Abstract:
The invention concerns an input/output connector ( 10 ) comprising a first electrically insulating part ( 1 ), including at least a fixing element ( 2, 4 ) and at least a contact strip, and a second part ( 50 ) acting as housing, which partly covers the first part ( 1 ), the planar connecting surface ( 5 ) of the contact rib ( 7 ) being located substantially in the same plane as the lower surface ( 9 ) of the fixing element ( 2, 4 ), such that said plane defines the plane for fixing the connector. Said connector can further comprise a power contact. The method for making such a connector consists in metallizing the plastic material to form the contact strip on the first part.

Description:
FIELD OF THE INVENTION 
     The invention concerns an input/output connector, particularly for surface mounting on a printed circuit card, the connector comprising a first electrically insulating part, which has at least one fixing element and at least one contact, and a second part, which serves as housing and partially covers the first part, according to the preamble of claim  1 . In addition, the invention concerns a process a process for manufacturing connectors that can be surface mounted, according to claim  14 . 
     BACKGROUND OF THE INVENTION 
     Such connectors are preferably used in portable communication devices, such as mobile phones or analogous devices. Usually, such devices are very small and easy to handle, so that there is little space for input/output connectors (which are also referred to as I/O connectors), which, for this reason, are surface mounted on a printed circuit card according to the SMD (surface mounted device) technique. Such connectors constitute mechanical interfaces for the connection of various peripheral devices, such as, for example, data transmission modems. The connectors, the dimensions of which are very small, have to be positioned precisely during mounting on the printed circuit card. In addition, they have to withstand strong mechanical demands on the life of the mobile phone and, if need be, they have to establish a good electrical connection between the connector and a complementary connector. 
     It has thus turned out that the demands pointed out above can be well satisfied if the connection side of the connector coincides essentially with the plane of the printed circuit card. In addition, it is indispensable that the fixing surface of the connector be reproducible. 
     Known from the document U.S. Pat. No. 6,000,953 is an I/O connector that uses, for the precise positioning of the connector, two L-shaped, removable holding clips, which are placed on the sides and at each end of which a projection is cut out by stamping. During the mounting or positioning of it, only these two projections make contact with the printed circuit card, so that the connector can be mounted in place in a way that permits pivoting. During the pivoting, the lowest contact pin of the connector is the first to reach the surface of the card and, together with the projections, makes up a tripod that defines the connection face of the connector. 
     Here, it is particularly disadvantageous that, on account of the flexibility of the connector contact pins, there is a longitudinal inclination with respect to the card, which is sometimes large and sometimes small. In addition, the reproducibility of this connection face makes it necessary to have contact plugs that are very precise in terms of form and length. Very narrow tolerance ranges also have to be observed for the lengthwise positioning of the pins in the housing. This inevitably increases the production costs of such a connector. In addition, it needs to be mentioned that the heights of the projections, obtained by stamping, are subject to great variation. In the prior art, this imprecision is not noteworthy owing to the fact that the heights of the projections are small in relation to their spacing. However, these variations do become noticeable if narrow I/O connectors are involved (for example, connectors that support only a few connections), so that, as the longitudinal inclination increases, a lateral wiggle becomes noticeable. The holding clips, which would also be poorly or falsely mounted laterally, also reinforce this effect, this being able to arise, for example, from impurities that have slipped between the clip and the housing. 
     In addition, owing to the fact that the connector comprises several basic pieces, such as the two removable holding clips, the contact pins enclosed in the housing, the housing itself, and locking hooks, a large number of manufacturing steps are required and this also increases the production costs. In addition, these narrow contact pins are not designed for large electrical powers. 
     SUMMARY OF THE INVENTION 
     The object of the invention is to propose an input/output connector for surface mounting on a printed circuit card, the connector comprising a first electrically insulating part, which has at least one fixing element having a planar face and at least one contact lead with a planar connection face, and a second part, which serves as housing and partially covers the first part and which has a connection face that is reproducible in a very precise way, it being possible to position this connector in a simple way on a printed circuit card. 
     This problem is solved by the fact that the planar connection face of the contact lead is situated essentially in the same plane as the bottom planar face of the fixing element, this plane defining the plane for fixing the connector. Moreover, the fact that the contact lead corresponds to a metallization deposited on an insulating zone of the first part, which is not covered by the second part, also contributes to the solution of this problem. 
     An advantageous mounting of the invention is obtained by the fact that the first part is made up of a piece formed by a single injection molding and that the second part is partially molded on above the first part. 
     It is thus particularly advantageous that the first part, together with its elements, is made up of a single piece. After the molding, there occurs no possibility of movement or of shifting forward or backward between the elements of the first part. The sole precaution consists in precisely milling the casting mold of the first part, namely, here, the injection molds. With the help of computer numerically controlled (CNC) machines, this does not pose any problem. The second part fills in the empty spaces of the first part and, owing to this, reinforces it, this creating a sturdy mechanical unit (connector). 
     Another advantageous mode of realization of the invention is that according to which the first part can have, on each of the two sides of the connector, a fixing element, in each of which centering holes can be arranged. 
     Preferably, in accordance with a special mode of realization of the invention, the connector includes the means for supporting strong electrical currents by, for example, having at least one power module for the transmission of high electrical powers. 
     In accordance with this special mode of realization of the invention, the power module consists of a metallic center contact, a metallic spring contact, and a holding contact, these contacts being capable of being connected electrically to a printed circuit card by means of bands of metallized synthetic material. 
     The connector in accordance with the invention consists of a first electrically insulating part, which has at least one fixing element and at least one electrical contact, and a second part, which serves as housing and partially covers the first part. The horizontally extending, planar connection face of the rigid contact is situated essentially in the same plane as the bottom planar face of the fixing element, this plane defining the plane for fixing the connector. 
     The connector comprises solely two parts and possibly a power module. It is only the first part that determines, by means of an undetachable fixing element and an undetachable contact having the connection surface, the plane for fixing the connector. A special feature of the invention lies in the fact that the connector does not require any additional mounting clip or hook to ensure the positioning and the fixation. Above all, it is necessary to bring out the fact that, when the connector has several contacts, all the fixing surfaces are situated in exclusively one plane. 
     Other advantageous modes of realization of the invention are characterized by the fact that the power module consists of a median metallic contact, an elastic metallic contact, and a holding contact, these contacts being capable of being connected electrically to a printed circuit card by means of bands of metallized synthetic material and by the fact that the two bands of synthetic material, extending over the back face of the connector and belonging to the first part, become separated connection surfaces that are situated in the same plane as the connection faces of the rigid contacts. 
     A power module that is realized in this way can be used to charge the device connected to it, a good electrical connection being ensured. 
     Another mode of realization of the invention is characterized by the fact that the center contact of elongated form, corresponding to a symmetry of rotation, has a smaller diameter in the zone in front than in the zone in back, which has at least one section of spherical form, projecting toward the outside in order to ensure the electrical and mechanical connection of the center contact to the first band or lead. 
     Such a center contact prevents, on the one hand, the scraping of a metallized surface and, on the other hand, thus ensures, all else notwithstanding, a good mechanical mounting. 
     Another object of the invention is to propose a process for manufacturing a connector capable of surface mounting, this process involving low production costs. 
     This object is attained by a process for manufacturing a connector that can be surface mounted in which the following manufacturing steps are involved. First of all, the first part is injection-molded. This is followed by chemical activation of the surface of the first part and then by filling in injection molding by compression of the first part in the injection mold of the second part. Now, the second part is partially molded on above the first part. Afterwards, the connector is metallized, the metal adhering only to the surface of the first part that is left exposed. Finally, in accordance with the chosen variant of the invention, metallic elements of the power module are possibly introduced into their corresponding chambers. 
     Thus, for the injection molding of the second part, the same thermoplastic material is used as for the injection molding of the first part. A special feature of the invention consists in the activation of the surface of the first part. Above all, this makes it possible to deposit the metal and to cause it to adhere to the synthetic material, such as a thermoplastic material. The first part is introduced into the injection mold of the second part and is subjected to filling in injection molding by compression, so that the first part, during the second pass, is not moved. After this, the second part that is formed plays the role of a sturdy, electrically insulating housing, owing to the fact that the voids and the intermediate spaces of the first part are filled. During the metallization, the second part acts as a mask. On the second part itself, no trace of adhering metal remains owing to the fact that, in general, the synthetic material chemically bonds poorly to the metal. By contrast, on the exposed, activated surface of the first part, a deposition of metal is preferably carried out. Simultaneously, the second part brings about the mutual separation of the different metallized zones of the first part, so that the latter are not connected to one another electrically. Thus, there occurs the formation of dedicated conducting zones that can be used as contacts. These metallic zones thus have an underlying support that is stiff and rigid, specifically the first part, which undergoes deformation poorly or hardly at all under the effect of pressure. It is thus particularly advantageous that, for such connectors manufactured in accordance with the invention, no contact plug is used. Contact pins or contact springs are used solely for the power module. It is therefore possible to combine the advantages of the two technologies without increasing the costs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A preferred example of realization of the connector in accordance with the invention will be described in detail below with reference to the schematic drawing. Shown in the drawing are the following: 
         FIG. 1 : a view from above in perspective of the connector in accordance with the invention; 
         FIG. 2 : a view from below in perspective of the connector in accordance with the invention, taken from  FIG. 1 ; 
         FIG. 3 : a cross section along the plane B—B of  FIG. 1 ; 
         FIG. 4 : a cross section along the plane A—A of  FIG. 1 ; 
         FIG. 5 : a representation of a small zone of the first part without the second part added from below by mold casting; 
         FIG. 6 : a front view of a special mode of realization of the connector in accordance with the invention; 
         FIG. 7 : a view from below in perspective of a special mode of realization of the connector of  FIG. 6 ; 
         FIG. 8 : a section view along the line F—F of  FIG. 6 ; and 
         FIG. 9 : a section view along the line G—G of  FIG. 6 . 
     
    
    
       FIGS. 1 and 2  represent the input/output connector in accordance with the invention as viewed from above and viewed from below, both in perspective. The connector is preferably cast in two passes. In the course of a first pass, a first part  1 , such as illustrated in  FIG. 5 , is formed and, in the course of a second pass, it is the second part  50 , partially covering the first part  1 , that is made. In order to obtain a better understanding, the elements of the first part are marked by the reference characters  1  to  49  and the elements of the second part by the reference characters starting with  50 . Essentially visible in the view from above in  FIG. 1  is the second part  50  of rectangular shape. 
     DETAILED DESCRIPTION 
     The first part  1  and the second part  50  are preferably made of an insulating thermoplastic material. The connector includes at least one contact lead  3 . This contact lead  3  is obtained by metallization on the surface of the first part  1 . The metallization is carried out solely on the zones of the first part that have been activated beforehand and have been made capable of fixing a layer of metal. 
     This metallized surface includes at least one portion presented in a connection plane  5  that is essentially identical to a plane in which the fixing elements  2  and  4  are presented in the first part  1 . The metallization obtained is of very small thickness and the molds that are used to form the first part  1  are designed in such a way that the subsequent addition of the metallization makes it possible to guarantee a coplanarity of the connection plane  5  with the plane of the fixing elements  2  and  4 . For example, the plane of the fixing elements corresponds to the plane of the bottom faces  9  of these fixing elements  2  and  4 . The bottom faces  9  and the faces presented in the connection plane  5  are situated in a single plane. At most, a divergence of 50 microns may exist between the plane of the bottom face  9  and the connection plane  5 . 
     The first part  1  includes the contact ribs  7 . A contact rib  7  is furnished so as to have, at its periphery, a contact lead such as  3 . The fixing elements  2  and  4 , together with their centering holes  6  and  8 , respectively, are formed in one piece with the contact rib  7  during the molding of the first part  1 . In order to obtain the desired coplanarity, the bottom faces  9  of the fixing elements  2  and  4 , as well as the connection faces  5 , are placed against a flat base of the injection mold of the second part. This thus guarantees that the molding on operation will not affect this coplanarity in that no deposition on these faces will take place in the course of this second pass. 
     The molding on of the second part  50  is carried out in such a way that the latter does not completely cover the first part  1 . The activated zones of the first part  1  remain accessible and are thus capable of being metallized after the molding of the second part  50 . 
     The second part  50  has a body of rectangular shape that is elongated on its two short sides by two projections  57  and  58 . Formed in the center of each projection  57 ,  58  is a hole  64  and  65 , respectively. Visible on a lower edge  59  of a top face of the body are three windows  61 ,  62 , and  63  of rectangular shape. The holes  64 ,  65 , as well as the windows  61  to  63 , are produced by means of holding posts, coming from above, which press on the first part  1  at, for example, the level of the face  22 , which is already molded so as to fix it in the injection mode of the second part  50 . These holding posts permit the formation of the windows and holes. Indeed, at these places, no thermoplastic substance can be molded owing to this fact. 
     The fixing elements  2  and  4  of the first part  1  extend on the outside on these same short sides of the second part  50  in superposition with the projections  57  and  58 . The centering holes  6  and  8  of the fixing elements  2  and  4  can be used for the positioning of the connector on the printed circuit card. 
     The connector is preferably organized according to a modular structure. It includes at least one contact module. A contact module includes at least one contact rib, such as  7 , which is an electrical conductor. In a special first mode of realization, in  FIG. 2 , the first part  1  of the connector includes three contact modules. When the front of the connector is viewed from left to right, the first part  1  has a first contact module  14  having two contact ribs  7 . There is then a second contact module  15  having nine contact ribs  7 . Finally, there is a third contact module  16  having one contact rib  7 . 
     The modules  14  to  16  are set in a frame  71  formed from a single piece on a fixing front. The contact ribs are arranged parallel to one another and include at least one second portion  11  that is perpendicular in relation to the direction of plugging. 
       FIG. 3  represents a section along the plane B—B of the connector of  FIG. 1 . The plane of the section B—B extends parallel to the direction of plugging and cuts a contact rib  7  in the longitudinal direction. The hatched zone, the hatch marks of which go toward the left in the upper part and toward the right in the lower part, indicate the second part  50 . The frame  71  is visible on the exterior front of the connector  10  in the upper part and in the lower part. A receiving chamber  32 , provided for receiving a contact of a complementary connector, is situated in an intermediate position. The hatched zone, the hatch marks of which go toward the left in the lower part and toward the right in the upper part, indicates the contact rib  7 , which is an element of the first part  1 . The bottom and front surfaces (at the left in the figure) of the rib  7  are not covered by the second part, so that the metallic contact leads  3  can be deposited there. These metallic leads  3  form the first portion, parallel to the bottom face of the connector, to be applied against a printed circuit card with which it can be connected. This first portion corresponds to the portion of metallized surface presented in the connection plane  5 . 
     The metallic deposit is made over the entire length of the rib  7  in such a way as to form the contact lead  3 . It is deposited on the surface of the front part of the contact,  11 , essentially extending vertically on the figure, and on the surface of the back part of the contact,  5 , essentially extending horizontally in the figure, which are provided for making the respective electrical contacts with the associated peripheral devices or complementary connectors and with the printed circuit card. The contact surfaces  5  and  11  are connected to one another by another portion of the contact lead  3 . 
     It should be noted that the metallic deposit does not result in an increased thickness that modifies the dimensions of the rib  7 . The contact is made up of an electrically conducting contact lead  3 , which is applied to the uncovered surface of the contact rib  7  belonging to the first part  1 , the zone, opposite to the exterior front  10 , of the contact lead  3  forming the electrical connection surface  5  for the printed circuit card, and the zone, facing the exterior front  10 , of the contact lead  3  forming the surface of electrical connection  11  for the associated peripheral device. 
     The ends  23  of the ribs  7  emerge from a lower part of a back face  67  of the body. Visible on the right in  FIG. 4  is the end  23  of the rib  7 , which passes through the back face  67  of the part  50 . 
       FIG. 4  represents a section along the plane A—A of the connector of  FIG. 1 . The plane of the section A—A extends parallel to the direction of plugging, passes through a window  61 , and then cuts at least one connecting element of the connector. Indicated in  FIG. 4  by way of hatch marks are two connecting elements, a lower one and an upper one,  12  and  13 , respectively, which make it possible to isolate the conducting leads, such as  3 , and to connect the modules to one another. These connecting elements  12  and  13  serve as inserts between the ribs, such as  7 . The hatch marks have the same meaning as in  FIG. 3 . The window  61  is visible on the right and on the left in  FIG. 4 . The upper connecting element  13 , which is situated below, is fixed in the injection mold during the second pass by a holding post pressing downward from above. The post thus arrives at the upper edge  22  of the upper connecting element  13 . 
       FIG. 5  represents the first part directly after the first injection molding and only shows the first contact module  14 . This module has two ribs  7  that extend parallel to each other. They are joined together mechanically by the two connecting elements  12 ,  13 . The intermediate space  28  lying between them is filled in during the second molding pass by the material of the second part  50 , which thus forms the shoulders  55 . 
     In the mode of realization presented, the connector includes at least one means of locking. In  FIG. 2 , it includes two locking modules, a first module  51  and a second module  52 . One locking module corresponds here to a seat  70  that is machined, or molded, in the second part  50 , intended for locking hooks of the complementary connector, which is not represented. The second locking module  52  is formed identically to the first module  51  in the second part  50 . The two locking modules  51  and  52  are distributed among the contact modules, preferably on either side of the second contact module  15 . 
     In a variant presented through  FIGS. 6 to 9 , the contact module  14  is replaced by a power module  14 , which does not include a rib, but does have a center contact  81 , a spring contact  82 , and a holding contact  83 . In this variant in accordance with a special second mode of realization of the invention, the connector includes such a power module  14  to which is linked the first locking module  51 . Provided afterwards is the second contact module  15 , such as described in the preceding, furnished with nine contact ribs  7 . The complementary second locking module  52 , which, as presented here, evidently forms a cavity with a form different from that of the first module  51 , comes next. Finally, the third contact module  16 , itself furnished with two contact ribs  7 , establishes the connection. In this variant as well, the modules  14  to  16  are set in the frame  71  formed in one piece on the front of the connector. The differences in form between the two locking modules  51  and  52  thus provide the connector with a means of proper alignment. 
     In this variant, the power module  14 , to be described in more detail, will be attached. In order to realize such a connector, it is molded in two passes and the metallic elements, namely, the center contact  81 , the spring contact  82 , and the holding contact  83 , are introduced into their corresponding chamber in the course of a final stage, after the metallization of the contact ribs, such as  7 , has taken place. For reason of better understanding, the elements of the power module are represented by the reference characters numbered starting with  80 . 
       FIG. 7  shows the connector viewed from the back and viewed from below. Here, the ribs  7  extend parallel and are separated by the clearly visible shoulders  55 . In  FIG. 7 , two connecting leads  5 ′,  5 ″ are arranged parallel to the contact ribs  7 . They are elongated by the leads made of metallized synthetic material,  84 ,  85 , in such a way that the contacts  81 ,  82  of the power module  14  are connected electrically to those connection faces  5 ′,  5 ″. 
     In a back face  14   b  of the power module  14 , on the right in  FIGS. 8 and 9 , are arranged a receiving chamber  92  for the spring contact  82 , a receiving chamber  91  for the center contact  81 , and a receiving chamber  93  for the holding contact  83 . 
     Just as the ends  23  of the ribs  7  emerge in a lower part of the back face  67  of the body  56 , the connecting leads  5 ′,  5 ″ also have ends emerging in the same way from the back face  67 , all being aligned in relation to their corresponding connection contacts of a printed circuit card with which they can be connected. This makes it possible to obtain a secure and rapid brazing of the faces  5 ,  5 ′,  5 ″ with these contacts in a brazing oven by fusion. 
     On one lateral face  14   a  of the module  14 , the first lead  84  of the center contact  81  extends first horizontally, then vertically, then horizontally on the back face  14   b  of the module  14 , before the lead  84  disappears in the chamber  91 . The second lead  85  of the spring contact  87  extends horizontally, then vertically on the lateral face  14   a,  before the second lead  85 , passing through a window  87  arranged in the module  14 , arrives in the chamber  92  of the spring contact  82 . 
       FIG. 8  represents a section along the line F—F of the connector of  FIG. 6 . This section passes exactly through the center of the power module  14 . On this section, from top to bottom, is seen the holding contact  83 , the center contact  81 , and the second tongue  82   b  of the spring contact  82 . The receiving chamber  93  of the holding contact  83  is visible in the upper third. This has a catch  83   a  turned downward that can block the complementary connector, which is not shown. In the middle third, the center contact  81  extends horizontally and, in the back zone  81   b,  it is provided with three sections  81   a,    81   b,  and  81   c.  The leftmost section of these comes to be wedged in the second part  50 . At the right and at the side is situated a block  88  that arises from the first pass. The lower edge is metallized and constitutes the end of the second lead  85 , which is connected electrically to the connection face  5 ″. The lower cylindrical zone of the block  88  is also metallized and constitutes the end of the first lead  84 , which is connected to the connection face  5 ′. 
     The center contact  81  has an elongated form, corresponding to a symmetry of rotation, and has a smaller diameter in the zone in front  81   a  than in the zone in back  81   b,  which has at least one section  81   c  of spherical form, projecting toward the outside in order to ensure the electrical and mechanical connection of the center contact to the first band or lead  84 . 
     Thus, the two right sections  81   c  are wedged in the interior of the block  88 , causing them to establish contact with the first band or lead  84 . The sections  81   c  of spherical form prevent a scraping of the metallic surface of the block  88  from occuring during the insertion of the center contact  81  into the chamber  91 . 
     The spring contact  82  has two tongues  82   a  and  82   b,  the first tongue  82   a  establishing contact with the second band  85  and the second tongue  82   b  penetrating into the receiving chamber  78  of the complementary connector. 
       FIG. 9  represents a section along the line G—G of the connector of  FIG. 6 . The block  88  and the first tongue  82   a  coming from the spring contact  82  are thus represented in section. In the upper third is seen the holding contact passing through a window. Drawn below as a broken line is the center contact. The L-shaped block  88  that is present at this place emerges from the back face  14   b.  The first lead  84  is thus visible there in the form of a dark vertical line. The bottom face of the block  88  is metallized and constitutes, as already mentioned, the end of the second lead  85  with which the first tongue  82   a  enters into mechanical contact. The spring contact  82  is thus connected electrically to the connection face  5 ″.