JP2001090687A - Blood pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disposable blood pump having a magnet housing chamber which can be recycled. SOLUTION: This blood pump is provided with a blood contact part provided with a pump chamber for sucking and discharging the blood with rotation of an impeller, a rotary shaft inserted into a rotary shaft insertion hole opened in a bottom surface of the pump chamber, and a drive part having a driving shaft connected to a terminal provided at a side opposite to a side, to which the impellers of the rotary shaft is fixed, freely to be removed and formed in the bottom surface of the pump chamber freely to be removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a blood pump, and more particularly, to a disposable blood pump.
The present invention relates to a blood pump capable of reducing the amount of waste by reusing some parts such as magnets for rotating an impeller.

[0002]

2. Description of the Related Art A centrifugal blood pump that sucks and discharges blood by rotating an impeller rotatably housed in a pump chamber temporarily replaces the function of the patient's heart in, for example, an ICU. It is widely used to help or temporarily assist the function of the patient's heart.

In the blood pump, the impeller is generally rotated by a drive unit provided outside.

Here, since the blood of the patient flows inside the centrifugal blood pump, the inside of the blood pump needs to be sterile. Further, the blood pump comprises:
Since it is often used in the ICU on the side of a patient undergoing intensive care or surgery, it is desirable that the number of bacteria outside the blood pump be low.

[0005] As such a blood pump, a pump chamber capable of discharging introduced blood by rotating an impeller and a rotating magnet device integrally connected to the pump chamber. A magnet housing chamber having a rotating body with a magnet mounted thereon, a rotating shaft inserted through a rotating shaft hole provided on the bottom surface of the pump chamber, and connecting the impeller and the rotating body; and the rotating shaft. A blood pump having a seal member for sealing between the hole and the rotating shaft has been used.

[0006]

In the blood pump, disposables are generally used for the purpose of preventing blood contamination due to reuse. However, the pump chamber and the magnet chamber cannot be separated. Therefore, the blood pump was discarded with the magnet attached.

Here, since blood and the like adhere to the discarded medical waste including the blood pump, it is general to incinerate the medical waste in order to prevent contamination by the blood and the like. It is a target.

In the above blood pump, the pump chamber, the impeller, the seal member, and the magnet housing chamber are usually made of plastic, so that they can be incinerated. However, the usual magnet is a non-combustible material, and thus has a problem that it remains as ash after the blood pump is incinerated.

An object of the present invention is to provide a disposable blood pump that solves the above-mentioned problems.

[0010]

According to the present invention, there is provided a pump chamber for discharging introduced blood by rotating an impeller having a rotary shaft.
The present invention relates to a blood pump characterized by comprising a magnet housing chamber which is detachably formed in the pump chamber and has a built-in rotating body in which a magnet is mounted so as to be rotatable by a rotating magnet device.

In a preferred embodiment of the present invention, for example,
The rotating shaft is inserted into a rotating shaft insertion hole formed in a bottom surface of the pump chamber, which is a wall surface facing the magnet housing chamber, and a tip end thereof is detachably formed at a rotation center of the rotating body. A blood pump, and an internal seal member attached to the rotating shaft, which diverges toward the rotating shaft insertion hole in the pump chamber,
A blood pump or the like having an external seal member attached to the rotary shaft, which diverges toward the rotary shaft insertion hole outside the pump chamber.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Specific Example FIG. 1 shows an example of the blood pump of the present invention.

As shown in FIG. 1, the blood pump of Example 1 is detachable from a pump chamber 1 for discharging introduced blood by rotating an impeller having a rotating shaft, and a bottom face of the pump chamber 1. And a magnet accommodating chamber 3 that is coupled to the

The pump chamber 1 has a casing B and an impeller A rotatably housed inside the casing B.

The casing B has an opening at one end, and a casing body B1 having a conical shape that is reduced from the opening end to the other end, and is screwed into an inner periphery of the opening in the casing body B1, A casing cover B2 for covering the opening.

The casing body B1 is provided with a blood suction pipe B11 at its top, that is, at the tip of the conical casing body B1, in a direction away from the casing cover B2, near the opening on the side surface of the casing body B1. , Tangentially, blood discharge tube B
12 is provided. Therefore, the casing body B1
Can have a funnel shape as a whole. A groove is formed in a circumferential direction in a portion near the opening on the outer peripheral surface of the casing body B1.

The surface of the casing cover B2 on the casing body B1 side is a short, substantially conical surface slightly projecting toward the top of the casing body B1.
The surface opposite to the casing body B1 is formed in a substantially planar shape. At the center of the casing cover B2,
The bearing mounting hole B21 is open. An enlarged portion B22 having a diameter larger than the diameter of the bearing mounting hole B21 and a predetermined depth is formed at an end of the bearing mounting hole B21 on the casing body B1 side. A bearing B3 is fitted to an end of the bearing mounting hole B21 opposite to the enlarged portion B22. A washer-shaped seal member D1 is fitted in the enlarged portion B22.

A pump chamber 1 is formed by the casing body B1 and the casing cover B2, and a bottom surface of the pump chamber 1 is formed by the casing cover B2. The casing body B1 and the casing cover B
Between them, a packing B4 for preventing blood from leaking outside is mounted. An impeller A is rotatably accommodated in the pump chamber 1.

The impeller A includes a turntable A1 formed in a conical shape, in other words, an umbrella shape, and the turntable A1.
The surface on the side protruding in a conical shape, that is, the surface on the front side, in other words, the surface of the truncated cone, is provided with an appropriate number of blades A2, e.g. . Further, the impeller A has a plurality of liquid flow through holes A3 near the center of rotation. The liquid flow through hole A3 is formed in a mortar-shaped space inside the turntable A1, in other words, the surface on the back side of the turntable A1 and the pump chamber 1
Blood that has entered the space formed between
The blood escapes to the front side of the turntable A1, thereby preventing the blood from staying in the space inside the turntable A1 and preventing the blood from coagulating.

The impeller A is housed inside the casing B such that the back surface of the turntable A1 faces the casing cover B2, that is, the bottom surface of the pump chamber 1.

One end of the rotating shaft 2 is fixed to the center of the back surface of the turntable A1, that is, the surface opposite to the side on which the blades A2 are provided. The rotating shaft 2
Is inserted through an opening at the center of the seal member D1 fitted in the enlarged portion B22, and is rotatably held by the bearing B3. Therefore, the opening of the seal member D1 forms a part of the rotary shaft insertion hole in the present invention.

A V-ring D2, which is an example of an internal seal member according to the present invention, is fitted between the turntable A1 and the seal member D1 on the rotary shaft 2, and is provided between the bearing B3 and the seal member D1. A V-ring D3, which is an example of the external seal member of the present invention, is fitted. Each of the V-rings D2 and D3 has a V-shaped cross-sectional shape,
It has a substantially cylindrical mounting portion to be mounted on the rotating shaft 2 and a conical enlarged lip portion that widens toward the seal member D1. The V-rings D2 and D3 are fitted to the rotating shaft 2 such that only the tip of the enlarged lip portion contacts the seal member D1. Therefore, pump chamber 1
When the internal and external pressures are balanced, the friction between the V-rings D2 and D3 and the seal member D1 is extremely small, so that the rotating shaft 2 has a small rotational resistance and the rotation is extremely smooth. Moreover, even when the pressure inside the pump chamber 1 rises or falls abnormally, the V-ring D2
And the enlarged lip on one of the V-rings D3 is pressed by the seal member D1, so that leakage of blood from inside the pump chamber 1 and entry of air into the pump chamber 1 can be effectively prevented.

As shown in FIG. 2A, a plug portion 21 having a substantially columnar shape is formed at the end of the rotary shaft 2 opposite to the side fixed to the turntable A1. I have. The plug portion 21 has an outer diameter that is substantially the same as the outer diameter of the rotating shaft 2. On the outer peripheral surface of the plug portion 21, four spherical concave portions 22 which are depressed in a spherical shape are formed at equal intervals on a circumference which goes around the outer peripheral surface.

A reduced portion 23 having a diameter slightly smaller than that of the plug portion 21 is formed at the tip of the plug portion 21. A step is formed between the plug part 21 and the reduction part 23. A groove 24 is formed in a circumferential direction on a side of the plug portion 21 opposite to a side on which the reduced portion 23 is formed.

On the bottom surface of the pump chamber 1, a magnet housing chamber 3 is detachably formed. The magnet housing chamber 3 is formed by a bottomed cylindrical rotating body housing case C4 having a short axial length and the casing cover B2.

A flange-like portion C41 is formed outwardly at the open end of the rotating body housing case C4. A casing body B1 is provided on an outer peripheral portion of the flange-shaped portion C41.
Is formed, and a protrusion that is screwed into the groove in the casing body B1 is formed at the top of the protrusion toward the inside. A groove is formed in a circumferential direction at a position where the opening end of the casing body B1 abuts on the flange-shaped portion C41,
An O-ring C42 is fitted in the groove.

Inside the magnet housing chamber 3, a disk-shaped rotor portion C1, a substantially cylindrical hub portion C2 fixed to the center of the rotor portion C1, and the casing cover B2 of the rotor C1 are provided. A rotating body 5 including a permanent magnet C3 fixed to a surface on the opposite side to the above, and a drive shaft 4 fixed along the rotation center of the hub portion C2 while penetrating the center of the hub portion C2. Is housed.

One end of the drive shaft 4 is connected to a bearing C5 provided at the center of the bottom surface of the rotating body housing case C4.
Is supported by Therefore, the rotating body 5
The drive shaft 4 in the magnet housing chamber 3
Rotate around.

At the end of the drive shaft 4 opposite to the side supported by the bearing C5, a joint 40 to which the rotary shaft 2 is detachably connected is formed.

FIG. 2 shows the structure of the joint 40. FIG.
The same reference numerals in FIG. 1 denote the same elements as those shown in FIG.

FIG. 2A is a partial cross-sectional view showing a configuration near the joint 40 in a state where the drive shaft 4 and the rotary shaft 2 are separated. As shown in FIG. 2A, the joint 40 is a so-called rectangular coupler type joint, is pierced along the axis of the drive shaft 4, and is larger than the outer diameter of the plug portion 21 of the rotary shaft 2. It has a socket portion 41 which is a circular bottomed hole having a slightly larger inner diameter. On the inner peripheral surface of the socket portion 41, four spherical projecting portions 42 projecting in a spherical shape are formed at equal intervals on a circle surrounding the inner peripheral surface. On the other hand, near the bottom surface of the socket portion 41, a first O-ring fitting groove 43 is formed in the circumferential direction. The first O-ring fitting groove 43 has O
A ring 45 is fitted.

On the other hand, outside the joint 40, the cylindrical member 4
4 is fitted. The end of the cylindrical member 44 on the opening side of the socket portion 41 is
, In other words, protruding from the end surface of the drive shaft 4. An inner wall of the protrusion of the cylindrical member 44;
An O-ring 46 having an outer diameter and a thickness larger than that of the O-ring 45 is fitted in a recess formed by the opening end of the socket 41.

FIG. 2B is a partial sectional view showing a state in which the rotating shaft 2 and the driving shaft 4 are connected. In FIG. 2B, the rotating shaft 2 is indicated by a broken line.

As shown in FIG. 2B, when the rotating shaft 2 and the driving shaft 4 are connected, the plug portion 21 of the rotating shaft 2 is inserted into the socket portion 41 of the joint 40, Spherical projection 4 on socket 41
2 fits into the spherical concave portion 22 of the plug portion 21. Then, the reduced portion 23 of the plug portion 21 is fitted into the inner periphery of the O-ring 45. On the other hand, since the O-ring 46 is restricted from the outside by the cylindrical member 44 so that the outer diameter does not increase, the O-ring 46 fits into the groove 24 of the plug portion 21 with appropriate hardness. Thereby, the plug part 21 is connected to the socket part 4.
1, the rotation shaft 2 and the drive shaft 4 are integrally connected.

When a force is applied in a direction to separate the rotary shaft from the drive shaft 4, the O-ring 46
4 receives an external force from a portion adjacent to 4 and elastically deforms outward. Similarly, the spherical protrusion 42 receives an outward force from the spherical recess 22 and elastically deforms outward.
As a result, as shown in FIG.
Is separated from the rotating shaft 2.

Here, as described above, the rotating body 5 is
, The drive shaft 4 forms the rotation center of the rotating body 5. Therefore, the rotating shaft 2 is, in other words,
At the tip, it is detachably formed at the rotation center of the rotating body 5.

On the opposite side of the pump chamber 1 in the magnet housing chamber 3, there is a function of generating a rotating magnetic field rotating around the axis of the rotating shaft 2. A magnetic field generator (not shown) is provided. The stationary rotating magnetic field generator includes an iron core having six arms extending radially around the axis of the rotating shaft 2. A coil is wound around each of the six arms of the iron core. The coil is connected to a three-phase inverter. By energizing the coil with the alternating current from the three-phase inverter, a rotating magnetic field that rotates around the axis of the rotating shaft 2 is generated.

When the blood pump of Example 1 is used, the protrusion on the periphery of the flange portion C41 of the rotating body housing case C4 is engaged with the groove in the casing body B1, and the magnet housing chamber 3 is mounted on the bottom of the pump chamber 1. Join. At this time, the plug portion 21 of the rotary shaft 2 is inserted into the drive shaft 4 inside the socket portion 41 of the joint 40, and the rotary shaft 2 and the drive shaft 4 are connected as shown in FIG. Is done.

When a three-phase alternating current of a specific frequency and voltage is applied from the three-phase inverter to the coil of the stationary rotating magnetic field generator, a rotating magnetic field is generated in the coil, and the rotating body 5 in the magnet housing chamber 3 is provided. The permanent magnet C3 rotates by being attracted by the rotating magnetic field, whereby the rotating body 5 and the drive shaft 4 also rotate. Here, as described above, the drive shaft 4
Is coupled to the rotary shaft 2 by the joint 40, the drive shaft 4 and the rotary shaft 2 rotate integrally, and therefore, the impeller A fixed to one end of the rotary shaft 2 also Rotate. Thus, blood is sucked and discharged in the pump chamber 1.

FIG. 3 shows a state in which the pump chamber 1 is separated from the magnet housing chamber 3 in the blood pump of Example 1. When the blood pump of Example 1 is discarded, the engagement between the protrusion on the peripheral portion of the flange portion C41 of the rotating body housing case C4 and the groove in the casing body B1 is released, and the magnet housing chamber 3 is moved to the pump chamber 1. Pull away from. Thereby, as shown in FIG. 2A, the plug part 21 is detached from the socket part 41 of the joint 40, and the rotary shaft 2 and the drive shaft 4 are separated. Thereby, the pump chamber 1 is separated from the magnet housing chamber 3 as shown in FIG.

After the pump chamber 1 is separated from the magnet housing chamber 3, only the pump chamber 1 that has come into contact with the patient's blood may be discarded, and the magnet housing chamber 3 having a large number of non-combustible members such as permanent magnets C3 is provided. , Is reusable. If the rotary shaft 2 and the plug portion 21 are made of a flammable material such as a synthetic resin in the pump chamber 1, almost no portion remains as a non-flammable portion when the pump chamber 1 after disposal is incinerated. It is therefore particularly preferred because the generation of residual ash can be greatly reduced.

FIG. 4 shows another example of a joint for detachably connecting the rotary shaft and the drive shaft in the blood pump of the present invention. In FIG. 4, the same reference numerals as those in FIGS. 1 and 2 indicate the same elements and members as those indicated in FIGS. 1 and 2, unless otherwise specified.

FIG. 4A is a partial sectional view showing an example of a so-called lock pin type joint. The coupling 40 shown in FIG. 4A includes a pair of lock pins 25a and 25b, which are pin-shaped members protruding from the outer peripheral portion of the end surface of the rotating shaft 2 that is coupled to the drive shaft 4, and a drive shaft. And a pair of lock pin receiving holes 47a, which are formed in a direction perpendicular to the end surface on the end surface of the end surface on the side coupled to the rotating shaft 2 and are bottomed holes for receiving the lock pins 25a and 25b, 47b.

The lock pin 25b is located on the opposite side of the lock pin 25a with respect to the axis of the rotating shaft 2. Projections protruding outward are formed at the tips of the lock pins 25a and 25b, respectively. on the other hand,
The lock pin receiving hole 47b is located on the opposite side of the lock pin 47a with respect to the axis of the drive shaft 4. Enlarged portions corresponding to the protrusions formed at the tips of the lock pins 25a and 25b are formed at the bottoms of the lock pins 47a and 47b, respectively.

In the joint 40 shown in FIG. 4A, the lock pins 46a and 46b are
The rotary shaft 2 and the drive shaft 4 can be connected by inserting and fitting into the receiving hole 47a and the lock pin receiving hole 47b, respectively.

When separating the rotating shaft 2 and the driving shaft 4 which are connected to each other, a force is applied in a direction to separate the rotating shaft 2 and the driving shaft 4 from each other. As a result, the lock pins 46a and 46b are
7a and 47b, the rotating shaft 2 and the drive shaft 4 are separated from each other.

FIG. 4B is a schematic view showing an example of a so-called grooved lap joint. The joint 40 shown in FIG. 4B has a groove 26 formed in a direction perpendicular to the axis of the rotating shaft 2 near the end face of the rotating shaft 2 to which the drive shaft 4 is coupled, and In the vicinity of the end face of the drive shaft 4 on the side where the rotary shaft 2 is coupled, a groove 48 is formed in a direction perpendicular to the axis of the drive shaft 4.
And, between the groove 26 and the end face of the rotary shaft 2, a fitting portion 26 a fitted in the groove 48 of the drive shaft 4.
Are formed. Similarly, between the groove 48 and the end face of the drive shaft 4, a fitting portion 48 a to be fitted in the groove 26 of the rotating shaft 2 is formed.

The fitting portion 48 of the drive shaft 4 is inserted into the groove 26 of the rotary shaft 2.
a, and the fitting portion 26 of the rotary shaft 2 is fitted into the groove 48 of the drive shaft 4.
By fitting a, the rotating shaft 2 and the driving shaft 4 are connected.

FIG. 4C is a partial sectional view showing an example of a joint 40 having a so-called screw type joint. The joint 40 includes a screw portion 27 formed at the end of the rotary shaft 2 on the side where the drive shaft 4 is coupled, and a screw hole 49 formed on the end of the drive shaft 4 on the side where the rotary shaft 2 is coupled. Is provided.

The rotary shaft 2 and the drive shaft 4 are connected to the screw holes 49.
By screwing the screw portion 27 to the upper portion.

2. Supplementary explanation As the rotating magnet device of the present invention, in addition to the stationary rotating magnetic field generating device described in the blood pump of the first embodiment, a rotating magnetic pole type rotating magnetic field generating device having a rotating magnetic pole rotated by a rotating means such as a motor. And the like.

[0052]

According to the present invention, at the time of disposal, the magnet chamber for accommodating the magnet for rotating the impeller is separated from the pump chamber, and the magnet chamber is reused to reduce the amount of waste. A disposable blood pump capable of reducing the blood pressure is provided.

Among the blood pumps provided by the present invention, those whose rotary shaft is formed of a flammable material such as synthetic resin are used when the pump chamber is separated from the magnet chamber and the pump chamber is incinerated. In addition, it has a feature that almost no residual ash is produced.

[0054] Among the blood pumps provided by the present invention, the blood pump having the inner seal member and the outer seal member has the above-mentioned features, and in addition to the above-mentioned features, the pump chamber 1 when the pressure inside the pump chamber 1 abnormally rises. In addition to effectively preventing the leakage of blood from the inside and the intrusion of air into the pump chamber 1 when the pressure is abnormally reduced, when the pressure inside and outside the pump chamber is balanced, the rotation shaft It has the feature that rotation is extremely smooth.

[Brief description of the drawings]

FIG. 1 is an example 1 which is an example of the blood pump of the present invention.
FIG. 2 is a cross-sectional view showing the structure of the blood pump of FIG.

FIG. 2 is a partial cross-sectional view showing a structure of a joint in the blood pump of Example 1.

FIG. 3 is a sectional view showing a state where a pump chamber and a magnet housing chamber are separated in the blood pump of Example 1.

FIG. 4 is a partial cross-sectional view showing another example of the joint in the blood pump of Example 1.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pump chamber; 2 ... Rotary shaft, 21 ... Plug part, 22 ...
Spherical concave portion, 23 ... reduced portion, 24 ... groove, 25a, 25
b ... lock pin, 26 ... groove, 26a ... fitting part, 27 ... screw part; 3 ... magnet accommodation chamber; 4 ... drive shaft, 41 ...
Socket part, 42 spherical projection, 43 first O-ring fitting groove, 44 cylindrical member, 45, 46 O-ring, 4
7a, 47b: lock pin receiving hole, 48: groove, 48
a: fitting portion, 49: screw hole; 5: rotating body; A: impeller, A1: rotary table, A2: blade, A3: liquid flow through hole;
B: Casing, B1: Casing body, B11: Blood suction tube, B12: Blood discharge tube, B2: Casing cover, B21: Rotating shaft insertion hole, B22: Enlarged portion, B3: Bearing, B4: Packing; C1: Rotor portion , C2: hub portion, C3: permanent magnet, C4: rotating body housing case, C41
... Flange-shaped part, C42 ... O-ring, C5 ... Bearing;
D1 ... Seal member, D2, D3 ... V ring.

Claims (3)

[Claims] 1. A pump chamber for discharging introduced blood by rotating an impeller having a rotating shaft, and a magnet which is detachably formed in the pump chamber and which can be rotated by a rotary magnet device. A blood pump, comprising: a magnet housing chamber containing a mounted rotating body. 2. The rotary shaft is inserted into a rotary shaft insertion hole formed in a bottom surface, which is a wall surface of the pump chamber facing the magnet housing chamber, and a tip of the rotary shaft is detachably attached to a rotation center of the rotary body. The blood pump according to claim 1, wherein the blood pump is formed. 3. The pump chamber according to claim 1,
The internal seal member mounted on the rotary shaft according to claim 1, which expands toward the rotary shaft insertion hole according to claim 2, and expands toward the rotary shaft insertion hole outside the pump chamber. However,
The blood pump according to claim 2, further comprising an external seal member mounted on the rotation shaft.