US Patent 7815440 Electrical contact with interlocking arrangement

An electrical contact comprises an upper contact pin, a lower contact pin and a spring enveloping between the upper contact pin and the lower contact pin. The upper contact pin has an upper contacting portion and a guiding portion, and the lower contact pin is coupled to the upper contact pin and has a lower contacting portion and a main portion extending from the contacting portion. The main portion of the lower contact pin includes two elastic arms, and each elastic arm has a first and a second locking protrusions engaging with a slot defined on the guiding portion of the upper contact pin respectively to reliably connect the upper contact pin and the lower contact pin.