JPS6328510Y2 - - Google Patents

Description

[Detailed explanation of the invention] This invention is a highly safe all-area type that minimizes the destruction of the insulating tube even if it becomes impossible to cut the insulation at low magnification. This paper attempts to propose a current-limiting fuse for high-pressure cutouts. In the current limiting fuse for full-area high-voltage cutout, the diameter of the insulating tube is made the same as that of the conventionally used discharge type fuse tube in consideration of compatibility. Therefore, the diameter of the insulating tube was much smaller than that of the insulating tube of a general current limiting fuse. Therefore, if the fuse element, which is housed together with the winding core in the insulating cylinder, is assembled with even a slight eccentricity during assembly, the arc-extinguishing agent filled in the insulating cylinder may become unevenly filled, or the fuse may The element may come into contact with the inner surface of the insulating tube, which may impede the cooling effect and cause insufficient insulation recovery, or if the arc continues, the insulating tube may be damaged by uneven heat, resulting in low magnification (rated 5 of current
In some cases, the current value was about twice as high as the current value). The present invention is designed to prevent as much as possible the worst situation in which the insulating tube breaks and scatters even if the above-mentioned failure occurs. A fuse element 5, in which a fuse element 5 and a silver wire part 2 are connected in series, is spirally wound around a winding core 1 to form an insulating tube 1.
The element 5 is hermetically housed in the center of the tube, and both ends of the element 5 are connected to upper and lower electrodes 13 and 14 fixed to the upper and lower ends of the insulating tube 10, respectively, and an arc extinguishing agent 17 is placed in the insulating space 10c inside the tube. In the full-area type high-voltage cutout current limiting fuse filled with A lower end portion of an insulating cylinder of a current limiting fuse for full-area high-voltage cutout, characterized in that the periphery of the lower terminal fitting 9 is reinforced with a bag-shaped heat-resistant reinforcing cover 16 that is polymerized and adhered to the outside of the lower terminal fitting 9 via an adhesive 21. This paper proposes a mounting structure for. 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 an adhesive 11.The winding core 1 and the case 6 are linearly connected 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 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 fixed integrally to the outer circumferential surface of the insulating tube 10 at approximately the center thereof, and a connecting portion 14a of the electrode 14 extending toward the lower end 10a of the insulating tube 10 has a connecting portion for the lower terminal fitting 9. 9d
are connected by screws 15. In addition, the fuse element 5 housed in the insulating cylinder has its arc-extinguishing tube 4 inserted into the fuse indicator case 6 as described above.
It is necessary to locate it close to the side. 16
is a synthetic 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 resin or the like, and the cover is formed into a bag shape with the front end open and the rear end closed, and has a cutout 16 where the connection part 14a of the lower electrode 14 is located.
a, an engagement groove 16b into which the engagement part 9b of the lower terminal fitting 9 fits, and an engagement groove 16e into which the current-carrying part 9c fits.
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.
18 is a heat insulating member such as asbestos that closes the center hole 13a of the upper electrode, 19 is a metal lid stacked on the heat insulating member 18 from the outside, and 20 is solder. As described above, the present invention has an arc-extinguishing tube 4 around it.
A fuse element 5 in which a low melting point alloy 3 covered with a metal wire and a silver wire part 2 are connected in series is spirally wound around a winding core 1 and hermetically stored in the center of an insulating tube 10, and both ends of the element 5 are 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 fixed to the upper and lower ends of the insulating cylinder 10, and the insulating space 10c inside the cylinder is filled with arc-extinguishing agent 17, the above-mentioned extinguisher is used. arc tube 4
A lower electrode 14 is fixed to the lower outer periphery of the insulating cylinder 10.
In addition, the insulating cylinder 10 is further positioned on the lower end side, and the entire circumference of the lower end side of the insulating cylinder 10 is reinforced with a bag-shaped heat-resistant reinforcing cover 16 from the outside of the lower terminal fitting 9 via an adhesive 21. It consists of a mounting structure at the lower end of the insulating tube of the current-limiting fuse for full-area high-voltage cutout, which is characterized by the following: Also, since the heat-resistant reinforcing cover 16 is polymerized and adhered to the outside of the insulating tube, the insulating tube has the advantage that damage to the insulating tube can be limited to minor damage such as cracking. Further, the lower terminal fitting 9 located on the outer periphery of the lower end of the insulating tube 10 is pressed and fixed from the outside with the heat-resistant reinforcing cover 16 as described above, and the adhesive 21
Because it is fixed in place, it prevents it from bending, accidentally tripping, or catching when handling.

[Brief explanation of drawings]

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, 2... Silver wire part, 3
...Low melting point alloy part, 4 ... Arc extinguishing tube, 5 ...
Fuse element, 6... Fusing indicator case, 6a... Locking part, 9... Lower terminal fitting, 9a
...Mounting part, 9b...Engaging part, 9c...Electrifying part,
9d... Connecting portion, 10... Insulating cylinder, 10a'... Lower end outer surface, 10a''... Lower end surface, 10c... Insulating space, 13... Upper electrode, 14... Lower electrode, 14
a...Connection part, 16...Heat-resistant reinforcement cover, 16
d...Small hole for display body, 17...Arc extinguisher, 21...
Adhesive material.

Claims (1)

[Scope of utility model registration request] An insulating tube 1 is formed by winding a fuse element 5 in which a low melting point alloy 3 with an arc extinguishing tube 4 surrounding it and a silver wire portion 2 connected in series is spirally wound around a winding core 1.
The element 5 is hermetically housed in the center of the tube, and both ends of the element 5 are connected to upper and lower electrodes 13 and 14 fixed to the upper and lower ends of the insulating tube 10, respectively, and an arc extinguishing agent 17 is placed in the insulating space 10c inside the tube. In the full-area type high-voltage cutout current limiting fuse filled with A lower end portion of an insulating cylinder of a current limiting fuse for full-area high-voltage cutout, characterized in that the periphery of the lower terminal fitting 9 is reinforced with a bag-shaped heat-resistant reinforcing cover 16 that is polymerized and adhered to the outside of the lower terminal fitting 9 via an adhesive 21. Mounting structure in.