JP2009240978A - Centrifugal separator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifugal separator capable of automatically and properly setting airflow of air for cooling a rotor. <P>SOLUTION: A valve mechanism 32 is so installed as to cover an air suction port 3a in the upper side of a door 3. The valve mechanism 32 includes a first spring 32A, which is a compression spring, fixed in the top face of the door 3 and a first plate 32B connected to the upper end of the first spring 32A. When air flows in through the air suction port 3a, the first plate 32B moves downward and the first spring 32A is compressed. Consequently, the aperture surface area in the air suction port 3a is reduced. That is, the aperture surface area in the air suction port 3a is automatically reduced due to flowing-in of air. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a centrifuge, and more particularly, to an air-cooled centrifuge that cools a rotor by a flow of air.

  A conventional centrifuge includes a frame that constitutes an outer frame and has an upper end opening, a door that opens and closes the upper end opening, a bowl that is supported by the frame to define a rotor chamber, and a rotor that is mounted in the rotor chamber. It mainly includes a rotating shaft that rotates and a motor that drives the rotating shaft to rotate. When the rotor rotates, the rotor generates heat due to friction between the rotor surface and the air in the rotor chamber. In order to suppress this heat generation, an intake port is formed in the door, an exhaust port is formed in the frame, air is taken in from the intake port by rotation of the rotor, and discharged from the exhaust port, thereby suppressing the heat generation of the rotor. (For example, refer to Patent Document 1).

There is also a centrifuge in which a pair of holes are formed in the door, and a disc in which a plurality of holes of different sizes are formed is rotatably attached so as to cover the pair of holes. The user manually rotates the disk so that the hole of the disk and the hole of the door face each other, thereby taking in a necessary amount of air and suppressing the heat generation of the rotor (for example, see Patent Document 2). .
JP 2007-90152 A Japanese Utility Model Publication No. 2-37760

  However, in the centrifuge of Patent Document 1, air is taken in more than necessary, and the noise felt by the user becomes very large, making the user uncomfortable. Moreover, in the centrifuge of patent document 2, since the user needed to set the air volume which cools a rotor by rotating a disk manually, operativity was bad. In addition, since the user does not know the appropriate air volume for cooling the rotor, the air volume may be more than necessary, or conversely, there may be less noise than necessary. Sometimes it could not be cooled.

  Accordingly, an object of the present invention is to provide a centrifuge capable of automatically and appropriately setting the air volume for cooling the rotor.

  In order to achieve the above object, the present invention comprises an outer frame, a frame having an upper end opening and having an exhaust port formed therein, a lid body which opens and closes the upper end opening and has an air intake port formed thereon, A bowl disposed in the frame and fixedly supported by the frame, defining a rotor chamber together with the lid, a rotating shaft extending into the ball and mounting the rotor to rotate the rotor in the rotor chamber; A motor that is supported by a frame and that rotationally drives the rotating shaft, and air is introduced into the rotor chamber from the air inlet through the upper end opening due to a pressure difference caused by rotation of the rotor. In the centrifugal separator in which an air passage for cooling and discharging the air from the exhaust port is defined, the air passage is provided with a valve mechanism for automatically changing an opening area of the air passage. Offering a machine.

  According to such a configuration, the opening area of the air passage is automatically changed according to the pressure difference by the valve mechanism, so that only a necessary amount of air can flow into the rotor chamber. Therefore, the rotor can be appropriately cooled, and the noise felt by the user can be reduced. Further, since the opening area is automatically changed and only a necessary amount of air flows, the operability of the centrifuge by the user can be improved.

  Here, it is preferable that various rotors can be selectively mounted on the rotating shaft, and the valve mechanism changes the flow path area according to the types of the various rotors.

  According to such a configuration, the opening area is automatically changed according to the type of the rotor, so that an appropriate amount of air according to the type of the rotor can be introduced. Therefore, the operability of the centrifuge by the user can be improved.

  The rotor further includes a rotor main body including a sample mounting portion, and a rotor cover that covers the sample mounting portion and can be attached to and detached from the rotor main body, and the flow path area depends on the presence or absence of the rotor cover. It is preferable to change.

  According to such a configuration, since the opening area is automatically changed according to the presence or absence of the rotor cover, an appropriate amount of air according to the presence or absence of the rotor cover can be introduced. Therefore, the operability of the centrifuge by the user can be improved.

  Moreover, it is preferable to provide the cover detection sensor provided in this cover body and detecting the presence or absence of this rotor cover.

  According to this configuration, the presence or absence of the rotor cover can be detected by the cover detection sensor.

  Further, it is preferable that the rotation speed of the motor can be changed, and the flow path area changes according to the rotation speed of the rotor.

  According to such a configuration, the opening area is automatically changed according to the rotational speed of the rotor, so that an appropriate amount of air according to the rotational speed of the rotor can be introduced. Therefore, the operability of the centrifuge by the user can be improved.

  According to the centrifuge of the present invention, the air volume for cooling the rotor can be automatically and appropriately set.

  A centrifuge according to a first embodiment of the present invention will be described with reference to FIGS. In the following description, the direction shown in FIG. 1 is the front-rear direction of the centrifuge.

  As shown in FIG. 1, the centrifuge 1 includes a frame 2 and a door 3. The door 3 and the frame 2 constitute an outer frame of the centrifuge 1 and have a box shape having an upper end opening 2a. A door packing 21, which is an elastic body, is disposed around the upper end opening 2 a of the frame 2. An operation panel 22 having operation buttons, a display unit, and the like is provided on the front surface of the frame 2. An exhaust port 2 b is formed on the rear surface side of the frame 2.

  The door 3 is provided at the upper end and the rear side of the frame 2 so as to be opened and closed by a hinge portion 31. The door 3 is formed with an air inlet 3a. A valve mechanism 32 is disposed on the upper side of the door 3 so as to cover the intake port 3a. The valve mechanism 32 includes a first spring 32A that is a compression spring fixed to the upper surface of the door 3, and a first plate 32B connected to the upper end of the first spring 32A. The spring constant of the first spring 32A is designed based on the shape and the rotational speed of the rotor 6 so that the opening area (flow path area) by the air inlet 3a and the first plate 32B is an appropriate opening area. That is, the spring constant of the first spring 32A is such that the amount of air flowing in from the air inlet 3a is appropriate when the opening area is reduced by the movement of the first plate 32B and the compression of the first spring 32A when air flows in, which will be described later. Designed to be a quantity.

  Next, the internal structure of the centrifuge 1 will be described. A damper 4 is provided on the bottom surface of the frame 2 and supports the motor 5. The motor 5 has a rotating shaft 5A for outputting the driving force. The rotating shaft 5A extends upward, and a rotor 6 for separating the sample to be separated from the sample is connected to the upper end of the rotating shaft 5A and can rotate together with the rotating shaft 5A. As shown in FIGS. 2 and 3, the rotor 6 that is an angle rotor includes a rotor body 6A having a sample mounting portion 62 for mounting a tube 61 into which a sample is injected, and a rotor cover that can be attached to and detached from the rotor body 6A. 6B. In FIG. 1, the rotor 6 with the rotor cover 6B attached is shown, and the centrifuge 1 can rotate the rotor 6 with or without the rotor cover 6B attached.

  As shown in FIG. 1, a bowl packing 7 is provided on the upper surface of the motor 5 and around the rotating shaft 5A. On the upper side of the bowl packing 7, a bowl 8 that defines the rotor chamber 8 a together with the door 3 is disposed. The bowl 8 has a bottomed cylindrical shape, and a rotation shaft insertion hole 8b for inserting the rotation shaft 5A is formed at the bottom thereof. An annular first opening 8 c is formed between the bowl 8 and the upper end of the frame 2. The rotor 6 is located in the rotor chamber 8a. In addition, a partition plate 9 that divides the space in the frame 2 into an upper side and a lower side is fixed to the frame 2. The partition plate 9 is configured integrally with the bottom of the bowl 8. The partition plate 9 is formed with two second openings 9a that communicate the upper space and the lower space in the frame 2 (see also FIG. 8). Further, a protector 10 (FIG. 8) that defines an annular space together with the bowl 8 is provided in the frame 2. The first opening 8c and the second opening 9a define an air path (arrows A1 to A9) from the intake port 3a to the exhaust port 2b.

  Next, the operation of the centrifuge 1 will be described. By pressing a start switch (not shown), the driving of the motor 5 is started. The rotating shaft 5 </ b> A is rotated by driving the motor 5, and with this rotation, the rotor 6 is also rotated and the sample to be separated is separated from the sample in the rotor 6. At this time, the motor 5 vibrates, but the vibration is reduced by the damper 4. Further, the rotor 6 generates heat due to friction with the air due to the rotation of the rotor 6.

  Next, the air flow during operation of the centrifuge 1 will be described with reference to FIG. When the rotor 6 rotates, the pressure near the outer periphery of the rotor 6 increases, and conversely, the pressure decreases near the rotation center. That is, a pressure difference is generated due to the rotation of the rotor 6. Therefore, the vicinity of the intake port 3a in the rotor chamber 8a is negative. Thereby, the air outside the door 3 passes through the valve mechanism 32 and the intake port 3a and is sucked into the rotor chamber 8a (arrow A1). Then, the air (arrow A1) sucked from the intake port 3a flows around the rotor 6 (arrows A2 to A5) in the rotor chamber 8a to cool the rotor 6. Thereby, the rotor 6 whose temperature has been increased by the rotation is cooled. Thereafter, the air that has cooled the rotor 6 passes through the first opening 8c and the second opening 9a (arrows A6 and A7), flows to the lower side of the partition plate 9 (arrow A8), and then goes to the outside from the exhaust port 2b. It is discharged (arrow A9).

  As described above, when air flows from the air inlet 3a, the first plate 32B moves downward, and the first spring 32A is compressed. Thereby, the opening area of the air path in the inlet port 3a decreases. That is, due to the inflow of air, the opening area (flow path area) of the air passage in the intake port 3a automatically decreases. Therefore, the inflow of air is suppressed and only a necessary amount of air can be introduced. Therefore, the rotor 6 can be appropriately cooled and the noise felt by the user can be reduced. Moreover, since the opening area in the inlet 3a reduces automatically and a required amount of air flows in, the operativity of the centrifuge 1 by a user can be improved.

  FIG. 4 shows a state in which the centrifuge 1 is operated using the rotor 6 with the rotor cover 6B removed. When the rotor 6 is rotated in this state, the rotor 6 with the rotor cover 6B removed has more irregularities on the surface. Therefore, the rotor 6 is compared with the case where the rotor 6 is rotated with the rotor cover 6B attached. The pressure difference due to the rotation of becomes large. Therefore, the negative pressure near the intake port 3a in the rotor chamber 8a also increases. Thereby, compared with the case where the rotor cover 6B of FIG. 1 is mounted, the first plate 32B moves further downward, the first spring 32A is further compressed, and the opening area of the air passage in the intake port 3a is also larger. Decrease. Accordingly, the same effect as that obtained when the rotor cover 6B of FIG. 1 is mounted can be obtained.

  Further, according to the valve mechanism 32 including the first spring 32A and the first plate 32B of the present embodiment, even if the pressure difference due to the rotation of the rotor 6 changes, the intake air is automatically taken in accordance with the change. The opening area at the mouth 3a can be changed. Therefore, an appropriate amount of air can be introduced to cool the rotor 6 and the operability of the centrifuge 1 by the user can be improved.

  Next, a centrifuge 101 according to a second embodiment of the present invention will be described with reference to FIG. The same members as those in the centrifuge 1 according to the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions will be described.

  As shown in FIG. 5, a valve mechanism 132 composed of a second spring 132A and a second plate 132B is provided on the partition plate 9 so as to cover each second opening 9a. In the valve mechanism 132, when air flows into the lower space of the frame 2 from the second opening 9a (arrow A17), the second plate 132B moves downward, and the second spring 132A is compressed. . Thereby, the opening area (flow path area) of the air path in the 2nd opening part 9a reduces. That is, the opening area in the second opening 9a is automatically reduced by the inflow of air. Therefore, the flow of air from the second opening 9a to the lower space of the frame 2 is suppressed, and consequently the amount of air flowing from the intake port 3a is also suppressed. Therefore, the centrifuge 101 including the valve mechanism 132 of the present embodiment also has the same effect as the centrifuge 1 of the first embodiment.

  Next, a centrifuge 201 according to a third embodiment of the present invention will be described with reference to FIGS. The same members as those in the centrifuge 1 according to the first embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions will be described.

  As shown in FIG. 6, the door 203 in the present embodiment includes a door base 233, a door upper plate 234, and a door inner plate 235, and forms a double structure. Three intake ports 203a are formed in a front portion of the door base 233 (FIG. 7), and a door opening 203b is formed in a portion facing the rotor chamber 8a. A first gap 203 c is formed between the door base 233 and the door inner plate 235, and a second gap 203 d is formed between the door inner plate 235 and the door upper plate 234.

  A valve mechanism 232 is provided in the door 203 and between the intake port 203a and the door opening 203b. The valve mechanism 232 includes a small motor 232A disposed in the second gap 203d and a plate-like valve 232B disposed in the first gap 203c. The small motor 232A includes an output shaft 232C connected to the valve 232B. The driving force of the small motor 232A is transmitted to the valve 232B via the output shaft 232C, and the valve 232B rotates.

  A portion of the door base 233 that faces the rotor chamber 8a is provided with a rotor cover detection sensor 41 that detects whether or not the rotor cover 6B of the rotor 6 is mounted. Further, in the rotor chamber 8 a and below the rotor 6, a rotor ID sensor 42 that determines the type of the rotor and a rotational speed sensor 43 that detects the rotational speed of the rotor 6 are provided. A control unit 44 that controls the motor 5, the small motor 232 </ b> A, and the like is disposed in the front portion of the frame 2. Based on the detection results of the rotor cover detection sensor 41, the rotor ID sensor 42, and the rotation speed sensor 43, the control unit 44 controls the small motor 232A and the rotation of the valve 232B.

  Next, the air flow during the operation of the centrifuge 201 in the present embodiment will be described with reference to FIGS. As in the first embodiment, due to the pressure difference caused by the rotation of the rotor 6 (in the direction of arrow B in FIG. 8), the air outside the door 203 passes through the intake port 203a, the first gap 203c, and the door opening 203b. Then, it is sucked into the rotor chamber 8a (arrows A11, A12, A1). The sucked air cools the rotor 6 (arrows A2 to A5), passes through the first opening 8c and the second opening 9a (arrows A6 and A7), and flows to the lower side of the partition plate 9 ( An arrow A8) is discharged from the exhaust port 2b to the outside (arrow A9).

  In the present embodiment, the valve mechanism 232 controls the amount of air flowing into the rotor chamber 8a by controlling the opening area (flow channel area) of the air passage. Specifically, the opening area is controlled by automatically rotating the valve 232B based on the presence / absence of a cover, the type of rotor, and the rotational speed of the rotor.

  A method for controlling the opening area will be described below. In the centrifuge 201 shown in FIG. 6, the rotor ID sensor 42 detects that the rotor 6 is a specific angle rotor among a plurality of rotors 6, and the rotor cover detection sensor 41 detects that the rotor cover 6B is mounted. When the rotational speed sensor 43 detects that the rotational speed of the rotor 6 is high (for example, 15,000 rpm), the valve 232B is automatically shown in FIG. 9 by the control unit 44 and the small motor 232A. It is turned to the state. In general, in the case of an angle rotor that rotates at high speed, since the outer appearance of the rotor is less uneven, a negative pressure in the vicinity of the door opening 203b cannot be obtained. However, since the rotor rotates at a high speed, the amount of heat generated by the friction between the rotor surface and air increases. Therefore, by rotating the valve 232B to the state shown in FIG. 9, the opening area of the air passage is increased, and a large amount of air can be sucked into the rotor chamber 8a. Thereby, it is possible to secure an air volume necessary for cooling the rotor 6 that becomes high temperature by high-speed rotation.

  On the other hand, the rotor ID sensor 42 detects that the rotor is a specific swing rotor (swing rotor 206 as shown in FIG. 11) among a plurality of rotors, and the rotational speed of the swing rotor 206 is low (for example, 3,000 rpm). When the rotational speed sensor 43 detects that the valve 232B is automatically rotated to the state shown in FIG. 10 by the controller 44 and the small motor 232A. In general, in the case of a swing rotor that rotates at a low speed, a negative pressure in the vicinity of the door opening 203b is sufficiently obtained due to the unevenness of the outer shape of the rotor, and the amount of air sucked becomes large. However, since the rotor rotates at a low speed, the amount of heat generated by friction between the rotor surface and air is not so high. Therefore, by rotating the valve 232B to the state shown in FIG. 10, the opening area of the air passage is reduced, and the amount of air flowing into the rotor chamber 8a can be suppressed. Therefore, it is possible to secure only the air volume necessary for cooling the swing rotor 206 that rotates at a low speed that does not reach a higher temperature than the angle rotor that rotates at a high speed, and it is possible to reduce the noise felt by the user.

  An example of the relationship between the rotational speed of the rotor 6 and the required opening area is shown in FIG. As shown in FIG. 12, the higher the rotation speed, the higher the temperature of the rotor 6, and the larger the opening area for taking in air necessary for cooling the rotor 6.

  As described above, according to the centrifuge 201 of the present embodiment, the opening area of the air passage can be changed by automatically rotating the valve 232B based on the detection results of the sensors 41 to 43. it can. Therefore, only the air volume necessary for cooling the rotor can be caused to flow into the rotor chamber 8a according to the type of rotor, the presence or absence of the rotor cover, and the rotational speed of the rotor. Therefore, the rotor can be appropriately cooled, and the noise felt by the user can be reduced. Moreover, since the required amount of air is allowed to flow by automatically changing the opening area of the air passage, the operability of the centrifuge 201 by the user can be improved.

  Next, a centrifuge 301 according to a fourth embodiment of the present invention will be described with reference to FIGS. The same members as those of the centrifuge 201 of the third embodiment are denoted by the same reference numerals, description thereof is omitted, and only different portions will be described.

  As shown in FIG. 13, the door 303 in the present embodiment includes a door base 333 and a door upper plate 334, and forms a layer structure. A door opening 303a is formed in the door base 333. A third gap 303 b is formed between the door base 333 and the door upper plate 334. The intake port has the same configuration as the intake port 203a shown in FIG.

  A valve mechanism 332 is provided at a portion of the door upper plate 334 facing the door opening 303a. The valve mechanism 332 includes a small motor 332A, a gear 332B, a rack gear 332C, and a valve 332D. The small motor 332A includes an output shaft 332E connected to the gear 332B. The gear 332B and the rack gear 332C are screwed together. The valve 332D is attached to the lower end of the rack gear 332C, and is located in the third gap 303b. The driving force of the small motor 332A is transmitted to the valve 332D via the output shaft 332E, the gear 332B, and the rack gear 332C, and the valve 332D moves up and down.

  According to the centrifuge 301 of the present embodiment, similarly to the centrifuge 201 of the third embodiment, as shown in FIGS. 13 and 14, based on the detection results of the sensors 41 to 43, The valve 332D can be automatically moved up and down to change the opening area (flow path area) of the air passage. Therefore, the centrifuge 301 of the present embodiment also has the same effect as the centrifuge 201 of the third embodiment.

  In addition, the centrifuge of this invention is not limited to embodiment mentioned above, A various deformation | transformation and improvement are possible in the range described in the claim. For example, like the centrifugal separator 401 shown in FIG. 15, a valve mechanism 432 including a third spring 432A that is a tension spring and a third plate 432B connected to the lower end of the third spring 432A is used as the rotor of the door 3. You may provide in the chamber 8a side. Even with this configuration, the same effect as the centrifuge 1 of the first embodiment can be obtained.

  In this embodiment, the valve mechanism is controlled according to the rotational speed detected from the rotational speed sensor 43, but the valve mechanisms 232 and 332 are controlled based on the set rotational speed input from the operation panel 22. May be.

Sectional drawing of the centrifuge in the 1st Embodiment of this invention. The external appearance perspective view which shows the state which mounted | wore the rotor cover of the rotor of the centrifuge in embodiment of this invention. The external appearance perspective view which shows the state which removed the rotor cover of the rotor of the centrifuge in embodiment of this invention. Sectional drawing which shows a state when the rotor cover in the 1st Embodiment of this invention is removed and a centrifuge is operated. Sectional drawing of the centrifuge in the 2nd Embodiment of this invention. Sectional drawing of the centrifuge in the 3rd Embodiment of this invention. Sectional drawing along the VII-VII line of FIG. Sectional drawing along the VIII-VIII line of FIG. The figure which shows the state which rotated the valve of the centrifuge in the 3rd Embodiment of this invention, and enlarged the opening area of the air path. The figure which shows the state which rotated the valve of the centrifuge in the 3rd Embodiment of this invention, and narrowed the opening area of the air path. 1 is an external perspective view of a swing rotor according to an embodiment of the present invention. The figure which shows the relationship between the rotational speed of the rotor of the centrifuge in embodiment of this invention, and the opening area of an air path. The figure which shows the state which moved the valve of the centrifuge in the 4th Embodiment of this invention, and enlarged the opening area of the air path. The figure which shows the state which moved the valve of the centrifuge in the 4th Embodiment of this invention, and narrowed the opening area of the air path. The figure which shows the example of a change of the centrifuge in the 1st Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 101, 201, 301, 401 ... Centrifuge, 2 ... Frame, 2a ... Upper end opening, 2b ... Exhaust port, 3a ... Intake port, 3, 203, 303 ... -Door, 5 ... Motor, 5A ... Rotating shaft, 6 ... Rotor, 6A ... Rotor body, 6B ... Rotor cover, 8 ... Bowl, 8a ... Rotor chamber, 32 , 132, 232, 332, 432 ... valve mechanism, 32A ... first spring, 32B ... first plate, 41 ... rotor cover detection sensor, 42 ... rotor ID sensor, 43 ... Rotational speed sensor, 132A ... second spring, 132B ... second plate, 233, 333 ... door base, 234, 334 ... door plate, 235 ... A inner plate, 203a ... intake port, 203b, 303a ... door opening, 203c ... first gap, 203d ... second gap, 232A, 332A ... small motor, 232B, 332D ..Valve, 232C, 332E, output shaft, 303b, third gap, 332B, gear, 332C, rack gear, 432A, third spring, 432B, third plate

Claims (5)

A frame comprising an outer frame, having an upper end opening, and having an exhaust port;
A lid body that opens and closes the upper end opening and is formed with an air inlet;
A bowl disposed within the frame and fixedly supported by the frame and defining a rotor chamber together with the lid;
A rotating shaft extending into the ball and mounting a rotor to rotate the rotor in the rotor chamber;
A motor that is supported by the frame and that rotationally drives the rotating shaft;
Due to the pressure difference caused by the rotation of the rotor, an air passage was defined in which air was introduced from the intake port into the rotor chamber through the upper end opening, the rotor was cooled, and the air was discharged from the exhaust port. In the centrifuge
The centrifugal separator according to claim 1, wherein a valve mechanism for automatically changing an opening area of the air passage is provided in the air passage. The rotary shaft can be selectively mounted with various rotors,
The centrifuge according to claim 1, wherein the valve mechanism changes a flow path area in accordance with the types of the various rotors. The rotor includes a rotor main body including a sample mounting portion, and a rotor cover that covers the sample mounting portion and is detachable from the rotor main body.
The centrifuge according to claim 2, wherein the flow path area changes according to the presence or absence of the rotor cover.   The centrifuge according to claim 3, further comprising a cover detection sensor provided on the lid for detecting the presence or absence of the rotor cover. The rotation speed of the motor can be changed,
The centrifuge according to claim 2 or 3, wherein the flow path area changes according to the rotational speed of the rotor.

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