BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an electrical connector assembly, and particularly to the electrical board-to-board connector assembly.
2. Description of Related Art
A board-to-board electrical connector assembly including the mated receptacle connector and plug connector is desired not only with a low profile but also with some orientation identification structures.
SUMMARY OF THE INVENTION
An invention includes an electrical board-to-board connector assembly including a receptacle connector and a plug connector. The plug connector includes an insulative plug housing forming a mating cavity between two opposite longitudinal walls respectively equipped with two rows of plug contacts by two sides of the mating cavity. Each of the plug contacts includes an upside-down U-shaped structure straddling the longitudinal wall and including an inner arm exposed around an interior face of the corresponding longitudinal wall and an outer arm exposed around an exterior face of the corresponding longitudinal wall. A locking structure is formed in the outer arm. The receptacle connector includes an insulative receptacle housing defining two grooves located inside the corresponding two lengthwise walls and extending along a longitudinal direction to receiving the two lengthwise walls of the plug connector therein. A center island is formed between the two grooves in the transverse direction perpendicular to the longitudinal direction. Two rows of passageways are formed in the corresponding lengthwise walls, respectively, and each passageway communicates with the corresponding groove. Two rows of receptacle contacts are disposed in the corresponding passageways, respectively. Each of the receptacle contacts further includes an upside-down U-shaped structure straddling the lengthwise wall and including an inner part/arm abutting against an interior surface of the lengthwise wall, and an outer part/arm abutting against an exterior surface of the lengthwise wall wherein the inner part further includes another locking structure to interlock with the locking structure on the corresponding plug contact. The inner part is further equipped with an L-shaped extension to commonly form an upstanding U-shaped structure so as to receive and electrically and mechanically connect the upside-down U-shaped structure of the plug contact during mating. The receptacle connector optionally further includes a metallic shell enclosing the receptacle housing and unitarily forming a plurality of spring tangs extending into the corresponding passageways to replace the receptacle contacts, respectively. A portion of the lengthwise wall is thickened to allow the metallic shell attached upon the exterior surface. The center island may optionally form a pair of alignment holes to receive the corresponding optional pair of alignment poles extending from the mating cavity of the plug connector wherein the pair of alignment holes may be differently sized and the pair of alignment poles as well for single orientation consideration.
In another embodiment, the upside-down U-shaped structure of the receptacle contact is shorten with less than one half of the height of the lengthwise wall, and no longer straddles the corresponding lengthwise wall for retention but using barbed structures on the outer part of the upside-down U-shaped structure to retain the corresponding receptacle contact with in the corresponding passageway. 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.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1(A) is a downward perspective view of an electrical connector assembly including the receptacle connector and the plug connector respectively mounted upon the corresponding printed circuit boards, respectively, according to a first embodiment of the invention;
FIG. 1(B) is an upward perspective view of the electrical connector assembly of FIG. 1(A);
FIG. 2(A) is the downward exploded view of the plug connector and the corresponding printed circuit board of FIG. 1(A);
FIG. 2(B) is an upward exploded perspective view of the plug connector and the corresponding printed circuit board of FIG. 2(A);
FIG. 3(A) is a downward exploded perspective view of the receptacle connector and the corresponding printed circuit board of FIG. 1(A);
FIG. 3(B) is an upward exploded perspective view of the receptacle connector and the corresponding printed circuit board of FIG. 3(A);
FIG. 4(A) is a cross-sectional view of the electrical connector assembly of FIG. 1(A) when the receptacle connector and the plug connector are not mated with each other;
FIG. 4(B) is a cross-sectional view of the electrical connector assembly of FIG. 1(A) when the receptacle connector and the plug connector are mated with each other;
FIG. 5(A) is a downward perspective view of the electrical connector assembly including a plug connector and a receptacle connector according to the second embodiment of the invention;
FIG. 5(B) is an upward perspective view of the electrical connector assembly of FIG. 5(A);
FIG. 6(A) is a downward exploded perspective view of the plug connector of FIG. 5(A);
FIG. 6(B) is an upward exploded perspective view of the plug connector of FIG. 5(A);
FIG. 7(A) is a downward exploded perspective view of the receptacle connector of FIG. 5(A);
FIG. 7(B) is a downward perspective view of the receptacle connector of FIG. 5(A);
FIG. 8(A) is a cross-sectional view, taken along a transverse plane, of the electrical connector assembly of FIG. 5(A) when the plug connector and the receptacle connector are not mated with each other;
FIG. 8(B) is a cross-sectional view of the electrical connector assembly of FIG. 8(A) when the plug connector and the receptacle connector are mated with each other;
FIG. 9(A) is a cross-sectional view, taken along a longitudinal plane, of the electrical connector assembly of FIG. 5(A) when the plug connector and the receptacle connector are not mated with each other;
FIG. 9(B) is a cross-sectional view of the electrical connector assembly of FIG. 9(A) when the plug connector and the receptacle connector are mated with each other;
FIG. 10(A) is another cross-sectional view taken along another transverse plane, of the electrical connector assembly of FIG. 5(A) when the plug connector and the receptacle connector are not mated with each other;
FIG. 10(B) is another cross-sectional view of the electrical connector assembly of FIG. 10(A) when the plug connector and the receptacle connector are mated with each other;
FIG. 11(A) is a downward perspective view of the electrical connector assembly including a plug connector and a receptacle connector according to the third embodiment of the invention;
FIG. 11(B) is an upward perspective view of the electrical connector assembly of FIG. 11(A);
FIG. 12(A) is a downward exploded perspective view of the plug connector of FIG. 11(A);
FIG. 12(B) is an upward exploded perspective view of the plug connector of FIG. 11(A);
FIG. 13(A) is a downward exploded perspective view of the receptacle connector of FIG. 11(A):
FIG. 13(B) is an upward exploded perspective view of the receptacle connector of FIG. 11(A);
FIG. 14(A) is a cross-sectional view, taken along a transverse plane, of the electrical connector assembly of FIG. 11(A) when the plug connector and the receptacle connector are not mated with each other;
FIG. 14(B) is a cross-sectional view of the electrical connector assembly of FIG. 14(A) when the plug connector and the receptacle connector are mated with each other;
FIG. 15(A) is a cross-sectional view taken along a longitudinal plane, of the electrical connector assembly of FIG. 11(A) when the plug connector and the receptacle connector are not mated with each other;
FIG. 15(B) is a cross-sectional view of the electrical connector assembly of FIG. 15(A) when the plug connector and the receptacle connector are mated with each other;
FIG. 16(A) is a downward perspective view of an electrical connector assembly including the receptacle connector and the plug connector respectively mounted upon the corresponding printed circuit boards, respectively, according to a fourth embodiment of the invention;
FIG. 16(B) is an upward perspective view of the electrical connector assembly of FIG. 16(A);
FIG. 17(A) is the downward exploded view of the plug connector and the corresponding printed circuit board of FIG. 16(A);
FIG. 17(B) is an upward exploded perspective view of the plug connector and the corresponding printed circuit board of FIG. 17(A);
FIG. 18(A) is a downward exploded perspective view of the receptacle connector and the corresponding printed circuit board of FIG. 167(A);
FIG. 18(B) is an upward exploded perspective view of the receptacle connector and the corresponding printed circuit board of FIG. 18(A);
FIG. 19 is a cross-sectional view, taken along a transverse plane, of the electrical connector assembly of FIG. 16(A) when the receptacle connector and the plug connector are mated with each other; and
FIG. 20 is another cross-sectional view, taken along another transverse plane, of the electrical connector assembly of FIG. 16(A) when the receptacle connector and the plug connector are mated with each other.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1(A)-4(B), an electrical connector assembly 10 includes a plug connector 110 mounted upon a printed circuit board 190 for mating with a receptacle connector 150 mounted upon another printed circuit board 192. The plug connector includes an insulative housing 112 defining a pair of opposite longitudinal walls 114 extending along a longitudinal direction and a pair of opposite transverse walls 116 extending along a transverse direction perpendicular to the longitudinal direction for cooperating with the pair of longitudinal walls 114 to commonly form a receiving cavity 118. Two rows of passageways 120 are formed in the two longitudinal wall 114, respectively, and two rows of contacts 122 are disposed in the corresponding passageways 120, respectively. The contact 122 include opposite inner contacting region 124 and outer contacting/locking region 126 respectively located on opposite interior and exterior surfaces of the corresponding longitudinal wall 114. The receptacle connector 150 includes an insulative housing 152 defining a pair of opposite lengthwise walls 154 in a longitudinal direction and a pair of opposite transverse walls 156 for cooperating with the pair of lengthwise walls to form a receiving cavity 158 in which a center island 160 upwardly extends. The receiving cavity 158 includes a pair of grooves 162 to receive the corresponding longitudinal walls 114 therein, respectively. Two rows of passageways 164 are formed in the housing 152 including the corresponding lengthwise walls 114, respectively. Two rows of contacts 166 are respectively disposed in the corresponding passageways 164, respectively. Each contact 166 includes an upside-down U-shaped structure 168 straddling the lengthwise wall 154 and forming an outer locking/contacting section 170, and an L-shaped extension 172 unitarily extends from the inner arm of the upside-down U-shaped structure 168 to commonly form an upstanding U-shaped structure 174 with an inner contacting section 176 opposite to the inner contacting section 170 with the corresponding groove 162 therebetween in the transverse direction. The lengthwise wall 154 forms a thickened section 155 to protectively hide the corresponding passageways 164 and the corresponding contacts 166. A metallic shield 172 surrounds the housing 152 with mounting legs 174 mounted to the printed circuit board 192 and with contacting tabs 176 to contact the corresponding grounding ones of the corresponding contact 166.
Referring to FIGS. 5(A)-10(B), the electrical connector assembly 20 includes a plug connector 210 and a receptacle connector 250 for mating with each other. The plug connector 210 is similar to the plug connector 110, and the receptacle connector 250 is similar to the receptacle 150 except that the plug connector 210 includes a pair of different sized poles 212 and 214 in the mating cavity 218, and the center island 260 of the receptacle connector 250 forms a pair of different sized holes 252 and 254 to receive the corresponding poles 212 and 214, respectively, in a specific orientation. Moreover, the grounding ones of the receptacle contacts 266 are missing and instead the metallic shield 272 further includes the spring tangs 278 extending from the metallic shield 272 into the corresponding passageways 264 to contact the corresponding plug contacts 222, and the solder tails 280 for surface-mounting to the corresponding pads on the printed circuit board on which the receptacle connector 250 is seated.
Referring to FIGS. 11(A)-15(B), the electrical connector assembly 30 is similar to the electrical connector assembly 20 including the plug connector 310 and the receptacle connector 350 except that the poles 312 and 314 are same configured/dimensioned and the corresponding holes 352 and 354 are same configured/dimensioned to receive either pole 312 or 314 depending upon how the plug connector 310 and the receptacle connector 350 are is oriented with regard to each other.
Referring to FIGS. 16(A)-20, the electrical connector assembly 40 is similar to the electrical connector assembly 30 except that the plug connector 410 is further equipped with a pair of grounding tabs 440 attached on two lateral walls 416, and each of the transverse walls 456 of the receptacle connector 450 forms an opening 457 so as to allow the corresponding grounding tab 440 to extend therethrough to mechanically and electrically connect to the metallic shield 472. Each of the grounding tabs 440 includes a body portion 441 with barbs 444 thereon to retain to the housing in an interference fit, a mounting leg 442 extending through the printed circuit board 490 on which the plug connector 410 is seated, and a spring tab 443 resiliently abutting against the metallic shield 472 during mating. Another difference is that the contact 466 of the receptacle connector 450 includes an upside-down U-shaped structure 468 which no longer straddles the lengthwise wall but retained in the passageways 464 via barbs 465 on the outer arm 467 of the upside-down U-shaped structure 468, and is essentially only less than one half of the length of the corresponding passageway 464 in the vertical direction. The inner arm 463 of the upside-down U-shaped structure 468 no longer contacts or locks the corresponding contact 422 of the plug connector 410 wherein the outer arm 421 of the contact 422 is shortened and hidden behind the exterior surface of the longitudinal wall 414 of the housing 412 of the plug connector 410. On the other hand, the contact 466 further includes the extension 472 obliquely extending from the inner arm 469 of the upside-down U-shaped structure 468 to result in a single contact point with the corresponding contact 422 of the plug connector 410.
It is noted that some of the passageways of the receptacle connector are originally laterally exposed to an exterior while being covered by the shield. Four posts around the four corners of the housing of the receptacle connector are not covered by the shield but being exposed to an exterior. Therefore, the four posts cooperate with the bottom portion of the housing to prevent the further downward movement of the shield so as to retain the shield in position.