Clamping type contact mechanism and circuit breaker
By using a clamping contact structure and an arc-inducing plate design, the problems of the moving contact springing up and arcing under short-circuit current are solved, thus achieving efficient breaking and improved safety of the circuit breaker.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUIZHOU TAIYONG CHANGZHENG TECH CO LTD
- Filing Date
- 2025-04-15
- Publication Date
- 2026-05-12
AI Technical Summary
The moving contacts of existing circuit breakers are prone to springing up under the electrodynamic repulsion of short-circuit current, leading to poor contact and arcing, which affects breaking performance and safety. Furthermore, the arcing accelerates contact wear and reduces service life.
采用夹持式触头结构，结合贴合式接触和夹持式接触方式，通过夹持头与静触点的配合，防止动触头在电动斥力下脱离接触，并通过引弧片分割和拉长电弧，减少电弧产生。
It effectively prevents the moving contact from bouncing up under short-circuit current, reduces arc generation, improves the breaking performance and safety of the circuit breaker, and extends its service life.
Smart Images
Figure CN224232628U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of low-voltage electrical equipment technology, specifically relating to a clamping contact structure and a circuit breaker. Background Technology
[0002] Universal circuit breakers are used to distribute electrical energy and protect lines and power equipment from faults such as overload, undervoltage, short circuit, and single-phase grounding. In existing technology, the moving contacts of circuit breakers typically employ a snap-fit contact method. However, under the electrodynamic repulsion of short-circuit current, the moving contacts are easily snapped back momentarily, leading to poor contact and arcing, which affects the breaking performance and safety of the circuit breaker. Furthermore, the arcing accelerates contact wear, reducing the service life of the circuit breaker. Utility Model Content
[0003] To address the aforementioned problems, the purpose of this utility model is to provide a clamping contact structure and circuit breaker. This clamping contact structure and circuit breaker can effectively prevent the moving contact from being ejected and losing contact with the stationary contact under the electric repulsive force of the short-circuit current, while also reducing the generation of electric arcs.
[0004] The objective of this utility model is achieved through the following technical solution:
[0005] A clamping contact structure includes a stationary contact assembly and a moving contact assembly. The stationary contact assembly includes a busbar. The head end of the busbar is connected to a terminal, and its tail end is located near the moving contact assembly. A clamping head and a stationary contact are mounted on the top of the busbar. The clamping head is located between the middle and tail end of the busbar. The stationary contact is located at the tail end of the busbar. The top height of the clamping head is greater than the top height of the stationary contact. The moving contact assembly includes a moving contact support, a main contact, and a clamping contact. The moving contact support can drive the main contact and the clamping contact to rotate towards or away from the stationary contact. The tail ends of the main contact and the clamping contact are both mounted on the moving contact support. The head end of the clamping contact is in separate contact with the clamping head. Silver contacts that are in separate contact with the stationary contact are respectively provided at the bottom of the main contact and the clamping contact.
[0006] When the main contact and the clamping contact approach the stationary contact assembly under the action of the moving contact support, the head of the clamping contact contacts the clamping head first, and then the silver contacts on the main contact and the clamping contact contact the stationary contact.
[0007] When the main contact and the clamping contact are moved away from the stationary contact assembly by the moving contact support, the silver contacts on the main contact and the clamping contact first separate from the stationary contact, and then the head of the clamping contact contacts and separates from the clamping head.
[0008] Furthermore, the stationary contact assembly also includes an arc-inducing plate, which is installed on the top of the busbar near the clamping head, so that the clamping head is located between the arc-inducing plate and the stationary contact. This is used to divide and lengthen the arc, accelerate the cooling and deionization process of the arc, and extinguish the arc.
[0009] Furthermore, the moving contact assembly also includes a contact spring, one end of which is fixed to the moving contact bracket, and the other end is connected to the main contact and the clamping contact to provide contact pressure.
[0010] This utility model also provides a circuit breaker, including a base, a bottom plate, and at least one of the above-mentioned clamping contact structures; the base and the bottom plate are fitted together to form at least one cavity for installing the clamping contact structure, each cavity is equipped with one clamping contact structure, and adjacent cavities are spaced apart; the moving contact assembly can rotate in the cavity.
[0011] This invention combines a contact-fitting method with a clamping method, which can effectively prevent the moving contact from being bounced up by the electric repulsion force of the short-circuit current and losing contact with the stationary contact, thereby reducing the generation of electric arc and improving the breaking performance and safety of the circuit breaker. Attached Figure Description
[0012] The structure of this utility model will be further described in detail below with reference to the accompanying drawings.
[0013] Figure 1 This is an exploded structural diagram of the circuit breaker described in this utility model.
[0014] Figure 2 This is a schematic diagram of the clamping contact structure of this utility model in the closed state.
[0015] Figure 3 This is a schematic diagram of the structure of the stationary contact assembly described in this utility model.
[0016] Figure 4 This is a schematic diagram of the moving contact assembly described in this utility model.
[0017] Figure 5 This is a schematic diagram of the structure of the main contact described in this utility model.
[0018] Figure 6 This is a schematic diagram of the structure of the clamping contact described in this utility model.
[0019] Figure 7 This is a schematic diagram of the structure of the clamping head described in this utility model.
[0020] The figure shows: 1-base, 2-base plate, 3-stationary contact assembly, 31-busbar, 32-arc-starting plate, 33-clamping head, 331-contact plate, 34-stationary contact, 4-moving contact assembly, 41-moving contact bracket, 42-contact spring, 43-main contact, 44-clamping contact, 5-cavity. Detailed Implementation
[0021] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. The described embodiments are merely some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0022] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of this invention, should still fall within the scope of the technical content disclosed herein. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.
[0023] In the description of this utility model, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" or "linked" should be interpreted broadly. For example, it can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. It should be noted that the terms "comprising," "including," or any other variations are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Example 1
[0024] like Figure 1-3 As shown, this embodiment provides a clamping contact structure, including a stationary contact assembly 3 and a moving contact assembly 4.
[0025] The stationary contact assembly 3 includes a busbar 31, a clamping head 33, and a stationary contact 34.
[0026] The busbar 31 is a long strip of metal conductive plate (such as a copper plate), with wires connected at its head end and its tail end located near the moving contact assembly 4.
[0027] The clamping head 33 is installed on the top of the busbar 31 and located between the middle and tail ends of the busbar 31. The clamping head 33 is a U-shaped clamping structure composed of two contact pieces 331. The two contact pieces 331 are symmetrically arranged on the top of the busbar 31, and a guide groove is formed between the two contact pieces 331 to clamp and limit the range of motion of the clamping contact 44. The top height of the two contact pieces 331 is greater than the top height of the stationary contact 34, which gives the clamping head 33 a certain vertical depth to ensure that the clamping contact 44 can always maintain reliable contact with the clamping head 33 during the swinging process under the electric repulsion force, thereby reducing the generation of electric arc. Both contact pieces 331 are made of elastic metal sheets, and the upper inner part of both protrudes inward to form a neck on the upper part of the guide groove to ensure reliable clamping of the clamping contact 44; in addition, the bottom surface of the inner side of the guide groove is lower than the upper surface of the stationary contact 34.
[0028] The stationary contact 34 is a long strip of conductive metal sheet installed on the top of the busbar 31 and located at the tail end of the busbar 31. The top height (thickness) of the stationary contact 34 is less than the top height of the clamping head 33.
[0029] The moving contact assembly 4 includes a moving contact support 41, a main contact 43, and a clamping contact 44.
[0030] The moving contact bracket 41 is correspondingly disposed at the tail end of the stationary contact assembly 3 and can rotate under the action of an external force (circuit breaker operating mechanism). The moving contact bracket 41 can drive the main contact 43 and the clamping contact 44 to rotate toward or away from the stationary contact 34.
[0031] The tail end of the main contact 43 is mounted on a pre-set mounting shaft on the moving contact bracket 41, and a wire is connected to the tail end of the main contact 43. Silver contacts 45 are respectively provided at the bottom of the main contact 43. The main contact 43 can contact or separate from the stationary contact 34 as the moving contact bracket 41 rotates, achieving separate contact. After the silver contacts 45 of the main contact 43 contact the stationary contact 34, the head end of the main contact 43 extends out of the moving contact bracket 41 and is located between the clamping head 33 and the stationary contact 34.
[0032] The tail end of the clamping contact 44 is mounted on a pre-set mounting shaft on the moving contact bracket 41 (i.e., the tail end of the main contact 43 and the tail end of the clamping contact 44 are coaxially arranged). The tail end of the clamping contact 44 is also connected to the wire. The head end of the clamping contact 44 and the clamping head 33 can rotate into the guide groove and be clamped by the clamping head 33 under the drive of the moving contact bracket 41, or can rotate in the opposite direction and leave the guide groove of the clamping head 33 under the drive of the moving contact bracket 41, so as to realize the separation contact between the head end of the clamping contact 44 and the clamping head 33. The silver contact 45 at the bottom of the clamping contact 44 can also be separated from the stationary contact 34.
[0033] The main contact 43 and the clamping contact 44 are attached together to form a moving contact mechanism. This moving contact mechanism, together with the stationary contact 34 and a clamping head 33, constitutes a set of breaking units.
[0034] When the main contact 43 and the clamping contact 44 approach the stationary contact assembly 3 under the action of the moving contact bracket 41, the head end of the clamping contact 44 first contacts the clamping head 33, and then the silver contact 45 on the main contact 43 and the clamping contact 44 contacts the stationary contact 34.
[0035] When the main contact 43 and the clamping contact 44 move away from the stationary contact assembly 3 under the action of the moving contact support 41, the silver contact 45 on the main contact 43 and the clamping contact 44 first separates from the stationary contact 34, and then the head end of the clamping contact 44 contacts and separates from the clamping head 33. Example 2
[0036] To achieve reliable and effective contact, this embodiment differs from Embodiment 1 in that:
[0037] Each moving contact bracket 41 is equipped with two or more moving contact mechanisms. All moving contact mechanisms are parallel to each other and move synchronously under the drive of the moving contact bracket 41. Correspondingly, the number of clamping heads 33 is consistent with the number of moving contact mechanisms and corresponds one-to-one. The clamping contact 44 of each moving contact mechanism is in separate contact with its corresponding clamping head 33. Example 3
[0038] To achieve effective limiting of the main contact 43 and the clamping contact 44, the difference between this embodiment and Embodiment 1 or Embodiment 2 is as follows:
[0039] At least one mounting slot is provided at the bottom of the moving contact bracket 41. A moving contact mechanism is rotatably mounted in each mounting slot. The head end of each moving contact mechanism extends out of the mounting slot and is in separate contact with the stationary contact assembly 3. Example 4
[0040] To ensure that the silver contact 45 of each moving contact mechanism can maintain reliable contact with the stationary contact 34.
[0041] The moving contact assembly 4 also includes at least one contact spring 42, which is respectively disposed in the mounting slot. Each moving contact mechanism is connected to a contact spring 42. The upper end of the contact spring 42 is fixed to the inner top of the corresponding mounting slot in the moving contact bracket 41, and the lower end is installed on the top of the corresponding moving contact mechanism (main contact 43 and clamping contact 44) to provide contact pressure.
[0042] Meanwhile, the tail ends of the main contact 43 and the clamping contact 44 of each moving contact mechanism are rotatably mounted on the same mounting shaft preset on the moving contact bracket 41, and each moving contact mechanism also shares the same mounting shaft. The main contact 43 and the clamping contact 44 of each moving contact mechanism can rotate a certain angle within the mounting groove. When the moving contact bracket 41 rotates, causing the silver contact 45 of the main contact 43 and the clamping contact 44 to contact the stationary contact 34, the moving contact bracket 41 will continue to rotate a certain angle, compressing the contact spring 42. The elastic force of the contact spring 42 pushes the main contact 43 and the clamping contact 44 to maintain reliable contact with the stationary contact 34 respectively. When the contact spring 42 is compressed, the moving contact bracket 41 will move relative to the moving contact mechanism, that is, the moving contact mechanism rotates a certain distance in the opposite direction relative to the stationary contact assembly 3 while maintaining reliable contact with the stationary contact assembly 3. Example 5
[0043] To extinguish the generated electric arc, this embodiment differs from any of embodiments 1-4 in that:
[0044] The stationary contact assembly 3 also includes an arc-initiating plate 32, which is installed on the top of the busbar 31 near the clamping head 33, so that the clamping head 33 is located between the arc-initiating plate 32 and the stationary contact 34. This allows the arc to be divided and elongated, accelerating the cooling and deionization process of the arc, thus extinguishing it. The arc-initiating plate 32 has an arc-initiating groove longitudinally (along the length of the busbar 31) along its middle position, which helps to concentrate and guide the arc. It also has arc-initiating slots symmetrically distributed in a U-shape around the arc-initiating groove, with the openings at both ends facing the clamping head 33, which helps to increase the surface area of the arc and promote its cooling and extinguishing. An arc-initiating hole, symmetrically centered on the arc-initiating groove and located between the arc-initiating groove and the arc-initiating slot, is located at the end of the arc-initiating groove furthest from the clamping head 33, further aiding in guiding the arc. Furthermore, when the head end of the clamping contact 44 contacts the clamping head 33, the end of the head end of the clamping contact 44 is located between the clamping head 33 and the arc-starting plate 32 and is used as an arc-starting contact. Example 6
[0045] A circuit breaker includes a base 1, a base plate 2, and at least one clamping contact structure as described in any one of embodiments 1-5, forming a single-pole or multi-pole circuit breaker; the base 1 and the base plate 2 are fitted together to form at least one cavity 5 for mounting the clamping contact structure, each cavity 5 is fitted with one clamping contact structure, and adjacent cavities 5 are spaced apart; the moving contact assembly 4 can rotate in the cavity 5.
[0046] Working principle:
[0047] like Figure 2 As shown, when the moving contact assembly 4 is driven by the circuit breaker operating mechanism to rotate counterclockwise a certain angle in the enclosed cavity 5, the head end of the clamping contact 44 first contacts the clamping head 33, and then the silver contact 45 on the main contact 43 and the clamping contact 44 contacts the stationary contact 34, thus realizing the contact between the stationary contact assembly 3 and the moving contact assembly 4, and the circuit breaker closes.
[0048] When the moving contact assembly 4 rotates clockwise a certain angle within the enclosed cavity 5 under the action of the circuit breaker operating mechanism, the silver contact 45 on the main contact 43 and the clamping contact 44 first separates from the stationary contact 34, and then the head of the clamping contact 44 contacts and separates from the clamping head 33. This achieves the separation of the stationary contact assembly 3 and the moving contact assembly 4, and the circuit breaker trips.
[0049] When the circuit breaker is in the ON state (circuit breaker closed state), the main contact 43 and the clamping contact 44 are in close contact with the stationary contact assembly 3 to ensure stable current transmission. In the event of a fault current, the main contact 43 and the clamping contact 44 will be lifted by the electric repulsion force of the large current, and the silver contact 45 at their bottom will separate from the stationary contact 34. However, due to the certain depth of the clamping head 33 and the presence of the necking at the top of its guide groove, the jumping of the clamping contact 44 is restricted, thus keeping the clamping contact 44 in contact with the clamping head 33 on the stationary contact assembly 3, reducing the generation of electric arc.
[0050] Other aspects of this utility model that are not detailed herein are all conventional techniques known to those skilled in the art.
[0051] It should be noted that the terms “comprising,” “including,” or any other variations are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0052] The scope of protection of this utility model is not limited to the technical solutions disclosed in the specific embodiments. Any modifications, equivalent substitutions, improvements, etc., made to the above embodiments based on the technical essence of this utility model shall fall within the scope of protection of this utility model.
Claims
1. A clamping contact structure, comprising a stationary contact assembly (3) and a moving contact assembly (4), characterized in that: The stationary contact assembly (3) includes a busbar (31); a clamping head (33) and a stationary contact (34) are installed on the top of the busbar (31); the clamping head (33) is located between the middle and the tail end of the busbar (31); the stationary contact (34) is located at the tail end of the busbar (31); the top height of the clamping head (33) is greater than the top height of the stationary contact (34); The moving contact assembly (4) includes a moving contact bracket (41), a main contact (43), and a clamping contact (44); the moving contact bracket (41) can drive the main contact (43) and the clamping contact (44) to rotate toward or away from the stationary contact (34); the tail end of the main contact (43) and the tail end of the clamping contact (44) are both mounted on the moving contact bracket (41), the head end of the clamping contact (44) is in separate contact with the clamping head (33), and silver contacts (45) that are in separate contact with the stationary contact (34) are respectively provided at the bottom of the main contact (43) and the clamping contact (44).
2. The clamping contact structure according to claim 1, characterized in that: When the main contact (43) and the clamping contact (44) approach the stationary contact assembly (3) under the action of the moving contact support (41), the head end of the clamping contact (44) first contacts the clamping head (33), and then the silver contact (45) on the main contact (43) and the clamping contact (44) contacts the stationary contact (34). When the main contact (43) and the clamping contact (44) move away from the stationary contact assembly (3) under the action of the moving contact support (41), the silver contact (45) on the main contact (43) and the clamping contact (44) first separates from the stationary contact (34), and then the head of the clamping contact (44) contacts and separates from the clamping head (33).
3. The clamping contact structure according to claim 1, characterized in that: The stationary contact assembly (3) also includes an arc-inducing plate (32), which is installed on the top of the busbar (31) near the clamping head (33), so that the clamping head (33) is located between the arc-inducing plate (32) and the stationary contact (34), in order to divide and lengthen the arc, accelerate the cooling and deionization process of the arc, and extinguish the arc.
4. The clamping contact structure according to claim 3, characterized in that: When the head of the clamping contact (44) contacts the clamping head (33), the end of the head of the clamping contact (44) is located between the clamping head (33) and the arc-starting plate (32) and is used as an arc-starting contact.
5. The clamping contact structure according to claim 1, characterized in that: The moving contact assembly (4) also includes a contact spring (42), one end of which is fixed to the moving contact bracket (41), and the other end is connected to the main contact (43) and the clamping contact (44) to provide contact pressure.
6. The clamping contact structure according to claim 5, characterized in that: The tail end of the main contact (43) and the tail end of the clamping contact (44) are rotatably mounted on the same shaft preset on the moving contact bracket (41). The main contact (43) and the clamping contact (44) are fitted together to form a moving contact mechanism.
7. The clamping contact structure according to claim 6, characterized in that: The moving contact bracket (41) is provided with at least one mounting slot. A moving contact mechanism is rotatably installed in each cavity. The head end of each moving contact mechanism extends out of the mounting slot and is in separate contact with the stationary contact assembly (3). Correspondingly, a contact spring (42) is connected to each moving contact mechanism. The upper end of the contact spring (42) is fixed to the top of the inner side of the mounting slot, and the lower end is installed on the top of the moving contact mechanism. Correspondingly, the number of clamping heads (33) is consistent with the number of moving contact mechanisms and corresponds one-to-one. The clamping contact (44) of each moving contact mechanism is in separate contact with its corresponding clamping head (33).
8. The clamping contact structure according to claim 1, characterized in that: The clamping head (33) is a U-shaped clamping structure composed of two contact pieces (331) symmetrically arranged on the top of the busbar (31). A guide groove is formed between the two contact pieces (331) to clamp and limit the movement range of the clamping contact (44). The top height of the two contact pieces (331) is greater than the top height of the stationary contact (34).
9. The clamping contact structure according to claim 8, characterized in that: Both contact pieces (331) are made of elastic metal sheets, and the upper inner sides of both bulge inward to form a neck on the upper part of the guide groove.
10. A circuit breaker, characterized in that: It includes a base (1), a base plate (2), and at least one clamping contact structure as described in any one of claims 1-9; the base (1) and the base plate (2) are fitted together to form at least one cavity (5) for mounting the clamping contact structure, each cavity (5) is fitted with one clamping contact structure, and adjacent cavities (5) are spaced apart; the moving contact assembly (4) is rotatable in the cavity (5).