JPH078788U - Surface contamination wiper - Google Patents

Abstract

(57) [Summary] [Constitution] The surface contamination wiping device of the present invention is a suction pump 1.
The hose 10 sucked at 1 is connected to the push rod 7 of the head 4 to make the space between the cap 2 with the filter paper 1 and the concave portion of the head 4 a negative pressure, and the pressure detector 12 provided on the hose 10
When the generation of the gap between the cap 2 and the magnet 3 is detected by the above, the pressing force is reduced by returning the mounting base 6 to return the gap to zero, and the optimum pressing force is applied when the gap is zero. The position of the mounting base 6 is controlled by the control unit 13 via the mounting base drive mechanism 14 so that the negative pressure is obtained by the pressure detector 12. [Effect] The cap 2 with filter paper can be prevented from falling off, and an optimum pressing force can be applied to the filter paper 1. Thereby, accurate wiping can be performed. Further, since the work such as the collection and the attachment of the cap with the filter paper, which have occurred due to the falling off, is eliminated, it is possible to reduce the radiation exposure of the worker.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an apparatus for wiping the surface of a cylindrical container such as a drum can containing radioactive waste in order to inspect the surface for contamination.

[0002]

[Prior art]

 Wastes generated from radioactive material handling facilities such as nuclear power plants and reprocessing facilities are solidified and stored in cylindrical containers such as drums.

The surface contamination must be measured in terms of management at this time, and the method of wiping the surface of the container with filter paper and measuring the attached radioactive substance with a radiation detector is called the smear method.

FIG. 2 shows a conventional wiping device. In FIG. 2, the filter paper 1 is attached to the cap 2 with an adhesive or the like. The cap 2 is held by the magnetic force of a ring-shaped magnet 3 attached to the concave portion of the head 4. Wiping is performed by a drive mechanism that changes the position of the mounting base 6 and a mechanism that rotates the cylindrical container 8. The pressing force of the filter paper 1 is generated by the distance between the mounting base 6 and the cylindrical container 8 and the bending of the spring 5, and the spring 5 expands and contracts according to the concave and convex of the wiping surface. The push rod 7 is fitted into the support shaft of the head 4 and extends to the tip surface thereof, and is pushed when the cap 2 is detached from the head 4 to separate the cap 2 from the magnet 3.

[0005]

[Problems to be solved by the device]

 In the above-described conventional wiping device, since the distance between the mounting base 6 and the cylindrical container 8 is constant, if the surface of the container has a protrusion more than expected, the spring 5 is deformed in the compression direction. The increase in the flexure of the) increased, and an excessive pressing force was generated. This excessive pressing force increases the frictional force of the wiping surface of the filter paper 1, so that the cap 2 with the filter paper 1 has a drawback of coming off from the magnet 3 of the head 4.

Therefore, an object of the present invention is to provide a surface-contamination wiping device that can prevent the cap with filter paper from falling off.

[0007]

[Means for Solving the Problems]

 The surface contamination wiping device of the present invention connects a hose sucked by a suction pump to the outer end of a push rod having a central through hole to make a negative pressure in the space between the cap and the head, and When the pressure detector provided detects the occurrence of a gap between the cap and magnet, the mounting base is retracted to reduce the pressing force to return it to zero, and the optimum pressing force is applied when the gap is zero. It is characterized in that the position of the mount is controlled by the controller via the mount drive mechanism so that the negative pressure in the state can be obtained by the pressure detector.

[0008]

[Action]

 In the surface contamination wiping device of the present invention, when the cap with the filter paper is about to come off, a gap is created between the cap and the magnet, and air is introduced from this gap to increase the pressure. The rising pressure is detected by the pressure detector and transmitted to the control unit. The control unit determines that a gap has occurred, and sends a signal for retracting the mount to the mount drive mechanism, and the drive mechanism retracts the mount to reduce the pressing force. As a result, the excessive rubbing force acting on the filter paper disappears, and the cap comes into close contact with the magnet due to the magnetic force of the magnet to eliminate the gap. As a result, the inflow of air stops and the pressure drops. With this pressure drop, the control unit judges that the clearance is zero and sends a forward signal to the mounting base drive mechanism to move the mounting base forward. Next, if the detected pressure sent from the pressure detector returns to the reference pressure when the gap between the cap and magnet is zero, the control unit determines that the optimum pressing force is being applied, and sends a movement stop signal to the mounting base. Send to the drive mechanism and stop the mount.

[0009]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings.

FIG. 1 shows a surface contamination wiping device according to an embodiment of the present invention. In FIG. 1, the filter paper 1 is attached to the cap 2 with an adhesive or the like. The cap 2 is held by the magnetic force of a ring-shaped magnet 3 attached to the concave portion of the head 4. The support shaft of the head 4 is slidably held by the mounting base 6, and a pressing force corresponding to the bending of the spring 5 interposed between the concave portion of the head and the mounting base 6 is applied.

The mounting base 6 can be moved forward and backward in the axial direction of the support shaft of the head 4 by the mounting base drive mechanism 14. A push rod 7 is fitted in the center through hole of the support shaft of the head 4 and extends to the tip surface thereof. When the cap 2 is detached from the head 4, the push rod 7 is pushed to separate the cap 2 from the magnet 3. . The push rod 7 has a through hole 7a at its center.

The hose 10 sucked by the suction pump 11 is connected to the through hole 7 a at the outer end of the push rod 7 via the joint 9, and the space between the cap 2 and the concave portion of the head 4 is closed. Keep a negative pressure in the space. The hose 10 is provided with a pressure detector 12, and the detected pressure signal is sent to the controller 13.

The control unit 13 uses the detection pressure (negative pressure) of the pressure detector 12 when the cap 2 and the magnet 3 are adsorbed with a zero gap and an optimum pressing force is applied as a reference pressure. If the excessive pressing force is generated, a gap is created between the cap 2 and the magnet 3, air flows in, and the pressure rises. The control unit 13 that receives the pressure detected by the pressure detector 12 at this time is Based on the comparison with the reference pressure, it is determined that a gap has occurred, and a mount back signal is sent to the mount drive mechanism 14.

When the mounting base driving mechanism 14 retracts the mounting base 6 to reduce the pressing force, the excessive frictional force acting on the filter paper 1 disappears, and the cap 2 comes into close contact with the magnet 3 due to the magnetic force, so that there is no space. As a result, the inflow of air is stopped and the pressure drops. Upon receiving this change in pressure from the pressure detector 12, the control unit 13 determines that the normal state with zero clearance has been restored, and sends a mount advance signal to the mount drive mechanism 14 to move the mount forward, When the detected pressure sent from the detector 12 returns to the stored reference pressure, a movement stop signal is sent to the mounting base drive mechanism 14 to stop the mounting base 6.

In the surface contamination wiping device of the embodiment of the present invention configured as described above, the filter paper 1 is pressed against the rotating cylindrical container 8 with the optimum pressing force, and the filter paper 1 is attached. In a normal state, the cap 2 present is adsorbed and held by the magnet 3 of the head 4 without a gap. In a normal state, the pressure detected by the pressure detector 12 indicates a predetermined reference pressure.

Now, when the cylindrical container 8 rides on the protrusion, an excessive pressing force is generated, and a gap is generated between the cap 2 and the magnet 3 due to a rapid increase in the frictional force of the wiping surface of the filter paper 1. Air flows in through the gap to increase the pressure in the space between the cap 2 and the concave portion of the head 4. The rising pressure is detected by the pressure detector 12, and this pressure signal is sent to the control unit 13.

The control unit 13 determines from the comparison with the reference pressure that a gap has occurred, and sends a mounting base retreat signal to the mounting base drive mechanism 14. When the mounting base drive mechanism 14 retracts the mounting base 6 to reduce the pressing force, the excessive frictional force acting on the filter paper 1 disappears, and the cap 2 comes into close contact with the magnet 3 due to the magnetic force to eliminate the gap. As a result, the inflow of air stops and the pressure drops.

Upon receiving the change in pressure from the pressure detector 12, the control unit 13 determines that the normal state with zero clearance has been restored, and sends a mount advance signal to the mount drive mechanism 14. As the mounting base 6 is moved forward by the mounting base drive mechanism 14, the pressing force increases, and the contact between the cap 2 and the magnet 3 becomes closer, so that the air leak decreases and the pressure lowers and returns to the reference pressure. The control unit 13 knows that the pressure signal sent from the pressure detector 12 has returned to the reference pressure and the optimum pressing force is applied, and sends a movement stop signal to the mounting base drive mechanism 14, Stop the mounting base 6. With this, the filter paper 1 can continue to wipe the surface of the cylindrical container 8 with an optimum pressing force.

According to the surface contamination wiping device of the embodiment of the present invention, it is possible to prevent the cap with filter paper from coming off and to apply an optimum pressing force to the filter paper. As a result, accurate wiping can be performed. In addition, by eliminating the work such as the collection and the attachment of the cap with filter paper, which had occurred due to falling off, it is possible to reduce the radiation exposure of workers.

[0020]

[Effect of device]

 As described above in detail, according to the present invention, the hose sucked by the suction pump is connected to the push rod of the head to make the space between the cap with the filter paper and the concave portion of the head negative, and When the pressure detector installed on the hose detects the occurrence of the gap between the cap and magnet, the mounting base is retracted to reduce the pressing force and return the gap to zero. By realizing the surface contamination wiping device, the control unit controls the position of the mounting base via the mounting base drive mechanism so that the negative pressure under the applied pressure can be obtained by the pressure detector. , The cap with filter paper can be prevented from falling off, and the optimum pressing force can be applied to the filter paper. As a result, accurate wiping can be performed. In addition, by eliminating the work such as the collection and the attachment of the filter paper cap that were caused by the falling, it is possible to reduce the radiation exposure of workers.

[Brief description of drawings]

FIG. 1 is a schematic view showing a configuration of a surface contamination wiping device according to an embodiment of the present invention.

FIG. 2 is a schematic view showing a configuration of a conventional surface contamination wiping device.

[Explanation of symbols]

 1 ... Filter paper 2 ... Cap 3 ... Magnet 4 ... Head 5 ... Spring 6 ... Mounting base 7 ... Push rod 8 ... Cylindrical container 10 ... Hose 11 ... Suction pump 12 ... Pressure detector 13 ... Control part 14 ... Mounting base drive mechanism

Claims (1)

[Scope of utility model registration request] 1. A head in which a support shaft is slidably held by a mounting base and a ring-shaped magnet is attached in a recessed portion at the tip of the support shaft, and the recessed portion of the head and the mounting base. A spring interposed between the head and a pressing force corresponding to the flexure, a dish-shaped cap whose back surface is attracted and held by a magnet of the head, a filter paper attached to the front surface of the cap, and the head. A push rod having a center through hole slidably fitted in the center through hole of the support shaft of the above, and rotating a cylindrical container containing radioactive waste to press the filter paper against the container surface to remove surface contamination. In the device for wiping with, a mounting base drive mechanism for advancing / retracting the mounting base in the axial direction of the support shaft of the head, one end connected to the suction pump, and the other end connected to the outer end of the push rod of the head. Connected to this hose The pressure detector that is installed to detect the negative pressure in the hose, and the reference pressure that is set in advance by receiving the pressure signal detected by this pressure detector, that is, the gap between the cap and the magnet is zero, and the optimum pressing force. When the detected pressure is higher than the reference pressure in comparison with the negative pressure, it is judged that the clearance has occurred and a mounting base retreat signal is sent to the mounting base drive mechanism to retract the mounting base, and then When it is determined that the clearance has returned to zero because the detected pressure has changed to a state where the detected pressure has dropped, and a mount advance signal is sent to the mount drive mechanism to advance the mount, and the detected pressure returns to the reference pressure. A surface contamination wiping device, comprising: a control unit that determines that an optimum pressing force is applied and sends a stop signal to a mounting base drive mechanism to stop the mounting base.