CN-122029632-A - Circuit breaker for wiring

Abstract

The present invention relates to a circuit breaker for wiring, and more particularly, to a circuit breaker for wiring in which insulation performance of a base assembly is improved. According to the circuit breaker for wiring of the embodiments of the present invention, the leakage preventing portion is formed to protrude downward along the contact surface of the bottom surface of the two molded articles constituting the base housing, and the leakage preventing coupling portion is formed as a groove at the bottom of the housing for insertion coupling of the leakage preventing portion, so that the leakage preventing portion is engaged with the leakage preventing coupling portion, thereby preventing the base housing from being opened.

Inventors

• WU JINGHUAN
• WU JIHUAN
• LI GUANGYUAN

Assignees

• LS电气株式会社

Dates

Publication Date

20260512

Application Date

20240718

Priority Date

20231221

Claims (15)

1. 1. A circuit breaker for wiring, comprising: casing of circuit breaker for wiring, and A base housing provided inside the housing and accommodating the contact portion and the arc extinguishing portion; A leakage-proof part is formed on the bottom surface of the base shell in a protruding way, A leakage-proof joint part is formed at the bottom of the shell as a groove for the leakage-proof part to insert and joint.
2. 2. The circuit breaker for wiring according to claim 1, wherein, The leakage preventing part is formed on the bottom surface of the base shell along the length direction.
3. 3. The circuit breaker for wiring according to claim 1, wherein, The base housing is composed of a base housing first body accommodating the contact portion and the arc extinguishing portion, and a base housing second body coupled to the base housing first body.
4. 4. The circuit breaker for wiring according to claim 3, wherein, The leakage preventing portion is formed at a portion where the base housing first body and the base housing second body meet each other.
5. 5. The circuit breaker for wiring according to claim 4, wherein, The leakage preventing part is composed of a leakage preventing part first main body formed on the base housing first main body and a leakage preventing part second main body formed on the base housing second main body.
6. 6. The circuit breaker for wiring according to claim 5, wherein, The leakage-proof part first main body is formed on the side surface connected with the base shell second main body, The leakage preventing part second body is formed on the side surface connected with the first body of the base shell.
7. 7. The circuit breaker for wiring according to claim 1, wherein, The leakage-proof joint portions are formed along the central axes of the respective phases at the bottom of the housing.
8. 8. The circuit breaker for wiring according to claim 1, wherein, The leak-proof joint is formed across between the power source side exhaust pipe and the load side exhaust pipe of the housing.
9. 9. The circuit breaker for wiring according to claim 1, wherein, A rib is formed between the leakage-proof coupling portion and the exhaust pipe of the terminal portion to enhance strength.
10. 10. The circuit breaker for wiring according to claim 1, wherein, The leakage preventing part has a cut-out part with a part cut-out at the middle part.
11. 11. The circuit breaker for wiring according to claim 1, wherein, The leakage-proof joint portion is provided with a cut portion, a portion of which is formed parallel to the bottom portion, at an intermediate portion.
12. 12. The circuit breaker for wiring according to claim 3, wherein, A side leakage preventing part is formed on the side surface of the base shell in a protruding mode.
13. 13. The circuit breaker for wiring according to claim 12, wherein, The housing is formed with a side leakage-proof coupling portion to which the side leakage-proof portion is coupled.
14. 14. The circuit breaker for wiring according to claim 13, wherein, The side leakage preventing part is composed of a side leakage preventing part first body formed on the base housing first body and a side leakage preventing part second body formed on the base housing second body.
15. 15. The circuit breaker for wiring according to claim 5, wherein, A groove part with a part cut is arranged on the contact surface of one of the leakage-proof part first main body and the leakage-proof part second main body, A part of the protrusion protruding toward one of the leakage preventing part first body and the leakage preventing part second body and being inserted and combined with the groove part is arranged on the contact surface of the other one of the leakage preventing part first body and the leakage preventing part second body.

Description

Circuit breaker for wiring Technical Field The present invention relates to a circuit breaker for wiring, and more particularly, to a circuit breaker for wiring in which insulation performance of a base assembly is improved. Background In general, a circuit breaker for wiring (MCCB: molded Case Circuit Breaker, molded case circuit breaker) is an electrical device that automatically opens a circuit to protect a circuit and a load when an electrical overload state or a short-circuit fault occurs. The circuit breaker for wiring may be generally composed of a terminal portion that can be connected to a power source side or a load side, a contact portion that includes a fixed contact and a movable contact that contacts or separates from the fixed contact to connect or separate a circuit, an opening/closing mechanism that provides power necessary for opening/closing the circuit by moving the movable contact, a trip portion that detects an overcurrent or a short-circuit current flowing through the circuit to guide a trip (trip) operation of the opening/closing mechanism, an Arc extinguishing portion that extinguishes an Arc (Arc) generated when an abnormal current is broken, and the like. Fig. 1 shows a prior art circuit breaker for wiring. Fig. 2 shows an internal structure of a prior art circuit breaker for wiring cut in a longitudinal direction. The conventional circuit breaker 10 for wiring includes a fixed contact 21 and a movable contact 22, a contact portion provided for connecting or disconnecting a circuit transmitted from a power supply side to a load side, a switching mechanism portion 40 for supplying power capable of rotating the movable contact 22, an arc extinguishing portion 30 provided for extinguishing an arc generated when a fault current is cut off, and a trip portion 50 for detecting an abnormal current and tripping the switching mechanism, inside a case (case) 11 and a cover (cover) 12 which are a case (enclosure) formed of an insulator. Terminal portions 15 for connecting the circuit to a power source or a load are provided at both end portions of the cases 11 and 12. On the other hand, the contact portions 21 and 22 and the arc extinguishing portion 30 are separately built in the base assembly 20 disposed inside the housing 11. When a fault current flows through the circuit, the trip unit 50 detects the fault current and performs a trip operation of the opening and closing mechanism 40 to separate the movable contact 22 from the fixed contact 21 and cut off the flow of the current, and at this time, arcs a are generated in the contact portions 21 and 22. At this time, the magnitude (intensity) of the arc is proportional to the magnitude of the current. The arc is a phenomenon that gas in the atmosphere instantaneously reaches a plasma state under the action of voltage, and the center temperature of the arc reaches 8,000-12,000 ℃ and has explosive expansion pressure. Therefore, the contact portions 21 and 22 are melted, consumed, and deteriorated, and peripheral components are destroyed, and thus the duration of the arc is greatly affected on the performance and durability of the circuit breaker. Therefore, the arc needs to be rapidly interrupted, extinguished, and discharged in the arc extinguishing portion 30. As described above, in the circuit breaker for wiring, the operation of handling the arc when the fault current is generated becomes a main object of cutting off the fault current and protecting the product, load and line, and directly affects the performance of the circuit breaker. The base assembly 20 operates as follows when the fault current is shut off. Figure 3 shows a base assembly 20. If a fault current occurs, the opening/closing mechanism 40 is operated by the trip unit 50, and the shaft 26 is rotated clockwise with respect to the shaft 25. At this time, an arc is generated in the contact portions 21 and 22, and the arc moves to the grid 31 in the arc extinguishing portion (arc chamber) 30, and is divided and cooled to be extinguished. As the arc moves along the grid 31, the arc voltage rises and eventually the arc will be extinguished. In a circuit breaker for wiring, whether or not the disconnection is successful depends on rapid arc extinction. That is, the rotation speed of the shaft body 26 needs to be fast, and the generated arc needs to be rapidly diffused toward the grid 31 to raise the arc voltage. The arc a generated in the contact portions 21 and 22 by the generation of the fault current is discharged from between the gate plates 31 of the arc extinguishing portion 30 and is discharged through the exhaust port 29 of the base housing 28. After that, the exhaust pipe 19 passing through the lower portion of the terminal portion 15 is released to the outside. Fig. 4 shows a perspective view of a housing 11 and a base assembly 20 of a prior art circuit breaker for wiring. A state is shown as viewed obliquely from above toward the power supply side. In the housing 11,