Abstract:
An electrical connector including: a terminal body; an insulator accommodated within a receptacle of the terminal body, the insulator having at least one cavity adapted for holding a terminal connected to a wire of a cable; a metal ferrule accommodated within the receptacle of the terminal body; wherein the metal ferrule has a crimp portion adapted to be crimped onto the cable; wherein the metal ferrule is form-fittingly connected to the terminal body; and wherein the metal ferrule has a sleeve like holding portion centering the ferrule within the receptacle.

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
       [0001]    The present disclosure relates to an electrical connector comprising a terminal body, an insulator accommodated within a receptacle of the terminal body, said insulator having at least one cavity adapted for holding a terminal connected to a wire of a cable, and a metal ferrule accommodated within said receptacle of said terminal body. The metal ferrule has a crimp portion adapted to be crimped onto said cable. 
       Background 
       [0002]    An electrical connector of this kind is disclosed in U.S. Pat. No. 4,310,213 A. 
         [0003]    Another electrical connector is disclosed in EP 1 540 771 B1. The disclosed connector has a terminal body in the form of an outer shell accommodating an insulator made of a dielectric material. The connector further comprises a ferrule in the form of a sleeve. The ferrule is placed onto the outer insulation of a cable. An outer braid of the cable, which serves as a shielding of the cable, is folded back onto an outer circumferential face of the ferrule. The ferrule is then inserted into a receptacle of the terminal body. As the terminal body is made of an electro-conductive material the terminal body is electrically connected to the shielding of the cable. The ferrule is press-fit into the terminal body and also serves to hold the insulator in place within the terminal body. The insulator accommodates a plurality of terminals which are electrically connected to wires of the cable. 
         [0004]    A further connector of that kind is disclosed in EP 1 905 131 B1. 
         [0005]    Such connectors are typically used for high-speed data connection systems which require a high data speed transmission and which are reliability. At high signal speeds, the signal degrades due to cross-talk interference between parallel orientated conductors. Therefore, twisted pair cables are widely used and further improved by a shielding of the cable and the connector. However, there is also an increasing need for low cost high-speed data connections without shielding. 
       SUMMARY OF THE INVENTION 
       [0006]    In one form, the present disclosure provides an electrical connector comprising a terminal body, an insulator accommodated within a receptacle of the terminal body, said insulator having at least one cavity adapted for holding a terminal connected to a wire of a cable, and a metal ferrule accommodated within said receptacle of said terminal body. The metal ferrule has a crimp portion adapted to be crimped onto said cable. The metal ferrule is form-fittingly connected to said terminal body and has a sleeve like holding portion centering the ferrule within the receptacle. 
         [0007]    The ferrule is made of metal and has a crimp portion adapted to be crimped onto said cable. In addition, the metal ferrule is form-fittingly connected to the terminal body. 
         [0008]    The ferrule is made of metal in order to enable the ferrule to be crimped onto the outer insulation of the cable. Crimping the ferrule onto the cable makes sure that the ferrule is safely fixed to the cable and provides a high resistance against axial movement along the cable. Since the metal ferrule is further form-fittingly connected to the terminal body it provides a high pull-out force resistance. 
         [0009]    Another aspect of the disclosure is that the same ferrule having one standardized size can be used for different outer diameters since the crimp portion is crimped and pressed onto the outer diameter of the cable and is adapted to the dimension of the cable by the crimping process. Hence, the terminal body, the insulator and the metal ferrule do not have to be adapted to different cable diameters. The same terminal body, insulator and metal ferrule can be used for different cable diameters. 
         [0010]    The electrical connector can be used for shielded cables and for unshielded cables. If a shielded cable is used, the shielding of the cable has to be electrically connected to the metal ferrule which further is in electrical contact to the terminal body. In this embodiment the terminal body has to be made of a conductive material. Alternatively, the electrical connector can also be used for an unshielded cable. In this case the terminal body can be made of plastic material in order to reduce costs. 
         [0011]    Preferably, the terminal body has substantially the form of a tube forming the receptacle. The ferrule is inserted into the tube like terminal body wherein the ferrule has a sleeve like holding portions centering the ferrule within the receptacle. The holding portion has an outer diameter which is adapted to the inner diameter of the portion of the receptacle which accommodates the holding portion so that the ferrule is centered without or with a very small radial play. The crimping portion is independent from the holding portion so that the crimping of the crimping portion does not influence the outer diameter of the holding portion. Therefore, as described above, the crimping portion can be adapted to different cable diameters without influencing the fit of the holding portion within the receptacle of the terminal body. 
         [0012]    Preferably, the holding portion of the ferrule is formed by wall portions which are bent into the form of a sleeve. The ferrule is preferably made of sheet metal bent into a substantial sleeve like form forming the holding portion as described before and the crimp portion. 
         [0013]    The holding portion and the crimp portion can be arranged consecutively in axial direction. 
         [0014]    In order to make sure, that the ferrule is mounted into the terminal body in a specific angular orientation around the longitudinal axis of the terminal body, the holding portion can be provided with a polarization rib projecting in a radial direction outwardly. The terminal body is then provided with a slot extending parallel to the longitudinal axis and in which the polarization rib can be inserted, when inserting the ferrule into the terminal body. 
         [0015]    For a person skilled in the art it is understood that the polarization means can be arranged vice versa. This means that the ferrule can be provided with a slot extending parallel to the longitudinal axis and the terminal body can be provided with a polarization rib extending into the slot of the ferrule. 
         [0016]    The receptacle of the terminal body has two portions, i.e. a forward portion and a rearward portion. The insulator is accommodated in the forward portion and the ferrule is accommodated in a rearward portion. In a mating direction of the electrical connector with a counter-connector the forward portion is arranged in a forward part of the terminal body and the rearward portion in the rearward part of the terminal body. Therefore, when mating the electrical connector with a counter-connector the insulator, which is adapted to accommodate electrical terminals, can be mated with an insulator with terminals of the counter-connector. The ferrule is, viewed in mating direction, behind the insulator. 
         [0017]    The insulator and the ferrule are inserted into the receptacle in an insertion direction parallel to the longitudinal axis of the terminal body. Preferably, the insertion direction is identical to the mating direction of the electrical connector. 
         [0018]    In insertion direction, the ferrule is axially supported against a first stop face arranged in the rearward portion of the receptacle. The first stop face ensures that during the insertion of the ferrule into the receptacle the ferrule can only be pushed until it reaches the first stop face. 
         [0019]    In addition, in insertion direction, the insulator can be axially supported against a second stop face arranged in the forward portion of the receptacle. The second stop face ensures that the insulator is not pushed too far into the receptacle of the terminal body when mounting it and inserting it into the terminal body. 
         [0020]    Both stop faces, i.e. the first stop face and the second stop face, ensure that the ferrule and the insulator cannot be pushed too far into the terminal in insertion direction. 
         [0021]    In order to ensure that the ferrule cannot be pulled out of the receptacle after the insertion the ferrule is form-fittingly held also in a direction opposite to the insertion direction. The ferrule can be provided with a locking projection supporting the ferrule against the terminal body in a direction opposite to the insertion direction. The locking projection projects from an outer circumferential surface of the ferrule in a radial direction. The locking projection projects into a locking opening of the terminal body and is supported against a holding face formed by said opening. For a person skilled in the art it is understood that this can be provided vice versa. The terminal body can be provided with a locking projection projecting radially inwardly towards the longitudinal axis and which projects into a locking opening of the ferrule. 
         [0022]    By inserting the ferrule into the terminal body the locking projection is deflected radially inwardly until it reaches the opening and the locking projection can move back into an undeflected position latching behind the locking face of the opening. The locking projection is, preferably, cut-out of the sheet metal material. 
         [0023]    Comparable to the support of the ferrule in a direction opposite to the insertion direction the insulator can also be held in a direction opposite to the insertion direction. For this reason the terminal body may be provided with at least one locking arm supporting the insulator against pull-out forces in the direction opposite to the insertion direction. The locking arm projects radially inwardly from the terminal body and is axially supported against a locking face of the insulator. By inserting the insulator into the terminal body the locking arm is deflected radially outwardly until the locking arm latches behind the locking face of the insulator. 
         [0024]    For a person skilled in the art it is understood that alternatively the terminal body can be provided with a locking arm latching behind a locking face of the terminal body. 
         [0025]    The crimp portion is preferably provided with crimp wings which are wound around the cable and overlap each other. The crimp wings can overlap in a radial direction. Alternatively, the crimp wings can be offset viewed in an axial direction so that they overlap in an axial direction. Both solutions provide that the crimping wings can be crimped to a different extend so that the crimp connection can be adapted to different outer diameters of the cable. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    Other objections and advantages will become apparent from the following detailed description referring to the accompanying drawings, wherein: 
           [0027]      FIG. 1  is an exploded view of a first embodiment of an electrical connector; 
           [0028]      FIG. 2  is a first longitudinal sectional view of the electrical connector according to  FIG. 1 ; 
           [0029]      FIG. 3  is another longitudinal sectional view of the electrical connector according to  FIG. 1 ; 
           [0030]      FIG. 4  is a perspective view of the electrical connector according to  FIG. 1 ; 
           [0031]      FIG. 5  is a longitudinal sectional view of the terminal body of the electrical connector according to  FIG. 1 ; 
           [0032]      FIG. 6  is a perspective view of a ferrule of the electrical connector according to  FIG. 1 ; 
           [0033]      FIG. 7  is a perspective view of another embodiment of a ferrule; 
           [0034]      FIG. 8  is a front view of the ferrule according to  FIG. 5  crimped to a cable having a small diameter; 
           [0035]      FIG. 9  is a front view of the ferrule according to  FIG. 5  crimped on to a cable with a bigger diameter than in  FIG. 8 ; 
           [0036]      FIG. 10  is an exploded view of a second embodiment of an electrical connector; 
           [0037]      FIG. 11  is a first longitudinal sectional view of the electrical connector according to  FIG. 9  and 
           [0038]      FIG. 12  is a second longitudinal sectional view of the electrical connector according to  FIG. 9 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0039]      FIGS. 1 to 5  depict a first embodiment of an electrical connector in different views and are described together. 
         [0040]    The electrical connector comprises a terminal body  1  in the form of a tube, an insulator  2  and a metal ferrule  3 . The tube like terminal body  1  accommodates the insulator  2  which is inserted into the terminal body  1  in an insertion direction M which is identical to a mating direction of the electrical connector for mating same with a counter connector. The insertion direction M is orientated parallel to a longitudinal axis L defined by the terminal body  1 . 
         [0041]    The electrical connector is part of a connector assembly which further comprises a connector housing  4  having a TPA (Terminal Position Assurance) device  5  mounted onto the connector housing  4 . The terminal body  1  is inserted into the connector housing  4  which can be connected to a connector housing of a counter connector assembly. 
         [0042]    The insulator  2  has a plurality of cavities  7  which are in the form of through openings in the insulator  2  and each of which accommodates one male terminal  6 . In the present embodiment the electrical connector has four male terminals  6 , each of which is connected to a wire  8  of a cable  9 . For persons skilled in the art it is understood that also other cables having a different number of wires can be used wherein the number of male terminals  6  is adapted to the number of wires  8 . 
         [0043]    The cable  9  has an insulation  10  covering the wires  8 . The ferrule  3  is placed and mounted, as described herein after, onto the insulation  10  of the cable  9 . Each of the wires  8  is also provided with an insulation  12  covering a conductor, latter being connected to the respective male terminal  6 . 
         [0044]    The receptacle  11  has a rearward portion  13  and a forward portion  14  wherein viewed in insertion direction M the forward portion  14  is arranged in front of the rear-ward portion  13 . Both portions  13 ,  14  of the receptacle  11  are substantially circular wherein the rearward portion  13  has a greater diameter than the forward portion  14 . The insulator  2  is arranged within the forward portion  14  and the ferrule  3  is arranged in the rearward portion  13 . The sub-assembly of cable  9 , insulator  2  and ferrule  3  is inserted in insertion direction M into the receptacle  11 . The Insulator  2  is pushed into the receptacle  11  until the ferrule  3  abuts a first stop face  15  within the rearward portion  13  of a receptacle  11 . The ferrule  3  has a first front face  20  which is supported against said first stop face  15 . The first stop face  15  is formed by a step between the rearward portion  13  having a greater diameter and the forward portion  14  having a smaller diameter. 
         [0045]    The insulation  10  of the cable  9  reaches into the forward portion  14  of the receptacle  11 . The insulator  2  in front of the insulation  10  of the cable  9  is inserted into the forward portion  14  of the receptacle  11  until a second front face  21  of the insulator  2  abuts a second stop face  19  of the terminal body  1 . In order to ensure that the male terminals  6  are correctly orientated in regard to the angular position around the longitudinal axis L the insulator  2  and the terminal body  1  have a polarization feature. The insulator  2  has a guiding slot  24  orientated parallel to the longitudinal axis L which is formed into an outer circumferential face of the insulator  2  and has an enlarged portion  26 . The enlarged portion  26  has a greater extension in circumferential direction than the rest of the guiding slot  24 . Between the enlarged portion  26  and the rest of the guiding slot  24  the second front face  21  is formed, as can best be seen in  FIG. 4 . 
         [0046]    Within the receptacle  11  the terminal body  1  has a guiding rib  25  extending parallel to the longitudinal axis L and projecting from the inner face of the terminal body  1  in a radial direction, as can be seen in  FIG. 5 . The guiding rib  25  also has an enlarged portion  27  having a greater extension in the circumferential direction than the rest of the guiding rib  25  so that the guiding rib  25  is adapted to the guiding slot  24  and is arranged within the guiding slot  24  in the mounted condition of the insulator  2  within the terminal body  1 . The enlarged portion  27  of the guiding rib  25  forms said second stop face  19  so that in a fully inserted condition of the insulator  2  within the terminal body  1  the second front face  21  of the insulator  2  abuts the second stop face  19  of the guiding rib  25 . 
         [0047]    Hence, it is ensured that neither the insulator  2  nor the ferrule  3  can be inserted too deep into the terminal body  1  and have a definite position in the insertion direction M. 
         [0048]    In order to ensure that the cable  9  cannot be pulled out of the terminal body  1  the ferrule  3  is provided with a lug  16  which projects from an outer circumferential face of the ferrule  3  in a radial direction and which projects into a locking opening  17  of the terminal body  1 . In a direction opposite the insertion direction M the lug  16  is axially supported against a locking face  18  of the locking opening  17 . The lug  16  is angled in regard to the longitudinal axis L such that during inserting the ferrule  3  into the cavity lithe lug  16  is pushed radially inwardly until the lug  16  reaches the locking opening  17  and deflects back into a relaxed position in which the lug  16  projects into the locking opening  17 . 
         [0049]    Due to the fact that the insulator  2  is only connected to the single wires  8  of the cable  9  by way of the male terminals  6 , the insulator  2  would be pushed towards the insulation  10  of the cable  9  when the electrical connector is mated with a counter connector so that the wires  8  would be bent or buckled. In order to avoid this, the terminal body  1  is provided with locking arms  22  which project into the receptacle  11  in a relaxed position. The locking arms  22  can be radially pushed outwardly when the insulator  2  is inserted into the receptacle and flip back into the relaxed position when the insulator  2  is in a fully inserted condition. In this fully inserted condition of the insulator  2  the locking arms  22  project behind second locking faces  23  of the insulator  2  so that the insulator  2  is supported in a direction opposite to the insertion direction M against the locking arms  22 . 
         [0050]    When the terminal body  1  is inserted into the connector housing  4  a wall portion  30  of the connector housing  4  avoids that the locking arms  22  can be pushed radially outwardly so that the locking arms are secured. Further, if the insulator  2  is not fully inserted into the terminal body  1  the locking arms  22  are pushed radially outwardly by the insulator  2  so that the locking arms  22  project over an outer circumferential face of the terminals body  1  and would collide with the wall of the connector housing  4  when trying to insert the terminal body  1  into the housing  4 . This ensures that the terminal body  1  can only be inserted into the connector housing  4  then the insulator  2  is fully inserted into the receptacle  11 . 
         [0051]    The ferrule  3 , which is shown in more detail in  FIGS. 6 to 9 , has a sleeve-like holding portion  28  and a crimp portion  29  which are arranged consecutively in axial direction of the longitudinal axis L. Viewed in the insertion direction M the crimp portion  29  is arranged in front of the holding portion  28 . The outer diameter of the holding portion  28  is adapted to the inner diameter of the rearward portion  13  of the receptacle  12  so that the ferrule  3  is centered to the longitudinal axis L within the rearward portion  13  of the receptacle  11 . The ferrule  3  is made of a sheet metal material and bent into the form as shown in the drawings. The holding portion  28  comprises two wall portions  30 ,  31  which are bent into the sleeve-like holding portion  28 . 
         [0052]    The holding portion  28  can be provided with a polarization rib  32  ( FIG. 7 ) which projects from the holding portion  28  in a radial direction and is orientated in the longitudinal direction L so that the ferrule  3  can be inserted with its polarization rib  32  into a polarization slot of the terminal body  1 . In the drawings only an embodiment of the ferrule  3  having a polarization rib ( FIG. 7 ) is shown but not a terminal body having a polarization slot. 
         [0053]    The crimp portion  29  has two crimp wings  33 ,  34 . The crimp wings  33 ,  34  are bent such that the crimp portion  29  has a sleeve-like form. The crimp wings  33 ,  34  are wound around the insulation  10  of the cable  9  and overlap each other. This means, that the crimp wings  33 ,  34  are arranged one behind the other viewed in insertion direction M . 
         [0054]    The overlapping of the crimp wings  33 ,  34  is important in order to ensure that the crimp portion  29  can be adapted to different cable diameters as shown in  FIGS. 8 and 9 .  FIG. 8  shows the crimp portion  29  being crimped onto a cable having a smaller diameter than the cable as shown in  FIG. 9 . Therefore, the same ferrule  3  can be used for different cable diameters so that cables with different diameters can be connected to one and the same terminal body  1 . As the holding portion  28  of the ferrule  3  centers the ferrule  3  within the rearward portion  13  of the receptacle  11  cables of different diameters can be connected with the terminal body  1 . 
         [0055]    The ferrule  3  also can be used for electrical connectors having male terminals and having female terminals.  FIGS. 10 to 12  show a counter connector as second embodiment of an electric connector having female terminals wherein the same ferrule  3  is used as in connection with the embodiment as disclosed in the  FIGS. 1 to 9 . In the  FIGS. 10 to 12  all elements having the same function as in the first embodiment are provided with the same reference numerals increased by  100  and are described in connection with the first embodiment.