A modular single-break structure molded case circuit breaker

Abstract

The utility model provides a module formula single breakpoint structure plastic shell circuit breaker, including circuit breaker shell, the inside installation of circuit breaker shell has module upper cover and module lower cover, module upper cover and module lower cover are fixed as a rectangular frame through screw and nut, three groups of installation clamping slots are set up in the rectangular frame, the inside still is equipped with arc extinguishing chamber of rectangular frame, every installation clamping slot inside all is equipped with static contact and moving contact, every installation clamping slot all with arc extinguishing chamber corresponds, realizes the technical effect of improving breaking capacity, protection internal element and adaptation automation assembly.

Description

Technical Field

[0001] This utility model relates to a modular single-break structure molded case circuit breaker. Background Technology

[0002] Molded case circuit breakers (MCCBs) are a common type of low-voltage electrical appliance in power systems, primarily used for circuit connection, disconnection, and short-circuit protection. With the increasing demands on circuit breaker performance in power systems, particularly on breaking capacity and safety, single-break MCCBs have gained widespread application in low-voltage power distribution systems due to their simple structure and low cost.

[0003] Currently, most single-break molded case circuit breakers on the market adopt an open arc-extinguishing structure. For example, CN112885674A discloses a closed arc-extinguishing chamber and circuit breaker for a single-break molded case circuit breaker, which includes a shell, an end cover, and multiple arc-extinguishing grids. The shell and end cover are assembled to form a closed chamber, and the arc-extinguishing grids are installed inside the chamber. The end cover has an opening for air to escape when the circuit breaker breaks. Although this structure has a simple assembly process, the arc-extinguishing chamber is highly open, making it difficult for pressure to accumulate during the circuit breaker breaking process, thus affecting the arc-extinguishing efficiency.

[0004] Existing single-break molded case circuit breakers have the following technical problems: First, the arc-extinguishing chamber of traditional single-break molded case circuit breakers is highly open, leading to difficulties in pressure accumulation, limited cooling efficiency, and unsatisfactory airflow control, making it difficult for the ultimate breaking capacity of frames of 250A and below to exceed 50kA; Second, during breaking capacity tests, the arc is easily splashed onto the electronic circuit board or internal wires, causing high-temperature burns, resulting in the failure of subsequent overload trip performance verification; In addition, the internal components of existing single-break molded case circuit breakers are relatively scattered and numerous, which is not suitable for the requirements of modern industrial automated assembly lines, affecting production efficiency and product consistency.

[0005] Therefore, there is an urgent need for a modular single-break molded case circuit breaker with a compact structure, high arc extinguishing efficiency, and suitable for automated production to solve the above-mentioned technical problems. Utility Model Content

[0006] The purpose of this utility model is to overcome the shortcomings of the prior art and provide a modular single-break molded case circuit breaker, achieving the technical effects of improved breaking capacity, protection of internal components, and adaptability to automated assembly. This purpose of this utility model is achieved as follows:

[0007] This utility model proposes a modular single-break structure molded case circuit breaker, including a circuit breaker housing. Inside the circuit breaker housing, a module upper cover and a module lower cover are installed. The module upper cover and module lower cover are fixed into a rectangular frame by screws and nuts. Three sets of mounting slots are provided inside the rectangular frame. An arc-extinguishing chamber is also installed inside the rectangular frame. Each mounting slot has a stationary contact and a moving contact installed inside, and each mounting slot corresponds to an arc-extinguishing chamber.

[0008] Furthermore, the circuit breaker housing is connected to the rectangular frame by screws.

[0009] Furthermore, the moving contact has at least two bending angles, the directions of which are opposite.

[0010] Furthermore, the bending angle of the module cover matches that of the moving contact.

[0011] Furthermore, an arc-extinguishing channel is distributed on one side of the arc-extinguishing chamber. The arc-extinguishing channel is located on one side of the rectangular frame and is opposite to the arc-extinguishing chamber. An exhaust port is correspondingly distributed on the upper side of each mounting slot. The exhaust port is located on one side of the rectangular frame.

[0012] Compared with the prior art, the beneficial effects of this utility model are: through the design of the rectangular frame, the direction and speed of gas flow can be controlled more precisely, and the electric arc can be transferred quickly and smoothly from the contact gap to the arc extinguishing chamber, avoiding the electric arc from staying in the contact area for a long time and burning, thus improving the electrical life of the circuit breaker.

[0013] The modular packaging design of the rectangular frame increases interphase insulation capability.

[0014] The rectangular frame design allows for modular assembly, adapting to modern industrial automated production lines and enabling modular replacement. This makes maintenance operations faster and more economical, with a compact structure and a simpler and more efficient assembly process. Attached Figure Description

[0015] Figure 1 This is an exploded schematic diagram of a modular single-break molded case circuit breaker.

[0016] Figure 2 This is a schematic diagram of the internal structure of the module cover of a modular single-break molded case circuit breaker.

[0017] Figure 3 This is a three-dimensional structural diagram of the lower cover of a modular single-break molded case circuit breaker.

[0018] Figure 4 This is a schematic diagram of the internal structure of the moving contact of a modular single-break molded case circuit breaker.

[0019] In the diagram: 1. Module top cover, 2. Screw, 3. Arc extinguishing chamber, 4. Module bottom cover, 5. Nut, 6. Stationary contact, 7. Moving contact, 8. Mounting slot, 9. Exhaust port. Detailed Implementation

[0020] To enhance understanding of this utility model, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. These embodiments are only used to explain the present utility model and do not constitute a limitation on the scope of protection of the present utility model.

[0021] Please refer to Figure 1-4 This utility model proposes a modular single-break structure molded case circuit breaker, including a circuit breaker housing. Inside the circuit breaker housing, a module upper cover 1 and a module lower cover 4 are installed. The module upper cover 1 and the module lower cover 4 are fixed into a rectangular frame by screws 2 and nuts 5. Three sets of mounting slots 8 are provided inside the rectangular frame. An arc-extinguishing chamber 3 is also installed inside the rectangular frame. Each mounting slot 8 is equipped with a stationary contact 6 and a moving contact 7, and each mounting slot 8 corresponds to the arc-extinguishing chamber 3.

[0022] In this embodiment, the circuit breaker housing and the rectangular frame are connected by screws 2. This connection method makes the entire circuit breaker structure more robust and facilitates disassembly when maintenance or replacement of internal parts is required. The screw connection method also improves the overall stability of the circuit breaker and reduces the loosening problem caused by vibration during long-term use.

[0023] In this embodiment, the moving contact 7 has at least two bending angles, which are opposite in direction. Specifically, one end of the moving contact 7 is connected to the operating mechanism of the circuit breaker, and the middle part is provided with a first bending angle, which is 120 degrees relative to the front, so that the moving contact 7 bends upward; the end near the stationary contact 6 is provided with a second bending angle, which is opposite in direction to the first bending angle and is 150 degrees relative to the front, so that the end of the moving contact 7 can make good contact with the stationary contact 6. This design allows the moving contact 7 to quickly move away from the stationary contact 6 when disconnected, increasing the disconnection distance and improving the disconnection speed and safety of the circuit breaker.

[0024] In this embodiment, the bending angle of the module cover 1 and the moving contact 7 are matched. The module cover 1 is designed with a structure that matches the bending angle of the moving contact 7. When the circuit breaker is in the closed state, the bent part of the moving contact 7 is located in the corresponding groove of the module cover 1, so that the moving contact 7 can be stably held in the predetermined position. When the circuit breaker is open, the bending design of the moving contact 7 and the matching structure of the module cover 1 work together to ensure that the moving contact 7 can quickly leave the stationary contact 6 and maintain a safe distance. This matching design not only improves the operational reliability of the circuit breaker, but also extends the service life of the contacts.

[0025] In this embodiment, an arc-extinguishing channel is distributed on one side of the arc-extinguishing chamber 3. The arc-extinguishing channel is opened on one side of the rectangular frame and is opposite to the arc-extinguishing chamber 3. When the circuit breaker is disconnected, the electric arc generated between the contacts is guided into the arc-extinguishing chamber 3. Each mounting slot 8 has a corresponding exhaust port 9 on its upper side. The exhaust port 9 is opened on one side of the rectangular frame and then discharged through the arc-extinguishing channel. The design of the arc-extinguishing channel enables the electric arc to be cooled and divided quickly, effectively eliminating the damage of the electric arc to the internal structure of the circuit breaker. The relative arrangement of the arc-extinguishing channel and the arc-extinguishing chamber 3 forms a complete arc-extinguishing system, which greatly improves the arc-extinguishing capability and safety performance of the circuit breaker.

[0026] In practical operation, when an overload or short circuit occurs, the circuit breaker's operating mechanism drives the moving contact 7 to rotate, separating it from the stationary contact 6 and generating an electric arc. The arc is immediately guided into the arc-extinguishing chamber 3, where it is divided and cooled by the arc-extinguishing plates. The remaining high-temperature gas and arc are discharged through the arc-extinguishing channel. Due to the bending angle design of the moving contact 7, the contact separation speed is faster and the separation distance is greater, effectively reducing the arc duration and improving the circuit breaker's breaking capacity. This single-break molded case circuit breaker has an additional module upper cover 1 and module lower cover 4 inside, and a modular packaging design. Each phase inside the module lower cover 4 is separated by a mold cavity, increasing the phase-to-phase insulation capacity. During assembly, the two upper covers and the internal moving contact 7 and stationary contact 6 can be assembled first, and the closed module upper cover 1 and module lower cover 4 can be installed into the circuit breaker housing. The installation steps are simplified, making replacement convenient and reducing the complexity of installation. This further increases modularity and assembly efficiency.

[0027] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this utility model without departing from the spirit and scope of the technical solutions of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A modular single-break molded case circuit breaker, characterized in that, The circuit breaker includes a circuit breaker housing, inside which a module upper cover and a module lower cover are installed. The module upper cover and module lower cover are fixed into a rectangular frame by screws and nuts. Three sets of mounting slots are provided inside the rectangular frame. An arc-extinguishing chamber is also installed inside the rectangular frame. Each mounting slot has a stationary contact and a moving contact installed inside, and each mounting slot corresponds to an arc-extinguishing chamber.

2. A modular single-break molded case circuit breaker according to claim 1, characterized in that, The circuit breaker housing is connected to the rectangular frame by screws.

3. A modular single-break molded case circuit breaker according to claim 2, characterized in that, The moving contact has at least two bending angles, and the directions of the bending angles are opposite.

4. A modular single-break molded case circuit breaker according to claim 3, characterized in that, The bending angle of the module cover matches that of the moving contact.

5. A modular single-break molded case circuit breaker according to claim 4, characterized in that, An arc-extinguishing channel is distributed on one side of the arc-extinguishing chamber. The arc-extinguishing channel is opened on one side of the rectangular frame and is opposite to the arc-extinguishing chamber. An exhaust port is correspondingly distributed on the upper side of each mounting slot. The exhaust port is opened on one side of the rectangular frame.

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