Patent Publication Number: US-6210195-B1

Title: Card edge connector with card retaining means

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a card edge connector, and particularly to a card edge connector having retaining means for retaining an inserted daughter board in position. 
     2. Description of Prior Art 
     To meet the ever-increasing requirements of expanding computer memory, a card edge connector is commonly used to interconnect an inserted daughter board with a mother board on which the connector is mounted. In the prior art, an auxiliary retainer is commonly provided for retaining the daughter board in the card edge connector thereby insuring a reliable connection therebetween. 
     A currently used conventional retainer typically comprises a U-shaped body for receiving a card edge connector, and a pair of vertical recessed arms for retaining edges of an inserted daughter board. Such a retainer is mounted to a mother board, using means such as bolts and nuts. Pertinent devices are disclosed in Taiwan Patent Application Nos. 86215468 and 86219634. The assembly process of such a design is tedious and time-consuming. In addition, an auxiliary tool must be used during assembly and disassembly of the retainer, which is inconvenient. Furthermore, such a design compromises the integrity of the mother board due to the provision of holes therein for extension of the bolts and nuts. Too many components are also required thereby complicating shipping and handling. 
     Taiwan Patent Application No. 82205007 discloses another conventional retainer. As shown in FIG. 8, the retainer consists of a clasping member  40  and a separate vertical member  44  for respectively preventing upward and lateral movements of a daughter board  46  inserted into a card edge connector  47 . The clasping member  40  comprises opposite first and second clasping ends  41  and  42 , and a resilient portion  43  formed between the clasping ends  41  and  42 . The first clasping end  41  has an engaging hook  410  attached to the bottom of the connector  47  by double-face adhesive tape. The second clasping end  42  has a clasp  420  for clasping an upper edge of the daughter board  46 . The vertical member  44  is provided on an inner surface of a computer enclosure  45  and comprises two parallel strips for sandwiching a longitudinal edge of the daughter board  46 . This arrangement requires two components, i.e., the clasping member  40  and the vertical member  44 , to retain the daughter board  46  in position, thereby complicating manufacturing and increasing material waste, which results in high costs. In addition, it is difficult to attach the vertical member  44  to the inner surface of the computer enclosure  45 . 
     The present invention is directed at solving the aforesaid problems by providing a card edge connector which can retain an inserted daughter board in position without the need of an auxiliary retainer thereby reducing manufacturing costs and the number of components. 
     SUMMARY OF THE INVENTION 
     Accordingly, one object of the present invention is to provide a card edge connector having retaining means formed thereon for retaining an inserted daughter board in position thereby eliminating the need of an auxiliary retainer. 
     Another object of the present invention is to provide a card edge connector with reduced number of components thereby facilitating manufacturing and reducing costs. 
     In order to achieve the objects set forth, a card edge connector in accordance with the present invention comprises an insulative housing defining an elongate slot for receiving a daughter board therein, an engaging arm formed on a longitudinal end of the housing with a receiving hole defined therethrough, a locking member for locking into the receiving hole of the arm, and a plurality of contacts received in passageways defined in the housing. 
     The receiving hole of the engaging arm may be a through hole or a polygonal hole. The locking member may have various forms, such as a locking pin, a resilient pin, a planar pin, or a combination of a resilient pin and an engaging post. In assembly, the locking member sequentially extends through a notch defined in a longitudinal edge of the daughter board and the receiving hole of the engaging arm. The locking member locks into the receiving hole and abuts against a lower edge of the notch of the daughter board to prevent the inserted daughter board from moving upward. The engaging arm abuts against a side surface of the daughter board and the locking member abuts against an opposite side surface of the daughter board thereby preventing a lateral movement of the inserted daughter board relative to the connector. Thus, the daughter board is securely retained in the connector. 
     Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an exploded view of a card edge connector having an engaging arm with a through hole defined therein, and a locking member in the form of a pin to be inserted into the through hole in accordance with the present invention, and a daughter board to be inserted into the connector; 
     FIG. 2 is an assembled view of FIG. 1; 
     FIG. 3 is a view similar to FIG. 1 but incorporating a locking member in the form of a locking pin; 
     FIG. 4 is a view similar to FIG. 1 but incorporating a locking member in the form of a resilient pin; 
     FIG. 5A is a view similar to FIG. 1 but incorporating a locking member in the form of a resilient pin and an engaging post to be inserted into the resilient pin in a first direction; 
     FIG. 5B is a view similar to FIG. 5A but with the engaging post to be inserted into the resilient pin in an opposite direction; 
     FIG. 6 is an exploded view of a card edge connector having an engaging arm with a polygonal hole defined therein, and a locking member in the form of a planar pin to be rotatably locked into the polygonal hole in accordance with another embodiment of the present invention, and a daughter board to be inserted into the connector; 
     FIGS. 7A and 7B are schematic views illustrating sequential engagements between the polygonal hole and the planar pin of FIG. 6; and 
     FIG. 8 is a perspective view of a conventional card edge connector retaining an inserted daughter board by a clasping member and a vertical member. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made to the drawing figures to describe the present invention in detail. 
     Referring to FIG. 1, a card edge connector  1  in accordance with the present invention comprises an insulative housing  10  having a pair of opposite side walls  18 , an elongate slot  12  defined between the opposite side walls  18  for receiving a daughter board  2  therein, and a plurality of contacts  16  received in corresponding passageways  14  defined in the side walls  18 . The contacts  16  are adapted for engaging with corresponding conductive pads (not shown) proximate the bottom of the inserted daughter board  2  to establish an electrical connection between the daughter board  2  and a mother board (not shown) on which the connector  1  is mounted. 
     The connector  1  further comprises card retaining means  3  for retaining the inserted daughter board  2  in position. The retaining means  3  includes an engaging arm  30  outwardly extending from a longitudinal end of the housing  10  with a through hole  32  defined therein, and a locking member in the form of a cylindrical pin  5 . A notch  22  is defined in a longitudinal edge of the daughter board  2  proximate the bottom thereof. The pin  5  sequentially extends through the notch  22  of the inserted daughter board  2  and the through hole  32  of the connector  1 . The pin  5  locks into the through hole  32  of the engaging arm  30  and abuts against a lower edge  220  of the notch  22  of the daughter board  2  thereby preventing the inserted daughter board  2  from moving upward, as shown in FIG.  2 . 
     The locking member of the retaining means  3  may have various forms to cooperate with the through hole  32  of the engaging arm  30  for retaining the inserted daughter board  2  in position, as illustrated in FIGS. 3 to  5 B. 
     The locking member as illustrated in FIG. 3 is in the form of a locking pin  51 . The locking pin  51  comprises a body  510  for sequentially extending through the notch  22  of the inserted daughter board  2  and the through hole  32  of the connector  1 , and a stop  512  having a larger diameter than the body  510 . The body  510  abuts against the lower edge  220  of the notch  22  of the daughter board  2  to prevent an upward movement of the daughter board  2 . The stop  512  of the locking pin  51  and the engaging arm  30  respectively abut against a side surface  24  and an opposite side surface of the daughter board  2  to prevent a lateral movement of the daughter board  2 . Thus, the inserted daughter board  2  is retained in position. 
     FIG. 4 illustrates a locking member in the form of a resilient pin  52 . The resilient pin  52  comprises a head  522  and a stop  524  formed on opposite ends thereof, and a body  520  between the head  522  and the stop  524 . A groove  526  is defined in the body  520  and the head  522  for providing resiliency thereof. The head  522  tapers toward a free end thereof having the largest diameter proximate the body  520  and larger than the body  520 , and the stop  524  has a diameter larger than both of the body  520  and the head  522 . The body  520  has a diameter slightly larger than the through hole  32  of the engaging arm  30 . In assembly, the head  522  and the body  520  sequentially extend through the notch  22  of the daughter board  2  and the through hole  32  of the connector  1 . The head  522  is compressed and then resiliently resumes its original shape to bias against the engaging arm  30 . The body  520  is resiliently received in the through hole  32  and abuts against the lower edge  220  of the notch  22  of the daughter board  2 . The stop  524  of the resilient pin  52  and the engaging arm  30  respectively abut against the side surface  24  and the opposite side surface of the daughter board  2  to prevent a lateral movement of the daughter board  2 . Thus, the inserted daughter board  2  is retained in position. 
     The locking member  53  illustrated in FIG. 5A includes a resilient pin  531  and an engaging post  533 . The resilient pin  531  is similar to the resilient pin  52  in FIG. 4 except that a passage  538  is defined therethrough in communication with a groove  536  defined in a body  530  and a head  532  thereof. In assembly, the head  532  and the body  530  of the resilient pin  531  sequentially extend through the notch  22  of the daughter board  2  and the through hole  32  of the connector  1 . The engaging post  533  then extends through the passage  538  of the resilient pin  531  in the same direction as the resilient pin  531  thereby securely locking the resilient pin  531  into the through hole  32  to retain the inserted daughter board  2  in position. 
     FIG. 5B illustrates that the engaging post  533  can also be inserted into the passage  538  of the resilient pin  531  in a reversed direction relative to the insertion direction of the resilient pin  531 . 
     FIG. 6 shows a card edge connector  1  in accordance with another embodiment of the present invention. A polygonal hole  32 ′ is defined in the engaging arm  30 . The locking member is in the form of a planar pin  54  comprising a planar portion  540  for rotatably engaging with the polygonal hole  32 ′ and a stop  542  for abutting against the daughter board  2 . The planar portion  540  sequentially extends through the notch  22  of the daughter board  2  and the polygonal hole  32 ′ of the connector  1  in an initial position whereby the planar portion  540  is horizontally retained in the polygonal hole  32 ′ as illustrated in FIG.  7 A. The planar pin  54  is then rotated clockwise to move the planar portion  540  thereof to a final position whereby the planar portion  540  is vertically retained in the polygonal hole  32 ′ as illustrated in FIG.  7 B. In the final position, the planar portion  540  abuts against the lower edge  220  of the notch  22  of the daughter board  2 . The stop  542  of the planar pin  54  and the engaging arm  30  respectively abut against the side surface  24  and the opposite side surface of the daughter board  2  to prevent a lateral movement of the daughter board  2 . Thus, the inserted daughter board  2  is securely retained in position. 
     Due to the provision of the engaging arm  30  of the connector  1 , and a locking member  5 ,  51 ,  52 ,  53  and  54 , upward and lateral movements of the inserted daughter board  2  are prevented thereby retaining the daughter board  2  in position. Thus, the need of an auxiliary retainer is eliminated, thereby simplifying manufacturing, reducing manufacturing costs and facilitating assembly. 
     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.