JPH0536104B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a rotor for a centrifuge.

[Background of the Invention] A conventional centrifuge is illustrated in FIGS. 4 and 5. FIG. 4 is a schematic structural diagram of the entire general drive system, FIG. 5A is a sectional view of a rotor for a conventional centrifugal separator, and FIG. In Fig. 4, 1 is the rotor body, 2 is the rotor core,
3 is a shaft fixing nut, 4 and 5 are hollow upper and lower shafts, 6 is an upper plate, 7 is a lower plate, 8 is a bearing, 9 is a drive housing, 10 is a drive stator, and 11 is a drive rotor. It is. 12 is a fixed seal, 13 is a fixed seal holding portion, 14 is a pipeline through which the sample enters and exits as shown by the arrow, and 15 is the outer diameter portion of the core. The rotor body 1 is disposed vertically in the axial center direction, is fixed at the top and bottom to an upper shaft 4 and a lower shaft 5, and is rotationally driven by a drive unit connected to the upper shaft 4. The ends of both the upper and lower shafts 4 and 5 are in contact with fixed seals 12 for loading and unloading the sample.

In FIG. 5, reference numeral 17 denotes an inner diameter portion of the rotor, and 18 denotes a cover, which is connected to both end surfaces of the rotor body 1 in the vertical direction via a liquid sealing mechanism. 19 is a cover liquid flow hole, 21 is a liquid flow path, and 23 is a sector. At the upper and lower ends of the rotor core 2, a core outer diameter portion 1 is provided.
A liquid flow path 21 is provided which leads to 5, and during centrifugation, one side serves as a sample introduction path and the other serves as a flow path for discharging the supernatant after separation. In such a conventional rotor and centrifugal separator, heat is generated in the stationary seal 12 and the bearing 8 during centrifugation while rotating at high speed. The higher the rotational speed and the lower the sample flow rate, the higher the exothermic temperature becomes. Generally, the smaller the particles of the sample to be separated, the higher the rotational speed or the lower the sample flow rate, which may cause the sample to lose its activity or damage the stationary seal 12 or bearing 8 due to the heat generated. Sometimes. Furthermore, since the structure of the rotor body 1 is such that the sample enters the annular cavity and comes out through the annular cavity, if the sample centrifugation conditions are not sufficient, the particles separated in the rotor body 1 will be transferred to the supernatant. Sometimes it gets mixed in and is discharged.

[Purpose of the invention]

The present invention was made in view of the above situation, and an object of the present invention is to provide a rotor for a centrifuge that can prevent damage to the centrifuge and separate small sample particles.

[Summary of the invention]

A rotor for a centrifugal separator according to the present invention includes a cylindrical rotor body, and a cover liquid circulation hole in the axial center direction, which is connected to the connecting portions of both vertical end surfaces of the rotor body through a liquid sealing mechanism, and has a cover liquid flow hole in the rotor body. a cover having a liquid flow passage formed between end faces of the rotor core disposed in the rotor body, and an annular cavity connected to the cover liquid flow hole via the liquid flow passage between the inner periphery of the rotor body; Blade-like sectors that divide the annular cavity into a plurality of parts in the circumferential direction are provided protruding from the outer periphery and are fixed to the rotor core built into the rotor body and to the upper and lower covers, respectively, and the sample to be separated is circulated inside and driven. A hollow upper and lower shaft rotatably driven by the rotor core is provided, and a check valve part that is opened in the axial direction of the axial center of the rotor core and that prevents liquid from flowing upward is provided at the lower end part. It has a through hole. That is, through holes are provided in the vertical direction of the axis of the rotor core through which liquid can flow only from above, thereby allowing cooling fluid to flow through and cool the rotor core.

[Embodiments of the invention]

The rotor for a centrifugal separator according to the present invention will be described below with reference to FIGS. 1 and 2, using embodiments and omitting the explanation of the structure of the same parts, in which the same parts as the conventional ones are denoted by the same reference numerals. 1st
Figure A is a longitudinal cross-sectional view of the rotor, B is a cross-sectional view taken along the - arrow in A, and Figure 2 is a perspective view of the rotor core shown in Figure 1. In the figure, a through hole 24 is opened in the axial direction of the rotor core 2, a check valve part 25 is provided at the lower end of the through hole 24, and a spherical float 26 is provided in the check valve part 25. In the case of flow from below to above, the check valve is formed such that the spherical float 26 comes into contact with the check valve tapered portion 29 to prevent the flow of liquid. The spherical float 26 is hollow and is formed to float lighter than the liquid, and is pushed away when liquid flows in from above, allowing the liquid to flow.
In addition, a lower cover 1 is attached to the lower end of the rotor core 2.
A plurality of liquid flow passages 28 are formed on the outer circumference in contact with the inner circumference of the lower cover 18 and communicate with the lower side of the check valve section 25 and the lower cover liquid circulation hole 19. A core lower flange 27 is provided. An annular cavity partitioned by sectors 23 formed between the inner periphery of the rotor body 1 and the outer periphery of the rotor core 2 is formed in the upper surface of the core lower flange 27 .

FIG. 3 is an explanatory diagram of the centrifugation process, and A shows the sample 16 from below as indicated by arrow D with the rotor stopped.
The sample 16 is injected into the annular cavity inside the rotor body 1 by injecting the low density liquid 20 and the high density liquid 22 necessary for separation through the liquid flow passage 28 that communicates from the lower side of the rotor core 2 to the rotor inner diameter part 17 in that order. . At this time, the spherical float 26 of the check valve portion 25 comes into close contact with the check valve tapered portion 29, and liquid is prevented from entering into the through hole 24. Furthermore, the air within the rotor body 1 is exhausted from the upper end as indicated by arrow E.

After the liquid is injected, the ends of the upper and lower cover liquid flow holes 19 are closed, and the rotor body 1 is driven to rotate. When the rotor body 1 is driven to rotate, the liquid in the rotor body 1, which was arranged in the direction of gravity when it stopped, changes to
They are arranged with their orientation changed in the direction of centrifugal force. This sequence ends at about 3000 γpm. Thereafter, as shown in C, a buffer solution or distilled water that is not harmful to the sample 16 is flowed from above the rotor body 1 as shown by the arrow A, as shown by the arrow A. For buffer solution or distilled water, use through hole 2
4, displacing the spherical float 26 and being discharged as shown by arrow B, and the sample 16 in the annular cavity inside the rotor.
This does not affect the low and high pressure density liquids 20 and 22. In this way, the sample 16 is accelerated to a predetermined rotational speed at which the sample 16 can be separated by being accelerated while operating while cooling the fixed seal 12, the bearing 8, etc. by flowing the buffer solution or distilled water. A centrifugal force acts on the particles inside, and the particles move to the low-high-density liquids 20 and 22 having the same density as themselves, where separation is performed. After that, it decelerates to 3000γpm.

In this 3000 γpm state, the extrusion liquid 30, which has a higher density than the high density liquid 22 injected into the rotor body 1 in A, is injected from below as shown by arrow C in D, and the sample in the rotor body 1 is collected. The extrusion liquid 30 is blocked by the check valve part 25 and does not flow into the through hole 24, but passes through the liquid flow passage 28 and enters the rotor inner diameter part 1.
The extrusion liquid 30 is injected into the outer circumferential side of the annular space in 7, and the extrusion liquid 30 is located on the outer circumferential side of the annular cavity as shown in the figure, and the liquid in the rotor annular cavity is gradually pushed out and discharged from the upper liquid flow passage 21. . The liquid to be separated can be recovered by sequentially fractionating this discharged liquid.

In this way, the centrifuge rotor of this example is
A through hole with a check valve is formed in the axial center of the rotor core to prevent the flow from below upwards, so that the buffer solution or distilled water can flow from above downwards almost unrelated to the sample inside the rotor. Since it can be cooled by flowing, it prevents the temperature of various parts such as fixed seals and bearings from rising, preventing damage to the centrifuge and separating small sample particles. Incidentally, the separation ability of sample particles is determined by centrifugal force x time, and it is effective because temperature rise is prevented for both high-speed rotation and time. In addition, an annular cavity is formed on the upper surface of the core lower flange so that the liquid entering the annular cavity flows from the outer peripheral side of the annular cavity, so the supernatant is separated within the annular cavity and the particles are mixed with the supernatant and discharged. never be done.

〔Effect of the invention〕

As described above, the centrifuge rotor of the present invention has the effect of preventing damage to the centrifuge and separating small sample particles.

[Brief explanation of the drawing]

1 shows an embodiment of the rotor for a centrifuge of the present invention, A is a longitudinal sectional view, B is a sectional view taken along the arrow A, FIG. 2 is a perspective view of the rotor core of FIG. 1, and FIG.
Figures A, B, C, and D are explanatory diagrams of the operation of the rotor in Figure 1 from injection of liquid such as sample to discharge after separation, and Figure 4 is a schematic structure of the entire drive system of a general centrifuge. FIG. 5 shows a conventional rotor for a centrifugal separator, in which A is a longitudinal cross-sectional view and B is a cross-sectional view taken in the direction of the arrow A. 1...Rotor body, 2...Rotor core, 4...Upper shaft, 5...Lower shaft, 18...Cover, 1
9...Cover liquid flow hole, 21, 28...Liquid flow path, 2
3...Sector, 24...Through hole, 25...Check valve part, 2
7... Core lower flange.

Claims (1)

[Scope of Claims] 1. A cylindrical rotor body, and a rotor body that is connected to the connecting portions of both vertical end faces of the rotor body through liquid sealing mechanisms, and has a cover liquid flow hole in the axial center direction, and is disposed within the rotor body. a cover in which a liquid flow passage is formed between the end surfaces of the rotor core;
forming an annular cavity connected to the cover liquid flow hole through the liquid flow passage between the inner periphery of the rotor body;
Further, vane-like sectors that divide the annular cavity into a plurality of parts in the circumferential direction are provided protruding from the outer periphery and are fixed to the rotor core built into the rotor body and to the upper and lower covers, respectively, and the sample to be separated is circulated therein. and a hollow upper and lower shaft rotatably driven by a drive part, the rotor core has a check valve part opened in the axial direction at the center of the shaft and disposed at the lower end part to prevent the flow of liquid upward. A rotor for a centrifuge, characterized in that a through hole is provided. 2 The outer periphery of the annular cavity fits into the inner periphery of the lower cover, and the liquid flow path communicating with the lower side of the check valve and the lower cover liquid circulation hole contacts the inner periphery of the lower cover. The rotor for a centrifugal separator according to claim 1, wherein the rotor is formed on the upper surface of the core lower flange formed on the outer periphery.