Attachment of electrical contacts to associated blades

摘要

A switch blade or plate (10) is prepared to receive an associated contact point (46) by embossing its top surface. This operation results in a projection of blade material underneath. The contact point is pre-formed by an agglomerated block of alloy powder, possibly fused together before fitting. It is pressed into the embossed recess to be lightly retained. Welding into place is accomplished by a machine whose upper electrode is recessed to form a die, its lower electrode (44) having a matching protuberance (50). This operation flattens the metal projecting beneath and partly refuses the contact ensuring firm attachment to the surrounding material as the two are pressed firmly together.