JPH046762Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the structure of a blood pump used for extracorporeal circulation of blood in artificial blood dialysis and the like.

[Conventional technology]

In artificial blood dialysis, blood is once taken out of the human body, and after harmful substances, excess water, etc. are removed by diafiltration in an artificial dialysis machine, the blood is returned to the human body. A blood pump is installed in this extracorporeal blood circulation system, but the blood pump usually delivers a small flow of blood with precision and avoids contact between the patient's blood through the blood contact part of the pump. Therefore, a so-called tube pump using a disposable tube is used.

A blood pump consisting of a conventional tube pump is
For example, it is configured as shown in FIG. In the figure, 1 is a casing having a cylindrical inner circumferential surface 2, and a tube 3 is disposed along the inner circumferential surface 2 of the casing 1. The tube 3 is locally pressed in the direction of the inner circumferential surface of the casing by rollers 5 attached to both ends of the rotor 4, so that the tube 3 is locally pressed and closed by rollers 5 attached to both ends of the rotor 4. By rotating it with a motor), the closing point is moved along the inner circumferential surface 2, thereby making it possible to send blood in the direction of the arrow in the figure.

In such a blood pump 6, due to its structure, the blood suction side 3a and the blood discharge side 3b of the tube 3 are pulled out in the same direction with respect to the casing 1. Further, in order to prevent the expansion and accumulation of air bubbles in the blood, the suction side 3a is always arranged on the lower side and the discharge side 3b is arranged on the upper side. Since many patients use their left arm for puncturing for extracorporeal circulation of blood, the direction in which the tube 3 of the blood pump 6 is drawn out is usually fixedly set to the patient's left side. By doing so, for a patient whose blood is extracorporeally circulated from the left arm, the extracorporeal blood circuit can be made as short as possible, and the blood volume in the circuit can be kept small.

[Problem that the invention attempts to solve]

However, in patients who have been receiving treatment that involves extracorporeal circulation of blood over a long period of time, as is often the case with artificial dialysis patients, the skin and blood vessels near the puncture site become hardened or damaged as the total number of punctures increases. , it may become impossible to collect blood from nearby areas. In such cases, it may be possible to change the puncture position from the left arm to the right arm, but if the puncture position is changed to the right arm while maintaining the relative positional relationship between the existing blood pump and the patient, the blood circuit tube may move back and forth over the patient's body. This results in undesirable problems such as the blood circuit becomes longer and the blood volume within the circuit increases, and restrictions on the patient's posture and movement become stronger. In addition, if you place the blood pump on the right side of the patient in order to shorten the blood circuit length, you can place the blood pump 6 face down or inverted if you want the drawer side of the tube to face the patient. Must. Normally, the blood pump 6 is incorporated into a set of equipment including an artificial dialysis machine, so if it is installed face down, the operation side of the equipment will be face down, which may cause problems. becomes inoperable. If it is installed upside down, the above-mentioned vertical relationship between the blood suction side 3a and the discharge side 3b cannot be maintained.

The present invention focused on the above-mentioned problems, and while ensuring a predetermined vertical relationship between the suction side and the discharge side of the tube, nurses and others can easily change the direction in which the tube is drawn out from the blood pump according to the patient's situation. The structure of the blood pump can be changed easily, and the relative positional relationship between the patient and the blood pump can be easily changed from side to side without changing the direction of the operation surface, and the blood volume in the extracorporeal blood circuit can be adjusted. The purpose is to always keep the capacity to the minimum necessary.

[Means for solving problems]

The tube draw-out direction variable blood pump of the present invention, which meets this purpose, has a flexible tube through which blood can flow, and is arranged around the inner circumference of a casing having an arcuate (preferably semi-cylindrical) inner circumferential surface. disposed in the circumferential direction of the inner circumferential surface along the surface, pulling both sides of the tube outside the casing, and providing a roller capable of locally pressing the tube toward the inner circumferential surface of the casing; A blood pump incorporated in an extracorporeal blood circulation circuit that transports blood in a tube by moving the position of the roller in the circumferential direction of the inner circumferential surface of the casing by a rotational drive source. , a casing reversing mechanism for reversing the tube pull-out direction of the casing by rotating the casing around the rotation axis of the rotary drive source; a reversal detection mechanism for detecting reversal of the casing; and a reversal detection mechanism for detecting reversal of the casing; A control circuit is provided for switching the direction of rotation of the rotary drive source in accordance with a signal.

As the rotational drive source, a reversible motor, such as a DC motor, is used, and the roller is rotated in the circumferential direction of the inner peripheral surface of the casing via, for example, a rotor connected to a shaft of the reversible motor.

[Effect]

In such a blood pump, when changing from, for example, setting to draw blood from the patient's left arm to drawing blood from the right arm, the reversing mechanism changes the orientation of the casing by 180 degrees.
The tube drawing direction is changed by 180 degrees. At this time, the suction side tube that was located on the lower side before the reversal will be on the upper side after the reversal, and the discharge side tube that was located on the upper side before the reversal will be on the lower side after the reversal. However, since the reversal of the casing is detected by the reversal detection mechanism and the rotational direction of the rotational drive source is switched according to the detection signal, the rotational direction of the roller along the cylindrical inner peripheral surface of the casing is different from that before the reversal. will be reversed after the casing is reversed,
Even after reversal, the drawer tube located on the lower side becomes the suction side, and the drawer tube located on the upper side becomes the discharge side, ensuring a predetermined vertical relationship. This switching is performed by the reversal detection mechanism, as the casing is reversed.
Since this is done automatically via a control circuit, it is performed reliably without any human error. Since the casing is simply rotated 180 degrees while leaving the predetermined operating surface direction of the blood pump unchanged, the operating surface direction of the entire device such as an artificial dialysis machine in which the blood pump is incorporated remains unchanged. , while maintaining the direction of the operation surface in a predetermined direction.
The relative positions of the patient and blood pump are reversed. This reversal allows the extracorporeal blood circuit to always have the minimum necessary capacity depending on the patient's situation.

〔Example〕

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

1 to 4 show a blood pump with variable tube drawing direction according to an embodiment of the present invention, and FIG. 2 shows a case where the blood pump is applied to artificial dialysis of blood. In the figure, 11 indicates the entire blood pump, and blood pump 11
is incorporated into the extracorporeal blood circulation circuit as shown in FIG. Blood collected from a human body, for example, an arm 12, is sucked by the blood pump 11 and is pumped from the blood pump 11 to the chamber 1.
3 and then sent to the artificial dialyzer 14. In the artificial dialyzer 14, the dialysate supply line 15
Diafiltration is performed between the blood and the blood to remove harmful substances and excess water. The blood after dialysis is once stored in the chamber 16 and then returned to the human body.

Blood pump 11 is constructed as shown in FIGS. 1 and 3. 21 is a casing having a semi-cylindrical inner peripheral surface 22;
1 is fixed to a panel 23 of the entire device.

On the inner circumferential surface 22 of the casing 21, there is a flexible tube that extends along the inner circumferential surface 22 in the circumferential direction of the inner circumferential surface 22 and then extends outside the casing 21, allowing blood to flow therethrough. A tube 24 is provided. A rotor 27 connected to a shaft 26 of a motor 25 as a rotational drive source is provided within the curved portion of the tube 24, and rollers 28 are rotatably attached to both ends of the rotor 27. The roller 28 is arranged at a position where it can press the tube 24 in the direction of the inner peripheral surface of the casing until the tube 24 is locally compressed, and as the rotor 27 rotates, it moves the tube compression point in the direction of the arrow. It is now possible to move to In FIG. 1, the vertical direction is shown to match the vertical direction when the blood pump 11 is actually attached to a dialysis machine or the like. Therefore, the lower drawer tube 24a in the figure is the blood suction side, and the upper tube 24b is the blood suction side.
is on the discharge side.

Due to the movement of the rotor 28 as the rotor 27 rotates, the closing point of the tube 24 moves in the circumferential direction of the casing inner circumferential surface 22, whereby the blood sucked from the suction side tube 24a is transferred to the discharge side tube 24b. sent from. In this roller pump type blood pump, the roller 28 returns from the discharge side to the suction side, but when returning to the suction side, the pressure and closing of the tube 24 by the roller 28 is temporarily released, so that the roller 28 If only one tube is provided, tube 2 will be closed while the pressure is released.
This means that the flow of blood within 4 cannot be regulated. Therefore, at least two rollers 28 are provided so that the tube 24 always has one or more closing points, and in this embodiment, by providing the rollers 28 at 180 degrees opposite positions, one roller 28 Immediately before the pressure-closing is released on the discharge side, the other roller 28 starts compressing and closing on the suction side.

The casing 21 is fixed to the panel 23 via pins 29. If you remove pin 29,
The casing 21 is rotatable around the shaft 26 of the motor 25, and can be easily rotated as shown in FIG.
It can be flipped 180 degrees. If the pin 29 is inserted after turning over, the casing 21 is fixed to the panel 23 again. Therefore, the above mechanism constitutes a casing reversing mechanism that reverses the drawing direction of the tube 24 of the casing 21 by reversing the casing 21.

A striker 3 is mounted on the outer peripheral shoulder of the casing 21.
A limit switch 31 is provided at a position opposite to the striker 30 when the casing 21 is in the attitude shown in FIG.
The lever 31a of the limit switch 31 comes into contact with the striker 30 in the state shown in FIG. 1, and generates a detection signal. When the casing 21 is reversed as shown in FIG. 4, the striker 30 and the lever 31a are disengaged, and a signal to disengage the engagement is also emitted from the limit switch 31. Therefore, the limit switch 31 and the striker 30 are connected to the casing 21.
It constitutes a reversal detection mechanism that detects whether or not the is reversed.

Note that the detector may be of any type other than the above-mentioned limit switch; for example, a well-known detector such as a proximity switch may be used. Also, regarding the detection mechanism, there is no need to intentionally provide the striker 30, but simply make a suitable part of the casing 21 into a notch shape, etc., and engage and disengage with the detector according to the reversal of the casing. You can do it like this.

A limit switch 31 serving as a detector is connected to a control circuit 32, and a reversal detection signal of the casing 21 is sent to the control circuit 32. In response to this signal, the control circuit 32 sends the motor drive circuit 3 to the motor drive circuit 3.
3, a predetermined motor rotation direction command signal is sent. That is, when the casing 21 is in the posture shown in FIG. 1, the motor 25 is rotated in the direction of the arrow in FIG. ,
That is, it is rotated in the direction of the arrow in FIG. If the motor 25 is a DC motor, this switching of the rotation direction can be easily performed by switching the polarity.

In the blood pump 11 configured as described above, if the arrangement shown in FIG. If the direction is towards the left arm of the patient, the drawer tube 24a has a short length and can reach the puncture position of the patient's left arm for a patient whose blood is normally collected from the left arm.
The length of the blood return tube after dialysis is also shortened, and the capacity of the extracorporeal blood circulation path is also minimized.

To perform artificial dialysis on a patient whose blood is to be collected from the right arm while maintaining the equipment arrangement shown in Figure 2,
Move the set of equipment to the right side of the patient and
In order to draw out the tube 24 from the blood pump 11 toward the patient's right arm, it is necessary to turn the operation surface of the entire device face down. However, in the present invention, while maintaining the direction of the operation surface in a predetermined direction,
The drawing direction of the tube 24 of the blood pump 11 is changed to the patient's right arm side. In other words, the pin 29 is pulled out and the casing 21 is moved 180 degrees from the state shown in FIG.
It is rotated once to the inverted state shown in FIG. 4, and the pin 29 is inserted again to fix it to the panel 23. At this time, the reversal of the casing 21 is detected by the limit switch 31, and the signal is sent to the control circuit 3.
2, and the rotational direction of the motor 25 is simultaneously and automatically reversed via the motor drive circuit 33. By reversing the rotational direction of the motor 25, even after the casing 21 is reversed, the necessary condition that the lower drawer tube is on the suction side and the upper drawer tube is on the discharge side is satisfied. Therefore, this hierarchical relationship is
It will always be filled whether the tube 24 is pulled out in the direction shown in FIG. 1 or in the direction shown in FIG.

When the casing 21 is inverted as shown in FIG. 4, the tube is pulled out in the direction of the patient's right arm, so that the minimum required capacity of the extracorporeal blood circulation path is achieved in this case as well.

Although the above embodiments have been described for the case of artificial dialysis of blood, the present invention is not limited to this, and the blood pump of the present invention can be applied to all cases where the blood pump is installed in an extracorporeal blood circulation path.

[Effect of idea]

As explained above, when using the variable tube draw-out direction blood pump of the present invention, the casing can be reversed, and in conjunction with the reversal, the rotational direction of the rotary drive source is simultaneously and automatically reversed. Therefore, it is possible to easily set up a blood circuit for extracorporeal circulation on either the left or right side of the patient depending on the patient's situation, while maintaining the operating surface of devices such as artificial dialysis in a predetermined direction. The effect is that the capacity of the blood circuit can be suppressed to the necessary minimum.

In addition, the blood pump of the present invention allows even people who are not experts in equipment to easily change the direction in which the tube is pulled out at treatment sites such as hospitals, and the rotational direction of the roller automatically changes in accordance with the direction in which the tube is pulled out. Therefore, it is possible to reliably prevent human errors in the rotation direction.

[Brief explanation of the drawing]

Fig. 1 is a front view of a blood pump according to an embodiment of the present invention, Fig. 2 is an extracorporeal blood circulation circuit diagram incorporating the blood pump of Fig. 1, and Fig. 3 is along the - line in Fig. 1. A sectional view, FIG. 4 is a front view of the blood pump shown in FIG. 1 when the casing is inverted, and FIG. 5 is a front view of the conventional blood pump. 11... Blood pump, 14... Artificial dialysis machine, 2
DESCRIPTION OF SYMBOLS 1... Casing, 22... Inner peripheral surface, 23... Panel, 24... Tube, 24a, 24b... Drawer tube, 25... Motor as rotational drive source, 26... Motor shaft, 27... Rotor, 28
...Roller, 29 ... Pin, 30 ... Striker, 31 ... Limit switch, 31a ... Lever, 32 ... Control circuit, 33 ... Motor drive circuit.

Claims (1)

[Scope of utility model registration request] A flexible tube through which blood can flow is disposed along the inner circumferential surface of a casing having an arc-shaped inner circumferential surface in the circumferential direction of the inner circumferential surface, and both sides of the tube are Pull the drawer out of the casing,
A roller capable of locally pressing the tube in the direction of the inner circumferential surface of the casing is provided, and the position of the roller is moved in the circumferential direction of the inner circumferential surface of the casing by a rotational drive source, thereby removing the blood in the tube. A blood pump incorporated into an extracorporeal circulation circuit for blood, which pumps liquid, wherein the blood pump has a casing in which the direction of tube withdrawal of the casing is reversed by rotating the casing around a rotation axis of the rotational drive source. A blood tube with variable drawing direction, comprising: a reversal mechanism; a reversal detection mechanism that detects reversal of the casing; and a control circuit that switches the rotational direction of the rotational drive source in accordance with a signal from the reversal detection mechanism. pump.