Circuit breaker

Abstract

A circuit breaker provided by the present invention comprises a main loop and an arc-extinguishing conductive loop which are arranged in parallel, the main loop is provided with a moving contact and a static contact, the arc-extinguishing conductive loop is provided with a photoresistor, and when the moving contact and the static contact are broken due to a fault current to generate an electric arc, the resistance value of the photoresistor is reduced under the arc light effect of the electric arc. The arc-extinguishing conductive loop is in a conducting state, so that a fault current mainly passes through the arc-extinguishing conductive loop, namely the arc-extinguishing conductive loop plays a role in shunting, and the fault current flowing through the main loop is reduced, so that the arc ablation of the moving contact and the static contact is reduced, the energy of the arc is weakened, and the contact is not easy to have the conditions of fusion welding and ablation; when the moving contact and the static contact are completely disconnected, the electric arc is extinguished, the resistance value of the photoresistor is increased, and the arc-extinguishing conductive loop is in an open-circuit state, so that fault current is effectively cut off, the moving contact and the static contact are protected, and the service life of the circuit breaker is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of low-voltage electrical appliances, and in particular to a circuit breaker. Background Art

[0002] A circuit breaker is a protective device installed in a terminal distribution line, which is mainly used for overload and short circuit protection of lines and electrical equipment.

[0003] The contact assembly of the existing circuit breaker includes a moving contact and a stationary contact, both of which are provided with silver spots. When a fault current such as a short circuit or an overload occurs, the short circuit tripping mechanism and the overload tripping mechanism will drive the contact bracket to rotate toward the opening position, thereby driving the moving contact to separate from the stationary contact. Since the fault current is often much larger than the normal working current, this will cause the contact to generate a large amount of heat, the temperature will rise sharply, and the contact will be welded; in addition, under the action of the fault current, a strong arc will be generated between the contacts, and the arc will burn the silver spot, thereby shortening the service life of the circuit breaker. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that the moving and static contacts are easily welded and ablated due to fault current, resulting in a short service life of the circuit breaker, thereby providing a circuit breaker with a long service life.

[0005] To this end, the present invention provides a circuit breaker, including a main circuit and an arc-extinguishing conductive circuit, the main circuit is provided with a moving contact and a stationary contact; the arc-extinguishing conductive circuit is arranged in parallel with the main circuit, and is provided with a photoresistor, wherein when an arc is generated between the moving contact and the stationary contact, the resistance of the photoresistor decreases under the action of the arc light, and the arc-extinguishing conductive circuit forms a conducting state; after the arc is extinguished, the resistance of the photoresistor increases, and the arc-extinguishing conductive circuit forms a circuit-breaking state.

[0006] The photoresistor is arranged adjacent to the moving contact and the stationary contact.

[0007] An arc-starting piece for guiding the arc to the arc-extinguishing chamber is arranged below the moving contact and the stationary contact, and a photoresistor is arranged above them.

[0008] A circuit board assembly is arranged in the circuit breaker housing. The circuit board assembly includes a circuit board and a photoresistor arranged on the circuit board. Two ends of the circuit board are respectively connected to corresponding conductive parts in the circuit breaker housing through conductive parts.

[0009] The circuit breaker housing has a first terminal and a second terminal respectively arranged on both sides thereof, and the static contact is connected to the first terminal. It includes a first connecting plate, a static contact plate and an arc striking angle which are bent and connected in sequence from top to bottom. Contacts are arranged on the static contact plate, one of which is fixedly connected to the first connecting plate, and the other is fixedly connected to the second terminal.

[0010] The circuit breaker housing has a first wiring terminal and a second wiring terminal which are arranged on two sides thereof, and two conductive members are respectively connected to the first wiring terminal and the second wiring terminal.

[0011] The conductive member is a conductive plate or a conductive wire.

[0012] The moving contact is mounted on a contact bracket, and the contact bracket is rotatably mounted on the circuit breaker housing through a rotating shaft. An avoidance groove for avoiding the rotating shaft is formed on the circuit board.

[0013] The technical solution of the present invention has the following advantages: 1. The circuit breaker provided by the present invention comprises a main circuit and an arc extinguishing conductive circuit arranged in parallel, the main circuit is provided with a moving contact and a stationary contact, the arc extinguishing conductive circuit is provided with a photoresistor, when the moving contact and the stationary contact are disconnected due to a fault current to generate an arc, the resistance of the photoresistor decreases under the action of the arc light, and the arc extinguishing conductive circuit forms a conducting state, so that the fault current mainly passes through the arc extinguishing conductive circuit, that is, the arc extinguishing conductive circuit plays a shunt role, reducing the fault current flowing through the main circuit, thereby reducing the temperature rise of the moving and stationary contacts, and weakening the energy of the arc, and the contacts are not prone to welding and ablation; when the moving contact and the stationary contact are completely disconnected, the arc is extinguished, the resistance of the photoresistor increases, and the arc extinguishing conductive circuit forms a circuit-breaking state, thereby effectively cutting off the fault current, protecting the moving and stationary contacts, and increasing the service life of the circuit breaker.

[0014] 2. In the circuit breaker provided by the present invention, arc-striking members for directing the arc to the arc-extinguishing chamber are arranged below the moving contact and the static contact, and a photoresistor is arranged above the moving contact and the static contact. This makes rational use of the internal space of the circuit breaker housing, and the photoresistor is closer to the moving and static contacts, so the reaction speed is faster.

[0015] 3. In the circuit breaker provided by the present invention, one conductive part of the circuit board is fixedly connected to the first connecting plate of the static contact, and the other conductive part is fixedly connected to the second connecting terminal, so that the connection is quick and convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a structural schematic diagram of the circuit breaker of the present invention; Figure 2 is a stereoscopic view of the circuit board assembly, the static contact and the second terminal; Figure 3 This is the circuit diagram of the circuit breaker.

[0018] Explanation of the reference numerals in the accompanying drawings: 1. Main circuit; 2. Moving contact; 3. Static contact; 4. Arc extinguishing conductive circuit; 5. Photoresistor; 6. Arc extinguishing chamber; 7. Arc striking member; 8. Circuit board assembly; 9. Circuit board; 10. Conductive member; 11. First terminal; 12. Second terminal; 13. First connecting plate; 14. Static contact plate; 15. Arc striking angle; 16. Contact; 17. Avoidance groove. DETAILED DESCRIPTION

[0019] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0023] Example This embodiment provides a circuit breaker, such as Figure 1 and Figure 3 As shown, it includes a circuit breaker housing, a main circuit 1 and an arc-extinguishing conductive circuit 4.

[0024] like Figure 2 As shown, the main circuit 1 is provided with a moving contact 2 and a stationary contact 3. Figure 3 As shown, the static contact 3 includes a first connecting plate 13, a static contact plate 14 and an arc-striking angle 15 which are bent and connected in sequence from top to bottom. The static contact plate 14 is provided with a contact 16. The moving contact 2 is mounted on a contact bracket (not shown in the figure), and the contact bracket is rotatably mounted on the circuit breaker housing through a rotating shaft. An arc-striking member 7 for guiding the arc to the arc-extinguishing chamber 6 is provided below the moving contact 2 and the static contact 3.

[0025] A circuit board assembly 8, a first wiring terminal 11 and a second wiring terminal 12 are arranged in the circuit breaker housing.

[0026] Circuit board assembly 8, such as Figure 1 and Figure 2 As shown, it includes a circuit board 9, and the photoresistor 5 arranged on the circuit board 9, and the photoresistor 5 is arranged adjacent to the moving contact 2 and the static contact 3, so that it is easier to sense the arc light. In this embodiment, the photoresistor 5 is arranged above the moving contact 2 and the static contact 3. The two ends of the circuit board 9 are respectively connected to the conductive parts in the circuit breaker housing through conductive parts 10. It should be noted that the conductive part 10 can be a conductive plate or a wire. The circuit board 9 is formed with an avoidance groove 17 for avoiding the rotating shaft. The resistance value of the photoresistor 5 changes accordingly according to whether there is an arc between the moving and static contacts, so that the arc extinguishing conductive circuit 4 changes the on-off state, and the circuit board 9 assists and controls the arc extinguishing conductive circuit 4.

[0027] like Figure 2 As shown, the first terminal 11 and the second terminal 12 are respectively arranged on the left and right sides of the circuit breaker housing. In this embodiment, one of the conductive members 10 is fixedly connected to the first connecting plate 13, and the other conductive member 10 is fixedly connected to the second terminal 12.

[0028] As a convertible implementation, the two conductive members 10 are connected to the first connecting terminal 11 and the second connecting terminal 12 respectively.

[0029] like Figure 3 As shown, the arc-extinguishing conductive circuit 4 is arranged in parallel with the main circuit 1, and is provided with a key component, a photoresistor 5. When an arc is generated between the moving contact 2 and the static contact 3, the resistance of the photoresistor 5 decreases under the action of the arc light, and the arc-extinguishing conductive circuit 4 forms a conducting state; after the arc is extinguished, the resistance of the photoresistor 5 increases, and the arc-extinguishing conductive circuit 4 forms a disconnecting state.

[0030] The circuit breaker provided by the present invention comprises a main circuit 1 and an arc-extinguishing conductive circuit 4 which are arranged in parallel. The main circuit 1 is provided with a moving contact 2 and a stationary contact 3. The arc-extinguishing conductive circuit 4 is provided with a photoresistor 5. When the moving contact 2 and the stationary contact 3 are disconnected and an arc is generated due to a fault current, the resistance of the photoresistor 5 becomes a bright resistor (micro-ohm level) under the arc light of the arc, and the arc-extinguishing conductive circuit 4 forms a conducting state. In this way, the fault current mainly passes through the arc-extinguishing conductive circuit 4, that is, the arc-extinguishing conductive circuit 4 plays a shunt role, reducing the fault current flowing through the main circuit 1, thereby reducing the arc ablation of the moving and stationary contacts, and weakening the energy of the arc, so that the contacts are not prone to welding and ablation; when the moving contact 2 and the stationary contact 3 are completely disconnected, the arc is extinguished, the resistance of the photoresistor 5 becomes a dark resistor (mega-ohm level), and the arc-extinguishing conductive circuit 4 forms a circuit-breaking state, thereby effectively cutting off the fault current, protecting the moving and stationary contacts, and improving the service life of the circuit breaker.

[0031] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A circuit breaker, characterized in that: include: A main circuit (1) is provided with a moving contact (2) and a stationary contact (3); The arc-extinguishing conductive circuit (4) is arranged in parallel with the main circuit (1), and is provided with a photoresistor (5), wherein when an arc is generated between the moving contact (2) and the stationary contact (3), the resistance of the photoresistor (5) decreases under the action of the arc light, and the arc-extinguishing conductive circuit (4) forms a conducting state; after the arc is extinguished, the resistance of the photoresistor (5) increases, and the arc-extinguishing conductive circuit (4) forms a disconnecting state.

2. The circuit breaker according to claim 1, characterized in that: The photoresistor (5) is arranged adjacent to the moving contact (2) and the stationary contact (3).

3. The circuit breaker according to claim 1 or 2, characterized in that: An arc-starting member (7) for directing an arc to an arc-extinguishing chamber (6) is arranged below the moving contact (2) and the stationary contact (3), and the photoresistor (5) is arranged above.

4. The circuit breaker according to claim 1, characterized in that: A circuit board assembly (8) is arranged in the circuit breaker housing, the circuit board assembly (8) comprising a circuit board (9) and the photoresistor (5) arranged on the circuit board (9), and two ends of the circuit board (9) are respectively connected to corresponding conductive parts in the circuit breaker housing through conductive parts (10).

5. The circuit breaker according to claim 4, characterized in that: The circuit breaker housing has a first wiring terminal (11) and a second wiring terminal (12) arranged on both sides thereof, the stationary contact (3) being connected to the first wiring terminal (11), comprising a first connecting plate (13), a stationary contact plate (14) and an arc striking angle (15) which are bent and connected in sequence from top to bottom, the stationary contact plate (14) being provided with a contact point (16), one of the conductive members (10) being fixedly connected to the first connecting plate (13), and the other of the conductive members (10) being fixedly connected to the second wiring terminal (12).

6. The circuit breaker according to claim 4, characterized in that: The circuit breaker housing has a first wiring terminal (11) and a second wiring terminal (12) respectively arranged on two sides thereof, and the two conductive members (10) are respectively connected to the first wiring terminal (11) and the second wiring terminal (12).

7. The circuit breaker according to any one of claims 4 to 6, characterized in that: The conductive member (10) is a conductive plate or a conductive wire.

8. The circuit breaker according to claim 4, characterized in that: The moving contact (2) is mounted on a contact bracket, and the contact bracket is rotatably mounted on the circuit breaker housing via a rotating shaft. An avoidance groove (17) for avoiding the rotating shaft is formed on the circuit board (9).

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