JP2007090325A - centrifuge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifuge easy to use, with no restriction in structure of a damper and lowerable in height. <P>SOLUTION: One end part 3A of a damper 3 is fixed to a base bottom part 2A, and the other end part 3B is fixed to a damper fixing part 4C of an inner casing 4, respectively. The inner casing 4 is supported on the damper 3, and comprises a roughly cylindrical circumferential wall 4A, and a bottom part 4B facing the base bottom part 2A. A motor 5 is directly fixed to the circumferential wall 4A by bolts, and has a perpendicularly extended output shaft 5A outputting a driving force of the motor 5. A power transmitting mechanism 7 transmits the driving force of the motor 5 to a shaft 6B. A rotor 8 for separating a separating object from a sample is coaxially connected to one end of the shaft 6B. An acceleration sensor 14 detecting acceleration of the inner casing 4 vibrated by the rotation of the rotor 8 is provided on the circumferential wall 4A. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a centrifuge, and more particularly to a desktop centrifuge installed on a laboratory table or the like.

  Centrifuges that use centrifugal force to separate samples include large-scale machines such as ultracentrifuges and desktop-type small centrifuges. The desktop centrifuge is installed on a laboratory table or the like and has a lid at the upper end for accessing the rotor chamber, so that the height needs to be lowered.

  The conventional centrifuge is arranged below the inner case so that the inner case is fixed to the outer case, and a part of the motor is located in the rotor chamber, and the damper is arranged between the motor and the base of the outer case. (For example, refer patent document 1). Another conventional centrifuge has a structure in which a plate-like base is disposed on a damper disposed on a base portion of an outer case, and an inner case and a motor are disposed side by side on the base (for example, , See Patent Document 2).

  Moreover, since the centrifuge rotates the rotating body containing the sample to be separated at a high speed, a large breaking energy is generated when the rotating body breaks. Safety requirements for centrifuges, as specified in IEC61010-2-02, an international standard, require a structure that can ensure safety even when the rotor breaks in half during high-speed rotation as the largest possible accident is doing. Specifically, there are restrictions on containment of rotor debris and movement of the device.

  In order to minimize the transmission of breaking energy to the housing, a cylindrical protector (protective wall) is provided on the outer periphery of the rotor chamber. When the rotor breaks and the fragments collide with the protector, the protector is deformed. There is a method of absorbing energy at the time of destruction by rotation. (For example, refer to Patent Document 3.)

JP-A-6-246192 U.S. Pat. No. 4,022,375 JP 2005-305400 A

  However, in the centrifuge described in Patent Document 1, although a part of the motor is located in the rotor chamber, the motor is disposed below the inner case. I couldn't do it, and it was not easy to use. Moreover, in the centrifuge described in Patent Document 2, since the motor is arranged side by side with the inner case, the height of the centrifuge can be reduced, but the height of the damper is the height of the centrifuge. The structure of the damper is limited. Further, the plate-like base is required to have sufficient rigidity, and the provision of the plate-like base leads to an increase in the number of parts and an increase in manufacturing cost. Further, even in the case of a centrifuge equipped with the protector described in Patent Document 3, a highly safe centrifuge is not realized while maintaining space saving.

  Therefore, an object of the present invention is to provide a centrifuge that can reduce the height without limiting the structure of the damper and is easy to use.

  In order to achieve the above object, the present invention provides an outer case, an inner case provided in the outer case and defining a rotor chamber by a peripheral wall portion and a bottom portion, and a motor provided in the outer case. A power transmission mechanism connected to the motor, a drive shaft connected to the power transmission mechanism, a rotor connected to the drive shaft and rotating together with the drive shaft, and one end fixed to the outer case, And a vibration isolating member that reduces vibration caused by rotation of the rotor.The motor is fixed to the peripheral wall portion of the inner case, and the other end of the vibration isolating member is connected to the inner case. A connected centrifuge is provided.

  Here, the drive shaft is rotatably supported by the inner case.

  Further, it is preferable that a counterweight is provided on the peripheral wall portion of the inner case so that the combined center of gravity of the motor and the inner case coincides with the axis of the drive shaft.

  A detecting means provided on the peripheral wall of the inner case for detecting the amount of vibration of the inner case due to rotation of the rotor; and when the amount of vibration detected by the detecting means exceeds a predetermined value, It is preferable to include a control unit that stops driving.

  The inner case includes a bowl for accommodating the rotor, and a protector for accommodating the bowl and acting as a protective wall, and the motor is fixed to the outer peripheral wall portion of the protector, and the vibration isolating member It is preferable that the other end of is connected to the protector.

  Here, it is preferable that the protector rotatably supports the drive shaft.

  Moreover, it is preferable that a counterweight is provided on the outer peripheral wall of the protector so that the combined center of gravity of the motor and the protector coincides with the axis of the drive shaft.

  Further, it is preferable that the bowl is suspended and supported by the outer case, and a cooling means is provided between the bowl and the protector and on the outer peripheral surface of the bowl. Here, it is preferable that a sufficient space is provided between the cooling means and the protector so that the protector does not contact the cooling means with respect to vibration of the protector.

  A detector provided on an outer peripheral wall of the protector for detecting the amount of vibration of the protector due to rotation of the rotor; and driving the motor when the amount of vibration detected by the detector is equal to or greater than a predetermined value. It is preferable to further include a control unit for stopping.

  Furthermore, it is preferable that the inner case is constituted by a protector that acts as a protective wall, the motor is fixed to the outer peripheral wall portion of the protector, and the other end of the vibration isolation member is connected to the protector.

  According to the centrifuge of claims 1 and 2, since the motor is fixed to the peripheral wall portion of the inner case and the other end of the vibration isolating member is connected to the inner case, the height of the centrifuge Can be lowered, and usability can be improved. Moreover, since the other end of the vibration isolator is connected to the inner case, the height of the centrifuge can be kept low even if the height of the vibration isolator is high, and the structure of the vibration isolator is limited. Therefore, the degree of freedom in selecting the vibration isolation member can be increased.

  According to the centrifugal separator according to claim 3 and claim 7, the counterweight is provided on the peripheral wall portion of the inner case so that the center of gravity of the inner case to which the motor is fixed coincides with the axis of the drive shaft. Therefore, when there is no counterweight, it is possible to prevent the motor and the inner case from making an elliptical motion due to the rotation of the rotor.

  According to the centrifuge of claim 4 and claim 10, the detection means provided on the peripheral wall portion of the inner case for detecting the vibration amount of the inner case due to the rotation of the rotor, and the vibration amount detected by the detection means are Since the control part which stops the drive of a motor when it is more than a predetermined value is provided, the safety | security of a centrifuge can be improved.

  According to the centrifuge of claims 5 and 6, the inner case is constituted by a bowl that accommodates the rotor and a protector that accommodates the bowl and acts as a protective wall, and the motor is fixed to the outer peripheral wall portion of the protector. And since the other end of the vibration isolator is connected to the protector, it is possible to provide a highly safe centrifuge while maintaining space saving.

  According to the centrifuge of claim 8, it is effective when the temperature of the sample must be kept at a low temperature, such as a biological sample. A good centrifuge can be provided. In particular, in combination with the centrifuge according to claim 1, even when the cooling means is attached, the height of the centrifuge can be kept low, and the structure of the vibration isolating member is not limited.

  According to the centrifuge of the ninth aspect, even when the protector vibrates, the protector can be prevented from hitting the cooling means.

  According to the centrifugal separator of the eleventh aspect, the bowl can be omitted and the rotor can be directly accommodated in the protector, and the structure of the device equipped with the protector is simplified.

  A centrifuge according to a first embodiment of the present invention will be described with reference to FIGS. The centrifuge 1 includes an outer case 2, three anti-vibration dampers 3, an inner case 4 that defines a rotor chamber, a motor 5, a shaft unit 6, a power transmission mechanism 7, and a rotor 8. Mainly prepared. The outer case 2 has a box shape with an upper end opened, and has a base portion 2A at the lower end. A lid 9 is provided at the upper end opening of the outer case 2 so as to be openable and closable.

  The three anti-vibration dampers 3 each have one end 3A and the other end 3B, and are arranged on the base 2A so as to form an equilateral triangle. One end portion 3A is fixed to the base portion 2A, and the other end portion 3B is fixed to three anti-vibration damper fixing portions 4C of the inner case 4 described later. The inner case 4 is supported by three anti-vibration dampers 3. The inner case 4 is a bowl that accommodates a rotor 8 to be described later, and includes a substantially cylindrical peripheral wall portion 4A and a bottom portion 4B facing the base portion 2A. Is defined. The three anti-vibration damper fixing portions 4C project from the peripheral wall portion 4A outward in the diameter direction. An opening 4d is formed in the bottom 4B.

  The motor 5 has an output shaft 5 </ b> A that is directly fixed to the peripheral wall portion 4 </ b> A by a bolt 20 and that extends in the vertical direction and outputs the driving force of the motor 5. The shaft unit 6 is fitted in the opening 4d of the bottom portion 4B and is disposed in the rotor chamber 10. The shaft unit 6 includes two bearings 6A, a shaft 6B that is a drive shaft that extends in the vertical direction and is rotatably supported by the bearing 6A, and a bearing holder 6C that supports the bearing 6A. The bearing holder 6C is an inner case. 4 is fixed. One end of the shaft 6 </ b> B is located in the rotor chamber 10, and the other end is located outside the rotor chamber 10. The power transmission mechanism 7 includes a belt 7 </ b> A, a first pulley 11, and a second pulley 12, and is disposed below the motor 5 and the shaft unit 6. The first pulley 11 is coaxially fixed to the lower end of the output shaft 5A, and the second pulley 12 is fixed to the other end of the shaft 6B. The belt 7A is attached to the first pulley 11 and the second pulley 12, and the driving force of the motor 5 is transmitted to the shaft 6B by the power transmission mechanism 7. The rotor 8, the shaft 6B, the belt 7A, the inner case 4, and the vibration damping damper 3 constitute a vibration system.

  The rotor 8 for separating the sample to be separated from the sample is coaxially connected to one end of the shaft 6B and can be rotated together with the shaft 6B. Further, two counterweights 13 are fixed to the peripheral wall portion 4A by bolts 21 between adjacent vibration-proof damper fixing portions 4C. The two counterweights 13 make the combined center of gravity of the motor 5 and the inner case 4 substantially coincide with the axis of the shaft 6B.

  An acceleration sensor 14 is provided as a means for detecting vibration of the rotor 8 above the vibration-proof damper fixing portion 4C shown in FIG. The acceleration sensor 14 detects the acceleration of the inner case 4 that vibrates as the rotor 8 rotates. The centrifuge 1 also has a control unit 15 that controls driving of the motor 5, and the control unit 15 is connected to the acceleration sensor 14 via the signal wiring 16 and connected to the motor 5 via the signal wiring 17. Has been. Further, the control unit 15 can periodically take in the acceleration detected by the acceleration sensor 14 via the signal wiring 16, and drive the motor 5 via the signal wiring 17 when the acceleration is equal to or greater than a predetermined value. Stop.

  Next, the operation of the centrifuge 1 will be described. By pressing a start switch (not shown), the control unit 15 starts driving the motor 5. The output shaft 5 </ b> A rotates by driving the motor 5, and this rotation is transmitted to the shaft 6 </ b> B via the belt 7. The rotor 8 also rotates with the rotation of the shaft 6B, and the sample to be separated is separated from the sample in the rotor 8. Further, although the inner case 4 vibrates by the rotation of the rotor 8, the vibration is reduced by the anti-vibration damper 3.

  As described above, since the motor 5 is directly fixed to the peripheral wall portion 4A, the height of the centrifuge 1 can be reduced and the usability can be improved. Further, since the vibration isolating damper 3 is fixed to the vibration isolating damper fixing portion 4C provided on the peripheral wall portion 4A, the height of the centrifugal separator 1 can be kept low even if the vibration isolating damper 3 is high. The structure of the vibration damper 3 is not limited, and the degree of freedom in selecting the vibration damper 3 can be increased. Further, since the counterweight 13 is fixed to the inner case 4, it is possible to prevent the motor 5 and the inner case 4 from elliptically moving due to the rotation of the rotor 8 when there is no counterweight 13. Moreover, since the control part 15 stops the drive of the motor 5 when the acceleration which the acceleration sensor 14 detects is more than predetermined value, the safety | security of the centrifuge 1 can be improved.

  In addition, since the centrifuge concerning 1st Embodiment does not have a protector, you have to contain destruction energy with the inner case 4 and / or the outer case 2 which are bowls. Therefore, the centrifuge of the first embodiment is limited to use with a rotor having a relatively low maximum rotational speed.

  Next, a centrifuge 101 according to a second embodiment of the present invention will be described with reference to FIGS. 3 and 4, the same members and elements as those constituting the centrifuge 1 in the first embodiment are denoted by the same reference numerals as those in FIGS. 1 and 2, and description thereof is omitted. To do.

  The inner case 60 according to the second embodiment includes a bowl 61 that accommodates the rotor 8, and a protector 62 that accommodates the bowl 61 and rotatably supports the shaft 6B and acts as a protective wall. The upper end of the bowl 61 is fixed to the upper cover 52B of the outer case 52 by screws (not shown) or by welding, and is supported by being suspended from the upper cover 52B. A through hole 61 a is formed at the center of the bottom of the bowl 61.

  A cooling pipe 63 for cooling the rotor 8 is wound around the outer peripheral surface of the bowl 61, and the periphery of the cooling pipe 63 is covered with a heat insulating material 64 made of a foam material. The coolant flows through the cooling pipe 63 to cool the rotor chamber 10 and cool the rotor 8 through the air in the rotor chamber 10.

  The protector 62 is for enclosing and absorbing energy at the time of destruction by deformation of the protector 62 when the rotor breaks and the fragments collide with the bowl 61 or the protector 62. Therefore, the protector 62 is manufactured from a highly rigid material such as steel. The protector 62 has a cylindrical shape surrounding the bowl 61, the cooling pipe 63, and the foam material 64. A through hole 62a for allowing the shaft 6B to pass therethrough is formed in the center of the bottom of the protector 62. The protector 62 fixes the bearing holder 6 </ b> C, and the bearing holder 6 </ b> C extends through the through hole 61 a of the bowl 61 into the rotor chamber 10. The relationship between the motor 5, the belt 7A, the three vibration damping dampers 3 and the protector 62 is the relationship between the motor 5, the belt 7A, the three vibration damping dampers 3 and the inner case 4 in the first embodiment. It is the same. That is, the protector 62 has a movable structure that is supported by the outer case 52 via the three vibration damping dampers 3. Further, a motor 5 for rotating the rotor 8 is fixed to the outer peripheral surface of the protector 62, and the drive is transmitted to the shaft 6B rotatably supported at the center of the bottom of the protector 62 by the belt 7A. The rotor 8, the shaft 6B, the belt 7A, the protector 62, and the vibration damping damper 3 constitute a vibration system.

  In order to avoid interference between the bearing holder 6C and the through hole 61a due to vibration of the protector 62, the inner diameter of the through hole 61a is set sufficiently larger than the outer diameter of the bearing holder 6C. Counterweights 13 and 13 are provided on the outer peripheral wall portion of the protector 62 so that the combined center of gravity of the motor 5 and the protector 62 substantially coincides with the axis of the shaft 6B. A cylindrical gap is provided between the outer peripheral surface of the heat insulating material 64 and the inner peripheral surface of the protector 62. The gap is sufficiently large to prevent the protector 62 from coming into contact with the heat insulating material 64 with respect to the vibration of the protector 62.

  In order to rotate the rotor 8 safely and stably, it is necessary to reduce the amplitude of the rotor 8 as much as possible. Further, since the protector 62 is made of a steel material, it is a heavy part among the parts constituting the centrifuge. By making this protector 62 into a vibration system like the rotor 8, the natural frequency of the entire vibration system is lowered, and more stable operation is possible. Furthermore, the natural frequency of the vibration system can be adjusted by changing the thickness of the protector 62 as required.

  As described above, in the centrifuge 101 according to the second embodiment, the space of the entire apparatus can be saved while the protector 62 is provided, and the cooling pipe 63 can be attached to the rotor 8 in the rotor chamber 10. The sample in the mounted sample container can be effectively cooled.

  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, although the acceleration sensor 14 is fixed to the outer peripheral portion of the inner case 4 and the outer peripheral portion of the protector 62, a position sensor that detects the position of the inner case 4 and the protector 62 that vibrates due to the rotation of the rotor 8 instead of the acceleration sensor 14. There may be. Moreover, although the motor 5 was being fixed to the surrounding wall part 4A with the volt | bolt 20, you may adhere | attach. Moreover, although the vibration-proof damper 3 was provided in three places, it is not restricted to this, Four or more places may be sufficient.

  Furthermore, in the second embodiment, the inner case includes a bowl 61 on which a cooling pipe 63 and a heat insulating material 64 are mounted, and a protector 62, but the bowl 61 may be omitted and only the protector 62 may be provided. With such a configuration, the number of parts is reduced and a more compact device can be realized.

The figure which shows the whole structure of the centrifuge by the 1st Embodiment of this invention. The top view of the centrifuge by the 1st Embodiment of this invention. The figure which shows the whole structure of the centrifuge by the 2nd Embodiment of this invention. The top view of the centrifuge by the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Centrifuge, 2, 52 Outer case, 2A Base part, 3 Anti-vibration damper, 4, 60 Inner case, 4A Circumferential wall part, 4B Bottom part, 4C Anti-vibration damper fixing part, 5 Motor, 6 Shaft unit, 6B Shaft, 7 Power transmission mechanism, 7A belt,
8 rotor, 11 first pulley, 12 second pulley, 13 counterweight,
14 acceleration sensor, 15 control unit, 61 bowl, 62 protector, 63 cooling pipe, 64 heat insulating material

Claims (11)

An outer case,
An inner case provided in the outer case and defining a rotor chamber by a peripheral wall portion and a bottom portion;
A motor provided in the outer case;
A power transmission mechanism connected to the motor;
A drive shaft connected to the power transmission mechanism;
A rotor connected to the drive shaft and rotating with the drive shaft;
In a centrifuge having one end fixed to the outer case and a vibration isolating member that reduces vibration caused by rotation of the rotor,
The motor is fixed to the peripheral wall portion of the inner case,
The other end of the vibration isolating member is connected to the inner case.   The centrifuge according to claim 1, wherein the drive shaft is rotatably supported by the inner case.   3. The counterweight according to claim 1, wherein a counterweight is provided on the peripheral wall portion of the inner case so that a combined center of gravity of the motor and the inner case coincides with an axis of the drive shaft. centrifuge. A detecting means provided on the peripheral wall portion of the inner case for detecting a vibration amount of the inner case due to rotation of the rotor;
The centrifuge according to any one of claims 1 to 3, further comprising a control unit that stops driving of the motor when a vibration amount detected by the detection unit is equal to or greater than a predetermined value. .   The inner case has a bowl for accommodating the rotor, and a protector for accommodating the bowl and acting as a protective wall. The motor is fixed to the outer peripheral wall of the protector, and the vibration isolating member The centrifuge according to claim 1 or 2, wherein an end is connected to the protector.   The centrifuge according to claim 5, wherein the protector rotatably supports the drive shaft.   The centrifugal separator according to claim 5 or 6, wherein a counterweight is provided on an outer peripheral wall portion of the protector so that a combined center of gravity of the motor and the protector coincides with an axis of the drive shaft. Machine.   The said bowl is suspended and supported by this outer case, The cooling means is installed in the outer peripheral surface of this bowl between this bowl and this protector, The any one of Claim 5 thru | or 7 characterized by the above-mentioned. The centrifuge according to one.   9. The centrifugal separator according to claim 8, wherein a sufficient space is provided between the cooling means and the protector so that the protector does not contact the cooling means with respect to vibration of the protector. Machine. Detection means provided on the outer peripheral wall of the protector for detecting the amount of vibration of the protector due to rotation of the rotor;
The centrifuge according to any one of claims 5 to 7, further comprising a control unit that stops driving of the motor when a vibration amount detected by the detection unit is equal to or greater than a predetermined value. .   The inner case is constituted by a protector that acts as a protective wall, the motor is fixed to an outer peripheral wall portion of the protector, and the other end of the vibration isolating member is connected to the protector. Item 3. The centrifuge according to item 1 or 2.

Images