Double-breakpoint miniature circuit breaker

Abstract

The utility model relates to a miniature circuit breaker with double breakpoints, which comprises a shell, an operating mechanism, a contact system and an electromagnetic release, the operating mechanism comprises a handle, a U-shaped connecting rod, a contact frame, a lock catch and a torsion spring, the contact frame is provided with a sliding hole matched with the U-shaped connecting rod, one end of the U-shaped connecting rod is provided with a driving rod inserted in the sliding hole, and the other end of the U-shaped connecting rod is provided with a spring. A positioning groove matched with the driving rod is formed in the sliding hole, a lock catch groove allowing the driving rod to penetrate through is formed in the lock catch, and a clamping cavity used for clamping the driving rod is formed between the positioning groove and the lock catch groove. The contact system comprises two moving contacts which are symmetrically arranged on two sides of the contact frame, two contact springs which are arranged between the two moving contacts and the contact frame, and static contacts which are matched with the two moving contacts, an insulating support plate is arranged in the shell, and the two static contacts are respectively arranged on two sides of the insulating support plate. The arc extinguishing device has the advantages of simple structure, stable and reliable performance, good arc extinguishing effect and convenience in assembly.

Description

Technical Field

[0001] The utility model relates to a small circuit breaker, in particular to a double-breakpoint small circuit breaker. Background Art

[0002] With the rapid development of the power industry, miniature circuit breakers (MCBs) are widely used as protective devices in electrical circuits in everyday household appliances and various public places. They not only interrupt and connect normal load currents, but also automatically disconnect the circuit when faults such as overloads and short circuits occur, protecting people and property. Existing dual-break miniature circuit breakers include a housing, an operating mechanism disposed within the housing, a contact system, an arc extinguishing chamber, and an electromagnetic release. The operating mechanism of existing MCBs includes a handle, a connecting rod, a trip latch, a lock, and a contact bracket. The operating mechanism is complex in design, has a large number of components, and is cumbersome to assemble. Furthermore, these MCBs suffer from unreliable performance and poor arc extinguishing effectiveness. Summary of the Invention

[0003] The purpose of the utility model is to overcome the defects of the prior art and provide a double-breakpoint miniature circuit breaker with a simple structure, stable and reliable performance, good arc extinguishing effect, and convenient assembly.

[0004] To achieve the above-mentioned objectives, the utility model adopts a double-breakpoint miniature circuit breaker, including a shell, an operating mechanism, a contact system, and an electromagnetic release. The operating mechanism includes a handle rotatably arranged on the shell, a U-shaped connecting rod linked with the handle, a contact frame rotatably arranged in the shell, a lock rotatably arranged on the contact frame, and a torsion spring arranged between the lock and the contact frame. The contact frame is provided with a sliding hole that cooperates with the U-shaped connecting rod, one end of the U-shaped connecting rod has a driving rod inserted into the sliding hole, a positioning groove that cooperates with the driving rod is provided in the sliding hole, and a lock groove for the driving rod to pass through is provided on the lock, and a clamping cavity for clamping the driving rod is formed between the positioning groove and the lock groove. The contact system includes two moving contacts symmetrically arranged on both sides of the contact frame, two contact springs arranged between the two moving contacts and the contact frame, and a static contact cooperating with the two moving contacts. An insulating support plate is provided in the shell, and the two static contacts are respectively provided on both sides of the insulating support plate.

[0005] The beneficial effects of the above structure are: the operating mechanism of the miniature circuit breaker has a simpler structural design and fewer parts. The U-shaped connecting rod cooperates with the lock and contact frame. The driving rod of the U-shaped connecting rod can move within the positioning groove of the sliding hole, thereby realizing the opening and closing operation of the operating mechanism. The lock groove of the lock can lock the driving rod within the positioning groove. The electromagnetic release drives the lock to operate, and the driving rod loses the restriction of the lock, thereby realizing the tripping and opening operation of the small operating mechanism. In addition, the two static contacts are respectively arranged on both sides of the insulating support plate, which has better insulation performance and higher safety. Therefore, the dual-breakpoint miniature circuit breaker has the advantages of simple structure, stable and reliable performance, good arc extinguishing effect, and convenient assembly.

[0006] Specifically, the insulating support plate is provided with two arc extinguishing chambers on one side corresponding to the two stationary contacts. One end of each stationary contact has an arc striking angle extending toward the arc extinguishing chamber. An arc striking plate connected to the arc striking angle is provided at one end of the arc extinguishing chamber. An arc striking plate is provided at the other end of the arc extinguishing chamber, with one end of the arc striking plate extending toward the moving contact. The arc striking angle can quickly guide the arc at the stationary contact into the arc extinguishing chamber along the arc striking plate, while the arc striking plate quickly guides the arc at the moving contact into the arc extinguishing chamber, thereby improving the arc extinguishing performance of the miniature circuit breaker.

[0007] In particular, an arc striking ridge is provided on the side of the arc striking plate facing the moving contact, and the arc striking ridge automatically extends toward the arc extinguishing chamber. The arc striking ridge can quickly introduce the arc into the arc extinguishing chamber, thereby improving the arc extinguishing performance of the miniature circuit breaker.

[0008] In particular, two arc-isolating plates are provided within the housing, corresponding to either side of the arc-striking plate. These plates are provided with iron sheets, and an arc-extinguishing channel is formed between the two arc-isolating plates, connecting the movable contact and the arc-extinguishing chamber. The arc can quickly enter the arc-extinguishing chamber along the arc-extinguishing channel, and the iron sheet can quickly ignite the arc within the arc-extinguishing chamber, thereby improving the arc-extinguishing performance of the miniature circuit breaker.

[0009] In particular, the two arc-isolating plates are each provided with a groove that mates with the iron sheet. The iron sheet has snap-fit ​​tabs at both ends that engage within the grooves, thereby forming a snap-fit ​​connection between the two arc-isolating plates and the iron sheet. This snap-fit ​​connection between the iron sheet and the arc-isolating plates facilitates assembly of the two arc-isolating plates and the iron sheet, making assembly more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is an exploded view of an embodiment of the present utility model.

[0011] Figure 2 This is a diagram of the internal structure of an embodiment of the present utility model. DETAILED DESCRIPTION

[0012] like Figure 1、 2 As shown, the embodiment of the utility model is a double-breakpoint miniature circuit breaker, including a housing 10, an operating mechanism 20, a contact system 30, and an electromagnetic release 11. The operating mechanism 20 includes a handle 21 rotatably set on the housing 10, a U-shaped connecting rod 22 linked with the handle 21, a contact frame 23 rotatably set in the housing 10, a lock 24 rotatably set on the contact frame 23, and a torsion spring 25 set between the lock 24 and the contact frame 23. The contact frame 23 is provided with a sliding hole 231 that cooperates with the U-shaped connecting rod 22. One end of the U-shaped connecting rod 22 has a driving rod 221 inserted into the sliding hole 231. A positioning groove 232 that cooperates with the drive rod 221 is provided in the sliding hole 231, and a locking groove 241 for the drive rod 221 to pass through is provided on the lock 24. A clamping cavity 200 for clamping the drive rod 221 is formed between the positioning groove 232 and the locking groove 241. The contact system 30 includes two moving contacts 31 symmetrically arranged on both sides of the contact frame 23, two contact springs 32 arranged between the two moving contacts 31 and the contact frame 23, and a static contact 33 that cooperates with the two moving contacts 31. An insulating support plate 12 is provided in the shell 10, and the two static contacts 33 are respectively provided on both sides of the insulating support plate 12.

[0013] like Figure 1As shown, the insulating support plate 12 is provided with two arc-extinguishing chambers 34 on one side of each of the two stationary contacts 33. One end of each stationary contact 33 has an arc-strike angle 331 extending toward the arc-extinguishing chamber 34. An arc-strike plate 341 connected to the arc-strike angle 331 is provided at one end of the arc-extinguishing chamber 34. An arc-strike plate 35 is provided at the other end of the arc-extinguishing chamber 34, one end of which extends toward the moving contact 31. The arc-strike angle quickly guides the arc at the stationary contact into the arc-extinguishing chamber along the arc-strike plate, while the arc-strike plate quickly guides the arc at the moving contact into the arc-extinguishing chamber, thereby improving the arc-extinguishing performance of the miniature circuit breaker. An arc-strike protrusion 351 is provided on the side of the arc-strike plate 35 facing the moving contact 31. The arc-strike protrusion 351 automatically guides the contact 31 toward the arc-extinguishing chamber 34. This arc-strike protrusion quickly guides the arc into the arc-extinguishing chamber, thereby improving the arc-extinguishing performance of the miniature circuit breaker. Two arc-isolating plates 36 are provided on both sides of the arc-striking plate 35 in the housing 10. Iron sheets 37 are provided on the two arc-isolating plates 36. An arc-extinguishing channel 300 is formed between the two arc-isolating plates 36, connecting the moving contact 31 and the arc-extinguishing chamber 34. The arc can quickly enter the arc-extinguishing chamber along the arc-extinguishing channel, and the iron sheets can quickly ignite the arc into the arc-extinguishing chamber, thereby improving the arc-extinguishing performance of the small circuit breaker. The two arc-isolating plates 36 are respectively provided with grooves 361 that cooperate with the iron sheets 37. The two ends of the iron sheets 37 have snap-fitting pieces 371 that engage in the grooves 361, forming a snap-fitting connection between the two arc-isolating plates 36 and the iron sheets 37. The iron sheets and the arc-isolating plates are connected by snap-fitting, which facilitates the assembly of the two arc-isolating plates and the iron sheets, making assembly more convenient.

[0014] The operating mechanism of this miniature circuit breaker features a simpler structural design and fewer parts. The U-shaped connecting rod cooperates with the lock and contact frame. The driving rod of the U-shaped connecting rod can move within the positioning groove of the sliding hole, thereby realizing the opening and closing operations of the operating mechanism. The lock groove of the lock can lock the driving rod within the positioning groove. The electromagnetic release drives the lock to operate, and the driving rod loses the restraint of the lock, thereby realizing the tripping and opening operations of the small operating mechanism. The two static contacts are respectively arranged on both sides of the insulating support plate, which has better insulation performance and higher safety. Therefore, this dual-breakpoint miniature circuit breaker has the advantages of simple structure, stable and reliable performance, good arc extinguishing effect, and convenient assembly.

Claims

1. A double-breakpoint miniature circuit breaker, comprising a housing, an operating mechanism, a contact system, and an electromagnetic release, characterized in that: The operating mechanism includes a handle rotatably arranged on the shell, a U-shaped connecting rod that cooperates with the handle, a contact frame rotatably arranged in the shell, a lock buckle rotatably arranged on the contact frame, and a torsion spring arranged between the lock buckle and the contact frame. The contact frame is provided with a sliding hole that cooperates with the U-shaped connecting rod, one end of the U-shaped connecting rod has a driving rod inserted in the sliding hole, a positioning groove that cooperates with the driving rod is provided in the sliding hole, and a lock buckle is provided on the lock buckle for the driving rod to pass through, and a clamping cavity for clamping the driving rod is formed between the positioning groove and the lock buckle. The contact system includes two moving contacts symmetrically arranged on both sides of the contact frame, two contact springs arranged between the two moving contacts and the contact frame, and a static contact that cooperates with the two moving contacts. An insulating support plate is provided in the shell, and the two static contacts are respectively provided on both sides of the insulating support plate.

2. The double-breakpoint miniature circuit breaker according to claim 1, characterized in that: Two arc extinguishing chambers are respectively provided on one side of the insulating support plate corresponding to the two static contacts. One end of the static contact has an arc striking angle extending toward the arc extinguishing chamber. One end of the arc extinguishing chamber is provided with an arc striking piece connected to the arc striking angle. The other end of the arc extinguishing chamber is provided with an arc striking plate, and one end of the arc striking plate extends toward the moving contact.

3. The double-breakpoint miniature circuit breaker according to claim 2, characterized in that: An arc striking convex strip is provided on the side of the arc striking plate facing the moving contact, and the arc striking convex strip automatically extends from the moving contact to the arc extinguishing chamber.

4. The double-breakpoint miniature circuit breaker according to claim 2 or 3, characterized in that: Two arc isolation plates are provided in the housing at both sides of the arc striking plate. Iron sheets are provided on the two arc isolation plates. An arc extinguishing channel communicating between the moving contact and the arc extinguishing chamber is formed between the two arc isolation plates.

5. The double-breakpoint miniature circuit breaker according to claim 4, characterized in that: The two arc isolation plates are respectively provided with grooves matched with the iron sheet, and both ends of the iron sheet have clamping pieces engaged in the grooves, forming a clamping fit between the two arc isolation plates and the iron sheet.

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