JP6779115B2 - centrifuge - Google Patents

Description

The present invention relates to a centrifuge (centrifuge) that rotates a rotor on which a sample is mounted at a high speed.

A centrifuge injects a sample to be separated (for example, culture solution or blood) into a tube or bottle, inserts it into a rotor, and rotates the rotor at high speed to exert centrifugal force on the sample to separate and purify the sample. I do. The rotation speed varies depending on the application, and product groups ranging from low speed (maximum rotation speed is several thousand rotations) to high speed (maximum rotation speed is 100,000 rotations) are commercially available according to the application. At this time, as described in Patent Document 1, a large centrifugal force is required to quickly separate the samples, and a large centrifugal force is applied to the rotor to generate internal stress.
Manufacturers of centrifuge are designed with sufficient margin to prevent accidents such as destruction due to these, but they can be used even in the event of a rotor destruction accident that cannot occur. We are taking measures to ensure the safety of people, and in the international standard based on this idea, we carry out the maximum assumed destruction test assuming an extreme destruction state that can not occur in normal use, and make it safe. It is required to prove. Many of these tests are confirmed by the behavior of the rotor, which has been artificially easily destroyed, when the rotor is destroyed (hereinafter referred to as the "destruction test"). Inventions have been made to protect against such a destructive test by reducing damage to the housing when the rotor is destructive. (For example, Patent Document 2, etc.)
Further, in the above-mentioned international standard, a limit is set on the debris that pops out from the rotor chamber at the time of the rotor destructive test, and not only the above-mentioned damage reduction to the housing but also the space between the door and the housing as described in Patent Document 2 is set. An invention has also been made in which the door packing is divided into two in order to prevent debris from popping out from the gap.

Patent No. 4586426 Japanese Unexamined Patent Publication No. 2016-10755

During the rotor destructive test, the bowl and protector may be deformed into an elliptical shape due to the impact of the rotor fragments split in two. In this case, the bowl in particular may also exert a force on the adjacent or abutting door packing, pulling the door packing away from the table.
In Patent Document 2, an idea is made to make the door packing a double structure for maintenance reasons, and the door packing is the first packing between the table and the bowl and the second packing between the table and the door. Since it is separated into two types, even if the lower first packing is dropped by a deformed bowl or protector, the upper second packing remains between the table and the door. However, when the rotational energy is further increased due to an increase in the volume of the sample to be separated by the centrifuge, the phenomenon of pulling the door packing away from the table cannot be sufficiently suppressed only by the effect of the above two-divided packing. There may be cases. This is a metal bowl made of stainless steel with a thickness of about 1 to 1.5 mm for models with large rotational energy such as high-speed centrifuges and large-capacity centrifuges. This is because, due to the energy at the time of rotor destruction, the prototype may be greatly deformed, and the rotor may rotate and move together with the rotor so as to be dragged by the destroyed rotor.
In this case, when the lower part of the first door packing facing the rotor chamber side comes into contact with a part of the bowl that is rotating and moving, a force that causes the first door packing to be separated from the table works, and the table The first door packing, which is locked so as to sandwich the opening, may come off. Then, when the first door packing is detached, a gap is generated between the table and the door, and there is a possibility that debris pops out when the rotor is broken.
The present invention has been made in view of such problems, and an object of the present invention is to provide an invention for solving the above problems.

The present invention has the following configurations in order to solve the above problems.
Centrifuge of the present invention includes a rotor chamber where the rotor is housed for rotation, the table having the opening provided on the rotor chamber, provided is opened and closed in on the table, closed The door is provided with a door for closing the opening and a bowl-shaped shape provided under the table for accommodating the rotor. Moreover, the bowl upper portion constituting the opening in the bowl-like shape is disposed in the vicinity of the opening in the table, second provided between the upper portion and the lower surface of the table of the bowl It includes a packing and a first packing provided between the upper surface of the table and the lower surface of the door in a closed state. The first packing is attached to the table in a form in which the inner end portion constituting the opening of the table is sandwiched from the upper side and the lower side, and the inner end portion is sandwiched from above and below on the lower surface of the table. It is characterized in that a protrusion is provided on the radial outer side of the opening with respect to the end of the first packing.

Further, the centrifuge of the present invention is further characterized in that a protector is provided around the bowl, and the upper end surface of the protector is located below the protrusion.
Further, it is further characterized that the protrusion of the centrifuge of the present invention is configured to be located on the opening side of the protector.

The lower end of the protrusion of the centrifuge of the present invention is characterized in that above said upper end of said bowl.

Further, the projection of the centrifuge of the present invention is further characterized in that it consists of the bowl by Ri high rigidity material.
Further, the centrifuge of the present invention is further characterized in that a freezing pipe through which a refrigerant flows is wound around the bowl.

According to the present invention, since it is improved that the first door packing is hard to come off, it is possible to further increase the possibility that debris can be prevented from popping out even in a centrifuge having a large rotational energy.

It is sectional drawing which shows the structure of the centrifuge which concerns on embodiment of this invention. It is a partial detailed sectional view which concerns on embodiment of this invention. It is sectional drawing which shows the structure of the conventional centrifuge. It is a partial detailed sectional view in a conventional centrifuge.

Hereinafter, examples of the present invention will be described with reference to the drawings. It should be noted that the following embodiments are merely examples and do not limit the invention. In the following figures, the same parts are designated by the same reference numerals, and repeated description thereof will be omitted.

FIG. 3 is a cross-sectional view showing the structure of a conventional centrifuge. In the centrifuge, a bowl 2 made of a thin metal plate is provided inside a frame 6a and a table 6b, which are a part of a housing made of sheet metal or the like, and the rotor chamber 3 is provided by the bowl 2 and the door 5. The door 5 is defined and attached to the frame 6a and the table 6b with a hinge (not shown) so that the door 5 can rotate in the vertical direction.
The rotor 1 holds the sample to be separated and rotates at high speed, and is supported by the rotating shaft of the motor 4. Since the rotor 1 rotates at high speed, heat is generated by friction with the surrounding air during rotation, and the refrigerating pipe 7 is spirally wound around the outer circumference of the bowl 2 in order to suppress the heat generation, and the refrigerating pipe 7 is a cooling device (FIG. The rotor 1 is cooled through the air in the rotor chamber 2 by connecting to (not shown) and cooling the bowl 2. The outer circumference of the freezing pipe 7 is further surrounded by a cylindrical heat insulating material 10.
In the above configuration, in order to improve the accuracy of temperature control, the bowl 2 around the rotor 1 is thin, and the heat insulating material 10 is made of a thick heat insulating material having low mechanical strength. Therefore, the bowl 2 and the heat insulating material are formed. The mechanical strength of 10 is low. Therefore, in the above configuration, a cylindrical protector 11 made of a thick steel plate is provided between the frame 6a and the heat insulating material 10. The central axis of the cylindrical protector 11 substantially coincides with the rotation axis of the rotor 1, that is, the distance from the rotation axis of the rotor to the protector 11 is approximately equal. The protector 10 is provided to absorb the energy when the rotor 2 is damaged.

In manufacturing the above-mentioned centrifuge, a motor 4, a bowl 2, a heat insulating material 10, a protector 11, and the like are installed inside the frame 6a, and then a table 6b, a door 5, and the like are installed.
Here, the rotor chamber 3 must be sealed with the outside of the rotor chamber so as not to reduce the cooling effect. In this sealing, an elastic body such as rubber is usually used as a packing to substantially realize a sealed state. The place to be sealed is between the door 5 and the table 6b, between the table 6b and the bowl 2, between the bowl 2 and the motor 4, and between the door 5 and the table 6b is the first door packing 8, the table 6b and the bowl. The structure is such that the space between 2 is sealed with the second door packing 9, and the space between the bowl 2 and the motor 4 is sealed with a seal rubber 12.
In this structure, the seal between the door 5 and the table 6b is released when the door 5 is opened, but the seal is maintained between the bowl 2 and the table 6b even when the door 5 is opened. It is in the state of being done. Further, the seal between the bowl 2 and the motor 4 is maintained by the seal rubber 12 regardless of whether the door 5 is opened or closed.
In the present embodiment, as shown in FIGS. 1 and 2, which is a detailed view of FIG. 1, the first door packing 8 extends downward toward the bowl 2 side with the table 6b sandwiched from above and below. A ring-shaped protrusion 13 is provided. In the present embodiment, a ring-shaped circular protrusion is illustrated, but the present invention is not limited to a continuous ring, and a virtual ring-shaped circumference is assumed, and a convex portion is provided in a part thereof. It may be configured.
The lower end position of the protrusion 13 is preferably lower than the lower end position of the first door packing 8, and the lower end position of the protrusion 13 is sufficiently lower than the upper end position of the second door packing 9. More suitable. On the other hand, the lower end position of the projections 13, it is preferable that the upper end portion position of the bowl is formed so as to be located closer to the table.
Further, in the present embodiment, the protrusion 13 is made of a metal part separate from the table 6b, and is fixed to the table with screws or the like at joints provided at predetermined intervals, for example.
In the present embodiment, an example in which the protrusion 13 structure is composed of separate parts is illustrated, but a part of the table 6b may have a convex shape, and the convex shape in this case may be used. The thickness of the convex portion may be thicker than the thickness of the table at the opening of the table 6b, and the thickness of the convex portion is substantially the same as the thickness of the convex portion in the direction away from the opening from the position corresponding to the convex portion. The structure may be such that the thickness of the table 6b is maintained (in other words, the thickness of the table 6b is reduced only in the peripheral portion of the opening of the table 6b).
The material constituting the protrusion 13 is a material that can sufficiently withstand the impact at the time of contact with the bowl 2 and other contact objects during the destructive test of the rotor 1, that is, a material capable of suppressing the movement of the first door packing 8. Anything is preferable, and preferably, it has a metal material such as a steel material (carbon-containing steel or the like) having a higher rigidity than the bowl 2 formed of stainless steel or the like, or has a sufficient thickness, height, and depth to withstand an impact. It may be a material.
As described above, by adopting the protrusion 13 having a convex structure, it is possible to prevent the bowl 2 and other objects from coming into contact with each other in order to separate the first door packing 8 from the table 6b during the rotor 1 fracture test. Further, if it comes into contact with the lower side of the first door packing 8, it is possible to restrict the movement of the first door packing 8 when the first door packing 8 tries to move. Become.
Further, since the protrusion 13 of the present invention has a structure provided around the opening of the table 6b, the effect of suppressing the deformation of the opening is also exhibited during the rotor 1 fracture test.

Although the invention made by the present inventor has been described above based on the embodiment, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the gist thereof.

1 Rotor 2 Bowl 3 Rotor chamber 4 Motor 5 Door 6a Frame 6b Table 7 Refrigeration piping 8 First door packing 9 Second door packing 10 Insulation material 11 Protector 12 Seal rubber 13 Protrusions

Claims (6)

A rotor chamber containing a rotating rotor and
A table provided above the rotor chamber and having an opening ,
A door that is openable and closable on the table and closes the opening when closed.
A bowl provided under the table and having a bowl-shaped shape for accommodating the rotor, and an upper end portion forming an opening in the bowl-shaped shape is arranged in the vicinity of the opening in the table.
A second packing provided between the upper end of the bowl and the lower surface of the table,
A centrifuge comprising a first packing provided between the upper surface of the table and the lower surface of the door in a closed state.
The first packing is attached to the table in a form in which the inner end portion constituting the opening of the table is sandwiched from the upper side and the lower side.
A centrifuge having a protrusion on the lower surface of the table and radially outside the opening with respect to the end of the first packing that sandwiches the inner end from above and below. The centrifuge according to claim 1, wherein a protector is provided around the bowl, and the upper end surface of the protector is located below the protrusion. The centrifuge according to claim 2 , wherein the protrusion is configured to be located closer to the opening side than the protector. The lower end of the protrusion, centrifuge according to any one of claims 1 to 3, characterized in that above said upper end of said bowl. The projections centrifugal machine according to any one of claims 1 to 4, characterized in that it consists of the bowl by Ri high rigidity material. The centrifuge according to any one of claims 1 to 5, wherein a freezing pipe through which a refrigerant flows is wound around the bowl.