Electrical connector having improved shielding means

1. An electrical connector comprising:

a housing unit, comprising a shielding member extending in a longitudinal direction and an insulating member retained on the shielding member, the shielding member defining an upper end and a lower end opposite to each other in a vertical direction perpendicular to the longitudinal direction, the insulating member comprising a first portion and a second portion seated on the upper and lower ends respectively and defining a cavity therebetween; and

a contact unit received in the housing unit, the contact unit comprising a plurality of contacts arranged in a row, a metal plate extending horizontally in the longitudinal direction and an insulating body retaining the contacts and the metal plate; wherein

the metal plate divides the cavity into a first cavity and a second cavity in the vertical direction, the contact comprises a first arm above the metal plate received in the first cavity and a second arm under the metal plate received in the second cavity.

2. The electrical connector as claimed in claim 1 , wherein the dielectric constant of the insulating body is less than that of the insulating member.

3. The electrical connector as claimed in claim 2 , wherein the insulating body is made from polyetherimide (PEI) while the insulating member is made from liquid crystal polymer (LCP).

4. The electrical connector as claimed in claim 1 , wherein the dielectric constant of the insulating body is less than 4.

5. The electrical connector as claimed in claim 1 , wherein the shielding member comprises a plurality of recesses between the first and second portions, the insulating body is assembled and retained into the recesses.

6. The electrical connector as claimed in claim 5 , wherein the shielding member comprises a first plate and a plurality of second plates intersecting the first plate, the recesses are formed on the second plates.

7. The electrical connector as claimed in claim 1 , wherein the first cavity and the second cavity are axial symmetrical along the metal plate.

8. The electrical connector as claimed in claim 7 , wherein the contact is axial symmetrical along the metal plate.

9. The electrical connector as claimed in claim 1 , wherein the contacts and the metal plate are insert-molded into the insulating body, the shielding member is insert-molded with the insulating member.

10. An electrical connector for electrically connecting an IC package with a printed circuit board (PCB), comprising:

at least one contact unit, comprising an insulating body and a plurality of contacts retained therein; and

at least one housing unit receiving the contact unit, the housing unit comprising a metallic shielding member extending in a longitudinal direction and an insulating member retaining the shielding member; wherein

the insulating member comprises a first portion and a second portion opposite to each other in a vertical direction perpendicular to the longitudinal direction, the insulating body locates between the first and second portions, both the insulating body and the insulating member are made from plastic, and wherein the dielectric constant of the insulating body is less than that of the insulating member.

11. The electrical connector as claimed in claim 10 , wherein the contact unit comprises a metal plate extending in the longitudinal direction insert-molded into the insulating body.

12. The electrical connector as claimed in claim 11 , wherein the housing unit is substantially axial symmetrical along the metal plate.

13. The electrical connector as claimed in claim 11 , wherein the insulating member comprises a cavity between the first portion and the second portion, the metal plate divides the cavity into two symmetrical cavities in the vertical direction.

14. The electrical connector as claimed in claim 13 , wherein the contact comprises first and second arms extending upwardly and downwardly in the vertical direction running through the cavity and beyond the insulating member for contacting the IC package and the PCB.

15. An electrical connector comprising:

a housing unit including shielding structures in matrix along longitudinal and transverse directions angled to each other to form thereof a plurality of chambers each surrounded by said shielding structures;

a contact unit including a plurality of contacts disposed in the corresponding chambers, respectively, each of said contact defining two opposite contacting ends in a vertical direction perpendicular to both said longitudinal direction and said transverse direction; and

a metallic plate extending along a horizontal plane configurationally defined by said longitudinal direction and said transverse direction, with corresponding through holes to allow said contacts to extend therethrough, without laterally contacting the metallic plate, in the vertical direction so as to divide the corresponding chamber into opposite upper and lower cavities in the vertical direction for reducing EMI (Electro-Magnetic Interference) along the vertical direction; wherein

said metallic plate is equipped with an insulating body integrally formed with both said contacts and the metallic plate via an insert molding process; wherein

said housing unit includes an insulating member integrally formed with the shielding structures via another insert molding process.

16. The electrical connector as claimed in claim 15 , wherein each of said contacts defines a symmetrical configuration, with regard to a horizontal center plane, in said vertical direction, and said horizontal plane is coplanar with said horizontal center plane.

17. The electrical connector as claimed in claim 16 , wherein the metallic plate is mechanically and electrically connected to the shielding structure.

18. The electrical connector as claimed in claim 15 , wherein said insulating body fills the corresponding through holes to laterally isolate the corresponding contacts from the metallic plate.