Electrical connector with improved EMI structure

Claim 1

An electrical connector, comprising: an insulative housing having a base portion and a contracted mating tongue extending from the base portion, the base portion defining a mounting face from which a receiving cavity is recessed, a plurality of first and second passageways being defined on opposite sides of the mating tongue and in communication with the receiving cavity; a first contact module having a first insulator and a plurality of first contacts fixed to the first insulator, each first contact comprising a first stiff contacting section cantileveredly extending beyond the first insulator; a second contact module having a second insulator and a plurality of second contacts fixed to the second insulator, each second contact comprising a second stiff contacting section cantileveredly extending beyond the second insulator, under a condition that the first and the second contact modules are jointly received in the receiving cavity with the first and the second contacting sections accommodated in the first and the second passageways, respectively; a first metal shell comprising a plurality of peripheral walls and a mating opening formed by the peripheral walls, the first metal shell being fixed to the insulative housing with the mating tongue residing in the mating opening; and a grounding piece comprising a plurality of side walls and a receiving opening enclosed by the side walls, the grounding piece enclosing the first metal shell with the peripheral walls extending through the receiving opening, wherein the side walls comprise a plurality of half-spherical embosses stamped therefrom to abut against the front metal shell; wherein the side walls of the grounding piece comprise a first side wall, a second side wall opposite to the first side wall and a pair of third and fourth side walls connecting the first and the second side walls, the embosses being formed on each side wall; wherein the grounding piece comprises a retention tab bending from an inner edge of the first side wall under a condition that the retention tab is in communication with the receiving opening and is perpendicular to the first side wall for being fixed in a slot which is defined in the base portion of the insulative housing; wherein a tube-shaped second metal shell enclosing the base portion of the insulative housing to directly engage with the grounding piece; and wherein the grounding piece comprises a pair of bending sections extending from and perpendicular to the third and the fourth side walls, respectively, each bending section being stamped outwardly to form an inclined block engaging with inner surfaces of the second metal shell.