Patent Publication Number: US-6666717-B1

Title: Structure of horizontal type DIMM connector for dense arrangement

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to horizontal type DIMM (Dual In-line Memory Module) connectors, and particularly to dense arrangement of multiple horizontal type DIMM connectors. 
     2. The Related Art 
     U.S. Pat. No. 5,964,606 having the same inventor and the same assignee with the invention, discloses structures of identical slanted type DIMM connectors for dense arrangement. Understandably, the slanted type DIMM connector is to replace the vertical type DIMM connector, e.g., U.S. Pat. No. U.S. Pat. No. 6,227,887, for reducing the height/profile of the module/connector assembly. Anyhow, under some situations, the slanted type DIMM connectors are still unable to meet the strict low profile requirements because the DIMM module, which is inserted into the DIMM connector, obliquely upwardly extends from the DIMM connector thereby still occupying significant space in the vertical direction. Thus, the horizontal type DIMM connectors were provided to meet such requirements. Such conventional horizontal type DIMM connector is only for single use without concerns about usage of more than one horizontal type DIMM connectors. The invention is to provide a pair of horizontal type DIMM connectors which are adapted to be densely arranged in a front-to-back direction to reach the minimum height/profile in the vertical direction, the minimum space in the horizontal direction, and free release from the mother board for each individual horizontal type DIMM connector without obstacle during a de-soldering/rework process as pursued in the aforementioned U.S. Pat. No. 5,964,606. 
     SUMMARY OF THE INVENTION 
     According to an aspect of the invention, a first horizontal type DIMM connector includes a first insulative housing defining a first slot with a plurality of first contacts by two sides of the first slot. A pair of first piers extend forwardly from two opposite ends of the first housing, respectively. A pair of ejectors are horizontally pivotally mounted on the pair of first piers, respectively. A second horizontal type DIMM connector includes a second insulative housing defining a second slot with a plurality of second contacts by two sides of the second slot. A pair of second piers extends forwardly from two opposite ends of the first housing. A pair of ejectors are horizontally pivotally mounted on the pair of second piers, respectively. The second housing is positioned at the rear upper position with regard to the first housing. 
     The bottom face of the second housing is spaced from the upper face of the first housing with a distance so as not to have the module inserted into the second slot interfere with either the first housing or another module inserted into the first housing. 
     The rear portion of the first housing opposite to the first pier defines a cutout which is dimensioned, along the lengthwise direction of the first and second housings, larger than the front end of the second pier, and along the front-to-back direction close to the bottom of the ejector of the first connector, so that the front end of the second pier is structurally located above while being able to be compliantly vertically receiveably projected within said cutout when said second connector is densely/closely positioned behind the first connector. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a pair of connectors without showing ejectors and contacts thereof according to the invention. 
     FIG. 2 is a perspective view of the first connector of FIG.  1 . 
     FIG. 3 is another perspective view of the first connector of FIG. 1 without showing the board locks thereof. 
     FIG. 4 is a partially enlarged perspective view of the first connector of FIG.  1 . 
     FIG. 5 is a perspective view of the first connector of FIG. 1 with the inserted DIMM module therein. 
     FIG. 6 is a side view of the pair of connectors of FIG. 1 without showing the board locks thereof. 
     FIG. 7 is a partially enlarged perspective view of the first connector according to another embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS 
     References will now be in detail to the preferred embodiments of the invention. While the present invention has been described in with reference to the specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications to the present invention can be made to the preferred embodiments by those skilled in the art without departing from the true spirit and scope of the invention as defined by appended claims. 
     It will be noted here that for a better understanding, most of like components are designated by like reference numerals throughout the various figures in the embodiments. Attention is directed to FIGS. 1-6 wherein a first horizontal type DIMM connector  10  includes a first insulative housing  12  with an elongated body defining a first central slot  14  with a plurality of first contacts  16  by two sides of the first central  14 . 
     A pair of first piers  18  forwardly extend from two opposite ends of the first housing  12 , respectively. A pair of first ejectors  20  are pivotally mounted on the pair of first piers  18 , respectively. Three first standoffs  22  are respectively located on a bottom face  24  of the first housing  12  for raising up the first housing  12  so that it is easy to assemble the DIMM module  100  into the first central slot  14  of the first connector  10  without interference with the components of the mother board (not shown) on which the first connector is mounted. 
     The board locks  26  and the posts  28  are optionally extend downwardly from the first standoffs  22  for retaining the first connector  10  on the mother board (not shown). Two spacer  30  are provided on a rear portion of the first housing  12  for aligning tails of the first contacts  16 . 
     A second connector  40  is located around a rear upper portion of the first connector  10 . The second connector  40  includes a second insulative housing  42  with an elongated body defining a second central slot  44  with a plurality of second contacts  46  by two sides of the second central slot  44 . 
     A pair of second piers  48  forwardly extend from two opposite ends of the second housing  42 , respectively. A pair of second ejectors  50  are pivotally mounted on the pair of second piers  48 . Three second standoffs  52  are respectively located on a bottom face  54  of the second housing  42  for raising up the second housing  42 . The second standoffs  52  is higher than the first standoffs  22  so that it is easy to assembly another DIMM module  100  into the second central slot  44  of the second connector  40  without interference with either the first housing  12  or the associated DIMM module  100  received in the first central slot  14 . The second connector  30  also includes structures of the posts/board locks, and the spacers, which perform the similar functions as those in the first connector  10 . 
     The first housing  12  defines in the rear portion a pair of cutouts  32  opposite to the first pair of piers  18  in a front-to-back direction. The cutout  32  is dimensioned to be larger than the front end of the corresponding second pier  48  in a lengthwise direction of the first housing  12  and the second housing  42 . Also, the cutout  32  is recessed close to the bottom of the first ejector  20  in a front-to-back direction. Under this situation, the second connector  40  is able to be located behind the first connector  10  as close as possible to have the front end  49  of the second pier  48  structurally located above while being compliantly vertically receivebly projected within the corresponding cutout  32  without interference. Referring to FIGS. 1 and 6, the surface  34  beside the cutout  32  is located in front of the edge  491  of the front end  49  of the second pier  48  along the front-to-back direction, and the surface  36  beside the cutout  32  is located more inwardly in comparison with the inner edge  492  of the front end  49  of the second pier  48 . At the same time, the bottom face  54  of the second housing  42  is spaced from the top face  38  of the first housing  12  with a distance so as to have the module  100  inserted therein will not interfere with either the first housing  12  or the module  100  inserted in the first housing  12 . 
     It is noted that in this embodiment, both the first connector  10  and the second connector  40  are not identical while sharing most same portions for saving molding cost. In other words, the differences may only include heights of the standoffs and the tail lengths of the contacts. It is also noted that as mentioned only one of the board lock  26  and the post  28  may be required as shown in FIG. 7 wherein the post  28  and a portion of the associated standoffs  22  are removed. 
     Similar to the aforementioned U.S. Pat. No. 5,964,606, the first connector  10  and the second connector  40  can be densely/closely arranged together in a front-to-back direction while the first connector  10  may be removed from the mother board for rework without being disturbing the second connector  40  thereabouts. Understandably, the ejectors  50  of the second connector  40  should be in an open position during removal of the first connector  10 . Different from the slanted type DIMM connectors aforementioned U.S. Pat. No. 5,964,606, in the invention the first connector  10  and the second connector  40  are not identical with each other and positioned at two different levels while such slanted DIMM connectors are identical with each other and essentially located at the same level. 
     While the present invention has been described with reference to specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications to the present invention can be made to the preferred embodiments by those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claim. 
     Therefore, person of ordinary skill in this field are to understand that all such equivalent structures are to be included within the scope of the following claims.