Patent Application
20140378292
This invention relates to a blood component separation device having a centrifugal separator including a stator provided with an inlet and an outlet of blood or a blood component and a rotor provided rotatably with respect to the stator, and to a centrifugal separator used in the device.
Conventionally, blood collection is performed by two blood collection methods: whole blood collection and blood component collection. The blood component collection is separated to plasma collection and platelet collection. When platelet is necessary for treatment, a method for collecting platelet only and returning the other components to a blood donor is preferable. In order to take out platelet from blood, a blood component separation device provided with a centrifugal separator is used.
A centrifugal separator described in Patent Literature 1 includes a stator provided with an inlet and an outlet of blood or a blood component and a rotor provided rotatably with respect to the stator. The rotor of the centrifugal separator is rotated with respect to the stator inside the blood separation device. At this time, a ring on rotor side and a ring on stator side are in contact with and slide on each other, so that abnormal noise is generated. It is disclosed that the technique of Patent Literature 1 can prevent generation of abnormal noise by providing a damping member on the outer peripheral of the stator and providing an elastic body at a part of attaching the ring on rotor side.
Patent Literature 1: JP 2006-247217 A
However, the centrifugal separator using the technique of Patent Literature 1 still has the following issue.
In order to centrifuge blood by a centrifugal separator, priming of anticoagulant on the inner surface of tubes or the centrifugal separator where blood passes is necessary before introducing blood therein. Thereafter, blood is introduced into the centrifugal separator for centrifugation. With the technique of Patent Literature 1, abnormal noise can be reduced when blood is in the centrifugal separator, but it has an issue that noise around the high frequency band (high-pitched noise) is generated when the centrifugal separator is rotated in a process of priming anticoagulant. The high-pitched noise is not generated by all centrifugal separators and the incidence of noise generation is low. However, high-pitched noise is confusing with mechanical noise and causes an issue of imparting anxiety to an operator and a blood donor.
The present invention is made in view of the above situations and an object thereof is to provide a blood separation device that does not generate high-pitched noise even when a centrifugal separator is rotated before blood is introduced into the centrifugal separator. Solution to Problem
In order to achieve the above-described object, a blood component separation device as one aspect of the present invention is structured as follows.
(1) A blood component separation device comprises a centrifugal separator including a stator provided with an inlet and an outlet of blood or a blood component and a rotor provided rotatably with respect to the stator, wherein a rotating and sliding portion between the stator and the rotor is sealed by pressing with predetermined pressing force, and the predetermined pressing force is 500 grams or less.
(2) In the blood component separation device described in (1), it is preferable that the rotor include an annular fixing ring, the stator include a resin ring and a ring cap that holds the resin ring, the resin ring being in contact with the fixing ring and sliding thereon, the ring cap apply the predetermined pressing force to the resin ring when the centrifugal separator is set in the blood component separation device, and a rubber hardness of the ring cap be between 60 and 66 inclusive.
(3) In the blood component separation device described in (2), it is preferable that stick-slip of the fixing ring with respect to the resin ring be suppressed when the rotor is rotated in a state where blood is introduced into the centrifugal separator.
Alternatively, in order to achieve the above-described object, a centrifugal separator according to another aspect of the present invention is structured as follows.
(4) A centrifugal separator comprises a stator provided with an inlet and an outlet of blood or blood component and a rotor provided rotatably with respect to the stator and is used in a state where the centrifugal separator is set in a blood component separation device, wherein the rotor includes an annular fixing ring, the stator includes a resin ring and a ring cap that holds the resin ring, the resin ring being in contact with the fixing ring and sliding thereon, the ring cap applies predetermined pressing force to the resin ring when the centrifugal separator is set in the blood component separation device, and a rubber hardness of the ring cap is between 60 and 66 inclusive so as to set the predetermined pressing force to 500 grams or less.
Since the blood component separation device according to the present invention is structured as described above, the blood component separation device provides operation and effect to be described below.
The inventor of the present invention attempted various measures to prevent generation of high-pitched noise by changing roughness of the rotating and sliding portion between the stator and the rotor, for example. However, high-pitched noise generation couldn't be suppressed to none. Finally, the inventor found that high-pitched noise generation could be suppressed by setting the rubber hardness of the ring cap to between 60 and 66 inclusive. The reason will be described below.
According to the structure described in (1) above, stick-slip phenomenon on the sliding surface generated by the rotor with respect to the stator can be suppressed, and thus high-pitched noise generation can be suppressed.
Conventionally, the rotating and sliding portion has been pressed by high pressing force in order to enhance sealing performance. The inventor of the present invention has found that stick-slip is therefore generated and high-pitched noise is generated upon slipping. The inventor has therefore considered that high-pitched noise generation can be suppressed if stick-slip phenomenon can be suppressed and confirmed the fact by an experiment.
In addition, the inventor of the present invention has found that that pressing force at the rotating and sliding portion between the stator and the rotor can be 500 grams or less by setting the rubber hardness to 66 or less by the structure described in (2) above.
More specifically, in the conventional blood component separation device, the rotor and the stator of the centrifugal separator has been pressed for a predetermined distance when the centrifugal separator is fitted. Because of this, the predetermined pressing force becomes 500 grams or more when the rubber hardness of the ring cap is 66 or more and thus elastic deformation of the ring cap is small. Thus, stick-slip is generated. In addition, since the rubber hardness of 60 or less degrades sealing performance, the rubber hardness is set to 60 or more.
Further, the structure described in (3) above can suppress high-pitched noise generation.
In addition, the centrifugal separator according to the present invention is structured as described above, and thus provides operation and effect to be described below.
According to the structure described in (4) above, stick-slip generated by the fixing ring with respect to the resin ring can be suppressed and thus high-pitched noise generation can be suppressed when the rotor is rotated in a state where blood is introduced into the centrifugal separator.
First, an embodiment of the present invention will be described with reference to accompanying drawings.
The collection needle 11 for collecting whole blood from a blood donor is connected to one end of the donor tube 12. The other end of the donor tube 12 is connected to a first port 13a of the first blood pump 13. The initial flow blood collection bag 82 is connected to a blood collection needle from a branch part provided on the donor tube 12 by the initial flow blood collection line 88. The initial flow blood collection bag 82 further includes the sampling port 85 for transporting collected initial flow blood to a container for examination, which is not illustrated. The sampling port 85 includes a needle part 83, a body section 86, and a cover part 84 that covers the needle part. In addition, on the initial flow blood collection line 88, a clamp 90 for opening/closing the line is provided. The tube 44 connected to a second port 13b of the first blood pump 13 is connected to a first port 16a of the first on-off valve 16. A pressure sensor 14 is connected to the donor tube 12. The tube 60 connected to a second port 16b of the first on-off valve 16 is branched into two tubes. The tube 45, which is one of the tubes, is connected to an output port 18b of the second blood pump 18. The tube 46, which is the other of the tubes, is connected to the inlet 19a of the centrifugal bowl 19, which is a centrifugal separator. More specifically, the collection needle 11 and the inlet 19a of the centrifugal bowl 19 are connected by the first line (the donor tube 12, the first blood pump 13, the tube 44, the first on-off valve 16, the tube 60, and the tube 46).
The tube 47 connected to the outlet 19b of the centrifugal bowl 19 is branched into two tubes. The tube 48, which is one of the tubes, is connected to an input port 24a of the second on-off valve 24, and the tube 49, which is the other of the two tubes, is further branched to be described later. In the middle of the tube 47 connected to the outlet 19b of the centrifugal bowl 19, a turbidity sensor 21, and a pressure sensor 22 are attached. In addition, in the peripheral part of the part where the centrifugal bowl 19 is attached, an interface sensor 38 for detecting the interface position of a buffy coat layer formed in the centrifugal bowl 19 is attached. An output port 24b of the second on-off valve 24 is connected to an input port 25a of the plasma bag 25 by the tube 58. More specifically, the outlet 19b of the centrifugal bowl 19 and the input port 25a of the plasma bag 25 are connected by the second line (the tube 47, the tube 48, the second on-off valve 24, and the tube 58).
An output port 25b of the plasma bag 25 is connected to an input port 18a of the second blood pump 18 by the tube 59. The output port 18b of the second blood pump 18 is connected to the tube 45. More specifically, the output port 25b of the plasma bag 25 and the first line are connected by the third line (the tube 59, the second blood pump 18, and the tube 45). Thus, the plasma bag 25 is connected in a manner such that the plasma bag 25 communicates with the inlet 19a and the outlet 19b of the centrifugal bowl 19. The communication is open/shut off by operation of the second blood pump 18 and the second on-off valve 24.
The tube 49 branched off from the tube 47 is branched into two tubes as described above. The tube 51, which is one of the tubes, is connected to the air bag 28 through the third on-off valve 26. The tube 52, which is the other of the tubes, is connected to the platelet intermediate bag 29 through the fourth on-off valve 27. More specifically, the outlet 19b of the centrifugal bowl 19 and the air bag 28 are connected by the fourth line (the tube 47, the tube 49, the tube 51, and the third on-off valve 26), the outlet 19b of the centrifugal bowl 19 and the platelet intermediate bag 29 are connected by the fifth line (the tube 47, the tube 49, the tube 52, and the fourth on-off valve 27). Thus, the platelet intermediate bag 29 is connected so as to selectively communicate with the outlet 19b of the centrifugal bowl 19 and the communication is open/shut off by operation of, the second on-off valve 24, the third on-off valve 26, and the fourth on-off valve 27.
A tube 55 running out from the platelet intermediate bag 29 is branched into two tubes. A tube 56, which is one of the tubes, is connected to an input port 30a of a fifth on-off valve 30, and a tube 57, which is the other of the tubes, is connected to an output port 34b of a third blood pump 34. An input port 34a of the third blood pump 34 is connected to a platelet storage liquid bottle, which is not illustrated, by a platelet bottle needle 35 through a second sterile filter 40. An output port 30b of the fifth on-off valve 30 is connected to a platelet bag 32 through a leukocyte removing filter 31. To the platelet bag 32, an air bag 33 is connected.
Meanwhile, in the middle of the donor tube 12, an output port 36b of an ACD pump 36 is connected. An input port 36a of the ACD pump 36 is connected to an output port 37b of a first sterile filter 37. An input port 37a of the first sterile filter 37 is connected to an ACD storage bottle by an ACD bottle needle 39.
To a control unit, which is not illustrated, the first blood pump 13, the second blood pump 18, the third blood pump 34, the centrifugal bowl driving device 15, the ACD pump 36, the turbidity sensor 21, the interface sensor 38, the pressure sensor 22, the first on-off valve 16, the second on-off valve 24, the third on-off valve 26, the fourth on-off valve 27, and the fifth on-off valve 30 are electrically connected. The centrifugal bowl 19 is arranged on the centrifugal bowl driving device 15, which is a rotatably driving unit, and rotatably driven.
Preferable constituent materials of the tubes include polyesters such as polyvinyl chloride, polyethylene, polypropylene, PET, and PBT and various thermoplastic elastomers such as ethylene vinyl acetate copolymer (EVA), polyurethane, and polyester elastomer, for example. Among them, polyvinyl chloride is particularly preferable. Polyvinyl chloride can provide sufficient flexibility and easy handling and is suitable for closing by a clamp or the like.
As a constituent material of the bags, a polymer obtained by polymerizing or copolymerizing soft olefins or diolefins such as polyvinyl chloride, polyolefin, ethylene, propylene, butadiene, and isoprene, in which DEHP is used as a plasticizer may be used. In addition, any combination thereof such as an ethylene vinyl acetate copolymer (EVA), and a polymer blend of EVA and various thermoplastic elastomers may be used. Further, PET, PBT, PCGT, etc. can be used. Among them, polyvinyl chlorides are particularly preferable. For containers for storing platelet, a material having excellent gas permeability is preferable in order to improve storability of platelet. Thus, for containers for storing platelet, polyolefin, DnDP-plasticized polyvinyl chloride, etc. may be preferably used or a sheet having a reduced thickness may be preferably used.
At a part that is outside the inlet pipe 62 and inside the cover 61, a ring cap 121 made of silicone rubber is provided. It is preferable that the ring cap 121 be appropriately elastic and be made of a material having corrosion resistance. The ring cap 121 is formed in a cap shape, a small diameter side 121a is fixed to the bowl head 74, and a large diameter side 121b is secured to the outer diameter of a resin ring 122 such that the large diameter side 121b is pressed by the resin ring 122 and a rib 742. The rib 742 is provided toward the inner circumferential direction on the inner surface of the cover 61 intermittently. A shoulder portion 743 connected to a part where the cover 61 and a neck portion 741 are connected is formed in a gently curved shape. The resin ring 122 is a ring made of a hard resin such as phenol resin and is formed substantially annularly. The resin ring 122 is arranged to abut on a fixing ring 125 to be described later and is held on the stator 70 side.
The rotor 75 includes a side wall 73 made of polycarbonate and formed in a bell shape, a shoulder portion 76 having a reduced diameter at one end of the fixing ring 125, and a bottom plate 71 that is fitted to close the other end of the fixing ring 125. Inside the fixing ring 125, the rotor 75 includes an outer shell 78 and an inner shell 79. The outer shell 78 is in a bell shape and is provided with a support part 731 on its end intermittently. The rotor 75 is structured such that the support part 731 abuts on the inner periphery side of the shoulder portion 76. The side wall 73 is in a funnel shape and structured to fit with the outer shell 78 on both ends thereof. On an end of the shoulder portion 76, the fixing ring 125 made of ceramic, which has high sliding durability, such as alumina is fitted, and the fixing ring 125 is structured to abut on the above-described resin ring 122. Between the lower surface of the inner shell 79 and the upper surface of the bottom plate 71, a substantially discoid bottom flow path 130 is formed.
The bottom plate 71 is a substantially discoid member formed with a depressed part in the central portion of the bottom plate 71. The depressed part is formed to receive blood that has flown down from the in-pipe flow path 621. In addition, between the lower surface of the inner shell 79 and the upper surface of the bottom plate 71, a bottom flow path 130 expanding in substantially discoid shape is formed. The bottom flow path 130 formed between the inner shell 79 and the bottom plate 71 communicates with the in-pipe flow path 621 of the inlet pipe 62. The bottom flow path 130 also communicates with a blood storage space 77 formed by the outer peripheral of the outer shell 78 and the inner peripheral of the side wall 73. The blood storage space 77 has a tapered shape having an inner diameter gradually reduced toward the outlet 19b side. Volume of the blood storage space 77 is preferably about 50 to 1000 ml and more preferably about 100 to 300 ml.
The seal mechanism portion 120 has a function of sealing between the stator 70 and the rotor 75 when they abut. On the stator 70 side, the ring cap 121 and the resin ring 122 are provided and on the rotor 75 side, the fixing ring 125 is provided. When the resin ring 122 and the fixing ring 125 abut, the sealing function is exerted. The centrifugal bowl 19 arranged in the centrifugal tank 110 is pressed against the centrifugal bowl driving device 15 side due to the shape of the shoulder portion 743 abutting on the lid portion 112 when the lid portion 112 is closed. As a result, the bottom plate 71 is, for example, stuck to the centrifugal bowl driving device 15. Since the centrifugal bowl driving device 15 is coupled to a rotatably driving device, the centrifugal bowl driving device 15 can rotate the rotor 75 abutting thereon.
The centrifugal bowl 19 and the blood component separation device 100 configured as described above can centrifuge whole blood collected from the blood donor and collect platelet PLT. Strictly speaking, high concentration platelet PLT solution containing plasma PPP, which is difficult to separate, in addition to platelet PLT can be collected. Next, a flow of blood inside the centrifugal bowl 19 will be briefly described.
When blood flows from the inlet 19a, centrifugal force caused by rotation of the rotor 75 forms a red blood cell RBC layer, a white blood cell WBC layer, a buffy coat BC layer, a platelet PLT layer, and a plasma PPP layer in the blood storage space 77 formed by the outer shell 78 and the side wall 73 in a descending order of specific gravity from the outer side. At this time, since white blood cell WBC and platelet PLT have close specific gravities, it is difficult to separate them. Therefore, a buffy coat BC layer containing white blood cells WBC and platelets PLT is formed. Breakdown of whole blood is typically plasma PPP about 55%, red blood cell RBC about 43.2%, white blood cell WBC about 1.35%, and platelet PLT about 0.45%. In the centrifugal bowl 19, the outflow passage 63 formed a little upper than the middle point of the inlet pipe 62 is formed in the inner peripheral portion. Thus, in the blood storage space 77, whole blood flows from the plasma PPP formed on the inner peripheral, through the outlet 19b, and to the outside of the centrifugal bowl 19.
Next, the operation of the blood component separation device configured as described above will be described with reference to
First, The ACD pump 36 and the first blood pump 13 are driven to supply ACD solution for preventing coagulation of blood to the centrifugal bowl 19 through the first on-off valve 16, which is open, and a priming process (first process) of the centrifugal bowl 19 is performed. Priming is a process of applying ACD solution on parts inside the donor tube 12, a first pump, and the centrifugal bowl 19 where blood comes in contact so as to prevent coagulation when blood flows therethrough. ACD solution is supplied from the ACD storage bottle, which is not illustrated and to which the ACD bottle needle 39 is connected. From the priming process, the centrifugal bowl 19 is rotated at a predetermined speed of rotation. When the priming process is completed, the collection needle 11 is punctured into the blood donor as illustrated in
When whole blood is supplied to the centrifugal bowl 19 in rotation, air inside the centrifugal bowl 19 is pushed by plasma PPP and the air flows out through an outflow portion positioned on the inner peripheral of the centrifugal bowl 19 as illustrated in
Next, when the turbidity sensor 21 detects change of fluids flowing in the tube 47 from air to plasma PPP, the third on-off valve 26 is closed as illustrated in
Next, when some amount of plasma PPP (30 ml in the embodiment) is stored in the plasma bag 25, the second blood pump 18 is driven as illustrated in
Next, when the interface sensor 38 detects that the interface between buffy coat BC and platelet PLT comes at a predetermined position, the first on-off valve 16 is closed as illustrated in
Next, after the circulation flow process for a certain time, the acceleration process (fifth process) illustrated in
The concentration of discharged platelets PLT, white blood cells WBC, and red blood cells RBC changes as follows. First, platelets PLT are discharged, and discharged amount of platelets PLT tends to gradually increase, exceed the max rate, and then gradually decrease. Similarly, the discharged amount of white blood cells WBC gradually increases, exceeds the max rate, and then gradually decreases. When the turbidity sensor 21 detects platelet PLT solution, the second on-off valve 24 is closed and the fourth on-off valve 27 is opened as illustrated in
Next, when the concentration of platelets PLT detected by the turbidity sensor 21 is less than a predetermined amount, the process moves to a retransfusion process illustrated in
Upon completion of the retransfusion, rotation of the centrifugal bowl 19 is started and the first blood pump 13 is normally rotated again to restart blood collection. The cycle from
Next, the fifth on-off valve 30 is opened to inject platelet PLT solution stored in the platelet intermediate bag 29 into the platelet bag 32 through the leukocyte removing filter 31. At this time, air existing in the platelet bag 32 moves to the air bag 33. After confirming that the whole of platelet PLT solution stored in the platelet intermediate bag 29 is discharged, the third blood pump 34 is driven to inject platelet storage liquid to the platelet bag 32 by the platelet bottle needle 35 connected to a platelet storage liquid bottle through the second sterile filter 40. Thereafter, two tubes of the platelet bag are sealed. Through this process, the platelet bag 32 storing high concentration platelet PLT solution is completed.
Because the centrifugal bowl 19 according to the embodiment is structured as described above, operation and effect to be described below are provided.
First, the centrifugal bowl 19 according to the embodiment can suppress high-pitched abnormal noise generation in the priming process. In the blood component separation device 100 including the centrifugal bowl 19 including the stator 70 provided with the inlet 19a and the outlet 19b of blood or a blood component and the rotor 75 provided rotatably with respect to the stator 70, the centrifugal bowl 19 according to the embodiment seals the rotating and sliding portion between the stator 70 and the rotor 75 by pressing the portion with a predetermined pressing force. The predetermined pressing force is 500 grams or less.
More specifically, the structure of the seal mechanism portion 120 is characterized in that the rotor 75 includes the annular fixing ring 125, the stator 70 includes the resin ring 122, which is a resin ring in contact with the fixing ring 125 and sliding thereon, and the ring cap 121 holding the resin ring 122, the ring cap 121 applies a predetermined pressing force to the resin ring 122 when the centrifugal bowl 19 is set in the blood component separation device 100, and the rubber hardness of the ring cap 121 is between 60 and 66 inclusive.
As described in the description of object, abnormal noise is unfortunately generated in priming, performed in the above-described first process, for applying ACD solution. The applicant has investigated to specify a cause of the abnormal noise from various viewpoints including the structure of the centrifugal tank 110, friction of the seal mechanism portion 120, and pressing pressure and vibration adsorption of the centrifugal bowl 19. As a result, the applicant has confirmed that abnormal noise is generated due to a stick-slip phenomenon, which occurs in the seal mechanism portion 120. It has been confirmed that a stick-slip phenomenon occurs in a part where the resin ring 122 and the fixing ring 125 abut. It is considered that the stick-slip phenomenon generates chattering during relative movement of the fixing ring 125 and the resin ring 122, and the chattering appears as vibration or abnormal noise. More specifically, it has been found that during movement of the fixing ring 125 with respect to the resin ring 122, the stick-slip phenomenon in which sticking and moving are repeated is generated under certain conditions, and the stick-slip phenomenon causes to generate abnormal noise.
It is considered that the stick-slip phenomenon is affected by friction generated between the fixing ring 125 and the resin ring 122. Therefore, the applicant performed an experiment while changing the hardness of the ring cap 121 supporting the resin ring 122.
The first group g1 indicating data of vibration acceleration generated between the fixing ring 125 and the resin ring 122 is experiment data when the hardness of the ring cap 121 is set in a rough range from 55 to 59. The second group g2 includes data when the hardness of the ring cap 121 is set to 60, the third group g3 includes data when the hardness is set to 63, the fourth group g4 includes data when the hardness is set to 66, the fifth group g5 includes data when the hardness is set to 68, and the sixth group g6 includes data when the hardness is set to set to 70. The amounts provided as the rubber hardness of the ring cap 121 indicate standard hardness measured by the testing method specified in JIS K6253, which is a result of a test using a durometer. The rubber hardness of the first to sixth groups g1 to g6 is adjusted in the stage of raw material, and the rubber hardness of the ring cap 121 is uniform. In this manner, the rubber hardness of the ring cap 121 and force of pressing the centrifugal bowl 19 were changed and vibration of the centrifugal tank 110 was detected.
As a result of the experiment, vibration causing abnormal noise was not detected under conditions where the pressing pressure is 500 grams or less as illustrated in
It is considered that the correlation between the rubber hardness of the ring cap 121 and the pressing pressure of the centrifugal bowl 19 is generated due to the way of holding the centrifugal bowl 19 with respect to the blood component separation device 100. Specifically, upon disposing the centrifugal bowl 19 in the blood component separation device 100, the centrifugal bowl 19 is fixed by suction at a predetermined position of the centrifugal bowl driving device 15, which is arranged inside the centrifugal tank 110, and the lid portion 112 is closed. The relation between the centrifugal bowl 19 and the lid portion 112 is described above. That is, the size relationship of the centrifugal bowl 19 and the lid portion 112 is set such that the lid portion 112 interferes with the shoulder portion 743 of the centrifugal bowl 19 in a state where the centrifugal bowl 19 is arranged in the centrifugal bowl driving device 15. Therefore, closing of the lid portion 112 pushes the centrifugal bowl 19 down toward the centrifugal bowl driving device 15 along the taper of the shoulder portion 743 by a few millimeters as a result. The distance by which the centrifugal bowl 19 is pushed down is absorbed by the seal mechanism portion 120. More specifically, the distance is absorbed by deformation of the ring cap 121 as illustrated in
As described above, the pressing pressure of the ring cap 121 could be changed by adjusting the rubber hardness of the ring cap 121, and generation of the above-described abnormal noise due to the stick-slip phenomenon could be prevented by setting the rubber hardness to about 66 or less. It is considered that the stick-slip phenomenon causes repeated moving and sticking of the resin ring 122 with respect to the fixing ring 125 when the fixing ring 125 rotates and moves with respect to the resin ring 122. It is then considered that the moving and sticking caused generation of high-pitched abnormal noise depending on the relationship with the speed of rotation of the centrifugal bowl driving device 15. Therefore, the friction force generated between the resin ring 122 the fixing ring 125 could be changed and thus generation of abnormal noise could be prevented by varying the rubber hardness of the ring cap 121. However, in relation to an issue of sealing performance of the seal mechanism portion 120, appropriate sealing performance may not be provided with the ring cap 121 having too low rubber hardness. Water leak was checked in a test of rotating the centrifugal bowl 19 containing artificial blood and surfactant, and water leak was not found in any of the first to sixth groups g1 to g6. However, in consideration anticipating the safety factor, it is considered that the preferable rubber hardness of the ring cap 121 is 60 or more.
From the consideration, the appropriate hardness of the ring cap 121 is roughly between 60 and 66 inclusive. When the ring cap 121 is structured as described above, the pressing pressure of the centrifugal bowl 19 can be 500 grams or less and abnormal noise generated from the centrifugal bowl 19 can be suppressed. High-pitched abnormal noise generated from the centrifugal bowl 19 is confusing with mechanical noise and may impart a sense of anxiety to a blood donor lying right next to the blood component separation device 100 or an operator who collects blood. However, through the use of the centrifugal bowl 19 according to the embodiment, such anxiety can be resolved.
The specific embodiment of the present invention has been described in detail, but the present invention is not limited to the above-described embodiment and various applications are possible.
For example, change of the centrifugal bowl 19 is not prevented as long as the essential structure of the seal mechanism portion 120 is the same. In addition, change of the structure of the blood component separation device 100 is not prevented. Further, change of the material of the centrifugal bowl 19, which has been exemplified, is not prevented without departing from the spirit of the invention.
61 cover
62 inlet pipe
63 outflow passage
70 stator
71 bottom plate
72 shoulder portion flow path
73 side wall
74 bowl head
75 rotor
76 shoulder portion
77 blood storage space
78 outer shell
79 inner shell
100 blood component separation device
110 centrifugal tank
112 lid portion
120 seal mechanism portion
121 ring cap
122 resin ring
125 fixing ring
130 bottom flow path
621 in-pipe flow path
731 support part
741 neck portion
742 rib
743 shoulder portion
BC buffy coat
PLT platelet
PPP plasma
RBC red blood cell
WBC white blood cell
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-055878 | Mar 2012 | JP | national |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2013/054491 | Feb 2013 | US |
| Child | 14481603 | US |
