CN111564339B

CN111564339B - Miniature sealed electromagnetic relay bottom plate underlying arc extinguishing structure

Info

Publication number: CN111564339B
Application number: CN202010569074.2A
Authority: CN
Inventors: 李博; 梁慧敏; 张家赫; 富嘉城; 谭旭
Original assignee: Harbin Institute of Technology
Current assignee: Harbin Institute of Technology
Priority date: 2020-06-19
Filing date: 2020-06-19
Publication date: 2022-06-10
Anticipated expiration: 2040-06-19
Also published as: CN111564339A

Abstract

Miniature sealed electromagnetic relay bottom plate underlying arc extinguishing structure belongs to electromagnetic relay technical field. The invention relates to a bottom plate underneath type arc extinguishing structure of a small-sized sealed electromagnetic relay, which comprises a permanent magnet and a contact spring group; the contact spring group is vertically arranged on the upper surface of the bottom plate of the electromagnetic relay; the permanent magnet is embedded into the elongated slot and fixed by glue joint, the upper surface of the permanent magnet is flush with the upper surface of the bottom plate, the contact spring group is arranged on the upper surface of the permanent magnet, the permanent magnetic field of the permanent magnet is vertical to the contact gap of the contact spring group, and the extension directions of the sheet ends of the contact spring group are the same or opposite. The invention makes the electric arc generated between the contacts be elongated under the action of the magnetic field when the electromagnetic relay acts, thereby being quickly extinguished, reducing the damage of the electric arc ablation to the surfaces of the contacts, simultaneously being beneficial to quickly diffusing the heat of the electric arc, reducing the influence of the heat generated by continuous arc burning on an electromagnetic system, and improving the service life of the relay and the overload resistance.

Description

Miniature sealed electromagnetic relay bottom plate underlying arc extinguishing structure

Technical Field

The invention belongs to the technical field of electromagnetic relays, and particularly relates to a bottom plate underneath type arc extinguishing structure of a small sealed electromagnetic relay.

Background

The small-sized sealed electromagnetic relay is widely applied to the fields of aviation, aerospace, communication and the like, and plays key roles of signal transmission, loop switching and the like. In a small-sized sealed electromagnetic relay, contact bonding is the most common fault mode, and due to the fact that the internal space of the relay is small, an arc extinguishing device is difficult to set, a contact system can generate violent electric arcs in work, particularly in a state of frequent on-off of a large carrier frequency, contact ablation and even fusion welding are easily caused, and contact reliability of contacts is poor. Meanwhile, the heat flow generated by continuous arcing enables the contact area to have higher temperature, a large amount of heat can be sprayed and diffused to other parts along with the electric arc, the performance of an electromagnetic system is reduced, the suction and release performance of the relay is influenced, and the service life loss of the relay is accelerated.

The invention patent application with publication number CN109950095A discloses "an arc extinguishing structure for relay and manufacturing method thereof", in which the reed form must be the extending direction of the sheet end outward, and only under this reed structure can the permanent magnet arc extinguishing structure described in the invention application be implemented.

Disclosure of Invention

The invention aims to provide a bottom plate underneath type arc extinguishing structure of a small sealed electromagnetic relay, which effectively reduces the influence of arc on the performance of a contact system of the electromagnetic relay, improves the on-load operation capacity of the electromagnetic relay and prolongs the service life of the electromagnetic relay through the design of the bottom plate underneath type arc extinguishing structure.

According to the underneath type arc extinguishing structure of the bottom plate of the small-sized sealed electromagnetic relay, the bottom plate of the electromagnetic relay is provided with the long groove, the permanent magnet is fixed in the long groove and is positioned below the contact spring group, the permanent magnet is made of neodymium iron boron with strong magnetism, and a permanent magnetic field generated by the permanent magnet is perpendicular to a contact gap after magnetization and magnetic stabilization treatment before being installed in the long groove; this structural design has realized carrying out effective arc extinguishing in small-size sealed electromagnetic relay's less space, utilizes the magnetic field that the permanent magnet produced, makes the electric arc that produces between the contact elongated under the effect of lorentz force, until going out. Compared with the prior art, the bottom plate underlying arc extinguishing structure of the small-sized sealed electromagnetic relay can realize magnetic field arc extinguishing in a narrow space, quickly eliminate electric arcs generated during reed action, reduce ablation of the electric arcs on the surfaces of contacts, simultaneously reduce heat released by continuous arc burning, reduce damage of the heat to an electromagnetic system in the action process of the relay, and improve the service life and the overload resistance of the relay.

In order to solve the technical problems, the invention adopts the technical scheme that:

the miniature sealed electromagnetic relay bottom plate underneath type arc extinguishing structure comprises a permanent magnet and a contact spring group; the contact spring group is vertically arranged on the upper surface of a bottom plate of the electromagnetic relay; the contact spring group is arranged on the upper surface of the permanent magnet, the permanent magnetic field of the permanent magnet is perpendicular to the contact gap of the contact spring group, and the extension directions of the sheet ends of the contact spring group are the same or opposite.

Compared with the prior art, the invention has the beneficial effects that:

the bottom plate underlying arc extinguishing structure of the small-sized sealed electromagnetic relay can be provided with the permanent magnet arc extinguishing structure on the premise of not compressing the design space of the contact spring group, can rapidly eliminate electric arcs generated when the movable spring leaf and the movable and static spring leaves act in the switching-on and switching-off process, reduces the ablation of the electric arcs on the contact surface, reduces the heat released by the electric arcs, reduces the damage of the heat to an electromagnetic system in the acting process of the electromagnetic relay, prolongs the service life of the electromagnetic relay, improves the overload resistance of the electromagnetic relay, and simultaneously keeps the mechanical resistance of the original electromagnetic relay to the maximum extent.

In the invention, because the permanent magnet is embedded in the bottom plate, the extension directions of all the sheet ends of the spring plates are inward or outward, and the installation of the arc extinguishing permanent magnet is not influenced, so that the arrangement mode of the arc extinguishing permanent magnet is greatly different from that of the invention patent application listed in the background technology.

Drawings

FIG. 1 is a schematic diagram of a bottom plate underneath type arc extinguishing structure of a small-sized sealed electromagnetic relay according to the present invention;

FIG. 2 is a schematic view of the bottom plate slotting;

fig. 3 is a blowing schematic diagram of the miniature sealed electromagnetic relay bottom plate underneath type arc extinguishing structure.

The names and reference numbers of the components referred to in the above figures are as follows:

the spring comprises a static spring a, a dynamic static spring b, a permanent magnet c, a bottom plate d and a dynamic spring e.

Detailed Description

The first embodiment is as follows: as shown in fig. 1 and fig. 2, the present embodiment discloses a bottom plate underneath type arc extinguishing structure of a small-sized sealed electromagnetic relay, which includes a permanent magnet c and a contact spring group; the contact spring group is vertically arranged on the upper surface of a bottom plate d of the electromagnetic relay, the curled end of the contact spring group is welded and fixed on the leading-out rod, and the leading-out rod and the glass insulator are sintered and fixed on the bottom plate d together; the contact spring group is arranged on the upper surface of the permanent magnet c, a permanent magnetic field of the permanent magnet c is perpendicular to a contact gap of the contact spring group, and the extension directions of sheet ends of the contact spring group are the same or opposite.

Further, as shown in fig. 1 and 3, the permanent magnet c is a rectangular parallelepiped and made of an ndfeb material (it is ensured that a relatively large magnetic field is generated at the position where the arc is generated with a relatively small volume, and demagnetization of the permanent magnet at a high temperature generated by the arc can be avoided).

Further, as shown in fig. 1 and 3, the side edges of the permanent magnet c are rounded (to facilitate the installation of the permanent magnet c).

Further, as shown in fig. 1 and 3, the contact spring set includes a static spring piece a, a dynamic static spring piece b and a dynamic spring piece e; the permanent magnetic contact device is characterized in that the static spring piece a, the movable static spring piece b and the movable spring piece e are all vertically arranged, the extension directions of the sheet ends of the static spring piece a and the movable static spring piece b are opposite and are all arranged on the upper surface of the permanent magnet c, a gap is formed between the sheet ends of the static spring piece a and the movable static spring piece b, the movable spring piece e is arranged between the static spring piece a and the movable static spring piece b, and the permanent magnetic field of the permanent magnet c is perpendicular to the gap (namely the contact gap) between the static spring piece a and the movable static spring piece b.

As shown in fig. 3, when the movable spring e and the fixed spring a are separated or the movable spring e and the movable stationary spring b are separated during arc blowing, an arc is generated therebetween under a load, and the arc is perpendicular to a magnetic field generated by the permanent magnet c embedded in the long groove of the base plate, so that the arc is elongated by the lorentz force until the arc is extinguished.

The design method of the bottom plate underlying arc extinguishing structure of the small-sized sealed electromagnetic relay comprises the following specific steps:

the method comprises the following steps: manufacturing a permanent magnet c, wherein the whole shape of the permanent magnet c is a cuboid, the side edges of the permanent magnet c are rounded, the installation of the permanent magnet c is convenient, the specific size of the permanent magnet c is determined according to the space of an electromagnetic relay, the installation of the permanent magnet c is ensured not to influence the action of a movable reed e and a movable static reed b, the permanent magnet c adopts neodymium iron boron as a manufacturing material, and the permanent magnet c is magnetized and stabilized;

step two: a thickened bottom plate d with the thickness 1.5 times that of the conventional bottom plate is adopted, so that the permanent magnet c is conveniently mounted on the bottom plate d, and the mechanical property of the bottom plate d is ensured; the conventional base plate is typically 1.5mm thick;

step three: the upper surface of the bottom plate d is provided with a long groove, the long groove is positioned right below the contact spring group, and the size of the long groove is matched with that of the permanent magnet c; embedding the permanent magnet c into the elongated slot on the bottom plate d, and fixing by using AB glue to ensure that the direction of a magnetic field generated by the permanent magnet c in an air gap area is vertical to a contact gap;

step four: the installation contact spring group comprises a static spring leaf a, a dynamic static spring leaf b and a dynamic spring leaf e, the curled ends of the static spring leaf a, the dynamic static spring leaf b and the dynamic spring leaf e are welded and fixed on corresponding leading-out rods, and the leading-out rods and the glass insulator are sintered and fixed on a bottom plate d together; vertically arranging the three reeds on the upper surfaces of the bottom plate d and the permanent magnet c;

step five: and assembling other components of the electromagnetic relay.

The foregoing description is intended to be illustrative rather than limiting, and it will be appreciated by those skilled in the art that many modifications, variations or equivalents may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. An arc extinguishing structure with a bottom plate underneath for a small sealed electromagnetic relay comprises a permanent magnet (c) and a contact spring group; the contact spring group is vertically arranged on the upper surface of a bottom plate (d) of the electromagnetic relay; the method is characterized in that: an elongated slot is formed in one end of the upper surface of the bottom plate (d), the permanent magnet (c) is embedded into the elongated slot and fixed by glue joint, the upper surface of the permanent magnet (c) is flush with the upper surface of the bottom plate (d), the contact spring group is arranged on the upper surface of the permanent magnet (c), the permanent magnetic field of the permanent magnet (c) is perpendicular to the contact gap of the contact spring group, and the extension directions of the sheet ends of the contact spring group are opposite;

the permanent magnet (c) is a cuboid and is made of a neodymium iron boron material; the contact spring group comprises a static spring piece (a), a movable static spring piece (b) and a movable spring piece (e); the permanent magnetic field of the permanent magnet (c) is perpendicular to the gap between the static reed (a) and the movable static reed (b).

2. The under-chassis type arc extinguishing structure for the small-sized sealed electromagnetic relay according to claim 1, wherein: the side edges of the permanent magnets (c) are provided with rounding.