JPH0245958Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Technical field) The present invention relates to current limiting fuses.

(Prior Art) As shown in Fig. 1, a conventional power fuse has a fuse element 2 made of a metal wire wound around a porcelain rod 1 in a spiral manner, and both ends of the fuse element 2 are connected to electrodes. It was connected to plates 3 and 3, respectively, and these were sealed and housed in a porcelain cylinder 4. Further, as shown in FIG. 2, a porcelain powder 5 with high arc-extinguishing properties is housed inside the porcelain cylinder 4, and electrode plates 3, 3 are connected to a plurality of fuse elements separated from each other within the porcelain powder 5. There was something that was tied with 2.

However, these conventional power fuses have a small rated current value and low breakout current value, so they do not meet recent power needs. Moreover, it is difficult to dissipate the heat generated when continuous current is applied, and furthermore, when the fuse element is blown out by the short-circuit current, the energy key increases the internal gas pressure and there is a risk that the porcelain tube 4 will burst.

(Purpose of the invention) In view of the above circumstances, the present invention aims to improve the rated current value and breakage current value of power fuses, while providing a current limiting fuse that reduces the risk of bursting, etc. be.

(Summary of the invention) Based on the above-mentioned objectives, this invention has a fuse element attached in a zigzag shape on the outer circumferential surface, and a shaft rod with electrodes on both ends is placed inside a sealed container with the electrodes remaining. In a fuse in which a wire is wound around the outer peripheral surface of the sealed container, and the fuse element and the wire are respectively connected to the electrode portion, the sealed container is made of porcelain or glass, A current limiting fuse, in which the airtight container is evacuated or an insulating material is housed, the shaft rod is made of a magnetic material, and the fuse element is wound so as not to generate magnetic flux; A current-limiting fuse formed by using the above-mentioned shaft as a hollow body and inserting and fixing a heat pipe inside the shaft;
A current limiting fuse was constructed by attaching a radiator to both ends of the shaft rod and exposing the radiator to the outside at both ends of the closed container.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 3 to 6. In the figure, reference numeral 10 denotes a closed container, which is a cylindrical body made of porcelain or glass, and an axial rod 11 is fixedly fixed through the axial center of the cylindrical body. Axle rod 11
is made of a magnetic material (ferrite, etc.), and a ribbon-shaped fuse element 12 is arranged on its outer circumferential surface in a zigzag shape so that no magnetic flux is generated inside the magnetic material rod (see Fig. 6). Adhesions are formed. Note that this shaft rod 11 may have an axial hollow portion formed therein, and a heat pipe may be embedded in the hollow portion. The shaft rods 11 protrude outside the closed container 10, and electrode portions 13 are fixed to their respective outer ends. Both ends of the fuse element 12 are connected to the electrode section 13, respectively. Further, a wire ring 14 is wound and attached to the outer peripheral surface of the closed container 10, and both ends of the wire ring 14 are connected to the electrode portions 13, respectively. On the other hand, a heat radiator 15 is attached and fixed to each of the electrode parts 13. The heat radiator 15 is provided to dissipate waste heat transferred from the shaft rod 11 to the electrode part 13 to the outside, and is a cylindrical body that is fitted and fixed to the electrode part 13 directly or indirectly through a heat conductive insulator. 16 and a plurality of fins 17 projecting radially from the cylindrical main body 16.

The inside of the airtight container 10 is maintained in a vacuum or filled with an insulating fluid such as insulating oil or SF ₆ gas, or an insulating material such as porcelain powder.

According to this configuration, the fuse element 12
Before the fuse element 12 blows out, the reactance of the fuse element 12 is made small, and all the load current passes through the fuse element 12. Next, after the fuse element 12 is fused, a current tries to flow through the wire ring 14, but since the relative magnetic permeability of the shaft rod 11 made of a magnetic material is high, the current is limited by a large reactance. In other words, it performs a current limiting action. As described above, the present invention is characterized in that current is limited by reactance. Furthermore, when the fuse element 12 blows, it is in the form of a ribbon and evaporates without a drop, so the internal pressure of the sealed container 10 does not increase. is sealed, reducing the risk of bursting. Further, the heat generated in the shaft rod 11 when continuous current is applied is efficiently dissipated by the heat pipe and the radiator 15.

(Effects of the invention) According to the invention described above, since the fuse element is formed in a ribbon shape and is attached to the shaft rod, the internal pressure of the closed container can be increased by evaporation without melting and causing drops. Moreover, since the inside of the sealed container is filled with vacuum or insulation, there is no risk of the sealed container bursting. On the other hand, the shaft rod is made of magnetic material and is attached in a zigzag shape to prevent the generation of magnetic flux in the fuse element. In addition, since the wire ring is wound around the outer circumferential surface of the sealed container, the current is passed through with a small reactance before the fuse element blows out, and the current is limited with a large reactance after the fuse element blows out, thereby reducing the rated current. In addition to improving the current value and interruption current value, it also provides a current-limiting fuse with less risk of bursting, while having a heat pipe and radiator to improve the dissipation efficiency of heat generated when continuous current is applied. be effective.

[Brief explanation of the drawing]

Figures 1 and 2 are longitudinal cross-sectional front views of the conventional example, Figure 3 is a partially cutaway front view showing an embodiment of the present invention, Figure 4 is a right side view of Figure 3, and Figure 5. 3 is a sectional view taken along the line A-A in FIG. 3, and FIG. 6 is a developed view of the adhesion formation of the fuse element. 10... airtight container, 11... shaft rod, 12... fuse element, 13... electrode section, 14... wire ring, 15... radiator.

Claims (1)

[Claims for Utility Model Registration] (1) A shaft rod having fuse elements adhered to its outer peripheral surface in a zigzag pattern and electrode portions provided at both ends is housed in a sealed container with the electrode portions remaining. , a fuse in which a wire is wound around the outer peripheral surface of the hermetically sealed container, and the fuse element and the wire are respectively connected to the electrode portion, wherein the hermetically sealed container is made of porcelain or glass; 1. A current limiting fuse, wherein the fuse element is evacuated or filled with an insulating material, the shaft rod is made of a magnetic material, and the fuse element is wound so as not to generate magnetic flux. (2) A current-limiting fuse according to claim 1 of the utility model registration, characterized in that the shaft rod is a hollow body and a heat pipe is inserted and fixed therein. (3) Utility model registration claim 1 or 2, characterized in that a radiator is attached to both ends of the shaft rod, and the radiator is exposed to the outside at both ends of the closed container. current limiting fuse.