Electromagnetic trip and circuit breaker

Abstract

This application relates to an electromagnetic trip unit and a circuit breaker. The electromagnetic trip unit includes a base, a coil frame, and an iron core. The coil frame is mounted on the base. One of the coil frame and the base has a insertion slot, and the other has an insertion protrusion. The insertion protrusion is interference-fitted with the insertion slot. This confines plastic debris generated during insertion within the insertion slot, preventing it from transferring to the pole face of the iron core or the knife edge face of the yoke. This ensures reliable engagement between the armature and the iron core, maintains a stable tripping current, and prevents malfunctions. The coil frame also has a through hole. One end of the iron core is located within the through hole, and the other end is located in the base and engages with a limiting part for precise positioning of the iron core. This ensures consistent pole face positions. When the armature engages with the iron core, the length of the top part extending out of the housing remains constant, preventing insufficient tripping pressure from affecting the engagement between the iron core and the armature, improving operational reliability, and preventing malfunctions.

Description

Technical Field

[0001] This application relates to the field of electronic control device technology, and in particular to an electromagnetic trip unit and circuit breaker. Background Technology

[0002] In electromagnetic trip units, the base typically has clips that secure the coil holder to the base. Because both the coil holder and the base are made of plastic, the coil holder can scrape against the clips during assembly, generating plastic shavings. These shavings can transfer to the pole face of the iron core or the blade edge of the yoke, causing unreliable engagement between the armature and the iron core. This results in a reduced tripping current and potential malfunction. Furthermore, using clips to secure the coil holder to the base allows for movement of the magnetic circuit, increasing the risk of malfunction. Utility Model Content

[0003] Therefore, it is necessary to provide an electromagnetic trip unit and circuit breaker to improve the reliability of the electromagnetic trip unit's operation and avoid the risk of malfunction.

[0004] In a first aspect, this application provides an electromagnetic trip device, comprising:

[0005] The seat body is provided with a limiting part;

[0006] A coil holder, the coil holder being mounted on the base, one of the coil holder and the base having a insertion groove, the other of the coil holder and the base having a insertion protrusion, the insertion protrusion being disposed within the insertion groove and having an interference fit with the insertion groove, the coil holder also having a through hole extending along a first direction of the base; and

[0007] An iron core, one end of which passes through the through hole and is used to cooperate with the armature, and the other end of which is disposed in the base and cooperates with the limiting part to restrict the movement of the iron core along the first direction.

[0008] In the aforementioned electromagnetic trip unit, during assembly, the insertion protrusion is positioned opposite the opening of the insertion slot. External force is applied to the base and / or coil frame, causing them to approach each other. The insertion protrusion enters the insertion slot. Due to the interference fit between the protrusion and the slot, the protrusion and the slot wall are tightly fitted, forming a relatively enclosed space. This confines plastic debris generated by the friction between the protrusion and the slot wall within this sealed space, preventing it from transferring to the pole face of the iron core or the knife edge of the yoke. This ensures reliable engagement between the armature and the iron core, maintaining a stable tripping current and preventing malfunctions. Furthermore, by providing a limiting part in the base, the iron core can be precisely positioned in the first direction, ensuring the consistency of the iron core's pole face position. This prevents insufficient tripping pressure from affecting the engagement between the iron core and the armature, thereby improving the reliability of the electromagnetic trip unit and avoiding the risk of malfunctions.

[0009] In one embodiment, the coil frame includes a frame, a first flange, and a second flange. The through hole is provided in the frame. The first flange is provided on the side of the frame away from the base. The second flange is provided on the side of the frame close to the base. The frame, the first flange, and the second flange enclose a winding space. A coil is provided in the winding space. One of the insertion protrusion and the insertion slot is provided in the second flange.

[0010] In one embodiment, the coil frame further includes a mounting portion, which is disposed on the side of the second flange opposite to the first flange and offset from the through hole; the insertion groove is disposed on the mounting portion, and the insertion protrusion is disposed on the base.

[0011] In one embodiment, the electromagnetic trip unit further includes two coil leads, both of which are located on the mounting portion. One coil lead is electrically connected to one end of the coil, and the other coil lead is electrically connected to the other end of the coil. The insertion slot is located between the two coil leads.

[0012] In one embodiment, the two coil leads are symmetrically arranged in a second direction of the base body with the insertion slot as the center, and the first direction intersects the second direction.

[0013] In one embodiment, the iron core includes a first iron core portion and a second iron core portion connected to the first iron core portion. The first iron core portion extends along a first direction, and one end of the first iron core portion away from the second iron core portion is disposed in the through hole. The second iron core portion is disposed on the base and extends along a second direction of the base. The second iron core portion is limited and engaged with the limiting portion.

[0014] In one embodiment, the first core portion includes a first segment and a second segment. The first segment is disposed inside the through hole, and the second segment is disposed outside the through hole. The second segment is connected to the first segment and the second core portion. The width of the first segment is smaller than the width of the second segment to form a shoulder on the side of the second segment close to the first segment. The shoulder abuts against the side of the second flange opposite to the first flange.

[0015] In one embodiment, the base body is further provided with a mounting groove, and the second iron core portion is disposed in the mounting groove.

[0016] In one embodiment, the mounting groove has a first groove sidewall and a groove bottom wall, the limiting part is disposed on the first groove sidewall, the limiting part, the first groove sidewall and the groove bottom wall surround to form a slot, the slot is connected to the mounting groove, and the end of the second iron core part away from the first iron core part is disposed in the slot.

[0017] In one embodiment, the first groove sidewall is provided with a rib, and the end face of the second iron core portion opposite to the first iron core portion abuts against the rib.

[0018] In one embodiment, the mounting groove further includes a second groove sidewall, a third groove sidewall, and a fourth groove sidewall. The first groove sidewall and the second groove sidewall are disposed opposite each other in the second direction, and the third groove sidewall and the fourth groove sidewall are disposed opposite each other in the third direction of the base. The insertion protrusion is provided on one of the second groove sidewall, the third groove sidewall, and the fourth groove sidewall. At least one of the second groove sidewall, the third groove sidewall, and the fourth groove sidewall is provided with a chamfered surface, which is inclined outward from the mounting groove in the direction from the bottom wall of the groove to the groove opening.

[0019] In one embodiment, at least one of the second groove sidewall, the third groove sidewall, and the fourth groove sidewall is further provided with a flat portion, the flat portion being disposed between the inclined surface and the bottom wall of the groove.

[0020] In one embodiment, the mounting groove further has a second groove sidewall opposite to the first groove sidewall, and the second groove sidewall has a protrusion on the side away from the groove bottom wall, and the insertion protrusion is provided on the protrusion.

[0021] In one embodiment, the mounting groove further has a third groove wall and a fourth groove wall, which are arranged opposite each other in the third direction of the base. The protrusion, the third groove side wall, and the fourth groove side wall are all provided with chamfered surfaces. In the direction from the bottom wall of the groove to the groove opening, the chamfered surface of the protrusion is inclined in a direction away from the first groove side wall, the chamfered surface of the third groove side wall is inclined in a direction away from the fourth groove side wall, and the chamfered surface of the fourth groove side wall is inclined in a direction away from the third groove side wall. The cross-sectional area of ​​the protrusion is larger than the cross-sectional area of ​​the insertion protrusion.

[0022] In one embodiment, the electromagnetic trip device further includes a yoke, one end of which is disposed within the space formed by the coil frame and the iron core, and abuts against the side of the second flange opposite to the first flange.

[0023] In one embodiment, the yoke includes a first yoke portion and a second yoke portion. The first yoke portion is disposed within the space formed by the coil and the iron core. The first yoke portion extends along the first direction and is fixedly connected to the iron core. At least a portion of the second yoke portion is disposed within the space formed by the coil frame and the iron core. The second yoke portion extends from the first yoke portion along the second direction of the base in a direction away from the first yoke portion. The second yoke portion abuts against the side of the second flange away from the first flange.

[0024] In one embodiment, the electromagnetic trip device further includes a magnet disposed within the space formed by the iron core and the yoke.

[0025] In one embodiment, the magnet is fixedly connected to the yoke, and the magnet and the yoke are spaced apart in the first direction.

[0026] In one embodiment, the insertion end of the plug protrusion is provided with a first chamfer, the first chamfer transitioning to the outer peripheral arc of the plug protrusion; and / or, the slot sidewall of the plug groove is provided with a second chamfer at the slot opening, the second chamfer transitioning to the slot sidewall of the plug groove.

[0027] In one embodiment, the electromagnetic trip unit further includes a housing, a yoke, a magnet, an armature, an elastic element, and a top member. The housing has a receiving cavity and an opening communicating with the receiving cavity. The base is disposed at the opening and connected to the housing. The coil frame, the iron core, the yoke, the magnet, the armature, and the elastic element are all disposed within the receiving cavity. The armature is disposed on the side of the coil frame away from the base and is used to mate with the pole face of the iron core. One end of the yoke is disposed within the space formed by the coil frame and the iron core, and the other end of the yoke is disposed on the outer periphery of the coil frame and is movably connected to the armature. The magnet is disposed within the space formed by the iron core and the yoke. One end of the elastic element is connected to the armature, and the other end of the elastic element is connected to the base. The side of the housing away from the base has a guide hole communicating with the receiving cavity. The top member is movably disposed in the guide hole and mates with the armature.

[0028] Secondly, this application also provides a circuit breaker, including a tripping mechanism and an electromagnetic trip unit as described in any of the above claims, wherein the tripping mechanism cooperates with the electromagnetic trip unit.

[0029] In the aforementioned circuit breaker, when leakage occurs and the leakage current exceeds a specified value, the electromagnetic trip unit activates, causing the tripping mechanism to operate and thus tripping the circuit breaker to disconnect the circuit. After the fault is cleared, the circuit breaker push rod closes, and the tripping mechanism pushes the electromagnetic trip unit, causing the armature of the electromagnetic trip unit to close with the iron core, and the electromagnetic trip unit then resets. During the assembly of the electromagnetic trip unit, the coil frame and the base are connected by an interference fit between the insertion protrusion and the insertion slot. The insertion protrusion and the slot wall fit tightly together, forming a relatively closed space. This confines the plastic debris generated by the friction between the insertion protrusion and the slot wall within this sealed space, preventing the plastic debris from transferring to the pole face of the iron core or the knife edge face of the yoke, thereby ensuring the stability of the magnetic circuit reluctance. This not only ensures the stability of the electromagnetic trip unit's operating current and prevents the circuit breaker from tripping erroneously under small leakage current conditions, but also prevents the armature from failing to remain closed due to insufficient magnetic force, thus preventing the circuit breaker from failing to close. In addition, by setting a limiting part in the base, the limiting part can accurately position the iron core in the first direction, ensuring the consistency of the pole face position of the iron core and preventing the circuit breaker from failing to close due to insufficient tripping pressure. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of an electromagnetic trip device according to an embodiment of this application.

[0031] Figure 2 for Figure 1 The diagram shown is an exploded view of the electromagnetic trip unit.

[0032] Figure 3 for Figure 2 The diagram shows an exploded view of the housing and base of the electromagnetic trip unit.

[0033] Figure 4 for Figure 2 The diagram shows a cross-sectional view of the electromagnetic trip unit after its housing and base are assembled.

[0034] Figure 5 This is a schematic diagram of the structure of the electromagnetic trip unit after assembly, including the base, magnetic circuit, elastic element, and pusher element, according to an embodiment of this application.

[0035] Figure 6 This is a schematic diagram of the structure of the magnetic circuit portion of the electromagnetic trip device according to an embodiment of this application, fixed to the base.

[0036] Figure 7 for Figure 6 A magnified view of a portion of point A in the middle.

[0037] Figure 8 for Figure 6 A magnified view of a portion of point B in the middle.

[0038] Figure 9 This is a schematic diagram of the structure of the base of an electromagnetic trip device according to an embodiment of this application.

[0039] Figure 10 This is a schematic diagram of the coil frame of an electromagnetic trip device according to an embodiment of this application.

[0040] Figure 11 This is a schematic diagram of the structure of the electromagnetic trip unit after the iron core, yoke and magnet are assembled according to an embodiment of this application.

[0041] Explanation of icon numbers:

[0042] 10. Housing; 11. Receiving cavity; 12. Opening; 13. Guide insertion hole; 20. Base; 21. Protrusion; 211. Insertion protrusion; 2111. First chamfer; 22. Through hole; 23. Mounting groove; 231. First groove sidewall; 2311. Limiting part; 2312. Rib; 232. Second groove sidewall; 233. Third groove sidewall; 2331. Beveled surface; 2332. Flat part; 234. Fourth groove sidewall; 235. Groove bottom wall; 236. Groove opening; 24. Slot; 30. Magnetic circuit part; 31. Coil frame; 311. Frame; 3111. Through hole; 31 2. First flange; 313. Second flange; 314. Mounting part; 3141. Insertion slot; 3142. Second chamfer; 32. Coil; 33. Iron core; 331. First iron core part; 3311. First section; 3312. Second section; 33121. Shoulder; 332. Second iron core part; 34. Yoke; 341. First yoke part; 342. Second yoke part; 343. Third yoke part; 3431. Bracket; 35. Armature; 36. Magnet; 40. Top piece; 50. Coil lead-out piece; 60. Elastic piece; Z, First direction; X, Second direction; Y, Third direction. Detailed Implementation

[0043] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0044] This application provides a circuit breaker, including a tripping mechanism and an electromagnetic trip unit, wherein the tripping mechanism cooperates with the electromagnetic trip unit.

[0045] See Figure 1 and Figure 2 An embodiment of this application provides an electromagnetic trip device, which includes a housing 10, a base 20, and a magnetic circuit portion 30.

[0046] See Figure 3 , Figure 4 and Figure 5 The housing 10 has a receiving cavity 11 and an opening 12, and the receiving cavity 11 communicates with the opening 12. The seat 20 is located in the opening 12 and is fixedly connected to the housing 10, and the magnetic circuit part 30 is located in the receiving cavity 11 and is fixedly connected to the seat 20.

[0047] See Figure 2 , Figure 5 and Figure 6The magnetic circuit section 30 includes a coil frame 31, an iron core 33, a yoke 34, an armature 35, and a magnet 36. The coil frame 31 is mounted on the base 20, and a coil 32 is wound around the outside of the coil frame 31. The coil frame 31 has a through hole 3111, which penetrates the coil frame 31 along a first direction (Z represents the first direction). One end of the iron core 33 passes through the through hole 3111, and the other end is mounted on the base 20. One end of the yoke 34 is located within the space formed by the coil frame 31 and the iron core 33, and the other end is located on the outer periphery of the coil frame 31. The armature 35 is located on the side of the magnetic circuit section 30 away from the base 20 and is movably connected to the yoke 34 via a bracket 3431. The armature 35 is used to mate with the pole face of the iron core 33. The magnet 36 is located within the space formed by the iron core 33 and the yoke 34.

[0048] See Figure 5 The electromagnetic trip unit also includes an elastic element 60 and a top element 40. One end of the elastic element 60 is connected to the armature 35, and the other end of the elastic element 60 is connected to the base 20. The housing 10 has a guide hole 13 communicating with the receiving cavity 11 on the side opposite to the base 20. The top element 40 is movably disposed in the guide hole 13. One end of the top element 40 cooperates with the armature 35, and the other end of the top element 40 cooperates with the tripping mechanism of the circuit breaker. The top element 40 is used to drive the tripping mechanism of the circuit breaker to operate, or the tripping mechanism of the circuit breaker pushes the top element 40 to reset the electromagnetic trip unit.

[0049] The electromagnetic trip unit in this embodiment can utilize the "magnetic flux differential" function to enable the armature 35 to operate under ultra-low power. The principle of "magnetic flux differential" is as follows:

[0050] When armature 35 is closed and coil 32 is not energized, the magnetic flux of magnet 36 flows through magnetic circuits φ0 and φ2.

[0051] When the armature 35 is closed and the coil 32 is energized, the magnetic flux generated by the coil 32 forms a magnetic circuit φ1. The magnetic flux φ1 of the magnetic circuit of the coil 32 is opposite in direction to the magnetic flux of the magnetic circuit φ0. The magnetic resistance of the magnet 36 in the magnetic circuit φ0 of the magnet increases, and the magnetic circuit φ2 of the magnet becomes a short circuit of the magnetic flux of the magnet 36. As a result, the magnetic flux of the magnet 36 decreases at the pole face of the armature 35, and the armature 35 moves under the action of the elastic element 60.

[0052] In one embodiment, see Figure 6The iron core 33 includes a first iron core portion 331 and a second iron core portion 332 connected to the first iron core portion 331. The first iron core portion 331 extends along a first direction Z, and one end of the first iron core portion 331 opposite to the second iron core portion 332 passes through a through hole 3111. The second iron core portion 332 extends along a second direction X and is disposed on the base 20. The first direction and the second direction intersect. Optionally, the first direction and the second direction are perpendicular, and X represents the second direction.

[0053] See Figure 6 and Figure 8 The base 20 is provided with a limiting part 2311, which is used to restrict the movement of the iron core 33 in the first direction. Specifically, the limiting part 2311 is engaged with the end of the second iron core 332 that is away from the first iron core 331. By providing the limiting part 2311 in the base 20, the limiting part 2311 can accurately position the iron core 33 in the first direction, ensuring the consistency of the pole face position of the iron core 33. When the armature 35 is attracted to the iron core 33, the length of the top member 40 extending out of the housing 10 is constant. This can avoid the iron core 33 and the armature 35 being affected by insufficient tripping pressure, ensuring the stability of the tripping current of the electromagnetic trip device, thereby preventing the electromagnetic trip device from malfunctioning.

[0054] One of the base 20 and the coil frame 31 is provided with a plug-in protrusion 211, and the other of the base 20 and the coil frame 31 is provided with a plug-in groove 3141. The plug-in protrusion 211 is located in the plug-in groove 3141 and is interference-fitted with the plug-in groove 3141.

[0055] Specifically, in this embodiment, see [reference] Figure 6 The insertion protrusion 211 is provided on the base 20, and the insertion slot 3141 is provided on the coil frame 31.

[0056] During assembly, the insertion protrusion 211 is positioned opposite the opening of the insertion groove 3141. External force is applied to the base 20 and / or the coil frame 31, causing them to approach each other. The insertion protrusion 211 enters the insertion groove 3141. Due to the interference fit between the insertion protrusion 211 and the insertion groove 3141, the protrusion 211 and the groove wall of the insertion groove 3141 are tightly fitted, forming a relatively enclosed space. This allows the plastic debris generated by the friction between the insertion protrusion 211 and the groove wall of the insertion groove 3141 to be effectively contained. Confined within this sealed space, plastic debris is prevented from transferring to the pole face of the iron core 33 or the knife edge face of the yoke 34. Thus, when the armature 35 contacts the pole face of the iron core 33, there will be no plastic debris between the armature 35 and the iron core 33. This prevents the magnetic resistance of the magnetic circuit φ0 of the magnet 36 from increasing, which would cause the attraction force of the magnetic circuit φ0 of the magnet 36 to be less than the reaction force of the elastic element 60. This ensures that the armature 35 and the iron core 33 are reliably attracted, keeps the tripping current of the electromagnetic trip device stable, and prevents the electromagnetic trip device from malfunctioning.

[0057] In one embodiment, see Figure 7 The insertion end of the insertion protrusion 211 is provided with a first chamfer 2111, and the groove sidewall of the insertion groove 3141 is provided with a second chamfer 3142 corresponding to the groove opening.

[0058] It should be noted that if the insertion protrusion 211 is located on the base 20, the insertion end of the insertion protrusion 211 refers to the end of the insertion protrusion 211 that is away from the base 20. If the insertion protrusion 211 is located on the coil frame 31, the insertion end of the insertion protrusion 211 refers to the end of the insertion protrusion 211 that is away from the coil frame 31.

[0059] It should be noted that the end of the plug slot 3141 with the slot opening is a horn structure, and the large end face of the horn structure is set close to the slot opening of the plug slot 3141.

[0060] During assembly, the insertion end of the plug protrusion 211 is aligned with the opening of the plug groove 3141. Then, external force is applied to the base 20 and / or the coil frame 31. Under the guiding cooperation of the first chamfer 2111 and the second chamfer 3142, the plug protrusion 211 can automatically center and slide into the plug groove 3141, which helps to improve assembly efficiency.

[0061] Of course, in other embodiments, the first chamfer 2111 may be provided only at the insertion end of the insertion protrusion 211. Alternatively, the second chamfer 3142 may be provided only at the portion of the groove sidewall of the insertion groove 3141 corresponding to the groove opening.

[0062] Further, see Figure 7 The first chamfer 2111 transitions to the outer periphery of the insertion protrusion 211 with a rounded arc, and the second chamfer 3142 transitions to the side wall of the insertion groove 3141 with a rounded arc. This rounded transition transforms sharp corners into smooth curved surfaces, reducing plastic debris generated during the insertion of the protrusion 211 and the insertion groove 3141. Simultaneously, the rounded surface disperses stress, preventing cracks or burrs from forming at the openings of the protrusion 211 and the insertion groove 3141, thus ensuring the fitting accuracy between the protrusion 211 and the insertion groove 3141.

[0063] In one embodiment, see Figure 6 and Figure 10The coil holder 31 includes a frame 311, a first flange 312, and a second flange 313. A through hole 3111 is provided in the frame 311. The first flange 312 is provided at one end of the frame 311 in a first direction, and the second flange 313 is provided at the other end of the frame 311 in the first direction. The second flange 313 is positioned relative to the first flange 312 and close to the base 20. The coil 32 is disposed within the winding space formed by the frame 311, the first flange 312, and the second flange 313. In this way, the first flange 312 and the second flange 313 can limit the coil 32, preventing the coil 32 from moving in the first direction and ensuring the stability of the tripping current of the electromagnetic trip device.

[0064] In one embodiment, see Figure 6 and Figure 10 The coil frame 31 also includes a mounting portion 314. The mounting portion 314 is located on the side of the second flange 313 opposite to the first flange 312 and is offset from the through hole 3111. Specifically, in this embodiment, the mounting portion 314 is located on the side of the first core portion 331 opposite to the yoke 34. A insertion slot 3141 is provided on the mounting portion 314. By offsetting the mounting portion 314 from the through hole 3111, interference between the core 33 and the mounting portion 314 can be avoided. By placing the mounting portion 314 between the second flange 313 and the base 20, the overall structure is compact, facilitating miniaturization. Simultaneously, the mounting portion 314 provides a location for the insertion slot 3141, eliminating the need to provide insertion slots 3141 in other parts of the coil frame 31 and preventing interference between the insertion protrusion 211 and the coil 32.

[0065] In one embodiment, see Figure 1 and Figure 6 The electromagnetic trip unit also includes a coil lead 50. There are two coil leads 50, both of which are located in the mounting part 314. One coil lead 50 is electrically connected to one end of the coil 32, and the other coil lead 50 is electrically connected to the other end of the coil 32.

[0066] See Figure 1 and Figure 9 The base 20 is also provided with two through holes 22, and two coil leads 50 pass through the two through holes 22 one by one. The ends of the two coil leads 50 facing away from the coil 32 are both located outside the receiving cavity 11. By providing two coil leads 50, the coil 32 can be connected to an external circuit.

[0067] In one embodiment, see Figure 10 The insertion slot 3141 is located between the two coil leads 50. In this way, the volume of the coil frame 31 is avoided due to the insertion slot 3141, making the overall structure compact and facilitating miniaturization.

[0068] Further, see Figure 10 Two coil leads 50 are spaced apart along a third direction, and a insertion slot 3141 is located between the two coil leads 50. The second direction intersects the third direction. Optionally, the second direction is perpendicular to the third direction, and the third direction is represented by Y. By using the base 20 to position the two coil leads 50 in the third direction, the overall structure becomes compact.

[0069] Specifically, in this embodiment, see [reference] Figure 6 Both coil leads 50 are located on the side of the iron core 33 away from the yoke 34 to avoid interference between the coil leads 50 and the yoke 34. (See reference...) Figure 10 Two coil leads 50 are spaced apart along a third direction. The two coil leads 50 are symmetrically arranged on both sides of the insertion slot 3141, so that the force acting on the coil frame 31 is symmetrical, reducing the deformation or damage of the coil frame 31 due to uneven force.

[0070] In one embodiment, see Figure 6 and Figure 11 The first core portion 331 includes a first segment 3311 and a second segment 3312. The first segment 3311 passes through the through hole 3111, and the second segment 3312 is disposed outside the through hole 3111. The second segment 3312 is connected to the first segment 3311 and the second core portion 332. The length of the first segment 3311 in a third direction is less than the length of the second segment 3312 in a third direction, so that a shoulder 33121 is formed on the side of the second segment 3312 near the first segment 3311.

[0071] Further, see Figure 6 and Figure 11 The second flange 313 abuts against the shoulder 33121. Thus, the coil frame 31 presses down on the iron core 33, effectively positioning the iron core 33 in the first direction. Simultaneously, the coil frame 31 is fixedly connected to the base 20 via the insertion protrusion 211 and the insertion slot 3141. This reliably fixes the magnetic circuit portion 30, ensuring the electromagnetic trip unit's structure is robust and preventing the magnetic circuit portion 30 from loosening during use, which could lead to unstable parameters or even failure of the electromagnetic trip unit.

[0072] Specifically, in this embodiment, the first segment 3311 is located in the middle of the second segment 3312 in a third direction, so that shoulders 33121 are formed on both sides of the first segment 3311. The second flange 313 abuts against the shoulders 33121 on both sides of the first segment 3311.

[0073] In one embodiment, see Figure 6 and Figure 9The base 20 is also provided with a mounting groove 23. The second iron core 332 is disposed in the mounting groove 23. In this way, the mounting groove 23 can accommodate the second iron core 332, reducing the height of the electromagnetic trip device. At the same time, the side wall of the mounting groove 23 can limit the iron core 33, improving the stability of the iron core 33 during installation.

[0074] In one embodiment, see Figure 8 and Figure 9 The mounting groove 23 has a first groove sidewall 231 and a groove bottom wall 235. A limiting part 2311 is provided on the first groove sidewall 231. Specifically, the limiting part 2311 is provided on the side of the first groove sidewall 231 opposite to the groove bottom wall 235. The limiting part 2311, the first groove sidewall 231, and the groove bottom wall 235 form a retaining groove 24, which communicates with the mounting groove 23. The end of the second iron core part 332 opposite to the first iron core part 331 is provided in the retaining groove 24. In this way, the limiting part 2311 and the groove bottom wall 235 cooperate to restrict the movement of the iron core 33 in the first direction, while the first groove sidewall 231 can restrict the movement of the iron core 33 in the second direction, thereby improving the reliability of the iron core 33 installation.

[0075] Further, see Figure 8 The first groove sidewall 231 is provided with a raised rib 2312, and the end face of the second iron core 332 facing away from the first iron core 331 abuts against the raised rib 2312. By setting the raised rib 2312, which serves as a positioning reference, the position of the iron core 33 in the second direction is consistent, ensuring the consistency of the electromagnetic trip device's performance. It also compensates for manufacturing tolerances, reduces machining precision, and improves assembly yield. Furthermore, it reduces the contact area, lowers frictional resistance, and avoids the generation of excessive plastic debris during the assembly of the second iron core 332 into the mounting groove 23.

[0076] In one embodiment, see Figure 9 The mounting groove 23 also has a second groove sidewall 232, a third groove sidewall 233, and a fourth groove sidewall 234. The first groove sidewall 231 and the second groove sidewall 232 are disposed opposite each other in a second direction, and the third groove sidewall 233 and the fourth groove sidewall 234 are disposed opposite each other in a third direction. A plug-in protrusion 211 is provided on the second groove sidewall 232. Thus, the second groove sidewall 232 provides a mounting position for the plug-in protrusion 211, such that the plug-in protrusion 211 is disposed opposite to the limiting portion 2311.

[0077] Further, see Figure 9At least one of the second slot sidewall 232, the third slot sidewall 233, and the fourth slot sidewall 234 is provided with a chamfered surface 2331, which slopes outward from the mounting slot 23 in the direction from the bottom wall 235 to the slot opening 236. By providing the chamfered surface 2331, it can serve as a guide, facilitating the rapid assembly of the iron core 33 into the mounting slot 23 and improving assembly efficiency.

[0078] In one embodiment, see Figure 9 The second groove sidewall 232 is provided with a protrusion 21, and the insertion protrusion 211 is provided on the protrusion 21. In this way, the height of the insertion protrusion 211 can be shortened, the insertion stroke can be shortened, and the assembly efficiency can be improved. In addition, the cross-sectional area of ​​the protrusion 21 is larger than the cross-sectional area of ​​the insertion protrusion 211, which can also reduce the risk of breakage of the insertion protrusion 211.

[0079] Further, see Figure 9 The protrusion 21, the third groove sidewall 233, and the fourth groove sidewall 234 are all provided with inclined surfaces 2331. Specifically, in the direction from the groove bottom wall 235 to the groove opening 236, the inclined surface 2331 of the protrusion 21 is inclined away from the first groove sidewall 231, the inclined surface 2331 of the third groove sidewall 233 is inclined away from the fourth groove sidewall 234, and the inclined surface 2331 of the fourth groove sidewall 234 is inclined away from the third groove sidewall 233. Thus, the inclined surfaces 2331 of the protrusion 21, the third groove sidewall 233, and the fourth groove sidewall 234 can all guide the iron core 33 to be quickly assembled into the mounting groove 23, improving the assembly efficiency of the iron core 33.

[0080] Specifically, in this embodiment, the protrusion 21 is located at the middle of the second groove sidewall 232 along the third direction, and the protrusion 21 has a sloping surface 2331 that is inclined away from the first groove sidewall 231. The third groove sidewall 233 has a sloping surface 2331 that is inclined away from the fourth groove sidewall 234 at the part near the first groove sidewall 231, and the fourth groove sidewall 234 has a sloping surface 2331 that is inclined away from the third groove sidewall 233 at the part near the first groove sidewall 231.

[0081] In one embodiment, see Figure 6 and Figure 9At least one of the second groove sidewall 232, the third groove sidewall 233, and the fourth groove sidewall 234 is further provided with a flat portion 2332, which is located between the inclined surface 2331 and the groove bottom wall 235. When the second iron core portion 332 is assembled into the mounting groove 23, the side of the second iron core portion 332 makes surface contact with the flat portion 2332, avoiding the slight positional deviation that may occur due to only the inclined surface 2331, so that the iron core 33 is accurately positioned. At the same time, it can also improve the reliability of the assembly of the iron core 33 and prevent the iron core 33 from shaking in the mounting groove 23.

[0082] In one embodiment, see Figure 6 One end of the yoke 34 is located within the space formed by the coil frame 31 and the iron core 33, and the side of the second flange 313 facing away from the first flange 312 is in clearance fit with the yoke 34. (See reference...) Figure 6 The first yoke 34 includes a first yoke portion 341 and a second yoke portion 342. The first yoke portion 341 is disposed within the space formed by the coil 32 and the iron core 33, extends along a first direction, and is fixedly connected to the first iron core portion 331. The end of the second yoke portion 342 near the first yoke portion 341 is disposed within the space formed by the coil frame 31 and the iron core 33, and extends from the first yoke portion 341 along a second direction in a direction away from the first yoke portion 341. The second yoke portion 342 is clearance-fitted with the second flange 313. This provides a shorter and more efficient path for the magnetic field lines.

[0083] Further, see Figure 5 and Figure 6 The yoke 34 also includes a third yoke portion 343. The third yoke portion 343 is located on the outer periphery of the coil frame 31 and extends from the second yoke portion 342 in a first direction away from the second yoke portion 342. The third yoke portion 343 is provided with a bracket 3431, and the armature 35 is movably connected to the bracket 3431.

[0084] In one embodiment, see Figure 6 A magnet 36 is disposed between the second iron core 332 and the second yoke 342, and is fixedly connected to the second iron core 332, with a gap between them. Because of this gap, the magnetic flux generated by the magnet 36 can be precisely controlled and distributed, ensuring that a sufficient proportion of the magnetic flux is guided to the correct working path to complete the effective attraction work. When the circuit breaker's tripping mechanism pushes the top member 40 to attract the armature 35, closing the entire magnetic circuit, a magnetic loop φ0 is formed. At this point, the magnetic force of the magnet 36 itself is sufficient to maintain the closed state of the magnetic circuit 30, without the need for an external coil 32 to continue providing energy.

[0085] In this embodiment, during assembly, the electromagnetic trip unit is positioned so that the insertion protrusion 211 is opposite to the slot 236 of the insertion groove 3141. An external force is applied to the base 20 and / or the coil frame 31, causing the base 20 and the coil frame 31 to approach each other. The insertion protrusion 211 enters the insertion groove 3141. Due to the interference fit between the insertion protrusion 211 and the insertion groove 3141, the insertion protrusion 211 and the groove wall of the insertion groove 3141 are tightly fitted, forming a relatively closed space. In this way, the plastic debris formed by the scraping between the insertion protrusion 211 and the groove wall of the insertion groove 3141 can be confined within this sealed space, preventing the plastic debris from transferring to the pole face of the iron core 33 or the knife edge face of the yoke 34. This ensures that the armature 35 and the iron core 33 are reliably attracted, keeps the tripping current of the electromagnetic trip unit stable, and prevents the electromagnetic trip unit from malfunctioning. Furthermore, by setting a limiting part 2311 in the base 20, the limiting part 2311 can accurately position the iron core 33 in the first direction Z, ensuring the consistency of the pole face position of the iron core 33. When the armature 35 is attracted to the iron core 33, the length of the top member 40 extending out of the housing 10 is constant. This can avoid the iron core 33 and the armature 35 being affected by the tripping pressure not being in place, thereby improving the reliability of the electromagnetic trip device and avoiding the risk of malfunction.

[0086] In this embodiment, when a leakage current occurs and exceeds a specified value, the electromagnetic trip unit activates. The top piece 40 of the electromagnetic trip unit extends, causing the tripping mechanism to operate and thus opening the circuit breaker to disconnect the circuit. After the fault is cleared, the circuit breaker push rod closes, and the tripping mechanism pushes the top piece 40 of the electromagnetic trip unit, causing the armature 35 of the push unit to close with the iron core 33, and the trip unit resets.

[0087] During the assembly of the electromagnetic trip unit, the coil frame 31 and the base 20 are connected by an interference fit between the insertion protrusion 211 and the insertion slot 3141. The insertion protrusion 211 and the slot wall of the insertion slot 3141 fit tightly together to form a relatively closed space. In this way, the plastic debris formed by the scraping between the insertion protrusion 211 and the slot wall of the insertion slot 3141 can be confined within this sealed space, preventing the plastic debris from transferring to the pole face of the iron core 33 or the knife edge face of the yoke 34. This ensures the stability of the magnetic circuit resistance and keeps the attraction force of the magnet 36 on the armature 35 constant. This not only ensures the stability of the operating current of the electromagnetic trip unit and avoids the circuit breaker from tripping erroneously under small leakage current conditions, but also prevents the armature 35 from failing to remain closed due to insufficient magnetic force, thus preventing the circuit breaker from failing to close. In addition, by setting a limiting part 2311 in the base body 20, the limiting part 2311 can accurately position the iron core 33 in the first direction Z, ensuring the consistency of the pole face position of the iron core 33. When the armature 35 is attracted to the iron core 33, the length of the top part 40 extending out of the housing 10 is constant, which can prevent the circuit breaker from failing to close due to insufficient tripping pressure.

[0088] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms 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 application 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 a limitation of this application.

[0089] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0090] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0091] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0092] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0093] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An electromagnetic trip unit, characterized in that, include: The seat body is provided with a limiting part; A coil holder, the coil holder being mounted on the base, one of the coil holder and the base having a insertion groove, the other of the coil holder and the base having a insertion protrusion, the insertion protrusion being disposed within the insertion groove and having an interference fit with the insertion groove, the coil holder also having a through hole extending along a first direction of the base; and An iron core, one end of which passes through the through hole and is used to cooperate with the armature, and the other end of which is disposed in the base and cooperates with the limiting part to restrict the movement of the iron core along the first direction.

2. The electromagnetic trip unit according to claim 1, characterized in that, The coil frame includes a frame, a first flange, and a second flange. The through hole is provided in the frame. The first flange is provided on the side of the frame away from the base. The second flange is provided on the side of the frame close to the base. The frame, the first flange, and the second flange enclose a winding space. A coil is provided in the winding space. One of the insertion protrusion and the insertion slot is provided in the second flange.

3. The electromagnetic trip unit according to claim 2, characterized in that, The coil frame also includes a mounting part, which is located on the side of the second flange opposite to the first flange and is offset from the through hole; The insertion slot is provided on the mounting part, and the insertion protrusion is provided on the base.

4. The electromagnetic trip unit according to claim 3, characterized in that, The electromagnetic trip unit also includes two coil leads, both of which are located on the mounting portion. One coil lead is electrically connected to one end of the coil, and the other coil lead is electrically connected to the other end of the coil. The insertion slot is located between the two coil leads.

5. The electromagnetic trip unit according to claim 4, characterized in that, The two coil leads are symmetrically arranged in the second direction of the base body with the insertion slot as the center, and the first direction intersects the second direction.

6. The electromagnetic trip unit according to claim 2, characterized in that, The iron core includes a first iron core portion and a second iron core portion connected to the first iron core portion. The first iron core portion extends along the first direction. One end of the first iron core portion away from the second iron core portion is disposed in the through hole. The second iron core portion is disposed on the base and extends along the second direction of the base. The second iron core portion is limited and engaged with the limiting portion.

7. The electromagnetic trip unit according to claim 6, characterized in that, The first iron core portion includes a first segment and a second segment. The first segment is disposed inside the through hole, and the second segment is disposed outside the through hole. The second segment is connected to the first segment and the second iron core portion. The width of the first segment is smaller than the width of the second segment, so that a shoulder is formed on the side of the second segment close to the first segment. The shoulder abuts against the side of the second flange opposite to the first flange.

8. The electromagnetic trip unit according to claim 6, characterized in that, The base body is also provided with a mounting groove, and the second iron core is disposed in the mounting groove.

9. The electromagnetic trip unit according to claim 8, characterized in that, The mounting groove has a first groove sidewall and a groove bottomwall. The limiting part is provided on the first groove sidewall. The limiting part, the first groove sidewall and the groove bottomwall surround to form a slot. The slot communicates with the mounting groove. One end of the second iron core part away from the first iron core part is provided in the slot.

10. The electromagnetic trip unit according to claim 9, characterized in that, The first groove sidewall is provided with a raised rib, and the end face of the second iron core part opposite to the first iron core part abuts against the raised rib.

11. The electromagnetic trip unit according to claim 9, characterized in that, The mounting groove also has a second groove sidewall, a third groove sidewall, and a fourth groove sidewall. The first groove sidewall and the second groove sidewall are arranged opposite to each other in the second direction. The third groove sidewall and the fourth groove sidewall are arranged opposite to each other in the third direction of the base. The insertion protrusion is provided on one of the second groove sidewall, the third groove sidewall, and the fourth groove sidewall. At least one of the second, third, and fourth groove sidewalls is provided with a chamfered surface, which is inclined outward from the mounting groove in the direction from the bottom wall of the groove to the groove opening.

12. The electromagnetic trip unit according to claim 11, characterized in that, At least one of the second, third, and fourth groove sidewalls is further provided with a flat portion, which is located between the inclined surface and the bottom wall of the groove.

13. The electromagnetic trip unit according to claim 9, characterized in that, The mounting groove also has a second groove sidewall opposite to the first groove sidewall, and the second groove sidewall has a protrusion on the side away from the bottom wall of the groove, and the insertion protrusion is provided on the protrusion.

14. The electromagnetic trip unit according to claim 13, characterized in that, The mounting groove also has a third groove wall and a fourth groove wall, which are arranged opposite each other in the third direction of the base. The protrusion, the third groove side wall, and the fourth groove side wall are all provided with chamfered surfaces. In the direction from the bottom wall of the groove to the groove opening, the chamfered surface of the protrusion is inclined in the direction away from the first groove side wall, the chamfered surface of the third groove side wall is inclined in the direction away from the fourth groove side wall, and the chamfered surface of the fourth groove side wall is inclined in the direction away from the third groove side wall. The cross-sectional area of ​​the protrusion is larger than the cross-sectional area of ​​the insertion protrusion.

15. The electromagnetic trip unit according to any one of claims 2 to 14, characterized in that, The electromagnetic trip unit also includes a yoke, one end of which is located within the space formed by the coil frame and the iron core, and abuts against the side of the second flange opposite to the first flange.

16. The electromagnetic trip unit according to claim 15, characterized in that, The yoke includes a first yoke portion and a second yoke portion. The first yoke portion is disposed within the space formed by the coil and the iron core. The first yoke portion extends along the first direction and is fixedly connected to the iron core. At least a portion of the second yoke portion is disposed within the space formed by the coil frame and the iron core. The second yoke portion extends from the first yoke portion along the second direction of the base body in a direction away from the first yoke portion. The second yoke portion abuts against the side of the second flange away from the first flange.

17. The electromagnetic trip unit according to claim 15, characterized in that, The electromagnetic trip unit also includes a magnet, which is disposed within the space formed by the iron core and the yoke.

18. The electromagnetic trip unit according to claim 17, characterized in that, The magnet is fixedly connected to the yoke, and the magnet and the yoke are spaced apart in the first direction.

19. The electromagnetic trip unit according to any one of claims 1 to 14, characterized in that, The insertion end of the plug-in protrusion is provided with a first chamfer, and the first chamfer transitions with the outer peripheral arc of the plug-in protrusion; And / or, the slot sidewall of the plug groove is provided with a second chamfer at the slot opening, and the second chamfer transitions to the arc of the slot sidewall of the plug groove.

20. The electromagnetic trip unit according to any one of claims 1 to 14, characterized in that, The electromagnetic trip unit further includes a housing, a yoke, a magnet, an armature, an elastic element, and a top element. The housing has a receiving cavity and an opening communicating with the receiving cavity. The base is located at the opening and connected to the housing. The coil frame, the iron core, the yoke, the magnet, the armature, and the elastic element are all located within the receiving cavity. The armature is located on the side of the coil frame away from the base and is used to mate with the pole face of the iron core. One end of the yoke is located within the space formed by the coil frame and the iron core, and the other end of the yoke is located on the outer periphery of the coil frame and is movably connected to the armature. The magnet is located within the space formed by the iron core and the yoke. One end of the elastic element is connected to the armature, and the other end of the elastic element is connected to the base. The side of the housing away from the base has a guide hole communicating with the receiving cavity. The top element is movably located in the guide hole and mates with the armature.

21. A circuit breaker comprising a tripping mechanism and an electromagnetic trip unit as described in any one of claims 1-20, wherein the tripping mechanism cooperates with the electromagnetic trip unit.

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