JP2011083723A - Swing rotor and centrifuge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifuge swing rotor which can rotate stably without being influenced by the design and processing accuracy of each part of the rotor, and a centrifuge using the swing rotor. <P>SOLUTION: When the arm pin 52 of a bucket is combined with an arm pin holder 53, a two-surface width portion 53B of the arm pin holder 53 is laid just between large-diameter portions 52C of the arm pin 52 to prevent the arm pin 52 from moving more than necessary in the direction of the center axis 52E of the arm pin 52. As a result, even if a center line of the bucket is not aligned with the center line of a bucket receiving portion of a rotor body when the bucket is seated on the bucket receiving portion during rotation of the rotor, a bucket body 40 can move in the axial direction of the arm pin 52 according to a shape of the bucket receiving portion to be seated on the bucket receiving portion without occurrence of partial contact. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a swing rotor for a centrifuge and a centrifuge used in the fields of medicine, pharmacy, genetic engineering, chemical industry, food production, pharmaceutical production and the like.

  A centrifuge is a device that separates fine particles in a sample for each size or specific gravity by accommodating a sample container for containing a sample in a rotor, rotating the rotor to give a centrifugal force to the sample. The centrifuge swing rotor includes a rotor body and a plurality of buckets. The bucket contains the sample to be centrifuged and is suspended from the rotor body. The bucket is supported by a bucket pin that can rotate about an attachment axis. When the rotor stops, the bucket hangs vertically under the influence of gravity. When the rotor is rotating, the bucket is rotated outward by centrifugal force. In many conventional designs of swing rotors for ultracentrifuges, a device is incorporated in the rotor that limits the movement of the rotor body in the direction of the centrifuge (the direction of centrifugal force). Usually, the movement in the outer direction of the rotor body (the direction of centrifugal force) is restricted by leaning against a bucket receiving portion having a bucket in the rotor body.

  As described in Patent Document 1, the swing rotor as described above generally has a hook portion of a bucket attached to an arm provided on the rotor body from a lower portion of the rotor body. For this reason, when attaching the hook part of the bucket to the arm, it is necessary to attach it while confirming from the opening part of the bucket escape part provided on the side surface of the rotor body, and there is a problem that operability is poor. It was.

  In addition to the above, there is a swing rotor 130 of the type shown in FIG. This type of swing rotor 130 is a swing rotor 130 in which a bucket 132 is inserted from above the rotor body 131 and attached. In this swing rotor 130, the rotor body 131 is perpendicular to the upper surface of the rotor body 131 in addition to the cavity 131 </ b> B for attaching a plurality of buckets 132 spaced at equal angles and intervals around a vertical rotation axis. A hole 131D penetrating each of the cavities is provided. The through hole 131D is larger than the maximum diameter of the bucket, and the bucket 132 can pass through the through hole. In addition, two opposing grooves 131E are provided on the side wall of the through hole, and receive the arm pin 152 provided in the cap assembly 150 disposed at the upper part of the bucket. Since the groove 131E does not penetrate to the lower end of the rotor body, the arm pin 152 is supported by the end portion of the groove, so that the rotor body 131 is set to be swingable around the arm pin 152.

Since the bucket mounting state can be easily observed from the top surface, the operability is superior to the bottom mounting type. However, the swing rotor 130 described above needs to have a very high processing accuracy of the cap assembly 150 provided at the top of the bucket 132.
For example, the parts constituting the cap assembly 150 have an arm pin inserted so that a gap that is movable in the axial direction of the bucket can be provided at the top of the cap body for sealing the sample container and the top of the cap body. The arm pin holder 153 is attached to the upper portion of the arm pin holder 153, and the wave type washer 154 having a spring property that enables the arm pin holder 153 to move in the axial direction of the bucket prevents the wave type washer 154 from falling off. It is comprised from the stopper 155 for doing. For these plural parts, a large number of dimensional elements must be manufactured with a dimensional accuracy of about 0.01 to 0.02 mm. In particular, since the arm pin 152 and its holder member 153 are integrated by press-fitting, it is necessary to manufacture both members with high accuracy. In addition, since the arm pin is fixed by press-fitting, it is difficult to press-fit the arm pin 152, and when the press-fitting dimension of the arm pin 152 is not assembled within a predetermined dimensional tolerance, In this case, there is a problem that the contact becomes uneven and the balance during rotation is lost and the rotational vibration is increased. Furthermore, the dimensional tolerance of the press-fitting dimension needs to be very small, and the workability is very bad.

JP 2002-86016 A

    The center of the flange portion of the bucket needs to coincide with the center of the bucket receiving portion of the rotor body during the rotational drive of the swing rotor of the centrifuge. If the dimensional accuracy of each part is poor, there is a possibility that the center of the flange of the bucket and the center of the bucket receiving part of the rotor body will be misaligned, resulting in a problem that balance is lost and rotational vibration increases. .

  An object of the present invention is to provide a swing rotor and a centrifugal separator that can rotate stably without being affected by the design and processing accuracy of each component of the rotor in view of the problems of the prior art as described above. It is intended.

  The above object is provided in the rotor body, a bucket that is attached to the rotor body, accommodates the sample, a cap assembly that is attached to the bucket and has an arm pin, and the bucket is provided while the rotor body is rotating. In a swing rotor in which a flange and a bucket receiving part provided on the rotor body can come into contact, the bucket can be moved in the central axis direction of the arm pin, or attached to the rotor body and the rotor body, A bucket that contains a sample, a cap assembly that has an arm pin attached to the bucket, a flange that is provided on the bucket, and a bucket receiver that is provided on the rotor body while the rotor body is rotating. Contacting swing rotor and connecting to the swing rotor In a centrifuge having a drive unit capable of being connected to and a housing supporting the drive unit, the centrifuge is configured to rotate a swing rotor in which the bucket can move in the central axis direction of the arm pin by the drive unit. Is done.

  It is possible to provide a swing rotor and a centrifuge that can rotate stably without being influenced by the design and processing accuracy of each component of the rotor.

It is a front view of the centrifuge 1 which concerns on the Example of this invention, and shows the cross section in part. It is the upper side figure and side view (longitudinal sectional view) of the rotor in the Example of this invention. It is a side view (longitudinal sectional view) for explaining the operating state of the rotor of the present invention. It is a perspective view of the whole bucket in the Example of this invention. It is an expansion | deployment perspective view of the components of the bucket in the Example of this invention. Top view and side view showing prior art

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the same portions are denoted by the same reference numerals, and repeated description is omitted. Further, in the present specification, description will be made assuming that the up / down / left / right directions of the centrifuge are the directions shown in FIG.

  FIG. 1 is a front view of a centrifuge 1 of the present invention, and shows a part thereof in cross section. The centrifuge 1 includes a rectangular box-shaped housing 2, and the housing 2 is partitioned into two upper and lower spaces by a horizontal partition plate 2A. In the partitioned upper space, a cylindrical chamber 3 having an open top surface is provided. A cooling thermo module (not shown) is disposed on the outer peripheral bottom surface of the chamber 3 to cool the internal space of the chamber 3, that is, the rotor chamber 4. A protective wall 2B is provided around the chamber 3.

  An openable / closable door 10 is provided on the upper side of the chamber 3, and the rotor chamber 4 is sealed by closing the door 10, and the swing rotor 30 is accommodated in the rotor chamber 4. An operation / display unit 13 is provided on the top of the housing 2.

  The drive unit 5 is attached to the partition plate 2A at the lower stage partitioned by the partition plate 2A in the housing 2. The drive unit 5 includes a motor housing 6, and an electric motor 7 as a drive source is provided inside the motor housing 6. The motor housing 6 is fixed to the partition plate 2 </ b> A via a damper 8. The rotating shaft 7A of the motor 7 extends upward into the rotor chamber 4, and a fitting portion 12 is provided at the upper end portion. A fitting hole 31 </ b> A of the swing rotor 30 is inserted and fixed in the fitting portion 12. The swing rotor 30 is rotated by the motor 7 while the swing rotor 30 is configured to be detachable from the drive shaft portion 12. In the case of the ultracentrifuge, when operating, the rotor chamber 4 is depressurized by a vacuum exhaust device (not shown).

  The swing rotor 30 is usually used by selecting a size having a holding hole corresponding to the sample container to be used. A sample container (not shown) filled with a sample is mounted in a holding hole (not shown) of the sample container formed in the bucket 32 of the swing rotor 30.

  Next, the swing rotor 30 of the present invention will be described with reference to FIGS. 2 (1) is a top view of the swing rotor 30 of FIG. 1, and (2) is a longitudinal sectional view. A plurality of buckets 32 are mounted on the swing rotor 30 at equal angular pitches in the circumferential direction. Each bucket 32 is equipped with a sample container (not shown) into which a liquid sample has been injected.

  In the swing rotor 30, the rotor body 31 has a bucket housing cavity 31B for attaching a plurality of buckets 32 spaced at equal angles and intervals around a vertical rotating shaft 31F, and in addition, a vertical direction from the upper surface of the rotor body 31. A through hole 31D reaching each of the cavities is provided, and the through hole is larger than the maximum diameter of the bucket so that the bucket 32 can pass therethrough. Further, pin insertion grooves 31E are provided at two opposing positions on the side wall of the through hole.

  The pin insertion groove 31E is a groove for receiving the arm pin 52 provided in the cap assembly 50 disposed above the bucket, and the center line 40A of the bucket 32 when the bucket 32 rotates in the depth position. And the center line 31G of the bucket receiving portion 31C of the bucket housing cavity 31B are dimensioned. Each bucket 32 is disposed in the bucket housing cavity 31B from above the rotor body 31 through the through hole 31D.

  FIG. 3 is a longitudinal sectional view of the swing rotor 30, and shows a state where the rotor is rotating in the left half in the drawing and a state when the rotor is stopped in the right half. The bucket 32 is suspended vertically downward when the rotor is stopped (right half figure), but when the rotor starts rotating (left half figure), the bucket 32 is horizontally moved by centrifugal force with the arm pin 52 as a fulcrum. Move to rotate. At this time, the contact surface 43A of the flange portion 43 has a slight gap in the bucket receiving portion 31C, but when the swing rotor 30 further rotates at a high speed, the bucket body 40 and the cap body 51 are caused by the centrifugal force applied to the bucket. When the stopper 55 moves in the outer circumferential direction, the wave washer 54 is compressed, and the contact surface 43A of the flange portion 43 of the bucket body 40 is seated on the bucket receiving portion 31C.

  4 and 5 show the detailed assembly state of the bucket 32 and the exploded view of the parts. The bucket 32 includes a lower bucket body 40 and a cap assembly 50 that is screwed to the bucket body 40. The bucket body 40 has a cylindrical body 41 at the lower part, and has a sample container holding hole 42 for receiving and holding a sample container therein. The bucket body 40 has a flange part 43 at the upper part of the cylindrical body 41 and has a flange part. The lower surface side of 43 serves as a contact surface 43A seated on the bucket receiving portion 31C of the bucket housing cavity 31B of the rotor body 31. Further, an internal thread 44 for screwing the cap assembly 50 is provided inside the upper end opening of the bucket body 40. The bucket body 40 is preferably made of a material having a high strength and a low specific gravity, such as a titanium alloy or duralumin.

  The cap assembly 50 is composed of a plurality of parts, and an arm pin 52, an arm pin holder 53, a wave washer 54, a cap body 51 having a male screw 51A for screw fastening to the bucket body 40 at the outer periphery of the lower end. The stopper 55 is assembled with a screw 56.

  The cap body 51 has a shaft portion 51B at the top, and the shaft portion is formed with two opposing surfaces 51C in parallel, and is provided with a vertically long slot 51D drilled at right angles to the two surfaces. Has an internal thread 51E. The cap body is preferably made of light weight and high strength duralumin or titanium alloy.

  The arm pin 52 inserted into the elongated hole 51D of the cap body 51 has a symmetrical shape, and has an end 52A that fits into the pin insertion groove 31E of the rotor body 31, and from the pin insertion groove 31E. Is also processed to be slightly smaller, and smoothly slides when the bucket 32 rotates (swings).

  The diameter of the central cylindrical portion 52 </ b> B of the arm pin 52 is dimensioned so as to fit with the semicircular R portion 53 </ b> C on the side surface of the arm pin holder 53. Further, the arm pin 52 has two large-diameter portions (stopper portions) 52C symmetrically between the both end portions 52A and the central cylindrical portion 52B, and two opposing flat surfaces 52D are provided for each large-diameter portion 52C. There are places. This part is machined into a shape slightly smaller than the shape of the elongated hole 51D of the cap body 51 when viewed from the direction of FIG. 5, and the arm pin 52 can be inserted into the elongated hole 51D without any trouble. It has come to be.

  Further, when this portion is combined with the arm pin holder 53, the two-sided width portion 53B of the arm pin holder 53 just enters between the large diameter portions 52C, so that the arm pin 52 is more than necessary in the direction of the central axis 52E of the arm pin. It will prevent movement.

  In the state where the arm pin 52 is assembled to the cap body 51, the movement of the bucket in the direction of the center line 40A is regulated by the long hole 51D, the arm pin holder 53, and the wave washer 54. Regarding the rotation direction, the arm pin 52 can move by the gap between the diameter of the central cylindrical portion 52B of the arm pin 52 and the elongated hole 51D of the cap body 51. As a material of the arm pin 52, it is desirable to select maraging steel, high strength steel, or titanium alloy which is a high strength material and has a large elastic modulus.

  The arm pin holder 53 is a cylindrical member, has a fitting hole 53A that fits into the outer shape of the shaft portion 51B in the upper part of the cap body 51 in the center, and has a two-sided width portion 53B on the outer peripheral surface. A semicircular R portion 53C is provided below the two-surface width portion. The arm pin holder 53 restricts movement of the arm pin 52 in the lateral direction, and when the bucket 32 is rotated by rotation, the bucket receiving portion 31C and the flange portion 43 of the rotor body 31 until the bucket becomes horizontal. The pressure is applied to the wave washer 54 so that the arm pin 52 moves so that the bucket 32 contacts the bucket receiving portion 31C of the rotor body 31 during high speed rotation. Operate to communicate.

  The wave washer 54 has a stopper 55 which is fixed to the cap body 51 by screws 56 on the upper surface of the arm pin holder 53 inserted into the shaft part 51B of the cap body 51 and the upper end of the shaft part 51B of the cap body 51. It arrange | positions between and the arm pin 52 is pressed on the lower end part (bucket main body side) of the long hole 51D. For this reason, a state is maintained in which the bucket 32 can swing smoothly until the bucket receiving portion 31C of the rotor body 31 and the contact surface 43A of the flange portion 43 rotate to the normal position. Further, when a centrifugal force of a predetermined level or more is applied to the bucket 32, the bucket 32 moves by the amount of compression of the wave washer 54, and the contact surface 43A of the flange portion 43 is moved to the bucket receiving portion 31C. Can be seated. As the material of the wave washer 54, spring steel or stainless spring steel is used.

  Even if the bucket center line 41A and the center line 31G of the bucket receiving portion 31C are displaced when the contact surface 43A of the bucket receiving portion 31C and the flange portion 43 is seated, the bucket 32 configured as described above is Since the body 40 can move in the direction of the central axis 52E of the arm pin 52 in accordance with the shape of the bucket receiving portion 31C of the rotor body, the contact surface 43A of the bucket receiving portion 31C and the flange portion 43 is seated without contact with each other. be able to.

  That is, since the bucket 32 is configured to be movable in the central axis direction of the arm pin 52, the deviation between the bucket center line 41A and the center line 31G of the bucket receiving portion 31C due to a deviation in processing tolerance can be eliminated. A swing rotor with good stability can be obtained.

DESCRIPTION OF SYMBOLS 1 Centrifugal separator 2 Housing | casing 2A Partition plate 2B Protective wall 3 Chamber 4 Rotor room 5 Drive part 6 Housing
7 Motor 7A (Motor) Rotating shaft 8 Damper
DESCRIPTION OF SYMBOLS 10 Door 12 Drive shaft part 13 Operation / display part 30 Swing rotor 31 Rotor body 31A Drive shaft hole
31B Bucket accommodating cavity 31C Bucket receiving portion 31D Through hole 31E Pin insertion groove
32 buckets
40 Bucket body 41 Cylindrical body 42 Sample container holding hole
43 Flange 43A Contact surface 44 Female thread 50 Cap assembly 51 Cap body 51A Male thread
51B Shaft portion 51C Opposing surface 51D Elongated hole 51E Female thread 52 Pivot pin 52A Both ends 52B Central cylindrical portion 52C Large diameter portion 52D Flat surface 53 Pivot pin holder 53A Fitting hole 53B Two-sided width portion 53C Semicircular R portion 54 Wave washer
55 Stopper
56 screws

Claims (3)

A rotor body and a bucket attached to the rotor body and containing a sample;
A cap assembly with arm pins attached to the bucket;
During the rotation of the rotor body, in the swing rotor in which the flange provided in the bucket and the bucket receiving portion provided in the rotor body can contact,
A swing rotor characterized in that the bucket is movable in the central axis direction of the arm pin. The swing rotor according to claim 1, wherein the arm pin has a large-diameter portion, and movement of the bucket over a predetermined amount is restricted. A rotor body and a bucket attached to the rotor body and containing a sample;
A cap assembly with arm pins attached to the bucket;
While the rotor body is rotating, a swing rotor in which a flange provided in the bucket and a bucket receiving portion provided in the rotor body are in contact with each other,
In a centrifuge having a drive unit that can be connected to the swing rotor and a housing that supports the drive unit,
A centrifugal rotor characterized in that a swing rotor capable of moving the bucket in the central axis direction of the arm pin is driven to rotate by the drive unit.