Electrical connector with specially designed metal contact terminals to avoid solder-off

An electrical connector includes an electrically insulative holder member, a signal module formed of a circuit board with longitudinal terminal holes, circuit lines, electrical contacts and via-holes, metal contact terminals and metal mounting terminals, and a metal shield. The metal contact terminals have rear soldering end portions thereof soldered to respective circuit lines, an extension arm forwardly extended from the rear soldering end portion along one longitudinal terminal hole, a turn portion extended from the extension arm and curved into the associating longitudinal terminal hole to enhance vertical deformation stroke of the respective metal contact terminal, a front contact portion suspending below the associating longitudinal terminal hole, and an oblique spring arm connected between the turn portion and the front contact portion to flexibly support the front contact portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to electrical connector technology and more particularly, to an electrical connector with specially designed metal contact terminals, which avoids permanent deformation of metal terminals or solder-off.

2. Description of the Related Art

Following fast development of computer technology, high mobility notebook computer has been well developed and widely used by people to substitute for desk computer. Further, when connecting a computer to a peripheral apparatus for transmitting data or signal, a peripheral interface means is necessary. USB (universal serial bus) is the mainstream interface, having hot plug function.

Further, following the market trend to make computers and peripheral devices having a small size characteristic, the problem of internal signal interference due to magnetic effects must be taken into account. Interferences may come from conducted disturbance that occurs during signal transmission through power circuits and/or signal lines of the circuit board to the electrical connector, or radiated disturbance that occurs due to the radiation of magnetic waves around the electrical connector. As a USB 3.0 connector uses a large number of conducting terminals that are arranged in a limited mounting area, approaching between two conducting terminals or curving of any conducting terminal may cause disturbance (static interference, electromagnetic interference, impedance matching, noise interface, crosstalk interference) during the transmission of a high-frequency signal. Further, EMI (electromagnetic interference) and noises can be eliminated or reduced during signal transmission between a USB 3.0 connector and a system mainboard interface only if impedance matching condition is satisfied. Improper impedance matching can cause signal reflection and noise interference, resulting in signal loss, signal deformation and/or signal distortion. When this problem occurs, the electronic system (computer or network system) may be unable to function normally.

Further, a circuit board design of tongue plate has copper foil contacts arranged on a plane. For example, an HDMI socket connector is based on this design. Further, a circuit board design of tongue plate for USB 3.0 female connector has 5 pcs of copper foil contacts and 4 pcs of springy metal contact terminals. When a USB 3.0 male connector is inserted into a USB 3.0 female connector, the arrangement of the springy metal contact terminals at the circuit board design of tongue plate of the USB 3.0 female connector may causes serious mechanism problems. The first problem is that the positioning of the front contact portions of the springy metal contact terminals on the top side of the circuit board design of tongue plate may be directly impacted by the mating metal contact terminals of the USB 3.0 male connector, due to positioning displacement or large tolerance, causing disconnection of the spring metal contact terminals from the circuit board design of tongue plate. The second problem is that the springy metal contact terminals may be squeezed toward the circuit board design of tongue plate by a lateral force upon insertion of the USB 3.0 male connector into the USB 3.0 female connector, causing damage or disconnection of the rear soldering portions of the springy metal contact terminals from the circuit board design of tongue plate. A third problem is that the circuit board design of tongue plate has no room for allowing the springy metal contact terminals to be elastically and heavily deformed and the springy metal contact terminals may be permanently deformed.

Therefore, it is desirable to provide an electrical connector, which eliminates the aforesaid problems.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide an electrical connector, which avoids permanent deformation of metal terminals or solder-off.

To achieve this and other objects of the present invention, an electrical connector comprises an electrically insulative holder member, a signal module mounted in the holder member, and a metal shield surrounding the holder member and the signal module. The electrically insulative holder member comprises a holder base, and a tongue plate suspending in the front side of the holder base. The tongue plate comprises at least one opening in the bottom side thereof and five contact holes arranged in a transverse line in a front side relative to the at least one opening. The signal module comprises a circuit board, which comprises a plurality of longitudinal terminal holes, a plurality of circuit lines, a plurality of electrical contacts and a plurality of via-holes, a plurality of metal contact terminals, and a plurality of metal mounting terminals. The metal contact terminals are respectively mounted in the circuit board corresponding to the longitudinal terminal holes, each comprising a rear soldering end portion electrically soldered to one circuit line, an extension arm forwardly extended from said rear soldering end portion along a top side of one said longitudinal terminal hole, a turn portion extended from one end of said extension arm opposite to said rear soldering end portion and curved into the associating longitudinal terminal hole and stopped at a front end of the associating longitudinal terminal hole, a front contact portion suspending below the associating longitudinal terminal hole outside said circuit board, and an oblique spring arm connected between said turn portion and said front contact portion. The metal mounting terminals are respectively soldered to the via-holes of the circuit board.

As the extension arms are supported on the inside wall inside the insertion chamber of the tongue plate and the turn portions are respectively stopped at the front ends of the respective longitudinal terminal holes, the extension arms and the turn portions limit the extent of deformation of the oblique spring arms, avoiding excessive deformation of the metal contact terminals or disconnection of the rear soldering end portions of the metal contact terminals from the respective soldered points.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Reference will be made in detail to the preferred embodiment of the invention, an example of which is illustrated in the accompanying drawings. Wherever possible, like reference numbers are used in the drawings and the description to refer to like parts.

Referring toFIGS. 1,2,3and4, an elevational view, an exploded view, an exploded view viewed from another angle and a sectional side view in an enlarged scale of an electrical connector in accordance with the present invention are respectively shown. The electrical connector comprises an electrically insulative holder member1, a signal module2, and a metal shield3.

The electrically insulative holder member1comprises a holder base11, a tongue plate12, and a partition block13. The holder base11defines an accommodation open chamber10in the rear bottom side thereof, and two inside retaining flanges111symmetrically disposed at two opposite lateral sides in the accommodation open chamber10. The tongue plate12suspends in the front side of the holder base11, defining an insertion chamber120therein, at least one opening121in a bottom side thereof in communication with the insertion chamber120, and five contact holes122in a transverse line in front of the at least one opening121. The partition block13defines a plurality of through holes131vertically cut through opposing top and bottom sides thereof and arranged in two lines, and two coupling flanges132symmetrically disposed at two opposite lateral sides corresponding to the inside retaining flanges111of the holder base11.

The signal module2comprises a horizontally extending circuit board21, a plurality of metal contact terminals22, and a plurality of metal mounting terminals23. The circuit board21defines therein a plurality of longitudinal terminal holes210, a plurality of circuit lines211, a plurality of electrical contacts212, and a plurality of via-holes213. The metal contact terminals22are respectively set in the longitudinal terminals holes210of the circuit board21, each comprising a rear soldering end portion221electrically soldered to one respective circuit line211at the circuit board21, an extension arm222forwardly extended from the rear soldering end portion221along the top side of one respective longitudinal terminal hole210, a turn portion223extended from one end of the extension arm222opposite to the rear soldering end portion221and curved into the respective longitudinal terminal hole210, a front contact portion225suspending below the respective longitudinal terminal hole210outside the circuit board21, and an oblique spring arm224connected between the turn portion223and the front contact portion225. According to this embodiment, the metal contact terminals22are configured subject to USB 2.0 specification, i.e., the number of the metal contact terminals22is 4; the electrical contacts212are configured to match with the metal contact terminals22subject to USB 3.0 specification, i.e., the number of the electrical contacts212is 5; the electrical contacts212and the front contact portion225are respectively arranged in a respective line in a staggered manner; the number of the via-holes131is 9, i.e., four via-holes131are arranged in a first line at the front side and the other five via-holes131are arranged in a second line at the rear side. Further, the metal contact terminals22and the electrical contacts212are respectively electrically connected to the via-holes213by the circuit lines211. The metal mounting terminals23are respectively soldered to the via-holes213and vertically downwardly extended from the circuit board2.

Further, the rear soldering end portions221of the metal contact terminals22and the metal mounting terminals23are respectively soldered to the circuit lines211and via-holes213of the circuit board21by SMT (surface mounting technology) and through-hole technology. However, this mounting arrangement is not a limitation. SMT (surface mounting technology) and through-hole technology may be selectively employed to solder the rear soldering end portions221of the metal contact terminals22and the metal mounting terminals23to the circuit lines211and the via-holes213subject to different design requirements. Further, the circuit board21can be a single layer board, or multi-layer board. The metal shield3comprises a front receiving hole31, a rear accommodation chamber32disposed in communication with the front receiving hole31, and two bottom mounting legs33respectively downwardly extended from two opposite lateral sides thereof.

Referring toFIGS. 1-4again, during installation of the electrical connector, solder the rear soldering end portions221of the metal contact terminals22and the metal mounting terminals23to the circuit lines211and the via-holes213of the circuit board21respectively, and then insert the circuit board21forwardly through the accommodation open chamber10of the holder base11into the insertion chamber120of the tongue plate12to keep the front contact portions225of the metal mounting terminals23suspending outside the at least one opening121of the tongue plate12and simultaneously to force the electrical contacts212into the respective contact holes122. Thereafter, attach the partition block13upwardly to the inside of the accommodation chamber10of the holder base11to let the metal mounting terminals23be respectively inserted through the respective through holes131of the partition block13and the coupling flanges132be respectively forced into engagement with the inside retaining flanges111of the holder base11. Thus, the signal module2is positively positioned in the accommodation chamber10of the holder base11. Thereafter, wrap the metal shield3about the electrically insulative holder member1and the signal module2to have the electrically insulative holder member1be positioned in the rear accommodation chamber32of the metal shield3and the circuit board21with the tongue plate12be positioned in the front receiving hole31. Thus, the 5 pcs of electrical contacts212of the circuit board21are respectively disposed in the contact holes122of the tongue plate12; the metal contact terminals22are spaced behind the electrical contacts212in a staggered manner with the front contact portions225thereof suspending outside the at least one opening121of the tongue plate12; the circuit lines211respectively electrically connect the electrical contacts212and the metal contact terminals22to the 9 pcs of via-holes213.

Referring toFIG. 5andFIGS. 2-4again, when using the electrical connector, a mating (USB male) connector4is inserted into the front receiving hole31of the metal shield3, and the internal front flat terminals41and rear conducting terminals42of the mating (USB male) connector4are respectively forced into contact with the metal contact terminals22and the electrical contacts212of the signal module2. However, when moving the front flat terminals41of the mating (USB male) connector4toward the metal contact terminals22, the front contact portions225of the metal contact terminals22will be respectively stopped against the front flat terminals41of the mating (USB male) connector4to deform the associating oblique spring arms224toward the inside of the respective longitudinal terminal holes210. As the extension arms222are supported on the inside wall inside the insertion chamber120of the tongue plate12and the turn portions223are respectively stopped at the front ends of the respective longitudinal terminal holes210, the extension arms222and the turn portions223limit the extent of deformation of the oblique spring arms224, avoiding excessive deformation of the metal contact terminals22or disconnection of the rear soldering end portions221of the metal contact terminals22from the respective soldered points (the circuit lines211). Further, subject to the design of the longitudinal terminal holes210, the front contact portions225can have a relatively greater deformation stroke in vertical direction, ensuring a high level of positioning stability of the metal contact terminals22. Thus, the design of the present invention facilitates quick installation and assures a high level of reliability.

Referring toFIG. 3again, as stated above, the signal module2comprises 5 pcs of electrical contacts212and 4 pcs of metal contact terminals22. The electrical contact212at the midpoint is for grounding. The other 4 pcs of electrical contacts212that are symmetrically disposed at two opposite lateral sides are for signal transmission. The left and right-sided metal contact terminals22are respectively the power terminal and the grounding terminal. The other two metal contact terminals22on the middle are for signal transmission. Thus, during transmission of high-frequency signal through the respective signal-transmission electrical contacts212and signal-transmission metal contact terminals22, the grounding electrical contact212and the respective grounding circuit line211guide electromagnetic waves to the respective grounding metal mounting terminal23for discharge, eliminating or reducing EMI (electromagnetic interference) and/or cross talk.

Referring toFIGS. 2,3and5again, as stated above, when the mating (USB male) connector4is inserted into the electrical connector, the internal front flat terminals41and rear conducting terminals42of the mating (USB male) connector4are respectively forced into contact with the metal contact terminals22and the electrical contacts212of the signal module2. As the extension arms222and turn portions223of the metal contact terminals22are respectively supported on the inside wall inside the insertion chamber120of the tongue plate12stopped at the front ends of the respective longitudinal terminal holes210, the extension arms222and the turn portions223of the metal contact terminals22limit the extent of deformation of the associating oblique spring arms224when the front flat terminals41of the mating (USB male) connector4are forced into contact with the front contact portions225of the metal contact terminals22, avoiding excessive deformation of the metal contact terminals22or disconnection of the rear soldering end portions221of the metal contact terminals22from the respective soldered points (the circuit lines211).