Circuit breaker with movable contacts under insulating gas - has one contact member with galvanically deposited hard silver@ layer

摘要

The sections of the coacting movable contacts (1-3) have a coating (4,6) of silver contg. contact material. One contact (1) has a galvanically deposited hard silver layer (6), while the other contact (2, 3) has a normal silver layer also galvanically deposited. The contact with the hard silver layer pref. serves as a stationary contact. A metal layer of the platinum group, typically of palladium, may be galvanically deposited on the hard silver layer. The latter may be coated by a layer of precious metal and carbon particles, i.e. a graphite-precious metal mixt. ADVANTAGE - Simple wear protection, without complicated, expensive mfg. steps.