CN218677018U - Arc extinguishing mechanism for contact of circuit breaker - Google Patents

Abstract

The utility model provides a circuit breaker contact arc extinguishing mechanism, which comprises a static contact component, an arc extinguishing chamber and a moving contact component; the static contact component comprises a static contact and a static silver point, and the static contact consists of a conductive plate, a contact plate and a wiring board; the current-conducting plates are two inverted U-shaped plates arranged in parallel, and an accommodating space is arranged between the two current-conducting plates; the contact plate is connected between the two conductive plates and is positioned at one end of the bottom of the accommodating space; the lower end of the wiring board is connected between the two current conducting plates and is positioned at the other end of the bottom of the accommodating space, and the upper end of the wiring board extends out of the accommodating space; the static silver point is arranged on the contact plate; the arc extinguishing chamber is arranged in the accommodating space and comprises two arc extinguishing grids arranged in the accommodating space in parallel and a plurality of arc extinguishing sheets which are arranged between the two arc extinguishing grids in an overlapping mode; the arc extinguishing piece is positioned above the lower end of the wiring board. The utility model discloses simple structure, the stable performance is reliable, and the assembly is convenient, and the arc extinguishing is effectual, can effectively prolong circuit breaker life, improves the circuit breaker breaking capacity.

Description

Arc extinguishing mechanism for contact of circuit breaker

Technical Field

The utility model belongs to the technical field of low-voltage apparatus, concretely relates to circuit breaker contact arc extinguishing mechanism.

Background

The circuit breaker is a switching device capable of closing, carrying, and opening/closing a current under a normal circuit condition and a current under an abnormal circuit condition for a predetermined time. The circuit breaker has overload, short circuit and under-voltage protection functions, can protect lines and power supply equipment from being damaged, and can protect fire hazards possibly caused by long-term grounding faults which cannot be detected by overcurrent protection. The molded case circuit breaker comprises a plastic case, an operating mechanism, a contact system and an arc extinguishing system. The circuit breaker is internally provided with a contact system which can execute on-off operation and is composed of a moving contact and a fixed contact. The moving contact and the static contact of the existing common contact system are arranged at one end of the static contact and are approximately parallel, the current direction of the end of the static contact, which is provided with the static contact, is opposite to the current direction of the moving contact, and when the current passes through the moving contact, the moving contact is separated from the static contact by electric repulsion force to generate electric arc, so that the further rise of short-circuit current is limited. Then, the electromagnetic protection mechanism of the circuit breaker can drive the operation mechanism to act, so that the circuit breaker is tripped and opened, electric arcs are extinguished, and short-circuit fault current is cut off.

The arc extinguishing system of the existing molded case circuit breaker is unreasonable in structural design, small in stress area of electric arc, weak in magnetic field, poor in arc extinguishing effect, easy to burn out of a contact and weak in breaking capacity of the circuit breaker, and only the electric arc close to a static contact and a moving contact can be acted by Lorentz force.

SUMMERY OF THE UTILITY MODEL

In order to solve the problem, the utility model aims to provide a static contact arc extinguishing mechanism of circuit breaker of reliable and stable performance, assembly are convenient, the arc extinguishing is effectual, can effectively prolong circuit breaker life, improve the circuit breaker breaking capacity.

The utility model aims at realizing through the following technical scheme:

a circuit breaker contact arc extinguishing mechanism comprises a fixed contact component, an arc extinguishing chamber and a moving contact component, wherein the end part of the moving contact component is provided with a moving silver point; the static contact component comprises a static contact and a static silver point, and the static contact is composed of a conductive plate, a contact plate and a wiring board; the current-conducting plates are two inverted U-shaped plates arranged in parallel, and an accommodating space is formed between the two current-conducting plates; the contact plate is connected between the two conductive plates and is positioned at one end of the bottom of the accommodating space; the lower end of the wiring board is connected between the two conductive plates and is positioned at the other end of the bottom of the accommodating space, and the upper end of the wiring board is bent upwards and extends out of the accommodating space; the static silver point is arranged on the contact plate and corresponds to the dynamic silver point; the arc extinguishing chamber is arranged in the accommodating space and comprises two arc extinguishing grids arranged in the accommodating space in parallel and a plurality of arc extinguishing sheets which are arranged between the two arc extinguishing grids in an overlapping mode; the arc extinguishing piece is positioned above the lower end of the wiring board.

Furthermore, the circuit breaker contact arc extinguishing mechanism also comprises a first insulating sleeve, wherein the first insulating sleeve is a box body clamped in the static contact accommodating space; the top of the first insulating sleeve and one side close to the contact plate are provided with openings and are sleeved outside the lower part of the arc extinguish chamber; a through hole is formed in the bottom of the first insulating sleeve at a position corresponding to the static silver point on the contact plate; the static silver point on the contact plate extends upwards into the first insulating sleeve from the through hole.

Furthermore, all be equipped with the buckle on the face that first insulating cover corresponds two current-conducting plates, first insulating cover passes through the buckle card on the current-conducting plate.

Furthermore, the arc extinguish chamber also comprises a second insulating sleeve, and the second insulating sleeve is two plate bodies which are respectively fixed on the inner side walls of the two arc extinguish grids and positioned above the contact plate; the two second insulating sleeves are not contacted with each other and form a channel above the static silver point between the two second insulating sleeves, and the end part of the movable contact component is rotatably arranged in the channel and can be contacted with or separated from the static silver point.

Furthermore, the moving contact component comprises a third insulating sleeve, and the third insulating sleeve wraps the middle part of the moving contact component and can rotate along with the moving contact component in a channel between the second insulating sleeves.

Further, the arc extinguishing pieces comprise an upper arc extinguishing piece, a plurality of middle arc extinguishing pieces and a lower arc extinguishing piece which are sequentially arranged between the two arc extinguishing grids in an overlapped mode from top to bottom; the arc extinguishing pieces in each arc extinguishing chamber are concave towards one side of the contact plate to form an arc extinguishing groove, the edges of the arc extinguishing grooves facing the contact plate are bevel edges, the bevel edges of the two adjacent arc extinguishing pieces are opposite in inclination direction, and the bevel edges of the two adjacent arc extinguishing pieces are staggered up and down to form a scissor-mouth shape (or a tooth-mouth shape), so that the arc extinguishing chamber is favorable for the arc to enter the arc extinguishing chamber quickly, and the arc is favorable for cutting the arc.

Furthermore, at least one notch is formed in one side, facing the wiring board, of each middle arc-extinguishing piece, and the notches of all the middle arc-extinguishing pieces are aligned up and down. Preferably, the number of the notches is two. The gap can reserve a certain space at the rear part (towards one side of the wiring board) of the arc extinguish chamber, which is beneficial to forming air pressure difference between the contact part of the arc extinguish chamber and the air outlet part of the arc extinguish chamber, reducing air resistance and facilitating the removal of air flow.

Furthermore, one side of the upper arc-extinguishing piece, which faces the contact plate, extends towards the contact plate and covers the arc-extinguishing groove of the uppermost arc-extinguishing piece.

Further, the static contact component also comprises an arc striking sheet, the arc striking sheet is positioned at the bottom inside the arc extinguish chamber, the lower end of the arc striking sheet is fixed at the end part of the contact plate, the upper end of the arc striking sheet extends into the space between the two arc extinguish grids and is positioned in an arc extinguish groove of the arc extinguish sheet at the lower side, the arc striking sheet is used for leading electric arcs generated by the contact of the moving contact and the static contact into the arc extinguish sheet, and arc extinction is carried out in the arc extinguish groove.

The utility model discloses simple structure saves space, and the stable performance is reliable, and the assembly is convenient, and the arc extinguishing is effectual, can effectively prolong circuit breaker life, improves circuit breaker breaking capacity.

Drawings

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

Fig. 1 is a schematic structural diagram of a contact arc extinguishing mechanism of a circuit breaker according to the present invention;

fig. 2 is a diagram of the relationship between the positions of the static contact assembly (split) and the first insulating sleeve and the moving contact assembly in the arc extinguishing mechanism of the circuit breaker contact;

fig. 3 is a schematic structural view of a fixed contact in the contact arc extinguishing mechanism of the circuit breaker of the present invention;

FIG. 4 is a schematic diagram of an electromagnetic force generated by a transverse U-shaped loop formed by a contact plate, an arc and a movable contact to the arc;

FIG. 5 is a schematic diagram of an electromagnetic force generated by an O-shaped loop formed by a conductive plate and a contact plate on an arc;

fig. 6 is a schematic structural diagram of an arc extinguishing chamber in the contact arc extinguishing mechanism of the circuit breaker of the present invention;

fig. 7 is a schematic structural diagram of a first insulating sleeve in the arc extinguishing mechanism of the contact of the circuit breaker according to the present invention;

fig. 8 is a schematic view of an exploded structure of an arc extinguishing chamber in the contact arc extinguishing mechanism of the circuit breaker according to the present invention;

FIG. 9 is a schematic view of the structure of the arc plates in the arc chamber;

shown in the figure: 1-a fixed contact assembly, 11-a fixed contact, 111-a conductive plate, 112-a contact plate, 113-a wiring board, 12-a fixed silver point, 13-an arc striking plate, 2-a first insulating sleeve, 21-a buckle, 3-an arc extinguishing chamber, 31-an arc extinguishing grid, 32-an arc extinguishing plate, 321-an upper arc extinguishing plate, 322-a middle arc extinguishing plate, 323-a lower arc extinguishing plate, 33-a second insulating sleeve, 4-a movable contact assembly, 41-a movable contact, 42-a movable silver point and 43-a third insulating sleeve.

Detailed Description

The following description is provided for illustrative purposes, and other advantages and features of the present invention will become apparent to those skilled in the art from the following detailed description.

It should be understood that the drawings of the present application are only used to match the contents disclosed in the specification, so as to be known and read by those skilled in the art, and not to limit the practical limitations of the present invention, so that the present application does not have any technical significance, and any modification of the structure, change of the ratio relationship, or adjustment of the size should still fall within the scope of the present application without affecting the function and the achievable purpose of the present application. Meanwhile, the terms such as "upper", "lower", "left", "right", "middle", and the like used in the present specification are for convenience of description, and are not intended to limit the scope of the present invention, and changes or adjustments of the relative relationship thereof may be considered as the scope of the present invention without substantial changes in the technical content.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Example 1:

as shown in figure 1, the arc extinguishing mechanism of the contact of the circuit breaker comprises a static contact component 1, an arc extinguishing chamber 3 and a moving contact component 4.

As shown in fig. 2, the stationary contact assembly 1 includes a stationary contact 11 and a stationary silver point 12.

As shown in fig. 3, the stationary contact 11 is composed of a conductive plate 111, a contact plate 112, and a terminal plate 113.

The conductive plates 111 are two inverted U-shaped plates arranged in parallel, and an accommodating space (an opening at the top and two sides of the accommodating space) is formed between the two conductive plates 111. Each conductive plate 111 is comprised of two vertical ribs and an arch transversely fixed between the tops of the two vertical ribs.

The contact plate 112 is connected between the two conductive plates 111 and is located at one end of the bottom of the accommodating space (fixed at the bottom of the vertical rib at one side of the conductive plate 111); contact plate 112 is located below the inverted U-shaped slot of conductive plate 111 (without contacting terminal plate 113).

The lower end of the wiring board 113 is connected between the two conductive plates 111 and located at the other end of the bottom of the accommodating space (fixed at the bottom of the vertical rib at the other side of the conductive plate 111), and the upper end of the wiring board 113 is bent upwards and extends out of the accommodating space (the wiring board 113 is integrally in a Z-shaped structure, the lower transverse section is fixed at the other end of the bottom of the accommodating space, the middle vertical section blocks an opening at one side of the accommodating space, and the upper transverse section extends outwards to be connected with a wire or a conductive plate). A wiring hole is provided at the upper end of the wiring board 113.

As shown in fig. 2, the static silver point 12 is fixed on the contact plate 112 and corresponds to the moving silver point 42 on the moving contact 41.

As shown in fig. 6, the arc extinguishing chamber 3 is disposed in the accommodating space (clamped between the two conductive plates 111), and includes two arc chutes 31 disposed in the accommodating space in parallel, and a plurality of arc extinguishing plates 32 mounted between the two arc chutes 31 in an overlapping manner from top to bottom; the arc chute 31 is shown as a plate with a plurality of air outlets; the arc extinguishing plates 32 are located above the lower end portion (lower lateral section) of the terminal plate 113. The space between the arc-extinguishing grids 31 is through up and down, and the static silver point 12 extends into the space and is positioned at the side edge of the arc-extinguishing piece 32.

As shown in fig. 2, the movable contact component 4 is disposed on a side close to the contact plate 112, and includes a movable contact 41 and a movable silver point 42, the movable silver point 42 is disposed at an end of the movable contact 41 and corresponds to the position of the static silver point 12, and the movable contact 41 can rotate into the arc extinguish chamber 3 (between the two arc extinguish gratings 31), so that the movable silver point 42 contacts the static silver point 12.

The conducting plate 111 of the static contact 11 is made into an inverted U-shaped structure as shown in fig. 3, compared with the conventional U-shaped static contact structure, the upper and lower space is saved, the current of the static contact structure flows in from the wiring board 113, passes through a vertical rib of the conducting plate 111 connected with the wiring board 113, reaches the arch part of the conducting plate 111, flows into another vertical rib of the conducting plate 111 connected with the contact part from the arch part, and then enters the contact plate 112 of the static contact 11, so that the current direction of the contact plate 112 is opposite to that of the moving contact 41, and an electric repulsive force is generated between the static contact 11 and the moving contact 41 in a closing state to enable the moving contact 41 to be opened quickly, thereby having a current limiting effect when the short-circuit current is cut off. In the process of opening the movable contact 41, the arc on the contact plate 112 of the stationary contact 11 and the movable contact 41 form a horizontal U-shaped loop, and as shown in fig. 4, a magnetic field perpendicular to the paper surface is generated in the U-shaped loop, and there is an electromagnetic force toward the left (toward the downward arc extinguishing piece 32) for the arc according to the left-hand rule of the electromagnetic force. Meanwhile, the two vertical ribs, the arched portion and the contact plate 112 of the conductive plate 111 of the static contact 12 form a similar O-shaped loop, as shown in fig. 5, a magnetic field perpendicular to the paper surface is also generated in the O-shaped loop, and according to the left-handed rule of electromagnetic force, the electromagnetic force towards the left (downward arc extinguishing piece 32) is also provided for the electric arc in the frame on the side of the static contact, so that the electric arc rapidly enters the arc extinguishing chamber 3, and the electric arc is extinguished.

Example 2:

this example differs from example 1 in that:

as shown in fig. 1, fig. 2 and fig. 7, the arc extinguishing mechanism of the circuit breaker contact further includes a first insulating sleeve 2, and the first insulating sleeve 2 is a box body clamped in the accommodating space of the static contact 11 and forms a whole with the static contact 11; the top of the first insulating sleeve 2 and one side close to the contact plate 112 are opened and sleeved outside the lower part of the arc extinguish chamber 3; as shown in fig. 2, a through hole is provided at a position corresponding to the static silver point 12 at the bottom of the first insulating sleeve 2, and the static silver point 12 extends upwards into the first insulating sleeve 2 (into the lower side inside the arc extinguish chamber 3) from the through hole. As shown in fig. 7, a snap is provided on a surface of the first insulating sleeve 2 corresponding to the two conductive plates 111, and the first insulating sleeve 2 is snapped on the conductive plates 111 by the snap 21.

As shown in fig. 1, 6 and 8, the arc-extinguishing chamber 3 further includes a second insulating sleeve 33, and the second insulating sleeve 33 is two plate bodies respectively fixed on the inner side walls of the two arc-extinguishing grids 31 and located above the contact plate 112; the two second insulating sleeves 33 are not contacted with each other and form a channel above the static silver point 12 between the two second insulating sleeves, and the end part of the movable contact 41 is rotatably arranged in the channel and can enable the movable silver point 42 at the end part to be contacted with or separated from the static silver point 12.

As shown in fig. 2, the movable contact assembly 4 further includes a third insulating sleeve 43, and the third insulating sleeve 43 is wrapped around the middle portion of the movable contact 41 and can rotate along with the movable contact 41 in the channel between the second insulating sleeves 33.

The existence of the first insulating sleeve 2, the second insulating sleeve 33 and the third insulating sleeve 43 can keep the electric arc between the movable silver point and the static silver point when the contact is disconnected. Preventing the arc from moving back to the lower portion of the movable contact 41.

Example 3:

this example differs from example 1 in that:

as shown in fig. 6 and 8, the arc extinguishing plates 32 include an upper arc extinguishing plate 321, a plurality of middle arc extinguishing plates 322, and a lower arc extinguishing plate 323, which are sequentially installed between the two arc chutes 31 in an overlapping manner from top to bottom.

One side of each arc-extinguishing piece 322, which faces the contact plate 112, is concaved inwards to form an arc-extinguishing groove, the edge of the arc-extinguishing groove, which faces the contact plate 112, is a bevel edge 3221, the bevel edges 3221 of two adjacent arc-extinguishing pieces 322 are opposite in inclination direction, and the bevel edges 3221 of two adjacent arc-extinguishing pieces 322 are staggered up and down to form a scissor-shaped (or tooth-shaped) structure, so that electric arcs can enter the arc-extinguishing chamber quickly, and the electric arcs can be cut easily. The number of the middle arc-extinguishing pieces 322 is 33, and because the opening distance of the circuit breaker is large, the number of the middle arc-extinguishing pieces 322 is greatly increased compared with that of the existing circuit breaker, after the electric arc enters the arc-extinguishing chamber, the number (35) of the arc-extinguishing pieces 32 for dividing the electric arc is increased, the electric arc voltage is greatly improved, and the electric arc extinguishing is facilitated.

The upper arc-extinguishing plates 321 extend toward the contact plate 112 and cover the arc-extinguishing grooves of the uppermost arc-extinguishing plate 322 toward the contact plate 112.

Example 4:

the present embodiment differs from embodiment 3 in that:

two notches 3222 are arranged at one side of each middle arc-extinguishing plate 322 facing the wiring board 113, and the two notches 3222 of all the middle arc-extinguishing plates 322 are aligned up and down. The existence of the gap 3222 can leave a certain space at the rear part (towards one side of the wiring board 113) of the arc extinguish chamber 3, which is beneficial to forming a gas pressure difference between the contact part in the arc extinguish chamber 3 and the gas outlet part of the arc extinguish chamber 3, reducing gas resistance and facilitating the removal of gas flow.

Example 5:

this example differs from any of examples 1 to 4 in that:

as shown in fig. 2, the fixed contact assembly 1 further includes an arc striking sheet 13, the arc striking sheet 13 is located at the bottom inside the arc extinguishing chamber 3, the lower end of the arc striking sheet 13 is fixed at the end of the contact plate 112, the upper end of the arc striking sheet extends between the two arc chutes 31 and is located in the arc extinguishing groove of the middle arc extinguishing sheet 322 at the lower side, and the arc striking sheet 13 is used for guiding the arc generated by the contact between the movable contact 41 and the fixed contact 11 into the arc extinguishing groove of the middle arc extinguishing sheet 322 for arc extinguishing.

It is to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The protection scope of the present invention is not limited to the technical solution disclosed in the specific embodiment, and all the modifications, equivalent replacements, improvements, etc. made by the technical entity of the present invention to the above embodiments all fall into the protection scope of the present invention.

Claims (10)

1. A circuit breaker contact arc extinguishing mechanism comprises a fixed contact component, an arc extinguishing chamber and a moving contact component, wherein the end part of the moving contact component is provided with a moving silver point; the method is characterized in that:

the static contact component comprises a static contact and a static silver point, and the static contact is composed of a conductive plate, a contact plate and a wiring board; the current-conducting plates are two inverted U-shaped plates arranged in parallel, and an accommodating space is formed between the two current-conducting plates; the contact plate is connected between the two conductive plates and is positioned at one end of the bottom of the accommodating space; the lower end of the wiring board is connected between the two conductive plates and is positioned at the other end of the bottom of the accommodating space, and the upper end of the wiring board is bent upwards and extends out of the accommodating space; the static silver point is arranged on the contact plate and corresponds to the dynamic silver point;

the arc extinguishing chamber is arranged in the accommodating space and comprises two arc extinguishing grids arranged in the accommodating space in parallel and a plurality of arc extinguishing sheets which are arranged between the two arc extinguishing grids in an overlapping mode; the arc extinguishing piece is positioned above the lower end of the wiring board.

2. The circuit breaker arc quenching mechanism of claim 1, wherein: the first insulating sleeve is a box body clamped in the static contact accommodating space; the top of the first insulating sleeve and one side close to the contact plate are provided with openings and are sleeved outside the lower part of the arc extinguish chamber; a through hole is formed in the bottom of the first insulating sleeve at a position corresponding to the static silver point on the contact plate; the static silver point on the contact plate extends upwards into the first insulating sleeve from the through hole.

3. The circuit breaker arc quenching mechanism of claim 2, wherein: all be equipped with the buckle on the face that first insulating cover corresponds two current-conducting plates, first insulating cover passes through the buckle card on the current-conducting plate.

4. The circuit breaker arc quenching mechanism of claim 1, wherein: the arc extinguish chamber also comprises a second insulating sleeve; the second insulating sleeves are two plate bodies which are respectively fixed on the inner side walls of the two arc-extinguishing grids and are positioned above the contact plate; the two second insulating sleeves are not contacted with each other and form a channel above the static silver point between the two second insulating sleeves, and the end part of the movable contact component is rotatably arranged in the channel and can be contacted with or separated from the static silver point.

5. The circuit breaker arc quenching mechanism of claim 1, wherein: the moving contact component comprises a third insulating sleeve, and the middle part of the moving contact component is wrapped by the third insulating sleeve.

6. The circuit breaker contact quenching mechanism of any of claims 1-5, wherein: the arc-extinguishing pieces comprise an upper arc-extinguishing piece, a plurality of middle arc-extinguishing pieces and a lower arc-extinguishing piece which are sequentially arranged between the two arc-extinguishing grids in an overlapping mode from top to bottom; each middle arc-extinguishing piece is concave towards one side of the contact plate to form an arc-extinguishing groove, the edge of each arc-extinguishing groove, which faces the contact plate, is a bevel edge, and the bevel edges of two adjacent middle arc-extinguishing pieces are opposite in inclination direction.

7. The circuit breaker arc quenching mechanism of claim 6, wherein: at least one notch is arranged on one side of each middle arc-extinguishing piece, which faces the wiring board, and the notches of all the middle arc-extinguishing pieces are aligned up and down.

8. The circuit breaker arc quenching mechanism of claim 7, wherein: the number of the notches is two.

9. The circuit breaker arc quenching mechanism of claim 6, wherein: the upper arc-extinguishing piece extends towards the contact plate from one side of the upper arc-extinguishing piece towards the contact plate and covers the arc-extinguishing groove of the uppermost arc-extinguishing piece.

10. The circuit breaker arc quenching mechanism of claim 6, wherein: the static contact component also comprises an arc striking sheet, the arc striking sheet is positioned at the bottom inside the arc extinguish chamber, the lower end of the arc striking sheet is fixed at the end part of the contact plate, and the upper end of the arc striking sheet extends into the space between the two arc extinguish grids and is positioned in an arc extinguish groove of the arc striking sheet in the lower side.

Images