The present invention relates generally to an electrical contact, and more particularly to the electrical contact connecting a chip module to a print circuit board.
U.S. Pat. No. 6,824,396 discloses an electrical connector includes an insulative housing and a conductive terminal, the conductive terminal includes a holding portion mounted to the insulative housing, and an upper elastic arm and a lower elastic arm respectively connected to upper and lower ends of the holding portion. The upper and lower elastic arms are respectively connected the chip module and the print circuit board, when the chip module is pressed to the conductive terminal, the conductive terminal connects the chip module and the circuit board to achieve an electrical conduction. Because of the transmitting speed of the high frequency signal of the electrical connector is continuously require improved, however, the upper and lower elastic arms of such conductive terminals have to be designed in a curved long arm shape due to the abutment demand, which may cause the current path of the conductive terminal becoming very long, thereby affecting its high frequency characteristics and limiting its transmission rate.
Hence, an electrical contact with improved structure is desired.
To achieve the above object, an electrical contact for connecting a chip module to a print circuit board, the electrical contact comprises a main body, an upper elastic arm and a lower mounting arm extending upwardly from the main body, and a lower elastic arm and a lower mounting arm extending downwardly from the main body. The upper mounting arm is disposed at the downside of the upper elastic arm and forms a space therebetween; the lower mounting arm is disposed at the downside of the lower elastic arm and forms a space therebetween. The upper elastic arm and the lower elastic arm are respectively deformed by the chip module and print circuit board to resist to the upper mounting arm and lower mounting arm, thereby shortening the current path between the chip module and the print circuit board for improving the high frequency performance of an electrical connector.
Other advantages and novel features of the invention will become more apparent from the following detailed description of the present embodiment when taken in conjunction with the accompanying drawings.
Referring to
The upper elastic arm (unit) 11 includes a first bending portion 111 extending from the upper end of the main body 10 toward to the direction away from the main body 10, a second bending portion 112 bending upwardly from the first bending portion 111, an arc-shaped upper contacting portion 113 extending upwardly from the second bending portion 112 to the upside of the main body 10; and the lower elastic arm (unit) 13 includes a third bending portion 131 extending from the downside of the main body 10 to the direction away from the main body 10, a forth bending portion 132 bending downwardly from the third bending portion 131, and an arc-shaped lower contacting portion 133 extending downwardly from the forth bending portion 132 to the downside of the main body 10, the upper and lower elastic arms 11,13 are U-shaped with an opening facing to the plane where the main body 10 located. Both the upper and lower elastic arms 11,13 define a slit 15 passing through the upper and lower end of the main body 10, the upper and lower mounting arms 12,14 are disposed at the slits 15 of upper and lower elastic arms 11,13 and protruding out of the corresponding slits 15.
The main body 10 includes a plurality of barbs 101 protruding from its left and right sides, and a pair of carriers 102 extending vertically from the upper end of the main body 10, said two carriers 102 are located on the two sides of the upper arm 11.
The upper mounting arm 12 comprises a first extending portion 121 extending vertically and an upper abutting portion 122 extending obliquely from the upper end of the first extending portion 121, the lower mounting arm 14 comprises a second extending portion 141 extending vertically and a lower abutting portion 142 extending obliquely from the lower end of the second extending portion 141.
The upper and lower abutting portions 122,142 and the upper and lower contacting portions 113,133 are set interval and disposed at the other side of the plane where the main body 10 located. The length of the upper and lower mounting arms 12,14 are shorter than the length of the corresponding upper and lower elastic arms 11,13.
The upper elastic arm 11 and the lower elastic arm 13 are symmetrically disposed at the center of the main body 10, and the upper mounting arm 12 and the lower mounting arm 14 are symmetrically disposed at the center of the main body 10, thereby being good for the symmetrically elastic deformation of the upper and lower elastic arms 11,13 and lengthen the service life of the electrical contact 100.
Referring to
When the electrical contact 100 is assembled between the chip module 102 and the circuit board 101, the upper elastic arm 11 is crimped to the upper abutting portion 122 of the upper mounting arm 12, and the lower elastic arm 13 is crimped to the lower abutting portion 142 of the lower mounting arm 14, to form a parallel conductive paths, respectively, to reduce the total impedance value, and to shorten current path of the chip module 102 and the print circuit board 101 comparing with the conventional elastic contact that only transmitting the current through the curved and long arm-shaped elastic arm, thereby improving the high frequency characteristics of the electrical contact 100 and increasing the transmission speed of the electrical terminals.
Referring to
The retaining section 22 includes a main base 220 and opposite upper support/mounting arms 221 and lower support/mounting arm 222 respectively located at two opposite upper and lower ends of the main base 220. Notably, during compression, the upper spring arm 211 contacts the upper support arm 221, and the lower spring arm 212 contacts the lower support arm 222. The bridge 23 is linked between the main body 210 of the deflectable section 21 and the main base 220 of the retaining section 22. The upper spring arm 211 includes a first (upper) bending section 2111 linked to the main body 210, an (upper) horizontal section 2112 extending from the first (upper) bending section 2111 toward the main base 220, a second (upper) bending section 2113 extending upwardly from the (upper) horizontal section 2112, an (upper) vertical/abutment section 2114 extending upwardly from the second (upper) bending section 2113, and an upper contacting section 2115 extending from the (upper) vertical section 2114 toward the main base 220. Symmetrical to the upper spring arm 211, the lower spring arm 212 included a first (lower) bending section 2111, a (lower) horizontal section 2112, a (lower) second bending section 2113, a (lower) vertical/abutment section 2114, and a lower contacting section 2116 arranged in a mirror image manner with the upper spring arm 211.
The housing 1 forms upper standoffs 110 on the top surface 11 and lower standoffs 120 on the bottoms surface 12. The upper spring arm 211 extends upwardly beyond the upper standoffs 110, and the lower spring arm 212 extends downwardly beyond the lower standoffs 120. The upper support arm 221 is located between the top surface 11 and the upper standoffs 110, and the lower support arm 222 is located between the bottom surface 12 and the lower standoffs 120. When the CPU and the printed circuit board are respectively positioned upon the uppers standoffs 110 and the lower standoffs 120, the upper spring arm 211 and the lower spring arm 212 are respectively deflected and further abut against the corresponding upper support arm 221 and the lower support arm 222, respectively, illustrated later.
The retaining section 22 includes the (planar) main base 220 and the barbs 2201 on two lateral sides for engagement within the passageway 10. The main body 210 and the main base 220 are parallel to each other with the bridge 23 horizontally extending therebetween. The bridge 23 is essentially located at the mid-level of the whole contact 2 so as to have the whole contact 2 symmetrically arranged in the vertical direction. The upper support arm 221 and the lower support arm 222 extend obliquely away from the upper spring arm 211 and the lower spring arm 212 so as to comply with extension configuration of the upper spring arm 211 and that of the lower spring arm 212. In other words, the oblique upper support arm 221 extends not only upwardly but also sideward away from the main base 220 perpendicular to the plane defined by the main base 220. Similarly the oblique lower support arm 212 extends not only downwardly but also sideward away from the main base 220 perpendicular to the plane defined by the main base 220.
When the upper spring arm 211 is downwardly pressed by the CPU, the upper spring arm 211 moves along the upper support arm 221. Similarly, when the lower spring arm 212 is upwardly pressed by the printed circuit board, the lower spring arm 212 moves along the lower support arm 222. In detailed analysis, the (upper) vertical/abutment section 2114 abuts against the upper support arm 221, and the (lower) vertical/abutment section 2114 abuts against the lower support arm 222 so as to assure no yielding around the (upper/lower) first bending section 2111.
From an electrical viewpoint, during operation dual electrical paths are formed between the upper contacting section 2115 and the lower contacting section 2116, of which one is made via the deflectable section 21 only, and the other is made via assistance of the retaining section 22. Notably, the upper spring arm 211 and the lower spring arm 212 along the first electrical path essentially perform the required mechanical characteristics, e.g., provision of the proper normal force, while the upper support arm 221 and the lower support arm 222 along the second electrical path essentially perform the required electrical characteristics, e.g., provision of the shorter path and the lower impedance. The first electrical path and the second electrical path in parallel also help lowering the impedance.
Although the present invention has been described with reference to particular embodiments, it is not to be construed as being limited thereto. Various alterations and modifications can be made to the embodiments without in any way departing from the scope or spirit of the present invention as defined in the appended claims.
Understandably, there are several common features in both the upper embodiment and the second embodiment wherein the upper elastic arm in the first embodiment is analogous to the upper spring arm in the second embodiment, and the upper mounting arm in the first embodiment is analogous to the upper support arm in the second embodiment. Similarly, the lower elastic arm in the first embodiment is analogous to the lower spring arm in the second embodiment, and the lower mounting arm in the first embodiment is analogous to the lower support arm in the second embodiment. The main body with barbs on the lateral side edges in the first embodiment is analogous to the main base with barbs on the lateral side edges in the second embodiment. The essentially difference between the first embodiment and the second embodiment is that in the first embodiment the upper elastic arm and the lower elastic arm respectively extend from the main body in an U-shaped configuration while in the second embodiment the upper spring arm and the lower spring arm commonly extend from the main body which is opposite to and connected to the main base via the bridge. Theoretically speaking, in the second embodiment the whole deflection section 21 associated with the bridge 23 can be deemed deflectable or deformable. This is the reason why the deflectable section 21 is curved rather than being planar during operation as shown in
Understandably, the contact disclosed in the first embodiment is used in an electrical connector having the corresponding housing similar to what is disclosed in the second embodiment. For example, in the first embodiment of
In brief, in both first embodiment of
Number | Date | Country | Kind |
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201820615657.2 | Apr 2018 | CN | national |
201820624878.6 | Apr 2018 | CN | national |