A dustproof and convenient-to-disassemble molded case circuit breaker

Abstract

The utility model discloses a dustproof and convenient to dismount plastic shell circuit breaker, its technical scheme main points are including the upper cover, middle cover and base of being connected in order, and the both sides of middle cover are provided with the slot, and the both sides of upper cover are provided with the insert piece of being able to respectively insert two slots, and upper cover is provided with the operating mouth of operating handle's through, and upper cover is provided with a plurality of along upper cover upper edge length direction distribution's hook foot and two along upper cover lower edge length direction distribution and the connecting hole of bolt's through, and the middle cover is provided with a plurality of respectively the hook hole of a plurality of hook foot's through, and the both sides of upper cover all are provided with a plurality of along upper cover side wall length direction distribution's first heat dissipation hole, through with hooking the hook hole and hooking the joint to the position and swing to the position of upper cover and middle cover and make bolt can pass through the connecting hole and spin into middle cover, have solved the problem of the low operation efficiency of upper cover dismounting and easy to enter dust of prior art.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, and more specifically to a dustproof and easy-to-install molded case circuit breaker. Background Technology

[0002] The power distribution system is a crucial link in the power system, directly facing end customers and providing electricity for residential and industrial use. The quality of the power distribution system directly affects the reliability and quality of electricity supply for residents and industries. In low-voltage distribution networks, molded case circuit breakers (MCCBs) are mechanical switching devices capable of connecting, carrying, and breaking current under normal circuit conditions and under specified abnormal circuit conditions (such as short circuits) for a certain period of time. MCBs play a control and protection role in the operation of the power system; therefore, their operation, maintenance, and repair are closely related to the entire power system.

[0003] Molded case circuit breakers (MCCBs) suffer from slow heat dissipation due to their plastic casing, leading to malfunctions. Chinese patent application number 2024109320314 discloses an MCCB comprising a top cover, a middle cover, and a base. While the top cover has a first heat dissipation hole, which addresses some heat dissipation issues, it still has drawbacks. First, dust and impurities in the air can easily fall into the top cover's interior through the first heat dissipation hole and subsequently enter the base through the through-hole in the middle cover. These dust and impurities can interfere with the integrated circuit board inside the base, affecting the normal operation of the MCCB. Second, the top cover and middle cover are fixed together by four geometrically distributed bolts. Disassembly and assembly require rotating a large number of bolts, making the process cumbersome. Furthermore, bolts are prone to being lost after disassembly, affecting the efficiency of subsequent assembly. Utility Model Content

[0004] In view of the shortcomings of the existing technology, the purpose of this utility model is to provide a molded case circuit breaker that prevents dust and impurities from falling into the top cover and makes it easy to disassemble and assemble the top cover and the middle cover.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a dustproof and easy-to-assemble molded case circuit breaker, comprising an upper cover, a middle cover, and a base connected in sequence. The middle cover has slots on both sides, and the upper cover has inserts on both sides that can be inserted into the two slots respectively. The upper cover has an operating port through which an operating handle passes. The upper cover has multiple hooks distributed along the length of the upper edge and two connecting holes distributed along the length of the lower edge for bolts to pass through. The middle cover has multiple hook holes for multiple hooks to pass through. The upper cover has multiple first heat dissipation holes distributed along the length of the sidewall of the upper cover on both sides. By inserting the hooks into the hook holes and swinging the upper cover to a position where it fits against the middle cover, bolts can pass through the connecting holes and be screwed into the middle cover.

[0006] As a further improvement of this utility model, the upper cover is provided with a variable groove located above the operation port. The bottom of the variable groove is provided with a plurality of second heat dissipation holes that can communicate with the inner cavity of the upper cover and are distributed along the edge contour of the bottom of the variable groove. The variable groove is detachably connected to a variable cover that can simultaneously cover all the second heat dissipation holes. The variable cover is provided with a plurality of bendable and deformable buckles that can pass through the second heat dissipation holes.

[0007] As a further improvement of this utility model, two reinforcing ribs are provided on the facing surfaces of the two inserts, both of which are parallel to the width direction of the side wall of the upper cover. The two reinforcing ribs located on the same insert are respectively close to the upper edge and the lower edge of the insert.

[0008] As a further improvement of this utility model, the plurality of the first heat dissipation holes are all located near the upper edge of the top cover.

[0009] As a further improvement of this utility model, there is a gap between the insert and the bottom of the slot to allow air circulation.

[0010] As a further improvement of this utility model, the middle cover is provided with a plurality of third heat dissipation holes arranged side by side, and the height of the plurality of third heat dissipation holes is less than the height of the plurality of hook holes.

[0011] As a further improvement of this utility model, a heat dissipation groove with an inclined bottom surface is provided on the side wall of the base. The width of the inner cavity of the heat dissipation groove gradually changes along the width direction of the side wall. The opening width of the heat dissipation groove facing the middle cover is greater than the thickness of the side wall of the middle cover.

[0012] As a further improvement of this utility model, the base is provided with a plurality of heat dissipation pipes that connect the inner cavity of the base to the outside. The height of the plurality of heat dissipation pipes is lower than the height of the heat dissipation groove, and the ports of the plurality of heat dissipation pipes that are not connected to the base are close to the middle cover.

[0013] As a further improvement of this utility model, a redundant groove communicating with the heat dissipation pipe is provided on the outer wall of the base.

[0014] The beneficial effects of this utility model are as follows: By inserting the hook foot into the hook hole and swinging the top cover to fit with the middle cover, the bolt can pass through the connecting hole and be screwed into the middle cover. Compared with the prior art, this design can reduce the number of connecting holes and the number of bolts required, thereby reducing the operation of rotating the bolts, simplifying the disassembly and assembly steps, reducing the difficulty of disassembly and assembly, and the fewer bolts are easier to store, reducing the possibility of bolt loss, and indirectly improving assembly efficiency. The design of setting the first heat dissipation hole on both sides of the top cover, compared with the prior art design of setting the first heat dissipation hole on the upper surface of the top cover, can effectively prevent dust, impurities and other things from falling into the top cover, effectively ensuring the normal operation of electronic components in the base. Attached Figure Description

[0015] Figure 1 This is a perspective view of the present utility model; Figure 2 for Figure 1 A stereoscopic view from another perspective; Figure 3 for Figure 2 Enlarged view of point A in the middle; Figure 4 for Figure 2 Enlarged view of point B in the middle; Figure 5 This is an exploded view of the present invention; Figure 6 for Figure 5 A state diagram from another perspective; Figure 7 This is a cross-sectional view of the present invention.

[0016] Reference numerals: 1. Top cover; 10. Operating port; 11. Insert; 12. Hook; 13. Connecting hole; 14. First heat dissipation hole; 15. Variable slot; 16. Second heat dissipation hole; 17. Reinforcing rib; 2. Middle cover; 21. Slot; 22. Hook hole; 23. Third heat dissipation hole; 3. Base; 31. Heat dissipation groove; 32. Heat dissipation pipe; 33. Redundancy groove; 4. Variable cover; 41. Clip. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Identical components are indicated by the same reference numerals.

[0018] Reference Figures 1 to 7As shown, a dustproof and easy-to-assemble molded case circuit breaker of this embodiment includes an upper cover 1, a middle cover 2 and a base 3 connected in sequence. The middle cover 2 is provided with slots 21 on both sides, and the upper cover 1 is provided with inserts 11 on both sides that can be inserted into the two slots 21 respectively. The upper cover 1 is provided with an operating port 10 for the operating handle to pass through. Based on the aforementioned prior art, multiple hooks 12 are integrally formed on the upper edge of the upper cover 1 that can fit with the middle cover 2, and the hooks 12 are all L-shaped. Two connecting holes 13 are machined on the surface of the upper cover 1 where the operating opening 10 is machined. The two connecting holes 13 are both near the lower edge and are located at the two apex corners of the upper cover 1. Multiple first heat dissipation holes 14 are machined on the two side walls of the upper cover 1 where the insert 11 is machined, and the middle cover 2 is machined with... During assembly, the upper cover 1 is tilted relative to the middle cover 2 and moved towards the middle cover 2. Then, the hooks 12 are inserted into the hook holes 22 one by one. Subsequently, the upper cover 1 is turned towards the middle cover 2. As the angle between the upper cover 1 and the middle cover 2 gradually decreases, the insert 11 approaches the slot 21 and extends into the slot 21 until the upper cover 1 and the middle cover 2 are in place, the insert 11 is inserted into the slot 21, and the hooks 12 are in contact with the upper inner wall of the hook hole 22. There is a gap in the lower inner wall, and multiple hooks 12 are hooked onto the inner wall of the middle cover 2 to prevent the upper cover 1 from coming off the middle cover 2. The two connecting holes 13 are coaxial with the two threaded holes on the middle cover 1. Finally, bolts are passed through the connecting holes 13 and screwed into the middle cover 1 to fix the upper cover 1 and the middle cover 2 together. During the disassembly process, the two bolts are first unscrewed from the corresponding connecting holes 13, and then an outward force is applied to the lower edge of the upper cover 1 to make the upper cover 1 rotate relative to the middle cover 2. After the insert 11 separates from the slot 21, Pulling the upper cover 1 downwards causes the hook foot 12 to separate from the inner wall of the middle cover 2 and align with the hook hole 22. Continuing to pull the upper cover 1 outwards from the middle cover 2 causes the hook foot 12 to disengage from the corresponding hook hole 22, thus completely separating the middle cover 2 from the upper cover 1. During use, the heat generated inside the base 3 will enter between the middle cover 2 and the upper cover 1 through the hook hole 22 along with the airflow. The hot air moves along the upper inner wall of the upper cover 1 and along the length of the upper inner wall. Finally, the hot air flows through the first heat dissipation holes 14 on both sides of the upper cover 1 to reach the outside. Compared with existing technologies, this design can reduce the number of connecting holes 13 and the number of bolts required, thereby reducing the operation of turning the bolts, simplifying the disassembly and assembly steps, reducing the difficulty of disassembly and assembly, and at the same time, the fewer bolts are easier to store, reducing the possibility of bolt loss, and indirectly improving assembly efficiency. The design of setting the first heat dissipation hole 14 on both sides of the upper cover 1, compared with the existing technology of setting the first heat dissipation hole 14 on the upper surface of the upper cover 1, can effectively prevent dust, impurities and other things from falling into the upper cover 1, and effectively ensure the normal operation of electronic components in the base 3.

[0019] As one specific implementation method of the improvement, refer to Figures 5 to 7 As shown, a variable groove 15 is machined on the surface of the upper cover 1 away from the middle cover 2, located above the operating port 10. The length direction of the variable groove 15 is the same as the width direction of the upper cover 1. The two ends of the variable groove 15 are respectively adjacent to the two side walls of the upper cover 1. Multiple second heat dissipation holes 16 are machined on the bottom of the variable groove 15, connecting the inner cavity of the upper cover 1 with the inner cavity of the variable groove 15. The multiple second heat dissipation holes 16 are distributed along the edge contour of the bottom of the variable groove 15. The variable cover 4 matches the inner cavity of the variable groove 15. Multiple fasteners 41 are provided on the surface of the variable cover 4 facing the bottom of the variable groove 15. The multiple fasteners 41 are all elastic and J-shaped. The number of fasteners 41 is less than or equal to the number of second heat dissipation holes 16, and the second heat dissipation holes 16 can be passed through by the corresponding fasteners 41. During the assembly process, the surface of the variable cover 4 with fasteners 41 is inserted into the variable groove 15. As the variable cover 4 gradually penetrates deeper into the variable groove 15, the hook-shaped ends of multiple buckles 41 extend into the corresponding second heat dissipation holes 16 and slide relative to the port edge of the corresponding second heat dissipation holes 16. The buckles 41 all bend and deform inward toward the variable cover 4 until the variable cover 4 touches the bottom of the variable groove 15. The buckles 41 penetrate the corresponding second heat dissipation holes 16 and the hook-shaped ends of the buckles 41 are located in the inner cavity of the upper cover 1. The buckles 41 return from a bent state to a straight state and the hook-shaped ends of the buckles 41 can touch the inner wall of the upper cover 1. The variable cover 4 is confined within the variable groove 15. During the disassembly process, the upper cover 1 and the middle cover 2 are separated. Then, external force is applied to each buckle 41 to make the buckles 41 bend and the hook-shaped ends retract into the corresponding second heat dissipation holes 16. Finally, the variable cover 4 is removed from the variable groove 15. The removal and installation of the aforementioned variable cover 4 relative to the upper cover 1 can be determined according to the actual situation. For example, in summer, the operating environment temperature of the circuit breaker is high, and the circuit breaker's heat dissipation speed to the outside is slowed down, which may cause the circuit breaker to overheat and burn out. The variable cover 4 can be removed from the variable slot 15, and the hot air dissipated from the base 3 to the space between the upper cover 1 and the middle cover 2 can flow through multiple second heat dissipation holes 16 to reach the outside, improving the heat dissipation speed. In winter, the operating environment temperature of the circuit breaker is low, and the temperature required for the circuit breaker to operate is too low, affecting the operating efficiency. The variable cover 4 can be installed back into the variable slot 15, and multiple second heat dissipation holes 16 are covered, reducing the heat dissipation speed between the upper cover 1 and the middle cover 2, reducing the heat dissipation speed inside the base 3, ensuring the stability of the internal temperature of the base 3 and the stability of the operation of various electronic components. Compared with the existing technology, this design can adaptively adjust according to the ambient temperature of the circuit breaker, which is conducive to the circuit breaker adapting to the operating environment at different temperatures and ensuring the stable operation of the circuit breaker.

[0020] As an improved implementation, during the installation of the upper cover 1 and the middle cover 2, the insert 11 is prone to being squeezed or bumped against the slot 21. The thinness of the insert 11 makes it easy to deform and be damaged, resulting in a looseness between the insert 11 and the slot 21. The upper cover 1 is prone to moving relative to the middle cover 2, which affects the coaxiality of the connecting hole 13 and the threaded hole on the middle cover 2, increasing the difficulty of bolt installation. To solve the above problems, two reinforcing ribs 17 are machined on the facing surfaces of the two inserts 11. The two reinforcing ribs 17 are parallel to the width direction of the side wall of the upper cover 1. The two reinforcing ribs 17 on the same insert 11 are close to the upper edge and lower edge of the insert 11, respectively. This design can improve the structural strength of the insert 11 and its bending resistance under compression, and indirectly improve the compactness of the insert 11 and the slot 21 after they are inserted into place, as well as the accuracy of the installation position of the upper cover 1 relative to the middle cover 2.

[0021] As one specific implementation method of the improvement, refer to Figure 1 and Figure 2 As shown, multiple first heat dissipation holes 14 are all near the upper edge of the upper cover 1. Therefore, the height of the first heat dissipation holes 14 is greater than or equal to the height of the hook hole 22. During the heat dissipation process, the hot air in the base 3 enters the inner cavity of the upper cover 1 through the hook hole 22 and flows through the first heat dissipation holes 14 to reach the outside in a timely manner, reducing the time that the hot air stays in the inner cavity of the upper cover 1 and improving the heat dissipation speed.

[0022] As one specific implementation method of the improvement, refer to Figure 2 and Figure 4 As shown, the slot 21 is further processed along the thickness direction of the side wall to increase the depth of the slot 21. After the insert 11 is inserted into the slot 21, the insert 11 is flush with the side wall surface of the middle cover 2. There is a gap between the insert 11 and the bottom of the slot 21. During the heat exchange process, the hot air in the inner cavity of the upper cover 1 flows upward and through the first heat dissipation hole 14 to reach the outside. At the same time, the outside air flows through the gap between the insert 11 and the slot 21 into the inner cavity of the upper cover 1, forming an effective air flow. Compared with the existing technology that the insert 11 and the slot 21 are fitted together, this design can increase the amount and speed of outside air entering the inner cavity of the upper cover 1, accelerate the heat circulation in the inner cavity of the upper cover 1, and indirectly improve the heat dissipation efficiency of the base 3.

[0023] As an improved specific implementation, because the hook hole 22 is pierced by the hook foot 12, the channel area of ​​the hook hole 22 for airflow from the inside of the base 3 to the upper cover 1 is small, which reduces the heat dissipation efficiency of the base 3. To solve the aforementioned problem, refer to Figure 5 As shown, multiple third heat dissipation holes 23 are machined on the middle cover 2, and the height of the multiple third heat dissipation holes 23 is less than the height of the multiple hook holes 22. This design can increase the amount of airflow between the base 3 and the upper cover 1, thereby accelerating the heat dissipation inside the base 3.

[0024] As one specific implementation method of the improvement, refer to Figure 2 , Figure 3 and Figure 5 As shown, two heat dissipation grooves 31 are obliquely cut on the surfaces where the base 3 and the middle cover 2 fit together, respectively located on the two side walls of the base 3. The cross-section of the inner cavity of the heat dissipation groove 31 along the length of the side wall is triangular. The opening width of the heat dissipation groove 31 on the end face of the side wall is greater than the thickness of the side wall of the middle cover 2. After the middle cover 2 and the base 3 are assembled, the side wall of the middle cover 2 only covers part of the opening of the heat dissipation groove 31. The part of the opening of the heat dissipation groove 31 that is not covered connects the inner cavity of the base 3 with the outside. Compared with the existing technology, this design can realize a certain amount of heat circulation between the base 3 and the outside, and improve the heat dissipation efficiency inside the base 3.

[0025] As one specific implementation method of the improvement, refer to Figure 5 and Figure 6 As shown, the base 3 is provided with multiple heat dissipation pipes 32 that connect the inner cavity of the base 3 to the outside. The height of the multiple heat dissipation pipes 32 is lower than the height of the heat dissipation groove 31. The ports of the multiple heat dissipation pipes 32 that are not connected to the base 3 are all facing and close to the middle cover 2. After the hot air flows upward and flows out of the base 3 through the heat dissipation groove 31, the third heat dissipation hole 23 and the hook hole 22, the outside cold air can flow through the heat dissipation pipes 32 and enter the base 3. While the cold air flows through the heat dissipation pipes 32, it can conduct heat to the heat around the heat dissipation pipes 32, which can effectively reduce the temperature of the area at the height of the heat dissipation pipes 32. Compared with the existing technology that only adds heat dissipation holes to the base 3, the design of the heat dissipation pipes 32 can increase the area through which the cold air flows and effectively reduce the temperature at the lower part of the inner cavity of the base 3.

[0026] As a specific implementation of the improvement, when the circuit breaker is installed inside the cabinet or on the wall, the outer wall of the base 3, to which the heat dissipation pipe 32 is connected, will be in close contact with the external component or the wall. The small gap between the port of the heat dissipation pipe 32 and the external component or the wall affects airflow. To solve the aforementioned problem, refer to Figure 2 and Figure 6 As shown, redundant slots 33 are machined on the outer wall of the base 3. The ports of multiple heat dissipation pipes 32 connected to the base 3 are all located on the bottom of the redundant slots 33. Compared with the prior art, this design can increase the distance between the heat dissipation pipes 32 and the external components or walls, and improve air flow.

[0027] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A dustproof and easy-to-assemble molded case circuit breaker, comprising an upper cover (1), a middle cover (2), and a base (3) connected in sequence, wherein the middle cover (2) has slots (21) on both sides, the upper cover (1) has inserts (11) on both sides that can be inserted into the two slots (21) respectively, and the upper cover (1) has an operating port (10) for the operating handle to pass through, characterized in that: The upper cover (1) is provided with a plurality of hook feet (12) distributed along the length of the upper edge of the upper cover (1) and two connecting holes (13) distributed along the length of the lower edge of the upper cover (1) for bolts to pass through. The middle cover (2) is provided with a plurality of hook holes (22) for a plurality of hook feet (12) to pass through. Both sides of the upper cover (1) are provided with a plurality of first heat dissipation holes (14) distributed along the length of the side wall of the upper cover (1). By inserting the hook feet (12) into the hook holes (22) and swinging the upper cover (1) to a position that fits against the middle cover (2), the bolts can pass through the connecting holes (13) and be screwed into the middle cover (2).

2. The dustproof and easy-to-install molded case circuit breaker according to claim 1, characterized in that: The upper cover (1) is provided with a variable groove (15) located above the operation port (10). The bottom of the variable groove (15) is provided with a plurality of second heat dissipation holes (16) that can communicate with the inner cavity of the upper cover (1) and are distributed along the edge contour of the bottom of the variable groove (15). The variable groove (15) is detachably connected to a variable cover (4) that can cover all the second heat dissipation holes (16) at the same time. The variable cover (4) is provided with a plurality of bendable and deformable buckles (41) that can pass through the second heat dissipation holes (16).

3. A dustproof and easy-to-install molded case circuit breaker according to claim 1 or 2, characterized in that: Two reinforcing ribs (17) are provided on the facing surfaces of the two inserts (11), both of which are parallel to the width direction of the side wall of the upper cover (1). The two reinforcing ribs (17) on the same insert (11) are respectively close to the upper edge and the lower edge of the insert (11).

4. A dustproof and easy-to-install molded case circuit breaker according to claim 1 or 2, characterized in that: Multiple of the first heat dissipation holes (14) are located near the upper edge of the cover (1).

5. A dustproof and easy-to-install molded case circuit breaker according to claim 1 or 2, characterized in that: There is a gap between the insert (11) and the bottom of the slot (21) for air circulation.

6. A dustproof and easy-to-install molded case circuit breaker according to claim 1 or 2, characterized in that: The middle cover (2) is provided with a plurality of third heat dissipation holes (23) arranged side by side, and the height of the plurality of third heat dissipation holes (23) is less than the height of the plurality of hook holes (22).

7. A dustproof and easy-to-install molded case circuit breaker according to claim 1 or 2, characterized in that: The base (3) has a heat dissipation groove (31) with an inclined bottom surface on its side wall. The width of the inner cavity of the heat dissipation groove (31) gradually changes along the width direction of the side wall. The opening width of the heat dissipation groove (31) facing the middle cover (2) is greater than the thickness of the side wall of the middle cover (2).

8. A dustproof and easy-to-install molded case circuit breaker according to claim 7, characterized in that: The base (3) is provided with a plurality of heat dissipation pipes (32) that connect the inner cavity of the base (3) to the outside. The height of the plurality of heat dissipation pipes (32) is lower than the height of the heat dissipation groove (31). The ports of the plurality of heat dissipation pipes (32) that are not connected to the base (3) are close to the middle cover (2).

9. A dustproof and easy-to-install molded case circuit breaker according to claim 8, characterized in that: The base (3) has a redundant slot (33) on its outer wall that communicates with the heat dissipation pipe (32).

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