JP6324831B2 - Radiation measurement equipment - Google Patents

Description

  The present invention relates to a radiation measuring apparatus, and more particularly to control for restarting the apparatus when a power failure occurs and when the power failure is restored.

  In a liquid scintillation counter that is a radiation measuring apparatus, a radioactive sample is housed in a sample container together with a liquid scintillator, and radiation emitted from the sample is detected as light emitted from the scintillator by a photomultiplier tube or the like. A number of sample containers are set in the radiation measuring apparatus, and the sample containers are sequentially sent to measure the radiation for each sample container. In addition, a plurality of measurements may be performed on a single sample at intervals. By measuring a large number of samples, or by measuring a single sample a plurality of times, the measurement may take a long time, for example several days, during which time the radiation measuring device is automatically operated.

JP-A-11-31678

  It is desirable that the measurement is temporarily interrupted when a power failure occurs during the automatic operation of the radiation measuring apparatus, and then the measurement is resumed when the power supply is restored (recovered). Normally, when the power supply is resumed, the control unit of the radiation measurement apparatus operates to start operation based on the rise of the power supply. However, if there is a power recovery during shutdown processing based on the occurrence of a power failure, power supply has already been performed at the time of completion of the shutdown processing, and power supply will not start up and operation may resume. Can not.

  It is an object of the present invention to provide a radiation measurement apparatus that can be reliably restarted when a power failure is restored.

  The radiation measurement apparatus according to the present invention is one of a power supply unit that supplies electric power from the outside to each operation unit of the radiation measurement device and an operation unit of the radiation measurement device, and controls the other operation units. The control part to perform and the relay which cuts off the electric power sent to the central processing part of a control part from a power supply part are included. The power supply unit supplies power from the auxiliary power supply to some operating units when power from the outside is interrupted. The control unit includes a central processing unit, and power is supplied from the auxiliary power source to the control unit for a predetermined period in the event of a power failure.

  When a power failure occurs, the central processing unit starts a shutdown process. When power is restored during the shutdown process, the relay is turned on after being turned off for a predetermined time after completion of the shutdown process. When the relay is turned on from off, the central processing unit is activated.

  If the power failure continues even after the shutdown process is completed, the power supply from the auxiliary power supply is stopped.

  When the relay is turned off after completion of the shutdown process, the power supply is interrupted again. If the power outage continues even after the period when the relay is turned off, the power supply from the auxiliary power supply is stopped. When power is restored during the same period, the relay is turned on after a predetermined time has elapsed since the relay was turned off.

  A specific example of the operation at the time of power failure is as follows. When power from the outside is interrupted (when a power failure occurs), the power supply unit supplies power from an auxiliary power source included in the power supply unit to the control unit, and transmits a power failure detection signal indicating the occurrence of a power failure. When the control unit, particularly the central processing unit, receives the power failure detection signal, it starts the shutdown process. When the shutdown process is completed, the control unit instructs the power supply unit to stop the power supply from the auxiliary power supply, and the radiation measuring apparatus is stopped. When power is restored, the power supplied to the control unit, particularly the central processing unit, changes from off to on, and the central processing unit is activated based on the rise of the supplied power. After the start-up process is completed, the operation of the radiation measuring apparatus is resumed so as to continue the process stopped by the power failure.

  When power is restored before the shutdown process of the central processing unit is completed, the power supply unit transmits a power recovery detection signal indicating that power has been restored to the control unit. When the shutdown process is completed, the control unit that has received the power recovery detection signal turns the relay on after turning it off for a predetermined time. When the relay is turned off and on, the power supplied to the central processing unit rises, and the central processing unit is activated based on this. After the start-up process is completed, the operation of the radiation measuring apparatus is resumed so as to continue the process stopped by the power failure.

  If a power failure occurs again during the relay off period after the shutdown process is completed, the power supply sends out a power failure detection signal.If the power failure continues after the relay off period ends, the control unit that received this power failure detection signal An instruction is given to stop power supply from the auxiliary power supply, and the radiation measuring apparatus is stopped. Also, if a power failure occurs during the relay off period and power is restored during the same period, the control unit turns on the relay after a predetermined time has elapsed since the relay turned off based on the power recovery detection signal from the power supply unit. To.

  Even when power is restored during the shutdown process of the central processing unit due to a power failure, the operation of the radiation measuring apparatus can be resumed. Moreover, after a shutdown process, when a power failure occurs again in the period when the relay is OFF, the power supply by the power supply unit can be stopped.

It is a block diagram which shows the principal part structure of the radiation measuring device of this embodiment. It is explanatory drawing regarding the electric power supply at the time of a power failure. It is a flowchart regarding the time of a power failure of the radiation measuring apparatus of this embodiment. It is a flowchart regarding the time of a power failure of the radiation measuring apparatus of this embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a main configuration of the radiation measuring apparatus 10. The radiation measuring apparatus 10 is an apparatus that measures the radiation dose of a sample using a liquid scintillator. A sample to be measured is stored in a sample container together with a liquid scintillator. The scintillator emits light due to the radiation emitted from the sample. The measuring unit 12 is provided with a photomultiplier tube, which detects the light emission of the scintillator. The sample containers containing the samples are sequentially sent to the measuring unit 12 by the sample changer 14, and the sample containers that have been measured are collected in the sample changer 14. A plurality of sample containers, for example, 300 to 400 sample containers are set in the sample changer 14 at a time, and the sample changer sends the set sample containers one by one to the measurement unit, and collects the sample containers that have been measured. There may be a case where a plurality of measurements are performed with a time interval for one sample container. That is, the measurement is performed once for each of the plurality of sample containers, and after all the measurement is completed, the measurement is performed again or repeatedly.

  The operations of the measurement unit 12 and the sample changer 14 are controlled by a control unit including a central processing unit 16 and a programmable logic controller (hereinafter referred to as PLC) 18. The central processing unit 16 can be configured as a CPU board on which a CPU (central processing unit) is mounted, and controls the operation of the measuring unit 12 to acquire measured data. The acquired data is stored in the storage unit 20 such as a hard disk drive. The PLC 18 controls the operation of the sample changer 14 via an interface board (hereinafter referred to as an IF board) 22 based on a command from the central processing unit 16. The PLC 18 controls the operation of each mechanism of the sample changer 14. For example, the rack is fed by controlling a drive motor of a rack feeding mechanism that feeds a rack on which a plurality of sample containers are mounted. In addition, one sample container is taken out from the rack, supplied to the measuring unit 12, and a drive motor of a container supply / recovery mechanism that recovers the measured sample container from the measuring unit 12 is controlled. A signal of a sensor for detecting the position of the rack in the sample changer 14 and the position of the sample container is transmitted to the PLC 18 via the IF board, and the operation timing of each mechanism of the sample changer 14 is determined based on these detection signals. Be controlled.

  The radiation measuring apparatus 10 includes an operation / display unit 24 for operating the apparatus and displaying an operation screen. The operation / display unit 24 can be configured by a so-called touch panel display. In addition, the operation unit and the display unit can be separated. In this case, the operation unit can be composed of one or both of a pointing device such as a mouse and a keyboard, and the display unit can be a liquid crystal display device.

  The radiation measurement apparatus 10 further includes a power supply unit 26 that supplies power to each operation unit included in the apparatus. The operation unit includes a measurement unit 12, a sample changer 14, a central processing unit 16 as a control unit, and a PLC 18. The power supply unit 26 includes a first DC power supply 30 and a second DC power supply 32 that convert AC power of the commercial power supply 28 into DC power having a predetermined voltage. The first DC power supply 30 supplies DC power of, for example, 24V and 5V to the measurement unit 12. The first DC power supply 30 also supplies DC power of, for example, 24V and 5V to the sample changer 14 via the IF board 22. The second DC power supply 32 supplies DC power to the central processing unit 16, the operation / display unit 24 and the PLC 18 via the IF board 22. The power supplied to the central processing unit 16 and the PLC is 24V, and the operation / display unit 24 is supplied with 5V power through the step-down device 34 mounted on the IF board 22. The power supply unit 26 includes a battery 36 as an auxiliary power supply. When the power supply from the commercial power supply 28 is interrupted, the second DC power supply 32 switches the power supply source to the battery 36 and supplies the power.

  A relay 38 is provided on a path for supplying power from the second DC power supply 32 to the central processing unit 16. In the radiation measuring apparatus 10, the relay 38 is mounted on the IF board 22. The relay 38 is normally turned on, but when power is restored during the shutdown process due to a power failure of the central processing unit 16, the relay 38 is temporarily turned off and later turned on. As a result, the central processing unit 16 is activated.

  FIG. 2 shows the relationship between the power supply during a power failure and the shutdown process of the central processing unit 16. When a power failure occurs at time t1, the power supply source is switched from the commercial power source 28 to the battery 36. When a power failure is detected, the central processing unit 16 starts a shutdown process of the operation software (OS). When the shutdown process is completed at time t2, the supply of power from the battery 36 is stopped. If power is restored after the shutdown process is completed, the power supplied to the central processing unit 16 rises from the off state to the on state by power restoration, and the central processing unit 16 restarts upon detecting this rise. However, if power is restored at time t3 before the shutdown process is completed, the power supplied to the central processing unit 16 does not break as shown in FIG. In this case, since the central processing unit 16 cannot detect the rising of the supplied power, it cannot be restarted despite the power recovery. Therefore, in the radiation measuring apparatus 10, the relay 38 is turned off and on after the shutdown process is completed. With the relay 38 turned off and on, power supply to the central processing unit 16 is temporarily interrupted in the shaded area shown in FIG. This interruption creates a power rising state, whereby the central processing unit 16 is restarted. The interruption of the supply power by the relay 38 can be performed immediately after the shutdown process is completed, but may be performed after a predetermined time.

  3 and 4 are flowcharts showing the control of the radiation measuring apparatus 10 during a power failure. The power supply unit 26 monitors the occurrence of a power failure of the commercial power supply 28 (100), and supplies power by the battery 36 when a power failure is detected (102). When a power failure occurs, power supply to the operation units (the measurement unit 12, the sample changer 14, etc.) to which power is supplied by the first DC power supply 30 is cut off. On the other hand, power supply to the operation units (central processing unit 16, PLC 18, etc.) to which power is supplied by the second DC power supply 32 is continued. When a power failure occurs, the power supply unit 26 transmits a power failure detection signal S1 to the PLC 18, and the PLC 18 further transmits a power failure detection signal S2 to the central processing unit 16 (104). In addition, about the power failure detection signal S1, S2 and each signal mentioned later, the flow is shown in FIG. When the central processing unit 16 receives the power failure detection signal S2, the central processing unit 16 stores in the storage unit 20 the current state of the radiation measurement apparatus 10, that is, the state of the activated application, the state of the sample changer, and the occurrence of a power failure. (106). Based on this stored information, the interrupted processing and operation are resumed after power recovery. When the current state storage processing is completed, the central processing unit 16 executes OS shutdown processing (108).

  The power supply unit 26 monitors power recovery (110), and when the shutdown process is completed (112) before power recovery, the central processing unit 16 transmits a signal S3 indicating the completion of the shutdown process to the PLC 18, and the PLC 18 When the signal S3 is received, a signal S4 for stopping the output from the battery 36 is transmitted to the power supply unit 26 (114). Upon receiving the signal S4, the power supply unit 26 stops the power supply from the battery 36 (116). Thereafter, when power is restored, the power supplied to the central processing unit 16 rises, and the central processing unit 16 detects this rise and restarts.

  In step 110, when power recovery is detected during the shutdown process, the process waits for completion of the shutdown process (118). While waiting for completion of the shutdown process, it is monitored again whether there is a power failure (120), and if a power failure is detected, the process returns to step 110. When the shutdown process is completed, the central processing unit 16 transmits a signal S3 indicating the completion of the shutdown process to the PLC 18, and the PLC 18 transmits a signal S5 and controls the relay 38 to be in an OFF state (122). After the relay 38 is turned off, it waits for a predetermined time, for example, 5 seconds to elapse (124), and a signal S6 is transmitted to control the relay 38 to an on state (126).

  It is monitored whether or not a power failure occurs again until a predetermined time elapses after the relay 38 is turned off (128). When the power supply unit 26 detects a power failure and the PLC 18 receives the power failure detection signal S1, the PLC 18 turns on the relay 38 after a predetermined time has elapsed after the relay 38 is turned off (130) (step 132). Transition. After a power failure is detected again in step 128, whether the power is restored is monitored after the relay 38 is turned off until a predetermined time elapses (134). After the predetermined time has passed since the relay 38 was turned off. (136) The process proceeds to step 126.

  In step 126, the power supplied to the central processing unit 16 rises, and the central processing unit 16 is restarted by this rise. The central processing unit 16 reads the state of the radiation measuring apparatus 10 before the interruption of operation stored in step 108 and controls each operation unit so that the processing subsequent to this state is executed. Thereby, the radiation measuring apparatus 10 is restarted.

  DESCRIPTION OF SYMBOLS 10 Radiation measuring device, 12 Measuring part, 14 Sample changer, 16 Central processing part, 18 PLC (programmable logic controller), 20 Memory | storage part, 22 IF board (interface board), 26 Power supply part, 30 1st DC power supply, 32 1st 2 DC power supply, 36 battery (auxiliary power supply), 38 relay.

Claims (2)

A radiation measurement device for measuring radiation from a sample mixed with a liquid scintillator,
A power supply unit that supplies power from the outside to each operation unit of the radiation measurement device, and supplies power from an auxiliary power source to some operation units when the power from the outside fails.
One of the operation units, including a central processing unit, performs control of other operation units of the radiation measurement apparatus, and at the time of power failure, a control unit to which power is supplied from a power supply unit for a predetermined period;
A relay that cuts off the power sent from the power supply unit to the central processing unit;
With
When a power failure occurs, the central processing unit starts the shutdown process,
If power is restored during the shutdown process, the relay turns off after a predetermined period of time after the shutdown process is complete,
The central processing unit is activated when the relay is turned on.
Radiation measurement device. The radiation measurement apparatus according to claim 1,
If the power fails again in the period when the relay is off after the shutdown is completed, the power supply by the auxiliary power supply is stopped unless power is restored during the same period.
Radiation measurement device.

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