Miniature circuit breaker

Abstract

A miniature circuit breaker comprises a base, two sides of the base are detachably connected with an upper cover and a lower cover respectively, an operating mechanism mounting groove is formed between the base and the upper cover, a button mounting groove is formed between the base and the lower cover, and the miniature circuit breaker further comprises a mounting seat integrally formed on the base. The mounting seat comprises a reset groove used for mounting a reset assembly and a test groove used for mounting a test assembly, the base comprises an operation plate, limiting walls located on one side of the reset groove and one side of the test groove are arranged on the two sides of the base, and the limiting walls comprise an anti-falling wall close to one side of the operation plate and a mounting wall away from one side of the operation plate; the heights of the anti-falling wall and the mounting wall are greater than the depths of the reset groove and the test groove, and the height of the anti-falling wall is greater than the height of the mounting wall. The utility model has the beneficial effects that through the integrally formed mounting seat structure, the development complexity of a mold is effectively reduced, and the production cost is reduced. And the height difference design of the anti-falling wall and the mounting wall forms a stepped limiting structure, so that the reset assembly and the test assembly are allowed to be quickly mounted.

Description

TECHNICAL FIELD

[0001] The utility model relates to an electrical equipment especially a small circuit breaker. BACKGROUND

[0002] As a core protection device in low-voltage distribution system, small circuit breaker is widely used in terminal power distribution field of residential buildings, commercial places and industrial equipment. It mainly realizes overload and short-circuit protection through thermal magnetic tripping principle. When the line current exceeds the set threshold, the bimetallic strip is heated and bent to trigger the mechanical linkage mechanism to perform the breaking operation. In actual use, the user restores the circuit conduction state by operating the reset button on the panel, and verifies the reliability of the tripping mechanism regularly with the help of the test button. With the development of intelligence, modern small circuit breakers generally integrate electronic tripping units and status indication modules, which not only guarantee the rated breaking capacity, but also meet the strict requirements for electrical clearance and creepage distance.

[0003] In the existing manufacturing process, there is a significant contradiction in the installation structure design of the reset button and the test button. The traditional scheme directly forms the button mounting rack during the injection molding of the base body, which can reduce the mold development cost, but due to the limitation of the demolding angle, the elastic components need to be forcibly pressed during assembly, which may cause button jamming or reset spring deformation. The alternative scheme uses an independent injection molded mounting rack assembly, which improves assembly convenience, but increases the number of molds, significantly increasing production costs. Both methods are difficult to balance economy and reliability, especially under the trend of miniaturization, the space compression of the installation cavity exacerbates the deviation problem of the guide column, affecting the button stroke accuracy and contact pressure stability, restricting the product yield improvement and function expansion. SUMMARY

[0004] In view of the deficiencies of the prior art, the utility model provides a small circuit breaker which is convenient for test and reset button assembly and also considers the manufacturing cost.

[0005] To achieve the above purpose, the technical scheme of the utility model is as follows: a small circuit breaker, comprising a base, the two sides of the base are detachably connected with an upper cover and a lower cover, an operating mechanism installation slot is formed between the base and the upper cover, a button installation slot is formed between the base and the lower cover, further comprising a mounting seat integrally formed on the base, the mounting seat comprises a reset slot for mounting a reset component and a test slot for mounting a test component, the base comprises an operating plate, the two sides of the base are provided with a limiting wall on one side of the reset slot and the test slot, the limiting wall comprises an anti-drop wall close to the operating plate and a mounting wall away from the operating plate, the height of the anti-drop wall and the mounting wall is greater than the slot depth of the reset slot and the test slot, and the height of the anti-drop wall is greater than the height of the mounting wall.

[0006] The utility model discloses beneficial effect is: through the integrated mounting seat structure, effectively reduce the mould development complexity and assembly process, reduce production cost. The height difference design of anti -drop wall and installation wall forms the ladder type spacing structure, both allow reset component and test component to be loaded from the non -operating board side fast, and can prevent the component reverse drop in the installation process through the blocking effect of anti -drop wall. As a preferred mode, the top of installation wall can set up the inclined plane of direction, and the vertical surface of anti -drop wall forms the gradual spacing channel, both guarantee the smooth advance when the component installation, and realize final spacing locking through the vertical surface of anti -drop wall. In addition, the structure that anti -drop wall height is greater than installation wall forms double blocking after the component loading, even if the vibration impact can avoid the axial displacement of component.

[0007] Further, the reset component includes a reset button and a reset spring sleeved on the reset button and used for ejecting the reset button, the reset slot includes a spring mounting wall on which the reset spring is abutted away from the operating plate side, a limiting slot for inserting the reset button is arranged at the center of the spring mounting wall, the limiting slot allows the reset button to move only up and down, and a guide wall is arranged on the side of the spring mounting wall close to the lower cover and inclined to the direction away from the operating plate so as to facilitate the reset button with the reset spring to be loaded.

[0008] The technical scheme realizes accurate positioning and installation of the reset component through cooperation of the guide wall and the limiting slot. The inclined guide wall can guide the reset spring to slide into the reset slot along a predetermined path in a compressed state, avoiding the jamming problem caused by lateral deviation of the spring. The linear guide structure of the limiting slot ensures that the reset button only has axial movement freedom, improving operation stability. As a preferred mode, anti-rotation ribs can be arranged on the inner wall of the limiting slot and cooperate with corresponding grooves on the side of the reset button, further limiting the rotation freedom. The inclination angle of the guide wall can be designed to form a certain angle with the compression direction of the reset spring, which provides sufficient guide effect and does not affect the axial compression stroke of the spring.

[0009] Further, the reset component further includes a lock plate for unlocking the reset button when tripping, the reset slot includes a rotating hole for inserting the lock plate therein so that the lock plate rotates therearound and a lock plate mounting wall for facilitating the lock plate to be loaded away from the operating plate side, and the lock plate mounting wall is inclined to the direction away from the operating plate on the side close to the lower cover.

[0010] The inclined design of the lock plate mounting wall significantly simplifies the assembly process of the lock plate. During installation, the lock plate can naturally slide along the inclined surface into the rotating hole for positioning, avoiding the need for precise alignment of traditional vertical mounting walls. The gap between the rotating hole and the lock plate shaft allows smooth rotation of the lock plate when triggered. As a preferred method, the end of the lock plate mounting wall can be provided with an arc-shaped transition section that matches the edge profile of the lock plate, forming a self-locking structure after installation. The inner wall of the rotating hole can be provided with a wear-resistant coating to reduce frictional wear caused by long-term operation of the lock plate, extending its service life.

[0011] Further, the test assembly includes a static contact, a dynamic contact, a test button for driving the static and dynamic contacts into contact, and a test spring for driving the test button to reset, the test slot includes a static contact placement slot and a dynamic contact placement slot for placing the static and dynamic contacts respectively, and an insulating wall is arranged between the static contact placement slot and the dynamic contact placement slot to prevent creepage between the static and dynamic contacts.

[0012] The introduction of the insulating wall effectively solves the risk of arc creep caused by insufficient contact spacing in traditional circuit breaker test assemblies. The independent placement slot structure of the static and dynamic contacts not only achieves physical isolation, but also forms double protection through the insulating wall. As a preferred method, the top of the insulating wall can extend out an isolation eave structure, covering the area above the contact area and blocking the three-dimensional path that the arc may take. The bottom of the static contact placement slot can be provided with concave-convex positioning lines to increase the contact area between the contact and the base, improving heat dissipation performance while preventing contact displacement.

[0013] Further, one end of the dynamic contact near the test button is inclined, and a bent wall with an inclination angle matching that of the inclined part of the dynamic contact is arranged in the test slot. The bent wall cooperates with the inclined part of the dynamic contact to ensure that the inclined part of the dynamic contact always abuts against the test button.

[0014] The inclined surface of the bent wall and the dynamic contact achieves a stable force transmission relationship, ensuring the synchronous and accurate response of the dynamic contact when the test button is actuated. This structure automatically compensates for the elastic deformation of the contact, preventing contact pressure decay caused by long-term use. As a preferred method, the surface of the bent wall can be processed with a wave-shaped friction pattern, forming multiple-point contact with the inclined surface of the dynamic contact, ensuring contact stability while allowing for slight displacement adjustment of the contact. The inclined end of the dynamic contact can be provided with a spherical protrusion, forming point-surface contact with the groove of the test button to reduce frictional resistance.

[0015] Further, the static contact placement slot and the dynamic contact placement slot are provided with welding grooves on the side away from the operation plate for welding wires.

[0016] The structural design of the welding groove realizes accurate positioning of the wire connection, avoids the risk of short circuit caused by solder overflow during welding. The groove depth control can ensure consistent wire insertion depth and improve the stability of welding quality. As a preferred mode, the side wall of the welding groove can be provided with a semi-closed baffle to form a solder containing cavity, which facilitates soldering operation and controls the solder flow range. The groove bottom can be additionally provided with a heat dissipation fin structure to accelerate heat dissipation during welding and prevent the plastic base from deforming due to high temperature.

[0017] Further, the lower cover is provided with a clamping wall corresponding to the limiting groove, the clamping wall comprises a positioning wall embedded in the inner side of the anti-falling wall and an encapsulation wall in the same horizontal plane as the mounting wall, and the distance difference between the positioning wall and the encapsulation wall is equivalent to the thickness of the limiting wall.

[0018] The double-layer structure design of the clamping wall realizes multiple positioning of the lower cover and the base, the embedding of the positioning wall and the anti-falling wall ensures assembly accuracy, and the flush of the encapsulation wall and the mounting wall ensures the integrity of the appearance. As a preferred mode, the inner side of the positioning wall can be provided with an elastic buckle structure, which forms an interference fit with the groove on the outer side of the anti-falling wall, which facilitates assembly and effectively absorbs vibration impact. The edge of the encapsulation wall can be designed as a stepped sealing surface to form a labyrinth sealing structure with the mounting wall, improving dust and water resistance. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a disassembled view of the embodiment of the utility model;

[0020] Figure 2 It is an internal view of the button mounting groove of the embodiment of the utility model

[0021] Figure 3 It is a partial enlarged view of the reset groove of the mounting seat of the embodiment of the utility model;

[0022] Figure 4 It is a partial enlarged view of the test groove of the mounting seat of the embodiment of the utility model;

[0023] Figure 5 It is a partial enlarged view of the limiting wall and the clamping wall of the embodiment of the utility model. DETAILED DESCRIPTION

[0024] The embodiment of the utility model is a small circuit breaker such as Figures 1-5As shown: including the base 1, the two sides of the base 1 are respectively detachably connected with the upper cover 2 and the lower cover 3. The base 1 and the upper cover 2 form the operation mechanism mounting groove 4, and the base 1 and the lower cover 3 form the button mounting groove 5. The base 1 is integrally formed with a mounting seat 11, and the mounting seat 11 has a reset slot 111 and a test slot 112, wherein the reset slot 111 is used for mounting the reset assembly 6, and the test slot 112 is used for mounting the test assembly 7. The operation plate 12 of the base 1 is provided with a pair of limiting walls 13 on both sides, and each side limiting wall 13 comprises an anti-drop wall 131 close to the operation plate 12 and a mounting wall 132 away from the operation plate 12. The height of the anti-drop wall 131 is greater than that of the mounting wall 132, and the heights of both are greater than the groove depth of the reset slot 111 and the test slot 112, forming double limiting of the assembly.

[0025] The reset assembly 6 comprises a reset button 61 and a reset spring 62 sleeved thereon. The reset slot 111 is provided with a spring mounting wall 1111 away from the operation plate 12, and a limiting slot 1112 is formed in the center thereof for the up-down movement of the reset button 61. The lower part of the spring mounting wall 1111 is provided with an inclined guide wall 1113, which facilitates the assembly of the reset button 61 with spring. The reset assembly 6 further comprises a lock plate 63, and the reset slot 111 is provided with a rotating hole 1114 and a lock plate mounting wall 1115 at the corresponding position, and the lower part of the lock plate mounting wall 1115 is also provided with a guide slope for assembly.

[0026] The test assembly 7 comprises a static contact 71, a dynamic contact 72, a test button 73 and a test spring 74. The test slot 112 is divided into a static contact placing slot 1121 and a dynamic contact placing slot 1122, and the two are separated by an insulating wall 1123. The end of the dynamic contact 72 is in an inclined structure, which forms an angle with the bending wall 1124 in the test slot 112, ensuring that the dynamic contact 72 always abuts against the test button 73. The outer sides of the static contact placing slot 1121 and the dynamic contact placing slot 1122 are provided with welding grooves 1125 for wire connection.

[0027] The inner side of the lower cover 3 is provided with a clamping wall 31 corresponding to the position of the limiting slot 1112, which comprises a positioning wall 311 embedded in the inner side of the anti-drop wall 131 and an encapsulation wall 312 flush with the mounting wall 132, and the distance between the two is matched with the thickness of the limiting wall 13 to form a precise assembly structure.

[0028] The mounting process of the embodiment is as follows: firstly, the reset button 61 with the reset spring 62 is sequentially mounted in the reset groove 111 of the base 1, the vertical guide is realized by the limiting groove 1112 of the spring mounting wall 1111, the reset assembly 6 is assembled by the aid of the inclined guide wall 1113, and the lock plate 63 is mounted in the lock plate mounting wall 1115 through the rotating hole 1114; the static contact 71 and the dynamic contact 72 with the inclined surface structure are respectively mounted in the static contact placing groove 1121 and the dynamic contact placing groove 1122 in the test groove 112, the angle of the dynamic contact 72 is constrained by the bending wall 1124 and abuts against the test button 73, the test spring 74 is mounted in the test groove 112; subsequently, the limiting wall 13 formed by the anti-disengagement wall 131 and the mounting wall 132 on both sides of the operation plate 12 is respectively precisely clamped with the positioning wall 311 and the packaging wall 312 of the lower cover 3, the wire connection is completed through the welding groove 1125, the assembly structure of double limiting and insulation isolation is formed, and finally the base 1 is detachably connected with the upper cover 2 and the lower cover 3 to complete the mounting.

[0029] The above embodiment is only one of preferred specific embodiments of the utility model, and the common changes and replacements made by the person skilled in the art within the technical scheme range of the utility model are all included in the protection range of the utility model.

Claims

1. A miniature circuit breaker, comprising a base, wherein an upper cover and a lower cover are detachably connected to both sides of the base, an operating mechanism mounting groove is formed between the base and the upper cover, and a button mounting groove is formed between the base and the lower cover, characterized in that: It also includes an integrally formed mounting base on the base, the mounting base including a reset slot for mounting a reset assembly and a test slot for mounting a test assembly, the base including an operating plate, and limiting walls located on one side of the reset slot and the test slot on both sides of the base, the limiting walls including an anti-detachment wall near the operating plate and a mounting wall away from the operating plate, the height of the anti-detachment wall and the mounting wall being greater than the depth of the reset slot and the test slot, and the height of the anti-detachment wall being greater than the height of the mounting wall.

2. The miniature circuit breaker according to claim 1, characterized in that: The reset assembly includes a reset button and a reset spring sleeved on the reset button for ejecting the reset button. The reset groove on the side away from the operation panel includes a spring mounting wall that allows the reset spring to abut against it. A limiting groove for inserting the reset button is provided at the center of the spring mounting wall. The limiting groove allows the reset button to move only up and down. The side of the spring mounting wall near the lower cover is inclined towards the direction away from the operation panel to facilitate the insertion of the reset button with the reset spring sleeved on it.

3. The miniature circuit breaker according to claim 2, characterized in that: The reset assembly also includes a locking plate that releases the lock on the reset button when the button is tripped. The side of the reset slot away from the operating panel includes a rotating hole for inserting the locking plate therein so that the locking plate can rotate around it, and a locking plate mounting wall for easy insertion of the locking plate. The side of the locking plate mounting wall near the lower cover is inclined in the direction away from the operating panel.

4. The miniature circuit breaker according to claim 1, characterized in that: The test assembly includes a stationary contact, a moving contact, a test button for driving the stationary and moving contacts into contact, and a test spring for driving the test button to reset. The test slot includes a stationary contact slot and a moving contact slot for placing the stationary and moving contacts, respectively. An insulating wall is provided between the stationary contact slot and the moving contact slot to prevent creepage between the stationary and moving contacts.

5. The miniature circuit breaker according to claim 4, characterized in that: The movable contact piece is inclined at one end near the test button. The test groove is also provided with a bent wall that matches the inclination angle of the inclined portion of the movable contact piece. The bent wall cooperates with the inclined portion of the movable contact piece so that the inclined portion of the movable contact piece always rests against the test button.

6. The miniature circuit breaker according to claim 4, characterized in that: Both the stationary contact plate placement slot and the moving contact plate placement slot are provided with welding slots for welding wires on the side away from the operation panel.

7. The miniature circuit breaker according to claim 1, characterized in that: The lower cover is provided with a locking wall corresponding to the limiting groove. The locking wall includes a positioning wall embedded inside the anti-detachment wall and an encapsulation wall that is on the same horizontal plane as the mounting wall. The distance difference between the positioning wall and the encapsulation wall is equivalent to the thickness of the limiting wall.

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