Enclosed fuse

Abstract

The utility model relates to a closed fuse which comprises a porcelain tube, and two ends of the porcelain tube are respectively provided with a first threaded hole and a second threaded hole. The diameter of the first threaded hole is larger than that of the second threaded hole, a first contact knife terminal is in threaded connection in the first threaded hole, and a second contact knife terminal is in threaded connection in the second threaded hole; the porcelain tube is internally provided with a melt and is filled with an arc extinguishing medium, and two ends of the melt are respectively welded with the inner sides of the first contact knife terminal and the second contact knife terminal. The utility model is easy to assemble and disassemble, and the quality of the assembled product is stable.

Description

Technical Field

[0001] The utility model belongs to the technical field of fuses, and in particular relates to a closed fuse. Background Art

[0002] A fuse is a component that protects the equipment and instruments in the circuit by melting the fuse with the heat it generates or disconnecting the fuse mechanically after the current exceeds the specified value for a period of time, thereby disconnecting the circuit. Fuses are widely used in high and low voltage power distribution systems and control systems, electrical equipment, and new energy vehicles. As a short circuit and overcurrent protector, they are one of the most commonly used protection devices. Fuses can be divided into pluggable fuses and hook fuses according to the way the contact blade is connected to the circuit. They can be divided into naked type, semi-enclosed type, and fully enclosed type according to the structure. There are also filled fuses and unfilled fuses according to whether there is filler. The main structures of these fuses include a shell, a fuse arranged in the shell, and a contact blade located outside the shell and connected to the fuse.

[0003] At present, the existing closed square tube fuses need to use screws to connect the cover plate, gasket, contact knife, porcelain tube and other parts. The round tube fuses need to be drilled and fixed with pins after passing through the tube. There are many assembly actions, and the cost of automated production investment is high. Production mainly relies on manual assembly lines, and it is difficult to guarantee the stability of product quality. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a closed fuse which is easy to assemble and disassemble, and the quality of the assembled product is stable.

[0005] In order to achieve the above object, the technical solution of the utility model is:

[0006] A closed fuse comprises a porcelain tube, wherein a first threaded hole and a second threaded hole are respectively formed at two ends of the porcelain tube; the diameter of the first threaded hole is greater than the diameter of the second threaded hole, and a first contact terminal is threadedly connected in the first threaded hole, and a second contact terminal is threadedly connected in the second threaded hole; a melt is arranged in the porcelain tube and is filled with an arc extinguishing medium, and the two ends of the melt are respectively welded to the inner sides of the first contact terminal and the second contact terminal.

[0007] In the above-mentioned enclosed fuse, the first contact terminal is respectively provided with a first large plug hole and a first small plug hole, and the second contact terminal is respectively provided with a second large plug hole and a second small plug hole; the first large plug hole corresponds to the second small plug hole, and the first small plug hole corresponds to the second large plug hole.

[0008] The above-mentioned enclosed fuse has a first contact terminal connected to a DC circuit or an AC circuit, and a second contact terminal connected to a load.

[0009] Technical effects and advantages of the utility model:

[0010] The utility model provides a closed fuse, in which threaded holes are respectively arranged at the two ends of a porcelain tube, so that a contact terminal can be threadedly connected to the threaded hole. During assembly, after the fuse and the terminal are welded, the fuse can be directly loaded into the porcelain tube through the threaded hole, and the contact terminal can be threadedly connected to the two ends of the porcelain tube respectively to seal the fuse. The assembly is convenient and quick, and the fuse and the contact terminal can be welded in advance under the condition of easy welding, so that the quality of the assembled product is stable. Compared with the existing closed square fuse and closed round tube fuse, the assembly action of the square fuse cover and the gasket and the pressing action of the round tube fuse pin are simplified, and the use of the cover, the gasket and the pin is omitted, thereby saving costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a cross-sectional structural schematic diagram of the utility model;

[0012] Figure 2 It is a schematic structural diagram of the utility model in which the porcelain tube is a cube;

[0013] Figure 3 It is a structural schematic diagram of the utility model in which the porcelain tube is a round tube;

[0014] Figure 4 This is a schematic diagram of the welding structure of the melt and the contact knife terminal of the utility model;

[0015] Figure 5 It is a schematic diagram of fixing and positioning the first contact knife terminal and the second contact knife terminal during melt welding of the utility model.

[0016] Numbers in the figure: 1, first knife contact terminal; 11, first large plug hole; 12, first small plug hole; 2, second knife contact terminal; 21, second large plug hole; 22, second small plug hole; 3, porcelain tube; 31, first threaded hole; 32, second threaded hole; 4, retaining rod; 5, quick latch. DETAILED DESCRIPTION

[0017] The present invention will be further described in detail below with reference to the embodiments given in the accompanying drawings.

[0018] See also Figure 1As shown, a closed fuse includes a porcelain tube 3, and a first threaded hole 31 and a second threaded hole 32 are respectively opened at both ends of the porcelain tube 3; the diameter of the first threaded hole 31 is larger than the diameter of the second threaded hole 32, and a first contact terminal 1 is threadedly connected in the first threaded hole 31, and a second contact terminal 2 is threadedly connected in the second threaded hole 32; a melt is arranged in the porcelain tube 3, and is filled with an arc extinguishing medium, and the two ends of the melt are respectively welded to the inner sides of the first contact terminal 1 and the second contact terminal 2.

[0019] Specifically, by respectively providing a first threaded hole 31 and a second threaded hole 32 at both ends of the porcelain tube 3, the first contact terminal 1 and the second contact terminal 2 can be threadedly connected to the porcelain tube 3. During assembly, after the fuse is welded to the first contact terminal 1 and the second contact terminal 2, the fuse can be directly loaded into the porcelain tube 3 through the first threaded hole 31, and the first contact terminal 1 and the second contact terminal 2 can be threadedly connected to the two ends of the porcelain tube 3 respectively, so that the fuse is sealed, and the assembly is convenient and quick, and the fuse can be welded to the first contact terminal 1 and the second contact terminal 2 in advance when it is easy to weld, so that the quality of the assembled product is stable.

[0020] Preferably, in order to ensure stable assembly quality of the product, a first large plug hole 11 and a first small plug hole 12 are respectively opened on the first contact terminal 1, and a second large plug hole 21 and a second small plug hole 22 are respectively opened on the second contact terminal 2; the first large plug hole 11 corresponds to the second small plug hole 22, and the first small plug hole 12 corresponds to the second large plug hole 21.

[0021] When assembling the utility model, refer to Figure 5 , Figure 4 As shown, first, the thin end of a holding rod 4 is passed through the first large plug hole 11 and the second small plug hole 22 in sequence, so that the plug hole opened on the thin end is exposed outside the second contact terminal 2, and the quick plug 5 is inserted into the plug hole for the first fixed positioning; the thin end of the second holding rod 4 is passed through the second large plug hole 21 and the first small plug hole 12 in sequence, so that the plug hole opened on the thin end is exposed outside the first contact terminal 1, and the quick plug 5 is inserted into the plug hole for the second fixed positioning, thereby completing the positioning of the first contact terminal 1 and the second contact terminal 2;

[0022] The second step is to place the melt between the first contact terminal 1 and the second contact terminal 2, so that both ends of the melt are in contact with the first contact terminal 1 and the second contact terminal 2, respectively, and then spot weld the two ends of the melt to the first contact terminal 1 and the second contact terminal 2, respectively, to complete the assembly of the melt and the contact terminals;

[0023] The third step is to assemble the assembly completed in the second step into the porcelain tube 3. The specific assembly method is: insert one end of the second contact terminal 2 through the first threaded hole 31 and pass through the second threaded hole 32, and rotate the first contact terminal 1 and the second contact terminal 2 at the same time, and thread the first contact terminal 1 and the second contact terminal 2 to the first threaded hole 31 and the second threaded hole 32 respectively; then pull out the quick plug 5, take out the retaining rod 4, and complete the assembly of the enclosed fuse.

[0024] See also Figure 2 , Figure 3 As shown, the enclosed fuse of the present application can be applied to both enclosed cubic fuses and enclosed fuses of round tubes. Both cubic fuses and round tube fuses can adopt the above-mentioned assembly method.

[0025] The first contact blade terminal 1 of the enclosed fuse of the present application is used to connect to a DC circuit or an AC circuit, and the second contact blade terminal 2 is connected to a load to protect the circuit from damage caused by overload and short circuit. Common application scenarios include household circuits, industrial control systems, rail transit power grid systems, semiconductor current-carrying equipment, power systems, electrical equipment, electric vehicle high-voltage electrical systems, and charging equipment protection systems.

[0026] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, and these modifications and improvements all fall within the protection scope of the present invention.

Claims

1. A closed fuse, characterized in that: The invention comprises a porcelain tube (3), wherein two ends of the porcelain tube (3) are respectively provided with a first threaded hole (31) and a second threaded hole (32); the diameter of the first threaded hole (31) is larger than the diameter of the second threaded hole (32), and a first contact terminal (1) is threadedly connected to the first threaded hole (31), and a second contact terminal (2) is threadedly connected to the second threaded hole (32); a melt is provided in the porcelain tube (3) and is filled with an arc extinguishing medium, and the two ends of the melt are respectively welded to the inner sides of the first contact terminal (1) and the second contact terminal (2).

2. A closed fuse according to claim 1, characterized in that: The first contact terminal (1) is provided with a first large plug hole (11) and a first small plug hole (12), and the second contact terminal (2) is provided with a second large plug hole (21) and a second small plug hole (22); the first large plug hole (11) corresponds to the second small plug hole (22), and the first small plug hole (12) corresponds to the second large plug hole (21).

3. A closed fuse according to claim 2, characterized in that: The first contact terminal (1) of the enclosed fuse is connected to a DC circuit or an AC circuit, and the second contact terminal (2) is connected to a load.

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