Patent ID: 7347708

Claim:
A plug comprising: an insulating casing; an insulating seat installed in the insulating casing; the insulating seat having a cubic shape with one opened side; a side opposite to the opened side of the insulating seat having two slots; and a top side of the insulating seat having a recess which is communicated to a hollow central space of the insulating seat; a sliding member or button installed in the recess at the top side of the insulating seat; the sliding member or button protruding from an aperture of the insulating casing; a lower side of the sliding member or button having four supporting pins and an upper surface of the sliding member or button being formed as a teeth surface; a terminal seat installed in the insulating seat; and the terminal seat having two push portions; a female terminal installed on the terminal seat; the female terminal having a first sub-terminal and a second sub-terminal, the first sub-terminal having an arm and two conductive sheets; the two conductive sheets of the first sub-terminal being formed as a clamping portion; one conductive sheet nearer the second sub-terminal being extended with a positioning portion; and a projection being protruded from the positioning portion and being between the positioning portion of the first sub-terminal and the conductive sheet of the first sub-terminal; the second sub-terminal having a structure identical to that of the first sub-terminal, but arranged oppositely to that of the first sub-terminal; wherein when male terminals are inserted into the female terminal; the sliding member or button being pushed so that the supporting pins of the sliding member or button move forwards to push the positioning portions of the terminal seat; and then the projections of the positioning portions will be buckled into round holes of the male terminals and thus the male terminal being fixed; thereby, the male terminal being firmly secured; wherein the positioning portion is an elastic metal sheet; and wherein the positioning portion is installed in a hole of the conductive sheet of the clamping portion near a center of the terminal seat.