screw rod, 31. Gear, 32. Fifth hand-operated screw rod, 33. Magnetic grating ruler, 34. Displacement encoder. Detailed implementation mode

[0032] The present invention will be further described in detail below with reference to the accompanying drawings.

[0033] According to the Darcy-Weisbach formula, it can be known that:

[0034]

[0035] Where f is the friction coefficient, which is only related to the Reynolds number and the pipe wall roughness and can be used to represent the pipe resistance. Based on this, after simply transforming the Darcy - Weisbach formula, we get:

[0036]

[0037] It can be seen from this that by measuring the change in resistance ∆P at both ends of the medical catheter during liquid transportation f , the inner diameter D of the catheter, the length L of the catheter, the fluid velocity v, and the fluid density ρ, the friction coefficient f of the catheter can be obtained.

[0038] Based on this, in combination with Attached Figure 1 and Attached Figure 11 , the present application provides a medical catheter testing device, which includes a test bench 1, a catheter 5, a peristaltic pump 6, and a water tank 7. A linear guide rail 2 is provided on the test bench 1, and a fixed first platform 3 and a sliding second platform 4 are provided on the linear guide rail 2. The catheter 5 is arranged between the first platform 3 and the second platform 4. A peristaltic pump 6 and a water tank 7 are provided on the side of the test bench 1. The peristaltic pump 6 sucks liquid from the water tank 7 through the catheter 5 and discharges it back to the water tank 7.

[0039] In combination with Attached Figure 4 and Attached Figure 5 , a fixed first pipe connector 12 is provided on the first platform 3, and a second pipe connector 22 with adjustable orientation is provided on the second platform 4. Both ends of the catheter 5 are connected to the first pipe connector 12 and the second pipe connector 22 respectively. A first pressure transmitter 13 is provided on the top of the first pipe connector 12, and a second pressure transmitter 26 is provided on the top of the second pipe connector 22. Central holes 16 are provided in the centers of both the first pipe connector 12 and the second pipe connector 22. Pressure measurement holes 18 connected to the first pressure transmitter 13 and the second pressure transmitter 26 are provided on the top of the central holes 16, and connection holes 17 are provided on the side.

[0040] In combination with Attached Figure 11 , the inlet of the peristaltic pump 6 is connected to the connection hole 17 of the first pipe connector 12 through a catheter, the water tank 7 is connected to the connection hole 17 of the second pipe connector 22 through a catheter, and the outlet of the peristaltic pump 6 is connected to the water tank 7 through a catheter.

[0041] When the device is under experiment, the detection liquid contained in the water tank 7 can be pure water, or can be replaced according to the liquid for transportation designed for the conduit 5 to be measured, such as plasma simulation liquid, physiological saline, etc. When the peristaltic pump 6 works, it successively sucks the detection liquid contained in the water tank 7 into the second pipe connector 22, the conduit 5, the first pipe connector 12 and finally returns to the water tank 7 through the conduit in the peristaltic pump 6. During this process, the pressure transmitter 13 and the second pressure transmitter 26 respectively detect the pressure when the detection liquid flows at their installation positions, and the resistance change amount ∆P of the pipeline formed by all components between the two can be obtained by comparing the pressure values of the two pressure transmitters. f 。

[0042] When the above structure is specifically implemented, the first pressure transmitter 13 and the second pressure transmitter 26 are selected as pressure transmitters with single-crystal silicon MEMS sensors for high-sensitivity pressure detection. The peristaltic pump 6 is selected with a model that can fix the flow rate to ensure the same fluid velocity during the experiment. In addition, a computer is required to receive and process the pressure signals output by the first pressure transmitter 13 and the second pressure transmitter 26. The corresponding computer software belongs to common technology and will not be further described in this application.

[0043] Combined with the attached Figure 2 and the attached Figure 3 , connection nozzles 8 are sleeved and arranged inside the two end pipes on both sides of the conduit 5, and a sealing sliding sleeve 11 is sleeved outside the pipe. The external thread of the connection nozzle 8 is connected to a sealing ring 9, and a spiral spring 10 is arranged inside the sealing ring 9 to press the sealing sliding sleeve 11 against the connection nozzle 8. A flange connection is set between the connection nozzle 8 and the central holes 16 of the first pipe connector 12 and the second pipe connector 22.

[0044] In the above structure, the outer wall of the connection nozzle 8 and the inner wall of the sealing sliding sleeve 11 respectively squeeze the conduit 5 from the inside and outside to form a seal. Through this structure, the sealed connection of the conduit 5 to be measured can be realized. The flange connection between the connection nozzle 8 and the central hole 16 can facilitate the disassembly and replacement of the conduit 5.

[0045] Since the connection structure formed by the above components has an impact on the resistance of the pipeline formed by it, in order to eliminate the interference caused to the measurement of the resistance change amount ∆P f by the pressure transmitter, when detecting a certain type of conduit 5 with this device, conduits 5 of different lengths need to be intercepted, denoted as D1, D2... Dn, and they are respectively installed on this device, and the resistance change amount ∆P f is detected to obtain multiple groups of resistance change amounts, denoted as ∆P f 1, ∆P f 2... ∆P f n. By calculating ∆P f 2 - ∆P f 1, the obtained ∆P fIt can represent the resistance change amount of the catheter 5 to be measured corresponding to the length from D2 to D1. Multiple catheters 5 with different lengths can be appropriately measured according to this method and ∆P can be calculated. f 。

[0046] When the above test method is specifically implemented, it can be selected and intercepted according to the length required for the catheter 5 to be measured in actual use. For example, the midline catheter required for chemotherapy drug infusion is generally about 200 mm. Then, when detecting, ∆P under the 100 mm catheter 5 to be measured can be measured respectively. f 1, and ∆P under the 300 mm catheter 5 to be measured. f 2, using ∆P f 2 - ∆P f 1 represents ∆P under the 200 mm catheter 5 to be measured. f 。

[0047] Combined with the attached Figure 10 In the test bench 1, there is a fifth hand-operated lead screw 32 for driving the movement of the second platform 4. A magnetic grating ruler 33 is arranged outside the linear guide 2, and a displacement encoder 34 for cooperating with the magnetic grating ruler 33 is arranged outside the second platform 4.

[0048] When it is necessary to detect catheters 5 with different lengths, the second platform 4 needs to be moved according to the length of the catheter 5. The experimenter can manually operate the fifth hand-operated lead screw 32 to move the second platform 4, and detect the moving distance of the second platform 4 according to the displacement encoder 34 to adapt to catheters 5 with different lengths.

[0049] The above test method can only be used to detect the frictional resistance along the straight pipe. However, for medical catheters, it is very difficult to keep the catheter 5 in a straight state during the test. And because it is necessary to detect catheters 5 with different lengths, the pipeline needs to be disassembled and assembled multiple times. During the disassembly and assembly process, it is possible that the first pipeline connector 12 or the second pipeline connector 22 is offset. If the first pipeline connector 12 or the second pipeline connector 22 is offset, the central holes 16 inside them cannot be on the same axis, which is also likely to cause the pipeline formed by the catheter 5 to be uneven.

[0050] Combined with the attached Figure 4 and the attached Figure 8 In the end of the central hole 16, a light-transmitting mirror 14 is arranged for sealing. Outside the end of the central hole 16 of the first pipeline connector 12, a laser collimator 15 is arranged, and outside the end of the central hole 16 of the second pipeline connector 22, a laser reflector 27 is arranged.

[0051] The laser collimator 15 and the laser mirror 27 can form a laser collimation detection system. The laser collimator 15 is installed through a coaxial positioning rod with the first pipe connector 12 and is coaxial with the central hole 16. The laser ray emitted by the laser collimator 15 can represent the axis where the central hole 16 of the first pipe connector 12 is located. In addition, the laser mirror 27 is also installed through a coaxial positioning rod with the second pipe connector 22 and is coaxial with the central hole 16. The laser collimator 15 emits a parallel laser beam to the laser mirror 27 and the beam is reflected back into the laser collimator 15. The laser detection device in the laser collimator 15 can compare the emitted beam and the reflected beam, and thereby determine whether the first pipe connector 12 and the second pipe connector 22 are coaxial.

[0052] Combined with the attached Figure 6 and the attached Figure 7 On the second platform 4, there is a translation guide rail 19. A translation platform 20 is slidably connected to the translation guide rail 19. A horizontal rotation platform 21 is rotatably connected to the translation platform 20. The second pipe connector 22 is vertically rotatably arranged on the horizontal rotation platform 21. On the second platform 4, there is a first hand-operated screw rod 23 for driving the translation platform 20 to move. On the translation platform 20, there is a second hand-operated screw rod 24 for driving the horizontal rotation platform 21 to rotate. On the horizontal rotation platform 21, there is a third hand-operated screw rod 25 for driving the second pipe connector 22 to rotate. Between the screw rod and the hand-operating handle of each of the above hand-operated screw rods, a worm and worm gear reduction mechanism is required for power connection. In addition to reducing the hand-operating speed to make the angle and azimuth adjustment more accurate, the self-locking characteristic of the worm and worm gear reduction mechanism can ensure that the angle and azimuth of the second pipe connector 22 will not be easily changed due to external force collision.

[0053] Through the above mechanism, the position and orientation of the second pipe connector 22 can be adjusted, and in cooperation with the laser collimator 15 and the laser mirror 27, the second pipe connector 22 can be adjusted to be coaxial with the first pipe connector 12.

[0054] Combined with the attached Figure 9, a catheter bracket 28 is provided on the linear guide rail 2, and a pair of inclined surface sliders 29 are provided on the catheter bracket 28. The inclined surfaces of the two inclined surface sliders 29 are arranged oppositely. A fourth hand-operated lead screw 30 for driving the inclined surface slider 29 to move is provided on the catheter bracket 28. A total of two fourth hand-operated lead screws 30 are provided to drive the two inclined surface sliders 29 respectively. Gears 31 are provided at both ends of the fourth hand-operated lead screw 30. The gears 31 of the two fourth hand-operated lead screws 30 are meshed with each other. By rotating the fourth hand-operated lead screw 30, the distance between the two inclined surface sliders 29 can be adjusted. Place it under the catheter 5 to be measured, so that the inclined surface of the inclined surface slider 29 supports the catheter 5. By changing the distance between the two inclined surface sliders 29, the lifting height can be adjusted to ensure the straightness of the catheter 5. In addition, if it is necessary to detect a catheter 5 with a longer length, multiple catheter brackets 28 can also be placed on the linear guide rail 2 to support different positions.

[0055] When the above structure is specifically implemented, before installing the catheter 5 to be detected, first adjust the position of the second platform 4 so that it is at the closest distance to the first platform 3. Start the laser collimator 15 for coaxiality detection, adjust the orientation and angle of the second pipe connector 22 to make it coaxial with the first pipe connector 12, and then move the second platform 4 to the farthest distance from the first platform 3, and repeat the coaxial adjustment to ensure that when the second platform 4 is at the closest and farthest distances from the first platform 3, the second pipe connector 22 is always coaxial with the first pipe connector 12.

[0056] During the experiment, after installing or replacing the catheter 5, it is necessary to change the position of the catheter bracket 28 according to the length of the catheter 5, and perform the coaxiality adjustment of the second pipe connector 22 and the first pipe connector 12 again.

[0057] The above describes the present invention and its implementation manners. This description is not restrictive, and the actual structure is not limited thereto. All in all, if those of ordinary skill in the art are inspired by it and design similar structural manners and embodiments without creative efforts without departing from the purpose of the present invention, they shall fall within the protection scope of the present invention.

Claims

1. A medical catheter testing device, which comprises a test bench (1), a catheter (5), a peristaltic pump (6) and a water tank (7). A linear guide rail (2) is provided on the test bench (1), and a fixed first platform (3) and a sliding second platform (4) are provided on the linear guide rail (2). The catheter (5) is arranged between the first platform (3) and the second platform (4). The peristaltic pump (6) and the water tank (7) are arranged on the side of the test bench (1). The peristaltic pump (6) sucks liquid from the water tank (7) through the catheter (5) and discharges it back to the water tank (7). It is characterized in that: A fixed first pipe connector (12) is provided on the first platform (3), and a second pipe connector (22) with adjustable orientation is provided on the second platform (4). Both ends of the catheter (5) are respectively connected to the first pipe connector (12) and the second pipe connector (22). A first pressure transmitter (13) is provided on the top of the first pipe connector (12), and a second pressure transmitter (26) is provided on the top of the second pipe connector (22); Central holes (16) are provided in the centers of both the first pipe connector (12) and the second pipe connector (22). A light-transmitting mirror (14) is arranged at the end of the central hole (16) for sealing. A laser collimator (15) is arranged outside the end of the central hole (16) of the first pipe connector (12), and a laser reflector (27) is arranged outside the end of the central hole (16) of the second pipe connector (22).

2. The medical catheter testing device according to claim 1, characterized in that: A pressure measuring hole (18) connected to the first pressure transmitter (13) and the second pressure transmitter (26) is provided at the top of the central hole (16), and a connection hole (17) is provided on the side.

3. The medical catheter testing device according to claim 2, wherein: The inlet of the peristaltic pump (6) is connected to the connection hole (17) of the first pipe connector (12) by a hose, the water tank (7) is connected to the connection hole (17) of the second pipe connector (22) by a hose, and the outlet of the peristaltic pump (6) is connected to the water tank (7) by a hose.

4. The medical catheter testing device according to claim 1, wherein: Connection nozzles (8) are sleeved inside the end pipes on both sides of the catheter (5), and sealing sliding sleeves (11) are sleeved outside the pipes. The connection nozzle (8) is externally threaded and connected to a sealing ring (9), and a spiral spring (10) is arranged inside the sealing ring (9) to press the sealing sliding sleeve (11) against the connection nozzle (8).

5. The medical catheter testing device according to claim 1, wherein: A translation guide rail (19) is provided on the second platform (4), a translation platform (20) is slidably connected to the translation guide rail (19), a horizontal rotation platform (21) is rotatably connected to the translation platform (20), and the second pipe connector (22) is vertically rotatably arranged on the horizontal rotation platform (21).

6. The medical catheter testing device according to claim 5, wherein: A first hand-operated lead screw (23) for driving the translation platform (20) to move is provided on the second platform (4), a second hand-operated lead screw (24) for driving the horizontal rotation platform (21) to rotate is provided on the translation platform (20), and a third hand-operated lead screw (25) for driving the second pipe connector (22) to rotate is provided on the horizontal rotation platform (21).

7. The medical catheter testing device according to claim 1, wherein: A catheter bracket (28) is provided on the linear guide rail (2), and a pair of inclined plane sliders (29) are provided on the catheter bracket (28). The inclined planes of the two inclined plane sliders (29) are arranged oppositely, and a fourth hand-operated lead screw (30) for driving the inclined plane slider (29) to move is provided on the catheter bracket (28).

8. The medical catheter testing device according to claim 1, wherein: A fifth hand-operated lead screw (32) for driving the second platform (4) to move is provided on the test bench (1). A magnetic grating ruler (33) is arranged outside the linear guide rail (2), and a displacement encoder (34) for cooperating with the magnetic grating ruler (33) is arranged outside the second platform (4).

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