SU995138A1 - Contact system - Google Patents

Description

The invention relates to electrical engineering, in particular to electrical equipment, and can be used in the manufacture of electrical devices such as contactors, switches, starters, disconnectors, and in other cases.

Contact systems are known, consisting of movable contacts made of special electrocontact materials, mainly made from alloys based on noble metals, in particular, silver L.

The disadvantage of this contact system is that it requires a high consumption of scarce silver. /

Closest to the current offer. The technical entity is a contact system, the mobile and fixed contacts, one of which is made of an alloy based on silver and the other of an alloy on copper 6.

The disadvantage of this contact system is the low mechanical and electrical wear resistance of x-contacts.

The purpose of the invention is to increase the mechanical and electrical wear resistance of contacts.

The goal is achieved by the fact that in the contact system containing movable and fixed contacts, one KOTOi jx is made of an alloy based on copper, and the other of an alloy based on silver, the contact made

10 made of copper based alloy contains a diffusion contact surface of aluminum

In addition, the diffusion

15, the coating on the contact surface may be 0.2-0.7 of the thickness of the contact plate.

Example. The movable contact is made of an alloy system copper-chrome

20 (chrome-plated bronze), with a diffusion coating — aluminum, and the fixed contact is made of cermet of a silver-based alloy. This contact system 25 is used in automatic switches of type A3710 .:;.

KpoMie, for comparison, they make automatic switches, in KOTOiMX both contacts of a pair of contact systems (mobile and stationary) are made of metal-ceramic based on silver. The tests are carried out according to the metric. The rated current at the switches during testing is 1 W.A. The tests of the operation of the switches in continuous mode are carried out for 600 hours. The temperature above the terminals of the external conductors is determined. The temperature values of the excess overpressure of the outer conductor presses in the compared cases are given in the table, Maximum

system of over temperature, s, after 600 hours of operation

45

50 Not more than 65

As can be seen from the table, the proposed contact system practically does not differ from the known system in terms of the main characteristic determining the system performance, while silver consumption for the manufacture of the proposed contact system is halved,

The presence of diffusion aluminum coating by creating a robust formula

Claims (1)

1, A contact system comprising movable and fixed contacts, one of which is made of a silver-based alloy, and the other of a copper-based alloy, characterized in that, in order to increase the mechanical and electrical wear resistance of the contacts, a contact made of an alloy on copper-based, contains a diffusion coating of the contact surface with aluminum. , 2, The system of claim 1, wherein the depth of the diffusion coating on the contact surface is 0.2-0.7 times the thickness of the contact plate. Sources of information taken into account during the examination 1, USSR Author's Certificate, No. 306506, KL, H 01 H 1/02, 1970, 2, Patent of Germany 1640039, CL. 21 C 35/09, 1979. This thick layer on the Contact Surface allows the use of such a contact system under heavy mechanical and shock conditions: loading, t, e. provides resistance to contact and shock of the nose. In addition, this layer contains intermetallic compounds that harden the layer and increase the abrasive resistance of the layer. Finally, the specified layer formed by a diffusion coating contains on the contact surface a separating oxide film, mainly on the basis of aluminum oxide, which prevents sintering of contacts.