JP3633122B2 - Centrifuge - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a centrifuge having a rotor identification device for identifying individual types of a plurality of rotors mounted on a crown or the like of a centrifuge .
[0002]
[Prior art]
When there are multiple types of rotors mounted and used in the centrifuge, the temperature coefficient used for the temperature control calculation process for the maximum operation speed of the rotor, the operation pattern of the rotation speed, or the temperature management of the sample in the rotor Etc. are required on the centrifuge side, and various rotor identification devices corresponding to these have been invented and devised. As a conventional device of this type, as described in JP-A-6-198219, magnets are arranged on lattice points at equiangular intervals on the same circumference around the rotation axis of the rotor. A large number of sensors for detecting the presence / absence are arranged at intervals equal to or less than the equiangular interval, and the arrangement pattern of the magnets is coded. On the other hand, as described in Japanese Utility Model Laid-Open No. 6-41852, when coding the magnet arrangement pattern in the same method as described above, in order to specify the reading position of the arrangement pattern, it is arranged on the same circumference of the rotor. One of the magnets to be arranged is made different in the direction of the magnetic pole from the other magnets, and the sensors for detecting the presence or absence of these magnets are also made to detect different polarities, and a large number of magnet sensors are arranged twice.
[0003]
[Problems to be solved by the invention]
Therefore, such a conventional rotor identification device has the function of automatically identifying the rotor while the rotor is stopped as well as when the rotor is rotating, but the presence or absence of magnets arranged in a pattern coded on equidistant lattice points. The number of sensors for detecting the number of sensors is more than the number of equiangularly spaced lattice points, and since a large number of sensors are used, the failure rate as an identification device increases and the reliability decreases. When the rotor is rotated in the vacuum chamber, the sensor is generally also arranged in the vacuum brown chamber. However, in order to connect this sensor and the signal processing control unit placed in the atmosphere outside the vacuum chamber, a vacuum is used. Since an expensive multipolar hermetic seal function connector is required in the chamber, there is a problem that the reliability of connection is lowered and the economy is also deteriorated.
[0004]
In addition, the above failures and malfunctions may be caused by missing magnet placement patterns due to missing magnets attached to the rotor adapter or rotation imbalance due to rotor imbalance. There is a risk that the rotor may be rotated beyond the allowable number of revolutions, or the temperature control of the sample may be poor.
[0005]
The present invention has been made in view of the above-mentioned drawbacks of the prior art, and the object thereof is to enable rotor identification if the number of sensors for detecting the presence or absence of a magnet is at least one, and further, rotor identification error. It is an object of the present invention to provide a centrifuge having a rotor discriminating device that can eliminate as much as possible.
[0006]
[Means for Solving the Problems]
A motor, a rotor that is rotated by the rotational force of the motor, an identifier provided in the rotor, an identifier detection sensor that detects the presence or absence of the identifier, and an angle detection that detects a rotation angle of the identifier and the identifier detection sensor And a centrifuge having a controller for discriminating the arrangement pattern of the identifier from the signal output of the angle detector and the signal output of the identifier detection sensor, wherein the arrangement pattern of the identifier indicates a classification of the rotor And a portion for checking a portion indicating the classification of the rotor.
Furthermore, the arrangement pattern of the identifier includes a first code and a second code, and the second code is a third code derived by the control device according to a predetermined procedure. This is accomplished by being configured to match the code.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Specific embodiments of the present invention will be described below in detail with reference to the drawings.
[0008]
FIG. 1 is a partial cross-sectional side view illustrating an embodiment of a centrifuge incorporating a centrifuge rotor identification device according to the present invention. A crown 9 is fitted on the rotor shaft 3 of the rotor chamber 1 of the centrifuge, and the rotor 2 is placed on the crown 9. The rotor 2 is rotated by the rotational force of the motor 7. It is a provided door. An adapter 5 fitted with an identifier magnet 6 is attached to the bottom of the rotor 2, and a magnet sensor 4 such as a hall element or a magnetoresistive element serving as an identifier detection sensor is provided at a position facing the magnet 6 of the rotor chamber 1 and facing it. The signal output MG is input to the control device 11 that is outside the rotor chamber 1 and identifies the rotor 2 via the signal line 44 through the hermetic seal 10 serving as a connector. In order to detect the rotation angle of the rotation axis of the rotor 2 of the magnet 6 and the magnet sensor 4, a rotary encoder 8 serving as an angle detector is attached to the rotation axis of the motor 7, and the rotary encoder 8 is the rotation axis of the motor 7. The two-phase signal outputs φA and φB of the rotary encoder 8 are input to the control device 11 via the signal line 45.
[0009]
FIG. 2 is a diagram showing an arrangement pattern of the magnets 6 mounted on the adapter 5 attached to the bottom of the rotor 2 for identification of the rotor 2, and is on the same circumference around the rotation axis of the rotor 2. For example, the magnets 6 are arranged on a lattice of equiangular intervals divided into twelve, and in the illustrated example, d, e, g, h, i, j shown by solid circles on lattice points from a to l. , L with the magnetic poles in the same direction and seven magnets are mounted, and no magnets are mounted at the positions a, b, c, f, and k indicated by broken circles.
[0010]
3 is a diagram showing the arrangement pattern of the magnets 6 shown in FIG. 1 is No. 1 when the reading position is a in FIG. 2 is when the reading position is b. 12 respectively. In the arrangement pattern of the magnets 6 shown in FIG. 2, the case where the magnets 6 are present on the lattice points is set to “0” when the magnets 6 are not present, and “1” of “0001 1011 1101” when read from a clockwise. , “0” is a 12-bit identification code. At this time, one nibble is formed in units of 4 bits from the beginning, and expressed in hexadecimal, it becomes “1BD”, “1B” consisting of the first nibble and the second nibble is classified as a classification code, and “D” of the third nibble is classified This is a code check code. In this embodiment, the check code for the classification code is generated by subtracting two numbers “1” and “B” constituting the classification code from “F” from “F”. According to the calculation method, E−B becomes 3, and the complement of “3” or “0011” is taken to be “D” or “1101”.
[0011]
In FIG. 3, check code 1 indicates a hexadecimal check code according to the third nibble, and check code 2 indicates a check code obtained by the above calculation method. Here, since the reading position of the identification code cannot be specified to start from a as described above, reading may be performed from the position of b in another example. The identification code is a 12-bit identification code that is rotated to the left by 1 bit for the position a shown in FIG. 2 and the classification code “37” is read as “A”. The check code calculated from the classification code “37” by the calculation method is “B”, and the check code 1 and the check code 2 do not match, and it can be seen that reading from the position b is illegal. Similarly, no. 3 or less When the check positions 1 and 2 are sequentially changed up to 12 and the check codes 1 and 2 are compared, it can be determined that the reading is from an illegal position because they do not match in any case. Therefore, from the arrangement pattern of the magnet 6 shown in FIG. The classification code of 2 can be identified as “1B”.
[0012]
Similarly, FIG. 4 shows an example in which the classification code “1B” is changed to “27”, and the arrangement pattern is composed of six magnets. 1 to No. As shown in FIG. 6, the check code 1 and the check code 2 match, and the classification code cannot be uniquely specified. However, the identification codes “27A”, “4F4”, “9E8”, “3D1”, “7A2”, and “ If the six types of F44 ″ are handled as the same identification code, they can be distinguished from other identification codes. In the case of the present embodiment, in the case of the present embodiment, 149 types of identification codes can be obtained for the 12-bit identification code composed of the 8-bit classification code and the 4-bit check code. It is clear that a sufficient number of codes can be secured, but by increasing the number of constituent codes of the identification code and the check code, a larger number of identification codes can be obtained and identification errors can be eliminated more accurately. Needless to say, the method for generating the check code for the classification code is not limited to the present embodiment because of the use of parity.
[0013]
FIG. 5 is a block circuit diagram showing a specific example of the control device 11 for recognizing the rotor identification code having the above-described configuration. The signal output MG of the magnet sensor 4 is composed of a resistor and a capacitor. After passing through the noise absorption integrating circuit 13, a Schmitt such as 74HC14 is input to the P0 port of the microcomputer (hereinafter abbreviated as “microcomputer”) 28 via the inverter 16, and the magnet sensor 4 senses the presence of the magnet 6. At that time, ethics “1” is input to the PO port. Similarly, the two-phase signal outputs φA and φB of the rotary encoder 8 pass through the integration circuits 14 and 15 respectively, and then the first stage of the flip-flop 19 such as 74HC175 is input to the D input terminal via the Schmitt trigger inverters 17 and 18. The clock signal is supplied from the oscillator 20 to the clock terminal of the flip-flop 19. The D terminal input of the second stage of the flip-flop 19 is connected to the Q output of the first stage. As shown in the figure, the output of the first stage and the output of the second stage are exclusive such as 74HC86. The gates of OR gates (hereinafter referred to as exclusive OR) gates 21 and 23 are connected, and the exclusive OR gate 22 is connected to the first flip-flop for the two-phase signals φA and φB. The input terminals are connected, the outputs of these gates 21 and 23 are respectively connected to the input terminals 1A and 2B, 2A and 1B of a data selector such as 74HC158, and the output terminal of the gate 22 is connected to the select input terminal S of the data selector 24. Have been entered. The inverted output terminals 1Y and 2Y of the data selector 24 are input to the exclusive OR 27, and the output of this gate is connected to the interrupt input terminal iRQ of the microcomputer 28. Similarly, the two output terminals 1Y and 2Y of the data selector 24 are connected. Are connected to the input terminal of an RS flip-flop composed of NAND gates 25 and 26 such as 74HC00, respectively, and the output terminal of the NAND gate 26 is connected to the P1 port of the microcomputer 28.
[0014]
FIG. 6 is a time chart showing the operation state of the block circuit diagram of FIG. 5. In order to identify the rotor 2, the rotor 2 is rotated by an operator's hand or the rotation of the motor 7 to recognize the presence / absence and position of the magnet 6. When the microcomputer 8 performs the operation, as shown by (a) and (b) in the figure, when the inverted signal of the two-phase signal of the rotary encoder 8 is input from the Schmitt trigger inverters 17 and 18 to the flip-flop 19, the rotor 2 is turned to the clock. When the direction is rotated, a logic Q level signal of the clock Paris width of the oscillator 20 is output every time an edge of a two-phase signal appears from the 1Y output terminal of the data selector 24 (FIG. 6D). At this time, the 2Y output of the data selector 24 is Since the logic “1” level is maintained (FIG. 6D), the interrupt is input to the interrupt input terminal iRQ of the microcomputer 28 by the exclusive OR 27. Rolling signal (Fig. 6 g) is sent, whereas P1 port input signal (Fig. 6 e) becomes a signal indicating the rotational direction of the rotary encoder 8, a logic "0" level is sent in this state. The P0 port input signal (FIG. 6) is an output signal of the magnet sensor 4, and when the presence of the magnet 6 is detected, logic “1” is sent to the P0 port of the cpu 28.
[0015]
FIG. 7 shows a processing flowchart when the microcomputer 28 recognizes the arrangement pattern shown in FIGS. 3 and 4 based on the signals of the input ports P0, P1, and iPQ and determines the identification code. 5, a predetermined processing procedure is written in a storage device indicated by a ROM 29. In FIG. 7, a process 101 is a process for executing initialization of the signal storage memory (hereinafter referred to as RAM) 30 of the magnet sensor 4 in the CPU 28. Referring to FIG. If the number of output pulses per rotation of the encoder 8 is 120 pulses / rotation, for example, the resolution is 480 pulses, which is four times that, so the memory in the range from 1 to N of 48 addresses is filled with “F”. After that, when the signal from the encoder 8 is input to the iRQ input terminal after the microcomputer 28, the interrupt process is executed at the falling edge.
[0016]
When an interrupt occurs now, the signal input state of the P1 port is checked by the interrupt processing judgment 111. If the logic is “Lo”, the rotor 2 is rotating in the clockwise direction. The signal storage destination address is incremented by +1, and if the address so far is n, it becomes n + 1 and the process proceeds to decision 114. Similarly, when the rotor 2 is rotating counterclockwise in the determination 111, the P1 port input becomes logic “Hi” and the process proceeds to step 113, where the signal storage destination address of the magnet sensor 4 is decremented by −1. If the address up to n is n−1, the process proceeds to decision 114. In decision 114, if the magnet sensor 4 senses the presence of the magnet 6, the input logic of the P8 port of the microcomputer 28 becomes "Hi", so that the process proceeds to process 115, and the process of writing "1" at address n + 1 is executed in the example of the RAM 30. On the other hand, if the magnet sensor 4 does not detect the presence of the magnet 6 in the determination 114, the process proceeds to a process 116, and a process of writing "0" according to the storage destination address indicated in the RAM 30 is executed. Note that if the instruction address before increment is already N in the process 112, the process is set to 1, and at the same time, if the instruction address before decrement is 1 in the process 113, the process is set to N.
[0017]
Judgment 103 indicates that the rotation of the rotor 2 has made a complete rotation, and the data “F” in the RAM 30 has been replaced with “0” or “1” from address 1 to address N, and preparation for generating the rotor 2 identification code is complete. It is for judgment. In the process 104, there is a process for establishing the arrangement pattern of the magnets 6 of the rotor 2, and if "1" continuous with the data in the memory from the addresses n-3 to n + 3 of the RAM 30 in FIG. 8 is an example, the lattice point d in FIG. If the rotor 2 is rotating counterclockwise in the same manner in the determination 111, the P1 port input becomes logic “Hi” and the process proceeds to step 113 where the signal stored in the magnet sensor 4 is stored. -1 dexment of the address is executed, and if the previous address is n, it becomes n-1 and proceeds to decision 114. The size of the address obtained by dividing the number of addresses from 1 to N by the number of grid points divided at equiangular intervals is defined as the pitch of the grid points, with this central address n indicated by A as the reference of the grid points. Therefore, in this embodiment, the 480 address / 12 grid point has a 40 address pitch, and the data in the memory 30 obtained from the RAM 30 at this pitch can be recognized as the presence / absence of the magnet 6 on the grid point. An identification code consisting of 12 bits “1” and “0” representing the first to third nibbles is obtained. A process 105 is a process for checking the compatibility between the classification code and the check code. The process 106 is a process for establishing an identification code. In the case of the arrangement pattern of the magnet 6 shown in FIG. 2, the rotor 2 is identified as the classification code “1B” and the check code “D”. The maximum rotation speed, temperature control coefficient, operating conditions, etc. are read in accordance with a database previously written in the ROM 29. In the case of an identification code that is not in the database written in the ROM 29 due to a part of the magnet 6 missing or the like, an error can be displayed and the operator can be made.
[0018]
As described above, in the specific embodiments of the present invention, the magnet is used as the identifier, and the identifier detection sensor is described as an example using the magnet as the magnet sensor, but the present invention is not limited to this. It is apparent from the idea of the present invention that a photodetection element such as a phototransistor can be used as the identifier detection sensor, or that a shape or unevenness can be used as the identifier and a proximity sensor or the like can be used as the identifier detection sensor.
[0019]
Further, in the present invention, the case where there is one magnet sensor 4 that needs to rotate the rotor 2 by one rotation or half-clockwise rotation in order to identify the rotor 2 is described. In order to reduce the rotation angle for identification, the number of the magnet sensors 4 is increased at equal angular intervals so that a plurality of magnet sensors 4 are arranged around the rotation axis of the rotor 2. If the output is input to the microcomputer 28, the storage address of the magnet signal in the RAM 30 can be determined corresponding to each magnet sensor by correcting the position of the magnet sensor to the position output signal of the rotary encoder 8. It does not depart from the idea of the present invention. In this case, a connector having a multi-pole hermetic seal function is required, but it is obvious that the connector can be configured more easily than before if the number of poles is suppressed to a certain number.
[0020]
Further, in order to obtain the arrangement pattern of the magnet 6 without rotating the rotor 2, the magnet sensor 4 is rotated around the rotation axis of the rotor 2 without rotating the magnet 6, and at this time, the appropriate rotation of the magnet sensor 4 is performed. It is also possible to provide an encoder for detecting the angle and detect the arrangement pattern of the magnets 6.
[0021]
Further, as the rotary encoder 8 serving as an angle detector, a resolver, a potentiometer or the like capable of detecting an angle can be used.
[0022]
Another embodiment to which the embodiment of the present invention is applied will be described below.
[0023]
FIG. 9 shows an application example in which a rotor identification device of a centrifuge according to the present invention is combined with another rotor identification device different from that of the present invention in order to prevent the rotor from over-rotating against a single failure of any part. 1 are denoted by the same reference numerals, and other rotor identification devices different from those described above for the rotor 2 are the same as those described in JP-A-06-198219. It is. At the center of the rotation axis of the rotor 2, an identifier 31 such as a magnet and an identifier detection sensor 32 including a magnetic sensor such as a Hall element and a magnetoresistive element for detecting the identifier 31 are provided at an angle θ. A signal is sent to a control device 35 outside the rotor chamber 1 by a signal line 34 through a seal 33.
[0024]
FIG. 10 is a cross-sectional view taken along the line AA in FIG. 9, and parts having the same functions as those in FIG. FIG. 11 shows a state of a signal output to the signal line 34 when the rotor 2 is rotating. The control device 35 incorporating the microcomputer has a pulse output period T, The maximum rotational speed RMAX calculated from the actual rotational speed RRP, the type code iRQ, and the type code of the rotor 2 is calculated from TH and TL. When it is determined that the actual rotational speed and the RRPM exceed the maximum allowable rotational speed RMAX1, the control line A shut-off signal is output to the first shut-off device 38 via 37, and the shut-off device 38 is operated to disconnect the motor from the power source 36. In FIG. 9, 36 is a power source such as an AC power source, 39 is a motor drive device such as an inverter, 41 is a motor 7 energy supply line connecting the motor 7 and the motor drive device 39, and 38 and 40 are motor 7 These are a first shearing device and a second shearing device arranged in series with each other with respect to the rotational energy supply path. The control device 46 includes a function for identifying the rotor 2 of the control device 11, and further has a function for controlling the rotational speed of the motor 7 and a function for preventing the rotor 2 from over-rotating. The actual rotational speed is measured and grasped, a control signal is output to the motor drive device via the control line 42 to control the motor 7 at a predetermined rotational speed, and the rotor 2 is identified from the magnet sensor 4 and magnet 6 of the rotor 2. If it is determined that the rotor 2 has exceeded the maximum allowable rotational speed RMAX2 (equivalent to the maximum allowable rotational speed RMAX1) of the rotor 2 obtained from the result of the above, the second shearing device is shut off via the control line 43. A signal is output to disconnect the motor 7 from the motor drive device 39.
[0025]
【The invention's effect】
According to the present invention, an identifier is arranged on lattice points at equiangular intervals around the rotation axis of the rotor, the identifier is arranged so that the presence or absence of the identifier is a code pattern, and the identifier detection sensor detects the presence of the identifier. An angle detector that detects the relative angle of the rotation of the rotor of the identifier and the rotor of the identifier detection sensor is provided, and the identifier arrangement pattern is read from the signal output of the angle detector and the signal output of the identifier detection sensor. The identification code shown is composed of a classification code and this classification code check code, or as an identifier on an equiangularly spaced lattice point on the same circumference around the rotation axis of the rotor. As an identifier detection sensor that detects the presence of this magnet, for example, a magnet sensor such as a hol element An encoder is provided as an example of an angle detector for detecting the rotation angle of the magnet and the magnet sensor, and an identification device is provided for identifying and identifying the magnet arrangement pattern from the encoder signal output and the magnet sensor signal output. Since the pattern is composed of a classification code and a sum check code according to this classification code example , the rotor can be identified with a minimum number of identifier detection sensors, and at the same time, identification errors can be eliminated as much as possible. The reliability of identification can be improved.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional side view of a rotor identification device for a centrifuge according to the present invention.
FIG. 2 is an arrangement pattern diagram of magnets 6;
FIG. 3 is a diagram showing an arrangement pattern of magnets 6 with different readout positions.
FIG. 4 is a diagram showing other arrangement patterns of magnets 6 with different readout positions.
FIG. 5 is a block circuit diagram showing a specific example of the control device 11;
FIG. 6 is a time chart showing an operation state of the block circuit diagram.
FIG. 7 is a diagram showing a processing flowchart of the microcomputer 28;
FIG. 8 is a diagram exemplifying a memory storage state of a magnet signal.
FIG. 9 is a diagram showing an application example of the present invention.
10 is a cross-sectional view taken along line AA in FIG.
FIG. 11 is a diagram illustrating a state of a signal output in one rotation while the rotor 2 is rotating.
[Explanation of symbols]
2 is a rotor, 4 is an identifier detection sensor, 6 is an identifier, 8 is an angle detector, and 11 is a control device.

Claims (2)

A motor, a rotor that rotates by the rotational force of the motor, an identifier that is arranged on lattice points at equiangular intervals around the rotation axis of the rotor, and an identifier that detects the presence or absence of the identifier A centrifuge having a detection sensor, an angle detector for detecting the rotation angle of the identifier and the identifier detection sensor, and a control device for identifying an arrangement pattern of the identifier from a signal output of the angle detector and a signal output of the identifier detection sensor The centrifuge characterized in that the arrangement pattern of the identifier is composed of a part indicating the classification of the rotor and a part for checking a part indicating the classification of the rotor. The arrangement pattern of the identifier includes a first code and a second code, and the second code follows the first code according to a predetermined procedure and a third code derived by the control device. The centrifuge according to claim 1, wherein the centrifuges are configured to coincide with each other.

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