Abstract:
An USB memory card ( 100 ) for mating with a receptacle connector includes a PCB ( 1 ) having opposed upper and lower surfaces; a set of metal contacting pads ( 13 ) disposed on the upper surface of the PCB; a metal shell ( 5 ) enveloping the upper surface of the PCB and collaborating with the upper surface to form a receiving space ( 101 ) for receiving a tongue plate of the receptacle connector; and a metal film ( 15 ) covering the lower surface of the PCB.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to an USB memory card, and more particularly to an USB memory card having an insulator for retaining resilient contacts. 
         [0003]    2. Description of Related Art 
         [0004]    Rapid advances in technology in several areas have converged to enable small, portable memory cards with vast capacities. Flash memory technologies such as those using electrically-erasable programmable read-only memory (EEPROM) have produced chips storing 512 M-Bytes or more. Small flash-memory cards have been designed with a connector that can plug into a specialized reader, such as for compact-flash, secure-digital, memory stick, or other standardized formats. Recently, memory cards are being sold that contain an USB 2.0 connector. Such USB 2.0 memory cards do not require a specialized reader but can be plugged into an USB connector on a host system, such as a personal computer (PC). These USB 2.0 memory cards can be used in place of floppy disks. An USB 2.0 memory card can have a capacity of more than ten floppy disks in an area not much larger than a large postage stamp. 
         [0005]    In 2008, USB 3.0 specification has been released for transmitting high speed rate. Therefore, a memory card with an USB 3.0 connector is needed to be designed to take place of the USB 2.0 memory card. 
         [0006]    Hence, an improved USB memory card is desired to overcome the above problems. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    According to one aspect of the present invention, an USB memory card comprises a printed circuit board defining opposite first and second surfaces, the printed circuit board having a plurality of passageways passing through said first and second surfaces; a plurality of metal contacting pads formed on the first surface of the printed circuit board and before said passageways in a front-to-back direction; and a contact module including an insulator secured to the printed circuit board, and a plurality of resilient contacts defining resilient contacting portions for being movable in the corresponding passageways along a height direction of the USB memory card, tail portions for being mounted to the printed circuit board, and connecting portions connecting the contacting portions and the tail portions for being retained in the insulator. 
         [0008]    According to another aspect of the present invention, an USB 3.0 thin card comprises a printed circuit board defining a base portion and a tongue portion extending forwardly from the base portion, the tongue portion having a plurality of metal contacting pads disposed on an upper surface thereof, and a plurality of passageways passing therethrough in a height direction of the USB 3.0 thin card and located behind the metal contacting pads in a front-to-back direction; a contact module including an insulator disposed on a lower surface of the printed circuit board, and a plurality of resilient contacts comprising resilient contacting portions protruding upwardly into the corresponding passageways and beyond the upper surface of the printed circuit board, tail portions for being mounted to the printed circuit board, and connecting portions connecting the contacting portions and the tail portions for being retained in the insulator; and a shell covering the printed circuit board and the contact module with the metal contacting pads and the contacting portions exposed to exterior. 
         [0009]    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. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which: 
           [0011]      FIG. 1  is an assembled, perspective view of an USB memory card according to a first embodiment of the present invention; 
           [0012]      FIG. 2  is a partly exploded perspective view of the USB memory card shown in  FIG. 1 ; 
           [0013]      FIG. 3  is similar to  FIG. 2 , but viewed from another aspect; 
           [0014]      FIG. 4  is an exploded perspective view of the USB memory card shown in  FIG. 1 ; 
           [0015]      FIG. 5  is similar to  FIG. 4 , but viewed from another aspect; 
           [0016]      FIG. 6  is a cross-sectional view of the USB memory card taken along line  6 - 6  shown in  FIG. 1 ; 
           [0017]      FIG. 7  is an assembled, perspective view of an USB memory card according to a second embodiment of the present invention; 
           [0018]      FIG. 8  is an exploded perspective view of the USB memory card shown in  FIG. 7 . 
           [0019]      FIG. 9  is a cross-sectional view of the USB memory card taken along line  9 - 9  shown in  FIG. 7 . 
           [0020]      FIG. 10  is an assembled, perspective view of an USB memory card according to a third embodiment of the present invention; 
           [0021]      FIG. 11  is an exploded perspective view of the USB memory card shown in  FIG. 10 ; 
           [0022]      FIG. 12  is a cross-sectional view of the USB memory card taken along line  12 - 12  shown in  FIG. 10 ; 
           [0023]      FIG. 13  is an assembled, perspective view of an USB memory card according to a fourth embodiment of the present invention; 
           [0024]      FIG. 14  is an exploded perspective view of the USB memory card shown in  FIG. 13 ; and 
           [0025]      FIG. 15  is a cross-sectional view of the USB memory card taken along line  15 - 15  shown in  FIG. 13 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0026]    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. 
         [0027]    Referring to  FIGS. 4 and 5 , an USB memory card  100  according to a first embodiment of the present invention is adapted for mating with an USB 3.0 or USB 2.0 receptacle connector (not shown) and comprises a printed circuit board (named as PCB hereinafter)  1 , a contact module coupled to the PCB  1 , a shell  4  and a cover  5  covering the PCB  1  and the contact module. 
         [0028]    Referring to  FIGS. 1-6 , the PCB  1  includes a base portion  10  and a tongue portion  11  extending forwardly from a front end of the base portion  10 . The base portion  10  defines a plurality of metal soldering pads  12  formed on a lower surface thereof and a pair of through holes  15  passing therethrough in a height direction of the USB memory card  100 . The tongue portion  11  has a plurality of metal contacting pads  13  formed on an upper surface thereof and arranged in a front row along a transverse direction for mating with the receptacle connector, and a plurality of passageways  14  passing therethrough in the height direction and arranged in a back row along the transverse direction. The passageways  14  are located between the contacting pads  13  and the soldering pads  12 . The contacting pads  13  are formed by golden fingers of the PCB  1 . 
         [0029]    The contact module includes an insulator  3  and a plurality of resilient contacts  2  coupled to the insulator  3 . Each resilient contact  2  has a tail portion  23  for being soldered on the soldering pad  12 , a resilient contacting portion  21  being movably received in the corresponding passageway  14  for mating with the receptacle connector, and a connecting portion  22  connecting the contacting portion  21  and the tail portion  23 . The contacting portion  21  bends upwardly and extends forwardly from a front end of the connecting portion  22 . The contacting portion  21  has an arc portion  211  bowed upwardly and protruding upwardly beyond the upper surface of the tongue portion  11 . A free end portion  213  is located at a front end of the arc portion  211  for moving freely in the height direction of the USB memory card  100 . The tail portion  23  bends upwardly and extends backwardly from a rear end of the connecting portion  22 . The connecting portions  22  are assembled to a plurality of cavities  32  formed on the insulator  3 , the insulator  3  is located between the passageways  14  and the soldering pads  12 , a pair of posts  35  protrude upwardly from an upper surface of the insulator  3  for being retained into the through holes  15  of the PCB. therefore, the resilient contact  2  and the insulator  3  are formed together as the contact module for being assembled to the PCB  1 , the tail portions  23  could be soldered on the soldering pads  12  securely, and when the resilient contacting portions  21  are deflected by the receptacle connector, the tail portions  23  will not be deflected and will electrically connect to the soldering pads  12  reliably. Each connecting portion  22  has a set of projections  225  projecting from two lateral sides thereof for interferentially engaging with the corresponding cavity  32 . 
         [0030]    The resilient contacts  2  comprise two pairs of differential contacts and a grounding contact located between the two pairs of differential contacts. The metal contacting pads  13  are adapted for USB 2.0 protocol. The metal contacting pads  13  and the resilient contacts  2  are commonly adapted for USB 3.0 protocol. The metal contacting pads  13  and the contacting portions  21  are located on the upper surface of the tongue portion  11  and are arranged in two rows along a front-to-back direction. In other embodiments, the connecting portions  22  of the resilient contacts  2  could be insert molded into the insulator  3  so that the resilient contacts  2  could be retained in the insulator  3  firmly. The USB memory card  100  using the PCB  1 , the metal contacting pads  13  and the resilient contacts  2  to form as an USB 3.0 memory card will diminish the cost of production and miniaturize the volume of the USB memory card  100 . 
         [0031]    Referring to  FIGS. 1-6 , the shell  4  envelopes the insulator  3  and the tongue portion  11  for retaining the insulator  3  and the tongue portion  11  together. The shell  4  has a depression  41  recessed downwardly from an upper surface thereof and defining a plurality of first receiving slots  42  for exposing the metal contacting pads  13  to exterior, and a plurality of second receiving slots  43  locating behind the depression  41  for exposing the arc portions  211  of the resilient contacts  21  to the exterior. 
         [0032]    Referring to  FIGS. 7-9 , An USB memory card  100  according to a second embodiment of the present invention is disclosed and is much similar to the first embodiment. The differences between them are that the base portion  10  has a plurality of perforations  16  passing therethrough, the tail portions  23  bend upwardly from the rear ends of the corresponding connecting portions  22  and are mounted through the perforations  16  of the PCB  1 , therefore, the tail portions  23  of the resilient contacts  2  are mounted to the base portion  10  of the PCB  1  by through hole technology (THT). 
         [0033]    Referring to  FIGS. 10-12 , An USB memory card  100  according to a third embodiment of the present invention is disclosed. The differences between the first and third embodiments are that the soldering pads  12  are formed on a lower surface of the tongue portion  11 , the tail portions  23  of the resilient contacts  2  bend upwardly and extend forwardly from the front ends of the connecting portions  22  so as to be soldered on the soldering pads  12  respectively, the contacting portions  21  of the resilient contacts  2  bending upwardly and extending forwardly from the rear ends of the connecting portions  22  so as to enhance their elastic force, each contacting portion  21  has a rib  212  formed on an upper surface of the arc portion  211  so that the contacting portions  21  could contacting with the receptacle connector reliably. The insulator  3  is located under the tongue portion  11  and between the soldering portions  12  and the passageways  14 . In this third embodiment, the tail portions  23  of the resilient contacts  2  are mounted onto the tongue portion  11  of the PCB  1  by surface mount technology (SMT), therefore, the base portion  10  will have more spaces on its lower surface for disposing passive components or oscillators or other components, a length of the base portion along a front-to-back direction could be decreased so as to diminish the volume of the USB memory card  100 . 
         [0034]    Referring to  FIGS. 13-15 , An USB memory card  100  according to a fourth embodiment of the present invention is disclosed. The differences between the first and fourth embodiments are that the soldering pads  12  are formed on a lower surface of the tongue portion  11 , the tail portions  23  of the resilient contacts  2  bend upwardly and extend forwardly from the front ends of the connecting portions  22  to be soldered on the soldering pads  12  respectively, the contacting portions  21  of the resilient contacts  2  bending upwardly and extending backwardly from the rear ends of the connecting portions  22 , the free end portions  213  are formed at rear ends of the arc portions  211  and are resisted downwardly by the shell  4 . The insulator  3  is located under the tongue portion  11  and between the soldering portions  12  and the passageways  14 . In this fourth embodiment, the tail portions  23  of the resilient contacts  2  are mounted onto the tongue portion  11  of the PCB  1  by surface mount technology (SMT), therefore, the base portion  10  will have more spaces on its lower surface for disposing passive components or oscillators or other components, a length of the base portion along a front-to-back direction could be decreased so as to diminish the volume of the USB memory card  100 . 
         [0035]    It is to be understood, however, that even though numerous, characteristics and advantages of the present invention have been set fourth in the foregoing description, together with details of the structure and function of the invention, the disclosed is illustrative only, and changes may be made in detail, especially in matters of number, 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.