JP2011056013A - Hemodialyzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make a sealing member 3 anchored to the inner surface of a casing 2 durable against the pressure from an O-ring 4, and to prevent bubbles from being accumulated within the sealing member 3 in discharging bubbles included in the sealing member. <P>SOLUTION: An inclined surface 14 on the inner surface of the casing 2 supports the sealing member 3. When bubbles are discharged from the sealing member 3, the bubbles are moved along the inclined surface 14 to be discharged from the sealing member 3, so that accumulation of bubbles within the sealing member 3 can be prevented. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a hemodialyzer comprising a casing that accommodates a bundle of hollow fiber membranes, and further having a sealing member that fixes the hollow fiber membrane bundle and is sealed to the inner peripheral surface of the casing.

  It is called a dialyzer as an instrument for performing hemodialysis that discharges waste products and excess water in the blood through the dialysis membrane into the dialysate and sends the electrolyte in the dialysate through the dialysis membrane into the blood. Hemodialyzers are known.

  The dialyzer is laminated with sheet-shaped dialysis membranes, and blood is flowed into the hollow fiber membrane, which is a straw-type dialysis membrane. A hollow fiber type in which dialysate is allowed to flow outside is known. Among these, the hollow fiber type dialyzer is known to have higher dialysis efficiency than the laminated type, and has been rapidly spread in recent years.

  The hollow fiber type dialyzer accommodates a bundle of hollow fiber membranes, has a cylindrical casing provided with a dialysate supply port and a discharge port, and is fixed to both ends of the casing, and is provided with a blood flow port. And a liquid passing cap.

  Further, a sealing member called a potting material is provided in the casing, which fixes the end of the hollow fiber membrane bundle in the casing and seals the casing so that the dialysate does not leak from the casing. Yes. This sealing member is made of a thermosetting resin such as polyurethane, phenol resin, epoxy resin, etc., and fills the gap between the end portions of the hollow fiber membrane, and is closer to the end side than the dialysate supply port and the discharge port of the casing. It is fixed to the inner peripheral surface of the casing.

  Further, in order to prevent blood from leaking through the gap between the end of the casing and the liquid passing cap, an O-ring is sandwiched between the sealing member and the liquid passing cap. At this time, when the O-ring is sandwiched between the sealing member and the liquid passing cap in a pressurized state, the sealing member is pressed against the O-ring, and as a result, the sealing member is peeled off from the inner peripheral surface of the casing. There is a risk that. Therefore, as shown in FIG. 1, in the conventional hemodialyzer 1, the sealing member 3 fixed to the inner peripheral surface of the casing 2 is sealed on the inner peripheral surface of the casing so that it can withstand the pressure of the O-ring 4. A step 5 is provided on the surface to which the stop member 3 is fixed.

JP 2001-70759 A

By the way, the sealing member 3 is fixed to the inner peripheral surface on the end side of the casing 2 through the following steps.
(1) After accommodating the hollow fiber membrane bundle 6 in the casing, sealing caps (not shown) are fixed to both ends of the casing 2, and both ends of the casing 2 are sealed.
(2) The liquid sealing member 3 is injected into the casing 2 from the dialysate supply port 7 and the discharge port 8 of the casing 2.
(3) The sealing member 3 is brought close to the end of the casing 2 by rotating the casing 2 around a rotation axis that is located at the center of the casing 2 in the axial direction and is perpendicular to the axial direction. Further, if the casing 2 continues to rotate even after the sealing member 3 approaches the end of the casing 2, bubbles contained in the sealing member 3 are pushed out toward the center of rotation from the principle of centrifugal separation. As a result, bubbles are removed from the sealing member 3.
(4) The sealing member 3 is heated and cured.

  Here, if bubbles remain in the sealing member 3 without being removed from the sealing member 3 in the step (3), the bubbles expand and are cured when the sealing member 3 is heated in the step (4). There is a risk of cracks in the sealing member. On the other hand, if the step 5 is provided on the inner peripheral surface of the casing, bubbles may be caught in the step 5 and remain in the sealing member 3 as it is.

  Therefore, an object of the present invention is to provide a hemodialyzer that can withstand the pressure from an O-ring and prevent air bubbles from staying in the sealing member.

  The invention according to claim 1 has a cylindrical shape with an open end, a casing having a dialysate supply port and a dialysate discharge port, and a flow passage fixed to both ends of the casing and provided with a blood flow port. The end portion of the hollow fiber membrane bundle is fixed by filling the liquid cap, the hollow fiber membrane bundle accommodated in the casing, and the gap between the end portions of the hollow fiber membrane, and the dialysate supply port and dialysate of the casing A hemodialyzer comprising: a sealing member fixed to the inner peripheral surface of the casing on the end side of the discharge port; and an O-ring sandwiched between the liquid passing cap and the sealing member. Of the inner peripheral surface of the casing, the surface to which the sealing member is fixed is provided with an enlarged diameter portion having an inner diameter on the end portion side of the casing larger than that of the central portion side. An inclined surface connected to the inner peripheral surface of the casing is formed, and blood It is a crystallizer.

  The invention according to claim 2 is the hemodialyzer according to claim 1, wherein the enlarged diameter portion is provided over the entire circumference of the casing inner peripheral surface, and the inner peripheral surface of the casing end portion includes the inside of the casing. An inclined surface is provided connected to a surface extending from the opening of the dialysate supply port and the dialysate discharge port provided on the peripheral surface to the casing end along the axial direction of the casing, and is provided on the inner peripheral surface of the casing end. Among them, a step is provided by connecting to a surface other than the surface extending from the opening of the dialysate supply port and the dialysate discharge port provided on the casing inner peripheral surface to the casing end side along the axial direction of the casing, It is characterized by that.

  The invention according to claim 3 is the hemodialyzer according to claim 2, characterized in that a chamfered portion is provided in a portion of the step which is in contact with the inclined surface.

  According to the invention which concerns on Claim 1, since the inclined surface of a diameter-expanded part supports a sealing member, the sealing member can endure the press of an O-ring. Further, since the bubbles are pushed out toward the rotation center along the inclined surface, the bubbles can be prevented from staying in the sealing member.

It is a figure which shows the hemodialyzer 1 which concerns on this embodiment. It is a figure which shows the hemodialyzer 1 which concerns on another embodiment. It is an enlarged view of the internal peripheral surface by the side of a casing edge part. It is an enlarged view of the internal peripheral surface by the side of a casing edge part. It is a figure explaining the process of assembling the hemodialyzer. It is a figure explaining the process of assembling the hemodialyzer. It is a figure explaining the process of assembling the hemodialyzer. It is a figure explaining the motion of the bubble in the sealing member. It is a figure explaining the process of assembling the hemodialyzer. It is a figure which shows the hemodialyzer 1 which concerns on a prior art.

  First, the configuration of the hemodialyzer according to this embodiment will be described. FIG. 1 shows a cross-sectional view of a hemodialyzer 1 according to this embodiment.

  The hemodialyzer 1 is provided with a cylindrical casing 2 and liquid passing caps 9 and 10 fixed to both ends of the casing 2. The blood flow caps 9 and 10 are provided with blood flow ports 11 and 12, and a tube (not shown) is connected between the blood flow ports 11 and 12 and the patient.

  The casing 2 is provided with a dialysate supply port 7 and a dialysate discharge port 8. Further, a hollow fiber membrane bundle 6 is accommodated in the casing 2, and a sealing member 3 that fixes the hollow fiber membrane bundle 6 and seals the casing 2 is fixed to the inner peripheral surface of the casing 2.

  Further, an O-ring 4 made of an elastic body is sandwiched between the liquid passing caps 9 and 10 and the sealing member 3.

  In addition, on the surface of the inner peripheral surface of the casing 2 to which the sealing member 3 is fixed, a diameter-expanded portion 13 having an inner diameter on the end portion side of the casing larger than that on the central portion side is provided. Further, an inclined surface 14 connected to the inner peripheral surface of the casing 2 is formed on the bottom surface of the enlarged diameter portion 13.

  In FIG. 1, the bottom surface of the enlarged diameter portion 13 is composed of a surface perpendicular to the axial direction of the casing and the inclined surface 14, but may be composed of only the inclined surface 14 as shown in FIG. 2. . Further, the enlarged diameter portion 13 and the inclined surface 14 in FIGS. 1 and 2 may be provided over the entire circumference of the inner peripheral surface of the casing 2 or may be provided in a part of the inner peripheral surface of the casing.

  The configuration of the hemodialyzer 1 according to the present embodiment has been described above. Next, operations of the dialysate supply port 7, the dialysate discharge port 8, the sealing member 3, the O-ring 4, and the inclined surface 14 will be described.

  The dialysate supply port 7 supplies dialysate into the casing 2, and the dialysate discharge port 8 discharges dialysate that has received waste and excess water from the blood from the casing 2. Further, as will be described later, the dialysate supply port 7 and the dialysate discharge port 8 also serve as injection ports for injecting the liquid sealing member 3 into the casing 2.

  The sealing member 3 is also called a potting material and is made of a thermosetting resin such as polyurethane, phenol resin, or epoxy resin. The sealing member 3 fixes the hollow fiber membrane bundle 6 by filling the gaps of the hollow fiber membranes, and the inner periphery of the casing 2 on the end side of the dialysate supply port 7 and dialysate discharge port 8 of the casing 2. It is fixed to the surface. Since the casing 2 is sealed by filling the gap between the hollow fiber membranes with the sealing member 3 and being fixed to the inner peripheral surface of the casing 2, leakage of the dialysate can be prevented. Further, the end opening of the hollow fiber membrane bundle 6 is exposed on the surface of the sealing member 3 facing the liquid passing caps 9 and 10, and the blood flowing from the liquid passing caps 9 and 10 is exposed to this end portion. Enter the hollow fiber membrane from the opening.

  The O-ring 4 is sandwiched in a pressurized state between the liquid passing caps 9 and 10 and the sealing member 3, whereby blood leaks from the gap between the liquid passing caps 9 and 10 and the casing 2. It prevents that.

  Further, the inclined surface 14 supports the sealing member 3 pressed against the O-ring 4. When the O-ring 4 is sandwiched between the liquid-permeable caps 9 and 10 and the sealing member 3 in a pressurized state, the O-ring 4 presses the sealing member 3. At this time, the inclined surface 14 supports the sealing member 3 pressed by the O-ring 4. As a result, the sealing member 3 can withstand the pressure from the O-ring 4, and as a result, the sealing member 3 can be prevented from peeling off from the inner peripheral surface of the casing 2.

  Furthermore, the inclined surface 14 has a structure that does not hinder the movement of the bubbles when the bubbles contained in the sealing member 3 are pulled out of the sealing member 3. As will be described later, in the process of fixing the sealing member 3 to the inner peripheral surface of the casing 2, the liquid sealing member 3 is injected into the casing 2 whose both ends are sealed, and then the axial center of the casing 2 is injected. The air bubbles contained in the sealing member 3 are driven to the rotation center side by rotating the casing 2 around the rotation axis perpendicular to the axial direction. Here, the bubbles in the enlarged diameter portion 13 move in the direction of the rotation center along the inclined surface 14, and then come out of the sealing member 3. In this way, since the bubbles get over the inclined surface 14 and come out of the sealing member 3, the bubbles can be prevented from staying in the sealing member 3.

  Here, when the enlarged diameter portion 13 is provided on the entire inner peripheral surface of the casing, the inclined surface 14 is connected to the portion of the inner peripheral surface of the casing 2 where particularly bubbles are generated, and the remaining portion is inclined. A step 5 may be provided instead of the surface 14. Specifically, among the inner peripheral surface on the end portion side of the casing 2, along the axial direction of the casing 2 from the openings of the dialysate supply port 7 and the dialysate discharge port 8 provided on the inner peripheral surface of the casing 2. It has been empirically found that bubbles are concentrated on the surface extending to the end of the casing 2. Therefore, the inclined surface 14 may be connected to the surface, and the step 5 may be connected to the other inner peripheral surface on the end side of the casing 2. With this configuration, the sealing member 3 can be supported over the entire circumference, and bubbles can be prevented from staying in the sealing member 3.

  When the above-described configuration is provided, a part of the step 5 may protrude as shown by the protrusion 15 at the boundary between the inclined surface 14 and the step 5 as shown in FIG. 3A. Then, when the inclined surface 14 and the step 5 support the sealing member 3, stress against the pressure from the sealing member 3 is concentrated on the protruding portion 15, which may lead to cracking of the sealing member 3. Therefore, as shown in FIG. 3B, a chamfered portion 16 may be formed by removing the protruding portion 15 in the portion of the step 5 in contact with the inclined surface 14.

  The configuration and operation of the hemodialyzer 1 according to this embodiment have been described above. Next, the process of assembling the hemodialyzer 1 will be described.

  <Step 1> As shown in FIG. 4, the hollow fiber membrane bundle 6 is accommodated in the casing 2. Since the hollow fiber membrane bundle 6 is cut off at both ends in step 5 to be described later, the hollow fiber membrane bundle 6 is slightly longer than the axial length of the casing 2 in preparation for this. It protrudes slightly from both ends.

  <Step 2> As shown in FIG. 5, sealing caps 17 and 18 are fixed to both ends of the casing 2 to seal both ends of the casing 2. Thereafter, the liquid sealing member 3 is injected into the casing 2 from the dialysate supply port 7 and the dialysate discharge port 8.

  <Step 3> As shown in FIG. 6, the casing 2 is rotated around a rotation shaft 19 which is located at the center of the casing 2 in the axial direction and is perpendicular to the shaft. By this rotation, the liquid sealing member 3 is brought close to the end side of the casing 2. At this time, the gap between the hollow fiber membranes is filled with the sealing member 3. Further, when the casing 2 is continuously rotated even after the sealing member 3 is brought close to the end of the casing 2, the bubbles in the sealing member 3 are pushed out toward the rotation center side by the principle of centrifugal separation. Thereby, bubbles in the sealing member 3 are extracted.

  The process of removing the bubbles will be described with reference to FIG. The bubble 20 in the sealing member 3 moves toward the center of rotation. Here, the bubble 20 in the enlarged diameter portion 13 moves in the direction of the rotation center along the inclined surface 14 in the process of moving in the direction of the rotation center, and then comes out of the sealing member 3. As described above, since the bubbles 20 get over the inclined surface 14 and come out of the sealing member 3, the bubbles 20 can be prevented from staying in the sealing member 3.

  <Step 4> The sealing member 3 is heated to cure the sealing member 3, and the sealing member 3 is fixed to the inner peripheral surface of the casing 2. At this time, if the bubbles 20 remain in the sealing member 3, the bubbles 20 are expanded by heating, and the sealing member 3 being cured may be cracked. As described above, in the present embodiment, Since the bubbles 20 in the sealing member 3 are removed from the sealing member 3 without staying, there is no possibility that the sealing member 3 is cracked.

  <Step 5> As shown in FIG. 8, the sealing caps 17 and 18 are removed from the casing 2, and the hollow fiber membrane bundle 6 protruding from the casing 2 and the surrounding sealing member 3 are cut out. When the liquid sealing member 3 is brought close to the end of the casing 2 in the above-described step 3, a part of the sealing member 3 enters the hollow fiber membrane and blocks the end opening of the hollow fiber membrane. . Therefore, the length of the hollow fiber membrane bundle 6 is made longer than the length of the casing 2 in the axial direction, the sealing member 3 is inserted into the elongated portion, and then the portion is cut off. Thereby, the end opening of the hollow fiber membrane bundle 6 can be exposed from the sealing member 3 in a state where the sealing member 3 is not closed.

  <Step 6> The O-ring 4 is disposed on the sealing member 3. At this time, the O-ring 4 is disposed so as to surround the end opening of the hollow fiber membrane bundle 6 exposed from the sealing member 3. After the O-ring 4 is disposed, the liquid passing caps 9 and 10 are fixed to both ends of the casing 2. As a result, the O-ring 4 is sandwiched between the liquid passing caps 9 and 10 and the sealing member 3, and the gap between the casing 2 and the liquid passing caps 9 and 10 is sealed. The hemodialyzer 1 according to this embodiment is assembled by the above steps.

  Here, the hemodialyzer 1 according to the present embodiment and the conventional hemodialyzer 1 were compared for the presence or absence of bubbles in the sealing member 3. In addition, the hemodialyzer 1 according to the present embodiment is provided with an enlarged diameter portion 13 over the entire circumference of the inner peripheral surface of the casing 2 and the inner peripheral surface on the end side of the casing 2 as shown in FIG. 3B. Among them, an inclined surface is connected to a surface extending from the opening of the dialysate supply port 7 and dialysate discharge port 8 provided on the inner peripheral surface of the casing 2 to the end side of the casing 2 along the axial direction of the casing 2. 14 is provided, and a step 5 is provided so as to connect to other surfaces. Further, a chamfered portion 16 is provided in a portion of the step 5 that contacts the inclined surface 14. On the other hand, the conventional hemodialyzer 1 is provided with a diameter-expanded portion 13 over the entire circumference of the inner peripheral surface of the casing 2, and a step 5 is provided in the diameter-expanded portion 13 over the entire circumference. When 12 hemodialyzers 1 according to the present embodiment and 12 hemodialyzers 1 according to the prior art were prepared and the presence or absence of air bubbles in the sealing member 3 was confirmed, in the hemodialyzer 1 according to the prior art, Bubbles were found in all twelve. On the other hand, in the hemodialyzer 1 according to the present embodiment, no bubbles were observed in all twelve. From this, it is understood that air bubbles are reliably removed from the sealing member 3 in the hemodialyzer 1 according to the present embodiment.

1 hemodialyzer, 2 casing, 3 sealing member, 4 O-ring, 5 steps, 6 hollow fiber membrane bundle, 7 dialysate supply port, 8 dialysate discharge port, 9,10 flow cap, 11, 12 blood flow Liquid port, 13 enlarged diameter portion, 14 inclined surface, 15 protruding portion, 16 chamfered portion, 17, 18 sealing cap, 19 rotating shaft, 20 bubbles.

Claims (3)

A casing having an open end, a casing having a dialysate supply port and a dialysate discharge port,
A fluid-permeable cap fixed to both ends of the casing and provided with a blood fluid port;
A hollow fiber membrane bundle housed in a casing;
The ends of the hollow fiber membrane bundle are fixed by filling the gaps between the ends of the hollow fiber membranes, and are fixed to the casing inner peripheral surface on the end side of the casing from the dialysate supply port and dialysate discharge port. Sealing member,
An O-ring sandwiched between the liquid-permeable cap and the sealing member;
A hemodialyzer comprising:
Of the inner peripheral surface of the casing, the surface to which the sealing member is fixed is provided with an enlarged diameter portion in which the inner diameter on the end side of the casing is larger than the central portion side,
An inclined surface connected to the inner peripheral surface of the casing is formed on the bottom surface of the expanded diameter portion.
A hemodialyzer characterized by that. The hemodialyzer according to claim 1, wherein
The expanded diameter part is provided over the entire circumference of the inner peripheral surface of the casing,
Of the inner peripheral surface on the casing end side, the inclined surface is connected to a surface extending from the opening of the dialysate supply port and dialysate discharge port provided on the casing inner peripheral surface to the casing end portion along the axial direction of the casing. Is provided,
Of the inner peripheral surface on the casing end side, connected to a surface other than the surface extending from the opening of the dialysate supply port and dialysate discharge port provided on the casing inner peripheral surface to the casing end side along the axial direction of the casing The hemodialyzer is characterized in that a step is provided.   3. The hemodialyzer according to claim 2, wherein a chamfered portion is provided in a portion of the step which is in contact with the inclined surface.

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