JPH0634946B2 - Rotor for centrifuge - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a centrifuge rotor for separating, purifying, extracting, and the like biological materials in the fields of medicine, pharmacy, biochemistry, and genetic engineering.

[Conventional technology]

A material with high specific strength such as titanium alloy, aluminum alloy, and fiber reinforced plastic is used for the rotor for the centrifuge. Fiber-reinforced plastic is new in rotor materials,
Especially carbon fiber reinforced plastic (hereinafter referred to as CFRP)
Has a high specific strength, and has a structure in which fibers are oriented in a plane perpendicular to the rotation axis of the CFRP rotor and strengthens, and has performance comparable to that of a titanium alloy rotor.

There are various types of centrifuge rotors, and one of them is an angle type rotor. This is because the sample hole in which the container for enclosing the sample to be separated is inserted is inclined at an angle of 10 ° or more. In this type of mechanical state, the centrifugal force applied to the rotating container mass against the hole wall surface It is decomposed into a component in the right direction and a component in the parallel direction. The container must be fixed in some way so that the container does not fall out of the sample hole due to this parallel or hole axis force.

As one of the fixing methods, the container has a shape that combines a large diameter opening and a small diameter cylinder, the sample hole has a small radius of rotation and the hole on the upper surface side of the rotor has a large diameter and the hole on the lower surface side with a large rotation radius has a small diameter. There is a method in which both the container and the sample hole are formed in a stepped shape so that the container is not dropped by supporting the stepped surface.

[Problems to be solved by the invention]

However, in the conventional CFRP rotor, the step surface of the container (hereinafter referred to as the container step surface) and the step surface of the sample hole (hereinafter referred to as the hole step surface) are perpendicular to the center axis of the sample hole (hereinafter referred to as the hole axis). there were. However, when the rotor having this shape was rotated, defects such as fiber peeling and peeling occurred on the hole axis stepped surface closest to the rotation axis side in the sample hole.

The present invention seeks to overcome this deficiency.

[Means for solving problems]

The present invention provides an angle type rotor in which a rotor body made of a CFRP laminated body is provided with a sample hole tilted with respect to a rotation axis, and a container for enclosing a sample to be separated is inserted into the sample hole. The structure is characterized in that the gap between the container step surface that receives a force and the hole step surface that is supported by the container step surface provided in the hole is wider toward the rotation axis side when stationary.

The sample hole 1 and the container 2 of the conventional rotor at rest are as shown in FIG. 5 (a). At this time, the hole step surface and the container step surface are in full contact with each other. FIG. 5B shows the relationship between the sample hole 1 and the container 2 during rotation of the rotor. Since the lower part of the container has a larger radius of gyration than the upper part, the relationship between the centrifugal force F _{1 on the} upper part of the container and the centrifugal force F _{2 on the} lower part is F ₂ > F ₁ , and as a result, the container has a counterclockwise moment. Receive M.
In addition, since the force F _{S in the} hole axis direction also acts, the two steps are combined to cause the container step surface to contact the hole step surface, that is, the edge of the container step surface is locally pressed to the hole step surface closest to the rotation axis side. The result is to add P. FIG. 5 (c) is an enlarged view of a portion per one side. This part is a state in which the fibers are discontinuous and independently laminated, and is very weak against compressive force and shearing force. Since the local pressure is applied here, peeling or peeling of the fiber occurs. Therefore, when the rotor is stationary, the container step surface and the hole step surface are tilted so as to widen as they approach the rotation axis side, and the inclination between both steps is gradually reduced as the rotation increases. The local pressure can be prevented if the local pressure is not applied to the near hole step surface. Further, it is most preferable that both step surfaces contact each other when the maximum rotation speed of the rotor is reached. The inclination angle between the step surfaces is determined in consideration of the number of revolutions, the inclination angle of the sample hole, the degree of clearance fit between the sample hole and the container, the material constants of the rotor and the container, and the like.

〔Example〕

 A description will be given below based on examples.

1 (a), (b), FIG. 2, and FIG. 3 are examples of the rotor of the present invention, and are longitudinal sectional views. In FIG. 1 (a), the hole step surface in the sample hole is a surface perpendicular to the hole axis, and the container step surface is inclined with respect to the hole axis step surface (while the rotor is stationary). During rotation, the container step surface and the hole step surface as shown in FIG. FIG. 2 shows a rotor in which the container step surface is made a surface perpendicular to the hole axis and the hole step surface is inclined with respect to the container step surface. In FIG. 3, both the container step surface and the hole step surface are perpendicular to the hole axis, and a washer having a tapered bottom surface is sandwiched therebetween to prevent uneven contact. 1 (a) and (b) to FIG. 3, the maximum rotation speed is 65,000 rpm and the inclination angle of the sample hole 1 is 26.
65,000 at a tilt angle of 0.2 to 5 degrees between the two step surfaces.
It was designed so that both step surfaces contacted each other when the rpm was reached.

FIG. 4 is also a plan view showing a longitudinal sectional view of the embodiment of the rotor of the present invention. The inclination angle of the sample hole 1 is 26 °, and similarly to the embodiment of FIGS. 1 (a) and 1 (b), the container step surface of the container 2 is a plane perpendicular to the hole axis, and the hole step surface is the container step surface. It is inclined with respect to it. The inclination angle between the two step surfaces was 0.2 to 5 ° so that the two step surfaces contacted each other when the maximum rotation speed was reached. One container can contain 40 ml of sample and a total of 12 containers can be inserted into the rotor. Only the rotor body 3 having the sample hole 1 is a CFRP laminated body, and the crown portion 5 having the drive shaft insertion hole axis b into which the drive shaft is inserted is made of an aluminum alloy and both are screw-connected. As the performance of this rotor, the maximum rotation speed is 26,000 rpm, and the maximum centrifugal acceleration applied to the sample is about 100,000 G.

At the time of maximum rotation, all rotors peeled off at the step portion and no peeling occurred.

〔The invention's effect〕

According to the present invention, it is possible to prevent peeling and peeling of the stepped portion in the conventional CFRP angle type rotor, and it is possible to provide a highly reliable rotor.

[Brief description of drawings]

1 (a), (b), FIG. 2 and FIG. 3 are vertical sectional views of an embodiment of the rotor of the present invention, and FIG. 4 is a plan view and a vertical sectional view of the embodiment of the rotor of the present invention. It is shown. FIG. 5A is a vertical cross-sectional view of the rotor while it is stationary, FIG. 5B is a vertical cross-sectional view of the rotor that is rotating, and FIG. 5C is an enlarged cross-sectional view of the step portion that receives the local pressure. Description 1 ...... sample hole code, 2 ...... container 3 ...... rotor body, 4 ...... tapered washer 5 ...... crown, 6 ...... drive shaft insertion holes, 7 ...... fixture, F 1 _...... container upper centrifugal force F 2 _...... vessel lower centrifugal force, M ...... counterclockwise moment F S _...... hole axis direction of the force, P ...... Tsubone圧

Claims (6)

[Claims] 1. An angle type rotor in which a rotor hole made of a carbon fiber reinforced plastic laminate is provided with a sample hole tilted with respect to a rotation axis, and a container for enclosing a sample to be separated is inserted into the sample hole is added to the container. Centrifugal structure characterized in that the gap between the container step surface that receives the force in the axial direction of the hole and the hole step surface that supports the container step surface provided in the hole is made wider toward the rotation axis side when stopped. Separator rotor. 2. The rotor for a centrifuge according to claim 1, wherein the stepped surface of the container is the surface of the stepped portion of the container composed of a large diameter cylinder and a small diameter cylinder. 3. The hole step surface is a step surface of a hole in which a hole on the upper surface side of the rotor having a small turning radius of the sample hole has a large diameter and a hole on the lower surface side having a large turning radius has a small diameter. The rotor for a centrifuge according to claim 1 or 2. 4. A structure for widening the gap between the container step surface and the hole step surface, wherein the hole step surface is a surface perpendicular to the hole axis, and the container step surface is inclined with respect to the hole step surface. The rotor for a centrifugal separator according to claim 1, 2, or 3. 5. A structure for widening the gap between the container step surface and the hole step surface, wherein the container step surface is a surface perpendicular to the hole axis and the hole step surface is inclined with respect to the container step surface. The rotor for a centrifugal separator according to claim 1, 2, or 3. 6. A structure in which a gap between the container step surface and the hole step surface is widened, and a washer having a tapered bottom surface is sandwiched between the container step surface and the hole step surface. Claims 1, 2, or 3
The rotor for a centrifuge according to the item.