Patent Abstract:
A card connector ( 200 ) with a reinforcing structure ( 230 ) is provided for used in a handheld device. The card connector can mate with an elongated expansion card ( 10 ) which when inserted into the card connector has a portion located outside the handheld device. The card connector comprises an insulated main body ( 210 ) and a plurality of terminals ( 220 ) fixed to the main body. The terminals are used for electrically connecting the elongated expansion card with a printed circuit board ( 20 ) on which the card connector is mounted. The reinforcing structure ( 230 ) is formed from highly rigid material or high molecular weight polymer. The reinforcing structure strengthens the card connector against any external force resulting from subjecting the elongated expansion card to an external force, whereby the electrical connection between the terminals and printed circuit board will not break due to the external force.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the priority benefit of Taiwan application serial no. 92205187, filed on Apr. 2, 2003. 
     BACKGROUND OF INVENTION 
     1. Field of Invention 
     The present invention relates to a card connector. More particularly, the present invention relates to a card connector with a reinforcing structure. 
     2. Description of Related Art 
     Personal digital assistant (PDA) is a versatile portable device used by professional and non-professional people alike. The design concept of a personal digital assistant is to provide a user with an electronic (digital) notebook capable of registering and sorting out important data that may be of some help in managing travel schedules, organizing meetings, and providing communication memos. With the big leap in the operating speed of computers, the ease of Internet connection and the advance in wireless communication technologies, most personal digital assistants now provide a variety of functions including wireless communication, network accessing, playing games and multimedia services. PDA is frequently regarded as a “palm-top computer”. 
     In general, a PDA has a built-in data storage device with moderate data storage capacity for holding user&#39;s files and data. However, to provide extra data storage capacity, a small memory card can be added to the PDA. At present, a large number of memory cards with many different types of specifications are found in the market. The most common memory cards are the secure digital card (SD Card) and the compact-flash card (CF Card). To utilize an external memory card as an extra data storage device, a card connector capable of accommodating a memory card of the desired specifications must be installed on the PDA. When a memory card is properly plugged into the card connector on the PDA, file or data can read, write or erase through signals carried via the card connector. In addition, elongated expansion cards for plugging into the card connector of a PDA at one end and protruding outside the PDA at the other end are also available in the market. The elongated expansion card includes, for example, a digital camera card for capturing image or picture data from a miniature digital camera or a wireless local area network (WLAN) card for connecting up with a wireless local area network (WLAN). 
     FIG. 1A is a top view of a conventional PDA card connector  100  and an elongated expansion card  10  to be inserted into the card connector  100 . As shown in FIG. 1A, the card connector  100  has an insulation body  110  and a plurality of terminals  120 . The insulation body  110  is an integrative unit having two side beams  112 ,  114  and a horizontal beam  116  joined together to form a U-shaped frame. Typically, the insulation body  110 ,is made from plastic with some areas strengthened and OLE_LINK 2 protected from electrostatic dischargeOLE_LINK 2  by incorporating some metallic casing material (not shown). Furthermore, the side beams  112 ,  114  have sliding grooves  112   a ,  114   a  suitable for accommodating the two edges of the elongated expansion card  10  such as a digital camera card or a wireless local area network (WLAN) card. The horizontal beam  116  defines a terminal plugging slot  118  for receiving the front ends of the socket terminals  12  of the expansion card  10 . In addition, terminals  120  are positioned on the horizontal beam  116 . One end of the terminal  120  is a free end  122  while the other end is a fixed end  124 . The free end  122  of the terminal  120  extends in the terminal plugging slot  118 . When the front end of the elongated expansion card  10  is plugged into the terminal plugging slot  118 , the free ends  122  of the terminals  120  are elastically pressed and electrically connected to the socket terminals  12  of the elongated expansion card  10 . Meanwhile, the fixed ends  124  of the terminals  120  extend beyond the horizontal beam  116  and are fixed and electrically connected to a printed circuit board  20 . 
     Note that the fixed ends  124  of the terminals  120  of the conventional card connector  100  are fixed onto the printed circuit board  20  through surface mounting technology due to the limit space within a PDA. However, with further miniaturization of the PDA, the thickness of the PDA body is further reduced. Because one end of the elongated expansion card  10  is exposed outside the PDA body  30  as shown in FIG. 1B, any external forces acting on the elongated expansion card  10  (such as dropping the PDA vertically onto the floor) will be directly transmitted to the card connector  100 . As a result of the impact on the card connector  100 , the fixed ends  124  of the terminals  120  will likely break away from the printed circuit board  20  and lead to a failed connection. Worse, the loose card connector  100  can possibly further impinge on other electronic components (not shown) on the printed circuit board  20  to damage the normal function of the PDA. 
     SUMMARY OF INVENTION 
     Accordingly, one object of the present invention is to provide a card connector with a reinforcing structure for reinforcing the strength of the card connector. 
     To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a card connector with a reinforcing structure set up on a circuit board. The card connector comprises an insulated main body, a plurality of terminals and a reinforcing structure. The insulated body has two side beams and a horizontal beam. The side beams are attached to the respective ends of the horizontal beam to form a U-shaped frame body. The side beams each have a sliding groove capable of accommodating the two side edges of aplug-in elongated expansion card. Furthermore, the horizontal beam has at least a terminal plugging slot for accommodating the socket terminals of the elongated expansion card. In addition, terminals are set up in the horizontal beam with one end of each terminal extending towards the terminal plugging slot and the other end of the terminal extending away from the terminal plugging slot. The ends of the terminals away from the terminal plugging slot are in turn fastened and electrically connected to the printed circuit board by surface mounting technology. The reinforcing structure is set up on one side of the horizontal beam away from the terminal plugging slot. The reinforcing structure includes a bump bar fixed over the circuit board. The bump bar has a comb shaped surface for engaging a vertical rear surface of the horizontal beam. Furthermore, the teeth of the comb roughly occupy the space between the ends of neighboring terminals. 
     According to one embodiment of this invention, the bump bar is attached to the printed circuit board through surface mounting. Besides, the bump bar can have a threaded bolt extension that can pass through the printed circuit board and the reinforcing structure includes a lock nut that can screw onto the threaded bolt to lock the printed circuit board and the bump bar tightly together. Furthermore, the top end of the bump bar may incorporate a pressing block that contacts top surface of the horizontal beam to increase the strength at the top end of the insulated body. 
     According to one embodiment of this invention, the reinforcing structure can be a screw and with the bump bar having an internally threaded hole. The screw passes through the printed circuit board and screws into the threaded hole in the bump bar so that the printed circuit board and the bump bar are locked tightly together. Furthermore, the top end of the bump bar may incorporate a pressing block engaging a top surface of the horizontal beam to increase the strength of the connector in resisting an external force. In addition, the reinforcing structure can be a screw and a nut and with the bump bar having a through hole. The screw passes through the through hole in the bump bar and the printed circuit board so that the nut can be screwed onto the exposed end of the screw to lock the bump bar and the printed circuit board together. 
     According to a further embodiment of this invention, the reinforcing structures can beattached to the outer casing of the PDA. The bump bar is riveted to the outer casing and located between the outer casing and the printed circuit board. A screw extends from a bottom of the printed circuit board through the printed circuit board to threadedly engage in the bump bar. Thus, the outer casing, the bump bar and the printed circuit board are connected together. Still a further embodiment of the present invention, the reinforcing structure has a shielding securely fixed to the card connector. The shielding has a portion extending rearwards to a position behind the terminals of the connector. A screw extends through the extended portion of the shielding and the printed circuit board to threadedly engage with a nut at a bottom face of the printed circuit. The screw has a head abutting against a vertical portion of the shielding, whereby a forced acting on the connector can be effectively resisted by the assistance of the reinforcing structure. 
     This invention deploys a reinforcing structure to strengthen the card connector. Hence, the fixed terminals on the card connector are protected against electrical disconnection due to impact forces acting on the elongated expansion card (due to a free fall of the PDA body from a high point to the ground). 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS 
     The accompanying drawings are included to provide further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. 
     FIG. 1A is a top view of a conventional PDA card connector and an elongated expansion card to be inserted into the connector. 
     FIG. 1B is a diagram showing a falling handheld device, for example a PDA likely to subject the elongated expansion card and the card connector to an impact force. 
     FIG. 2 is a diagram showing a card connector assembly with a reinforcing structure according to one preferred embodiment of this invention. 
     FIGS. 3A to  3 E are sectional views showing five different types of reinforcing structures on a card connector assembly according to this invention. 
     FIG. 3F is a sectional view of an alternative reinforcing structure on a card connector assembly for the one in FIG.  3 B. 
     FIG. 3G is a sectional view of an alternative reinforcing structure on a card connector assembly for the one in FIG.  3 C. 
     FIG. 4 is a sectional view of a reinforcing structure on a card connector assembly according to a further embodiment of this invention. 
     FIG. 5 is a sectional view of a reinforcing structure on a card connector assembly according to a still further embodiment of this invention. 
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
     FIG. 2 is a diagram showing a card connector  200  with a reinforcing structure according to one preferred embodiment of this invention and an elongated expansion card  10  to be inserted into the connector  200 . The card connector  200  has an insulation body  210 , a plurality of terminals  220  and a reinforcing structure  230 . The insulation body  210  is, for example, an integrative unit having two side beams  212 ,  214  and a horizontal beam  216  joined together to form a U-shaped frame. Typically, the insulation body  210  is made from plastic with some areas strengthened and protected from electrostatic discharge by incorporating some metallic casing material (not shown). Furthermore, the side beams  212 ,  214  have sliding grooves  212   a ,  214   a  suitable for accommodating the two edges of the elongated expansion card  10  such as a digital camera card or a wireless local area network (WLAN) card. The horizontal beam  216  has a terminal plugging slot  218  for receiving the front ends of the socket terminals  12  of the expansion card  10 . In addition, terminals  220  are positioned on the horizontal beam  216  of the insulated body  210  with the terminals  220  attached to the circuit board  20  through surface mounting. One end of the terminal  220  (the free end)  222  extends towards the terminal plugging slot  218  to engage elastically and connect electrically with a socket terminal  12  in the elongated expansion card  10 . Meanwhile, the other end  224  of the terminals  220  (the fixed end) extends beyond the horizontal beam  216  and soldered to a printed circuit board  20  via surface mounting technology so that the terminal is fastened and electrically connected to the printed circuit board  20 . 
     The reinforcing structure  230  or the strengthening structure for the connector is positioned behind the horizontal beam  216  (away from the terminal plugging slot) to reinforce the card connector  200  against any impact on the elongated expansion card  10 . The reinforcing structure  230  has a comb-shaped bump surface  232  that corresponds with the vertical rear surface  216 a of the horizontal beam  216  (as shown in FIG.  3 A). The comb-shaped bump surface  232  crosses over the fixed ends  224  of the terminals  220  but avoids any contact with the fixed ends  224 . The reinforcing structure  230  can be fabricated using high strength material including, for example, stainless steel alloy or other metallic material. Alternatively, a high molecular weight polymer compound with a high degree of hardness such as acrylic can be used to fabricate the reinforcing structure  230 . However, because plastic material has a high degree of insulation, short circuit can be prevented even if there is a direct contact of the comb-shaped bump surface  232  with the fixed end  224  of the terminal  220 . In the following, a description of each type of reinforcing structure is described using a diagram with the understanding that material, shape and thickness of the reinforcing structure may be modified accordingly without departing from the scope of this invention. 
     FIG. 3A is a sectional view showing a first type of reinforcing structure on a card connector assembly according to this invention. As shown in FIG. 3A, the reinforcing structure  230  has a bump bar  240  fastened to the circuit board  20  by soldering, for example. The bump bar  240  has a comb-shaped bump surface  242  that corresponds with the vertical rear surface  216 a of the horizontal beam  216 . When the elongated expansion card  10  is subjected to an impact force, the comb-shaped bump surface  242  on the bump bar  240  is able to strengthen the horizontal beam  216  structurally. Therefore, the fixed ends  224  of the terminals  220  in the card connector  200  will remain electrically connected despite the impact acting on the connector  200  from the elongated expansion card  10 . 
     FIG. 3B is a sectional view showing a second type of reinforcing structure on a card connector assembly according to this invention. As shown in FIG. 3B, the reinforcing structure  230  has at least a bump bar  250  and a nut  254 . The bump bar  250  has a threaded bolt  251  that passes through the circuit board  20 . The nut  254  is screwed onto the protruded bolt  251  and hence the bump bar  250  and the circuit board  20  are tightened together. The bump bar  250  also has a comb-shaped bump surface  252  that is located abutting the vertical rear surface  216   a  of the horizontal beam  216 . When the elongated expansion card  10  is subjected to an impact force, the comb-shaped bump surface  252  on the bump bar  250  is able to strengthen the horizontal beam  216  structurally. Thus, the fixed ends  224  of the terminals  220  in the card connector  200  will remain electrically connected with the printed circuit board  20  despite the impact force. 
     FIG. 3C is a sectional view showing a third type of reinforcing structure on a card connector assembly according to this invention. As shown in FIG. 3C, the reinforcing structure  230  includes a bump bar  260  and a screw  264 . In addition, the bump bar  260  has a threaded hole  261 . The screw  264  passes through the circuit board  20  and screws into the threaded hole  261  so that the bump bar  260  and the circuit board  20  are tightened together. The bump bar  260  also has OLE_LINK 1   a  comb-shaped bump surface  262  that corresponds with the vertical rear surface  216   a  of the horizontal beam  216 OLE_LINK 1 . When the elongated expansion card  10  is subjected to an impact force, the comb-shaped bump surface  262  on the bump bar  260  is able to strengthen the horizontal beam  216  structurally. Thus, the fixed ends  224  of the terminals  220  in the card connector  200  will remain electrically connected with the printed circuit board  20  despite the impact. 
     FIG. 3D is a sectional view showing a fourth type of reinforcing structure on a card connector assembly very similar to the one in FIG.  3 C. The reinforcing structure  230  is set up inside the outer casing  276  of a PDA body as shown in FIG.  3 D. Preferably, the outer casing  276  is used for accommodating the circuit board  20  and other components inside the PDA. The reinforcing structure  230  at least includes a bump bar  270  and a screw  274 . The bump bar  270  is riveted to the interior sidewall of the outer casing  276  or is manufactured as an integral part to the interior sidewall of the outer casing  276 . In addition, the bump bar  270  has a threaded hole  271 . The screw  274  passes through the circuit board  20  and screws into the threaded hole  271  so that the bump bar  270 , the outer casing  276  and the circuit board  20  are tightened together. The bump bar  270  also has a comb-shaped bump surface  272  abutting the vertical rear surface  216 a of the horizontal beam  216 . When the elongated expansion card  10  is subjected to an impact force, the comb-shaped bump surface  272  on the bump bar  270  is able to strengthen the horizontal beam  216  structurally. Thus, the fixed ends  224  of the terminals  220  in the card connector  200  will remain electrically connected with the printed circuit board  20  despite the impact force. 
     FIG. 3E is a sectional viewshowing a fifth type of reinforcing structure on a card connector assembly very similar to the one in FIG.  3 D. The reinforcing structure  230  is similarly strengthened through the outer casing  276  of a PDA body. The reinforcing structure  230  includes a bump bar  280 , a screw  284  and a nut  286 . The screw  284  passes through the outer casing  276 , the bump bar  280  and the circuit board  20 . The nut  286  is screwed onto the exposed end of the screw  284  so that the circuit board  20  and the bump bar  280  are tightened to the outer casing  276 . The bump bar  280  also has a comb-shaped bump surface  282  that corresponds with the vertical rear surface  216   a  of the horizontal beam  216 . When the elongated expansion card  10  is subjected to an impact force, the comb-shaped bump surface  282  on the bump bar  280  is able to strengthen the horizontal beam  216  structurally. Thus, the fixed ends  224  of the terminals  220  in the card connector  200  will remain electrically connected with the printed circuit board  20  despite the impact force. 
     FIG. 3F is a sectional view of an alternative reinforcing structure on a card connector assembly for the one in FIG.  3 B. The reinforcing structure  230  also includes a bump bar  250  and a nut  254 . However, the top end of the bump bar  250  has an additional pressing block  256  touching the upper end of the horizontal beam  216  to strengthen the upper end of the horizontal beam  216 . FIG. 3G is a sectional view of an alternative reinforcing structure on a card connector assembly for the one in FIG.  3 C. The reinforcing structure  230  has a step-like bump bar  266  and a screw  264 . The bump bar has a rear plate  267  located in rear of the terminals  224  and engaging with the printed circuit board  20 . A threaded hole is defined in the rear plate  267 . The screw  264  extends upwardly through the printed circuit board  20  to threadedly engage in the threaded hole thereby securely connecting the bump bar  266  and the printed circuit board  20  together. The bump bar abuts against the vertical rear surface  216 a of the horizontal beam  216 . Furthermore, the top end of the bump bar  266  has an additional pressing block  268  pressing the upper end of the horizontal beam  216  to strengthen the upper end of the horizontal beam  216 . 
     FIG. 4 is a sectional view of a reinforcing structure on a card connector assembly according to a further embodiment of this invention. As shown in FIG. 4, a reinforcing structure  330  includes a metallic shielding  340  and a screw  332 /nut  3334  assembly  330 . The shielding  340  is fixedly secured to an insulated body  310  of the card connector. The shielding  340  strengthens the insulated body  310  and provides electrostatic protection to the card connector and the elongated expansion card  10 . The shielding  340  extends rearwards behind the horizontal beam  316  of the insulated body  310  and the terminals of the card connector and has a fixing hole (not labeled) thereon. The fixing hole is located above the circuit board  20  behind the horizontal beam  316  and the terminals. The screw  332  extends through the fixing hole of the shielding  340  and the printed circuit board  20  to threadedly engage with the nut  334  by thread  331 . The screw  332  has a head (not labeled) abutting against a vertical part of the shielding  340 , whereby an impact force acting on the connector from the elongated expansion card  10  can be effectively resisted by the reinforcing structure  330 , and, thus, the terminals of the connector can have a reliable electrical connection with the printed circuit board  20 , regardless of the impact force. 
     FIG. 5 is a sectional view of a reinforcing structure on a card connector assembly according to still a further embodiment of this invention. One major aspect that differs from the other embodiments is that the reinforcing structure is attached to the interior sidewall of the outer casing  440  of a PDA as an integrative unit. The interior sidewall of the outer casing  440  includes at least a bump spine  432  with a slant surface  434 . The slant surface  434  is positioned to contact the corner region of the horizontal beam  416  so that a portion of the impact force can be absorbed by the bump spine  432 . When the elongated expansion card  10  is subjected to an impact force, the bump spine  432  reinforces the horizontal beam  416  of the insulated body  410  so that the terminals in the card connector can be electrically connected to the printed circuit board  20 . 
     In summary, the reinforced card connector structure of this invention comprises a card connector, an insulated body, a plurality of terminals and a reinforcing structure. The reinforcing structure is fabricated using any high strength material or high molecular weight polymer compound such as stainless steel alloy or hardened acrylic material. Therefore, any impact forces acting on the elongated expansion card (such as dropping the PDA vertically down onto the floor) will be redirected to the reinforced card connector  100  and absorbed. As a result, the force acting on the fixed ends of the terminals within the card connector is minimized and a failed connection due to the terminals tearing away from the printed circuit board is highly unlikely. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.

Technology Classification (CPC): 7