JP2003135994A - Centrifugal separator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve time loss and operators load by enabling to decide wether it is abnormal case or a case that a rotor is not loaded when the number of rotation becomes zero for a short time in the deceleration even if the operators mistake the handling. SOLUTION: Because the acceleration time in the case that the rotor 13 is not loaded is shorter than the acceleration time in the case that the rotor 13 is loaded, the change of the number of rotation in the acceleration is checked and when the change of the rotation is larger than a fixed value, it is decided that the rotor 13 is not loaded and a memory that the rotor 13 is not loaded is set. When abnormality that the number of rotation becomes zero during the operation occurs and when the difference from the previous number of the rotation is equal to or above a fixed value and the memory that the rotor 13 is not loaded is set, it is controlled to decide that the normal operation is carried out. If the memory that the rotor 13 is not loaded is not set, it is controlled to generate an alarm.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a centrifugal separator which freely attaches and detaches a rotor on which a sample to be set is set, and accelerates and rotates to a desired rotational speed in a short time. This is related to processing when such a device is not mounted on a rotor. 2. Description of the Related Art A centrifugal separator of this kind is operated by a user who determines so-called separation conditions such as the number of revolutions, the operation time (separation time), and the holding temperature in accordance with the sample. It is a feature of centrifuges to use large and small rotors according to the type and amount of sample to be handled. In order to effectively utilize the user's time, it is possible to accelerate and decelerate in a short time by increasing the power of the motor and performing optimal control. As a safety measure, the doors are locked during rotation and controlled so that no hands can enter. On the other hand, consideration is given to releasing the door lock at the same time as the stop of the rotor so that the user can effectively use the time. [0003] During the rotation of the rotor, the door is unlocked and the door is opened. When the door is opened, the user feels anxiety due to the wind and sound in the rotating chamber. If something gets in your hand or something enters it, an unexpected accident will occur in the rotating rotor. The detection of the number of rotations is an important function, and when the rotation signal is abnormal, the rotation is decelerated and stopped. But,
It is unclear whether or not the motor has stopped, and users are uneasy.If a signal generator for discriminating the rotor is provided, it is determined that the rotation has stopped based on the rotor discrimination signal. By assigning the time, the time until the stop is secured, and the unlocking of the rotating door is prevented from being released. This fixed time is assigned a time until a rotor having no signal generator for rotor determination stops. However, when the rotor is operated without a rotor, both the acceleration and the deceleration are short because the load is small, and the rotation speed becomes 0 from a certain rotation speed or more at the time of deceleration stop. Therefore, a door lock condition occurs for a certain period of time, and the user has to wait for the door lock to be released. [0004] As described above, unlocking the door during rotation is an important matter for ensuring the safety of the user. On the other hand, when the vehicle is operated without the rotor mounted thereon. Is operated in a short time for both acceleration and deceleration because the load is small. Due to the control timing, the detection of the rotational speed has time. During this time, when the number of rotations became 0, it was not possible to determine whether the rotation was stopped normally or the rotation signal was abnormal, and the door lock could not be released for a certain time as an alarm. An object of the present invention is to pay attention to the fact that the acceleration time when the rotor is not mounted is short, and during acceleration, the present measured rotational speed is compared with the previous measured rotational speed, and it is determined that the acceleration is short-time due to light load. In such a case, it is determined that the rotor is not mounted, and is stored. As a result, even if the number of rotations decreases during deceleration stop, when it can be determined that the operation is performed without mounting the rotor, it can be treated as normal, and the burden on the user can be greatly improved. A centrifugal separation rotor having a signal generator for rotor identification, a drive shaft for rotating the centrifuge rotor, a motor for applying a rotational force to the drive shaft, and a motor A function to measure the number of rotations by processing a signal from the signal generator and a signal from the rotation signal generator, a function to determine the rotor, a door to lock when rotating, and a door to stop when rotating. A mechanism for releasing the lock.
In the centrifuge that determines that the rotation signal is abnormal and issues an alarm when it detects an error, there is no signal input to the rotor signal generator during acceleration, and the rotation measurement value from the rotation signal exceeds a certain value compared to the previous measurement value. This is achieved by determining that the rotor is not mounted and determining that the vehicle is stopped even when detecting a rotation speed 0 from a certain rotation speed or higher during deceleration, and releasing the door lock. The preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a block diagram showing a centrifuge according to the present embodiment, FIG. 2 is a flowchart showing a check of the absence of a rotor during acceleration and a graph showing an acceleration state according to the present embodiment, and FIG. 3 is a rotational abnormality during deceleration according to the present embodiment. FIG. 4 is a flow chart relating to the check, FIG. 4 is a partial longitudinal side view showing the centrifugal separator according to the present embodiment, and FIG. As shown in FIGS. 1 and 4, a user puts a sample into a test tube 14, inserts the sample into a rotor 13, and
5, the door 18 is closed, and the start switch 19 provided in the operation / display unit 17 is turned on to rotate. The rotation signal generator 16 generates a signal corresponding to the rotation. The control device 1 controls the drive device 15 so that the signal processing unit 4 performs stable control at the rotation speed set from the operation / display unit 17. On the other hand, the signal of the rotor discrimination signal 2 of the rotor 13 is
The signal is input to the signal processing unit 4 via the rotor determination signal interface 3. A fixed number of signals are input to the signal of the rotor discrimination signal device 2 with respect to the signal of one rotation of the rotation signal generator 16. 36 rotation signals are generated per rotation. In the example of the rotation signal and the rotor discrimination signal shown in FIG. 5, the signal processing unit is configured to input nine signals per rotation through a waveform shaping / frequency dividing circuit. On the other hand, four rotor discrimination signals are generated per rotation. Although the details of the rotor determination method are not described, the configuration is such that the angle between the signals is calculated, and the determination is made from the data stored in the storage element.
As shown in the flowchart of FIG. 2, a check is performed based on the presence or absence of a rotor determination signal during acceleration. When the rotor discrimination signal is input, the process is normally terminated because the rotor is mounted. If there is no rotor discrimination signal, the rotation speed is calculated. This value is compared with the previous calculated value of the number of revolutions, and when the value is equal to or more than a certain value, it is determined that there is no rotor, and "no rotor mounted" is stored in the storage element. On the other hand, as shown in the flowchart of FIG. 3, when the rotational speed is calculated to be 0 during deceleration, if the previous rotational speed is lower than a certain value, it is determined that the engine has stopped normally. None Check the memory to determine whether the rotation signal is abnormal or if the rotor is not mounted for a short time and set the door lock time in the storage element so that the door lock cannot be released for a specific time. . When the vehicle is not decelerating, the same determination is made. However, if the previous rotation speed is higher than a certain value regardless of the presence or absence of the rotor, it is determined that the rotation is abnormal, the operation is stopped, and the door lock time is stored in the storage element. set. When the rotation speed is equal to or lower than the predetermined rotation speed, the control is continued so that the rotation speed becomes the set rotation speed. According to the present invention, when the vehicle is driven without a rotor, the vehicle is accelerated for a short time due to a light load.
It can be detected. Thus, even if the user mishandles the vehicle, even if the number of revolutions becomes 0 in a short time during deceleration, it is possible to determine whether an abnormality has occurred or the rotor is not mounted, so that correct operation is continued. Therefore, it is possible to reduce the time loss and the burden on the user.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a centrifuge according to the present invention. FIG. 2 is a flowchart illustrating a rotor mounting absence check during acceleration according to the present invention and a graph illustrating an acceleration state. FIG. 3 is a flowchart relating to a rotation abnormality check during deceleration according to the present invention. FIG. 4 is a partially longitudinal side view showing a centrifuge according to the present invention. FIG. 5 is a time chart illustrating an example of a rotation signal and a rotor determination signal according to the present invention. [Description of References] 1 is a control device, 2 is a rotor discrimination signal generator, 3 is an interface, 4 is a signal processing unit, 5 is a storage element, 11 is a centrifuge housing, 12 is a rotating chamber, 13 is a rotor, 14 is a test tube, 15 is a driving device, 16 is a rotation signal generator, 17 is an operation / display unit, 18 is a door, 19 is a start SW, 20
Denotes a stop SW, 21 denotes a rotation speed display unit, and 22 denotes a door lock mechanism.

Claims (1)

Claims: 1. A centrifuge rotor having a signal generator for rotor identification, a drive shaft for rotating the centrifuge rotor, a motor for applying a rotational force to the drive shaft, A rotation signal generator associated with the rotation of the motor, a function of processing a signal from the signal generator and a signal from the rotation signal generator to measure the number of rotations, a function of determining the rotor, and a door lock during rotation And a mechanism for releasing the door lock when stopped, and when a rotation speed 0 is detected from a certain rotation speed or more, in a centrifugal separator that determines that the rotation signal is abnormal and issues an alarm, If there is no signal input and the rotation measurement value from the rotation signal is more than a certain value with respect to the previous measurement value, it is determined that the rotor is not mounted, and the rotation speed is reduced from a certain rotation speed to 0
A centrifugal separator characterized by judging that a stop has occurred even when detecting a state, and releasing the door lock.