Medical catheter testing equipment

Abstract

The invention relates to the field of medical catheter detection, and discloses medical catheter test equipment which comprises a test bed, a catheter, a peristaltic pump and a water tank, a linear guide rail is arranged on the test bed, a fixed first platform and a sliding second platform are arranged on the linear guide rail, and the catheter is arranged between the first platform and the second platform. A peristaltic pump and a water tank are arranged on the side face of the test bed. The peristaltic pump sucks liquid from the water tank through a guide pipe and discharges the liquid back to the water tank. Compared with the prior art, the device has the advantages that interference of connecting parts on measurement results can be effectively eliminated, the data accuracy is improved, the laser collimator and the reflector system are introduced, the coaxiality of the first / second pipeline connector is ensured through optical calibration, the problem of measurement errors caused by guide pipe bending or installation deviation is solved, and the measurement accuracy is improved. And a sealing structure of the connecting nozzle and the sealing sliding sleeve is adopted, so that the sealing performance is ensured, the dismounting and mounting process of the conduit is simplified, and the experimental operation is more convenient.

Description

Technical Field

[0001] The invention relates to the field of medical catheter detection, in particular to a medical catheter testing device. Background Art

[0002] Medical catheters are important tools for diagnosis, treatment or monitoring in the medical field. They are widely used in fluid delivery, drainage, interventional operations, etc. between human cavities, blood vessels or tissues. For chemotherapy, insulin pumps and other scenarios, precise drug delivery requires catheters.

[0003] For such application scenarios, a peristaltic pump is required to accurately control the drug delivery speed. However, due to the objective resistance along the fluid during transportation in the pipeline, the resistance of the medical catheter will make it difficult to accurately control the drug delivery speed. In this regard, the applicant company will coat or plate the inner wall of the catheter when producing it to reduce the pipeline resistance.

[0004] In the actual research and development of catheter inner wall coatings, researchers need to verify the effectiveness of the coating and the degree of reduction in pipe resistance through experiments. However, there is currently a lack of specialized testing equipment, and existing pipeline resistance testing devices cannot be used to test medical catheters. Summary of the invention

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

[0006] In order to solve the above technical problems, the technical solution provided by the present invention is: a medical catheter testing equipment, which includes a test bench, a catheter, a peristaltic pump and a water tank. The test bench is provided with a linear guide rail, and the linear guide rail is provided with a fixed first platform and a sliding second platform. 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 adjustable direction is provided on the second platform. Both ends of the conduit 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, the first pipe connector and the second pipe connector are both provided with a central hole in the center, a pressure measuring hole connected to the first pressure transmitter and the second pressure transmitter is provided on the top of the central hole, and a connecting hole is provided on the side.

[0009] Furthermore, a light-transmitting mirror is provided at the end of the center hole for sealing, a laser collimator is provided at the outer side of the end of the center hole of the first pipe connector, and a laser reflector is provided at the outer side of the end of the center hole of the second pipe connector.

[0010] Furthermore, the peristaltic pump inlet 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 peristaltic pump outlet is connected to the water tank conduit.

[0011] Furthermore, connecting nozzles are sleeved in the tubes at both ends of the conduit, the outer tubes are sleeved with sealing sleeves, the outer threads of the connecting nozzles are connected to sealing rings, and a spiral spring is provided inside the sealing ring to press the sealing sleeve against the connecting nozzles.

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

[0013] Furthermore, the second platform is provided with a first hand screw for driving the translation platform to move, the translation platform is provided with a second hand screw for driving the horizontal rotation platform to rotate, and the horizontal rotation platform is provided with a third hand screw for driving the second pipe connector to rotate.

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

[0015] Furthermore, the test bench is provided with a fifth hand-cranked screw for driving the second platform to move, a magnetic scale is arranged on the outside of the linear guide rail, and a displacement encoder cooperating with the magnetic scale is arranged on the outside of the second platform.

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

[0017] 1. Measure and calculate the resistance change ∆P by using multiple length catheter segments f , effectively eliminating the interference of connecting components on the measurement results and improving data accuracy.

[0018] 2. The laser collimator and reflector system are introduced to ensure the coaxiality of the first / second pipe connector through optical calibration, solving the measurement error problem caused by pipe bending or installation offset.

[0019] 3. The sealing structure of the connecting nozzle and the sealing sleeve simplifies the catheter disassembly and assembly process while ensuring the sealing performance. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

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

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

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

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

[0028] Fig. 9 It is a structural schematic diagram of the catheter bracket of the present invention.

[0029] Fig.10 It is a schematic structural diagram of the magnetic scale of the present invention.

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

[0031] As shown in the figure: 1. test bench, 2. linear guide, 3. first platform, 4. second platform, 5. catheter, 6. peristaltic pump, 7. water tank, 8. connecting nozzle, 9. sealing ring, 10. coil spring, 11. sealing sleeve, 12. first pipe connector, 13. first pressure transmitter, 14. light transmittance mirror, 15. laser collimator, 16. center hole, 17. connecting hole, 18. pressure measuring hole, 19. translation guide, 20. translation platform, 21. horizontal rotation platform, 22. second pipe connector, 23. first hand screw, 24. second hand screw, 25. third hand screw, 26. second pressure transmitter, 27. laser reflector, 28. catheter bracket, 29. inclined slider, 30. fourth hand screw, 31. gear, 32. fifth hand screw, 33. magnetic scale, 34. displacement encoder. DETAILED DESCRIPTION

[0032] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0033] According to the Darcy-Weisbach formula:

[0034]

[0035] Where f is the friction coefficient, which is only related to the Reynolds number and the roughness of the pipe wall. It can be used to represent the pipe resistance of the pipeline. Based on this, the Darcy-Weisbach formula is simply transformed to obtain:

[0036]

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

[0038] Accordingly, combined with the attached Figure 1 and attached Fig.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. The test bench 1 is provided with a linear guide rail 2, and the linear guide rail 2 is provided with a fixed first platform 3 and a sliding second platform 4. 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] Combined with 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 direction is provided on the second platform 4. Both ends of the conduit 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. A center hole 16 is provided in the center of the first pipe connector 12 and the second pipe connector 22. A pressure measuring hole 18 connected to the first pressure transmitter 13 and the second pressure transmitter 26 is provided on the top of the center hole 16, and a connecting hole 17 is provided on the side.

[0040] Combined with Fig.11 The inlet of the peristaltic pump 6 is connected to the conduit of the connecting hole 17 of the first pipe connector 12, the water tank 7 is connected to the conduit of the connecting hole 17 of the second pipe connector 22, and the outlet of the peristaltic pump 6 is connected to the conduit of the water tank 7.

[0041] During the experiment of the device, the detection liquid contained in the water tank 7 can be pure water, or it can be replaced according to the liquid designed to be transported by the catheter 5 to be tested, such as plasma simulation liquid, physiological saline, etc. When the peristaltic pump 6 is working, the detection liquid contained in the water tank 7 is sucked into the second pipe connector 22, the catheter 5, the first pipe connector 12 in sequence and finally returns to the water tank 7 through the catheter in the peristaltic pump 6. In this process, the first pressure transmitter 13 and the second pressure transmitter 26 are used to detect the pressure of the detection liquid flowing at their installation positions respectively. By comparing the pressure values ​​of the two pressure transmitters, the resistance change ∆P of the pipeline composed of all components between the two can be obtained. f .

[0042] When the above structure is implemented, the first pressure transmitter 13 and the second pressure transmitter 26 use pressure transmitters with single crystal silicon MEMS sensors to perform high-sensitivity pressure detection, and the peristaltic pump 6 uses a model with a fixed flow rate to ensure consistent 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 is a common technology and is not further described in this application.

[0043] Combined with Figure 2 and attached Figure 3 The ends of both sides of the conduit 5 are sleeved with connecting nozzles 8, the outer tube is sleeved with a sealing sleeve 11, the external thread of the connecting nozzle 8 is connected to a sealing ring 9, a spiral spring 10 is provided inside the sealing ring 9 to press the sealing sleeve 11 against the connecting nozzle 8, and a flange connection is set between the connecting nozzle 8 and the center holes 16 of the first pipe connector 12 and the second pipe connector 22.

[0044] In the above structure, the outer wall of the connecting nozzle 8 and the inner wall of the sealing sleeve 11 squeeze the catheter 5 from the inside and outside to form a seal. Through this structure, the sealed connection of the catheter 5 to be tested can be achieved. The flange connection between the connecting nozzle 8 and the center hole 16 can facilitate the disassembly and replacement of the catheter 5.

[0045] Since the connection structure formed by the above components has some influence on the resistance of the pipeline formed by them, in order to eliminate the influence of the pressure transmitter on the measured resistance change ∆P f When using this device to detect a certain type of catheter 5, it is necessary to cut catheters 5 of different lengths, record them as D1, D2...Dn, install them in this device respectively, and measure the resistance change ∆P f Test and obtain multiple sets of resistance changes, recorded 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 of the measured catheter 5 at the corresponding length of D2-D1. According to this method, multiple catheters 5 of different lengths can be appropriately measured and ∆P can be calculated. f .

[0046] When the above test method is implemented, the length of the catheter 5 to be tested can be selected and cut according to the length required in actual use. For example, the midline catheter required for chemotherapy drug infusion is generally about 200 mm. When testing, the ∆P under the 100 mm catheter 5 to be tested can be measured respectively. f 1, and ∆P under 300mm test conduit 5 f 2. Use ∆P f 2-∆P f 1 represents ∆P under 200mm of the tested pipe 5 f .

[0047] Combined with Fig.10 The test bench 1 is provided with a fifth hand-cranked screw rod 32 for driving the second platform 4 to move, a magnetic scale 33 is arranged on the outer side of the linear guide rail 2, and a displacement encoder 34 cooperating with the magnetic scale 33 is arranged on the outer side of the second platform 4.

[0048] When it is necessary to detect catheters 5 of 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 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 of different lengths.

[0049] The above test method can only be used to detect the resistance along the straight tube. However, for medical catheters, it is difficult to keep the catheter 5 in a straight state when testing it. In addition, since catheters 5 of different lengths need to be tested, the pipeline needs to be disassembled and assembled many times. During the disassembly and assembly process, the first pipeline connector 12 or the second pipeline connector 22 may be offset. If the first pipeline connector 12 or the second pipeline connector 22 is offset, the central hole 16 inside it cannot be on the same axis, which may easily cause the pipeline formed by the catheter 5 to be uneven.

[0050] Combined with Figure 4 and attached Figure 8 A light-transmitting mirror 14 is provided at the end of the center hole 16 for sealing, a laser collimator 15 is provided at the outer side of the end of the center hole 16 of the first pipe connector 12 , and a laser reflecting mirror 27 is provided at the outer side of the end of the center hole 16 of the second pipe connector 22 .

[0051] The laser collimator 15 and the laser reflector 27 can form a laser alignment detection system, wherein the laser collimator 15 is installed with the first pipe connector 12 through a coaxial positioning rod and kept coaxial with the center hole 16. The laser rays generated by the laser collimator 15 can represent the axis of the center hole 16 of the first pipe connector 12. In addition, the laser reflector 27 is also installed with the second pipe connector 22 through a coaxial positioning rod and kept coaxial with the center hole 16. The laser collimator 15 emits a parallel laser beam to the laser reflector 27 and reflects it back into the laser collimator 15. The laser detection device in the laser collimator 15 can compare the emitted light beam with the reflected light beam, and thereby determine whether the first pipe connector 12 and the second pipe connector 22 are coaxial.

[0052] Combined with Figure 6 and attached Figure 7 The second platform 4 is provided with a translation guide rail 19, on which a translation platform 20 is slidingly connected, on which a horizontal rotating platform 21 is rotationally connected, and a second pipe connector 22 is vertically rotated and arranged on the horizontal rotating platform 21, and the second platform 4 is provided with a first hand-cranked screw rod 23 for driving the translation platform 20 to move, and the translation platform 20 is provided with a second hand-cranked screw rod 24 for driving the horizontal rotating platform 21 to rotate, and the horizontal rotating platform 21 is provided with a third hand-cranked screw rod 25 for driving the second pipe connector 22 to rotate. In each of the above-mentioned hand-cranked screw rods, the screw rods and the hand crank handles need to be connected in power through a worm gear reduction mechanism. In addition to reducing the hand cranking speed to make the angle and azimuth adjustment more precise, the self-locking characteristics of the 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] The position and orientation of the second pipe connector 22 can be adjusted by the above mechanism, and the second pipe connector 22 can be adjusted to be coaxial with the first pipe connector 12 in cooperation with the laser collimator 15 and the laser reflector 27 .

[0054] Combined with Fig. 9The linear guide rail 2 is provided with a catheter bracket 28, 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 opposite to each other. The catheter bracket 28 is provided with a fourth hand screw 30 for driving the inclined plane slider 29 to move. A total of two fourth hand screws 30 are provided for driving the two inclined plane sliders 29 respectively. Gears 31 are provided at both ends of the fourth hand screw 30. The gears 31 of the two fourth hand screws 30 are meshed with each other. The spacing between the two inclined plane sliders 29 can be adjusted by rotating the fourth hand screw 30. The fourth hand screw 30 is placed under the catheter 5 to be tested, so that the inclined plane of the inclined plane slider 29 can lift and support the catheter 5. The lifting height can be adjusted by changing the spacing between the two inclined plane sliders 29 to ensure the straightness of the catheter 5. In addition, if a catheter 5 with a longer length needs to be tested, multiple catheter brackets 28 can be placed on the linear guide rail 2 to support different positions.

[0055] When the above structure is implemented, before installing the catheter 5 to be tested, the position of the second platform 4 is first adjusted to be at the closest distance to the first platform 3, the laser collimator 15 is started to perform coaxiality detection, the orientation and angle of the second pipe connector 22 are adjusted to be coaxial with the first pipe connector 12, and then the second platform 4 is moved to the farthest distance from the first platform 3, and the coaxial adjustment is repeated to ensure that the second pipe connector 22 is always coaxial with the first pipe connector 12 when the second platform 4 is at the closest and farthest distance from the first platform 3.

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

[0057] The present invention and its implementation methods are described above, and such description is not restrictive, and the actual structure is not limited thereto. In short, if a person skilled in the art is inspired by it, and does not deviate from the purpose of the invention, and does not creatively design a structure and implementation method similar to the technical solution, they should all fall within the protection scope of the present invention.

Claims

1. A medical catheter testing device, comprising a test bench (1), a catheter (5), a peristaltic pump (6) and a water tank (7), wherein the test bench (1) is provided with a linear guide rail (2), the linear guide rail (2) is provided with a fixed first platform (3) and a sliding second platform (4), 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), characterized in that: The first platform (3) is provided with a fixed first pipeline connector (12), the second platform (4) is provided with a second pipeline connector (22) with an adjustable orientation, the two ends of the conduit (5) are respectively connected to the first pipeline connector (12) and the second pipeline connector (22), a first pressure transmitter (13) is provided on the top of the first pipeline connector (12), and a second pressure transmitter (26) is provided on the top of the second pipeline connector (22).

2. The medical catheter testing device according to claim 1, characterized in that: The first pipe connector (12) and the second pipe connector (22) are both provided with a central hole (16) in the middle, 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 connecting hole (17) is provided on the side.

3. The medical catheter testing device according to claim 2, characterized in that: A light-transmitting mirror (14) is provided at the end of the central hole (16) for sealing, a laser collimator (15) is provided on the outside of the end of the central hole (16) of the first pipe connector (12), and a laser reflector (27) is provided on the outside of the end of the central hole (16) of the second pipe connector (22).

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

5. The medical catheter testing device according to claim 1, characterized in that: The ends of both sides of the conduit (5) are provided with connecting nozzles (8) in the tubes, the outer tubes are connected with sealing sleeves (11), the outer surfaces of the connecting nozzles (8) are threadedly connected to sealing rings (9), and the sealing rings (9) are provided with coil springs (10) inside to press the sealing sleeves (11) against the connecting nozzles (8).

6. The medical catheter testing device according to claim 1, characterized in that: The second platform (4) is provided with a translation guide rail (19), a translation platform (20) is slidably connected to the translation guide rail (19), a horizontal rotation platform (21) is rotationally connected to the translation platform (20), and a second pipe connector (22) is vertically rotationally arranged on the horizontal rotation platform (21).

7. The medical catheter testing device according to claim 1, characterized in that: The second platform (4) is provided with a first hand-cranked screw (23) for driving the translation platform (20) to move, the translation platform (20) is provided with a second hand-cranked screw (24) for driving the horizontal rotation platform (21) to rotate, and the horizontal rotation platform (21) is provided with a third hand-cranked screw (25) for driving the second pipe connector (22) to rotate.

8. The medical catheter testing device according to claim 1, characterized in that: The linear guide rail (2) is provided with a catheter bracket (28), the catheter bracket (28) is provided with a pair of inclined plane sliders (29), the inclined planes of the two inclined plane sliders (29) are arranged opposite to each other, and the catheter bracket (28) is provided with a fourth hand-cranked screw rod (30) for driving the inclined plane sliders (29) to move.

9. The medical catheter testing device according to claim 1, characterized in that: The test bench (1) is provided with a fifth hand-cranked screw rod (32) for driving the second platform (4) to move, a magnetic scale (33) is arranged outside the linear guide rail (2), and a displacement encoder (34) matching the magnetic scale (33) is arranged outside the second platform (4).

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