A new arc extinguishing magnetic blowout device for molded case circuit breakers

Abstract

The utility model discloses a novel arc extinguishing magnetic blowing device for a molded case circuit breaker, which comprises a circuit breaker housing base, a static contact, a boss and a magnetic blowing piece. The circuit breaker housing base is provided with a static contact mounting groove, the static contact comprises a front U-shaped portion and a tail connecting end, a square boss is provided at the center of the static contact mounting groove, a slot is provided at the center of the boss, the magnetic blowing piece comprises an integrally connected top piece and an inserting piece, the top piece is horizontally arranged, the inserting piece is vertical to the top piece, the inserting piece is wide at the top and narrow at the bottom, and is interference-connected with the slot, the top of the inner circle of the static contact U-shaped portion is in contact with the upper end of the top piece, a downward limiting protrusion is provided, a limiting hole is provided at the corresponding position of the top piece, the static contact U-shaped portion and the magnetic blowing piece form a ring, and compared with the current magnetic blowing structure of the molded case circuit breaker, the magnetic blowing piece has a reasonable and simple structural design, the inserting piece is wide at the top and narrow at the bottom, and the magnetic blowing piece is stably connected to the base; the magnetic blowing piece top piece is provided with a limiting hole, and the connection and contact with the static contact U-shaped portion is more stable and reliable.

Description

Technical Field

[0001] The utility model relates to the technical field of low-voltage electrical appliances, in particular to a novel arc-extinguishing magnetic blowout device for a molded case circuit breaker. Background Art

[0002] Molded case circuit breakers are devices used for long-time delay overload and instant short circuit. The moving contact and static contact of the circuit breaker are generally equipped with arc extinguishing devices, which are mainly used to extinguish the arc generated during the opening and closing process. At present, in low-voltage plastic case circuit breaker products, an annular magnetic blowing structure is provided at the static contact position, which includes a U-shaped static contact and a magnetic blowing sheet arranged in the static contact annular cavity. The current structural form is that multiple magnetic blowing sheets are riveted together, and after adding an insulating layer to the upper or lower end surface of the magnetic blowing sheet and the static contact, it is installed at the lower end of the static contact. The existing problems are: complex structure, cumbersome processing and assembly process, etc., and unreliable fixation. Summary of the invention

[0003] The purpose of the utility model is to solve the above technical problems and provide a novel arc extinguishing magnetic blowing device for molded case circuit breaker, which has reasonable and ingenious structural design, convenient installation, firmness and stability, and long practical life.

[0004] In order to achieve the above-mentioned invention object, the technical solution adopted by the utility model is:

[0005] A novel arc extinguishing magnetic blowing device for molded case circuit breaker is arranged below the arc extinguishing chamber of the molded case circuit breaker. The device comprises a circuit breaker housing base, a static contact, a boss, and a magnetic blowing piece. The circuit breaker housing base is provided with a static contact mounting groove. The static contact comprises a front U-shaped portion and a tail connecting end. A square boss is provided at the center of the static contact mounting groove. A slot is provided at the center of the boss. The magnetic blowing piece comprises an integrally connected top piece and an insert piece. The top piece is arranged horizontally, and the insert piece is perpendicular to the top piece. The insert piece is wide at the top and narrow at the bottom, and is interference-connected with the slot. The top of the inner circle of the U-shaped portion of the static contact is in contact with the upper end of the top piece, and a downward limiting protrusion is provided. A limiting hole is provided at the corresponding position of the top piece. The U-shaped portion of the static contact and the magnetic blowing piece form a ring.

[0006] The end of the U-shaped portion of the stationary contact is inclined downward, and a gap is provided between the end and the lower end plate of the U-shaped portion of the stationary contact.

[0007] A square hole is arranged in the middle of the plate at the lower end of the U-shaped portion of the stationary contact to facilitate passage through the boss.

[0008] The boss is integrally connected to the base of the circuit breaker housing and is made of insulating material. The upper end surface of the boss is flat, and the distance between the upper end surface of the boss and the top of the U-shaped portion of the installed static contact is slightly greater than the thickness of the top plate of the magnetic blow sheet.

[0009] The shape of the static contact installation groove is similar to the shape of the lower end surface of the static contact. The circuit breaker housing base is provided with an installation fixing hole. When the static contact is fixed to the housing base, the lower end surface of its U-shaped part and the front part of the connecting end are fitted with the installation groove.

[0010] The upper end surface of the U-shaped portion of the static contact is provided with a contact point, and a gap is provided between the end of the U-shaped portion and the connecting end to facilitate accommodating the lower part of the arc extinguishing grid in the arc extinguishing chamber.

[0011] The beneficial effects of the utility model are as follows: compared with the current magnetic blowing structure of the molded case circuit breaker, the magnetic blowing piece structure is reasonably and simply designed, the plug-in piece is wide at the top and narrow at the bottom, and forms an interference fit connection with the base boss, so that the connection between the magnetic blowing piece and the base is stable; the length of the top piece of the magnetic blowing piece is shortened and a limiting hole is provided, so that the magnetic blowing piece is lighter, and at the same time the connection contact with the U-shaped part of the static contact is more stable and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic diagram of the cross-sectional structure of an embodiment of the utility model;

[0013] Figure 2 It is a structural schematic diagram of a magnetic blown sheet;

[0014] Figure 3 Schematic diagram of the traditional magnetic blowing structure.

[0015] 2-installation groove, 3-moving contact, 4-arc extinguishing grid, 5-magnetic blow plate, 6-boss, 7-slot, 11-U-shaped part, 9-tail connecting end, 51-top plate, 52-insertion plate, 53-limiting hole. DETAILED DESCRIPTION

[0016] As attached Figure 1-2 A novel arc extinguishing magnetic blowing device for molded case circuit breaker is shown, which is arranged below the arc extinguishing chamber of the molded case circuit breaker. The arc extinguishing chamber of the circuit breaker is provided with a movable moving contact 3, and an arc extinguishing grid 4 is provided on one side above the static contact. The arc extinguishing magnetic blowing device for the molded case circuit breaker includes a circuit breaker housing base, a static contact, a boss 6, and a magnetic blowing sheet 5. The circuit breaker housing base is provided with a static contact mounting groove 2, the static contact includes a front U-shaped portion 11 and a rear connecting end 9, and a square boss 6 is provided at the center of the static contact mounting groove 2. A slot 7 is provided at the center of the boss 6. The magnetic blow piece 5 includes a top piece 51 and an insert piece 52 which are integrally connected. The top piece 51 is arranged horizontally, and the insert piece 52 is perpendicular to the top piece 51. The insert piece 52 is wide at the top and narrow at the bottom, and is interference-connected with the slot 7, so that the connection between the magnetic blow piece 5 and the base is more stable and reliable. The top of the inner circle of the U-shaped portion 11 of the static contact is in contact with the upper end of the top piece 51, and is provided with a downward limiting protrusion. A limiting hole 53 is provided at the corresponding position of the top piece 51. The U-shaped portion of the static contact and the magnetic blow piece 5 form a ring.

[0017] The end of the U-shaped portion of the stationary contact is inclined downward, and a gap is provided between the end and the lower end plate of the U-shaped portion of the stationary contact.

[0018] A square hole is provided in the middle of the plate at the lower end of the U-shaped portion of the stationary contact to facilitate the passage of the boss 6.

[0019] The boss 6 is integrally connected to the base of the circuit breaker housing and is made of insulating material. The upper end surface of the boss 6 is a plane. The distance between the upper end surface of the boss 6 and the top of the U-shaped portion of the static contact after installation is slightly greater than the thickness of the top plate 51 of the magnetic blow plate 5.

[0020] The shape of the static contact mounting groove 2 is similar to the shape of the lower end surface of the static contact. The base of the circuit breaker housing is provided with a mounting fixing hole to facilitate fixing the connecting end of the static contact. When the static contact is fixed to the housing base, the lower end surface of its U-shaped portion and the front part of the connecting end are in contact with the mounting groove 2.

[0021] The upper end surface of the U-shaped portion of the static contact is provided with a contact point, and a gap is provided between the end of the U-shaped portion and the connecting end to facilitate accommodating the lower part of the arc extinguishing grid 4 in the arc extinguishing chamber.

[0022] The magnetic blow sheet 5 is an iron magnetic blow sheet 5. After the magnetic blow sheet 5 is provided with a positioning hole, its weight can be reduced.

[0023] When a short-circuit high current flows through the circuit breaker, a strong magnetic field is formed around the U-shaped static contact containing the magnetic blow piece 5, which quickly blows the arc generated during the breaking process into the arc extinguishing chamber, speeding up the arc extinguishing speed and greatly improving the breaking capacity of the circuit breaker.

[0024] The above is only a preferred embodiment of the present utility model. It should be pointed out that for ordinary technicians in the technical field, several improvements can be made without departing from the principle of the present utility model. These improvements should also be regarded as within the scope of protection of the present utility model without paying creative labor.

Claims

1. A new arc extinguishing magnetic blowout device for molded case circuit breakers, characterized in that: It includes a circuit breaker housing base, a static contact, a boss, and a magnetic blow piece. The circuit breaker housing base is provided with a static contact mounting groove. The static contact includes a front U-shaped portion and a tail connecting end. A square boss is provided at the center of the static contact mounting groove. A slot is provided at the center of the boss. The magnetic blow piece includes an integrally connected top piece and an insert piece. The top piece is horizontally arranged, and the insert piece is perpendicular to the top piece. The insert piece is wide at the top and narrow at the bottom, and is interference-connected with the slot. The top of the inner ring of the U-shaped portion of the static contact is in contact with the upper end of the top piece, and is provided with a downward limiting protrusion. A limiting hole is provided at the corresponding position of the top piece. The U-shaped portion of the static contact and the magnetic blow piece form a ring.

2. The novel arc extinguishing magnetic blowout device for molded case circuit breaker according to claim 1 is characterized in that: The end of the U-shaped portion of the stationary contact is inclined downward, and a gap is provided between the end and the lower end plate of the U-shaped portion of the stationary contact.

3. The novel arc extinguishing magnetic blowout device for molded case circuit breaker according to claim 1 is characterized in that: A square hole is arranged in the middle of the plate at the lower end of the U-shaped portion of the stationary contact to facilitate passage through the boss.

4. The novel arc extinguishing magnetic blowout device for molded case circuit breaker according to claim 1 is characterized in that: The boss is integrally connected to the base of the circuit breaker housing and is made of insulating material. The upper end surface of the boss is a plane. The distance between the upper end surface of the boss and the top of the U-shaped portion of the installed static contact is greater than the thickness of the top plate of the magnetic blow sheet.

5. The novel arc extinguishing magnetic blowout device for molded case circuit breaker according to claim 1 is characterized in that: The shape of the static contact installation groove is similar to the shape of the lower end surface of the static contact. The circuit breaker housing base is provided with an installation fixing hole. When the static contact is fixed to the housing base, the lower end surface of its U-shaped part and the front part of the connecting end are fitted with the installation groove.

6. The novel arc extinguishing magnetic blowout device for molded case circuit breaker according to claim 1 is characterized in that: The upper end surface of the U-shaped portion of the static contact is provided with a contact point, and a gap is provided between the end of the U-shaped portion and the connecting end to facilitate accommodating the lower part of the arc extinguishing grid in the arc extinguishing chamber.

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