JPH089677Y2 - Self-guided mechanism for reactor core components - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a self-guiding mechanism for a reactor core component.

(Prior Art) The core of a fast breeder reactor is constructed by arranging hundreds of core constituent elements having a regular hexagonal cross section in a close equilateral triangular lattice. When one core component is pulled out in order to replace the core component from this core, a hexagonal hole is created there. When a new core component is to be inserted into this hexagonal hole, each side of the hexagonal hole does not match each side of the new core component (6) as shown in Fig. 4 (new If the core component (6) is deviated by an angle θ with respect to the hexagonal hole), each side of the new core component (6) interferes with the core component (7) around the hexagonal hole, and the new core configuration The element (6) cannot be inserted into the hexagonal hole and the new core component (6) must be rotated by an angle θ.

FIGS. 5 (I) and (II) show a conventional example of a core component self-guiding mechanism in which a new core component is rotated by an angle θ by the core component around a hexagonal hole. 5 (I), (2) is the upper end of the core component, (4) is the arcuate shaving slide surface provided at the upper end (2), and (3) of FIG. 5 (II) is the core. The entrance nozzle roots (lower part) and (5) of the constituent elements are oblique square-shaped shaving key parts provided in the entrance nozzle root part (3). As shown in FIG. 6, the new core constituent element (6) A square-shaped shaving key part (5) provided on the root part (3) of the entrance nozzle is engaged with an arc-shaped shaving sliding surface (4) provided on the upper end of the core component (7) around the hexagonal hole. After joining, the new core component (6) is lowered, and the oblique square shaving key part (5) is moved along the arc-shaped shaving slide surface (4) to move the new core component (6). The new core component (6) is rotated after it is rotated by an angle θ to match the new core component (6) with the hexagonal hole. It is designed to be inserted into a hexagonal hole.

(Problems to be solved by the invention) In the conventional self-guided mechanism rotating mechanism for core components shown in Figs. 5 and 6, in order to reliably rotate the new core component (6), arc cutting The sliding surface (4) is required to have a complicated geometry and high accuracy. In addition to that, it is difficult to machine the arcuate cutting sliding surface (4) and the oblique square cutting key portion (5), and moreover, there is a problem that a dimensional inspection or the like is required and the cost becomes high.

The present invention is proposed in view of the above problems, and an object of the present invention is to provide a self-guiding mechanism for a reactor core component that can reduce manufacturing costs.

(Means for Solving the Problems) In order to achieve the above object, the self-guiding mechanism of the reactor core component of the present invention has, for example, a north pole on each upper surface of the hexagonal cross section of the core component. Then, the magnet plates are fixed with the S poles facing down, and the N poles are fixed on the respective surfaces of the root of the entrance nozzle having a hexagonal cross section at the bottom of the core component, and the magnet plates are fixed with the S poles facing down. In this way, magnet plates are attached to the upper surface of the hexagonal cross section of the core component and the surfaces of the entrance nozzle root of the hexagonal cross section of the lower part of the core component, respectively, in the axial direction of the core component. They are aligned and fixed.

(Operation) The self-guiding mechanism of the reactor core component of the present invention is configured as described above, and when the new core component is to be inserted into the hexagonal hole, the core component around the hexagonal hole The north pole of the magnet plate attached to the upper end and the south pole of the magnet plate attached to the root of the entrance nozzle of the new core component attract each other, and the new core component is rotated in the direction to match the hexagonal hole, Allows insertion of new core components into hexagonal holes.

(Example) Next, the self-guided mechanism of the reactor core components of the present invention
Explaining with reference to the embodiment shown in FIGS. 1 and 2, (2) in FIG. 1 (I) is arranged on each upper surface of the hexagonal cross section of the core component, and (1a) is arranged on each surface of the upper end (2). Multiple magnet plates,
(8) is a screw for fixing each magnet plate (1a) to the same upper end portion (2), (3) in Fig. 1 (II) is a root portion of a hexagonal cross section of the core component lower part, (1b) ) Is a plurality of magnet plates arranged on each surface of the entrance nozzle root (3), and (8) is a screw for fixing each magnet plate (1b) to the entrance nozzle root (3), the second In Fig. 3, (6) is the new core component to be newly inserted, and (7) is the core component around the hexagonal hole.

Next, the operation of the self-guiding mechanism for the reactor core components shown in FIGS. 1 and 2 will be specifically described. When the new core component (6) is to be inserted into the hexagonal hole, the magnet plate (1a) attached to the upper end (2) of the core component (7) around the hexagonal hole as shown in FIG. ) And the north pole of the magnet plate (1b) attached to the entrance nozzle root (3) of the new core component (6) attract each other, and the new core component (6) is aligned with the hexagonal hole. Rotation in the direction to allow insertion of the new core component (6) into the hexagonal hole.

Fig. 3 shows that the magnet plate (1a) is attached by displacing it from the center of the upper end (2) of the core component to one side.
The root of the entrance nozzle at the bottom of the core component (3)
Another embodiment is shown, which is attached by shifting from one side to the other side from the center. In this embodiment, the magnetically balanced points deviate from the geometrically balanced points. Therefore, if some external force, for example, a pushing force is applied to the new core component (6), even if the new core component (6) is magnetically balanced at the time of insertion. Can be inserted.

(Effect of the Invention) As described above, the self-guiding mechanism of the reactor core component of the present invention is installed at the upper end of the core component around the hexagonal hole when the new core component is inserted into the hexagonal hole. The N pole of the attached magnet plate and the S pole of the magnet plate attached to the entrance nozzle root of the new core component attract each other, and the new core component is rotated in a direction to match the hexagonal hole,
Since the new core components can be inserted into the hexagonal holes,
It is possible to reduce the manufacturing cost of the self-guiding mechanism without the need for machining, dimensional inspection, etc. of the arcuate cutting sliding surface and the arcuate cutting sliding surface that require complicated geometric shapes and high accuracy. effective.

[Brief description of drawings]

FIG. 1 (I) is a perspective view showing one embodiment of the upper end side of the self-guiding mechanism of the reactor core component according to the present invention, and FIG. 1 (II) is a perspective view showing one embodiment of the lower side thereof. Fig. 2, Fig. 2 is a diagram for explaining the action, Fig. 3 is a diagram for explaining the action of another embodiment, and Fig. 4 is a diagram for explaining problems during insertion of new core components,
FIG. 5 (I) is a perspective view showing the upper end side of the conventional self-guiding mechanism of the reactor core component, FIG. 5 (II) is a perspective view showing the lower side thereof, and FIG. Is. (1a) (1b) …… Magnet plate, (2) …… Upper end of reactor core components, (3) …… Root part of entrance nozzle below core components.

Claims (1)

[Scope of utility model registration request] 1. A hexagonal entrance nozzle with a hexagonal cross section at the bottom of the core component, wherein, for example, the N pole is on the upper side and the S pole is on the lower side on each surface of the upper end portion of the hexagonal cross section of the core component. The hexagonal cross section of the upper end of each core component and the hexagonal cross section of the core component are fixed by fixing the magnet plate with the N pole on each face of the root and the S pole on the bottom. A self-guiding mechanism for a reactor core component, wherein magnet plates are fixed on each surface of the nozzle root portion so as to have polarities aligned with the axial direction of the core component.