A high-current electromagnetic system for miniature circuit breakers

Abstract

This utility model discloses a high-current electromagnetic system for a miniature circuit breaker, comprising a magnetic system body, which includes an electromagnetic coil assembly, and a magnetic yoke is fitted around the electromagnetic coil assembly. After the magnetic yoke is fitted around the electromagnetic coil assembly, only one side of the electromagnetic wires of the electromagnetic coil assembly is exposed. A base plate is provided below the magnetic yoke; by raising the base plate, its upper surface is brought closer to the electromagnetic wires of the electromagnetic coil assembly. In summary, by using the magnetic yoke fitted around the electromagnetic coil assembly, the magnetic yoke can form closed magnetic circuits in both the XY and ZY planes, generating the maximum attraction force with the fewest spiral coil turns, thus improving the short-circuit breaking capacity.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, specifically to a high-current electromagnetic system for a miniature circuit breaker. Background Technology

[0002] Currently, the magnetic systems of miniature circuit breakers in the industry generally adopt the following configuration: a helical coil with moving and stationary iron core assemblies inside. To concentrate the magnetic field, a magnetic yoke is usually placed around the helical coil to reduce magnetic leakage. When a short-circuit current passes through the helical coil, a large electromagnetic field is generated, causing the moving and stationary iron cores to attract and push out the push rod, thus tripping the circuit breaker. However, in products with larger rated currents, due to size limitations, the number of turns in the helical coil is usually small, and the magnetic yoke cannot form a closed loop. This results in insufficient electromagnetic field strength, leading to a slower attraction speed of the moving and stationary iron cores when a short-circuit current passes through, thus affecting the product's opening speed. Furthermore, it lacks pressure relief capability and suffers from the problem of poor heat dissipation generated by the electric arc. Utility Model Content

[0003] The purpose of this invention is to provide a high-current electromagnetic system for a miniature circuit breaker to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a high-current electromagnetic system for a miniature circuit breaker, comprising a magnetic system body, wherein the magnetic system body includes an electromagnetic coil assembly, and a magnetic yoke is fitted around the electromagnetic coil assembly; wherein, after the magnetic yoke is fitted around the electromagnetic coil assembly, only one side of the electromagnetic wires of the electromagnetic coil assembly is exposed; a base plate is also provided below the magnetic yoke, and by raising the base plate, the upper surface of the base plate is brought close to the electromagnetic wires of the electromagnetic coil assembly.

[0005] As a preferred technical solution of this utility model: the base plate is connected to the bottom of the magnetic yoke through a connecting part, and the connecting part is arc-shaped.

[0006] As a preferred technical solution of this utility model: when the electromagnetic coil assembly is installed on the magnetic yoke, the width of the base plate is greater than the maximum outer diameter of the electromagnetic wire.

[0007] As a preferred technical solution of this utility model: the base plate is further provided with a first pressure relief groove, and the groove opening direction of the first pressure relief groove is parallel to the magnetic field line direction of the electromagnetic coil assembly.

[0008] As a preferred technical solution of this utility model: the side of the magnetic yoke away from the electromagnetic coil assembly is also provided with a heat dissipation hole, and the groove direction of the heat dissipation hole is parallel to the magnetic field line direction of the electromagnetic coil assembly.

[0009] As a preferred technical solution of this utility model: the heat dissipation hole is opened on the baffle, and the baffle is movably connected to the back of the magnetic yoke.

[0010] As a preferred technical solution of this utility model: the heat dissipation holes are arranged in groups of three, and are divided into three groups and opened on the baffle from top to bottom.

[0011] As a preferred technical solution of this utility model: both sides of the baffle are provided with support ribs, and the support ribs are adapted to the connecting groove provided on the back of the magnetic yoke to improve the stability of the baffle after it is connected to the magnetic yoke.

[0012] As a preferred technical solution of this utility model: an arc-guiding plate is provided below the base plate, and a second pressure relief groove is provided on the arc-guiding plate, and the groove opening direction of the second pressure relief groove is parallel to the magnetic field line direction of the electromagnetic coil assembly.

[0013] As a preferred technical solution of this utility model: when the arc-inducing plate is installed below the base plate, the first pressure relief groove and the second pressure relief groove are staggered.

[0014] The beneficial effects of this utility model using the above technical solution are as follows: By using a magnetic yoke fitted outside the electromagnetic coil assembly, the magnetic yoke can form closed magnetic circuits in both the XY and ZY planes, generating the maximum attraction force with the fewest spiral coil turns, thus improving the short-circuit breaking capacity. In particular, the two pressure relief grooves not only dissipate heat from the fire extinguishing chamber, but the staggered arrangement of the first and second pressure relief grooves also provides a stepped pressure relief effect, further preventing excessive pressure from breaking down the casing; at the same time, the heat dissipation holes can dissipate heat inside the magnetic yoke, reducing the heat generated by the eddy current effect while ensuring the magnetic field is concentrated. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the main structure of this utility model;

[0016] Figure 2 This is a front view of the main structure of this utility model;

[0017] Figure 3 This is an exploded view of the main structure of this utility model;

[0018] Figure 4 This is a side view of the magnetic yoke of this utility model.

[0019] Figure 5 This is a schematic diagram of the structure of the present invention after it is installed inside the circuit breaker housing.

[0020] In the figure: 1. Shell; 2. Arc-extinguishing chamber; 3. Magnetic system body; 30. Electromagnetic coil assembly; 31. Magnetic yoke; 32. Arc-starting plate; 33. Base plate; 34. First pressure relief groove; 35. Connecting groove; 36. Heat dissipation hole; 37. Support rib; 38. Baffle; 39. Second pressure relief groove; 310. Connecting part; 4. Moving contact. Detailed Implementation

[0021] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model. In the description of this utility model, it should be understood that the terms "upper," "lower," "front," "upper surface," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this utility model.

[0022] Please see Figure 1-5 The present invention provides an embodiment of a high-current electromagnetic system for a miniature circuit breaker, comprising a magnetic system body 3. Specifically, the magnetic system body 3 is installed inside the housing 1, and the stationary contact portion of the magnetic system body 3 extends above the arc-extinguishing chamber 2.

[0023] Furthermore, the magnetic system body 3 includes an electromagnetic coil assembly 30, and a magnetic yoke 31 is fitted around the outside of the electromagnetic coil assembly 30. After the magnetic yoke 31 is fitted onto the electromagnetic coil assembly 30, only one side of the electromagnetic wire of the electromagnetic coil assembly 30 is exposed. Thus, the magnetic yoke 31 can surround all sides of the electromagnetic coil assembly 30 except for one exposed side, thus enabling the magnetic yoke 31 to form closed magnetic circuits in both the XY and ZY planes, reducing magnetic leakage, ensuring magnetic force concentration in the XY plane direction, generating the maximum attraction force with the fewest spiral coil turns, enhancing the electromagnetic force generated during short circuits, improving the attraction capacity of the electromagnetic coil assembly 30 to the moving contact 4, and thereby improving the breaking capacity of the circuit breaker.

[0024] Furthermore, a base plate 33 is provided below the magnetic yoke 31. By raising the base plate 33, the upper surface of the base plate 33 is brought closer to the electromagnetic wires of the electromagnetic coil assembly 30. Figure 4As shown, the base plate 33 is connected to the bottom of the magnetic yoke 31 via a connecting part 310, and the connecting part 310 is arc-shaped to facilitate the upward lifting of the base plate 33. Thus, in the event of a short circuit, the base plate 33 can be positioned below the electromagnetic wire to further reduce magnetic leakage and ensure magnetic force concentration in the XY plane direction, thereby enhancing the electromagnetic attraction generated by the electromagnetic coil assembly 30.

[0025] Meanwhile, when the electromagnetic coil assembly 30 is installed on the magnetic yoke 31, the width of the base plate 33 is greater than the maximum outer diameter of the electromagnetic wire, so that the base plate 33 is at least flush with the outermost edge of the electromagnetic wire. This setting not only has a certain effect on reducing magnetic leakage, but is also the core means to achieve a significant reduction in magnetic leakage. It makes the magnetic yoke form a completely enclosed closed magnetic path. Relying on this completely enclosed magnetic circuit structure, the magnetic leakage phenomenon is weakened to the greatest extent.

[0026] like Figure 3 As shown, the base plate 33 is also provided with a first pressure relief groove 34, and the groove opening direction of the first pressure relief groove 34 is parallel to the magnetic field line direction of the electromagnetic coil assembly 30, which plays the role of releasing air pressure from the electric arc and preventing excessive pressure from breaking through the shell 1.

[0027] At the same time, such as Figure 1 and Figure 2 As shown, an arc-inducing plate 32 is also provided below the base plate 33, and a second pressure relief groove 39 is provided on the arc-inducing plate 32. The groove opening direction of the second pressure relief groove 39 is parallel to the magnetic field line direction of the electromagnetic coil assembly 30. Furthermore, when the arc-inducing plate 32 is installed below the base plate 33, the first pressure relief groove 34 and the second pressure relief groove 39 are staggered. Thus, the arrangement of the two pressure relief grooves not only allows for heat dissipation of the fire extinguishing chamber, but the staggered arrangement of the first pressure relief groove 34 and the second pressure relief groove 39 also provides a stepped pressure relief effect, thereby further preventing excessive pressure from puncturing the casing 1.

[0028] Based on the above solutions, such as Figure 3 As shown, the magnetic yoke 31 has heat dissipation holes 36 on the side away from the electromagnetic coil assembly 30, and the slot direction of the heat dissipation holes 36 is parallel to the direction of the magnetic field lines of the electromagnetic coil assembly 30. The heat dissipation holes 36 can also dissipate heat inside the magnetic yoke 31. Furthermore, the heat dissipation holes 36 are arranged in groups of three, from top to bottom, on the baffle 38. Based on this, the heat generation caused by eddy current effects can be reduced while ensuring the magnetic field is concentrated.

[0029] To facilitate the machining of the heat dissipation holes 36 on the magnetic yoke 31, the heat dissipation holes 36 are formed on the baffle 38, and the baffle 38 is movably connected to the back of the magnetic yoke 31. This allows the magnetic yoke 31 and the heat dissipation holes 36 to be manufactured and machined independently, reducing the machining difficulty of the magnetic yoke 31. The first pressure relief groove 34, the heat dissipation hole 36, and the second pressure relief groove 39 are all oblong grooves, and their major axes are parallel to the direction of the magnetic field lines.

[0030] Specifically, both sides of the baffle 38 are provided with support ribs 37, which are adapted to connect with the connecting grooves 35 on the back of the magnetic yoke 31 to improve the stability of the connection between the baffle 38 and the magnetic yoke 31. The support ribs 37 are installed in the connecting grooves 35 of the magnetic yoke 31, so that the magnetic yoke 31 forms a closed magnetic circuit in the ZY plane, reducing magnetic leakage and ensuring magnetic force concentration in the ZY plane.

[0031] In summary, this device can form closed magnetic circuits in both the XY and ZY planes, achieving the maximum attraction force with the fewest spiral coil turns, while also reducing heat generation, lowering temperature rise, and guiding the arc evenly into the arc-extinguishing chamber, thereby improving the product's opening speed and short-circuit breaking capacity.

[0032] The embodiments of this utility model have been described in detail above with reference to the accompanying drawings, but this utility model is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of this utility model, and these variations still fall within the protection scope of this utility model.

Claims

1. A high-current electromagnetic system for a miniature circuit breaker, comprising a magnetic system body (3), characterized in that: The magnetic system body (3) includes an electromagnetic coil assembly (30), and a magnetic yoke (31) is fitted on the outside of the electromagnetic coil assembly (30); wherein, after the magnetic yoke (31) is fitted on the electromagnetic coil assembly (30), only one side of the electromagnetic wire of the electromagnetic coil assembly (30) is exposed. A base plate (33) is also provided below the magnetic yoke (31). By raising the base plate (33), the upper surface of the base plate (33) is brought close to the electromagnetic wire of the electromagnetic coil assembly (30). The base plate (33) is also provided with a first pressure relief groove (34), and the groove opening direction of the first pressure relief groove (34) is parallel to the magnetic field line direction of the electromagnetic coil assembly (30); Below the base plate (33), there is also an arc-guiding plate (32), and the arc-guiding plate (32) is provided with a second pressure relief groove (39), and the groove direction of the second pressure relief groove (39) is parallel to the magnetic field line direction of the electromagnetic coil assembly (30); When the arc-inducing plate (32) is installed below the base plate (33), the first pressure relief groove (34) and the second pressure relief groove (39) are offset from each other.

2. The high-current electromagnetic system for a miniature circuit breaker according to claim 1, characterized in that: The base plate (33) is connected to the bottom of the magnetic yoke (31) through a connecting part (310), and the connecting part (310) is arc-shaped.

3. The high-current electromagnetic system for a miniature circuit breaker according to claim 2, characterized in that: When the electromagnetic coil assembly (30) is mounted on the magnetic yoke (31), and the width of the base plate (33) is greater than the maximum outer diameter of the electromagnetic wire.

4. A high-current electromagnetic system for a miniature circuit breaker according to any one of claims 1-3, characterized in that: The magnetic yoke (31) is provided with a heat dissipation hole (36) on the side away from the electromagnetic coil assembly (30), and the slot direction of the heat dissipation hole (36) is parallel to the magnetic field line direction of the electromagnetic coil assembly (30).

5. The high-current electromagnetic system for a miniature circuit breaker according to claim 4, characterized in that: The heat dissipation hole (36) is opened on the baffle (38), and the baffle (38) is movably connected to the back of the magnetic yoke (31).

6. The high-current electromagnetic system for a miniature circuit breaker according to claim 5, characterized in that: The heat dissipation holes (36) are arranged in groups of three, and are divided into three groups from top to bottom on the baffle (38).

7. The high-current electromagnetic system for a miniature circuit breaker according to claim 5, characterized in that: Both sides of the baffle (38) are provided with support ribs (37), and the support ribs (37) are adapted to the connecting groove (35) provided on the back of the magnetic yoke (31) to improve the stability of the baffle (38) after it is connected to the magnetic yoke (31).

Images