Miniature circuit breaker with controlled temperature rise

Abstract

The utility model discloses a control temperature rise's miniature circuit breaker, control temperature rise's miniature circuit breaker includes the casing, is equipped with static contact, movable contact in the casing, static contact extends and is equipped with the heat conduction part, the back of movable contact is equipped with the let -by slot, the heat conduction part, let -by slot solidly is equipped with the heat conduction board, the both sides of heat conduction board are equipped with a plurality of radiating fins, the casing is equipped with the limiting portion of protruding, is used for limiting movable contact's movable range. Through heat conduction part, heat conduction board and radiating fin promote static contact and movable contact in contact and break the instantaneous heat conduction and the dissipation efficiency of break, realize air convection heat dissipation in combination with first vent, second vent and heat dissipation chamber, reduce the temperature rise of contact area, restrain the increase of contact resistance and sintering risk, guarantee the stable break function, the protruding portion is equipped with zero arc -flash shan piece effective barrier and extinguish arc residual particle, improve electrical safety, improve equipment operation reliability and service life.

Description

Technical Field

[0001] This utility model relates to the field of circuit breaker technology, and in particular to a miniature circuit breaker for controlling temperature rise. Background Technology

[0002] Miniature circuit breakers are important control and protection devices in low-voltage power distribution systems. Miniature circuit breakers are equipped with moving and stationary contacts. When the circuit breaker interrupts the current, the moving and stationary contacts open, generating an electric arc. The electric arc needs to be quickly transferred to the arc-extinguishing chamber to protect the contact material, prevent excessive burning, and extinguish the arc.

[0003] In existing technologies, the moving and stationary contacts are prone to high temperatures due to electric arcing during repeated breaking processes. This leads to carbide deposition and metal particle residue on the contact surface, resulting in a continuous increase in contact resistance and exacerbating local temperature rise. This creates a vicious cycle of increasing temperature and contact resistance, which can easily cause high-temperature sintering of the contacts, ultimately impairing the breaking function and causing product failure. To address these issues, this application provides a corresponding technical solution. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of traditional miniature circuit breaker designs and provide a product that reduces temperature rise, improves breaking performance, and extends service life.

[0005] To solve the above problems, the present invention adopts the following technical solution.

[0006] A miniature circuit breaker for controlling temperature rise includes a housing, within which are a stationary contact and a moving contact. The stationary contact extends with a heat-conducting portion, and the back of the moving contact has a clearance groove. A heat-conducting plate is fixed to the heat-conducting portion and the clearance groove. Several heat dissipation fins are provided on both sides of the heat-conducting plate. The housing has a protruding limiting portion for restricting the range of motion of the moving contact. The limiting portion has several equally spaced first ventilation holes. The inner sides of the housing have protrusions, which are located on one side of the limiting portion. Several equally spaced second ventilation holes are provided in the protrusions. Stacked anti-arc fins are provided in the protrusions. A heat dissipation chamber is provided below one end of the housing.

[0007] Preferably, the housing is further provided with an arc-extinguishing chamber and an electromagnetic trip unit. The housing is provided with terminals at both ends. One end of the electromagnetic trip unit is electrically connected to the stationary contact, and the other end is electrically connected to one of the terminals. The arc-extinguishing chamber is located directly in front of the heat-conducting plate of the heat-conducting part.

[0008] Preferably, the heat-conducting part and the relief groove are provided with at least one rivet post, the heat-conducting plate is provided with a through hole for the rivet post to pass through, one end of the through hole is provided with a countersunk hole, and the rivet post is pressed into the countersunk hole by a riveting process.

[0009] Preferably, the housing has an inclined guide surface located at the outlet of the arc-extinguishing chamber, and the guide surface extends toward the heat dissipation chamber.

[0010] Preferably, the heat dissipation chamber has multiple heat dissipation holes on one side, and the heat dissipation chamber has a first extension and a second extension. The first extension is adjacent to the guide surface, and the first extension and the second extension are arranged alternately to form a tortuous air passage.

[0011] Preferably, the protrusion is provided with a cavity for accommodating the zero-flying arc plate, and the cavity is provided with fixing grooves on the front, back, left and right sides.

[0012] Preferably, the zero-flying arc strip has grooves at both ends, the grooves have a plurality of equally spaced pressure relief holes, the sidewalls of the zero-flying arc strip have a fixing part that is embedded in the fixing groove, and the fixing part is fixed in the fixing groove by fastening screws.

[0013] Beneficial effects:

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0015] (1) This utility model significantly improves the heat conduction and dissipation efficiency of the stationary and moving contacts in the contact and conduction state and at the moment of disconnection by setting up the heat conduction part, heat conduction plate and heat dissipation fins. Combined with the first ventilation hole, second ventilation hole and heat dissipation chamber set on the housing, it effectively promotes forced convection heat dissipation formed by temperature difference in the housing, significantly reduces the operating temperature rise of the contact area, thereby suppressing the increase in contact resistance and the risk of contact sintering caused by heat accumulation, and ensuring long-term reliability of the disconnection function.

[0016] (2) In this utility model, the zero-arc fin stacked inside the protrusion can effectively block and quickly extinguish the arc residue that may escape through the second ventilation hole when the moving and stationary contacts are broken, limit its diffusion range, and improve the electrical safety performance of the product. Attached Figure Description

[0017] Figure 1 This is a front view of a miniature circuit breaker for controlling temperature rise according to the present invention.

[0018] Figure 2 This is a side cross-sectional view of a miniature circuit breaker for controlling temperature rise according to the present invention.

[0019] Figure 3 This utility model Figure 2 A partially enlarged view (A) of a miniature circuit breaker for controlling temperature rise;

[0020] Figure 4 This is an exploded structural diagram of a miniature circuit breaker for controlling temperature rise according to the present invention.

[0021] The correspondence between the labels and component names in the attached figures is as follows:

[0022] Reference numerals: 1. Housing; 2. Stationary contact; 3. Moving contact; 4. Heat-conducting plate; 5. Arc-extinguishing fin; 6. Arc-extinguishing chamber; 7. Electromagnetic trip unit; 8. Terminal block; 9. Rivet post; 11. Limiting part; 12. First ventilation hole; 13. Protrusion; 14. Second ventilation hole; 15. Heat dissipation chamber; 16. Guide surface; 131. Cavity; 132. Fixing groove; 151. Heat dissipation hole; 152. First extension; 153. Second extension; 154. Air passage; 21. Heat-conducting part; 31. Relief groove; 41. Heat dissipation fin; 42. Through hole; 43. Countersunk hole; 51. Countersunk groove; 52. Pressure relief hole; 53. Fixing part; 54. Fastening screw. Detailed Implementation

[0023] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] In the description of this utility model, it should be understood that the terms "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They 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. Therefore, they should not be construed as limitations on this utility model.

[0025] In this embodiment of the utility model, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0026] Reference example Figures 1 to 4A miniature circuit breaker for controlling temperature rise includes a housing 1. A stationary contact 2 and a moving contact 3 are disposed within the housing 1. The stationary contact 2 extends with a heat-conducting portion 21. A clearance groove 31 is provided on the back of the moving contact 3. A heat-conducting plate 4 is fixed to the heat-conducting portion 21 and the clearance groove 31. Several heat dissipation fins 41 are provided on both sides of the heat-conducting plate 4. The housing 1 has a protruding limiting portion 11 for limiting the range of motion of the moving contact 3. The limiting portion 11 has several equally spaced first ventilation holes 12. Protrusions 13 are provided on both inner sides of the housing 1 and are disposed on one side of the limiting portion 11. Several equally spaced second ventilation holes 14 are provided within the protrusions 13. The protrusion 13 is provided with stacked zero-arc fins 5, and a heat dissipation chamber 15 is provided at the bottom of one end of the housing 1. Through the arrangement of the heat-conducting part 21, the heat-conducting plate 4 and the heat dissipation fins 41, the heat conduction and dissipation efficiency of the stationary contact 2 and the moving contact 3 in the contact conduction state and at the moment of disconnection is significantly improved. In conjunction with the first ventilation hole 12, the second ventilation hole 14 and the heat dissipation chamber 15 provided on the housing 1, the forced convection heat dissipation formed by the temperature difference in the housing 1 is effectively promoted, the operating temperature rise of the contact area is significantly reduced, thereby suppressing the increase in contact resistance and the risk of contact sintering caused by heat accumulation, and ensuring the long-term reliability of the disconnection function.

[0027] It is worth mentioning that the housing 1 is also equipped with an arc-extinguishing chamber 6 and an electromagnetic trip device 7. The housing 1 has terminals 8 at both ends. One end of the electromagnetic trip device 7 is electrically connected to the stationary contact 2, and the other end is electrically connected to one of the terminals 8. The arc-extinguishing chamber 6 is located in front of the heat-conducting plate 4 of the heat-conducting part 21.

[0028] It is worth mentioning that the heat-conducting part 21 and the relief groove 31 are provided with at least one rivet 9, and the heat-conducting plate 4 is provided with a through hole 42 for the rivet 9 to pass through. One end of the through hole 42 is provided with a countersunk hole 43. The rivet 9 is pressed into the countersunk hole 43 by a riveting process. By riveting the rivet 9, the heat-conducting plate 4 is tightly connected to the heat-conducting part 21 or the relief groove 31, thereby improving the heat conduction efficiency. If it is necessary to further improve the heat conduction efficiency, thermal grease can be applied to the part of the heat-conducting plate 4 that contacts the heat-conducting part 21 or the relief groove 31.

[0029] It is worth mentioning that the housing 1 is provided with an inclined guide surface 16, which is located at the outlet of the arc-extinguishing chamber 6. The guide surface 16 extends toward the heat dissipation chamber 15, and the guide surface 16 guides the hot air into the heat dissipation chamber 15 in an orderly manner.

[0030] It is worth mentioning that a plurality of heat dissipation holes 151 are provided on one side of the heat dissipation chamber 15. The heat dissipation chamber 15 is provided with a first extension 152 and a second extension 153. The first extension 152 is adjacent to the guide surface 16. The first extension 152 and the second extension 153 are arranged in a staggered manner to form a tortuous air passage 154. The hot air is guided in an orderly manner to the second extension 153 through the first extension 152, and then the hot air is transported to the heat dissipation holes 151 by the second extension 153. The tortuous air passage 154 structure makes the hot air flow in the air passage 154 along a predetermined path, ensuring that the hot air enters the heat dissipation holes 151 smoothly. The optimized layout of the air passage 154 improves the airflow organization efficiency, enhances the heat dissipation effect, and reduces the risk of local temperature accumulation.

[0031] It is worth mentioning that the protrusion 13 is provided with a cavity 131 for accommodating the zero-arc strip 5. The cavity 131 is provided with fixing grooves 132 in front, behind, left and right. The zero-arc strip 5 stacked in the protrusion 13 can effectively block and quickly extinguish the arc residue that may escape through the second ventilation hole 14 when the moving and stationary contacts 2 are broken, limit its diffusion range, and improve the electrical safety performance of the product.

[0032] It is worth mentioning that the zero-arc creepage plate 5 has grooves 51 at both ends, and the grooves 51 have several pressure relief holes 52 at equal intervals. The side wall of the zero-arc creepage plate 5 extends to provide a fixing part 53, which is embedded in the fixing groove 132. The fixing part 53 is installed and fixed in the fixing groove 132 by fastening screws 54. The grooves 51 ensure that adjacent zero-arc creepage plates 5 maintain the distance required to extinguish the arc. The pressure relief holes 52 allow the cold air entering from the second through hole 42 to smoothly enter the housing 1, realizing airflow circulation. The fixing groove 132, together with the fixing part 53, ensures that the zero-arc creepage plate 5 is installed in the predetermined position. The limiting part 11 and the protrusion 13 work together to increase the arc creepage distance, improve electrical insulation performance, and enhance overall safety and reliability.

[0033] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present utility model. It should not be construed that the specific implementation of the present utility model is limited to these descriptions. For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present utility model, and all such deductions or substitutions should be considered to fall within the scope of protection defined by the claims submitted by the present utility model.

Claims

1. A miniature circuit breaker for controlling temperature rise, comprising a housing (1), wherein a stationary contact (2) and a moving contact (3) are provided within the housing (1), characterized in that: The stationary contact (2) extends with a heat-conducting part (21), and the back of the moving contact (3) is provided with a relief groove (31). The heat-conducting part (21) and the relief groove (31) are fixed with a heat-conducting plate (4). The heat-conducting plate (4) is provided with several heat dissipation fins (41) on both sides. The housing (1) is provided with a protruding limiting part (11) to limit the range of motion of the moving contact (3). The limiting part (11) is provided with several equally spaced first ventilation holes (12). The inner sides of the housing (1) are provided with protrusions (13) and are located on one side of the limiting part (11). The protrusions (13) are provided with several equally spaced second ventilation holes (14). The protrusions (13) are provided with stacked zero-arc fins (5). A heat dissipation chamber (15) is provided below one end of the housing (1).

2. The miniature circuit breaker for controlling temperature rise according to claim 1, characterized in that: The housing (1) is also provided with an arc-extinguishing chamber (6) and an electromagnetic trip device (7). The housing (1) is provided with terminals (8) at both ends. One end of the electromagnetic trip device (7) is electrically connected to the stationary contact (2), and the other end is electrically connected to one of the terminals (8). The arc-extinguishing chamber (6) is located in front of the heat-conducting plate (4) of the heat-conducting part (21).

3. The miniature circuit breaker for controlling temperature rise according to claim 1, characterized in that: The heat-conducting part (21) and the relief groove (31) are provided with at least one rivet (9). The heat-conducting plate (4) is provided with a through hole (42) through which the rivet (9) passes. One end of the through hole (42) is provided with a countersunk hole (43). The rivet (9) is pressed into the countersunk hole (43) by a riveting process.

4. The miniature circuit breaker for controlling temperature rise according to claim 1, characterized in that: The housing (1) is provided with an inclined guide surface (16) and is located at the outlet of the arc-extinguishing chamber (6), the guide surface (16) extending toward the heat dissipation chamber (15).

5. The miniature circuit breaker for controlling temperature rise according to claim 4, characterized in that: The heat dissipation chamber (15) has a plurality of heat dissipation holes (151) on one side. The heat dissipation chamber (15) has a first extension (152) and a second extension (153). The first extension (152) is adjacent to the guide surface (16). The first extension (152) and the second extension (153) are arranged in a staggered manner to form a tortuous air passage (154).

6. The miniature circuit breaker for controlling temperature rise according to claim 1, characterized in that: The protrusion (13) is provided with a cavity (131) for accommodating the zero-flying arc plate (5), and the cavity (131) is provided with fixing grooves (132) on the front, back, left and right sides.

7. The miniature circuit breaker for controlling temperature rise according to claim 6, characterized in that: The zero-flying arc plate (5) has grooves (51) at both ends, and the grooves (51) have a number of pressure relief holes (52) at equal intervals. The sidewall of the zero-flying arc plate (5) extends to provide a fixing part (53) and is embedded in the fixing groove (132). The fixing part (53) is installed and fixed in the fixing groove (132) by fastening screws (54).

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