JP2003010734A - Centrifugal separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a centrifugal separator capable of efficiently checking any abnormality of the rotation signal, providing redundancy for the abnormality caused by a slip between a rotor and a drive shaft and the abnormality caused by the timing of the micro programming, and improving the load on users. SOLUTION: When the centrifugal separator has a mechanism for generating the signal to the rotor for the determination of the rotor, the input number of the rotation signal can be compared with the input number of the rotor determination rotation signal. In addition, in order to provide the redundancy for the abnormality of the signal caused by the slip between the rotor and the drive shaft and a trouble caused by the input timing of the signal to start the processing of the micro programming, the measurement timing is changed to avoid the same timing by clearing once the input signal number when any abnormality occurs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an abnormality processing of a rotation detecting portion of a device such as a centrifuge which freely attaches and detaches a sample and rotates at a high speed.

[0002]

2. Description of the Related Art A centrifuge of this type is operated by a user in accordance with a sample by determining so-called separation conditions such as rotation speed, operating time (separation time) and holding temperature. In recent years, due to advances in motor control methods, optimal control such as inverter control has advanced. In such a situation, the detection of the rotation speed is indispensable for obtaining a stable centrifugal force and for controlling the acceleration / deceleration in a short time.

On the other hand, if the rotation signal is abnormal such as unstable or lost, an inadvertent control may cause an overcurrent or overvoltage state, which may damage the control circuit. Also,
In some cases, the rotation speed may exceed the originally allowed rotation speed due to incorrect detection of the rotation speed or incorrect rotor identification. In a rotating device such as a centrifuge, strength is designed so as to support tens of thousands of operations at a rotational speed added to the permissible rotational speed in order to prevent damage to the rotating body.
However, in the case of the above-mentioned abnormality, it may be rotated more than expected, which is dangerous.

Conventionally, since the number of rotation signals for one rotation is constant, the number of rotation signals within a fixed time is calculated to calculate the number of rotations. When the rotation signal is abnormal (particularly when the signal is lost), it may be dangerous to rotate at a rotation speed higher than the rotation speed desired by the user. For this reason, when the rotation signal is not detected within a fixed time after the start of operation, or when a rapid change in the rotation speed occurs, it is configured to be abnormal.

On the other hand, the discrimination of the rotor is calculated from the difference in angle between the rotor discrimination rotation signals for one rotation. Furthermore, they were independently controlled.

[0006]

As described above, the function can be achieved by the conventional processing for the rotation signal and the rotor discrimination signal. However, if there is an abnormality in the number of rotation signals from the start of operation, there will be a difference between the actual number of rotations and the calculated number of rotations, and in the case of induction motors, etc., control will be carried out with an abnormal frequency, and a problem will occur. To do.

When a signal is used to identify the rotor,
In particular, when the number of signals per rotation is fixed and the rotor is discriminated by calculating the angle between the signals, it is possible to judge normality / abnormality by comparing the number of signals of both.

However, in the case of freely and frequently attaching and detaching the rotor like a centrifuge, a method of operating the rotor by mounting it on the drive shaft without fixing it with screws is becoming mainstream. In this case, the drive shaft directly connected to the motor starts decelerating when shifting from the settling state to the decelerating state, but the rotor may slip from the drive shaft due to its inertial force and may be decelerated with a delay. On this occasion,
A difference may occur in the number of signals between the two when normal, and it may be determined that the above processing is abnormal.

Further, the control system for executing these processes is subjected to microprogram processing, and another interrupt signal is input during the interrupt process (for example, when a rotation signal interrupt and a rotor discrimination signal interrupt are input during the timer interrupt process). ,
After the interrupt processing is finished, it is determined from which the processing is started. If the order is reversed with respect to the actual input, the number of signals will be wrong.

It is an object of the present invention to compare the signals of both and to make a judgment with redundancy even in the case of abnormality so that the user is not burdened.

[0011]

The above object is to provide a rotor for centrifuging a sample having a signal generator for discriminating the rotor, a drive shaft for rotating the rotor, a motor for applying a rotational force to the drive shaft, and a motor. The rotation signal generator associated with the rotation of the rotor, and a mechanism for processing the signal from the rotor discrimination signal generator and the signal from the rotation signal generator to discriminate the rotor and calculate the rotation speed. When,
This is achieved by having a function of comparing the number of signal inputs of the rotor signal generator.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A centrifugal separator according to the present invention is shown in FIGS.
This will be described with reference to FIG. FIG. 1 is a block diagram showing a centrifuge in the present embodiment, FIGS. 2A and 2B are flowcharts showing processing of the centrifuge in the present embodiment, and FIG.
Is a partially longitudinal side view showing the centrifuge in the present embodiment,
4 is a graph showing an example of a rotation signal, a rotor discrimination signal, and a timer interrupt signal, FIG. 5 is a flow chart showing control by each signal of FIG. 4, and FIG. 6 is another flow chart showing control by each signal of FIG. .

As shown in FIGS. 1 and 3, the user puts the sample into the test tube 14 and inserts it into the rotating body 13, and the driving device 1
5, the door 18 is closed and the start SW 19 provided on the operation / display unit 17 is turned on and rotated. The rotation signal generator 16 generates a signal according to the rotation. The control unit 1 controls the drive unit 16 so that the signal processing unit 4 is stably controlled at the rotation speed set by the operation / display unit 17.

On the other hand, the signal of the rotor discrimination signal device 2 of the rotor 13 is input to the signal processing section 4 via the rotor discrimination signal interface 3. A fixed number of signals are input as the signal of the rotor discrimination signal device 2 to the signal for one rotation of the rotation signal generator 16. 36 rotation signals are generated in one rotation.
In an example of the embodiment shown in FIG. 4, the signal processing unit is configured so that nine signals are input per revolution via a waveform shaping / dividing circuit. On the other hand, the rotor discrimination signal is 4 per revolution.
Occurs individually. Although the details of the rotor discriminating method are not described, the angle between the signals is calculated and the rotor is discriminated from the data stored in the storage element. As shown in the flow chart of FIG. 2, when the rotation signal number counter is 10 and the rotor discrimination signal number counter is 4, it is determined to be normal. Each counter value (assigned to the storage element) is incremented as interrupt processing every time the rotation signal and the rotor discrimination signal are input.

On the other hand, a timer interrupt (not a signal from the outside but configured to be generated inside the control device)
Then, when the rotation signal counter value becomes 10, it is checked whether the rotor discrimination rotation signal counter value is 4 or not. Four
If it is normal, each value is cleared and the process ends.

If it is not 4, in the case of claim 4, the memory value of the number of times of occurrence of abnormality is increased, and if it occurs 5 times in succession, an alarm is generated and the apparatus is stopped. In the case of claim 5, the rotation signal counter value is 3, which is basically the same,
Moreover, when an abnormality occurs, the rotation signal counter value and the rotor discrimination signal counter value are once cleared. This shifts the check timing of the rotation signal and the rotor discrimination signal. When slip occurs while the input interval of the rotation signal during deceleration increases, the increase in the input interval of the rotor discrimination signal is small and the rotor discrimination signal counter value becomes 5 for the rotation signal counter value 10. There is.
Redundancy is improved.

A time chart having the structure shown in FIGS. 4A and 4B can be easily considered. in this case,
A bold Gothic microprogram in the flowchart shown in FIG. 2 can be used. In the rotation signal interruption process, the rotation signal counter is incremented when the measurement start flag is on and the measurement end flag is off, and if the value is 10, the measurement end flag is turned on and the subsequent measurement is not performed. In the rotor discrimination rotation signal interrupt processing, the counter is not incremented when the measurement end flag is on. The rotor discrimination signal can be fixed. As a result, the normality / abnormality of the signal can be calculated in the timer interrupt processing. Redundancy with respect to abnormality caused by slip can be improved by the program of the basic part.

The abnormality due to timing has the following contents. The control system for executing the processing is microprogram-processed, and another interrupt signal may be input during the interrupt processing (for example, when the rotation signal interrupt and the rotor discrimination signal interrupt are input during the timer interrupt processing). According to the priority order of the interrupts, it is determined which one is to be processed after the processing is completed. If the order is reversed with respect to the actual input, the number of signals will be wrong.

In this apparatus, the order is timer interrupt, rotation signal interrupt, and rotor discrimination signal interrupt. When the rotation signal and the rotor discrimination signal are generated in an extremely short period of time, imbalance / vibration due to external factors or deviation of detection timing due to electrical external factors occur. Depending on the number of revolutions, the period of the timer interrupt and the period of the rotation signal have a fixed relationship, and the measurement is performed at the same timing, which increases the possibility of an abnormality. Since the measurement is once reset with an appropriate value of the counter value (3 in this example), redundancy can be provided even for abnormality due to timing.

[0020] Further, according to claim 6, if a check is made in the bold letters in the rotor discrimination signal processing, redundancy can be provided in response to imbalance / vibration due to external factors and deviation of detection timing due to electrical external factors. . In the example, the number of abnormal occurrences is 5 times, but this number does not restrict the present application. Further, in the example, the counter is once cleared with the counter value 3, but the present application is not restricted.

[0021]

According to the present invention, the abnormality of the rotation signal can be confirmed efficiently. Moreover, it is possible to provide redundancy with respect to the abnormality due to the slip between the rotor and the drive shaft and the abnormality due to the microprogramming timing as described above. This makes it possible to reduce the burden on the user.

[Brief description of drawings]

FIG. 1 is a block diagram showing a centrifuge in the present invention.

FIG. 2 is a flowchart showing the processing of the centrifuge in this embodiment.

FIG. 3 is a partially longitudinal side view showing the centrifuge in the present embodiment.

FIG. 4 is a graph showing an example of a rotation signal, a rotor discrimination signal, and a timer interrupt signal in this embodiment.

5 is a flowchart showing control by each signal of FIG.

FIG. 6 is another flowchart showing the control by each signal of FIG.

[Explanation of symbols]

1 is a control device, 2 is a rotor discrimination signal generator, 3 is an interface, 4 is a signal processor, 5 is a storage element, 11 is a centrifuge housing, 12 is a rotation chamber, 13 is a rotor, 14 is a test tube, Reference numeral 15 is a drive device, 16 is a rotation signal generator, 17 is an operation / display unit, 18 is a door, 19 is a start SW, 20
Is a stop SW, and 21 is a rotation speed display section.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hisabu Oyama             1060 Takeda Stock Association, Hitachinaka City, Ibaraki Prefecture             Hitachi Koki Information Technology             -In (72) Inventor Toshiyuki Suzuki             1060 Takeda Stock Association, Hitachinaka City, Ibaraki Prefecture             Hitachi Koki Information Technology             -In (72) Inventor Takayuki Watabiki             1060 Takeda Stock Association, Hitachinaka City, Ibaraki Prefecture             Hitachi Koki Information Technology             -In F-term (reference) 4D057 AC01 AC05 AD01 AE11 AF03                       BA21 BB02 CA07 CA09

Claims (7)

[Claims] 1. A rotor for centrifuging a sample having a signal generator for discriminating a rotor, a drive shaft for rotating the rotor, a motor for applying a rotational force to the drive shaft, and a rotation accompanying the rotation of the motor. A signal generator,
And a rotor signal generator having a mechanism for processing the signal from the rotor discrimination signal generator and the signal from the rotation signal generator to discriminate the rotor and calculate the rotation speed. A centrifuge having a function of comparing and processing the number of signal inputs. 2. The processing function has a storage element, and counts up the number of inputs for each interruption of the rotation signal and the signal from the rotor discrimination signal generator, and stores the number in the storage element for one rotation or number. The centrifuge according to claim 1, wherein the respective counter values are compared when the number of signals corresponding to the rotation is input. 3. The number of rotation signals input is compared with the number of signal inputs of the rotor discrimination signal generator, and when the value is not a constant value, it is determined to be abnormal and the apparatus is stopped. The centrifuge according to claim 2. 4. The number of rotation signals input is compared with the number of signal inputs of the rotor discrimination signal generator, and when the value is not a constant value, it is determined to be abnormal, the abnormality occurrence memory is counted up, and the rotation signal is further increased. 4. The centrifuge according to claim 1, wherein the number of inputs of each of the rotor discrimination signal and the rotor discrimination signal is once cleared. 5. The number of rotation signals input and the number of signal inputs of the rotor discrimination signal generator are compared, and if the values are not constant, it is determined that an abnormality has occurred, the abnormality occurrence memory is counted up, and the next processing is performed. 4. The counter values of the rotation signal and the rotor discrimination signal are once cleared when the number of rotation signals input is constant when there is a numerical value in the memory for the number of abnormal occurrences therein. The centrifuge according to any one of 1. 6. A control mechanism for performing microprogramming processing for each input of a rotation signal and a rotor discrimination signal, wherein the number of rotor discrimination signals in the processing of the rotor discrimination signal is one rotation or more than one signal corresponding to several rotations. The counter value of the rotor discrimination signal is decremented by 1 when the input number of the rotation signal is one less than the value corresponding to one rotation or several rotations and the rotation signal is input when the value is a value. Item 5. The centrifuge according to any one of Items 3. 7. The centrifuge according to any one of claims 4 to 6, wherein the apparatus is stopped when the number of memories for occurrence of abnormalities is a predetermined value or more.