JPS6313745B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control circuit for a centrifuge, and particularly to a control circuit suitable for improving the reliability and maintainability of a centrifuge that operates a zonal rotor that performs sample injection and extraction during rotation. It is related to.

Microcomputer (hereinafter referred to as microcomputer)
In this type of centrifugal machine that does not use the zonal rotor, the driving circuit of the zonal rotor is made of hard logic, which is complicated and has many components, resulting in high costs. Furthermore, since the circuit is complicated, it has been difficult to significantly improve reliability and maintainability.

For this reason, microcomputer-based centrifuges have recently become mainstream, but they require little hardware, control sequences using software, and are highly reliable.
There is a strong demand for something that is easy to maintain, easy to operate, and low in cost. In addition, the rotation speed suitable for zonal rotor injection and extraction of samples is said to be approximately 3000 rpm, but 3000 rpm is not necessarily appropriate for installing caps for injection and extraction and for sample separation.
It is required to be able to make it variable.

The present invention has been made in view of the above, and its purpose is to provide a centrifugal system using a microcomputer that can control the sequence using software, reduce the amount of hardware required, and improve reliability and maintainability. The goal is to provide a control circuit for the machine.

The present invention is characterized by: a rotation detector that detects the rotation of the electric motor that drives the zonal rotor; a rotation speed setting device that sets the zonal rotation speed of the zonal rotor and the high-speed separation rotation speed during separation; A start switch that is turned on when starting rotation and moving to high-speed rotation during separation, a stop switch that is turned on when ending centrifugation, and a zonal switch that is turned on when starting zonal operation and turned off when zonal operation ends. and,
A door switch that turns on when the centrifuge door is closed, a door lock solenoid that locks the door in its closed state, and a thyristor circuit that controls the electric power supplied to the motor to control the operation of the motor. and the on/off information of the start switch, stop switch, zonal switch, and door switch, the setting information of the rotation speed setting device, and the motor speed from the rotation detector, and when the start switch is turned on for the first time, the zonal switch is turned on. the rotation speed of the zonal rotor is accelerated and stabilized to the zonal rotation speed set by the rotation speed setting device when the zonal switch is turned on and the stop switch is turned on. output signal to accelerate and settle the rotational speed of the zonal rotor to the separation rotational speed set by the rotational speed setting device when the start switch is turned on while the zonal rotor is rotating at the zonal rotational speed; an output signal that turns off the door locking solenoid when the rotational speed of the zonal rotor rises to a zonal appropriate rotational speed that is slightly higher than the zonal rotational speed; The present invention also includes a microcomputer that generates an output signal that turns on the door locking solenoid when the door locking solenoid is turned on.

The present invention will be described in detail below with reference to the embodiment shown in FIG. 1 and FIG. 2.

FIG. 1 is a block diagram showing one embodiment of a control circuit for a centrifuge according to the present invention. 1 is an electric motor that drives the zonal rotor 17 that performs sample injection and extraction during rotation; 2 is a rotation detector that detects the rotation of the electric motor 1;
3 is a thyristor circuit, 4 is an output port, 5 is a door lock solenoid, 6 to 8 are a microcomputer's central processing unit (CPU), read-only memory (ROM), random access memory (RAM), 9
is a backup battery, and motor 1 has a CPU
Necessary power is supplied by controlling the thyristor circuit 3 using a signal outputted from the thyristor circuit 6 via the output port 4.

On the other hand, the CPU 6 has the following information via the input port 10:
A start switch 11 that is turned on when starting the rotation of the electric motor 1 and when moving to high speed rotation during centrifugation, a stop switch 12 that is turned on when ending the centrifugation, and a stop switch 12 that is turned on when starting zonal operation and turned off when zonal operation is finished. The on/off information of each switch such as the zonal switch 13 and door switch 14 and the output signal of the rotation detector 2 are input, and the output signal of the rotation speed setting device 15 that sets the rotation speed of the electric motor 1 is input to the A-D converter 16.
is entered via.

The zonal switch 13 is turned on when operating the zonal rotor 17, and when the zonal rotation speed is set, it can be operated with the door open, but when it is off, it becomes a normal centrifuge control circuit.
When the door is opened, it cannot be rotated.

The CPU 6 receives each input signal and stores software programs and software data.
It performs information processing together with the ROM 7 and the RAM 8 that stores data, and outputs necessary signals to the thyristor circuit 3 via the output port 4.

The door is locked by a door lock solenoid 5 by a signal output from the CPU 6 through the output port 4.
It can be opened and closed by operating the .

FIG. 2 is a time chart showing the operation mode for explaining the operation of FIG.
The operating states of the stop switch 12, door lock solenoid 5, and door switch 14 are shown.

Next, the operation shown in FIG. 1 will be explained with reference to FIG.

The rotational speed of the zonal rotor 17 suitable for sample injection and extraction is approximately 3000 rpm;
Let be the zonal rotation speed. Further, a rotation speed slightly higher than the zonal rotation speed will be described as a zonal appropriate rotation speed. Note that the door must be opened when injecting and extracting samples. Therefore, when the zonal switch 13 is in the on state and the zonal rotation speed is below the appropriate zonal rotation speed, the door lock solenoid 5 is turned on so that the door can be opened and closed. and,
When the actual rotation speed exceeds the zonal appropriate rotation speed,
The door lock solenoid 5 is turned off to lock the door. That is, the door lock solenoid 5 is designed to lock the door when it is turned off.

When starting from a stopped state when the zonal switch 13 is on, the software program is such that the start switch 11 cannot be turned on unless the rotation speed set in the rotation speed setting device 15 is below the zonal appropriate rotation speed.

When a rotation speed below the zonal appropriate rotation speed is set in the rotation speed setting device 15, the start switch 11 can be turned on, the set rotation speed at that time is stored in the RAM 8 as the zonal rotation speed, and at the same time, the rotation speed is changed to that rotation speed. Acceleration settling is performed by the CPU 6.
Then, when shifting to zonal rotation, even if the rotation speed set in the rotation speed setting device 15 is changed, the rotation speed is maintained at the previously set rotation speed.

Further, even if the stop switch 12 is turned on, the rotation speed is maintained at the zonal rotation speed without stopping. When the sample injection is finished and the rotation starts at high speed, the door is closed, the door switch 14 is turned on, and then the start switch 11 is turned on again.The setting of the zonal rotation speed is canceled and a new value is set in the rotation speed setting device 15. Accelerates and settles to the set value.

When moving to high-speed rotation, turn on the start switch 11 with the door open, and the door switch 1
4 is off, when the actual rotational speed exceeds the appropriate zonal rotational speed, a stop signal is automatically input and control is made to return to the zonal rotational speed again. Thereafter, when the rotation speed reaches the high speed set by the rotation speed setting device 15 and centrifugation of the sample is completed, the stop switch 12 is turned on. As a result, the electric motor 1 decelerates, and when it decelerates to the appropriate zonal rotation speed, the door is unlocked and can be opened and closed.
Further, the electric motor 1 is set to the zonal rotation speed stored in the RAM 8.

To stop the zonal rotor 17 after the electric motor 1 reaches the zonal rotation speed and sample extraction is performed, the zonal switch 13 is turned off. At this time, the zonal rotation speed stored in the RAM 8 is erased by the zonal switch-off signal, and the electric motor 1 is decelerated and stopped.

Here, if the zonal switch 13 is on and a power outage occurs while the zonal rotor 17 is rotating, the stored contents of the RAM 8 are retained by the power supplied from the backup battery 9. Therefore,
When the power is restored, if the zonal rotor 17 rotates at a speed equal to or higher than the zonal rotation speed, the rotation speed is set to the zonal rotation speed and maintained at that rotation speed.

As described above, according to the embodiment of the present invention, when injecting and extracting a sample, the zonal rotor 17 is held at the zonal rotation speed, and when the rotation starts, the rotation speed setting device 15 indicates that the zonal rotor 17 is rotating at a zonal rotation speed below the appropriate zonal rotation speed. Centrifugation cannot be started unless the number is set, and when moving to high-speed rotation for sample separation, the centrifugation will not shift to high-speed rotation even if the start switch 11 is turned on unless the door is closed and the door switch 14 is turned on. The operability and reliability of the machine can be improved. Furthermore, when the zonal rotation speed reaches the appropriate zonal rotation speed during acceleration, the door lock solenoid 5 turns off and locks the door, and when the zonal rotation speed reaches the appropriate zonal rotation speed during deceleration, the door lock solenoid 5 turns on and the door lock is released, thereby improving maintainability. can be improved. Moreover, since all operation control of the zonal rotor 17 is performed by a microcomputer, the hardware configuration is simplified. Furthermore, since the zonal rotation speed can be set arbitrarily to the rotation speed setting device 15, the operability is also improved by this.

In the embodiment shown in FIG. 1, the rotation speed setter 15 is used to set the zonal rotation speed and the high speed rotation speed during sample separation, but the A-D converter 16 is configured to set another zonal rotation speed. A speed setting device may be provided, in which the zonal rotation speed can be set, and in the rotation speed setting device 15, a high speed rotation speed can be set. In this case, the rotation can be controlled by the newly installed zonal rotation speed setting device when injecting and extracting the sample, and the rotation can be controlled by the rotation speed setting device 15 during high-speed rotation, so the backup battery 9 is not required. .

As explained above, according to the present invention, the operation control of the zonal rotor is performed by software using a microcomputer, and the zonal rotation speed holding function and the zonal rotation speed variable function are provided, so that the hardware can be easily configured. Moreover, there is an effect that operability, reliability, and maintainability can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of a control circuit for a centrifuge according to the present invention, and FIG. 2 is a time chart showing operating modes for explaining the operation of FIG. 1. In the figure, 1 is a motor, 2 is a rotation detector, and 3
is the thyristor circuit, 4 is the output port, 5 is the door lock solenoid, 6 is the CPU, 7 is the ROM, and 8 is the
RAM, 9 is a backup battery, 10 is an input port, 11 is a start switch, 12 is a stop switch, 13 is a zonal switch, 14 is a door switch, 15 is a rotation speed setting device, 16 is an A-D converter, and 17 is a zonal rotor. .

Claims (1)

[Claims] 1. After injecting the density gradient liquid and the separated sample into the zonal rotor rotating at a predetermined low speed and zonal rotation speed, the zonal rotor is rotated at a predetermined high separation speed to perform centrifugal separation. In a centrifuge that performs zonal operation by extracting a separated liquid from the zonal rotor while the zonal rotor is decelerated to the zonal rotation speed again, a rotation detection unit detects rotation of an electric motor that drives the zonal rotor. a rotation speed setting device for setting the zonal rotation speed of the zonal rotor and the high-speed separation rotation speed during separation; and a start switch that is turned on when starting the rotation of the electric motor and when moving to high-speed rotation during separation. , a stop switch that is turned on when the centrifugation ends, a zonal switch that is turned on when the zonal operation starts and is turned off when the zonal operation is finished, a door switch that is turned on when the door of the centrifuge is closed, and a door switch that is turned on when the door of the centrifuge is closed; a door lock solenoid for locking the door in the closed state; a thyristor circuit for controlling the operation of the motor by controlling the electric power supplied to the motor; and the start switch, stop switch,
Taking as input the on/off information of the zonal switch and the door switch, the setting information of the rotation speed setting device, and the motor speed from the rotation detector, and determining whether or not the zonal switch is on when the start switch is turned on for the first time, an output signal that accelerates and stabilizes the rotational speed of the zonal rotor to the zonal rotational speed set by the rotational speed setting device when the zonal switch is on and when the stop switch is turned on; an output signal that accelerates and settles the rotational speed of the zonal rotor to the separation rotational speed set by the rotational speed setting device when the start switch is turned on while the zonal rotor is rotating at the zonal rotational speed; An output signal for turning off the door locking solenoid when the rotational speed increases to a zonal appropriate rotational speed slightly higher than the zonal rotational speed, and an output signal for turning off the door locking solenoid when the rotational speed of the zonal rotor falls from the separation rotational speed to the zonal appropriate rotational speed. A control circuit for a centrifuge, comprising: a microcomputer that generates an output signal to turn on a solenoid. 2. Control of a centrifuge according to claim 1, characterized in that the rotation speed initially set in the rotation speed setting device is a zonal rotation speed suitable for injection and extraction of a sample from the zonal rotor. circuit.