A kind of breaker of plastic casing with powerful disjunction short circuit current ability
Technical field
The present invention relates to a kind of breaker of plastic casing with strong short circuit current breaking capacity, belong to switching technique field.
Background technology
Moulded case circuit breaker (MCCB) is the industrial important electric elements with civilian low-voltage distribution apparatus, is used as more
The branch switch of low-voltage distribution system protection.Wherein short trouble protection is its most important function, line during due to short trouble
The short circuit current on road is very big, breaker can be produced between its dynamic and static contact in disjunction short circuit current the very big grade of energy from
Daughter electric arc, only could be rapidly by arc extinction by default arc-extinguishing unit, and breaker could complete disjunction short circuit electricity
The task of stream.
At present, caused HTHP electric arc enters when domestic and international MCCB uses arc-chutes technology to disjunction short circuit current
Row cooling and extinguishing, the arc quenching principle of this technology are:During disjunction short circuit current, treat to produce electric arc between dynamic and static contact and draw
After growing to the corresponding amplification of certain length, energy, arc-chutes are entered using magnetic field electro-dynamic force or other means driving high energy arc, made
Extinguish under the cooling effect of its metal grid in arc-chutes.The arc quenching effect of this method by such as arc-chutes material, touch
Head cut-offs the influence of the factors such as speed, clearance between open contacts, contact material, especially for the breaker of single-break structure, its disjunction
The ability of short circuit current is poor, be usually no more than exchange 400V, 50kA, and direct-current short circuit electric current due to no zero passage process more
It is not easy disjunction.
With the raising that the construction and development and people of power network are required electric network reliability, a kind of new go out objectively is needed
Arc scheme, to greatly improve the ability of MCCB disjunction short circuit currents.
The content of the invention
It is an object of the invention to the drawback for prior art, there is provided a kind of with powerful disjunction short circuit current ability
Breaker of plastic casing, to improve the breaking capacity of short circuit current.
Problem of the present invention is realized with following technical proposals:
A kind of breaker of plastic casing with powerful disjunction short circuit current ability, including shell, static contact, moving contact, dropout
Mechanism and arc-chutes, insulation arc-control device is also included in composition, and the insulation arc-control device includes yoke, support base, torsion spring, rank
Iron and an insulating shroud without antetheca, the yoke are fixed on the static contact of breaker and are located at dynamic and static contact face
Lower section;The support base is fixed on static contact and positioned at the bottom of yoke;Between an insulating shroud and dynamic and static contact
Gap it is corresponding, an insulating shroud passes through the rotating shaft through torsion spring centre bore and support base and is rotatablely connected;The one of the torsion spring
In an insulating shroud, the other end is pressed on the steady pin on support base side pressure;The armature is fixed in an insulating shroud simultaneously
It is corresponding with yoke.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, an insulating shroud are semi-closed structure,
Linked together and formed by top plate, two side walls and rear wall, front opening, the top plate of an insulating shroud and dynamic and static contact
Between gap it is corresponding, the armature is fixed on the rear wall of an insulating shroud and corresponding with yoke.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, the axis of the rotating shaft connect with dynamic and static contact
The perpendicular bisector of contacting surface intersects vertically.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, the rear wall of an insulating shroud, which is provided with, to be led to
Air holes.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, insulation is provided between the yoke and static contact
Backing plate.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, the torsion spring and rotating shaft are respectively provided with two, it
Be symmetrically mounted on the both sides of support base.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, arc-chutes are additionally provided with the shell and magnetic is protected
Protect electrical apparatus release.
The above-mentioned breaker of plastic casing with powerful disjunction short circuit current ability, an insulating shroud pass through screw with armature
It is fixed as one.
The present invention is additionally arranged an insulating shroud, and an insulating shroud can be moved rapidly in the moment of breaker disjunction short circuit current
Make, between insertion moving contact and static contact, make just caused arc extinction or reduction between dynamic and static contact, thus contract
The short amplification time of arc energy, reduces gathering for arc energy, realizes the short arcing of breaker or without arcing.This hair
Bright to take two-stage arc extinguishing, the electric arc after initial stage an insulating shroud auxiliary extinction of arc can be introduced into arc-chutes and continue follow-up go out
Arc operates, and so as to substantially increase the arc extinguishing ability of breaker, also substantially increases the ability of breaker disjunction short circuit current.
Brief description of the drawings
Fig. 1 is the "on" position schematic diagram of the present invention;
Fig. 2 is the view when contact reprimand of the present invention is opened;
Fig. 3 is the gate-dividing state schematic diagram of the present invention;
Fig. 4 is the structural representation of insulation arc-control device;
Fig. 5 is C-C sectional views;
Fig. 6 is the structural representation of support base;
Fig. 7 is the structural representation of an insulating shroud and armature.
Each list of reference numerals is in figure:1st, static contact;2nd, moving contact;3rd, an insulating shroud;3-1, armature;4th, yoke;5th, prop up
Support seat;5-1, rotating shaft;5-2, steady pin;6th, torsion spring;7th, screw;8th, insulating pad;9th, handle;10th, magnetic protection electrical apparatus release;10-
1st, tripping mechanism;11st, arc-chutes;12nd, shell;A, bearing pin.
Embodiment
The invention will be further described below in conjunction with the accompanying drawings.
The present invention is that an insulation arc-control device driven by electromagnetic force is installed at original MCCB static contact position, short
The moment that road failure occurs, the not yet full opening of electric arc lag phase (energy not yet amplifies) of the dynamic and static contact of breaker, move,
While static contact is opened by electrodynamic repulsion force reprimand, an insulating shroud is covered on the static contact of breaker.Using insulation shielding mode
Extinguish electric arc, so as to which the ability of breaker disjunction short circuit current greatly improved.
Referring to Fig. 1~Fig. 7, the invention mainly comprises the static contact 1 in engineering plastics shell 12, moving contact 2, magnetic
Protect electrical apparatus release 10, tripping mechanism 10-1, insulation arc-control device, arc-chutes 11 and handle 9.Wherein, insulate arc-control device bag
Include an insulating shroud 3 for being arranged on the position of static contact 1, armature 3-1, yoke 4, support base 5, rotating shaft 5-1, steady pin 5-2, torsion spring
6 and insulating pad 8.
An insulating shroud 3 and armature 3-1 is an assembly, under normal circumstances, an insulating shroud 3 and armature 3-1 combination
Body moves clockwise to open mode (Fig. 1 positions), the right side of an insulating shroud 3 at dynamic and static contact in the presence of torsion spring 6
Side, an insulating shroud 3 can overcome the elastic force of torsion spring 6 under external force using the rotating shaft 5-1 on support base 5 as axial left swing
It is dynamic.When short-circuit current occurs in circuit, due to static contact 1 with the sense of current of moving contact 2 on the contrary, therefore producing electrodynamic repulsion force
By static contact 1 and moving contact 2, quickly reprimand opens (moving contact 2 is swung up using bearing pin A as axle), while yoke 4 is magnetized by electromagnetic field
Very big suction is produced to armature 3-1 afterwards, an insulating shroud 3 and armature 3-1 assembly overcomes the elastic force of torsion spring 6 with rotating shaft 5-
1 rotates counterclockwise for axle, and the top plate of an insulating shroud 3 is rapidly inserted into dynamic and static while dynamic and static contact is opened by electrodynamic repulsion force reprimand
Between contact (Fig. 2 positions), play a part of rapid insulation shielding arc extinguishing, at the same time, MCCB magnetic protection electrical apparatus release 10 pushes away
Dynamic its switch trip mechanism 10-1 actions, moving contact 2 and the static contact 1 of switch are opened completely, complete MCCB short circuit breaking mistake
Journey.Afterwards because short circuit current is cut off, strong-electromagnetic field disappears, the homing under the elastic force effect of torsion spring 6 of an insulating shroud 3
(Fig. 3 positions).
Rotating hinge chain type repulsion structure is used between static contact 1 and moving contact 2.The bonding jumper of static contact 1 comprises at least one
Section flat segments parallel with moving contact, the sense of current in the flat segments of static contact 1 and moving contact 2 is on the contrary, the flat segments of static contact 1
Length produce when being more than or equal to short circuit current flow in moving contact and static contact and make the repulsion that dynamic and static contact repels each other out required for
Length.Insulating pad 8 prevents electric current from directly being flowed into from the short circuit of lower end yoke 4.When an error occurs, short circuit electricity in opposite direction
When stream flows through static contact flat segments and moving contact, electrodynamic repulsion force is produced between static contact 1 and moving contact 2 so that moving contact 2 with
Bearing pin A is that axle is denounceed out rotationally clockwise.
The present invention is provided with air vent on the rear wall of an insulating shroud, it is therefore an objective to the electric arc between isolation dynamic/static contact is ensured
While, the resistance in an insulating shroud motion is reduced as far as possible.The gross area of each air vent accounts for the 30%- of the rear wall gross area
50%.The wall thickness of an insulating shroud is 2-5 millimeters.In the lower sidewall of an insulating shroud and rear wall bottom close to the side of arc-chutes
To through hole is provided with, arc-chutes are led to pilot arc.
An insulating shroud 3 is using high intensity, resistant to elevated temperatures engineering plastic materials.It can ensure effectively to divide as defined in product standard
The number (most 3 times) of disconnected short circuit current.
Improve and reduce the Capacity design of arc-chutes 11, extinguish remaining electric arc for cooling down;Handle 9 is installed on shell 12
End, for normal occlusion sub-switching operation.
The arc-control device that insulate forms two-stage arc-control device with arc-chutes 11, and insulation arc-control device is not yet complete in dynamic and static contact
Arc extinguishing during full opening, and arc-chutes 11 are then to have good extinguishing remnants arcings after dynamic and static contact is opened completely.
Because MCCB uses above technical scheme, following technological progress can be obtained:
1 can greatly improve the ability of product disjunction short circuit current;
2. the general purpose of AC and DC can be reached;
3. in disjunction failed shorted electric current, the further expansion of arc energy can be limited, so as to which the short of product can be realized
Arcing or without arcing.