JPS6253068B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to the structure of a terminal block for a power meter.

[Technical background of the invention and its problems]

The terminal block of the watt-hour meter is made by molding an insulating material, and after incorporating terminal fittings, terminal screws, packing, etc., is attached to the lower part of the base of the watt-hour meter. FIG. 1 is a perspective view of a terminal block 1 incorporating a terminal fitting 2 and a terminal screw 3, seen from the front. 2 is a perspective view of the conventional terminal block 1 seen from the rear, and FIG. 3 is a perspective view of the conventional terminal block 1.
is shown attached to the base 5 of the electricity meter,
FIG. 3 is a sectional view taken along a plane including the terminal screw.

The structure of a conventional terminal block will be explained with reference to FIGS. 1 to 3. The terminal block 1 is formed as a rectangular parallelepiped block as a whole, and the front side of the four sides around the longitudinal axis of this block is
Recesses 13 for operating terminal screws are arranged on both sides of the seat surface 11 having holes 12 for mounting screws.
The upper surface of the block has a radial convex edge 14a at the bottom that communicates with the terminal screw operation recess 13 at each side.
Terminal fitting insertion holes 14 having a diameter of 15 mm are distributed in the upper surface of the block in a direction perpendicular to the upper surface of the block. Furthermore, there is a terminal fitting insertion hole 1 on the top surface of the block.
Insulating bank 1 extending in front of all of 4
5 is provided protrudingly.

A plurality of wire insertion holes 16 are opened on the lower surface of the block, each communicating with the bottom of each terminal fitting insertion hole 14. Further, on the back surface of the block, an upper convex edge 17 and a lower convex edge 18, which are equal in height from the back surface, are provided at the upper and lower ends thereof, respectively, and extend in the longitudinal axis direction of the block. In addition,
The lower convex edge 18 is cut out over a predetermined length in the central portion where the mounting screw hole 12 is bored. As shown in FIG. 3, the upper convex edge 17 and the lower convex edge 18 serve as seating surfaces that come into contact with the terminal block guide 6 that is welded and fixed to the base 5 when the terminal block 1 is attached to the base 5. , if the heights of the convex edges 17 and 18 are different, the terminal block 1
is tilted, and the tightening force of the gasket 4 between the base 5 and the terminal block 1 becomes uneven, resulting in water seepage. For this reason, the upper convex edge 17 and the lower convex edge are made equal in height. In addition, each of the upper and lower convex edges 17,
Terminal block 1 has 18 as its mounting surface.
This is to make the wall thickness of the block as uniform as possible as a whole to prevent cavities from forming during molding.

Further, the terminal fitting 2 is inserted into the terminal fitting insertion hole 14 from above and attached to the terminal block 1, and comes into contact with the convex edge 14a at the bottom of the terminal fitting insertion hole 14 to be prevented from coming out downward. Then, the terminal screw 3 is screwed into the terminal fitting 2 through the communicating portion of the side portion of the terminal fitting insertion hole 14 that communicates with the terminal screw operation recess 13. For the wire, insert the wire into the wire insertion hole 1 on the bottom of the terminal block 1.
6, enters the wire insertion hole 2a of the terminal fitting 2, and is fixed with the terminal screw 3.

The fourth figure shows the arrangement of molds when molding the conventional terminal block 1 having the above structure.
In the figure, the mold needs to be divided into four directions: a mold 7a for the front surface of the terminal block 1, a mold 7b for the top surface, a mold 7c for the bottom surface, and a mold 7d for the rear surface. This is because the terminal block 1 has a terminal screw operation recess 13 on the front surface, a protruding edge 14a at the bottom of a terminal fitting insertion hole 14 drilled in the upper surface, and a step formed by the protruding edge 14a on the lower surface. This is due to the structure in which there is a wire insertion hole 16 attached thereto, and a thin recessed portion brought about by the presence of the upper convex edge 17 and the lower convex edge 18 is formed on the back surface.

Therefore, the terminal block 1 is molded using a mold that is divided into four parts and opened in four directions as shown by the arrows in the figure. In this way, for each terminal block, 4
Since it is necessary to mold using molds from different directions, only one row of terminal blocks can be molded using one set of molds, as shown in FIG. For this reason, there has been a major restriction when molding a large number of terminal blocks with one set of molds for the purpose of reducing the cost of terminal blocks and improving yield.

[Purpose of the invention]

The present invention improves the structure of the terminal block so that it can be molded by a three-part mold that opens in three directions, and in the case of multi-piece molding, an arrangement of molds in which two terminal blocks are placed back to back can be used. The object of the present invention is to provide a terminal block for a power meter that can double the processing capacity.

[Summary of the invention]

The present invention provides recesses for operating terminal screws disposed on both sides of a seating surface having holes for mounting screws on the front surface of the four faces around the longitudinal axis of a rectangular parallelepiped block made of an insulating material, and these recesses. A plurality of terminal fitting insertion holes, each having a radial convex edge at the bottom and communicating with each other at the sides thereof, are bored in the upper surface of the block in a direction perpendicular to the upper surface of the block, and the front surface of these terminal fitting insertion holes. an insulating bank extending laterally and protruding from the top surface of the block; a plurality of wire insertion holes opening at the bottom surface of the block and communicating with the bottoms of the terminal fitting insertion holes; and a lower end of the back surface of the block. a lower convex edge extending in the longitudinal axis direction except for a predetermined length in the center and protruding from the back surface by a predetermined height; Realizing a terminal block for a watt-hour meter, comprising a plurality of vertical edges that are spaced apart from each other and protrude from the upper surface of the block to the lower convex edge, and whose height from the back surface is equal to that of the lower convex edge, By integrating the molds for molding the top and back surfaces of the block, we were able to achieve the desired purpose by making it possible to mold with a three-part mold that opens on three sides.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 6 is a perspective view of a terminal block of a watt-hour meter according to an embodiment of the present invention, seen from the back side, and FIG. 7 is a sectional view showing the terminal block of FIG. 6 attached to the base of the watt-hour meter. .

A terminal block 1' according to an embodiment of the present invention is the same as the terminal block shown in FIG. 1 except for the structure on the back side, and the same parts are given the same reference numerals and their explanation will be omitted. As shown in FIG. 6, on the back surface of the terminal block, a lower convex edge 21 is formed at the lower end thereof, extending in the longitudinal axis direction except for a predetermined length in the center and protruding from the back surface by a predetermined height. . Further, on the back surface of the block, four vertical ridges 22 are provided extending from the top surface of the block to the convex edge 21, spaced apart from each other in the longitudinal axis direction of the block, avoiding the central mounting screw hole. The height of each of the ridges 22 from the back surface is equal to the height of the lower convex edge 21. As shown in FIG. 7, each vertical ridge 22 and convex edge 21 serve as a seating surface that comes into contact with the terminal block guide 6 of the base 5 when the terminal block 1' is attached to the base 5. The heights of the lower convex edges 21 are made equal to prevent the terminal block 1' from tilting with respect to the base 5, so that the tightening force of the packing 4 is made uniform. In addition, by forming the vertical ridge 22 and the lower convex edge 21 as a mounting seat surface,
The wall thickness of the block 1' is made as uniform as possible as a whole to prevent the formation of cavities during molding.

FIG. 8 shows the arrangement of molds when molding a terminal block 1' according to an embodiment of the present invention having the above-described structure. The mold can be divided into three directions: mold 7a for the top and back surfaces, mold 7'b for the bottom surface, and mold 7'c for the bottom surface.Moreover, by arranging the blocks 1' back to back, the mold 7a for the front surface can be separated. Just by adding, two terminal blocks can be obtained by one molding. We were able to reduce the number of mold divisions in this way by changing the structure of the mounting seat on the back side to 22 vertical ridges.
This is because the upper convex edge in the longitudinal axis direction at the upper end of the back surface is eliminated by combining the lower convex edge 21 at the lower end.

As a result, even when making a mold with multiple cavities, the 9th
As shown in the figure, by arranging back-to-back molds side by side, it is possible to obtain twice the processing capacity with a mold of the same size as conventional molds.

〔Effect of the invention〕

As described in detail above, according to the present invention, the structure of the back surface of the block, which serves as the mounting surface for mounting the terminal block of the watt-hour meter to the watt-hour meter base, is adjusted so that the bottom end a lower protruding edge protruding from the block, and a plurality of vertical ridges protruding from the upper surface of the block across the lower protruding edge, spaced apart from each other in the longitudinal axis direction, avoiding the mounting screw hole in the center of the block. By making each of these vertical edges and the lower convex edge equal in height from the back surface, a conventional terminal block can be protruded from the upper end of the back surface extending in the longitudinal axis direction (horizontal direction). The disadvantage that the terminal block of the present invention had to open the mold on the back side in a direction perpendicular to the back surface due to the convex edge on the top has been solved, and in the terminal block according to the present invention, the mold on the back side can be opened in a direction parallel to the back surface. It was possible to integrate it with the upper mold. As a result, the mold can be divided into three directions: a mold for the front surface of the terminal block, a mold for the top and back surfaces, and a mold for the bottom surface. and,
Two terminal blocks can be obtained by one molding process simply by placing the back sides of two terminal blocks back to back and adding a mold for the front side. Furthermore, in the case of multi-piece molding, by arranging the molds in which two terminal blocks are arranged back to back, it is possible to obtain twice the processing capacity with a mold of the same size as conventional molds.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a terminal block incorporating terminal fittings and terminal screws, seen from the front, Figure 2 is a perspective view of a conventional terminal block seen from the back, and Figure 3 shows the terminal block of Figure 2. A cross-sectional view of the plane including the terminal screws, showing the power meter installed on the base.
Fig. 4 is a sectional view showing the arrangement of the mold for molding the conventional terminal block shown in Fig. 2, and Fig. 5 is an explanation showing the arrangement in the case of multi-piece molding using the mold of Fig. 4. 6 is a perspective view of the terminal block of a watt-hour meter according to an embodiment of the present invention, seen from the back side, and FIG. 7 shows the terminal block of FIG. 6 attached to the base of the watt-hour meter, and the terminal screws 8 is a sectional view showing the arrangement of a mold for molding the terminal block of the embodiment of the present invention shown in FIG. 6, and FIG. It is an explanatory view showing the arrangement of molds in the case of multiple molds used. 1'...Terminal block, 2...Terminal fitting, 3...
...terminal screw, 4...packet, 5...base of electricity meter, 6...block guide, 11...seating surface,
12... Hole for mounting screw, 13... Recess for terminal screw operation, 14... Terminal fitting insertion hole, 14a... Convex edge, 15... Insulating bank, 16... Electric wire insertion hole, 21
... Lower convex edge, 22 ... Vertical edge, 7a ... Mold for front surface, 7'b ... Mold for upper and back surfaces, 7'c ...
Mold for the bottom surface.

Claims (1)

[Claims] 1 Recesses for operating terminal screws located on both sides of the seating surface having holes for mounting screws on the front of the four sides around the longitudinal axis of a rectangular parallelepiped block made of insulating material; A plurality of terminal fitting insertion holes are formed in the upper surface of the block in a direction perpendicular to the upper surface of the block, and the terminal fitting insertion holes have a convex edge in the radial direction at the bottom thereof. an insulating bank protruding from the top surface of the block, a plurality of wire insertion holes opening at the bottom surface of the block and communicating with the bottoms of the terminal fitting insertion holes, and a longitudinal axis provided at the bottom end of the back surface of the block. a lower convex edge extending in the direction other than a predetermined length in the center and protruding from the back surface by a predetermined height; A terminal block for a power meter, comprising a plurality of vertical edges projecting from the upper surface of the block over the lower convex edge and having a height from the back surface equal to the lower convex edge.