A dual contact drop-out fuse

Abstract

The utility model discloses a kind of double contact drop-out fuse, relate to fuse technical field.A kind of double contact drop-out fuse, comprising: insulator, fuse tube, main contact and auxiliary contact;The main contact includes main static contact and main active contact, the main static contact is set to the one side of the insulator top, and the main active contact is set to the fuse tube top;The auxiliary contact includes auxiliary static contact and auxiliary active contact, the auxiliary static contact is set to the downside of the main static contact, and the auxiliary active contact is set to the one side of the fuse tube top close to the auxiliary static contact.The utility model provides a kind of double contact drop-out fuse, by installing auxiliary contact, can reduce the burn of arc to main contact, reduce the failure rate of fuse.

Description

Technical Field

[0001] This utility model relates to the field of fuse technology, and in particular to a double-contact drop-out fuse. Background Technology

[0002] Drop-out fuses and load-bearing drop-out fuses are outdoor high-voltage protective electrical appliances. They are installed on the high-voltage side of distribution transformers or on branch lines of distribution lines to provide short-circuit and overload protection for transformers and lines, as well as to switch on and off load currents.

[0003] A drop-out fuse consists of three parts: an insulator, moving and stationary contacts, and a fuse tube. The stationary contacts are installed at both ends of the insulator, and the moving contacts are installed at both ends of the fuse tube. The fuse tube consists of an inner arc-extinguishing tube and an outer phenolic paper tube or epoxy glass cloth tube. Load-bearing drop-out fuses add elastic auxiliary contacts and arc-extinguishing chambers to switch on and off load currents.

[0004] Currently, existing drop-out fuses, during opening and closing operations, push the fuse tube, and at the moment the moving contact contacts the stationary contact, the arcing current can cause burning damage to both contacts. Furthermore, prolonged exposure to wind and sun outdoors can accelerate oxidation, leading to poor contact and ultimately overheating and burnout. Utility Model Content

[0005] The purpose of this utility model embodiment is to provide a double-contact drop-out fuse. By adding an auxiliary contact, the arc burns to the main contact can be reduced, thereby lowering the failure rate of the fuse.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows: This utility model provides a double-contact drop-out fuse, including: an insulator, a fuse tube, a main contact, and a secondary contact; the main contact includes a main stationary contact and a driving contact, the main stationary contact being disposed on one side of the top of the insulator, and the driving contact being disposed on the top of the fuse tube; the secondary contact includes a secondary stationary contact and a secondary driving contact, the secondary stationary contact being disposed below the main stationary contact, and the secondary driving contact being disposed on the top of the fuse tube near the secondary stationary contact.

[0007] In some embodiments, the secondary stationary contact includes two parallel metal plates and a connecting plate connecting the two metal plates.

[0008] In some embodiments, the secondary stationary contact is made of cold-rolled steel.

[0009] In some embodiments, the auxiliary contact is a resilient metal structure.

[0010] In some embodiments, a pull-open ring is provided on the side of the fuse tube away from the secondary stationary contact.

[0011] In some embodiments, the insulator is provided with an upper incoming terminal and a lower outgoing terminal at both ends.

[0012] In some embodiments, a pressure spring is provided between the main stationary contact and the upper incoming terminal.

[0013] In some embodiments, the upper and lower parts of the insulator are respectively provided with an upper fixed bracket and a lower fixed bracket; the middle part of the insulator is provided with a middle fixed bracket.

[0014] In some embodiments, both the main stationary contact and the auxiliary stationary contact are fixedly mounted on the upper fixed bracket.

[0015] In some embodiments, a fuse is disposed inside the fuse tube.

[0016] This invention provides a double-contact drop-out fuse. By adding a secondary contact structure, and ensuring the elasticity of the secondary moving contact, the fuse can efficiently execute the arc-initiating and arc-extinguishing procedures during operation. This allows the secondary contact to make initial contact with the live conductor, thus absorbing the effects of arcing instead of the primary contact. Furthermore, based on the principle that larger contact surfaces result in lower resistance, a larger stationary contact surface is designed to reduce the resistance at the isolating switch contact point. This invention reduces arc damage to the primary contacts through the arc-initiating and arc-extinguishing functions of the secondary contact, thereby lowering the fuse failure rate and reducing replacement costs. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this disclosure, the accompanying drawings used in some embodiments of this disclosure will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual process of the method, etc. involved in the embodiments of this disclosure.

[0018] Figure 1 This is a structural diagram of a double-contact drop-out fuse in the closed position according to some embodiments of this disclosure; Figure 2 This is a structural diagram of a double-contact drop-out fuse in the open position according to some embodiments of this disclosure; Figure 3 This is a structural diagram of the auxiliary stationary contact according to some embodiments of the present disclosure; Figure 4 This is a structural diagram of the auxiliary contact according to some embodiments of the present disclosure; Figure 5This is an assembly structure diagram of the active contact and the auxiliary contact according to some embodiments of the present disclosure. Detailed Implementation

[0019] The technical solutions in some embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided in this disclosure are within the scope of protection of this disclosure.

[0020] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0021] This utility model embodiment provides a double-contact drop-out fuse, such as Figure 1 and Figure 2 As shown, it includes: insulator 1, fuse tube 2, main contact and auxiliary contact.

[0022] In some embodiments, the upper and lower parts of the insulator 1 are respectively provided with an upper fixing bracket 11 and a lower fixing bracket 12, and the middle part of the insulator 1 is provided with a middle fixing bracket 13.

[0023] For example, when using a dual-contact drop-out fuse, the fuse is mounted on a bracket via a central fixing bracket 13.

[0024] In some embodiments, the fuse tube 2 is movably connected to the insulator 1.

[0025] In some examples, such as Figure 1 and Figure 2 As shown, the lower part of the fuse tube 2 is shaft-connected to the insulator 1, and the upper part of the fuse tube 2 is movably connected to the insulator 1.

[0026] For example, such as Figure 1 and Figure 2 As shown, the lower fixed bracket 12 is fixedly provided with a hanging plate 14, and the lower part of the fuse tube 2 is connected to the hanging plate 14 through the hanging trunnion sleeve 141.

[0027] In some embodiments, the main contact includes a main stationary contact 31 and an active contact 32. The main stationary contact 31 is disposed on one side of the top end of the insulator 1, and the active contact 32 is disposed at the top end of the fuse tube 2.

[0028] For example, such as Figure 1 and Figure 2 As shown, the main stationary contact 31 is fixedly mounted on the upper fixed bracket 11. One end of the main stationary contact 31 is in the shape of a "W". When the double-contact drop-out fuse is in the closed position, the active contact 32 is located in the recess of the "W" shape of the main stationary contact 31 to prevent the active contact 32 from moving.

[0029] In some embodiments, the secondary contact includes a secondary stationary contact 41 and a secondary moving contact 42. The secondary stationary contact 41 is disposed below the main stationary contact 31, and the secondary moving contact 42 is disposed on the top of the fuse tube 2 near the secondary stationary contact 41.

[0030] For example, such as Figure 1 and Figure 2 As shown, the auxiliary stationary contact 41 is fixedly mounted on the upper fixed bracket 11. When the double-contact drop-out fuse needs to be closed, the fuse tube 2 is pushed, causing the auxiliary stationary contact 41 and the auxiliary moving contact 42 to contact first. Then, the active contact 32 is inserted into the "W"-shaped recess of the main stationary contact 31, completing the closing of the double-contact drop-out fuse. When the double-contact drop-out fuse needs to be opened, the fuse tube 2 is pulled, causing the main stationary contact 31 and the active contact 32 to separate first. Then, the auxiliary stationary contact 41 and the auxiliary moving contact 42 contact each other. The fuse tube 2 is pulled further, eventually causing the auxiliary stationary contact 41 and the auxiliary moving contact 42 to separate, completing the opening of the double-contact drop-out fuse.

[0031] In some embodiments, such as Figure 3 As shown, the auxiliary stationary contact 41 includes two parallel metal plates 411 and a connecting plate 412 connecting the two metal plates 411.

[0032] For example, such as Figure 3 As shown, two metal plates 411 are arranged in parallel, and a connecting plate 412 is disposed on the top of the two metal plates 411 and connects the two metal plates 411.

[0033] For example, the material of the secondary stationary contact 41 is cold-rolled steel.

[0034] In some embodiments, such as Figure 4 As shown, the auxiliary contact 42 is a flexible metal structure.

[0035] For example, such as Figure 4 As shown, the auxiliary contact 42 is a rectangular spring, one end of which is connected to the fuse tube 2. A rectangular spring, also known as a mold spring, is called a rectangular spring because the cross-section of the material it is made of is rectangular.

[0036] When the double-contact drop-out fuse needs to be closed, the auxiliary moving contact 42 comes into contact with the auxiliary stationary contact 41. The auxiliary moving contact 42 undergoes elastic deformation and continues to be in contact with the auxiliary stationary contact 41 until the active contact 32 is engaged in the "W"-shaped recess of the main stationary contact 31, thus completing the closing of the double-contact drop-out fuse.

[0037] In some embodiments, a pull-close ring 21 is provided on the side of the fuse tube 2 away from the secondary stationary contact 41. By pushing or pulling the fuse tube 2 through the pull-close ring 21, the main stationary contact 31 and the active contact 32, as well as the secondary stationary contact 41 and the secondary active contact 42, are closed or separated from each other.

[0038] For example, an insulating rod is inserted inside the pull ring 21 to push or pull the fuse tube 2.

[0039] In some embodiments, the insulator 1 is provided with an upper inlet terminal 5 and a lower outlet terminal 6 at its two ends.

[0040] For example, such as Figure 1 and Figure 2 As shown, the upper incoming terminal 5 is fixedly connected to the upper fixed bracket 11, and the lower outgoing terminal 6 is fixedly connected to the lower fixed bracket 12. A double-contact drop-out fuse is connected to the circuit through the upper incoming terminal 5 and the lower outgoing terminal 6.

[0041] In some examples, a pressure spring 33 is provided between the main stationary contact 31 and the upper incoming terminal 5. When the double-contact drop-out fuse is in the open position, the pressure spring 33 is in a relaxed state. When the double-contact drop-out fuse needs to be closed, the active contact 32 contacts the main stationary contact 31 and provides pressure to the main stationary contact 31. The main stationary contact 31 then compresses the pressure spring 33, causing the pressure spring 33 to undergo elastic deformation and be in a compressed state. When the active contact 32 is inserted into the "W"-shaped recess of the main stationary contact 31, the pressure spring 33 generates restoring force due to elastic deformation and provides it to the main stationary contact 31. The main stationary contact 31 presses the active contact 32 to prevent the active contact 32 from moving.

[0042] In some embodiments, a fuse tube 2 is provided inside.

[0043] For example, the fuse inside the fuse tube 2 is fixed to the mounting plate 14 and tensioned through the inside of the fuse tube 2, with the other end pressed against the active contact 32. When the fuse is affected by a large current in the circuit, it melts and then the pressure on the fuse tube 2 is reduced, causing the fuse tube 2 to fall.

[0044] This invention provides a double-contact drop-out fuse. During normal operation, pushing the fuse tube 2 sends it into the main stationary contact 31 via the auxiliary contact. The fuse wire locks the movable joint on the fuse tube 2, and the fuse tube 2 is in a closed state under the pressure of the main stationary contact 31 and is tensioned by the fuse wire. When the fuse tube 2 is pushed, the auxiliary contact makes contact first and directs the arc to the auxiliary contact head. The moving and stationary main contacts engage in the absence of an electric arc, and the main contacts will not cause arc burning when the auxiliary contact is already conducting.

[0045] In addition, when a load needs to be applied, i.e. during the tripping operation, the moving contact is opened by using an insulating rod through the pull-opening ring 21. At this time, the active contact 32 and the main stationary contact 31 separate first, while the auxiliary moving contact 42 and the auxiliary stationary contact 41 remain in contact. There is no arc burning on the moving and stationary main contacts, thus protecting the two main contacts. If the auxiliary moving contact 42 is pulled further, the auxiliary moving contact 42 and the auxiliary stationary contact 41 also separate, and an arc is generated between the auxiliary moving contact 42 and the auxiliary stationary contact 41. The arc is drawn and elongated in the extinguishing chamber slit. At the same time, the fuse tube 2 generates gas, which extinguishes the arc when the current crosses zero.

[0046] When a circuit system malfunctions, the fault current causes the fuse to melt rapidly, forming an electric arc. The arc-extinguishing tube is heated by the arc, decomposing and releasing a large amount of gas, creating high pressure inside the tube and causing a longitudinal blow along the pipe. The arc is rapidly elongated and extinguished. After the fuse melts, the lower part of the fuse tube 2 loses tension and flips downwards, locking the mechanism and releasing the fuse tube 2. The fuse tube 2 falls, forming a clear break point.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Any other modifications or equivalent substitutions made by those skilled in the art to the technical solution of this utility model, as long as they do not depart from the spirit and scope of the technical solution of this utility model, should be covered within the scope of the claims of this utility model.

Claims

1. A double-contact drop-out fuse, characterized in that: include: Insulators, fuse tubes, main contacts, and auxiliary contacts; The main contact includes a main stationary contact and an active contact. The main stationary contact is disposed on one side of the top of the insulator, and the active contact is disposed at the top of the fuse tube. The auxiliary contact includes an auxiliary stationary contact and an auxiliary moving contact. The auxiliary stationary contact is located below the main stationary contact, and the auxiliary moving contact is located at the top of the fuse tube near the auxiliary stationary contact. The auxiliary stationary contact includes two parallel metal plates and a connecting plate connecting the two metal plates. The auxiliary moving contact is a flexible metal structure. The insulator is equipped with an upper fixed bracket and a lower fixed bracket, respectively. The auxiliary stationary contact is fixedly mounted on the upper fixed bracket. When the double-contact drop-out fuse needs to be closed, the fuse tube is pushed, causing the auxiliary stationary contact and the auxiliary moving contact to make contact first. Then, the moving contact is inserted into the W-shaped recess of the main stationary contact, completing the closing of the double-contact drop-out fuse. When the double-contact drop-out fuse needs to be opened, the fuse tube is pulled, causing the main stationary contact and the moving contact to separate first. Then, the auxiliary stationary contact and the auxiliary moving contact make contact. The fuse tube is pulled further, finally causing the auxiliary stationary contact and the auxiliary moving contact to separate, completing the opening of the double-contact drop-out fuse. The lower fixed bracket is fixedly equipped with a mounting plate, and the lower part of the fuse tube is connected to the mounting plate through a mounting trunnion sleeve. The fuse tube is equipped with a fuse wire inside, which is fixed to the mounting plate and tensioned through the inside of the fuse tube. The other end is pressed against the active contact. When the fuse wire is affected by the large current in the circuit, it will melt and break, reducing the pressure on the fuse tube and causing the fuse tube to fall.

2. The double-contact drop-out fuse as described in claim 1, characterized in that, The material of the auxiliary stationary contact is cold-rolled steel.

3. The double-contact drop-out fuse as described in claim 1, characterized in that, A pull-opening ring is provided on the top of the fuse tube on the side away from the auxiliary stationary contact.

4. The double-contact drop-out fuse as described in claim 1, characterized in that, The insulator is provided with an upper incoming terminal and a lower outgoing terminal at both ends.

5. The double-contact drop-out fuse as described in claim 4, characterized in that, A pressure spring is provided between the main stationary contact and the upper incoming terminal.

6. The double-contact drop-out fuse as described in claim 1, characterized in that, The insulator is provided with an upper fixed bracket and a lower fixed bracket at its upper and lower parts, respectively; and a middle fixed bracket is provided at the middle part of the insulator.

7. The double-contact drop-out fuse as described in claim 6, characterized in that, Both the main stationary contact and the auxiliary stationary contact are fixedly mounted on the upper fixed bracket.

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