Full-range protection fuse

Abstract

The invention relates to a fuse, in particular to a full-range protection fuse, which is characterized in that an overload fuse and a short-circuit fuse are arranged in a fusion tube, overload welding plates are arranged at two ends of the overload fuse, and short-circuit welding plates are arranged at two ends of the short-circuit fuse; a switching mechanism is slidably mounted between the short-circuit welding plate and the overload welding plate in the same end cover, and the switching mechanism is connected with the overload welding plate in an initial state; an electromagnetic coil is arranged in the end cover, one end of the electromagnetic coil is connected with the wiring terminal, and the other end is connected with the switching mechanism; when short-circuit current is connected to the connecting terminal, the short-circuit current passes through the electromagnetic coil and the switching mechanism, the electromagnetic coil drives the switching mechanism to be separated from the overload welding plate and connected with the short-circuit welding plate, the overload fuse is switched to the short-circuit fuse, and the short-circuit fuse breaks the short-circuit current. The full-range protection fuse provided by the invention can be suitable for current breaking of overload of different multiples.

Description

Technical Field

[0001] The invention relates to a fuse, in particular to a full-range protection fuse. Background Art

[0002] Fuses, commonly known as "fuses", are key overcurrent protection components in power systems and are widely used in power distribution and control systems. Their main function is to prevent damage caused by short circuits and overloads. The current mainstream thermal fuse structure includes components such as an insulating tube body, terminals, a cover plate, a fuse and an arc-extinguishing medium. Its working principle is based on the thermal effect of current: under rated voltage, heat is generated when current flows through the fuse. When the heat accumulates to a specific area of ​​the fuse (i.e., the narrow diameter) and reaches the melting point, the area will melt and disconnect the circuit, thereby quickly cutting off the fault current and protecting the system safety.

[0003] According to the different protection capabilities, fuses can be divided into two categories:

[0004] Full range protection fuse (Class G fuse): Suitable for low overload and small breaking current scenarios. Although it can provide more comprehensive protection, its breaking capacity is limited, generally not exceeding 100kA.

[0005] Partial range protection fuse (Class A fuse): Good at handling large breaking currents up to 300kA, but insufficient protection for small overload currents below 5 times, and there is a protection blind spot.

[0006] In view of the limitations of the above two types of fuses, there is an urgent need for an all-round fuse that can cover the full range of overload currents (including small and large multiples) and achieve effective disconnection to meet the complex and changing power protection needs. Summary of the invention

[0007] The purpose of the present invention is to solve the technical problem that the existing fuses are difficult to be applied to the interruption of overload currents of different multiples, and to provide a full-range protection fuse.

[0008] To solve the above technical problems, the technical solutions provided by the present invention are as follows:

[0009] A full range protection fuse includes a fuse tube, both ends of which are provided with end caps with connection terminals;

[0010] An overload fuse and a short-circuit fuse are arranged in the melting tube, overload welding plates are arranged at both ends of the overload fuse, and short-circuit welding plates are arranged at both ends of the short-circuit fuse;

[0011] A switching mechanism is slidably installed between the short-circuit welding plate and the overload welding plate in the same end cover. In an initial state, the switching mechanism is connected to the overload welding plate.

[0012] An electromagnetic coil is arranged in the end cover, one end of the electromagnetic coil is connected to the wiring terminal, and the other end is connected to the switching mechanism;

[0013] When the connecting terminal is connected to the short-circuit current, the short-circuit current passes through the electromagnetic coil and the switching mechanism. The electromagnetic coil drives the switching mechanism to separate from the overload welding plate and connect to the short-circuit welding plate, switching the overload fuse to the short-circuit fuse, and the short-circuit fuse disconnects the short-circuit current.

[0014] Furthermore, the switching mechanism includes a push plate, and a short-circuit step and an overload step distributed on both sides of the push plate; the short-circuit step is connected to the short-circuit welding plate, and the overload step is connected to the overload welding plate;

[0015] In the initial state, the push plate is connected to the overload step;

[0016] When the connecting terminal is connected to the short-circuit current, the short-circuit current passes through the electromagnetic coil and the push plate. The electromagnetic coil drives the push plate to separate from the overload step and connect to the short-circuit step, switching the overload fuse to the short-circuit fuse, and the short-circuit fuse disconnects the short-circuit current.

[0017] Furthermore, a plurality of convex humps are provided on both sides of the push plate; one side of the push plate can be connected to the short-circuit step through the plurality of convex humps, and the other side of the push plate can be connected to the overload step through the plurality of convex humps.

[0018] Furthermore, slide grooves are provided on the sides of the overload welding plate and the short-circuit welding plate close to each other in the same end cover; the short-circuit step is installed in the slide groove of the short-circuit welding plate, and the overload step is installed in the slide groove of the overload welding plate;

[0019] The push plate is slidably installed between the short-circuit welding plate and the overload welding plate through the sliding groove of the short-circuit welding plate and the sliding groove of the overload welding plate.

[0020] Furthermore, a fixing plate is provided on the inner side wall of the end cover and is located on a side of the overload step away from the short-circuit step, and the electromagnetic coil is fixed on the fixing plate.

[0021] Furthermore, the melting tube includes a tube body, and two baffles respectively fixed to both ends of the tube body;

[0022] The baffle is provided with an overload fuse installation hole and a short-circuit fuse installation hole, an overload fuse cover is provided at the overload fuse installation hole, and a short-circuit fuse cover is provided at the short-circuit fuse installation hole;

[0023] The overload welding plate is installed on the overload fuse cover plate, and the short-circuit welding plate is installed on the short-circuit fuse cover plate.

[0024] Furthermore, the overload fuse includes two overload fuse connection plates located inside the tube body and connected to the overload welding plate, a plurality of overload fuses distributed in parallel are arranged between the two overload fuse connection plates, and a plurality of tinning grooves are opened on the overload fuses;

[0025] The short-circuit fuse comprises two short-circuit fuse connection plates located inside the tube body and connected to the short-circuit welding plate, and a plurality of short-circuit fuses distributed in parallel are arranged between the two short-circuit fuse connection plates;

[0026] The melting tube is filled with quartz sand for covering the overload melt and the short-circuit melt.

[0027] Furthermore, the overload melt and the short-circuit melt are both provided with narrow portions;

[0028] When the overload current passes through the overload fuse, the narrow part of the overload fuse melts and generates an arc, and the quartz sand is heated by the arc and melts to extinguish the arc; the overload current is a current that is more than five times but less than the rated working current of the overload fuse;

[0029] When the short-circuit current passes through the short-circuit fuse, the narrow part of the short-circuit fuse melts and generates an arc, and the quartz sand is heated by the arc and melts to extinguish the arc; the short-circuit current is five times or more of the rated working current of the overload fuse.

[0030] Furthermore, a base is installed between the two overload fuse cover plates and between the two short-circuit fuse cover plates, and the base is provided with elastic indicator particles for indicating the blowing of the overload fuse and the short-circuit fuse.

[0031] Furthermore, the overload fuse cover plate and the short-circuit fuse cover plate are both provided with sand filling holes, and plugs are installed in the sand filling holes.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The full-range protection fuse provided by the present invention integrates a short-circuit fuse and an overload fuse in a fuse tube. When the connection terminal is connected to the rated working current and the overload current (a current five times or less than the rated working current), the overload fuse is connected to the circuit. When the connection terminal is connected to the short-circuit current (a current five times or more than the rated working current), the Ampere force generated by the electromagnetic coil pushes the push plate to separate from the overload step and contact with the short-circuit step, and the short-circuit fuse is connected to the circuit. The fuse can be suitable for disconnecting currents with different multiples of overload. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural schematic diagram of an embodiment of the present invention;

[0035] Figure 2 It is a perspective structural diagram of an embodiment of the present invention;

[0036] Figure 3 for Figure 2 A schematic diagram of the enlarged structure at point A in the middle.

[0037] Explanation of the accompanying drawings: 1 is a fuse tube, 11 is a tube body, 12 is an overload fuse cover plate, 13 is a short-circuit fuse cover plate, 2 is an end cover, 21 is a fixing plate, 3 is a connecting terminal, 4 is an overload fuse, 41 is an overload welding plate, 42 is an overload melt connecting plate, 43 is an overload melt, 44 is a tin-enameling tank, 5 is a short-circuit fuse, 51 is a short-circuit welding plate, 52 is a short-circuit melt connecting plate, 53 is a short-circuit melt, 6 is a switching mechanism, 61 is a push plate, 62 is a short-circuit step, 63 is an overload step, 64 is a convex bump, 7 is an electromagnetic coil, 8 is a slide groove, 9 is a narrow portion, 10 is a base, 14 is an elastic indicator particle, and 15 is a plug. DETAILED DESCRIPTION

[0038] The technical solutions in the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] like Figure 1 As shown, a full-range protection fuse is used in circuits with complex working conditions, where both low-multiple overload currents (overload currents) and large-interrupting fault short-circuit currents (short-circuit currents) may occur in the circuit; it includes a fuse tube 1, and both ends of the fuse tube 1 are provided with end caps 2 with connection terminals 3;

[0040] like Figure 2 As shown, an overload fuse 4 and a short-circuit fuse 5 are arranged in the melting tube 1, overload welding plates 41 are arranged at both ends of the overload fuse 4, and short-circuit welding plates 51 are arranged at both ends of the short-circuit fuse 5;

[0041] like Figure 2 and Figure 3 As shown, a switching mechanism 6 is slidably installed between the short-circuit welding plate 51 and the overload welding plate 41 located in the same end cover 2, and the switching mechanism 6 includes a push plate 61, and a short-circuit step 62 and an overload step 63 distributed on both sides of the push plate 61; the short-circuit step 62 is connected to the short-circuit welding plate 51, and the overload step 63 is connected to the overload welding plate 41;

[0042] like Figure 2 and Figure 3As shown, in the initial state, the push plate 61 is connected to the overload step 63; when the connection terminal 3 is connected to the rated working current of the overload fuse 4, and the overload current (a current greater than five times but less than the rated working current of the overload fuse 4) passes through the electromagnetic coil 7 and the push plate 61, the electromagnetic coil 7 generates a constant magnetic field, and generates an Ampere force (left-hand rule) on the energized push plate 61 in the direction of the overload fuse 43. At this time, the current is small, and the Ampere force is not enough to drive the push plate 61;

[0043] When the connecting terminal 3 is connected to a short-circuit current (a current five times or more than the rated working current of the overload fuse 4), the short-circuit current passes through the electromagnetic coil 7 and the push plate 61, the magnetic field strength generated by the electromagnetic coil 7 increases, and the Ampere force generated on the energized push plate 61 increases. The electromagnetic coil 7 can drive the push plate 61 to separate from the overload step 63 and connect to the short-circuit step 62 through the Ampere force, thereby switching the overload fuse 4 to the short-circuit fuse 5, and the short-circuit fuse 5 disconnects the short-circuit current.

[0044] like Figure 3 As shown, in order to achieve stable electrical connection between the push plate 61 and the short-circuit step 62 and the overload step 63, multiple convex bumps 64 are provided on both sides of the push plate 61; one side of the push plate 61 can be connected to the short-circuit step 62 through the multiple convex bumps 64, and the other side can be connected to the overload step 63 through the multiple convex bumps 64.

[0045] like Figure 2 and Figure 3 As shown, in order to enable the push plate 61 to slide between the short-circuit welding plate 51 and the overload welding plate 41, a slide groove 8 is provided on the side surfaces of the overload welding plate 41 and the short-circuit welding plate 51 located in the same end cover 2 that are close to each other; the short-circuit step 62 is installed in the slide groove 8 of the short-circuit welding plate 51, and the overload step 63 is installed in the slide groove 8 of the overload welding plate 41; the push plate 61 is slidably installed between the short-circuit welding plate 51 and the overload welding plate 41 through the slide groove 8 of the short-circuit welding plate 51 and the slide groove 8 of the overload welding plate 41. The slide groove 8 can limit the sliding direction of the push plate 61 between the short-circuit welding plate 51 and the overload welding plate 41.

[0046] like Figure 3 As shown, in order to achieve the installation and fixation of the electromagnetic coil 7 and enable the electromagnetic coil 7 to push the push plate 61 to slide in the slide groove 8 when a short-circuit current passes through, a fixing plate 21 is provided on the inner wall of the end cover 2 and is located on the side of the overload step 63 away from the short-circuit step 62, and the electromagnetic coil 7 is fixed on the fixing plate 21.

[0047] like Figure 2As shown, the fuse tube 1 includes a tube body 11 and two baffles respectively fixed at both ends of the tube body 11; the baffle is provided with an overload fuse 4 mounting hole and a short-circuit fuse 5 mounting hole, an overload fuse cover 12 is provided at the overload fuse 4 mounting hole, and a short-circuit fuse cover 13 is provided at the short-circuit fuse 5 mounting hole; the overload welding plate 41 is installed on the overload fuse cover 12, and the short-circuit welding plate 51 is installed on the short-circuit fuse cover 13.

[0048] like Figure 2 As shown, the overload fuse 4 includes two overload melt connecting plates 42 located inside the tube body 11 and connected to the overload welding plate 41, a plurality of parallel distributed overload melts 43 are arranged between the two overload melt connecting plates 42, and a plurality of tin-plating grooves 44 are opened on the overload melt 43; the tin-plating grooves 44 are opened on the overload melt 43 to facilitate adding tin into the tin-plating grooves 44, and the M effect point is used to reduce the melting point of the overload melt 43 at the tin-plating grooves 44, and after adding tin, the overload melt 43 is suitable for a current of more than five times but less than the rated working current of the overload fuse 4.

[0049] like Figure 2 As shown, the short-circuit fuse 5 includes two short-circuit fuse connecting plates 52 located inside the tube body 11 and connected to the short-circuit welding plate 51, and a plurality of parallel distributed short-circuit fuses 53 are arranged between the two short-circuit fuse connecting plates 52; the melting tube 1 is filled with quartz sand for covering the overload melt 43 and the short-circuit melt 53.

[0050] like Figure 2 As shown, in order to enable the overload fuse 43 and the short-circuit fuse 53 to melt within a specified time to achieve current interruption, a narrow portion 9 is provided on the overload fuse 43 and the short-circuit fuse 53; when the overload current passes through the overload fuse 43, the narrow portion 9 of the overload fuse 43 melts and generates an arc, and the quartz sand is heated by the arc and melts to extinguish the arc; when the short-circuit current passes through the short-circuit fuse 53, the narrow portion 9 of the short-circuit fuse 53 melts and generates an arc, and the quartz sand is heated by the arc and melts to extinguish the arc.

[0051] like Figure 1 and Figure 2 As shown, in order to visually observe whether the overload fuse 4 and the short-circuit fuse 5 are blown, a base 10 is installed between the two overload fuse cover plates 12 and between the two short-circuit fuse cover plates 13. The base 10 is provided with elastic indicator particles 14 for indicating the blowing of the overload fuse 4 and the short-circuit fuse 5.

[0052] like Figure 2 As shown, in order to facilitate the filling of quartz sand into the melting tube 2, the overload fuse cover plate 12 and the short-circuit fuse cover plate 13 are both provided with sand filling holes, and plugs 15 are installed in the sand filling holes to prevent the leakage of quartz sand.

[0053] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A full-range protection fuse, comprising a fuse tube (1), both ends of the fuse tube (1) being provided with end caps (2) with connection terminals (3); characterized in that: An overload fuse (4) and a short-circuit fuse (5) are arranged in the fusion tube (1); both ends of the overload fuse (4) are provided with overload welding plates (41); and both ends of the short-circuit fuse (5) are provided with short-circuit welding plates (51); A switching mechanism (6) is slidably installed between the short-circuit welding plate (51) and the overload welding plate (41) located in the same end cover (2); in an initial state, the switching mechanism (6) is connected to the overload welding plate (41); An electromagnetic coil (7) is provided in the end cover (2), one end of the electromagnetic coil (7) is connected to the wiring terminal, and the other end is connected to the switching mechanism (6); When the connection terminal (3) is connected to a short-circuit current, the short-circuit current passes through the electromagnetic coil (7) and the switching mechanism (6), and the electromagnetic coil (7) drives the switching mechanism (6) to separate from the overload welding plate (41) and connect to the short-circuit welding plate (51), so that the overload fuse (4) is switched to the short-circuit fuse (5), and the short-circuit fuse (5) disconnects the short-circuit current.

2. The full range protection fuse according to claim 1, characterized in that: The switching mechanism (6) comprises a push plate (61), and a short-circuit step (62) and an overload step (63) distributed on both sides of the push plate (61); the short-circuit step (62) is connected to the short-circuit welding plate (51), and the overload step (63) is connected to the overload welding plate (41); In the initial state, the push plate (61) is connected to the overload step (63); When the connection terminal (3) is connected to a short-circuit current, the short-circuit current passes through the electromagnetic coil (7) and the push plate (61), and the electromagnetic coil (7) drives the push plate (61) to separate from the overload step (63) and connect to the short-circuit step (62), so that the overload fuse (4) is switched to the short-circuit fuse (5), and the short-circuit fuse (5) disconnects the short-circuit current.

3. The full range protection fuse according to claim 2, characterized in that: Both sides of the push plate (61) are provided with a plurality of convex bumps (64); one side of the push plate (61) can be connected to the short-circuit step (62) through the plurality of convex bumps (64), and the other side can be connected to the overload step (63) through the plurality of convex bumps (64).

4. The full range protection fuse according to claim 2, characterized in that: A slide groove (8) is provided on the side surfaces of the overload welding plate (41) and the short-circuit welding plate (51) located in the same end cover (2) that are close to each other; the short-circuit step (62) is installed in the slide groove (8) of the short-circuit welding plate (51), and the overload step (63) is installed in the slide groove (8) of the overload welding plate (41); The push plate (61) is slidably installed between the short-circuit welding plate (51) and the overload welding plate (41) through the slide groove (8) of the short-circuit welding plate (51) and the slide groove (8) of the overload welding plate (41).

5. The full range protection fuse according to claim 2, characterized in that: A fixing plate (21) is provided on the inner side wall of the end cover (2) and is located on the side of the overload step (63) away from the short-circuit step (62), and the electromagnetic coil (7) is fixed on the fixing plate (21).

6. The full range protection fuse according to claim 1, characterized in that: The molten tube (1) comprises a tube body (11) and two baffles respectively fixed at two ends of the tube body (11); The baffle is provided with an overload fuse (4) mounting hole and a short-circuit fuse (5) mounting hole, an overload fuse cover (12) is provided at the overload fuse (4) mounting hole, and a short-circuit fuse cover (13) is provided at the short-circuit fuse (5) mounting hole; The overload welding plate (41) is mounted on the overload fuse cover plate (12), and the short-circuit welding plate (51) is mounted on the short-circuit fuse cover plate (13).

7. The full range protection fuse according to claim 5, characterized in that: The overload fuse (4) comprises two overload fuse connecting plates (42) located inside the tube body (11) and connected to the overload welding plate (41); a plurality of overload fuses (43) distributed in parallel are arranged between the two overload fuse connecting plates (42); and a plurality of tinning grooves (44) are arranged on the overload fuse (43); The short-circuit fuse (5) comprises two short-circuit fuse connection plates (52) located inside the tube body (11) and connected to the short-circuit welding plate (51), and a plurality of short-circuit fuses (53) distributed in parallel are arranged between the two short-circuit fuse connection plates (52); The melting tube (1) is filled with quartz sand for covering the overload melt (43) and the short-circuit melt (53).

8. The full range protection fuse according to claim 7, characterized in that: The overload fuse (43) and the short-circuit fuse (53) are both provided with a narrow portion (9); When the overload current passes through the overload fuse (43), the narrow portion (9) of the overload fuse (43) melts and generates an arc, and the quartz sand is heated by the arc and melts to extinguish the arc; the overload current is a current that is greater than or equal to five times but less than or equal to the rated working current of the overload fuse (4); When the short-circuit current passes through the short-circuit fuse (53), the narrow portion (9) of the short-circuit fuse (53) melts and generates an arc, and the quartz sand is heated by the arc and melts to extinguish the arc; the short-circuit current is a current five times or more of the rated working current of the overload fuse (4).

9. The full range protection fuse according to claim 5, characterized in that: A base (10) is installed between two overload fuse cover plates (12) and between two short-circuit fuse cover plates (13). The base (10) is provided with elastic indicating particles (14) for indicating the blowing of the overload fuse (4) and the short-circuit fuse (5).

10. The full range protection fuse according to claim 5 or 9, characterized in that: The overload fuse cover plate (12) and the short-circuit fuse cover plate (13) are both provided with sand filling holes, and plugs (15) are installed in the sand filling holes.

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