CN110514376B

CN110514376B - Valve support capability test device

Info

Publication number: CN110514376B
Application number: CN201910688771.7A
Authority: CN
Inventors: 申祥; 鲁凯凯; 蒋佳宝; 朱洪飞
Original assignee: Jiangsu University
Current assignee: Jiangsu University
Priority date: 2019-07-29
Filing date: 2019-07-29
Publication date: 2021-02-12
Anticipated expiration: 2039-07-29
Also published as: CN110514376A

Abstract

The invention provides a valve stent performance testing device, which comprises a multifunctional test board, a liquid storage tank, a single chip microcomputer and a computer, wherein the liquid storage tank is arranged on the multifunctional test board; the multifunctional test bench comprises a first test bench I and a second test bench II, wherein the first test bench I can realize the strain and vibration frequency test, the cross-valve differential pressure test and the opening area test of the valve support, and the second test bench II can realize the durability test of the valve support; the first test bench I and the second test bench II can simultaneously test, so that the artificial valve stent can be dynamically tested in multiple performances at the same time, and can also be independently tested, and the use is convenient and flexible; the defect that the conventional test method is usually that one detection device can only complete the test of single performance is overcome, the application range is wide, and the universal adaptability is realized.

Description

Valve support capability test device

Technical Field

The invention belongs to the technical field of performance testing of medical equipment, and particularly relates to a valve stent performance testing device.

Background

At present, heart valve patients in China account for about 30% of heart patients, and a large number of patients need to perform heart valve replacement operation every year. The artificial heart valve is used as a heart implantation interventional medical appliance for treating heart valve diseases or defects, is firstly applied to clinic in 1960, and is a very important medical appliance in the field of cardiovascular treatment at present. Then, the mechanical valve, the biological tissue valve, the intervention valve and the like are performed. Although many heart valve stents have been very effective today, there is still a great gap in comparison to native heart valves. All prosthetic valves are hemodynamically abnormal compared to normal native valves. Therefore, the heart valve stent is used as a foreign object and is easy to have unexpected situations after being implanted into a human body. The heart valve stent with good performance can greatly relieve the pain of a patient and reduce the probability of secondary injury of the patient. The clinical heart valve stent performance mainly comprises: the method comprises the steps of strain and vibration frequency testing, cross-petal pressure difference testing, opening area testing and durability testing. For example, the trans-valve pressure difference of the mitral valve is an important index for evaluating mitral stenosis and calculating the mitral valve opening area, and the valve opening area greatly determines the clinical use effect.

At present, scholars at home and abroad put the center of gravity on the research heart valve stent, but the research on related test devices is little, most of the scholars aim at testing a certain single performance, and the application range is narrow, for example, the scholars are only suitable for testing the trans-valve pressure difference of a mechanical valve or the durability or the valve opening area of a balloon type valve stent. These factors can limit the technological development of the valve. Therefore, a comprehensive performance testing platform integrating multiple performance tests is urgently needed.

Disclosure of Invention

In view of the above technical problems, the invention provides a multifunctional performance testing device for a valve stent, which is a portable multifunctional performance testing device for a prosthetic valve stent, has a simple structure, is convenient to operate and implement, and can be applied to the performance testing of mainstream prosthetic valve stents in the existing market.

A valve support performance testing device comprises a multifunctional test board, a liquid storage tank, a power device, a single chip microcomputer and a computer;

the multifunctional test bench comprises a first test bench I, wherein the first test bench I comprises an upper cover plate, a differential pressure sensor, an image acquisition mechanism, a test base and a Wheatstone bridge circuit; the upper cover plate is provided with a first through hole, the test base is provided with a second through hole, and the first through hole corresponds to the second through hole in position and can be communicated with the second through hole; the second through hole can be used for placing a valve stent; the pressure difference sensor is used for detecting the pressure difference of the valve support and is connected with the data acquisition card; the image acquisition mechanism is used for acquiring an image of the valve stent; the Wheatstone bridge circuit is arranged on the test base and is connected with the data acquisition card;

the liquid storage tank is connected with the second through hole of the testing base through a first pipeline, and the first through hole of the upper cover plate is connected with the liquid storage tank through a second pipeline to form a loop;

the output end of the power device is connected with a first pipeline, liquid in the liquid storage tank is conveyed to the first test bench I, and the power device is connected with the single chip microcomputer;

and the computer is respectively connected with the differential pressure sensor, the image acquisition mechanism, the data acquisition card, the liquid storage tank and the single chip microcomputer.

In the above scheme, the multifunctional test bench further comprises a second test bench II;

the second test bench II comprises a sliding plate, a guide rail, an arc-shaped clamping plate, a spring and an electromagnetic coil; the guide rail is provided with a second groove, sliding plates which are symmetrically arranged are arranged on two sides of the second groove respectively, the sliding plates are connected with the guide rail in a sliding mode, arc-shaped clamping plates are arranged on the inner sides of the sliding plates respectively, and the arc-shaped clamping plates are symmetrically arranged on two sides of the second groove to form a circular ring shape; the two sides of the arc-shaped clamping plate are respectively provided with a spring, the two ends of the spring are respectively connected with the sliding plate, the electromagnetic coil is arranged near the spring, and the electromagnetic coil is connected with the single chip microcomputer.

In the scheme, a hydraulic switch, a first one-way valve, a buffer tank, a pressure sensor and a flow sensor are sequentially arranged on the first pipeline from the liquid storage tank to a second through hole of the test base, and the pressure sensor and the flow sensor are respectively connected with a data acquisition card; the output end of the power device is connected with the first pipeline and is positioned between the first one-way valve and the buffer tank;

and a second one-way valve and a deflation valve are sequentially arranged on the second pipeline from the first through hole of the upper cover plate to the liquid storage tank.

Further, a particle injector is also arranged on the first pipeline; the particle injector is located after the flow sensor.

Furthermore, an overflow valve is also arranged on the first pipeline; the overflow valve is positioned between the buffer tank and the pressure sensor.

Further, a pressure regulator is arranged on the second pipeline; the pressure regulator is positioned between the first through hole of the upper cover plate and the second one-way valve.

In the scheme, the power device comprises a servo motor, a coupler, a bearing, a ball screw, two push plates, a piston rod and a cavity;

the output end of the servo motor is connected with one end of the ball screw through a coupler; the other end of the ball screw is connected with the first push plate, and the two ends of the ball screw are respectively arranged in the bearings; the first push plate and the second push plate are connected through a connecting rod, one end of the piston rod is connected with the second push plate, and the other end of the piston rod extends into the cavity; the cavity is communicated with the first pipeline.

In the scheme, the liquid storage tank is provided with a temperature probe and a heater;

the temperature probe is connected with a data acquisition card, and the data acquisition card is connected with a computer; the heater is connected with the singlechip.

In the above scheme, a first groove is arranged in the second through hole of the test base; the first groove is used for placing a valve stent.

In the above scheme, the test base is further provided with a differential pressure sensor interface, and the differential pressure sensor interface is located below the second through hole; the upper cover plate is also provided with a third pipeline, and the third pipeline is positioned above the first through hole; the input end of the differential pressure sensor is connected with the differential pressure sensor interface, and the output end of the differential pressure sensor is connected with the third pipeline.

Compared with the prior art, the invention has the beneficial effects that: the multifunctional test bench can dynamically test the multifunctional performance of the artificial valve support, the first test bench I can realize the strain and vibration frequency test, the cross-valve pressure difference test and the opening area test of the valve support, and the second test bench II can realize the durability test of the valve support; the first test bench I and the second test bench II can simultaneously test, so that the artificial valve stent can be dynamically tested in multiple performances at the same time, and can also be independently tested, and the use is convenient and flexible; the multifunctional performance test device overcomes the defect that the conventional test method is usually that one detection device can only test single performance, has wide application range and universal adaptability, and is suitable for multifunctional performance tests of mechanical valves, biological valves, mitral valves, tricuspid valves, aortic valves and the like.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

FIG. 2 is a circuit diagram of a first testing station according to an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a multifunctional test stand according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a first testing station I of the apparatus according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a second testing station II of the apparatus according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a power plant in accordance with an embodiment of the present invention;

FIG. 7 is a schematic diagram of a Wheatstone bridge circuit according to an embodiment of the present invention, wherein (a) is a prosthetic mechanical valve and (b) is a bio-engineered valve.

Description of reference numerals:

1. a computer; 2. a temperature probe; 3. a heater; 4. a digital liquid storage tank; 5. a hydraulic switch; 6. a first check valve; 7. a buffer tank; 8. an overflow valve; 9. a pressure sensor; 10. a flow sensor; 11. a particle injector; 12. a power plant; 13. a multifunctional test bench; 14. a pressure regulator; 15. a second one-way valve; 16. a single chip microcomputer; 17. a deflation valve; 18. a data acquisition card; 1-1, a sliding plate; 1-2, arc-shaped splints; 1-6, an upper cover plate; 1-7, a CCD camera; 1-8, differential pressure sensor; 1-9, a test base; 1-10, a Wheatstone bridge circuit pipeline; 1-11, a differential pressure sensor interface; 1-12, chuck; 1-13, a first pipe interface; 1-14, valve stent; 301. a first spring; 302. a second spring; 401. the electromagnetic control device comprises a first electromagnetic coil, a first electromagnetic coil 402, a second electromagnetic coil 3-1 and a servo motor; 3-2, a coupler; 3-3, a bearing; 3-4, a ball screw; 3-5, pushing a plate; 3-6, connecting rod; 3-7, a piston rod; 3-8, a cavity; 6-1, Wheatstone bridge circuit.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "axial," "radial," "vertical," "horizontal," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Fig. 1, 2 and 3 show a preferred embodiment of the valve stent performance testing device of the present invention, which includes a multifunctional testing platform 13, a liquid storage tank 4, a power device 12, a single chip computer 16 and a computer 1; the valve stent performance testing device integrates multiple functions, and can test the performance of a plurality of valve stents, including comprehensively measuring the trans-valvular pressure difference of the artificial heart valve stent, the opening area of a heart valve, the strain and vibration frequency of the heart valve stent and the durability of the heart valve.

As shown in FIG. 4, the multifunctional test bench 13 comprises a first test bench I, wherein the first test bench I comprises an upper cover plate 1-6, a differential pressure sensor 1-8, an image acquisition mechanism, a test base 1-9 and a Wheatstone bridge circuit 6-1; the upper cover plate 1-6 is provided with a first through hole, the test base 1-9 is provided with a second through hole, and the first through hole and the second through hole are corresponding in position and can be communicated; the second through hole can be used for placing valve stents 1-14; the differential pressure sensor 1-8 is used for detecting the pressure difference of the valve support 1-14, and the differential pressure sensor 1-8 is connected with the data acquisition card 18; the image acquisition mechanism is used for acquiring images of the working process of the valve stents 1-14; the Wheatstone bridge circuit 6-1 is used for detecting the strain and the vibration frequency of the valve support 1-14 and is connected with the data acquisition card 18; the liquid storage tank 4 is connected with second through holes of the test bases 1-9 through first pipelines through first pipeline interfaces 1-13, and the first through holes of the upper cover plates 1-6 are connected with the liquid storage tank 4 through second pipelines to form a loop; the output end of the power device 12 is connected with a first pipeline, liquid in the liquid storage tank 4 is conveyed to the first test bench I, and the power device 12 is connected with the single chip microcomputer 16; the computer 1 is respectively connected with the differential pressure sensors 1-8, the image acquisition mechanism, the data acquisition card 18, the liquid storage tank 4 and the singlechip 16.

The first test bench is used for testing the cross-valve pressure difference, the opening area of the heart valve and the strain and vibration frequency of the heart valve support.

Preferably, the device also comprises chucks 1-12 and a support plate rail; the chuck 1-12 has a semicircle at one end

The upper cover plate 1-6 is connected with a semicircle at one end of the chuck 1-12, the other end of the chuck 1-12 is connected with the support plate rail in a sliding way, and the chuck 1-12 can slide up and down along the support plate rail. The backup pad track is fixed in the backup pad through L shape riveting, and the backup pad track is stainless steel, and height H is 150mm, wide 41 mm. The chuck 1-12 is made of aluminum alloy and has the size of 75 multiplied by 28 multiplied by 3 mm.

Preferably, the upper cover plate 1-6 is made of transparent organic glass with good light transmittance, so that an image acquisition mechanism can shoot images conveniently, and the image acquisition mechanism is preferably a CCD camera 1-7. The CCD camera 1-7 used for collecting image information is fixed right above the upper cover plate 1-6. The fixing mode can be a support rod or a special camera support. Of the CCD camera 1-7The output end is connected with the computer 1. The CCD camera 1-7 captures the working process of the artificial valve support 1-14, an image with the largest opening angle of the valve is used as the maximum opening area of the valve in a cardiac cycle, then the image is analyzed by utilizing the existing image processing software, the total pixel point number N of the region is calculated, and the area of each pixel point is set as S₁Then the valve opening area S is equal to N S₁K, wherein K is a scaling factor. The value of K is determined by the image processing software employed.

Preferably, the testing base 1-9 is made of transparent organic glass, a second through hole which is vertically communicated with the blood vessel simulation pipeline is arranged in the center of the testing base 1-9, and a step platform is arranged in the second through hole and used for placing the valve support 1-14; the step depth H is 23 +/-3 mm,

has a diameter of

80 to 90 percent of the total weight of the composition. The shoulder of the step platform is communicated with the outside

The Wheatstone bridge circuit pipeline 1-10 and the conductive copper sheet are used for being externally connected with the Wheatstone bridge circuit 6-1, and the condition of the strain and vibration frequency test function in the first test board I is monitored in real time by adopting the built-in Wheatstone bridge circuit 6-1.

As shown in fig. 5, according to the present embodiment, it is preferable that the multifunctional test stand 13 further includes a second test stand II; the second test stand is used for a durability test of the heart valve stents 1-14.

The second test bench II comprises a sliding plate 1-1, a guide rail 501, an arc-shaped clamping plate 1-2, a spring and an electromagnetic coil; a second groove is formed in the center of the guide rail 501, sliding plates 1-1 which are symmetrically arranged are arranged on two sides of the second groove respectively, the sliding plates 1-1 are connected with the guide rail 501 in a sliding mode, arc-shaped clamping plates 1-2 are arranged on the inner sides of the sliding plates 1-1 respectively, and the arc-shaped clamping plates 1-2 are symmetrically arranged on two sides of the second groove to form a circular ring shape and used for placing valve supports 1-14; two sides of the arc-shaped clamping plate 1-2 are respectively provided with a spring, two ends of the spring are respectively connected with the sliding plate 1-1, an electromagnetic coil is arranged near the spring, and the electromagnetic coil is connected with the single chip microcomputer 16. For the durability test of the valve stent 1-14, the single chip microcomputer 16 controls the electromagnetic coil to be powered on and off, the reverse supporting force of the spring is matched to simulate the heart rate, for example, 70 times/minute, and a radial periodic force is applied to the valve stent 1-14, so that the durability of the valve stent 1-14 is tested.

Preferably, the size of the second groove is

The depth H is 5 +/-3 mm; the guide rail 501 is made of aluminum alloy, the size is 150 +/-2 multiplied by 42mm, and the height of the arc-shaped clamping plate 1-2 exceeds that of the valve stent

The length of the arc-shaped clamping plate is 2rad, and the arc-shaped clamping plate is made of aluminum alloy, and soft silica gel with the thickness of 2mm is coated on one side close to the bracket. The clamping plate 1-2 is riveted in the inner side of the sliding plate 1-1.

Preferably, the sliding plate 1-1 and the arc-shaped clamping plate 1-2 are welded and fixed; the springs include a first spring 301 and a second spring 302; the electromagnetic coils include a first electromagnetic coil 401 and a second electromagnetic coil 402. The stainless steel sliding plate 1-1 which is symmetrically arranged on the guide rail 501 and has the specification of 58mm by 58mm provides supporting force through the first spring 301 and the second spring 302, and two ends of each spring are respectively welded on the inner side surface of the sliding plate 1-1. The first electromagnetic coil 401 and the second electromagnetic coil 402 provide attraction force opposite to the spring, respectively; so as to apply periodic load to the tested valve support 1-14 through the matching of the supporting force and the attraction force; the load frequency is controlled by the single chip microcomputer 16, and is preferably 1-10 HZ.

According to the embodiment, preferably, a hydraulic switch 5, a first one-way valve 6, a buffer tank 7, a pressure sensor 9 and a flow sensor 10 are sequentially arranged on the first pipeline from the liquid storage tank 4 to the second through hole of the test base 1-9, and the pressure sensor 9 and the flow sensor 10 are respectively connected with the data acquisition card 18; the output end of the power device 12 is connected with the first pipeline and is positioned between the first one-way valve 6 and the buffer tank 7; and a second one-way valve 15 and a release valve 17 are sequentially arranged on the second pipeline from the first through hole of the upper cover plate 1-6 to the liquid storage tank 4.

The surge tank 7 can eliminate undesirable factors generated by the power plant 12.

According to the embodiment, preferably, the first pipeline is further provided with a particle injector 11; the particle injector 11 is located behind the flow sensor 10.

According to the present embodiment, preferably, the first pipe is further provided with an overflow valve 8; the overflow valve 8 is located between the buffer tank 7 and the pressure sensor 9.

According to the present embodiment, it is preferable that the second pipeline is further provided with a pressure regulator 14; the pressure regulator 14 is located between the first through hole of the upper cover plate 1-6 and the second check valve 15.

As shown in fig. 6, according to the present embodiment, preferably, the power device 12 includes a servo motor 3-1, a coupler 3-2, a bearing 3-3, a ball screw 3-4, two push plates 3-5, a piston rod 3-7 and a cavity 3-8;

the output end of the servo motor 3-1 is connected with one end of a ball screw 3-4 through a coupler 3-2; the other end of the ball screw 3-4 is connected with the first push plate 3-5, and the two ends of the ball screw 3-4 are respectively arranged in the bearings 3-3; the first push plate 3-5 and the second push plate 3-5 are connected through a connecting rod 3-6, one end of the piston rod 3-7 is connected with the second push plate 3-5, and the other end of the piston rod extends into the cavity 3-8; the cavity 3-8 is communicated with the first pipeline through a three-way pipe 3-9, and the piston rod 3-7 makes reciprocating linear motion, so that the system generates a pulsating flow environment with characteristics similar to those of a human body.

According to the embodiment, preferably, the liquid storage tank 4 is provided with a temperature probe 2 and a heater 3;

the temperature probe 2 is connected with a data acquisition card 18, and the data acquisition card 18 is connected with the computer 1; the heater 3 is connected with the singlechip 16.

According to the embodiment, preferably, a first groove is arranged in the second through hole of the test base 1-9; the first groove is used for placing the valve stents 1-14.

According to the embodiment, preferably, a differential pressure sensor interface 1-11 is further arranged on the test base 1-9, and the differential pressure sensor interface 1-11 is located below the second through hole; the upper cover plate 1-6 is also provided with a third pipeline 2-11, and the third pipeline 2-11 is positioned above the first through hole; the input end of the differential pressure sensor 1-8 is connected with the differential pressure sensor interface 1-11, and the output end is connected with the third pipeline 2-11. The valve support 1-14 is placed in the second through hole, the differential pressure sensor 1-8 is used for detecting the trans-valve differential pressure of the valve support 1-14 and transmitting the data to the data acquisition card 18, and the data acquisition card 18 transmits the data to the computer 1.

According to the invention, the digitized blood simulation liquid in the liquid storage tank 4 is conveyed into the first pipeline by the power device 12 according to the characteristic of human blood pulsating flow, and then flows back into the liquid storage tank 4 through the first test bench and the second pipeline to form a circulating system, and as shown in fig. 2, a blood circulating structure similar to a human body is formed; the first pipeline and the second pipeline are blood vessel simulation pipelines; the blood simulation solution, i.e. the mixed solution of physiological saline and glycerol, has viscosity of 3.5CP and density of 1.06g/m³. Simultaneously, the heater 3 and the pressure regulator 14 are utilized to enable the whole system to be close to the human blood flow environment. The dynamic information generated by the pressure sensor 9, the flow sensor 10, the wheatstone bridge, etc. is collected by the data acquisition card 18 and presented in a visual manner by the computer 1 processing.

As shown in fig. 7, which is a schematic diagram of a wheatstone bridge circuit, the specific values of R1, R2, and R3 can be determined by an experimenter. But the balance relation needs to be satisfied: R2R 4R 1R 3. And R3 is the resistance of the valve stent 1-14 to be tested. The valve stent 1-14 may be any one of the types of mechanical valve, bioengineered valve, etc., such as a prosthetic mechanical valve in fig. 7a and a bioengineered valve in fig. 7 b. The circuit is in equilibrium before testing, and strain, fatigue failure, etc. can occur after the valve stents 1-14 have been used for a period of time. The balance of the circuit is thus broken and the data acquisition card 18 collects the data of the Wheatstone bridge circuit 6-1 and transmits it to the computer 1.

The weakest artificial heart valve stentIs where the valve is attached to the stent, and thus the attachment of the valve to the stent is the primary place for durability measurement based on the "barrel effect". In the durability test of the stent in the second test bench II, a resistance strain gauge needs to be pasted on the valve stent 1-14 to be tested, the resistance strain gauge is made by making a resistance wire into a grid shape and pasting the resistance wire between two layers of thin paper or plastic films, when the object deforms, the strain gauge deforms, and the resistance of the strain gauge is balanced by the resistance R of the bridge_xIs changed into R_xThe current changes accordingly, the information is transmitted to the computer 1 for processing by the data acquisition card 18, and then the deformation quantity of the object is calculated according to the relation between the delta R and the solid deformation. Therefore, the strain of the artificial valve support 1-14 in the working process after being implanted into the human body can be completed only by connecting the resistance strain gauge with the data acquisition card 18 and the computer 1; . The resistance strain gauge should be attached to the valve and junction stent of the stent to be tested in advance in preparation. In the strain and vibration frequency test in the first test bench I, the valve support 1-14 is directly regarded as a resistor, a resistor strain gauge is not needed, and a conductive copper sheet is placed at a stepped platform shoulder arranged in the second through hole and connected into the Wheatstone bridge circuit 6-1.

The power device 12 controls the piston rod 3-7 and the cavity 3-8 to convey the blood simulation liquid in the liquid storage tank 4 to a test system through the three-way pipe 3-9, and the piston rod 3-7 and the cavity 3-8 are matched to generate pulsating flow similar to a human blood vessel; the pressure and the flow in the first pipeline are respectively measured by the pressure sensor 9 and the flow sensor 10 in combination with the particle injector 11, and are collected and uploaded to the computer 1 by the data acquisition card 18. The operation of the first testing station I is described in detail with reference to fig. 3 and 4 as follows:

the first step is as follows: an inspection system: and checking whether the sealing performance of each interface is good or not, and then checking whether each component can work normally or not. Such as: pressure sensor 9, flow sensor 10, power plant 12, etc.; pressing down an upper cover plate 1-6 in a first test bench I until the upper cover plate is sealed with a test base 1-9; the singlechip 16 and the servo motor 3-1 of the power device 12 are started, and the computer 1 sets the program of the singlechip 16 to control the ball screw 3-4 connected with the servo motor 3-1 to generate pulsating flow; the heart rate is preferably 70 times/min, and the cardiac output is adjustable: 4 plus or minus 0.05, 5 plus or minus 0.05 or 6 plus or minus 0.05 liter/minute;

the second step is that: opening the air release valve 1710s to completely exhaust the air in the pipeline, and opening the particle injector 11 to inject the polystyrene particles of 20um into the pipeline; setting a heater 3 to heat the blood simulation liquid in the liquid storage tank 4 to 37 +/-1 ℃;

the third step: the pressure of the system is regulated to 16-100 KPa through the pressure regulator 14, and whether the whole system meets the standard or not is observed through data collected by the data collection card 18, for example, the value of the pressure sensor 9 should be 16-100 KPa, the value of the flow sensor should be 4 +/-0.05, 5 +/-0.05 or 6 +/-0.05 liter/minute, and the heart rate is 60-80 times/minute, or is set by the user according to the experimental purpose. If the acquired data is not in accordance with the requirements of the experiment, the computer 1 can adjust the program of the singlechip 16 and change the rotating speed of the servo motor 3-1 so as to enable the whole system to generate a pulsating flow meeting the standard; or adjusted to the parameter environment specified by the tester.

The fourth step: the invention is used as a precision medical instrument testing device, has higher requirements on stability and reliability, and the stable and reliable pressure value and flow value are the precondition for obtaining the accuracy testing result. Therefore, the system was run for three minutes to see if an unstable phenomenon occurred. Such as: system pressure and pipeline flow are suddenly high and suddenly low, liquid leaks, flow and pressure are unstable, impact load and the like; if the situation occurs, the power supply is immediately turned off, the device is overhauled, and then the preparation work in the first step is returned to perform the test operation of the device again.

The fifth step: the upper cover plate 1-6 is opened, and the artificial valve support 1-14 is placed on the testing base 1-9, wherein the valve support 1-14 can be any one, such as an artificial mechanical valve shown in figure 7a and a biological engineering valve shown in figure 7 b. And covering the sealing cover plates 1-6. Setting the exposure time of the CCD cameras 1-7 to be 2us, setting the pixels to be 1280 x 800, preparing for subsequent calculation of the valve opening area, and taking down the valve stent after running for a specific time, wherein the specific running time can be determined by a tester according to the purpose of an experiment;

and a sixth step: collecting information, analyzing data:

1. the working process of the artificial valve support 1-14 is captured by the CCD camera 1-7, and one image with the maximum valve opening angle is used as the maximum opening area of the valve in one cardiac cycle. Then, analyzing the image by using the existing image processing software, calculating the total pixel point number N of the region, and setting the area of each pixel point as S₁. The valve opening area S-N S₁K, wherein K is a scaling factor.

2. The data of the differential pressure sensor 1-8 and the Wheatstone bridge circuit 6-1 are collected in real time by the data acquisition card 18 and uploaded to the computer 1 to be displayed in a graphic mode. The wheatstone bridge circuit 6-1 is well known for testing the strain and vibration frequency of metal objects. The abscissa of the graph is time t, and the ordinate is the cross-flap pressure difference. The pressure differential at any time during operation of the valve stent can thus be viewed. The ordinate can also be a scale value and is used for recording the strain condition of the valve stent at any time in the working process. Finally, the performance of the tested valve stent is analyzed by a tester through a control variable method. The ordinate may also be the vibration frequency.

The operation of the second testing station II is described in detail with reference to fig. 3 and 5 as follows:

the first step is as follows: checking whether each part of the system is normal, such as the computer 1, the singlechip 16 and the electromagnetic coil. If the work can not be normally carried out, the parts are immediately replaced; the computer 1 is provided with a singlechip 16 program, so that the electromagnetic coil is periodically electrified to adsorb the metal sliding plate 1-1 and generate a suction force opposite to the spring. Thereby making the arc splint 1-2 do periodic reciprocating linear motion. A radial periodic load is applied to the valve supports 1-14 by simulating the heart rate at a frequency of 60-70 times/minute, and the force is controlled by the single chip microcomputer 16. The load frequency and the load size can also be adjusted by a tester according to the experimental purpose. If the device is normal, carrying out the next step, otherwise, carrying out related debugging; the normal state of the device mainly means whether the load frequency is within an allowable range. The related debugging refers to checking the cause of a failure, replacing a failed component, and checking a program.

And secondly, placing the valve support 1-14 to be tested into the center of the arc-shaped clamping plate 1-2, and pre-loading the valve support 1-14 by setting a program through the singlechip 16. Repeating the related operation of the first step until the valve support 1-14 is damaged, or loading for a certain time and then putting the valve support into the first test bench I to observe whether the opening area, the trans-valve pressure difference and the like are changed;

the third step: collecting information, analyzing data: the data acquisition card 18 is used for acquiring the data of the Wheatstone bridge circuit 6-1 in real time and uploading the data to the computer 1 for displaying in a graphic mode. The Wheatstone bridge circuit 6-1 is used for testing the fatigue deformation of the support, wherein the fatigue deformation test needs to use a resistance strain gauge, and the strain and vibration frequency test does not need, but the test principle is the same. Therefore, before the first preparation step, the test should first apply the corresponding strain resistance R to the valve-stent junction of the stent to be tested₃The data collection and processing are the same as in the previous method, and are not described in detail here.

The invention strengthens the sealing performance, and sealing rings are used on the first test bench I, the Wheatstone bridge circuit pipelines 1-10, the test bases 1-9, the upper cover plate 1-6 and the like, so that the measurement error generated by external bad factors can be greatly reduced.

The valve support testing device comprises a multifunctional testing table 13, which can dynamically test the multifunctional performance of the valve supports 1-14, wherein a first testing table I can realize the strain and vibration frequency test, the cross-valve pressure difference test and the opening area test of the valve supports 1-14, and a second testing table II can realize the durability test of the valve supports; the first test bench I and the second test bench II can simultaneously test, so that the dynamic test of a plurality of performances of the artificial valve supports 1-14 can be simultaneously realized, and the artificial valve supports can also be independently tested, and are convenient and flexible to use; the multifunctional performance test device overcomes the defect that the conventional test method is usually that one detection device can only test single performance, has wide application range and universal adaptability, and is suitable for multifunctional performance tests of mechanical valves, biological valves, mitral valves, tricuspid valves, aortic valves and the like. The invention has the advantages of ingenious structural design, novel and reasonable conception, capability of generating a pulsating flow environment with pressure, flow and heart rate similar to human blood flow, small volume and convenient movement of users, thereby greatly improving the working efficiency.

It should be understood that although the present description has been described in terms of various embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and those skilled in the art will recognize that the embodiments described herein may be combined as suitable to form other embodiments, as will be appreciated by those skilled in the art.

The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.

Claims

1. A valve support performance testing device is characterized by comprising a multifunctional test bench (13), a liquid storage tank (4), a power device (12), a single chip microcomputer (16) and a computer (1);

the multifunctional test bench (13) comprises a first test bench I, wherein the first test bench I comprises an upper cover plate (1-6), a differential pressure sensor (1-8), an image acquisition mechanism, a test base (1-9) and a Wheatstone bridge circuit (6-1); the upper cover plate (1-6) is provided with a first through hole, the test base (1-9) is provided with a second through hole, and the first through hole corresponds to the second through hole in position and can be communicated with the second through hole; the second through hole can be used for placing a valve stent (1-14); the differential pressure sensor (1-8) is used for detecting the differential pressure of the valve support (1-14), and the differential pressure sensor (1-8) is connected with the data acquisition card (18); the image acquisition mechanism is used for acquiring images of the valve stents (1-14); the Wheatstone bridge circuit (6-1) is arranged on the test base (1-9) and is connected with the data acquisition card (18);

the multifunctional test bench further comprises a second test bench II; the second test bench II comprises a sliding plate (1-1), a guide rail (501), an arc-shaped clamping plate (1-2), a spring and an electromagnetic coil; a second groove is formed in the guide rail (501), sliding plates (1-1) which are symmetrically arranged are arranged on two sides of the second groove respectively, the sliding plates (1-1) are connected with the guide rail (501) in a sliding mode, arc-shaped clamping plates (1-2) are arranged on the inner sides of the sliding plates (1-1) respectively, and the arc-shaped clamping plates (1-2) are symmetrically arranged on two sides of the second groove to form a circular ring shape; springs are respectively arranged on two sides of the arc-shaped clamping plate (1-2), two ends of each spring are respectively connected with the sliding plate (1-1), an electromagnetic coil is arranged near each spring and connected with the single chip microcomputer (16);

the liquid storage tank (4) is connected with the second through hole of the testing base (1-9) through a first pipeline, and the first through hole of the upper cover plate (1-6) is connected with the liquid storage tank (4) through a second pipeline to form a loop;

the output end of the power device (12) is connected with a first pipeline, liquid in the liquid storage tank (4) is conveyed to the first test bench I, and the power device (12) is connected with the single chip microcomputer (16);

the computer (1) is respectively connected with the differential pressure sensors (1-8), the image acquisition mechanism, the data acquisition card (18), the liquid storage tank (4) and the singlechip (16).

2. The valve stent performance testing device according to claim 1, wherein a hydraulic switch (5), a first one-way valve (6), a buffer tank (7), a pressure sensor (9) and a flow sensor (10) are sequentially arranged on the first pipeline from the liquid storage tank (4) to the second through hole of the testing base (1-9), and the pressure sensor (9) and the flow sensor (10) are respectively connected with a data acquisition card (18); the output end of the power device (12) is connected with the first pipeline and is positioned between the first one-way valve (6) and the buffer tank (7);

and a second one-way valve (15) and a release valve (17) are sequentially arranged on the second pipeline from the first through hole of the upper cover plate (1-6) to the liquid storage tank (4).

3. The valve-stent performance testing device of claim 2, wherein the first pipeline is further provided with a particle injector (11); the particle injector (11) is located after the flow sensor (10).

4. The valve support performance testing device of claim 2, wherein the first pipeline is further provided with an overflow valve (8); the overflow valve (8) is positioned between the buffer tank (7) and the pressure sensor (9).

5. The valve-stent performance testing device of claim 2, wherein the second conduit is further provided with a pressure regulator (14); the pressure regulator (14) is positioned between the first through hole of the upper cover plate (1-6) and the second one-way valve (15).

6. The valve support performance testing device according to claim 1, wherein the power device (12) comprises a servo motor (3-1), a coupler (3-2), a bearing (3-3), a ball screw (3-4), two push plates, a piston rod (3-7) and a cavity (3-8);

the output end of the servo motor (3-1) is connected with one end of a ball screw (3-4) through a coupler (3-2); the other end of the ball screw (3-4) is connected with the first push plate, and the two ends of the ball screw (3-4) are respectively arranged in the bearings (3-3); the first push plate and the second push plate are connected through a connecting rod (3-6), one end of the piston rod (3-7) is connected with the second push plate, and the other end of the piston rod extends into the cavity (3-8); the cavities (3-8) are communicated with the first pipeline.

7. The valve stent performance testing device according to claim 1, wherein a temperature probe (2) and a heater (3) are arranged on the liquid storage tank (4);

the temperature probe (2) is connected with a data acquisition card (18), and the data acquisition card (18) is connected with the computer (1); the heater (3) is connected with the singlechip (16).

8. The valve-stent performance testing device according to claim 1, wherein a first groove is arranged in the second through hole of the testing base (1-9); the first groove is used for placing a valve stent (1-14).

9. The valve support performance testing device according to claim 1, wherein the testing base (1-9) is further provided with a differential pressure sensor interface (1-11), and the differential pressure sensor interface (1-11) is located below the second through hole; the upper cover plate (1-6) is also provided with a third pipeline (2-11), and the third pipeline (2-11) is positioned above the first through hole; the input end of the differential pressure sensor (1-8) is connected with the differential pressure sensor interface (1-11), and the output end of the differential pressure sensor is connected with the third pipeline (2-11).