Rotor and centrifuge using same

Abstract

Provided is a continuous centrifugation machine that facilitates gradual switching of the capacity of centrifugation spaces, by the size of attached fins. A rotor for the continuous centrifugation machine comprises: a substantially cylindrical core main body 31 having a groove 37 for the attachment of a plurality of fins, that continues in the axial direction on the outer peripheral surface; a plurality of fins 40 that are attached so as to protrude to the outside in the radial direction, from the outer peripheral surface of the core main body 31; and a cylindrical rotor body 11. A plurality of attached fins (40, 50) are provided that have sections, protruding further to the outside in the radial direction than the outer peripheral surface of the core main body, that have differing widths in the circumferential direction. The present invention is configured such that the capacity of the centrifugation spaces S1–S6 can be changed by an operator selecting one of the plurality of fins 40,50 and attaching the selected fin to the core main body 31.

Description

[Technical field]

[0001] The present invention relates to a centrifuge that separates particles in a liquid sample by centrifuging the sample within the rotor while the rotor is rotating. [Background technology]

[0002] A centrifuge separates particles that do not or have difficulty settling in a normal gravitational field by centrifugal force, and examples of the particles to be separated include viruses and bacteria. Viruses and bacteria are essential raw materials for the production of medicines and vaccines, and so-called continuous centrifuges are widely used as equipment for separating and purifying raw materials in the production process of these. A continuous centrifuge has a sample supply unit that enables a sample to be continuously supplied to a rotor that rotates at high speed. The sample supply unit has a liquid delivery pump for supplying the sample, and continuously supplies the sample from the inlet of the rotor to the inside while the rotor is rotating under the control of a control device, and discharges it from the outlet of the rotor.

[0003] In a centrifuge, the rotation speed (rpm) of the motor that rotates the rotor is set, and when a sample is introduced into the rotor, the rotor is rotated at this rotation speed for a set period of time, applying a strong centrifugal force to the sample inside the rotor. The acceleration (centrifugal acceleration) at this time can be tens of thousands of G in units of gravitational acceleration G, and in order to achieve a high rotation speed of the rotor, the rotor is often placed in a rotor chamber that is evacuated to a vacuum. After the centrifugation process, the samples are separated according to their density.

[0004] When such a centrifuge is used to centrifuge a sample that is to be used as a raw material for a vaccine, a portion corresponding to a desired density is selectively extracted after centrifugation. The configuration of such a continuous centrifuge is described in, for example, Patent Document 1. Here, the shape of the core body 331 of the conventional rotor disclosed in Patent Document 1 is explained using FIG. 10. FIG. 10(A) is a top view of the core body 331 and the fins 340. In the continuous centrifuge of Patent Document 1, in order to suppress adhesion between the rotor body 311 (see (B) for the symbol) and the core body portion, the fins 340 are configured as separate bodies separate from the core body 331, and each fin 340 is attached to the core body 331. The shape after the fins 340 are attached has an appearance similar to the shape of the rotor core of a centrifuge prior to Patent Document 1, and is the same as the shape of the fins integrally molded with the core body. The core body 331 has a fin attachment groove 337 formed therein. Fin 340 has a fin tip 342, and is attached such that fin base 341 is inserted into fin mounting groove 337, allowing slight radial movement.

[0005] 10B is a diagram showing the state of the fins 340 when the rotor is rotating at high speed. During centrifugation processing, the rotor body 311 expands slightly due to centrifugal force, but at the same time, the fins 340 also move outward due to centrifugal force, so that the tips (radial outer peripheral surfaces) of the fin tips 342 come into contact with the inner surface of the rotor body 311. At this time, the movable range 345 of the fins 340 is, for example, about 0.1 mm to 0.5 mm. No precipitate P gets between the tips of the fin tips 342 and the inner surface of the rotor body 311, and each centrifugal separation space S is maintained in a sealed state by the fins 340, thereby suppressing the generation of turbulence in the sample (liquid) in the separation space S.

[0006] 10(C) when the rotor stops rotating from this state, the rotor body 311 contracts slightly from the state of FIG. 10(B), and during this contraction, the fins 340 move inward while the fin tips 342 are in contact with the inner surface of the rotor body 311. As a result, the state in which the tips of the fins 340 and the inner surface of the rotor body 311 are in contact with each other is maintained from the time of the centrifugation process to the end of the process. When disassembling the rotor, the fins 340 can move in the direction of the rotation axis (up and down). Therefore, after the centrifugation operation is completed, the sample (liquid) after the precipitate P is separated in the centrifugation space S is removed in the reverse order of the introduction of the sample, and the rotor is disassembled. During this disassembly, the lower rotor cover (not shown) of the rotor is removed, and with the core body 331 attached to the rotor body 311, the user can move the fins 340 downward to remove the fins 340 from the core body 331. After that, the core body 331 and the upper rotor cover are separated, and the rotor can be easily disassembled. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2017-131873 A [Patent Document 2] JP 2006-43618 A Summary of the Invention [Problem to be solved by the invention]

[0008] In the case of a continuous centrifuge, a preliminary test for determining the optimal conditions for continuous centrifugation for production may be performed by partially modifying and scaling down an actual continuous centrifuge for production. In this case, it is necessary to prepare multiple cores or centrifuges according to the amount of sample to be separated, which requires introduction costs and space for installing multiple centrifuges. In addition, in the technology of Patent Document 2, a small-capacity core body is prepared in addition to a standard core body housed inside the rotor body. However, preparing a small-capacity core body increases costs, and even if a small-capacity core body is prepared, if the radial depth of the flow path is different between a core for separating a small amount of sample (a core for preliminary testing) and a core for separating a large volume of sample (a core for production), the time required for sample separation will differ, so the flow rate at which the sample is sent into the rotor must be adjusted. In addition, the operating conditions for the core that separates a large volume of sample (production core) are calculated based on the operating conditions of the core that separates a small amount of sample (preliminary test core). However, in some cases, fine adjustments to the operating conditions are required, and it is time-consuming to find the optimal conditions.

[0009] The present invention has been made in consideration of the above-mentioned background, and its object is to provide a rotor for a centrifuge in which the fin portion of the core body is configured to be detachable and the capacity of the centrifugal separation space can be changed in stages depending on the size of the fins to be attached, and a centrifuge using the same. Another object of the present invention is to provide a rotor for a centrifuge that enables the volume of the centrifugal separation space to be changed while maintaining the same centrifugal operation conditions, and a centrifuge using the same. Yet another object of the present invention is to provide a rotor for a centrifuge that enables the volume of the centrifugation space to be changed in a simple manner while using a common rotor body and a common core body, and a centrifuge using the same. [Means for solving the problem]

[0010] Representative features of the invention disclosed in this application are as follows. According to one feature of the present invention, a rotor for a centrifuge includes a core having a columnar core body and a plurality of fins attached to the core body so as to protrude radially from the outer circumferential surface of the core body, and a cylindrical rotor body surrounding the core, and a rotor configured such that a sample is flowed into the core body and the rotor body between both ends in the direction of the rotation axis, and the fins are detachable from the core body, and a plurality of types of fins having different circumferential widths of the parts protruding radially outward from the outer circumferential surface of the core body are prepared as the rotor. When disassembling the rotor, a user can select one of the plurality of types of fins and attach it to the core body, thereby making it possible to reduce the volume of the centrifugation space S defined between the core body and the rotor body, not only to the normal size, but also to accommodate small-volume centrifugation. The core body of the rotor is approximately cylindrical, and a plurality of fin attachment grooves are formed at equal intervals in the circumferential direction of the outer circumferential surface of the core body. The fin attachment grooves are continuously formed from the upper end to the lower end of the core body in a direction parallel to the rotation axis of the rotor. This fin is formed by an attachment portion shaped to correspond to the fin mounting groove and a protrusion that protrudes radially outward beyond the opening surface of the fin mounting groove, and the circumferential width of the protrusion is formed to be greater than the width of the fin mounting groove.

[0011] According to another feature of the present invention, the protruding portion of the fin is formed with an inner peripheral surface in contact with the outer peripheral surface of the core body and an outer peripheral surface in contact with the inner peripheral surface of the rotor body, and the area of ​​each outer peripheral surface of the fin is configured to be larger than the opening area of ​​the fin mounting groove. A sample to be centrifuged in a centrifuge is injected into the rotor body from one side in the rotation axis direction while the rotor is rotating, and discharged from the other side, and the fin and the core body are removable from the rotor body when the rotor is disassembled. In addition, regardless of the fin selected by the user, the radial distance of the centrifugal separation space S between the inside of the rotor body and the core is constant, so that even if the fin is changed, there is no change in the centrifugal acceleration force applied to the sample, and the centrifugation conditions are kept constant. The core body and the fin are made of synthetic resin or metal, and the density of the fin is configured to be smaller than the density of the core body. For example, the density of the fin is 1.2 g / cm 3If the density gradient solution is set to less than the maximum density, when centrifugation is performed while a sample is being passed through the rotor, the fins will move closer to the axis of rotation due to the density difference between the fins and the sample.

[0012] According to yet another feature of the present invention, in a rotor for a centrifuge, the rotor is provided with a cylindrical rotor for separating a sample, a centrifuge chamber in which the rotor is housed, a drive means for rotating the rotor, and a sample line for continuously supplying and discharging a sample to and from the rotor while the rotor is rotating, the rotor is configured to include a cylindrical rotor body, a core body disposed in the rotor body to form a sample path, and fins for separating the sample and detachably attached to the core body to divide the inside of the rotor body into a plurality of spaces. A fin mounting groove is formed in the core body for mounting the fin. The fin is formed to include an attachment portion having a shape corresponding to the fin mounting groove and a protruding portion protruding radially outward from the fin mounting groove, and the protruding portion is extended in the circumferential direction of the rotor beyond the range in which the fin mounting groove is formed, thereby making it possible to change the volume of the centrifugation space between the core body and the rotor body. The protruding portion of the fin has an outer surface having an arc surface having an outer diameter substantially equal to the inner diameter of the rotor body, and an inner surface of the protruding portion is formed by an arc surface that contacts the outer surface of the rotor body, and the density of the fin is configured to be smaller than the density of the core body. Using such a rotor, a continuous centrifuge having a drive unit for driving the rotor was constructed. Effect of the Invention

[0013] According to the present invention, the main body (core body) of the rotor core is configured to have detachable blades (fins), and normal blades and blades for making the centrifugation space smaller than normal are provided. By replacing the blades attached to the main body, the user can change the flow area of ​​the centrifugation space (separation chamber) without changing the radial distance of the separation space, thereby changing the volume of the separation space (separation chamber). As a result, it is possible to flexibly respond to changes in the processing capacity of a single centrifugation run, and for example, it is possible to handle small-volume test continuous centrifugation to large-volume production continuous centrifugation, so there is no need to prepare multiple core bodies and rotors. In addition, since the flow volume can be changed simply by replacing the blades without changing the radial dimensions of the main body (core body) of the rotor core, it is possible to flexibly respond to changes in the volume of the sample while keeping the centrifugation conditions the same. In this way, it is possible to derive optimal operating conditions with a small amount of experimental sample and separate a production sample (large volume) without changing the operating conditions. As a result, it is possible to flexibly respond to changes in the processing capacity of a single centrifugation run, and for example, it is possible to handle everything from trial separation to production separation, so there is no need to prepare multiple cores or continuous centrifuge units. In addition, since the flow path area can be changed simply by replacing the blades without changing the radial dimensions of the rotor core's main body (core body), it is possible to eliminate the risk of the centrifugation conditions changing due to changes in sample volume. In this way, it is possible to derive optimal operating conditions from a small amount of experimental sample and separate a production sample (large volume) without changing the operating conditions. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a perspective view showing an entire centrifuge 1 according to an embodiment of the present invention. [Diagram 2] 2 is a cross-sectional view showing a detailed structure of the centrifugal separation unit 100 in FIG. 1 and a piping diagram of a sample line. [Diagram 3] 2 is a vertical cross-sectional view of the rotor 10 of FIG. 1. [Figure 4]4A and 4B are cross-sectional views of part AA in FIG. 3, in which (A) is a cross-sectional view of a state in which a standard fin 40 is attached to the core body 31, (B) is a diagram for explaining a method of attaching the fin 40 or fin 50 to the core body 31, and (C) is a cross-sectional view of part AA in a state in which a fin 50 compatible with small capacity is attached to the core body 31. [Diagram 5] 1A is a top view of the core body 31 of this embodiment with a fin 50 for small capacities attached, FIG. 1B is a partial enlarged view of FIG. 1A, and FIG. 1C is a partial top view of the core body 31 with a fin 60 for medium capacities attached. [Figure 6] 5A is an oblique view showing the overall shape of the standard fin 40 shown in FIG. 4, FIG. 5B is an oblique view showing the overall shape of the small-capacity fin 50 shown in FIG. 4, and FIG. 5C is a horizontal cross-sectional view (schematic diagram) for explaining the state in which the rotor is rotated at high speed with the small-capacity fin 50. [Figure 7] 1A and 1B are diagrams showing a small-capacity fin 70 according to a first modified example of the present embodiment, in which (A) is a horizontal cross-sectional view and (B) is a perspective view showing the entire structure. [Figure 8] 1A and 1B are diagrams showing a fin 80 for small capacity according to a second modified example of the present embodiment, in which (A) is a horizontal cross-sectional view and (B) is a perspective view showing the entire structure. [Figure 9] 4 is a vertical sectional view of a rotor 10A according to a second embodiment of the present invention. FIG. [Figure 10] (A) is a top view showing the shape of core body 331 of a conventional rotor, (B) is a diagram showing the state of fins 340 when the rotor is rotating at high speed, and (C) is a diagram showing the state of fins 340 when the rotor decelerates and stops. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS EXAMPLES

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following drawings, the same parts are given the same reference numerals, and repeated explanations will be omitted. In addition, in this specification, the front-rear and up-down directions will be described as the directions shown in the drawings.

[0016] FIG. 1 is a perspective view showing the entire centrifuge (continuous centrifuge) 1 according to this embodiment. As shown in FIG. 1, the centrifuge 1 is capable of continuously supplying and discharging a sample from the outside into the rotor 10 while the rotor 10 is rotating, and is widely used in vaccine production processes and the like. The centrifuge 1 is composed of two main parts, a centrifugal separation section 100 and a control device section 200. The centrifugal separation section 100 and the control device section 200 are connected by a group of wiring and piping 250.

[0017] The centrifugal separation unit 100 is configured to include a cylindrical chamber 101 that serves as a centrifuge chamber, a base 110 that supports the chamber 101, a rotor 10 that is freely inserted and removed inside the chamber 101 and rotates at high speed, a drive unit 130 that is disposed above the chamber 101 and rotates the rotor 10 while hanging it, a lower rotation support unit 140 that is attached to the lower side of the chamber 101, a lift 160 and an arm 161 that move the drive unit 130 up and down and back and forth, and a sample line (described later in FIG. 2) that continuously supplies and discharges a sample or a sterilizing liquid to the rotor 10. The rotor 10 is configured to include a cylindrical rotor body 11, an upper rotor cover 19 that is attached to the upper side of the rotor body 11 by a screw type, and a lower rotor cover 24 that is attached to the lower side of the rotor body 11 by a screw type. A lower shaft 141 is connected to the lower rotor cover 24, and these components form a rotating container that rotates at high speed.

[0018] Since the rotor 10 is rotated at high speed, the inside of the chamber 101 is kept at a reduced pressure during centrifugation operation in order to suppress heat generation due to windage loss with the atmosphere and frictional heat during operation. In order to keep the inside of the chamber 101 in which the rotor 10 is housed at a reduced pressure, an exhaust port (not shown) for discharging air from inside the chamber 101 is formed in the body of the chamber 101 and a vacuum pump (not shown) is connected to it. The chamber 101 is fixed to a base 110 by a plurality of bolts 111, and the base 110 is fixed to the floor surface by a plurality of bolts 112.

[0019] The control device unit 200 accommodates a cooling device (not shown) for cooling the entire centrifuge chamber inside the chamber 101, a vacuum pump (not shown) for reducing the pressure in the centrifuge chamber inside the chamber 101, a lift drive device (not shown) for driving a lift 160 and an arm 161 for moving the rotor 10 to a predetermined location, and a control device (not shown) for driving and controlling the rotor 10. The control device is composed of electronic circuits including a microcomputer (not shown) and a storage device, and controls the rotation of the rotor 10 and also controls all of the devices included in the centrifuge 1. An operation panel 205 is disposed on the upper part of the control device unit 200, and serves both as an input unit for a user to input information and as a display unit for displaying the operating status and the like to the user. For example, a touch sensor type liquid crystal display device can be used as the operation panel 205, and an audio output unit such as a speaker (not shown) is also provided.

[0020] Fig. 2 is a cross-sectional view showing a detailed structure of the centrifugal separation unit 100 in Fig. 1. The rotor 10 suspended from the drive unit 130 is housed inside the chamber 101, and an evaporator (not shown) is installed to cover the periphery of the rotor 10. The evaporator is made of copper piping that circulates refrigerant gas, thereby cooling the inside of the chamber 101 to a set temperature.

[0021] The driving unit 130 is configured to include a motor (not shown). When performing centrifugation, a sample is injected into the rotor 10 from the lower shaft 141 side, and the sample introduced into the rotor 10 is moved to a high centrifugal force field (a centrifugation space S described later) by the core 30 described later and separated into a precipitate and a supernatant. The supernatant (waste liquid) is discharged from a sample passage hole in the upper shaft 131.

[0022] The motor has a hollow rotating shaft (upper shaft 131) extending in the vertical direction, and the upper rotor cover 19 is fixed to the lower end of the upper shaft 131 by a nut 132, and the rotor 10 rotates while being suspended from the drive unit 130. A lower shaft 141, which is a rotating shaft, is attached to the lower rotor cover 24 by a nut 142. Through holes (sample passing holes) which are upper and lower passages penetrate the centers of the respective rotating shafts of the upper shaft 131 and the lower shaft 141, and these sample passing holes communicate with sample passing holes formed in the upper rotor cover 19 and the lower rotor cover 24, respectively. When the upper shaft 131 rotates at high speed by the drive of the motor included in the drive unit 130, the rotor 10 attached to the upper shaft 131 rotates at high speed together with the lower shaft 141. The lower shaft 141 which rotates accompanying the rotor 10 is supported by the lower rotation support unit 140. The lower rotation support 140 is fixed to the base 110 at a position where it abuts against the chamber 101 .

[0023] The sample is supplied from the sample tank 171 and flows into the rotor 10 through the lower connecting pipe 172, the liquid sending pump 173, the mass flowmeter 175, the lower rotation support 140, and the lower shaft 141. When the sample is placed in the sample tank 171 and the liquid sending pump 173 is operated to start supplying the sample to the rotor 10 from the lower connecting pipe 172 through the lower shaft 141, the rotor 10 is gradually filled with the sample. When the rotor 10 is filled with the sample, the overflowing liquid passes through the upper shaft 131 and the drive unit 130 and is sent to the upper connecting pipe 182 and discharged into the supernatant recovery tank 181. The injection of the sample into the rotor 10 is adjusted by controlling the liquid sending pump 173 with a control device (not shown).

[0024] The supernatant of the sample separated by centrifugal separation due to the high speed rotation of the rotor 10 passes through the upper shaft 131 and the drive unit 130, flows into the upper connecting pipe 182, passes through the mass flowmeter 185, and is collected in the supernatant collection tank 181. In this embodiment, the sample line is configured so that the sample is injected from the lower side of the rotor 10 and the supernatant is discharged from the upper side, so that the lower connecting pipe 172 serves as the sample supply line and the upper connecting pipe 182 serves as the supernatant discharge line. The lower connecting pipe 172 connects between the sample tank 171 and the lower rotation support unit 140, and a liquid delivery pump 173 and a supply side mass flowmeter 175 are provided in the path. The upper connecting pipe 182 connects between the upper shaft 131 of the drive unit 130 and the supernatant collection tank 181.

[0025] The liquid delivery pump 173 is a sample supplying means that is electrically controlled by the control device to send or stop, and is, for example, a motor-driven fluid pump. For example, an in-line Coriolis mass flowmeter can be used as the mass flowmeter 175, which measures the mass flow rate of the sample flowing through the lower connecting pipe 172 and outputs a signal corresponding to the value to the control device. The mass flowmeter 185 measures the mass flow rate of the sample flowing through the upper connecting pipe 182 and outputs a signal corresponding to the value to the control device. The same measuring device can be used for the mass flowmeter 185 and the mass flowmeter 175, and their outputs are sent to the control device. The piping method of the lower connecting pipe 172 and the upper connecting pipe 182 that constitute the sample line, and the arrangement and connection of the sample tank and the supernatant tank used are arbitrary, and depending on the sample to be centrifuged, the sample may be supplied to the rotor 10 from the upper connecting pipe 182 and waste liquid may be collected from the lower connecting pipe 172.

[0026] FIG. 3 is a longitudinal sectional view of the rotor 10 shown in FIG. 1. The rotor 10 is mainly composed of the rotor body 11, the core body 31, the fins 40, the upper rotor cover 19, and the lower rotor cover 24. A cylindrical core 30 is disposed inside the cylindrical rotor body 11 so as to be coaxial with the rotation axis A1. The core 30 is configured so as to be axially removable from the rotor body 11, and is used to introduce a sample injected inside the rotor body 11 into a high centrifugal field. A female screw portion 12 is formed near the upper opening of the rotor body 11, and a male screw portion 22 is formed near the opening of the upper rotor cover 19. The male screw portion 22 and the female screw portion 12 are screwed together to fix the upper rotor cover 19 to the rotor body 11. An O-ring 13 is interposed between the upper rotor cover 19 and the upper opening of the rotor body 11. Similarly, a female thread 14 is formed near the lower opening of the rotor body 11, and a male thread 28 is formed near the opening of the lower rotor cover 24, and the male thread 28 and the female thread 14 are screwed together to fix the lower rotor cover 24 to the rotor body 11. An O-ring 15 is interposed between the lower rotor cover 24 and the lower opening of the rotor body 11. In this way, the upper and lower sides of the cylindrical rotor body 11 are closed by the rotor covers (19, 20), thereby sealing the gap between the upper rotor cover 19 and the rotor body 11, and the gap between the lower rotor cover 24 and the rotor body 11.

[0027] A cylindrical protrusion 20 that protrudes upward is formed on the rotation axis A1 of the upper rotor cover 19. A male thread 20a is formed on the outer circumferential surface of the protrusion 20, and a flow path 23a that extends axially from the upper surface is formed on the rotation axis A1. The flow path 23a is screwed with a female thread formed on the inner circumferential side of a nut 132 of the upper shaft 131 to define a sample passage that continuously discharges the sample from the rotor 10 to the upper shaft 131. The flow path 23a opens into a recess 20b formed in the upper rotor cover 19, and the lower side of the flow path 23a is connected to four branch paths 23b (only two are visible in the figure) that branch diagonally radially. The branch paths 23b open to a connection between the fitting hole 32 of the core body 31 and the fitting shaft 21.

[0028] The lower rotor cover 24 is formed with a protrusion 25 that protrudes downward and is coaxial with the rotation axis A1. A male thread 25a is formed on the outer circumferential surface of the protrusion 25, and a flow path 27a that extends axially from the lower surface of the protrusion 25 is formed coaxially with the rotation axis A1. The flow path 27a is screwed with a female thread formed on the inner circumferential side of the nut 142 of the lower shaft 141 to define a sample circulation path for continuously injecting a sample from the lower shaft 141 to the rotor 10. The flow path 27a opens into a recess 25b formed in the lower rotor cover 24, and is connected to four branch paths 27b that branch obliquely radially in the upper part of the internal space of the rotor 10. The branch paths 27b open near the connection surface between the fitting hole 35 of the core body 31 and the fitting shaft 26 formed in the lower rotor cover 24.

[0029] The core 30 is a solid member, and is fixed so as not to rotate relative to the rotor body by inserting a pin (not shown) for fixing the core, which is provided on the lower rotor cover 24, into a pin hole 34 in the rotor body. The core 30 forms a separation space S used for centrifugal separation operation in the radially outer part of the internal space of the rotor body 11, and also functions as a partition member for defining a plurality of separation spaces S1 to S6 (reference numerals will be referred to in FIG. 4 described later) partitioned in the circumferential direction. The core 30 in this embodiment is made of synthetic resin, and six fins 40 are attached to a fin mounting groove 37 formed so as to be recessed inward from the outer circumferential surface of the core body 31. The fin mounting groove 37 is formed to have the same size as the core 30 in the direction of the rotation axis A1, and is formed continuously from the upper end to the lower end of the core body in the direction parallel to the rotation axis A1, and has a substantially uniform cross-sectional shape in the direction of the rotation axis A1, except for the vicinity of both the upper and lower ends. The shape of the fin 40 will be described later with reference to FIG. 4 and FIG. 5.

[0030] FIG. 4 is a cross-sectional view of the AA portion of FIG. 3. At this cross-sectional position, the core body 31 and the fins 40 correspond to a top view. In addition, the upper rotor cover 19 corresponds to the outer circumferential side at the AA portion of FIG. 3, but since the cross-sectional shape is the same, for convenience of explanation, the rotor body 11 is described as being located outside the core body 31. The core 30 is composed of a cylindrical core body 31 and a plurality of fins 40 extending radially outward from the core body 31 in a radial direction centered on the rotation axis A1 (central axis). As a result, six separation spaces S (S1 to S6) separated by the six fins 40 are formed inside the rotor body 11, as shown in FIG. 4. The upper surface of the core body 31 is formed with an annular groove portion 23c and six guide grooves 33 extending linearly from the groove portion 23c toward the radially outward direction. The guide grooves 33 are formed by forming the upper surface 31a as a recess having a depth substantially equal to the width of the groove. On the outer circumferential side of groove portion 23c, upper surface 31a of core 30 other than the portion where guide groove 33 is formed is in good contact with the inner wall surface (lower surface) of upper rotor cover 19, so that a long and narrow flow path is formed by the recess of guide groove 33 and the lower surface of upper rotor cover 19. In other words, guide groove 33 serves as a conduit (flow path) for connecting groove portion 23c, which is a doughnut-shaped space, to the vicinity of the upper ends of separation spaces S1 to S6.

[0031] A fitting shaft 21 (see FIG. 3) protruding downward is provided on the lower surface side of the region including the rotation axis of the upper rotor cover 19. A fitting hole 32 that fits with the fitting shaft 21 is provided on the upper side of the core body 31, and the fitting shaft 21 and the fitting hole 32 are fitted together. Although not shown here, six guide grooves 38 similar to the guide groove 33 are formed on the lower end surface of the core body 31. Each guide groove 38 has the same shape as the upper surface 31a of the core body 31, and is connected to the lower ends of the six centrifugal separation spaces S1 to S6. A fitting shaft 26 (see FIG. 3) protruding upward is provided on the upper side of the lower rotor cover 24, and fits into a fitting hole 35 (see FIG. 3) formed on the lower side of the core body 31. In this way, the upper rotor cover 19, the core 30 (core body 31), and the lower rotor cover 24 are fixed so as to be connected, and the rotor 10 is driven as a unit by the drive unit 130.

[0032] As described above, the centrifugation space S defined by the core 30 and the rotor body 11 has the fins 40 provided at equal intervals in the circumferential direction (rotation direction), and the centrifugation space S is divided into a plurality of spaces S1 to S6, thereby suppressing the generation of turbulence in the sample being centrifuged. If the centrifugation space S (S1 to S6) were a continuous space, a so-called doughnut-shaped space, there would be a high risk that the sample would rotate in the circumferential direction within the centrifugation space S and convect due to acceleration or deceleration during acceleration or deceleration of the rotor 10. To prevent this convection, the fins 40 are provided at equal intervals in the circumferential direction, and the centrifugation space is divided into six spaces S1 to S6.

[0033] FIG. 4B shows a state where either the fin 40 or the fin 50 is attached to the core body 31. Fin mounting grooves 37 are formed at six locations in the circumferential direction of the core body 31. The fin mounting grooves 37 are grooves recessed from the outer peripheral surface of the core body 31 in the direction of the rotation axis A1, and are formed continuously from the upper part to the lower part of the core body 31 parallel to the rotation axis A1. The fin mounting groove 37 has two side wall surfaces 37b, 37c whose wall surfaces are formed parallel or nearly parallel. A bottom surface 37d is formed on the side of the two side wall surfaces 37b, 37c close to the rotation axis A1, and the side opposite to the bottom surface 37d is the opening surface 37a of the fin mounting groove 37. The fin mounting groove 37 is formed at the middle position between the radial outer openings of two adjacent guide grooves 33 when viewed in the circumferential direction centered on the rotation axis A1. Therefore, the number of guide grooves 33 (=6) and the number of fin mounting grooves 37 (=6) are the same. Either the fin 40 or the fin 50 is attached to the fin attachment groove 37. The fin 40 realizes a core of the same type as a conventional core, and when the fin 40 is attached to the core body 31, the external shape is the same as a conventional core manufactured by integral molding with the core body. The configuration of this centrifuge other than the core 30 is the same as that of the centrifuge 1 having a conventional core integrated with the fins. Therefore, the present invention can be realized by changing the core 30 from the integrated core (not shown) of the conventional centrifuge 1.

[0034] The core body 31 is manufactured by integral molding of synthetic resin, for example, modified polyphenylene ether (m-PPE). The fin 40 is also configured by integral molding of synthetic resin such as modified polyphenylene ether. The fin 40 has two parts, an attachment part 41 and a protruding part 42. The attachment part 41 is a part that is fitted into the fin mounting groove 37 of the core body 31, and has a width that is almost the same as the circumferential width of the fin mounting groove 37 (however, the width is slightly smaller so that the fin can be inserted into the fin mounting groove 37). The protruding part 42 is a part that protrudes radially outward from the cylindrical outer edge of the core body 31. The cross-sectional shape of the protruding part 42 is a tapered shape in which the circumferential thickness decreases from the attachment part 41 toward the tip (radially outward) from the tip.

[0035] The fin 50 is a fin newly prepared in the embodiment of the present invention, and is formed of an attachment portion 51 and a protruding portion 52, similar to the fin 40. The fin 50 can also be manufactured by integral molding of a synthetic resin such as modified polyphenylene ether. The shape of the attachment portion 51 is the same as the shape of the attachment portion 41 of the fin 40, and is a shape that is inserted entirely into the recess of the fin mounting groove 37. The protruding portion 52 is a portion that protrudes radially outward from the outer peripheral surface of the core body 31 and the opening surface 37a of the fin mounting groove 37, and is shaped like a part of a cylindrical centrifugal separation space cut out approximately parallel to the rotation axis A1 by an angle of about 20 degrees. The length of the protruding portion 52 in the rotation direction (circumferential direction) is formed to be larger than the width of the fin mounting groove 37, and the area of ​​the outer peripheral surface of the fin 50 is sufficiently larger than the area of ​​the opening surface 37a of the fin mounting groove 37.

[0036] Since the protrusion 52 occupies a part of the centrifugal separation space, the volume of the available centrifugal separation space S11 to S16 can be reduced. When attaching the fins 50, all the attached fins 40 are removed from the core body 31, and the six fins 50 are attached to the removed fin attachment grooves 37. Here, it is important to attach fins of the same size (fins 40 or 50) rather than attaching different fins to the core body 31 in a mixed manner. This is to make the volumes of the six centrifugal separation spaces defined by the fins 40 or 50 equal. The fins 40 or 50 only need to have the attachment parts 41, 51 fitted into the fin attachment grooves 37, and are not fixed using a separate fixing member such as a screw. Here, the fins 40, 50 are formed so that when the fins 40, 50 are attached to the fin attachment grooves 37, there is as little gap as possible between the attachment parts 41, 51 and the fin attachment grooves 37, and there is a very small gap that allows the user to manually attach and remove the fins.

[0037] The fins 40 or 50 are attached and removed when the rotor 10 is disassembled and the core 30 is separated from the rotor body 11. No jigs or tools are required to attach and remove the fins 40, 50 to and from the core body 31. Therefore, the user can easily attach and remove the fins 40, 50 when disassembling and cleaning the rotor 10. Also, the fact that the fins 40 and 50 are detachable is advantageous when cleaning the rotor 10.

[0038] FIG. 4(C) is a diagram showing a state where the fin 50 is attached instead of the fin 40, and corresponds to FIG. 4(A). The core body 31 used in FIGS. 4(A) and (C) is the same. The outer peripheral surface of the fin 50 is formed as an arc surface having an outer diameter almost equal to the size (inner diameter) of the inner circumference of the rotor body 11, and contacts the inner peripheral wall surface of the rotor body 11 so as to face it. As can be seen from FIG. 4(C), the volume of each of the centrifugal separation spaces S11 to S16 is significantly reduced to less than half of the centrifugal separation spaces S1 to S6 in FIG. 4(A). The circumferential size of the protruding portion 52 of the fin 50 can be set arbitrarily, and the volume of each of the centrifugal separation spaces S11 to S16 is determined by the size.

[0039] After either the fins 40 or fins 50 are attached, the core body 31 is inserted into the rotor body 11 from the lower or upper opening. Therefore, the shape of the fins 50 is determined to allow this insertion, that is, to have a size such that the outer circumferential surface of the fins 50 slides on the inner circumferential wall surface of the rotor body 11. The adoption of such an assembly method is the same as the conventional disassembly and assembly method of the rotor 10, and the only difference is that the core 30 can be further disassembled into the core body 31 and the fins 40 or 50, making it easy for users to handle.

[0040] As described above, in this embodiment, by mounting the fin 50 instead of the fin 40, it was possible to form the centrifugal separation spaces S11 to S16 having a small volume less than half that of the centrifugal separation spaces S1 to S6 in Fig. 4(A). Although the circumferential length of the centrifugal separation spaces S11 to S16 is smaller than that of the centrifugal separation spaces S1 to S6, each of the centrifugal separation spaces S11 to S16 is formed outside the guide groove 33 formed radially in the radial direction, and the distance from the rotation axis A1 of the inner peripheral wall and the outer peripheral wall of the centrifugal separation spaces S11 to S16 is the same as that of the normal centrifugal separation spaces S1 to S6 shown in Fig. 4(A). In other words, by using the fin 50 in which the circumferential length of the protruding portion of the fin 40 is changed, the flow path cross-sectional area can be changed without changing the radial dimension of the separation spaces S11 to S16 (centrifugal field). Therefore, since the centrifugal acceleration applied to the sample is the same in the centrifugal separation operation using the fins 40 and in the centrifugal separation space using the fins 50 at the same rotation speed, it is possible to quickly optimize the operating conditions using a small amount of sample without changing the separation conditions according to the sample volume. The side wall of the fins 50 as viewed in the circumferential direction is formed so that the angle θ1 occupied by the inner circumferential side is smaller than the angle θ2 occupied by the outer circumferential side (55).

[0041] FIG. 5(A) is a top view of the core body 31 of the present embodiment with the fin 50 of the present embodiment attached thereto, and FIG. 5(B) is a partial view of FIG. 5(A). The end faces 54a and 54b of the fin 50, which are side walls when viewed in the circumferential direction, have an angle θ1 of 15 degrees on the inner circumferential direction, whereas the angle θ2 of 20 degrees on the outer circumferential direction. That is, the centrifugation spaces S11 to S16 are formed such that the distance D1 on the inner circumferential direction is smaller than the distance D2 on the outer circumferential direction, and the centrifugation spaces are formed to expand in a horizontal plane from the inside to the outside. This expanding shape of the centrifugation spaces S11 to S16 is advantageous in separating most samples. The sizes of D1 and D2 can be selected arbitrarily, and although it is preferable if D1≦D2, it may be more appropriate to form D1>D2 depending on the sample to be centrifuged.

[0042] The fin 50 shown in Fig. 5(B) is a fin for small capacity. The shape of the outer peripheral surface 55 of the fin 50 is similar to the shape of the inner peripheral wall of the rotor body 11. The inner peripheral surface of the fin 50 is formed with an inner peripheral surface 53a on one side in the rotation direction and an inner peripheral surface 53b on the other side with the protrusion 52 in between, and the inner peripheral surfaces 53a and 53d are formed in the same shape as the outer peripheral surface of the core body 31, i.e., in the form of an arcuate surface, so that they can be in good contact with the outer peripheral surface of the core body 31. The end faces 54a and 54b of the fin 50 are not shaped along a vertical plane passing through the rotation axis A1, but are given a predetermined angle θ (see Fig. 5(A)) such that the outer peripheral side widens.

[0043] 5(C) is a fin for medium capacity, with a smaller capacity than the standard fin 40, but a larger capacity than the small-capacity fin 50. The shape of the fin 60 is similar to that of the fin 50, and is formed from an attachment portion 61 and a protruding portion 62, with the only difference being the circumferential length of the protruding portion 62 compared to the protruding portion 52. The shape of the outer peripheral surface 65 of the fin 60 is similar to the shape of the inner peripheral wall of the rotor body 11. The inner peripheral surfaces 63a, 63d of the fin 60 are formed to be the same shape as the outer peripheral surface of the core body 31 so as to be able to closely contact the outer peripheral surface of the core body 31 well.

[0044] As described above, the fins 50, 60 are formed to include the mounting portions 51, 61 having a shape corresponding to the fin mounting groove 37 and the protruding portions 52, 62 protruding radially outward from the fin mounting groove 37, and the protruding portions 52, 62 are formed to extend in both circumferential directions of the rotor 10 beyond the range in which the fin mounting groove 37 is formed, thereby making it possible to change the volume of the centrifugal separation space S between the core body 31 and the rotor body 11. Note that, in this embodiment, the examples of the two fins 50, 60 in Figs. 5(B) and (C) have been described, but it is also possible to define a centrifugal separation space smaller or larger than that of the fin 50 by further extending or shortening the circumferential direction of the protruding portion 52 of the fin 50 shown in Fig. 5(B).

[0045] FIG. 6(A) is a perspective view showing the overall shape of the standard fin 40 shown in FIG. 4(A). The fin 40 has a length corresponding to the core body 31 in the direction of the rotation axis A1 (vertical direction), and is formed with approximately the same cross-sectional shape from the upper end to the lower end except for both the upper and lower ends. The upper end surface 41a of the mounting portion 41 is flat like the upper surface 31a of the core body 31 (see FIG. 4), and is formed with a surface perpendicular to the rotation axis A1. The upper end of the protruding portion 42 is formed with a curved surface 42a that descends toward the radially outward side. In other words, the curved surface 42a is formed with a shape that follows the inner wall surface of the upper rotor cover 19. The fin 40 has a vertically symmetrical shape, and can be attached with either end on the upper side of the core body 31. Therefore, although not shown in the figure, the lower end surface of the mounting portion 41 and the lower end surface of the protruding portion 42 are formed with a vertically symmetrical shape with respect to the upper end surface 41a and the curved surface 42a.

[0046] FIG. 6(B) is a perspective view showing the overall shape of the fin 50 for forming the small-capacity centrifugal separation spaces S11 to S16 shown in FIG. 4(C). The length of the fin 50 in the direction of the rotation axis A1 (vertical direction) is the same as that of the fin 50, and is equal to the vertical length of the core body 31. The cross-sectional shape of the fin 50 perpendicular to the rotation axis A1 is almost the same from the upper end to the lower end, except for both the upper and lower ends. The upper end surface 51a of the mounting part 51 is flat like the upper surface 31a of the core body 31 (see FIG. 4), and is formed by a surface perpendicular to the rotation axis A1. The upper end 52a of the protrusion 52 is formed by a curved surface 52a that descends toward the outside in the radial direction so as to follow the inner wall surface of the upper rotor cover 19. The fin 50 has a vertically symmetrical shape, and can be attached with either end on the upper side of the core body 31. Although not shown in the figure, the lower end surface of mounting portion 51 and the lower end surface of protruding portion 52 are formed in a shape that is vertically symmetrical with respect to upper end surface 51a and curved surface 52a.

[0047] FIG. 6(C) is a horizontal cross-sectional view for explaining the state when the rotor 10 is rotated at high speed with the fins 50 for small capacity. At the start of rotation of the centrifugation operation, a density gradient layer is formed in the centrifugation spaces S11 to S16, and the sample to be separated is further injected while the rotor 10 is rotating, so that the centrifugation spaces S11 to S16 are finally filled with the sample. When the rotor 10 is rotated at high speed, a strong centrifugal load is applied to the rotor body 11, the core body 31, and the fins 50. At this time, the components of the sample with a high density are separated to the outer periphery side of the centrifugation spaces S11 to S16, and the components with a low density move to the inner periphery side of the centrifugation spaces S11 to S16. During the centrifugation of such a sample, whether the fins 50 move outward or inward is determined depending on the relative relationship with the density of the sample filled in the centrifugation spaces S11 to S16. In other words, when the rotor 10 rotates, the fins 50 will move (move) to either the inner side or the outer side depending on the relationship between the density of the sample supplied into the rotor 10 and the density of the fins 50.

[0048] In this embodiment, the fin 50 is formed so as to have a density lighter than the density of the density gradient liquid (usually a density of about 1 to 1.22) and the density of the maximum component contained in the sample. By setting the density of the fin 50 to a certain range (here, specific gravity less than 1.20), a relative force as shown by arrows 57a to 57b is applied from the sample to the protruding portion 52 of the fin 50 during high-speed rotation of the rotor 10, and the fin 50 is pressed against the inner core body 31. In addition, during high-speed rotation of the rotor 10, the rotor body 11 is slightly expanded outward due to a strong centrifugal force, and a gap 56 is formed between the protruding portion 52 of the fin 50 and the inner peripheral surface of the rotor body 11, but this embodiment allows this state to occur. When a centrifugal load as shown by arrows 57a to 57b is applied, the outer peripheral surface of the core body 31 and the inner peripheral surfaces 53a and 53b of the protruding portion 52 are in close contact with each other, so that the sample can be prevented from entering the gap between the fin mounting groove 37 and the mounting portion 51. If a gap 56 is created while the rotor 10 is rotating at high speed, the components to be separated may get into the gap. Note that the actual gap 56 in Figure 6(C) is usually difficult to confirm with the naked eye, so for the sake of understanding the invention, it is shown diagrammatically as if the radial gap were larger.

[0049] As described above, in this embodiment, by using fins 40 and 50 with different circumferential widths attached to the core body 31, the flow passage cross-sectional area can be changed without changing the radial dimensions of the centrifugal separation spaces (centrifugal fields) S1 to S6 or S11 to S16. Therefore, a test run can be performed using a small amount of sample prepared to determine the operating conditions, so that the optimization work of the centrifugal operation conditions can be performed quickly. Furthermore, since the operating conditions can be determined using a small amount of sample, the amount of sample to be discarded after the test run can be reduced. In addition, by preparing multiple fins with different circumferential widths of the protruding parts, a rotor 10 having multiple stages of centrifugal separation spaces can be realized.

[0050] Next, modified examples of the present invention will be described with reference to Fig. 7. Fig. 7 shows a fin 70 for small capacity according to a first modified example of this embodiment, and (A) is a horizontal cross-sectional view. As described above, the density (unit: g / cm 3) is made to be within a predetermined range compared to the density of the density gradient liquid and the sample, so that during centrifugation, the fins 50 can operate to closely adhere to the inner core body 31 as shown by the arrows 57a to 57c in Fig. 6(C). In order to ensure this operation, it may be important to make the specific gravity of the entire fin 50 smaller than the density inherent in the constituent material. The fin 70 in Fig. 7 is the same as the fins 40, 50, and 60 in terms of being manufactured by integrally molding a synthetic resin, but a cavity 76 is formed in a part of the internal space of the fin 70 so that the specific gravity of the fin 70 in a state of being attached to the core body 31 is smaller than that of the fin 50. The external shape of the fin 70, that is, the size of the outer peripheral surface 75, the thickness T of the protruding portion 72, the sizes of the inner peripheral surfaces 73a and 73b, the positions of the end surfaces 74a and 74b, and the inclination angle with respect to the tangent of the end surfaces 74a and 74b are the same as those of the fin 50.

[0051] The cavity 76 of the fin 70 is formed so as to be in contact with the outer surface of the reference fin 50. Here, the cavity 76 extends radially outward from the inner peripheral surface of the mounting portion 71, and the bottom 76b as seen from the opening 76a is located inside the protruding portion 72. Since the cavity 76 is formed to reach not only the mounting portion 71 but also the protruding portion 72 in this way, the fin 70 can be made lighter by the amount of the material of the portion occupied by the cavity 76, and the overall mass can be reduced with respect to the volume occupied by the fin 70, that is, the specific gravity can be reduced. The cavity 76 is formed so as to have a width W2 (where W2 < W1) with respect to the width W1 in the circumferential direction of the mounting portion 71. Since the opening 76a of the cavity 76 is closed by the fin mounting groove 37 of the core body 31, it is possible to prevent the sample from flowing into the inside thereof. Also, since the fin 70 is biased radially inward as shown in Fig. 6(C) during the rotation of the rotor 10, it is possible to prevent the possibility of the sample flowing into the cavity 76.

[0052] 7B is a perspective view showing the entire fin 70. The cavity 76 is continuous in the axial direction, but is not formed near both the upper and lower ends, and is not formed near the mounting portion upper surface 71a or the mounting portion lower surface 71b. Similarly, no cavity 76 is formed near the protruding portion upper surface 72a or the protruding portion upper surface 72b. Therefore, when the fin 70 is attached to the core body 31, the cavity 76 is not exposed to the outside. Such a cavity 76 can be easily formed by injection molding the fin 70.

[0053] FIG. 8 is a diagram showing a small-capacity fin 80 according to a second modified example of this embodiment, and (A) is a horizontal cross-sectional view. The fin 80 is an integrally molded product of synthetic resin, and a cavity 86 is formed inside. The cavity 86 is formed inside the protruding portion 82 during injection molding so that air and liquid cannot enter or exit from the outside. The cavity 86 is not disposed inside the mounting portion 81. The cavity 86 can be manufactured using a known synthetic resin blow molding technique, and is molded so that the thickness t of the cavity 86 and the outer peripheral surface 85, the thickness t of the cavity 86 and the end faces 84a, 84b, and the thickness t of the cavity 86 and the inner peripheral surfaces 83a, 83b are almost constant. Since the mounting portion 82 is formed as a solid body rather than a hollow body, the center of gravity of the fin 80 can be formed closer to the rotation axis A1 than the fin 70 shown in FIG. 7, which is advantageous in centrifugal separation operation. In the fin 80 of this modified example, the hollow portion 86 is not exposed to the outside, so there is no need to be aware of the existence of the hollow portion 86 when removing and cleaning the fin 80, and it can be easily cleaned in the same way as the fin 50.

[0054] 8(B) is a perspective view showing the entire fin 80. The cavity 86 has a shape that continues from near the upper end to near the lower end in the direction of the rotation axis A1, but since wall surfaces are formed on the protruding portion upper surface 82a and the protruding portion lower surface 82b and the cavity 86 is closed, the air within the cavity 86 does not communicate with the outside.

[0055] As described above, according to this embodiment, the flow path area can be changed by simply replacing the vane parts (fins 50, 60, 70) without changing the radial dimension of the main body part (core body 31) of the core 30. In the embodiment of the present invention, the fins are made of synthetic resin, but they may be made of metal by integral molding, not just synthetic resin. In a continuous centrifuge, steam sterilization may be used in the cleaning and disinfecting process of the rotor 10 depending on the sample to be separated. In steam sterilization, high-temperature steam is passed through the rotor 10, so it may be preferable to manufacture the rotor 10 from metal such as titanium rather than synthetic resin. In that case, it is preferable to manufacture both the fins 50, 60, 70 and the core body 31 from metal. EXAMPLES

[0056] Next, a fin 50A according to a second embodiment of the present invention will be described with reference to FIG. 9. FIG. 9 is a vertical cross-sectional view of a rotor 10A according to a second embodiment of the present invention. The rotor 10A has a rotor body 11, an upper rotor cover 19, and a lower rotor cover 24, and a core 30A is housed therein. The core 30A is composed of a core main body 31A and a fin 50A. The fin mounting grooves 37, 37A are continuously formed from the upper end to the lower end in the direction of the rotation axis A1 (vertical direction) on the outer circumferential surface of the core main body 31. Here, the shape of the fin mounting groove 37 is not the same in the direction of the rotation axis A1, and the groove depth (= the distance from the outer circumferential edge of the core main body to the inner circumferential surface (bottom surface) of the fin mounting groove 37) 38b is gradually deepened in a predetermined range (part of height H2) on the lower side of the core main body 30A compared to the fin mounting groove 37 of the first embodiment. The upper rotor cover 19, the rotor body 11, and the lower rotor cover 24 are the same as those in the first embodiment shown in FIG. 3, and the same parts are used. In the range of the upper side H1 of the core body 31A, the groove depth 38a of the fin mounting groove 37 (= the groove depth of the fin mounting groove 37 from the outer periphery of the core body) is constant. On the other hand, in a predetermined range of the lower side H2 of the core body 30A (this range is called the "tapered portion" in this specification), the groove depth 38b of the fin mounting groove 37A is formed so as to gradually increase from the upper end to the lower end of the tapered portion. The shape of the fin 50A to be mounted on the core body 31A is formed to match the shapes of the fin mounting grooves 37, 37A.

[0057] The cross-sectional shape of the fin 50A perpendicular to the rotation axis A1 at the portion indicated by the upper height H1 is the same as the cross-sectional shape of the fin 50 shown in FIG. 6(B). However, in the cross-sectional shape of the tapered portion indicated by the lower height H2, although the shape of the protrusion 52 is the same, the shape of the attachment portion 51A is elongated in the direction perpendicular to the rotation axis A1 according to the groove depth 38b of the fin mounting groove 37A. By forming the fin mounting groove 37A in a tapered shape and forming the fin 50A in a corresponding shape, when the core body 31 is provided in the rotor body 11 and the lower rotor cover 24 is removed, the fin 50A can be attached by moving the fin 50A upward in the direction of the rotation axis A1 from the lower side relative to the fin mounting groove 37. At this time, the upper end of the fin 50A abuts against the upper rotor cover 19, so that the position of the fin 50A in the vertical direction relative to the core body 31 is determined. Similarly, when removing the fins 50A attached to the core body 31, the fins 50A can be removed by pulling them downward from the core body 31. In the second embodiment, it is particularly easy to attach the fins 50A to the core body 31 from below, or to remove the fins 50A downward from the core body 31. In particular, when removing the fins 50A, not only can the rotor 10 be removed in a completely disassembled state, but the six fins 50A can also be removed in a partially disassembled state in which only the lower rotor cover 24 of the removed rotor 10 has been removed.

[0058] Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and various modifications are possible within the scope of the present invention. For example, the fins 40, 50, 60, 70, and 80 may be fixed to the core body 31 with screws. Furthermore, if the center of gravity of the rotor 10 is located on the rotation axis, the fins may be shaped so that the centrifugal separation space can be reduced from six sections to three or two sections. Furthermore, two types of fins 40, 50, 60, 70, and 80 may be used in combination as necessary, but in this case, it is important to arrange them rotationally symmetrically so that the center of gravity of the various fins attached to the rotor body 11 is located on the rotation axis. [Explanation of symbols]

[0059] 1...centrifuge, 10, 10A...rotor, 11...rotor body, 12, 14...female thread portion, 13, 15...O-ring, 19...upper rotor cover, 20...projection portion, 20a...male thread portion, 20b...recess, 21...engagement shaft, 22...male thread portion, 23a...flow path, 23b...branch path, 23c...groove portion, 24...lower rotor cover, 25...projection portion, 25a...male thread portion, 25b...recess, 26...engagement shaft, 27a...flow path, 27b...branch path, 28...male thread portion, 30, 30A...core, 31, 31A...core body, 31a...(core body) upper surface, 32...engagement hole, 33...guide groove, 34...pin hole, 3 5...fitting hole, 37, 37A...fin mounting groove, 37a...opening surface, 37b, 37c...side wall surface, 37d...bottom surface, 38...guide groove, 38...depth (of fin mounting groove), 40...fin, 41...mounting portion, 41a...upper end surface (of mounting portion), 42...protruding portion, 42a...curved surface, 50, 50A...fin, 51...mounting portion, 51a...upper end surface of mounting portion, 52...protruding portion, 52a...upper end portion, 53a, 53b...inner peripheral surface, 54a, 54b...end surface, 55...outer peripheral surface, 56...gap, 57a to 57c...centrifugal load, 60...fin, 61...mounting portion, 62...protruding portion, 63a, 63b...inner peripheral surface, 64a, 64b ...end surface, 65...outer peripheral surface, 70...fin, 71...mounting portion, 71a...upper end surface of mounting portion, 71b...lower end surface of mounting portion, 72...protrusion, 72a...upper surface of protrusion, 73a, 73b...inner peripheral surface, 74a, 74b...end surface, 75...outer peripheral surface, 76...cavity, 76a...opening, 76b...bottom, 80...fin, 81...mounting portion, 82...protrusion, 82a...upper surface of protrusion, 82b...lower surface of protrusion, 84a, 84b...end surface, 85...outer peripheral surface, 86...cavity, 100...centrifugal separation portion, 101...chamber, 110...base, 111...bolt, 112...bolt, 130...drive portion, 131...upper shaft, 1 32...nut, 140...lower rotation support part, 140a...nut, 141...lower shaft, 142...nut, 160...lift, 161...arm, 171...sample tank, 172...lower connecting pipe, 173...liquid transfer pump, 175...mass flow meter, 181...supernatant recovery tank, 182...upper connecting pipe, 185...mass flow meter, 200...control device part, 205...operation panel, 250...piping group, 311...rotor body, 331...core body, 337...fin mounting groove, 340...fin, 341...fin base, 342...fin tip, 345...movable range, A1...rotation axis, S,S1~S6...separation space (normal), S11~S16...separation space (reduced),

Claims

1. A rotor for a centrifuge includes a core having a columnar core body and a plurality of fins attached to the core body so as to protrude radially from an outer circumferential surface of the core body, and a cylindrical rotor body surrounding the core, and the rotor is configured such that a sample is caused to flow between both ends in the direction of the rotation axis of the core body and the rotor body, the rotor rotating around the rotation axis, The fin is detachable from the core body, A plurality of types of fins are prepared, each having a different circumferential width of a portion protruding radially outward from an outer circumferential surface of the core body, A rotor characterized in that the volume of the centrifugal separation space defined between the core body and the rotor body can be changed by selecting one of a plurality of types of fins and attaching it to the core body.

2. The core body is cylindrical, and a plurality of fin mounting grooves are formed at equal intervals in the circumferential direction on the outer circumferential surface of the core body, The fin mounting groove is formed continuously from the upper end to the lower end of the core body in a direction parallel to the rotation axis of the rotor, The fin is formed by an attachment portion having a shape corresponding to the fin mounting groove and a protrusion protruding radially outward beyond an opening surface of the fin mounting groove, 2. The rotor according to claim 1, wherein a circumferential width of the protrusion is greater than a width of the fin mounting groove.

3. The rotor according to claim 2, characterized in that the protrusion is formed having an inner circumferential surface that contacts the outer circumferential surface of the core body and an outer circumferential surface that contacts the inner circumferential surface of the rotor body, and the area of ​​the outer circumferential surface of each of the fins is larger than the opening area of ​​the fin mounting groove.

4. A sample to be centrifuged is injected into the rotor body from one side in the direction of the rotation axis while the rotor is rotating, and discharged from the other side; 4. The rotor according to claim 3, wherein the fins and the core body are removable from the rotor body when the rotor is disassembled.

5. 2. The rotor according to claim 1, wherein a radial distance between the inside of the rotor body and the space (flow passage) between the core and the rotor body is constant regardless of the selection of the fin.

6. 5. The rotor according to claim 4, wherein the core body and the fins are made of synthetic resin or metal, and the specific gravity of the fins is configured to be smaller than the specific gravity of the core body.

7. The density of the fin is 1.2 g / cm ３ is less than 7. The rotor according to claim 6, wherein when the sample is centrifuged while being flowed through the rotor, the fins move in a direction approaching the rotation axis due to a density difference between the fins and the sample.

8. A cylindrical rotor for separating a sample, and a centrifuge chamber in which the rotor is housed; a drive means for rotating the rotor; and a sample line for continuously supplying and discharging a sample to and from the rotor while the rotor is rotating; The rotor is a centrifuge including a cylindrical rotor body, a core body disposed in the rotor body to form a path for the sample, and a plurality of fins detachably attached to the core body to separate the sample and to divide the inside of the rotor body into a plurality of spaces, The core body is formed with a plurality of fin mounting grooves for mounting the fins, The fin is formed to include an attachment portion having a shape corresponding to the fin mounting groove and a protrusion protruding radially outward from the fin mounting groove, a first fin having a protruding portion that fits within a range in which the fin mounting groove is formed as viewed in a circumferential direction, and a second fin having a protruding portion that extends in a circumferential direction of the rotor from within a range in which the fin mounting groove is formed, A centrifuge characterized in that the volume of the centrifugal separation space between the core body and the rotor body is switched by attaching either the first fin or the second fin to the core body.

9. 9. The centrifuge according to claim 8, wherein the protruding portion of the second fin has an outer surface which has an arcuate surface having an outer diameter approximately equal to the inner diameter of the rotor body, the inner surface of the protruding portion is formed by an arcuate surface which contacts the outer surface of the core body, and the density of the second fin is configured to be smaller than the density of the core body.

10. 8. A centrifuge comprising: the rotor according to claim 1; a centrifuge chamber in which the rotor is housed; a drive unit that drives the rotor; and a sample line that continuously supplies and discharges a sample to and from the rotor while the rotor is rotating.

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