CN216213229U - Flashboard type circuit breaker with larger breaking capacity - Google Patents

Abstract

A flashboard type circuit breaker with larger breaking capacity comprises a circuit breaker body, and after improvement, the flashboard type circuit breaker further comprises a flashboard, an iron core, an armature, a rocker arm, a spring and a guide rail seat fixed on a static contact bracket, wherein the front end of the flashboard corresponds to a gap between a moving contact and a static contact of the circuit breaker, and two side edges of the flashboard are in sliding connection with a sliding rail on the guide rail seat; the upper end of the rocker arm is hinged with the rear end of the flashboard, the lower end of the rocker arm is hinged with the guide rail seat, and the armature is fixed at the middle lower part of the rocker arm; the spring is connected between the rocker arm and the guide rail seat; the iron core is U-shaped, the opening part of the iron core is clamped on a hard connecting wire which is fixedly connected with a base of the circuit breaker and electrically connected with a fixed contact of the circuit breaker, and the opening of the iron core is opposite to the armature. The flashboard can be quickly inserted between the moving contact and the fixed contact when the breaker breaks the short-circuit current, so that the electric arc between the moving contact and the fixed contact is extinguished, the amplification time of the electric arc energy is shortened, the short flashover or no flashover of the breaker is realized, and the capacity of the breaker for breaking the short-circuit current is greatly improved.

Description

Flashboard type circuit breaker with larger breaking capacity

Technical Field

The utility model relates to an arc extinguishing mechanism capable of effectively preventing a large electric arc from being generated between a moving contact and a static contact of a breaker when the breaker breaks short-circuit current, and belongs to the technical field of switches.

Background

Plastic case circuit breakers (MCCBs) are important electrical components in industrial and residential low voltage distribution equipment, and are often used as branch switches for low voltage distribution systems. At present, the MCCB at home and abroad adopts an arc extinguishing chamber technology to cool and extinguish the high-temperature and high-voltage electric arc generated when the short-circuit current is cut off, and the arc extinguishing principle of the technology is as follows: when short-circuit current is cut off, after electric arc is generated between the moving contact and the static contact and is stretched to a certain length to generate larger energy, high-energy electric arc is driven to enter the arc extinguish chamber by adopting magnetic blowing, air blowing or other modes, so that the high-energy electric arc is extinguished under the action of the metal grid sheet in the arc extinguish chamber. The arc extinguishing effect of the method is influenced by factors such as arc extinguishing chamber materials and capacity, contact breaking speed, contact opening distance, contact materials and the like, particularly for the MCCB with a single-breakpoint structure, the capacity of breaking short-circuit current is poor and generally does not exceed 400V and 50kA of alternating current, and if the breaking parameter is increased, the manufacturing cost is greatly increased. And the direct current short-circuit current is not easy to break because of no zero-crossing process.

With the construction and development of power grids and the improvement of the reliability requirements of people on the power grids, a new arc extinguishing scheme is objectively needed to greatly improve the capacity of a breaker for breaking short-circuit current and realize the generalization of alternating current and direct current arc extinguishing devices.

Disclosure of Invention

The utility model aims to provide a flashboard type circuit breaker with larger breaking capacity aiming at the defects of the prior art so as to improve the capacity of the circuit breaker for breaking short-circuit current.

The problems of the utility model are solved by the following technical scheme:

a flashboard type circuit breaker with larger breaking capacity comprises a circuit breaker body, and after improvement, the flashboard type circuit breaker further comprises a flashboard, an iron core, an armature, a rocker arm, a spring and a guide rail seat fixed on a static contact bracket, wherein the front end of the flashboard corresponds to a gap between a moving contact and a static contact of the circuit breaker, and two side edges of the flashboard are in sliding connection with a sliding rail arranged on the guide rail seat; the upper end of the rocker arm is hinged with the rear end of the flashboard, the lower end of the rocker arm is hinged with the guide rail seat, and the armature is fixed at the middle lower part of the rocker arm; the spring is connected between the rocker arm and the guide rail seat; the iron core is U-shaped, the opening part of the iron core is clamped on a hard connecting line which is fixedly connected with a base of the circuit breaker and electrically connected with a fixed contact of the circuit breaker, the opening of the iron core is opposite to the armature, and the suction force between the opening of the iron core and the armature can enable the rocker arm to overcome the elasticity of the spring to rotate so as to insert the gate plate between the fixed contact and the moving contact.

According to the flashboard type circuit breaker with the large breaking capacity, the rear end of the flashboard is hinged with the upper end of the rocker arm through the flashboard pin shaft, and the upper end of the rocker arm is provided with the long round hole corresponding to the flashboard pin shaft.

Above-mentioned flashboard circuit breaker with great breaking capacity, the guide rail seat is formed by left guide rail seat and the concatenation of right guide rail seat, two sides of flashboard respectively with the last slide rail sliding connection of left guide rail seat and right guide rail seat.

Above-mentioned flashboard circuit breaker that has great breaking capacity, the flashboard is straight board or arc, the shape of the last slide rail of guide rail seat and the side shape phase-match of flashboard.

The gate plate type circuit breaker with the large breaking capacity is characterized in that the thickness of the gate plate is 2.5-3.5 mm.

Above-mentioned flashboard circuit breaker with great breaking capacity, the material of flashboard is engineering plastics.

The flashboard can be quickly inserted between the moving contact and the fixed contact when the breaker breaks the short-circuit current, so that the electric arc between the moving contact and the fixed contact is extinguished, the amplification time of the electric arc energy is shortened, the short flashover or no flashover of the breaker is realized, and the capacity of the breaker for breaking the short-circuit current is greatly improved.

Drawings

FIG. 1 is a schematic diagram of the contact in a closed state according to the present invention;

FIG. 2 is an internal schematic view of the contacts of the present invention in a closed state;

FIG. 3 is a schematic diagram of the configuration of the mechanism of the present invention in the open state of the contacts;

FIG. 4 is an internal schematic view of the mechanism of the present invention with the contacts in the open position (with the left rail seat removed);

FIG. 5 is a schematic view of the stationary contact assembly and the core and bracket assembly;

FIG. 6 is a schematic view of the left rail seat structure;

FIG. 7 is a schematic view of the right rail seat construction;

FIG. 8 is a schematic view of a rocker arm, core and shutter combination;

FIG. 9 is a schematic structural view of a stent;

fig. 10 is a schematic view of a stationary contact assembly.

The list of labels in the figure is: 1. a moving contact; 2. a stationary contact assembly; 2-1, static contact; 2-2, hard-wired; 2-3, flexible connection; 3. a guide rail seat; 4. a shutter plate; 5. a support; 6. a rocker arm; 7. an armature; 8. an iron core; 9. a spring; 10. a torsion spring; 11. a moving contact rotating shaft; 12. riveting; A. a moving contact pin; B. a gate pin; C. a fixed contact pin shaft; D. a rocker arm pin shaft.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The utility model relates to an insulation shielding arc extinguishing mechanism which is arranged in a plastic shell type circuit breaker and driven by a preposed magnetic attraction force, at the moment of short circuit fault, at the arc stagnation stage (energy is not amplified) that the moving contact and the static contact of the circuit breaker are not completely opened, the moving contact and the static contact are repelled by an electric repulsion force, and simultaneously, a flashboard is rapidly inserted between the moving contact and the static contact to insulate and shield the circuit breaker. Because the electric arc is extinguished in an insulation shielding mode, the capacity of breaking the short-circuit current of the circuit breaker is greatly improved. The utility model can break AC short-circuit current and also break DC short-circuit current (when breaking DC short-circuit current, the effect is better because of no zero crossing point).

Referring to fig. 1 to 10, the utility model mainly comprises a circuit breaker body, a moving contact 1 arranged in the circuit breaker, a static contact component 2 (comprising a static contact 2-1, a hard connecting wire 2-2 and a soft connecting wire 2-3), a guide rail seat 3 (comprising a left guide rail seat and a right guide rail seat), a flashboard 4, a bracket 5, a rocker arm 6, an armature 7, an iron core 8, a spring 9, a torsion spring 10 and a moving contact rotating shaft 11.

The moving contact 1 is arranged in a moving contact rotating shaft 11 through a moving contact pin shaft A (wherein, a moving contact pressure torsion spring is also arranged, which is not marked), and a static contact 2-1 in the static contact component 2 and a torsion spring 10 are arranged on a bracket 5 through a static contact pin shaft C;

the cross section of the iron core is U-shaped, the iron core is fixed at the lower part of the hard connecting wire 2-2 of the fixed contact component 2 during installation, the opening part of the iron core is clamped on the straight-line section of the bevel edge at the lower part of the hard connecting wire 2-2, and the opening is opposite to the armature 7, so that the driving force of a magnetic field can be improved, the suction force to the armature 7 is enhanced, and the shielding action speed of the rocker arm 6 driving the flashboard 4 is accelerated.

The left guide rail seat and the right guide rail seat are provided with the groove-shaped slide rails which respectively correspond to the two sides of the flashboard 4, so that the flashboard 4 can slide in the groove-shaped slide rails, and the slide rail pair is adopted, so that the running stability of the flashboard 4 can be improved, the explosion and randomness of short-circuit current magnetic field force can be overcome, and the impact resistance can be improved.

Rocker 6 and armature 7 are a riveting assembly, and flashboard 4 is installed in rocker 6 upper end through flashboard round pin axle B, and rocker 6 is installed on left and right guide rail seat through rocker round pin axle D, and spring 9 one end is installed on rocker 6, and one end is installed on guide rail seat 3, and support 5 is installed together with the left and right guide rail seat of riveting firmly together with rivet 12 and is fixed on the switch base, and rocker 6 can the horizontal hunting, and the hunting both ends are by left and right guide rail seat 3 spacing. The upper end of the rocker arm 6 is designed into a long round hole shape so as to make up for the displacement difference caused by different arc tracks of the groove-shaped slide rails arranged on the left and right guide rail seats 3 and the upper end of the rocker arm 6. Under normal opening and closing conditions, the rocker arm 6 and the armature 7 are positioned at the positions (the movable contact and the fixed contact are in a closing contact state) in the figure 1 under the action of the spring 9, and the contact arc extinguishing mechanism is in an open state. When the short-circuit fault current occurs to the line, because the current directions of the static contact 2-1 and the moving contact 1 in the static contact component 2 are opposite, therefore, the static contact 2-1 and the moving contact 1 in the static contact component 2 are quickly repelled by overcoming the pressure of the torsion spring 10 and the moving contact and the action of the torsion spring due to the electric repulsion force generated (the static contact 2-1 in the static contact component 2 is connected with other components through the soft connecting wire 2-3 and the hard connecting wire 2-2 in turn), meanwhile, because the iron core 8 generates electromagnetic attraction to the armature 7 under the action of a magnetic field generated by large current, the armature 7 overcomes the elasticity of the spring 9 to drive the rocker arm 6 to generate anticlockwise rapid swing, thereby driving the flashboard 4 to move leftwards and rapidly in the groove-shaped slide rail arranged on the left and right guide rail seats 3, and rapidly inserting between the moving contact and the static contact while repelling the moving contact and the static contact, thereby playing the role of rapid shielding and arc extinguishing. Meanwhile, the magnetic tripping device of the MCCB pushes the switch tripping mechanism to act to drive the moving contact rotating shaft 11 to act, and the moving contact 1 and the static contact 2-1 of the circuit breaker are completely opened to finish the breaking process of the MCCB. Since the short-circuit current is cut off, the strong electromagnetic field disappears, and the shutter 4 is restored to its original position.

The gate plate 4 of the utility model is made of insulating material with high dielectric coefficient, and the thickness is about 3 mm.

The moving contact 1 and the static contact component 2 both adopt a rotating hinge type repulsion structure. The electric conductor of the static contact component 2 at least comprises a straight section which is basically parallel to the moving contact 1, the directions of currents in the straight section of the static contact component 2 and the moving contact 1 are opposite, when a fault occurs, short-circuit currents with opposite directions flow through the straight section of the static contact component 2 and the moving contact 1, electric repulsion is generated between the static contact component 2 and the moving contact 1, the moving contact 1 rotates clockwise by taking the moving contact shaft pin A as an axis and is repelled, and the static contact 2-1 in the static contact component 2 rotates counterclockwise by taking the static contact shaft pin C as an axis and is repelled.

The gate plate 4 is made of high-strength and high-temperature-resistant engineering plastic materials. The number of times (3 times at most) of effectively breaking the short-circuit current specified by the product standard can be ensured.

Due to the technical scheme adopted by the MCCB, the following technical progress can be obtained:

1, the capacity of breaking short-circuit current of a product can be greatly improved;

2. the purpose of alternating current and direct current is achieved;

3. when the fault short-circuit current is cut off, the further expansion of the arc energy can be limited, so that short arcing or no arcing of the product can be realized.

Claims (6)

1. A flashboard type circuit breaker with larger breaking capacity comprises a circuit breaker body and is characterized by further comprising a flashboard (4), an iron core (8), an armature (7), a rocker (6), a spring (9) and a guide rail seat (3) fixed on a static contact bracket (5), wherein the front end of the flashboard (4) corresponds to a gap between a moving contact (1) and a static contact (2-1) of the circuit breaker, and two side edges of the flashboard (4) are in sliding connection with a sliding rail arranged on the guide rail seat (3); the upper end of the rocker arm (6) is hinged with the rear end of the flashboard (4), the lower end of the rocker arm is hinged with the guide rail seat (3), and the armature iron (7) is fixed at the middle lower part of the rocker arm; the spring (9) is connected between the rocker arm (6) and the guide rail seat (3); the suction force between the iron core (8) and the armature (7) can enable the rocker arm (6) to overcome the elasticity of the spring (9) to rotate so as to insert the flashboard (4) between the static contact (2-1) and the moving contact (1); the iron core (8) is U-shaped, the opening part of the iron core is clamped on a hard connecting wire which is fixedly connected with the base of the circuit breaker and is electrically connected with a static contact (2-1) of the circuit breaker, and the opening of the iron core (8) is opposite to the armature (7).

2. The paddle circuit breaker with higher breaking capacity according to claim 1, wherein the rear end of the paddle (4) is hinged to the upper end of the rocker arm (6) through a paddle pin shaft, and the upper end of the rocker arm (6) is provided with a long round hole corresponding to the paddle pin shaft.

3. The gate type circuit breaker with large breaking capacity according to claim 1 or 2, wherein the guide rail seat (3) is formed by splicing a left guide rail seat and a right guide rail seat, and two side edges of the gate plate (4) are respectively connected with sliding rails on the left guide rail seat and the right guide rail seat in a sliding manner.

4. The plate circuit breaker with larger breaking capacity according to claim 3, wherein the shutter plate (4) is a straight plate or an arc plate, and the shape of the sliding rail on the guide rail seat (3) is matched with the shape of the side edge of the shutter plate (4).

5. The plate circuit breaker with high breaking capacity according to claim 4, wherein the thickness of the shutter plate (4) is 2.5-3.5 mm.

6. The plate circuit breaker with high breaking capacity according to claim 5, wherein the material of the shutter plate (4) is engineering plastic.

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