JP2008104959A - Centrifugal machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifugal machine which is capable of efficiently discharging condensed water pooled in a rotor chamber with a simple structure. <P>SOLUTION: In the centrifugal machine 1 provided with a rotor 6 to hold and rotate a sample 8 to be separated, a driving device 15 to rotate and drive the rotor 6, a rotor chamber 5 to store the rotor 6, cooling equipment to cool the rotor 6, a door 11 to open and close the rotor chamber 5, drain piping 20 to connect the rotor chamber 5 with the outside and a control device 23 to control at least the driving of the driving device 15, a liquid level detector 21 and an openable/closable magnetic valve (valve) 22 are provided on the drain piping 20, and the magnetic valve 22 is opened when the liquid level is detected by the liquid level detector 21. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a centrifuge in which condensed water accumulated in a rotor chamber is discharged from a drain pipe to the outside of the rotor chamber.

  The centrifuge separates and purifies the sample by storing the sample to be separated in a tube or bottle and inserting it into the rotor and rotating the rotor at a high speed. The rotational speed of the rotor depends on the application. Differently, products ranging from low speed (maximum rotation speed of several thousand rpm) to high speed (maximum rotation speed of 150,000 rpm) are provided according to the application.

  There are various types of rotors depending on the application, such as an angle rotor with a fixed tube hole, a swing rotor in which a bucket loaded with a tube swings from a vertical state to a horizontal state as the rotor rotates, etc. There is. These various rotors can be attached to and detached from the drive unit.

  Some samples must be kept at a low temperature, but when the rotor rotates in the centrifuge, the temperature of the rotor is reduced by the air resistance generated between the outer surface of the rotor and the air in the rotor chamber. Because of its rise, many centrifuges are equipped with cooling devices.

  Here, a conventional centrifuge will be described with reference to FIG.

  FIG. 4 is a longitudinal sectional view of a conventional centrifuge. The illustrated centrifuge includes a swing rotor as a rotor. The left half of FIG. 4 shows the rotor stopped and the right half shows the rotor rotated. Show.

  In the illustrated centrifuge 1, the inside of the housing 2 is partitioned into upper and lower spaces by a horizontal partition plate 3, and a drum-shaped bowl 4 whose upper surface is opened is accommodated in the upper space. A rotor chamber 5 is formed inside the bowl 4, and a rotor 6 is accommodated in the rotor chamber 5. Here, a plurality of buckets 7 are swingably held at the tip of the rotor 6, and each of the buckets 7 is loaded with a plurality of tubes 9 containing a sample 8 therein. The bowl 4 is made of a material having high corrosion resistance such as stainless steel.

  The upper surface opening of the bowl 4 is opened and closed by a door 11 that pivots up and down about a hinge 10. When the door 11 is closed as shown in the figure, a door interposed between the door 11 and the bowl 4. The upper opening of the rotor chamber 5 is closed by the packing 12. The door packing 12 is made of an elastic material such as rubber.

  Further, a refrigeration pipe 13 is wound around the outer periphery of the bowl 4, and the periphery thereof is covered with a heat insulating layer 14 made of a highly heat insulating material such as a foam material. Although not shown, the refrigeration pipe 13 extends from the condenser of the refrigeration apparatus and is connected to the compressor.

  By the way, the center part of the bottom part of the bowl 4 is opened in a circle, and a rising part 4a is formed around the opening part. A driving device 15 such as a motor is mounted vertically on the partition plate 3 via a plurality of anti-vibration rubbers 16, and a shaft case 15 a extending above the driving device 15 is provided on the bowl 4. The rotor 6 penetrates through the opening at the bottom and faces the rotor chamber 5, and the rotor 6 is detachably mounted on the upper end of an output shaft (not shown) provided in the shaft case 15 a. Note that a portion where the driving device 15 penetrates the bowl 4 is fitted to the outer periphery of the driving device 15 and the rising portion 4 a of the bowl 4 and is blocked by the seal rubber 17.

  A drain hole 18 is opened at the bottom of the bowl 4, and a drain pipe 19 is welded around the drain hole 18 of the bowl 4. One end of a bendable tubular drain pipe 20 is connected to the drain pipe 19, and the drain pipe 20 extends through the side of the housing 2 to the outside of the housing 2. Yes.

  Thus, when the centrifuge 1 having the above configuration is operated, the door 11 is opened and a plurality of tubes 9 in which the sample 8 is accommodated are loaded in the bucket 7 supported by the rotor 6. The door 11 is closed to drive the driving device 15 and to drive a refrigeration device (not shown). Then, since an output shaft (not shown) of the driving device 15 rotates at a predetermined rotational speed, the rotor 6 attached to the upper end of the output shaft and the bucket 7 supported by the rotor 6 rotate in the rotor chamber 5 and stop. Sometimes the bucket 7 that is vertically supported as shown in the left half of FIG. 4 becomes horizontal as shown in the right half of FIG. 4 due to the centrifugal force caused by the rotation, and the tube 9 loaded therein and the sample 8 inside thereof. Becomes a horizontal state, and the sample in each tube 9 is centrifuged.

  At the same time, the liquid refrigerant flows through the refrigeration pipe 9 by driving the refrigeration apparatus, and the rotor chamber 5 is cooled through the bowl 4 by evaporating in the process. Therefore, heat generated by windage loss caused by the rotation of the rotor 6 is generated. It can be suppressed. In addition, since the circumference | surroundings of the bowl 4 are thermally interrupted by the heat insulation layer 14, the rotor chamber 5 is efficiently cooled.

  By the way, in order to keep the rotor 6 at a low temperature of, for example, 4 ° C., it is necessary to cool the bowl 4 to near 0 ° C. If the door 11 is opened immediately after the operation is stopped, the outside air is in the low temperature state in the rotor chamber 5. The moisture contained in the outside air is condensed on the surface of the bowl 4 cooled to around 0 ° C., and the condensed water accumulates at the bottom of the bowl 4. The condensed water collected at the bottom of the bowl 4 enters the drain pipe 19 through the drain hole 18 opened at the bottom of the bowl 4, and is discharged out of the housing 2 through the drain pipe 20.

  By the way, as described in Patent Documents 1 and 2 and the like, the condensed water accumulated at the bottom of the bowl 4 increases the rotational resistance of the rotor 6 and overloads the motor of the driving device 15 that drives the rotor 6. Cause excessive overheating, the dew condensation water enters the sample 8 in the tube 9 due to the flow of the wind generated in the rotor chamber 5 by the rotation of the rotor 6, makes the sample 2 unusable, or the dew condensation water in the bucket 7. It is known that even if an imbalance state is generated between the plurality of buckets 7 and the sample 8 is weight-balanced, problems such as inconvenience to the user such as operation stop due to imbalance occur.

Thus, various proposals for preventing the occurrence of the above-described problems have been made in Patent Documents 1 to 5.
Japanese Utility Model Publication No. 52-042445 No. 7-037721 JP-A-11-070346 Japanese Utility Model Publication No. 6-034746 Japanese Patent Application No. 2005-177841

  However, the configurations proposed in Patent Documents 1, 2, and 5 basically have no valve on the drain pipe. Here, in order to prevent the cooling efficiency of the rotor chamber from being reduced and the outside air containing moisture from flowing into the rotor chamber, the drain pipe must basically be normally closed. For this reason, Patent Document 1 proposes a configuration as shown in FIGS. 3 to 5, but according to the configuration shown in FIGS. 3 and 5, water is dried and disappears. In such a case, problems such as a decrease in cooling efficiency occur. Further, in the configuration shown in FIG. 4 of Patent Document 1, there is a possibility that problems such as clogging of sponges and the like may occur. In any configuration, it is possible to stably discharge condensed water to the outside without any problems. Not reached.

  On the other hand, Patent Documents 3 and 4 propose a configuration in which the valve is opened at a constant timing to discharge condensed water to the outside of the apparatus.

  However, as described in Patent Document 1 and Patent Document 5, condensed water accumulates in the drain pipe because the condensed water is moved by the flow of air generated when the rotor starts rotating. It is time to enter the drain hole. For this reason, in the configuration described in Patent Document 3 that synchronizes the opening and closing operation of the door and the opening and closing of the valve, the valve is closed when the rotor rotates, that is, when the door is closed in the centrifuge, so that dew condensation water is not generated. When there are many, the dew condensation water that cannot pass through the drain pipe overflows into the rotor chamber and causes various problems.

  Further, in the configuration proposed in Patent Document 4, the valve opens at a low speed immediately after the rotor starts rotating, but the valve opens unnecessarily even when there is no condensed water, which causes problems such as a decrease in cooling efficiency. May occur.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a centrifuge capable of efficiently discharging condensed water accumulated in the rotor chamber to the outside with a simple structure. is there.

  In order to achieve the above object, the invention described in claim 1 is a rotor that holds and rotates a sample to be separated, a driving device that rotationally drives the rotor, a rotor chamber that houses the rotor, and the rotor. In the centrifuge having a cooling device for cooling, a door for opening and closing the rotor chamber, a drain pipe connecting the rotor chamber and the outside, and a control device for controlling at least the driving of the driving device, A liquid level detector and a valve that can be opened and closed are provided.

  The invention according to claim 2 is the invention according to claim 1, wherein the control device opens the valve when the liquid level detector detects the liquid level.

  According to a third aspect of the present invention, in the second aspect of the present invention, the control device opens the valve when the rotational speed of the rotor is equal to or higher than a set value even when the liquid level detector detects the liquid level. It is characterized by not.

  According to a fourth aspect of the present invention, in the second aspect of the present invention, the control device opens the valve when the door is opened after the liquid level detector detects the liquid level and the rotation of the rotor stops. It is characterized by that.

  The invention according to claim 5 is the invention according to claim 2, wherein the control device opens the valve for a predetermined time when the liquid level detector detects the liquid level and the rotation of the rotor stops. And

  The invention according to claim 6 is the case where, in the invention according to claim 1, another liquid level detector is provided below the liquid level detector of the drain pipe, and both the liquid level detectors do not detect the liquid level. The valve is closed regardless of the rotation / stop of the rotor, and when both liquid level detectors detect the liquid level, the valve is opened regardless of the rotation / stop of the rotor to detect the lower liquid level. When only the vessel detects the liquid level, the valve is closed while the rotor is rotating, and the valve is opened when the rotation of the rotor is stopped and the door is opened.

  According to the first and second aspects of the present invention, every time a predetermined amount of condensed water accumulates in the drain pipe, the valve is opened to automatically discharge the condensed water to the outside of the machine. Water can be efficiently discharged outside the machine with a simple structure.

  According to the third aspect of the invention, since the control device does not open the valve when the rotor is rotating at a high speed equal to or higher than the set value, ambient temperature outside air containing moisture is drawn to the negative pressure in the rotor chamber. Thus, the drain pipe does not enter the rotor chamber, and the occurrence of problems such as an increase in the temperature of the rotor chamber due to the intrusion of outside air is prevented.

  According to the invention described in claim 4, since the valve is opened when the door is opened after the liquid level detector detects the liquid level and the rotation of the rotor stops, a problem due to the opening of the valve occurs. There is nothing.

  According to the fifth aspect of the present invention, when the liquid level detector detects the liquid level and the rotation of the rotor stops, the valve is opened only for a predetermined time. Occurrence of problems such as the temperature entering the chamber and the temperature of the rotor chamber rising is prevented.

  According to the sixth aspect of the present invention, when the condensed water is accumulated up to the level of the upper liquid level detector, the condensed water is discharged by opening the electromagnetic valve even when the rotor is rotating. Is accumulated at the level between both liquid level detectors, the solenoid valve is not opened while the rotor is rotating. It is possible to prevent the occurrence of problems such as an increase in the temperature of the rotor chamber due to outside air entering the rotor chamber.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

<Embodiment 1>
FIG. 1 is a longitudinal sectional view of a centrifuge according to Embodiment 1 of the present invention. In this figure, the same elements as those shown in FIG. Will not be described again. The centrifuge shown in FIG. 1 includes a swing rotor as a rotor, and the left half of FIG. 1 shows a stopped state of the rotor and the right half shows a rotated state of the rotor.

  In the present embodiment, a liquid level detector 21 is provided at the upper part of the drain pipe 20, and an electromagnetic valve 22 is provided at the lower part of the drain pipe 20, and the liquid transmitted to the control device 23 that controls the drive of the drive device 15. The control device 23 controls the opening / closing of the electromagnetic valve 22 based on a detection signal from the surface detector 21. Other configurations are the same as those of the conventional centrifuge 1 shown in FIG. It is.

  Thus, normally, the electromagnetic valve 22 is closed, and the condensed water accumulated at the bottom of the bowl 4 enters the drain pipe 19 through the drain hole 18 opened at the bottom of the bowl 4 and accumulates in the drain pipe 20. The water level gradually rises. Then, when the liquid level of the condensed water accumulated in the drain pipe 20 reaches the liquid level detector 21 and the liquid level detector 21 detects this, a detection signal is transmitted to the control device 23. Then, the control device 23 opens the electromagnetic valve 22 and discharges the condensed water accumulated in the drain pipe 20 to the outside of the machine.

  As described above, in the present embodiment, every time a predetermined amount of condensed water is accumulated in the drain pipe 20, the electromagnetic valve 22 is opened to automatically discharge the condensed water to the outside of the machine. Accumulated condensed water can be efficiently discharged outside the machine with a simple structure. Further, even when there is no condensed water, the electromagnetic valve 22 is not opened unnecessarily and the outside air is not introduced into the rotor chamber 5 from the drain pipe 20, so that the temperature in the rotor chamber 5 rises due to the outside air. Will not occur.

  By the way, the conditions for opening the electromagnetic valve 22 and the opening time can be set by rotating / stopping the rotor 6, rotating speed, or opening / closing the door 11.

  For example, even if the liquid level detector 21 detects the liquid level, the control device 23 can be prevented from opening the electromagnetic valve 22 when the rotor 6 is rotating at a high speed equal to or higher than a set value. When the rotor 6 is rotating at a high speed in the rotor chamber 5, a large negative pressure is generated in the rotor chamber 5. However, when the electromagnetic valve 22 is opened at this time, the ambient temperature outside air containing moisture is generated. Since the negative pressure in the rotor chamber 5 is drawn into the rotor chamber 5 from the drain pipe 20, problems such as an increase in the temperature of the rotor chamber 5 and the generation of extra condensed water occur. Therefore, in such a case, even if the liquid level detector 21 detects the liquid level, the electromagnetic valve 22 is kept open without being opened, thereby preventing the occurrence of the above-mentioned problem.

  Further, when the door 11 is opened after the liquid level detector 21 detects the liquid level and the rotation of the rotor 6 stops, the control device 23 may open the electromagnetic valve 22. When the rotation of the rotor 1 stops because the predetermined centrifugal separation process is completed, the user opens the door 11 and takes out the tube 9. At this time, the rotor chamber 5 is opened to the atmosphere, so the electromagnetic valve 22 is opened. However, no problem occurs, and when the condensed water is accumulated in the drain pipe 20 to reach the liquid level detector 21, the condensed water is discharged from the drain pipe 20 to the outside of the apparatus.

  Further, when the liquid level detector 21 detects the liquid level and the rotation of the rotor 6 stops, the control device 23 may open the electromagnetic valve 22 for a predetermined time. Even when the rotation of the rotor 1 is stopped because the predetermined centrifugal separation process is completed, the door 11 is not normally opened immediately, and the interior of the rotor chamber 5 is kept at a low temperature. When a predetermined amount of dew condensation water is accumulated in 20, the electromagnetic valve 22 is opened for a predetermined time, and after the dew condensation water is discharged out of the apparatus, the electromagnetic valve 22 is closed, thereby Generation | occurrence | production of malfunctions, such as the external air penetrate | invading into the rotor chamber 5 from the drain piping 20 and the temperature of the rotor chamber 5 rises, can be prevented.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIG.

  FIG. 2 is a longitudinal sectional view of the centrifuge according to the second embodiment. In this figure, the same elements as those shown in FIG. 1 are denoted by the same reference numerals. Is omitted.

  Also in the present embodiment, a liquid level detector 21 is provided at the upper part of the drain pipe 20 and an electromagnetic valve 22 is provided at the lower part of the drain pipe 20 to control from the liquid level detector 21 as in the first embodiment. The control device 23 controls the opening and closing of the electromagnetic valve 22 based on the detection signal transmitted to the device 23. The drain hole 18 is opened at the side of the rising portion 4a of the bowl 4. The difference from the first embodiment is that a drain pipe 19 bent in an inverted L shape is welded around the drain hole 18 of the rising portion 4a.

  Thus, in this embodiment, the same effect as in the first embodiment can be obtained. However, in this embodiment, since the drain hole 18 is opened at the side of the rising portion 4a of the bowl 4, the rotor 6, the condensed water flowing along the outer periphery of the rising portion 4a of the bowl 4 along with the air flow in the rotor chamber 5 is efficiently collected, enters the drain pipe 19 through the drain hole 18, and drain pipe 20 It is discharged out of the housing 2 through.

<Embodiment 3>
Next, Embodiment 3 of the present invention will be described with reference to FIG.

  FIG. 3 is a longitudinal sectional view of the centrifuge according to the third embodiment. In this figure, the same elements as those shown in FIG. 2 are denoted by the same reference numerals. Is omitted.

  In the present embodiment, another liquid level detector 24 is provided below the liquid level detector 21 in the drain pipe 20, and the control device 23 controls the opening and closing of the electromagnetic valve 22 by a detection signal from the liquid level detector 24. It was made to do. Hereinafter, the lower liquid level detector 24 is referred to as a “first liquid level detector”, and the upper liquid level detector 21 is referred to as a “second liquid level detector”.

  Thus, in this embodiment, the electromagnetic valve 22 is opened / closed by the presence / absence (ON / OFF) of detection of the first and second liquid level detectors 24, 21, the operation / stop of the rotor 6, and the opening / closing of the door 11. The breakdown is shown in Table 1.

以下、電磁バルブ２２の開閉制御を表１に従って説明する。

Hereinafter, opening / closing control of the electromagnetic valve 22 will be described according to Table 1.

  When both the first and second liquid level detectors 24 and 21 are OFF (no liquid level is detected), the condensed water does not accumulate up to the level of the first liquid level detector 24 below, so the rotor 6 Regardless of the rotation / stop of the motor and the opening / closing of the door 11, the electromagnetic valve 22 is closed, and the condensed water is not discharged from the drain pipe 20.

  Conversely, when both the first and second liquid level detectors 24 and 21 are ON (the liquid level is detected), the dew condensation water has accumulated up to the level of the second liquid level detector 21 above. Therefore, the electromagnetic valve 22 is opened regardless of the rotation / stop of the rotor 6 and the opening / closing of the door 11, and condensed water is discharged from the drain pipe 20.

  On the other hand, when the lower first liquid level detector 24 is ON and the upper second liquid level detector 21 is OFF, that is, the condensed liquid is the first liquid level detector 24 of the drain pipe 20. And the second liquid level detector 21, when the rotor 6 is rotating, the electromagnetic valve 22 is closed and the condensed water is not discharged, and the rotation of the rotor 6 is stopped. When the door 11 is opened, the electromagnetic valve 22 is opened to discharge the condensed water. Alternatively, immediately after the rotor 6 is stopped, the electromagnetic valve 22 is opened for a predetermined time or until the second liquid level detector 21 does not detect the liquid level, and condensed water is discharged outside the machine (outside the casing 2). By closing the electromagnetic valve 22, it is possible to prevent the occurrence of problems such as the outside air containing moisture entering the rotor chamber 5 from the drain pipe 20 and the temperature of the rotor chamber 5 rising.

  Therefore, according to the present embodiment, when the condensed water has accumulated up to the level of the second liquid level detector 21 above, the electromagnetic valve 22 is opened to collect the condensed water even while the rotor 6 is rotating. If the condensed water is accumulated at a level between the first liquid level detector 24 and the second liquid level detector 21, the electromagnetic valve 22 is not opened while the rotor 6 is rotating. Therefore, it is possible to prevent the occurrence of problems such as an increase in the temperature of the rotor chamber 5 due to the outside air at normal temperature entering the rotor chamber 5 due to the negative pressure generated in the rotor chamber 5 during the rotation of the rotor 6.

It is a longitudinal cross-sectional view of the centrifuge which concerns on Embodiment 1 of this invention. It is a longitudinal cross-sectional view of the centrifuge which concerns on Embodiment 2 of this invention. It is a longitudinal cross-sectional view of the centrifuge which concerns on Embodiment 3 of this invention. It is a longitudinal cross-sectional view of the conventional centrifuge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Centrifuge 2 Case 3 Partition plate 4 Bowl 4a Bowl rising part 5 Rotor chamber 6 Rotor 7 Bucket 8 Sample 9 Tube 10 Hinge 11 Door 12 Door packing 13 Refrigeration piping 14 Heat insulation layer 15 Drive device 15a Shaft of drive device Case 16 Anti-vibration rubber 17 Seal rubber 18 Drain hole 19 Drain pipe 20 Drain pipe 21 Liquid level detector 22 Electromagnetic valve (valve)
23 Control device 24 Liquid level detector

Claims (6)

A rotor that holds and rotates a sample to be separated; a driving device that rotationally drives the rotor; a rotor chamber that houses the rotor; a cooling device that cools the rotor; a door that opens and closes the rotor chamber; In a centrifuge provided with a drain pipe connecting the rotor chamber and the outside, and at least a control device for controlling the drive of the drive device,
A centrifuge according to claim 1, wherein a liquid level detector and a valve that can be opened and closed are provided in the drain pipe.   The centrifuge according to claim 1, wherein the control device opens the valve when the liquid level detector detects a liquid level.   3. The centrifugal separator according to claim 2, wherein the control device does not open the valve when the rotational speed of the rotor is equal to or higher than a set value even when the liquid level detector detects the liquid level.   The centrifuge according to claim 2, wherein the control device opens the valve when the door is opened after the liquid level detector detects the liquid level and the rotation of the rotor stops.   The centrifuge according to claim 2, wherein the control device opens the valve for a predetermined time when the liquid level detector detects the liquid level and the rotation of the rotor stops. Another liquid level detector is provided below the liquid level detector of the drain pipe, and when both liquid level detectors do not detect the liquid level, the valve is closed regardless of the rotation / stop of the rotor, When both liquid level detectors detect the liquid level, the valve is opened regardless of whether the rotor is rotating or stopped. When only the lower liquid level detector detects the liquid level, the rotor is rotating. 2. The centrifugal separator according to claim 1, wherein the valve is closed when the rotation of the rotor is stopped and the door is opened.

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