CN217691036U

CN217691036U - Short flashover moulded case circuit breaker

Info

Publication number: CN217691036U
Application number: CN202221008831.XU
Authority: CN
Inventors: 张信明
Original assignee: Hebei Bao Kay Electric Co ltd
Current assignee: Hebei Bao Kay Electric Co ltd
Priority date: 2022-04-24
Filing date: 2022-04-24
Publication date: 2022-10-28
Anticipated expiration: 2032-04-24

Abstract

The utility model provides a short arcing moulded case circuit breaker, it includes the circuit breaker body, inserts the silk screen of putting off the arc in the corresponding each looks of circuit breaker body spouts the arc window, the silk screen of putting off the arc is a plurality of, the interval configuration, the silk screen of putting off the arc is the iron wire silk screen of putting off the arc. The utility model discloses can effectively hinder the blowout of electric arc and cut apart, the cooling of electric arc through the silk screen of putting out the arc in the module, reduce the energy of electric arc to finally realize short flashover or the mesh of no flashover. The utility model discloses a cross arc aperture area, quantity and the selection of putting off arc silk screen interval, quantity that set up on the silk screen of putting off arc can adapt to the requirement of different short-circuit current's circuit breaker, form series products. Meanwhile, the arc quenching wire mesh is designed into a composite arc quenching module, so that the arc quenching wire mesh is convenient to replace in daily maintenance.

Description

Short flashover moulded case circuit breaker

Technical Field

The utility model relates to a modified moulded case circuit breaker belongs to circuit protection device technical field.

Background

Plastic case circuit breakers (MCCBs) are important electrical components in industrial and domestic low voltage distribution equipment, and are often used as branch switches of low voltage distribution systems to protect distribution lines from overload and short circuit faults. The short-circuit fault protection is the most important function, and because the short-circuit current of a line is very large during the short-circuit fault, and plasma electric arcs with very large energy can be generated between a movable contact and a fixed contact of the breaker when the breaker breaks the short-circuit current, a plurality of arc extinguishing measures are adopted inside the breaker to extinguish the electric arcs as soon as possible and complete the task of breaking the short-circuit current. When the breaker breaks the short-circuit current, some residual arcs can be sprayed out through an arc spraying window at the upper end of the breaker, the sprayed arcs have certain energy and can damage distribution lines or electrical elements at the upper end of the breaker, and meanwhile, the damage directly influences the design of the power distribution device, so that designers need to consider the arrangement of components inside the distribution box, and further influence the size of the power distribution device. Therefore, the arc generated by the circuit breaker should be as short as possible, and its parameters are one of the important technical indicators that must be considered when designing or applying the circuit breaker (the academic name is called "flashover distance").

At present, two main measures for shortening the flashover distance of the MCCB at home and abroad are as follows: firstly, the structure of an internal arc extinguishing system is changed, but supporting devices need to be redesigned, and further the cost of the circuit breaker is increased; secondly, install the supplementary arc extinguishing module additional in the product outside, but this external dimension that can increase the product equally brings extra difficulty for the installation, simultaneously, also can increase product cost.

In summary, with the requirement of the circuit breaker market for high performance, miniaturization and low cost of products, a new circuit breaker design scheme for shortening the arcing distance is urgently needed in the industry.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a short flashover moulded case circuit breaker, it can cool off electric arc, reduce the electric arc energy, realizes the effect of the short flashover of circuit breaker or no flashover.

The purpose of the utility model is realized by the following technical proposal:

a short-flashover molded case circuit breaker comprises a circuit breaker body, wherein arc extinguishing wire nets are arranged in arc spraying windows corresponding to all phases in the circuit breaker body, and the number of the arc extinguishing wire nets is multiple and are arranged at intervals; the arc quenching silk screen is a silk screen woven by metal wires or a silk screen made of punched metal sheets, and small arc passing holes are formed in the silk screen.

The short-arcing molded case circuit breaker is additionally provided with an arc quenching window frame, the arc quenching window frame is a hollow cavity formed by side plates and n-shaped side covers, and an arc quenching wire mesh is inserted into the cavity to form a composite arc quenching window module; the composite arc spraying window module is arranged on a shell cover or a shell base of the circuit breaker.

In the short flashover molded case circuit breaker, the arc-passing small holes on the arc quenching screen are uniformly arranged at intervals, and the hole patterns of the arc-passing small holes are round holes, square holes or polygonal holes; corresponding arc passing small holes are also arranged on the side plates and the n-shaped side covers.

In the short flashover molded case circuit breaker, the central lines of all the arc-passing small holes in the composite arc extinguishing window module are superposed.

In the short-flashover molded case circuit breaker, the distance between the arc quenching wire nets in the composite arc quenching window module is 0.5-6mm.

In the short-flashover molded case circuit breaker, the area of the small arc-passing hole arranged on the arc-quenching wire mesh is 1-20mm & lt 2 & gt.

Advantageous effects

The utility model provides a compound arc spraying window module can effectively obstruct the blowout of electric arc and through putting out the arc silk screen in the module to cutting apart, the cooling of electric arc, reduces the energy of electric arc to finally realize short flashover or the mesh that does not have the flashover.

The utility model discloses a compound module of putting off arc, through the selection of the wire mesh interval of putting off arc, quantity of crossing arc aperture area, quantity that sets up on the wire mesh of putting off arc, can adapt to the requirement of different short-circuit current's circuit breaker. Meanwhile, the arc quenching wire mesh is designed into a composite arc quenching module, so that the arc quenching wire mesh is convenient to replace in daily maintenance.

Drawings

Fig. 1 is a schematic structural diagram (closing state of the circuit breaker) of the present invention;

fig. 2 is a schematic structural diagram (the circuit breaker is in an open state) of the present invention;

FIG. 3 is a three-phase assembled front view of the composite jet arc window structure;

FIG. 4 is a perspective view of a composite arc-spraying window structure;

FIG. 5 is a schematic single-phase cross-sectional view of a composite arc-spraying window;

FIG. 6 is a schematic structural view of a plate-type arc-spraying window;

FIG. 7 is a front view of a slot-type arc spraying window;

FIG. 8 is a top view of FIG. 7;

fig. 9 is a left side view of fig. 7.

In the drawings, the reference numerals denote: 1. a housing cover; 2. a housing base; 3. an arc-quenching window frame; 3-1 parts of side plates, 3-2 parts of a n-shaped side cover, 3-3 parts of an arc quenching screen, 4 parts of a moving contact; 5. carrying out static contact; 6. an arc extinguishing chamber.

Detailed Description

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

When a short-circuit accident occurs to a power distribution system, the breaker acts rapidly to break short-circuit current, plasma electric arcs with large energy can be generated between a moving contact and a fixed contact of the breaker, at the moment, partial residual electric arcs can be sprayed out through an arc spraying window at the upper end of the breaker, the sprayed electric arcs have certain energy, if the arc spraying is too long, distribution lines or electric appliance elements at the upper end of the breaker can be damaged, and the equipment fault is very troublesome for users.

The utility model discloses a compound arc window structure that spouts of casing (lid) position installation at original MCCB when short-circuit fault electric arc appearing, can effectively hinder consumption, cooling arc energy electric arc energy and restriction flashover distance.

A typical circuit breaker structure is shown in fig. 1-2, and includes a moving contact 4, a static contact 5, an arc extinguishing chamber 6, a housing base 2 and a housing cover 1, and the utility model discloses arc extinguishing window frame 3 has still been add on plastic housing cover 1. The arc quenching window frame 3 is a hollow cavity consisting of a side plate 3-1 and an n-shaped side cover 3-2, and the arc quenching wire mesh 3-3 is inserted into the cavity to form a composite arc quenching window module; the composite arc spraying window module is installed on a shell or a shell base of the circuit breaker.

When the breaker breaks short-circuit current, electric arc between the moving contact and the static contact enters the arc extinguish chamber 6, the energy of the electric arc is greatly weakened after the grid sheet in the arc extinguish chamber is cut, cooled and dissociated, and then the electric arc is sprayed out through the arc extinguish window frame 3 arranged on the shell cover 1. The weakened arc passing through the arc extinguishing chamber 6 is blocked and cooled by passing through the arc extinguishing wire mesh 3-3 in the arc extinguishing window frame 3 in sequence, and the energy is further reduced, thereby reducing the arcing distance and achieving the intended purpose.

The arc quenching wire mesh is a metal wire mesh or a metal sheet arc quenching wire mesh, wherein wire mesh holes can be made of metal wires (such as iron wires) or punched by metal sheets. The shape of the mesh can be square holes, round holes or other polygonal holes.

The utility model discloses constitute compound arc-quenching window module with curb plate 3-1, "pi" form side cap 3-2 and the silk screen 3-3 of putting out the arc to make things convenient for the maintenance to change.

The utility model provides a compound interval of putting out between the arc silk screen among the arc window module is 0.5-6mm, and the aperture area of crossing arc is 1-20mm2, through the selection of the silk screen number of piles of putting out arc, interval and the aperture area and number of putting out arc, can adjust the compound effect of putting out arc in the arc window module of putting out arc. And the arc quenching effect in the composite arc quenching window module can be adjusted by selecting the number of layers and intervals of the arc quenching wire nets, the area of the arc quenching holes and the number of meshes of the arc quenching wire nets so as to correspond to the circuit breakers of different specifications.

The utility model discloses a compound arc extinguishing window module can set up in the three-phase circuit of circuit breaker.

Claims

1. A short-arcing molded case circuit breaker comprises a circuit breaker body and is characterized in that arc extinguishing wire nets (3-3) are arranged in arc spraying windows corresponding to all phases in the circuit breaker body, and the number of the arc extinguishing wire nets (3-3) is multiple and arranged at intervals; the arc quenching silk screen is a silk screen woven by metal wires or a silk screen made of punched metal sheets, and small arc passing holes are formed in the silk screen.

2. The short arcing plastic case circuit breaker according to claim 1, wherein an arc quenching window frame (3) is additionally provided, the arc quenching window frame (3) is a hollow cavity formed by side plates (3-1) and n-shaped side covers (3-2), and the arc quenching wire mesh (3-3) is inserted into the cavity to form a composite arc quenching window module; the composite arc spraying window module is installed on a shell cover or a shell base of the circuit breaker.

3. The short flashover molded case circuit breaker according to claim 1 or 2, wherein the arc passing holes on the arc quenching screen are arranged at regular intervals, and the hole type of the arc passing holes is a circular hole, a square hole or a polygonal hole; corresponding arc passing small holes are also arranged on the side plate (3-1) and the n-shaped side cover (3-2).

4. The short arcing molded case circuit breaker of claim 3, wherein the composite arcing window module has the center lines of the respective arcing holes coinciding.

5. The short arcing molded case circuit breaker of claim 3, wherein a distance between the respective arc-quenching meshes in the composite arc-extinguishing window module is 0.5-6mm.

6. The short arcing molded case circuit breaker according to claim 3, wherein the arc extinguishing wire net is provided with arc passing holes having an area of 1-20mm ² 。