JP2014188474A - Centrifugal machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve miniaturization of an outer shape and cost reduction by using an inexpensive proper-size protector suited to the size of a rotor chamber of a centrifugal machine.SOLUTION: A centrifugal machine includes a rotor that is rotatively driven, a rotor chamber that houses the rotor, and a protector 6 that is provided on the outer periphery of the rotor. In the protector 6, steel plates 40, 41 and 42 are wound and stacked. A weld location of the protector 6 is arranged in such a manner as to avoid the same direction and a facing direction on a circumference. Thus, average strength of the protector 6 is maintained, and deformation is set small.

Description

  The present invention relates to a centrifuge having a rotor that is a high-speed rotating body, and more particularly to ensuring its safety.

  A centrifuge injects a sample to be separated (for example, culture solution or blood) into a tube or bottle and inserts it into a rotor. By rotating the rotor at a high speed, centrifugal force is applied to the sample to separate and purify the sample. Do. The rotational speed varies depending on the application, and a product group ranging from a low speed (the maximum rotational speed is several thousand revolutions) to a high speed (the maximum rotational speed is 150,000 rpm) is commercially available. In addition, small centrifuges to large centrifuges are lined up so that the volume of samples that can be separated at a time can be handled from as small as several tens of mL to as large as several L.

  By the way, as described in Patent Document 1 below, in order to quickly separate the sample, a large centrifugal force is required, and a large centrifugal force is also applied to the rotor, thereby generating an internal stress. Manufacturers of centrifuges are designed with sufficient margin so that accidents such as destruction do not occur. In the following Patent Document 2, the following Patent Document 3, the following Patent Document 4, the following Patent Document 5, the following Patent Document 6, and the like, many inventions relating to defense in the case of rotor breakdown have been made.

  In addition, centrifuges used in laboratories and laboratories are a relatively large class of laboratory equipment, and thus users are demanded to reduce the size. In particular, among the centrifuges, large-scale centrifuges have a prominent area compared to small ones, and this tendency is remarkable.

JP 2005-349260 A JP-A-50-56888 JP 2001-104827 A JP-A-2005-230744 JP 2005-305400 A JP 2005-349260 A

  Generally, a centrifuge has a rotor chamber in which a rotor rotates, and a cooling pipe is wound around the rotor chamber (some of them are not wound). When the cooling pipe is wound, a heat insulating layer made of a heat insulating material is provided around the cooling pipe, a cylindrical protector is disposed around the heat insulating layer, and a box-shaped frame is generally used as the outermost shell.

  Here, as described in Patent Document 5, a conventional centrifuge employs a thick protector according to the rotational energy, and deforms or rotates the protector when the rotor is broken. To absorb energy. To this end, the protector deformed by the broken rotor can be moved in the direction of rotation of the rotor within the frame, and in order to prevent the protector from being deformed and deforming the frame, It is necessary to secure a large space between the inner surface of the frame and the protector so that the protector is deformed by the broken rotor and does not come into contact with the protector even if it rotates in the rotation direction.

  Here, the size of the rotor chamber is determined by the size of the rotor to be used, and the necessary thickness of the surrounding heat insulating layer is substantially determined by how much the cooling is performed. Therefore, it is most suitable that the protector is arranged so as to surround the heat insulating layer. However, selection of the protector has the following restrictions. Thick protectors generally use commercially available steel pipes, but the steel pipe size is a standard product and is not available in any size. In particular, the larger the steel pipe size, the smaller the degree of freedom in selecting the size, and the larger centrifuge requires a larger size steel pipe, so the options are narrow and rarely match the right size (a lot to make a right size custom) It is not realistic to manufacture steel pipes at once.) In that case, it may be possible to adopt a size that is slightly larger, but the gap between the heat insulation layer and the protector will be made useless, and the user will be away from the miniaturization.

  The present invention has been made in view of such a situation, and an object of the present invention is to reduce the size of the outer shape and reduce the cost by using an inexpensive and appropriate size protector that matches the size of the rotor chamber. It is to provide a centrifuge that can.

  One embodiment of the present invention is a centrifuge. The centrifuge includes a rotor that is rotationally driven, a rotor chamber that houses the rotor, and a protector that is provided on an outer periphery of the rotor chamber. The protector winds one or more metal plates. It is characterized by a stacked structure.

  In the above aspect, the protector is characterized in that the metal plate is wound twice or more over the entire circumference.

  The said aspect WHEREIN: The welding location of the said metal plate is arrange | positioned avoiding the same direction on the circumference of the said protector, and a facing direction.

  In the aspect described above, when n metal plates are wound in an overlapping manner, the respective welded portions are arranged so as to be shifted by (180 / n) ° or (180 / n + 180) °.

  It should be noted that any combination of the above-described constituent elements, and those obtained by converting the expression of the present invention between methods and systems are also effective as aspects of the present invention.

  According to the present invention, an appropriately sized protector that is generally not commercially available as a steel pipe can be manufactured at low cost, and the IEC standard can be used without increasing the outer shape of a centrifuge that is desired to be downsized, particularly a large centrifuge. It is possible to ensure safety in compliance with the standards.

1 is a side sectional view of a first embodiment of a centrifuge according to the present invention. The plane sectional view of the protector which consists of one sheet of steel in a 1st embodiment. The plane sectional view of the protector which consists of the three steel plates in the 2nd embodiment of the present invention. The exploded perspective view. The plane sectional view of the protector which consists of four steel plates in the 3rd embodiment of the present invention.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same or equivalent component, member, process, etc. which are shown by each drawing, and the overlapping description is abbreviate | omitted suitably. In addition, the embodiments do not limit the invention but are exemplifications, and all features and combinations thereof described in the embodiments are not necessarily essential to the invention.

  FIG. 1 is a schematic configuration of a first embodiment of the present invention, and shows a side sectional view of a centrifuge (centrifuge) 100 as viewed from the side. A rotor 1 that contains a sample to be centrifuged and rotates at high speed is attached to an output shaft of a motor 20, and the motor 20 is fixed to a motor base 8 that is a part of a frame via a damper 11. A rotor chamber 2 is formed around the rotor 1 by a bowl 3 made of a material that is not easily rusted, such as stainless steel, and the rotor 3 is cooled around the bowl 3 to prevent a temperature rise due to rotation of the rotor 1. The pipe 4 is wound. Around the cooling pipe 4, there is a heat insulating layer 5 made of a foam material or the like, and a protector 6 is disposed on the outside thereof. Further, a control unit 19 for controlling the operation of the motor 20 and the like is also provided around the protector 6. The frame is usually manufactured from sheet metal or the like, and is formed as a composite body such as an outer outer frame 7, a motor base 8, a rear plate 9, and a front plate 10, and these are collectively referred to as a frame. Legs 15 are provided on the bottom surface of the outer frame 7.

  A compressor 12, a condenser 13 and a fan 14 for performing cooling using the cooling pipe 4 are housed in the lower part of the frame (below the motor base 8).

  A door packing 16 is provided in the vicinity of the upper opening of the rotor chamber 2, and the upper opening can be opened and closed by a door 17 so that a sample attached to the rotor 1 can be taken in and out. An operation display unit 18 is disposed on the upper surface of the frame.

  Since this embodiment is characterized by the structure of the protector 6, the protector 6 will be described below. As described above, when the outer diameter of the rotor chamber 2 is increased, a steel pipe having an appropriate size corresponding to the outer diameter may not be commercially available. For this reason, in this Embodiment, the steel plate as a metal plate is wound by arbitrary magnitude | sizes, a steel pipe is made, and it employ | adopts as the protector 6. FIG. However, when a steel plate is wound, a thicker one cannot be wound. When the single-layer winding of the steel plate is used, the thickness of the protector 6 is reduced, and the amount of deformation of the protector 6 is increased during the rotor destructive test. There is a problem that the external size of the machine becomes large. Therefore, in the present embodiment, as shown in FIG. 2A or 2B, one steel plate 30 is wound so that the steel plates 30 are stacked in a double layer or more over the entire circumference of the protector 6. I have to. The steel plate 30 is welded so that the inner welded portion 30a and the outer welded portion 30b maintain the tube shape. In addition, the inner side welding part 30a and the outer side welding part 30b are good to be performed continuously thru | or intermittently over the height direction full length of the protector 6. FIG. The same applies to other embodiments.

  As shown in FIG. 3 of the above-mentioned Patent Document 5, the rotor 1 is usually broken into two parts in a centrifuge destructive test, and these fragments jump out in the direction of 180 °. It is preferable to arrange the welded part avoiding the same direction and facing. In the example of FIG. 2A, when the broken rotor 1 jumps out in the direction of the arrow A, the welded portions 30a and 30b whose circumferential positions overlap each other are broken, and the strength is lowered and the deformation is increased. There is sex. For this reason, when the protector 6 is produced by winding a single steel plate 30, the welded portions 30a and 30b do not overlap as shown in FIG. 2B, and the same direction and the facing direction on the circumference are avoided. It is desirable to be arranged. In the case of FIG. 2B, the welded portions 30a and 30b are shifted by 90 ° in the circumferential direction.

  According to the present embodiment, the following effects can be achieved.

(1) By manufacturing the protector 6 by winding the steel plates 30, it is possible to obtain a protector 6 of an appropriate size that is inexpensive and suitable for the size of the rotor chamber 2. Can be achieved.

(2) A required thickness can be ensured by adopting a configuration in which the steel plate 30 is wound more than twice over the entire circumference of the protector 6. Thereby, the deformation amount of the protector 6 at the time of a rotor destructive test can be made small, and the clearance gap between the protector 6 and a flame | frame can be made small according to it, and it can contribute to size reduction.

(3) As shown in FIG. 2B, when the welded portions 30a and 30b of the protector 6 are arranged avoiding the same direction and the facing direction on the circumference, the welded portion is damaged due to the collision of the rotor 1. In this respect, the deformation of the protector 6 can be reduced.

  3 and 4 show a protector 6 according to the second embodiment of the present invention. In this case, the protector 6 is configured by winding up three steel plates 40, 41, and 42. When winding multiple steel plates, the innermost first steel plate is welded into a circular tube, the second and subsequent plates are wound around it, and the gap is welded to the inner steel plate. It can be made by following. At that time, the risk at the time of fracture of the weld is dispersed by shifting the position of the weld. That is, in the case of FIGS. 3 and 4, the inner steel plate 40 is wound in a cylindrical shape, welded at the welded portion 40a, the intermediate steel plate 41 is wound on the outer side, and the welded portion 41a is welded to the inner steel plate 40. Further, an outer steel plate 42 is wound around the outer side, and welded to the intermediate steel plate 41 at the welded portion 42a to constitute a cylindrical steel pipe as a whole.

  In 2nd Embodiment, the welding location of each steel plate 40,41,42 is dispersively arrange | positioned, for example, the broken rotor jumped out in the direction of B, and destroyed the welding part 40a arrange | positioned in the B direction. Even in this case, the strength is maintained by the welds 41a and 42a arranged in the other two directions. As described above, in the centrifuge destructive test, the rotor 1 is broken into two parts, and these fragments jump out in the direction of 180 °. Therefore, when the welded parts are dispersed, avoid welding in the same direction on the circumference and facing each other. Place a place. In FIG. 3, the welding locations are shifted by 60 °, and a certain level of strength can be maintained regardless of the direction in which the rotor protrudes. Moreover, strength can be improved by stacking a plurality of steel plates.

  Thus, according to the second embodiment, the average strength of the protector 6 is maintained by dispersing a plurality of steel plates and by dispersing the welded portions that appear when the protector is produced by the steel plates, The deformation can be reduced.

  FIG. 5 shows a protector 6 according to the third embodiment of the present invention, in which four steel plates 50, 51, 52, 53 are rolled up. The welds 50a, 51a, 52a, 53a are arranged at intervals of 45 ° in the circumferential direction, and a certain level of strength is maintained regardless of the direction in which the broken rotor jumps out. At this time, for example, it can be said that the welded portion 50a in the direction C is substantially the same even in the direction C 'facing the rotor, considering that the rotor protrudes in the 180 ° direction.

  When n sheets of steel plates are wound in this way, the respective welded portions are arranged to be shifted by (180 / n) ° or (180 / n + 180) ° so that the respective welded portions are protected against the rotor breakage. It becomes the most average distribution.

  According to the third embodiment, the strength of the protector can be further improved and the deformation can be reduced by increasing the number of rolled steel sheets and shifting the welding locations.

  The present invention has been described above by taking the embodiment as an example. However, it is understood by those skilled in the art that various modifications can be made to each component and each processing process of the embodiment within the scope of the claims. By the way. Hereinafter, modifications will be described.

  The metal plate for configuring the protector 6 is not limited to a steel plate, and iron, iron alloy, aluminum alloy, or the like can be used depending on the application.

DESCRIPTION OF SYMBOLS 1 Rotor 2 Rotor chamber 3 Bowl 4 Cooling piping 5 Heat insulation layer 6 Protector 7 Outer frame 8 Motor base 9 Rear plate 10 Front plate 11 Damper 12 Compressor 13 Condenser 14 Fan 15 Leg 16 Door packing 17 Door 18 Operation display part 19 Control Part 20 Motor 30, 40, 41, 42, 50, 51, 52, 53 Steel plate 30a, 30b, 40a, 41a, 42a, 50a, 51a, 52a, 53a Welded part

Claims (4)

In a centrifuge that includes a rotor that is driven to rotate, a rotor chamber that houses the rotor, and a protector that is provided on the outer periphery of the rotor chamber.
The centrifuge characterized in that the protector has a structure in which one or a plurality of metal plates are wound.   The centrifuge according to claim 1, wherein the protector has a metal plate wound twice or more around the entire circumference.   The centrifuge according to claim 1 or 2, wherein the welded portion of the metal plate is arranged so as to avoid the same direction and the facing direction on the circumference of the protector.   3. When n sheets of the metal plates are stacked and wound, the respective welded portions are arranged so as to be shifted by (180 / n) ° or (180 / n + 180) °. Centrifuge.