JP2001004751A - Travelling radiation-monitoring device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reinforce radiation control by freely and easily setting a travelling route, widening a measurement control range for it, achieving avoidance operation by considering safety for an obstacle on the running route, and minimizing required facility control. SOLUTION: A travelling radiation-monitoring device 10 is provided with a running control part 16 for running along a running route in a trackless system, a safety device 18 with a plurality of types of sensors for reporting information on an obstacle and a truck position to the running control part by detecting the information, an operation/display part 20 for giving a running command to the running control part, and a radiation control-measuring device 26 with an α-ray detector 24 with an elevator 22 in an automatic traveling truck 14 with a drive part 12. An avoidance operation is made to an obstacle on the running route according to a self-judgment function based on a detection result from a safety device, and the α-ray detector 24 is lowered by the elevator 22 at a measurement point so that it approaches a floor surface, thus intermittently measuring an α-ray surface density.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method in which a vehicle travels in a trackless manner, performs an avoiding operation by an self-judgment function for an obstacle on a traveling route, and moves an α-ray detector close to a floor at a measurement point. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-sustained traveling radiation monitor device that can be lowered to intermittently measure an α-ray surface density. This technology is particularly effective in enhancing radiation control in large nuclear fuel handling facilities.

[0002]

2. Description of the Related Art In a facility that handles radioactive materials, radiation management is performed to maintain safety. Usually, a radiation administrator manually collects a sample and measures the radiation, or measures the α-ray surface density at the original position using an α-ray survey meter or the like. However, in large facilities, such radiation management tasks require significant effort. For example, the outer passage 6 of a nuclear fuel handling facility
Looking at the case of measuring 6 points for 4 cycles,
3 minutes for work preparation, 296 minutes for manual measurement, 2 for data reduction
It takes 0 minutes, a total of 376 minutes of working time (actual working time).

[0003] Therefore, use of a traveling radiation monitoring apparatus has been proposed. This is because a guiding tape is laid beforehand in the outer peripheral passage of a large facility that is a traveling route, and the traveling radiation monitoring device is guided by the guiding tape and orbits the outer peripheral passage, and detects α-rays at a predetermined measurement point. It is intended to measure the α-ray surface density with a measuring instrument.

[0004]

However, such a traveling type radiation monitoring apparatus has a drawback that the traveling range is limited and a wide range of measurement cannot be performed because the traveling method is a track type.
In addition, since an avoidance operation cannot be performed for an obstacle on a traveling route, it is difficult to deal with safety in a place where articles are placed or a place where there are many pedestrians.

[0005] Further, since the guide tape is used for the track,
Complicated equipment maintenance such as laying tapes and repair work is required, which requires a lot of cost. There is also a disadvantage that the degree of freedom of measurement is low, such as difficulty in changing the traveling route.

SUMMARY OF THE INVENTION It is an object of the present invention to set a traveling route freely and easily, thereby making it possible to widen a measurement management range, and to avoid an obstacle on the traveling route in consideration of safety, and to perform a necessary operation. An object of the present invention is to provide a traveling radiation monitoring device capable of strengthening radiation management by minimizing equipment management.

[0007]

According to the present invention, there is provided a traveling control unit for causing a self-propelled bogie provided with a driving unit to travel the bogie in a trackless manner along a predetermined traveling route, an obstacle, and an obstacle. A safety device equipped with a plurality of types of sensors for detecting information on a bogie position and informing the traveling control unit of the information, an operation / display unit for giving a traveling command to the traveling control unit, and an α-ray detector with an elevator The traveling control unit performs an avoidance operation on an obstacle on a traveling route by a self-judgment function based on a detection result from the safety device, and the radiation management / measuring device performs measurement. This is a traveling radiation monitor device in which an α-ray detector is lowered at a point by an elevator so as to approach the floor surface so that the α-ray surface density can be measured intermittently.

[0008] The radiation management and measuring device includes an α-ray detector, a preamplifier thereof, an elevator for elevating and lowering the α-ray detector and the preamplifier, a measuring unit connected to the preamplifier, and a floor surface. It is preferable to include a distance sensor that measures the distance between the detector and the α-ray detector, and a computer extension unit that controls the elevator and records the measurement results.

[0009]

FIG. 1 is an explanatory view showing one embodiment of a traveling radiation monitoring apparatus according to the present invention. The traveling radiation monitoring apparatus 10 includes a drive unit 12 and a self-propelled carriage 14.
A traveling control unit 16 for traveling the bogie 14 along a predetermined traveling route in a trackless manner;
A safety device 18 having a plurality of types of sensors for notifying
An operation / display unit 20 for giving a traveling command to the traveling control unit 16 and a radiation management / measuring device 26 having an α-ray detector 24 with an elevator 22 are mounted.

The drive section 12 includes wheels mounted on the carriage 14, a rotation drive mechanism for the wheels, a variable speed mechanism, a variable travel direction mechanism, and the like, and receives electric energy supplied from a battery (rechargeable battery) 28. This is a structure in which the carriage 14 can run on its own.

The safety device 18 includes an infrared sensor 3 for detecting infrared reflection tapes provided on the front and the ceiling of the carriage 14.
0, a number of ultrasonic sensors 32 disposed on the side of the truck, various sensors for detecting and reporting information on obstacles such as a pressure sensor 34 provided on a truck bumper and the position of the truck, a contact stop switch 36, and a stop button 38. , A warning light 40 and the like. The contact stop switch 36 is a switch for automatically stopping when the cart 14 comes into contact with something, and the stop button 38 is used for forcibly stopping the traveling of the cart 14 by an operator or the like for some reason. It is. The warning light 40 is for calling a pedestrian's attention.

The operation / display unit 20 comprises a CRT, a keyboard, and the like, and is for giving various commands to the traveling control unit 16 and the like.

The traveling control unit 16 controls the carriage 14 to travel on a predetermined traveling route according to a command relating to the traveling route and traveling conditions. The traveling control unit 16
Performs an avoidance operation on an obstacle on the traveling route by a self-judgment function based on the detection result from the safety device 18.

In addition, the trolley 14 is equipped with a sound generating device 42, which can provide music and voice guidance, thereby calling attention of pedestrians.

The radiation control and measurement device 26 includes an α-ray detector 24 having a scintillator 44 and a photomultiplier tube (PMT) 46, a preamplifier (PA) 48, an elevator 22 for raising and lowering them, It comprises a measuring unit 50 connected to the amplifier 48, a distance sensor 52 for measuring the distance between the floor surface and the α-ray detector 24, and a computer expanding unit 54 for controlling the elevator 22 and recording the measurement results. I have. At the measuring point, the scintillator 44 of the α-ray detector 24 by the elevator 22
Is lowered so as to approach the floor surface, and the α-ray surface density is measured intermittently.

The α-ray detector 20 is a ZnS scintillation detector here, and is manufactured according to the following specifications. Effective area: 113 cm ² Detection limit: 2 × 10 ⁻³ Bq / cm ² or less Measurement range: 0 to 10 ⁵ cpm Counting efficiency: 10% or more

Here, a laser sensor is used as the distance sensor 52. The distance sensor 52 allows the elevator 22
Is controlled by setting the distance (maximum 20 mm) between the floor and the α-ray detector (scintillator) in units of 1 mm.

Data transmission between the traveling radiation monitor apparatus 10 and a computer system 60 installed outside is performed by F
This is performed by a D (floppy disk) 62. The traveling control input (traveling route and traveling conditions) to the traveling radiation monitoring apparatus 10 is made to the computer system 60, and it is input to F
Write to D. Using the operation / display unit (keyboard or CRT) 20 of the traveling radiation monitor device 10, the FD data is taken into the traveling control unit 16. As a result, the traveling radiation monitoring apparatus 10 is in a state in which it can travel on the determined traveling route and traveling conditions. Therefore, if the travel control input to the travel type radiation monitoring apparatus 10 is reset, traveling at an arbitrary place becomes possible. In addition, the operation / display unit 20 of the traveling radiation monitor device 10 can also be used to confirm the currently set traveling route and traveling conditions.

The computer system 60 is equipped with measurement analysis software, which enables input of measurement conditions and analysis and output of measurement results. The measurement conditions are written into the FD, and the measurement conditions are taken into the travel control unit 16 and the computer extension unit 54 using the operation / display unit (keyboard or CRT) 20 of the travel type radiation monitor device 10. In accordance with the measurement condition data, the travel of the traveling radiation monitor apparatus 10 stops at a predetermined measurement position, and the measurement is performed by bringing the α-ray detector 24 close to the floor surface in a predetermined procedure. The measurement result is temporarily stored in the computer extension unit 54, and then written to the FD. The FD data is taken into the computer system 60, and analysis processing is performed by measurement analysis software.

In this traveling type radiation monitor apparatus 10, the minimum size (detection limit value) that each sensor can recognize as various obstacles is the height 10 regardless of the material.
cm or more and 4.5 cm or more in width. for that reason,
It is sufficiently sensitive to equipment such as workers or equipment, and there is no problem with safety at all. When an obstacle is present on the traveling course, the ultrasonic sensor 32 recognizes the obstacle about 2 m before the obstacle, and is programmed to avoid the obstacle in a non-contact state and return to the original traveling course.

The working time required for measurement using the traveling radiation monitoring apparatus of the present embodiment is, for example, the same as that described in the above-mentioned prior art.
When measuring points for four cycles, 13 minutes for work preparation, 372 minutes for automatic measurement, and 1 minute for data reduction
Five minutes, a total of 400 minutes, of which 28 hours are the actual work time for work preparation and data reduction. Compared with the conventional manual measurement, the use of the present traveling radiation monitoring apparatus has enabled a labor saving of about 90% per work.

Next, the measurement range will be described. In the case of the orbit method (tape guidance method) (comparative example: see FIG. 2B), the self-propelled radiation monitoring device 65 can measure only in a limited range on the guidance tape 68 laid in the passage 66. However, in the case of the trackless system as in the present invention (see FIG. 2A), the self-propelled radiation monitoring apparatus 10 can arbitrarily set a traveling course, and therefore, compared to the track system. The management range 70 can be widened. For example, in FIG.
Then, 3 of center course a, left course b, right course c
The course is set for each course and measured. As a result, it is possible to manage the passage 66 almost entirely.

FIG. 3 shows an example of running course setting and bogie position detection. Here, the drawing of the passage of the building (dimensions are set in accordance with the X and Y coordinates) is input to the travel control unit in advance, and the current position of the self-propelled radiation monitor device 10 is set to the travel start position 72.
Alternatively, a method of recognizing from the stop location 74 is used. During traveling, the vehicle travels while always confirming the distance to the wall with an ultrasonic sensor. In some cases, a difference between the actual traveling distance and the stored linear distance on the drawing may occur due to turning and obstacle avoiding operations, etc., so that a position correction mark (metal tape) is provided in advance at several places on the ceiling above the traveling route. 76 is installed, and it is read by an infrared sensor to check and correct the position periodically.

The traveling radiation monitor stops at a preset stop (measurement point). Thereafter, the α-ray detector is lowered, and measurement is started at a predetermined position. In other words, during traveling, as shown in FIG. 4A, the α-ray detector 24 is held by the elevator 22 while being raised from the floor surface 80 in order to avoid obstacles on the floor surface. At the measurement point, as shown in FIG. 4B, the distance from the α-ray detector 24 to the floor surface 80 is measured by the distance sensor 52, and the elevator 22 is actuated based on the measurement result to move the α-ray to a predetermined position. The detector 24 is lowered and the α-ray surface density is measured. In the α-ray management, high detection efficiency cannot be obtained unless the distance between the α-ray detector and the object to be measured is as close as possible. Therefore, here, the distance between the α-ray detector 24 and the object to be measured (floor surface 80) is set. Is set to about 1 mm.

The measurement time is set in consideration of the work processing speed. Since it has a detection limit value of about 2 × 10 ⁻³ Bq / cm ² or less at a setting of 1 minute, the control target value (4 × 10
^-2 Bq / cm ² ) was confirmed to be sufficiently manageable. The measurement result is stored in the built-in computer extension unit 5.
In step 4, the data is stored.

In a normal measurement, as shown in FIG.
The measurement is performed with the line detector 24 approaching the floor surface 80. However, as shown in FIG. 5B, at the measurement point,
If the obstacle 82 is scattered on the floor 80,
The presence of the obstacle 82 is detected by the distance sensor 52 in a non-contact manner, and the descending amount of the α-ray detector 24 is suppressed. This prevents damage to the detector window surface (light shielding film) 24a.

Although the preferred embodiment of the present invention has been described in detail, the present invention is not limited to only such a configuration. In the above embodiment, various data are transmitted between the traveling radiation monitoring apparatus and the external computer system by the FD. However, a wireless method (including optical communication and infrared communication) and a wired method by cable connection are used. Data may be transmitted. The type and number of various sensors constituting the safety device may be appropriately changed.

[0028]

As described above, the present invention is a traveling radiation monitor configured to automatically perform radiation measurement, and it is possible to perform continuous work environment management in a facility intermittently. In addition, the radiation management can be strengthened to an ideal while significantly reducing the work of the radiation manager. In addition, radiation exposure of the radiation administrator during radiation measurement can be reduced.

In addition, the following effects can be obtained by using the traveling radioactive monitoring device according to the present invention. Since the traveling method is trackless, the traveling range is widened, the range of radiation management can be expanded, and radiation management can be strengthened. In addition, since the running method does not use an induction tape or the like at all, operations such as tape laying and repair are not required, and equipment management costs can be reduced. Since the detection limit of the traveling radioactive monitoring device can be made the same as the regular measurement by the radiation manager, the management can be performed sufficiently below the management target, and there is no problem in the measurement evaluation. For obstacles on the traveling route, various sensors and self-judgment function can take evasive action considering safety,
If the facility has a secure passage, safe driving is possible even when articles are placed or there are many pedestrians. Since the traveling route setting only needs to store the building drawing and the traveling route, operation at other facilities can be easily performed, and the applicable range can be expanded. Radiation management work in a large facility requires a great deal of labor, but labor in the α-ray surface density measurement work can be reduced by about 90% compared to manual measurement.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing one embodiment of a traveling radioactive monitor device according to the present invention.

FIG. 2 is an explanatory diagram for comparing a traveling route and a measurement range.

FIG. 3 is an explanatory diagram of a building drawing and a traveling route.

FIG. 4 is an explanatory diagram showing the position of a detector during traveling and at the time of measurement.

FIG. 5 is an explanatory diagram showing the positions of the detector at the time of normal measurement and at the time of detecting an obstacle.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Traveling radiation monitor apparatus 12 Drive part 14 cart 16 Travel control part 18 Safety device 20 Operation / display part 22 Elevator 24 Alpha ray detector 26 Radiation management measuring device

[Procedure amendment]

[Submission date] March 16, 2000 (200.3.1.1)
6)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

1. A traveling control unit for causing a self-propelled bogie having a drive unit to travel the bogie in a trackless manner along a predetermined traveling route, and detecting information on an obstacle and a bogie position. A safety device having a plurality of types of sensors for notifying the travel control unit, an operation / display unit for giving a travel command to the travel control unit, and a radiation management and measurement device for detecting α-rays , The travel control unit performs an avoidance operation on an obstacle on a travel route by a self-judgment function based on a detection result from the safety device, and the radiation management and measurement device includes an α-ray detector, a preamplifier thereof, , Those
an elevator for raising and lowering the α-ray detector and the preamplifier;
Measurement unit connected to the amplifier and the floor and the α-ray detector.
Distance sensor to measure the distance, control of the elevator and measurement
It is equipped with a computer extension that records the fruits, and the α-ray detector is lowered by the elevator at the measurement point so as to be close to the floor so that the α-ray surface density can be measured intermittently. Radiation monitor. ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 28, 2000 (2007.2
8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

Claims (2)

[Claims] 1. A traveling control unit for causing a self-propelled bogie having a drive unit to travel the bogie in a trackless manner along a predetermined traveling route, and detecting information on an obstacle and a bogie position. Equipped with a safety device equipped with a plurality of types of sensors that notify the travel control unit, an operation / display unit for giving a travel command to the travel control unit, and a radiation management / measurement device equipped with an α-ray detector with an elevator. , The travel control unit performs an avoidance operation on an obstacle on a travel route by a self-judgment function based on a detection result from the safety device, and the radiation management measurement device uses an α-ray detector by an elevator at a measurement point. A traveling radiation monitor apparatus characterized in that an α-ray surface density can be intermittently measured by lowering the α-ray surface so as to approach the floor surface. 2. A radiation management and measurement device, comprising: an α-ray detector;
The preamplifier, an elevator for elevating and lowering the α-ray detector and the preamplifier, a measurement unit connected to the preamplifier, and a distance sensor for measuring an interval between the floor surface and the α-ray detector, 2. The traveling radiation monitor according to claim 1, further comprising a computer extension unit for controlling the elevator and recording the measurement results.