JPS5924136Y2 - Terminal block for electrical wiring - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a terminal block for electrical wiring such as a valve driving device installed in a nuclear power plant containment vessel.

Terminal blocks for electrical wiring used in the containment vessels of boiling water or pressurized wooden nuclear power plants must be operated under harsh conditions such as during a coolant spill accident, for example, at a temperature of 171°C and a steam pressure of 4.5°C.
1 kg/Cm2, humidity 100% condition hinge;
It is required to maintain a withstand voltage (for example, A, C, 440V).

However, with conventional terminal blocks, steam condenses on the surface of the terminal block due to sudden temperature changes such as during a coolant spill accident.
There was a risk of electrical leakage due to water that aggregated and stagnated.

The present invention increases the creepage distance between the current-carrying parts by forming protrusions and through-holes between the current-carrying parts, and allows water condensed on the surface to flow down through the through-holes. The purpose of this invention is to provide a terminal block for electrical wiring that eliminates the risk of electrical leakage in the event of a coolant spill accident as described above. .

Reference numeral 1 denotes a stand made of an insulating material that is approximately in the shape of a rectangular parallelepiped, and its upper surface is provided with three grooves 2 extending in the front-rear direction. A protrusion 4 extending in the front-rear direction is formed on each side.

At the center of both ends of the base 1, a vertically stepped hole 5 is formed which is U-shaped in plan and opens toward the side.

This stepped hole 5 is formed by vertically connecting a large portion and a small portion that are similar in shape to each other, and by locking the head of a bolt (not shown) to the stepped portion, the base 1 may be stuck inside the terminal box (not shown).

At the locations on the lower surface of the table 1 that are aligned with each of the grooves 2,
Concave grooves 6 extending in the front-back direction are cut, and these concave grooves 6
Three concave grooves 7 are cut in the left-right direction so as to be perpendicular to the left-right direction.

Note that the width of the groove 6 is slightly narrower than the width of the joint 2, and
Among the grooves 7 in the left and right direction, the width of the center groove is slightly wider than the width of the other grooves.

Reference numeral 8 denotes a terminal receiver made of a conductive material and having a rectangular planar shape, and a projecting edge 8a facing in the left-right direction is formed at the upper end of the terminal receiver.

The terminal receiver 8 is fitted into the center of the bottom of each groove 2, and its projecting edge 8a is in contact with the bottom surface of the groove 2.

A set screw 9 is screwed onto the front and rear portions of the upper surface of the terminal receiver 8.
These setscrews 9 allow each terminal (not shown) of electrical wiring to be connected to each other to be fixed to the terminal receiver 8.

Between each terminal receiver 8 and each protrusion 4 on the base 1, and between the left and right terminal receivers 8 and each protrusion 3, there are vertical through holes 10 that are rectangular in plan and long in the front-rear direction. It is perforated.

One side surface of each through hole 10 is aligned with the side surface of the protrusion 4 or the inner surface of the protrusion 3, and the other side surface of each through hole 10 is aligned with the side surface of the protrusion 8a of the terminal receiver 8. Aligned with the edge.

In addition, at the front and rear of the stand 1, so as to sandwich each terminal receptor 8,
A vertically extending through hole 11 is formed in the shape of a rectangular plane long in the horizontal direction.

Each through hole 11 is aligned with the groove 7 at the front and rear of the lower surface of the table 1, and the width of each through hole 11 in the front and rear direction is equal to the groove 7
Similarly, the width in the left and right direction is equal to the interval between each protrusion 4 or the interval between each protrusion 4 and the protrusion 3.

Thus, each terminal receiver 8 is surrounded by through holes 10, 11,
Moreover, mutually adjacent terminal receptors 8 are partitioned via protrusions 4.

12 is a cover that covers the top surface of the table 1, and a set screw 13 is inserted as appropriate.
It is fixed on the flange 3 with the flange.

Since the present invention has the above-mentioned configuration, the creepage distance between each terminal receiver is extremely large due to the presence of the protrusions and through holes. Even if the steam ejected inside the terminal box enters the terminal box and condenses on the exposed surface of the terminal block, the condensed water flows down through the through hole and does not stay on the terminal block.

Therefore, even in the event of a coolant leakage accident, there is no fear of electrical leakage, and the required withstand voltage can be sufficiently maintained, which is extremely significant.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of the present invention, FIG. 2 is a partially cutaway plan view, FIG. 3 is a bottom view, and FIG. 4 is taken along line IV-IV in FIG. 1. The cross-sectional plan view along FIG. 5 is
4 is a vertical sectional front view taken along the line ■-■ in FIG. 4, FIG. 6 is a vertical sectional side view taken along the line VI-VI in FIG. It is a diagram. 1...stand, 2...concave groove, 3...
・Protrusion, 4...Protrusion, 5...Stepped hole,
6, 7... Concave groove, 8... Terminal receiver, 8
a... Projection, 9... Set screw, 10.
11...Through hole, 12...Cover, 13
・・・・・・Set screw.

Claims (1)

[Scope of utility model registration request] On the top surface of the stand made of insulating material, a plurality of terminal receivers made of conductive material equipped with set screws for connecting terminals of electrical wiring are fixed at appropriate intervals from each other, and in the middle between each terminal receiver. A terminal block for electrical wiring, characterized in that a protrusion dividing each terminal receiver and a vertical through hole are formed.