Abstract:
A multi-storage deck connector apparatus having at least an upper and lower storage deck is connectable to a printed circuit board. Each deck has its own set of contact pins that must make electrical connection to the printed circuit board. A vertical connector is arranged between the storage decks so that the upper storage deck contact pins are connected to the vertical connector and the vertical connector is connected to the printed circuit board. The lower storage deck contact pins are connected directly to the printed circuit board.

Description:
This application is a continuation of U.S. application Ser. No. 08/525,756 (now U.S. Pat. No. 5,906,510), filed Mar. 29, 1996, which was the National Stage of International Application No. PCT/US94/03135, filed Mar. 23, 1994. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to a connector apparatus for memory cards, and more particularly, to a connector apparatus having multiple storage decks and an improved mechanism for connecting the respective contacts of each storage deck to a printed circuit board. 
     2. Description of the Prior Art 
     Plate-like integrated circuit cards, commonly referred to in the art as “memory cards”, have become increasingly popular for use in notebook, laptop and desktop computers, as well as other consumer products. Standard specifications from the Personal Computer Memory Card International Association (PCMCIA) and the Japan Electronic Industry Development Association (JEIDA) have helped to expand this relatively new industry. Other standard specifications have been developed by the Joint Electron Device Engineering Council (JEDEC). Although commonly referred to as “memory cards,” these cards are by no means limited to data storage applications. For example, some cards may perform various I/O functions for modem and local area network applications. 
     Currently, the PCMCIA/JEIDA standard cards incorporate a 68-pin female connector at one end, and are available in three formats. Type I houses SRAM, PSRAM, MROM, OPTROM, and flash memory chips and only performs memory functions. Type I cards have a thickness of 3.3 mm. Type II cards perform I/O functions for modem and local area network (LAN) applications. The side edges of Type II cards are 3.3 mm thick, however, the main body of the cards is 5.0 mm thick. Type III cards are really not “cards,” but rather 1.8 inch hard disk drives having a 10.5 mm thick housing. Again, however, these cards are equipped with outside edges of 3.3 mm. 
     Given the increasing popularity of these “memory cards,” a need has arisen for suitable connector devices for connecting these cards to printed circuit boards in host devices, such as notebook, laptop and desktop computers. A number of connector devices have appeared in the prior art. Prior art connector devices typically comprise some sort of frame or housing into which a memory card may be inserted. A contact header with an array of pin contacts is provided at the far end of the housing to connect with a corresponding contact array disposed in the front end of the memory card. Typically, L-shaped pin contacts are employed in the connector to facilitate connection of each pin to a printed circuit board; one end of each pin extends into the storage space of the connector, while the other end extends downwardly, external to the housing, for soldering to the printed circuit board. 
     Many prior art connector devices employ an ejection mechanism having a slide plate that engages with the memory card, a rotatable lever mounted on the housing and coupled at one end to the slide plate, and a push rod coupled to the other end of the lever. To eject a memory card, the push rod is manually driven toward the contact header. Movement of the push rod toward the contact header is translated through the rotating lever into movement of the slide plate away from the contact header. As the slide plate moves away from the contact header, it engages with the memory card thereby disconnecting the memory card from the array of contacts on the header and urging the memory card backward out of the connector device. 
     Some connector devices have multiple storage decks. For example, U.S. Pat. No. 5,149,276 discloses a connector apparatus having upper and lower storage decks. Each deck has its own array of pin contacts. As is typical of prior art connector devices with multiple storage decks, L-shaped pins are employed in each deck. Thus, the external portions of both sets of pins extend downwardly for connection to a printed circuit board mounted underneath the connector apparatus. Of course, the upper set of contact pins must protrude further from the connector before extending downwardly to the printed circuit board so as to avoid interference with the lower set of contact pins. Each set of pins are connected to the printed circuit board by soldering. 
     Unfortunately, the use of L-shaped pins in each storage deck has proven to be disadvantageous when attempting to solder each set of contact pins to the same printed circuit board. In particular, it has been difficult to employ surface mount techniques to connect each set of contact pins to the circuit board. Consequently, high volume production of printed circuit boards with multiple storage deck connectors is difficult to achieve. 
     Generally, the upper and lower storage decks are separate units and are simply mounted on top of each other to form a dual storage deck apparatus. Unfortunately, because the L-shaped contact pins of the upper deck extend outward, effectively covering the contact pins of the lower deck, surface mount techniques for soldering the respective sets of contact pins to a circuit board are difficult; the contact pins of the upper storage deck prevent easy access to the contact pins of the lower deck. 
     One solution to this problem is to solder the contact pins of the lower deck to the circuit board in a first soldering step prior to mounting the upper storage deck. Once the lower storage deck is secure, the upper storage deck may be mounted on the lower storage deck, and the contact pins of the upper storage deck may be soldered to the circuit board in a second soldering step. Unfortunately, however, the second soldering step can effect the hardened solder joints of the lower contact pins in such a way that stress may occur in the hardened solder joints, in components already attached to the circuit board, and in the circuit board itself. Moreover, if one of the lower contact pins breaks free during the second soldering step, resoldering is extremely difficult since the upper contacts are now in the way. 
     SUMMARY OF THE INVENTION 
     It is accordingly an object of the present invention to provide a multi-storage deck connector apparatus that avoids the disadvantages that result from having to electrically connect the contact pins of each storage deck directly to a main printed circuit board. 
     According to the present invention, a multi-storage deck connector apparatus for memory cards comprises: 
     at least upper and lower frames coupled together in a stacked arrangement, each frame having opposing side rails spaced at an interval substantially equal to the width of a memory card, each frame defining a respective storage deck of the connector apparatus; 
     a first array of contact pins disposed in the upper storage space; 
     a second plurality of contact pins disposed in the lower storage space; 
     a first circuit board to which one of the upper and lower arrays of contact pins is directly electrically connected; 
     a second circuit board to which the other array of contact pins is directly electrically connected; and 
     a vertical connector arranged between the first circuit board and the second circuit board and adapted to electrically connect the first circuit board to the second circuit board, whereby one of the arrays of contact pins is directly electrically connected to the first circuit board and the other array of contact pins is indirectly electrically connected to the first circuit board via the second circuit board and the vertical connector. Preferably, the first and second arrays of contact pins are connected to their respective circuit boards using a surface mount soldering technique. 
     A method for assembling a multi-storage deck connector apparatus to a first printed circuit board in accordance with the present invention comprises the steps of: 
     a) attaching the lower frame to the first printed circuit board; 
     b) soldering to the first printed circuit board (i) the array of contact pins of the header of the lower frame and (ii) the terminals of the header of a vertical connector; 
     c) assembling the upper frame of the connector apparatus to the lower frame; 
     d) fitting a receptacle of the vertical connector over the header of the vertical connector, there being a second printed circuit board electrically connected to the terminals of said receptacle; and 
     e) soldering the array of contact pins of the header of the upper frame to the second printed circuit board, whereby the array of contact pins of the header of the upper frame are indirectly electrically connected to the first printed circuit board via the second printed circuit board and the vertical connector. Prior to performing step (b), predetermined areas of the first printed circuit board are coated with a solder paste. Preferably, the soldering steps (b) and (e) are performed in accordance with a surface mount soldering technique. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view showing a connector apparatus according to one embodiment of the present invention; 
     FIG. 2 is a perspective view showing the connector apparatus together with two circuit boards; and 
     FIG. 3 is a perspective view showing the slide plate of the connector apparatus of FIG.  1 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring to the drawings, wherein like numerals indicate like elements throughout, there is shown in FIGS. 1 and 2, a connector apparatus for memory cards in accordance with a preferred embodiment of the present invention. As used herein, the term “memory card” refers to any plate-like integrated circuit card regardless of function, including those specified by the PCMCIA, JEIDA and JEDEC associations. 
     As shown, the connector apparatus  12  of FIGS. 1 and 2 comprises upper and lower frames  12   a  and  12   b  which are coupled together in a stacked arrangement. Each frame  12   a ,  12   b  defines a respective storage deck  22   a ,  22   b  of the apparatus  12  and comprises a cross member  23   a ,  23   b  and a pair of side rails  13   a ,  13   b  that extend from the cross member and are spaced at an interval substantially equal to a width of a memory card. Preferably, the cross member  23  and side rails  13  of each frame  12   a ,  12   b  form a generally U-shaped structure, one end of each frame  12   a ,  12   b  being open. Upper and lower headers  16   a  and  16   b  are coupled at the other end of each frame  12   a ,  12   b  proximate the respective cross members  23   a ,  23   b . Each header  16   a ,  16   b  carries a respective array of contact pins  64   a ,  64   b . As can be appreciated, additional frames (not shown) can be stacked on top of frames  12   a  and  12   b  to form additional storage decks. 
     Slots  24   a ,  24   b  are formed in the inner surfaces of the respective side rails  13   a ,  13   b  of each frame  12   a ,  12   b  to guide memory cards  20   a  into and out of the respective storage decks  22   a ,  22   b  via the open ends thereof. Alternatively, one hard disc drive (HDD) package  20   b , such as, for example, a type III PCMCIA card, may be stored in the connector device  12 . As shown in FIG. 1, the HDD package  20   b  has a thickness t 2  and comprises a base plate section  20   c , and a housing  20   d  containing the actual hard disk drive (not shown). The housing  20   d  has a width smaller than that of the base plate section  20   c . The base plate section  20   c  has substantially the same width and height as one of the memory cards  20   a.    
     When the HDD package  20   b  is inserted into the connector apparatus  12 , the base plate section  20   c  is guided along the slots  24   b  in the side rails  13   b  of the lower frame  12   b . Due to its thickness t 2 , the HDD package will occupy both the upper and lower storage decks  22   a,b  when fully inserted into the connector apparatus  12 . An I/O socket is disposed in the forward end  20   e  of each memory card  20   a  and the HDD package  20   b  for connecting to the contact pins  64   a,b  of the respective headers  16   a,b.    
     Upper and lower ejecting mechanisms  40   a  and  40   b  are coupled to the upper and lower frames  12   a ,  12   b , respectively. Preferably, the upper and lower ejecting mechanisms  40   a,b  are identical. As shown in FIG. 1, the upper ejecting mechanism  40   a  has a lever  42   a  pivotally supported on the cross member  23   a  of the upper frame  12   a . One end of the lever  42   a  is coupled to a push rod  44   a . The push rod  44   a  is inserted into a guide frame  43   a  mounted on an outer side surface of the upper frame  12   a  and is slidable along the Y direction. The other end of the lever  42   a  has a claw  46   a  which, through an opening  47   a  in the cross member  23   a , engages with a slide plate  48   a  (FIG. 3) as described below. 
     FIG. 3 is a bottom view showing the slide plate  48   a . In the present embodiment, the slide plate  48   a  is disposed below the cross member  23   a  of the upper frame  12   a  and has a substantially U-shaped configuration with a pair of legs  50   a . Each leg  50   a  has a claw  52   a  extending substantially perpendicular thereto. The claws  52   a  of the slide plate  48   a  are guided in corresponding grooves formed in the upper surface of the side rails  13   a  of the upper frame  12   a  proximate the cross member  23   a . The slide plate  48   a  has a pair of hooks  56   a  near its forward end that engage with the forward end  20   e  of a memory card inserted into the upper storage deck  22   a . The slide plate  48   a  has a claw  58   a  at its middle that engages with the claw  46   a  of the lever  42   a.    
     When a memory card, e.g. memory card  20   a , is inserted into the upper deck  22   a , its forward end  20   e  engages with the hooks  56   a  of the slide plate  48   a  causing the slide plate  48   a  to slide toward the header  16   a . As the memory card moves further into the storage deck  12   a , the I/O socket in the forward end  20   e  of the memory card electrically connects to the contact pins  64   a  of the upper header  16   a.    
     To eject the card, the push rod  44   a  is pushed toward the header  16   a  causing the lever  42   a  to pivot about its midpoint such that the claw  46   a  of the lever  42   a  engages with the claw  58   a  of the slide plate  48   a  thereby urging the slide plate  48   a  toward the open end of the upper frame  12   a . As the slide plate  48   a  moves toward the open end of the frame  12   a , the hooks  56   a  of the slide plate  48   a  engage with the forward end  20   e  of the memory card thereby forcing the card backward out of the upper storage deck  22   a.    
     Similar component parts (not shown) of the lower ejecting mechanism  40   b  are arranged between the upper and lower frames  12   a ,  12   b . The lower ejecting mechanism  40   b  operates to eject memory cards from the lower deck  22   b . When, an HDD package  20   b  is inserted in the apparatus  12 , the lower ejecting mechanism  40   b  is used to eject the HDD package. 
     As shown in FIG. 2, the lower frame  12   b  of the dual storage deck apparatus  12  is mounted on a printed circuit board  60  which is omitted in FIG. 1 for convenience of illustration only. Respective interface circuits (not shown) for the upper and lower headers  16   a  and  16   b  may be printed on the printed circuit board  60 . 
     The upper header  16   a  of the connector apparatus  12  has a plurality of L-shaped contact pins  62   a  with upturned solder tails  64   a . According to the present invention, the solder tails  64   a  of upper array of contact pins  62   a  are inserted through corresponding solder holes in a small printed circuit board  66  and are soldered thereto. A receptacle  70  of a surface mount vertical connector  68  is mounted on the lower surface of the small printed circuit board  66 . Terminals  72   a  of the receptacle  70  are soldered to the small printed circuit board  66 . The small printed circuit board  66  connects each terminal  72   a  to a respective one of the solder tails  64   a , in a one-to-one correspondence. Essentially, therefore, each terminal  72   a  is an extension of a respective one of the contact pins  62   a  of the upper header  16   a.    
     A mating header  74  of the face mount vertical connector  68  is mounted on the printed circuit board  60 . Mating terminals  72   b  of the header  74  are soldered to the printed circuit board  60 . Like the upper header  16   a , the lower header  16   b  of the connector apparatus has a plurality of contact pins  62   b . Down-turned solder tails  64   b  of the contact pins  62   b  of the lower header  16   b  are soldered directly to their corresponding connection points on the main printed circuit board  60 . When the upper housing  12   a  is assembled on the lower housing  12   b , as described hereinafter in greater detail, the receptacle  70  and header  74  of the vertical connector  68  are connected together to form an electrical connection between each of the contact pins  62   a  of the upper header  16   a  and corresponding connection points on the main printed circuit board  60 . That is, the small printed circuit board  66  and vertical connector  68  serve to connect each of the contact pins  62   a  of the upper header  16   a  to respective signal traces on the main printed circuit board  60 . Thus, whereas the contact pins  62   b  of the lower header  16   b  are directly connected to the circuit board  60 , the contact pins  62   a  of the upper header  16   a  are indirectly connected to the circuit board  60  via the small circuit board  66  and vertical connector  68 . 
     A space S is defined between the lower header  16   b  of the connector apparatus and the header  74  of the vertical connector  68 . Various circuit components may be mounted to the printed circuit board in space S. 
     According to a method of the present invention, the connector apparatus is assembled to the printed circuit board  60  as follows: 
     (i) predetermined areas on the printed circuit board  60  are coated with a solder paste; 
     (ii) the lower housing  12   b , lower header  16   b  and vertical connector header  74 , but not the lower ejecting mechanism  40   b , are arranged on the printed circuit board  60  (these component parts can be located manually or by a mechanical means); 
     (iii) the contact pins  62   b  of the lower header  16   b  and the terminals of the header  74  of the vertical connector  68  are then connected to the printed circuit board  60  by soldering; 
     (iv) the lower ejecting mechanism  40   b  is then fixed to the lower housing frame  12   b  with suitable hardware; 
     (v) the upper housing  12   a  and the upper ejecting mechanism  40   a  are then assembled on the lower housing  12   b  (the upper and lower ejecting mechanisms  40   a  and  40   b  may be connected by a proper screw/nut combination or a locking pin); 
     (vi) the receptacle  70  of the vertical connector  68 , which is pre-mounted on a small circuit board  66 , is then fitted over the header  74 ; and finally, 
     (vii) the solder tails  64   a  of the upper header  16   a  are soldered to the small printed circuit board  66 . 
     As can be appreciated, the lower header  16   b  is directly connected to the printed circuit board  60  and the upper header  16   a  is indirectly connected to the printed circuit board  60  via the small printed circuit board  66  and vertical connector  68 . Thus, the upper and lower headers  16   a  and  16   b  are both connected to the circuit board  60  without the disadvantages that result from having to directly solder both headers to that circuit board  60 .