Backup protection surge protector
By connecting the main fuse and surge protector in series in the surge protector, and using the thermistor and current limiting resistor control circuits, the problem of poor impact resistance of traditional surge protectors is solved, and a higher impact resistance and lower failure rate.
Patent Information
- Application Number
- CN202323657115.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-31
- Publication Date
- 2025-01-14
- Estimated Expiration
- 2033-12-31
AI Technical Summary
In the case of industrial frequency current, the fuse has poor impact current resistance, resulting in the need to use models with a small rated current, which is prone to disconnect the circuit due to the impact current, and the thermal tripping component has a mechanical active structure. , the failure rate is high.
A backup protection surge protector is designed. By connecting the main fuse and the surge protector body in series in the main circuit, and setting the switch and current transformer in the control circuit, the thermistor and current limiting resistor are used to achieve The fuses with industrial frequency current are selected to use models with large rated currents, and avoid mechanical activities through the principle of hot melting and reduce the failure rate.
The fuse's impact current resistance is improved, the circuit breaker is avoided caused by impact current, and the failure rate is reduced. The thermal melting principle is adopted without mechanically active structure, which makes the failure rate is even lower.
Smart Images
Figure CN222355961U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of surge protector equipment, in particular to 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 realize the conduction and shunting of the impact current through the internal varistor, so as to avoid 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 fusing, thereby achieving the purpose of thermal tripping; when the varistor of the surge protector deteriorates to a certain extent and the power frequency current flowing through the surge protector is large, the thermal trip component of the surge protector cannot trip before being damaged by heat for the large power frequency current. Therefore, 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 avoiding the heat generated by the power frequency circuit causing the surge protector body to burn.
[0003] The defect of the above scheme is that the surge protector body is connected in series with the fuse. When the industrial frequency current flows through, the resistance of the varistor of the surge protector body is still large after deterioration to a certain extent, so the current flowing through the fuse is small. 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
[0004] On the one hand, the utility model provides a backup protection surge protector, which can improve the ability of the fuse to withstand impact current.
[0005] The backup protection surge protector provided by the utility model comprises a surge protector body, a main fuse, a main circuit and a control circuit; the surge protector body is arranged on the main circuit, the control circuit is arranged in parallel with the surge protector body to form a protection circuit, the main fuse is arranged in series with the protection circuit, and a switch is provided on the control circuit, and the switch can control the connection or disconnection of the control circuit according to the current size of the main circuit.
[0006] Furthermore, a current transformer is provided on the main circuit, the current transformer is connected in series with the protection circuit, the output end of the current transformer is electrically connected to the electromagnetic component, and the electromagnetic component can be linked with the switch component.
[0007] Furthermore, the main circuit includes an access terminal and a ground terminal connected to the power supply line, and along the direction from the access terminal to the ground terminal, the current transformer, the surge protector body and the main fuse are sequentially arranged in series on the main circuit.
[0008] Furthermore, a thermistor is provided on the control loop.
[0009] Furthermore, the control loop is also provided with a current limiting resistor, and the current limiting resistor is arranged between the thermistor and the main fuse.
[0010] Furthermore, the control circuit is also provided with a current limiting resistor and a thermistor, the main circuit includes an access terminal connected to the power supply line and a ground terminal, and along the direction from the access terminal to the ground terminal, the switch element, the thermistor and the current limiting resistor are sequentially arranged in series.
[0011] Furthermore, the main fuse includes a fuse and a heating element, the fuse is connected in series to the main circuit, one end of the heating element is connected to the control circuit, and the other end is grounded or connected to the grounded end of the fuse.
[0012] Furthermore, the backup protection surge protector also includes a control fuse, and the control fuse is arranged in series on the control loop.
[0013] Furthermore, the main circuit includes an access terminal and a ground terminal connected to the power supply line, and along the direction from the access terminal to the ground terminal, the control fuse and the switch element are sequentially arranged in series.
[0014] Furthermore, the fusing time of the control fuse is greater than the fusing time of the main fuse.
[0015] Beneficial Effects
[0016] The main fuse in this solution is set in series on the main circuit, and the surge protector body is also connected in series on the main circuit. The control circuit is connected in parallel with the surge protector body. A switch is provided on the control circuit. The switch can control the connection or disconnection of the control circuit according to the current size of the main circuit. When there is no current passing through, the switch remains in a normally open state. When there is power frequency current flowing through the main circuit, the switch is closed according to the preset trigger condition to connect the control circuit. At this time, most of the current bypasses the surge protector through the control circuit, so that the power frequency current flows through the main fuse. At this time, the current value of the power frequency current is large. Therefore, compared with the traditional solution, this solution can use a fuse with a larger rated current to avoid the impact current from disconnecting the circuit in the fuse. And compared with the traditional solution that uses a circuit breaker to implement a backup protection solution, the main fuse in this solution is a thermal melt principle, and there is no mechanical active structure, so its failure rate is low. 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 It is an overall schematic diagram provided by Embodiment 1 and Embodiment 2 of the present utility model;
[0019] Figure 2 It is a specific circuit diagram provided by Embodiment 1 and Embodiment 2 of the present utility model.
[0020] Figure numbers: 1-main circuit; 2-surge protector body; 3-surge protector body; 4-main fuse; 5-control circuit; 6-switch component; 7-electromagnetic component; 8-current transformer; 9-fuse component; 10-heating component; 11-control fuse. DETAILED DESCRIPTION
[0021] 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.
[0022] Embodiment 1
[0023] like Figure 1 and Figure 2As shown, the backup protection surge protector includes a surge protector body 2, a main fuse 4, a main circuit 1 and a control circuit 5; the surge protector body 2 is arranged on the main circuit 1, the control circuit 5 is arranged in parallel with the surge protector body 2 to form a protection circuit 3, the main fuse 4 is arranged in series with the protection circuit 3, and a switch 6 is provided on the control circuit 5, which can control the connection or disconnection of the control circuit 5 according to the current size of the main circuit 1.
[0024] The function of the surge protector body 2 is to protect the line it is connected to. The surge protector body 2 is used in electrical circuits or communication lines. Its principle is to realize the conduction and shunting of the impact current through the internal varistor, so as to avoid 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 2 used in the electrical circuit. When the varistor deteriorates and the surge protector body 2 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 2 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 avoiding the heat generated by the power frequency circuit causing the surge protector body 2 to burn. The defect of the above scheme is that the surge protector body 2 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 2. 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 2, 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 main fuse 4 in this scheme is arranged in series on the main circuit 1, and the surge protector body 2 is also connected in series on the main circuit 1. The control circuit 5 is connected in parallel with the surge protector body 2. The control circuit 5 is provided with a switch 6. The switch 6 can control the connection or disconnection of the control circuit 5 according to the current size of the main circuit 1. When no current passes through, the switch 6 remains in a normally open state. When the power frequency current flows through the main circuit 1, the switch 6 is closed according to the preset trigger condition to connect the control circuit 5. At this time, most of the current bypasses the surge protector through the control circuit 5, so that the power frequency current flows through the main fuse 4. At this time, the current value of the power frequency current is large, so a fuse with a larger rated current can be selected to avoid the impact current from disconnecting the circuit in the fuse.
[0025] The main circuit 1 adopts a main fuse 4 that can withstand a certain impact current. After the fuse core is disconnected in the middle, it is connected with a low-melting-point metal. The control circuit 5 adopts a metal wire with a certain impedance. After being disconnected in the middle, it is connected with the low-melting-point metal. The fuse core is coated with flux. When an overcurrent occurs in the main circuit 1, the switch 6 is actuated to switch to the control circuit 5. After the low-temperature metal is melted by the control circuit 5, it is easier to melt on the surface of the fuse core under the action of the flux, and finally the current of the main circuit 1 is disconnected.
[0026] Compared with the traditional solution of using circuit breakers to implement backup protection, the main fuse in this solution is based on the thermal melting principle and does not have a mechanically active structure, so its failure rate is lower.
[0027] In an optional embodiment, the main fuse 4 includes a fuse 9 and a heating element 10, the fuse 9 is connected in series to the main circuit 1, one end of the heating element 10 is connected to the control circuit 5, and the other end is grounded or connected to the grounded end of the fuse 9.
[0028] The fuse 9 can be melted at a certain temperature, thereby disconnecting the circuit. The fuse 9 in this solution is connected in series to the main circuit 1, preferably, connected in series to the main circuit 1 on the ground side of the surge protector body 2. The function of the heating element 10 is to generate heat under the action of current, thereby melting the fuse 9. The heating element 10 in this solution is connected in series to the control circuit 5. When an overcurrent occurs in the main circuit 1, the switch element 6 switches to the control circuit 5. Under the action of the overcurrent, the heating element generates heat and melts the fuse 9, thereby disconnecting the current of the main circuit 1. Preferably, one end of the heating element in this solution is connected to the control circuit 5 on the ground side of the switch element 6, and the other end is grounded.
[0029] In an optional embodiment, a current transformer 8 is provided on the main circuit 1 , and the current transformer 8 is arranged in series with the protection circuit 3 . The output end of the current transformer 8 is electrically connected to the electromagnetic component 7 , and the electromagnetic component 7 can be linked with the switch component 6 .
[0030] When a large overcurrent occurs in the main circuit 1, the output of the through-hole current transformer 8 drives the electromagnetic component 7 to operate, and the electromagnetic component 7 and the switch component 6 are linked to form an electromagnetic release. The switch component 6 is attracted under the action of the electromagnetic component 7, and the control circuit 5 is connected. The current of the main circuit 1 flows to the control circuit 5 through the contact between the control circuit 5 and the main circuit 1, and then flows to the main fuse 4 on the main circuit 1 through the contact on the other side, thereby avoiding the influence of the varistor in the surge protector body 2 on the rated current value of the main fuse 4.
[0031] In an optional embodiment, the main circuit 1 includes an access terminal and a ground terminal connected to the power line. Along the direction from the access terminal to the ground terminal, the current transformer 8, the surge protector body 2 and the main fuse 4 are sequentially arranged in series on the main circuit 1.
[0032] Alternatively, along the direction from the access end to the grounding end, the main fuse 4, the current transformer 8, and the surge protector body 2 are sequentially connected in series on the main circuit 1.
[0033] Alternatively, along the direction from the access end to the grounding end, the main fuse 4, the surge protector body 2 and the current transformer 8 are sequentially connected in series on the main circuit 1.
[0034] In an optional implementation, a thermistor is provided on the control loop 5 .
[0035] Preferably, the thermistor is an NTC thermistor.
[0036] In an optional implementation, a current limiting resistor is further provided on the control loop 5 , and the current limiting resistor is arranged between the thermistor and the main fuse 4 .
[0037] On the control loop 5, along the direction from the access end to the ground end, a thermistor and a current limiting resistor are arranged in sequence.
[0038] Embodiment 2
[0039] The backup protection surge protector further includes a control fuse 11 , which is connected in series with the switch element 6 on the control loop 5 .
[0040] Preferably, the fusing time of the control fuse 11 is greater than the fusing time of the main fuse 4 .
[0041] When power frequency current flows through the main circuit 1, the switch 6 is closed according to the preset trigger condition to connect the control circuit 5. At this time, most of the current bypasses the surge protector through the control circuit 5, so that the power frequency current flows through the main fuse 4. At this time, the current value of the power frequency current is relatively large, so a main fuse 4 with a larger rated current can be selected to avoid the impact current from disconnecting the circuit in the fuse.
[0042] When there is an impact current, the impact current passes through the main circuit 1. Since the impact current lasts for a very short time, there is a delay in the action execution time of the electromagnetic component 7 and the switch component 6, so the control circuit 5 remains in an open state.
[0043] The main circuit 1 adopts a main fuse 4 that can withstand a certain impact current, and the control fuse 11 of the control circuit 5 lags behind the main fuse 4 in the melting. After the fuse 9 of the main fuse 4 melts, since the control circuit 5 can still remain connected, the power cable can be grounded through the heating element 10 on the control circuit 5, so at this time the power frequency current flows to the ground through the heating element 10 on the control circuit 5, so the control fuse 11 in this scheme melts after the main fuse 4 melts, thereby preventing the control circuit 5 from continuing to flow current. The fuse core of the main fuse 4 is connected by a low melting point metal after being disconnected in the middle, and the control circuit 5 uses a metal wire with a certain impedance, which is connected to the low melting point metal after being disconnected in the middle as shown in the figure. The fuse core is coated with flux. When the main circuit 1 has an overcurrent, the switch 6 is switched to the control circuit 5. After the low-temperature metal is melted by the control circuit 5, it is easier to melt on the surface of the fuse core under the action of the flux, and finally the current of the main circuit 1 is disconnected. After the main fuse 4 is blown, the control fuse 11 is blown.
[0044] In an optional embodiment, a current limiting resistor and a thermistor are also provided on the control circuit 5, and the main circuit 1 includes an access terminal and a ground terminal connected to the power supply line. Along the direction from the access terminal to the ground terminal, the control fuse 11, the switch element 6, the thermistor and the current limiting resistor are arranged in series in sequence.
[0045] Embodiment 3
[0046] The backup protection surge protector also includes a shell, two cavities are provided in the shell, two openings corresponding to the two cavities are provided on the shell, a first contact is provided at the bottom of each cavity, and a second contact is provided near the opening of each cavity. The main fuse and the control fuse both have a first contact end and a second contact end. When the main fuse or the control fuse is placed in one of the cavities, the first contact cooperates with the first contact end, and the second contact cooperates with the second contact end.
[0047] The main fuse and the control fuse are respectively matched with the corresponding cavities to realize quick disassembly. When a power frequency current passes through, the main fuse and the control fuse are blown. When replacing the main fuse and the control fuse, the damaged main fuse and the control fuse are taken out from the cavity through the opening, and the replaced main fuse and the control fuse are placed in the cavity through the opening. The first contact piece cooperates with the first contact end, and the second contact piece cooperates with the second contact end, so that the main fuse is connected in series to the main circuit, and the control fuse is connected in series to the control circuit. When the main fuse and the control fuse are placed in the cavity, the main fuse and the control fuse can both contact with the first contact piece and the second contact piece corresponding to each other, thereby realizing electrical connection.
[0048] In an optional embodiment, the first contact piece has an abutment surface facing the opening, and one end of the second contact piece forms a pipe structure with a threaded outer wall. The pipe structure extends out of the cavity through the opening, and the pipe structure can engage with the inner annular surface of the cover body. When the main fuse or the control fuse is placed into the cavity through the inner cavity of the pipe structure, the inner end surface of the cover body abuts against the second contact end.
[0049] The first contact end and the second contact end of the main fuse and the control fuse are respectively located at the two ends of their cylinders. When placed in the cavity, the end where the first contact end is located is pushed into the cavity from the front opening. When the first contact end is pushed to contact the abutting surface of the first contact piece, the cover body and the pipeline structure of the second contact piece are tightened and engaged. During the tightening process of the cover body, the inner end surface of the cover body contacts the end where the second contact end is located. The outside of the cover body is insulating material, and the inner end surface and inner ring surface inside are integrally formed of conductive material. The second contact end forms an electrical connection with the pipeline structure through the inner end surface and inner ring surface of the cover body, thereby electrically connecting the second contact end to the second contact piece.
[0050] The end of the second contact piece is processed to form a pipe structure, which extends out of the cavity through the opening. The outer ring surface of the pipe structure is embedded with the inner wall of the opening, so that the pipe structure is fixed in the opening. The outer ring surface of the pipe structure outside the opening is processed to form a thread to facilitate engagement with the cover body. Both sides of the inner cavity of the pipe structure are connected, and the main fuse and the control fuse can enter the cavity from the outside through the pipe structure.
[0051] In an optional implementation, the first contact piece has an elastic section, the elastic section can be deformed under the action of the first contact end, and the abutting surface is located on the elastic section.
[0052] 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.
[0053] 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 backup protection surge protector, characterized in that: The invention comprises a surge protector body (2), a main fuse (4), a main circuit (1) and a control circuit (5); the surge protector body (2) is arranged on the main circuit (1); the control circuit (5) and the surge protector body (2) are arranged in parallel to form a protection circuit (3); the main fuse (4) and the protection circuit (3) are arranged in series; a switch (6) is provided on the control circuit (5); the switch (6) can control the connection or disconnection of the control circuit (5) according to the current size of the main circuit (1); The main circuit (1) is provided with a current transformer (8), the current transformer (8) is arranged in series with the protection circuit (3), the output end of the current transformer (8) is electrically connected to the electromagnetic component (7), and the electromagnetic component (7) can be linked with the switch component (6); The main circuit (1) comprises an access terminal connected to a power supply line and a ground terminal, and in a direction from the access terminal to the ground terminal, the current transformer (8), the surge protector body (2) and the main fuse (4) are sequentially arranged in series on the main circuit (1); The control circuit (5) is provided with a thermistor.
2. The backup protection surge protector according to claim 1, characterized in that: The control circuit (5) is also provided with a current limiting resistor, which is arranged between the thermistor and the main fuse (4).
3. The backup protection surge protector according to claim 1, characterized in that: The control circuit (5) is also provided with a current limiting resistor and a thermistor. The main circuit (1) comprises an access terminal connected to a power supply line and a ground terminal. Along the direction from the access terminal to the ground terminal, the switch element (6), the thermistor and the current limiting resistor are sequentially connected in series.
4. The backup protection surge protector according to claim 1, characterized in that: The main fuse (4) comprises a fuse element (9) and a heating element (10), wherein the fuse element (9) is connected in series to the main circuit (1), and one end of the heating element (10) is connected to the control circuit (5), and the other end is grounded or connected to the grounded end of the fuse element (9).
5. The backup protection surge protector according to claim 4, characterized in that: The backup protection surge protector further comprises a control fuse (11), and the control fuse (11) is arranged in series on the control circuit (5).
6. The backup protection surge protector according to claim 5, characterized in that: The main circuit (1) comprises an access terminal connected to a power supply line and a ground terminal, and along the direction from the access terminal to the ground terminal, the control fuse (11) and the switch element (6) are sequentially arranged in series.
7. The backup protection surge protector according to claim 6, characterized in that: The fusing time of the control fuse (11) is greater than the fusing time of the main fuse (4).