Patent Publication Number: US-7909751-B2

Title: Method for sterilizing a centrifugal separator

Description:
The present application is a divisional of application Ser. No. 12/477,258, filed on Jun. 3, 2009, which is a continuation of application Ser. No. 11/175,375, filed Jul. 7, 2005, now U.S. Pat. No. 7,591,775 B2, the contents of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to a centrifugal separator for centrifugally separating a sample at inside of a rotor rotated at high speed in a rotor chamber. 
       FIG. 14  and  FIG. 15  show a background art of a centrifugal separator of this kind. 
     That is,  FIG. 14  is a front view of a centrifugal separator of a background art,  FIG. 15  is a side view showing operation of attaching and detaching a rotor in the centrifugal separator, and a centrifugal separator  1 ′ of the illustrated example is constituted by a rotating apparatus portion  10 , a sample injecting apparatus  100 ′ and a control apparatus portion  200  arranged on both sides thereof as shown by  FIG. 14 . 
     The rotating apparatus portion  10  is provided with a chamber  12  in a cylindrical shape on a base  11  fixed onto a floor face  2  by a plurality of pieces of bolts  3 , and a rotor  13  in a cylindrical shape shown in  FIG. 15  is rotatably set to be inserted into the chamber  12 . Further, an upper rotating shaft  14  and a lower rotating shaft  15  are respectively extended vertically upward and downward from the rotor  13 , and the upper rotating shaft  14  is connected to a drive portion  30  installed on an upper plate  16  in a shape of a circular plate. Further, the lower rotating shaft  15  is rotatably supported by a lower bearing portion  50  fixedly provided to the base  11 . Further, the drive portion  30  is provided with an electric motor, not illustrated, as a drive source, the upper rotating shaft  14  is inserted to be fixedly attached to an output shaft (motor shaft) of the electric motor, and a path (not illustrated) in a shape of a circular hole is penetrated through the upper rotating shaft  14  and the lower rotating shaft  15  for passing a sample. 
     Further, the rotating apparatus portion  10  is erected with a pair of left and right vertical lifts  70  which are hydraulically moved up and down on a back side (left side of  FIG. 15 ) of the chamber  12 , and a pair of left and right horizontal lifts  80  are horizontally attached between the vertical lifts  70 . Here, each of the horizontal lifts  80  is hydraulically moved forward and rearward in the horizontal direction, and a front end portion thereof is connected to the upper plate  16 . 
     Further, the sample injecting apparatus  100 ′ is provided with a frame member  101  movable on the floor face  2 , and the frame member  101  is installed with a sample tank  102  containing the sample, arranged with a liquid feeding pump  103  thereabove, and installed with a switch valve  104  and a flow meter  105  further thereabove. Further, a pipe  106  extended upward from the sample tank  102  is connected to a suction side of the liquid feeding pump  103 , and a pipe  107  extended from a delivery side of the liquid feeding pump  103  is connected to a sample injecting connector  17  connected to the lower bearing portion  50  of the rotating apparatus portion  10 . Further, a pipe  108  is extended to direct to the sample injecting apparatus  100 ′ from a sample discharging connector  18  connected to an upper end of the drive portion  30 , and an end portion thereof is inserted into the sample discharging tank, not illustrated. 
     Further, the control apparatus portion  200  is constituted by installing a control panel  202  at an upper portion of a case  201  in a shape of a rectangular box, and although not illustrated, inside of the case  201  is integrated with a drive portion power source, a refrigerator for cooling water and the rotor  13 , a vacuum pump for vacuuming a rotor chamber, not illustrated, at inside of the chamber  12 , an oil pump for supplying oil to respective portions of the rotating apparatus portion  10 , a hydraulic unit for driving the vertical lifts  70  and the horizontal lifts  80  and the like. Further, at the control panel  202 , rotational number, operating time, temperature and the like of the rotor  13  can be set and displayed, and a switch for starting and stopping the apparatus is provided thereto. 
     Further, according to the centrifugal separator  1 ′ having the above-described constitution, the sample in the sample tank  102  is injected into the rotor  13  from the sample injecting connector  17  of the rotating apparatus portion  10  by way of the pipes  106 ,  107  by the liquid feeding pump  103  of the sample injecting apparatus  100 ′. Further, the sample injected into the rotor  13  is centrifugally separated by rotating the rotor  13  at high speed, and the centrifugally separated sample (supernatant liquid or the like) is discharged from the sample discharging connector  18  to the sample discharging tank, not illustrated, by way of the pipe  108  as a discharge liquid, and the sample (separated sample) including particles sedimented in the rotor  13  is recovered by being discharged to a sample recovery tank, not illustrated, from a side of a lower portion of the rotor  13  by opening inside of the rotor  13  to the atmosphere after stopping to rotate the rotor  13 . 
     Meanwhile, after centrifugally separating the sample as described above, the rotor  13  is taken out from the chamber  12  and is cleaned, or sterilized as necessary and thereafter, the rotor  13  is integrated into the chamber  12 , since the rotor  13  is provided with a large weight, the rotor  13  is attached and detached by the vertical lift  70  and the horizontal lift  80  which are hydraulically operated as follows. 
     That is, when the vertical lift  70  is driven by hydraulic pressure supplied from the hydraulic unit, not illustrated, of the control apparatus portion  200 , the horizontal lift  80  and the upper plate  16  attached at a front end portion thereof are moved upward along with the drive portion  30  and the rotor  13  to be lifted to a position indicated by a chain line in  FIG. 15 . Further, when the horizontal lift  80  is driven hydraulically to move forward from the position, the upper plate  16  supported by the front end portion is moved forward to an escaping position indicated by a chain line in  FIG. 15  along with the drive portion  30  and the rotor  13  and therefore, the rotor  13  is taken out from the chamber  12  thereby. Further, the rotor  13  taken out from the chamber  12  is cleaned or further sterilized and thereafter, integrated into the chamber  12  by a procedure inverse to the above-described to be subjected to centrifugal separation again. Further, attachment and detachment of the rotor  13  by the hydraulic unit is described in Patent Reference 1, and a sterilizing processing by vapor is described in Patent Reference 2. 
     [Patent Reference 1] JP-A-2000-024551 
     [Patent Reference 2] JP-A-2000-042449 
     SUMMARY OF THE INVENTION 
     Meanwhile, when the sample to be separated centrifugally is, for example, influenza virus, Japanese encephalitis virus or the like, close attention is to be paid to handling thereof such that the sample is not contaminated by mixing other virus or bacteria, or an impurity or the like. 
     However, according to the centrifugal separating apparatus  1 ′ of the background art shown in  FIG. 14  and  FIG. 15 , there is needed an operation of taking out the rotor  13  from the chamber  12 , disassembling and sterilizing the rotor  13 , thereafter, integrating the sterilized rotor  13  again to integrate into the chamber  12  and thereafter, connecting the pipe  108  to the rotor  13  and therefore, in the operation, there is a possibility of mixing bacteria or the like floating in the atmosphere to a path of the sample (hereinafter, referred to as ‘sample line’), sterilizing cannot be carried out in a state of integrating the rotor  13  and therefore, it is difficult to centrifugally separate the sample in a state of maintaining a sterile state. 
     Further, also the sample injecting apparatus  100 ′ is disintegrated and thereafter integrated after sterilizing parts forming the sample line and the parts are connected to the rotating apparatus portion  10  and therefore, it is very difficult to completely maintain a sterile state. 
     The invention has been carried out in view of the above-described problem, and it is an object thereof to provide a centrifugal separator capable of realizing to centrifugally separate a sample under a complete sterile state by sterilizing a portion thereof with which at least the sample is brought into contact in a state of integrating a rotor. 
     In order to achieve the above-described object, the invention provides a centrifugal separator for centrifugally separating a sample by supplying the sample from a sample line into a rotor of a rotating apparatus portion and driving to rotate the rotor in a rotor chamber and discharging the centrifugally separated sample from the rotor via the sample line. The centrifugal separator includes a sterilizing apparatus for sterilizing at least a portion with which the sample is brought into contact by making a sterilizing fluid flow through the sample line. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention may be more readily described with reference to the accompanying drawings: 
         FIG. 1  is a front view of a centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 2  is a vertical sectional view breaking to show a portion of a rotating apparatus portion of the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 3  is a vertical sectional view of a drive portion of the rotating apparatus portion of the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 4  is a vertical sectional view of a lower bearing portion of the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 5  is a piping diagram of the vapor sterilizing apparatus of the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 6  is a piping diagram showing flow of vapor at a vapor sterilizing step in the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 7  is a piping diagram showing flow of air and cooling water at an air blowing and rotor cooling step in the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 8  is a piping diagram showing flow of a sample and cooling water in a centrifugally separating step in the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 9  is a piping diagram showing flow of air at air blowing step in the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 10  is a piping diagram showing flow of a separated sample and air at a separated sample recovering step in the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 11  is a piping diagram showing flow of distilled water in a cleaning step in the centrifugal separator according to Embodiment 1 of the invention. 
         FIG. 12  is a piping diagram showing flow of a sample and cooling water at a centrifugal separating step in a centrifugal separator according to Embodiment 2 of the invention. 
         FIG. 13  is a piping diagram showing flow of vapor at a vapor sterilizing step in the centrifugal separator according to Embodiment 2 of the invention. 
         FIG. 14  is a front view of a centrifugal separator of a background art. 
         FIG. 15  is a side view showing operation of attaching and detaching a rotor in the centrifugal separator of the background art. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the invention will be explained in reference to the attached drawings as follows. 
     Embodiment 1 
       FIG. 1  is a front view of a centrifugal separator according to Embodiment 1 of the invention. 
     Although first, a total constitution of a centrifugal separator  1  according to the invention will be explained in reference to  FIG. 1 , the centrifugal separator  1  according to the invention is constructed by a constitution similar to that of the centrifugal separator  1 ′ of the background art except that a vapor sterilizing apparatus  100  is constituted by integrating sterilizing means to the sample injecting apparatus  100 ′ of the centrifugal separator  1 ′ of the background art shown in  FIG. 14  and  FIG. 15  and therefore, in  FIG. 1 , elements the same as those shown in  FIG. 14  and  FIG. 15  are attached with the same notations and hereinafter, an explanation thereof at a second time will be omitted. 
     The vapor sterilizing apparatus  100  shown in  FIG. 1  is constituted independently from the rotating apparatus portion  10  and the control apparatus portion  200  for controlling the rotating apparatus portion  10 , inside thereof is constituted by integrating the liquid feeding pump  103  (refer to  FIG. 5 ) shown in  FIG. 14  and a control portion, not illustrated, other than various pipes (refer to  FIG. 5 ), mentioned later, and an upper portion thereof is respectively erected with a vapor connecting port  109 , a distilled water connecting port  110  and an air connecting port  111 . 
     Further, an operation panel  112  is provided at an upper portion of a front face of the vapor sterilizing apparatus  100 , an operator can set various kinds of operation by the operation panel  112 , and a control portion of the vapor sterilizing apparatus  100  controls an air drive valve and an electric valve in accordance with settings (conditions) inputted from the operation panel  112 . Further, numeral  102  designates the sample tank constituted by containing a sample to be centrifugally separated at inside thereof, the pipe  106  extended upward from the upper portion is connected to a suction side of the liquid feeding pump  103  (refer to  FIG. 5 ) integrated to inside of the vapor sterilizing apparatus  100 , and the pipe  107  conducted from the delivery side of the liquid feeding pump  103  is connected to the sample injecting connector  17  provided at a lower portion of the rotating apparatus portion  10 . Further, the pipe  108  conducted from the sample discharging connector  18  provided at the upper portion of the drive portion  30  of the rotating apparatus portion  10  is connected to a side portion of the vapor sterilizing apparatus  100  and is inserted into a sample discharge tank, not illustrated, provided in the vapor sterilizing apparatus  100 . 
     Next, details of the constitution of the rotating apparatus portion  10  will be explained in reference to  FIG. 2  through  FIG. 4 . Further,  FIG. 2  is a vertical sectional view breaking to show a portion of the rotating apparatus portion,  FIG. 3  is a vertical sectional view of a drive portion of the rotating apparatus portion, and  FIG. 4  is a vertical sectional view of the lower bearing portion of the rotating apparatus portion. 
     As shown by  FIG. 2 , a lower end flange portion of the chamber  12  of the rotating apparatus portion  10  is attached to the upper portion of the base  11  by a plurality of bolts  19 , and the rotor  13  in a shape of a circular cylinder is vertically contained rotatably at an axis center portion at inside thereof. Here, a core  20  in a cylindrical shape is concentrically contained at inside of the rotor  13 , and covers  21 ,  22  in a bowl-like shape are attachably and detachably screwed to upper and lower opening ends of the rotor  13 . Further, center portions of the upper and the lower covers  21 ,  22  are attachably and detachably attached with the upper rotating shaft  14  and the lower rotating shaft  15  in a hollow shape respectively by rotor nuts  23 ,  24 , the upper rotating shaft  14  and the lower rotating shaft  15  are respectively extended upward vertically and downward vertically, the upper rotating shaft  14  is connected to the drive portion  30 , mentioned later, and the lower rotating shaft  15  is rotatably supported by the lower bearing portion  50 . 
     Meanwhile, an upper end opening portion of the chamber  12  is attachably and detachably covered by the upper plate  16  in the shape of the circular plate, inside of the chamber  12  is formed with a rotor chamber S hermetically sealed by a case  25  containing the rotor  13 , and an outer peripheral side of the case  25  is concentrically arranged with a protector  26  in a cylindrical shape. Further, an outer peripheral face of the case  25  is wound with a cooling coil  27  as a vaporizing tube, and the rotor chamber S is deprived of latent heat to cool by an evaporating cold medium flowing in the cooling coil  27 . Further, a bottom portion of the rotor chamber S is opened with a drain hole  28  penetrated through an upper wall of the base  11 , and the drain hole  28  is connected with a connector  29 . Further, the rotor chamber S is connected to a vacuum pump, not illustrated, provided at the control apparatus portion  200  shown in  FIG. 1 . Further, the cooling coil  27  is supplied with the cold medium from a refrigerator, not illustrated, for cooling the rotor provided at the control apparatus portion  200 , and the cold medium is circulated in a cold medium pipe of a closed loop including the cooling coil  27  to repeat cooling operation. 
     Further, the drive portion  30  for driving to rotate the rotor  13  at high speed is installed above the upper plate  16  and a detailed constitution of the drive portion  30  will be explained in reference to  FIG. 3 . 
     The drive portion  30  includes an electric motor  31  as a drive source, an output shaft  32  in a hollow shape of the electric motor  31  is vertically arranged, and upper and lower portions thereof are rotatably supported by a pair of ball bearings  33 . Here, the electric motor  31  is constituted by fixedly providing a stator  35  at a surrounding of a rotor  34  rotated along with the output shaft  32 , and a cooling water jacket  36   a  is formed at a motor housing  36  for containing these. Therefore, the electric motor  31  is cooled by cooling water flowing in the cooling water jacket  36   a  to restrain heat generation thereof. Further, the cooling water is supplied from the refrigerator, not illustrated, provided at the control apparatus portion  200 . 
     Further, the output shaft  32  of the electric motor  31  is inserted to fixedly attach with the upper rotating shaft  14 , and a lower end portion thereof extended downward from the output shaft  32  of the upper rotating shaft  14  is rotatably supported by a pair of upper and lower sliding bearings  37 . Further, an upper end portion projected upward from the output shaft  32  of the upper rotating shaft  14  is screwed with a shaft head  38  in a cylindrical shape and an upper end portion of the shaft head  38  is brought into contact with a mechanical seal  39  constituted by low sliding plastic having heat resistance. Further, an outer peripheral face of the shaft head  38  is sealed by a pair of upper and lower lip seals  40 , and the lip seals  40  are lubricated by oil supplied from an oil injecting port  41 . 
     Further, the mechanical seal  39  is held movably in an up and down direction by a seal holder  43  held slidably in an up and down direction by a seal connector  42 , both members are urged downward by a spring  44  and therefore, the mechanical seal  39  is brought into contact with an upper end of the shaft head  38  by predetermined pressure. Further, the mechanical seal  39  is cooled by cooling water supplied from a cooling water inlet  45  and cooling water the temperature of which rises by being subjected to cooling is discharged from a cooling water outlet  46 . 
     Meanwhile, oil is supplied to the ball bearing  33  and the sliding bearing  37  other than the lip seal  40 , the oil is supplied from an oil pump, not illustrated, provided at the control apparatus portion  200  and is circulated in an oil pipe, not illustrated, constituting a closed loop to be subjected to lubrication of respective portions. Further, cooling water for cooling the electric motor  31  and the lip seal  40  is supplied from the refrigerator, not illustrated, provided at the control apparatus portion  200  to be subjected to cooling of respective portions. 
     Further, a center portion of an upper portion of the seal connector  42  is attached with the sample discharging connector  18  and the sample discharging connector  18  is connected with the pipe  108  shown in  FIG. 1 . 
     Further, an axis center of the drive portion  30  constituted as described above is formed with a sample line (a portion of a line d shown in  FIG. 5 ) by paths  42   a ,  43   a ,  39   a ,  38   a ,  14   a  in a shape of a circular hole penetrated through respective center portions of the seal connector  42 , the seal holder  43 , the mechanical seal  39 , the shaft head  38  and the upper rotating shaft  14 , a lower end of the sample line is communicated with an upper portion of inside of the rotor  13  and an upper end thereof is connected to the pipe  108  (refer to  FIG. 1 ) via the sample discharging connector  18 . 
     Next, details of the constitution of the lower bearing portion  50  will be explained in reference to  FIG. 4 . 
     The lower bearing portion  50  is for rotatably supporting the lower rotating shaft  15 , the lower rotating shaft  15  is rotatably supported by a sliding bearing  51 , and a lower end portion of a shaft head  52  screwed to a lower end portion thereof is brought into contact with a mechanical seal  53  constituted by low sliding plastic having heat resistance. Further, an outer peripheral face of the shaft head  52  is sealed by a pair of upper and lower lip seals  54 , and the lip seals  54  are lubricated by oil supplied from an oil injecting port  55 . Further, the sliding bearing  51  is cooled by cooling water supplied from a cooling water inlet  56  and is lubricated by oil supplied from an oil injecting port  57 . Further, cooling water is supplied from the refrigerator, not illustrated, provided at the control apparatus portion  200 . 
     Further, the mechanical seal  53  is held movably in an up and down direction by a seal holder  59  held slidably in an up and down direction by a seal connector  58 , both members are urged upward by a spring  60  and therefore, the mechanical seal  53  is brought into contact with a lower end of the shaft head  52  by predetermined pressure. Further, the mechanical seal  53  is cooled by cooling water supplied from a cooling water inlet  61  and cooling water the temperature of which rises by being subjected to cooling is discharged from a cooling water outlet  62 . 
     Meanwhile, oil supplied to the lip seal  54  and the sliding bearing  51  is supplied from the oil pump, not illustrated, provided at the control apparatus portion  200  and is circulated through an oil pipe constituting a closed loop to be subjected to lubrication of respective portions. Further, cooling water for cooling the lip seal  54  is supplied from the refrigerator, not illustrated, provided at the control apparatus portion  200  to be subjected to cooling of the lip seal  54 . 
     Further, the sample injecting connector  17  is attached to a center portion of a lower portion of the seal connector  58  and the sample injecting connector  17  is connected with the pipe  107  shown in  FIG. 1 . 
     Further, an axis center of the lower bearing portion  50  constituted as described above is formed with a sample line (a portion of the line d shown in  FIG. 5 ) in an up and down direction by paths  58   a ,  59   a ,  53   a ,  52   a ,  15   a  in a shape of a circular hole penetrated through respective center portions of the seal connector  58 , the seal holder  59 , the mechanical seal  53 , the shaft head  52  and the lower rotating shaft  15 , an upper end of the sample line is communicated with a lower portion of inside of the rotor  13 , and a lower end thereof is connected to the pipe  107  (refer to  FIG. 1 ) via the sample injecting connector  17 . 
     Next, a piping constitution of the vapor sterilizing apparatus  100  will be explained in reference to  FIG. 5 . 
       FIG. 5  is a piping diagram of the vapor sterilizing apparatus  100 , and pipings of the vapor sterilizing apparatus  100  are constituted by including existing sample line, cooling water line and air line. 
     That is, in  FIG. 5 , the sample line is constituted by including a line a reaching the liquid feeding pump  103  from the sample tank  102  (pipe  106  shown in  FIG. 1 ), a line b reaching a flow meter FM from the liquid feeding pump  103  via a valve VD  6 , a line c reaching the lower portion of the chamber  12  of the rotating apparatus portion  10  from the flow meter FM via valves VD 8  and VD 17 , the line d formed in the chamber  12 , a line e reaching a sample discharged tank (DRAIN 2 ), not illustrated, from the upper portion of the drive portion  30  via a valve VD 15 , a pressure gauge P 13 , valves VD 9  and VD 14 , and a line f reaching a sample recovery tank (FRACTION), not illustrated, by being branched from a downstream side of the valve VD 17  of the line c by way of a valve VD 18 . Further, the line c and the line e are respectively connected by lines g, h by interposing the valves VD 8  and VD 9 , the lines g, h are respectively provided with valves VD 7 , VD 10 . 
     Further, the cooling water line is a line for making cooling water of distilled water or the like (for example, ultra pure water (UFW)) from a distilling facility, not illustrated, and is constitute by including a line i reaching a connecting portion  47  at the upper portion of the chamber  12  from the distilling facility via a valve VD 2 , a pressure gauge P 12  and a valve VD 16 , a line j reaching the drive portion  30  from the connecting portion  47 , a line k reaching the lower bearing portion  50  from the drive portion  30 , and a line L reaching drain (DRAIN) from the lower bearing portion  50  via valves VD 19 , VB 5  (or VN 3 ), a thermometer TICA, a valve VB 4  (or steam trap ST 4 ), a sight glass SG and a check valve VS 4 . Further, according to the embodiment, distilled water at 4° C. is used as the cooling water. 
     Further, the air line is a line for making air for blowing or for driving a valve flow from a compressed air supplying facility of an air compressor or the like, not illustrated, and is constituted by including a line m reaching a filter F 1  from the compressed air supplying facility, not illustrated, via a pressure gauge P 11 , valves VBM 2 , VC 1 , VBM 3  and VB 1 , a line n connected to the line L from the filter F 1  via a valve VD 4 , a steam trap ST 3  and a check valve VS 3 , a line o reaching a filter F 2  via a valve VBM 1  by being branched from an upstream side of the valve VBM 2  of the line m, and a line p conducted from the filter F 2 . 
     Further, the vapor sterilizing apparatus  100  according to the embodiment adopts a piping constitution of adding a line for making steam (pure steam (PS)) as a sterilizing fluid flow to the sample line, the cooling water line and the air line, explained above. 
     That is, a line q extended from a steam generating apparatus, not illustrated, of a boiler or the like is connected between the valve VD 2  and the pressure gauge P 12  of the line i and a middle portion thereof is provided with valves VDC 1  and VD 1 . Further, a line r branched from a middle of the line q is connected to the line L via a valve VDM 1 , a steam trap ST 1  and a check valve VS 1 , a line s is branched from between the valve VB 1  and the filter F 1  of the line m, one end of the line s is opened to the atmosphere via a valve VB 2 , and other end thereof is connected to the line L via a valve VB 3 , a thermometer T 1 A, a steam trap ST 2  and a check valve VS 2 . Further, a line t branched from between the valve VD 2  and the pressure gauge P 12  of the line i is connected between the filter F 1  and the valve VD 4  of the line n via a valve VD 3 , a line u branched from between the valve VD 1  and the pressure gauge P 12  of the line q is connected between the liquid feeding pump  103  and the valve VD 6  of the line b via a valve VD 5 , and a line v branched from between the pressure gauge P 12  and the valve VD 16  is connected between the flow meter FM and the valve VD 8  via a valve VD 11 . Further, a line w branched from between the valve VD 6  and the flow meter FM of the line b is connected to the line L via valves VB 8  and VN 2 , and a line x branched from between the valves VD 8  and VD 17  of the line c is connected to the line L via a valve VD 12 , and a line y branched from between the valves VD 9  and VD 13  of the line e is connected to the line L via valves VD 14  and VB 6 . 
     Further, in the above-described, the valves VBM 1  through VBM 3  are manual ball valves, the valves VB 1  through VB 7  are air driven ball valves, the valve VDM 1  is a manual diaphragm valve, the valves VD 1  through VD 19  are air driven diaphragm valves, the valve VDC 1  is a diaphragm control valve, the valves VC 1 , VC 2  are pressure reducing valves and the valves VN 1  through VN 3  are needle valves. 
     Next, a series of operation of centrifugal separation by the centrifugal separator  1  according to the invention will be explained in an order of steps in reference to  FIG. 6  through  FIG. 11 , and the operation is executed by being processed by 1) vapor sterilizing step, 2) air blowing and rotor cooling step, 3) centrifugally separating step, 4) air blowing step, 5) separated sample recovering step and 6) cleaning step. Further,  FIG. 6  through  FIG. 11  are piping diagrams similar to  FIG. 5  showing flows of various fluids (steam, cooling water and air) and elements in the drawings, elements the same as those in  FIG. 5  are attached with the same notations. 
     1) Vapor Sterilizing Step: 
     The vapor sterilizing step is a step which is carried out after finishing centrifugally separating operation at a preceding time, taking out the rotor  13  from the chamber  12  to subject to disassembling, cleaning and sterilizing processings, integrating the rotor  13  subjected to the processings to integrate into the chamber  12 , connecting the pipe  107  to the sample injecting connector  17  of the lower bearing portion  50 , and connecting the pipe  108  to the sample discharging connector  18  of the drive portion  30 , and in the step, steam (PS) at high temperature is made to flow via paths indicated by arrow marks in  FIG. 6 . Here, steam temperature in the pipe is measured by the thermometer TICA, and the steam temperature in the pipe is controlled by controlling the valve VDC 1  such that the temperature falls in a range of 121° C. through 130° C., and controlling a flow rate of steam flowing in the pipe and a pressure in the pipe. Thereby, at least a portion with which the sample is brought into contact is sterilized by vapor. 
     That is, steam supplied from the steam generating facility of a boiler or the like flows in the line q and a portion thereof flows to the lines t, n, m, s to sterilize the lines. Further, water drops liquefied by being cooled in the midst are discharged from the steam traps ST 2 , ST 3 . 
     Further, other steam is made to flow to a side of the line i which is a cooling water line and a portion thereof is made to flow to a side of the line u constituting a side of the sample line. Further, a portion of steam flowing to the side of the line u is branched at the line e via the lines b, g and flows in the line d formed in the chamber  12  via the sample discharging connector  18  provided at the upper portion of the chamber  12  and reaches the line L via the lines c, x as shown by arrow marks in the drawing. Meanwhile, a portion of steam branched at the line e merges steam flowing in the line c via the line h and a remaining portion thereof is branched to a side of the valve VD 13  of the line e and the line y to reach the line L. Further, a portion of steam flowing in the line b passes through the line w to reach the line L. Further, the valve VN 2  is arranged at the line w to reduce a flow rate of steam flowing in the line w having a small resistance to make steam flow to sides of the lines c, e, d, k. In the line L, water drops of steam liquefied by being cooled at a middle thereof are discharged to the drain (DRAIN) via the steam trap ST 4  and the check valve VS 4 . 
     On the other hand, a portion of steam flowing from the line q to the side of the line i merges steam flowing in the line b via the line v and other steam flows in the lines j, k constituting the cooling water lines in illustrated arrow mark directions to reach the line L. Further, water drops liquefied by being cooled at a middle thereof are discharged to the steam trap ST 4 . Further, the valve VN 3  is arranged at the line L for reducing a flow rate of steam flowing in the lines e, k having small resistances and making steam flow to the sides of the lines c, d similar to the above-described. 
     Meanwhile, the above-described sterilizing processing is carried out in a state of maintaining inside of the rotor chamber S in the chamber  12  in a vacuum state by driving the vacuum pump, not illustrated, provided at the control apparatus portion  200 . When inside of the rotor chamber S is maintained in the vacuum state, the rotor chamber S forms a thermally insulating layer to reduce transfer of heat and therefore, the rotor  13  is heated by steam at an early stage, the rotor  13  is sterilized efficiently, and the chamber  12  is not brought under high temperature, which is safe. Further, the shaft heads  38 ,  52  and the lip seals  40 ,  54  are respectively brought into close contact with each other and therefore, there is also achieved an effect of firmly preventing invasion of steam. 
     Further, during the sterilizing processing, oil is supplied to the lip seals  40 ,  54 , ball bearing  33  and the sliding bearings  37 ,  51  of the drive portion  30  shown in  FIG. 3  of the rotating apparatus portion  10 . By making oil flow to the lip seals  40 ,  54 , the shaft heads  38 ,  52  and the lip seals  40 ,  54  are respectively brought into close contact with each other and invasion of steam is prevented by preventing deformation of lip portions of the lip seals  40 ,  54  by vapor pressure. As a result, leakage of steam from the parts and invasion of the atmosphere are firmly prevented by a seal effect by oil and sterilizing can firmly be carried out. Further, the ball bearing  33 , inside of the electric motor  31 , the sliding bearings  37 ,  51  and the like can be prevented from being rusted (corroded) by moisture of steam. 
     2) Air Blowing and Rotor Cooling Step: 
     When the vapor sterilizing step has been finished, the operation proceed to the successive air blow and rotor cooling step, in the step, as shown by arrow marks in  FIG. 7 , compressed air from a compressed air supplying facility of an air compressor or the like is made to flow to the filter F 1  via the line m and therefore, the filter F 1  is dried by air, and air subjected to drying of the filter F 1  is made to flow in the line n in an illustrated arrow mark direction and is discharged to the drain (DRAIN) by passing the check valve VS 3  from the steam trap ST 3 . 
     Further, cooling water from a distilling facility, not illustrated, is made to flow in the line i constituting the cooling water line in an illustrated arrow mark direction, and is made to flow to the line v which is the sample line from the line i. Further, cooling water which is made to flow to the line v cools the rotor  13  from inside thereof in a procedure of flowing upward in the line d at inside of the chamber  12  by passing the line c and thereafter flows to the line L by passing the line e and is discharged to the drain (DRAIN). Thereafter, the valve VD 2  is closed and the valve VD 3  is opened and air is blown for removing moisture in the steam pipe to dry. 
     In this way, when the rotor  13  which is brought under high temperature by being heated by steam in the vapor sterilizing step as the preceding step is cooled by cooling water, centrifugal separating operation of the sample at the successive centrifugally separating step can swiftly be carried out. 
     Further, when the centrifugally operating processing is not carried out immediately after finishing the vapor sterilizing step, the air blow and rotor cooling step, by compressed air supplied from the compressed air supplying facility of an air compressor or the like, the sample line and the cooling water line are maintained in a state of being pressurized to a predetermined pressure (0.1 MPa according to the embodiment) by compressed air, and invasion of the atmosphere into the lines to be processed can be prevented. As a result, invasion of bacteria floating in the atmosphere to the lines to be processed can firmly be prevented. 
     Meanwhile, bidirectional communication can be carried out between the control portion (not illustrated) provided in the vapor sterilizing apparatus  100 , and the control apparatus portion  200 . The control portion controls to operate the vapor sterilizing apparatus  100  based on a signal from the control apparatus portion  200 . For example, in order to confirm presence or absence of oil made to flow to the lip seal  40  to the drive portion  30  in the vapor sterilizing step, the control portion receives a signal from a sensor for detecting supply current (or supply voltage) to the motor for driving the oil pump or a signal from a flow rate meter arranged in the oil line, or receives a signal of a sensor for detecting a vacuumed state (reduced pressure state) in the chamber  12 , and controls to operate the vapor sterilizing apparatus based on the signals. 
     Further, the control portion of the vapor sterilizing apparatus  100  can transmit a signal indicating a state of opening and closing the valves of the vapor sterilizing apparatus  100 , or an operating state of temperatures in the pipes, flow rates of cooling water, compressed air, steam or the like to the control apparatus portion  200 , the control portion and the control apparatus portion  200  can always confirm the states of operating the vapor sterilizing apparatus  100  and the rotating apparatus portion  10  to each other, and the vapor sterilizing apparatus  100  and the rotating apparatus portion  10  are provided with output terminals for transmitting and receiving signals. 
     Further, also by integrating the control portion of the vapor sterilizing apparatus  100  in the control apparatus portion  200 , the states of operating the vapor sterilizing apparatus  100  and the rotating apparatus portion  10  can similarly be confirmed always by each other, and the centrifugal separator  1  can be made to constitute a safer and further highly reliable apparatus. 
     3) Centrifugally Separating Step: 
     When the portion with which at least the sample is brought into contact is sterilized by the vapor sterilizing step, and the filter F 1  is dried and the rotor  13  heated by vapor is cooled by the air blowing and rotor cooling step, the sample is centrifugally separated by the centrifugally separating step. 
     Prior to centrifugal separation, the line u is switched to a line on a side of the liquid feeding pump  103  frontward from the valve VD 6 , and similarly, the line y is switched to a line on a side of the sample discharging tank (DRAIN  2 ), not illustrated, rearward from the valve VD 14 . 
     In the centrifugally separating step, as shown by arrow marks in  FIG. 8 , solutions are sucked from the line a from a plurality of tanks, not illustrated, containing solutions having different densities successively from solutions having small densities by the liquid feeding pump  103  and thereafter, delivered to the line b after elevating pressures thereof. Further, the solutions delivered to the line b are supplied from the line c into the chamber  12  from the lower portion and supplied to inside of the rotor  13  shown in  FIG. 2  by passing the respective paths  58   a ,  59   a ,  53   a ,  52   a ,  15   a  formed in the seal connector  58 , the seal holder  59 , the mechanical seal  53 , the shaft head  52  and the lower rotating shaft  15  of the lower bearing portion  50  shown in  FIG. 4 . When the solution having a density gradient is filled at inside of the rotor  13 , the electric motor  31  of the drive portion  30  shown in  FIG. 3  is driven, the rotation is transmitted to the rotor  13  via the output shaft  32  and the upper rotating shaft  14  and therefore, the rotor  13  is driven to rotate at high speed (for example, 40,000 rpm) at inside of the rotor chamber S brought into a vacuum state. Thereafter, the centrifugally separating processing is carried out by supplying the sample in the sample tank  102  from the sample injecting connector  17  at the lower portion of the chamber  12  into the rotor  13  by the liquid feeding pump  103  and recovering a sediment liquid from the sample discharging connector  18  at the upper portion of the chamber  12 . Further, the sample may be supplied from the sample discharging connector  18  at the upper portion of the chamber  12  and the sediment liquid may be recovered from the connector  17  at the lower portion of the chamber  12 . Further, although according to the embodiment, the sample in the sample tank  102  is sucked by the liquid feeding pump  103 , there may be adopted a constitution of omitting the liquid feeding pump  103 , supplying compressed air into the sample tank  102  and pressurizing the sample by pressure of compressed air. 
     Further, when the rotor  13  is rotated, inside of the rotor chamber S is brought into a vacuumed state and therefore, a resistance of air of the rotor  13  is restrained to be low to enable to rotate the rotor  13  at high speed and heat generation in accordance with rotation of the rotor  13  at high speed is restrained to be low. Further, the rotor chamber S is cooled by vaporizing the cold medium flowing in the cooling coil  27  wound around the outer peripheral face of the case  25  and centrifugally separating processing is carried out while the sample is being cooled. 
     Further, at the same time, cooling water flows in the lines i, j constituting the cooling water line from a distilling facility, not illustrated, first, cools the mechanical seal  39  of the drive portion  30  shown in  FIG. 3 , thereafter, flows in the line k and supplied to the lower bearing portion  50 , and cools the mechanical seal  53  shown in  FIG. 4 . Further, cooling water the temperature of which rises by being subjected to cooling of respective portions is discharged to the drain (DRAIN) by passing the line L. 
     Further, when the rotor  13  is rotated at high speed in the rotor chamber S as described above, the sample filled at inside thereof is centrifugally separated, the centrifugally separated sample (sediment liquid or the like) is discharged to the sample discharge tank, not illustrated, from the sample discharging connector  18  via the pipe  108 , and separated particles sediment in the rotor  13 . 
     Meanwhile, in the vapor sterilizing step, in the state of integrating the rotor  13  to the chamber  12  and connecting the pipe  108  to the sample discharging connector  18 , steam is made to flow through the sample line and the cooling water line to thereby sterilize the lines by the vapor sterilizing apparatus  100  and therefore, the sample can centrifugally be separated under the sterilized state. Further, particularly, also the cooling water line is sterilized by making vapor flow to the cooling water line and therefore, bacteria included in cooling water are firmly prevented from being mixed to the sample and centrifugal separation of the sample is realized under a further complete sterile state. 
     4) Air Blowing Step: 
     When the sample has been centrifugally separated by the above-described centrifugally separating step, rotation of the rotor  13  and flow of cooling water are stopped, and as shown by arrow marks in  FIG. 9 , air from an air supplying facility the compressor or the like is made to flow to the cooling water lines i, j, k, L via the lines m, t to blow the lines m, t, j through L by air. 
     Further, the air blowing step is a step executed for removing cooling water and moisture remaining in the pipes prior to the successive separated sample recovering step. 
     5) Separated Sample Recovering Step: 
     When the air blowing step has been finished, the operation proceeds to the separated sample recovering step, and in the separated sample recovering step, the valve VB 2  is opened in a state of closing the valve VD 17  and opening the valves VD 3 , VD 11 , VD 7 , VD 15 , VD 18 . Then, the atmosphere flows in arrow mark directions of  FIG. 10  through the lines m, t, i, v, g, e, inside of the rotor  13  at inside of the chamber  12  is opened to the atmosphere and therefore, the sample (separated sample) including particles sedimented in the rotor  13  in the centrifugal separating step is discharged to be recovered by the sample recovery tank, not illustrated, by passing a portion of the line c and the line f from the sample injecting connector  17  at the lower portion of the chamber  12  by its own weight. 
     Meanwhile, according to the embodiment, in the air blowing step which is a preceding step of the separated sample recovering step, the lines m, t, i through L are blown by air and therefore, in recovering the separated sample, the atmosphere smoothly passes through the air line and the cooling water line (line m, t, i, v, g, e) to firmly open inside of the rotor  13 . As a result, the separated sample remaining at inside of the rotor  13  is discharged to outside of the rotor  13  to recover by its own weight. 
     6) Cleaning Step: 
     When the separated sample has been recovered by the separated sample recovering step, the operation proceed to the successive cleaning step and the sample line and the cooling water line are cleaned by distilled water. 
     Prior to cleaning, the line between the valve VD 6  and the liquid feeding pump  103  is switched to the line u between the valves VD 5  and VD 6 , similarly, a line on a side of the sample discharging tank (DRAIN 2 ), not illustrated, rearward from the valve VD 14  is switched to the line y. 
     In the cleaning step, as shown by arrow marks in  FIG. 11 , a portion of distilled water from a distilling facility, not illustrated, is made to flow from the line i to the side of the line u constituting the side of the sample line and other distilled water is made to flow to the side of the line i constituting the cooling water line as it is. Further, a portion of distilled water made to flow to the side of the line u reaches the line L via the lines b, w, reaches the line L via the lines b, c, x and the lines b, g, h, e, y, and flows downward through the line d formed in the chamber  12  from the line e, and flows in illustrated arrow mark directions in the lines c, x to reach the line L. Further, a remaining portion of distilled water flowing in the line i merges the line c via the line v, and reaches the line L by flowing from the line i through the lines j, k in illustrated arrow mark directions via the connecting portion  47 . Further, distilled water reaching the line L is discharged to the drain (DRAIN). 
     On the other hand, a portion of distilled water flowing to the side of the line i merges distilled water flowing through the line b via the line v, other distilled water flows in illustrated arrow mark directions through the lines j, k constituting the cooling water line and is discharged to the drain (DRAIN) via the line L. 
     Further, the respective lines are respectively cleaned by distilled water flowing in the above-described paths, the series of operation is finished here, and the sample line and the cooling water line can be cleaned by distilled water in the state of integrating the rotor  13  to the chamber  12  after recovering the centrifugally separated sample (separated sample). 
     Further, in the above-described series of steps, in the pipes through which vapor, cooling water, compressed air flow, the valves provided with the pipes are opened and all of other valves are closed. 
     Embodiment 2 
     Next, Embodiment 2 of the invention will be explained in reference to  FIG. 12  and  FIG. 13 . 
     The embodiment is characterized in adopting a constitution of circulating cooling water in a closed loop in the centrifugally separating step, and other constitution is similar to that of Embodiment 1, mentioned above. 
     That is, as shown by  FIG. 12 , a line z branched from the line i is connected to the line L, the cooling water line of a closed loop is constituted by the lines i, z, L and the lines j, k, a cooling water pump  90  is provided and a cooling water tank  91  arranged in a sterile chamber is connected to middles of the line z, and a cooling coil  92  is wound at a surrounding of the cooling water tank  91 . Further, the cold medium supplied from the refrigerator, not illustrated, is made to flow in the cooling coil  92  and cooling water flowing in the cooling water line of the closed loop is cooled by evaporating the cold medium. 
     In the vapor sterilizing processing in the case of adopting such a constitution, in a state of removing the cooling water tank  91  from the line z, as shown by arrow marks in  FIG. 13 , by making vapor flows through the lines i, z, j, k, L constituting the cooling water line constituting the closed loop, the lines i, z, j though L can be sterilized similar to other lines. Further, after the sterilizing processing has been finished, as shown by  FIG. 12 , the centrifugally separating step may be carried out by connecting the cooling water tank  91  to the line z in the sterilized chamber. 
     Further, according to the embodiment, cooling water which is expensive distilled water can be circulated to use in the closed loop without discharging cooling water to out of the system and therefore, an amount of using cooling water is reduced and cost of operating the apparatus can be restrained to be low. 
     Meanwhile, according to the above-described embodiment, the vapor sterilizing apparatus  100  is constituted independently from the rotating apparatus portion  10  and the control apparatus portion  200  and therefore, the vapor sterilizing apparatus  100 , the rotating apparatus portion  10  and the control apparatus portion  200  can be installed arbitrarily in accordance with a room of installing the centrifugal separator  1 , and the vapor sterilizing apparatus  100  can be used by being combined with the rotating apparatus portion  10  and the control apparatus portion  200  at a later stage as necessary. 
     Further, although according to the above-described embodiments, steam at high temperature is used as the sterilizing fluid, other arbitrary sterilizing fluid of a chemical (caustic soda (sodium hydroxide), ethanol, formalin) or the like can be used. 
     The invention is useful for the centrifugal separator which needs the sterilizing processing for preventing virus, bacteria, or impurity or the like from being mixed to the sample. 
     According to the invention, in the state of integrating the rotor to the rotating apparatus portion, at least the portion with which the sample is brought into contact is sterilized by making the sterilizing fluid of vapor or the like flow through the existing sample line by the sterilizing apparatus and therefore, centrifugal separation of the sample can be realized under a complete sterile state. 
     According to the invention, also the cooling water line is sterilized by making the sterilizing fluid flow also to the cooling water line for supplying cooling water to the rotating apparatus portion and therefore, bacteria included in cooling water can firmly be prevented from being mixed to the sample and centrifugal separation of the sample can be carried out under a further complete sterile state. 
     According to the invention, expensive distilled water or the like used as cooling water is circulated to be subjected to cooing and therefore, operating cost can be reduced by reducing an amount of using cooling water. 
     According to the invention, at least the portion with which the sample is brought into contact is firmly sterilized by vapor or the chemical solution and bacteria can firmly be prevented from being mixed to the sample. 
     According to the invention, the sterilizing processing is executed while supplying oil to the seal portion or the bearing portion in the rotating apparatus portion and therefore, leakage of the sterilizing fluid from the seal portion and the bearing portion and invasion of the atmosphere can firmly be prevented and a vacuum state in the rotor chamber is maintained. 
     According to the invention, inside of the rotor chamber is sterilized by maintaining the inside of the rotor chamber in the vacuum state and therefore, a thermally insulating layer is formed at inside of the rotor chamber, and in the case of using, for example, vapor at high temperature as the sterilizing fluid, the rotor is swiftly heated by vapor and the rotor is sterilized efficiently. 
     According to the invention, the line to be processed is pressurized by air after the sterilizing processing and therefore, invasion of the atmosphere into the line to be processed is prevented and bacteria floating in the air are firmly prevented from being mixed to the line to be processed. 
     According to the invention, as the post processing of the sterilizing processing step, the rotor the temperature of which is elevated by being heated by, for example, vapor is cooled by cooling water and therefore, centrifugal separation of the sample which is successively executed can swiftly be executed. 
     According to the invention, as the preprocessing of the separated sample recovering step of recovering the centrifugally separated sample, the air line and the cooling water line are blown by air and therefore, in recovering the separated sample, the atmosphere smoothly passes through the air line and the cooling water line, inside of the rotor is firmly opened to the atmosphere, and the separated sample remaining at inside thereof is discharged to outside of the rotor by its own weight to recover. 
     According to the invention, after recovering the centrifugally separated sample, in the state of integrating the rotor, the sample line and the cooling water line can be cleaned by distilled water, and it is not necessary to disintegrate or attach or detach the rotor, the pipes or the like in cleaning. 
     According to the invention, the sterilizing apparatus is constituted independently from the rotating apparatus portion and the control apparatus portion and therefore, the sterilizing apparatus and the rotating apparatus portion and the control apparatus portion can arbitrarily installed in accordance with a room of installing the centrifugal separator, and the sterilizing apparatus can be combined with the existing rotating apparatus portion and the existing control apparatus portion to use at a later stage as necessary. 
     According to the invention, the control portion for controlling the sterilizing apparatus can receive various signals from the control apparatus portion and can control the sterilizing apparatus properly based on the signals.