JPS6122882B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sodium fluoroscopy system, and particularly to a type that uses a fuel exchanger hold down arm to observe the top of a fuel assembly. This sodium fluoroscopy device has a mechanism for adjusting the inclination and forward and backward stroke operations.

The interior of fast breeder reactors, especially those that use liquid metal as a coolant, cannot be directly observed with the naked eye. For this reason, in fast breeder reactors, a transducer that transmits and receives ultrasonic waves is moved above the fuel assembly, and a sodium fluoroscope is used to observe the top of each fuel assembly to check for abnormalities. Due to manufacturing and installation errors in the shielding plug, fuel exchanger hold town arm, etc., the sodium fluoroscopic device installed in the hold town arm of the single-rotation fixed arm type fuel exchanger was placed against the top of the fuel assembly. Causes a tilt. In addition to this, the top of the fuel assembly also tilts due to swelling and the like. These inclinations exceed the allowable relative inclination between the ultrasonic transmitting surface of the transducer and the top of the fuel assembly, making it impossible to catch reflected waves and making observation impossible. In particular, in sodium fluoroscopy equipment, the beam is narrowed down to increase resolution, so if the tilt exceeds the allowable tilt amount, it is necessary to adjust the tilt to an appropriate tilt.

Conventional sodium fluoroscopy equipment uses a transducer.
Since the structure uses the scanning guide directly as a guide for the longitudinal stroke movement of the transducer holder, in order to adjust the inclination of the transducer, it is necessary to either tilt the entire scanning guide or directly tilt the transducer holder. Although there is a method, it is difficult to implement because it has the following drawbacks. In the former case, the scanning guide is an element of the collapsing mechanism when inserted into and withdrawn from the furnace, and is rigidly connected to the sodium fluoroscope body and collapsing arm with pin bearings to prevent sideways movement. Therefore, it is extremely difficult to create a flexible structure that allows for tilting and rotational movement. In the latter case, when the transducer holder moves back and forth, the tilt adjustment mechanism also needs to move at the same time. is complicated, and driving it in sodium can cause failures and is not desirable in terms of reliability.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sodium fluoroscope having a transducer tilt adjustment mechanism which eliminates the above-mentioned drawbacks and which does not cause problems due to the back and forth stroke movement of the transducer holder and the folding and folding movement of the arms. It's about getting the equipment.

Hereinafter, the present invention will be explained in detail using the drawings of one embodiment. FIG. 1 is an overall schematic view of the present sodium fluoroscope, and FIG. 2 is an enlarged view of the collapsing mechanism, the longitudinal stroke movement mechanism, and the tilt adjustment mechanism. FIG. 3 is a detailed view of the tilt adjustment mechanism section. As shown in the figure, the drive unit 10 of the fluoroscopy device is provided on the shield plug 2. Furthermore, inside the scanning guide 11 of the folding mechanism consisting of the scanning guide 11, the folding arm 12, the pulling shaft 13, and the rotating housing 14, a transducer holder guide 15 is installed to enable rotational neck vibration operation. It is attached via a pin bearing 21. There is a transducer inside the transducer retainer guide 15 so that it can move back and forth.
A retainer 16 is held on an L-shaped rail via rollers 22. On the other hand, inside the rotating housing 14, a transducer retainer guide 1 is provided.
A vertical link 17 for adjusting the inclination of 5 is housed. This vertical link 17 is connected to the horizontal link 23 by a connecting bearing 30. This horizontal link 23 is connected to the transducer retainer guide 15 by a link at the pin bearing 20 portion, and by moving the vertical link 17 along the rotary housing 14 up and down, , rotate about the pin fulcrum 18 as a fulcrum. The pin fulcrum 18 is located closer to the pin bearing 20 than the center of the horizontal link 23, and is connected to the transducer holder guide 15 by a link. Further, the connecting bearing 30 at the node between the horizontal part and the vertical part of the operation link is provided at the folding center of the scanning guide 11. The nodes on the side of the transducer retainer guide 15 are provided in the same direction as the tilt center pin bearing 21 of the transducer retainer guide 15. The transducer 19 is
It is attached to the lower surface of the retainer 16.

Next, the operation will be explained. To adjust the tilt angle of the transducer 19, first push and pull the vertical link 17 in the rotary housing 14 of the tilt operation link mechanism in the vertical direction, the horizontal link 23 rotates about the pin fulcrum 18, and the link Move the tip up and down. That is, when the vertical link 17 is pushed downward, the horizontal link 23 rotates about the pin fulcrum 18, so the pin bearing 20 moves upward.
This tip is further connected to the transducer holder guide 15 by a link, so that the transducer holder guide 15 swings and rotates about the tilt center pin bearing 21. When the transducer holder guide 15 tilts, the transducer holder 16 held inside it also tilts, and the transducer 19 attached inside it also tilts.
It will also tilt. Thus, by operating the tilt operation linkage 17, the transducer 19
The tilt can be adjusted. In addition, tilt operation horizontal link 2
Since the pin fulcrum 18, which is the operating fulcrum of No. 3, is provided closer to the pin bearing 20 than the center of the horizontal link 23, the operation of the operating section can be reduced and transmitted to the transducer retainer guide 15. You can make fine adjustments. When performing back-and-forth stroke motion of the transducer retainer 16,
The transducer cage 16 is the transducer cage guide 1.
Since it moves independently within 5 without being constrained, it does not have any adverse effect on the tilt adjustment mechanism. Also, a-
When the folding operation is performed, no problem occurs because the center of the connecting bearing 30 of the horizontal and vertical link connecting portions of the inclination adjustment mechanism is the same as the center of folding of the scanning guide 11.

In the present invention, the vertical link 17 is pushed and pulled, but as shown in FIG. 4, when pushing the vertical link 17, a spring 31 is used to reduce the pressing force to prevent the vertical link 17 from buckling. It also applies if Although Fig. 4 shows a leaf spring, a compression spring,
The same applies to the case where a bell spring is used. Further, the use of a torsion coil spring for the center pin bearing 21 is also similar.

As described above, the sodium fluoroscopy apparatus of the present invention can provide a sodium fluoroscopy apparatus having a transducer tilt adjustment mechanism that does not interfere with the forward/backward stroke operation and the unfolding/folding operation. This ensures that even if the relative inclination between the transducer and the top of the fuel assembly exceeds a permissible value due to inclination due to reactor structure fabrication, installation tolerances, and inclination due to swelling of the fuel assembly, the inclination of the transducer Observations can be made by adjusting the By being able to adjust the inclination, it is possible to reduce the precision required for manufacturing and installing the sodium fluoroscope mechanism, and the transducer can be accurately directed to the surface to be observed, thereby improving precision. Furthermore, the tilt adjustment mechanism of this sodium fluoroscope uses parts that have been used frequently in sodium, and uses a simple operating principle, so it is a mechanism that is less likely to fail.

[Brief explanation of the drawing]

FIG. 1 is an overall schematic diagram showing an embodiment of the sodium fluoroscopy device of the present invention, FIG. 2 is an explanatory diagram of the inclination adjustment mechanism shown in FIG. 1, and FIGS. 3 and 4 are partial details of FIG. 2. FIG. 3 is a front view, and FIG. 4 is a side view. 11...Scanning guide, 14...Rotating housing, 15...Transducer retainer guide, 1
7... Vertical link, 18... Pin fulcrum, 19...
Transducer, 21...Pin bearing, 23...
Horizontal link, 30...Connection bearing, 31...Spring.

Claims (1)

[Claims] 1. A housing installed vertically so as to be freely rotatable in the horizontal direction, a scanning guide provided at the bottom of the housing so as to be freely foldable around the mounting shaft, and a scanning guide that is driven vertically along the axial direction of the housing. A folding arm connects the lower part of the pulling shaft to a part spaced a predetermined distance from the mounting shaft of the scanning guide, and a folding arm connects the lower part of the pulling shaft to a part spaced a predetermined distance from the mounting shaft of the scanning guide. A cage guide is provided to be rotatable relative to the guide, a horizontal link is provided to be rotatable around a pin fulcrum fixed to the scanning guide, and a housing is connected to one end of the horizontal link via a bearing. a vertical link installed along the horizontal link, a mechanism connecting the other end of the horizontal link to a point spaced apart from the pivot axis of the retainer guide, and a mechanism installed above the housing to connect the lifting axis and the vertical link. 1. A sodium fluoroscopic device comprising a driving part and a plurality of transducers attached to the lower surface of a cage guide, the mounting shaft part and a connecting bearing being set at the same position.