Patent Publication Number: US-2022224033-A1

Title: Ribbon Cable Connector with a Clamping Device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of the filing date under 35 U.S.C. § 119(a)-(d) of German Patent Application No. 102021100679.1, filed on Jan. 14, 2021. 
     FIELD OF THE INVENTION 
     The invention relates to a ribbon cable connector which is configured to be fixed at one end of a ribbon cable that comprises multiple electrical conductors extending parallel and distanced to one another. 
     BACKGROUND 
     In a ribbon cable, several electrical conductors extend parallel to each other, wherein they are applied to a common insulation. Ribbon cables are often used for transmitting signals, for which they are also attached to ribbon cable connectors. In this context, the ribbon cables should occupy as little space as possible. However, miniaturization of the ribbon cable is accompanied by a risk of unwanted transmission of signals due to current flow between the parallel conductors, since the leakage path between directly adjacent conductors also decreases. 
     SUMMARY 
     A ribbon cable connector is fixed at an end of a ribbon cable. The ribbon cable has a plurality of electrical conductors extending parallel and distanced to one another. The ribbon cable connector includes an insertion slot extending in a plugging direction and receiving the ribbon cable, a plurality of contact element receptacles extending parallel and distanced to one another, a plurality of bulges in the insertion slot extending parallel to one another and aligned with the contact element receptacles, and a clamping device configured to clamp the ribbon cable in the insertion slot. An end of the insertion slot inside of the ribbon cable connector adjoins the contact element receptacles in the plugging direction. The bulges are each separated from one another by a partition wall. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will now be described by way of example with reference to the accompanying Figures, of which: 
         FIG. 1  is a sectional perspective view of a connector assembly according to an embodiment in a release position; 
         FIG. 2  is a top view of the connector assembly of  FIG. 1 ; 
         FIG. 3  is a sectional perspective view of the connector assembly of  FIG. 1 ; 
         FIG. 4  is a sectional side view of the connector assembly of  FIG. 1  in a clamping position; 
         FIG. 5  is a perspective view of a connector assembly according to another embodiment in a release position; 
         FIG. 6  is a sectional side view of the connector assembly of  FIG. 5  in a clamping position; 
         FIG. 7  is a perspective view of a connector assembly according to another embodiment in a release position; 
         FIG. 8  is a sectional side view of the connector assembly of  FIG. 7  in a clamping state; 
         FIG. 9  is a perspective view of a connector assembly according to another embodiment in a release position; and 
         FIG. 10  is a sectional side view of the connector assembly of  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENT(S) 
     In the following, the invention is exemplarily described in more detail by way of embodiments. Features of the embodiments can be omitted if the technical effect associated with these features is not important for a particular application. Conversely, further features can also be added to the embodiments if their technical effect should be important for a particular application. In the following, the same reference signs are used for features that correspond to each other in terms of function and/or spatial-physical configuration. 
     Initially, a first exemplary configuration of a ribbon cable connector  1  according to the invention is explained in more detail with reference to  FIGS. 1 to 4 . The ribbon cable connector  1  is configured to be attached to one end  2  of a ribbon cable  4  in a connector assembly  100 . 
     As shown in  FIG. 1 , the ribbon cable  4  has several electrical conductors  6  extending parallel and distanced to one another, which may be applied to a common insulation  8 , for example an insulating carrier film  10 . The insulation  8  is exposed between the adjacent conductors  6 . Alternatively, the conductors  6  may be surrounded by an insulating sheath, being at least partially exposed from the insulating sheath at the end  2 . In particular, the conductors  6  may extend parallel to a cable longitudinal axis L of the ribbon cable  4  and may be spaced apart from each other in a transverse direction T extending substantially perpendicular to the cable longitudinal axis L. 
     As shown in  FIG. 1 , the conductors  6  can each be connected to a contact element  11  at the end  2 , for example by crimping. Particularly in the case of miniaturized ribbon cables  4 , the distances between the conductors  6  can be small. For example, they may be smaller than 1 mm, smaller than 0.5 mm or even smaller than 0.4 mm. Consequently, a leakage path between the conductors  6  may be such that an unwanted signal transmission may occur due to current flow between the conductors  6 . Cuts or punch-outs in the insulation  8  between the conductors  6  are also undesirable, since this is associated with a higher production cost and this processing of the insulation  8  is not possible, especially for miniaturized ribbon cables  4 . 
     With a ribbon cable connector  1  according to the invention, it is now possible to fix one end  2  of the ribbon cable  4  between the conductors  6  without any cuts or punch-outs in the insulation  8 . For this purpose, the ribbon cable connector  1  has an insertion slot  12  shown in  FIG. 1  extending into the ribbon cable connector  1  in a plugging direction S extending substantially parallel to the cable longitudinal axis L for receiving the end  2  of the ribbon cable  4 . In this context, the insertion slot  12  adjoins contact element receptacles  16 , which are spaced apart from one another and extend parallel to one another, with its end  14 , which is located in the ribbon cable connector  1 , in the plugging direction S. 
     As shown in  FIG. 1 , the insertion slot  12  has bulges  18  which are aligned with the contact element receptacles  16  in the plugging direction S, extend parallel to one another and in the direction transverse to the plugging direction S, in particular in the direction transverse to the plugging direction S and to the transverse direction T, and are each separated from one another in the transverse direction T by a partition wall  20 . The plugging direction S and transverse direction T span a frontal plane E which, for example in  FIG. 2 , extends substantially perpendicular to the drawing plane. The bulges  18  on the outside in the transverse direction T can each be closed in the transverse direction T by a side wall  22  extending parallel to the partition wall  20 . In an embodiment, the wall  20  can extend continuously in the transverse direction T so that the bulges  18  are bounded by a common wall. 
     The partition walls  20  effect a deflection of the leakage path  23  around the corresponding partition wall  20  between the adjacent conductors  6  and thus lengthen the leakage path  23  so that a safe application of the ribbon cable connector  1  can be ensured without an unwanted transmission of signals between the individual conductors  6 . In  FIG. 1 , the leakage path  23  is shown in simplified form by a dashed line. 
     To fasten the ribbon cable  2  in the ribbon cable connector  1 , a clamping device  24  is further provided, which is configured to clamp the ribbon cable  2  in the insertion slot  12 . Therefore, the ribbon cable  4  can be additionally secured against falling out in the connector assembly  100 . A tensile load of the ribbon cable  2  is damped by the clamping device  24 , whereby the contacting of the contact elements  11  and the corresponding conductors  6  remains unaffected by this tensile load. Consequently, the contact element  11  can be prevented from breaking off. 
     As shown in  FIG. 2 , the insertion slot  12  can extend over its entire width substantially parallel to the transverse direction T of the ribbon cable  4  intended for this ribbon cable connector  1 , whereby the ribbon cable  4  can be easily received along its longitudinal axis L in the insertion slot  12 . Consequently, no further processing steps are necessary to enable the end  2  of the ribbon cable  4  to be partially received. 
     The partition walls  20  or also the side walls  22  can close the insertion slot  12  in the plugging direction S at the end  14  so that the ribbon cable  4  can be prevented from being inserted too deeply into the ribbon cable connector  1 . In an embodiment, the partition walls  20  can extend in the plugging direction S up to the contact element receptacles  16 , whereby the partition walls  20  extend along the entire depth of the insertion slot  12  in the plugging direction S. In an embodiment, the partition walls  20  of the insertion slot  12  can seamlessly merge into partition walls  20  between the contact element receptacles  16 . Thus, the respective pairs of partition walls  20  can be molded integrally with each other, for example as an injection-molded part. 
     Bulges  18  and contact element receptacles  16  can each be assigned to a conductor  6  so that an individual conductor  6  can be arranged in each bulge  18 . In an embodiment, the bulge  18  can extend substantially transversely to the frontal plane E. This allows insertion of the conductors  6  after termination with the respective contact elements  11 . In an embodiment, a cross-section transverse to the frontal plane E of a bulge  18  can overlap or even coincide with a cross-section of the corresponding contact element receptacle  16 , as can be seen in  FIG. 2 . Consequently, the respective conductor  6  of the ribbon cable  4  can already be terminated at a contact element  11 , for example a contact socket, before being inserted into the insertion slot  12 . The contact element  11  can simply be inserted with the ribbon cable  4  through the respective bulge  18  into the corresponding contact element receptacle  16 . 
     A wall  26  may be provided to limit the protrusions  18  in the direction transverse to the frontal plane E. The wall  26  can extend in the transverse direction T over the entire width of the insertion slot  12 , as shown in  FIGS. 1 and 2 . 
     The partition walls  20  or also the side walls  22  can in this case project from the wall  26  substantially transversely to the frontal plane E. If the stability of the partition walls  20  and the side walls  22  is to be reinforced, for example against bending, the partition walls  20  and the side walls  22  can have an increasing material thickness in the transverse direction T in the direction transverse to the frontal plane E. The material thickness of the partition walls  20  and the side walls  22  can be increased in the transverse direction T. For this purpose, for example, reinforcing ribs  28 , shown in  FIG. 2 , can be provided which extend from the wall  26  to a flat side of the respective partition wall  20  or side wall  22  facing in the direction of the corresponding bulge  18 . 
     The end of the respective partition walls  20  facing away from the wall  26  may have a material thickness smaller than the distance between the conductors  6  of the ribbon cable so that it can be ensured that the partition walls  20  are opposite the section of insulation  8  exposed from the conductors  6  when the ribbon cable  4  is plugged into the ribbon cable connector  1 . 
     The bulges  18  and the contact element receptacles  16  may be spaced apart from one another in the plugging direction S, and the region  30  may be open substantially transversely to the frontal plane E. Thus, the region  30  can form a receiving pocket  32  shown in  FIGS. 1 and 3  in which, for example, a secondary latch  34  can be received. The secondary latch  34  may be held by a lever arm  36  formed on the ribbon cable connector  1  so as to be pivotable about a rotation axis aligned substantially parallel to the transverse direction T. 
     In  FIGS. 1 to 3 , the secondary latch  34  is shown in an open position  38  in which it is arranged outside the receiving pocket  32 . In this open position  38 , the contact element receptacles  16  are released and the corresponding contact elements  11  can be inserted into the contact element receptacles  16 . If the secondary latch  34  is now transferred to a locking position  40 , as shown in  FIG. 4 , the secondary latch  34  protrudes into the receiving pocket  32  and covers the contact element receptacles  16 . Consequently, the secondary latch  34  blocks the contact elements  11  from falling out or being pulled out of the contact element receptacles  16 . 
     In an embodiment, the secondary latch  34  can be locked in the locking position  40 , for example by latching with the wall  26 , as can be seen in  FIG. 4 . For this purpose, the secondary latch  34  can have a latching projection  42  which, in the locking position  40 , abuts the wall  26  and prevents the secondary latch  34  from pivoting out of the receiving pocket  32  in a form-fitting manner. 
     To deflect the leakage path between the adjacent conductors  6  in the region  30  as well, the partition walls  20  or also the side walls  22  project beyond the bulges  18  in the plugging direction S and extend as far as the contact element receptacles  16 . In particular, the partition walls  20  and the side walls  22  can merge into partition walls  44  between the contact element receptacles  16  or the side walls  46  bounding the outer contact element receptacles  16 . In this case, the partition walls  20  can be narrowed transversely to the plugging direction S, in particular transversely to the frontal plane E, in the region between bulges  18  and contact element receptacles  16 . 
     In an embodiment, the respective partition walls  20  can form part of the clamping device  24 , at least in sections. Consequently, it can be ensured that clamping of the ribbon cable  4  takes place in the region between the conductors  6 . This prevents the conductors  6  from being damaged by the clamping. In addition, clamping with the partition walls  20  extends an air gap between the adjacent conductors  6 . The air gap no longer merely leads in a transverse direction T from one conductor  6  to the adjacent conductor  6 , but extends around the respective partition wall  20  between the conductors  6 . In this exemplary configuration, the partition walls  20  serve both to clamp the ribbon cable  4  and to insulate the adjacent conductors  6  from one another. 
     If the secondary latch  34  is to be continuous along the transverse direction T, as is the case in the first exemplary configuration, the partition walls  20  may be narrowed in the region  30  substantially transversely to the frontal plane E, in particular in the direction toward the insertion slot  12 . 
     Now, with reference to  FIGS. 3 and 4 , the clamping device  24  of the first exemplary configuration is described in more detail. 
     The clamping device  24  may comprise a pressing element  54  movable from a release position  48  ( FIGS. 1 to 3 ) to a clamping position  50  ( FIG. 4 ) and lockable in the clamping position  50 . In this exemplary configuration, the pressing element  54  is formed on a free end  56  of a lever arm  58  which is held pivotably about a rotation axis aligned substantially parallel to the transverse direction T. 
     In an embodiment, the lever arm  58  with the pressing element  54  and the lever arm  36  with the secondary latch  34  may be arranged on opposite sides of the ribbon cable connector  1  substantially transversely with respect to the transverse direction T. In particular, the partition walls  20  and the pressing element  54  can be arranged on different sides with respect to the insertion slot  12 . The pressing element  54  may be configured to bound the insertion slot  12  substantially transversely to the frontal plane and to be opposite the partition walls  20  and the side walls  22 , at least in the clamping position  50 . 
     In the clamping position  50  shown in  FIG. 4 , a clear width of the insertion slot  12  in the direction transverse to the frontal plane E can be smaller than in the release position  48 . The clear width can, for example, be greater than the material thickness of the ribbon cable  4  or at least of the insulation  8 . Thus, the ribbon cable  4  can be inserted into the insertion slot  12  without great resistance in the release position  48 . In the clamping position  50 , the clear width of the insertion slot  12  may be smaller than the material thickness of the ribbon cable  4 , in particular the material thickness of the insulation  8 . Consequently, in the clamping position  4 , the ribbon cable  4  may be pressed with high force by the pressing element  54  against a counter-holder element  60 , which in this exemplary configuration is formed by the partition walls  20  and the side walls  22 . 
     The clamping device  24  can limit the insertion slot  12  essentially transversely to the frontal plane E, in particular on both sides, at least in sections. For this purpose, the pressing element  54  and the counter-holder element  60  can lie opposite each other with respect to the insertion slot  12 . 
     If the partition walls  20  form the pressing element  54  at least in sections, the corresponding sections of the partition walls  20  can be integrally connected to one another on a module that is movable in the plugging direction in order to implement a synchronous, in particular simultaneous, movement of the corresponding sections of the partition walls  20 . The movable portion can slide along a run-up slope in the plugging direction S, via which a translation of the movement in the plugging direction S to a movement transverse to the plugging direction S, in particular transverse to the frontal plane E, takes place. 
     Accordingly, the ribbon cable  4  is only clamped in the region of the insulation  8  between the conductors  6 . Instead of being clamped, the conductors  6  can move into the corresponding bulges  18  and are thus protected from any stress caused by the clamping. 
     A latching mechanism  62  can be provided for locking the pressing element  54  in the clamping position  50 . For this purpose, the pressing element  54  can have a latching lug  64  projecting essentially against the plugging direction S, which engages in a complementary latching lug  66  in the clamping position  50 , as shown in  FIG. 4 . 
     As shown in  FIG. 4 , the clamping device  24  may be level with the bulges  18 , at least in sections, in the plugging direction S. Consequently, the clamping of the ribbon cable  4  can be further stabilized by the wall  26 . 
     To achieve a gentle and stable clamping, the clamping device  24  may extend substantially parallel to the plugging direction S over at least half of a depth of the insertion slot  12 . In an embodiment, the clamping device  24  can extend over at least two thirds of the depth of the insertion slot  12  or even over the entire depth of the insertion slot  12 . The clamping device  24  can extend essentially perpendicular to the plugging direction S, in particular perpendicular to the transverse direction T over the entire width of the ribbon cable  4  or the insertion slot  12 . Thus, the clamping force can be distributed over a large area and there is no punctual loading of the ribbon cable  4 . 
     The solution according to the invention allows the ribbon cable  4  to be inserted into the insertion slot  12 , wherein the combination of the clamping device  24  and the bulges  18  separated from each other by the partition walls  20  ensure a secure fixation of the ribbon cable  4  in the insertion slot  12  with an increased leakage path  23  between adjacent conductors  6 . The leakage path  23 , i.e. the shortest distance along the surface of the insulation  8  between two conductive parts  6 , is no longer the perpendicular to the longitudinal axis L of the cable  4  between the adjacent, parallel conductors  6 , since this path is blocked by the partition wall  20 . Therefore, the leakage path  23  extends around the partition wall  20 , lengthening it compared to the leakage paths in conventional ribbon cable connectors. Furthermore, processing of the end  2  of the ribbon cable  4 , such as cutting slots in the insulation  8  between the conductors  6 , can be avoided to allow insertion of the ribbon cable  4  into the ribbon cable connector  1 . If the ribbon cable  4  had to be processed, a minimum width of the insulation  8  between the conductors  6  that allows processing would be mandatory. Consequently, miniaturization of the ribbon cable  4  would be limited by the minimum width. 
     With the clamping device  24 , not only is the correct positioning of the ribbon cable  4  in the insertion slot  12  protected against displacement due to a tensile load, but also the vibration resistance of the connector assembly  100 , comprising the ribbon cable connector  1  and the ribbon cable  4 , can be improved. 
       FIGS. 5 and 6  show a second exemplary configuration of a ribbon cable connector  1  according to the invention, which is of particularly compact structure compared to the first exemplary configuration. For the sake of brevity, only the differences of the second configuration compared to the first configuration are discussed below. 
     According to the second configuration, the pressing element  54  may be formed by the secondary latch  34 . Consequently, a second lever arm is no longer provided. By moving the secondary latch  34  from the open position  38  ( FIG. 5 ) to the locking position  40  ( FIG. 6 ), the pressing element  54  is simultaneously moved from the release position  48  to the clamping position  50 . Therefore, the assembly effort is reduced and the ribbon cable connector is more user-friendly. 
     For example, as shown in  FIG. 6 , the pressing element  54  may have teeth  70  projecting from the secondary latch  34 , in particular from an end face  68  of the secondary latch  34 , wherein the teeth  70  are spaced apart from each other substantially parallel to the transverse direction T and, at least in the clamping position  50 , are arranged in line in the plugging direction S with the respective partition walls  20 . Accordingly, the pressing element  54  may be adapted to be substantially comb-shaped, with the teeth  70  pressing the insulation  8  of the ribbon cable  4  against the counter-holder element  60  in the clamping position  50 . The counter-holder element  60  is formed here by an outer wall  72  of the ribbon cable connector  1 . 
     In this second exemplary configuration, the partition walls  20  do not extend across the region  30  to allow access by the teeth  70  to the insulation  8  of the ribbon cable  4  in the clamped condition. Each of the teeth  70  may be received between two partition walls  20  in the receiving pocket  32  when latched. 
     The first and second exemplary configurations show a ribbon cable connector  1  integrally formed as a monolithic component  73 . The production of the ribbon cable connector  1  as a monolithic component  74  allows a simple and cost-effective fabrication, especially in high volumes. For example, the ribbon cable connector  1  may be a  3 D printed or injection molded part. 
     However, the ribbon cable connector  1  can also be configured as a multi-part, in particular two-part component  74 , which permits simple and cost-effective replacement of individual components. Exemplary configurations of a ribbon cable connector  1  as a two-part component  74  are described in more detail below with reference to  FIGS. 7 and 8  (third exemplary configuration) and  FIGS. 9 and 10  (fourth exemplary configuration). 
     In particular, the pressing element  54  may be subjected to a high load to exert the necessary clamping force on the ribbon cable  4 . Therefore, the pressing element  54  is a separate component  76  which is configured to be attached to a housing  78  of the ribbon cable connector  1 . In particular, the pressing element  54  can be repeatedly attachable, which ensures that the pressing element  54  can be easily replaced. This allows rapid and cost-effective replacement of the individual components in the event of damage. 
     Another advantage resulting from the two-part structure of the cable connector  1  is the possibility of optimizing the individual components for their individual tasks. For example, the pressing element  54  can be formed from a material with a high rigidity, which makes it possible to avoid undesirable deformation of the pressing element  54 . 
     In the third exemplary configuration shown in  FIGS. 7 and 8 , the pressing element  54  is provided with portions  80  of the partition walls  20  which, at least in the clamping position  50 , are assembled with complementary portions  82  to the partition walls  20  formed in the housing  78 . 
     As can be seen in  FIG. 7 , the pressing element  54  may be configured to be substantially comb-shaped, with a base extending parallel to the transverse direction T and the portions  80  of the partition walls  20  projecting from the base transversely to the frontal plane E. 
     A receptacle  84  can be formed in the housing  78 , as shown in  FIGS. 7 and 8 , which is configured to receive the pressing element  54  at least in the clamping position  50  in the plugging direction S. Accordingly, the pressing element  54  can be movable relative to the housing  78  substantially parallel to the plugging direction S. A guiding of the relative movement between the pressing element  54  and the housing  78  can be implemented by a tongue-and-groove connection. For this purpose, tongues  86  can project in the transverse direction T on the respective outer surfaces of the pressing element  54 , which can be inserted in a corresponding groove  88  formed on a side wall of the receptacle  84 . The pressing element  54  and the housing  78  are connected to one another in a form-fitting and/or force-fitting manner at least in the clamping state  50 . Alternatively or additionally, the pressing element  54  can be locked in a force-fitting manner in the clamping state  50 . 
     In  FIG. 7 , the ribbon cable connector  1  is shown in the release position  48 , in which the pressing element  54  is arranged outside the receptacle  84 . Accordingly, the ribbon cable  4  can be inserted into the insertion slot  12  without great frictional resistance. If the pressing element  54  is now moved into the receptacle  84  substantially parallel to the plugging direction S, the portions  80  press the insulation  8  against the outer wall  72  and clamp the ribbon cable  4 . 
     The complementary sections  82  may include a guiding that presses at least a part of the portions  80  in a direction transverse to the frontal plane E toward the outer wall  72 , thereby reducing the clear width of the insertion slot  12  in the clamping position  50 . Consequently, the movable pressing element  54  can be moved from the release position  48  to the clamping position  50  without high frictional resistance. Furthermore, the guiding holds the pressing element  54  in the clamping position  50  between the ribbon cable  4  and the complementary portions  82  in a force-fit manner. 
     In another embodiment not shown, the pressing element  54  may be locked in the clamping position  50  and/or in the release position  48 , for example, by a latching mechanism. Thus, the pressing element  54  may be latched to the housing  78  in the release position  48 , which may prevent loss of the pressing element  54 . In this context, the pressing element  54  may protrude out of the receptacle  84  such that the portion  80  is not pushed toward the outer wall  72  by the complementary portion  82 . 
     In an embodiment, in the clamping position  50 , the pressing element  54  may be located entirely within the receptacle  84 , whereby the clamping position  50  may be uniquely characterized. In particular, a surface of the pressing element  54  extending substantially perpendicular to the plugging direction S can be aligned with a surface of the housing  78  in the clamping position  50 . 
     In the fourth exemplary configuration shown in  FIGS. 9 and 10 , the partition walls  20  form the counter-holder element  60  analogously to the first exemplary configuration and are part of the housing. The outer wall  72  is penetrated by a window  90  in a region opposite the partition walls  20  with respect to the insertion slot  12 , into which the pressing element  54 , configured as a separate component  76 , can be inserted. For this purpose, a frame of the window  90  can be provided with a latching receptacle  92 , for example in the form of a slot, in which a latching hook  94  of the pressing element  54  engages at least in the clamping position  50 . The latching receptacle  92  can be accessible from the outside, whereby it is possible, for example, to press the latching hook  94  out of the latching receptacle  92  using a tool. 
     As can be seen in  FIG. 10 , in the clamping position  50 , the pressing element  54  can completely fill the window so that a surface of the outer wall  72  facing away from the insertion slot  12  is flush with a surface of the pressing element  54  facing away from the insertion slot  12 . 
     In the fourth exemplary configuration, the pressing element  54  may also be substantially comb-shaped, and the teeth  70  may be arranged directly opposite the partition walls  20 , at least in the clamping position  50 .