Electrical connectors – With coupling movement-actuating means or retaining means in... – Including compound movement of coupling part
Reexamination Certificate
2003-06-09
2004-12-14
Zarroli, Michael C. (Department: 2839)
Electrical connectors
With coupling movement-actuating means or retaining means in...
Including compound movement of coupling part
C439S857000, C439S884000
Reexamination Certificate
active
06830471
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to electrical contacts, and particularly to electrical contacts used in electrical connectors for connecting electronic packages such as pin grid array (PGA) central processing units (CPUs) with circuit substrates such as printed circuit boards (PCBs).
2. Description of the Prior Art
Zero insertion force, low actuation force connectors are widely used for electrically connecting PGA CPUs with PCBs. Usually, these connectors comprise an insulative base and a plurality of contacts received in the base. Examples of such connectors are disclosed in U.S. Pat. No. 6,319,038 and TW Patent Issue No. 472962. Referring to
FIGS. 3 and 4
, each contact
6
comprises a medial portion
60
, a solder portion
62
depending from the medial portion
60
, and a pair of arm portions
61
extending upwardly from the medial portion
60
. The medial portion
60
has a U-shaped horizontal cross-section. The medial portion
60
comprises a pair of sidewalls
600
parallel to each other, and an engaging member
601
below one of the sidewalls
600
. The engaging member
601
has several protrusions, for engaging with an insulative base (not shown) and thereby mounting the contact
6
in the base. The solder portion
62
extends downwardly from a bottom of the engaging member
601
, for electrically connecting with a PCB (not shown). Each arm portion
61
extends upwardly from a top of a respective sidewall
600
, thereby defining a first line
602
at a junction of the sidewall
600
and the arm portion
61
. The arm portions
61
are bent obliquely toward each other, and are each deflectable from a rest position to a deflected position (as depicted with broken lines in
FIG. 4
) by a corresponding horizontally actuatable pin
8
of a CPU. Each arm portion
61
comprises a contact portion
610
at a top end thereof, and guiding portion
611
extending obliquely from an end of the contact portion
610
. The contact portions
610
of the arms
61
are parallel to each other, and define a first distance therebetween. A second line
613
is defined at a bottom edge of each contact portion
610
and its adjacent guiding portion
611
. The guiding portions
611
of the arms
61
extend obliquely away from each other, thereby defining a second maximum distance therebetween. The second distance is greater than the first distance.
Referring particularly to
FIG. 4
, in use, the pin
8
is inserted into a space between the free ends of the guiding portions
611
. The second distance is greater than a diameter of the pin
8
. Accordingly, the pin
8
is inserted with zero insertion force as between the contact
6
and the pin
8
, and each arm portion
61
remains in the rest position. Then the pin
8
is moved horizontally toward the contact portions
610
. Opposite side portions of a leading periphery of the pin
8
eventually contact insides of the guiding portions
611
, whereupon an actuation force is applied to drive the pin
8
further. Finally, the pin
8
is received between the contact portions
610
. During driving of the pin
8
, a desired radius of leverage corresponding to the actuation force is represented by distance ‘b’. However, in fact, as can be seen from the broken lines of
FIG. 4
, when the pin
8
contacts the insides of the guiding portions
611
, the arm portions
61
deflect outwardly with respect to the first lines
602
toward respective deflected positions. The pin
8
contacts a contact point of each guiding portion
611
which is located on the second line
613
, and the radius of leverage corresponding to the actuation force is in fact distance ‘b prime’ (‘b’). Thus, the actuation force required to drive the pin
8
into the contact
6
is greater than desired.
In view of the above, a new electrical contact that overcomes the above-mentioned disadvantages is desired.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an electrical contact used in an electrical connector, whereby friction between the contact and a corresponding mating pin is minimized.
Another object of the present invention is to provide an electrical contact used in an electrical connector, whereby minimal actuation force is required to drive a corresponding mating pin into engagement with the contact.
To achieve the above-mentioned objects, an electrical contact in accordance with a preferred embodiment of the present invention is used in an electrical connector. The contact is for engaging with a corresponding horizontally actuatable pin of a CPU. The contact comprises a medial portion, a pair of arm portions extending from a top of the medial portion, and a solder portion depending from a bottom of the medial portion. The medial portion comprises an engaging portion for engaging with an insulative base of the connector. The solder portion depends from a bottom of the engaging portion, for engaging with a PCB. Each arm portion is deflectable from a rest position to a deflected position by the pin. Each arm portion comprises a contact portion at a top end thereof, and a guiding portion extending obliquely from an end of the contact portion. The guiding portion comprises an inner convex side and a bottom edge. The contact portion also has an inner convex side. As each arm portion is deflected from the rest position to the deflected position, the pin contacts a contact section of the arm portion, the contact section being located above the bottom edge.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which:
REFERENCES:
patent: 5092789 (1992-03-01), Sinclair
patent: 5797774 (1998-08-01), Kaneko
patent: 6267615 (2001-07-01), Lin
patent: 6319038 (2001-11-01), Howell et al.
patent: 6450826 (2002-09-01), Howell et al.
patent: 6461183 (2002-10-01), Ohkita et al.
patent: 6478637 (2002-11-01), Ohkita et al.
patent: 6537095 (2003-03-01), Azuma
patent: 6558182 (2003-05-01), Ohkita et al.
patent: 6565368 (2003-05-01), Liao et al.
patent: 6638119 (2003-10-01), Chang
patent: 6692265 (2004-02-01), Kung et al.
Hsu Hsiu-Yuan
Okita Masao
Chung Wei Te
Hon Hai - Precision Ind. Co., Ltd.
Zarroli Michael C.
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