High-breaking AC / DC universal miniature circuit breaker

Abstract

The invention relates to a high-breaking alternating-current and direct-current universal miniature circuit breaker which comprises a shell, an operating mechanism, a moving contact in linkage fit with the operating mechanism, a static contact matched with the moving contact and an arc extinguish chamber, and a magnetic blow-out mechanism is arranged at the position, corresponding to the moving contact, in the shell. The magnetic blow-out mechanism comprises a U-shaped insulating sleeve arranged in the shell, a U-shaped iron sheet arranged in the U-shaped insulating sleeve and a magnetic conducting piece arranged on the U-shaped insulating sleeve, one side of the U-shaped insulating sleeve is provided with a U-shaped groove for accommodating the moving contact, one end of the magnetic conducting piece is provided with a magnetic conducting part extending into the U-shaped groove, and the other end of the magnetic conducting piece is provided with a magnetic conducting part extending into the U-shaped groove. And two plasma cutting iron sheets are arranged on the outer wall of the U-shaped insulating sleeve corresponding to the two sides of the moving contact. The circuit breaker has the advantages of simple structure, stable and reliable performance, convenience in assembly, long service life, high breaking capacity and alternating current and direct current universality.

Description

Technical Field

[0001] The invention relates to the technical field of circuit breakers, and in particular to a high-breaking AC / DC universal miniature circuit breaker. Background Art

[0002] Miniature circuit breakers, also known as miniature circuit breakers, are suitable for overload and short-circuit protection of AC 50 / 60Hz rated voltage 230 / 400V, rated current not exceeding 125A lines. They can also be used for infrequent line operation conversion under normal circumstances. Miniature circuit breakers are mainly used in various places such as industry, commerce, high-rise and residential buildings. DC miniature circuit breakers should have high breaking capacity in the event of a short circuit and be able to cut off the short-circuit fault current in a timely manner.

[0003] There are significant differences in arc extinguishing performance between small DC circuit breakers and small AC circuit breakers, mainly because of their different working principles and arc characteristics. 1. AC circuit breaker: Each cycle of AC power has a natural zero crossing point, and the arc is easily extinguished at the zero crossing point. Therefore, AC circuit breakers use this characteristic to disconnect the circuit through an arc extinguishing mechanism, making arc extinguishing relatively easy. 2. DC circuit breaker: DC power has no natural zero crossing point, and the DC arc generated is constant. The larger the current and the larger the time constant, the more difficult it is to extinguish the arc. Therefore, DC circuit breakers require additional arc extinguishing devices to enhance the arc extinguishing ability, usually by controlling the switch to cut off the current, which makes the arc extinguishing process more complicated and difficult. However, the arc extinguishing method commonly used by existing DC circuit breakers is to introduce the generated arc into the arc extinguishing chamber through the arc-starting plate for arc extinguishing, and there are defects such as poor arc guidance, long arc extinguishing time, and poor arc extinguishing effect, resulting in weak breaking capacity of the circuit breaker. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a high-breaking AC / DC universal miniature circuit breaker with simple structure, stable and reliable performance, convenient assembly and long service life.

[0005] To achieve the above-mentioned purpose, the present invention adopts a high-breaking AC and DC universal small circuit breaker, including a shell, an operating mechanism, a moving contact linked with the operating mechanism, a static contact matched with the moving contact, and an arc extinguishing chamber. A magnetic blowing mechanism is arranged in the shell corresponding to the moving contact. The magnetic blowing mechanism includes a U-shaped insulating sleeve arranged in the shell, a U-shaped iron sheet arranged in the U-shaped insulating sleeve, and a magnetic conductive part arranged on the U-shaped insulating sleeve. One side of the U-shaped insulating sleeve has a U-shaped groove for accommodating the moving contact, one end of the magnetic conductive part has a magnetic conductive part extending in the U-shaped groove, and two plasma cutting iron sheets are arranged on the outer wall of the U-shaped insulating sleeve corresponding to both sides of the moving contact.

[0006] The beneficial effects of the above structure are: the magnetic blowing mechanism adopts a U-shaped magnetic parallel structure design, and the magnetic field generated by the U-shaped iron sheet cuts the arc during the arc movement. The U-shaped insulating sleeve is cast into an integrated structure using gas-generating materials. The U-shaped insulating sleeve increases inert gas and enhances the cooling effect, while protecting the insulation guarantee of the electrical minimum safety gap of the circuit breaker. The combination of the U-shaped iron sheet and the U-shaped insulating sleeve can play a better gas blowing role, so that a strong gas spray can be formed at the outlet of the U-shaped groove, so that the arc can quickly enter the arc extinguishing chamber, and the arc can be quickly extinguished, which is beneficial to improve the breaking capacity of the circuit breaker. Since the blowing mechanism adopts a non-completely closed U-shaped structure design, plasma cutting iron sheets are arranged on both sides of the U-shaped insulating sleeve, so that the problem of uneven magnetic lines and magnetic fields caused by magnetic leakage can be avoided, and the magnetic conductive part of the magnetic conductive part can increase the magnetic attraction, which can greatly shorten the disconnection time of the circuit breaker at the critical breaking current. Therefore, the small circuit breaker has the advantages of simple structure, stable and reliable performance, convenient assembly, long service life, high breaking, and AC and DC universal.

[0007] In particular, a U-shaped magnetic conductive sheet is provided in the housing and is attached to one side of the static contact, and an insulating spacer is provided in the groove of the U-shaped magnetic conductive sheet. A U-shaped magnetic conductive sheet with a U-shaped integrated structure design is provided on the static contact, and a batch of gas-generating insulating spacers are placed in the middle of the U-shaped magnetic conductive sheet for isolation, and the U-shaped magnetic conductive sheet and the static contact point of the static contact generate a double-circuit magnetic circuit, which can generate more and denser magnetic lines of force, and when encountering accidents such as short circuits, it can generate a greater push-off force, which makes the contacts of the circuit breaker disconnect more quickly and has a stronger breaking capacity.

[0008] In particular, an arc guide piece is provided on the tail of the static contact, and one end of the arc guide piece is bent and extends into the arc extinguishing chamber. When the circuit breaker is disconnected to generate high temperature and high pressure, the arc guide piece can guide the arc to release pressure, ensuring that the burning of the static contact is minimized during the arc re-operation process, and the high-temperature free electron gas is quickly transferred to the arc extinguishing chamber for segmentation, cooling, and arc extinguishing, which is conducive to improving the arc extinguishing performance of the circuit breaker.

[0009] In particular, a gas production plate is provided on both sides of the moving contact corresponding to the moving contact point. During the arc operation, the gas production plate can produce more inert gas, while avoiding the moving contact from being burned by high temperature during the re-breaking process, which is beneficial to prolonging the service life of the contact.

[0010] In particular, the height of the gas production plate is greater than the height of the moving contact, and the moving contact is provided with a rivet connected to the gas production plate. The height of the gas production plate is greater than the height of the moving contact, which can avoid high temperature ablation of the moving contact and is conducive to extending the service life of the moving contact.

[0011] In particular, the movable contact is provided with an arc-shaped clearance groove matched with the magnetic pole on the side facing the U-shaped insulating sleeve. The arc-shaped clearance groove is provided on the movable contact, which can reduce the distance between the magnetic pole and the movable contact, thereby facilitating the enhancement of the magnetic field strength at the movable contact.

[0012] In particular, positioning grooves are respectively provided on both sides of the U-shaped insulating sleeve in the shell, and the U-shaped insulating sleeve is engaged in the positioning grooves, and the U-shaped insulating sleeve and the shell are engaged. The U-shaped insulating sleeve is engaged in the shell, so that the modular assembly of the magnetic blowing mechanism and the shell can be realized, and the assembly is more convenient.

[0013] In particular, two arc isolation plates are arranged at both sides of the housing corresponding to the static contact, and an arc guide channel connected between the U-shaped groove and the arc extinguishing chamber is formed between the two arc isolation plates. The arc guide channel can play a guiding role, ensuring that the gas jet at the outlet of the U-shaped groove can quickly enter the arc extinguishing chamber, thereby facilitating the rapid extinction of the arc. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a cross-sectional view of an embodiment of the present invention.

[0015] Figure 2 This is a diagram of the internal structure of an embodiment of the present invention.

[0016] Figure 3 It is a three-dimensional diagram of the magnetic blowing mechanism according to an embodiment of the present invention.

[0017] Figure 4 It is a three-dimensional diagram of a moving contact according to an embodiment of the present invention. DETAILED DESCRIPTION

[0018] like Figures 1 to 4 As shown, the embodiment of the present invention is a high-breaking AC and DC universal small circuit breaker, including a shell 10, an operating mechanism 11, a moving contact 12 linked with the operating mechanism 11, a static contact 13 matched with the moving contact 12, and an arc extinguishing chamber 14. A magnetic blowing mechanism 20 is arranged in the shell 10 corresponding to the moving contact 12. The magnetic blowing mechanism 20 includes a U-shaped insulating sleeve 21 arranged in the shell 10, a U-shaped iron sheet 22 arranged in the U-shaped insulating sleeve 21, and a magnetic conductive member 23 arranged on the U-shaped insulating sleeve 21. One side of the U-shaped insulating sleeve 21 has a U-shaped groove 211 for accommodating the moving contact 12, and one end of the magnetic conductive member 23 has a magnetic conductive portion 231 extending in the U-shaped groove 211. Two plasma cutting iron sheets 24 are arranged on the outer wall of the U-shaped insulating sleeve 21 corresponding to both sides of the moving contact 12.

[0019] like Figure 1 and 2As shown, the housing 10 is provided with a U-shaped magnetic conductive sheet 15 attached to one side of the static contact 13, and an insulating spacer 16 is provided in the groove 151 of the U-shaped magnetic conductive sheet 15. A U-shaped magnetic conductive sheet with a U-shaped integrated structure design is provided on the static contact, and a batch of gas-generating insulating spacers are placed in the middle of the U-shaped magnetic conductive sheet for isolation, and the U-shaped magnetic conductive sheet and the static contact point of the static contact generate a double-circuit magnetic circuit, which can generate more and finer magnetic lines of force. When encountering accidents such as short circuits, it can generate a greater pushing force, prompting the contacts of the circuit breaker to disconnect more quickly and have a stronger breaking capacity. An arc guide sheet 17 is provided on the tail of the static contact 13, and one end of the arc guide sheet 17 is bent and extends into the arc extinguishing chamber 14. When the circuit breaker is disconnected and high temperature and high pressure are generated, the arc guide can guide the arc to release the pressure, ensuring that the burning of static contacts is minimized during the arc re-operation process. The high-temperature free electron gas is quickly transferred to the arc extinguishing chamber for segmentation, cooling, and arc extinguishing, which is beneficial to improve the arc extinguishing performance of the circuit breaker.

[0020] like Figure 2 and 4 As shown, a gas production plate 18 is respectively provided on both sides of the corresponding moving contact 121 on the moving contact 12. During the arc operation, the gas production plate can produce more inert gas, while avoiding the moving contact from being burned by high temperature during the re-breaking process, which is beneficial to prolonging the service life of the contact. The height of the gas production plate 18 is greater than the height of the moving contact 121, and the moving contact 12 is provided with a rivet 181 connected to the gas production plate 18. The height of the gas production plate is greater than the height of the moving contact, which can avoid high-temperature ablation of the moving contact and is beneficial to prolonging the service life of the moving contact. The moving contact 12 is provided with an arc-shaped clearance groove 122 that matches the magnetic pole 231 on the side facing the U-shaped insulating sleeve 21. The arc-shaped clearance groove is provided on the moving contact, which can reduce the distance between the magnetic pole and the moving contact, thereby helping to enhance the magnetic field strength at the moving contact. Positioning grooves 101 are respectively provided on both sides of the U-shaped insulating sleeve 21 in the shell 10, and the U-shaped insulating sleeve 21 is engaged in the positioning grooves 101, and the U-shaped insulating sleeve 21 and the shell 10 are engaged. The U-shaped insulating sleeve is engaged in the shell, so that the modular assembly of the magnetic blowing mechanism and the shell can be realized, and the assembly is more convenient. Two arc isolation plates 19 are provided on both sides of the static contact 13 in the shell 10, and an arc guide channel 190 connected between the U-shaped groove 211 and the arc extinguishing chamber 14 is formed between the two arc isolation plates 19. The arc guide channel can play a guiding role, ensuring that the gas spray at the outlet of the U-shaped groove can quickly enter the arc extinguishing chamber, which is conducive to the rapid extinction of the arc.

[0021] The magnetic blowing mechanism adopts a U-shaped magnetic parallel structure design. During the arc movement, the magnetic field generated by the U-shaped iron sheet cuts the arc. The U-shaped insulating sleeve is cast into an integrated structure using gas-generating materials. The U-shaped insulating sleeve increases inert gas and enhances the cooling effect, while protecting the insulation guarantee of the electrical minimum safety gap of the circuit breaker. The combination of the U-shaped iron sheet and the U-shaped insulating sleeve can play a better gas blowing role, so that a strong gas spray can be formed at the outlet of the U-shaped groove, so that the arc can quickly enter the arc extinguishing chamber, and the arc can be quickly extinguished, which is beneficial to improve the breaking capacity of the circuit breaker. Since the blowing mechanism adopts a non-completely enclosed U-shaped structure design, plasma cutting iron sheets are arranged on both sides of the U-shaped insulating sleeve, thereby avoiding the problem of uneven magnetic lines and magnetic fields caused by magnetic leakage, and the magnetic conductive part of the magnetic conductive part can increase the magnetic attraction, which can greatly shorten the disconnection time of the circuit breaker at the critical breaking current. Therefore, the small circuit breaker has the advantages of simple structure, stable and reliable performance, convenient assembly, long service life, high breaking, and AC and DC universal.

Claims

1. A high-breakage AC and DC universal miniature circuit breaker, comprising a housing, an operating mechanism, a moving contact coordinated with the operating mechanism, a stationary contact coordinated with the moving contact, and an arc extinguishing chamber, characterized in that: A magnetic blowing mechanism is arranged in the shell at the position corresponding to the moving contact, and the magnetic blowing mechanism includes a U-shaped insulating sleeve arranged in the shell, a U-shaped iron sheet arranged in the U-shaped insulating sleeve, and a magnetic conductive part arranged on the U-shaped insulating sleeve. One side of the U-shaped insulating sleeve has a U-shaped groove for accommodating the moving contact, one end of the magnetic conductive part has a magnetic conductive part extending in the U-shaped groove, and two plasma cutting iron sheets are arranged on the outer wall of the U-shaped insulating sleeve at the two sides corresponding to the moving contact.

2. The high-breakage AC / DC universal miniature circuit breaker according to claim 1 is characterized in that: A U-shaped magnetic conductive sheet attached to one side of the static contact is arranged in the shell, and an insulating isolation sheet is arranged in the groove of the U-shaped magnetic conductive sheet.

3. The high breaking AC / DC universal miniature circuit breaker according to claim 1 or 2, characterized in that: An arc guide piece is arranged on the tail of the static contact, and one end of the arc guide piece is bent and extends into the arc extinguishing chamber.

4. The high-breakage AC / DC universal miniature circuit breaker according to claim 1 or 2, characterized in that: A gas production plate is respectively arranged on both sides of the corresponding moving contact point of the moving contact.

5. The high-breakage AC / DC universal miniature circuit breaker according to claim 4 is characterized in that: The height of the gas production plate is greater than the height of the moving contact, and the moving contact is provided with a rivet connected to the gas production plate.

6. The high breaking AC / DC universal miniature circuit breaker according to claim 1 or 2, characterized in that: An arc-shaped clearance groove matching with the magnetic pole is arranged on the side of the moving contact facing the U-shaped insulating sleeve.

7. The high breaking AC / DC universal miniature circuit breaker according to claim 1 or 2, characterized in that: Positioning grooves are respectively arranged at the two sides of the U-shaped insulating sleeve in the shell, and the U-shaped insulating sleeve is engaged in the positioning grooves to form a snap-fit ​​fit between the U-shaped insulating sleeve and the shell.

8. The high breaking AC / DC universal miniature circuit breaker according to claim 1 or 2, characterized in that: Two arc isolation plates are arranged at both sides of the housing corresponding to the static contact, and an arc guiding channel communicating between the U-shaped groove and the arc extinguishing chamber is formed between the two arc isolation plates.

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