Abstract:
An electrical connector for contacting a meting connector is proposed which has a locking device and includes a locking mechanism by means of a tiltable locking latch. The spring-loaded unlocking mechanism is triggered by pulling on a pull tab and constitutes a secure locking connection between the electrical connector and the mating connector.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a locking device for an electrical connector comprising a two-part shell with a cable side for electrical cables and a connecting side in form of a printed circuit board with electrical contacts for directly contacting a mating connector, and a locking latch, in which the electrical connector is automatically locked with the mating connector when it is pushed into the mating connector. 
         [0002]    Locking devices of this type are required in electrical connectors which are joined to shield mating connectors, so-called cages. These connectors, which are also known as SFPs, are used to transmit signals with high data rates such as, for example, in an Ethernet. These connectors are used for two-core copper wires but are also designed for electro-optical transducers, suitable for fibre-optic cables. 
         [0003]    A number of locking mechanisms for such connectors are already known from the prior art which effect the locking and unlocking of the connectors to and from the said cages in many different ways. An optical transducer module with a similar structure is known from U.S. Pat. No. 7,507,111 which can be unlocked by means of a rotatable lever. The small moving parts of the locking mechanism are here situated on the outside and are freely accessible, as a result of which they are not protected from damage and dirt. 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    The object of the present invention is to provide an SFP connector with an unproblematic locking and unlocking mechanism which can be easily manipulated. 
         [0005]    This object is achieved by the locking device wherein inside the sliding element a locking latch is arranged, wherein the sliding element is arranged inside the two-part shell for a displacement of a certain distance, wherein the locking latch is mounted rotatably inside a mount of the bottom shell, and wherein a hook on the locking latch performs a short lifting movement when the sliding element is displaced axially, so that an unlocking or locking action with the correspondingly provided mating connector results. 
         [0006]    Advantageous embodiments of the invention are given in the subclaims. 
         [0007]    The invention relates to a shielded electrical connector for high-frequency data transmissions in a Gigabit Ethernet. These connectors have an extremely slim design, both glass fibres and copper wires being provided as the transmission medium. The version described here uses passive copper wires which, compared with the fibre-optic versions, have the advantage of low power consumption. However, the proposed locking device can also be readily applied to an SFP connector which takes the form of an electro-optical transducer. 
         [0008]    The connecting side of this so-called SFP connector (SFP=Small Form-Factor Pluggable) has a printed circuit board with contact surfaces for contacting corresponding contacts of a mating connector. The design and dimensions of the connecting side of the connector shell are here provided with standard dimensions. 
         [0009]    The connector shells are metallically shielding and equipped with an unlocking mechanism which can be actuated by means of a pull tab provided on the cable side. 
         [0010]    A connector of this type is joined to a so-called cage, a shielded mating connector, which as a rule is in turn installed directly on printed circuit boards inside a shell for switches, routers or bus adapters—in other words, in equipment used in an Ethernet. The connectors can thereby be pushed into corresponding openings in the shell and force-latched there when they are pushed into the mating connector. 
         [0011]    In addition, a spring-loaded unlocking mechanism is provided with a pull tab for unlocking the mating connector. It is here particularly advantageous that the locking apparatus is, in contrast to the prior art, arranged inside the connector shell so that the parts which would otherwise be situated on the outside of the locking mechanism cannot be moved or damaged. 
         [0012]    The cable connection of the individual signal wires is not described in detail as this does not appear to be relevant here. It is sufficient to say that the individual strands are arranged such that they are combined, cast as a block and contact the printed circuit board. The contact tracks which stand out on the printed circuit board on the connecting side thereby make contact with corresponding electrical contacts of a mating connector. 
         [0013]    The connector, which is here formed from two parts, a bottom shell and a top shell, and has a printed circuit board arranged inside for transmitting signals, advantageously hooked in by means of a mechanism formed on the connecting side, is joined together and is screwed together by two screws. 
         [0014]    The locking mechanism situated on the inside of the connector essentially consists of a locking latch and a sliding element. A pull tab is attached to the sliding element on the cable side, by means of which the sliding element can be moved counter to the plug-in direction, this movement being reversible by springs. 
         [0015]    In addition to the sliding element, the locking mechanism also has a tiltable locking latch. The latter locks the connector to the mating connector on its outside. The axial movement of the sliding element is transmitted to the locking latch by means of two guiding pins which are each guided in a forked guide of the locking latch. 
         [0016]    The locking latch is a T-shaped element and, below the upper transverse region, has an axle mount extending parallel to the transverse region and through which an axle is guided, the axle being retained in an axle bore of the shell. This mounting of the locking latch ensures that the locking latch can rotate freely in the shell. 
         [0017]    The forked guides of the locking latch are provided at the outer ends of the transverse region of the T-shape. They are arranged at an angle directed towards the inside of the connector, with respect to the axial movement of the sliding element, and form a first lever part of the locking latch. As a result of this arrangement of the forked guides, the locking latch is rotated about the axle by a certain angle when the sliding element is moved axially by means of the first lever part. 
         [0018]    The rotation of the locking latch is transmitted to a second lever part which is formed by the elongated region of the T-shape. A hook is provided on the outer surface of the second lever part for latching in a corresponding recess in the mating connector. Rotation of the locking latch causes the hook to make a short lifting movement into the connector shell and releases the locking connection to the mating connector. 
         [0019]    The locking connection is thus released by a pulling movement on the pull tab counter to the plug-in direction and the connector can be removed from the mating connector. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         [0020]    An exemplary embodiment of the invention is explained in more detail below and illustrated in the drawings, in which: 
           [0021]      FIG. 1  shows a connector according to the invention with a mating connector, 
           [0022]      FIG. 2  shows an exploded view of the connector, 
           [0023]      FIG. 3   a  shows the inside of a single bottom shell, 
           [0024]      FIG. 3   b  shows a detailed view from  FIG. 3   a,    
           [0025]      FIG. 4   a  shows the outside of the bottom shell from  FIG. 3   a,    
           [0026]      FIG. 4   b  shows a detailed view from  FIG. 4   a,    
           [0027]      FIG. 5   a  shows the inside of a single top shell, 
           [0028]      FIG. 5   b  shows a detailed view from  FIG. 5   a,    
           [0029]      FIG. 6  shows a single locking latch, 
           [0030]      FIG. 7   a  shows a single sliding element from the cable connection direction, 
           [0031]      FIG. 7   b  shows the sliding element from  FIG. 7   a  from the plug-in direction, 
           [0032]      FIG. 8   a  shows a partially cutaway connector in the locking position, and 
           [0033]      FIG. 8   b  shows the partially cutaway connector from  FIG. 8   a  in the unlocking position. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0034]    An electrical connector  100  according to the invention and a mating connector  10  provided for it are shown in  FIG. 1 . The connector  100  is formed from two shell halves—a top shell  200  and a bottom shell  300 —and has a connecting side  120  and a cable side  110 . 
         [0035]    An unlocking mechanism which can be actuated by means of a pull tab  500  which can be displaced by a certain axial range is arranged inside the two shells. The pull tab is expediently fastened to a sliding element  400  which is a component of the unlocking mechanism. 
         [0036]      FIG. 2  shows in an exploded representation an overall view of the individual parts belonging to the connector. 
         [0037]    The bottom shell  300  is first shown here with the top shell  200  arranged above it. A printed circuit board  820  with an electrical cable  810  attached to it and a strain relief  860  surrounding the cable  810  is inserted in the bottom shell  300 . The sliding element  400  and a tiltable locking latch  600  which belongs to the unlocking mechanism are shown below the bottom shell  300 . A separate axle  650  is provided on the locking latch  600 , can be pushed into an axle mount  640  on the locking latch  600  (see  FIG. 6 ) and into an axle bore  350 ,  350 ′ on the bottom shell  300  (see  FIG. 4   b ) and thus permits a rotational movement of the locking latch  600  about the axle  650 . The unlocking mechanism is completed by the pull tab  500  and two coil springs  140 ,  140 ′ acting on the sliding element  400 . 
         [0038]    A shielding element  700  is provided to transfer the shielding effect from the electrical connector  100  to the mating connector  10 . 
         [0039]    The bottom shell  300  is shown in greater detail in  FIG. 3   a  and  FIG. 3   b . It has a half-open shell with two side walls  310 ,  310 ′, a cable fixing  370  formed on the cable side, and an open connecting side  120 . 
         [0040]    On the inner sides of the side walls  310 ,  310 ′, in the front region of the bottom shell  300  facing the connecting side  120 , a staircase-shaped formation  315 ,  315 ′ is provided in each case, on which the printed circuit board  820  rests when the latter is inserted into the electrical connector  100 , while two mouldings  215 ,  215 ′ which fix the printed circuit board  820  from the other side are provided in the top shell  200 . The fixing of the printed circuit board  820  on the connecting side  120  is important because the contacting with the mating connector  10  is effected via the electrical contacts  830  located on the said printed circuit board  820 . 
         [0041]    To achieve an EMC-sealed shell, stepped projections are provided on the edges of the side walls  310 ,  310 ′ and on the edges of the side walls  210 ,  210 ′ of the top shell  200  and engage inside each other when the two shells  200 ,  300  are assembled so that a type of labyrinth seal results. 
         [0042]    On the cable side  110 , a mount  360  for the strain relief  860  of the electrical cable  810  is additionally provided in the bottom shell  300  next to the cable fixing  370 . Two recesses which serve as a spring mount  340 ,  340 ′ for the coil springs  140 ,  140 ′ are provided on the inside of the lateral ends of the bottom shell  300 . 
         [0043]      FIG. 4   a  and  FIG. 4   b  show the bottom shell  300 , also in a detailed view but from the outside. A mount  380  in which the locking latch  600  can be placed is formed on the cable side  110  in the bottom shell  300 . The axle  650  is pushed through the axle bore  350 ,  350 ′ and the axle mount  640  of the locking latch  600 , as a result of which the locking latch  600  is housed rotatably on the bottom shell  300 . The axle bore  350 ,  350 ′ is provided in the bottom shell  300  to receive the axle  650 . Bores  390 ,  390 ′ situated on the outside of the bottom shell  300  serve to fix the shielding element  700 . 
         [0044]    The outer cable connection end  320  of the bottom shell  300  is provided so that it is enclosed by the sliding element  400 , as a result of which the unlocking mechanism situated inside is protected. 
         [0045]    The top shell  200  is shown in detail in  FIG. 5   a  and  FIG. 5   b . The already mentioned side walls  210 ,  210 ′ with the stepped projections can be seen in  FIG. 5   a , which form an EMC-sealed shell in conjunction with the side walls  310 ,  310 ′ of the bottom shell  300 . As illustrated in  FIG. 3   a  and  FIG. 3   b , the mouldings  215 ,  215 ′ serve to fix the printed circuit board  820  in the assembled shell  200 ,  300 . 
         [0046]    The detailed view in  FIG. 5   b  shows a cable fixing  270  and a strain relief mount  260  which each interact with the elements  370  and  360  on the bottom shell  300 . Recesses which serve as spring mounts  240 ,  240 ′ for the coil springs  140 ,  140 ′ are provided on the inside of both elongated sides of the cable connection end. 
         [0047]    A notch which forms a sliding track range  250 ,  250 ′ is in each case provided in the spring mounts  240 ,  240 ′. The sliding element  400  engages in the sliding track range  250 ,  250 ′ on both sides with provided sliding stoppers  420 ,  420 ′ in such a way that it limits the maximum sliding travel (see  FIG. 8   a  and  FIG. 8   b ). 
         [0048]      FIG. 6  shows a single locking latch  600  which is provided for mounting in the bottom shell  300 . The locking latch  600  is a T-shaped element, the transverse region of the “T” forming a first lever part  601  and the elongated region of the “T” forming a second lever part  602 . 
         [0049]    A sleeve-like axle mount  640  directed parallel to the transverse region of the “T” joins the first lever part  601  to the second lever part  602 . The axle mount  640  serves as the pivot point for the locking latch  600 . The axle  650  shown in the foreground, by means of which the locking latch  600  is housed rotatably on the bottom shell  300 , is guided through the axle mount  640 . The axle  650  is a component which is here designed as a slotted spring pin which is inserted with spring tension into the bore  350 ,  350 ′ in the bottom shell  300  to prevent it from falling out. 
         [0050]    At the outer ends of the first lever part  601 , a forked guide  610 ,  610 ′ is in each case provided, the opening of which is oriented at an angle of, for example, here 45° with respect to the centre line  660  of the locking latch  300 . The two forked guides  610 ,  610 ′ are spaced apart from each other by such a distance that the cable connection end  320  can be accommodated between them and that the sliding element  400  can engage around the locking latch  600 . 
         [0051]    The second lever part  602  has at its end a hook  620  which is arranged in such a way that, with respect to the centre line  660  of the locking latch  600 , it lies on the opposite side to the forked guides  610 ,  610 ′ on the first lever part  601 . The hook  620  has a triangular design corresponding to a recess  11  on the mating connector  10  into which the hook  620  latches in the locked situation. The hook  620  is flattened at the end facing the second lever part  602  in order to enable the mating connector to be locked. When locking the electrical connector  100  to the mating connector  10 , it is not necessary to release the unlocking mechanism as the mating connector  10  is latched on the hook  620  by elastic deformation. 
         [0052]      FIG. 7   a  and  FIG. 7   b  show a sliding element  400  from the cable connection direction and plug-in direction, respectively. The sliding element  400  is a thin-walled U-shaped component. It is mounted on the cable connection end  320  of the bottom shell  300 , the locking latch  600  being arranged between the cable side  320  and the sliding element  400 . 
         [0053]    A moulding  430 , which serves to receive and fasten the pull tab  500 , is provided in the centre of the lower part of the sliding element  400  on the inside. Sliding stoppers  420 ,  420 ′ are integrally formed on the lateral arms of the sliding element  400 . These sliding stoppers  420 ,  420 ′ engage in the sliding track ranges  250 ,  250 ′ on the upper shell  200  and limit the maximum axial sliding travel of the sliding element  400 . 
         [0054]    A mounting pin  440 ,  440 ′ for the coil springs  140 ,  140 ′, and guiding pins  410 ,  410 ′ around which engage the forked guides  610 ,  610 ′ of the locking latch  600 , are in each case situated on the insides of the lateral arms of the sliding element  400 . 
         [0055]    The mounting pins  440 ,  440 ′ move with the sliding element  400  inside the spring mounts  240 ,  240 ′,  340 ,  340 ′ of the shell  200 ,  300 . When the pull tab  500  is pulled, the sliding element  400  is thus moved counter to the plug-in direction by an axial sliding distance, as a result of which the coil springs  140 ,  140 ′ are compressed by means of the mounting pins  440 ,  440 ′ on the sliding element  400 . When the pull tab  500  is released, the sliding element  400  is displaced back into the starting position by the energy of the coil springs  140 ,  140 ′. 
         [0056]    During the movement of the sliding element  400 , the guiding pins  410 ,  410 ′ act on the forked guides  610 ,  610 ′ of the locking latch  600  which are guided about the pins. When the unlocking mechanism is actuated, the guiding pins  410 ,  410 ′ cause the locking latch  600  to tilt relative to the fixed but rotatable axle mount  640 , as a result of which the second lever part  602  is pulled into the bottom shell  300  with the hook  620  and the locking connection to the mating connector  10  is disengaged. 
         [0057]    When the pull tab  500  is released, the guiding pins  410 ,  410 ′, in conjunction with the forked guides  610 ,  610 ′, cause the locking latch  600  to be returned. This spring-loaded returning of the sliding element  400  ensures a secure locking connection between the electrical connector  100  and the mating connector  10 . 
         [0058]    The cable connection end of a electrical connector is shown in  FIG. 8   a  in a portion of the electrical connector  100  in the locking position, the unlocking mechanism being shown in partial section. 
         [0059]    The locking latch  600  is situated in a horizontal locking position parallel to the electrical connector  100 . The hook  620  projects out of the electrical connector  100  in order to permit locking to the mating connector  10 . The sliding element  400  is pressed by the coil springs  140 ,  140 ′ acting inside into a front end position which is defined by the sliding stopper  420  in the sliding track range  250 . The guiding pin  410  of the sliding element  400  is situated on the innermost point of the forked guide  610  of the locking latch  600 , as a result of which the locking latch  600  is prevented from rotating. 
         [0060]    Lastly,  FIG. 8   b  shows the cable connection end of the electrical connector from  FIG. 8   a  in the unlocking position, the unlocking mechanism also being shown here in partial section. 
         [0061]    The sliding element  400  is pulled into a rear end position by the actuation of the pull tab  500  counter to the spring action. The rear end position shown is, like the front end position from  FIG. 8   a , also defined by the sliding stopper  420  in the sliding track range  250 . The sliding travel of the sliding element  400  which releases the unlocking mechanism counter to the spring action is shown by the arrow  450 . 
         [0062]    The guiding pin  410  shifted counter to the plug-in direction with the sliding element  400  acts on the forked guide  610  and causes the locking latch  600  to rotate clockwise about the axle  650 . The rotation of the locking latch  600  causes a short lifting movement of the hook  620 , which thereby retracts into the shell  200 ,  300  and releases a locking connection to a mating connector  10 . 
       LIST OF REFERENCE NUMERALS 
       [0000]    
       
           10  mating connector 
           11  recess 
           100  electrical connector 
           110  cable side 
           120  connecting side 
           140 ,  140 ′ coil spring 
           150 ,  150 ′ screw 
           200  top shell 
           210 ,  210 ′ side wall 
           215 ,  215 ′ moulding 
           240 ,  240 ′ spring mount 
           250 ,  250 ′ sliding track range 
           260  strain relief mount 
           270  cable fixing 
           300  bottom shell 
           310 ,  310 ′ side wall 
           315 ,  315 ′ staircase-shaped formation 
           320  cable connection end 
           340 ,  340 ′ spring mount 
           350 ,  350 ′ axle bore 
           360  strain relief mount 
           370  cable fixing 
           380  mount 
           390 ,  390 ′ bore 
           400  sliding element 
           410 ,  410 ′ guiding pin 
           420 ,  420 ′ sliding stopper 
           430  moulding 
           440 ,  440 ′ mounting pin for coil spring 
           450  sliding travel 
           500  pull tab 
           600  locking latch 
           601  first lever part 
           602  second lever part 
           610 ,  610 ′ forked guide 
           620  hook 
           640  axle mount 
           650  axle 
           660  centre line 
           670  axis of rotation 
           700  shielding element 
           810  electrical cable 
           820  printed circuit board 
           830  electrical contacts 
           860  strain relief