JP2010125434A - Centrifuge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correct a starting voltage to a proper voltage for a reproducing signal electromagnetically induced from a magnetic recording medium to a magnetic head, and to enable actual operation data to be accurately reproduced and recorded, in a centrifuge having in a rotor the magnetic recording medium which holds actual operation data such as accumulated operation frequency or accumulated operation time of the rotor. <P>SOLUTION: A control device 8 finds the voltage of a reproducing signal Sa of the magnetic recording medium 9 detected by the magnetic head 10 to be smaller or larger than a proper range V1-V2. If the voltage is smaller than the lower limit value V1 of the proper voltage range, the control device 8 increases the revolution speed N of the magnetic recording medium 9 to N2 and, on the contrary, if the voltage is larger than the upper limit value V2 of the proper voltage range, reduces the revolution speed N of the magnetic recording medium 9 to N3 (N3<N2), thus varying the revolution speed of the magnetic head 10 for reproducing data. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a centrifuge capable of managing the operation results of a rotor, and more particularly to a centrifuge having a rotor with a magnetic recording medium capable of holding operation result data such as the accumulated operation number or accumulated operation time of the rotor.

  Since the centrifuge rotor (rotary body) that stores samples such as cells and genes needs high centrifugal acceleration, it needs to be rotated at a high speed of 100,000 revolutions per minute (100,000 rpm), for example. For this reason, since the centrifugal stress acting on the rotor increases, repeated use of the rotor may cause fatigue failure in the rotor material made of titanium alloy, geralumin, or the like. For this reason, the rotor is handled as having a finite life, and the number of accumulated operations or the accumulated operation time (for example, 5,000 times or 10,000 hours) is specified. When the rotor reaches a predetermined number of operations or operation time, the use is stopped at that point as a fatigue limit and discarded. Therefore, the rotor has a life, and it is necessary to manage the operation results of the rotor in order to operate the rotor safely. Generally, since the centrifuge body is configured so that various types of rotors can be detachably mounted, it is necessary to manage the operation results for each type of rotor.

  As an example of a conventional method of managing the operation of a rotor, as disclosed in Patent Document 1 below, a magnetic recording medium provided with a magnetic film is provided on the rotor, and data is recorded and reproduced by a magnetic head. A method for recording operation result data has been proposed.

  Such a conventional centrifuge includes a rotor that stores a sample to be centrifuged, a drive motor that rotates the rotor, a magnetic head that records or reproduces the operation result data of the rotor on the magnetic recording medium, A rotation sensor that measures the rotation speed of the rotor, and a control device (controller) that controls these drive motors, magnetic heads, etc., are provided, and a cylindrical magnet with a magnetic film deposited on the surface of the rotor. The recording medium is integrated. At the time of data recording, data indicating operation results such as rotor type, serial number, number of accumulated operations, accumulated operation time, etc., temporarily stored in the control device, are arranged close to the magnetic film. The magnet is magnetized to the SN pole at regular intervals on the cylindrical outer peripheral surface of the magnetic film, and the data arrangement is recorded. In addition, during data reproduction, data indicating the operation performance of the rotor is read by reading the recording information of the magnetic film arranged at regular intervals to the control device via a magnetic head arranged close to the magnetic film. Can be played.

  In this case, the magnetic head is provided with a magnetic core having a narrow gap, and a coil connected to the control device is wound around the core. When recording the actual data, a magnetic field is generated from the core gap by flowing a current from the control device to the coil while the rotor is rotated, and the magnetic film is magnetized by the magnetic pole defined according to the actual data. Also, during data reproduction, by rotating the rotor while maintaining the same rotational speed as during data recording, the magnetic head receives the magnetic flux generated from the magnetic film, and generates electromotive force by electromagnetic induction by the control device. It converts to an electrical signal. In addition, as shown in Patent Document 2 below, the performance data is recorded on the magnetic film by converting binary data into a binary signal of the MFM modulation method, and a plurality of types of pulses having different pulse widths. Some recording is performed by driving a magnetic head by a signal.

JP-A-3-181347 JP 2001-104834 A

  In the conventional centrifuge described above, the magnetic recording medium is provided in the rotor and rotates at a high speed together with the rotor, so that the magnetic recording medium needs to have a strength that can withstand high-speed rotation. For this reason, the magnetic recording medium is not as flexible as a cassette tape and cannot be brought into contact with the magnetic head at the time of data recording and reproduction. Therefore, there is a certain gap between the magnetic recording medium and the magnetic head. (Air gap) must be provided. For this reason, it turned out that the following problems arise.

  In particular, when the gap between the magnetic recording medium and the magnetic head is increased, the magnetic head is further away from the magnetic pole stored in the magnetic recording medium, so that the magnetic flux density traversed by the magnetic head is reduced and the magnetic head is The induced electromotive force is reduced. For this reason, at the time of reproducing data from the magnetic recording medium, it is necessary to provide an amplifier circuit for amplifying the electromotive voltage in the reading unit (reproducing circuit unit). Further, since the magnetic flux density received by the magnetic head decreases in proportion to the square of the distance from the magnetic pole of the magnetic recording medium, it is detected by the magnetic head based on the variation in the gap between the magnetic recording medium and the magnetic head. There was a problem that the electromotive voltage varied greatly.

  On the other hand, the magnetic film of the magnetic recording medium is formed by a deposition technique such as plating or vapor deposition. However, the magnetic film may have a dent due to slight scratches on the base material or the condition of the deposition technique (for example, the pH of the plating solution). Variations in thickness may occur. As a result, there is a problem in that the residual magnetic flux of the magnetic film varies and the electromotive voltage further varies during data reproduction.

  As a result, if there is a large variation in the magnetic flux density received by the magnetic head, the electromotive voltage of the magnetic head varies greatly. As a result, in the reproduction of a magnetic recording medium having a high magnetic flux density, the output of the amplifier circuit becomes an excessive output signal in which the signal waveform exceeding the drive power supply voltage of the amplifier is cut and the peak is cut off. However, when reproducing a magnetic recording medium having a small size, there is a problem that the interval between the magnetic poles of the recorded data cannot be reproduced. In either case, a correct binarized data signal cannot be reproduced.

  In order to solve the above problems, a manufacturing technique of the magnetic recording medium that reduces the variation in the thickness of the magnetic film can be considered. However, a slight scratch on the base material of the magnetic recording medium can be checked, and the pH and temperature of the plating solution. Therefore, it is necessary to precisely manage the conditions of the deposition technique such as the above, and there arises a problem that the cost of manufacturing equipment and manufacturing management becomes expensive.

  Accordingly, an object of the present invention is to provide a centrifuge having control means capable of solving the above-mentioned problems and accurately reproducing operation performance data on a magnetic recording medium mounted on a rotor via a magnetic head. There is to do.

  Another object of the present invention is to provide a relatively inexpensive centrifuge capable of storing operation record data such as the cumulative number of operation times or the cumulative operation time of a rotor.

  In order to solve the above problem, attention was paid to an electromotive voltage that changes in response to the rotation speed of a magnetic recording medium that records operation performance data. That is, the reproduction voltage of the operation record data recorded on the magnetic recording medium is induced by electromagnetic induction and amplified by the amplification circuit. Since this electromotive voltage is proportional to the rotational speed of the magnetic recording medium, we focused on changing the rotational speed of the magnetic recording medium during reproduction according to the magnitude of the magnetic flux density, that is, the electromotive voltage. .

  According to one aspect of the present invention, the control device changes the rotation speed of the magnetic recording medium for reproducing data in response to the magnitude of the reproduction signal voltage of the magnetic recording medium detected by the magnetic head. For example, when reproducing a magnetic recording medium having a high magnetic flux density and a large reproduction signal voltage, the rotational speed is reduced to suppress the generation of an electromotive voltage. Conversely, when reproducing a magnetic recording medium having a small magnetic flux density, the rotational speed is Is increased to increase the generation of the electromotive voltage, thereby stabilizing the electromotive voltage during data reproduction.

  According to another feature of the present invention, the control device includes an amplifier for amplifying the detection signal of the magnetic head, a differentiation circuit for differentiating the output signal of the amplifier, and an output signal of the differentiation circuit. A reproduction circuit unit including a binarized signal forming circuit for converting to a reproduced binary signal is provided.

According to the above feature of the present invention, since the generation of the electromotive voltage is adjusted in response to the rotational speed of the magnetic recording medium for recording the operation result data, even if the magnetic flux density received from the magnetic recording medium to the magnetic head varies greatly. , Can always reproduce accurate binarized signal. Thus, the operation data of the rotor can be automatically and accurately managed. The above and other objects, and the above and other features of the present invention will be further clarified from the following description of the present specification and the accompanying drawings. .

  Hereinafter, a centrifuge according to an embodiment of the present invention will be described with reference to the drawings. Note that components and elements having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof is omitted.

  1 is a block diagram showing the overall cross-sectional structure of a centrifuge according to an embodiment of the present invention, FIG. 2 is an enlarged structural view showing the relationship between the magnetic recording medium and the magnetic head shown in FIG. 1, and FIG. FIG. 4 is a functional block diagram of the centrifuge shown, and FIG. 4 is a block diagram of the regeneration circuit unit shown in FIG.

  First, the overall configuration of the centrifuge will be described. As shown in FIG. 1, the centrifuge 1 includes a housing (frame) 2 having a substantially square cross-sectional shape when viewed from above, and a sample container (not shown) such as a tube is provided inside the housing 2. A rotor (rotary body) 3 made of titanium alloy or aluminum alloy for holding, a drive motor 4 for applying a rotational driving force to the rotor 3, a rotor chamber defined by a bottom member (plate) 5a and a chamber 5b (Rotating chamber) 5 is provided, and a sliding door 6 that can be opened and closed by a knob 6a is attached to the upper opening of the rotor chamber 5 formed in the housing 2 so as to be opened and closed.

  The drive motor 4 is composed of, for example, an induction motor, and the rotor 3 can be driven by the control device 8 at low speed or high speed. The rotational speed of the rotor 3 that is rotationally driven by the motor 4 is detected by a rotation sensor 7 provided close to the bottom of the rotor 3. As shown in the functional block diagram of FIG. 3, the detection value (rotation signal) of the rotation sensor 7 is input to the control device (controller) 8, and the control unit 8e compares and calculates the detection value and the set value. The rotational speed of the motor 4 is controlled. The rotation signal of the rotation sensor 7 is also used as a synchronization signal with respect to an input signal (pulse signal) of operation performance data.

  As shown in FIG. 2, a cylindrical magnetic recording medium 9 is provided at the bottom of the rotor 3. A cylindrical magnetic recording medium 9 includes a magnetic film (magnetic memory thin film) 9b formed on a cylindrical aluminum substrate 9a by a coating technique such as plating and vapor deposition, and a coating film (protective film) formed thereon. 9c. A magnetic head 10 for writing or reading operation performance data to or from the magnetic recording medium 9 is fixed to a moving member 10a that can be moved forward and backward in the horizontal direction X, and is written (recorded) or read ( At the time of reproduction), an appropriate gap (air gap) for causing electromagnetic induction in the vicinity of the magnetic recording medium 9 is secured in accordance with a command from the control device 8 described later. The cylindrical magnetic recording medium 9 and the magnetic head 10 operate as a kind of hard disk memory, and the magnetic recording medium 9 is regularly spaced along the circumference of the cylindrical magnetic film 9b by electromagnetic induction between the two. The SN magnetic pole is magnetized in a predetermined direction, and operation result data can be recorded.

  In this case, as the distance d2 between the magnetic recording medium 9 and the magnetic head 10 increases, the magnetic flux density received by the magnetic head 10 from the magnetic pole of the magnetic film 9b decreases, and as a result, the electromotive voltage electromagnetically induced in the magnetic head 10 increases. Get smaller. Further, since the magnetic flux density decreases in proportion to the square of the distance d2 from the magnetic pole, the magnetic flux density varies greatly due to a slight adjustment deviation of the gap d2, and the electromotive voltage may vary greatly.

  Furthermore, since the thickness d1 (for example, 9 μm) of the magnetic film 9b is very thin compared to the distance d2 (for example, 0.3 mm) between the magnetic film 9b and the magnetic head 10, an aluminum substrate ( The thickness of the magnetic film 9b may vary depending on the dent caused by slight scratches on the base material 9a and the conditions of the deposition technique. Due to the variation in the thickness d1, the residual magnetic flux of the magnetic film 9b varies, and the electromotive voltage of the magnetic head 10 may further vary during data reproduction. According to the present invention, such a problem at the time of data reproduction is solved.

  As shown in FIG. 3, the magnetic recording medium 9 is coupled to the control device 8 via the magnetic head 10. The control device 8 includes a control unit (microcomputer) 8e including a calculation unit 8a, a memory unit 8b, a display unit 8c, and a timer unit 8d, and further includes a drive unit 8f including an inverter drive circuit of the drive motor 4, and a magnetic unit. The write circuit unit 8h for outputting the operation result data write signal (input signal) Si to the head 10 and the operation result data read signal (reproduced analog signal) Sa from the magnetic head 10 are supplied to the control unit 8e. A reproduction circuit unit 8g that outputs the signal as a value signal Sd.

  According to the present invention, the electromotive voltage (reproduced analog signal) Sa detected by the magnetic head 10 at the standard rotational speed (for example, 1,000 rpm) of the magnetic recording medium 9 is first measured by the control unit 8e, and the voltage The drive unit 8f is controlled according to the value, and the rotational speed of the drive motor 4 according to the reproduction analog signal Sa is set. As will be described later, when the reproduction analog signal Sa is within an appropriate range (V1 to V2) (where V1 <V2) during reproduction of the magnetic head 10, the drive motor 4 (magnetic recording medium 9) rotates. When the speed N is controlled to the standard rotational speed N1 (1,000 rpm) and the reproduction analog signal Sa is smaller than the lower limit value V1 of the appropriate range (V1 to V2), the standard of the drive motor 4 (magnetic recording medium 9) is set. The rotation speed N is controlled to a rotation speed N2 (for example, 1,200 rpm) higher than N1. Further, when the reproduction analog signal Sa is higher than the upper limit value V2 of the appropriate range (V1 to V2), the standard rotation speed N of the drive motor 4 (magnetic recording medium 9) is set to a rotation speed N3 lower than N1 (for example, 800 rpm). ) To control. Thus, the electromotive voltage (Sa) induced in the magnetic head 10 during the reproduction of the magnetic head 10 is corrected.

  As shown in FIG. 4, the reproducing circuit unit 8g generates an electromotive voltage Sa electromagnetically induced in the magnetic pole head 10 in accordance with a change in the magnetic pole stored in the magnetic recording medium 9 (for example, a change from the N pole to the S pole). An amplifier 8g1 for amplifying, a differentiating circuit 8g2 for differentiating the amplified output signal S1 of the amplifier 8g1, a comparator 8g3 for comparing the waveform of the output signal S2 of the differentiating circuit 8g2 with a reference level, and a comparator 8g3 And a binarized signal forming circuit 8g4 for forming the binarized signal Sd from the output signal.

  As shown in FIG. 5, the reproducing circuit unit 8g reproduces the peak value of the recording signal (electromotive voltage) Sa of the magnetic recording medium 9 as a binarized signal (pulse period) Sd, and sets the pulse period Tr to, for example, The recorded information is recorded by setting three types of Tr = 1.0Tw, Tr = 1.5Tw, and Tr = 2.0Tw as digital information of the MFM modulation method, and finally, the control unit 8e performs digital information (for example, When Tr = 1.0Tw, the digital information is “1” “1”. As a technique for reproducing a binary signal subjected to the MFM modulation method from such a pulse period Tr, the technique disclosed in the above-mentioned Patent Document 2 related to the present applicant can be adopted.

  In the present invention, as described above, the reproduction binarization signal Sd shown in FIG. 5 is not output due to variations in electromotive voltage due to variations in magnetic flux density across the magnetic head 10, or reproduction binarization is performed. This prevents the correct information from being reproduced due to a deviation amount in the pulse period Tr of the signal Sd.

  The display unit 8c monitors the operation panel for inputting data indicating operation conditions such as the rotation speed of the rotor 3 and the time for performing centrifugation to the control unit 8e, and the display of input information and information during operation. It has a function.

  The memory unit 8b includes a ROM memory storing a control program for executing processing according to a predetermined procedure of the drive motor 4, and operations such as the accumulated operation number and accumulated operation rotation time recorded in the magnetic recording medium 9. A RAM memory for temporarily storing the reproduced result data and further storing updated operation result data to be recorded on the magnetic recording medium 9 is provided.

  The timer unit 8d is detected from the rotation sensor 7 and the first timer that measures the period (Tr) of the binarized reproduction signal pulse (Sd) [see FIG. 5 (d)] output from the reproduction circuit unit 8g. A second timer for measuring the period of the rotation signal (Sr).

Next, the operation control of the control device 8 will be described with reference to the time chart showing the operation mode of FIG.
When the operation of the centrifuge 1 is started at time t0, the rotor 3 starts to rotate by the drive motor 4. At time t1, the control device 8 rotates the drive motor 4 at a certain low rotational speed N1 (1,000 rpm). ) Settling control.

  Between time t <b> 1 and time t <b> 2, the control device 8 determines the voltage value of the reproduction analog signal Sa (see FIG. 5A) of the operation result data recorded on the magnetic recording medium 9 via the magnetic head 10. It is checked whether or not the maximum value or the average value is within a predetermined normal voltage range V1 to V2 (where V2> V1).

  After checking the voltage value of the reproduction analog signal Sa, at time t2 to t3, the control device 8 sets the drive motor 4 to a predetermined rotation speed according to the voltage value of the reproduction analog signal Sa. In this embodiment, when the voltage value is in the normal voltage range V1 to V2, the rotation speed N is continuously set to N1 (1,000 rpm), and the voltage is lower than the lower limit value V1 of the normal voltage range V1 to V2. When the voltage is low, the rotational speed N is set to N2 (1,200 rpm) higher than the standard value N1, or the rotational speed is controlled to increase so that the voltage range is in the range of V1 to V2. Furthermore, when the voltage value is a high voltage value exceeding the upper limit value V2 of the normal voltage range V1 to V2, the rotational speed N is set to N3 (800 rpm) or the voltage range is within the range of V1 to V2. It controls so that rotation speed may be lowered.

  In this way, by varying the rotational speed N in accordance with the voltage value of the reproduction analog signal Sa, the operation result data recorded on the magnetic recording medium 9 is reproduced via the magnetic head 10 from time t2 to time t3. Let At this time, the magnetic head 10 is disposed in the vicinity of the magnetic recording medium 9, and the past operation result data magnetized to the SN pole at regular intervals on the cylindrical magnetic film 9 b is transmitted via the magnetic head 10. As will be described later, the data is read by the control device 8 and temporarily stored in the memory unit (RAM unit) 8b of the control device 8. Here, when the reproduced operation result data has reached the life limit value of the rotor 3, the control device 8 notifies the display unit 8c that it is a failure or a life, or generates a warning alarm, At the same time, the rotation of the drive motor 4 is stopped.

  On the other hand, the control device 8 has a regeneration check function, and when the operation result data is stored in the memory unit 8b, the regenerated operation result data is stored in the memory unit 8b and stored last time. When the regenerative operation result data is smaller than the data, the control device 8 determines that there is a failure, generates a failure alarm, and stops the rotation of the drive motor 4. In addition, when the reproduction operation result data is equal to the data stored in the memory unit 8b, or when it is a numerical value larger than the data stored in the memory unit 8b, it is determined as normal and the control device 8 reproduces the reproduced data. Is stored in the memory unit 8b as the latest operation result data. Here, even when the operation result data reproduced is larger than the data stored in the memory unit 8b, the control device 8 is added with the result that the rotor 3 is operated by another centrifuge. It is judged that it is normal.

  The control device 8 accelerates the drive motor 4 during a period from time t3 to time t4, and from time t4 to time t5, a high-speed rotation speed (for example, 100,000 rpm) preset by the user as the rotation speed of the drive motor 4 is set. Settling control. During this period, the sample held in the rotor 3 is centrifuged by high speed rotation. After centrifugation, the control device 8 decelerates the drive motor 4 from time t5 to time t6, and again settles to the rotational speed N1 that is the reproduction standard speed from time t6 to time t7.

  From time t6 to time t7, an input signal of operation performance data is applied from the control device 8 to the magnetic head 10 to generate a magnetic field, thereby regularly displaying digital information on the cylindrical magnetic film 9b (see FIG. 2). New operation performance data is recorded by magnetizing the SN pole at intervals. In this case, the operation result data is recorded on the magnetic recording medium 9 by adding the current operation result data to the past data at the time of reproduction once stored in the memory unit 8 b of the control device 8.

  After the recording, the voltage value of the reproduction signal Sa of the operation performance data recorded on the magnetic recording medium 9 from time t7 to time t8 is checked. After the check, at time t8 to time t9, the control device 8 determines the rotational speed N of the drive motor 4 according to the voltage value of the reproduction signal Sa detected at time t7 to time t8, as in the case of time t2 to time t3. Is set to any one of N1, N2, and N3, or is controlled to an arbitrary rotational speed so that the voltage range falls within the range of V1 to V2. After settling to a predetermined rotational speed, the operation result data is reproduced, and it is confirmed whether the memory unit 8b is recorded correctly.

  When the reproduced operation result data does not match the data stored in the memory unit 8b at the time of writing, the control device 8 determines that a failure has occurred, generates a life display or an alarm on the display panel 8c, and drives the drive motor 4 Stop rotating. If the reproduced operation result data matches the data stored in the memory unit 8b, the control device 8 determines that the operation is normal, and the reproduced data reaches the life of the rotor 3 registered in the memory unit 8b. Check if it has been reached. When the life is reached, the control device 8 generates a life display or alarm and stops the rotation of the drive motor 4. If the service life has not been reached, normal operation of the centrifuge 1 is terminated at time t10.

  As described above, in the centrifuge 1 of the present invention, the true binary signal (by adjusting the rotation speed N of the rotor 3 at a low speed according to the voltage value of the reproduction signal Sa detected by the magnetic head 10). The digital signal) Sd can be reproduced. That is, when it is determined that the magnetic flux density received by the magnetic head 10 from the magnetic pole of the magnetic recording medium 9 during reproduction is low and the generation of electromotive force is small, the rotational speed of the magnetic recording medium 9 during reproduction is increased to increase the electromotive force. If the generation is corrected to be high and, conversely, it is determined that the magnetic flux density is strong and the generation of electromotive force is large, the rotation speed of the magnetic recording medium 9 during reproduction is slowed down to correct the generation of electromotive force.

Next, the flowchart of FIG. 9 shows the voltage check of the reproduction signal Sa of the operation result data at the time t1 to the time t3 and the time t7 to the time t9 shown in FIG. 8, and the reproduction procedure of the operation result data based on the voltage check. Will be described with reference to FIG.
In step 100, the control device 8 sets the rotation of the drive motor 4 to a certain low rotational speed N1 (1,000 rpm).

  Next, at step 101, the control device 8 checks the voltage of the reproduction signal Sa of the operation result data recorded on the magnetic recording medium 9 via the magnetic head 10, and the voltage of the reproduction signal Sa is in the normal range V1 to V2. It is determined whether or not the value is smaller than the lower limit value V1 (see FIG. 5A).

  When it is determined in step 101 that the voltage of the reproduction signal Sa is smaller than the lower limit value V1 (in the case of Yes), the process proceeds to step 102, and the control device 8 performs a predetermined rotation of the drive motor 4 corresponding to the voltage smaller than the lower limit value V1. The speed is accelerated to a speed N2, and is set to a low rotational speed N2 (1,200 rpm in the embodiment).

  Next, in step 105, the operation result data is reproduced. At this time, the electromotive voltage of the reproduction signal Sa electromagnetically induced by the magnetic head 10 increases and increases as the rotational speed of the electric motor 4 (rotor 3) increases. Here, since the rotation speed during playback increases, the period of the magnetic pole during recording is different from the period of the playback signal, but the operation results are obtained by multiplying the period of the playback signal by the rotation speed ratio during recording and playback. Data can be accurately converted.

  When the voltage of the reproduction signal Sa is a value exceeding the lower limit value V1 of the normal range V1 to V2 in step 101 (No), the process proceeds to step 103, where the voltage of the reproduction signal Sa is checked. It is determined whether or not the value exceeds the upper limit value V2 of the normal range V1 to V2.

  When the voltage of the reproduction signal Sa exceeds the upper limit value V2 in Step 103 (Yes), the process proceeds to Step 104 where the control device 8 decelerates the drive motor 4 and rotates at a speed lower than the standard speed N1 (1,000 rpm). The speed is set to N3 (for example, 800 rpm).

  Next, in step 105, the operation result data is reproduced. At this time, the electromotive voltage electromagnetically induced by the magnetic head 10 decreases as the rotational speed decreases, and the voltage of the reproduction signal Sa also decreases. Here, since the rotation speed N at the time of reproduction is as small as N3, the period of the magnetic pole at the time of recording and the period of the reproduction signal are different, but by multiplying the period of the reproduction signal by the rotation speed ratio at the time of recording and reproduction. The driving performance data can be accurately converted.

  Further, when the voltage of the reproduction signal Sa is smaller than the upper limit value V2 in step 103 (No), the control device 8 determines that the voltage of the reproduction signal Sa is within the normal range (V1 to V2), and drives The operation result data is reproduced while the rotational speed N of the motor 4 is set to N1 (1,000 rpm).

  As is clear from the above embodiment, when the rotational speed N of the drive motor 4 is the standard speed N1 (1,000 rpm), the reproduction signal Sa detected from the magnetic head 10 is as shown in FIG. Even when it is smaller than the lower limit value V1 of the appropriate range (V1 to V2), after detecting the voltage value of the reproduction signal Sa, the rotational speed N of the drive motor 4 is corrected to N2 higher than N1, and rotated. The differentiation circuit output signal S2 as shown in (c) of FIG. 6 reproduced from the circuit 8g2 can be corrected to a large appropriate signal S2 as shown in (c) of FIG. As a result, it is possible to reproduce the proper reproduction binary signal Sd.

  Further, as shown in FIG. 7, even when the reproduction signal Sa detected from the magnetic head 10 exceeds the upper limit value V2 of the appropriate range (V1 to V2), the voltage value of the reproduction signal Sa is reversed. , The rotational speed N of the drive motor 4 is corrected to N3 and rotated at a reduced speed, and therefore, reproduced from the amplifier 8g1 and the differentiation circuit 8g2, as shown in (b) and (c) of FIG. Occurrence of peak cuts in the amplifier output signal S1 and the differentiation circuit output signal S2 is prevented. As a result, it is possible to correct the binary signal S2 as shown in FIG. 5C to obtain a correct zero cross point signal. That is, by appropriately correcting the voltage value of the reproduction signal Sa of the magnetic head 10, it is possible to prevent the generation of an illegal pulse cycle Tr.

  As will be apparent from the above description of the embodiment, the voltage of the reproduction signal is stabilized by changing the reproduction rotation speed of the magnetic recording medium (drive motor) according to the voltage of the reproduction signal of the operation result data. , Driving performance data can be accurately reproduced. In addition, according to the present invention, even a magnetic recording medium that could not be used outside the normal range of the reproduction signal voltage can be operated and the yield can be improved.

  As mentioned above, although the invention made | formed by this inventor was demonstrated based on embodiment, this invention is not limited to the said embodiment, A various change is possible within the range which does not deviate from the summary.

The whole block diagram of the centrifuge which concerns on embodiment of this invention. The block diagram which expanded the magnetic recording medium of the centrifuge shown in FIG. 1 partially. The functional block diagram of the centrifuge shown in FIG. The block diagram of the reproduction | regeneration circuit part in the functional block diagram of the centrifuge shown in FIG. FIG. 4 is an output signal waveform diagram of the reproduction circuit unit shown in FIG. 3. The output signal waveform diagram based on the minute reproduction input voltage of the reproduction circuit unit. The output signal waveform diagram based on the excessive reproduction input voltage of a reproduction circuit part. The time chart which shows the operation mode of the centrifuge shown in FIG. The control flowchart which shows the procedure of the check of the reproduction signal voltage of the driving performance data in the centrifuge shown in FIG. 1, and the driving performance data reproduction.

Explanation of symbols

1: Centrifuge 2: Housing (frame) 3: Rotor 4: Drive motor 5: Rotor chamber 5a: Bottom member (plate) 5b: Partition member 6: Door 6a: Door knob 7: Rotation sensor 8: Control device ( controller)
8a: arithmetic unit 8b: memory unit 8c: display unit 8d: timer unit 8e: control unit 8f: drive unit 8g: playback circuit unit 8h: writing circuit unit 8i: switching circuit unit 9: magnetic recording medium 9a: aluminum substrate 9b : Magnetic film 9c: Coating film (protective film) 10: Magnetic head 10a: Moving member

Claims (2)

A rotor having a magnetic recording medium that is rotationally driven by a motor in a state in which a sample is stored and records data, and the magnetic recording medium for reproducing data of the magnetic recording medium or recording data on the magnetic recording medium A magnetic head disposed at a position close to the magnetic head, a rotation sensor for detecting a rotation speed of the rotor, rotation of the motor based on a rotation detection signal of the rotation sensor, and the magnetic recording medium A centrifuge having a control device for controlling the magnetic head so as to reproduce data or record data,
The control device changes a rotation speed of the magnetic recording medium for reproducing data in response to a magnitude of a reproduction signal voltage of the magnetic recording medium detected by the magnetic head. .   The control device includes an amplifier for amplifying the detection signal of the magnetic head, a differentiation circuit for differentiating the output signal of the amplifier, and a signal for converting the output signal of the differentiation circuit into a reproduced binary signal. The centrifuge according to claim 1, further comprising a reproduction circuit unit including a binarized signal forming circuit.

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