Patent Application
20130316889
The present application claims priorities from Japanese Patent Application No. 2012-117322 filed on May 23, 2012, and Japanese Patent Application No. 2013-085703 filed on Apr. 16, 2013, the contents of which are hereby incorporated by reference into this application.
The present invention relates to centrifuges for use in the fields of medical science, pharmaceutical science, genetic engineering, and others, and relates to a sample container in a cylindrical or non-cylindrical shape for a centrifuge (a centrifugal machine) having an angle rotor.
A centrifuge for use in separation of a liquid sample includes a rotor which holds a plurality of sample containers having the liquid sample accommodated therein in sample-container holding holes equally arranged on the circumference of a circle and a driving means such as a motor for driving the rotor for rotation. With the rotor rotating at a high speed under atmospheric pressure or a reduced pressure in a rotor chamber, the liquid sample in the sample containers is centrifuged to collect a target substance.
A rotor for a centrifuge has been known from, for example, Japanese Patent Application Laid-Open Publication No. 2008-119649 (Patent Document 1).
Conventionally, each lid-equipped sample container 150 for use in the angle-type rotor 130 has a capacity of 2 ml to 1,000 ml in practical use, according to the intended purpose. Also, the number of holding holes 132 for sample containers formed in each rotor 130 is varied from about four to twenty. In general, the rotor 130 is manufactured by using a light-weight, high-strength aluminum alloy, titanium alloy, carbon-fiber composite material, or others. Commercially-available examples of the rotor 130 include a rotor that can accommodate six sample containers each having a capacity of 300 ml (hereinafter referred to as six 300-ml sample containers), a rotor that can accommodate six 500-ml sample containers, and a large-capacity angle rotor that can accommodate four to six 1,000-ml sample containers. With changes of the times, the capacity of each sample container has been increased. With the increase in capacity of the sample container, the size of the rotor body has also been increased. For example, a rotor for 300-ml to 1,000-ml sample containers has a size with a maximum diameter of its rotor body substantially exceeding 300 mm.
Meanwhile, the rotor is attached to and removed from the centrifuge by an operator. Centrifuge manufacturers including the applicant have been endeavoring to reduce weight and improve operability of the rotor by contriving the structure of the rotor. Furthermore, with an increase in size of the sample container, the sample capacity that can be centrifuged at one time has been increased. In recent years, a centrifuge using a large-capacity angle rotor that can accommodate four 1,000-ml sample containers has been widely used. Also, a sample container disclosed is equipped with a lid as disclosed in Japanese Patent Application Laid-Open Publication No. 2004-290746 (Patent Document 2) to prevent leakage of a sample during centrifuging, and the lid 152 has a through hole 153A for removal (refer to
Related art is also disclosed in Japanese Patent Application Laid-Open Publication No. 2011-11131 (Patent Document 3).
In general, to efficiently collect target substances from a liquid sample in a centrifugal process, the rotation speed of the rotor is increased to increase the centrifugal acceleration to be applied to the liquid sample to enhance a centrifugal effect so that the target substances are quickly settled, or the amount of the sample that can be processed at one time is increased so that a collection ratio is improved. Also, for a reduction in cost for a centrifugal operation, it is important to not only inexpensively configure a centrifuge including sample containers and a rotor but also increase the sample amount that can be centrifuged at one time to increase the amount of work done. To centrifuge a large amount of the liquid sample at one time, it is effective to increase the number of sample containers for use in the rotor and to increase the capacity of each sample container. However, to increase the capacity of the conventional cylindrical sample container, the outer diameter or the height of the body part 151 has to be increased. In that case, interference occurs between adjacent sample-container holding holes of the rotor, and therefore the arrangement positions of the holding holes have to be shifted away from the rotation center in a radial direction (to an outer circumferential side). As a result, the diameter of the rotor itself is increased to increase the mass, thereby degrading portability of the rotor by the operator and attachability to the centrifuge.
The increase in diameter of the rotor leads to an increase in air resistance (windage loss) at the time of high-speed rotation in the centrifuge. To address this, the output of a driving device of the centrifuge has to be increased, and the output of a cooling device part for cooling the rotor has to be increased. Moreover, with the increase of the diameter of the rotor, the size of the rotor chamber of the centrifuge has to be also increased, thereby posing problems of increasing the installation area of the centrifuge and increasing the price of the centrifuge. In the course of solving these problems, the inventors paid attention to the fact that a component portion of the rotor causing an increase in weight (hereinafter referred to as a “superfluous portion”) is present between adjacent sample-container holding holes when the rotor having cylindrically-shaped sample containers arranged therein is viewed from above, and tried an improvement of reducing this superfluous portion as much as possible. Furthermore, in the course of this improvement, the inventors found that a superfluous portion near the outer circumference of the rotor is a cause of increasing the mass of the rotor and a centrifugal load applied to this superfluous portion is a factor in decreasing the strength of the rotor.
The present invention has been made in view of the background described above, and a preferred aim of the present invention is to prevent a sample container for a centrifuge, having an increased sample amount that can be centrifuged at one time, from being broken or degraded due to a centrifugal force at the time of operation.
Another object of the present invention is to provide a sample container for a centrifuge having a body part and a circular lid part, the sample container provided with a neck support member which restricts movement and deformation of the lid part due to centrifugal force.
Still another object of the present invention is to provide a sample container for a centrifuge, the sample container which can prevent a neck support member from not being mounted, does not reduce its useful life, and is excellent in durability and usability.
The typical ones of the inventions disclosed in the present application will be briefly described as follows.
According to an embodiment of the present invention, a sample container for a centrifuge includes: a body part capable of accommodating a sample; an outer lid mountable on the body part; and a neck support member provided on an outer circumferential side of the outer lid for filling a space between an outer circumferential surface of the outer lid and a holding hole of a rotor of the centrifuge, the body part having a circular opening on top and the outer lid being attachable to and removable from the opening by screwing via a sealing member, the neck support member having an outer circumference substantially identical in shape to the body part when viewed from above, and the neck support member being arranged so as to be interposed between the outer lid and the body part when the outer lid is mounted on the body part.
According to another embodiment of the present invention, a sample container for a centrifuge includes: a body part capable of accommodating a sample; a lid part mountable on the body part; a neck support member provided on an outer circumferential side of the lid part for filling a space between an outer circumferential surface of the lid part and a holding hole of a rotor of the centrifuge, the body part having a non-circular outer shape when viewed from above and having a circular opening on top, the lid part being attachable to and removable from the opening by screwing via a sealing member, the neck support member having a non-circular outer shape identical to the shape of the body part when viewed from above, and the neck support member being arranged so as to be interposed between the outer lid and the body part when the outer lid is mounted on the body part.
According to the present invention, the outer circumference of the neck support member has a shape substantially identical to the shape of the body part when viewed from above and, the neck support member is arranged so as to be interposed between the outer lid and the body part when the outer lid is mounted on the body part. In this manner, the centrifugal force exerted on the outer lid can be effectively supported by the neck support member. Therefore, it is possible to prevent the sample container for the centrifuge from being broken or degraded due to the centrifugal force.
According to the present invention, the neck support member has a non-circular outer shape identical to the shape of the body part when viewed from above and, with the lid part mounted on the body part, the neck support member is interposed between the lid part and the body part. In this manner, the centrifugal force exerted on the lid part can be supported also by the support member. Therefore, it is possible to prevent the sample container for the centrifuge from being broken or degraded due to the centrifugal force.
The above and other preferred aims and novel characteristics of the present invention will be apparent from the description of the present specification and the accompanying drawings.
Hereinafter, a first embodiment of the present invention will be described based on the drawings. Note in the drawings described below that the same portions are provided with the same reference numeral, and repetitive descriptions will omitted. Also, it is assumed in the specification that vertical and horizontal directions of a centrifuge are those indicated in
The lower stage obtained by partitioning with the partition plate 2A inside the casing 2 is provided with a driving part 5, which is mounted on the partition plate 2A. The riving part 5 has a motor housing 6, and an electric motor 7 is provided inside the motor housing 6 as a driving source. The motor housing 6 is fixed to the partition plate 2A via a damper 8. A shaft case 6A is provided on an upper side of the motor housing 6, and is arranged inside the rotor chamber 4 as penetrating through a hole 3B provided on the bottom of the chamber 3. The motor 7 has a rotating shaft 7A arranged so as to penetrate through the inside of the shaft case 6A, extending upward to the inside of the rotor chamber 4. A fitting part 12 is provided at an upper end of the rotating shaft 7A. The fitting part 12 is set in a fitting hole 31A of the rotor 30. The rotor 30 is configured so as to be attachable to and removable from the fitting part (driving shaft part) 12, and the rotor 30 is rotated by the motor 7. Normally, an operator selects and mounts the rotor 30 having holding holes in accordance with sample containers 50 for use. In each sample-container holding hole 32 formed in the rotor 30, the sample container 50 filled with a sample (a liquid sample) is inserted.
The sample container 50 has a circular opening 51A at the top, and a cap part 52 is mounted on the opening 51A. The cap part 52 of the present embodiment is mainly configured of a lid part (an outer lid 53 and an inner lid 54) and a neck support member 70 attachable to and removable from the lid part. When the lid part (the outer lid 53) is screwed to the body part 51, the opening 51A is sealed. A feature of the present embodiment is that a distance L1 from a center line 35 in the vertical direction of the sample container 50 to a side wall on an inner circumferential side of the container in a perpendicular direction is significantly larger than a distance L2 from the center line 35 to a side wall on an outer circumferential side of the container (L1>L2). On the other hand, at the opening 51A, a distance C1 from the center line 35 to an inner side of the opening and a distance C2 from the center line 35 to an outer side thereof are equal (C1=C2). It is assumed that these distances L1, L2, C1, and C2 are measured from the center line 35 in the perpendicular direction. The center line 35 is a virtual line passing through the center position (or a barycenter) of a bottom surface of the sample container 50 and the center position of the outer lid 53 (or the center of the opening 51A), and the center line 35 and the upper surface of the outer lid 53 have a perpendicular positional relation.
The neck support member 70 is a member interposed to fill a space between the outer lid 53 and an outer circumferential side wall part 31D of the rotor body 31. When the neck support member 70 is interposed between the outer lid 53 and the outer circumferential side wall part 31D, the relatively heavy outer lid 53 can be inhibited from moving to outside by a centrifugal force, thereby effectively preventing an excessive force from acting on the opening 51A and a shoulder part 51D. In the present embodiment, the lid part is implemented by the outer lid 53 and the inner lid 54 to achieve excellent sealing performance. Between a flange part extending in a radial direction of the inner lid 54 and an upper-end annular plane of the opening 51A, an O-ring 57 as a sealing member is interposed, thereby more enhancing sealing performance. On an upper part of the outer lid 53, a plurality of through holes 53A for removal are formed so as to penetrate through a space portion formed by fixing a projection 54A of the inner lid 54 to the outer lid 53. With this shape, a space in the cap can be ensured between the outer lid 53 and the inner lid 54. This space is formed such that the nearer the center of the outer lid 53, the wider a gap between the outer lid 53 and the inner lid 54. As the inner lid 54, a member identical to the inner lid 154 (refer to
Next, the shape of the rotor body 31 will be described with reference to
The rotor body 31 has a hollow part (a thinned part) 31G formed by hollowing the center part in a downward direction to reduce the weight of the rotor body 31 at an upper part of the center axis and to lower the barycenter. At the center of the rotor body 31, a screw hole 31H for fixing the rotor cover 40 by screwing the handle 41 is formed. The rotor body 31 has an integral structure (a solid type) manufactured by machining with the use of an aluminum alloy or titanium alloy material. The rotor body 31 can be manufactured of a CFRP composite material also.
The body part 51 of the sample container 50 forms a container with a cross sectional shape of a curved surface based on an equilateral triangle having a large radius of curvature (for example, R=179 mm) with each of the side parts 56 of the equilateral triangle mildly projecting outward and with three apex parts 55 of the equilateral triangle connected with curved surfaces each having a small radius of curvature (for example, R=37 mm). On a side lower than the male thread part 51B of the body part 51, the shoulder parts 51D for smooth connection to the apex parts 55 and the side parts 56 are formed. The shoulder parts 51D each have a substantially triangular-shaped (a rice-ball-shaped) contour of its outer edge when viewed from above, and a circular contour of its inner circumferential edge. As such, the outer position of the body unit 51 is outside of the outer position of the opening 51A in a radial direction, and the shoulder parts 51D each connect the outer position of the body part 51 from the outer position of the opening 51A.
The body part 51 of the sample container 5, the neck support member 70, and the inner lid 54 are each preferably manufactured using a thermoplastic material (high-polymer resin) such as polypropylene or polycarbonate. The body part 51 can be easily manufactured by a blow molding method or an injection blow molding method. The opening 51A has an inner radius of 37.5 mm and an outer radius of 42.5 mm. The neck support member 70 can be easily manufactured by an injection molding method. In this manner, by forming with a thermoplastic material (high-polymer resin), a sample container highly resistant to chemicals and easy to handle can be achieved. Also, the O-ring 57 is suitably made of rubber, and a commercially-available product can be used. The body part 51 may be configured to be transparent or may be configured to be colored so that the inside is not viewable. On the other hand, it is important to configure the outer lid 53 with a non-elastic material. In the present embodiment, the outer lid 53 is integrally molded with a metal, for example, is manufactured of an aluminum alloy. In the present embodiment, the outer lid 53 has a weight of 260 g, the neck support member 70 has a weight of 92 g, the inner lid 54 has a weight of 32 g, and the body part 51 has a weight of 200 g. Here, the weight of the outer lid 53 is larger than the weight of the body part 51. In this manner, by making the outer lid 53 heavier than the body part 51, a centrifugal load can be effectively exerted in a direction of fastening the inner lid 54 by a downward centrifugal force exerted on the outer lid 53. Also, the neck support member 70 is far lighter than the outer lid 53, and has a weight that is half of the weight of the body part 51 or smaller. Therefore, the centrifugal load of the neck support member 70 can be effectively prevented from being excessively exerted on the body part 51. The neck support member 70 can effectively distribute centrifugal loads in the radial and axial directions locally exerted on a portion near the opening 51A and the male thread part 51B while reducing the load on the body part 51.
The neck support member 70 has a circular hollow hole formed for letting the cylindrical part 53C of the outer lid 53 penetrate through. This hollow hole has an inner circumferential part (an inner circumferential surface) 70A formed therein. The inner circumferential part 70A has an inner diameter to an extent that a minimum gap is formed between the inner circumferential part 70A and the cylindrical part 53C. In this manner, the outer lid 53 can freely rotate with respect to the neck support member 70. Projecting parts 70E globularly projecting inside in a radial direction are formed at a plurality of positions along the circumferential direction of the inner circumferential part 70A, for example, at three positions at 120-degree pitches. The projecting parts 70E are formed at the time of integral molding of the neck support member 70. The neck support member 70 has an upper surface flatly formed so as to correspond to the lower surface (the step portion) of the collar part 53B. On the other hand, the neck support member 70 has a lower surface similar to the outer contour shape of the body part 51.
The shape of the inner lid 54 has the same shape of the inner lid 154 of the conventional example. The projection 54A is formed projecting upward near the center part of the inner lid 54. On the outer circumferential side of the inner lid 54, a cylindrical part 54C linked to an edge part 54B and therebelow is formed. The O-ring 57 is interposed so as to abut on an outer circumferential side of the cylindrical part 54C and a lower surface of the edge part 54B.
Next, the shape of the neck support member 70 alone will be described with reference to
Effects of the respective components of the cap part 52 described so far are described. In the centrifuge 1, the rotor 30 rotates at a high speed, and a large centrifugal load is exerted on the cap part 52. In the centrifuge 1 of the present embodiment, the outer circumference of the outer lid 53 and the outer circumferential side wall part 31D of the rotor body 31 are separated away from each other and, furthermore, a portion for holding the outer circumferential side of the outer lid 53 is not present. Therefore, a portion near the opening 51A of the body part 51 and the shoulder parts 51D may be broken by the centrifugal load of the cap part 52. This phenomenon cannot occur in the case of the conventional cylindrical sample container 150 illustrated in
Next, effects of the collar part 53B of the outer lid 53 will be described. As illustrated in
Next, effects brought by the collar part 53B will also be described. As indicated by bold arrows in
As described above, in the sample container 50 with the non-cylindrical outer shape, the neck support member 70 is an important component. However, since the neck support member 70 is configured of a component different from the outer lid 53 and the body part 51, the operator may possibly start operation of the centrifuge 1 forgetting about mounting the neck support member 70. To prevent this, the neck support member 70 has to be configured such that it is difficult to forget about mounting the neck support member 70. For example, ideally, the outer lid 53 and the neck support member 70 are configured to be integrally molded to be relatively fixed to each other. However, the shapes of the shoulder parts of the body part 51 are not rotationally symmetrical to each other, the cap part 52 and the body part 51 cannot be fastened by being screwed. This is because the space between the outer lid 53 and the outer circumferential side wall part 31D of the rotor body 31 is not in an axially symmetric shape. For this reason, a gap may occur between the outer shape of the cap part 52 and the outer shape of the body part 51 depending on the fastening condition, and the cap part 52 and the body part 51 may interfere with each other before fastening is completed. Therefore, the outer lid 53 and the neck support member 70 have to be mutually not fixed to each other, while having the structure preventing the neck support member 70 from being forgotten to be mounted. The following structure has been invented by the inventors to solve this problem.
Before the cap unit 52 is mounted on the body part 51, the neck support member 70 is engaged with the outer lid 53 so as to be capable of relative rotation. Here, since the outer circumferential part of the cylindrical part 53C of the outer lid 53 and the projecting parts 70E of the neck support member 70 projecting inside slightly interfere with each other, the neck support member 70 is forcibly fitted by using a method such as press fitting. In this manner, the projecting parts 70E are engaged as being inserted in the groove part 53D formed on the cap part 52. The degree of interference between the cylindrical part 53C and the projecting parts 70E is arbitrarily determined depending on the shape and dimensions of the projecting parts 70E at the time of manufacture. The projecting parts 70E of the neck support member 70 may be arranged at any positions as long as they do not interfere with the groove part 53D at the time of completion of engagement, and the shape, dimensions, and the number of projecting parts 70E of the neck support member 70 may be optional as long as no interference occurs. Since the groove part 53D is continuously provided so as to be axially symmetrical with respect to the center axis of the outer lid 53, the outer lid 53 and the neck support member 70 can mutually slide freely in the circumferential direction.
If the outer lid 53 and the neck support member 70 are engaged with each other before the outer lid 53 is mounted in the body part 51, they are not separated unless the operator intends to do so. Therefore, the neck support member 70 is not forgotten to be mounted when the centrifuge is operated. On the other hand, if the outer lid 53 and the neck support member 70 have to be separated for the purpose of cleaning, replacement, or others, they can be forcibly separated from each other by a procedure obtained by reversing an assembling procedure.
The cap part 52 having the outer lid 53 and the neck support member 70 is inserted in the body part 51 with a screw structure. Here, the shoulder parts 51D of the body part 51 and the recessed curved surface part 70D of the neck support member 70 have to coincide with each other at the time of mounting. Since the sample container 50 has a substantially triangular outer shape, the shoulder parts 51D can take contours axially asymmetrical to the center axis of the body part 51. When the recessed curved surface part 70D is made to coincide with the shoulder parts 51D, the neck support member 70 is inevitably fixed to the body part 51 in the circumferential direction. Here, since the outer lid 53 and the neck support member 70 can mutually slide freely in the circumferential direction, even if the neck support member 70 is relatively fixed to the body part 51, no problem occurs to attachment and removal of the outer lid 53 by screwing.
While description has been made based on the first embodiment of the present invention, various modifications can be made. For example, while the lid part has been manufactured so as to have a double structure of an outer lid and an inner lid, the lid part may be manufactured as an integral lid part. Also, while the present invention is particularly effective when the shape of the sample container is not cylindrical, the shape of the outer contour of the sample container when viewed from above is not restricted to a substantially triangular shape, and the present invention can be similarly used to another non-circular container (however, its opening has a circular shape). Furthermore, even if the sample container has an existing cylindrical shape, the present invention can be similarly used if the outer shape of the lid part and the outer shape of the body part are different from each other in the container.
Next, a second embodiment of the present invention will be described with reference to
The neck support member 270 has a circular hollow hole formed for letting the cylindrical part 53C of the outer lid 53 penetrate through. A counter part of the hollow hole serves as an inner circumferential part 270A. The inner circumferential part 270A has an inner diameter so that a minimum gap is formed between the inner circumferential part 270A and the cylindrical part 53C, and the neck support member 270 can be attached to and removed from the cylindrical part 53C. Projecting parts 270E semispherically projecting inside in a radial direction are formed at a plurality of positions of the inner circumferential part 270A, for example, at three positions at 120-degree pitches. This is to reuse the outer lid 53 of the first embodiment. If the outer lid 53 of the first embodiment is not reused and a cap part for the body part 251 is manufactured, a mounting method may be taken in which the neck support member 270 is firmly fixed so as not to be able to make relative rotation with respect to the outer lid 53. Also, by utilizing the fact that relative rotation is unnecessary at the time of mounting, the outer lid and the neck support member may be configured by integral molding of a light metal such as titanium or resin. The projecting parts 270E are formed at the time of integral molding of the neck support member 270, are arranged so as to be engaged without interference with the groove part 53D continuous in the circumferential direction and formed on the outer circumferential surface of the outer lid 53. The neck support member 270 has an upper surface flatly formed so as to correspond to the lower surface (the step portion) of the collar part 53B. As such, the neck support member 270 is held so as not to fall downward with respect to the outer lid 53, and is coupled in the circumferential direction so that the neck support member 270 and the outer lid 53 can relatively rotate. The neck support member 270 has a lower surface similar to the outer contour shape of the body part 251 and, in particular, is formed so as to be in good contact with the shoulder parts 251D. The outer circumferential surface 270B of the neck support member 270 has a circular outer shape and a circular inner shape of a section perpendicular to the center line (a reference numeral 235 of
The body part 251 of the sample container 250 forms a container having a circular cross sectional shape and, as with the sample container 150 illustrated in
In the same manner as the first embodiment, the body part 251 of the sample container 250, the neck support member 270, and the inner lid 54 are each preferably manufactured of a thermoplastic material such as polypropylene or polycarbonate. As such, the outer lid 53 is configured of a member with a large specific gravity in weight, the neck support member 270 is configured of a member with a small weight, and the cap part 252 is mainly configured of two components with different weights. Therefore, the cap part 252 in the sample container having a relatively large capacity of 500 ml or larger can be relatively light in weight. According to calculations by the inventors, it has been found that when a 230-ml-capacity and metal-cap-equipped sample container for a high-speed rotor of a category different from the model covered by the present invention is increased in shape to scale up the capacity to 1000 ml, the weight of the cap part is increased from 96 g to an impractical weight, that is 460 g. However, if only the outer lid 53 is made of a metal and the neck support member 270 is resinified as in the present embodiment, the entire weight except for the inner lid 54, that is, the total mass of the outer lid 53 and the neck support member 270, is 360 g, which is light and under 400 g. In this manner, in the second embodiment, while an increase in weight of the cap part is effectively prevented, an excessive centrifugal load can be prevented from being exerted on the opening 251A by interposing the neck support member 270. Therefore, a further increase in capacity of the sample container than ever and an increase in rotation of the rotor can be achieved.
Next, the shape of the neck support member 270 alone will be described with reference to
When the rotor body 231 rotates at a high speed, a centrifugal load is exerted on the cap part 252. Since the neck support member 270 for supporting the outer circumference of the outer lid 53 is added to the outer lid 53 of the present embodiment, the cap part 252 can be prevented from being displaced to a centrifugal force direction. This effect is illustrated in
However, in the present embodiment, the collar part 53B is formed on the outer circumferential part of the outer lid 53 and, when the axially downward force 282 becomes strong, the lower flat surface portion (the annular flat part) of the collar part 53B can be in contact with an upper surface 270C of the neck support member 270 (refer to
During centrifugal operation, as indicated by bold arrows in the drawing, a fluid pressure is loaded on the body part 251 from inside toward outside. A liquid level 260A of a sample 260 in the sample container 250 becomes extending in the vertical direction (parallel to a rotating axis) due to the centrifugal force 281. Near the shoulder part 251D of the body part 251, a strong fluid pressure is applied from inside toward outside as indicated by arrows 283A to 283C. This is due to the sample 260 during centrifugal operation, and a stronger fluid pressure is exerted on a portion with a larger radius of gyration. A particularly strong fluid pressure is exerted on the shoulder part 251D positioned outside during centrifugal operation. As indicated by the arrows 283A to 283C, the body part 251 may be expanded upward by an axially upward force. While this deformation can be inhibited to some extent by pressing the shoulder part 251D axially downward by the neck support member 270, the axially downward force 282 due to the centrifugal force of the outer lid 53 described above is added to the neck support member 270 via the collar part 53B, and therefore this can further reliably prevent deformation of the shoulder part 251D.
As described in the foregoing, according to the second embodiment, only by replacing the neck support member 70 used in the first embodiment by the neck support member 270 for the cylindrically-shaped body part 251, the neck support member 270 can be used as the cap part 252 for the body part 251. Here, since the inner lid 54 and the O-ring 57 of the first embodiment can be used as they are, shared components can be increased to reduce manufacturing cost. Also, since the neck support member 270 is made attachable to and removable from the outer lid 53, the cap part 252 can be easily cleaned. Furthermore, while the cap part is formed of the outer lid formed of a material with a large specific gravity and the neck support member formed of a material with a small specific gravity in the first and second embodiments, they can be manufactured by integral molding when the body part 251 is a cylindrically-shaped bottle. However, if the neck support member 270 and the outer lid 53 are both made of a metal to increase the capacity to 500 ml or more, the weight of the entire cap part is too heavy compared with the size of the body part 251 and the opening 251A, and therefore the axially downward force 282 exerted on the body part 251 becomes too excessive. Moreover, since the weight of the entire sample container 250 becomes heavy, the load on a rotor body 231 side is increased, which is not preferable. Therefore, when the outer lid and the neck support member are integrally configured, the present invention is preferably restricted to be applied to a sample container with a small capacity smaller than 500 ml or/and a sample container for a low-speed rotor with a maximum permissive number of revolution equal to or smaller than 10000 rpm.
While the present invention has been described above based on the embodiments, the present invention is not restricted by the embodiments described above, and can be variously modified within a range not deviating from the gist of the present invention. For example, while the body parts 51 and 251 are made of a synthetic resin in the first and second embodiments, the body part may be made of a metal.
Hereinafter, sample containers for centrifuges of embodiments and effects obtained from each embodiment will be described.
In a sample container for a centrifuge of an embodiment, the outer circumference of the neck support member is has a shape substantially identical to the body part when viewed from above. When the outer lid is mounted on the body part, the neck support member is arranged so as to be interposed between the outer lid and the body part. Thus, the centrifugal force exerted on the outer lid can be effectively supported by the neck support member. Therefore, the sample container for the centrifuge can be prevented from being broken or degraded due to a centrifugal force.
In a sample container for a centrifuge of another embodiment, the outer lid has an outer circumference having a collar part, and the neck support member is interposed between the collar part and the body part. Thus, by only fastening the lid part, the neck support member can also be appropriately positioned in a good condition. By the collar part, the neck support member can be pressed.
In a sample container for a centrifuge of still another embodiment, the neck support member has a smaller specific gravity and a lighter weight compared with the outer lid. Thus, an influence of a centrifugal load on the body part due to installation of the neck support member can be reduced.
In a sample container for a centrifuge of still another embodiment, the neck support member has a non-circular outer shape identical to the shape of the body part when viewed from above. By mounting the lid part on the body part, the neck support member is interposed between the lid part and the body part. Thus, the centrifugal force exerted on the lid part can be supported also by the support part. Therefore, the sample container for the centrifuge can be prevented from being broken or degraded due to a centrifugal force.
In a sample container for a centrifuge of still another embodiment, the neck support member is interposed between the shoulder part and the lid part in the axial direction. Thus, a local load exerted on the opening from the lid part can be reduced.
In a sample container for a centrifuge of still another embodiment, the neck support member has a lower surface in the axial direction having a shape corresponding to the shoulder part, and has an upper surface in the axial direction formed in a flat shape perpendicular to the axial direction. Thus, the neck support member can be prevented from being broken due to a local load exerted on a partial portion of the neck support member.
In a sample container for a centrifuge of still another embodiment, the lid part has a flat surface part which abuts on the upper surface of the neck support member. Thus, the lid part and the body part can be freely attached and removed by a screw structure.
In a sample container for a centrifuge of still another embodiment, the neck support member is held by the lower surface of the step part provided on the lid part and the shoulder part. Thus, only by fastening the lid part, the neck support member can also be appropriately positioned in a good condition.
In a sample container for a centrifuge of still another embodiment, the step part is formed of a collar part projecting in a radial direction from an outer circumferential surface of the lid part. Thus, the collar part can form a holding part to be held by the operator, and also can form the step part for fixing the neck support member. Here, the step part is formed at an upper position than the center of the axial direction of the lid part. Thus, the gap between the lid part and the holding hole of the rotor can be filled at a half or more of the distance of the lid part in the axial direction, and an excellent support effect can be expected.
In a sample container for a centrifuge of still another embodiment, the lid is manufactured by integral molding of a metal. Thus, high strength and high durability can be achieved.
In a sample container for a centrifuge of still another embodiment, the lid part is heavier than plastic or others. Thus, at the time of centrifugal operation, with a centrifugal force, the lid part can have a pressing force with respect to the body part, and therefore deformation of the shoulder part can be reliably prevented via the neck support member.
In a sample container for a centrifuge of still another embodiment, the neck support member is engaged with and attachable to and removable from the lid part and is held so as to be able to relatively rotate with respect to the lid part. Thus, the lid part can be fastened with the neck support member mounted on the lid part. Therefore, a sample container that is easy to use can be achieved.
In a sample container for a centrifuge of still another embodiment, the lid part and the neck support member are held by the groove part extending in a circumferential direction and the projection. Thus, once assembled, they are not removed unless the operator intends to do so. For this reason, no concern is required about whether the neck support member is mounted, and the opening and its periphery of the sample container for the centrifuge can be prevented from being deformed or broken due to the centrifugal force.
In a sample container for a centrifuge of still another embodiment, the groove part is continuously formed in the circumferential direction. Thus, even if the neck support member engaged with the groove part is fixed in the circumferential direction, the lid part can be freely slid in the circumferential direction. Therefore, the lid part and the body part can be freely attached and removed by a screw structure.
Instill another embodiment, the rotor for the centrifuge has a plurality of holding holes for holding the sample containers for the centrifuge described above, and the centrifuge has a driving part for rotating this rotor for the centrifuge and a rotor chamber which accommodates the rotor. Therefore, it is possible to achieve a rotor for a centrifuge and a centrifuge capable of attaining more resistance to a centrifugal load than ever, a large capacity more than 1000 ml, and higher speed than those of conventional models.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2012-117322 | May 2012 | JP | national |
| 2013-085703 | Apr 2013 | JP | national |
