JP2003033430A - Device for driving blood pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for driving a blood pump which obtains a high efficiency and a high responsiveness. SOLUTION: The device for driving the blood pump operates the blood pump 1 which carries out a first and second operations for blood so as to substitute for a cardiac function or assist it. A gas charging/discharging part 2 for driving the blood pump 1 is provided in the device for driving the blood pump. A movable member 24 is arranged in a hollow chamber 20 in the gas charging/ discharging part 2. In the end of a period where the movable member 24 in the gas charging/discharging part 2 is operated in the direction of an arrow X1, the operation of the movable member 24 is controlled for approaching the movable member 24 to the wall surface 21 of a hollow chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blood pump drive device for driving a blood pump (artificial heart pump, intra-aortic balloon pump, etc.) that substitutes or assists the heart function of a living body.

[0002]

2. Description of the Related Art Blood pumps (artificial heart pumps and intra-aortic balloon pumps) that substitute or assist the heart function of the living body.
It has been known. Furthermore, a blood pump drive device for driving this blood pump is provided. This device includes a gas supply / discharge section having a hollow chamber wall surface forming a hollow chamber and a diaphragm partitioning the hollow chamber into a gas chamber and a drive fluid chamber, and a drive fluid supplied to the drive fluid chamber of the gas supply / discharge section. And a drive unit having a function of discharging (Japanese Patent Laid-Open No. Sho 60).
-106462).

According to this, when the blood pump is an artificial heart pump that substitutes for the heart function, the drive unit supplies gas to the drive fluid chamber of the gas supply / exhaust unit to operate the diaphragm in one direction. By doing so, the chamber volume of the drive fluid chamber of the gas supply / discharge unit is increased and the chamber volume of the gas chamber of the gas supply / discharge unit is decreased. As a result, the blood pump is caused to perform the first operation via the gas supply / discharge unit, and thus the blood pump has a function of delivering blood to the living body.

Further, the reverse movement of the drive unit causes the gas to be discharged from the drive fluid chamber of the gas supply / exhaust unit to operate the diaphragm in the other direction, thereby increasing the volume of the gas chamber of the gas supply / exhaust unit and increasing the gas volume. The chamber volume of the drive fluid chamber of the supply / discharge unit is reduced. As a result, the blood pump is caused to perform the second operation via the gas supply / discharge unit, and thus the blood pump has a function of sucking blood of the living body.

[0005]

According to the blood pump drive device employing the above-described method, the pressure transmission using the diaphragm is favorably performed. However, in the above-described blood pump drive device, higher efficiency,
High responsiveness is required.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a blood pump drive device which is advantageous for achieving higher efficiency and higher responsiveness.

[0007]

The present inventor has been developing a blood pump drive device for many years. And, unlike a liquid that can be regarded as an incompressible fluid, the gas in the gas chamber of the gas supply / exhaust unit that drives the blood pump is a compressible fluid that is elastically compressed with pressurization. The present inventor has paid attention to the fact that it functions as a kind of elastic spring when viewed as a medium.

That is, the above-described blood pump drive device operates the movable member such as the diaphragm of the gas supply / discharge section in one direction to supply the gas in the gas chamber of the gas supply / discharge section to the blood pump. Is to drive. In this blood pump drive device, by moving a movable member such as a diaphragm of the gas supply / discharge section in one direction, the gas in the gas chamber of the gas supply / discharge section is supplied to the blood pump at each operation. Functions as a kind of elastic spring that is easily compressed. For this reason, the loss of power transmission energy is likely to occur due to the influence of the spring length of the elastic spring due to the gas in the gas chamber. However, if the movable member is operated so as to be as close to the hollow chamber wall surface as possible while maintaining the movable member in a non-contact state with the hollow chamber wall surface at the end of the process of operating the movable member of the gas supply / discharge section in one direction. Despite the fact that the same volume of gas is supplied to the blood pump, the amount of spring length of the elastic spring due to the gas in the gas chamber of the gas supply / exhaust part becomes smaller, and the loss of power transmission energy becomes smaller accordingly. The present inventor has paid attention.

Further, as described above, if the spring length of the elastic spring due to the gas in the gas chamber of the gas supply / discharge section is small, the loss of power transmission energy is small as compared with the case where the spring length is large. Therefore, even when the driving condition of the blood pump is changed, the moving stroke of the movable member of the gas supply / discharge unit and the driving operation of the blood pump are likely to have a correlation,
The present inventor has paid attention to the fact that stable driving with less loss of power transmission energy is possible. Then, based on such attention, the blood pump drive device according to the present invention was completed.

That is, a blood pump drive device according to the present invention is a blood pump drive device for driving a blood pump that performs a first operation and a second operation on blood in order to substitute or assist a heart function. A wall of the hollow chamber that forms a chamber, a gas chamber that accommodates gas and is connected to the blood pump and that supplies gas to the blood pump, and a drive fluid chamber that stores the drive fluid.
Supplying a drive fluid to the drive fluid chamber of the gas supply / discharge section, and a gas supply / discharge section having a movable member for varying the chamber volume of the gas chamber and the chamber volume of the drive fluid chamber for the second operation. And a function of discharging the gas, and by supplying the driving fluid to the driving fluid chamber of the gas supply / discharging portion to operate the movable member in one direction, the volume of the driving fluid chamber is increased and the volume of the gas chamber is increased. To reduce blood flow to the first
By performing the operation and sucking the driving fluid into the driving fluid chamber of the gas supply / exhaust portion to actuate the movable member in the other direction, the volume of the gas chamber of the gas supply / exhaust portion is increased and the gas supply / discharge Movable at the end of the process of reducing the volume of the drive fluid chamber of the unit and causing the blood pump to perform the second operation via the gas supply / discharge unit and the movable member of the gas supply / discharge unit in one direction. The present invention is characterized by comprising a control unit for controlling the operation of the movable member, aiming to bring the member closer to the wall surface of the hollow chamber.

According to the blood pump drive device of the present invention, the operation of the movable member is aimed at the purpose of bringing the movable member close to the wall surface of the hollow chamber at the end of the process of operating the movable member of the gas supply / discharge section in one direction. Is controlled. For this reason,
When the gas in the gas chamber is supplied to the blood pump, the elastic spring length of the gas in the gas chamber of the gas supply / exhaust part becomes longer than that in the case where the operation of the movable member ends near the middle of the hollow chamber at the end of the above process. The amount becomes smaller. Therefore, the loss of power transmission energy wasted by the compression of the gas in the gas chamber accompanying the operation of the movable member is reduced. Therefore, it is advantageous that the efficiency of the blood pump drive device can be improved and the high responsiveness of the blood pump drive device can be realized.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The following embodiments can be appropriately adopted as a blood pump drive device according to the present invention.

As the movable member of the gas supply / discharge section, a hollow chamber of the gas supply / discharge section is partitioned into a gas chamber and a driving fluid chamber, and a membrane member and a piston member can be exemplified. A diaphragm can be exemplified as the membrane member. The gas chamber of the gas supply and exhaust unit,
It means a chamber containing a gas for the first and second operations of the blood pump. The drive fluid chamber of the gas supply / exhaust unit is arranged to face the gas chamber via the movable member. As the gas chamber of the gas supply / discharge unit, when the chamber volume of the gas chamber becomes small, it becomes a positive pressure state with respect to atmospheric pressure, and when the chamber volume of the gas chamber becomes large, it becomes a negative pressure state. The embodiment which does can be adopted.

The control unit may adopt an embodiment having a movable member position determination means for directly or indirectly determining that the movable member operates in one direction and comes into contact with or approaches the wall surface of the hollow chamber. it can.

As the control unit, generally, a CPU can be used to form a software or a wired logic circuit can be formed to be a hardware.

An embodiment in which a sensor that detects the operating position of the movable member in the hollow chamber is used, and the movable member position determination means determines that the position of the movable member detected by this sensor has contacted or approached the wall surface of the hollow chamber. Can be adopted. Examples of this sensor include a magnetic sensor that magnetically detects the operating position of the movable member, a sensor such as a capacitance sensor that electrostatically detects the operating position of the movable member, and a sensor that detects infrared rays or laser light. can do. An embodiment in which the control unit determines that the movable member has contacted or approached the wall surface of the hollow chamber based on the detection signal of this sensor can be adopted.

First pressure detecting means for directly or indirectly detecting the pressure of the gas in the gas chamber of the gas supply / exhaust section, and directly or indirectly the pressure of the driving fluid in the driving fluid chamber of the gas supply / exhaust section. It is possible to adopt the embodiment in which the second pressure detecting means for detecting the above is provided. In this case, when the pressure of the drive fluid chamber of the gas supply / discharge unit detected by the second pressure detection unit is higher than the pressure of the gas chamber of the gas supply / discharge unit detected by the first pressure detection unit by a predetermined value, the movable The member position determination means can employ the embodiment in which it is determined that the movable member is in contact with or close to the wall surface of the hollow chamber. If the movable member abuts or approaches the wall surface of the hollow chamber in the direction in which the volume of the gas chamber of the gas supply / exhaust unit decreases, the change in the volume of the gas chamber of the gas supply / exhaust unit is restricted. Therefore, when the drive fluid is supplied from the drive unit to the drive fluid chamber of the gas supply / discharge unit, the pressure of the drive fluid chamber of the gas supply / discharge unit becomes higher than the pressure of the gas chamber of the gas supply / discharge unit by a predetermined value. . Thereby, the movable member position determination means can determine that the movable member has contacted or approached the hollow chamber wall surface. A pressure sensor can be exemplified as the first pressure detecting means and the second pressure detecting means.

When the movable member position determining means determines that the movable member of the gas supply / exhaust portion is operating in one direction and is in contact with or close to the wall surface of the hollow chamber, gas is supplied to the gas chamber of the gas supply / exhaust portion. An embodiment in which the control unit is provided with the intake control means for controlling the intake air can be adopted. When the amount of gas in the gas chamber of the gas supply / discharge unit is less than the optimum amount, the movable member contacts the wall surface of the hollow chamber.

Here, it is preferable to avoid frequent contact of the movable member with the wall surface of the hollow chamber. Therefore, if the movable member position determination means determines that the movable member operates in one direction and comes into contact with or approaches the wall surface of the hollow chamber, the intake control means sucks gas into the gas chamber of the gas supply / exhaust portion to replenish it. Then, the pressure in the gas chamber is increased by an appropriate amount. As a result, frequent contact of the movable member with the wall surface of the hollow chamber is avoided.

Exhaust control means for discharging the gas in the gas chamber of the gas supply / discharge section when the movable member position determining means does not detect that the movable member operates in one direction and comes into contact with or approaches the wall surface of the hollow chamber. The embodiment in which the control unit is provided can be adopted. When the movable member position determination means does not determine that the movable member operates in one direction and comes into contact with or approaches the wall surface of the hollow chamber, the amount of gas in the gas chamber of the gas supply / exhaust unit is excessive than the optimum amount. The control, which aims at bringing the movable member closer to the wall surface of the hollow chamber at the end of the process of operating the movable member in one direction, which is the main object of the present invention, becomes difficult to be executed. Therefore, when the movable member position determination means does not detect that the movable member operates in one direction and comes into contact with or approaches the wall surface of the hollow chamber, the exhaust control means discharges the excess gas in the gas chamber. This facilitates execution of the above control.

It is possible to adopt an embodiment in which an opening / closing valve is provided that connects the gas chamber of the gas supply / discharge section to the external atmosphere. In this case, when the pressure of the gas chamber of the gas supply and discharge unit is lower than the pressure of the external atmosphere of the gas chamber of the gas supply and discharge unit,
The intake control means may adopt an embodiment in which the on-off valve is opened to supply the gas (generally air) in the external atmosphere to the gas chamber of the gas supply / discharge section to replenish it. When the pressure of the gas chamber of the gas supply / exhaust unit is higher than the pressure of the external atmosphere, the exhaust control unit may adopt an embodiment in which the opening / closing valve is opened to exhaust the gas in the gas chamber to the external atmosphere. The pressure of the external atmosphere means the pressure of the atmosphere outside the blood pump drive device according to the present invention, and can be exemplified by the atmospheric pressure. When the blood pump drive device according to the present invention is installed in a flying object such as an airplane, the pressure of the external atmosphere may be lower than the atmospheric pressure. Depending on the surgery, the pressure of the external atmosphere may be slightly higher than the atmospheric pressure.

When the movable member position determination means does not determine within a specified time that the movable member of the gas supply / discharge unit operates in one direction and abuts or approaches the wall surface of the hollow chamber of the gas supply / discharge unit, the gas supply unit The amount of gas in the gas chamber of the discharge part is more excessive than the optimum amount, and at the end of the process of operating the movable member in one direction, which is the main feature of the present invention, the movable member is moved to the hollow chamber wall surface of the gas supply and discharge part. The goal is to get closer to
It becomes difficult to execute. Therefore, when the movable member position determination means does not determine that the movable member operates in one direction and abuts or approaches the wall surface of the hollow chamber within the specified time, the movable member is discharged by an appropriate amount of excess gas in the gas chamber. It is possible to adopt an embodiment in which the control unit includes a compulsory means for forcibly bringing the movable member into contact with or approaching the wall surface of the hollow chamber when operating in one direction. In this case, the gas in the gas chamber is forcibly discharged when the movable member position determination means does not determine that the movable member comes into contact with or approaches the wall surface of the hollow chamber of the gas supply / discharge unit within the specified time. As a result, when the movable member subsequently operates in one direction, the movable member comes into contact with or approaches the wall surface of the hollow chamber. The enforcement means can perform the above-mentioned control regularly or irregularly.

A pressure responsive portion that responds to changes in the gas pressure in the gas chamber that changes with the operation of the movable member, and a pressure response when the movable member operates in one direction and abuts or approaches the wall surface of the hollow chamber. An embodiment having a reference physical quantity setting unit that sets a physical quantity of a unit as a reference physical quantity can be adopted. In this case, (reference physical quantity + α1) to (reference physical quantity +
An embodiment may be adopted in which the control unit controls the operation of the movable member in the hollow chamber so that the physical quantity of the pressure response unit is maintained between α2). When the physical quantity of the pressure responsive portion falls within the predetermined range in this way, the operation of the movable member is further stabilized. α1 and α2 can be set arbitrarily. For example, α2 = 0 can be set. When α2 = 0, the control unit controls the operation of the movable member in the hollow chamber so that the physical quantity of the pressure response section is maintained between the reference physical quantity and the (reference physical quantity + α1).

The pressure responsive section may adopt an embodiment which is a pressure accumulating chamber having a pressure accumulating ability. The pressure accumulating chamber accumulates pressure when the movable member operates in the other direction such that the chamber volume of the gas chamber of the gas supply / exhaust unit increases and the chamber volume of the driving fluid chamber of the gas supply / exhaust unit decreases. Further, this pressure accumulating chamber releases pressure accumulation when the movable member operates in one direction so that the chamber volume of the gas chamber of the gas supply / exhaust unit decreases and the chamber volume of the driving fluid chamber of the gas supply / exhaust unit increases. Assists the operation of the movable member.

It is possible to adopt an embodiment in which the control section has a pressure accumulating chamber pressure detecting means for directly or indirectly detecting the pressure of the driving fluid in the pressure accumulating chamber. In this case, the embodiment in which the reference physical quantity setting unit is a pressure accumulation chamber reference pressure setting unit that sets the lowest pressure of the pressure accumulation chamber detected by the pressure accumulation chamber pressure detection unit as the pressure accumulation chamber reference pressure can be adopted. The minimum pressure of the pressure accumulating chamber corresponds to the state in which the movable member operates in one direction and is in contact with the wall surface of the hollow chamber. In this case, the control unit
The control unit adopts an embodiment for controlling the operation of the movable member in the hollow chamber so that the pressure of the pressure accumulating chamber is maintained between (accumulation chamber reference pressure + α1) and (accumulation chamber reference pressure + α2). You can When the pressure in the pressure accumulating chamber falls within the predetermined range in this way, the operation of the movable member is further stabilized. For example, an embodiment in which α2 = 0 can be adopted as in an example described later. When α2 = 0, the control unit controls the operation of the movable member in the hollow chamber so that the pressure in the pressure accumulating chamber is maintained between the pressure accumulating chamber reference pressure and (accumulation chamber reference pressure + α1). To do. Atmospheric pressure can be adopted as the reference pressure of the accumulator. A pressure sensor can be adopted as the pressure accumulating chamber pressure detecting means.

[0026]

Embodiments of the present invention will be specifically described below with reference to FIGS. The blood pump drive device according to the present embodiment is a fixed type or a movable type that can be carried and is installed in an operating room, and is for driving the blood pump 1 that is connected to a living body and performs the heart function of the living body. As shown in FIG. 1, the blood pump 1 includes a container 11 having a chamber 10.
And a second diaphragm 14 that functions as a blood supply / discharge member that partitions the chamber 10 into a blood chamber 12 and a gas drive chamber 13. The second diaphragm 14 is made of a flexible material such as rubber or resin as a base material, and the blood chamber 12 and the gas driving chamber 13 have variable chamber volumes. The gas drive chamber 13 is a chamber that stores air as gas. The blood chamber 12 is a chamber for containing blood, and has a spout 15 for supplying blood to a living body and an inlet 16 for sucking blood of the living body. The blood chamber 12 is connected to the living body side (for example, the aorta side of the living body) via the first check valve 15a that suppresses backflow and the outlet 15. The blood chamber 12 has a second check valve 1 for suppressing backflow.
It is connected to the living body side (for example, the atrium side of the living body) via 6a and the suction port 16.

As shown in FIG. 1, the blood pump drive device according to this embodiment has a first diaphragm 2 as a movable member.
Isolator 2 functioning as a gas supply / discharge unit having
And a liquid 44 as a driving fluid for the isolator 2.
A drive unit 4 having a function of supplying and discharging the liquid and a control unit 8 for controlling the operation of the blood pump drive device according to the present embodiment are provided.

As shown in FIG. 1, the isolator 2 includes a container 22 having a hollow chamber wall surface 21 forming a hollow chamber 20.
And a first diaphragm 24 as a movable member. The container 22 has a shape in which bowls having a pair of shapes are connected in reverse to each other. First diaphragm 24
Is the hollow chamber 20 of the container 22 and the first gas chamber 25 (gas chamber)
And a first driving fluid chamber 26 (driving fluid chamber), and is made of a flexible material such as rubber or resin as a base material.
The volume of the first gas chamber 25 and the first driving fluid chamber 26 is variable. The first gas chamber 25 is a chamber in which an appropriate amount of air as a gas is stored, and the gas drive chamber 1 of the blood pump 1
3 through the first passage 27.

As shown in FIG. 1, the drive unit 4 includes a pump 41 having a pump chamber 40, a motor 42 for driving the pump 41 via a transmission mechanism (not shown), and an oil reservoir 5 for containing a liquid 44. Have. The oil reservoir 5
A container 51 having a storage chamber 50, and a third movable member.
And a diaphragm 52. The third diaphragm 52 partitions the accommodation chamber 50 of the oil reservoir 5 into a second gas chamber 53 and a second driving fluid chamber 54 with a variable volume. A pressure accumulator 7 is provided in the second gas chamber 53 of the oil reservoir 5 via a fourth passage 56. The pressure accumulator 7 has a pressure accumulator 70 as a pressure response unit. Air is used as the gas contained in the pressure accumulating chamber 70 and the second gas chamber 53.

The pump chamber 40 of the pump 41 has a second passage 4
6 to communicate with the first drive fluid chamber 26 of the isolator 2 and the second passage of the oil reservoir 5 via the third passage 47.
It communicates with the drive fluid chamber 54. In the pump chamber 40, the first drive fluid chamber 26, and the second drive fluid chamber 54, as drive fluid,
A liquid 44, which is an incompressible driving fluid, is enclosed. Silicone oil is used as the liquid 44.

Now, when the motor 42 of the drive unit 4 is driven,
The pump 41 reciprocates. When the pump 41 operates in the forward direction, the liquid 44 in the pump chamber 40 is supplied to the first driving fluid chamber 26 of the isolator 2 via the second passage 46.
As a result, the first diaphragm 24 moves in the arrow X1 direction (blood ejection direction) so that the volume of the first drive fluid chamber 26 of the isolator 2 increases and the volume of the first gas chamber 25 of the isolator 2 decreases. Start to operate. As a result, the gas in the first gas chamber 25 of the isolator 2 is transferred to the first passage 27.
Is supplied to the gas drive chamber 13 of the blood pump 1 through the flow rate, and the volume of the gas drive chamber 13 of the blood pump 1 increases, and
The second diaphragm 14 of the blood pump 1 is actuated in the arrow Y1 direction so that the volume of the blood chamber 12 of the blood pump 1 becomes smaller. As a result, the blood chamber 1 of the blood pump 1
Blood 2 is supplied from the outlet 15 to the living body side (first operation). Thus, the first diaphragm 2 of the isolator 2 is
When the pump 4 operates in the direction of the arrow X1, the pump chamber 4
Since the liquid 44 of 0 flows into the first drive fluid chamber 26 of the isolator 2, the volume of the second drive fluid chamber 54 of the oil reservoir 5 decreases and the volume of the second gas chamber 53 of the oil reservoir 5 decreases. Is increased, the third diaphragm 52 of the oil reservoir 5 operates in the direction of the arrow W1. In this case, since the chamber volume of the second gas chamber 53 of the oil reservoir 2 increases, the pressure of the pressure accumulating chamber 70 decreases.

On the other hand, when the pump 41 operates in the reverse direction, the liquid 44 in the pump chamber 40 is supplied to the second driving fluid chamber 54 in the oil reservoir 5 via the third passage 47, and at the same time, in the first chamber of the isolator 2. 1 Liquid 44 in the driving fluid chamber 26
Is sucked into the pump chamber 40 through the second passage 46. As a result, the first diaphragm 24 moves toward the arrow X2 so that the volume of the first drive fluid chamber 26 of the isolator 2 decreases and the volume of the first gas chamber 25 of the isolator 2 increases.
Suction is performed in the direction (blood suction direction). As a result, the gas in the gas drive chamber 13 of the blood pump 1 is sucked into the first gas chamber 25 of the isolator 2 via the first passage 27, the chamber volume of the gas drive chamber 13 of the blood pump 1 is reduced, and the blood pump 1 The second diaphragm 14 of the blood pump 1 is suctioned in the direction of the arrow Y2 so that the volume of the blood chamber 12 is increased. As a result, the blood on the living body side is sucked into the blood chamber 12 through the suction port 16 of the blood pump 1 (second operation). The first operation and the second operation are executed alternately.

When the second diaphragm 14 of the blood pump 1 is sucked in the direction of the arrow Y2 as described above, the liquid 44 in the pump chamber 40 is charged in the oil reservoir 5 as described above.
Flowing into the second drive fluid chamber 54 of the oil reservoir 5, the volume of the second drive fluid chamber 54 of the oil reservoir 5 increases and the volume of the second gas chamber 53 of the oil reservoir 5 decreases. The third diaphragm 52 of the reservoir 5 is indicated by the arrow W.
Operates in two directions (accumulation direction). In this case, since the third diaphragm 52 is operating in the direction of the arrow W2, the pressure in the pressure accumulating chamber 70 becomes high and the pressure accumulating chamber 70 exerts a pressure accumulating action.

That is, the first diaphragm 24 is designed so that the volume of the first gas chamber 25 of the isolator 2 increases and the volume of the first driving fluid chamber 26 of the isolator 2 decreases.
When the suction operation is performed in the X2 direction (blood suction direction),
The pressure accumulating chamber 70 has a pressure accumulating function. Further, the first diaphragm 24 is actuated in the arrow X1 direction (blood ejection direction) so that the volume of the first gas chamber 25 of the isolator 2 decreases and the volume of the first driving fluid chamber 26 increases. At this time, the pressure accumulating chamber 70 releases the pressure accumulation to assist the stroke operation of the first diaphragm 24. In the case of pumping blood, the load is heavier than that of inhaling blood, but the assist allows the blood to be pumped well.

As shown in FIG. 1, the first isolator 2
In the gas chamber 25, the first opening / closing valve 33 is provided via the first intermediate passage 30.
It is connected. A second opening / closing valve 34 is connected to the pressure accumulating chamber 70 via the second intermediate passage 31. First on-off valve 33
The second opening / closing valve 34 is a normally closed type, and its port is opened only when necessary. The port of the first on-off valve 33 and the port of the second on-off valve 34 are in communication with the outside air as the outside atmosphere. By appropriately opening the second on-off valve 34, the pressure in the pressure accumulating chamber 70 can be adjusted.

The initial minimum pressure of the pressure accumulating chamber 70 is set to atmospheric pressure by using the second opening / closing valve 34 as follows. That is, the pump 41 is operated in the forward direction with the port of the second opening / closing valve 34 opened, and the liquid 4 in the pump chamber 40 is discharged.
4 is supplied to the first driving fluid chamber 26 of the isolator 2 through the second passage 46, and the first diaphragm 24 is operated in the arrow X1 direction (blood ejection direction) to abut the hollow chamber wall surface 21. As a result, the atmosphere flows into the pressure accumulating chamber 70 through the port of the second opening / closing valve 34. After that, the port of the second opening / closing valve 34 is closed. By doing so, the minimum initial pressure of the pressure accumulating chamber 70 becomes the atmospheric pressure.

The first gas chamber 25 of the isolator 2 is provided with a first sensor 36 as a first pressure detecting means for detecting the pressure of the first gas chamber 25. The first drive fluid chamber 26 of the isolator 2 is provided with a second sensor 37 as a second pressure detecting means for detecting the pressure of the first drive fluid chamber 26. The pressure accumulating chamber 70 is provided with a third sensor 38 as a pressure accumulating chamber pressure detecting means for detecting the pressure in the pressure accumulating chamber 70. The control unit 8 receives signals from the first sensor 36, the second sensor 37, and the third sensor 38 from the signal lines 36c and 3c.
7c, 38c, an input processing circuit for inputting, an output processing circuit for outputting a control signal to the first opening / closing valve 33, the second opening / closing valve 34 via signal lines 33c, 34c, RAM, ROM
Etc. and a CPU.

2 and 3 show pressure waveforms during use. 2 and 3, the horizontal axis represents time, and the vertical axis represents pressure (gauge pressure with atmospheric pressure of 0 mmHg). The waveform characteristic line A in FIGS. 2 and 3 indicates a change in the pressure of the first gas chamber 25 of the isolator 2 detected by the first sensor 36. In FIGS. 2 and 3, the waveform characteristic line B indicates the change in the pressure of the pressure accumulating chamber 70 detected by the third sensor 38. With the operation of the pump 41, as shown by the waveform characteristic line A in FIG. 2, the pressure in the first gas chamber 25 of the isolator 2 is increased in a pulse manner at almost every predetermined interval, and the blood pump 1 is caused to perform a heart function. . A1 indicates a region where the pressure P1 of the first gas chamber 25 of the isolator 2 is in a negative pressure state. Therefore, in FIGS. 2 and 3, time T1 to time T2 indicate a region in which the pressure P1 of the first gas chamber 25 is in the negative pressure state. Time T
From 0 to time T1, time T2 to time T3, the first gas chamber 25
Indicates a region in which the pressure P1 is higher than atmospheric pressure. As described above, the pressure P1 of the first gas chamber 25 alternately repeats positive pressure and negative pressure with the operation of the first diaphragm 24. 2 and 3, A2 is the first diaphragm 24.
2 shows the process of actuation by means of. A3 shows a process of suction operation by the first diaphragm 24.

As shown by the waveform characteristic line B in FIG. 2, the pressure (physical quantity) in the pressure accumulating chamber 70 increases and decreases like a triangular wave at almost every predetermined interval. B1 indicates a pressure increasing process of the pressure accumulating chamber 70. B2 shows the depressurization process of the accumulator 70. The minimum pressure of the accumulator 70 is
The standard is 0 mmHg, that is, atmospheric pressure. As can be understood from FIGS. 2 and 3, when the first diaphragm 24 of the isolator 2 is actuated in the arrow X1 direction, a maximum peak area Ap occurs around the final end of the actuation operation. The timing timing corresponds to the timing timing of the lowest pressure peak Bp of the pressure accumulating chamber 70. The reason is that the first diaphragm 24 of the isolator 2 has an arrow X1.
The third diaphragm 52 of the oil reservoir 5 is also operating in the direction of the arrow W1,
This is because the pressure in the pressure accumulating chamber 70 decreases accordingly. Appropriate means that it includes some changes in time. In this way, the pressure of the pressure accumulating chamber 70 changes in response to the pressure of the first gas chamber 25, so that it can function as a pressure responsive portion. Therefore, according to the present embodiment, the lowest pressure of the pressure P3 in the pressure accumulating chamber 70 is the arrow X1 at the first diaphragm 24 of the isolator 2.
It can be used as a standard of whether or not it operates in the direction and contacts the wall surface 21 of the hollow chamber.

In the normal driving state of the blood pump driving apparatus according to this embodiment, the first gas chamber 2 of the isolator 2 is
The pressure P1 of 5 and the pressure P2 of the first driving fluid chamber 26 of the isolator 2 correspond to each other, and the first diaphragm 2
In the state where 4 is not in contact with the hollow chamber wall surface 21, the pressure is substantially the same. However, even though the first diaphragm 24 of the isolator 2 comes into contact with the hollow chamber wall surface 21 and the volume of the first gas chamber 25 becomes substantially 0, the liquid 41 from the pump 41 is driven by the first drive of the isolator 2. When supplied to the fluid chamber 26, the pressure P2 of the first drive fluid chamber 26 is increased. Therefore, the pressure P2 of the first driving fluid chamber 26 detected by the second sensor 37 becomes higher than the pressure P1 of the first gas chamber 25 detected by the first sensor 36 by a predetermined value or more. Therefore, a differential pressure is generated between the gas pressure P1 in the first gas chamber 25 and the pressure P2 in the first driving fluid chamber 26.

When such a differential pressure is generated, it can be considered that the first diaphragm 24 of the isolator 2 contacts the hollow chamber wall surface 21 and the volume of the first gas chamber 25 becomes substantially zero. Waveform C in FIG. 2 means the generation of a differential pressure. According to the present embodiment, when the above-mentioned differential pressure is generated, the control unit 8 causes the first diaphragm 24 to contact the hollow chamber wall surface 21 of the container 22 of the isolator 2 and the first gas chamber 25.
It is determined that the volume of has become substantially zero.

When it is determined that the first diaphragm 24 operates in the direction of the arrow X1 and is in contact with the hollow chamber wall surface 21 as described above, the control unit 8 determines the lowest pressure of the pressure accumulating chamber 70 at that time. Set as reference pressure in memory. According to the present embodiment, the lowest pressure of the pressure accumulating chamber 70 is (accumulation chamber reference pressure +
The operation of the first diaphragm 24 is controlled so as to be maintained at a value between α2) and (accumulation chamber reference pressure + α1). Here, in the present embodiment, although α1 described above is a positive value,
Since α2 is set to 0, as a result, the lowest pressure of the pressure accumulating chamber 70 is maintained at a value between the pressure accumulating chamber reference pressure and (accumulation chamber reference pressure + α1).

According to this embodiment, the first isolator 2
The optimum amount of gas in the gas chamber 25 is such that at the end of the process in which the first diaphragm 24 is actuated in the arrow X1 direction, the hollow chamber wall surface 21 is kept in non-contact with the hollow chamber wall surface 21.
It means the amount of gas that is brought to the limit. Therefore,
When it is determined that the first diaphragm 24 is actuated in the direction of the arrow X1 and comes into contact with the wall surface 21 of the hollow chamber, the amount of gas in the gas chamber 25 that is not in contact with the wall surface 21 of the hollow chamber tends to be less than the optimum amount. Can be said. Therefore, when the pressure P1 of the first gas chamber 25 of the isolator 2 becomes lower than the pressure (= atmospheric pressure) of the external atmosphere, that is, the pressure P of the first gas chamber 25.
When 1 changes from the positive pressure state to the negative pressure state, the control unit 8 opens the port of the first opening / closing valve 33 for the set time Δt1. In FIG. 2, the command signal F1 means a command signal to the first on-off valve 33 that opens the port of the first on-off valve 33 for the set time Δt1. When the time when the pressure P1 of the first gas chamber 25 changes from the positive pressure to the negative pressure is T1, the command signal F1 to the first on-off valve 33 is controlled between the time T1 and the time T2 (negative pressure state). It is output by the unit 8.

Thus, the first gas chamber 2 of the isolator 2 is
If the amount of gas in 5 is less than the optimum amount, the first
When the gas chamber 25 is changed to a negative pressure, the port of the first opening / closing valve 33 is opened, so that the outside air passes through the port of the first opening / closing valve 33 and the outside air is the first gas chamber on the low pressure side (negative pressure side) of the isolator 2. 25 is automatically inhaled. As a result, the first gas chamber 25 of the isolator 2 is automatically replenished with gas, and when the first diaphragm 24 of the isolator 2 is subsequently actuated in the arrow X1 direction, the first diaphragm 24 is moved to the container 22 of the isolator 2. Although it approaches the wall 21 of the hollow chamber,
Contact with the wall surface 21 of the hollow chamber is suppressed.

Further, according to the present embodiment, when the control unit 8 does not determine that the first diaphragm 24 has come into contact with the hollow chamber wall surface 21 of the isolator 2 even if the first diaphragm 24 is actuated in the direction of the arrow X1, It can be said that the amount of gas in the one gas chamber 25 is more excessive than the optimum amount. Therefore, when the pressure P1 of the first gas chamber 25 of the isolator 2 becomes higher than the pressure (= atmospheric pressure) of the external atmosphere, that is, the pressure P of the first gas chamber 25.
When 1 becomes a positive pressure, the control unit 8 opens the port of the first opening / closing valve 33 for the set time Δt2. In FIG. 3, the command signal F2 causes the port of the first opening / closing valve 33 to have a set time Δt.
It means a command signal to the first on-off valve 33 that opens only 2. The command signal F2 is output when the pressure P1 of the first gas chamber 25 is a positive pressure. In this way, when the amount of gas in the first gas chamber 25 is in excess of the optimum amount, the isolator 2
When the first gas chamber 25 has a positive pressure higher than the atmospheric pressure, the port of the first opening / closing valve 33 is opened, so that excess air in the first gas chamber 25 of the isolator 2 is automatically transferred to the outside atmosphere. Will be discharged. As a result, when the first diaphragm 24 is subsequently actuated in the direction of the arrow X1, the first diaphragm 24 comes closer to or abuts the hollow chamber wall surface 21 of the container 22 of the isolator 2.

By the way, depending on the usage conditions, it may not be determined for a long time that the first diaphragm 24 is actuated in the direction of the arrow X1 and comes into contact with the hollow chamber wall surface 21 of the isolator 2. In this case, the amount of gas in the first gas chamber 25 of the isolator 2 is considerably excessive than the optimum amount, and in some cases, the first gas chamber 25 of the isolator 2 may be maintained as it is at a high pressure for a long period of time. is there. In this case, in the final stage of the control which is the main purpose of this embodiment, that is, "the first diaphragm 24 is brought into non-contact with the hollow chamber wall surface 21 at the end of the process of pulsating the first diaphragm 24 in the direction of the arrow X1. , Aiming to be as close as possible ”is difficult to execute.

Therefore, according to this embodiment, the isolator 2
When it is not determined within a specified time that the first diaphragm 24 of the above contact the wall surface 21 of the hollow chamber, the control unit 8
The port of the first on-off valve 33 is opened for the set time Δt3, and the excess gas in the first gas chamber 25 of the isolator 2 is forcedly discharged to the outside air. As a result, when the first diaphragm 24 of the isolator 2 is subsequently actuated in the direction of the arrow X1, the first diaphragm 24 is moved to the isolator 2
Is forcibly approached or brought into contact with the wall surface 21 of the hollow chamber. The times Δt1, Δt2, and Δt3 may have the same value or different values.

According to the present embodiment in which the above control is executed, the control is performed so that the minimum pressure P3 of the pressure accumulating chamber 70 is maintained between the pressure accumulating chamber reference pressure and the (accumulation chamber reference pressure + α1). The section 8 controls the ejection operation of the first diaphragm 24 in the hollow chamber 20 of the isolator 2. Therefore, the stability of the operation of the first diaphragm 24 is improved.

As described above, according to this embodiment, at the end of the process of activating the first diaphragm 24 of the isolator 2 in the direction of arrow X1, the first diaphragm 2 is released.
The operation of the first diaphragm 24 is controlled with the aim of bringing 4 closer to the wall surface 21 of the hollow chamber. Therefore, when the first diaphragm 24 is actuated in the arrow X1 direction (blood ejection direction) to supply the gas in the first gas chamber 25 to the gas drive chamber 13 of the blood pump 1, the first gas in the isolator 2 is generated. The amount of elastic spring length due to the gas in chamber 25 is reduced.
Therefore, the power transmission energy loss wastedly consumed by the compression of the gas in the first gas chamber 25 accompanying the operation of the first diaphragm 24 is reduced, and the efficiency of the blood pump driving device can be improved, and the blood pump driving can be achieved. It is advantageous to realize high responsiveness of the device.

Further, according to this embodiment, at the end of the process of pulsating the first diaphragm 24 of the isolator 2 in the direction of the arrow X1, the first diaphragm 24 is controlled so as to approach the wall surface 21 of the hollow chamber. Because
The volume of the first gas chamber 25 of the isolator 2 can be reduced while maintaining the gas supply capability of the isolator 2 to the blood pump 1.

(Flowchart) Typical examples of the above control modes are shown in FIGS. Hereinafter, this control mode will be described with reference to the flowcharts of FIGS. 4 and 5.
In FIG. 4, in step S102, the oil pump 4
By rotating 1 in the normal direction only,
The liquid 44 of 0 is supplied to the first drive fluid chamber 26 of the isolator 2, and the first diaphragm 24 of the isolator 2 is brought into contact with the wall surface 21 of the hollow chamber. When the first diaphragm 24 is in contact with the hollow chamber wall surface 21, the third diaphragm 52 of the oil reservoir 5 is moving in the direction of the arrow W1, so that the volume of the second gas chamber 53 of the oil reservoir 5 is large, and The pressure in the pressure accumulating chamber 70 is the lowest pressure.

Then, it is judged whether or not the first diaphragm 24 of the isolator 2 is in contact with the wall surface 21 of the hollow chamber (step S104). In this case, the pressure P2 of the first driving fluid chamber 26 of the isolator 2 is equal to the pressure P of the first gas chamber 25.
If the pressure difference exceeds a predetermined value greater than 1, it is determined that the first diaphragm 24 is in contact with the hollow chamber wall surface 21 of the isolator 2.

If it is determined that the first diaphragm 24 is in contact with the hollow chamber wall surface 21 of the isolator 2, the process proceeds to step S106, and the lowest pressure of the pressure accumulating chamber 70 at this time is set as the pressure accumulating chamber reference pressure. Thereafter, the pump 41 is repeatedly rotated in the forward and reverse directions to continue the pulsation operation of the first diaphragm 24 of the isolator 2 in the arrow X1 direction and the suction operation in the arrow X2 direction to repeat the pulsation of the isolator 2. Dynamic driving is started (step S10)
8).

In step S110, a timer for setting a specified time to be described later is started. This timer may be a software timer or an external timer. In step S112, pressure measurement of the first sensor 36, the second sensor 37, and the third sensor 38 is started. Furthermore, FIG.
As shown in FIG.
After 118, the process proceeds to step S120.

In step S120, it is determined whether or not the pressure P1 of the first gas chamber 25 of the isolator 2 measured by the first sensor 36 is higher than the pressure Pa (for example, 0 mmHg in gauge pressure), that is, the pressure of the first gas chamber 25. It is determined whether P1 is a positive pressure. If the pressure P1 is not positive pressure, the process waits until it becomes positive pressure. Pressure P1 of the first gas chamber 25 of the isolator 2
Is positive pressure, the process proceeds to step S122.

Then, in step S122, the pressure P1 of the first gas chamber 25 of the isolator 2 measured by the first sensor 36 and the first pressure of the isolator 2 measured by the second sensor 37 are measured.
The pressure P2 on the high pressure side of the drive fluid chamber 26 is used, and the value obtained by subtracting the pressure P1 from the pressure P2 on the high pressure side is Pb (for example, 100 m
mHg) is determined. In other words, the pressure P1 of the first gas chamber 25 and the pressure P of the first driving fluid chamber 26
It is judged whether or not there is a differential pressure exceeding a predetermined value with respect to 2.

If YES, that is, if there is a differential pressure exceeding a predetermined value, it means that the first diaphragm 24 is sufficiently in contact with the hollow chamber wall surface 21 of the isolator 2. In this case, the amount of gas in the first gas chamber 25 is determined to be less than the optimum amount.

Therefore, from step S122 to step S1
Proceeding to 40, the timer for setting a specified time, which will be described later, is reset and restarted. And step S142
At, the lowest pressure of the pressure P3 of the pressure accumulating chamber 70 measured by the third sensor 38 is reset as a new pressure accumulating chamber reference pressure.

Further, in step S144, the pressure P1 and the negative pressure Pc of the first gas chamber 25 measured by the first sensor 36 are measured.
(For example, the gauge pressure is −10 mmHg), and whether the pressure P1 is lower than the negative pressure Pc, that is, the pressure P1 <
It is determined whether or not there is a negative pressure Pc relationship. If NO, then YES
Wait until. If YES, the first gas chamber 25
Changes from positive pressure to negative pressure. Then step S14
It progresses from 4 to step S128, and opens the 1st opening valve 33 for the set time. As a result, the outside air having the atmospheric pressure is first introduced into the first gas chamber 25 in the negative pressure state of the isolator 2.
It is sucked from the port of the release valve 33 and replenished. Then, the process returns from step S128 to step S114. Therefore, the above steps S122 and S1
40 to step S144 and step S128 can function as an intake control means for replenishing the first gas chamber 25 of the isolator 2 with outside air when the amount of gas in the first gas chamber 25 is less than the optimum amount. it can. Step S
142 functions as a pressure accumulation chamber reference pressure setting unit (reference physical quantity setting unit) that newly sets the lowest pressure of the pressure P3 of the pressure accumulation chamber 70. In step S122, the first diaphragm 24 of the isolator 2 operates in the direction of the arrow X1 and the wall surface 2 of the hollow chamber 2
1 functions as a movable member position determination unit that determines that the movable member 1 is in contact with 1.

If NO in step S122, the amount of gas in the first gas chamber 25 is determined to be in excess of the optimum amount. Therefore, step S122
From step S124, the lowest pressure P3 of the pressure accumulating chamber 70 detected by the third sensor 38 and (pressure accumulating chamber reference pressure +
Compare with α1). In this control mode, the above α
2 is set to 0.

Then, in step S124, the pressure P3
Is larger than (accumulation chamber reference pressure + α1), the minimum pressure of the accumulator chamber 70 is higher than its optimum value (accumulation chamber reference pressure), and thus the amount of gas in the first gas chamber 25 of the isolator 2. Is more than the optimum amount, which means that the first diaphragm 24 of the isolator 2 is not in contact with the hollow chamber wall surface 21. Therefore, the process proceeds from step S124 to step S126, and the pressure P1 of the first gas chamber 25 measured by the first sensor 36 and the positive pressure Pd (for example, 15 mmHg in gauge pressure) are compared. If NO, wait until YES. If YES, the pressure P1 of the first gas chamber 25 has changed from a negative pressure to a positive pressure, which is more than the pressure Pd. Therefore, the process proceeds from step S126 to step S128, the port of the first opening valve 33 is opened for the set time, and the process returns to step S114. At this time, since the pressure P1 of the first gas chamber 25 is a positive pressure exceeding the atmospheric pressure, the excess air in the first gas chamber 25 is the first air.
It is automatically discharged to the outside air through the on-off valve 33. As a result, when the first diaphragm 24 is actuated in the direction of the arrow X1 next time, the first diaphragm 24 comes into contact with or approaches the hollow chamber wall surface 21.

Steps S122 to S1 described above
28 can function as an exhaust control means for discharging the excess gas in the first gas chamber 25 of the isolator 2 when the amount of gas in the first gas chamber 25 is in excess of the optimum amount. Further, steps S122 to S128 can function as means for maintaining the lowest pressure of the pressure accumulating chamber 70 of the pressure accumulating chamber between the accumulating chamber reference pressure and the (accumulating chamber reference pressure + α1).

Incidentally, even when the first diaphragm 24 of the isolator 2 is pulsatingly actuated in the direction of the arrow X1, it may not be judged within a prescribed time that the first diaphragm 24 of the isolator 2 is in contact with the hollow chamber wall surface 21 of the isolator 2. At this time,
The amount of gas in the first gas chamber 25 of the isolator 2 is considerably excessive than the optimum amount, and there is a possibility that the first gas chamber 25 will be kept in a high-pressure state for a long period of time. In this case, at the end of the process of operating the first diaphragm 24 in the direction of the arrow X1 which is the main purpose of this embodiment, the first diaphragm 24 is not in contact with the wall surface 21 of the hollow chamber, but is as close as possible to the target. The control becomes difficult to execute, which is not preferable.

Therefore, according to the present embodiment, step S11
At 4, it is determined whether or not the current time of the timer has exceeded the specified time of the timer. If the current time of the timer has not passed the specified time of the timer, the process directly proceeds from step S114 to step S120. If it has elapsed, the process proceeds to step S116, and the pressure P1 of the first gas chamber 25 measured by the first sensor 36 and the positive pressure Pf (for example, 15 mmHg in gauge pressure) are compared. If the pressure P1 is higher than the positive pressure Pf, the process proceeds from step S116 to step S118, the port of the first opening valve 33 is opened for the set time, and the process proceeds to step S120. Step S1
If NO in 16, wait until YES. As described above, when it is determined that the amount of gas in the first gas chamber 25 is excessively excessive, the first opening valve 33 is opened for the set time, so that the first gas chamber 25 of the isolator 2 is excessively excessive. The appropriate amount of gas is discharged to the outside air (external atmosphere) through the first opening / closing valve 33. Therefore, when the first diaphragm 24 is subsequently actuated in the direction of the arrow X1, the first diaphragm 24 comes into contact with the hollow chamber wall surface 21. Therefore, steps S114 to S11
8 can function as a compulsion means for forcibly abutting the first diaphragm 24 on the hollow chamber wall surface 21.

If the above-described control is executed, at the end of the process of pulsating the first diaphragm 24 of the isolator 2 in the direction of arrow X1, the first diaphragm 24 is released.
It is possible to control the operation of the first diaphragm 24 so that the first diaphragm 24 can be brought as close as possible while not contacting the wall surface 21 of the hollow chamber.

When the blood pump drive system according to this embodiment is used, the gas in the first gas chamber 25, the gas in the pressure accumulating chamber 70,
Thermal expansion / contraction of the liquid 44 in the pump chamber 40 may occur. Further, the driving condition of the blood pump 1 may change under the influence of changes in the living body. That is, the driving conditions of the blood pump driving device according to this embodiment may change. Even in such a case, step S1
14 to step S118, the first diaphragm 2
4 is forcibly and periodically brought into contact with the wall surface 21 of the hollow chamber. Further, when the first diaphragm 24 contacts the hollow chamber wall surface 21, the lowest pressure P3 of the pressure accumulating chamber 70 is reset as a new pressure accumulating chamber reference pressure as in steps S122 and S140 to S144. Then, the reset accumulator reference pressure and (reset accumulator reference pressure + α
The operation of the first diaphragm 24 is controlled so that the pressure P3 of the pressure accumulating chamber 70 is maintained between 1) and 1). Therefore, according to the present embodiment, even when the various driving conditions change as described above, at the end of the process of operating the "first diaphragm 24 in the direction of the arrow X1" which is the main feature of the present embodiment. While the first diaphragm 24 is not in contact with the wall surface 21 of the hollow chamber, it is possible to carry out the control aiming to make the first diaphragm 24 as close as possible.

According to the present embodiment, when the first diaphragm 24 is actuated in the direction of the arrow X1 and brought into contact with the hollow chamber wall surface 21, it is preferable that the pressure accumulating chamber 70 is at atmospheric pressure. This is the optimum amount of gas in the pressure accumulating chamber 70. Therefore, when it is determined that the first diaphragm 24 has actuated in the direction of the arrow X1 and has come into contact with the hollow chamber wall surface 21,
If the lowest pressure P3 of the pressure accumulating chamber 70 detected by the third sensor 38 is higher than the atmospheric pressure and the amount of gas in the pressure accumulating chamber 70 is in excess of this optimum amount, the second opening / closing valve 34 The port is opened to discharge the excess gas in the pressure accumulating chamber 70.
In addition, when it is determined that the first diaphragm 24 is actuated in the direction of the arrow X1 and comes into contact with the wall surface 21 of the hollow chamber, the pressure P3 of the accumulator 70 detected by the third sensor 38 is detected.
Is lower than the atmospheric pressure and the amount of gas in the pressure accumulating chamber 70 is less than the optimum amount, the second opening / closing valve 34
Open the port to open the outside air (outside atmosphere) gas first
The gas chamber 25 is replenished. As a result, the pressure P of the accumulator 70
The minimum pressure of 3 is atmospheric pressure.

(Other Embodiments) FIG. 6 shows another embodiment.
This embodiment has basically the same configuration as that of the above-described embodiment and has the same effect. Therefore, common reference numerals are given to parts having common functions. Hereinafter, description will be made focusing on parts different from the above-described embodiment. In this embodiment, the first sensor 36M is a sensor such as a magnetic sensor or an electrostatic sensor. Similarly, the second sensor 3
7M is a sensor such as a magnetic sensor or an electrostatic sensor. The first diaphragm 24 of the isolator 2 is equipped with members detected by these sensors.

Therefore, when the first diaphragm 24 of the isolator 2 operates in the directions of the arrows X1 and X2, the first diaphragm 2 is moved by the first sensor 36M and the second sensor 37M.
The current position of No. 4 is detected, and accordingly, it is detected that the first diaphragm 24 is in contact with or close to the hollow chamber wall surface 21.

Therefore, also in this embodiment, as in the case of the above-described embodiment, when the gas in the first gas chamber 25 is excessive, the excessive gas in the first gas chamber 25 of the isolator 2 is changed to the excessive gas. The gas can be discharged from the first on-off valve 33, or when the gas in the first gas chamber 25 of the isolator 2 is insufficient, the gas can be replenished from the first on-off valve 33 to the first gas chamber 25. . Therefore, also in this embodiment,
At the end of the process of pulsating the first diaphragm 24 of the isolator 2 in the direction of the arrow X1, the first diaphragm 24 can be controlled so as to be as close as possible to the hollow chamber wall surface 21 while not being in contact therewith.

(Others) In the above-described embodiment, the blood pump 1 which is a substitute for the heart function is adopted as the blood pump 41, but the present invention is not limited to this, and a balloon pump for assisting the heart function may be used. In the above-described embodiment, the operation in which the blood in the blood chamber 12 of the blood pump 1 is supplied from the outlet 15 to the living body side is the first operation, and the blood on the living body side is supplied from the suction port 16 of the blood pump 1 to the blood chamber. Although the operation sucked into 12 is the second operation, the first operation and the second operation may be reversed.

Although the liquid 44 is enclosed in the pump chamber 40 of the pump 41, it may be a gas such as air depending on the case. Further, the control mode according to the present embodiment is shown in FIGS.
The flow chart shown in FIG. In addition, the present invention is not limited to the embodiments described above and shown in the drawings. For example, the shapes and structures of parts, the order of flow charts, etc. are not limited to the embodiments described above, and deviate from the gist. It can be implemented by appropriately changing it within the range not to do.

[0073]

According to the blood pump drive device of the present invention, the goal is to bring the movable member close to the wall surface of the hollow chamber at the end of the process of operating the movable member of the gas supply / discharge section such as an isolator in one direction. , The operation of the movable member is controlled. Therefore, as described above, as compared with the case where the operation of the movable member ends near the middle of the hollow chamber at the end of the above process, the amount of the elastic spring length due to the gas in the gas chamber of the gas supply / exhaust portion becomes smaller. Therefore, the loss of power transmission energy wasted by the compression of the gas in the gas chamber due to the operation of the movable member is reduced accordingly.

Further, as described above, when the spring length of the elastic spring due to the gas in the gas chamber of the gas supply / discharge section is small, the loss of power transmission energy is small as compared with the case where the spring length is large. Therefore, even when the driving condition of the blood pump is changed, the moving stroke of the movable member of the gas supply / discharge unit and the driving operation of the blood pump are likely to have a correlation,
Stable driving becomes possible. Therefore, the blood pump drive device according to the present invention is advantageous in achieving higher efficiency and higher responsiveness.

Further, according to the blood pump drive device of the present invention, the control is performed with the goal of bringing the movable member closer to the wall surface of the hollow chamber at the end of the process of operating the movable member of the gas supply / discharge section such as the isolator in one direction. Therefore, it is possible to reduce the volume of the gas chamber of the gas supply / discharge unit while maintaining the gas supply capability of the gas supply / discharge unit to the blood pump.

[Brief description of drawings]

FIG. 1 is a configuration diagram schematically showing the entire apparatus.

FIG. 2 is a graph showing a pressure waveform of a first gas chamber and a pressure waveform of a pressure accumulating chamber.

FIG. 3 is a graph showing a pressure waveform of a first gas chamber and a pressure waveform of a pressure accumulating chamber.

FIG. 4 is a flowchart showing a typical control mode.

FIG. 5 is a flowchart showing a typical control mode.

FIG. 6 is a configuration diagram schematically showing an entire apparatus according to another embodiment.

[Explanation of symbols]

In the figure, 1 is a blood pump, 12 is a blood chamber, 14 is a second diaphragm, 2 is an isolator (gas supply / exhaust part), 20 is a hollow chamber, 21 is a hollow chamber wall surface, 24 is a first diaphragm (movable member), 25 is a first gas chamber (gas chamber), 26 is a first driving fluid chamber, (driving fluid chamber), 33 and 34 are on-off valves, 36
Is a first sensor (first pressure detecting means), 37 is a second sensor (second pressure detecting means), 38 is a third sensor (accumulation chamber pressure detecting means), 4 is a drive unit, 40 is a pump chamber, 41 is A pump, 44 is a liquid (driving fluid), 70 is a pressure accumulator (pressure response part), and 8 is a control part (movable member position determination means, intake control means, exhaust control means, accumulator reference pressure setting part).

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 3H045 AA02 AA08 AA12 AA22 BA19                       CA01 DA24 EA34                 3H077 AA07 CC02 CC09 DD09 DD14                       EE02 EE15 FF45 FF55                 4C077 AA04 DD02 DD04 DD09 FF04                       HH07 HH13 JJ06 JJ07 JJ13                       JJ19 KK23 KK27

Claims (9)

[Claims] 1. A blood pump drive device for driving a blood pump that performs a first operation and a second operation on blood in order to substitute or assist a heart function, wherein a hollow chamber wall surface forming a hollow chamber and gas are For the first operation and the second operation, the hollow chamber is partitioned into a gas chamber that is housed and is connected to the blood pump and supplies gas to the blood pump, and a driving fluid chamber that houses a driving fluid. A gas supply / discharge unit having a movable member for varying the chamber volume of the gas chamber and the chamber volume of the drive fluid chamber, and a function of supplying and discharging drive fluid to / from the drive fluid chamber of the gas supply / discharge unit. And driving the movable member in one direction by feeding a driving fluid to the driving fluid chamber of the gas supply / discharge section to increase the chamber volume of the driving fluid chamber and the chamber volume of the gas chamber. Reduced And causing the blood pump to perform the first operation via the gas supply / discharge unit, and discharging the drive fluid from the drive fluid chamber of the gas supply / discharge unit to operate the movable member in the other direction. And increase the chamber volume of the gas chamber of the gas supply / exhaust unit and reduce the chamber volume of the drive fluid chamber of the gas supply / exhaust unit, and perform the second operation on the blood pump via the gas supply / exhaust unit. And a control unit for controlling the operation of the movable member with the goal of bringing the movable member closer to the wall surface of the hollow chamber at the end of the process of operating the movable member in one direction. A blood pump drive device characterized by the above. 2. The control unit according to claim 1, wherein the control unit directly or directly determines that the movable member of the gas supply / discharge unit is actuated in one direction and abuts or approaches the wall surface of the hollow chamber of the gas supply / discharge unit. A blood pump drive device having a movable member position determination means for indirectly determining. 3. The first pressure detecting means for directly or indirectly detecting the pressure of the gas in the gas chamber of the gas supply / discharge section, and the driving fluid in the drive fluid chamber of the gas supply / discharge section according to claim 2. Second pressure detecting means for directly or indirectly detecting the pressure of the gas, and the movable member position determining means is configured to detect the gas in the gas supply / discharge section detected by the first pressure detecting means. When the pressure of the drive fluid chamber of the gas supply / discharge section detected by the second pressure detection means is higher than the pressure of the chamber by a predetermined value, it is determined that the movable member comes into contact with or approaches the wall surface of the hollow chamber. A blood pump drive device characterized by the above. 4. The gas control system according to claim 2, wherein when the movable member position determination means determines that the movable member has actuated in one direction to come into contact with or approach the wall surface of the hollow chamber. The movable member position determination means is provided with an intake control means for supplying gas to the gas chamber of the supply / discharge section, and the movable member position determination means indicates that the movable member operates in one direction and abuts or approaches the wall surface of the hollow chamber. A blood pump driving device, comprising: an exhaust control unit that discharges gas in the gas chamber of the gas supply / discharge unit when not detecting. 5. The on-off valve for communicating the gas chamber of the gas supply / exhaust portion with the external atmosphere of the gas chamber according to claim 4, wherein the intake control means includes a gas for the gas supply / exhaust portion. When the chamber pressure is lower than the pressure of the external atmosphere,
The on-off valve is opened to suck the gas in the external atmosphere into the gas chamber, and the exhaust control means is configured such that the pressure of the gas chamber of the gas supply / discharge unit is higher than the pressure of the external atmosphere of the gas chamber. At this time, the on-off valve is opened to discharge the gas in the gas chamber to the external atmosphere, the blood pump drive device. 6. The movable member position determining means according to claim 2, wherein the movable member position determining means does not determine that the movable member operates in one direction and abuts or approaches the wall surface of the hollow chamber within a predetermined time. A blood for discharging the gas from the gas chamber and forcing the movable member to come into contact with or approach the hollow chamber wall surface when the movable member operates in one direction. Pump drive. 7. The pressure responsive unit that responds to a change in the gas pressure in the gas chamber of the gas supply / discharge unit that changes with the operation of the movable member, and the movable member operates in one direction. And a reference physical quantity setting unit that sets a physical quantity of the pressure response unit when coming into contact with or approaching the wall surface of the hollow chamber as a reference physical quantity, and the control unit includes (reference physical quantity + α1) to (reference physical quantity +
A blood pump driving device, wherein the operation of the movable member in the hollow chamber is controlled so that the physical quantity of the pressure responsive portion is maintained during α2). 8. The pressure response unit is a pressure accumulating chamber according to claim 7, wherein the pressure accumulating chamber increases the volume of the gas chamber of the gas supplying / discharging unit and increases the volume of the driving fluid chamber of the gas supplying / discharging unit. Pressure is accumulated when the movable member operates in the other direction so that the chamber volume decreases, and the chamber volume of the gas chamber of the gas supply / discharge unit decreases and the chamber volume of the drive fluid chamber of the gas supply / discharge unit decreases. A blood pump drive device, wherein when the movable member operates in one direction so as to increase, accumulated pressure is released to assist the operation of the movable member. 9. The control unit according to claim 8, wherein the control unit has pressure-accumulation chamber pressure detection means for directly or indirectly detecting the pressure of the pressure-accumulation chamber, and the reference physical quantity setting unit detects the pressure-accumulation chamber pressure. A pressure accumulation chamber reference pressure setting unit that sets the lowest pressure of the pressure accumulation chamber detected by the means as a pressure accumulation chamber reference pressure, wherein the control unit is (accumulation chamber reference pressure + α1) to (accumulation chamber reference pressure + α2). A blood pump drive device, wherein the operation of the movable member in the hollow chamber of the gas supply / discharge unit is controlled so that the pressure in the pressure accumulating chamber is maintained during the period.