A miniature circuit breaker

Abstract

This utility model provides a miniature circuit breaker, including a handle, a connecting rod, a contact bracket, a moving contact, a stationary contact, and a tension spring. In the initial closing phase, the contact bracket and the moving contact rotate as a whole around a first axis, and the tension spring initially stores energy. After the moving contact contacts the stationary contact, the contact bracket continues to rotate around the first axis and drives the moving contact to generate relative motion through a second axis, allowing the tension spring to store energy further. In this way, only one tension spring is needed to simultaneously achieve contact bracket reset and provide overtravel contact pressure, eliminating the need for a torsion spring and a bracket reset spring, reducing material management costs, and avoiding the complex process of installing and positioning two springs separately, significantly improving assembly efficiency. Furthermore, by placing the tension spring's contact point on the side of the second axis away from the moving contact, combined with the degree of freedom of the moving contact's rotation around the second axis, the tension spring's force on the moving contact around the second axis during the overtravel phase precisely presses the moving contact against the stationary contact, ensuring reliable contact between the moving and stationary contacts.

Description

Technical Field

[0001] This utility model relates to the field of low-voltage electrical technology, specifically to a miniature circuit breaker. Background Technology

[0002] The contact mechanism of a typical miniature circuit breaker usually includes a contact support, a moving contact, and two springs. One spring is used to drive the contact support to reset, thereby realizing the opening action of the circuit breaker; the other is a torsion spring, which provides contact pressure between the moving and stationary contacts to ensure reliable contact when the circuit is closed.

[0003] Because the two independent springs need to be installed and positioned separately, the assembly process becomes extremely complex, which not only increases the difficulty of the operators' work but also significantly extends the production cycle. In addition, the design of two springs increases the number of parts and management costs, which is not conducive to the miniaturization and weight reduction of the product. Utility Model Content

[0004] Therefore, the technical problem to be solved by this utility model is to overcome the defects of complex assembly process and high production cost of the two springs in the prior art, so as to provide a small circuit breaker with low production cost.

[0005] Therefore, this utility model provides a miniature circuit breaker, including a handle, a connecting rod, a contact bracket, a moving contact, and a tension spring. The contact bracket is rotatably mounted on the housing around a first axis and has a contact mounting plate and a second axis vertically arranged on the contact mounting plate. The moving contact is mounted on the contact mounting plate and has a first through hole for inserting the first axis and a second through hole for inserting the second axis. The first through hole is an elongated hole. The moving contact also has a moving contact point that contacts the stationary contact and a hook point connected to one end of the tension spring. The hook point is located at the first... The two perforations are located on the side away from the moving contact; a tension spring is connected at one end to the moving contact and at the other end to the housing; in the initial closing phase, both the contact support and the moving contact rotate around the first axis, and the contact support drives the moving contact to rotate through the second axis, with the tension spring in the first energy storage state; after the moving contact contacts the stationary contact, the contact support continues to rotate around the first axis and drives the moving contact to move through the second axis, the first axis moves relative to the first perforation of the moving contact, and the moving contact can rotate relative to the contact support around the second axis, with the tension spring in the second energy storage state.

[0006] A stop is provided on the outer wall of the second shaft away from the contact mounting plate. The moving contact is formed with a third through hole that communicates with the second through hole and allows the stop to pass through. The moving contact has a pre-installation position and an assembly position that is rotated a certain angle relative to the pre-installation position. In the pre-installation position, the second shaft is inserted into the second through hole and the stop is inserted into the third through hole. In the assembly position, the stop and the third through hole are offset and abut against the side of the moving contact away from the contact mounting plate.

[0007] The contact mounting plate is formed with a fourth through hole for the first shaft to pass through. In the pre-installation position, the fourth through hole is staggered from the first through hole; in the assembly position, the fourth through hole is corresponding to the first through hole, and the first shaft passes through the first through hole and the fourth through hole in sequence.

[0008] The fourth perforation has a flared opening at the front end for the insertion direction of the first shaft.

[0009] Both the second shaft and the stop block have chamfered edges on the side away from the contact mounting plate.

[0010] The second shaft, stop block, and contact mounting plate are integrally molded by injection molding.

[0011] The moving contact has a fifth through hole at the hook point for attaching the hook at one end of the tension spring.

[0012] The fifth perforation is located between the first and second perforations.

[0013] The technical solution of this utility model has the following advantages: 1. The miniature circuit breaker provided by this utility model includes a contact bracket, a moving contact, and a tension spring. The contact bracket is rotatably mounted on the housing around a first axis and has a contact mounting plate and a second axis vertically arranged on the contact mounting plate. The moving contact is mounted on the contact mounting plate and has a first through hole for the first axis to be inserted and a second through hole for the second axis to be inserted. In the initial closing phase, the contact bracket and the moving contact rotate as a whole around the first axis, and the tension spring initially stores energy. After the moving contact contacts the stationary contact (overtravel phase), the contact bracket continues to rotate around the first axis and drives the moving contact to generate relative motion through the second axis, and the tension spring stores energy to a deeper level. When opening, the tension spring releases energy and simultaneously drives the moving contact and the contact bracket to reset. In this way, only one tension spring can simultaneously achieve the reset of the contact bracket and the provision of overtravel contact pressure, eliminating the need for a separate torsion spring and an additional bracket reset spring, reducing material management costs, and avoiding the need for two springs to be installed, positioned, and adjusted separately. The complex process significantly improves assembly efficiency and is superior to traditional structures in terms of resetting force utilization. Furthermore, by placing the tension spring contact point on the side of the second shaft away from the moving contact, combined with the moving contact's freedom of rotation around the second shaft, the tension spring's torque on the moving contact around the second shaft during the overtravel phase presses the moving contact firmly against the stationary contact, ensuring reliable contact between them. In addition, by designing the first through-hole of the moving contact as an elongated hole, the first shaft can move relative to the stationary contact after the moving contact contacts the stationary contact and the contact support continues to rotate, further stretching the tension spring (from the first energy storage state to the second energy storage state). This structure provides a larger and more stable initial contact pressure. Simultaneously, the elongated hole effectively controls the moving contact's turning space, preventing excessive final contact pressure. This solves the problem of traditional structures where a larger initial pressure leads to excessive final pressure, affecting electrical life and breaking capacity.

[0014] 2. The miniature circuit breaker provided by this utility model has a stop block on the outer wall of the second shaft away from the contact mounting plate. The moving contact is formed with a third through hole that communicates with the second through hole and allows the stop block to pass through. The moving contact has a pre-installation position and an assembly position that is rotated a certain angle relative to the pre-installation position. In the pre-installation position, the second shaft is inserted into the second through hole and the stop block is inserted into the third through hole. In the assembly position, the stop block is staggered from the third through hole and abuts against the side of the moving contact away from the contact mounting plate, thus realizing the rapid pre-assembly of the moving contact and the contact support.

[0015] 3. The miniature circuit breaker provided by this utility model has its fourth through hole offset from the first through hole during the pre-installation stage. When the moving contact rotates to the position, the fourth through hole and the first through hole are aligned. At this time, the first shaft is inserted. The first shaft not only completes the function of the rotating shaft, but also prevents the moving contact from rotating back from the assembly position to the pre-installation position, effectively preventing the moving contact from separating from the contact support, thereby playing the role of a locking pin. Compared with the traditional torsion spring assembly method, no additional retaining rings, riveting or complex tooling is required, which significantly improves the speed and convenience of assembly.

[0016] 4. In the miniature circuit breaker provided by this utility model, the fifth through hole is located between the first through hole and the second through hole, so that the lever arm of the tension spring is moderate, and the tension spring does not interfere with the first shaft and the second shaft during the movement, resulting in smoother operation. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the miniature circuit breaker of this utility model; Figure 2 This is a schematic diagram of a miniature circuit breaker in the open state; Figure 3 A schematic diagram showing the structure where the moving contact just comes into contact with the stationary contact; Figure 4 A schematic diagram of the structure where the moving contact is in the overtravel position; Figure 5 This is a schematic diagram of the assembly of the contact support and the moving contact; Figure 6 This is a 3D view of the contact support; Figure 7 A three-dimensional view of the moving contact; Figure 8 A schematic diagram of the structure with the moving contact in the pre-installation position; Figure 9 This is a schematic diagram of the moving contact in the assembly position.

[0019] Explanation of reference numerals in the attached drawings: 1. Contact bracket; 10. Contact mounting plate; 11. First shaft; 12. Second shaft; 13. Stop; 14. Fourth through hole; 15. Flared mouth; 16. Chamfer; 2. Housing; 3. Moving contact; 30. Moving contact point; 31. First through hole; 32. Second through hole; 33. Third through hole; 35. Fifth through hole; 4. Tension spring; 5. Stationary contact; 6. Handle; 7. Connecting rod. Detailed Implementation

[0020] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0024] Example This embodiment provides a miniature circuit breaker, such as Figure 1As shown, it includes a handle 6, a connecting rod 7, a contact bracket 1, a moving contact 3, a stationary contact 5, and a tension spring 4.

[0025] The handle 6 is rotatably mounted on the housing 2. One end of the connecting rod 7 is connected to the handle 6, and the other end is connected to the contact bracket 1.

[0026] Contact bracket 1 is rotatably mounted on housing 2 about first axis 11, as follows: Figure 2 and Figure 5 As shown, it has a contact mounting plate 10 and a second shaft 12 vertically disposed on the contact mounting plate 10. Figure 6 As shown, a stop block 13 is provided on the outer wall of the second shaft 12 away from the contact mounting plate 10. Both the second shaft 12 and the stop block 13 have chamfers 16 formed on the side away from the contact mounting plate 10. In this embodiment, the second shaft 12, the stop block 13 and the contact mounting plate 10 are integrally formed by injection molding.

[0027] The moving contact 3 is mounted on the contact mounting plate 10, such as... Figure 2 and Figure 7 As shown, it has a first through hole 31 for inserting the first shaft 11 and a second through hole 32 for inserting the second shaft 12. The first through hole 31 is an elongated hole. The moving contact 3 is also formed with a moving contact point 30 that contacts the stationary contact 5 and a hook point connected to one end of the tension spring 4. The hook point is located on the side of the second through hole 32 away from the moving contact point 30. In this embodiment, the hook point of the moving contact 3 is provided with a fifth through hole 35 for hooking the hook of one end of the tension spring 4. The fifth through hole 35 is located between the first through hole 31 and the second through hole 32. The moving contact 3 is formed with a third through hole 33 that communicates with the second through hole 32 and through which the stop block 13 passes. The moving contact 3 has the following characteristics: Figure 8 The pre-installation position shown, and the assembly position rotated at a certain angle relative to the pre-installation position (e.g., Figure 9 As shown); in this embodiment, the contact mounting plate 10 is formed with a fourth through hole 14 for the first shaft 11 to pass through, and the front end of the fourth through hole 14 in the insertion direction of the first shaft 11 is provided with a flared mouth 15.

[0028] As an alternative implementation, the moving contact 3 is provided with a connecting post at the hook point for the hook of one end of the tension spring 4 to be attached.

[0029] Among them, in such Figure 8 In the pre-installation position shown, the second shaft 12 is inserted into the second through hole 32, and the stop block 13 is inserted into the third through hole 33. At this time, the fourth through hole 14 is offset from the first through hole 31; the moving contact 3 rotates clockwise relative to the contact bracket 1, when... Figure 9In the assembly position shown, the fourth through hole 14 is aligned with the first through hole 31. The first shaft 11 is passed through the first through hole 31 and the fourth through hole 14 in sequence. At this time, the stop block 13 is offset from the third through hole 33 and abuts against the side of the moving contact 3 away from the contact mounting plate 10. The first shaft 11 not only performs the function of a rotating shaft, but also prevents the moving contact 3 from rotating back from the assembly position to the pre-installation position, effectively preventing the moving contact 3 from separating from the contact bracket 1, thereby acting as a locking pin. Compared with the traditional torsion spring assembly method, no additional retaining rings, riveting, or complex tooling is required, significantly improving the speed and convenience of assembly.

[0030] The tension spring 4 is connected at one end to the moving contact 3 and at the other end to the housing 2.

[0031] In the initial closing phase (before the moving contact 3 contacts the stationary contact 5), both the contact support 1 and the moving contact 3 rotate around the first axis 11, and the contact support 1 drives the moving contact 3 to move synchronously via the second axis 12, with the tension spring 4 in a first energy storage state; after the moving contact 30 of the moving contact 3 contacts the stationary contact 5 (overtravel phase), as... Figure 3 and Figure 4 As shown, the contact support 1 continues to rotate around the first axis 11 and drives the moving contact 3 to move through the second axis 12. Since the moving contact 30 abuts against the stationary contact 5, the moving contact 3 will rotate relative to the contact support 1 around the second axis 12 during the process of following the movement of the contact support 1. The first axis 11 moves relative to the first through hole 31 of the moving contact, and the tension spring 4 is in the second energy storage state.

[0032] The miniature circuit breaker provided by this utility model includes a contact support 1, a moving contact 3, and a tension spring 4. The contact support 1 is rotatably mounted on the housing 2 around a first shaft 11, and has a contact mounting plate 10 and a second shaft 12 vertically arranged on the contact mounting plate 10. The moving contact 3 is mounted on the contact mounting plate 10, and has a first through hole 31 for the first shaft 11 to be inserted and a second through hole 32 for the second shaft 12 to be inserted. In the initial closing phase, the contact support 1 and the moving contact 3 rotate as a whole around the first shaft, and the tension spring 4 initially stores energy. After the stationary contact 5 makes contact (overtravel stage), the contact support 1 continues to rotate around the first axis 11, and drives the moving contact 3 to generate relative motion through the second axis 12, while the tension spring 4 stores energy at its depth. During opening, the tension spring 4 releases energy, simultaneously driving the moving contact 3 and the contact support 1 to reset. Thus, only one tension spring 4 is needed to simultaneously achieve contact support reset and overtravel contact pressure provision, eliminating the need for a separate torsion spring and an additional support reset spring. This reduces material management costs and avoids the complex process of installing, positioning, and adjusting two springs separately, significantly improving efficiency. This design improves assembly efficiency and is superior to traditional structures in terms of resetting force utilization. Furthermore, by placing the contact point of the tension spring 4 on the side of the second shaft 12 away from the moving contact 30, and considering the degree of freedom of the moving contact 3 to rotate around the second shaft 12, the tension spring 4, during the overtravel phase, exerts its torque on the moving contact 3 around the second shaft 12, precisely pressing the moving contact 30 against the stationary contact 5, ensuring reliable contact between the moving contact 3 and the stationary contact 5. Additionally, by designing the first through hole 31 of the moving contact 3 as an elongated hole, after the moving contact 3 contacts the stationary contact 5, the contact support... 1. As the rotation continues, the first shaft 11 can move relative to the elongated hole, causing the tension spring 4 to be further stretched (from the first energy storage state to the second energy storage state). This structure can provide a larger and more stable initial contact pressure (that is, when the moving contact and the stationary contact just make contact). At the same time, due to the restriction of the elongated hole, the turning space of the moving contact can be effectively controlled, so that the final contact pressure is not too large (that is, when the moving contact and the stationary contact just make final contact). This solves the shortcomings of the traditional structure, which is that if a larger initial pressure is desired, the final pressure will be too large, affecting the electrical life and breaking capacity.

[0033] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A miniature circuit breaker, characterized in that, Includes handle (6), connecting rod (7), contact bracket (1), moving contact (3) and tension spring (4); The contact support (1) is rotatably mounted on the housing (2) about a first axis (11), and has a contact mounting plate (10) and a second axis (12) perpendicularly disposed on the contact mounting plate (10). The moving contact (3) is mounted on the contact mounting plate (10) and has a first through hole (31) for the first shaft (11) to be inserted and a second through hole (32) for the second shaft (12) to be inserted. The first through hole (31) is an elongated hole. The moving contact (3) is also formed with a moving contact point (30) that contacts the stationary contact (5) and a hook point connected to one end of the tension spring (4). The hook point is located on the side of the second through hole (32) away from the moving contact point (30). A tension spring (4) has one end connected to the moving contact (3) and the other end connected to the housing (2); In the initial stage of closing, both the contact support (1) and the moving contact (3) rotate around the first axis (11), and the contact support (1) drives the moving contact (3) to rotate through the second axis (12), and the tension spring (4) is in the first energy storage state; after the moving contact (3) contacts the stationary contact (5), the contact support (1) continues to rotate around the first axis (11), and drives the moving contact (3) to move through the second axis (12), the first axis (11) moves relative to the first through hole (31) of the moving contact, and the moving contact (3) can rotate relative to the contact support (1) around the second axis (12), and the tension spring (4) is in the second energy storage state.

2. The miniature circuit breaker according to claim 1, characterized in that, The second shaft (12) has a stop (13) on the outer wall of the side away from the contact mounting plate (10). The moving contact (3) is formed with a third through hole (33) that communicates with the second through hole (32) and allows the stop (13) to pass through. The moving contact (3) has a pre-installation position and an assembly position that is rotated a certain angle relative to the pre-installation position. In the pre-installation position, the second shaft (12) is inserted into the second through hole (32), and the stop (13) is inserted into the third through hole (33). In the assembled position, the stop (13) is offset from the third through hole (33) and abuts against the side of the moving contact (3) away from the contact mounting plate (10).

3. The miniature circuit breaker according to claim 2, characterized in that, The contact mounting plate (10) is formed with a fourth through hole (14) for the first shaft (11) to pass through. In the pre-installation position, the fourth through hole (14) is offset from the first through hole (31). In the assembly position, the fourth through hole (14) is corresponding to the first through hole (31), and the first shaft (11) passes through the first through hole (31) and the fourth through hole (14) in sequence.

4. The miniature circuit breaker according to claim 3, characterized in that, The fourth through hole (14) has a flared opening (15) at the front end of the first shaft (11) in the insertion direction.

5. The miniature circuit breaker according to claim 2, characterized in that, The second shaft (12) and the stop (13) both have chamfers (16) on the side away from the contact mounting plate (10).

6. The miniature circuit breaker according to claim 2, characterized in that, The second shaft (12), the stop block (13), and the contact mounting plate (10) are integrally formed by injection molding.

7. The miniature circuit breaker according to claim 1, characterized in that, The moving contact (3) is provided with a fifth through hole (35) at the hook point for hooking one end of the tension spring (4).

8. The miniature circuit breaker according to claim 7, characterized in that, The fifth perforation (35) is located between the first perforation (31) and the second perforation (32).

Images