CN217655826U - Electromagnetic structure of direct current relay - Google Patents

Abstract

The utility model relates to a relay especially relates to a high voltage direct current relay. An electromagnetic structure of a direct current relay comprises a ceramic component and a metal sleeve, wherein the ceramic component at least comprises a fixed contact, a ceramic body and a Kovar part, an arc extinguishing cover is arranged below the ceramic body, a reciprocating motion mechanism is arranged below the fixed contact, external magnetic steel is arranged on the outer side of the arc extinguishing cover, middle magnetic steel is embedded in the arc extinguishing cover, an upper magnetizer is arranged between the middle magnetic steel and the ceramic body, the external magnetic steel is intersected with an extended long line of a connecting line of the two fixed contacts, and the magnetic field directions of the middle magnetic steel and the external magnetic steel are consistent and are perpendicular to the current direction flowing through the fixed contact. The utility model discloses not only can make direct current relay extinguish electric arc fast and can reduce the sticky risk of even of contact, improve direct current relay's electric life and reliability.

Description

Electromagnetic structure of direct current relay

Technical Field

The utility model relates to a relay especially relates to a direct current relay.

Background

In recent years, new energy automobiles, charging piles and energy storage industries are rapidly developed, products and technologies related to direct current electricity are more widely applied, a direct current relay is an essential element for controlling the connection and disconnection of a direct current circuit, and the market demand of the direct current relay is greatly increased every year.

The direct current relay is an electromagnetic system consisting of a coil and an iron core and used as a control and execution component to drive a mechanism in the relay to switch on or off a movable contact and a fixed contact so as to realize a switching function.

Under the condition of load, the moving contact and the fixed contact of the direct current relay can generate electric arcs at the moment of contact or disconnection, the intensity of the electric arcs is higher when the load current is higher, and the direct current relay can be exploded or burnt if the electric arcs cannot be quickly extinguished; in a high-voltage direct-current electrical system (such as an electrical system of a new energy automobile), a short-circuit current far larger than a rated load current is generated when a power battery supplies power or the system fails, a fuse normally protects the short-circuit current, and before the fuse breaks the short-circuit current, a direct-current relay cannot bear an instantaneous large current, so that a contact is stuck to cause a fault.

Disclosure of Invention

The utility model aims at solving the above-mentioned defect of prior art, provide a direct current relay's electromagnetic structure. The utility model discloses not only can make direct current relay extinguish electric arc fast and can reduce the sticky risk of even of contact, improve direct current relay's electric life and reliability.

The utility model discloses a realize like this, a direct current relay's electromagnetic structure, including ceramic subassembly and metal sleeve, ceramic subassembly includes static contact, ceramic body and kovar piece at least, is equipped with the arc-extinguish chamber below the ceramic body, has a reciprocating motion's motion below the static contact, is equipped with the outer magnet steel in the arc-extinguish chamber outside, has middle magnet steel at the embedded middle magnet steel that has of arc-extinguish chamber, has the magnetizer between this middle magnet steel and the ceramic body, the outer magnet steel intersects with the extension length line of two static contact lines, middle magnet steel is unanimous with the magnetic field direction of outer magnet steel and is perpendicular with the current direction of flowing through the static contact.

In the motion mechanism, a shaft sequentially passes through a push rod, a moving contact, a lower magnetizer, a contact spring, an iron core spring and a moving iron core, and clamp springs are arranged at two ends of the shaft to limit the push rod and the moving iron core respectively.

In the electromagnetic structure of the direct current relay, the upper magnetizer and the lower magnetizer are in U-shaped structures and surround the moving contact to form a magnetic conductive loop.

The electromagnetic structure of the direct current relay is characterized in that a square groove is formed in the middle of the arc extinguishing cover, the middle magnetic steel is placed in the square groove, and the U-shaped upper magnetizer surrounds the top surface and the two side surfaces of the middle magnetic steel.

According to the electromagnetic structure of the direct-current relay, the outer magnetic steel is provided with the metal sheet, and the metal sheet is made of a magnetic conductive material and used for shielding a magnetic field of the outer magnetic steel.

According to the electromagnetic structure of the direct-current relay, a rubber ring is arranged between the arc-extinguishing cover and the ceramic body and used for electrically isolating the upper magnetizer and the static contact.

In the electromagnetic structure of the direct current relay, the ceramic component and the metal sleeve are tightly connected to form a sealed cavity.

According to the electromagnetic structure of the direct-current relay, the arc extinguishing cover is provided with the side wall which can realize electrical isolation between the external magnetic steel and the static contact.

In the prior art, the direct current relay generally adopts a mode of a group of magnetic steels for magnetic quenching, the magnetic induction intensity of the space where the electric arc is positioned is relatively low, and the magnetic induction intensity is greatly improved through the middle magnetic steel; the metal sheet and the upper magnetizer are respectively arranged on the upper sides of the outer magnetic steel and the middle magnetic steel, so that the effect of shielding an external magnetic field is achieved, the interference caused to the outside of the direct current relay is avoided, meanwhile, the internal magnetic field can be enhanced, the magnetic induction intensity in the space where the electric arc is located is further increased, and the problem that the contact is adhered due to electric repulsion force can be reduced by a magnetic conduction loop formed by the upper magnetizer and the lower magnetizer. The utility model discloses a strong magnetism arc extinguishing technique promotes direct current relay's arc extinguishing performance, combines the structure of anti contact adhesion to promote direct current relay's the ability that bears the heavy current of short time on this basis to improve direct current relay's electric life and reliability.

Drawings

Fig. 1 is a front sectional view of the electromagnetic structure of the dc relay;

FIG. 2 is an exploded view of a ceramic component of the electromagnetic structure;

figure 3 is a schematic view of an arc chute structure in the electromagnetic structure;

FIG. 4 is a schematic diagram of a kinematic mechanism in the electromagnetic structure;

FIG. 5 is a schematic diagram of a magnetic steel structure in the electromagnetic structure;

fig. 6 is a schematic diagram of electromagnetic attraction in the electromagnetic structure.

Detailed Description

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

As shown in fig. 1-6: the utility model discloses a realize like this, a direct current relay's electromagnetic structure, including metal sleeve 1 and ceramic subassembly 2, metal sleeve 1 and ceramic subassembly 2 combine closely to constitute airtight space.

The ceramic component 2 is formed by welding a fixed contact 21, a ceramic body 22 and a kovar piece 23 together, an arc extinguishing cover 3 is arranged below the ceramic body 22, the lower portion of the fixed contact 21 penetrates through a round hole 31 of the arc extinguishing cover 3, a groove 32 is formed in the middle of the arc extinguishing cover 3, a middle magnetic steel 5 is embedded in the groove 32, an upper magnetizer 6 is arranged outside the middle magnetic steel 5, the upper magnetizer 6 is of a U-shaped structure, the top plane of the magnetizer 6 is arranged between the ceramic body 22 and the middle magnetic steel 5, bent walls at two ends of the magnetizer penetrate into a square groove 33 of the arc extinguishing cover 3, a rubber ring 7 is arranged in an annular sealing groove 34 of the arc extinguishing cover 3, and the rubber ring 7, the arc extinguishing cover 3 and the ceramic body 22 are in a pressing state to electrically isolate the upper magnetizer 6 from the fixed contact 21 and realize mechanical buffering between the arc extinguishing cover 3 and the ceramic body 22.

A group of external magnetic steels 4 are arranged outside the arc extinguishing chamber 3, the external magnetic steels 4 are intersected with an extended line of a connecting line of the two fixed contacts 21, the magnetic field direction is vertical to the current direction flowing through the fixed contacts 21, the magnetic field directions of the opposite surfaces of the external magnetic steels 4 and the middle magnetic steel 5 are opposite, namely the magnetic field directions of the external magnetic steels 4 and the middle magnetic steel 5 are in a mutual attraction state, and metal sheets 8 are arranged between the external magnetic steels 4 and the ceramic body 22 and used for shielding the magnetic fields of the external magnetic steels 4 and reducing the interference of the magnetic fields of the external magnetic steels 4 to the outside.

A moving mechanism 9 is arranged below the two fixed contacts 21, the moving mechanism 9 can reciprocate relative to the fixed contacts 21, in the moving mechanism 9, a shaft 96 sequentially passes through a push rod 94, a moving contact 91, a lower magnetizer 92, a contact spring 95, an iron core spring 97 and a moving iron core 98, and clamp springs 93 are arranged at two ends of the shaft 96 to limit the push rod 94 and the moving iron core 98 respectively.

When the moving iron core 98 overcomes the counterforce of the iron core spring 97 to move towards the direction of the static contact 21 under the action of external force (such as electromagnetic force), the moving contact 91 and the lower magnetizer 92 synchronously move towards the direction of the static contact 21, when the moving contact 91 moves to be contacted with the static contact 21, the static contact 21 starts to be subjected to the counterforce of the contact spring 95, when the moving iron core 98 continues to move until the maximum displacement (namely the contact spring reaches the maximum compression), the moving iron core 98 stops moving, the static contact 21 and the moving contact 91 are in close contact under the action of the contact spring 95, and at the moment, the two static contacts 21 and the moving contact 91 form a conductive loop;

when the external force of the moving iron core 98 is weakened or disappears, under the action of the contact spring 95 and the iron core spring 97, the moving mechanism 9 moves towards the direction away from the static contact 21, the moving contact 91 is separated from the static contact 21, and the circuit between the two static contacts 21 is disconnected.

Because the two static contacts 21 are conducted by direct current with high voltage and large current, electric arcs can be generated at the moment of contact and separation of the static contacts 21 and the movable contacts 91, and if the electric arcs cannot be extinguished as soon as possible, the direct current relay can be burnt;

if short-circuit current occurs in the conductive loop, huo Mli between the static contact 21 and the movable contact 91 is increased, that is, the electric repulsion between the static contact 21 and the movable contact 91 is increased, which easily causes the pressure reduction and even mutual repulsion between the static contact and the movable contact, when the pressure of the contact is reduced, the contact resistance between the static contact and the movable contact is increased, the temperature rise is increased, the static contact and the movable contact are adhered due to high temperature, when the movable contact and the static contact are mutually repelled, the generated electric arc ablates the materials on the surfaces of the static contact and the movable contact to a molten state, and the adhesion of the contacts can also be caused.

In the patent, because the middle magnetic steel 5 is added at the middle position of the group of external magnetic steels 4, the magnetic induction intensity in the magnetic field space where each static contact 21 is located is greatly improved, electric arcs between the static contact 21 and the movable contact 91 can be quickly blown away, and the extinguishing speed of the electric arcs is accelerated; the upper magnetizer 6 is a magnetic conductive metal part, the middle magnetic steel 5 is partially surrounded to shield the interference of the middle magnetic steel 5 to the outside, the upper magnetizer 6 and the lower magnetizer 92 are surrounded around the movable contact 91, when the movable contact 91 conducts short-circuit current, the magnetic field intensity around the movable contact is increased, the suction force between the upper magnetizer 6 and the lower magnetizer 92 is increased, the pressure between the movable contact 91 and the static contact 21 is increased when the lower magnetizer 92 is subjected to the suction force towards the direction of the upper magnetizer 6, and therefore the phenomenon that the contact resistance between the static contact 21 and the movable contact 91 is increased or the contacts are repelled due to electric repulsion is prevented.

Claims (8)

1. An electromagnetic structure of a direct current relay comprises a ceramic component and a metal sleeve, wherein the ceramic component at least comprises a fixed contact, a ceramic body and a kovar piece, an arc extinguishing cover is arranged below the ceramic body, a reciprocating motion mechanism is arranged below the fixed contact, and an external magnet steel is arranged outside the arc extinguishing cover.

2. The electromagnetic structure of a dc relay as claimed in claim 1, wherein in said moving mechanism, a shaft passes through the push rod, the moving contact, the lower magnetizer, the contact spring, the core spring and the moving core in sequence, and two ends of the shaft are provided with clamp springs for respectively limiting the push rod and the moving core.

3. The electromagnetic structure of a dc relay according to claim 2, wherein said upper and lower magnetic conductors are U-shaped and form a magnetic conductive loop around said movable contact.

4. The electromagnetic structure of a direct current relay according to claim 3, characterized in that a square groove is provided in the middle of the arc-extinguishing chamber, the middle magnetic steel is placed in the square groove, and the U-shaped upper magnetizer surrounds the top surface and two side surfaces of the middle magnetic steel.

5. The electromagnetic structure of a dc relay according to claim 1, wherein a metal sheet is disposed on said external magnet, said metal sheet being a magnetic conductive material for shielding a magnetic field of said external magnet.

6. The electromagnetic structure of a dc relay according to claim 1, wherein a rubber ring is disposed between the arc-extinguishing chamber and the ceramic body for electrically isolating the upper magnetic conductor from the stationary contact.

7. The electromagnetic structure of a dc relay according to claim 1, wherein the ceramic member is tightly connected to the metal sleeve to form a sealed chamber.

8. The electromagnetic structure of a dc relay according to claim 1, wherein said arc-extinguishing chamber has a side wall for electrically isolating the external magnetic steel from the stationary contact.

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