Direct-current relay

Abstract

The invention discloses a direct-current relay. The direct-current relay comprises a contact portion. The contact portion comprises two static contacts and a movable contact spring, wherein the two static contacts are used for providing current inflowing and outflowing respectively. The two ends of the movable contact spring are matched with the two static contacts respectively. The outer sides of the two ends of the movable contact spring are respectively and symmetrically provided with a steel magnet used for arc blowing, wherein the polarities of the faces, opposite to each other, of the two steel magnets are arranged freely. The outer side of the middle of the movable contact spring is provided with at least one second steel magnet provided with a magnetic field in the preset direction, so that electromagnetic force opposite to contact repulsive force in direction is generated when the magnetic field in the preset direction acts on the movable contact spring. According to the direct-current relay, due to the fact that the steel magnets at the specific positions are arranged on the periphery of the contact portion, the use number of the steel magnets is reduced, the manufacturing cost of the direct-current relay is reduced, and electric arc magnetic blowing force can be increased on the basis that the electromagnetic force is effectively provided for resisting the contact repulsive force; meanwhile, no requirements for the polarities of the steel magnets for arc blowing exist, so that great convenience is brought to assembly and use of the direct-current relay.

Description

technical field [0001] The invention relates to a DC relay, in particular to a DC relay capable of improving the ability of a product to withstand large current. Background technique [0002] The relay is an electronic control device, which has a control system (also known as the input circuit) and a controlled system (also known as the output circuit), usually used in automatic control circuits, it actually uses a smaller current to control a larger An "automatic switch" of electric current. Therefore, it plays the role of automatic adjustment, safety protection, and conversion circuit in the circuit. DC relay is one of the relays. Most of the existing DC relays adopt the scheme of moving reed direct action (also known as solenoid direct action). For example, Hongfa, Tyco, Panasonic, LS and other manufacturers all use screw Wire tube direct-acting scheme, the contact part of this DC relay is as follows figure 1 as shown, figure 1 It is a schematic diagram of the contact...

AI Technical Summary

Problems solved by technology

[0004] 1. The magnetic utilization rate is low. Since there are 6 magnets, the magnetic field between the magnets will be disordered, resulting in a decrease in the strength of the arc-extinguishing magnetic field between the contacts, and the outward force of the arc will be weakened (such as Figure 5 shown), Figure 5 It is a schematic diagram of the magnetic field distribution of the contact bridge with arc-extinguishing magnets. Under the action of the magnetic steel 204 on both sides, an outward force F23 of the arc will be generated, but under the action of the middle magnetic steel 204, an inward force F24 of the arc will be generated ;

[0005] 2. Because 6 pieces of magnetic steel are needed, the cost is very high;

[0006] 3. When a large current flows, the moving spring will generate a disengaged electromagnetic force F25 due to the magnetic steel near the contact (ie, the magnetic steel on both sides) Image 6 , Figure 7 shown), Image 6 is a top view of the contact bridge with arc extinguishing magnets, Figure 7 for along Image 6 The cross-sectional view of the middle B-B line is rotated 90° counterclockwise, thereby weakening the upward electromagnetic force generated by the middle magnetic steel on the moving reed 203, and the effective magnetic energy of the magnetic steel cannot be fully utilized;

[0007] 4. Since the contact bridge with the arc-extinguishing magnet not only has the effect of blowing the arc but also has the effect of making the moving reed resist the contact repulsion, the polarity of the magnetic steel in the contact bridge with the arc-extinguishing magnet And the current direction has strict requirements, which brings inconvenience to the assembly and use of the product

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