Sustainable cleaning system of miniature axial flow blood pump

Abstract

The sustainable cleaning system comprises a liquid bottle, the liquid bottle is connected with a filling device through a liquid inlet pipe, the filling device is communicated with the micro axial flow blood pump through a liquid outlet pipe and a conveying pipe, a pressure sensor is installed on the liquid outlet pipe, and a control device is connected with the filling device, the pressure sensor and the micro axial flow blood pump. The filling device comprises a filling box, a driving cylinder is installed in the filling box, a piston of the driving cylinder is connected with a motor through a transmission assembly, and cleaning liquid sent out by the liquid bottle is pressurized by the driving cylinder and then continuously and evenly sent into the miniature axial flow blood pump. When the pressure sensor detects that the pressure value of the cleaning fluid is too large, sound-light alarm is performed. When it is detected that the difference value between the cleaning fluid pressure value and the preset pressure value exceeds the set value, the rotating speed of the motor is controlled to adjust the cleaning fluid pressure to be equal to the preset pressure value. When the micro axial flow blood pump is cleaned, continuous, uniform and constant-pressure cleaning liquid can be provided, it is guaranteed that blood cannot enter the blood pump, the service life of the blood pump is prolonged, and the working efficiency of the blood pump is improved.

Description

Technical Field

[0001] The invention relates to a sustainable cleaning system for a micro axial flow blood pump, belonging to the technical field of blood pump cleaning equipment. Background Art

[0002] Cardiorenal syndrome refers to a clinical syndrome in which acute or chronic dysfunction of the heart or kidney induces acute or chronic dysfunction of another organ. More than 60% of patients hospitalized for acute decompensated heart failure exhibit moderate to severe chronic kidney disease at the time of admission. The pathophysiological mechanism of abnormal renal function in heart failure is quite complex, and one of the most important factors is insufficient renal vascular perfusion. It can be seen that effectively improving the treatment level of patients with cardiorenal syndrome has become a major clinical need. At present, micro-axial flow blood pumps have become the greatest possibility to improve renal perfusion and assist blood circulation in patients with heart failure. Studies have shown that micro-axial flow blood pumps can help increase urine output and improve renal function in patients with cardiorenal syndrome. The micro-axial flow blood pump is a percutaneously delivered, catheter-mounted axial flow pump that can be quickly implanted through minimally invasive surgery under the guidance and monitoring of imaging equipment to provide continuous blood flow from the left ventricle through the aortic valve to the ascending aorta.

[0003] It can be found from actual use that the micro axial flow blood pump converts mechanical energy into kinetic energy for transporting blood through the high-speed rotation of the impeller shaft on the bearing. However, there is a gap between the impeller shaft and the bearing, and blood may enter this gap to form a thrombus or damage the motor, thereby affecting the normal operation of the blood pump. In order to prevent blood from entering the blood pump, or more precisely, to prevent blood from entering the gap between the shaft and the bearing inside the blood pump, most of the existing technologies at home and abroad use a cleaning device to inject cleaning fluid into the pump to prevent blood from entering and inhibit thrombus formation, while also lubricating the high-speed rotating bearings in the pump.

[0004] The existing cleaning device mainly includes a plunger pump, which controls the piston of the plunger pump to make reciprocating linear motion through a motor, and is equipped with a one-way valve to achieve the suction and perfusion of the cleaning liquid. 5% glucose or sodium bicarbonate solution is perfused into the blood pump in vitro to clean the pump. For example, the Chinese invention patent application with publication number CN115807766A discloses a plunger pump zero position calibration method, a blood pump perfusion cleaning device and a blood pump system, which achieves good cleaning of the blood pump, but the one-way plunger pump used cannot achieve continuous perfusion of the cleaning liquid. The reason is that the cleaning pipeline of the plunger pump will be depressurized during the process of pumping the cleaning liquid. In order to prevent blood from entering the blood pump, it is necessary to add an additional balloon structure with hydraulic energy storage to maintain the hydraulic pressure of the cleaning pipeline. It can be seen that it has the following defects: the balloon structure cannot ensure the stability of the liquid pressure, and the intermittent supply of cleaning liquid obviously has the risk of blood entering the blood pump. In addition, the cleaning fluid flow of the one-way plunger pump is uneven, and the piston speed needs to be accelerated during the cleaning fluid suction process to reduce the cleaning fluid suction time. However, the piston acceleration during suction will easily wear the piston and piston cylinder of the plunger pump. Summary of the invention

[0005] The purpose of the present invention is to provide a sustainable cleaning system for a micro axial flow blood pump, which can provide continuous, uniform, and constant-pressure cleaning fluid when cleaning the micro axial flow blood pump, thereby ensuring that blood does not enter the micro axial flow blood pump and improving the life and working efficiency of the blood pump.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A sustainable cleaning system for a micro-axial blood pump comprises a liquid bottle, a perfusion device and a pressure sensor, wherein the liquid bottle is connected to the perfusion device via a liquid inlet pipe, the perfusion device is connected to one end of a delivery pipe via a liquid outlet pipe, the pressure sensor is installed on the liquid outlet pipe, the other end of the delivery pipe is used to communicate with the micro-axial blood pump, a control device is connected to the perfusion device, the pressure sensor and the micro-axial blood pump, wherein: the perfusion device comprises a perfusion box, a drive cylinder is installed in the perfusion box, the piston of the drive cylinder is connected to a motor via a transmission assembly, the piston is driven by the motor to move by the transmission assembly The drive cylinder is extended in and out for reciprocating linear motion, so that the cleaning fluid delivered from the liquid bottle is continuously and evenly delivered to the micro-axial blood pump after being pressurized by the drive cylinder; when the pressure sensor detects that the cleaning fluid pressure value is too large and reaches the alarm pressure threshold, an audible and visual alarm is triggered, otherwise the cleaning fluid pressure is continued to be detected, wherein, when the cleaning fluid pressure value detected by the pressure sensor is not equal to the preset pressure value and the difference between the two exceeds the set value, the control device adjusts the cleaning fluid pressure by controlling the motor speed to make the cleaning fluid pressure value equal to the preset pressure value, and the motor enters the holding mode, otherwise the motor maintains the original speed.

[0008] The advantages of the present invention are:

[0009] The present invention can provide continuous, uniform, and constant-pressure cleaning fluid when cleaning the micro-axial blood pump, thereby solving the problem of discontinuous and uneven perfusion of the cleaning fluid, and the piston is not prone to wear during operation. The continuous and uniform provision of the cleaning fluid ensures that blood does not enter the micro-axial blood pump, thereby ensuring the long-term stable and normal operation of the micro-axial blood pump. The cleaning fluid achieves the purpose of cleaning, cooling, and avoiding wear of the micro-axial blood pump, thereby improving the service life and working efficiency of the micro-axial blood pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the composition of the sustainable cleaning system of the micro axial flow blood pump of the present invention.

[0011] Figure 2 It is a schematic diagram of the external structure of the perfusion device.

[0012] Figure 3 It is a schematic diagram of the internal structure of the perfusion device.

[0013] Figure 4 yes Figure 3 The schematic diagram of the transverse cross-section of the piston cylinder of the perfusion device is shown (the motor, the liquid inlet pipe and the liquid outlet pipe are not shown).

[0014] Figure 5 is a schematic diagram of the longitudinal section of the perfusion device (in Figure 4 AA cutting is performed in the

[0015] Figure 6 It is a schematic diagram of the structure of the bottom shell of the perfusion box.

[0016] Fig. 7A It is a schematic diagram of the filling instructions when the piston of the filling device is extended to the full position.

[0017] Figure 7B It is a schematic diagram of the filling instructions when the piston of the filling device is extended into place.

[0018] Figure 8 It is a block diagram of the components of the control device.

[0019] Fig. 9 It is a flow chart of the implementation principle of the sustainable cleaning system of the micro axial flow blood pump of the present invention. DETAILED DESCRIPTION

[0020] like Figures 1 to 9As shown, the sustainable cleaning system of the micro-axial blood pump of the present invention includes a liquid bottle 701, an infusion device, a liquid filter 801, a pressure sensor 802 and a control device 10. The liquid bottle 701 is connected to the liquid inlet interface 608 of the infusion device via the liquid inlet tube 7, and the liquid outlet interface 609 of the infusion device is connected to one end of the delivery tube 901 via the liquid outlet tube 8. The liquid filter 801 and the pressure sensor 802 are installed on the liquid outlet tube 8. The liquid filter 801 is between the pressure sensor 802 and the infusion device. The other end of the delivery tube 901 is used to connect the micro-axial blood pump 9. The control device 10 is electrically connected to the infusion device, the pressure sensor 802 and the micro-axial blood pump 9, wherein: the infusion device includes an infusion box 1, a driving cylinder is installed in the infusion box 1, the piston 5 of the driving cylinder is connected to the motor 4 via the transmission assembly 3, the motor 4 is electrically connected to the control device 10, and the piston 5 is driven by the transmission assembly 3 relative to the driving cylinder under the drive of the motor 4. The cylinder makes a reciprocating linear motion of extending and extending so that the cleaning liquid sent out by the liquid bottle 701 is pressurized through the driving cylinder and then continuously and evenly delivered to the micro-axial blood pump 9; when the pressure sensor 802 detects that the cleaning liquid pressure value is too large and reaches the alarm pressure threshold, there may be a situation where the cleaning liquid is blocked when being delivered to the micro-axial blood pump 9, so an audible and visual alarm is performed, otherwise the pressure sensor 802 continues to detect the cleaning liquid pressure, wherein, when the cleaning liquid pressure value detected by the pressure sensor 802 is not equal to the preset pressure value and the difference between the cleaning liquid pressure value and the preset pressure value exceeds the set value, the control device 10 adjusts the cleaning liquid pressure by controlling the speed of the motor 4 so that the measured cleaning liquid pressure value is equal to the preset pressure value, so that the motor 4 enters the holding mode and maintains the current speed, otherwise, that is, if the two are equal or the difference between the two is less than or equal to the set value, the speed of the motor 4 is not adjusted, and the motor 4 maintains the original speed.

[0021] In actual implementation, it is preferred to use a PID algorithm to adjust the cleaning liquid pressure value. Specifically, when the cleaning liquid pressure value in the liquid outlet pipe 8 is close to the preset pressure value, the speed of the motor 4 is slowly and uniformly adjusted (the speed of the motor 4 is slowly and uniformly increased / decreased) until the measured cleaning liquid pressure value is equal to the preset pressure value. Of course, when the motor 4 is started to run, if the measured cleaning liquid pressure value is significantly different from the preset pressure value, the speed of the motor 4 can be appropriately and quickly adjusted.

[0022] like Figures 3 to 6The driving cylinder includes a piston cylinder 6 and a piston 5. The interior of the piston cylinder 6 is divided into a liquid inlet groove 605, a piston groove 606 and a liquid outlet groove 607 by two parallel partitions 61. The piston groove 606 is located between the liquid inlet groove 605 and the liquid outlet groove 607. A liquid inlet interface 608 is provided on the side of the piston cylinder 6 corresponding to the liquid inlet groove 605, and a liquid outlet interface 609 is provided on the side of the piston cylinder 6 corresponding to the liquid outlet groove 607. Usually, the liquid inlet interface 608 and the liquid outlet interface 609 are diagonally arranged on the piston cylinder 6, the liquid inlet interface 608 is in the perfusion box 1, and the liquid outlet interface 609 extends out of the perfusion box 1. Two one-way valves are separately installed on each partition 61. The one-way valve only allows liquid to flow in one direction. Each one-way valve on a partition 61 is opposite to a corresponding one-way valve on the other partition 61 and forms a pair. Usually, the one-way valve is installed at the end position of the partition 61, and the inlet and outlet directions of each one-way valve are consistent, such as Figure 4 A first one-way valve 601 and a second one-way valve 602 are installed on one partition 61, and a third one-way valve 603 and a fourth one-way valve 604 are installed on another partition 61. The first one-way valve 601 and the third one-way valve 603 are opposite to each other and form a pair, and the second one-way valve 602 and the fourth one-way valve 604 are opposite to each other and form another pair. The inlet of the first one-way valve 601 and the second one-way valve 602 and the outlet of the third one-way valve 603 and the fourth one-way valve 604 are connected to the piston groove 606, the outlet of the first one-way valve 601 and the second one-way valve 602 are connected to the liquid outlet groove 607, and the inlet of the third one-way valve 603 and the fourth one-way valve 604 is connected to the liquid inlet groove 605. The piston rod 503 of the piston 5 is arranged through the piston cylinder 6, and the piston head 502 at one end of the piston rod 503 is movably clamped between two partitions 61 and is located in the piston groove 606. The other end of the piston rod 503 extending out of the piston cylinder 6 is provided with a driving end 501, and the driving end 501 is connected to the motor 4 via the transmission assembly 3. The piston 5 is driven by the motor 4 through the transmission assembly 3 to make a reciprocating linear movement in the piston groove 606. Specifically, the piston head 502 is reciprocating linear movement between the two pairs of one-way valves.

[0023] In the present invention, the first one-way valve 601, the second one-way valve 602, the third one-way valve 603 and the fourth one-way valve 604 have the same structure and perform the same function, and all of them only allow the liquid to flow in one direction. The liquid inlet groove 605 is connected to the liquid inlet interface 608, allowing external liquid to enter the liquid inlet groove 605 through the liquid inlet interface 608. Similarly, the liquid outlet groove 607 is connected to the liquid outlet interface 609, allowing the pressurized liquid to flow out from the liquid outlet groove 607 through the liquid outlet interface 609. The movement of the piston 5 in the piston groove 606 plays a role in pressurizing the liquid. In actual design, the piston cylinder 6 is in the shape of a rectangle, the piston groove 606 is in the shape of a cylinder that matches the piston head 502, and a sealing ring is installed on the piston head 502. Figure 5The piston head 502 is provided with a first sealing ring 5021 and a second sealing ring 5022. Of course, the number and position of the sealing rings are not limited and can be designed reasonably. Figure 5 In order to improve the sealing performance, a sealing ring 6081 is installed at the through hole of the piston cylinder 6 where the piston rod 503 passes through.

[0024] In the present invention, the perfusion box 1 is formed by the top shell 101 and the bottom shell 102 being buckled together, the transmission assembly 3 includes a transmission shaft 303, the transmission shaft 303 is connected to the output shaft of the motor 4 via the coupling 2, a positioning member 301 and a transmission gear 302 are installed on the transmission shaft 303, the positioning member 301 is rotatably installed on the positioning seat 1022, the positioning seat 1022 is installed on the bottom shell 102 of the perfusion box 1, one side of the driving end 501 of the piston 5 is provided with a rack belt 5010 for engaging with the transmission gear 302, and the other side of the driving end 501 is placed on a guide seat 1021 installed on the bottom shell 102 of the perfusion box 1, and the driving end 501 of the piston 5 is driven by the transmission gear 302 to make a linear movement on the guide seat 1021.

[0025] Specifically, a groove 5011 is recessed on one side of the guide seat 1021 on which the driving end 501 is placed. A limiting column 1020 is convexly provided on the guide seat 1021. The limiting column 1020 extends into the groove 5011 and is limited to move only within the groove 5011. The function of the limiting column 1020 is to enable the piston head 502 to move back and forth in a linear manner within a set range. The limiting column 1020 cooperates with the groove 5011 to better ensure that the piston 5 only performs linear motion and moves within a set range (set distance). The length of the rack belt 5010 is greater than the length of the groove 5011. The length of the groove 5011 limits the moving distance of the piston head 502 in the piston groove 606. Figure 4 The rack belt 5010 includes a plurality of teeth arranged at intervals, and the teeth are used to mesh with the teeth of the transmission gear 302.

[0026] In the present invention, the reciprocating linear motion of the piston 5 is preferably designed to be a uniform motion, so that the wear on the piston surface can be greatly reduced. In actual implementation, by controlling the direction and speed of the motor 4, the direction and speed of the transmission gear 302 can be controlled, thereby controlling the moving direction and speed of the piston 5.

[0027] In actual design, the positioning seat 1022 is three groove plates arranged separately and side by side, that is, two outer groove plates with arc grooves and a middle groove plate between the two outer groove plates, and the arc groove area of ​​the middle groove plate is larger than the arc groove area of ​​the outer groove plate. Accordingly, the positioning member 301 includes a positioning cylinder 3011, and a convex ring 3012 is convexly provided at the middle part of the positioning cylinder 3011. The two ends of the positioning cylinder 3011 that are exposed from the convex ring 3012 are respectively placed on the two outer groove plates, and the convex ring 3012 is placed on the middle groove plate, so that the convex ring 3012 is limited between the two outer groove plates and rotates on the middle groove plate, so that the transmission component 3 does not undergo axial displacement.

[0028] In actual design, the guide seat 1021 can be a plurality of support groove plates separated and arranged side by side, each support groove plate is provided with an arc-shaped groove, and the limiting column 1020 is arranged in the arc-shaped groove. The size of each arc-shaped groove is consistent and is adapted to the shape of the corresponding surface of the driving end head 501, so that the driving end head 501 can move smoothly on the guide seat 1021, and the guide seat 1021 provides a guide for the movement of the driving end head 501.

[0029] Furthermore, in actual design, Figure 5 As shown, a protective cover 1011 may be provided inside the top shell 101 of the perfusion box 1, and the protective cover 1011 is used to protect the transmission shaft 303 and the transmission gear 302 to prevent them from accidentally detaching.

[0030] Figure 3 Combination Fig. 7A and Figure 7B To understand, when the transmission gear 302 rotates (such as counterclockwise), it drives the piston head 502 to extend into the piston groove 606 (such as Figure 7B ), when the transmission gear 302 rotates in the reverse direction (such as clockwise), it drives the piston head 502 to extend out of the piston groove 606 (such as Fig. 7A ).

[0031] Specifically, the piston head 502 reciprocates in the piston groove 606 in a linear manner. Fig. 7A , Figure 7B The two situations in which the piston head 502 is extended into the piston groove 606 and is inserted into the piston groove 606 are shown respectively. Fig. 7A When the piston head 502 moves to the right and extends to the right position, the piston head 502 is in Fig. 7AAs shown in the figure, the pressure of the space on the left side of the piston groove 606 is lower than the pressure inside the liquid inlet groove 605. The cleaning liquid entering the liquid inlet groove 605 from the liquid inlet interface 608 enters the piston groove 606 through the third one-way valve 603, and the cleaning liquid on the right side of the piston head 502 in the piston groove 606 is squeezed by the piston head 502. At this time, the pressure of the space on the right side of the piston groove 606 is greater than the pressure inside the liquid outlet groove 607. Therefore, the cleaning liquid enters the liquid outlet groove 607 from the space on the right side of the piston groove 606 through the second one-way valve 602, thus completing a perfusion cleaning process. Then the piston head 502 moves in the opposite direction, that is, moves to the left, as shown in FIG. Figure 7B When the piston head 502 moves to the left and is inserted into place, the piston head 502 is in Figure 7B The left side of the piston groove 606 is shown. At this time, the pressure of the space on the right side of the piston groove 606 is lower than the internal pressure of the liquid inlet groove 605. The cleaning liquid entering the liquid inlet groove 605 from the liquid inlet interface 608 enters the piston groove 606 through the fourth one-way valve 604, and the cleaning liquid on the left side of the piston head 502 in the piston groove 606 is squeezed by the piston head 502. At this time, the pressure of the space on the left side of the piston groove 606 is greater than the internal pressure of the liquid outlet groove 607. Therefore, the cleaning liquid enters the liquid outlet groove 607 from the space on the left side of the piston groove 606 through the first one-way valve 601, and another perfusion and cleaning process is completed. The above two perfusion and cleaning processes are carried out continuously. It can be seen that based on the above structural design, no matter which direction the piston head 502 moves, the cleaning liquid can enter from the liquid inlet interface 608 and then flow out from the liquid outlet interface 609. Therefore, the present invention can well achieve the purpose of continuously perfusing the cleaning liquid into the micro-axial blood pump 9 for cleaning. Here, Fig. 7A and Figure 7B The arrow in the figure (indicated by reference numeral 66) shows the direction of liquid flow. In addition, the motor 4 drives the piston 5 to move at a constant speed through the transmission assembly 3, so that the present invention can achieve the effect of continuously and evenly perfusing the cleaning liquid to the micro-axial blood pump 9.

[0032] like Figure 1As shown, the liquid bottle 701 of the sustainable cleaning system of the micro-axial blood pump of the present invention is used to provide cleaning liquid to the perfusion box 1 of the perfusion device via the liquid inlet pipe 7. The cleaning liquid in the perfusion box 1 is pressurized under the driving action of the motor 4, and then sent to the remote micro-axial blood pump 9 via the liquid outlet pipe 8 and the delivery pipe 901, so as to perform a synchronous cleaning operation on the micro-axial blood pump 9 during its operation. During the operation of the motor of the micro-axial blood pump 9, there will be heat, wear, and blood entering the gap between the impeller shaft and the bearing or the motor, which will cause damage to the blood pump. Therefore, by continuously and uniformly perfusing the blood pump with high-pressure cleaning liquid at a constant speed, the purpose of cleaning, cooling, and avoiding wear of the blood pump and blood entering and damaging the blood pump can be achieved at the same time. Among them, the cleaning liquid pressurized by the perfusion device will be filtered through the liquid filter 801 before being sent to the micro-axial blood pump 9 to ensure that impurities such as tiny particles will not enter the blood pump, and then the pressure will be monitored by the pressure sensor 802 to ensure that the perfused cleaning liquid meets the pressure requirements of the blood pump.

[0033] like Figure 8 The control device 10 includes a control module 120, which includes a main processor (MPU) 123, a motor drive circuit 121 and a signal processing circuit 122. The motor drive circuit 121, the signal processing circuit 122, the human-computer interaction module 110, and the sound and light alarm module 130 are connected to the main processor 123, the motor drive circuit 121 is connected to the motor 4, and the signal processing circuit 122 is connected to the pressure sensor 802. In addition, the control device 10 also includes a storage module 140, which is connected to the main processor 123.

[0034] In the present invention, the human-computer interaction module 110 is used to display the perfusion and cleaning information in real time (such as displaying the cleaning fluid pressure data detected by the pressure sensor 802 and the operating data of the motor 4 (such as the direction and speed)), display the alarm signal, and receive the relevant control instructions input by the user (such as setting the preset pressure value, the alarm pressure threshold, etc. through the human-computer interaction module 110). The motor drive circuit 121 is used to control the direction and speed of the motor 4. The signal processing circuit 122 is used to perform relevant processing (such as noise removal filtering, amplification, etc.) on the pressure signal (cleaning fluid pressure value) fed back by the pressure sensor 802. The main processor 123 is used to receive the pressure signal and send a motor control signal to the motor drive circuit 121 according to the pressure signal to increase or decrease the speed of the motor 4 to adjust the cleaning fluid pressure sent to the micro-axial blood pump 9. In addition, the main processor 123 also sends an alarm instruction to the sound and light alarm module 130 according to the pressure signal. The communication module 150 is used to communicate with external equipment or a control center. The storage module 140 is used to store information such as pressure signals, motor speeds, and alarms. The sound and light alarm module 130 is used to issue a timely alarm when the pressure signal monitored by the pressure sensor 802 reaches the alarm pressure threshold.

[0035] In practical applications, the control device 10 further includes a power module 160, which is used to provide power to each module, circuit, or device. Figure 1 The motor 4 is connected to the control module 120 or the motor driving circuit 121 through the driving control line 401 , and the pressure sensor 802 is connected to the control module 120 or the signal processing circuit 122 through the signal line 8021 .

[0036] In addition, if Figure 1 and Figure 8 The micro-axial blood pump 9 is connected to the control device 10 via a power control line 903. On the one hand, the power module 160 supplies power to the micro-axial blood pump 9 via the power control line 903. On the other hand, the micro-axial blood pump 9 receives instructions issued by the main processor 123 via the power control line 903 and operates according to the instructions.

[0037] In actual implementation, the delivery tube 901 can be designed as a double-lumen tube, the liquid outlet tube 8, the power control line 903 are connected to the hub 902, that is, they are merged through the hub 902, and the hub 902 is connected to the delivery tube 901, that is, the liquid outlet tube 8 is connected to one transmission cavity of the delivery tube 901 through the hub 902 and connected to the micro-axial blood pump 9, and the power control line 903 passes through the hub 902 and the other transmission cavity of the delivery tube 901 to connect to the micro-axial blood pump 9, to supply power to the micro-axial blood pump 9 and control its operation. The hub 902 is an existing component in the art.

[0038] In the present invention, the micro-axial blood pump 9 is an existing device in the art, and can be understood by referring to the "A kind of intra-aortic circulation assist device" disclosed in the Chinese utility model patent with publication number CN215585245U. The micro-axial blood pump 9 is a percutaneously delivered, catheter-mounted axial flow pump, which is located in the descending aorta when used. The core of the micro-axial blood pump 9 is a small rotating impeller installed in a self-expanding nitinol strut system. When the system is activated, the high-speed jet at its outlet accelerates the native aortic flow and entrains the blood flow to form a trans-aortic gradient. The micro-axial blood pump 9 is connected to the control device 10 via a thin and soft power control line 903.

[0039] In the present invention, the control module 120 monitors and adjusts the cleaning fluid pressure delivered to the delivery tube 901 during the operation of the motor 4. The cleaning fluid used to clean the micro axial flow blood pump 9 of the present invention includes but is not limited to heparin, glucose solution or sodium bicarbonate solution.

[0040] like Fig. 9In actual implementation, a preset pressure value is first obtained (the preset pressure value can be set through the human-computer interaction module 110), and the preset pressure value is the expected pressure value of the cleaning fluid delivered to the micro-axial blood pump 9. The motor 4 starts to pressurize the cleaning fluid. During the whole process, the pressure sensor 802 detects the pressure value of the cleaning fluid in real time and feeds it back to the main processor 123 after relevant processing by the signal processing circuit 122.

[0041] If the cleaning fluid pressure value detected by the pressure sensor 802 is too large and reaches the alarm pressure threshold, it is possible that the cleaning fluid will be blocked after being sent into the micro-axial blood pump 9, so the main processor 123 issues an alarm instruction to the sound and light alarm module 130 to sound and light alarm, reminding medical staff to check whether the pressure of the perfused cleaning fluid is too large and whether the pipeline is unobstructed to avoid unnecessary danger. Otherwise, continue to detect the cleaning fluid pressure.

[0042] The pressure sensor 802 feeds back the detected cleaning fluid pressure value to the main processor 123 in real time. The main processor 123 compares the difference between the preset pressure value and the measured cleaning fluid pressure value to see if it exceeds the set value. If it exceeds the set value, the motor drive circuit 121 controls the speed of the motor 4 to adjust the cleaning fluid pressure so that the measured cleaning fluid pressure value is equal to the preset pressure value, and then the motor 4 enters the holding mode and always keeps the speed at that time. Otherwise, the speed of the motor 4 is not adjusted, and the motor 4 keeps running at the original speed.

[0043] Furthermore, the present invention preferably adopts a PID algorithm to perform closed-loop control and regulation of the cleaning liquid pressure. Specifically, when the cleaning liquid pressure value in the liquid outlet pipe 8 (the measured cleaning liquid pressure value) is close to the preset pressure value, the speed of the motor 4 is slowly and uniformly adjusted until the measured cleaning liquid pressure value is equal to the preset pressure value, that is, when the cleaning liquid pressure value is close to the preset pressure value but less than the preset pressure value, the speed of the motor 4 is slowly and uniformly increased, and when the cleaning liquid pressure value is close to the preset pressure value but instantaneously greater than the preset pressure value, the speed of the motor 4 is slowly and uniformly reduced. By adjusting in this way, the measured cleaning liquid pressure value is finally stabilized at the preset pressure value.

[0044] When the motor 4 runs stably after the above adjustment, the flow rate in the delivery pipe 901 can be determined based on the speed of the motor 4. Specifically, the flow rate in the delivery pipe 901 is obtained by the following formula:

[0045] Q=A×v, where Q is the flow rate, A is the cross-sectional area of ​​the piston cylinder 6, and v is the displacement speed of the piston 5. There is a linear relationship between the rotation speed of the motor 4 and the displacement speed v, and the displacement speed v can be obtained through the rotation speed of the motor 4.

[0046] In the present invention, for example, the preset pressure value is set to 600 mmHg, the normal pressure range is set to 300 mmHg to 1100 mmHg, and the alarm pressure threshold is set to 1500 mmHg.

[0047] The advantages of the present invention are:

[0048] The present invention can provide continuous, uniform, and constant-pressure cleaning fluid when cleaning the micro-axial blood pump, thereby solving the problem of discontinuous and uneven perfusion of the cleaning fluid, and the piston is not prone to wear during operation. The continuous and uniform provision of the cleaning fluid ensures that blood does not enter the micro-axial blood pump, thereby ensuring the long-term stable and normal operation of the micro-axial blood pump. The cleaning fluid achieves the purpose of cleaning, cooling, and avoiding wear of the micro-axial blood pump, thereby improving the service life and working efficiency of the micro-axial blood pump.

[0049] The above are preferred embodiments of the present invention and the technical principles used therein. For those skilled in the art, any obvious changes such as equivalent transformations, simple replacements, etc. based on the technical solution of the present invention, without departing from the spirit and scope of the present invention, are within the scope of protection of the present invention.

Claims

1. A sustainable cleaning system for a micro axial flow blood pump, characterized in that: The invention comprises a liquid bottle, a perfusion device and a pressure sensor, wherein the liquid bottle is connected to the perfusion device via a liquid inlet pipe, the perfusion device is connected to one end of a delivery pipe via a liquid outlet pipe, the pressure sensor is installed on the liquid outlet pipe, the other end of the delivery pipe is used to communicate with a micro-axial blood pump, and a control device is connected to the perfusion device, the pressure sensor and the micro-axial blood pump, wherein: the perfusion device comprises a perfusion box, a driving cylinder is installed in the perfusion box, the piston of the driving cylinder is connected to a motor via a transmission assembly, and the piston is extended into and extended out of the driving cylinder by the transmission assembly under the drive of the motor. The driving cylinder performs reciprocating linear motion so that the cleaning fluid delivered from the liquid bottle is continuously and evenly delivered to the micro-axial blood pump after being pressurized by the driving cylinder; when the pressure sensor detects that the pressure value of the cleaning fluid is too large and reaches the alarm pressure threshold, an audible and visual alarm is triggered, otherwise the cleaning fluid pressure is continuously detected, wherein, when the cleaning fluid pressure value detected by the pressure sensor is not equal to the preset pressure value and the difference between the two exceeds the set value, the control device adjusts the cleaning fluid pressure by controlling the motor speed so that the cleaning fluid pressure value is equal to the preset pressure value, and the motor enters the holding mode, otherwise the motor maintains the original speed.

2. The sustainable cleaning system of the micro axial flow blood pump according to claim 1, characterized in that: A liquid medicine filter is installed on the liquid outlet pipe, and the liquid medicine filter is located between the pressure sensor and the perfusion device.

3. The sustainable cleaning system of the micro axial flow blood pump according to claim 1, characterized in that: The PID algorithm is used to adjust the cleaning liquid pressure value, wherein when the cleaning liquid pressure value in the liquid outlet pipe is close to the preset pressure value, the motor speed is slowly and uniformly adjusted until the cleaning liquid pressure value is equal to the preset pressure value.

4. The sustainable cleaning system of the micro axial flow blood pump according to claim 1, characterized in that: The driving cylinder comprises a piston cylinder and a piston. The interior of the piston cylinder is divided into a liquid inlet groove, a piston groove and a liquid outlet groove by two parallel partitions. The piston groove is located between the liquid inlet groove and the liquid outlet groove. A liquid inlet interface is provided on the side of the piston cylinder corresponding to the liquid inlet groove, and a liquid outlet interface is provided on the side of the piston cylinder corresponding to the liquid outlet groove. Two one-way valves are separately installed on each of the partitions, and the one-way valves only allow liquid to flow in one direction. Each of the one-way valves on one of the partitions is respectively opposite to a corresponding one of the one-way valves on the other partition and forms a pair. The inlet and outlet directions of each of the one-way valves are consistent. The piston rod of the piston is arranged through the piston cylinder, and the piston head at one end of the piston rod can be movably clamped between the two partitions and is in the piston groove. The other end of the piston rod extending out of the piston cylinder is provided with a driving end head, and the driving end head is connected to the motor via the transmission assembly. The piston head of the piston is driven by the transmission assembly by the motor to make reciprocating linear movements between the two pairs of one-way valves in the piston groove.

5. The sustainable cleaning system of the micro axial flow blood pump according to claim 4, characterized in that: A sealing ring is installed on the piston head, and a sealing ring is installed at the through hole of the piston cylinder where the piston rod passes through.

6. The sustainable cleaning system of the micro axial flow blood pump according to claim 4, characterized in that: The perfusion box is formed by buckling a top shell and a bottom shell, the transmission assembly includes a transmission shaft, the transmission shaft is connected to the output shaft of the motor via a coupling, a positioning member and a transmission gear are installed on the transmission shaft, the positioning member is rotatably installed on a positioning seat, the positioning seat is installed on the bottom shell of the perfusion box, one side of the driving end of the piston is provided with a rack belt for meshing with the transmission gear, and the other side of the driving end is placed on a guide seat installed on the bottom shell of the perfusion box, and the driving end of the piston moves linearly on the guide seat driven by the transmission gear.

7. The sustainable cleaning system of the micro axial flow blood pump according to claim 6, characterized in that: A side of the driving end head placed on the guide seat is concavely provided with a slide groove, and a limiting column is convexly provided on the limiting seat. The limiting column extends into the slide groove and is limited to move only within the slide groove.

8. The sustainable cleaning system of the micro axial flow blood pump according to claim 1, characterized in that: The positioning seat is composed of two outer groove plates with arc-shaped grooves which are separated and arranged side by side, and an intermediate groove plate between the two outer groove plates, wherein the arc-shaped groove area of ​​the intermediate groove plate is larger than the arc-shaped groove area of ​​the outer groove plates; the positioning member includes a positioning cylinder, wherein a convex ring is convexly provided at the middle part of the positioning cylinder, and the two ends of the positioning cylinder which are exposed from the convex ring are respectively placed on the two outer groove plates, and the convex ring is placed on the intermediate groove plate, and the convex ring is limited between the two outer groove plates and rotates on the intermediate groove plate.

9. The sustainable cleaning system of the micro axial flow blood pump according to claim 1, characterized in that: The control device includes a control module, which includes a main processor, a motor drive circuit and a signal processing circuit. The motor drive circuit, the signal processing circuit, the human-computer interaction module, and the sound and light alarm module are connected to the main processor, the motor drive circuit is connected to the motor, and the signal processing circuit is connected to the pressure sensor.

10. The sustainable cleaning system of the micro axial flow blood pump according to claim 1, characterized in that: The micro-axial blood pump is connected to the control device via a power control line, the delivery tube is a double-lumen tube, the liquid outlet tube and the power control line are connected to a hub, and the hub is connected to the delivery tube, wherein the liquid outlet tube is connected to a transmission cavity of the delivery tube via the hub and connected to the micro-axial blood pump, and the power control line passes through the hub, another transmission cavity of the delivery tube and is connected to the micro-axial blood pump.

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