Contact mechanism of direct-current relay

Abstract

The utility model relates to a relay, in particular to a contact of a direct-current relay. A contact mechanism of a direct-current relay is characterized in that a moving contact assembly is arranged in an arc extinguish chamber space formed by a static contact assembly and a magnet yoke, a push rod of the moving contact assembly penetrates through the magnet yoke and is in threaded connection with a moving iron core, an iron core spring is sleeved outside the push rod, and two ends of the iron core spring are respectively contacted with the magnet yoke and the moving iron core; in the moving contact assembly, a magnetic conductive sheet assembly and a push rod assembly are fixedly connected, a moving contact, a lower magnetic conductive sheet and a contact spring are sequentially arranged in the magnetic conductive sheet assembly and the push rod assembly, the magnetic conductive sheet assembly comprises an upper magnetic conductive sheet and a U-shaped support, the U-shaped support is provided with two groups of bending walls, and the bending walls are arranged on the upper magnetic conductive sheet. And after the two groups of bent walls are unfolded, the upper magnetic conductive sheet is fixed in the U-shaped recess. According to the utility model, the influence of loose contact between the moving contact and the static contact caused by electric repulsive force is reduced, and the problem of adhesion caused by overheating of the contacts is avoided.

Description

TECHNICAL FIELD

[0001] The utility model relates to a relay, especially a contact of a direct current relay. BACKGROUND

[0002] The direct current relay is a kind of switching device for remote control of circuit, with the vigorous development of new energy industry, the application of direct current relay in electric vehicle, charging pile and energy storage equipment has been more and more common, direct current relay adopts electromagnetic system consisting of coil and core as control and execution component, to drive the mechanism movement inside relay, make movable contact and static contact connect or disconnect and realize switching function, however, overcurrent or even short-circuit current situation inevitably appears in direct current equipment, under the condition of such large current, movable contact and static contact of direct current relay will produce contact loose or repulsion phenomenon under the action of electric repulsion, lead to the problem of high temperature damage or even burning of direct current relay.

[0003] In prior art, direct current relay usually adopts sealing structure, fills nitrogen or hydrogen gas medium in arc extinguishing chamber, slows down the speed of contact resistance between movable contact and static contact by preventing contact oxidation. The upper part of movable contact assembly is located in the arc extinguishing chamber space formed by static contact assembly and magnetic yoke, the movable contact assembly is a reciprocating mechanism, realizes the contact or separation of movable contact and a pair of static contact, makes the circuit between the two static contacts conduct or disconnect, when the circuit between the two static contacts is conducted, moving iron core and magnetic yoke abut, iron core spring and contact spring are in compression state, static contact and movable contact keep relatively close closure under the pressure of contact spring, ensure that the circuit between the two static contacts is reliably connected, when the movable contact and static contact are closed, current line produces strong contraction near actual contact point, generates repulsive force between contacts, the size of force is proportional to the square of current, therefore, when the current in circuit is very large or short-circuit current appears, movable contact and static contact between the two may lead to contact loose phenomenon due to the existence of electric repulsion, contact resistance between contacts will increase and lead to severe heating of contact part, and the contact may be melted and adhered due to overheating. SUMMARY

[0004] The utility model discloses a contact mechanism of direct current relay, which solves the above problems in the prior art.

[0005] The utility model discloses a contact mechanism of DC relay, which is characterized in that the contact mechanism comprises a static contact assembly, a magnetic yoke, a movable contact assembly, a push rod, a magnetic sheet assembly, a push rod assembly, a movable contact, a lower magnetic sheet, a contact spring, an upper magnetic sheet and a U-shaped support.

[0006] The contact mechanism of DC relay further comprises a convex part on the upper magnetic sheet, and the convex part is in contact with the U-shaped support.

[0007] The contact mechanism of DC relay further comprises a push rod assembly, which comprises a plastic part, a metal gasket and a push rod.

[0008] The contact mechanism of DC relay further comprises that the metal gasket is inserted into the square hole of the U-shaped support and is riveted, so that the magnetic sheet assembly and the push rod assembly are fixed.

[0009] The contact mechanism of DC relay further comprises that the static contact assembly is composed of a pair of static contacts, an arc extinguishing cover and a Kovar ring, the static contact passes through the arc extinguishing cover made of insulating material and is closely connected with the arc extinguishing cover.

[0010] The contact mechanism of DC relay further comprises that the upper magnetic sheet and the lower magnetic sheet are made of magnetic metal material, and the lower magnetic sheet is a U-shaped structure to surround the movable contact.

[0011] The utility model discloses a movable contact is provided with magnetic sheet assembly in the upper portion, and the lower portion has the U-shaped lower magnetic sheet, and the upper magnetic sheet in the magnetic sheet assembly is fixed by the U-shaped support, the U-shaped support is rigidly connected with the push rod assembly by metal material, when the movable contact and the two static contacts are closed and electrified, the magnetic field is generated around the movable contact, the lower magnetic sheet is forced to the movable contact under the action of Lorentz force, the contact pressure between the movable contact and the static contact is increased, the influence of the movable contact and the static contact that the electric repulsion force causes the contact loose is reduced, and the problem of contact overheating and adhesion is avoided. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is the sectional view of the utility model;

[0013] Figure 2 It is the movable contact assembly assembly drawing;

[0014] Figure 3 is the structure diagram of the moving contact assembly;

[0015] Figure 4 is the assembly diagram of the magnetic conducting sheet assembly;

[0016] Figure 5 is the structure diagram of the magnetic conducting sheet assembly;

[0017] Figure 6 is the structure diagram of the push rod assembly;

[0018] Figure 7 is the structure diagram of the stationary contact assembly;

[0019] Figure 8 is the magnetic line and current diagram of the moving contact assembly. DETAILED DESCRIPTION

[0020] Referring to Figures 1-4 A contact mechanism of a DC relay, comprising a stationary contact assembly 1, a magnetic yoke 2, a moving contact assembly 3, a core spring 4 and a moving core 5, wherein the stationary contact assembly is composed of a pair of stationary contacts 11, an arc extinguishing cover 12 and a Kovar ring 13, the stationary contacts 11 pass through the arc extinguishing cover 12 made of insulating material and are tightly connected with the arc extinguishing cover, the lower end of the Kovar ring 13 is in contact with the magnetic yoke 2, the stationary contact assembly 1 and the magnetic yoke 2 jointly constitute an arc extinguishing chamber space, the moving contact assembly 3 is arranged in the arc extinguishing chamber space, the moving contact assembly 3 comprises a magnetic conducting sheet assembly 31, a moving contact 32, a lower magnetic conducting sheet 33, a contact spring 34 and a push rod assembly 35, the magnetic conducting sheet assembly 31 is composed of an upper magnetic conducting sheet 311 and a U-shaped bracket 312, two sets of bent walls 3121 are arranged on the U-shaped bracket 312, after the upper magnetic conducting sheet 311 is placed into the U-shaped bracket 312, the two sets of bent walls 3121 are stretched and abut against the protruding features 3111 of the upper magnetic conducting sheet 311, so that the upper magnetic conducting sheet is fixed in the U-shaped bracket to constitute the magnetic conducting sheet assembly 31, the push rod assembly 35 is integrally formed by a plastic part 351, a metal gasket 352 and a push rod 353, the outer end of the metal gasket 352 in the push rod assembly 35 is inserted into a square hole 3122 of the U-shaped bracket 312, so that the push rod assembly 35 is fixedly connected with the magnetic conducting sheet assembly 31, the contact spring 34 is placed on the push rod assembly 35 and is in contact with the metal gasket 352, the lower magnetic conducting sheet 33 and the moving contact 32 are sequentially arranged above the contact spring, the lower end of the push rod 353 in the moving contact assembly 3 passes through the magnetic yoke 2 and is threadedly connected with the moving core 5, the core spring 4 is sleeved on the outside of the push rod 353, and the two ends of the core spring are in contact with the magnetic yoke 2 and the moving core 5 respectively.

[0021] The utility model discloses a movable contact 32 and two static contacts 11 close and energize, because the magnetic field is produced around movable contact, and the force of the lower magnetic conductive sheet 33 is produced to movable contact 32 under the action of Lorentz force, make the contact pressure between movable contact 32 and static contact 11 increase, alleviate the influence that the electric repulsion leads to the contact loose between movable contact and static contact, avoid the problem of contact overheating and sticking together.

Claims

1. A contact mechanism for a DC relay, comprising a moving contact assembly within an arc-extinguishing chamber formed by a stationary contact assembly and a magnetic yoke; a push rod of the moving contact assembly passing through the magnetic yoke and threadedly connected to a moving iron core; a core spring sleeved on the push rod, the two ends of the core spring contacting the magnetic yoke and the moving iron core respectively; in the moving contact assembly, a magnetic conductive sheet assembly and a push rod assembly are fixedly connected; a moving contact, a lower magnetic conductive sheet, and a contact spring are sequentially arranged in the magnetic conductive sheet assembly and the push rod assembly, characterized in that... The magnetic conducting sheet assembly comprises an upper magnetic conducting sheet and a U-shaped support, and two sets of bent walls are arranged on the U-shaped support, which are unfolded to fix the upper magnetic conducting sheet in the recess of the U-shaped support.

2. A contact mechanism for a DC relay as defined in claim 1, characterized in that The upper magnetic conducting sheet is provided with a protrusion, and the bent walls of the U-shaped support are unfolded to abut against the protrusion of the upper magnetic conducting sheet.

3. The contact mechanism of a DC relay as defined in claim 1, wherein The push rod assembly comprises a plastic part, a metal gasket and a push rod, which are formed into an integral part by injection molding.

4. A contact mechanism for a DC relay as defined in claim 3, characterized in that The two ends of the metal gasket are inserted into the square holes of the U-shaped support and are riveted, so that the magnetic conducting sheet assembly and the push rod assembly are fixed.

5. The contact mechanism of a DC relay as defined in claim 1, wherein The static contact assembly is composed of a pair of static contacts, an arc extinguishing cover and a Kovar ring, the static contacts pass through the arc extinguishing cover made of insulating material and are closely connected with the arc extinguishing cover.

6. The contact mechanism of a DC relay as defined in claim 1, wherein The upper magnetic conducting sheet and the lower magnetic conducting sheet are made of magnetic conducting metal material, and the lower magnetic conducting sheet is in U-shaped structure to surround the moving contact.

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