JP5812855B2 - Centrifuge bucket and method for manufacturing centrifuge bucket - Google Patents

Description

  The present invention relates to a centrifuge bucket attached to a swing rotor of a centrifuge.

  Centrifuges are used in a wide range of fields such as medicine and pharmacy. In addition, there is a centrifuge in which a plate having a large number of sample holes can be installed in order to apply centrifugal force to a large number of samples at the same time. In a centrifuge that can install a plate, a centrifuge bucket is attached to a swing rotor, and the plate is installed in the centrifuge bucket. Further, since the necessary centrifugal force varies depending on the application, the rotational speed of the centrifuge varies. In a centrifuge that requires high speed rotation (for example, 5000 rpm / min or more), a very high centrifugal force is applied. Therefore, it is necessary to make the centrifuge bucket light and strong, and to make the plate difficult to break. Therefore, Patent Document 1 discloses a centrifuge bucket manufactured by aluminum cutting and an adapter disposed between the plate and the centrifuge bucket. On the other hand, in a centrifuge having a relatively low speed (for example, 2000 rpm / min, 1000 G or less), a centrifuge bucket is manufactured by bending a metal plate in order to reduce costs.

  FIG. 1 shows an example of a general plate. 1A is a plan view of the plate, FIG. 1B is a front view, FIG. 1C is a cross-sectional view taken along line GG in FIG. 1A, and FIG. 1D is a stack of a plurality of plates. It is GG sectional drawing at the time. The plate 130 has a plurality of sample holes 131 for containing a sample, and an outer peripheral wall 132 extending to a position lower than the bottom surface 133 of the sample hole 131 by a predetermined length d at the outer peripheral portion. Normally, the outer peripheral wall 132 spreads as the position is lower, and can be overlapped on a table or the like as shown in FIG. The plate is often required to be transparent, and is often formed of polystyrene or polypropylene having a thickness of about 1 mm.

  FIG. 2 shows a configuration example of a swing rotor and a centrifuge bucket of a conventional low-speed centrifuge. 2A is a plan view, and FIG. 2B is a cross-sectional view taken along line HH in FIG. The swing rotor 110 has a bucket holding part 111, a connecting part 112, a rotating shaft 113, and a trunnion pin 114. The rotating shaft 113 is connected to a driving source such as a motor. A set of bucket holding portions 111 is disposed at a position sandwiching one centrifuge bucket, and trunnion pins 114 are provided on opposite surfaces of the bucket holding portions 111. The connecting part 112 connects the rotating shaft 113 and a pair of bucket holding parts 111. FIG. 2 shows an example in which two sets of bucket holding portions 111 are provided. An example in which two centrifuge buckets 920 are attached to the swing rotor 110 and a plate is disposed only in the centrifuge bucket on the right side of the figure is shown. The centrifuge bucket 920 is attached to the trunnion pin 114 so that it can rotate at an angle corresponding to the centrifugal force. The plate 130 is disposed on the bottom plate 923 of the centrifuge bucket 920. When the rotating shaft 113 rotates, the entire swing rotor 110 rotates. The centrifuge bucket 920 changes the angle according to the centrifugal force so that the plate 130 (the sample injected into the plate 130) receives a force obtained by synthesizing the centrifugal force and the gravity on the bottom plate 923 side.

  FIG. 3 is a diagram showing the relationship between the centrifuge bucket and the plate when a plate with a deep sample hole is installed. 3A is a cross-section at the position JJ in FIG. 2A, and FIG. 3B is a cross-section at the position H-H in FIG. The plate 230 has a sample hole 231 deeper than the plate 130 of FIG. Also in the case of the plate 230, the outer peripheral wall 232 extends to a position lower than the bottom surface 233 of the sample hole 231 by a predetermined length d.

JP-A-9-155235

  The centrifuge bucket 920 shown in FIGS. 2 and 3 is a centrifuge bucket that can be used when rotating at a low speed as described above. In the case of this centrifuge bucket, the cost can be reduced, but if the rotational speed is increased, the plate and the centrifuge bucket may be damaged. Patent Document 1 discloses a technique for arranging a plate in a centrifuge for high-speed rotation, and shows an adapter arranged between the plate and the centrifuge bucket. However, the centrifuge bucket disclosed in Patent Document 1 is expensive because it is manufactured by cutting a material such as aluminum. Moreover, an adapter is further required. As described above, there are only an inexpensive folding bucket for a centrifugal separator and an expensive cutting bucket for a centrifugal separator. Therefore, if you want to rotate at a slightly higher speed than can be used with a bent centrifuge bucket (which is significantly slower than the allowable speed of a high-speed centrifuge, but the allowable speed of a low-speed centrifuge Even when the rotational speed is slightly higher than the speed (for example, about 2000 to 4000 revolutions / minute), an expensive centrifuge bucket and adapter had to be used.

  This invention is made | formed in view of such a subject, and it aims at raising the permissible rotational speed of the bucket for low speed centrifuges.

  The centrifuge bucket of the present invention is formed by bending a metal plate, and includes plate holding means and attachment means. The plate holding means holds a plate having a plurality of sample holes for containing the sample and an outer peripheral wall extending to a position lower than the bottom surface of the sample hole by a predetermined length in the outer peripheral portion. The attachment means is attached to the swing rotor of the centrifuge so that it can rotate at an angle corresponding to the centrifugal force. The plate holding means has a bottom plate having a sample region facing the bottom surface of the sample hole and an outer peripheral wall region facing the outer peripheral wall. On the bottom plate, a convex portion that prevents the bottom plate from being bent is formed only in a part of the sample region. Moreover, the convex part is extruded so that it may become height more than predetermined length in the direction of the bottom face of the sample hole of a plate.

  According to the centrifuge bucket of the present invention, the convex portion for preventing the curvature of the bottom plate is formed only in the sample region. Further, the convex portion is in contact with the sample hole itself of the plate or another sample hole near the sample hole. Therefore, the curvature of the bottom plate can be prevented. Further, when supporting the sample hole itself of the plate, the plate can be prevented from being damaged by the centrifugal force applied to the sample hole. Moreover, even if the sample hole is not in contact with the convex portion, the nearby sample hole is in contact with the convex portion, so that the moment generated by the centrifugal force can be reduced, and the plate can be prevented from being damaged. Therefore, the permissible rotational speed of the low-speed centrifuge bucket can be increased.

The figure which shows the example of a general plate. The figure which shows the structural example of the swing rotor of the conventional low-speed rotation centrifuge, and the bucket for centrifuges. The figure which shows the relationship between the bucket for centrifuges and a plate at the time of installing the plate of a deep sample hole type. The figure which shows the example which the outer peripheral wall vicinity damaged. The figure which shows the example which the bucket for centrifuges deform | transformed. The figure which shows the example which the bucket for centrifuges deform | transformed and the center part of the plate was damaged. The figure which shows the structure which attached the bucket for centrifuges of this invention to the swing rotor. Another figure which shows the structure which attached the bucket for centrifuges of this invention to the swing rotor. The figure which shows the structure of the bucket for centrifuges of this invention. The figure which shows the sample area | region and outer peripheral wall area | region of the bucket for centrifuges. The figure which shows the relationship between the bucket for centrifuges of this invention and a plate at the time of installing the plate of a type with a deep sample hole.

  Hereinafter, embodiments of the present invention will be described in detail. In addition, the same number is attached | subjected to the structure part which has the same function, and duplication description is abbreviate | omitted.

[analysis]
Examples of breakage when the rotational speed is increased using the low-speed centrifuge bucket shown in FIG. 2 are shown in FIGS. FIG. 4 is a diagram showing an example in which the vicinity of the outer peripheral wall is damaged, FIG. 5 is an example in which the centrifuge bucket is deformed, and FIG. 6 is a diagram in which the centrifuge bucket is deformed and the central portion of the plate is damaged. It is an example. 4A is a cross section at the position JJ in FIG. 2A, and FIG. 4B is a cross section at the position HH in FIG. 2A.

  First, the result of FIG. 4 will be examined. Only the outer peripheral wall 232 of the plate 230 contacts the bottom plate 923 of the centrifuge bucket 920, and a gap 940 exists between the bottom surface 233 of the sample hole 231 and the bottom plate 923 of the plate (see FIGS. 2 and 3). . Therefore, the centrifugal force applied to the sample hole 231 or the injected sample at the outer peripheral wall 232 is supported only by the outer peripheral wall 232. Therefore, it is necessary to support the sample hole 231 itself. 5 and 6 show a bottom plate 923 'deformed by centrifugal force. FIG. 6 shows an example in which the plate is damaged at the central portion 191 due to the deformation of the bottom plate. These deformation and breakage require reinforcement of the centrifuge bucket.

  In order to support the sample holes 131 and 231 themselves, it is desirable to support them with a member that contacts the entire bottom surfaces 133 and 233 of the sample holes. However, if the structure that contacts the entire bottom surfaces 133 and 233 is formed of a plate, the above-described deformation problem cannot be solved. Moreover, if the structure which contacts the whole bottom face 133,233 is comprised with a block (thick member), it will become heavy, and since it will receive to the influence of centrifugal force, it will have to reinforce the whole bucket for centrifuges. .

  Therefore, let us reconsider the cause of the damage in the vicinity of the outer peripheral wall. Although it is considered that the sample hole 231 or the injected sample is subjected to the centrifugal force, it is the upper side (the damaged portion 290) of the outer peripheral wall 232 that is damaged. Therefore, it seems that the moment proportional to the distance from the part to which the centrifugal force is applied and the part to which it is damaged also has influence. Therefore, if it is possible to prevent an excessive moment from being applied to a part of the plate 230 by supporting a part of the sample holes, it is considered that the allowable rotational speed can be increased.

  7 and 8 show a configuration in which the centrifuge bucket of the present invention is attached to a swing rotor. 7 and 8 show an example in which two centrifuge buckets 120 are attached, and FIG. 7 shows an example in which a shallow plate 130 is arranged in the right centrifuge bucket 120. FIG. 8 shows an example in which a deep plate 230 is disposed in the centrifuge bucket on the right side. 7A is a plan view, FIG. 7B is a cross-sectional view taken along the line AA in FIG. 7A, FIG. 8A is a plan view, and FIG. 8B is a cross-sectional view taken along the line B- in FIG. It is B sectional drawing. The swing rotor 110 is the same as the swing rotor of FIG. The plates 130 and 230 are the same as the conventional plates shown in FIGS.

  FIG. 9 is a view showing the structure of the centrifuge bucket of the present invention. 9A is a plan view, FIG. 9B is a side view, FIG. 9C is a cross-sectional view taken along the line CC in FIG. 9A, and FIG. 9D is a cross-sectional view along the line D- in FIG. It is D sectional drawing. FIG. 10 is a diagram showing a sample region and an outer peripheral wall region of the centrifuge bucket. FIG. 10A is a plan view showing a sample region, and FIG. 10B is a plan view showing an outer peripheral wall region. The centrifuge bucket 120 is formed by bending a metal plate and includes plate holding means 129 and attachment means 128. The plate holding means 129 has a plurality of sample holes 131 and 231 for containing a sample, and a plate 130 having outer peripheral walls 132 and 232 extending to a position lower than the bottom surfaces 133 and 233 of the sample hole by a predetermined length d at the outer peripheral portion. , 230 are held.

  The attachment means 128 is attached to the swing rotor 110 of the centrifuge so that it can rotate at an angle corresponding to the centrifugal force. Specifically, the attaching means 128 may include an insertion hole 121 and a reinforcing plate 122 formed in the side plate of the centrifuge bucket. Then, by inserting the trunnion pin 114 of the swing rotor 110 into the insertion hole 121, the swing rotor 110 can be attached so that the angle can be changed according to the centrifugal force. Therefore, the plate 130 (the sample injected into the plate 130) receives a force obtained by combining centrifugal force and gravity in the direction of the bottom surfaces 133 and 233 of the sample holes 131 and 231. The reinforcing plate 122 is bonded along at least the outer periphery on the upper side of the insertion hole 121. For example, it may be bonded by spot welding. The reinforcing plate 122 serves to prevent the upper side of the insertion hole 121 from being worn by centrifugal force.

  The plate holding means 129 includes a sample region 126 (shaded portion in FIG. 10A) facing the bottom surfaces 133, 233 of the sample holes 131, 231 of the plate and an outer peripheral wall region 127 (FIG. 10) facing the outer peripheral walls 132, 232. 10 (B) shaded portion). On the bottom plate 123, a convex portion 125 that prevents the bottom plate 123 from bending is formed only in a part of the sample region 126. Moreover, the convex part 125 is pushed out to the height of h so that it may become height more than predetermined length d in the direction of the bottom face 133,233 of the sample holes 131,231.

  FIG. 11 is a diagram showing the relationship between the centrifuge bucket of the present invention and the plate when a plate with a deep sample hole is installed. FIG. 11A is a cross-section at the position CC in FIG. 9A when the plate is installed, and FIG. 11B is a position DD in FIG. 9A when the plate is installed. It is the cross section in. The height h of the convex portion 125 is equal to or greater than the predetermined length d, and since the convex portion 125 is not present in the outer peripheral wall region 127, the bottom surface 233 of some sample holes 231 is in contact with the convex portion 125. That is, the plate 230 is supported by the convex portion 125 at a position where the bottom surface 233 is in contact with the convex portion 125. Moreover, although the centrifugal force applied to the sample hole 231 not supported by the convex portion 125 is supported by the nearby convex portion 125, the force can be dispersed because there are several convex portions. Further, since the distance between the power point and the fulcrum can be shortened, the moment can also be reduced. Further, when the height h of the convex portion 125 is longer than the predetermined length d, the outer peripheral wall 232 floats (no longer comes into contact with the bottom plate 123), so that the outer peripheral wall 232 is also supported by the neighboring convex portion 125. However, it is sufficient to support only the weight of the outer peripheral wall 232 (there is no sample because it is an outer peripheral wall), and the moment is small because the distance between the force point and the fulcrum is short. Furthermore, since the convex part 125 should just be formed in a part of sample region 126 of the baseplate 123, it should just be formed by the arrangement | positioning which the baseplate 123 becomes difficult to deform | transform. In addition, since the method of reinforcing by providing unevenness on the flat plate is a well-known method, the position where the convex portion is formed may be determined according to the conventional design method. Further, since the outer peripheral wall region 127 is originally close to the side surface of the centrifuge bucket and thus is difficult to bend, the centrifuge bucket can be sufficiently reinforced without forming the convex portion 125. Therefore, the permissible rotational speed can be increased as compared with the conventional centrifugal bucket for low-speed rotation.

[Experiment]
For confirmation, a centrifuge bucket having a length of 137 mm, a width of 92 mm, and a height of 47 mm between the insertion holes 121 is bent with a stainless steel plate having a thickness of 2 mm, so that the centrifuge bucket shown in FIG. The centrifuge bucket shown in Fig. 1 was manufactured and tested. In the centrifuge bucket shown in FIG. 2, the centrifuge bucket was deformed or the plate was broken at about 1000 G (1000 times the acceleration of gravity). However, it was confirmed that the centrifuge bucket shown in FIG. 9 was not deformed or damaged even at about 1800 G (1800 times the gravitational acceleration).

DESCRIPTION OF SYMBOLS 110 Swing rotor 111 Bucket holding part 112 Connection part 113 Rotating shaft 114 Trunnion pin 120,920 Centrifuge bucket 121 Insertion hole 122 Reinforcement plate 123,923 Bottom plate 125 Protruding part 126 Sample area 127 Outer wall area 128 Attaching means 129 Plate holding Means 130, 230 Plate 131, 231 Sample hole 132, 232 Outer peripheral wall 133, 233 Bottom surface

Claims (2)

It is a shape formed by bending a metal plate,
Plate holding means for holding a plurality of sample holes for containing a sample, and a plate having an outer peripheral wall extending to a position lower than the bottom surface of the sample hole in the outer peripheral portion by a predetermined length;
Mounting means for attaching to the swing rotor of the centrifuge so that it can rotate at an angle corresponding to the centrifugal force;
A centrifuge bucket comprising:
The plate holding means has a bottom plate having a sample region facing the bottom surface of the sample hole and an outer peripheral wall region facing the outer peripheral wall,
On the bottom plate, a convex portion for preventing the curvature of the bottom plate is formed only in a part of the sample region,
The centrifuge bucket according to claim 1, wherein the convex portion is pushed out in a direction toward the bottom surface of the sample hole so as to be higher than the predetermined length so as to be in contact with the bottom surface of the sample hole.   Plate holding means for holding a plurality of sample holes for containing a sample, and a plate having an outer peripheral wall extending to a position lower than the bottom surface of the sample hole in the outer peripheral portion by a predetermined length;
  Mounting means for attaching to the swing rotor of the centrifuge so that it can rotate at an angle corresponding to the centrifugal force;
  With
  The plate holding means has a bottom plate having a sample region facing the bottom surface of the sample hole and an outer peripheral wall region facing the outer peripheral wall,
  The bottom plate is a method for manufacturing a centrifuge bucket in which a convex portion that prevents the bottom plate from being curved is formed only in a part of the sample region,
  Extruding the convex portion so as to be higher than the predetermined length in the direction of the bottom surface of the sample hole so as to contact the bottom surface of the sample hole,
  The centrifuge bucket is formed by bending a metal plate.
  A method of manufacturing a bucket for a centrifuge, wherein

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