An experimental device for in vitro simulation of degradation of cardiovascular stents

Abstract

The application discloses an experimental device for in-vitro simulation degradation of cardiovascular stents, and relates to the technical field of biomedical experimental devices, comprising a box body, a water bath mechanism, a temperature controller, a heating component, a temperature measuring component, a degradation mechanism, a deposition mechanism, a pulsatile pump and a driving mechanism, wherein the degradation mechanism comprises a shunt component, a loading connecting plate, a sliding block, a collection component and a plurality of degradation functional assemblies; the driving mechanism is connected with the bottom of the sliding block; the pulsatile pump comprises a pump body and a piston push rod; one side of the pump body is provided with an opening; the piston push rod is slidingly installed in the pump body through the opening; and the driving mechanism is connected with one side of the piston push rod. The driving mechanism is used for driving the sliding block and the piston push rod to synchronously perform periodic reciprocating motion. The experimental device can synchronously simulate the periodic action of a blood vessel wall and blood pulsation on the cardiovascular stent, realizes real-time simulation of the stent degradation environment, and improves the accuracy of experimental results.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of biomedical experimental devices, in particular to an experimental device for simulating in vitro degradation of a cardiovascular stent. BACKGROUND

[0002] Biodegradable vascular stents are usually made of biodegradable high molecular polymers and alloy materials. After being implanted into the human body, they can mechanically support the narrow coronary blood vessels, and then the stents slowly degrade and are absorbed by the tissue. Many degradation indicators of the stent will have an important influence on its service performance, for example, the degradation rate of the stent will determine its service cycle, and the degradation form and products will affect its biocompatibility, etc. In vitro degradation experiment is one of the important ways to evaluate the degradation performance of the stent. This method usually simulates the service environment of the stent in vitro, that is, the stent is soaked in a simulated body fluid at a constant temperature, and its morphology is observed and its degradation products are analyzed, so that the degradation mechanism of the stent can be obtained relatively quickly and the degradation cycle can be extrapolated.

[0003] The patent with publication number CN114720631A provides an in vitro degradation simulation device for a degradable vascular stent, which realizes the dynamic action of the degradation liquid on the stent, but still cannot effectively simulate the one-way and pulsatile flushing action of blood. In addition, the device can only degrade a single stent, lacks a same-condition control, and is not convenient for continuous observation of the degradation behavior. The patent with publication number CN115356255A discloses a degradable vascular stent material corrosion experimental device, which realizes the simulation of dynamic blood flow, but the placing part in the device does not effectively position the stent, and lacks the simulation of the radial action of the blood vessel wall on the stent. The patent with publication number CN107974406A discloses a bioreactor for testing the degradation and fatigue performance of a vascular stent and a testing method thereof, which also lacks the simulation of the radial action of the blood vessel wall on the stent. SUMMARY

[0004] To solve the above technical problems, the present application provides an experimental device for simulating in vitro degradation of a cardiovascular stent, which can simultaneously simulate the periodic action of the blood vessel wall and the blood pulsation on the cardiovascular stent, realize real-time simulation of the stent degradation environment, and improve the accuracy of the experimental results.

[0005] To achieve the above-mentioned purposes, the present application provides the following solutions:

[0006] The application provides an experimental device for in-vitro simulation degradation of cardiovascular stents, which comprises a box, a water bath mechanism, a temperature controller, a heating component, a temperature measuring component, a degradation mechanism, a deposition mechanism, a pulsatile pump and a driving mechanism, the water bath mechanism comprises a water bath box and an upper support plate, the upper and lower ends of the water bath box are both open structures, the degradation mechanism comprises a shunt component, a loading connecting plate, a sliding block, a collection component and a plurality of degradation functional assemblies, the driving mechanism is connected with the bottom of the sliding block, the sliding block is slidingly installed in the box, the upper part of the sliding block is provided with a groove, the loading connecting plate is arranged on the upper part of the sliding block, the collection component is arranged on the lower part of the loading connecting plate, the lower end of the water bath box is arranged on the loading connecting plate, the temperature controller is arranged on the upper part of the box, and the heating component and the temperature measuring component are both arranged in the water bath box and electrically connected with the temperature controller; the upper support plate is arranged on one side of the temperature controller and above the water bath box, there is a gap between the upper support plate and the top of the water bath box, and the shunt component is arranged on the upper support plate; the degradation functional assembly comprises a simulation blood vessel and two connectors, the upper and lower ends of the simulation blood vessel are detachably installed on the shunt component and the loading connecting plate through the two connectors respectively; the pulsatile pump comprises a pump body and a piston push rod, one side of the pump body is provided with an opening, the piston push rod is slidingly installed in the pump body through the opening, one side of the piston push rod is connected with the driving mechanism, the driving mechanism is used for driving the sliding block and the piston push rod to synchronously perform periodic reciprocating motion, and the two ends of the pump body are respectively provided with a liquid inlet and a liquid outlet; the lower end of the collection component is connected with the inlet of the deposition mechanism through a first connecting pipe, the outlet of the deposition mechanism is connected with the liquid inlet through a second connecting pipe, and the liquid outlet is connected with the top of the shunt component through a third connecting pipe; unidirectional valves are arranged on the second connecting pipe and the third connecting pipe.

[0007] Preferably, the shunt component comprises an upper end cover and a shunt plate, the upper end cover is fixedly covered on the upper part of the shunt plate, one end of the third connecting pipe is connected with the top of the upper end cover, the upper support plate is provided with a through hole, the upper end cover is fixed in the through hole, and a plurality of mounting holes for mounting the connectors are arranged on the shunt plate and the loading connecting plate.

[0008] Preferably, the joint comprises an inner tube, an outer tube, a stop ring, a first spring, an adjusting block, a locking nut and a plurality of positioning balls, one end of the inner tube is provided with a polygonal edge plate, an outer wall of the inner tube is provided with external threads, the mounting hole comprises a polygonal hole and a circular hole connected in sequence, the polygonal edge plate is arranged in the polygonal hole, and the inner tube is arranged to extend to the outside through the circular hole, and the locking nut is arranged on the inner tube; one end of the outer tube is provided with an annular plate, the adjusting block, the first spring and the stop ring are sequentially sleeved on the outer tube, the stop ring is threadedly mounted on the outer tube, the adjusting block is located between the annular plate and the first spring, a wedge-shaped cavity is formed in the adjusting block, a plurality of positioning holes are arranged on the outer tube in the circumferential direction, an annular positioning groove is arranged on the outer wall of the inner tube, one end of the outer tube can be sleeved outside the inner tube, the positioning balls are arranged in the wedge-shaped cavity, each positioning ball can be arranged in one positioning hole and the annular positioning groove, and the other end of the outer tube can be sleeved outside the simulated blood vessel and connected through a clamp.

[0009] Preferably, a first annular groove is arranged on the outer wall of the end of the inner tube away from the polygonal edge plate, and a first sealing ring is arranged in the first annular groove, and the first sealing ring is located between the inner tube and the outer tube.

[0010] Preferably, an annular protrusion is arranged inside the simulated blood vessel, and the annular protrusion is used for limiting the lower end of the cardiovascular stent.

[0011] Preferably, one side of the water bath box is provided with an operation port, a side end cover is arranged on the operation port, the temperature measuring component is arranged on the inner side wall of the water bath box, the heating component is a heating pipeline, the lower end of the heating pipeline is located in the water bath box and forms an annular heating ring, the upper end of the heating pipeline extends to the outside of the water bath box and is fixed on a temperature controller, and the heating pipeline is electrically connected with the temperature controller.

[0012] Preferably, the pump body comprises a piston cylinder and a piston cover plate, the piston cylinder is fixed on the box body, the lower end and the upper end of the piston cylinder are respectively provided with the liquid inlet and the liquid outlet, one side of the piston cylinder is provided with the piston cover plate, and the other side of the piston cylinder is slidably provided with the piston push rod, a second annular groove is arranged on the outer wall of the piston push rod, a second sealing ring is arranged in the second annular groove, and the second sealing ring is located between the piston push rod and the piston cylinder.

[0013] Preferably, the deposition mechanism comprises a deposition tank, a filter screen, a pH display instrument, a probe, a liquid discharge pipe and a liquid discharge valve, the deposition tank is fixed to one side of the tank body, one end of the first connecting pipe is connected with the inlet of the deposition tank, one end of the second connecting pipe is connected with the outlet of the deposition tank, the filter screen is arranged at the outlet of the deposition tank, the liquid discharge pipe is arranged at the lower part of one side of the deposition tank, the liquid discharge valve is arranged on the liquid discharge pipe, the pH display instrument is arranged at the top of the deposition tank, the lower end of the probe extends into the deposition tank, and the probe is electrically connected with the pH display instrument.

[0014] Preferably, the driving mechanism comprises a driving assembly, a first crank connecting rod assembly and a second crank connecting rod assembly, the first power output shaft of the driving assembly is connected with the bottom of the sliding block through the first crank connecting rod assembly, and the second power output shaft of the driving assembly is connected with one side of the piston push rod through the second crank connecting rod assembly.

[0015] Preferably, the driving assembly comprises a driving motor and a transmission gear set, the driving motor is fixed in the tank body, the power output shaft of the driving motor is connected with the power input end of the transmission gear set, the transmission gear set comprises the first power output shaft and the second power output shaft, the first crank connecting rod assembly comprises a first crank, a first connecting rod and a first pin shaft, the first crank is fixed on the first power output shaft, the first pin shaft is fixed on the side of the first crank away from the first power output shaft, the central axis of the first pin shaft is parallel to the central axis of the first power output shaft, one end of the first connecting rod is rotatably sleeved on the first pin shaft, and the other end of the first connecting rod is hingedly connected with the bottom of the sliding block, and the second crank connecting rod assembly comprises a second crank, a second connecting rod and a second pin shaft, the second crank is fixed on the second power output shaft, the second pin shaft is fixed on the side of the second crank away from the second power output shaft, the central axis of the second pin shaft is parallel to the central axis of the second power output shaft, one end of the second connecting rod is rotatably sleeved on the second pin shaft, and the other end of the second connecting rod is hingedly connected with one side of the piston push rod.

[0016] The present application has the following technical effects relative to the prior art:

[0017] The experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the application comprises a box body, a water bath mechanism, a temperature controller, a heating component, a temperature measuring component, a degradation mechanism, a deposition mechanism, a pulsating pump and a driving mechanism, the degradation mechanism comprises a shunt component, a loading connecting plate, a sliding block, a collection component and a plurality of degradation functional assemblies, the pulsating pump comprises a pump body and a piston push rod, one side of the pump body is provided with an opening, the piston push rod is slidingly installed in the pump body through the opening, the driving mechanism is connected with one side of the piston push rod, and the driving mechanism is used for driving the sliding block and the piston push rod to synchronously perform periodic reciprocating motion; the sliding block is driven to make the simulated blood vessel periodically contract and expand, so as to simulate the radial action of the blood vessel wall on the cardiovascular stent; and the piston push rod is driven to enable the pulsating pump to simulate the erosion of blood pulsation. The experimental device can synchronously simulate the periodic action of the blood vessel wall and blood pulsation on the cardiovascular stent, realizes real-time simulation of the stent degradation environment, and improves the accuracy of experimental results. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0019] Figure 1 The structural schematic diagram of the experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the present application is shown in the figure.

[0020] Figure 2 The structural schematic diagram of the driving mechanism and the degradation mechanism in the experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the present application is shown in the figure.

[0021] Figure 3 The structural schematic diagram of the degradation mechanism in the experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the present application is shown in the figure.

[0022] Figure 4 The installation schematic diagram of the shunt component and the degradation functional assembly in the experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the present application is shown in the figure.

[0023] Figure 5 The structural schematic diagram of the shunt component in the experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the present application is shown in the figure.

[0024] Figure 6 The structural schematic diagram of the degradation functional assembly in the experimental device for simulating in-vitro degradation of a cardiovascular stent provided by the present application is shown in the figure.

[0025] Figure 7A schematic structural diagram of a pulsating pump in an experimental device for simulating in vitro degradation of a cardiovascular stent provided by the present invention;

[0026] Figure 8 A schematic diagram of the structure of a one-way valve in an experimental device for simulating in vitro degradation of a cardiovascular stent provided by the present invention;

[0027] Figure 9 A schematic structural diagram of a water bath mechanism in an experimental device for simulating in vitro degradation of a cardiovascular stent provided by the present invention;

[0028] Figure 10 A schematic structural diagram of a deposition mechanism in an experimental device for simulating in vitro degradation of a cardiovascular stent provided by the present invention;

[0029] Figure 11 This is a schematic diagram of the structure of the filter screen in the experimental device for simulating the degradation of cardiovascular stents in vitro provided by the present invention.

[0030] Explanation of the accompanying symbols: 100, experimental device for simulating in vitro degradation of cardiovascular stents; 1, box body; 2, temperature controller; 3, water bath; 4, upper support plate; 5, diverter component; 51, diverter plate; 52, upper end cover; 6, side end cover; 7, deposition mechanism; 71, deposition box; 72, pH display; 73, probe; 74, drain pipe; 75, drain valve; 76, filter screen; 8, pulsating pump; 81, piston cylinder; 82, piston cover plate; 83, piston push rod; 84, second sealing ring; 9, one-way valve; 91, hollow valve body; 92, hollow support block; 93, stop block; 94, second spring; 95, movable block; 10, first connecting pipe; 11, second connecting pipe; 12, third connecting pipe; 1 3. Slider; 14. Loading connecting plate; 15. Collection component; 16. Degradation functional component; 161. Simulated blood vessel; 162. Annular protrusion; 163. Inner tube; 164. Polygonal edge plate; 165. Locking nut; 166. Outer tube; 167. Annular plate; 168. Adjustment block; 169. First spring; 1610. Retaining ring; 1611. Positioning ball; 1612. First sealing ring; 17. Heating component; 18. Drive motor; 19. Transmission gear set; 20. First crank; 21. First connecting rod; 22. Second crank; 23. Second pin; 24. Second connecting rod; 25. Positioning block; 26. Mounting hole; 261. Polygonal hole; 262. Circular hole; 27. Cardiovascular stent. DETAILED DESCRIPTION

[0031] Clearly, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts, fall within the protection scope of the present application.

[0032] The purpose of the present application is to provide an experimental device for in vitro simulation of degradation of cardiovascular stents, which can simulate the periodic effect of blood vessel wall and blood pulsation on cardiovascular stents synchronously, realize real-time simulation of stent degradation environment, and improve the accuracy of experimental results.

[0033] In order to make the above-mentioned purposes, characteristics and advantages of the present application more apparent and easy to understand, the present application will be further described in detail below with reference to the drawings and specific embodiments.

[0034] As Figures 1-11As shown, this embodiment provides an experimental device 100 for simulating the degradation of a cardiovascular stent in vitro, comprising a housing 1, a water bath mechanism, a temperature controller 2, a heating component 17, a temperature measuring component, a degradation mechanism, a deposition mechanism 7, a pulsating pump 8, and a driving mechanism. The water bath mechanism comprises a water bath box 3 and an upper support plate 4. Both the upper and lower ends of the water bath box 3 are open structures. The degradation mechanism comprises a diversion component 5, a loading connecting plate 14, a slider 13, a collecting component 15, and a plurality of degradation functional components 16. The driving mechanism and the bottom of the slider 13 are connected. The slider 13 is slidably installed in the box body 1, the upper part of the slider 13 is provided with a groove, the loading connecting plate 14 is provided on the upper part of the slider 13, the collecting component 15 is provided on the lower part of the loading connecting plate 14, the lower end of the water bath 3 is provided on the loading connecting plate 14, the thermostat 2 is provided on the upper part of the box body 1, the heating component 17 and the temperature measuring component are both provided in the water bath 3 and are electrically connected to the thermostat 2; the upper support plate 4 is provided on one side of the thermostat 2 and is located above the water bath 3, and the upper support plate 4 is connected to the top of the water bath 3. There is a gap between them, and the diversion component 5 is arranged on the upper support plate 4; the degradation functional component 16 includes a simulated blood vessel 161 and two joints. The upper and lower ends of the simulated blood vessel 161 can be detachably installed on the diversion component 5 and the loading connection plate 14 through two joints respectively, and the simulated blood vessel 161 is used to place a cardiovascular stent 27; the pulsating pump 8 includes a pump body and a piston push rod 83, one side of the pump body is provided with an opening, the piston push rod 83 is slidably installed in the pump body through the opening, the driving mechanism is connected to one side of the piston push rod 83, the driving mechanism is used to drive the slider 13 and the piston push rod 83 to perform periodic reciprocating motion synchronously, and the two ends of the pump body are respectively provided with a liquid inlet and a liquid outlet; the lower end of the collecting component 15 is connected to the inlet of the deposition mechanism 7 through the first connecting pipe 10, and the outlet of the deposition mechanism 7 is connected to the liquid inlet through the second connecting pipe 11. A filter screen 76 is provided at the outlet of the deposition mechanism 7, and the liquid outlet is connected to the top of the diversion component 5 through the third connecting pipe 12. Both the second connecting pipe 11 and the third connecting pipe 12 are provided with a one-way valve 9.

[0035] The upper end of the simulated blood vessel 161 is fixed to the shunt component 5 by a joint in this embodiment, that is, the position of the upper end of the simulated blood vessel 161 is fixed, and the lower end is fixed to the loading connecting plate 14 by a joint. When the driving mechanism drives the slider 13 to move vertically along the box body 1, the slider 13 drives the loading connecting plate 14 and the simulated blood vessel 161 of the loading connecting plate 14 to move vertically, drives the simulated blood vessel 161 to contract and expand periodically, and further simulates the radial action of the blood vessel wall on the cardiovascular stent 27. The driving mechanism can also drive the piston push rod 83 to move reciprocally along the pump body. When the piston push rod 83 moves to one side, the space in the pump body becomes larger to form a pressure difference, and the degradation liquid flows into the second connecting pipe 11 from the one-way valve 9. When the piston push rod 83 moves to the other side, the degradation liquid is pushed out from the third connecting pipe 12 to the shunt component 5, and the periodic reciprocating movement of the piston push rod 83 realizes the simulation of the pulsation of the heart.

[0036] Since the action site of the cardiovascular stent 27 is in the heart, the periodic movement of the heart has a significant effect on the service environment of the coronary stent. When the heart contracts to pump blood, the coronary artery contracts synchronously under the action of the myocardium, and the blood flow decreases. When the heart relaxes, the coronary artery expands, and the blood flows back. Therefore, the simulation of the degradation environment of the cardiovascular stent 27 in this embodiment combines the radial action of the blood vessel wall and the pulsating erosion of the blood, and realizes periodic synchronization. The experimental device in this embodiment can simulate the periodic action of the blood vessel wall and the blood pulsation on the cardiovascular stent 27 synchronously, and further simulate the comprehensive action of the heart contraction and expansion on the cardiovascular stent 27, realize the real-time simulation of the stent degradation environment, and improve the accuracy of the experimental results.

[0037] As Figure 4 and Figure 5As shown, the shunt component 5 includes an upper end cover 52 and a shunt plate 51, the upper end cover 52 is fixedly covered on the upper part of the shunt plate 51, one end of the third connecting pipe 12 is connected with the top of the upper end cover 52, the upper support plate 4 is provided with a through hole, the upper end cover 52 is fixed in the through hole, the shunt plate 51 and the loading connecting plate 14 are both provided with a plurality of mounting holes 26 for mounting joints, the collection component 15 in the embodiment is funnel-shaped, the shunt plate 51 is a circular plate and the mounting holes 26 on the shunt plate 51 are uniformly arranged in the circumferential direction, the same sample flow is ensured as much as possible, a consistent degradation environment is provided for the multiple cardiovascular stents 27, the test results of the samples are comparable, and the test efficiency is improved. During the experiment, the degradation liquid flows in through the third connecting pipe 12, is divided into multiple streams through the shunt plate 51 and is respectively merged into multiple simulation blood vessels 161, the degradation liquid periodically flushes and corrodes the simulation blood vessels 161 to simulate the effect of the simulation blood vessels 161 on the cardiovascular stents 27, then the degradation liquid is merged through the funnel-shaped collection component 15 and flows back to the deposition mechanism 7 through the first connecting pipe 10. The slider 13 is provided with two vertical positioning blocks 25 on both sides, a guide groove is formed between the two positioning blocks 25, the guide groove is slidingly installed on the vertical guide rail on the inner wall of the box body 1, the slider 13 moves up and down along the guide rail on the box body 1 under the action of the driving mechanism, thereby driving the simulation blood vessels 161 to periodically contract and expand to simulate the radial effect of the simulation blood vessel wall on the cardiovascular stents 27. Due to the movement needs of the device, the first connecting pipe 10 at the collection component 15 adopts a hose and leaves a certain length allowance.

[0038] The inside of the simulation blood vessel 161 is provided with an annular protrusion 162, the annular protrusion 162 is used for limiting the lower end of the cardiovascular stent 27, thereby preventing the cardiovascular stent 27 from sliding downward.

[0039] The joints in the embodiment are used for guiding the degradation liquid and transmitting the load, for example, Figure 6As shown, the joint comprises an inner tube 163, an outer tube 166, a retaining ring 1610, a first spring 169, an adjusting block 168, a locking nut 165, and a plurality of positioning balls 1611. One end of the inner tube 163 is provided with a polygonal edge plate 164, and an outer wall of the inner tube 163 is provided with external threads. The mounting hole 26 comprises a polygonal hole 261 and a circular hole 262 connected in sequence. The polygonal edge plate 164 is arranged in the polygonal hole 261, and the inner tube 163 extends to the outside through the circular hole 262. The locking nut 165 is arranged on the inner tube 163. The polygonal edge plate 164 cooperates with the polygonal hole 261 to prevent the inner tube 163 from rotating. The locking nut 165 is screwed to contact the shunt plate 51 or the loading connecting plate 14. At this time, the inner tube 163 is positioned in the vertical direction under the action of the locking nut 165 and the polygonal edge plate 164, and the inner tube 163 is fixed to the shunt plate 51 or the loading connecting plate 14. One end of the outer tube 166 is provided with an annular plate 167. The outer tube 166 is sequentially sleeved with the adjusting block 168, the first spring 169, and the retaining ring 1610. An outer wall of the outer tube 166 is provided with external threads. The retaining ring 1610 is threadedly mounted on the outer tube 166. The adjusting block 168 is located between the annular plate 167 and the first spring 169. The retaining ring 1610 is used for limiting the lower end of the first spring 169. The adjusting block 168 can slide relative to the outer tube 166. A wedge-shaped cavity is formed in the adjusting block 168. A plurality of positioning holes are circumferentially arranged on the outer tube 166. An annular positioning groove is arranged on an outer wall of the inner tube 163. One end of the outer tube 166 can be sleeved outside the inner tube 163. The positioning balls 1611 are arranged in the wedge-shaped cavity. The end of the wedge-shaped cavity away from the first spring 169 is a large-end. Each positioning ball 1611 can be arranged in a positioning hole and an annular positioning groove. The other end of the outer tube 166 can be sleeved outside the simulated blood vessel 161 and connected by a clamp. Taking the joint located at the upper part of the simulated blood vessel 161 as an example, during the experiment, the adjusting block 168 is moved downward to move the positioning balls 1611 radially outward to release the limitation. At this time, the outer tube 166 and the inner tube 163 can move relatively. After being loosened, the adjusting block 168 is moved upward again under the action of the first spring 169 to press the positioning balls 1611 tightly, so that the outer tube 166 and the inner tube 163 are fixed relatively, and the locking of the joint is realized. In this embodiment, the joint with positioning ball limiting is adopted. The quick connection can be realized by moving the adjusting block 168, the clamping consistency is guaranteed, and the clamping in a narrow space can be realized.

[0040] In order to realize the sealing between the inner tube 163 and the outer tube 166, an outer wall of one end of the inner tube 163 away from the polygonal edge plate 164 is provided with a first annular groove. The annular positioning groove is located between the polygonal edge plate 164 and the first annular groove. A first sealing ring 1612 is arranged in the first annular groove. The first sealing ring 1612 is located between the inner tube 163 and the outer tube 166. The polygonal edge plate 164 in this embodiment is a hexagonal edge plate, and the polygonal hole 261 is a hexagonal hole.

[0041] As Figure 9 shown, the water bath box 3 is provided with an operating port on one side, and a side end cover 6 is installed on the operating port for sealing the operating port. The operating port is convenient for installing the components inside the water bath box 3. The temperature measuring component is arranged on the inner side wall of the water bath box 3. The heating component 17 is a heating pipe. The lower end of the heating pipe is located in the water bath box 3 and forms an annular heating ring. The upper end of the heating pipe extends to the outside of the water bath box 3 and is fixed to the temperature controller 2. The heating pipe is electrically connected to the temperature controller 2. The water bath box 3 contains water to soak the plurality of degradation functional components 16. The annular heating ring uniformly heats the plurality of degradation functional components 16. The temperature adjustment is realized by the electrical connection between the heating component 17, the temperature measuring component and the temperature controller 2. The temperature can be adjusted to adapt to the degradation experiment with different speed requirements. The degradation can be accelerated by increasing the water bath temperature during the experiment.

[0042] As Figure 7 shown, the pump body includes a piston cylinder body 81 and a piston cover plate 82. The piston cylinder body 81 is fixed to the box body 1. The lower end and the upper end of the piston cylinder body 81 are respectively provided with a liquid inlet and a liquid outlet. The piston cylinder body 81 is provided with the piston cover plate 82 on one side. The piston cylinder body 81 is slidably installed with a piston push rod 83 on the other side. The piston push rod 83 is provided with a second annular groove on the outer wall. The second annular groove is provided with a second sealing ring 84. The second sealing ring 84 is located between the piston push rod 83 and the piston cylinder body 81. The one-way valves 9 on the second connecting pipe 11 and the third connecting pipe 12 are arranged at one end close to the piston cylinder body 81. Specifically, the one-way valve 9 arranged on the second connecting pipe 11 is located at the lower end of the liquid inlet. The one-way valve 9 arranged on the third connecting pipe 12 is located at the upper end of the liquid outlet. The piston push rod 83 is driven by the driving mechanism to reciprocate. When the piston push rod 83 moves away from the piston cover plate 82, the internal space of the piston cylinder body 81 becomes larger to form a pressure difference. The degradation liquid flows into the lower end of the one-way valve 9. When the piston push rod 83 moves close to the piston cover plate 82, the degradation liquid is pushed out from the upper end of the one-way valve 9. The periodic reciprocating motion of the piston push rod 83 realizes the simulation of the heart pulsatile blood pumping.

[0043] As Figure 8As shown, the one-way valve 9 includes a hollow valve body 91, a hollow support block 92, a stop block 93, a movable block 95 and a second spring 94, the hollow valve body 91 is vertically installed on the second connecting pipe 11 or the third connecting pipe 12, the hollow support block 92 and the stop block 93 are sequentially arranged in the hollow valve body 91 from top to bottom, the second spring 94 is fixed below the hollow support block 92, the movable block 95 is fixed below the second spring 94, the movable block 95 is a reverse tapered block, and the stop block 93 is provided with a flow-through hole matched with the structure of the stop block 93. When the degradation liquid flows from the lower side, it will push the movable block 95 to move upwards, so that it leaves the stop block 93 to form a passage; when the degradation liquid flows from the upper side, it will push the movable block 95 to adhere to the stop block 93 to close the passage, thereby realizing the one-way flow of the liquid flow.

[0044] During the degradation process of the cardiovascular stent 27, unintended insoluble microparticles may enter the blood circulation, thereby causing the occurrence of thrombosis and the like. Similarly, under the extrusion of the simulated blood vessel wall and the erosion of the degradation liquid, a large number of micro-debris may be generated, and these debris may deposit and block important pipelines. Therefore, in the embodiment, a deposition mechanism 7 is arranged to make the debris out of circulation. As shown in Figure 10 and Figure 11 As shown, the deposition mechanism 7 includes a deposition tank 71, a filter screen 76, a pH display instrument 72, a probe 73, a drainage pipe 74 and a drainage valve 75, the deposition tank 71 is fixed to one side of the tank body 1, one end of the first connecting pipe 10 is connected with the inlet of the deposition tank 71, one end of the second connecting pipe 11 is connected with the outlet of the deposition tank 71, the inlet and the outlet of the deposition tank 71 are respectively arranged on the two sides of the upper part of the deposition tank 71, the filter screen 76 is arranged at the outlet of the deposition tank 71, the deposition tank 71 mainly settles the suspended particles through the action of gravity, and secondary separation is performed through the filter screen 76; the lower part of one side of the deposition tank 71 is provided with the drainage pipe 74, the drainage valve 75 is arranged on the drainage pipe 74, and the drainage valve 75 is used for discharging the deposits and the degradation waste liquid for analysis; the pH display instrument 72 is arranged on the top of the deposition tank 71, the lower end of the probe 73 extends into the deposition tank 71, and the probe 73 is electrically connected with the pH display instrument 72. pH is an important index of the reaction degradation process, pH monitoring is performed through the probe 73, and the measured pH value is displayed on the pH display instrument 72.

[0045] The driving mechanism includes a driving assembly, a first crank connecting rod assembly and a second crank connecting rod assembly, the first power output shaft of the driving assembly is connected with the bottom of the sliding block 13 through the first crank connecting rod assembly, the sliding block 13 is driven to reciprocate along the guide rail on the tank body 1 through the first crank connecting rod assembly, and the second power output shaft of the driving assembly is connected with one side of the piston push rod 83 through the second crank connecting rod assembly, and the piston push rod 83 is driven to reciprocate along the piston cylinder body 81 through the second crank connecting rod assembly.

[0046] The driving assembly comprises a driving motor 18 fixed in the box body 1 and a transmission gear set 19, a power output shaft of the driving motor 18 is connected with a power input end of the transmission gear set 19, the transmission gear set 19 comprises a first power output shaft and a second power output shaft, the first power output shaft is fixedly sleeved in the center of the first output gear, the second power output shaft is fixedly sleeved in the center of the second output gear, the first power output shaft and the second power output shaft are both rotationally installed on the box body 1, and meanwhile, gear shafts of intermediate transmission gears in the transmission gear set 19 are all rotationally installed on the box body 1; the first crank connecting rod assembly comprises a first crank 20, a first connecting rod 21 and a first pin shaft, the first crank 20 is fixed on the first power output shaft, the first pin shaft is fixed on a side of the first crank 20 away from the first power output shaft, a central axis of the first pin shaft is parallel to a central axis of the first power output shaft, that is, the central axis of the first pin shaft and the central axis of the first power output shaft are arranged in a non-collinear manner, one end of the first connecting rod 21 is rotationally sleeved on the first pin shaft, and the other end of the first connecting rod 21 is hingedly connected to the bottom of the sliding block 13; the second crank connecting rod assembly comprises a second crank 22, a second connecting rod 24 and a second pin shaft 23, the second crank 22 is fixed on the second power output shaft, the second pin shaft 23 is fixed on a side of the second crank 22 away from the second power output shaft, a central axis of the second pin shaft 23 is parallel to a central axis of the second power output shaft, that is, the central axis of the second pin shaft 23 and the central axis of the second power output shaft are arranged in a non-collinear manner, one end of the second connecting rod 24 is rotationally sleeved on the second pin shaft 23, and the other end of the second connecting rod 24 is hingedly connected to one side of the piston push rod 83. During the experiment, the driving motor 18 drives the terminal crank sliding block mechanism through the gear transmission set, the first output gear and the second output gear are adjusted to rotate at the same speed through the gear transmission ratio, the initial positions of the first crank 20 and the second crank 22 are adjusted, and then the motion periods of the first crank connecting rod assembly and the second crank connecting rod assembly are synchronized, and the motion amplitude is adjusted by changing the length of the crank connecting rod.

[0047] The specific use process is as follows: a plurality of cardiovascular stents 27 are respectively arranged in a plurality of simulated blood vessels 161, the upper and lower ends of the simulated blood vessels 161 are respectively installed on the shunt plate 51 and the loading connecting plate 14 through joints, the third connecting pipe 12 is taken off from the upper end cover 52, the degradation solution is injected through the inlet at the top of the upper end cover 52, then the third connecting pipe 12 is reinstalled on the upper end cover 52, water is injected in the water bath box 3 and heated to a required temperature, after the temperature is stable, the driving motor 18 is started, the degradation solution is circulated and pulsated, and the simulated blood vessels 161 load the cardiovascular stents 27 in the radial direction, the pH display instrument 72 is used to observe the pH change in the degradation process and timely adjustment is made, after the degradation experiment is completed, the drainage valve is opened to drain the water bath water and the degradation solution from the drainage pipe 74, and the cardiovascular stents 27 are taken out for analysis.

[0048] The principles and implementation manners of the present application are described in the specification by using specific examples, and the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation manners and application ranges will be changed. In conclusion, the content of the specification should not be understood as a limitation of the present application.

Claims

1. An experimental device for in-vitro simulation of degradation of cardiovascular stents, characterized by, It includes a box body, a water bath mechanism, a temperature controller, a heating component, a temperature measuring component, a degradation mechanism, a deposition mechanism, a pulsating pump and a driving mechanism. The water bath mechanism includes a water bath box and an upper support plate. The upper and lower ends of the water bath box are open structures. The degradation mechanism includes a diversion component, a loading connecting plate, a slider, a collecting component and multiple degradation functional components. The driving mechanism is connected to the bottom of the slider. The slider is slidably installed in the box body. The upper part of the slider is provided with a groove. The loading connecting plate is provided on the upper part of the slider. The collecting component is provided at the lower part of the loading connecting plate. The lower end of the water bath box is provided on the loading connecting plate. The thermostat is arranged on the upper part of the box body, the heating component and the temperature measuring component are both arranged in the water bath and are electrically connected to the thermostat; the upper support plate is arranged on one side of the thermostat and is located above the water bath, there is a gap between the upper support plate and the top of the water bath, and the diversion component is arranged on the upper support plate; the degradation function component includes a simulated blood vessel and two joints, the upper and lower ends of the simulated blood vessel are respectively detachably mounted on the diversion component and the loading connection plate through two joints; the pulsating pump includes a pump body and a piston push rod, one side of the pump body is provided with an opening, and the piston push rod slides through the opening The cam is connected to the pump body, and the driving mechanism is connected to one side of the piston push rod. The driving mechanism is used to drive the slider and the piston push rod to synchronously perform periodic reciprocating motion. The two ends of the pump body are respectively provided with a liquid inlet and a liquid outlet; the lower end of the collecting component is connected to the inlet of the sedimentation mechanism through a first connecting pipe, the outlet of the sedimentation mechanism is connected to the liquid inlet through a second connecting pipe, and the liquid outlet is connected to the top of the diverter component through a third connecting pipe, and the second connecting pipe and the third connecting pipe are both provided with a one-way valve; the diverter component includes an upper end cover and a diverter plate, the upper end cover fixing cover is arranged on the upper part of the diverter plate, and the first One end of the three-connecting pipe is connected to the top of the upper end cover, the upper support plate is provided with a through hole, the upper end cover is fixed in the through hole, and the diverter plate and the loading connection plate are both provided with a plurality of mounting holes for mounting the joint; the joint comprises an inner tube, an outer tube, a retaining ring, a first spring, an adjusting block, a locking nut and a plurality of positioning balls, one end of the inner tube is provided with a polygonal edge plate, the outer wall of the inner tube is provided with an external thread, the mounting hole comprises a polygonal hole and a circular hole connected in sequence, the polygonal edge plate is used to be arranged in the polygonal hole, and the inner tube is used to pass through the circular hole to extend to the outside, and a locking nut is provided on the inner tube;One end of the outer tube is provided with an annular plate, the outer tube is sequentially sleeved with an adjusting block, a first spring and a stop ring, the stop ring is threadedly mounted on the outer tube, the adjusting block is located between the annular plate and the first spring, a wedge-shaped cavity is formed in the adjusting block, a plurality of positioning holes are circumferentially arranged on the outer tube, an annular positioning groove is arranged on the outer wall of the inner tube, one end of the outer tube can be sleeved outside the inner tube, the positioning balls are arranged in the wedge-shaped cavities, each positioning ball can be arranged in one positioning hole and the annular positioning groove, the other end of the outer tube can be sleeved outside the simulated blood vessel and connected through a clamp; the deposition mechanism comprises a deposition tank, a filter screen, a pH display instrument, a probe, a drainage pipe and a drainage valve, the deposition tank is fixed to one side of the outer side of the box, one end of the first connecting pipe is connected with the inlet of the deposition tank, one end of the second connecting pipe is connected with the outlet of the deposition tank, the filter screen is arranged at the outlet of the deposition tank, the lower part of one side of the deposition tank is provided with the drainage pipe, the drainage valve is arranged on the drainage pipe, the pH display instrument is arranged on the top of the deposition tank, the lower end of the probe extends into the deposition tank, and the probe is electrically connected with the pH display instrument; the driving mechanism comprises a driving assembly, a first crank connecting rod assembly and a second crank connecting rod assembly, the first power output shaft of the driving assembly is connected with the bottom of the sliding block through the first crank connecting rod assembly, and the second power output shaft of the driving assembly is connected with one side of the piston push rod through the second crank connecting rod assembly.

2. The experimental setup for in-vitro simulation of degradation of cardiovascular stents as claimed in claim 1 wherein, The outer wall of one end of the inner tube away from the polygonal edge plate is provided with a first annular groove, and a first sealing ring is arranged in the first annular groove and located between the inner tube and the outer tube.

3. The experimental setup for in-vitro simulation of degradation of cardiovascular stents as claimed in claim 1 wherein, The inside of the simulation blood vessel is provided with an annular protrusion for limiting the lower end of the cardiovascular stent.

4. The experimental setup for in-vitro simulation of degradation of cardiovascular stents as claimed in claim 1 wherein, One side of the water bath box is provided with an operation port for installing a side end cover, the temperature measuring component is arranged on the inner side wall of the water bath box, the heating component is a heating pipe, the lower end of the heating pipe is located in the water bath box and forms an annular heating ring, the upper end of the heating pipe extends to the outside of the water bath box and is fixed to the temperature controller, and the heating pipe is electrically connected to the temperature controller.

5. The experimental setup for in-vitro simulation of degradation of cardiovascular stents as claimed in claim 1 wherein, The pump body includes a piston cylinder and a piston cover plate, the piston cylinder is fixed to the box body, the lower end and the upper end of the piston cylinder are respectively provided with the liquid inlet and the liquid outlet, one side of the piston cylinder is provided with the piston cover plate, and the other side of the piston cylinder is slidably provided with the piston push rod, the outer wall of the piston push rod is provided with a second annular groove, a second sealing ring is arranged in the second annular groove and located between the piston push rod and the piston cylinder.

6. The experimental setup for in-vitro simulation of degradation of cardiovascular stents as claimed in claim 1 wherein, The driving assembly includes a driving motor and a transmission gear set, the driving motor is fixed in the box body, the power output shaft of the driving motor is connected with the power input end of the transmission gear set, and the transmission gear set includes the first power output shaft and the second power output shaft; the first crank connecting rod assembly includes a first crank, a first connecting rod and a first pin shaft, the first crank is fixed on the first power output shaft, the first pin shaft is fixed on one side of the first crank away from the first power output shaft, the central axis of the first pin shaft is parallel to the central axis of the first power output shaft, one end of the first connecting rod is rotatably sleeved on the first pin shaft, and the other end of the first connecting rod is hingedly connected to the bottom of the sliding block; the second crank connecting rod assembly includes a second crank, a second connecting rod and a second pin shaft, the second crank is fixed on the second power output shaft, the second pin shaft is fixed on one side of the second crank away from the second power output shaft, the central axis of the second pin shaft is parallel to the central axis of the second power output shaft, one end of the second connecting rod is rotatably sleeved on the second pin shaft, and the other end of the second connecting rod is hingedly connected to one side of the piston push rod.

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