1. Field of the Invention
The present invention generally relates to an electrical connector assembly, and more particularly to an electrical connector assembly for removably mounting a chip module, such as a Central Processing Unit (CPU), to a printed circuit board.
2. Description of Related Art
U.S. Pat. No. 6,875,022, issued on Apr. 5, 2005 and U.S. Pat. No. 6,905,353, both assigned to HonHai, disclose an electrical connector assembly for electrically connecting a chip module to a printed circuit board. The electrical connector assembly comprises an insulative housing, a plurality of contacts received in the insulative housing, and a pick-up cap covering an upper surface of the insulative housing. The insulative housing defines a plurality of contact-receiving slots penetrating through upper and lower surfaces thereof. The contacts are received in the contact-receiving slots and have upper and lower contacting surfaces. The insulative housing is displaced on the printed circuit board to form electrical connection between the lower contacting surfaces of the contacts with the printed circuit board. Then the chip module is placed on the upper surface of the insulative housing to form electrical connection with the upper contacting surfaces of the contacts. Thus, the electrical connection between the chip module and the printed circuit board is realized.
The pick-up cap is latchably assembled to the upper surface of the insulative housing. The pick-up cap can be sucked by a vacuum mechanism to realize the movement of the electrical connector and covers the upper surface of the insulative housing to prevent dust from outside or damage made to upper contacting surfaces of the contacts. However, the electrical connector assembly with such structure has the shortcomings as follows: The pick-up cap only covers the upper surface of the insulative housing to protect the upper contacting surfaces of the contacts. The lower contacting surfaces of the contacts are not protected which are prone to be damaged or dusted during the movement of the insulative housing and the contacts.
Therefore, it is desired to provide an improved electrical connector assembly to stress the problems mentioned above.