Low-voltage single-phase circuit breaker

Abstract

The invention relates to a low-voltage single-phase circuit breaker, which relates to the technical field of power equipment, and comprises an insulating bracket, and the insulating bracket is provided with a vacuum protection device for overload protection, a fusing protection device for short-circuit protection, an opening and closing device for connecting and disconnecting a circuit, and a thermosensitive device for overheating protection. The thermosensitive device comprises a shape memory alloy, a trigger plate, a wedge block and the like, the fusing protection device comprises a contact, and the opening and closing device comprises a permanent magnet assembly, a double-rocker assembly and an auxiliary switch. After being heated, the shape memory alloy can trigger a series of actions to realize functions of circuit disconnection and the like. According to the invention, overload, short circuit and overheating protection can be carried out on the low-voltage single-phase circuit, and all protection devices cooperate with each other, so that the circuit can be timely and effectively disconnected under different fault conditions, and safe and stable operation of the circuit is guaranteed.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of power equipment, in particular to a low-voltage single-phase circuit breaker. BACKGROUND

[0002] In the power system, the low-voltage single-phase circuit breaker is an important device to ensure the safe operation of the circuit. With the continuous growth of power demand and the increasing diversification of electrical equipment, higher requirements are put forward for the performance and reliability of the low-voltage single-phase circuit breaker. The low-voltage single-phase circuit breaker is widely used in electrical systems in various fields such as homes, businesses and industries, and its stable and reliable operation is crucial to ensure the normal work of electrical equipment and personnel safety. It can cut off the circuit in time when abnormal conditions occur in the circuit to prevent electrical accidents and provide an important guarantee for the stable operation of the power system.

[0003] In related technologies, in order to realize protection of the circuit, a single protection device or a combination of limited protection methods is usually adopted. For example, some circuit breakers rely only on fuses to achieve short-circuit protection, and when a short circuit occurs in the circuit, the fuse melts to cut off the circuit; for overload protection, some use thermal trippers that use the heat generated by the current passing through the heating element to deform the bimetallic strip, thereby triggering the tripping mechanism to cut off the circuit. In terms of opening and closing control, traditional circuit breakers mostly use electromagnetic or electric operating mechanisms to realize the connection and disconnection of the circuit. These conventional means can meet the basic circuit protection requirements to some extent, but there are certain limitations in actual application.

[0004] However, since different protection devices operate independently, there is a lack of effective coordination mechanism, and when multiple fault conditions occur in the circuit, it is difficult to achieve comprehensive and timely protection. For example, a single fuse can only respond to short-circuit faults and cannot provide effective protection for overload and overheating faults; thermal trippers have a certain effect on overload protection, but their response speed to short-circuit faults is slow. The limitations of such protection functions make traditional low-voltage single-phase circuit breakers unable to provide reliable protection when facing complex circuit faults, which can easily lead to damage to electrical equipment and even cause safety accidents. SUMMARY

[0005] The application aims to overcome the above technical problems and provides a low-voltage single-phase circuit breaker.

[0006] A low-voltage single-phase circuit breaker, comprising an insulating support, the insulating support being provided with a vacuum protection device for overload protection, a fuse protection device for short-circuit protection, an opening and closing device for connecting and disconnecting the circuit, and a thermal sensitive device for overheating protection. The thermal sensitive device comprises: The shape memory alloy is arranged on the opening and closing device, and the shape memory alloy is provided with a soft metal sheet used for connecting the circuit; The trigger plate is arranged on the insulating support, and the trigger plate is in abutment with the shape memory alloy, and the shape memory alloy controls the sliding of the trigger plate on the insulating support; The wedge-shaped block is arranged on the insulating support, and the wedge-shaped block is in clamping connection with the trigger plate, and the wedge-shaped block is connected with a trigger spring, and the trigger spring is in abutment with the insulating support; The fuse protection device comprises a contact, and the contact is in sliding connection with the insulating support; The shape memory alloy and the soft metal sheet are provided with a connecting head, and the connecting head is in abutment with the contact; The trigger spring is started after the shape memory alloy is heated, and the trigger spring drives the wedge-shaped block to disconnect the connecting head and the contact.

[0007] By adopting the above technical scheme, the vacuum protection device can realize overload protection, the fuse protection device can realize short-circuit protection, the opening and closing device can be connected and disconnected with the circuit, and the thermal sensitive device can realize overheat protection; the shape memory alloy is provided with the soft metal sheet to connect the circuit; the shape memory alloy controls the sliding of the trigger plate on the insulating support, the trigger plate is in clamping connection with the wedge-shaped block, the trigger spring is started after the shape memory alloy is heated, and the trigger spring drives the wedge-shaped block to disconnect the connecting head and the contact, so that the circuit can be disconnected in time when overheating occurs, and the safety of the circuit is ensured.

[0008] Preferably, the opening and closing device comprises a permanent magnet assembly, a double rocker assembly and an auxiliary switch; the permanent magnet assembly comprises a closing and opening rod, the closing and opening rod is connected with the double rocker assembly, and the double rocker assembly is connected with an insulator; the auxiliary switch is used to drive the closing and opening rod to slide, the double rocker assembly controls the connection or disconnection of the insulator with the vacuum protection circuit breaker, and the soft metal sheet and the shape memory alloy are connected with the insulator.

[0009] By adopting the above technical scheme, the opening and closing device is provided with the permanent magnet assembly, the double rocker assembly and the auxiliary switch, the closing and opening rod of the permanent magnet assembly is connected with the double rocker assembly, the double rocker assembly is connected with the insulator, the auxiliary switch drives the closing and opening rod to slide, the double rocker assembly controls the connection or disconnection of the insulator with the vacuum protection circuit breaker, and the soft metal sheet and the shape memory alloy are connected with the insulator, so that the connection and disconnection of the circuit can be realized, and the thermal sensitive device is associated with the opening and closing device to better realize overheat protection.

[0010] Preferably, the insulating support is provided with a driving groove, the trigger plate slides in the driving groove, the bottom of the driving groove is provided with a pressure sensor, the pressure sensor is electrically connected with the auxiliary switch, the shape memory alloy is in abutment with the pressure sensor after being heated, and the pressure sensor drives the auxiliary switch to operate.

[0011] By adopting the above technical scheme, the driving groove is arranged on the insulating support, the trigger plate slides in the driving groove, the pressure sensor electrically connected with the auxiliary switch is arranged at the bottom of the driving groove, the shape memory alloy drives the trigger plate to abut against the pressure sensor after being heated, the auxiliary switch can be driven to operate, the automatic control of the auxiliary switch during overheat protection is realized, and the circuit safety is further ensured.

[0012] Preferably, the wedge-shaped plate is provided with a clamping groove, and the trigger plate is provided with a clamping block extending into the clamping groove, and the shape memory alloy drives the clamping block to extend out of the clamping groove after being heated.

[0013] By adopting the above technical scheme, the low-voltage single-phase circuit breaker has the functions of overload protection, short-circuit protection, overheat protection and circuit connection disconnection, the shape memory alloy in the thermal sensitive device can control the trigger plate to slide after being heated, the wedge-shaped plate is provided with a clamping groove, the trigger plate is provided with a clamping block extending into the clamping groove, and the shape memory alloy drives the clamping block to extend out of the clamping groove after being heated, so that the trigger spring can be started, the wedge-shaped block drives the connecting head to disconnect from the contact, and the circuit is cut off during overheat protection.

[0014] Preferably, the insulating support is provided with an inclined block, the inclined block is provided with a first strip-shaped block, the wedge-shaped plate is provided with a second strip-shaped block, the trigger spring drives the first strip-shaped block to slide along the inclined block and be clamped with the second strip-shaped block, and the wedge-shaped block drives the contact to slide away from the connecting head.

[0015] By adopting the above technical scheme, the insulating support is provided with the inclined block and the first strip-shaped block, the wedge-shaped plate is provided with the second strip-shaped block, the trigger spring drives the first strip-shaped block to slide along the inclined block and be clamped with the second strip-shaped block, the distance between the connecting head and the contact can be increased, the contact is prevented from sliding off due to the sliding of the wedge-shaped block, the wedge-shaped block drives the contact to slide away from the connecting head, the reliable disconnection of the connecting head and the contact can be realized, and the low-voltage single-phase circuit breaker structure is matched, so that various protection functions such as overload protection, short-circuit protection and overheat protection are realized.

[0016] Preferably, the double-rocker assembly comprises a support frame, short connecting plates are rotationally arranged on the two sides of the support frame, the end portions of the two short connecting plates are rotationally connected through a connecting rod, a long connecting plate is rotationally arranged on the side surface of the short connecting rod, and the end portion of the long connecting plate is rotationally connected with the insulator.

[0017] By adopting the above technical scheme, the opening and closing device of the low-voltage single-phase circuit breaker can drive the double-rocker assembly to operate through the opening and closing rods of the permanent magnet assembly, the short connecting plates on the two sides of the support frame of the double-rocker assembly are connected through the connecting rod, the long connecting plate on the side surface of the short connecting rod is rotationally connected with the insulator, the connection or disconnection of the insulator and the vacuum insulation circuit breaker is realized, the connection and disconnection of the circuit are further realized, and the opening and closing control during overheat protection of the circuit can be realized in cooperation with the shape memory alloy and the soft metal sheet of the thermal sensitive device.

[0018] Preferably, the vacuum protection device comprises a vacuum arc-extinguishing device, and the vacuum arc-extinguishing device is provided with a plug-in hole into which the insulator is inserted.

[0019] By using the above technical solution, the vacuum arc-extinguishing device can realize overload protection, and the insulator is inserted into the plug-in hole of the vacuum arc-extinguishing device to realize the butt joint of the insulator and the vacuum arc-extinguishing device, so that the circuit breaker has the function of overload protection.

[0020] Preferably, the connecting head is provided with a plug, the plug is inserted on the nozzle, the nozzle is connected with a gas tank through a pipeline, the gas tank is filled with inert gas; the connection position of the nozzle and the plug is provided with a rubber ring, and the rubber ring is in contact with the surface of the plug.

[0021] By using the above technical solution, the shape memory alloy triggers the spring to start after being heated, which can drive the wedge-shaped block to disconnect the connecting head and the contact, thereby realizing overheating protection; the connecting head is provided with the plug inserted on the nozzle, the nozzle is connected with the gas tank filled with inert gas, when the temperature in the control cavity rises and the shape memory alloy deforms, the plug is pulled out of the nozzle, and the inert gas can be sprayed out; the rubber ring is in contact with the surface of the plug, which can preliminarily fix the position of the connecting plate and the connecting head, and avoid poor contact between the connecting head and the contact.

[0022] In summary, the present application has at least one of the following beneficial technical effects: 1. The insulating support is provided with a vacuum protection device, a fuse protection device, a switching device and a thermal device, which realizes overload protection, short circuit protection, overheating protection and circuit connection disconnection, solves the problem of single protection function of the traditional circuit breaker, and comprehensively protects various faults; 2. The shape memory alloy triggers the spring to start after being heated, which drives the wedge-shaped block to disconnect the connecting head and the contact, timely cuts off the circuit when overheating, and avoids damage to electrical equipment and safety accidents; 3. The shape memory alloy drives the trigger plate to be in contact with the pressure sensor when heated, the pressure sensor drives the auxiliary switch to operate, realizes automatic control of switching when overheating, and improves the timeliness and reliability of circuit protection.

[0023] 4. The internal structure layout of the low-voltage circuit breaker is optimized, which makes it more compact and miniaturized, facilitates installation and maintenance, and reduces production cost; 5. Through advanced control technology and intelligent controllers, the application can realize precise on-off time control. When a short circuit fault occurs in the power system, the quick cut-off within 10 ms combined with the relay response within 20 ms helps to realize better cooperation between different protection devices. This design has many advantages and unique operation logic in the power protection system. In normal operation, the current is at a relatively low level and below 40 kA, and the circuit breaker can stably carry and control the on-off of the current, ensuring the normal power supply of the power line. The circuit breaker has multiple protection functions and intelligent control capabilities, and can monitor and respond to abnormal conditions such as overload and undervoltage in the line, to a certain extent, maintaining the stable operation of the power system. When a fault occurs and the current exceeds 40 kA or reaches a high current state, the fuse plays a role in blocking. The fuse has fast response and strong current cut-off capability, and its fuse will melt quickly when a large current passes through, forming a reliable cut-off. In the case of high current, the severity and urgency of the fault require extremely fast cut-off means, and the fuse can cut off the current in a very short time to prevent catastrophic damage to the entire power system caused by excessive current, such as avoiding wire overheating and fire, equipment damage, etc., thereby ensuring the safety of the power system. Moreover, this cooperative working mode of the circuit breaker and the fuse realizes hierarchical protection. The circuit breaker takes advantage of its precise control and repeatable operation in normal and certain fault currents, while the fuse provides ultimate and one-time fast protection in extreme high current situations, complementing each other to improve the reliability, flexibility and comprehensiveness of power system protection, which helps to optimize the design and operation of the power system, reduce overall protection costs and extend equipment life; 6. Independent one-way modules, any combination. Each independent one-way module is equipped with standardized interfaces, including input and output interfaces. These interfaces adopt unified specifications and connection methods to ensure quick and reliable connection without complex debugging; 7. Quick and simple replacement of fuses, using a convenient plug-in structure design, significantly shortening replacement time, improving operation safety, and reducing operation and maintenance costs, so as to quickly send power. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a schematic diagram of the overall structure of the present application; Figure 2 is a schematic diagram of the overall structure of the present application, mainly the transmission screw rod; Figure 3 is a schematic diagram of the structure of the present application, mainly embodying the auxiliary switch; Figure 4 is a schematic diagram of the structure of the present application, mainly embodying the on-off lever; Figure 5It is a structural schematic diagram of the present application, mainly embodying the short connecting plate, the long connecting plate and the support frame. Figure 6 It is a sectional structural schematic diagram of the present application, mainly embodying the connecting head and the contact. Figure 7 It is a structural schematic diagram of the present application, mainly embodying the mounting plate. Figure 8 It is a sectional structural schematic diagram of the present application, mainly embodying the nozzle.

[0025] BRIEF DESCRIPTION OF DRAWINGS: 1, insulating support; 2, mounting column; 3, drawer panel; 4, fuse unit nameplate; 5, factory coding nameplate; 6, on-off indication; 7, on-off button assembly; 8, operation procedure; 9, handle; 10, guide bar; 11, guide groove; 12, grounding copper sheet; 13, baffle; 14, rotating hole; 15, dust cover; 16, transmission screw; 17, threaded groove; 18, first gasket; 19, screw spring; 20, support plate; 21, secondary plug-in component; 22, guide rod; 23, switch cavity; 24, mounting cavity; 25, control cavity; 26, driving cavity; 27, auxiliary switch; 28, power connection plate; 29, permanent magnet assembly; 30, on-off lever; 31, debugging buffer; 32, support frame; 33, short connecting plate; 34, connecting rod; 35, long connecting plate; 36, fixed rod; 37, positioning groove; 38, positioning plate; 39, positioning hole; 40, insulator; 41, plug; 42, vacuum arc extinguisher; 43, power outlet; 44, fixed column; 45, fuse; 46, connecting copper plate; 47, power inlet; 48, soft connecting component; 49, contact; 50, adapter column; 51, adapter groove; 52, shape memory alloy; 53, soft metal sheet; 54, clamping plate; 55, second gasket; 56, connecting head; 57, driving groove; 58, pressure sensor; 59, trigger plate; 60, pressing plate; 61, limiting groove; 62, wedge-shaped block; 63, arc-shaped groove; 64, clamping hole; 65, clamping groove; 66, clamping block; 67, trigger spring; 68, inclined surface block; 69, strip-shaped block; 70, strip-shaped groove; 71, mounting plate; 72, gas tank; 73, nozzle; 74, rubber ring; 75, connecting plate; 76, plug. DETAILED DESCRIPTION

[0026] The following will be described in detail in combination with the accompanying drawings. Figure 1 - the accompanying drawings Figure 8 The present application will be further described in detail.

[0027] A low-voltage single-phase circuit breaker, referring to Figure 1 , comprising an insulating support 1, the insulating support 1 being provided with a vacuum protection device for overload protection, a fuse protection device for short-circuit protection, an on-off device for connecting and disconnecting a circuit, and a thermal sensitive device for overheat protection.

[0028] Referring toFigure 1 、 Figure 2 , the insulating support 1 is fixedly connected with a plurality of installation columns 2 on one side, and the end of the installation column 2 is fixedly connected with a drawer panel 3. The upper surface of the drawer panel 3 is fixedly connected with a fuse unit nameplate 4, and the fuse unit nameplate 4 is fixedly connected with a factory code nameplate 5 on one side. Meanwhile, the lower surface of the drawer panel 3 is fixedly connected with a combination and division indication 6, and the drawer panel 3 is fixedly connected with a combination and division button assembly 7 below the combination and division indication 6. Moreover, an operation procedure 8 is fixedly connected between the combination and division indication 6 and the combination and division button assembly 7. The operation procedure 8 is fixedly connected with a handle 9 for pulling the panel and the insulating support 1 on one side.

[0029] The bottom surface of the insulating support 1 is fixedly connected with guide strips 10 on both sides through screws. The guide strips 10 are provided with guide grooves 11 for slidingly connecting with the external installation box. The openings of the two guide grooves 11 are located on the side away from each other of the two guide strips 10. In addition, the bottom surface of the insulating support 1 is fixedly connected with a grounding copper sheet 12. The bottom surface of the insulating support 1 is fixedly connected with two interposed baffle plates 13 between the two guide strips 10. The arrangement direction of the two baffle plates 13 is the same as the sliding direction of the insulating support 1. The drawer panel 3 is provided with a rotating hole 14, and the drawer panel 3 is fixedly connected with a dust cover 15 for closing or opening the rotating hole 14 at the rotating hole 14. Meanwhile, the drawer panel 3 is rotatably connected with a transmission screw rod 16 at the rotating hole 14.

[0030] One end of the transmission screw rod 16 penetrates the two baffle plates 13 in sequence, and the surface of the end of the transmission screw rod 16 to the baffle plate 13 close to the end of the transmission screw rod 16 is provided with a threaded groove 17. In use, the transmission screw rod 16 can be threadedly connected with the external installation box through the threaded groove 17, and the insulating support 1 can be opened or closed by rotating the transmission screw rod through a tool. In addition, a plurality of first gaskets 18 are axially sleeved on the upper surface of the transmission screw rod 16, and the side surface of the first gasket 18 abuts against the corresponding baffle plate 13. Meanwhile, a screw rod spring 19 is axially sleeved on the surface of the part of the transmission screw rod 16 between the two baffle plates 13, and the two ends of the screw rod spring 19 respectively abut against the position corresponding first gasket 18. Meanwhile, a shaft pin is penetrated on the transmission screw rod 16, and the shaft pin abuts against the first gasket 18 on the baffle plate 13 close to the drawer panel 3.

[0031] Referring to Figure 1 , the top surface of the insulating support 1 is fixedly connected with a support plate 20 through a nut. The surface of the support plate 20 is fixedly connected with a secondary plug-in component 21. The two sides of the secondary plug-in component 21 are fixedly connected with guide rods 22 through screws. In use, the guide rods 22 extend into the corresponding grooves on the external installation box, and the secondary plug-in component 21 is inserted into the corresponding clamping grooves on the external installation box.

[0032] Referring to Figure 1 、 Figure 2 ,Figure 3 The first partition plate, the second partition plate and the third partition plate are fixedly connected in the insulation support 1. The first partition plate, the second partition plate and the third partition plate cooperate to divide the interior of the insulation support 1 into a switch cavity 23, a mounting cavity 24, a control cavity 25 and a driving cavity 26. The closing and opening device comprises an auxiliary switch 27 fixedly connected in the switch cavity 23, the auxiliary switch 27 being connected with an electric contact plate 28 through a shaft pin, and the driving cavity 26 being fixedly connected with a permanent magnet assembly 29, the electric contact plate 28 being fixedly connected with the permanent magnet assembly 29 after penetrating through the first partition plate, so that the auxiliary switch 27 can provide power support for the permanent magnet assembly 29.

[0033] With reference to Figure 4 , Figure 5 The permanent magnet assembly 29 comprises a closing and opening rod 30 penetrating through the second partition plate and extending into the control cavity 25, and a debugging buffer 31 is axially sleeved on the closing and opening rod 30 in the control cavity 25, so as to reduce the abrasion of the closing and opening rod 30 during operation. The end of the closing and opening rod 30 is connected with a double rocker assembly. The double rocker assembly comprises a support frame 32 fixedly connected with the insulation support 1, the cross section of the support frame 32 being in the shape of a "T", a plug pin being inserted into the end of the support frame 32, two short connecting plates 33 being rotatably connected at the two ends of the plug pin and located at the two sides of the support frame 32, a connecting rod 34 being rotatably connected with the end of the plug pin away from the support frame 32 and located between the two short connecting plates 33, and the end of the connecting rod 34 being connected with the closing and opening rod 30 through a plug pin. Two long connecting plates 35 are rotatably connected on the plug pin connecting the connecting rod 34 and the short connecting plate 33, and the long connecting plates 35 are located between the connecting rod 34 and the short connecting plate 33. Two fixed rods 36 are fixedly connected between the two long connecting plates 35, and the fixed rods 36 are used to improve the rigidity between the two long connecting plates 35.

[0034] With reference to Figure 2 , Figure 4 , Figure 5 The insulation support 1 is provided with a positioning groove 37 on the side wall in the control cavity 25, and a positioning plate 38 is slidably connected in the positioning groove 37. The positioning plate 38 is fixed to the bottom surface of the insulation support 1 through bolts. In addition, the positioning plate 38 is provided with a positioning hole 39, and an insulator 40 is inserted into the positioning hole 39 and can slide in the positioning hole 39. One end of the insulator 40 is rotatably connected with the end of the long connecting plate 35 away from the connecting rod 34 through a plug pin, and the other end of the insulator 40 is fixedly connected with a plug connector 41. The vacuum protection device comprises a vacuum arc-extinguishing device 42 fixedly connected in the control cavity 25, the end of the vacuum arc-extinguishing device 42 away from the insulator 40 being fixedly connected with an electric outlet 43, and the end of the vacuum arc-extinguishing device 42 close to the insulator 40 being provided with a plug hole, the plug connector 41 on the insulator 40 being capable of extending into the plug hole, so as to realize the butt joint of the insulator 40 and the vacuum arc-extinguishing device 42.

[0035] With reference to Figure 4 , Figure 6 , the insulating support 1 is fixedly connected with two fixed columns 44 in the installation cavity 24, the fuse protection device comprises a fuse 45 fixedly connected on the fixed columns 44 by screws, and the fuse 45 is located between the two fixed columns 44, wherein the fixed column 44 away from the permanent magnet assembly 29 is fixedly connected with a connecting copper plate 46, at the same time, one end of the connecting copper plate 46 is fixedly connected with an incoming head 47 by screws. And, the side of the fuse 45 away from the connecting copper plate 46 is fixedly connected with a contact 49 through a soft connecting piece 48, at the same time, the insulating support 1 is fixedly connected with an adapter column 50 in the installation cavity 24, the adapter column 50 is provided with an adapter slot 51, and the installation cavity 24 and the control cavity 25 are communicated through the adapter slot 51, and the contact 49 extends into the adapter slot 51 and slides along the inner wall of the adapter slot 51.

[0036] With reference to Figure 4 , Figure 5 , Figure 6 , the thermal sensitive device comprises a shape memory alloy 52 sleeved on the plug-in head 41 and a soft metal sheet 53 fixedly connected on the surface of the shape memory alloy 52, and the plug-in head 41 is sleeved with a clamping plate 54 on one side of the soft metal sheet 53, and the plug-in head 41 is sleeved with a second gasket 55 on one side of the shape memory alloy 52, so as to fix the shape memory alloy 52 and the soft metal sheet 53 on the plug-in head 41. In addition, the end of the shape memory alloy 52 and the soft metal sheet 53 is provided with a connecting head 56, and the connecting head 56 extends into the adapter slot 51 and abuts against the contact 49, so as to make the circuit of the incoming head 47 and the outgoing head 43 communicated. In addition, the shape memory alloy 52 is provided with double strokes, which drives the soft metal sheet 53 to bend after being heated, and makes the connecting head 56 and the contact 49 disengage, and when the temperature decreases, it drives the soft metal sheet 53 to restore.

[0037] With reference to Figure 3 , Figure 6 , the positioning plate 38 is provided with a driving slot 57, wherein the bottom of the driving slot 57 is fixedly connected with a pressure sensor 58, and the pressure sensor 58 is electrically connected with the auxiliary switch 27. At the same time, the driving slot 57 is slidably connected with a trigger plate 59 made of rubber, and the trigger plate 59 abuts against the inner wall of the driving slot 57, one side of the trigger plate 59 is fixedly connected with a pressing plate 60, and the pressing plate 60 is located below the shape memory alloy 52, so as to push the trigger plate 59 to slide towards the pressure sensor 58 after the shape memory alloy 52 is deformed by heat, and thus trigger the auxiliary switch 27, With reference to Figure 6The insulating support 1 is provided with a limiting groove 61 in the installation cavity 24, and the sidewall of the adapter column 50 is provided with a through groove and the adapter groove 51 is communicated with the limiting groove 61. The limiting groove 61 is slidably connected with a wedge-shaped block 62 made of insulating ceramic material, the wedge-shaped block 62 can pass through the opening and extend into the adapter groove 51, and the small head end of the wedge-shaped block 62 is arranged close to the contact 49 and the connecting head 56, and the sidewall of the contact 49 and the connecting head 56 is provided with an arc-shaped groove 63. In addition, the groove bottom of the limiting groove 61 is provided with a clamping hole 64, and the bottom surface of the wedge-shaped block 62 is provided with a clamping groove 65, and the trigger plate 59 is fixedly connected with a clamping block 66 which passes through the clamping hole 64 and extends into the clamping groove 65. The sidewall of the limiting groove 61 away from the adapter column 50 is fixedly connected with a trigger spring 67, and the end of the trigger spring 67 is fixedly connected with the surface of the wedge-shaped block 62. When the clamping block 66 extends into the clamping groove 65, the trigger spring 67 is in a compressed state. When the clamping block 66 is disengaged from the clamping groove 65, the small head end of the wedge-shaped block 62 abuts against the inner wall of the arc-shaped groove 63 on the contact 49 and the connecting head 56, and the contact 49 and the connecting head 56 are separated.

[0038] The insulating support 1 is fixedly connected with an inclined block 68 in the installation cavity 24, the inclined block 68 is located between the adapter column 50 and the fixed column 44, and the inclined surface of the inclined block 68 is arranged close to the wedge-shaped block 62. In addition, the inclined surface of the inclined block 68 is fixedly connected with a strip-shaped block 69, and the bottom surface of the wedge-shaped block 62 is provided with a strip-shaped groove 70. The trigger spring 67 drives the wedge-shaped block 62 to slide along the inclined surface of the inclined block 68, and the strip-shaped groove 70 is butt-jointed with the strip-shaped block 69, so as to increase the distance between the connecting head 56 and the contact 49, and avoid the wedge-shaped block 62 from sliding and causing the contact 49 to fall off.

[0039] Referring to Figure 6 , Figure 7 , Figure 8 The insulating support 1 is fixedly connected with an annular mounting plate 71 on the top surface of the control cavity 25, and the mounting plate 71 is provided with a cavity. In addition, the insulating support 1 is fixedly connected with a gas tank 72 in the control cavity 25, the gas tank 72 is filled with compressed inert gas, and the gas tank 72 is communicated with the cavity in the mounting plate 71 through a pipeline. The mounting plate 71 is fixedly connected with a nozzle 73 on both sides of the connecting head 56, the inner wall of the nozzle 73 is fixedly connected with a rubber ring 74, the connecting head 56 is fixedly connected with a connecting plate 75, the connecting plate 75 is fixedly connected with a plug 76, and the plug 76 is inserted into the nozzle 73. When the temperature in the control cavity 25 rises and the shape memory alloy 52 deforms, the shape memory alloy 52 drives the plug 76 to pull out of the nozzle 73, so that the inert gas in the gas tank 72 is sprayed out of the nozzle 73. In addition, the rubber ring 74 abuts against the surface of the plug 76, so as to preliminarily fix the positions of the connecting plate 75 and the connecting head 56, and avoid the connecting head 56 from being in poor contact with the contact 49 during use.

[0040] The implementation principle of the embodiment of the application is as follows: in a normal state, the soft metal sheet 53 abuts against the contact 49 through the connecting head 56, and the circuit is in communication; the opening and closing device drives the opening and closing rod 30 through the auxiliary switch 27, drives the double rocker assembly (including the support frame 32, the short connecting plate 33, the connecting rod 34 and the long connecting plate 35) to move, and makes the insulator 40 inserted into the insertion hole of the vacuum arc extinguisher 42, thereby maintaining the stable operation of the circuit.

[0041] When a circuit fault occurs, the temperature in the control cavity 25 rises, the shape memory alloy 52 is deformed by heat, and the soft metal sheet 53 is bent. The shape memory alloy 52 pushes the trigger plate 59 to slide in the driving groove 57, the clamping block 66 on the trigger plate 59 is separated from the clamping groove 65 of the wedge-shaped block 62. The trigger spring 67 is released, the wedge-shaped block 62 slides along the inclined block 68, the first block 69 is clamped with the second block 69, the wedge-shaped block 62 pushes the contact 49 to slide away from the connecting head 56, and the connecting head 56 is disconnected from the contact 49, thereby cutting off the circuit.

[0042] At the same time, the trigger plate 59 abuts against the pressure sensor 58 at the bottom of the driving groove 57, the pressure sensor 58 sends a signal to drive the auxiliary switch 27 to operate, drives the opening and closing device to act (the opening and closing rod 30 slides, the double rocker assembly is linked), and separates the insulator 40 from the vacuum arc extinguisher 42, thereby strengthening the circuit disconnection.

[0043] The deformation of the shape memory alloy 52 also makes the plug 76 pulled out of the nozzle 73, the inert gas in the gas tank 72 is sprayed out through the nozzle 73, the arc is suppressed, and the safety is improved.

[0044] In addition, the overload current causes the vacuum arc extinguisher 42 to act, and the insulator 40 is automatically separated from the insertion hole through the double rocker assembly, thereby realizing arc extinguishing and circuit disconnection.

[0045] If the overload is accompanied by temperature rise, the shape memory alloy 52 deforms to accelerate the above-mentioned overheat protection process. The short-circuit current causes the fuse 45 to melt, the contact 49 slides in the switching groove 51, and is separated from the connecting head 56, thereby directly disconnecting the circuit. The wedge-shaped block 62 keeps the contact 49 separated from the connecting head 56 under the action of the trigger spring 67, thereby preventing misconnection.

[0046] At the same time, after the overheat or short circuit triggers, the pressure sensor 58 ensures the synchronous action of the opening and closing device through the auxiliary switch 27, thereby realizing a multiple disconnection mechanism; and the inert gas system enhances the arc extinguishing effect when overheating. Finally, the circuit can be disconnected in time and reliably under the faults of overload, short circuit, overheat and the like, thereby ensuring the safe and stable operation of the low-voltage single-phase circuit.

[0047] The embodiments of the present application are preferred embodiments of the present application, and are not intended to limit the protection scope of the present application, wherein the same parts are denoted by the same reference numerals. Therefore, any equivalent changes made according to the structure, shape and principle of the present application should be covered within the protection scope of the present application.

Claims

1. A low-voltage single-phase circuit breaker, characterized in that: Includes an insulating support (1), which is provided with a vacuum protection device for overload protection, a fuse protection device for short circuit protection, a circuit breaker for connecting and disconnecting circuits, and a thermistor for overheat protection. The thermal device includes: A shape memory alloy (52) is disposed on the opening and closing device. The shape memory alloy (52) is provided with a soft metal sheet (53), which is used to connect the circuit. A trigger plate (59) is disposed on an insulating bracket (1). The trigger plate (59) abuts against a shape memory alloy (52). The shape memory alloy (52) controls the trigger plate (59) to slide on the insulating bracket (1). A wedge block (62) is set on an insulating bracket (1). The wedge block (62) is engaged with a trigger plate (59). A trigger spring (67) is connected to the wedge block (62). The trigger spring (67) abuts against the insulating bracket (1). The fuse protection device includes a contact (49), which is slidably disposed with respect to the insulating support (1); A connector (56) is provided on the shape memory alloy (52) and the soft metal sheet (53), and the connector (56) abuts against the contact (49); When the shape memory alloy (52) is heated, the trigger spring (67) is activated, and the trigger spring (67) drives the wedge block (62) to disconnect the connector (56) from the contact (49).

2. A low-voltage single-phase circuit breaker according to claim 1, characterized in that: The opening and closing device includes a permanent magnet assembly (29), a dual rocker assembly, and an auxiliary switch (27); The permanent magnet assembly (29) includes a closing / opening gate arm (30), which is connected to a double rocker assembly, and the double rocker assembly is connected to an insulator (40). The auxiliary switch (27) is used to drive the closing and opening lever (30) to slide, and the double rocker assembly controls the connection or disconnection of the insulator (40) with the vacuum protection circuit breaker; The soft metal sheet (53) and shape memory alloy (52) are connected to the insulator (40).

3. A low-voltage single-phase circuit breaker according to claim 2, characterized in that: The insulating bracket (1) has a drive groove (57), the trigger plate (59) slides in the drive groove (57), and a pressure sensor (58) is provided at the bottom of the drive groove (57). The pressure sensor (58) is electrically connected to the auxiliary switch (27). When the shape memory alloy (52) is heated, it drives the trigger plate (59) to contact the pressure sensor (58), and the pressure sensor (58) drives the auxiliary switch (27) to run.

4. A low-voltage single-phase circuit breaker according to claim 1, characterized in that: The wedge plate has a slot (65), and the trigger plate (59) is provided with a block (66) that extends into the slot (65). When the shape memory alloy (52) is heated, it drives the block (66) to extend out of the slot (65).

5. A low-voltage single-phase circuit breaker according to claim 4, characterized in that: The insulating bracket (1) is provided with a ramp block (68), the ramp block (68) is provided with a first strip block (69), the wedge plate is provided with a second strip block (69), the trigger spring (67) drives the first strip block (69) to slide along the ramp block (68) and engage with the second strip block (69), and the wedge block (62) pushes the contact (49) to slide away from the connector (56).

6. A low-voltage single-phase circuit breaker according to claim 2, characterized in that: The dual rocker assembly includes a support frame (32), on both sides of the support frame (32) are rotatably provided with short connecting plates (33), the ends of the two short connecting plates (33) are rotatably connected by a connecting rod (34), a long connecting plate (35) is rotatably provided on the side of the short connecting rod (34), and the end of the long connecting plate (35) is rotatably connected to an insulator (40).

7. A low-voltage single-phase circuit breaker according to claim 6, characterized in that: The vacuum protection device includes a vacuum arc extinguisher (42), which has a plug hole, and the insulator (40) is inserted into the plug hole.

8. A low-voltage single-phase circuit breaker according to claim 1, characterized in that: The connector (56) is provided with a plug (76), the plug (76) is inserted into the nozzle (73), the nozzle (73) is connected to a gas tank (72) through a pipe, and the gas tank (72) is filled with inert gas; A rubber ring (74) is provided at the connection between the nozzle (73) and the plug (76), and the rubber ring (74) abuts against the surface of the plug (76).

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