Clamping type contact structure and circuit breaker
By setting clamping heads and silver contacts on the static contact assembly and movable contact assembly of the circuit breaker, combined with the bonding and clamping contacts, the problem of the dynamic contact being bounced under the action of short-circuit current is solved, the generation of arcs is reduced, and the performance and safety of the circuit breaker are improved.
Patent Information
- Application Number
- CN202510468207.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-15
- Publication Date
- 2025-06-10
AI Technical Summary
The moving contacts of existing circuit breakers are easily bounced under the action of the electric repulsion of short circuit current, resulting in poor contact and arcing, affecting the breaking performance and safety of the circuit breaker, and the arcing generates accelerates the wear of the contacts and reduces service life.
The clamping contact structure is adopted. By installing the clamping head and the static contact on the static contact assembly, and setting the main contact and the clamping contact on the static contact assembly, combining the bonding contact and the clamping contact method, the moving contact prevents the movable contact from being bounced up under the action of a short circuit current and reduces the generation of arcs.
Effectively prevent the moving contact from the static contact from the static contact, reduce the generation of arcs, improve the breaking performance and safety of the circuit breaker, and extend the service life.
Smart Images
Figure CN120126977A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of low-voltage electrical equipment, and particularly relates to a clamping type contact structure and a circuit breaker. Background Art
[0002] Universal circuit breakers are used for distributing electric energy and protecting circuits and power supply equipment from the hazards of overload, undervoltage, short circuit, single-phase grounding and other faults. In the prior art, the moving contact of a circuit breaker usually adopts a clapping contact method. However, under the action of the electro-dynamic repulsion force of short-circuit current, the moving contact is easily bounced up instantaneously, resulting in poor contact and the generation of electric arcs, which affects the breaking performance and safety of the circuit breaker. In addition, the generation of electric arcs will also accelerate the wear of the contacts and reduce the service life of the circuit breaker. Summary of the Invention
[0003] To solve the above problems, the object of the present invention is to provide a clamping type contact structure and a circuit breaker, which can effectively prevent the situation that the moving contact is bounced up under the electro-dynamic repulsion force of short-circuit current and separated from the static contact, and at the same time reduce the generation of electric arcs.
[0004] The object of the present invention is achieved by the following technical solutions: A clamping type contact structure includes a static contact assembly and a moving contact assembly. The static contact assembly includes a busbar; the head end of the busbar is wired, and its tail end is arranged close to the moving contact assembly. A clamping head and a static contact are installed on the top of the busbar; the clamping head is located between the middle and the tail end of the busbar; the static 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 static contact; the moving contact assembly includes a moving contact bracket, a main contact and a clamping type contact; the moving contact bracket can drive the main contact and the clamping type contact to rotate towards or away from the static contact; the tail ends of the main contact and the clamping type contact are both installed on the moving contact bracket, the head end of the clamping type contact is in separable contact with the clamping head, and silver contacts in separable contact with the static contact are respectively arranged at the bottoms of the main contact and the clamping type contact.
[0005] When the main contact and the clamping type contact are driven by the moving contact bracket to approach the static contact assembly, the head end of the clamping type contact first contacts the clamping head, and then the silver contacts on the main contact and the clamping type contact contact the static contact.
[0006] When the main contact and the clamping type contact are driven by the moving contact bracket to move away from the static contact assembly, the silver contacts on the main contact and the clamping type contact first separate from the static contact, and then the head end of the clamping type contact contacts and separates from the clamping head.
[0007] Further, the static contact assembly further includes an arcing piece, which is installed at the top of the busbar near the clamping head, with the clamping head located between the arcing piece and the static contact, and is used to split and elongate the arc, accelerate the cooling and deionization process of the arc, and achieve the extinction of the arc.
[0008] Further, the moving contact assembly further includes a contact spring. One end of the contact spring is fixed on the moving contact bracket, and the other end is connected to the main contact and the clamping contact, and is used to provide contact pressure.
[0009] The present invention also provides a circuit breaker, which includes a base, a bottom plate, and at least one of the above-mentioned clamping contact structures; the base and the bottom plate are cooperatively installed to form at least one cavity for installing the clamping contact structure, each cavity installs one clamping contact structure, and adjacent cavities are separated; the moving contact assembly can rotate in the cavity.
[0010] The present invention combines the clamping contact method on the basis of the fitting contact, which can effectively prevent the moving contact from being bounced up by the electrodynamic repulsive force of the short-circuit current and disengaging from the static contact, reduce the generation of arcs, and improve the breaking performance and safety of the circuit breaker. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The following further describes the structure of the present invention in detail with reference to the drawings.
[0012] Figure 1 It is an exploded structure diagram of the circuit breaker described in the present invention.
[0013] Figure 2 It is a schematic structural diagram of the clamping contact structure described in the present invention in the closed state.
[0014] Figure 3 It is a schematic structural diagram of the static contact assembly described in the present invention.
[0015] Figure 4 It is a schematic structural diagram of the moving contact assembly described in the present invention.
[0016] Figure 5 It is a schematic structural diagram of the main contact described in the present invention.
[0017] Figure 6 It is a schematic structural diagram of the clamping contact described in the present invention.
[0018] Figure 7 It is a schematic structural diagram of the clamping head described in the present invention.
[0019] As shown in the figure: 1 - base, 2 - bottom plate, 3 - static contact assembly, 31 - bus bar, 32 - arc - guiding piece, 33 - clamping head, 331 - contact piece, 34 - static contact, 4 - moving contact assembly, 41 - moving contact support, 42 - contact spring, 43 - main contact, 44 - clamping - type contact, 5 - cavity. Detailed implementation manners
[0020] The following specific embodiments illustrate the implementation manners of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The described embodiments are only a part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.
[0021] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the limiting conditions under which the present invention can be implemented. Therefore, they do not have technical essential significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the effects that the present invention can produce and the purposes that can be achieved, should still fall within the scope covered by the technical content disclosed in the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" cited in this specification are only for the convenience of description and clarity, rather than used to limit the scope under which the present invention can be implemented. The change or adjustment of their relative relationships, without substantial change in the technical content, should also be regarded as the scope within which the present invention can be implemented.
[0022] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above - mentioned terms in the present invention can be understood according to specific situations. It should be noted that the terms "include", "comprise" or any other variant are intended to cover non - exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such a process, method, article or device. Embodiment 1
[0023] As Figure 1-3 shown, this embodiment provides a clamping - type contact structure, including a static contact assembly 3 and a moving contact assembly 4.
[0024] The static contact assembly 3 includes a bus bar 31, a clamping head 33, and a static contact 34.
[0025] The bus bar 31 is a long strip-shaped metal conductive plate (such as a copper plate), with its head end connected to a wire, and its tail end is arranged close to the moving contact assembly 4.
[0026] The clamping head 33 is installed on the top of the bus bar 31 and is located between the middle and the tail end of the bus bar 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 bus bar 31. A guiding groove for clamping and restricting the movement range of the clamping contact 44 is formed between the two contact pieces 331. The top height of the two contact pieces 331 is greater than the top height of the static contact 34, which makes the clamping head 33 have a certain vertical depth, so as to ensure that the clamping contact 44 can always maintain reliable contact with the clamping head 33 during the swinging process under the action of the electro-dynamic repulsion force, thereby reducing the generation of electric arcs. Both contact pieces 331 are made of elastic metal sheets, and the upper inner sides of the two contact pieces 331 bulge inward to form a constriction part at the upper part of the guiding groove to ensure reliable clamping of the clamping contact 44; in addition, the bottom surface height of the inner side of the guiding groove is lower than the upper surface height of the static contact 34.
[0027] The static contact 34 is a long strip-shaped conductive metal sheet installed on the top of the bus bar 31 and located at the tail end of the bus bar 31. The top height (thickness) of the static contact 34 is less than the top height of the clamping head 33.
[0028] The moving contact assembly 4 includes a moving contact bracket 41, a main contact 43, and a clamping contact 44.
[0029] The moving contact bracket 41 is correspondingly arranged at the tail end of the static contact assembly 3 and can rotate under the drive 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 towards or away from the static contact 34.
[0030] The tail end of the main contact 43 is installed on a preset 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 arranged at the bottom of the main contact 43. The main contact 43 can contact or separate from the static contact 34 as the moving contact bracket 41 rotates, realizing separated contact. After the silver contact 45 of the main contact 43 contacts the static 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 static contact 34.
[0031] The tail end of the clamping contact 44 is installed on a preset mounting shaft on the moving contact bracket 41 (that is, the tail end of the main contact 43 is coaxially arranged with the tail end of the clamping contact 44), and the tail end of the clamping contact 44 is also connected to the wire at the same time. The head end of the clamping contact 44 and the clamping head 33 can be driven by the moving contact bracket 41 to rotate into the guide groove and be clamped by the clamping head 33, or can be driven by the moving contact bracket 41 to rotate in the opposite direction to leave the guide groove of the clamping head 33, so as to realize the separate contact between the head end of the clamping contact 44 and the clamping head 33, and the silver contact 45 at the bottom of the clamping contact 44 can also be separately contacted with the static contact 34.
[0032] The main contact 43 and the clamping contact 44 are fitted together to form a moving contact mechanism, and the moving contact mechanism cooperates with the static contact 34 and a clamping head 33 to form a set of disconnecting units.
[0033] When the main contact 43 and the clamping contact 44 approach the stationary contact assembly 3 driven by the moving contact bracket 41 , the head end of the clamping contact 44 first contacts the clamping head 33 , and then the silver contacts 45 on the main contact 43 and the clamping contact 44 contact the stationary contact 34 .
[0034] When the main contact 43 and the clamping contact 44 are driven away from the stationary contact assembly 3 by the moving contact bracket 41, the silver contacts 45 on the main contact 43 and the clamping contact 44 are first separated from the stationary contact 34, and the head end of the clamping contact 44 then contacts and separates from the clamping head 33. Example 2
[0035] To achieve reliable and effective contact, the difference between this embodiment and embodiment 1 is that: There are two or more moving contact mechanisms installed on each moving contact bracket 41, all of which are parallel to each other and move synchronously driven by 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, and the clamping contact 44 of each moving contact mechanism is in separate contact with its corresponding clamping head 33. Example 3
[0036] In order to effectively limit the main contact 43 and the clamping contact 44, the difference between this embodiment and embodiment 1 or embodiment 2 is as follows: At least one mounting groove is provided at the bottom of the moving contact bracket 41 , and a moving contact mechanism is rotatably mounted in each mounting groove. The head end of each moving contact mechanism extends out of the mounting groove and is in separate contact with the stationary contact assembly 3 . Example 4
[0037] To ensure that the silver contact 45 of each moving contact mechanism can maintain reliable contact with the static contact 34.
[0038] The moving contact assembly 4 further includes at least one contact spring 42, which is respectively arranged in the installation groove in a one-to-one correspondence. One contact spring 42 is connected to each moving contact mechanism. The upper end of the contact spring 42 is fixed to the inner top of the corresponding installation groove in the moving contact bracket 41, and the lower end is installed on the top of the corresponding moving contact mechanism (on the main contact 43 and the clamping contact 44) for providing contact pressure.
[0039] At the same time, the tail ends of the main contact 43 and the clamping contact 44 on each moving contact mechanism are rotatably installed on the same installation shaft preset on the moving contact bracket 41, and each moving contact mechanism also shares the same installation shaft. The main contact 43 and the clamping contact 44 of each moving contact mechanism can rotate a certain angle in the installation groove. When the moving contact bracket 41 rotates and the silver contacts 45 of the main contact 43 and the clamping contact 44 contact the static contact 34, the moving contact bracket 41 will continue to rotate a certain angle to compress the contact spring 42. Through the elastic force of the contact spring 42, the main contact 43 and the clamping contact 44 are respectively pushed to keep reliable contact with the static contact 34. When the contact spring 42 is compressed, relative movement will occur between the moving contact bracket 41 and the moving contact mechanism, that is, the moving contact mechanism rotates a certain distance in the opposite direction relative to the installation groove while maintaining reliable contact with the static contact assembly 3. Embodiment 5
[0040] To achieve the extinction of the generated arc, the difference between this embodiment and any one of Embodiments 1-4 is that: The static contact assembly 3 further includes an arc guide piece 32, which is installed at the top of the bus bar 31 near the clamping head 33, so that the clamping head 33 is located between the arc guide piece 32 and the static contact 34, and is used to divide and lengthen the arc, accelerate the cooling and deionization process of the arc, and achieve the extinction of the arc. The arc guide piece 32 is longitudinally provided with an arc guide groove (in the length direction of the bus bar 31) at the middle position of the arc guide piece 32, which helps to concentrate and guide the arc; it is also provided with arc guide slots that are symmetrically distributed with the arc guide groove as the center and are U-shaped. The two ends of the arc guide slots are open and face the clamping head 33, which helps to increase the surface area of the arc and promote the cooling and extinction of the arc; the arc guide holes are centered on the arc guide groove and are located between the arc guide groove and the arc guide slots. The arc guide holes are located at the end of the arc guide groove away from the clamping head 33, which further helps to guide the arc. In addition, 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 guide piece 32 and is used as an arc guide contact. Embodiment 6
[0041] A circuit breaker comprises a base 1, a bottom plate 2 and at least one clamping contact structure as described in any one of embodiments 1-5, constituting a single-pole or multi-pole circuit breaker; the base 1 and the bottom plate 2 are installed in cooperation to form at least one cavity 5 for installing the clamping contact structure, each cavity 5 is installed with a clamping contact structure, and adjacent cavities 5 are separated; the moving contact assembly 4 can rotate in the cavity 5. Working principle:
[0042] like Figure 2 As shown, when the moving contact assembly 4 rotates counterclockwise by a certain angle in the closed cavity 5 driven by the circuit breaker operating mechanism, 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 static contact 34, that is, the static contact assembly 3 and the moving contact assembly 4 are in contact, and the circuit breaker is closed.
[0043] When the moving contact assembly 4 rotates clockwise by a certain angle in the closed cavity 5 driven by the circuit breaker operating mechanism, the silver contacts 45 on the main contact 43 and the clamping contact 44 are separated from the stationary contact 34 first, and then the head end of the clamping contact 44 is separated from the clamping head 33. That is, the stationary contact assembly 3 and the moving contact assembly 4 are separated, and the circuit breaker is opened.
[0044] 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 static contact assembly 3 to ensure the stable transmission of current. In the case of a fault current, the main contact 43 and the clamping contact 44 will be bounced up under the large current electromotive repulsion, and the silver contact 45 at the bottom of both will be separated from the static contact 34. However, since the clamping head 33 has a certain depth and the neck portion at the upper part of its guide groove exists, the jumping of the clamping contact 44 is limited, so that the clamping contact 44 still maintains contact with the clamping head 33 on the static contact assembly 3, reducing the generation of arcs.
[0045] Other aspects of the present invention that are not described in detail are all conventional techniques known to those skilled in the art.
[0046] It should be noted that the terms "comprises", "includes" or any other variations are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.
[0047] The protection scope of the present invention is not limited to the technical solutions disclosed in the specific implementation methods. Any modifications, equivalent replacements, improvements, etc. made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the present invention.
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) comprises a busbar (31); a clamping head (33) and a stationary contact (34) are mounted 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) comprises a moving contact support (41), a main contact (43) and a clamping contact (44); the moving contact support (41) can drive the main contact (43) and the clamping contact (44) to rotate in a direction approaching 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 support (41), the head end of the clamping contact (44) is in separate contact with the clamping head (33), and silver contacts (45) are respectively provided at the bottom of the main contact (43) and the clamping contact (44) for separate contact with the stationary contact (34).
2. The clamping contact structure according to claim 1, characterized in that: When the main contact (43) and the clamping contact (44) are driven by the moving contact support (41) to approach the stationary contact assembly (3), the head end of the clamping contact (44) first contacts the clamping head (33), and then the silver contacts (45) on the main contact (43) and the clamping contact (44) contact the stationary contact (34); When the main contact (43) and the clamping contact (44) are driven by the moving contact support (41) to move away from the stationary contact assembly (3), the silver contacts (45) on the main contact (43) and the clamping contact (44) are first separated from the stationary contact (34), and the head end of the clamping contact (44) is then separated from the clamping head (33).
3. The clamping contact structure according to claim 1, characterized in that: The stationary contact assembly (3) further comprises an arc-striking piece (32), which is mounted on the top of the busbar (31) near a clamping head (33), so that the clamping head (33) is located between the arc-striking piece (32) and the stationary contact (34), and is used to split and lengthen the arc, accelerate the cooling and deionization process of the arc, and achieve extinguishing of the arc.
4. The clamping contact structure according to claim 3, characterized in that: 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 striking piece (32) and is used as an arc striking contact.
5. The clamping contact structure according to claim 1, characterized in that: The moving contact assembly (4) further comprises a contact spring (42), one end of the contact spring (42) being fixed to the moving contact support (41), and the other end of the contact spring (42) being connected to the main contact (43) and the clamping contact (44) for providing 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 both rotatably mounted on the same axis preset on the moving contact support (41), and 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 groove, and a moving contact mechanism is rotatably mounted in each cavity, and the head end of each moving contact mechanism extends out of the mounting groove and is in separate contact with the stationary contact assembly (3). Correspondingly, a contact spring (42) is connected to each moving contact mechanism, and the upper end of the contact spring (42) is fixed to the top of the inner side of the mounting groove, and the lower end is mounted on the top of the moving contact mechanism; correspondingly, the number of the clamping heads (33) is consistent with the number of the moving contact mechanisms and corresponds one to one, and 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 for clamping and limiting the movement range of the clamping contact (44) is formed between the two contact pieces (331); the top height of the two contact pieces (331) is greater than the top height of the static contact (34).
9. The clamping contact structure according to claim 8, characterized in that: The two contact sheets (331) are both made of elastic metal sheets, and the inner upper parts of the two contact sheets protrude inwards to form a neck portion at the upper part of the guide groove.
10. A circuit breaker, characterized in that: It comprises a base (1), a bottom plate (2) and at least one clamping contact structure as claimed in any one of claims 1 to 9; the base (1) and the bottom plate (2) are installed in cooperation to form at least one cavity (5) for installing the clamping contact structure, each cavity (5) is installed with a clamping contact structure, and adjacent cavities (5) are spaced apart; the moving contact assembly (4) can rotate in the cavity (5).