JPS5842409B2 - sodium fluoroscope - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sodium fluoroscopy device for observing the upper surface of a fuel assembly nodding head by transmitting and receiving ultrasonic waves in a liquid metal such as sodium.

A sodium fluoroscopy system is a device that uses an ultrasonic transducer to scan and observe the upper surface of the fuel undling head in the sodium coolant inside a nuclear reactor. Since the sodium itself has to act as a lubricant, in devices that operate at low speed and intermittently, such as sodium fluoroscopes, frictional force becomes excessive in the sliding parts, which is highly likely to cause failure.

To explain using drawings, Fig. 1 shows the overall diagram, and Fig. 2 shows the overall diagram.
A detailed sectional view of the transducer drive mechanism 6, which is the main part in the figure, is shown.

Conventionally, in FIG. 2, in order to perform spiral scanning, the transducer 10 rotates the bevel gear 8 and simultaneously rotates the guide plate 7. There is a possibility that the frictional force between the female thread and the male thread of the threaded rod 9 will become large, resulting in a failure of the entire sodium fluoroscopy device.

Furthermore, since the threaded rod 9 is moved back and forth each time scanning is performed, it is necessary to rotate the bevel gear 8 in forward and reverse directions, and it is necessary to provide a mechanism to prevent the threaded rod 9 from overshooting, which is inconvenient.

The present invention has been made in view of the above-mentioned circumstances, and by using a cam in the sliding part of the drive mechanism of the sodium fluoroscope, it is possible to reduce malfunctions of the sodium fluoroscope due to increased friction, and also to reduce the possibility of failure of the sodium fluoroscope due to increased friction. The object of the present invention is to obtain a sodium fluoroscope capable of continuous spiral scanning without intermittent rotation operations.

An embodiment of the present invention will be described below with reference to the drawings.

On the other hand, parts having the same functional structure as the conventional one are given the same reference numerals, and detailed description thereof will be omitted.

In FIG. 1, the sodium fluoroscope has a driving source 3 on a rotating plug 1, and reaches through the rotating plug 1 to the vicinity of the upper surface 2 of the handling head of the fuel assembly below the sodium liquid level.

A pantograph mechanism 4 is provided below the sodium liquid level, a transducer drive mechanism 6 is attached to it, and the drive source 3 and the transducer drive mechanism 6 are connected by a drive transmission shaft 5.

FIG. 3 shows a detailed view of the transducer drive mechanism 6 of the present invention.

The drive transmission shaft 5 is connected to the heart-shaped cam 11 and the guide plate 7 via gears (not shown) so that the driving forces can be separated.

Attached to the guide plate 7 is a liner 13 having rollers 12 and surrounding a support rod 14 to which the transducer 10 is attached.

The heart-shaped cam 11 and the roller 12 for reducing friction are brought into close contact by a spring 15.

The heart-shaped cam 11 is for reciprocating the liner 13 at a constant speed, and the liner 13 is guided to move linearly.

The support rods 14 are connected by a universal joint 16 to smoothly absorb displacement of the transducer 10.

Next, the operation of the above device will be described.

First, the pantograph mechanism 4 of the sodium fluoroscope is opened using the drive source 3, and the transducer drive mechanism 6 is positioned above the upper surface of the handling head of the fuel assembly.

Next, when the drive source 3 rotates the drive transmission shaft 5 in the above-mentioned one direction, the heart-shaped cam 11 rotates and the roller 1
The liner 13 reciprocates at a constant speed via the guide plate 2, and the guide plate 7 rotates, causing the liner 13 mounted on the guide plate T to rotate.

Accordingly, the liner 13 spirally moves with a simultaneous combination of reciprocating motion and rotational motion, allowing the transducer 10 to perform spiral scanning.

As explained above, according to the sodium fluoroscopy device of the present invention, a cam is used in the transducer drive mechanism of the sodium fluoroscopy device to prevent failures caused by increased frictional force in the sliding parts, thereby preventing failure of the entire sodium fluoroscopy device. can be reduced.

In addition, the present invention has the following effects.

(1) There is no need for a stopper to prevent the threaded rod from overshooting, resulting in space savings.

(il) Since the cam is used, the operation can be performed continuously,
There is no need for a function to reverse each scan, which simplifies the operation sequence and reduces malfunctions and failures.

[Brief explanation of drawings]

FIG. 1 is an overall view of a sodium fluoroscope, FIG. 2 is a schematic vertical cross-sectional view of a conventional transducer drive mechanism, FIG. 3 is a schematic vertical cross-sectional view showing an embodiment of the transducer drive mechanism of the present invention, and FIG. The figure is a cross-sectional view of FIG. 3 taken along lines 1 to 2 and viewed in the direction of the arrows. 3... Drive source, 10... Transducer, 11... Heart-shaped cam, 12...
·roller.

Claims (1)

[Claims] 1. In a sodium fluoroscopy device that observes liquid metal by spirally moving an ultrasonic transducer in liquid metal,
A sodium fluoroscope characterized in that the spiral motion of the ultrasonic transducer is achieved by reciprocating the transducer with a cam and rotating the transducer and the cam.