Fuse and backup protection surge protector

Abstract

The utility model relates to the field of surge protector equipment, in particular to a fuse and a backup protection surge protector. The fuse provided by the utility model is used for backup protection of a surge protector body and comprises a fusing piece and a heating piece, the fusing piece is used for being connected with the surge protector body in series, the heating piece is matched with the fusing piece, and the heating piece is used for heating the surge protector body when power frequency current passes through a lightning protection circuit where the surge protector body is located. And the fuse element is fused by electrifying and generating heat, so that the lightning protection circuit is disconnected. The impact current resistance of the fuse can be improved.

Description

Technical Field

[0001] The utility model relates to the field of surge protector equipment, in particular to a fuse and a backup protection surge protector. Background Art

[0002] The function of the surge protector body is to protect the line it is connected to. The surge protector body is used in electrical circuits or communication lines. Its principle is to conduct and shunt the impact current through the internal varistor, thereby preventing the impact current from damaging the equipment on the electrical circuit or communication line. The varistor may deteriorate after long-term use. In the traditional solution, a thermal trip component is provided in the surge protector body used in the electrical circuit. When the varistor deteriorates and the surge protector body is subjected to a continuous small current impact, the thermal trip component can disconnect the connection between the line and the ground wire by melting, thereby achieving the purpose of thermal tripping; and for the power frequency current, the surge protector body is protected by connecting it in series with the fuse. Specifically, when the power frequency current flows through the fuse, the circuit in the fuse is disconnected, thereby preventing the heat generated by the power frequency circuit from causing the surge protector body to burn. The defect of the above scheme is that the surge protector body is connected in series with the fuse. When the power frequency current flows through it, the current flowing through the fuse is small due to the large resistance of the varistor of the surge protector body. In order to make the fuse blow, a model with a smaller rated current is required. When the impact current flows through the surge protector body, it will inevitably flow through the fuse, which may cause the circuit in the fuse with a smaller rated current to be disconnected. Therefore, the fuse in the above scheme has poor impact current resistance. Utility Model Content

[0003] On the one hand, the utility model provides a fuse that can improve the ability of the fuse to withstand impact current;

[0004] On the other hand, the utility model provides a backup protection surge protector.

[0005] The fuse provided by the utility model is used for backup protection of a surge protector body, and comprises a fuse and a heating element. The fuse is used to be connected in series with the surge protector body, and the heating element cooperates with the fuse. When the lightning protection circuit where the surge protector body is located passes through the industrial frequency current, the heating element is energized to generate heat to melt the fuse, so that the lightning protection circuit is disconnected.

[0006] Furthermore, the fuse element includes a fuse part, and the heating element includes an electrode end, the electrode end cooperates with the fuse part, and the electrode end is used to generate an electric arc to melt the fuse part.

[0007] Furthermore, the fuse includes a fusible wire for forming the fuse element, and also includes an ignition electrode for forming the heating element, the fusible wire has a first connection end and a second connection end respectively connected to the lightning protection circuit, the fusible wire located between the first connection end and the second connection end is provided with the fusible part, the ignition electrode has an electrode end, and the electrode end is gap-fitted with the fusible part.

[0008] Furthermore, a gasket is provided between the electrode end and the fuse part, a through hole is provided on the gasket, and the electrode end and the fuse part are respectively located at two end openings of the through hole.

[0009] Furthermore, the fuse also includes a clamp, and the clamp has a first clamping portion and a second clamping portion, the first clamping portion cooperates with the ignition electrode, and the second clamping portion cooperates with the fuse.

[0010] Furthermore, the lightning protection circuit can be electrically connected to the ignition electrode through the first clamping portion, and an insulating block is provided between the second clamping portion and the fuse.

[0011] Furthermore, the clamp includes a first sheet, a second sheet and a third sheet, the first sheet is connected to the second sheet, there is a first gap between the first sheet and the second sheet for forming the first clamping part, the second sheet is connected to the third sheet, there is a second gap between the second sheet and the third sheet for forming the second clamping part.

[0012] Furthermore, the clamp includes a conductive plate, and the first sheet, the second sheet and the third sheet are formed by bending the plate.

[0013] Furthermore, the fuse also includes a tube body and two fuse caps. The tube body is provided with a cavity with openings at both ends. The two fuse caps are respectively arranged at the two openings and are sleeved with the tube body. The fuse element and the heating element are both located in the cavity.

[0014] The backup protection surge protector provided by the utility model comprises the fuse as described in any one of the above items.

[0015] Beneficial Effects

[0016] The fuse in this solution is connected in series with the lightning protection circuit where the surge protector body is located, and the heating element can draw power from the lightning protection circuit. When the power frequency current flows through the lightning protection circuit where the surge protector body is located, the heating element generates heat and melts the fuse. Compared with the traditional solution in which the surge protector body is connected in series with the fuse, when the power frequency current flows through, the current flowing through the fuse is small due to the large resistance of the varistor of the surge protector body. To make the fuse melt, a model with a smaller rated current is required. When the impact current flows through the surge protector body, it will inevitably flow through the fuse, which may cause the circuit in the fuse with a smaller rated current to be disconnected. Therefore, the fuse has poor impact current resistance. In this solution, only the fuse is connected in series with the circuit where the surge protector body is located. The heating element can be made of a material with a higher heating temperature under the same current conditions. Since the heating element can provide a higher melting temperature, a fuse with a higher rated temperature can be selected, thereby avoiding the impact current from disconnecting the circuit in the fuse, and improving the impact current resistance of the fuse. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is an overall schematic diagram of the fuse provided in the first embodiment of the utility model;

[0019] Figure 2 It is a structural schematic diagram of the clamp provided in the first embodiment of the utility model;

[0020] Figure 3 It is a cross-sectional schematic diagram provided by Embodiment 1 of the present utility model.

[0021] Figure numbers: 1-heating element; 2-fuse element; 3-clamp; 4-insulating block; 5-first clamping part; 6-second clamping part; 7-first sheet; 8-second sheet; 9-third sheet; 10-first gap; 11-second gap; 12-gasket; 13-fuse part; 14-electrode end; 15-first connecting end; 16-second connecting end. DETAILED DESCRIPTION

[0022] The specific implementation of the present invention is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described here is only used to illustrate and explain the present invention, and is not used to limit the present invention.

[0023] Embodiment 1

[0024] like Figures 1 to 3 A fuse is shown, which is used for backup protection of a surge protector body, and includes a fuse 2 and a heater 1. The fuse 2 is used to be connected in series with the surge protector body, and the heater 1 cooperates with the fuse 2. When the lightning protection circuit where the surge protector body is located passes the industrial frequency current, the heater 1 is powered on to generate heat to melt the fuse 2, so that the lightning protection circuit is disconnected.

[0025] The function of the surge protector body is to protect the line it is connected to. The surge protector body is used in power supply circuits or communication lines. Its principle is to realize the conduction and shunting of the impact current through the internal varistor, thereby preventing the impact current from damaging the equipment on the power supply circuit or communication line. The varistor may deteriorate after long-term use. In the traditional solution, a thermal trip component is provided in the surge protector body used in the power supply circuit. When the varistor deteriorates and the surge protector body is subjected to a continuous small current impact, the thermal trip component can disconnect the connection between the line and the ground wire by fusing, thereby achieving the purpose of thermal tripping; and for the power frequency current, the surge protector body is protected by connecting it in series with the fuse. Specifically, when the power frequency current flows through the fuse, the circuit in the fuse is disconnected, thereby preventing the heat generated by the power frequency circuit from causing the surge protector body to burn. The defect of the above scheme is that the surge protector body is connected in series with the fuse. When the power frequency current flows through it, the current flowing through the fuse is small due to the large resistance of the varistor of the surge protector body. In order to make the fuse blow, a model with a smaller rated current is required. When the impact current flows through the surge protector body, it will inevitably flow through the fuse, which may cause the circuit in the fuse with a smaller rated current to be disconnected. Therefore, the fuse in the above scheme has poor impact current resistance. Compared with the above scheme, the fuse 2 in this scheme is arranged in series on the lightning protection circuit where the surge protector body is located, and the heating element 1 can draw power from the lightning protection circuit. When the power frequency current flows through the lightning protection circuit where the surge protector body is located, the heating element 1 generates heat and melts the fuse 2. Compared with the traditional scheme, the power frequency current directly flows to the fuse through the surge protector body, and the fuse wire in the fuse melts due to self-heating. In the fuse of this scheme, only the fuse 2 is connected in series on the circuit where the surge protector body is located. The heating element 1 can be made of a material with a higher heating temperature under the same current conditions. Since the heating element 1 can provide a higher melting temperature, a fuse 2 with a higher rated temperature can be selected to avoid the impact current from disconnecting the circuit in the fuse.

[0026] In an optional embodiment, the fuse 2 includes a fuse portion 13 , and the heating element 1 includes an electrode terminal 14 , the electrode terminal 14 cooperates with the fuse portion 13 , and the electrode terminal 14 is used to generate an arc to melt the fuse portion 13 .

[0027] The first connection end 15 and the second connection end 16 of the fuse 2 are respectively connected to the lightning protection circuit, and the fuse part 13 is located between the first connection end 15 and the second connection end 16. When the fuse part 13 blows, the part between the first connection end 15 and the second connection end 16 of the fuse 2 can be disconnected, so that the lightning protection circuit is disconnected.

[0028] The electrode end 14 of the heating element 1 generates an arc, and the arc acts on the fuse portion 13 to disconnect the fuse element 2.

[0029] Alternatively, the heating element 1 includes an electric heating wire, which cooperates with the fuse part 13 , and the electric heating wire generates heat when it is energized to fuse the fuse part 13 .

[0030] In an optional embodiment, the fuse includes a fusible wire for forming a fuse element 2, and also includes an ignition electrode for forming a heating element 1, the fusible wire has a first connection end 15 and a second connection end 16 respectively connected to the lightning protection circuit, a fusible part 13 is provided on the fusible wire between the first connection end 15 and the second connection end 16, and the ignition electrode has an electrode end 14, and a gap is fitted between the electrode end 14 and the fusible part 13.

[0031] The ignition electrode in the traditional scheme includes a first electrode and a second electrode, and the ends of the first electrode and the second electrode are respectively located on both sides of the fuse. When the control circuit where the first electrode and the second electrode are located is energized, an arc appears in the gap between the first electrode and the second electrode, and the arc melts the fuse. Since the fuse is located between the first electrode and the second electrode, the gap between the first electrode and the second electrode is wide, resulting in a larger overall size of the fuse. An arc is formed between the ignition electrode and the fuse in this scheme, and specifically, an arc is formed between the electrode end 14 of the ignition electrode and the fusible part 13 of the fuse. The ignition electrode and the fuse can be made of materials with different rated temperatures or different sizes, so that the ignition electrode is less affected by the arc than the fuse, and the fuse is melted under the action of the arc. Compared with the traditional scheme, the ignition electrode and the fuse itself in this scheme constitute the two ends of the arc, so the gap forming the arc is smaller than the gap in the traditional scheme, and the overall size of the fuse is reduced.

[0032] The gap between the electrode end 14 and the fuse part 13 is about 0.1 mm to maintain the arc. The fuse part 13 is a portion of the fuse with a smaller thickness, so as to facilitate arc melting, or the rated temperature of the material at the fuse part 13 is lower than the rated temperature of the material at other positions of the fuse, so that the fuse part 13 melts and the first connection end 15 and the second connection end 16 of the fuse are broken.

[0033] In an optional embodiment, a gasket 12 is provided between the electrode terminal 14 and the fuse part 13, a through hole is provided on the gasket 12, and the electrode terminal 14 and the fuse part 13 are respectively located at two end openings of the through hole.

[0034] The gasket 12 is made of polytetrafluoroethylene, and its function is to insulate and ensure the gap distance between the electrode end 14 and the fuse part 13. Preferably, the fuse is a thin sheet structure, one side of the gasket 12 is in contact with the fuse, the electrode end 14 of the ignition electrode is a plane, and the plane is in contact with the other side of the gasket 12, at least a part of the plane of the electrode end 14 of the ignition electrode is located in the opening area of ​​the through hole close to the ignition electrode, at least a part of the fuse part 13 is located in the opening area of ​​the through hole close to the fuse, and the arc between the electrode end 14 and the fuse part 13 is generated in the through hole.

[0035] In an optional embodiment, the fuse further comprises a clamp 3, the clamp 3 comprises a first clamping portion 5 and a second clamping portion 6, the first clamping portion 5 cooperates with the ignition electrode, and the second clamping portion 6 cooperates with the fuse.

[0036] The function of the clamp 3 is to keep the relative position between the ignition electrode and the fuse fixed, wherein the first clamp 3 and the ignition electrode are detachably matched, the second clamp 3 and the fuse are detachably matched, and the position between the first clamp 3 and the second clamp 3 is relatively fixed.

[0037] Preferably, the first clamp 3 cooperates with the second clamp 3 so that the ignition electrode and the fuse are squeezed against each other, and a gasket 12 is provided between the ignition electrode and the fuse to maintain the gap size between the ignition electrode and the fuse.

[0038] Preferably, the first clamp 3 cooperates with the second clamp 3 so that the ignition electrode and the fuse wire maintain a relative position, there is no gasket 12 between the ignition electrode and the fuse wire, and the gap between the ignition electrode and the fuse wire is realized by the first clamp 3 and the second clamp 3, so that an arc can be generated and maintained between the ignition electrode and the fuse wire.

[0039] In an optional implementation, the lightning protection circuit can be electrically connected to the ignition electrode through the first clamping portion 5, and an insulating block 4 is provided between the second clamping portion 6 and the fuse.

[0040] The first clamping part 5 is made of conductive material, preferably, the first clamping part 5 is a copper alloy part, the current of the lightning protection circuit can pass through the first clamping part 5 to the ignition electrode, the fuse is connected in series to the lightning protection circuit, and an arc is generated between the fusing part 13 of the fuse and the ignition electrode under voltage.

[0041] Preferably, the second clamping portion 6 is insulated from the first clamping portion 5 , or the second clamping portion 6 is made of insulating material, so as to avoid a short circuit between the ignition electrode and the fuse through the clamp 3 .

[0042] Preferably, the second clamping portion 6 is formed integrally with the first clamping portion 5, that is, the second clamping portion 6 is also made of conductive material. In order to avoid a short circuit between the ignition electrode and the fuse through the clamp 3, the second clamping portion 6 and the fuse are insulated. Specifically, the insulating block 4 is made of ceramic material, and the insulating block 4 is located between the second clamping portion 6 and the fuse.

[0043] In an optional embodiment, the clamp 3 includes a first sheet 7, a second sheet 8 and a third sheet 9, the first sheet 7 and the second sheet 8 are connected, and there is a first gap 10 between the first sheet 7 and the second sheet 8 for forming a first clamping portion 5, the second sheet 8 and the third sheet 9 are connected, and there is a second gap 11 between the second sheet 8 and the third sheet 9 for forming a second clamping portion 6.

[0044] The second sheet 8 is U-shaped, one end of the first sheet 7 is connected to the bottom of the U-shaped groove, and the other end is bent to form a first gap 10 between the first sheet 7 and the second sheet 8, and the end thereof is parallel to the second sheet 8. The ignition electrode is a bolt-shaped carbon electrode, the head of which is embedded in the first gap 10, the rod passes through the U-shaped groove, and the end of the rod forms an electrode end 14, which extends into the second gap 11 between the second sheet 8 and the third sheet 9. One end of the third sheet 9 is connected to the second sheet 8, and the other end is bent in the direction opposite to the bending direction of the first sheet 7 to form a C shape, and the end thereof is parallel to the second sheet 8. There are two third sheets 9, which are respectively arranged on both sides of the groove of the second sheet 8 and symmetrically arranged. A second gap 11 is formed between the ends of the two third sheets 9 and the second sheet 8. The fuse is located in the second gap 11. There are insulating blocks 4 on one side of the fuse close to the second sheet 8 and on the other side close to the end of the third sheet 9. The two insulating blocks 4 clamp the fuse and the gasket 12 to avoid direct contact between the fuse and the second sheet 8 and the third sheet 9.

[0045] In an optional implementation, the clamp 3 includes a conductive plate, and the first sheet 7, the second sheet 8 and the third sheet 9 are formed by bending the plate.

[0046] In an optional embodiment, the fuse also includes a tube body and two fuse caps. The tube body is provided with a cavity with openings at both ends. The two fuse caps are respectively arranged at the two openings and are sleeved with the tube body. The fuse 2 and the heating element 1 are both located in the cavity.

[0047] Embodiment 2

[0048] The backup protection surge protector provided by the utility model comprises any fuse as described above.

[0049] In an optional implementation, the surge protector further includes a surge protector body and a control circuit. The surge protector body and the fuse are connected in series to the lightning protection circuit. The ignition electrode is arranged on the control circuit. The control circuit can draw power from the lightning protection circuit.

[0050] The fuse in this solution is arranged in series on the lightning protection circuit, and the surge protector body is also connected in series on the lightning protection circuit. An electrical component is provided on the control circuit, and the electrical component can control whether the control circuit is energized according to the current electrical parameters of the lightning protection circuit. When the industrial frequency current flows through the lightning protection circuit, the electrical component energizes the control circuit according to preset conditions. The source of its electrical energy is the lightning protection circuit. After the control circuit is energized, the ignition electrode transfers heat to the fuse through an electric arc.

[0051] In an optional embodiment, a current transformer is provided on the lightning protection circuit, and the current transformer includes a primary side and a secondary side. The primary side is connected in series to the lightning protection circuit, and the secondary side is connected in series to the tripping circuit. An electromagnetic release is provided on the tripping circuit, and the switch element of the electromagnetic release is arranged on the control circuit. The power supply end of the control circuit is connected to the lightning protection circuit.

[0052] When a large overcurrent appears on the lightning protection circuit where the surge protector body is located, the secondary side of the current transformer outputs current on the tripping circuit, causing the electromagnetic tripper to execute the action of closing the switch, and the ignition electrode on the control circuit is electrically connected to the lightning protection circuit, and a voltage is generated between the ignition electrode and the fuse. When the voltage exceeds the threshold, an arc is generated between the electrode end 14 of the ignition electrode and the fuse part 13 on the fuse. The arc heats the fuse part 13 to melt it, and then blows the fuse. Since the fuse is connected in series to the lightning protection circuit, the lightning protection circuit is disconnected. At this time, the power frequency current on the lightning protection circuit is disconnected, and the secondary side of the current transformer does not generate current, and the arc between the electrode end 14 of the ignition electrode and the fuse part 13 on the fuse disappears.

[0053] It should be noted that any of the above embodiments is illustrative of the present invention rather than limiting the present invention, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets should not be constructed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present invention may be implemented by means of hardware comprising several different elements and by means of appropriately programmed computers. In a unit claim that lists several devices, several of these devices may be embodied by the same hardware item. The use of the words primary, secondary, previous, and next, etc. does not indicate any order. These words may be interpreted as names.

[0054] The above implementation modes are only suitable for illustrating the present invention, but not for limiting the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The scope of patent protection of the present invention should be limited by the claims.

Claims

1. A fuse for backup protection of a surge protector body, characterized in that: The invention comprises a fuse (2) and a heating element (1), wherein the fuse (2) is connected in series with a surge protector body, and the heating element (1) cooperates with the fuse (2). When a power frequency current passes through a lightning protection circuit where the surge protector body is located, the heating element (1) is energized to generate heat to melt the fuse (2), thereby disconnecting the lightning protection circuit.

2. The fuse according to claim 1, characterized in that: The fuse (2) comprises a fuse part (13), and the heating element (1) comprises an electrode end (14), wherein the electrode end (14) cooperates with the fuse part (13), and the electrode end (14) is used to generate an electric arc to melt the fuse part (13).

3. The fuse according to claim 2, characterized in that: The fuse comprises a fusible wire for forming the fusible element (2), and also comprises an ignition electrode for forming the heating element (1), the fusible wire having a first connection end (15) and a second connection end (16) respectively connected to the lightning protection circuit, the fusible part (13) being provided on the fusible wire between the first connection end (15) and the second connection end (16), the ignition electrode forming the electrode end (14) at one end close to the fusible wire, and the electrode end (14) and the fusible part (13) being gap-fitted.

4. The fuse according to claim 3, characterized in that: A gasket (12) is provided between the electrode end (14) and the fuse part (13), a through hole is provided on the gasket (12), and the electrode end (14) and the fuse part (13) are respectively located at the openings at both ends of the through hole.

5. The fuse according to claim 3, characterized in that: The fuse also comprises a clamp (3), wherein the clamp (3) comprises a first clamping portion (5) and a second clamping portion (6), wherein the first clamping portion (5) cooperates with the ignition electrode, and the second clamping portion (6) cooperates with the fuse.

6. The fuse according to claim 5, characterized in that: The lightning protection circuit can be electrically connected to the ignition electrode via the first clamping portion (5), and an insulating block (4) is provided between the second clamping portion (6) and the fuse.

7. The fuse according to claim 6, characterized in that: The clamp (3) comprises a first sheet (7), a second sheet (8) and a third sheet (9); the first sheet (7) and the second sheet (8) are connected, and a first gap (10) for forming the first clamping portion (5) exists between the first sheet (7) and the second sheet (8); the second sheet (8) and the third sheet (9) are connected, and a second gap (11) for forming the second clamping portion (6) exists between the second sheet (8) and the third sheet (9).

8. The fuse according to claim 7, characterized in that: The clamp (3) comprises a conductive plate, and the first sheet (7), the second sheet (8) and the third sheet (9) are formed by bending the plate.

9. The fuse according to any one of claims 1 to 8, characterized in that: The fuse also includes a tube body and two fusible core caps. The tube body is provided with a cavity with openings at both ends. The two fusible core caps are respectively arranged at the two openings and are sleeved with the tube body. The fusible element (2) and the heating element (1) are both located in the cavity.

10. A backup protection surge protector, characterized in that: Comprising the fuse as described in any one of claims 1-9.

Images