Thermal electromagnetic system of miniature circuit breaker

Abstract

The utility model discloses a thermal electromagnetic system of a miniature circuit breaker. The thermal electromagnetic system comprises a coil, a bimetal frame, a contact seat and a moving contact. The moving contact is provided with a hook part which is bent towards the bimetal frame, and the bimetal frame is provided with an arc striking sheet which extends towards the hook part. Through the synergistic effect of the hook part which is bent towards one side of the double-metal frame on the moving contact and the arc striking sheet which extends towards the hook part on the double-metal frame, the arc can be effectively led into the arc extinguish chamber below the double-metal frame. Due to the improvement, the residence time of an electric arc at the contact is greatly shortened, and the burning loss degree of the moving contact is remarkably reduced, so that the service life of the circuit breaker is prolonged, the fault risk caused by burning loss of the contact is reduced, the reliability and stability of the whole circuit breaker are improved, and the service life of the circuit breaker is prolonged. And overload and short-circuit protection can be continuously and effectively carried out on lines and electrical equipment in a long-term use process.

Description

TECHNICAL FIELD

[0001] The utility model relates to circuit breaker technical field, concretely is a kind of thermal electromagnetic system of small circuit breaker. BACKGROUND

[0002] Small circuit breaker as the protection electrical apparatus installed in terminal distribution line, in the occasion of alternating current 50 / 60Hz, rated voltage does not exceed 230V, rated current does not exceed 40A, for the overload and short-circuit protection of line and electrical equipment plays a vital role.It is generally composed of thermal electromagnetic system, conducting system, arc extinguishing shield system, operating mechanism etc., wherein thermal electromagnetic system as the key component of electrical switch overcurrent and short-circuit protection, usually by upper connecting sheet, double gold frame, double gold, coil, contact seat, moving contact etc.

[0003] In the breaking operation of small circuit breaker, often face some problems to be solved.Currently, in the breaking process of circuit breaker, there is excessive current limiting and excessive arc time.Due to excessive arc time, it can cause serious burning of moving contact, which not only affects the service life of circuit breaker, but also can reduce the reliability of its protection performance.

[0004] The arc extinguishing process of circuit breaker includes arc jump, arc induction and arc extinguishing.Three important stages.In this process, the arc is smoothly introduced into the arc extinguishing chamber, and the arc moves smoothly in the arc extinguishing chamber, which is extremely critical to improve the arc extinguishing effect.However, the existing small circuit breaker has deficiencies in this regard, and it is difficult to efficiently introduce the arc into the arc extinguishing chamber, resulting in excessive arc residence time at the contact, which further aggravates the contact burning condition, and it is also difficult to effectively control the current limiting size.

[0005] In summary, in order to improve the performance of small circuit breaker, especially in the aspect of arc extinguishing, an innovative design is urgently needed to improve these problems existing in the current breaking process, to ensure that small circuit breaker can operate more stably and reliably, to meet the growing demand for power protection. INVENTION CONTENTS

[0006] The utility model provides a kind of thermal electromagnetic system of small circuit breaker for the deficiency in background art.

[0007] The technical scheme adopted by the utility model is: a kind of thermal electromagnetic system of small circuit breaker, including coil, double gold frame, contact seat and moving contact, the moving contact has the hook portion bending to the side of double gold frame on, the double gold frame has the arc induction sheet extending to the hook portion on.

[0008] The further setting of the application is that the arc induction sheet extends in the extension area of the tip of hook portion.

[0009] The application further provides that the inclination angle of the extension region is 15-25 degrees.

[0010] The application further provides that the coil has a connecting section one and a connecting section two at two ends, and the included angle a between the connecting section one and the connecting section two and the side surface of the coil is 95-120 degrees.

[0011] The application further provides that the connecting section one is connected with the movable contact through a soft connection, and the soft connection is provided with an insulating sleeve.

[0012] The application further provides that the double-gold frame comprises a lower sheet, an upper sheet, a connecting sheet and a bending transition sheet between the lower sheet and the upper sheet, and the lower sheet, the upper sheet, the connecting sheet and the bending transition sheet are bent from a single copper sheet.

[0013] The application further provides that the connecting section two is connected with a copper sheet, and the other end of the copper sheet is electrically connected with the connecting sheet.

[0014] The application further provides that the connecting sheet is connected with a wiring sheet through a soft connection.

[0015] The application has the following beneficial effects:

[0016] Firstly, in terms of arc extinguishing performance, the arc can be effectively introduced into the arc extinguishing chamber below the double-gold frame through the cooperation of the hook part on the movable contact which is bent to the double-gold frame side and the arc leading sheet which extends to the hook part. This improvement greatly shortens the residence time of the arc at the contact, significantly reduces the burning loss of the movable contact, prolongs the service life of the circuit breaker, reduces the risk of failure caused by contact burning, improves the reliability and stability of the entire circuit breaker, and ensures that the circuit breaker can continuously and effectively protect the line and electrical equipment from overload and short circuit during long-term use.

[0017] Secondly, in terms of current limiting effect, since the movement path of the arc is better controlled, the adverse effects of the arc on the circuit are reduced, the current limiting of the circuit breaker during the breaking process is more reasonable, the impact and damage of excessive current limiting on the circuit system are effectively avoided, the safe operation of the electrical equipment connected therewith is ensured, and the stable operation state of the entire power distribution network is maintained.

[0018] Thirdly, the design of the application optimizes the arc extinguishing process and improves the arc extinguishing efficiency, which not only helps to improve the performance of the small circuit breaker itself, but also to a certain extent, reduces the safety hazards such as fire that may be caused by the arc not being extinguished in time, and has a positive significance for protecting the safety of personnel and property and the safety of the environment where the electrical equipment is located.

[0019] In summary, the thermal electromagnetic system of the miniature circuit breaker of the application brings obvious improvement and promotion in arc extinguishing, current limiting and safety guarantee and other key aspects, has high practical value and broad application prospect, and can well meet the requirements of modern power systems on efficient, stable and safe performance of miniature circuit breakers.

[0020] In addition to the purposes, features and advantages described above, the utility model has other purposes, features and advantages. BRIEF DESCRIPTION OF DRAWINGS

[0021] Fig. 1 It is a structural schematic diagram of the utility model.

[0022] Fig. 2 It is a schematic diagram of the coil.

[0023] Fig. 3 It is a schematic diagram of the thermal electromagnetic system and the circuit breaker shell.

[0024] Figs. 1-3 Medium: 1, coil; 2, double gold frame; 3, contact seat; 4, moving contact; 5, hook part; 6, arc leading piece; 7, connection section one; 8, connection section two; 9, soft connection; 10, insulating sleeve; 11, lower piece; 12, upper piece; 13, connecting piece; 14, bent transition piece; 15, copper piece; 16, wiring piece. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the application.

[0026] It should be noted that if the embodiments of the utility model have involved directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition and the like between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications also change accordingly.

[0027] The utility model provides a kind of thermal electromagnetic system of miniature circuit breaker.

[0028] In the embodiment, referring to Figs. 1-3 The thermal electromagnetic system of the miniature circuit breaker, including coil 1, double gold frame 2, contact seat 3 and moving contact 4, the moving contact has the hook part 5 that is bent to the side of double gold frame, and the double gold frame has the arc leading piece 6 that extends to the hook part.

[0029] In the technical solution, the structure design of the hook part of the moving contact and the arc introduction piece of the double-gold frame provides a guide path for the arc introduction into the arc extinguishing chamber, effectively shortens the arc contact time, reduces the burning loss of the moving contact, improves the arc extinguishing efficiency, improves the breaking performance of the circuit breaker, and solves the fault hidden danger of excessive current limiting caused by the arc problem.

[0030] Specifically, the arc introduction piece extends in the extension area of the tip of the hook part.

[0031] In this embodiment, the extension area specifically refers to the dashed line area in Fig. 1 The specific range is the tangent extension outside the hook part. By limiting the extension of the arc introduction piece in the tip of the hook part, the arc introduction position is further precisely positioned, the cooperative arc introduction effect between the hook part and the arc introduction piece is enhanced, the arc can be more quickly and accurately introduced into the arc extinguishing chamber, the reliability and stability of arc extinguishing are improved, and the damage of the arc to the contacts and other components in unintended positions is reduced.

[0032] Specifically, the inclination angle of the extension area is 15-25°.

[0033] In this embodiment, the inclination angle of the extension area is controlled to be 15-25°, which optimizes the angle condition of arc introduction, so that the arc can follow a more reasonable motion trajectory when entering the arc extinguishing chamber, reduces the arc motion resistance, improves the arc introduction speed, thereby further shortens the arc burning time, improves the arc extinguishing effect, and helps to reduce the impact and wear on the internal structure of the circuit breaker caused by abnormal arc motion.

[0034] Specifically, the coil has a connecting section one 7 and a connecting section two 8 at both ends, and the included angle a between the connecting section one and the connecting section two and the side surface of the coil is 95-120°.

[0035] In this embodiment, the connecting section one and the connecting section two with a specific angle range (95-120°) are designed to have an angle with the side surface of the coil, which optimizes the connection layout of the coil and other components, so that the coil can more effectively act on the moving contact when generating electromagnetic force, ensures the timeliness and accuracy of the moving contact action under overload or short circuit conditions, and is conducive to the electromagnetic force conduction and balance inside the entire thermoelectric system, improves the response speed and protection capability of the circuit breaker to fault current.

[0036] Specifically, the connecting section one is connected to the moving contact through a soft connection 9, and the soft connection is provided with an insulating sleeve 10.

[0037] In the embodiment, the connecting section one is connected with the movable contact through a soft connection and an insulating sleeve, the soft connection ensures reliable electrical connection between the movable contact and the coil during the movement of the movable contact, and the flexible property of the soft connection can adapt to the movement change of the movable contact, thereby reducing the damage risk of the connecting part caused by mechanical stress; the insulating sleeve effectively prevents the electric leakage, improves the electrical safety of the system, guarantees the stable operation of the circuit breaker in the complex electrical environment, and avoids the safety accidents caused by the electric leakage and the interference to other electrical equipment.

[0038] Specifically, the double-gold frame comprises a lower sheet 11, an upper sheet 12, a connecting sheet 13, and a bending transition sheet 14 between the lower sheet and the upper sheet, and the lower sheet, the upper sheet, the connecting sheet, and the bending transition sheet are bent from a single copper sheet.

[0039] In the embodiment, the double-gold frame is an integrated structure bent from a single copper sheet, thereby reducing the connecting points between the components, reducing the contact resistance, and improving the electrical conductivity.

[0040] Specifically, the connecting section two is connected with a copper sheet 15, and the other end of the copper sheet 15 is electrically connected with the connecting sheet.

[0041] In the embodiment, the connecting section two is connected with the copper sheet and electrically connected with the connecting sheet of the double-gold frame, thereby constructing a stable current conduction path and making the electrical signal transmission between the coil and the double-gold frame more smooth.

[0042] Specifically, the connecting sheet is connected with a wiring sheet 16 through a soft connection.

[0043] In the embodiment, the connecting sheet is connected with the wiring sheet through the soft connection, thereby facilitating the connection with the external circuit, and the flexible property of the soft connection can buffer the mechanical stress of the external circuit on the internal thermoelectric system of the small circuit breaker, thereby avoiding the connection loosening or damage caused by the pulling or vibration of the external circuit.

[0044] Note for all technicians: although the utility model has been described according to the above specific embodiments, the utility model idea is not limited to the utility model, and any modification using the utility model idea will be included in the patent protection range.

Claims

1. A thermo-electromagnetic system of a miniature circuit breaker comprising a coil, a double gold frame, a contact seat and a movable contact, characterized in that: The moving contact has a hook part bending to one side of the double gold frame, and the double gold frame has an arc leading part extending to the hook part.

2. A thermal electromagnetic system of a miniature circuit breaker according to claim 1, characterized in that: The arc leading part extends in the extension area of the tip of the hook part.

3. A thermal electromagnetic system of a miniature circuit breaker according to claim 2, characterized in that: The inclination angle of the extension area is 15-25°.

4. The thermal electromagnetic system of a miniature circuit breaker according to claim 1, characterized in that: The coil has a connecting section one and a connecting section two at both ends, and the angle a between the connecting section one and the connecting section two and the side of the coil is 95-120°.

5. A thermal electromagnetic system of a miniature circuit breaker according to claim 4, characterized in that: The connecting section one is connected with the moving contact through a soft connection, and the soft connection is sleeved with an insulating sleeve.

6. A thermal electromagnetic system of a miniature circuit breaker according to claim 5, characterized in that: The double gold frame comprises a lower sheet, an upper sheet, a connecting sheet and a bending transition sheet between the lower sheet and the upper sheet, and the lower sheet, the upper sheet, the connecting sheet and the bending transition sheet are bent from a single copper sheet.

7. A thermal electromagnetic system of a miniature circuit breaker according to claim 6, characterized in that: The connecting section two is connected with a copper sheet, and the other end of the copper sheet is electrically connected with the connecting sheet.

8. A thermal electromagnetic system of a miniature circuit breaker according to claim 7, characterized in that: The connecting sheet is connected with a wiring sheet through a soft connection.

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