A connector element for connecting a flexfoil and a pin-like contact member and a related connecting tool and method

Abstract: A connector element (6) for connecting a flexfoil (1) and a pin-like contact member (17), the connector element being made of a conducting material and comprising a base part (13), at least one clamping means (10) extending from a first side of the connector element (6) for clamping said flexfoil (1) and at least one further clamping means (10) extending from a second opposing side of the connector element (6) for clamping said flexfoil (1), and wall means (11; 22,23) arranged relative to said base part (13) to form an opening for receiving said pin-like contact member (17).

Description: The present invention relates to a connector element as defined in the preamble of claim 1. Such a connector element is known from DE-A-39 37 089. The front side of the known connector element is provided with ear-like wall means arranged for receiving a pin-like contact member. The rear side of the connector element is provided with clamping means provided with several thorns for clamping a flexfoil. For connecting the known connector element to a flexfoil, the thorns of the connector element are pushed through the flexfoil and through openings in the base of the connector element. After being pushed through these openings in the base of the connector element they are bent sidewards. By means of curved punches the back side of the connector is pressed firmly against the conducting part of the flexfoil. By providing one of these punches with sharp-pointed extensions, the electrical contact between the flexfoil and the connector element is improved. A direct electrical contact between a mating, pin-like terminal and conductors of a cable by means of a connector element is disclosed in DE-A-14 65 138. No clamping means are provided for to clamp the conductors of the cable against the connector element itself. It is an object of the present invention to provide a connector element for connecting a flexfoil and a pin-like contact member able to provide as many interconnecting and disconnecting operations as possible. Therefore, the present invention provides a connector element as defined in the characterizing portion of claim 1. Such a connector element is, in use, connected to the flexfoil by the action of the at least one clamping means, whereas the pin-like contact member may be inserted in the opening defined by the base part and the wall means arranged relative to said base part to form that opening. When inserted the pin-like contact member electrically contacts an exposed conducting path of the flexfoil. Preferably the connector element comprises a back side provided with at least one clamping lip for clamping said flexfoil. This at least one clamping lip enhances the robustness of the clamping between the connector element and the flexfoil. The connector element preferably comprises at least one opening in the base part adjacent to the at least one clamping lip. In use the at least one clamping lip is bent inward in the direction of the opening and pushes the rear side of the flexfoil into the opening thereby preventing any relative movement between the flexfoil and the connector element when a pin-like contact member is inserted into the connector element. In order to further reduce any possibility of relative movement between the flexfoil and the connector element the latter may be provided with an eye in the base part at the front side of the connector element for receiving a lip-like extension of the flexfoil. At least one further opening may be provided in the base part below at least one of the clamping means for providing the same purpose as the at least one opening in the base part mentioned above. The wall means arranged relative to said base part to form an opening for receiving the pin-like contact member preferably comprise two opposing, inward bent ears extending from opposite sides from the connector element. Such a connector element, then, may be integrally made by stamping from a thin sheet of metal and by bending the ears and the clamping means, as well as the clamping lip)s) if provided, into the proper position. This kind of connector elements can be easily and inexpensively produced. The clamping means may be fingers cut out from the ears. Cutting out from the ears may be easily carried out after the stamping operation mentioned above. Preferably the ears are arranged at the extremity of the connector designed for receiving the pin-like contact member and are provided with a bevelled edge for supporting lead-in of the pin-like contact member. By providing these bevelled edges insertion of a pin-like member into the connector element is an easy operation. The present invention is, moreover, directed to a set of the flexfoil and the connector element being connected together, the clamping means being bent inward to clamp the flexfoil and to electrically contact an exposed conducting path of said flexfoil. The connector element in such a set preferably comprises a back side provided with at least one clamping lip for clamping the flexfoil, each of the lips being bent inward and clamping the flexfoil by a crimping operation. Such a crimping operation is, preferably, carried out in such a way that the lips will be provided with dimples above corresponding openings within the base part of the connector element in order to create a strain-relief. Then, it is impossible to establish a relative movement between the flexfoil and the connector element by inserting a mating pin-like contact member into the connector element. The present invention is also related to a connecting tool for guiding a flexfoil into a connector element defined above and for crimping said flexfoil to said connector, comprising a crimping part at least provided with extensions for crimping the clamping means, and a guiding part for guiding the flexfoil into connector, the crimping part and the guiding part being slidable relative to one another. In such a connecting tool for guiding a flexfoil into a connector element and for crimping said flexfoil to said connector, the guiding part of the connecting tool may be provided with a slanted wall extending somewhat from its bottom side and suitable to be inserted into the eye of the connector for guiding a lip-like extension of the flexfoil into said eye. The invention also relates to a method of producing a set of a flexfoil and a connector element as defined above by using a connector and a connecting tool defined above, including the following steps: a. locating said connecting tool and said connector in a predefined relation to one another in which the guiding part abuts the connector; b. inserting the flexfoil into the connector; c. pushing the connecting tool against the connector with a predefined force and crimping at least the clamping fingers by means of the extensions. In step a of such a method of producing a set of a flexfoil and a connector element the slanted wall may be partly inserted into the eye of the connector. The present invention will be explained by referring to the annexed drawings showing some preferred embodiments of the present invention. It is observed that the drawings only disclose preferred embodiments and are not meant in any way to limit the scope of the present invention as defined in the claims. In the drawings: figure 1a, 1b, and 1c show a connector element according to the invention and a flexfoil, in which figure 1a shows them in a disconnected state, whereas figures 1b and 1c show them in a connected state; figure 2 shows schematically a top view of a connector connected to a flexfoil and a pin-like contact member inserted into the connector element; figure 3 shows a cross section along line III-III of figure 2; figure 4 shows a cross section along line IV-IV of figure 2; figure 5 shows a cross section along line V-V of figure 2; figure 6 shows schematically an alternative connector element for connecting a flexfoil and a pin-like contact member; figure 7a schematically shows a bottom view of a connecting tool for interconnecting the flexfoil and the connector element according to figures 1a through 5 and carrying out a crimping operation on the connector element for rigidly clamping action between the connector element and the flexfoil; figures 7b through 7d show in side views subsequent steps of connecting the flexfoil and the connector element according to figures 1a through 5 using the connecting tool of figure 7a. Figure 1a shows a flexfoil 1 provided with a contact terminal 3. The contact terminal 3 comprises an exposed conducting path 4. Reference L denotes the length of the contact terminal 3, which preferably corresponds with the length of the connector element 6. Preferably, the flexfoil comprises a lip-like extension 5, the purpose of which will be explained below. Except the contact terminal 3 and the lip-like extension 5, usually, the conducting path 4 is covered with an insulating layer 2. The conducting path may be made of copper. The connector element 6 comprises at least one clamping means 10, for example a finger as shown in figure 1a, extending from one side of the connector element 6. At least one other clamping means 10 may extend from an opposing side of the connector element 6 for clamping the flexfoil 1. In the arrangement shown in figure 1a the connector element 6 comprises two ear-like wall means 11 extending from opposing sides of connector element 6. These ears 11 are bent inward to form an opening for receiving a mating pin-like contact member 17 (figure 1b). The ears 11 and the clamping fingers 10 are arranged at a front side 8 of the connector element 6, which front side 8 is designed to receive the contact pin 17. At the side designed to receive the contact pin 17 the contact element 6 may be provided with an eye 14 for receiving the lip-like extension 5 of the flexfoil 1. This eye 14 may be provided in a separate extension 16 extending from a base part 13 of the connector element 6. In order to further enhance the clamping action between the flexfoil 1 and the connector element 6 the latter is preferably provided with a back side 7 provided with at least one clamping lip 9 for clamping the flexfoil 1 to the base part 13. The base part 13 may be provided with openings 15 both in the front side 8 and the back side 7. Their purpose will be explained below. The openings 15 in the front side 8 are preferably adjacent to or below each of the clamping fingers 10. Each of the ears 11 may be provided with a bevelled edge 12 in order to support the insertion of the pin-like contact member 17 into the connector element 6. In the arrangement shown in figure 1a the clamping fingers 10 are cut out from the ears 11. However, the clamping fingers 10 may be provided separately adjacent to the ears 11. The ears 11 are shown adjacent to the extension 16. However, alternatively clamping fingers 10 may be provided adjacent to the extension 16. If no extension 16 is present clamping fingers 10 may be provided directly adjacent to the front edge of the connector element 6. Then, instead of, or additional to, the bevelled edges 12 of the ears 11, the clamping fingers 10 may be provided with bevelled edges (not shown) to support insertion of the pin-like contact member 17. Of course, also in the arrangement shown in figure 1a, the clamping fingers nearest to the front edge of the connector element 6 may be provided with such bevelled edges (not shown). Figure 1b shows the flexfoil 1 and the connector 6 according to figure 1a in the connected state. The lips 9 are bent inward, and crimped afterwards, in order to rigidly clamp the flexfoil 1 against the back side of the contact terminal 3. Reference sign 18 designates crimp dimples which are preferably located above corresponding openings 15, the purpose of which will be explained below. Figures 1b and 1c (the latter showing essentially the same as figure 1b except that one of the ears 11 is broken away in order to more clearly show the contact fingers 10) both show the lip-like extension 5 being inserted into the eye 14 (figure 1a). Moreover, they show that the contact fingers 10 clamp the flexfoil 1. Both the contact fingers 10 and the clamping lips 9 electrically contact the conducting path 4 of the flexfoil 1. Figure 2 shows a top view of the connector element 6 connected to the flexfoil 1 at the back side 7 and accommodating a mating pin-like contact member 17 inserted into the front side 8. The same parts as in figures 1a, 1b, and 1c are designated by the same reference signs. Figure 3 shows a cross section through the connector element according to figure 2 along line III-III. From figure 3 it can be deduced that the clamping fingers 10 are bent inward to the base part 13 of the connector element 6 in such a way that the flexfoil 1 is rigidly clamped between the base part 13 and the clamping fingers 10. Moreover, it can be seen that the ears 11 are bent inward in the direction of the base part 13 to an extent to define an opening between their extremities and the base part 13, suitable for receiving the mating pin-like contact member 17. Moreover, the distance between two opposite clamping fingers 10 is designed in such a way that it corresponds to the width of the pin-like contact member 17. When inserted, the pin-like contact member 17 electrically contacts the conducting path 4 of the flexfoil 1. The conducting path 4 is supported by a flexfoil base 19. Figure 4 shows a cross section through the connector element 6 according to figure 2 along line IV-IV. This line IV-IV intersects two opposing crimp dimples 18. These crimp dimples 18 are the result of the crimping operation referred to above. It can be clearly seen from figure 4 that the clamping lips 9 are bent in the direction of the base part 13 to rigidly clamp the flexfoil 1 and that each of the lips 9 electrically contacts the conducting path 4 of flexfoil 1. Figure 5 shows a cross section through the arrangement according to figure 2 in the lengthwise direction along line V-V. The same parts as in the preceding figures are designated by the same reference signs. They will not be repeated here. From figure 5 it can be deduced that the eye 14 receiving the lip-like extension 5 of the flexfoil 1 is, preferably, not perpendicular to the surface of base part 13, but has an angle of inclination relative to this surface substantially smaller than π/2. By the provision of this inclined eye 14 the inserted lip-like extension 5 abuts extension 16 of the connector element 6. Therefore, the lip-like extension 5 cannot easily leave the eye 14 in a direction perpendicular to the surface of base part 13. Still, the lip-like extension 5 does not substantially extend from the bottom side of the base part 13, thereby keeping the space needed for the arrangement shown in figures 2 to 5 as small as possible. It can be clearly seen from figure 5 that the clamping fingers 10 are bent to the base part 13 to an extent that the flexfoil 1 below these clamping fingers 10 is somewhat forced into the openings 15. Therefore, the possibility of sliding of the flexfoil in the longitudinal direction is reduced. Moreover, the lips 9 are crimped into the direction of the base part 13. Crimp dimples 18 result from this crimping operation preferably in such a way that they are located above corresponding openings 15 thereby creating the same effect as clamping fingers 10 above corresponding openings 15. Figure 6 shows an alternative embodiment of a connector element 6' according to the invention. The same parts are designated with the same reference signs as in the preceding figures. Instead of ears 11 the front side 8 of the connector element 6' is provided with a box-type casing comprising a cover part 22 opposite to base part 13 and side walls 23 interconnecting the cover part 22 and the base part 13. The cover part 22, the side walls 23 and the base part 13 are designed in such a way as to define an opening for receiving a pin-like contact member 17, as shown in figure 1b. The cover part 22 may be provided with one or more dimples 21 to provide a better clamping action between the mating pin-like contact member 17 and the connector element 6' when the contact member 17 is inserted in the connector element 6'. Like the connector element 6 ithe preceding figures, the clamping fingers 10 may be made by cutting out from the side walls 23. Except for the amendments to the front side 8, the connector element 6' corresponds to all embodiments of the connector element 6 shown in the preceding figures and/or described above. Figure 7a shows a bottom view of an example of a special connecting tool 24 for guiding the flexfoil into the connector element 6 and to crimp the clamping fingers 10 and the clamping lips 9 on the flexfoil 1 in order to create a strain/relief, as described above. The connecting tool 24 comprises two parts: a crimping part 25 and a guiding part 26 (see also figures 7b through 7d). The crimping part 25 is provided with a first extension 28 at the bottom for crimping the clamping lips 9 as will be explained below. Extension 28 may cover the entire width of the crimping part 25, as shown in figure 7a. Moreover, the crimping part 25 is provided with as many second extensions 29 as there are clamping fingers 10 for crimping these fingers 10 as will also be explained below. The crimping part 25 comprises an opening 33 for receiving an extension 34 of the guiding part 26. The extension 34 is slidable up and down within the opening 33 as will become more clear from the description of figures 7b through 7d below. From the side view of figure 7b it is evident that the bottom wall of the crimping part 25 is, preferably, subdivided into a first slanted wall 30, a guiding wall 31 and a second slanted wall 32. The second slanted wall 32 extends somewhat below the main bottom wall of guiding part 26 to cooperate with eye 14 of connector 6. Figure 7b shows the connecting tool 24 in its state before a guiding/crimping operation in which a spring 27 forces the guiding part 26 downward relative to the crimping part 25. Figure 7c shows the connecting tool 24 in a guiding position for a flexfoil 1 relative to the connector 6. In the situation of figure 7c, the ears 11, the lips 9 and the clamping fingers 10 are already pre-bent but the spaces left between the lips 9 and the base part 13, and between the fingers 10 and the base part 13 are large enough for the flexfoil 1 to be inserted and connected. The connector 6 and the connecting tool 24 are moved relative to one another to the situation shown in figure 7c, i.e. the situation in which the connector 6 only abuts guiding part 26. The extension 34 is thin enough to be received by the space available between the two opposing ears 11 of the connector 6. The second slanted wall 32 is guided into the eye 14 to produce a predefined relation between the connecting tool 24 and the connector 6 before inserting the flexfoil 1. Then, the flexfoil 1 is inserted into the connector in the direction of arrow P: the front edge of the flexfoil 1 is guided between the lips 9 and the base part 13. The flexfoil is guided by the first slanted wall 30 of the guiding part 26 and then further guided by the flat guiding wall 31 and the second slanted wall 32. The lip-like extension 5 of the flexfoil 1 (see figure 1a) is automatically guided into eye 14 by the second slanted wall 32. Then, the connector 6 and the connecting tool 24 are further pushed towards one another by exerting a predefined force. The guiding part 26 is able to slide within the opening 33 of the crimping part 25 against the action of spring 27 and retains the same relative position to the connector 6. The crimping part 25, however, is pushed against the connector: its first extension 28 pushes the lips 9 against the flexfoil 1 whereas the second extensions 29 push the fingers 10 against the flexfoil 1, as shown in figure 7d. By moving the connector 6 away from the connecting tool 24 the extension 34 of the guiding part 26 leaves the space between the ears 11 and the second slanted wall 32 leaves the eye 14. The connecting tool shown in figures 7a through 7d is designed to be used with the connector 6 of figures 1 through 5. However, a connecting tool suitable for use with a connector 6' of figure 6 may be designed in accordance with the same principles. For the connector 6' as shown in figure 6, of course, the extension 34 of the guiding part 26 must be omitted or, alternatively, the cover part 22 of connector 6' must be provided with a notch to receive the extension 34 of the guiding part 26.

Claims: A connector element (6, 6') having a front side (8) for receiving a pin-like contact member (17) and a back side (7) for receiving a flexfoil (1) for making an electrical connection between said flexfoil (1) and said pin-like contact member (17), the connector element being made of a conducting material and comprising a base part (13), at least one clamping means (10) extending from a first side of the connector element (6, 6') for clamping said flexfoil (1) and at least one further clamping means (10) extending from a second side of the connector element (6, 6') opposing said first side for clamping said flexfoil (1), and wall means (11; 22, 23) arranged relative to said base part (13) to form an opening for receiving said pin-like contact member (17) characterized in that seen from the front side (8), at least part of the wall means (11; 22, 23) is arranged behind said at least one clamping means (10) and said at least one further clamping means (10). A connector element (6, 6') according to claim 1 wherein the at least one clamping means (10) and the at least one further clamping means (10) are shaped such that, after being crimped in a position to clamp the flexfoil (1) they define side walls of said opening for receiving said pin-like contact member (17). A connector element (6, 6') according to claim 1 or 2 wherein the back side (7) is provided with at least one clamping lip (9) for clamping said flexfoil (1). A connector element (6, 6') according to claim 3 comprising at least one opening (15) in the base part (13) adjacent to the at least one clamping lip (9). A connector element (6, 6') according to any of the preceding claims comprising an eye (14) in the base part (13) at the front side of the connector element for receiving a lip-like extension (5) of said flexfoil (1). A connector element (6, 6') according to any of the preceding claims comprising at least one further opening (15) in the base part (13) below at least one of the clamping means (10). A connector element (6) according to any of the preceding claims wherein said wall means (11) arranged relative to said base part (13) to form an opening for receiving said pin-like contact member (17) comprise two opposing, inward bent ears (11) extending from opposite sides from the connector element. A connector element (6) according to claim 7 wherein the clamping means (10) are fingers cut out of said ears (11). A connector element (6) according to any of the claims 7 or 8 wherein said ears (11) are arranged at the extremity of the connector designed for receiving the pin-like contact member (17) and are provided with a bevelled edge (12) for supporting lead-in of said pin-like contact member (17). A set of a flexfoil (1) and a connector element (6, 6') according to any of the preceding claims, the flexfoil (I) and the connector element (6, 6') being connected together, the clamping means (10) being bent inward to clamp the flexfoil (1) and to electrically contact an exposed conducting path (4) of said flexfoil (1). A set of a flexfoil (1) and a connector element (6, 6') according to claim 10, said connector element (6, 6') comprising a back side (7) provided with at least one clamping lip (9) for clamping said flexfoil (1), each of said lips (9) being bent inward and clamping said flexfoil (1) by a crimping operation. A connecting tool (24) for guiding a flexfoil (1) into a connector clement (6; 6') according to any of the claims 1 through 9 and crimping said flexfoil (1) to said connector (6, 6'), comprising a crimping part (25) at least provided with extensions (29) for crimping the clamping means (10), and a guiding part (26) for guiding the flexfoil into connector (6, 6'), the crimping part (25) and the guiding part (26) being slidable relative to one another. A connecting tool according to claim 12 for guiding a flexfoil (1) into a connector element (6; 6') according to claim 5 and crimping said flexfoil (1) to said connector (6, 6'), the guiding part (26) of the connecting tool (24) being provided with a slanted wall (32) extending somewhat from its bottom side suitable to be inserted into the eye (14) of the connector (6, 6') for guiding a lip-like extension (5) of the flexfoil (1) into said eye (14). Method of producing a set of a flexfoil (1) and a connector element (6, 6') according to any of the claims 10 or 11 by using a connector according to claims 1-9 and a connecting tool (24) according to any of the claims 12 or 13, including the following steps: a. locating said connecting tool (24) and said connector (6, 6') in a predefined relation to one another in which the guiding part (26) abuts the connector (6, 6'); b. inserting the flexfoil (I) into the connector (6, 6'); c. pushing the connecting tool (24) against the connector (6, 6') with a predefined force and crimping at least the clamping fingers (10) by means of the extensions (29). Method of producing a set of a flexfoil (1) and a connector element (6, 6') according to claim 14 wherein in step a. the slanted wall (32) is partly inserted into the eye (14) of the connector (6, 6').

Inventors: LIBREGTS HUBERTUS BERNARDUS, LIBREGTS, HUBERTUS BERNARDUS
Applicants: BERG ELECTRONICS MFG, BERG ELECTRONICS MANUFACTURING B.V.
Application year: 1995
Main classification: H01R4
IPC codes: H01R43, H01R4, H01R13, H01R12