Active and passive integrated protection intelligent fuse with single excitation source

Abstract

The invention provides an active and passive integrated protection intelligent fuse with a single excitation source. The active and passive integrated protection intelligent fuse comprises a first conducting bar, a signal melt, a second conducting bar, a circuit board and an excitation source, the circuit board is provided with the relay and the excitation source. The relay is connected with an external control unit, the excitation source, the first conducting bar and the second conducting bar. The first conducting bar, the signal melt and the second conducting bar are connected in sequence; an isolating layer is arranged on the relay, and the isolating layer is used for shielding crosstalk of external voltage on the relay; after a plurality of pins of the relay are welded on the circuit board, an insulation processing mode is adopted among the plurality of pins; and in an inspection working condition, the external control unit outputs a first inspection signal to the relay so as to control the relay to be switched into an inspection state, and feeds back the working state of the excitation source to the external control unit.

Description

Technical Field

[0001] This application belongs to the technical field of emergency protection devices, specifically relating to a single-excitation-source active-passive integrated protection intelligent fuse. Background Technology

[0002] The integrated active and passive protection intelligent fuse is a safety protection device used in the main circuit of high-voltage systems. With the increasing market demands for intelligence and safety in electric vehicles, it is gradually replacing traditional thermal fuses as the mainstream choice. Combining active and passive protection functions, it can more reliably cut off the circuit under different circumstances, ensuring the safety of people and the vehicle.

[0003] Current integrated active and passive protection functions are implemented through a built-in PCBA, on which external and internal trigger circuits are designed to implement active and passive protection functions, respectively. When an abnormal external current causes the fusible element of this type of smart fuse to melt, an extremely high arc voltage is generated. If this high-voltage signal cannot be effectively isolated from the external trigger circuit, it will cause a serious safety accident. This leads to a contradiction: When the external triggering circuit and the internal triggering circuit share the same excitation source, the internal triggering circuit often needs to use a transformer to collect the triggering signal, but this may cause it to be falsely triggered or fail to trigger properly due to strong radiation interference. When the external trigger circuit and the internal trigger circuit use different excitation sources, the working state of the excitation source corresponding to the internal trigger circuit cannot be detected, and sufficient insulation distance needs to be maintained between the two excitation sources to prevent the risk of high voltage generated during internal triggering from entering the external trigger circuit, but this will make the product very large. Summary of the Invention

[0004] This application provides a single-excitation-source integrated active and passive protection smart fuse, which aims to enhance the radiation immunity and high and low voltage insulation design of the smart fuse, thereby enabling the single-excitation-source smart fuse to simultaneously adapt to external triggering and internal triggering functions.

[0005] In one aspect, this application provides a single-excitation-source active-passive integrated protection smart fuse, including a first conductive bus, a signal fuse element, a second conductive bus, a circuit board, and an excitation source; The circuit board is provided with the relay and the excitation source. The relay is connected to the external control unit, the excitation source, the first busbar and the second busbar respectively. The first busbar, the signal fuse and the second busbar are connected in sequence. The relay is provided with an isolation layer, which is used to shield the relay from crosstalk caused by external voltage. After the multiple pins of the relay are soldered onto the circuit board, the multiple pins are insulated from each other. During the inspection process, the external control unit outputs a first inspection signal to the relay to control the relay to switch to the inspection state and to provide feedback on the status of the excitation source to the external control unit.

[0006] In conjunction with the first aspect, in one possible embodiment, the single-excitation-source active-passive integrated protection smart fuse further includes a first wire and a second wire; a first through hole is formed on the first conductive bus or the second conductive bus, and a second through hole is formed on the circuit board; one end of the first wire is soldered to the first conductive bus, and one end of the second wire is soldered to the second conductive bus; after one end of the first wire is soldered to the first conductive bus and one end of the second wire is soldered to the second conductive bus, the first wire and the second wire are twisted together and then pass through the first through hole and the second through hole in sequence, and the other end of the first wire and the other end of the second wire are respectively connected to the relay through the circuit board.

[0007] In conjunction with the first aspect, in one possible embodiment, when in an externally triggered state, the external control unit first outputs a second inspection signal to the relay to control the relay to switch to an externally triggered state; then it outputs a trigger voltage to the relay, and when the trigger current corresponding to the trigger voltage is greater than a first current threshold and the duration of the trigger current is greater than a preset time, the relay drives the excitation source to trigger.

[0008] In conjunction with the first aspect, in one possible embodiment, it further includes a first current limiting unit and a second current limiting unit; the first current limiting unit is used to limit the first inspection current or the second inspection current corresponding to the first inspection signal to less than a second current threshold when the first inspection current corresponding to the first inspection signal or the second inspection current corresponding to the second inspection signal flows through the excitation source; the second current limiting unit is used to limit the current flowing through the excitation source in the main circuit to less than the second current threshold when in normal state.

[0009] In conjunction with the first aspect, in one possible embodiment, the areas corresponding to the plurality of pins are encapsulated with a first insulating adhesive layer, which is applied after a vacuum process is first performed between the plurality of pins.

[0010] In conjunction with the first aspect, in one possible embodiment, it further includes an arc-extinguishing fusible link; a first cutting region is provided on the first conductive bus, a second cutting region is provided on the second conductive bus, and the signal fusible link is disposed between the first cutting region and the second cutting region; the second conductive bus is provided with a cutting weak portion; one end of the arc-extinguishing fusible link is connected to the end of the first cutting region away from the signal fusible link, and the other end of the arc-extinguishing fusible link is connected to the end of the cutting weak portion away from the signal fusible link; or, one end of the arc-extinguishing fusible link is connected to the end of the cutting weak portion close to the signal fusible link, and the other end of the arc-extinguishing fusible link is connected to the end of the cutting weak portion away from the signal fusible link.

[0011] In conjunction with the first aspect, in one possible embodiment, it further includes an impact member; the impact member includes a first substrate, a first impact end extending from a first end based on a first end face of the first substrate, and a second impact end extending from a second end based on a first end face of the first substrate; the first impact end is provided with at least two first cutting members, the at least two first cutting members being used to cut the first cutting region and the second cutting region when the impact member is pushed by high-pressure gas after being triggered by an excitation source; the second impact end is provided with at least one second cutting member, the at least one second cutting member being used to cut the cutting weak portion when the impact member is pushed by high-pressure gas after being triggered by an excitation source.

[0012] In conjunction with the first aspect, in one possible embodiment, a clamping member is further included; the clamping member is disposed below the signal melt and clamps onto the arc-extinguishing melt; after the at least two first cutting members cut the first cutting area and the second cutting area, they continue to impact the clamping member to push the clamping member to break the first clamped area of ​​the arc-extinguishing melt; or, the clamping member is disposed below the cutting weak portion and clamps onto the arc-extinguishing melt; after the at least one second cutting member cuts the cutting weak portion, they continue to impact the clamping member to push the clamping member to break the second clamped area of ​​the arc-extinguishing melt; or, the clamping member... The holder includes a first sub-clamping member and a second sub-clamping member; the first sub-clamping member is disposed below the signal melt and clamps onto the arc-extinguishing melt, and the second sub-clamping member is disposed below the cutting weak portion and clamps onto the arc-extinguishing melt; after the at least two first cutting members cut the first cutting area and the second cutting area, they continue to impact the clamping member to push the clamping member to break the first clamped area of ​​the arc-extinguishing melt; after the at least one second cutting member cuts the cutting weak portion, they continue to impact the second sub-clamping member to push the second sub-clamping member to break the second clamped area of ​​the arc-extinguishing melt.

[0013] In conjunction with the first aspect, in one possible embodiment, when two first cutting elements are provided on the first impact end, a first groove is provided between the two first cutting elements, and the shape of the first groove is adapted to the signal melt; when the impact element is pushed by high-pressure gas, causing the first cutting element and the second cutting element to move to the first cutting area and the second cutting area respectively, the signal melt is embedded in the first groove.

[0014] In conjunction with the first aspect, in one possible embodiment, an arc-extinguishing structure is further provided below the second conductive busbar; the arc-extinguishing structure includes a base, a support portion extending from one end of the base toward the second conductive busbar, and the support portion is provided at the end of the cutting weak portion near the signal melt; When the weak section is cut by the at least one second cutting member, the end of the weak section near the signal melt is supported so that the two ends of the weak section being cut are quickly separated.

[0015] As can be seen, the single-excitation-source integrated active and passive protection smart fuse in this application includes a first conductive bus, a signal fuse element, a second conductive bus, a circuit board, and an excitation source. The circuit board is equipped with the relay and the excitation source. The relay is connected to an external control unit, the excitation source, the first conductive bus, and the second conductive bus. The first conductive bus, the signal fuse element, and the second conductive bus are connected sequentially. An isolation layer is provided on the relay to shield it from crosstalk caused by external voltage. Multiple pins of the relay are soldered onto the circuit board, and these pins are insulated from each other. During inspection, the external control unit outputs a first inspection signal to the relay to control it to switch to inspection mode and provides feedback on the operating status of the excitation source to the external control unit. This enhances the radiation immunity and high / low voltage insulation design of the smart fuse, enabling the single-excitation-source smart fuse to simultaneously adapt to both external and internal triggering functions, and reducing the probability of the excitation source being mistriggered or failing to trigger properly due to interference. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of a trigger circuit provided in an embodiment of this application; Figure 2a This is a schematic diagram of the structure of the first type of smart fuse provided in the embodiments of this application; Figure 2b This is a schematic diagram of the structure of the first type of connection K provided in the embodiments of this application; Figure 3 This is a schematic diagram of the state after the first type of excitation source is triggered, as provided in the embodiments of this application; Figure 4 This is a schematic diagram of the structure of the second type of smart fuse provided in the embodiments of this application; Figure 5 This is a schematic diagram of the state after the second type of excitation source is triggered, as provided in the embodiments of this application; Figure 6 This is a schematic diagram of the structure of the third type of smart fuse provided in the embodiments of this application; Figure 7 This is a schematic diagram of the integrally formed first conductive bus, signal melt, and second conductive bus provided in the embodiments of this application. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0019] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, systems, products, or apparatuses.

[0020] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0021] To address the problems existing in the prior art, this application provides a single-excitation-source integrated active-passive protection smart fuse, including a first conductive bus, a signal fuse element, a second conductive bus, a circuit board, and an excitation source. The circuit board is equipped with the relay and the excitation source. The relay is connected to an external control unit, the excitation source, the first conductive bus, and the second conductive bus. The first conductive bus, the signal fuse element, and the second conductive bus are connected sequentially. An isolation layer is provided on the relay to shield it from crosstalk caused by external voltage. Multiple pins of the relay are soldered onto the circuit board, and these pins are insulated from each other. During inspection, the external control unit outputs a first inspection signal to the relay to control it to switch to inspection mode and provides feedback on the status of the excitation source to the external control unit. This enhances the radiation immunity and high / low voltage insulation design of the smart fuse, enabling the single-excitation-source smart fuse to simultaneously adapt to both external and internal triggering functions, and reducing the probability of false triggering or failure to trigger due to interference with the excitation source. This solution is applicable to various scenarios, including but not limited to the applications mentioned above.

[0022] The specific structure will be described in detail below.

[0023] Please see Figures 1 to 7 This application also provides a single-excitation-source active-passive integrated protection smart fuse, including a first conductive bus 10, a signal fuse 20, a second conductive bus 30, a circuit board 50 and an excitation source 40; The circuit board 50 is provided with the relay J1 and the excitation source 40. The relay J1 is connected to the external control unit 100, the excitation source 40, the first conductive bus 10, and the second conductive bus 30, respectively. The first conductive bus 10, the signal fuse 20, and the second conductive bus 30 are connected in sequence (e.g., ...). Figures 1 to 7 As shown), where, Figure 2b for Figure 2a As shown in the enlarged view of the connection point K, the signal fuse 20 can be connected across the first conductive bus 10 and the second conductive bus 30; whereby, Figure 2b The two enlarged images are schematic diagrams of the connection point K from different perspectives. Figure 2b The enlarged view in the upper left corner is a side view. Figure 2b The enlarged view in the lower left corner is a top view.

[0024] The relay J1 is provided with an isolation layer 52, which is used to shield the relay J1 from crosstalk caused by external voltage. After the multiple pins of the relay J1 are soldered onto the circuit board 50, the multiple pins are insulated from each other. During the inspection process, the external control unit 100 outputs a first inspection signal to the relay J1 to control the relay J1 to switch to the inspection state and to feed back the status of the excitation source 40 to the external control unit 100.

[0025] In specific implementation, the smart fuse in this application embodiment is equipped with a single excitation source (such as...). Figures 1 to 6 The excitation source 40 shown is connected to the external control unit 100 and two conductive bars (the first conductive bar 10 and the second conductive bar 30) respectively via relay J1. This allows the excitation source 40 to be triggered simultaneously by the external control unit 100, or to be passively triggered when the current in the main circuit of the smart fuse (the circuit of the first conductive bar 10, the signal fuse 20 and the second conductive bar 30) increases abnormally.

[0026] Specifically, relay J1 and excitation source 40 are both soldered onto circuit board 50 and connected through a circuit on circuit board 50. Circuit board 50 also includes diode D1, a first current limiting unit and a second current limiting unit. The first current limiting unit includes a first resistor R1 and a second resistor R2, and the second current limiting unit includes a third resistor R3 and a fourth resistor R4. The first resistor R1 and the second resistor R2 are connected in parallel as backups for each other, and the third resistor R3 and the fourth resistor R4 are connected in parallel as backups for each other. Pins 1 and 4 of relay J1 are connected to the high-level terminal of external control unit 100 and the cathode of diode D1. Pin 8 of relay J1 is connected to the anode of diode D1 and the low-level terminal of external control unit 100. Pin 2 of relay J1 is connected to the second busbar 30. Pin 7 of relay J1 is connected to one end of the third resistor R3 and one end of the fourth resistor R4. The other ends of the third resistor R3 and the fourth resistor R4 are connected to the first busbar 10. Pin 3 of relay J1 is connected to the first terminal of excitation source 40, and pin 6 of relay J1 is connected to the second terminal of excitation source 40. Pin 5 of relay J1 is connected to one end of the first resistor R1 and one end of the second resistor R2. The other ends of the first resistor R1 and the second resistor R2 are connected to the low-level terminal of external control unit 100. The high-level and low-level terminals of external control unit 100 are connected through diode D1 to prevent reverse electromotive force from being generated during circuit switching.

[0027] For example, the gap between the first conductive bus 10 and the second conductive bus 30 can be very small, such as 1 mm, or other spacing distances, which can be finely adjusted according to the actual situation and are not limited here. A thin metal sheet made of T2 copper, silver, or other metal material with a thickness of 0.1 mm is used as the signal melt 20. The signal melt 20 is connected in series between the gap between the first conductive bus 10 and the second conductive bus 30 by resistance or laser welding. The length of the signal melt 20 can be greater than the gap between the first conductive bus 10 and the second conductive bus 30, and a row of hollow structures is formed on the metal sheet. The hollow structures only need to be within the length range of the signal melt 20, such as 1 mm in diameter. The hollow structures can be round holes, wedges, or other shapes. Weak points are formed between every two hollow structures to improve the melting speed of the signal melt 20. Because the thickness of the signal melt 20 is very thin and the weak points are very fine, the arc energy generated when the signal melt 20 melts under abnormal current is small, and the arc is extinguished more easily.

[0028] Under normal operating conditions (no external drive signal, i.e., the voltage applied to L and H is 0), pins 2 and 3 of relay J1 are interconnected, and pins 6 and 7 are interconnected to conduct the internal trigger circuit, connecting the excitation source 40, the current-limiting resistors (the third resistor R3 and the fourth resistor R4), the first busbar, the signal fuse 20, and the second busbar. When an abnormal current causes the signal fuse 20 to melt, an extremely high arc voltage is generated across the signal fuse 20, which triggers the excitation source 40. The propellant in the excitation source 40 explodes, generating a large amount of high-pressure gas to control the smart fuse to cut off the main circuit.

[0029] In this embodiment, the external control unit 100 performs a routine inspection of the excitation source 40 at preset intervals. During the inspection, the external control unit 100 outputs a first inspection signal to the coil of the relay J1. After receiving the first inspection signal, the coil of the relay J1 switches its state to disconnect the main circuit and connect the external trigger circuit, interconnecting pins 3 and 4, and pins 6 and 5, so that the external control unit 100 is connected to the excitation source 40, enabling the external control unit 100 to detect the state of the excitation source 40. Specifically, if the external control unit 100 can detect the corresponding detection signal, it determines that the excitation source 40 is in a normal state and can be triggered under a suitable current; if the external control unit 100 fails to detect the corresponding detection signal or the parameters of the external trigger circuit are abnormal, it determines that the excitation source 40 is in a fault state, and then feeds back the fault information to the relevant personnel's electronic equipment. Optionally, after relay J1 turns on the external trigger circuit, the external control unit 100 applies the inspection voltage to the excitation source 40, the first resistor R1, and the second resistor R2. Therefore, the loop resistance of the external trigger circuit at this time can be calculated by the current and voltage, and the loop resistance can be used to determine whether the excitation source 40 is damaged and whether the drive circuit (the third resistor R3 and the fourth resistor R4) is normal, thus realizing the inspection of the excitation source 40.

[0030] When in external triggering mode, the external control unit 100 first outputs a second inspection signal to the relay J1 to control the relay J1 to switch to external triggering mode; then it outputs a trigger voltage to the relay J1, and when the trigger current corresponding to the trigger voltage is greater than a first current threshold and the duration of the trigger current is greater than a preset time, the relay J1 drives the excitation source 40 to trigger. For example, when the excitation source 40 needs to be triggered by the external control unit 100, the external control unit 100 first sends a second inspection signal to the coil of the relay J1. The second inspection signal can be the same as or different from the first inspection signal, as long as the corresponding second inspection current is less than the trigger signal of the excitation source 40; after receiving the second inspection signal, the coil magnet of the excitation source 40 is attracted to disconnect the main circuit and connect the external triggering circuit; then, the external control unit 100 outputs a trigger voltage (e.g., 8.4V) to the relay J1 to trigger the excitation source 40; optionally, the duration of the trigger voltage needs to exceed a preset time to ensure that the excitation source 40 can be accurately triggered and to avoid false triggering, thus achieving external triggering.

[0031] In addition, a first shielding copper foil is attached to the back of the circuit board 50 and grounded. The shielding copper foil can effectively shield the circuit board 50 from electromagnetic radiation, thereby enhancing the radiation immunity of the circuit board 50. The housing of the relay J1 is also equipped with an isolation layer 52, on which a second shielding copper foil is attached and grounded, thereby enhancing the radiation immunity of the relay J1. This allows the smart fuse in this embodiment to meet the relevant EMC (Electromagnetic Compatibility) test standards and improve the long-term reliability of the product under complex working conditions.

[0032] In one possible embodiment, the first current limiting unit is used to limit the first inspection current or the second inspection current to less than a second current threshold when the first inspection current corresponding to the first inspection signal or the second inspection current corresponding to the second inspection signal flows through the excitation source 40; the second current limiting unit is used to limit the current flowing through the excitation source 40 in the main circuit to less than the second current threshold under normal conditions.

[0033] In the specific implementation, the first resistor R1 and the second resistor R2 are set in the external triggering circuit to limit the current value flowing through the excitation source 40 to no more than 400mA (i.e., the second current threshold) when the external signal input terminal Vin inputs a patrol signal (such as the first patrol signal and the second patrol signal), so as to avoid the risk of false triggering of the excitation source 40; the third resistor R3 and the fourth resistor R4 are used to limit the shunting current of the branch current where the excitation source 40 is located to no more than 400mA when the normal current flows through the main circuit, so as to avoid the risk of false triggering of the excitation source 40.

[0034] At a certain moment during normal operation, when an external control circuit inputs a patrol signal (e.g., the first patrol signal and the second patrol signal), this voltage is first applied to the coil of relay J1. Based on the operating parameters of relay J1, relay J1 can complete the signal switching after 2-3ms. At this time, pins 3 and 6 of the output terminal of relay J1 are connected to pins 4 and 5 respectively, and a 2.3V patrol voltage is applied to the excitation source 40 and the first resistor R1 and the second resistor R2. The resistance values ​​of the first resistor R1 and the second resistor R2 are adjusted so that the current flowing through the excitation source 40 is less than 400mA. By detecting the current flowing through the trigger circuit PCB board, and then calculating the loop resistance at this time from the current and voltage, the resistance is used to determine whether the excitation source 40 is damaged and whether the trigger circuit is normal, thus realizing the patrol inspection of the excitation source 40 loop.

[0035] In one possible embodiment, the single-excitation-source active-passive integrated protection smart fuse further includes a first wire 41 and a second wire 42; a first through hole 11 is provided on the first conductive bus 10 or the second conductive bus 30, and a second through hole 51 is provided on the circuit board 50; one end of the first wire 41 is soldered to the first conductive bus 10, and one end of the second wire 42 is soldered to the second conductive bus 30; after one end of the first wire 41 is soldered to the first conductive bus 10 and one end of the second wire 42 is soldered to the second conductive bus 30, the first wire 41 and the second wire 42 are twisted together and then passed through the first through hole 11 and the second through hole 51 in sequence, and the other end of the first wire 41 and the other end of the second wire 42 are respectively connected to the relay J1 through the circuit board 50.

[0036] First conductor 41 and second conductor 42 are led out from the first conductive bus 10 and the second conductive bus 30 respectively by welding or bolting. Then, the first conductor 41 and the second conductor 42 are twisted together to form a twisted pair 43. The other end of the twisted pair 43 is then connected to the lead-out terminal of the circuit board 50 by welding or other means. Between the two ends of the twisted pair 43, a first through hole 11 is opened on the first conductive bus 10, and a second through hole 51 is opened on the circuit board 50. The twisted pair 43 passes through the first through hole 11 and the second through hole 51 respectively to connect from the first conductive bus 10 and the second conductive bus 30 to the lead-out terminal, so as to realize the connection between the relay J1 and the first conductive bus 10 and the second conductive bus 30.

[0037] Specifically, as the twisted pair 43 travels from the first conductive busbar 10 and the second conductive busbar 30 to the circuit board 50, its path avoids the impact path of the impact member 60 to prevent deviation of the impact path.

[0038] Since the signal fuse 20, the first wire 41, the second wire 42 and the lead-out end of the circuit board 50 also form a coil, the connecting wire here uses multi-core shielded twisted pair cable to increase the radiation shielding capability of the twisted pair cable 43; at the same time, the first wire 41 and the second wire 42 are wound together to reduce the area of ​​this coil, which makes it easier for the twisted pair cable 43 to avoid the impact path.

[0039] In one possible embodiment, the areas corresponding to the plurality of pins are encapsulated with a first insulating adhesive layer 53, which is applied after vacuuming the plurality of pins.

[0040] In practice, when the signal fuse 20 melts due to abnormal current, an electric arc will be generated between the fuse fragments, exhibiting a very high arc voltage. This arc voltage will severely test the insulation capability of the relay J1 in the trigger circuit. The insulation treatment of the multiple pins refers to the fact that the relay J1 is simultaneously connected to both high and low voltage. Therefore, a relay J1 with high dielectric withstand voltage (between coil and contacts, between disconnected contacts, and between contact groups) and high surge voltage needs to be selected. Simultaneously, the soldered pins of the relay J1 are reinforced with vacuuming and potting with a first insulating adhesive layer 53 to enhance the insulation capability between high and low voltage. Furthermore, a second insulating adhesive layer is provided on the exposed solder joints on the back of the circuit board 50 to further enhance the insulation capability. Both the first insulating adhesive layer 53 and the second insulating adhesive layer can be epoxy resin, silicone gel, or other insulating materials, and no unique limitation is imposed here.

[0041] In one possible embodiment, please refer to the following: Figures 2a to 5 The single-excitation-source active-passive integrated protection smart fuse also includes an arc-extinguishing fuse element 70; a first cutting area 12 is provided on the first conductive bus 10, and a second cutting area 13 is provided on the second conductive bus 30; the signal fuse element 20 is disposed between the first cutting area 12 and the second cutting area 13; the second conductive bus 30 is provided with a cutting weak part 31 (such as... Figure 2a and Figure 4 (The dashed box portion in the text); one end of the arc-extinguishing melt 70 is connected to the end of the first cutting region 12 away from the signal melt 20, and the other end of the arc-extinguishing melt 70 is connected to the end of the cutting weak portion 31 away from the signal melt 20; or, one end of the arc-extinguishing melt 70 is connected to the end of the cutting weak portion 31 close to the signal melt 20, and the other end of the arc-extinguishing melt 70 is connected to the end of the cutting weak portion 31 away from the signal melt 20.

[0042] Furthermore, the smart fuse also includes an impact member 60; the impact member 60 includes a first substrate 61, a first impact end extending from a first end of a first end face 62 of the first substrate 61, and a second impact end extending from a second end of the first end face 62 of the first substrate 61; at least two first cutting members 63 are provided on the first impact end, the at least two first cutting members 63 being used to cut off the first cutting region 12 and the second cutting region 13 when the impact member 60 is pushed by high-pressure gas after being triggered by the excitation source 40; at least one second cutting member 64 is provided on the second impact end. Figures 2a to 5 Only two examples of second cut-off members 64 are given, but it is understood that one second cut-off member 64 can also achieve the corresponding function. The at least one second cut-off member 64 is used to cut off the cut-off weak part 31 when the impact member 60 is pushed by high-pressure gas after being triggered by the excitation source 40.

[0043] In the specific implementation, refer to Figure 1 , Figure 2a and Figure 3 Under normal conditions, current flows through the first conductive busbar 10, the signal fuse 20, and the second conductive busbar 30. In the arc-extinguishing fuse 70 branch, since its resistance is much greater than that of the second conductive busbar 30, almost no current flows through the arc-extinguishing fuse 70.

[0044] For example, the length of the first cutting element 63 is greater than that of the second cutting element 64. If, at a certain moment in normal operation, the external control circuit has no input voltage and a large abnormal current suddenly occurs in the main circuit, the signal fuse 20 will melt under the action of the abnormally large current. During the melting process, an electric arc is generated, accompanied by an extremely high arc voltage. At this time, the excitation source 40 is connected to the third resistor R3 and the fourth resistor R4 and the signal fuse 20. The arc voltage generated by the melting of the signal fuse 20 is sufficient to trigger the excitation source 40, causing the gunpowder inside to explode, releasing a large amount of gas, generating a great pressure in the sealed cavity, and pushing the impact element 60 downward. Because at least one second cutting element 64 is pressed tightly on the cutting weak part 31, the second conductive bus 30 is quickly cut off, and the arc current flows through the arc extinguishing fuse 70. At least two first cutting elements 63 then fall onto the first cutting area 12 and the second cutting area 13, cutting the signal fuse 20 off the first conductive bus 10 and the second conductive bus 30, thereby completely disconnecting the main circuit. Furthermore, due to the large distance between the signal fuse 20 and the weak cutting portion 31, a sufficient insulation distance can be formed in the main circuit. After the arc-extinguishing fuse 70 is melted, the arc-extinguishing current is extinguished by the cooling effect of the arc-extinguishing material, thus achieving safety protection. Moreover, by placing the second cutting element 64 close to the weak cutting portion 31, the cutting speed can be increased when an abnormally large current is generated, thereby improving the overall response speed of the smart fuse.

[0045] In one possible embodiment, cutting the weak portion 31 includes cutting at least one weak region, and the number of second cutting members 64 is the same as the number of weak regions 32; that is, when there is one weak region 32, there is also one second cutting member 64; when there are multiple weak regions 32, there are also multiple second cutting members 64. The second cutting members 64 correspond one-to-one with the weak regions 32 and are in close contact with the corresponding weak regions 32.

[0046] For example, the length of the first cutting member 63 can also be less than that of the second cutting member 64. In this way, the signal melt 20 can be cut off first, and then the weak part 31 and the arc-extinguishing melt 70 can be cut off by the second cutting member 64. The choice can be made according to the actual situation and is not limited here.

[0047] In one possible embodiment, the upper end of the impact member 60 forms a concave cavity 65, which forms a sealed space with the excitation source 40. After the gunpowder in the excitation source 40 explodes, a large amount of gas will be released in this sealed space, thereby generating pressure and pushing the impact member 60 to move along the impact path.

[0048] In one possible embodiment, the smart fuse further includes a clamping member 81; the clamping member 81 is disposed below the signal fuse 20 and clamps the arc-extinguishing fuse 70; after the at least two first cutting members 63 cut the first cutting area 12 and the second cutting area 13, they continue to impact the clamping member 81 to push the clamping member 81 to break the first clamped area of ​​the arc-extinguishing fuse 70; or, the clamping member 81 is disposed below the cutting weak portion 31 and clamps the arc-extinguishing fuse 70; after the at least one second cutting member 64 cuts the cutting weak portion 31, it continues to impact the clamping member 81 to push the clamping member 81 to break the second clamped area of ​​the arc-extinguishing fuse 70; or, the clamping member 81 includes A first sub-clamping member 811 and a second sub-clamping member 812; the first sub-clamping member 811 is disposed below the signal melt 20 and clamps the arc-extinguishing melt 70, and the second sub-clamping member 812 is disposed below the cutting weak portion 31 and clamps the arc-extinguishing melt 70; after the at least two first cutting members 63 cut the first cutting area 12 and the second cutting area 13, they continue to impact the clamping member 81 to push the clamping member 81 to break the first clamped area of ​​the arc-extinguishing melt 70; after the at least one second cutting member 64 cuts the cutting weak portion 31, it continues to impact the second sub-clamping member 812 to push the second sub-clamping member 812 to break the second clamped area of ​​the arc-extinguishing melt 70.

[0049] In the specific implementation, refer to Figure 4 and Figure 5 The first end of the arc-extinguishing melt 70 is connected in parallel to the front end of the weak point in the first conductive busbar 10 (i.e., the end away from the signal melt 20), and the second end of the arc-extinguishing melt 70 is connected in parallel to the rear end of the weak point in the second conductive busbar 30 (i.e., the end away from the signal melt 20). Thus, the signal melt 20 and the weak point 31 are both connected in parallel with the arc-extinguishing melt 70. Under normal circumstances, the overall resistance of the signal melt 20, the second conductive busbar 30, and the weak point 31 is much smaller than the resistance of the arc-extinguishing melt 70, and the current basically does not flow through the arc-extinguishing melt 70.

[0050] The two impact ends (first impact end and second impact end) of the impact member 60 are located at the top, and the heights of the two impact ends may be equal or unequal. For example... Figure 5As shown, a clamping member 81 is provided on the arc-extinguishing melt 70 below either the first impact end or the second impact end to clamp the arc-extinguishing melt 70. When the impact end moves downward to a certain position, it will drive the clamping member 81 to move downward at the same time, thereby cutting off the arc-extinguishing melt 70. This enables the main circuit to be completely disconnected when the external signal triggers the excitation source 40 to operate under low current conditions.

[0051] It is understandable that clamping members 81 can be provided below both the first and second impact ends to clamp the arc-extinguishing melt 70, that is, two clamping members 81 can be provided to ensure that the arc-extinguishing melt 70 can be completely cut off.

[0052] In one possible embodiment, when two first cutting elements 63 are provided on the first impact end, a first groove 66 is provided between the two first cutting elements 63; when the impact element 60 is pushed by high-pressure gas, causing the first cutting element 63 and the second cutting element 64 to move to the first cutting region 12 and the second cutting region 13 respectively, the signal melt 20 is embedded in the first groove 66.

[0053] In the specific implementation, a first groove 66 adapted to the signal melt 20 is set so that when the impact member 60 cuts the two conductive bars, the signal melt 20 can be wrapped up, avoiding displacement of the signal melt 20 and forming unnecessary arcing, thus ensuring arc extinguishing efficiency.

[0054] Specifically, the shape of the first groove 66 can be larger than the size of the signal melt 20, as long as it can enclose the signal melt 20; no unique limitation is imposed here. The specific shape of the first groove 66 can be adjusted according to actual production conditions, such as hemispherical, square, etc.; no unique limitation is imposed here.

[0055] In one possible embodiment, the smart fuse further includes an arc-extinguishing structure 80 disposed below the second conductive bus 30; the arc-extinguishing structure 80 includes a base, and a support portion 82 extends from one end of the base toward the second conductive bus 30, and the support portion 82 is disposed at one end of the cutting weak portion 31 near the signal fuse 20; when the cutting weak portion 31 is cut by the at least one second cutting member 64, the end of the cutting weak portion 31 near the signal fuse 20 is supported so that the two ends of the cutting weak portion 31 are quickly separated.

[0056] In the specific implementation, refer to Figure 6The second conductive busbar 30 has a cutting weak region 32 and a bending weak region 33. Correspondingly, the second impact end of the impact member 60 is on the impact path of the cutting weak region 32. An arc-extinguishing structure 80 is provided in the space below the second conductive busbar 30. It is first pre-pressed into a specific shape using metal wire mesh, preferably stainless steel wire mesh, and then installed into the arc-extinguishing chamber below the second conductive busbar 30. Furthermore, the arc-extinguishing structure 80 can also be impregnated and cured with silicone rubber, melamine-formaldehyde resin solution, etc., after pressing and molding, and then installed into the arc-extinguishing chamber to improve the arc-extinguishing effect. When the excitation source 40 is triggered, the impact member 60 moves along the impact path. After its second impact end breaks the corresponding weak cutting area 32, it continues to move along the impact path, bending the second conductive busbar 30 to one side along the bending weak area 33. The electric arc generated by the melting breaking is blown into the arc extinguishing structure 80 made of metal wire mesh in the arc extinguishing chamber. The arc is extinguished by the cooling of the arc extinguishing structure 80. The impregnated metal wire mesh can also increase the arc extinguishing effect and improve the breaking capacity of the product by the decomposition of the impregnating material and the generation of gas.

[0057] In one possible embodiment, refer to Figure 7 The first conductive bus 10, the signal melt 20, and the second conductive bus 30 are all formed on the same piece of metal conductor through processes such as stamping and thinning, in order to reduce the difficulty of the process and make the product more adaptable. First, a section of metal conductor is stamped at a specific position to form two first cutting regions 12 and at least two cutting weak regions 32. The required thickness of the signal melt 20 is made by mechanical thinning between the two first cutting regions 12. Then, the neck 21 of the signal melt 20 is obtained by punching. It can be understood that when the second conductive bus 30 is provided with two or more cutting weak regions 32, the required neck 21 of the conductive bus melt M1 can also be obtained by punching at the position of at least one cutting weak region 32 in the middle.

[0058] In this embodiment, the first conductive bus 10, the signal melt 20, and the second conductive bus 30 are all formed on the same metal conductor, which reduces the contact resistance in the welding process and improves product reliability. On the other hand, the signal fuse 20 and the busbar fuse M1 can be designed to melt under different currents. For example, under a small abnormal current, the signal fuse 20 melts, the input energy is small, and the arc is easily extinguished. When there is a large abnormal current, the signal fuse 20 and the busbar fuse M1 melt almost simultaneously, instantly widening the distance between the fracture surfaces, which is more conducive to the extinguishing of high energy density arcs.

[0059] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can easily conceive of variations or substitutions without departing from the spirit and scope of the present invention, and various modifications and alterations can be made, including combinations of the different functions and implementation steps described above, as well as software and hardware implementation methods, all of which are within the protection scope of the present invention.

Claims

1. A single-excitation-source integrated active and passive protection intelligent fuse, characterized in that, It includes a first busbar, a signal fuse, a second busbar, a circuit board, a relay, and an excitation source; The circuit board is provided with the relay and the excitation source. The relay is connected to the external control unit, the excitation source, the first busbar and the second busbar respectively. The first busbar, the signal fuse and the second busbar are connected in sequence. The relay is provided with an isolation layer, which is used to shield the relay from crosstalk caused by external voltage. After the multiple pins of the relay are soldered onto the circuit board, the multiple pins are insulated from each other. During the inspection process, the external control unit outputs a first inspection signal to the relay to control the relay to switch to the inspection state and to provide feedback on the status of the excitation source to the external control unit.

2. The single-excitation-source active-passive integrated protection intelligent fuse according to claim 1, characterized in that, It also includes a first conductor and a second conductor; a first through hole is formed on the first conductive bar or the second conductive bar, and a second through hole is formed on the circuit board; One end of the first wire is soldered to the first conductive busbar, and one end of the second wire is soldered to the second conductive busbar; After one end of the first wire is soldered to the first conductive busbar and one end of the second wire is soldered to the second conductive busbar, the first wire and the second wire are twisted together and then passed through the first through hole and the second through hole in sequence. The other ends of the twisted first wire and the other ends of the second wire are respectively connected to the relay through the circuit board.

3. The single-excitation-source integrated active and passive protection intelligent fuse according to claim 2, characterized in that, When in an externally triggered operating condition, the external control unit first outputs a second inspection signal to the relay to control the relay to switch to the externally triggered state; Then, a trigger voltage is output to the relay, and when the trigger current corresponding to the trigger voltage is greater than the first current threshold and the duration of the trigger current is greater than a preset time, the relay drives the excitation source to trigger.

4. The single-excitation-source integrated active and passive protection intelligent fuse according to claim 3, characterized in that, It also includes a first current limiting unit and a second current limiting unit; the first current limiting unit is used to limit the first inspection current or the second inspection current corresponding to the first inspection signal or the second inspection current corresponding to the second inspection signal to less than a second current threshold when the excitation source flows through the excitation source; the second current limiting unit is used to limit the current flowing through the excitation source in the main circuit to less than the second current threshold when the excitation source is in normal state.

5. The single-excitation-source integrated active and passive protection intelligent fuse according to claim 4, characterized in that, The areas corresponding to the plurality of pins are encapsulated with a first insulating adhesive layer, which is applied after vacuuming the plurality of pins.

6. The single-excitation-source active-passive integrated protection intelligent fuse according to claim 5, characterized in that, It also includes an arc-extinguishing melt; a first cutting area is provided on the first conductive bus, a second cutting area is provided on the second conductive bus, and the signal melt is disposed between the first cutting area and the second cutting area; the second conductive bus is provided with a cutting weak section; One end of the arc-extinguishing melt is connected to the end of the first cutting region away from the signal melt, and the other end of the arc-extinguishing melt is connected to the end of the cutting weak portion away from the signal melt; or, one end of the arc-extinguishing melt is connected to the end of the cutting weak portion close to the signal melt, and the other end of the arc-extinguishing melt is connected to the end of the cutting weak portion away from the signal melt.

7. The single-excitation-source integrated active and passive protection intelligent fuse according to claim 6, characterized in that, It also includes impact components; The impact member includes a first substrate, a first impact end extending from a first end based on a first end face of the first substrate, and a second impact end extending from a second end based on a second end face of the first substrate; The first impact end is provided with at least two first cutting elements, which are used to cut off the first cutting area and the second cutting area when the impact element is pushed by high-pressure gas after being triggered by the excitation source; The second impact end is provided with at least one second cutting element, which is used to cut off the cutting weak part when the impact element is pushed by high-pressure gas after being triggered by the excitation source.

8. The single-excitation-source active-passive integrated protection intelligent fuse according to claim 7, characterized in that, It also includes clamping components; The clamping member is positioned below the signal melt and clamps onto the arc-extinguishing melt; after the at least two first cutting members cut the first cutting area and the second cutting area, they continue to impact the clamping member to push it to break off the first clamped area of ​​the arc-extinguishing melt; or... The clamping member is positioned below the weak cutting portion and clamps onto the arc-extinguishing melt; after the at least one second cutting member cuts the weak cutting portion, it continues to impact the clamping member to push the clamping member to break through the second clamped area of ​​the arc-extinguishing melt; or... The clamping member includes a first sub-clamping member and a second sub-clamping member; the first sub-clamping member is disposed below the signal melt and clamps the arc-extinguishing melt, and the second sub-clamping member is disposed below the cutting weak portion and clamps the arc-extinguishing melt; after the at least two first cutting members cut the first cutting area and the second cutting area, they continue to impact the clamping member to push the clamping member to break the first clamped area of ​​the arc-extinguishing melt; after the at least one second cutting member cuts the cutting weak portion, they continue to impact the second sub-clamping member to push the second sub-clamping member to break the second clamped area of ​​the arc-extinguishing melt.

9. The single-excitation-source integrated active and passive protection intelligent fuse according to claim 7, characterized in that, When two first cutting elements are provided on the first impact end, a first groove is provided between the two first cutting elements; When the impactor is pushed by high-pressure gas, causing the first cutting element and the second cutting element to move to the first cutting area and the second cutting area respectively, the signal melt is embedded in the first groove.

10. The single-excitation-source active-passive integrated protection intelligent fuse according to any one of claims 6-9, characterized in that, It also includes an arc-extinguishing structure disposed below the second conductive busbar; the arc-extinguishing structure includes a base, and a support portion extends from one end of the base toward the second conductive busbar, and the support portion is disposed at the end of the cutting weak portion near the signal melt; When the weak section is cut by the at least one second cutting member, the end of the weak section near the signal melt is supported so that the two ends of the weak section being cut are quickly separated.

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