Abstract:
A cable assembly ( 100 ) includes an insulative housing ( 2 ) having a base portion ( 21 ) and a tongue portion ( 22 ) extending forwardly from the base portion, said tongue portion defining a mounting cavity ( 221 ) and at least two depressions ( 224 ), said two depressions located behind and located within the mounting cavity. An optical module ( 5 ) is accommodated in the mounting cavity, said optical module having two lenses. Two fibers ( 6 ) pass through the two depressions and coupled to the two lenses, respectively. Two cap members ( 7 ) are accommodated in the two depressions to position the fibers therein.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is related to U.S. patent application Ser. No. 11/818,100, filed on Jun. 13, 2007 and entitled “EXTENSION TO UNIVERSAL SERIAL BUS CONNECOTR WITH IMPROVED CONTACT ARRANGEMENT”, and U.S. patent application Ser. No. 11/982,660, filed on Nov. 2, 2007 and entitled “EXTENSION TO ELECTRICAL CONNECTOR WITH IMPROVED CONTACT ARRANGEMENT AND METHOD OF ASSEMBLING THE SAME”, and U.S. patent application Ser. No. 11/985,676, filed on Nov. 16, 2007 and entitled “ELECTRICAL CONNECTOR WITH IMPROVED WIRE TERMINATION”, all of which have the same assignee as the present invention. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a cable assembly, more particularly to a cable assembly capable of transmitting optical signal. 
         [0004]    2. Description of Related Art 
         [0005]    Recently, personal computers (PC) are used of a variety of techniques for providing input and output. Universal Serial Bus (USB) is a serial bus standard to the PC architecture with a focus on computer telephony interface, consumer and productivity applications. The design of USB is standardized by the USB Implementers Forum (USB-IF), an industry standard body incorporating leading companies from the computer and electronic industries. USB can connect peripherals such as mouse devices, keyboards, PDAs, gamepads and joysticks, scanners, digital cameras, printers, external storage, networking components, etc. For many devices such as scanners and digital cameras, USB has become the standard connection method. 
         [0006]    USB supports three data rates: 1) A Low Speed rate of up to 1.5 Mbit/s (187.5 KB/s) that is mostly used for Human Interface Devices (HID) such as keyboards, mice, and joysticks; 2) A Full Speed rate of up to 12 Mbit/s (1.5 MB/s). Full Speed was the fastest rate before the USB 2.0 specification and many devices fall back to Full Speed. Full Speed devices divide the USB bandwidth between them in a first-come first-served basis and it is not uncommon to run out of bandwidth with several isochronous devices. All USB Hubs support Full Speed; 3) A Hi-Speed rate of up to 480 Mbit/s (60 MB/s). Though Hi-Speed devices are advertised as “up to 480 Mbit/s”, not all USB 2.0 devices are Hi-Speed. Hi-Speed devices typically only operate at half of the full theoretical (60 MB/s) data throughput rate. Most Hi-Speed USB devices typically operate at much slower speeds, often about 3 MB/s overall, sometimes up to 10-20 MB/s. A data transmission rate at 20 MB/s is sufficient for some but not all applications. However, under a circumstance transmitting an audio or video file, which is always up to hundreds MB, even to 1 or 2 GB, currently transmission rate of USB is not sufficient. As a consequence, faster serial-bus interfaces are being introduced to address different requirements. PCI Express, at 2.5 GB/s, and SATA, at 1.5 GB/s and 3.0 GB/s, are two examples of High-Speed serial bus interfaces. 
         [0007]    From an electrical standpoint, the higher data transfer rates of the non-USB protocols discussed above are highly desirable for certain applications. However, these non-USB protocols are not used as broadly as USB protocols. Many portable devices are equipped with USB connectors other than these non-USB connectors. One important reason is that these non-USB connectors contain a greater number of signal pins than an existing USB connector and are physically larger as well. For example, while the PCI Express is useful for its higher possible data rates, a 26-pin connectors and wider card-like form factor limit the use of Express Cards. For another example, SATA uses two connectors, one 7-pin connector for signals and another 15-pin connector for power. In essence, SATA is more useful for internal storage expansion than for external peripherals. 
         [0008]    The existing USB connectors have a small size but low transmission rate, while other non-USB connectors (PCI Express, SATA, et al) have a high transmission rate but large size. Neither of them is desirable to implement modern high-speed, miniaturized electronic devices and peripherals. To provide a kind of connector with a small size and a high transmission rate for portability and high data transmitting efficiency is much more desirable. 
         [0009]    In recent years, more and more electronic devices are adopted for optical data transmission. It may be a good idea to design a connector which is capable of transmitting an electrical signal and an optical signal. Design concepts are already common for such a type of connector which is compatible of electrical and optical signal transmission. The connector includes metallic contacts assembled to an insulated housing and several optical lenses bundled together and mounted to the housing also. A kind of hybrid cable includes wires and optical fibers that are respectively attached to the metallic contacts and the optical lenses. 
         [0010]    However, In the assembly process of a connector system that uses fiber optic cables, the fibers are stiff by nature. They are also very delicate and require protection if the fibers can be exposed. An example would be, but not limited to a USB connector type of application. The fibers when assembled within the plug housing, have the tendency to drift in unwanted locations due to their stiff nature. 
       BRIEF SUMMARY OF THE INVENTION 
       [0011]    Accordingly, an object of the present invention is to provide a cable assembly has positioning means for securing fibers thereof. 
         [0012]    In order to achieve the above-mentioned object, a cable assembly in accordance with present invention comprises an insulative housing having a base portion and a tongue portion extending forwardly from the base portion, said tongue portion defining a mounting cavity and at least two depressions, said two depressions located behind and located within the mounting cavity. An optical module is accommodated in the mounting cavity, said optical module having two lenses. Two fibers pass through the two depressions and coupled to the two lenses, respectively. Two cap members are accommodated in the two depressions to position the fibers therein. 
         [0013]    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 
         [0014]    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: 
           [0015]      FIG. 1  is an assembled, perspective view of a cable assembly in accordance with the first embodiment of the present invention; 
           [0016]      FIG. 2  is an exploded, perspective view of  FIG. 1 ; 
           [0017]      FIG. 3  is similar to  FIG. 2 , but viewed from another aspect; 
           [0018]      FIG. 4  is a partially assembled view of the cable assembly; 
           [0019]      FIG. 5  is other partially assembly view of the cable assembly; 
           [0020]      FIG. 6  is a cross-section view of the cable assembly taken along line  6 - 6 ; 
           [0021]      FIG. 7  is a partially assembled view of the cable assembly in accordance with the second embodiment of the present invention; 
           [0022]      FIG. 8  is other partially assembly view of the cable assembly in accordance with the second embodiment; and 
           [0023]      FIG. 9  is an enlarged view of a cap member of the cable assembly in accordance with the second embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0024]    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. 
         [0025]    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. 
         [0026]    Referring to  FIGS. 1-6 , a cable assembly  100  according to the first embodiment of the present invention is disclosed. The cable assembly  100  comprises an insulative housing  2 , a set of first contacts  3 , a set of second contacts  4  and a optical modules  5  supported by the insulative housing  2 , and a number of fibers  6  connected to the optical module  5 . The cable assembly  1  further comprises a cap member  7  and a metal shell  8 . Detail description of these elements and their relationship and other elements formed thereon will be detailed below. 
         [0027]    The insulative housing  2  includes a base portion  21  and a tongue portion  22  extending forwardly from the base portion  21 . A cavity  211  is recessed upwardly from a bottom surface (not numbered) of the base portion  21 . A mounting cavity  221  is recessed downwardly from a top surface of the tongue portion  22  and the base portion  21 . A stopping member  2212  is formed in a front portion of the mounting cavity  221 . A positioning slot  222  is defined in a rear side of the mounting cavity  2212  and located within the mounting cavity  221 . A positioning post  2222  is arranged in the positioning slot  222 . Two depressions  224  are defined in the rear part of the tongue portion  22  and located within the mounting cavity  221 . The two depressions  224  are disposed opposite sides of the positioning slot  222 . A number of contact slots  212  are defined in an upper segment of a rear portion of the base portion  21 , and two fiber slots  214  are also defined in the upper segment of the rear portion of the base portion of the base portion  21 . The two fiber slots  214  are disposed between the two pair of adjacent fiber slots  214 , respectively. 
         [0028]    The set of first contacts  3  has four contact members arranged in a row along the transversal direction. Each first contact  3  substantially includes a planar retention portion  32  supported by a bottom surface of the cavity  211 , a mating portion  34  raised upwardly and extending forwardly from the retention portion  32  and disposed in a depression  226  of the lower section of the front segment of the tongue portion  22 , and a tail portion  36  extending rearward from the retention portion  32  and accommodated in the terminal slots  212 . 
         [0029]    The set of second contacts  4  has five contact members arranged in a row along the transversal direction and combined with an insulator  20 . The set of second contacts  4  are separated into two pair of signal contacts  40  for transmitting differential signals and a grounding contact  41  disposed between the two pair of signal contacts  40 . Each signal contact  4  includes a planar retention portion  42  received in corresponding groove  202  in the insulator  20 , a curved mating portion  44  extending forward from the retention portion  42  and disposed beyond a front surface of the insulator  20 , and a tail portion  46  extending rearward from the retention portion  42  and disposed behind a back surface of the insulator  20 . A spacer  204  is assembled to the insulator  20 , with a number of ribs  2042  thereof inserted into the grooves  202  to position the second contacts  4  in the insulator  20 . 
         [0030]    The insulator  20  is mounted to the cavity  211  of the base portion  21  and press onto retention portions  32  of the first contacts  3 , with mating portions  44  of the second contacts  4  located behind the mating portions  34  of the first contacts  3  and above the up surface of the tongue portion  22 , the tail portions  46  of the second contacts  4  arranged on a bottom surface of the rear segment of the base portion  21  and disposed lower than the tail portions  36  of the first contacts  3 . 
         [0031]    The optical module  5  includes four lens members  51  arranged in juxtaposed manner and enclosed by a holder member  52  and retained in the corresponding mounting cavity  221 . Furthermore, a coil spring member  9  is engaged with the holder member  52 , with a protrusion portion  54  of the holder member  52  extending into an interior of a front segment of the spring member  9 . A rear end of the spring member  9  is accommodated in the positioning slot  222 , and the positioning post  2222  projects into the rear end of the spring member  9 . Therefore, the optical module  5  is capable of moving backwardly and forwardly within the mounting cavity  221 . 
         [0032]    Four fibers  6  are separated into two groups and pass through the fiber slots  214 , enter the two depressions  224  and are coupled to the four lens  51 , respectively. Each cap member  7  has a body portion  72  and two crush posts  72  formed on a bottom surface thereof. The cap member  7  is assembled to the tongue portion  22 , with body portion  72  accommodated in the corresponding depression  224  to cover and secure the fibers  6  in the depression  224 , and the crush posts  72  are inserted into holes  223  in the tongue portion  22 . 
         [0033]    The metal shell  8  comprises a first shield part  81  and a second shield part  82 . The first shield part  81  includes a front tube-shaped mating frame  811 , a rear U-shaped body section  812  connected to a bottom side and lateral sides of the mating frame  811 . The mating frame  811  further has two windows  811  defined in a top side thereof. The second shield part  82  includes an inverted U-shaped body section  822 , and a cable holder member  823  attached to a top side of the body section  822 . 
         [0034]    The insulative housing  2  is assembled to the first shield part  81 , with the tongue portion  22  enclosed in the mating frame  811 , the cap members  7  arranged underneath the windows  811 , and the base portion  21  is received in the body portion  812 . The second shield part  82  is assembled to the first shield part  81 , with body portions  822 ,  812  combined together. The cable assembly may have a hybrid cable which includes fibers  6  for transmitting optical signals and copper wires (not shown) for transmitting electrical signals. The copper wires are terminated to the first contacts  3  and the second contacts  4 . The cable holder member  823  is crimped onto the cable to enhance mechanical interconnection. 
         [0035]    Referring to  FIGS. 7-9 , a cable assembly  100 ′ according to the second embodiment of the present invention is disclosed. The cable assembly  100 ′ in the second embodiment is similar with the cable assembly  100  in the first embodiment, except for a cap member  7 ′ and an insulative housing  2 ′. The cap member  7 ′ has two body portions  70 ′ arranged in parallel manner and connected together by a bridge portion  74 ′. Each body portion  70 ′ has two crush posts  72 ′ formed on a lateral side thereof. Furthermore, two crush posts  72 ′ are formed on the bridge portion  74 ′. The insulative housing  2 ′ has a depression  224 ′ which has similar configuration as the cap member  7 ′. The depression  224 ′ has two sub-depressions  2240 ′ and a channel  2242 ′ in communication with the two sub-depressions  2240 ′. Four holes  223 ′ are divided into two groups and defined in lateral sides of the tongue portion  22 ′ to receive the crush posts  72 ′ of the two body portions  70 ′. Other two holes  223 ′ are defined in the channel  2242 ′. The fibers  6  pass through the depression  224 ′ and connected to an optical module  5 . The cap member  7 ′ is accommodated in the depression  224 ′, with body portions  70 ′ located in the sub-depressions  2240 ′ respectively, the bridge portion  74 ′ received in the channel  2242 ′. Therefore, the fibers  6  are positioned in the depression  224 ′. 
         [0036]    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. For example, the tongue portion is extended in its length or is arranged on a reverse side thereof opposite to the supporting side with other contacts but still holding the contacts with an arrangement indicated by the broad general meaning of the terms in which the appended claims are expressed.