JPS6328509Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a current-limiting fuse for a full-area high-pressure cutout, and in particular to a structure that allows the upper end of the fuse to be securely mounted and maintained airtight.

The diameter of the insulating tube of the current-limiting fuse for high-voltage cut-outs is smaller than that of the insulating tube of the general type current-limiting fuse in consideration of compatibility with the discharge type fuse tube.

For this reason, the fuse element, which is housed together with the winding core in the insulating cylinder, must be supported at the center of the cylinder, especially from the viewpoint of the thermal breakage performance.

In addition, current-limiting fuses for high-voltage cutouts are installed with the upper electrode of the fuse cylinder located above the main body of the existing high-voltage cutout installed outdoors, so rainwater from the upper electrode flows into the insulating cylinder. It is also necessary to deal with such intrusions.

The present invention is intended to solve these problems, and a fuse element 5 is connected in series with a low melting point alloy part 3 and a silver wire part 2 surrounded by an arc-extinguishing tube 4, and the fuse element 5 is spirally connected to the winding core 1. The fuse element 5 is wound up and hermetically stored in the center of the insulating cylinder 10, and both ends of the fuse element 5 are connected to upper and lower electrodes 13 and 14 provided at both upper and lower ends of the insulating cylinder 10, respectively, and an insulating space 10c inside the cylinder is connected. arc extinguisher 17
In the full-area type high-voltage cutout current limiting fuse filled with upper end 10a of
The upper electrode 13 is closely supported on the tapered locking surface 13b of the center hole 13a of the upper electrode 13, and has a heat insulating member 18 on the inside with respect to the locking surface 13b, a metal cover 19 on the outside thereof, and solder 20 on the outside thereof. The present invention proposes a current-limiting fuse for a full-area high-pressure cutout, which is characterized in that the fuse is poured into the center hole 13a to close the center hole 13a.

Examples of the present invention will be described in detail below. Reference numeral 1 denotes a pipe-shaped winding core made of cordierite or alumina sintered body, and the winding core 1 has a silver wire part 2 and a low melting point alloy part 3 connected in series as shown in the figure, and further has a low melting point alloy part 3 connected thereto in series. A fuse element 5 with an arc-extinguishing tube 4 placed around the fuse element 3 is spirally wound over its entire length, and the upper end of the element is connected to an upper terminal fitting 12 to be described later.
and the upper electrode 13 via the metal lid 19, and the lower end is connected to the lower electrode 14 via the lower terminal fitting 9. In particular, the extinguishing tube 4 is connected to the fusing display case 6 side during the winding. That is, it is wound at a position close to the lower end 10a of the insulating tube 10. The arc-extinguishing tube 4 is made of a Teflon tube or a silicon tube, and is a member that generates arc-extinguishing gas by an arc. Reference numeral 7 denotes an indicating resistance wire that is electrically connected in parallel with the fuse element 5 inserted into the winding core, and after the fuse element 5 is blown, a current is transferred to the resistance wire and the resistance wire is melted and cut. The display body 8 in the display case 6 is made to protrude from the lower end of the case. Reference numeral 9 denotes a lower part formed by fitting a ring-shaped attachment part 9a from the inside of the collar-shaped locking part 6a of the display case 6 and fixing them together with an adhesive or the like, and bending the whole body into a crank shape. The metal fitting 9 is a terminal metal fitting, and in addition to the ring-shaped attachment part 9a, the metal fitting 9 has an engaging part 9b that fits into the lower end outer surface 10a' of the insulating tube 10, and a current-carrying part 9c formed at a position opposite to the engaging part. and a connecting portion 9d at the tip thereof. The fusing indicator case 6 is made of synthetic resin, and houses the indicator 8 and a spring (not particularly shown) that biases the indicator 8 in the protrusion direction (lower end direction), and further includes a fitting portion 6b at the tip. is fitted onto the outer periphery 1a of the lower end of the winding core 1 and then fixed with adhesive 11.The winding core 1 and the case 6 are linearly connected so as to extend the winding core. Furthermore, a lower terminal fitting 9 is integrally fixed to the display case 6 with an adhesive. Reference numeral 12 denotes an upper terminal fitting which also serves as a locking member and is fitted onto the upper end 1b of the winding core 1.
When storing the metal fitting in a tapered locking surface 12a of the fitting, the tapered locking surface 13B of the center hole 13a of the upper electrode 13 fixed to the upper outer periphery 10b' of the insulating cylinder 10 is brought into close contact with the coil. The upper end side of the core is supported at the center within the insulating tube 10, and the lower end side of the core 1 is also attached to the lower terminal fitting 9, which is integrated with the display case 6. 1
The engaging part 9b and the current-carrying part 9C of the metal fitting 9 are connected to the lower end outer surface 1 of the insulating tube so as to contact the lower end surface 10a'' of the
0a' and is supported at the center of the insulating tube 10. Due to this support structure, the winding core 1 and the fuse element 5 wound around the winding core are always placed inside the insulating tube 10 made of crystallized glass or porcelain. Centrally located and supported. Reference numeral 14 denotes a lower electrode integrally fixed to the outer peripheral surface of the insulating cylinder 10 at approximately the center;
The connecting portion 14a of the electrode 14 extending toward the lower end 10a side has a connecting portion 9 of the lower terminal fitting 9.
d are connected by screws 15. The fuse element 5 housed in the insulating cylinder must have its arc-extinguishing tube 4 located close to the fuse indicator case 6 as described above. 1
Reference numeral 6 denotes a material having mechanical strength, such as Primix, which is polymerically adhered to the lower end outer surface 10a' of the insulating tube 10 where the arc extinguishing tube 4 is located, with an adhesive 21 so as to cover the lower terminal fitting 9. This is a heat-resistant reinforcing cover made of synthetic resin or the like, and the cover is formed into a bag shape with the front end open and the rear end closed.
6a, an engagement groove 16b into which the engagement part 9b of the lower terminal fitting 9 is fitted, and an engagement groove 16e into which the current-carrying part 9c is fitted.
and a display small hole 16d formed at the center of the closed rear end 16c. Reference numeral 17 denotes an arc extinguishing agent that is densely filled in the space 10c of the insulating cylinder 10, and is made of powdered quartz, alumina, or the like.
Reference numeral 18 denotes a heat insulating member 18 made of asbestos or the like, and the center hole 13a of the upper electrode 13 has a heat insulating member 18 on the inside and an overlapping member on the outside with respect to the tapered locking surface 13b of the hole 13a. The metal lid 19 is completely covered with solder 20 poured on the outside thereof. In addition,
The upper terminal fitting 12 is connected to the center hole 1 of the upper electrode 13 by the above-described heat insulating member 18, metal lid 19, and solder 20.
Falling off from 3a is prevented.

The present invention has the above-mentioned structure, and a fuse element 5 in which a low-melting point alloy part 3 and a silver wire part 2 connected in series with an arc-extinguishing tube 4 is wound spirally around a winding core 1 to form an insulating tube. Both upper and lower electrodes 1 are hermetically housed in the center of the insulating cylinder 10, and both ends of the fuse element 5 are provided at the upper and lower ends of the insulating cylinder 10.
3 and 14, and the insulating space 10c inside the cylinder is filled with an arc extinguishing agent 17. In the current limiting fuse for full-area high voltage cut-out, the core 1 has an upper terminal fitting 12 at its upper end 1b. The latch-shaped locking surface 12 of the terminal fitting 12 also fits into the terminal fitting 12.
a is tightly supported on the tapered locking surface 13b of the center hole 13a of the upper electrode 13 fixed to the upper end 10a of the insulating tube 10, and a heat insulating member 18 is placed inside the locking surface 13b, and a metal lid is placed on the outside thereof. 19 Furthermore, solder 20 is poured on the outside of the center hole 13 described above.
It consists of a current-limiting fuse for full-area high-pressure cutout, which is characterized by blocking a.
The winding core 1 and the fuse element 5 are connected to the insulating tube 1.
Of course, it can be stored in the center of the upper electrode 13 by pouring the heat insulating member 18 on the inside, the metal lid 19 on the outside, and the solder 20 on the outside.
3a, the upper terminal fitting 12 supporting the winding core 1 and the fuse element 5 is prevented from falling off the upper electrode 13 and is securely attached to the upper electrode 13 by being pressed from the outside.

At the same time, since the center hole 13a is completely covered by the heat insulating member 18, the metal lid 19, the solder 20, etc., the intrusion of rainwater etc. from the upper electrode 13 can be reliably prevented.

Further, since the heat insulating member 18 is located on the inside near the fuse element 5 to prevent the solder 20 from flowing into the insulating cylinder from the outside, assembly work is facilitated. In addition, even if the fuse element 5 arcs when the fuse is blown, the solder 20 separates and the center hole 13a becomes vacant, thereby preventing the arc and the fuse element from being ejected or scattered outside the insulating cylinder.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a current limiting fuse for high-pressure cutout showing an embodiment of the present invention, Fig. 2 is an enlarged cutaway view of the main part of the fuse element wound around the winding core, and Fig. 3 is the same as Fig. 2. Figure 4 is the left side view of Figure 3, Figure 5 is the front view of the heat-resistant reinforcing cover,
Figure 6 is a longitudinal sectional view of the same cover, Figure 7 is a right side view of Figure 6, Figure 8 is a front view of the lower terminal fitting, Figure 9 is a bottom view, and Figure 10 is a right side view. Figures are shown respectively. 1... Winding core, 1a... Lower end, 1b... Upper end, 2
...Silver wire part, 3 ...Low melting point alloy part, 4 ... Arc extinguishing tube, 5 ... Fuse element, 6 ... Fusing indicator case, 9 ... Lower terminal fitting, 9a ...
Mounting part, 9b...Engaging part, 9c...Electrifying part, 9d
... Connecting part, 10 ... Insulating tube, 10a ... Lower end,
10a'... lower end outer surface, 10b... upper end, 10c...
...Insulating space, 12... Upper terminal fitting, 12a...
Locking surface, 13... upper electrode, 13a... center hole,
13b...Locking surface, 14...Lower electrode, 17...
Arc quenching agent.

Claims (1)

[Scope of utility model registration request] Low melting point alloy part 3 covered with arc extinguishing tube 4
A fuse element 5 in which a wire and a silver wire part 2 are connected in series is spirally wound around the winding core 1 and hermetically stored in the center of the insulating tube 10. In the current-limiting fuse for full-area high-voltage cut-out, which is connected to both the upper and lower electrodes 13 and 14 provided at both ends, and in which the insulating space 10c inside the cylinder is filled with an arc extinguishing agent 17, the winding core 1 has an upper end thereof. The upper terminal fitting 12 is fitted to the upper terminal fitting 1b, and the tapered locking surface 12a of the terminal fitting 12 is connected to the tapered locking surface 13b of the center hole 13a of the upper electrode 13 fixed to the upper end 10a of the insulating tube 10. The entire area is characterized in that it closely supports the locking surface 13b and has a heat insulating member 18 on the inside, a metal lid 19 on the outside thereof, and solder 20 poured on the outside thereof to close the center hole 13a. Current-limiting fuse for high-voltage cut-outs.