The present invention relates to an arc-extinguishing device and a circuit breaker provided with the arc-extinguishing device.
At present, a circuit breaker is mainly composed of a contact system, an arc-extinguishing system, a housing, an operation mechanism, and a release system. The contact system is mainly composed of a moving contact, a fixed contact, a moving contact point, a fixed contact point and an arcing horn, and the arc-extinguishing system is mainly composed of an arc-extinguishing grid sheet, a support, a flash barrier, and a gas-evolving hood. Because the existing circuit breaker does not take into account the cooperation between the arc-extinguishing system and the contact system during an arc extinguishing process, strong energy of a short circuit current will easily burn out the circuit breaker in case of occurrence of short-circuiting. In this way, the arc-extinguishing system and the contact system are required to cooperatively work to form an arc-extinguishing device with good performance so as to help the circuit breaker to successfully disconnect the short circuit current.
In order to solve the problems existing in the prior art, the present invention provides an arc-extinguishing device and a circuit breaker provided with the arc-extinguishing device. In this case, the circuit breaker can more easily extinguish an electric arc.
On one hand, the present invention provides an arc-extinguishing device, including an arc-extinguishing chamber, where the arc-extinguishing chamber comprises a support, a plurality of arc-extinguishing grid sheets, a first gas-evolving hood, and a second gas-evolving hood; the plurality of arc-extinguishing grid sheets are mounted on the supports, the arc-extinguishing grid sheet has a groove to form a moving track for a moving contact, both sides of the groove extend toward the moving contact respectively to form a first extension leg and a second extension leg, an end and an inner side of the first extension leg are wrapped by the first gas-evolving hood, and an end and an inner side of the second extension leg are wrapped by the second gas-evolving hood; a surface of the gas-evolving hood extending along the inner side of the extension leg toward the groove is referred to as a wrapping surface, a front edge of the wrapping surface is aligned with or goes beyond a front end of the moving contact.
In an example of the present invention, the front edge of the wrapping surface is aligned with or even goes beyond the front end of the moving contact, so that a gas-evolving function is enabled. In this way, in a case of short-circuiting, electric arcs can be gathered to increase an arc voltage, thereby helping the circuit breaker to disconnect a short circuit current.
Preferably, a shape of the front edge of the wrapping surface is consistent with a moving trajectory of the front end of the moving contact, that is, the front edge of the wrapping surface keeps a basically same distance from the moving trajectory of the front end of the moving contact.
Furthermore, the front edge of the wrapping surface has a protrusion facing toward the inside of the groove of the arc-extinguishing grid sheet to form a necking structure for the moving contact, so as to better gather the electric arcs; a shape of the protrusion is consistent with the moving trajectory of the front end of the moving contact, that is, the protrusion keeps a basically same distance from the moving trajectory of the front end of the moving contact.
Furthermore, the arc-extinguishing device further includes the moving contact which is of rod shape, rotatable around a shaft and provided with a moving contact point, and the front end of the moving contact is movable along a track formed by the grooves of the plurality of arc-extinguishing grid sheets. Preferably, an insulation plate is connected at a position that is on the moving contact and behind the moving contact point, and the insulation plate is driven by the moving contact to move. In this case, an opening of a rear region of the arc-extinguishing device is reduced, so that the electric arc will more easily enter a front end of the arc-extinguishing device, i.e., an end of the arc-extinguishing grid sheet having no groove, rather than enter the end of the arc-extinguishing grid sheet having extension legs.
Furthermore, the arc-extinguishing device further includes a fixed contact, where the fixed contact is of U-shaped structure on which a fixed contact point is disposed.
Furthermore, the fixed contact further includes a magnetic conducting block disposed in the U-shaped structure. The magnetic conducting block can increase a magnetic field strength near the fixed contact to generate a larger magnetic blow force so as to blow the electric arc into the arc-extinguishing grid sheets of the arc-extinguishing chamber.
Further, the fixed contact further includes an insulation cover, where the insulation cover wraps the U-shaped structure to insulate the non-opening end of the U-shaped structure from the arc-extinguishing chamber because this region is easily broken down by electric arc. Preferably, the insulation cover is like a cap. In a preferred example of the present invention, a gap for exposing the fixed contact point may be disposed on the insulation cover.
On the other hand, the present invention provides a circuit breaker provided with the above arc-extinguishing device.
Specifically, the present invention provides a circuit breaker, including a housing, a moving contact, a fixed contact, and an arc-extinguishing device. The arc-extinguishing device includes an arc-extinguishing chamber, the arc-extinguishing chamber includes a support, a plurality of arc-extinguishing grid sheets, a first gas-evolving hood, and a second gas-evolving hood; the plurality of arc-extinguishing grid sheets are mounted on the supports, the arc-extinguishing grid sheet has a groove to form a moving track for a moving contact, both sides of the groove extend toward the moving contact respectively to form a first extension leg and a second extension leg, an end and an inner side of the first extension leg are wrapped by the first gas-evolving hood, and an end and an inner side of the second extension leg are wrapped by the second gas-evolving hood; a surface of the gas-evolving hood extending along the inner side of the extension leg toward the groove is referred to as a wrapping surface, a front edge of the wrapping surface is aligned with or goes beyond a front end of the moving contact.
Preferably, a shape of the front edge of the wrapping surface is consistent with a moving trajectory of the front end of the moving contact, that is, the front edge of the wrapping surface keeps a basically same distance from the moving trajectory of the front end of the moving contact.
Furthermore, the front edge of the wrapping surface has a protrusion facing toward the inside of the groove of the arc-extinguishing grid sheet to form a necking structure for the moving contact, so as to better gather the electric arcs; a shape of the protrusion is consistent with the moving trajectory of the front end of the moving contact, that is, the protrusion keeps a basically same distance from the moving trajectory of the front end of the moving contact.
The moving contact is of rod shape, rotatable around a shaft and provided with a moving contact point, and the front end of the moving contact is movable along a track formed by the grooves of the plurality of arc-extinguishing grid sheets. Preferably, an insulation plate is connected at a position that is on the moving contact and behind the moving contact point, and the insulation plate is driven by the moving contact to move. In this case, an opening of a rear region of the arc-extinguishing device is reduced, so that the electric arc will more easily enter the front end of the arc-extinguishing device, i.e., an end of the arc-extinguishing grid sheet having no groove, rather than enter the end of the arc-extinguishing grid sheet having extension legs.
The fixed contact is of U-shaped structure on which a fixed contact point is disposed.
Furthermore, the fixed contact further includes a magnetic conducting block which is disposed in the U-shaped structure. The magnetic conducting block can increase a magnetic field strength near the fixed contact to generate a larger magnetic blow force so as to blow the electric arc into the arc-extinguishing grid sheets of the arc-extinguishing chamber.
Furthermore, the fixed contact further includes an insulation cover wrapping the U-shaped structure to insulate the non-opening end of the U-shaped structure from the arc-extinguishing chamber because this region is easily broken down by electric arc. Preferably, the insulation cover is like a cap. In a preferred example of the present invention, a gap for exposing the fixed contact point is disposed on the insulation cover.
The term “front” used herein refers to a direction in which the moving contact points to the arc-extinguishing sheet, and the term “rear” used herein refers to a reverse direction.
The arc-extinguishing device and the circuit breaker provided with the arc-extinguishing device provided by the present invention have excellent arc-extinguishing performance, so that the electric arcs will be moved toward the arc-extinguishing grid sheets under the joint action of the magnetic blow force and the gas blow force and gathered by narrow channels defined by the gas-evolving hoods. In this way, the arc voltage will be increased to extinguish the electric arcs more effectively, thereby helping the circuit breaker to disconnect the short circuit current.
Numerals of drawings are described as follows: 1. circuit breaker, 2. arc-extinguishing chamber, 21. arc-extinguishing grid sheet, 211. grid sheet rear end (211a. first extension leg, 211b. second extension leg), 212. grid sheet front end, 22. support (22a. left support, 22b. right support), 3. gas-evolving hood (3a. first gas-evolving hood, 3b. second gas-evolving hood), 31. wrapping surface (31a. first wrapping surface, 31b. second wrapping surface); 32. protrusion (32a. first protrusion, 32b. second protrusion), 4. housing, 5. moving contact, 51. moving contact front end, 52. moving contact point, 6. fixed contact, 61. U-shaped structure, 62. fixed contact point, 7. insulation cover, 8. magnetic conducting block, 9. insulation plate.
In order to fully understand the object, features and effects of the present invention, the concept, specific structure, and technical effects of the present invention will be further described in combination with the accompanying drawings.
It is understood that in the descriptions of the present invention, orientation or positional relationship indicated by the terms “upper”, “lower”, “front”, “rear”, “left”, “right”, “top”, “bottom”, “inner”, “outer”, “vertical” and “horizontal” and the like is based on orientation or positional relationship shown in the accompanying drawings, and is used only for ease of descriptions and simplification rather than for indicating or implying that the indicated device or element must have a particular orientation, or be constructed and operated in a specific orientation and thus shall not be interpreted as limiting of the present invention.
Further, the terms “first” and “second” are used only for descriptions rather than understood as indicating or implying relative importance or implicitly indicating a number of the indicated technical features. Therefore, the features defined by “first” and “second” may explicitly or implicitly include one or more of the features.
In the present invention, unless otherwise indicated, the terms “mount”, “connect”, “couple”, “fix” and the like shall be understood in a broad sense, which may include for example, fixed connection, detachable connection, or one-piece connection; mechanical connection, or electrical connection; direct connection or connection through an intermediate medium, and internal communication of two elements. Those skilled in the art may understand the specific meaning of the above terms according to the actual situations.
As shown in
As shown in
The circuit breaker or the arc-extinguishing device further includes a moving contact 5. As shown in
As shown in
As shown in
The above descriptions are made to the preferred examples of the present invention. It should be understood that those skilled in the art may make various modifications and changes according to the idea of the present invention without paying creative work. Therefore, all technical solutions obtained by those skilled in the art by performing logical analysis, inference and limited tests based on the idea of the present invention and the prior art shall fall within the scope of protection defined by the claims.
Number | Date | Country | Kind |
---|---|---|---|
201811347327.0 | Nov 2018 | CN | national |
This application is a national stage application of PCT/CN2019/077966. This application claims priorities from PCT Application No. PCT/CN2019/077966, filed Mar. 13, 2019, and from the Chinese patent application 201811347327.0 filed Nov. 13, 2018, the content of which is incorporated herein in the entirety by reference.
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/CN2019/077966 | 3/13/2019 | WO | 00 |