Electrical connector with improved grounding contact

[0001] 1. Field of the Invention

[0002] The present invention relates to electrical connectors, more particularly to electrical connectors with improved grounding contact in order to provide reasonable space for easily receiving a fiber optical lens module.

[0003] 2. Description of Related Art

[0004] U.S. Pat. No. 5,769,666 discloses an electrical connector including an insulative housing, a plurality of contacts retained in the housing and a metal shield received in the housing. The contacts include contact portions and bending portions extending downwardly from rear ends of the contact portions. The bending portions are perpendicular to the contact portions and include contractive tail portions for being soldered to a PCB. The metal shield encloses the contact portions for EMI protection. The bending portions are arranged side by side at a rear wall of the housing. The bending portions occupy much area of the rear wall of the housing as a result that the rear wall of the housing doesn't have reasonable area for mounting additional components from a rear-to-front direction.

[0005] Hence, an improved electrical connector is desired to overcome the above problems.

[0006] An electrical connector for being mounted on a PCB includes a housing member, a plurality of contacts attached to the housing member and a metal shell enclosing the housing member. The contacts include a plurality of first contacts having deformable first contact portions and a plurality of second contacts having stiff second contact portions under a condition that the first and the second contact portions are located at a same side of the housing member. The first and the second contact portions are respectively arranged side by side along parallel transverse directions. The first and the second contact portions offset from each other along a longitudinal direction perpendicular to the transverse directions. The second contacts include a first pair of differential contacts, a second pair of differential contacts and a grounding contact disposed therebetween. The first contacts and the first and the second pairs of differential contacts are used for being soldered to the PCB while the grounding contact needn't be soldered to the PCB. The grounding contact comprises a grounding tab opposite to the corresponding second contact portion to attach to the metal shell for grounding purpose. As a result, a relative wider and integral space can be provided between the first and the second contacts for easily mounting a fiber optical lens module.

[0007] The foregoing has outlined rather broadly the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention.

[0018] In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, it will be obvious to those skilled in the art that the present invention may be practiced without such specific details. In other instances, well-known circuits have been shown in block diagram form in order not to obscure the present invention in unnecessary detail. For the most part, details concerning timing considerations and the like have been omitted inasmuch as such details are not necessary to obtain a complete understanding of the present invention and are within the skills of persons of ordinary skill in the relevant art.

[0019] Reference will be made to the drawing figures to describe the present invention in detail, wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by same or similar reference numeral through the several views and same or similar terminology.

[0020] Referring to FIGS. 1-5, an electrical connector 100 defines a mating end for receiving a complementary connector (not shown) and a mounting end for being mounted on a printed circuit board (PCB, not shown). According to the preferred embodiment of the present invention, the electrical connector 100 is an optical/electrical connector and includes a housing member 1, a plurality of contacts 2 attached to the housing member 1 and a metal shield 3 enclosing the housing member 1. The housing member 1 includes a first insulative housing 11 and a second insulative housing 12 received in the first insulative housing 11. The separate first and second insulative housings 11, 12 can facilitate assembly of the contacts 2, which will be detailed hereinafter.

[0021] Referring to FIGS. 6 and 7, the first insulative housing 11 includes a base portion 13 and a tongue plate 14 extending forwardly from a front face 131 of the base portion 13. The tongue plate 14 extends along a longitudinal direction A-A as shown in FIG. 7. The base portion 13 includes a bottom mounting wall 138 and a rear face 133 opposite to the front face 131. A mounting post 139 is provided extending downwardly from the mounting walls 138 for being received in a corresponding through hole (not shown) defined in the PCB so that the electrical connector 100 can be firmly mounted on the PCB. A pair of parallel first slits 134 are recessed from the rear face 133 along the longitudinal direction A-A for regulating the contacts 2. The first slits 134 are located at opposite lateral sides of the first insulative housing 11. Besides, a through hole 135 is provided extending through the rear face 133 along the longitudinal direction A-A under a condition that the through hole 135 is adapted for receiving a fiber optical lens module 8 (shown in FIGS. 2, 5&8) in order to enhance high speed signal transmission of the electrical connector 100. The fiber optical lens module 8 has a main body 81, a pair of guiding posts 82 extending forwardly from the main body 81 and two pairs of optical components 83 between the guiding posts 82. In assembly, the fiber optical lens module 8 is optically connected to a precision block on the PCB (the PCB and the precision block not shown) for mating with another fiber optic of the complementary connector which is mateable with the electrical connector 100. The base 13 includes a rectangular shaped receiving cavity 136 throughout the front and the rear faces 131, 133 for receiving the second insulative housing 12. The receiving cavity 136 is located over the through hole 135 and is in communication with the first slits 134. The base 13 includes a top surface 137 and an opening 132 in communication with the receiving cavity 136. The opening 132 extends upwardly through the top surface 137 and extending backwardly through the rear face 133 for accommodating the corresponding contact.

[0022] The tongue plate 14 includes a free end 141 opposite to the base portion 13, a receiving opening 142 communicating with the receiving cavity 136, and a receiving base 143 located between the free end 141 and the receiving opening 142 along the longitudinal direction A-A. The receiving base 143 defines a plurality of parallel rectangular depressions 1431 communicating with the receiving opening 142, and then forms a plurality of projections 1432 separating the adjacent two depressions 1431 for ESD protection. Each depression 1431 extends along the longitudinal direction A-A as well.

[0023] The second insulative housing 12 includes opposite first and second ends 121, 122, and a plurality of second slits 123 recessed from the second end 122 for regulating the contacts 2. The second insulative housing 12 further defines a plurality of passageways 125 formed on opposite upper and lower sides thereof for mounting the contacts 2.

[0024] As shown in FIGS. 4-8, the contacts 2 include a plurality of first contacts 21 and a plurality of second contacts 22. The first contacts 21 include a power contact 2a, a ground contact 2b, a first signal contact 2c and a second signal contact 2d disposed side by side along the transverse direction B-B. The second contacts 22 include a first pair of differential contacts 22a, a second pair of differential contacts 22b and a grounding contact 22c located between the first and the second pairs of differential contacts 22a, 22b. Each first contact 21 includes an L-shaped first main portion 211, an elastic first contact portion 212 at one end of the first main portion 211, and a first bending portion 213 extending downwardly from the other end of the first main portion 211. The first main portion 211 has a certain width thereof and located in a horizontal plane. The other end of the first main portion 211 includes opposite lateral edges 214, 215 in the horizontal plane. The first bending portion 213 bends downwardly from one of the lateral edges 214, 215 and substantially perpendicular to the first main portion 211. The first bending portions 213 are regulated in the second slits 123 for preliminary position. The first bending portion 213 further includes a contractive first soldering portion 216 at a distal end thereof and extending downwardly to be soldered to the PCB.

[0025] Each second contact 22 includes a second main portion 221 and a stiff second contact portion 222 at one end of the second main portion 221. The second main portions 221 are located over the first main portions 211. The second contact portions 222 are parallel to the second main portions 221 while are located below the second main portions 221. Each differential contact 22a, 22b has a second bending portion 223 extending downwardly from the other end of the second main portion 221. The second main portions 221 are located in a horizontal plane. The other end of the second main portion 221 includes opposite lateral edges 224, 225 in the horizontal plane. The second bending portion 223 bends downwardly from one of the lateral edges 224, 225 and substantially perpendicular to the second main portion 221. The second bending portions 223 are regulated in the first slits 134 for preliminary position. The second bending portion 223 further includes a contractive second soldering portion 226 at a distal end thereof and extending downwardly to be soldered to the PCB.

[0026] Referring to FIGS. 6&9, the grounding contact 22c of the second contacts 22 is step shaped with its second main portion 221 located over its second contact portion 222. Besides, the grounding contact 22c further includes a grounding tab 228 extending backwadly and upwardly from the second main portion 221. The grounding tab 228 extends cantileveredly from the second main portion 221 and is located over the second main portion 221 to attach to the metal shield 3 for grounding purpose.

[0027] Referring to FIGS. 4-8, in assembly, the first and the second contacts 21, 22 are attached to the second insulative housing 12 from upper and lower sides thereof to form a contact module 20. The first and the second main portions 211, 221 are retained in the corresponding passageways 125 of the second insulative housing 12, and the second bending portions 223 extend through the second slits 123 for preliminary positioning. As shown in FIGS. 4&5, the second contact portions 222 further extend beyond the first end 121 of the second insulative housing 12. Besides, the grounding tab 228 extends cantileveredly over the second main portion 221. Then, the contact module 20 is jointly received in the receiving cavity 136 and the receiving opening 142 from a rear-to-front direction along the longitudinal direction A-A. The second contact portions 222 are received in the corresponding depressions 1431 of the tongue plate 14. At the mating end of the electrical connector 100, the first and the second contact portions 212, 222 are located at the same side of the housing member 1 while offset from each other along the longitudinal direction A-A. The first contact portion 212 deformably extends beyond the second insulative housing 12. The second bending portions 223 are received in the first slits 134 of the base portion 13. As best shown in FIG. 5, the first and the second soldering portions 216, 226 are arranged in only first and second parallel rows at opposite sides of the housing member 1, among which, in the first row, the first soldering portions 216 of the power contact 2a and the first signal contact 2c are aligned with the second soldering portions 226 of the first pair of differential contacts 22a. Similarly, in the second row, the first soldering portions 216 of the ground contact 2b and the second signal contact 2d are aligned with the second soldering portions 226 of the second pair of differential contacts 22b. The first and the second soldering portions 216, 226 are disposed at the mounting end of the electrical connector 100 for being soldered to the PCB.

[0028] As shown in FIGS. 4 and 5, each first or second bending portion 213, 223 has a first width W1 viewed from a left-to-right direction parallel to the transverse direction B-B, and a second width W2 viewed from the rear-to-front direction parallel to the longitudinal direction A-A, wherein the second width W2 is much narrower than the first width W1. As a result, the first and the second bending portions 213, 223 occupy a small space of a rear side of the first insulative housing 11 and left adequate space between the first and the second rows for insertion of the fiber optical lens module 8. Besides, at the mounting end of the electrical connector 100 as shown in FIG. 5, either in the first or in the second row, the most shortest space P1 between one of the first and one of the second soldering portions 216, 226 is much larger than any internal space P2 between the adjacent two first soldering portions 216 and any internal space P2 between the adjacent two second soldering portions 226. As a result, the performance of the differential to common mode conversion of the electrical connector 100 can be improved.

[0029] Referring to FIGS. 6 and 7, the metal shield 3 is in a tube shape, which defines a top wall 31, a bottom wall 32 opposite to the top wall 31 and a pair of sidewalls 33 connecting the top wall 31 and the bottom wall 32. The metal shield 3 is secured to the base portion 13 of the first insulative housing 11 to enclose the tongue plate 14 and the second insulative housing 12. The metal shield 3 encloses the housing member 1 to form a receiving space 30 to which the first and the second contact portions 212, 222 are exposed. The pair of guiding posts 82 of the fiber optical lens module 8 extend forwardly into the receiving space 30 for guiding insertion of the corresponding connector. The two pairs of optical components 83 are exposed to the receiving space 30 for mating with the corresponding connector. Each of the top and bottom walls 31, 32 and the pair of sidewalls 33 include at least one spring arm 34 projecting into the receiving space 30 for abutting against the corresponding connector for retaining and grounding purposes.

[0030] With the contact module 20 received in the receiving cavity 136 from the rear-to-front direction along the longitudinal direction A-A, the grounding tab 228 of the grounding contact 22c is mainly accommodated in the opening 132 to attach to an inner side of the top wall 31. However, attachment means may be in form of, but not limited to soldering or spring finger engagement. According to the present invention, the grounding contact 22c needn't be soldered to the PCB so that no soldering portion bending from the second main portion 221 is needed to extend through a space between the first and the second rows. As a result, a much integral space between the first and the second rows can be provided for receiving the fiber optical lens module 8.

[0031] The electrical connector 100 is compatible to the existing standard USB 2.0 plug which only has corresponding plug contacts for mating with the first contact portions 212. However, a USB 3.0 plug with essentially shape of the standard USB 2.0 plug while with additional contacts for mating with the second contacts 22 and/or the fiber optical lens module 8 can also be received in the electrical connector 100 for high signal transmission.

[0032] It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.