A contact arc extinguishing system for a switch

Abstract

An arc-extinguishing system for a switch belongs to the field of low-voltage electrical technology. It includes an arc-extinguishing chamber and a contact system. The contact system includes a moving contact and a stationary contact. After the moving contact actuates, it makes contact with or separates from the stationary contact. The arc-extinguishing chamber is located on one side of the contact system in the opening direction. The arc-extinguishing chamber includes a pair of side plates, multiple grid plates disposed between the pair of side plates, and a pair of gas-generating elements. The pair of gas-generating elements are located at the lower edge of the grid plates. The key feature is that the pair of gas-generating elements are arranged opposite each other, forming a flared opening with a larger diameter at the bottom and a smaller diameter at the top in the upward direction. The moving contact includes a long contact plate and a short contact plate, with the arc-initiating head of the long contact plate extending beyond the flared opening. Advantages: It helps the arc quickly cross the flared opening, facilitates the arc's rapid entry into the grid plates of the arc-extinguishing chamber, and effectively prevents arc retreat.

Description

Technical Field

[0001] This utility model belongs to the field of low-voltage electrical technology, specifically relating to a contact arc extinguishing system for a switch. Background Technology

[0002] Switches are crucial electrical appliances in power supply and distribution lines. They interrupt the current carrying the circuit, protecting the lines and electrical equipment. A switch typically includes a contact system, which consists of moving and stationary contacts. When the moving contact actuates, it contacts or separates from the stationary contact, thus enabling the switch to conduct or disconnect. As is known in the industry, when a switch breaks, an electric arc is generated between the moving and stationary contacts. Due to the relatively large energy of the arc, breaking the switch becomes extremely difficult. Therefore, switches usually include an arc-extinguishing chamber to extinguish the arc generated when the moving and stationary contacts separate. The circuit is only broken when the arc is extinguished. The role of the arc-extinguishing chamber in ensuring the safe operation of electrical equipment is undeniable.

[0003] In existing technology, the moving contact includes a long contact piece and a short contact piece. The long contact piece extends into the flared opening of the arc-extinguishing chamber, thereby enabling the arc to be quickly centered. This allows the arc to enter the grid plate more rapidly, where it is cut and extinguished. However, due to the above arrangement, the arc is generated inside the flared opening and requires airflow to propel it across it. Utility Model Content

[0004] The present invention aims to provide a contact arc extinguishing system for a switch, which helps the arc to quickly cross the flared end by extending the arc-initiating head of the long contact piece through the flared end, facilitating the rapid entry of the arc into the grid of the arc extinguishing chamber, and effectively preventing the arc from retreating.

[0005] The present invention accomplishes its objective as follows: a contact arc-extinguishing system for a switch, comprising an arc-extinguishing chamber and a contact system, wherein the contact system includes a moving contact and a stationary contact, wherein the moving contact, after actuation, makes contact with or separates from the stationary contact, the arc-extinguishing chamber is located on one side of the contact system in the opening direction, the arc-extinguishing chamber includes a pair of side plates, multiple grid plates disposed between the pair of side plates, and a pair of gas-generating elements, wherein the pair of gas-generating elements are respectively located at the lower edge of the grid plates, the pair of gas-generating elements are arranged opposite to each other, and form a flared mouth with a larger lower diameter and a smaller upper diameter in the upward direction, the contact plate of the moving contact includes a long contact plate and a short contact plate, wherein the arc-inducing head of the long contact plate extends through the flared mouth.

[0006] In one specific embodiment of this utility model, the inside of the flared mouth has an inwardly protruding gas-generating part.

[0007] In another specific embodiment of this utility model, the long contact piece is provided with a main contact and an arc contact. The arc contact is located on the side of the main contact near the grid piece, and the arc contact on the long contact piece also extends beyond the flared opening and is located above the flared opening.

[0008] In another specific embodiment of this utility model, the long contact piece is provided with a main contact and an arc contact, the arc contact is located on the side of the main contact near the grid piece, and the arc contact on the long contact piece is located in the flared opening.

[0009] In another specific embodiment of this utility model, the short contact piece is also provided with a main contact and an arc contact, and the arc contact of the short contact piece is located below the flared opening.

[0010] In another specific embodiment of this utility model, the main contacts on the long contact piece and the main contacts on the short contact piece are aligned.

[0011] In a further specific embodiment of this utility model, the gas generating component includes an extension portion, a pair of extension portions extending toward the contact piece, the space between them forming a front cavity, the extension portion extending through the head of the short contact piece, the head of the short contact piece being located within the front cavity.

[0012] In a more specific embodiment of this utility model, the arc contact point on the short contact piece is located within the front cavity.

[0013] In yet another specific embodiment of this utility model, a narrow slit is formed above the flared mouth, and the portion of the long contact piece extending through the arc-drawing head of the flared mouth is located within the narrow slit.

[0014] In yet another specific embodiment of this utility model, the flared opening is located on the side close to the stationary contact.

[0015] Due to the above-mentioned structure, this utility model has the following beneficial effects: by extending the arc-initiating head of the long contact piece through the flared opening, it helps the arc to quickly cross the flared opening, which facilitates the arc to quickly enter the grid plate of the arc-extinguishing chamber and effectively prevents the arc from retreating. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the switch in this utility model;

[0017] Figure 2 This is a three-dimensional schematic diagram of the moving contact and the arc-extinguishing chamber in this utility model;

[0018] Figure 3 This is a schematic diagram of one side of the moving contact and the arc-extinguishing chamber in the first embodiment of this utility model;

[0019] Figure 4 This is a schematic diagram showing the cooperation between the moving contact and the inside of the arc-extinguishing chamber in the first embodiment of this utility model;

[0020] In the figure: 1. Arc extinguishing chamber, 11. Side plate, 12. Grid plate; 13. Moving arc ignition plate, 14. Gas generating component, 141. Extension, 15. Arc extinguishing cover, 16. Anti-freezing bracket; 2. Moving contact, 21. Contact piece, 211. Long contact piece, 2111. Arc ignition head, 212. Short contact piece, 213. Main contact, 214. Arc contact, 22. Contact support, 23. Outlet bar; 3. Housing, 31. Base, 32. Base plate. Detailed Implementation

[0021] The specific embodiments of this utility model are described in detail below with reference to the accompanying drawings. However, the description of the embodiments is not a limitation on the technical solution. Any formal but not substantive changes made based on the concept of this utility model should be considered within the protection scope of this utility model.

[0022] In the following description, all directional (or orientational) concepts involving up, down, left, right, front, and back refer to the position of the figure being described, and are intended to facilitate public understanding. Therefore, they should not be construed as a special limitation on the technical solution provided by this utility model.

[0023] like Figure 1 , Figure 2 The switch includes a disconnector and a circuit breaker. The switch comprises an arc-extinguishing chamber 1, a contact system, and a housing 3. The housing 3 includes a base 31 and a bottom plate 32, which are joined together to form the housing 3. Typically, the base 31 and the bottom plate 32 are secured using threaded fastening.

[0024] The contact system includes a moving contact 2 and a stationary contact (not shown). The moving contact 2 is mounted on the base 31, while the stationary contact is mounted on the base plate 32. Specifically, the moving contact 2 is rotatably mounted, while the stationary contact is fixedly mounted. After the moving contact 2 actuates, it makes contact with or separates from the stationary contact. The arc-extinguishing chamber 1 is located on one side of the contact system in the opening direction.

[0025] like Figure 2The arc-extinguishing chamber 1 includes a pair of side plates 11 and multiple grid plates 12 disposed between the pair of side plates 11. The multiple grid plates 12 are spaced apart from each other. The arc-extinguishing chamber 1 also includes a moving arc-initiating plate 13, a deionization component, and an arc-extinguishing cover 15. One end of the moving arc-initiating plate 13 is placed outside the array of grid plates 12 and spaced apart from a nearby grid plate 12. The other end is bent and extends into the interior of the arc-extinguishing chamber 1, forming the extension end of the moving arc-initiating plate 13. The moving arc-initiating plate 13 is located on the side corresponding to the moving contact 2. The deionization component is used to deionize the gas at the outlet side of the grid plate 12. Typically, the deionization component should include a perforated plate (not shown). The perforated plate is located at the outlet side of the grid plate 12 and is adjacent to the grid plate 12.

[0026] The deionization component includes a deionization bracket 16, which is a frame in shape, and the filter unit of the deionization component is installed inside it. A pair of side plates 11 are fixed to both sides of the deionization bracket 16.

[0027] The arc-extinguishing cover 15 is located at the top of the arc-extinguishing chamber 1, and has an exhaust hole thereon. The gas inside the arc-extinguishing chamber 1 is discharged to the outside of the arc-extinguishing chamber 1 through the exhaust hole on the arc-extinguishing cover 15.

[0028] like Figure 3 , Figure 4 The moving contact 2 includes a contact piece 21, a contact support 22, and a lead-out bar 23. Multiple contact pieces 21 are mounted on the contact support 22. Typically, the two are hinged together by a pivot, allowing the contact pieces 21 to swing with the contact support 22 while maintaining a certain angle of rotational engagement. The lead-out bar 23 is fixed inside the housing 3, with one end extending outside the housing 3. A conductive flexible connection (not shown) is provided between the lead-out bar 23 and the contact piece 21 to achieve electrical connection. This conductive flexible connection ensures that the contact piece 21 is electrically connected to the lead-out bar 23 without affecting the swinging of the contact piece 21.

[0029] The contact pieces 21 are multiple and arranged side by side. Each contact piece 21 includes long contact pieces 211 and short contact pieces 212. Preferably, the long contact pieces 211 are located in the center of the contact piece array, while the short contact pieces 212 are located on either side of the long contact pieces 211. Specifically, in this embodiment, there are two long contact pieces 211, adjacent to each other, forming one group, while the short contact pieces 212 are divided into two groups, with each group of short contact pieces 212 located on either side of a group of long contact pieces 211. More specifically, in this embodiment, five short contact pieces 212 form one group, that is, ten short contact pieces 212 form two groups. Of course, the long contact pieces 211 can also be four, forming one group and centered; while the short contact pieces 212 can be four, forming one group.

[0030] like Figure 3 Both the long contact piece 211 and the short contact piece 212 are provided with a main contact 213 and an arc contact 214. The arc contact 214 is located above the main contact 213, that is, the arc contact 214 is located on the side of the main contact 213 closer to the grid piece 12. Therefore, both the long contact piece 211 and the short contact piece 212 are arc contacts.

[0031] The long contact piece 211 has an extended arc-inducing head 2111. The arc-inducing head 2111 refers to the portion of the long contact piece 211 facing the rotating end of the long contact piece 211 at the position where it engages with the stationary contact to initiate an arc. When the long contact piece 211 has an arc contact point 214, this refers to the portion of the long contact piece 211 facing the rotating end of the long contact piece 211. After the long contact piece 211 and the short contact piece 212 are installed, the arc-inducing head 2111 is located on the side of the head of the short contact piece 212 closer to the grid plate 21, meaning the arc-inducing head 2111 is higher than the head of the short contact piece 212. The arc-inducing head 2111 is sickle-shaped and extends and curves towards the back side of the long contact piece 211.

[0032] like Figure 3 , Figure 4The arc-extinguishing chamber 1 further includes a pair of gas-generating elements 14, which are located at the lower edge of the grid plate 12 and respectively wrap around a pair of grid plate legs of the grid plate 12. The pair of gas-generating elements 14 are arranged opposite to each other, forming a flared opening between them. The flared opening is wider at the bottom and narrower at the top, meaning the diameter of the flared opening decreases in the upward direction. Each gas-generating element 14 includes an extension 141, which extends towards the contact plate 21. The space between them forms a front cavity, and the extensions 141 extend past both ends of the side-by-side contact plates 21. This ensures that if an arc is generated on the short contact plate 212, it is also located within the cavity of the flared opening. Specifically, the extensions 141 extend past the head of the short contact plate 212, and the head of the short contact plate 212 is located within the front cavity. Preferably, the arc contact point 214 on the short contact plate 212 is located within the front cavity. The arc contact 214 on the short contact piece 212 is located in the front cavity, meaning that the arc contact 214 on the short contact piece 212 is always located in the front cavity during the process of engaging with the front cavity.

[0033] The arc-initiating head 2111 of the long contact piece 211 extends beyond the flared opening, helping the electric arc to quickly cross the flared opening. Preferably, the arc contact point 214 on the long contact piece 211 also extends beyond the flared opening and is located above the flared opening, so that the electric arc is generated above the flared opening. Since the flared opening has the function of accelerating airflow, it is beneficial for the electric arc to enter the grid plate 12 more quickly. After the airflow is accelerated by the flared opening, it pushes the electric arc to move upward quickly.

[0034] In this embodiment, the arc contact 214 of the short contact piece 212 is located below the flared opening. The main contact 213 of the long contact piece 211 and the main contact 213 on the short contact piece 212 are aligned.

[0035] More preferably, a narrow slit is formed above the flared opening, and the portion of the long contact piece 211 that extends through the arc-drawing head 2111 of the flared opening is located within the narrow slit.

[0036] Preferably, the flared opening is located on one side of the stationary contact. The flared opening refers to the portion that narrows on both sides in the upward direction, excluding a straight portion with a constant width or an enlarged portion whose width increases in the upward direction.

[0037] The above-described configuration allows the flared opening to accelerate airflow, facilitating the rapid entry of the electric arc into the grid plate 12.

[0038] Preferably, the inside of the flared opening has an inwardly protruding gas-generating section, which can preferentially contact the electric arc relative to the flared opening. For example, the gas-generating section is burr-like, boss-like, or has a curved protrusion. This arrangement allows the electric arc to make full contact with the gas-generating section when passing through the flared opening, reducing the arc energy.

Claims

1. A contact arc-extinguishing system for a switch, comprising an arc-extinguishing chamber (1) and a contact system, wherein the contact system comprises a moving contact (2) and a stationary contact, wherein the moving contact (2) contacts or separates from the stationary contact after actuation, the arc-extinguishing chamber (1) is located on one side of the contact system in the opening direction, the arc-extinguishing chamber (1) comprises a pair of side plates (11), a plurality of grid plates (12) disposed between the pair of side plates (11), and a pair of gas-generating elements (14), wherein the pair of gas-generating elements (14) are respectively located at the lower edge of the grid plates (12), characterized in that: The pair of gas generating components (14) are arranged opposite each other and form a flared mouth with a larger diameter at the bottom and a smaller diameter at the top in the upward direction. The contact piece (21) of the moving contact (2) includes a long contact piece (211) and a short contact piece (212). The arc-inducing head (2111) of the long contact piece (211) extends through the flared mouth.

2. The contact arc extinguishing system of a switch according to claim 1, characterized in that: The inside of the flared mouth has an inwardly protruding gas-generating section.

3. The contact arc extinguishing system of a switch according to claim 1, characterized in that: The long contact piece (211) is provided with a main contact (213) and an arc contact (214). The arc contact (214) is located on the side of the main contact (213) closer to the grid piece (12). The arc contact (214) on the long contact piece (211) also extends through the horn and is located above the horn.

4. The contact arc extinguishing system of a switch according to claim 1, characterized in that: The long contact piece (211) is provided with a main contact (213) and an arc contact (214). The arc contact (214) is located on the side of the main contact (213) closer to the grid plate (12), and the arc contact (214) on the long contact piece (211) is located in the horn opening.

5. The contact arc extinguishing system of a switch according to claim 3, characterized in that: The short contact piece (212) is also provided with a main contact (213) and an arc contact (214), and the arc contact (214) of the short contact piece (212) is located below the horn opening.

6. The contact arc extinguishing system of a switch according to claim 5, characterized in that: The main contacts (213) of the long contact piece (211) and the main contacts (213) of the short contact piece (212) are aligned.

7. The contact arc extinguishing system of a switch according to claim 1, characterized in that: The gas generating component (14) includes an extension (141), a pair of extensions (141) extending toward the contact piece (21), the space between them forming a front cavity, the extension (141) protruding through the head of the short contact piece (212), the head of the short contact piece (212) being located in the front cavity.

8. The contact arc extinguishing system of a switch according to claim 7, characterized in that: The arc contact (214) on the short contact piece (212) is located in the front cavity.

9. The contact arc extinguishing system of a switch according to claim 1, characterized in that: A narrow slit is formed above the flared mouth, and the portion of the long contact piece (211) that extends through the arc-drawing head (2111) of the flared mouth is located within the narrow slit.

10. The contact arc extinguishing system of a switch according to claim 1, characterized in that: The flared opening is located on the side close to the stationary contact.

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