Connector

Abstract: A connector (2) comprises, a housing having (10) at least one open side surface (11), a plurality of contact end portions (60 and 80) alternately arranged at a first position which is spaced away from the opening by a pre­ determined distance along a first surface (13) perpen­ dicular to the open side surface (11) in the housing, and is close to a surface opposite (15) the first said surface, and at a second position closer to the opening than the first position by a predetermined distance and shifted to the first side surface (11), and a slider (12) having a structure which can be fitted in the housing to clamp a cable (14) inserted forwards the first side surface (11) in said housing for electrical connection with the contact end portion in the housing, the slider having an indentation (20) at a distal end portion.

Description: The present invention relates to a connector for electrically connecting a flexible cable, in which contact terminals are arranged with high density, to an electrical circuit such as a printed circuit board and, more particularly, to a small-sized connector which can achieve excellent contact with a flexible cable in which a large number of contact terminals are alternately arranged in a staggered form at very small pitches. Recently, the sizes of electrical circuits such as printed circuit boards have been extremely reduced. At the same time, a demand has arisen for increased integration densities of the circuits themselves. In order to meet these demands small-sized, high-density flexible cables and connectors have been produced to connect between these types of electrical circuits. For this reason, in e.g., a flexible cable, contact terminals are alternately arranged in staggered form, so that a large number of contact terminals can be arranged with high density in a very small area. Such a flexible cable is connected to a connector attached to a high-density connecting portion of a printed circuit board. A conventional connector of this type includes contactors arranged on one side surface of a connector housing and brought into electrical contact with contact terminals of a cable inserted in the housing. The connector also includes a slider for urging the contact terminals of the flat flexible cable, inserted in the connector housing, against the contactors in the connector housing and connecting the terminals to the contactors. After the cable is inserted in the housing, this slider is fitted into the housing to clamp the connecting portion of the cable with the one side of the housing. When the contact terminals of the cable are arranged in staggered form as described above, however, contact terminals are alternately arranged at front and rear positions with reference to the end portion of the cable, along their longitudinal direction. Therefore. a contactor train in the connector housing which is electrically connected to the contact portions of the cable is arranged to have an interval in a direction to insert the cable. Therefore, the size of the connector housing is increased. In addition, space for a cable inserted in and connected to the connector housing and space to allow for fitting the slider are required. Therefore, in the arrangement of a conventional connector the size of the entire connector is inevitably increased. Another problem is that when the cable is clamped with the connector housing for connection, or when the cable is disconnected from the connector, the distance of movement, i.e. removal and insertion of the slider with respect to the connector housing, is increased, thus increasing the size of the entire connector. It is, therefore, an object of the present invention to provide a connector which can minimize the pitches of contact terminals of a cable and connector serving as connecting means, since these pitches are required by the development of a high-density electrical circuit such as a printed circuit board, and which can decrease the size thereof while maintaining an excellent connection between the cable and connector. EP-A-0320250 describes an electrical connector for connecting a flat flexible cable to a printed circuit board. Terminal contacts are mounted in a space in a housing and these contacts have legs which are of two different lengths to correspond to contact areas of the cable. The cable is inserted into the space in the housing with the aid of a plug or slider which urges the contact areas of the cable into contact with the legs of the contacts. According to the preamble of claim 1, and as is known from EP-A-0320250, an electrical connector for use with a flat flexible cable with a plurality of conductors comprises a housing having a space therein accessible through an opening in one side, the space serving for receiving said flexible cable; a plurality of first and second electrical contactors arranged alternately side by side within said space, each of said electrical contactors having a contact end portion for electrically contacting one of said conductors of said flexible cable, all of said contact end portions extending along said space toward said opening in the housing, in a direction opposite to that in which the cable is received with the distance over which the contact end portions of all the first contactors extend being greater than the distance over which the contact end portions of all the second contactors extend and a slider for inserting said flat flexible cable through said opening and into the space of the housing to contact said first and second electrical contactors. In contrast to EP-A-0320250, and in accordance with the invention, each of said contact portions also extends across said space perpendicularly to the direction in which the cable is received to a predetermined depth, with each of the contact end portions of said first contactors extending across said space to a depth which is less than the depth to which each of the contact end portions of the second contactors extend and said slider includes a forward end portion having a thickness which substantially corresponds to the transverse depth of the gap left in the space by all of the contact end portions of said second contactors and a rearward portion having a thickness which substantially corresponds to the transverse depth of the gap left in the space by all of the contact end portions of said first contactors, thereby providing for electrical contact between each of said contact end portions and a predetermined conductor of said flat flexible cable. Thus, the contact end portions of the contactors in the housing are staggered in two directions, i.e., in a back-and-forth direction and a height direction. Even if the pitch between the adjacent contact terminals of the cable conductors is very small, sufficient pitches can be obtained with a connector according to the invention to achieve excellent electrical connection with the contact terminals of the cable, with high reliability. The slider can be provided with an indentation which defines substantially said forward end portion, the depth of said indentation being greater than the thickness of said flat flexible cable. Therefore, a gap required to insert the cable is formed between the slider and an inner wall of the housing, so that the flat cable can be inserted into the connector housing without completely removing the slider from the housing. It is desirable that the indentation provides a smoothly inclined surface facing the contact end portions and merging the forward end rearward portions of the slider. Utilizing this arrangement of the contactors and the slider, a relatively thin portion is formed at the distal end region of the slider to compensate for the difference in the heights of the contact end portions. This portion of the slider is utilized as a gap formation means to assist the insertion of the flexible cable, and as an urging member for the contact end portions at the innermost region of the housing. Therefore, the space required to insert the cable, and the size of the slider are minimized, thus achieving a small-sized connector. This is one of the advantages of the present invention. The contactors may also have U-shaped portions disposed in the housing space. The first and second contact end portions can then alternately form one arm of each of said U-shaped portions of adjacent electrical contactors with the forward end portion of said slider being adapted to slide within said U-shaped portions when inserted into said space of the housing. The invention can be more fully understood from the following detailed description when taken in conjunction with the accompanying drawings, in which: Figure 1 is a perspective view of a connector according to an embodiment of the present invention; Figure 2 is a view showing a flexible cable connected to a connector of the present invention and, in particular, the arrangement of contact terminals; Figs. 3 and 4 are sectional views respectively taken along the lines 1 - 1 and 3 - 3 of Fig. 1, each showing the shape of a side surface of a contactor which constitutes the connector of the present invention, and showing the positional relationship between the connector housing and the slider; and Figs. 5 and 6 are sectional views respectively taken in the same manner as in Figs. 3 and 4, for explaining the relationship between the connector and the cable achieved when the cable is attached to the connector according to the present invention. Fig. 1 shows an embodiment of the present invention. A connector 2 shown in Fig. 1 includes a housing 10, in which a large number of first and second contactors 6 and 8 are alternately and linearly arranged, and a slider 12, fitted into the housing. A side of the housing 10 with a first side surface 11 has an opening through which an internal space 4 of the housing communicates with the outside. Fig. 2 is a plan view of a flexible cable 14 used for the connector of the present invention. The flexible cable 14 includes a large number of conductors (lead wires) arranged parallel to each other on a base consisting of an insulating material. In an end portion of the cable, each lead wire has a contact terminal 16a or 18a. The terminals 16a and 18a are alternately arranged in a staggered form on the base. Each of portions 16b and 18b in the lead wires which are not in contact with the connector are covered with an insulating protective film 201. Fig. 3 is a cross-sectional view of the connector 2 taken along the line 1 - 1 of Fig. 1, and Fig. 4 is a cross-sectional view of the connector 2 taken along the line 3 - 3 of Fig. 1. A large number of first and second contactors 6 and 8 alternately and linearly arranged in the housing 10 have arm portions 61 and 81, respectively. The cross section of each of the arm portions 61 and 81 is substantially U shaped, as shown in Figs. 3 and 4. The first and second contactors 6 and 8 have contact end portions 60 and 80, at the end portions of the arm potions 61 and 81, respectively. A surface 62 opposite the contact end portion 60 of the arm portion 61 and a surface 82 opposite the contact end portion 80 of the arm portion 81 are located on the same plane. A difference between the contactors 6 and 8 is that the positions of the contact end portions 60 and 80 are differ relatively in two directions, i.e. in directions orthogonal to the surface 11 and the surfaces 62,82 forth and heightwise. First, the contact end portion 60 of the contactor 6 is located at a first position which is spaced away from the opening portion by a predetermined distance in a direction parallel to a first internal surface 13, perpendicular to the first side surface 11 of the housing 10, i.e. the direction A of insertion of the slider 12 to the connector housing 10, and is close to the surface 15 opposite the first side 11. In contrast to this, the contact end portion 80 of the contactor 8 is located at a second position which is closer to the opening portion than the first position by a predetermined distance, and is positioned toward the first side surface 11. Second, the heights of the contact end portions 60 and 80 are different from each other, i.e., the contact end portion 60 of the first contactor 6, far from the opening portion of the housing, extends farther than the contact end portion 80 of the second contactor 8 with respect to the opposite surfaces 62 and 82. As shown in Fig. 1, therefore, the contact end portions 60 of the plurality of contactors 6 are linearly arranged to form a single train, while the contact end portions 80 of the other contactors 8 are linearly arranged to form another single train. The contactors 6 located deep in the housing are brought into electrical contact with the contact terminals 16a, linearly arranged near the end portion 14a of the flexible cable 14 as shown in Fig. 2, at the contact end portions 60, and the contactors 8 located near a cable insertion port in the housing are brought into electrical contact with the contact terminals 18a linearly arranged at the contact end portions 80, at positions farther from the end portion 14a of the flexible cable 14 than the other contact terminals 16a. Gaps 63 and 83, respectively formed by the arm portions 61 and 81 of the contactors 6 and 8, receive the flexible cable 4 and the slider 12. The thickness of the slider 12 is changed substantially in correspondence with the heights of the gaps 63 and 83 respectively formed by the arm portions 61 and 81 of the contactors 6 and 8. More specifically, in the slider 12, an indentation 20 is formed in a part extending from the distal end by a predetermined distance, as shown in the cross-sectional views in Figs. 3 and 4. The thickness of the portion in which the indentation 20 is formed is less than that of the other portion. The indentation 20 of the slider 12 extends in the direction of insertion into the housing to a point substantially intermediate between the first and second contact end portions with respect to the side surface 15, opposite the side surface 11 defining the opening. The indentation 20 is preferably formed such that when the slider 12 is inserted into the space 4 in the housing 10, i.e. into a gap formed by the contactors 6 and 8 arranged in the housing 10, and abuts against the end of the gap, i.e. the deepest portions of the arms 61 and 81 of the contactors 6 and 8, the boundary between a thin portion 21 and the other portion 22 in the slider 12 is located between the contact end portions 60 and 80 of the above-mentioned two types of contactors 6 and 8, which are staggered. In addition, the depth of the indentation 20 of the slider 12, that is the difference in thickness between the thick 22 and the thin 21 portions, is preferably greater than the thickness of the flexible cable to be connected. Moreover, as shown in Figs. 3 and 4, in the cross-sectional shape of the indentation 20 formed in the slider 12, a smoothly inclined surface is preferably formed without a sharp step at the boundary between the thick and thin portions 21 and 22 of the slider 12. Use of the connector according to the present invention with the above arrangement will be described below with reference to Figs. 5 and 6. As shown in Fig. 5, the slider 12 is removed from the connector housing 10 by a distance corresponding to the length of a substantially horizontal flat portion of the indentation 20. While the thin portion 21 is entirely or partially left in the housing, the cable 14 is inserted into the gaps 63 and 83 of the contactors 6 and 8 in the housing 10 through the gap between the contactor 8 near the cable insertion port in the connector housing 10 and the slider 12. At this time, the cable 14 is inserted into the gaps 63 and 83 of the contactors 6 and 8 while being smoothly curved along the inclined boundary of the indentation 20 of the slider 12. As shown in Fig. 5, when the distal end of the cable 14 abuts against the end of the gap of the contactors 6 and 8, and before the slider 12 is completely inserted into the housing 10, a group of the contact ends 60, linearly arranged at a lower position far from the cable insertion port in the housing 10, abuts or substantially abuts against a group of the contact terminals 16a near the end portion of the cable 14. At the same time, a group of the contact end portions 80, which is linearly arranged at a higher position near the cable insertion port in the housing 10 abuts or substantially abuts against a group of the contact terminals 18a far from the end portion of the cable 14. When the slider 12 is pushed into the deep portions of the gaps of the contactors 6 and 8 in the housing 10 from the above state, the slider 12 pushes up the contact terminals 16a and 18a of the cable, and the contact end portions 60 and 80 in the housing 10, and causes the contact terminals 16a and 18a to be respectively urged against and brought into contact with the contact end portions 60 and 80 by required pressures. In addition, the cable 14 is clamped and fixed in the connector housing 10. As shown in Fig. 6, in this state, the contact terminals 16a of the cable are pushed up by the flat surface of the thick portion 22 of the slider, and are urged against and brought into contact with the contact end portion 80 located at a higher position in the connector. The contact terminals 18a of the cable are pushed up by the horizontal flat surface of the thin portion 21 of the slider, and are urged against and brought into contact with the contact end portion 60 located at a lower position in the connector. A cable portion between contact points with these contactors has a shape substantially conforming to the inclined surface of the slider 12. Therefore, the cable 14, held and fixed in the connector housing 10, can maintain its smooth shape along the indentation 20 of the slider 12 without being bent. Therefore, the contact terminals 16a and 18a, and the lead wire portions 16b and 18b of the cable 4 can be free from damage, and an electrical disconnection cannot occur. As has been described above in detail, according to the connector of the present invention, the contact terminals of the cable are alternately arranged in a staggered form, and the contactors in the connector housing are also arranged such that their contact end portions are alternately arranged in a staggered form. Therefore, each contact terminal can be excellently electrically connected even if pitches between the contact terminals decrease along with the development of a high-density, small-sized printed circuit board to be connected to the connector. At the same time, in the contactors alternately arranged at front and rear portions in the connector housing, their heights with respect to a direction to be brought into contact with the cable are different from each other, and an indentation is formed in the slider in association with the difference of the height. Therefore, the size of the connector housing itself and the moving distance of the slider with respect to the connector housing can be decreased. Thus, not only is the size of the connector reduced, but also insertion of the cable into the connector housing can be smoothly performed, and the cable can be brought into electrical contact with the connector with high reliability.

Claims: An electrical connector (2) for use with a flat flexible cable (14) with a plurality of conductors; said connector (2) comprising: a housing (10) having a space (4) therein accessible through an opening in one side (11) the space (4) serving for receiving said flexible cable (14); a plurality of first and second electrical contactors (8, 6) arranged alternately side by side within said space (4), each of said electrical contactors (8, 6) having a contact end portion (80, 60) for electrically contacting one of said conductors of said flexible cable (14), all of said contact end portions (80, 60) extending along said space (4) toward said opening in the housing (10), in a direction opposite to that in which the cable (14) is received with the distance over which the contact end portions (80) of all the first contactors (8) extend being greater than the distance over which the contact end portions of all the second contactors (6) extend and a slider (12) for inserting said flat flexible cable (14) through said opening and into the space (4) of the housing to contact said first and second electrical contactors (8, 6); characterised in that each of said contact end portions (80, 60) also extends across said space (4) perpendicularly to the direction in which the cable is received to a predetermined depth, with each of the contact end portions (80) of said first contactors (8) extending across said space (4) to a depth which is less than the depth to which each of the contact end portions (60) of the second contactors (6) extend and said slider (12) includes a forward end portion (21) having a thickness which substantially corresponds to the transverse depth of the gap left in space (4) by all of the contact end portions (60) of said second contactors (6) and a rearward portion (22) having a thickness which substantially corresponds to the transverse depth of the gap left in space (4) by all of the contact end portions (80) of said first contactors (8), thereby providing for electrical contact between each of said contact end portions (80,60) and a predetermined conductor of said flat flexible cable (14). An electrical connector according to Claim 1, wherein said first and second electrical contactors (8, 6) also have U-shaped portions (81, 61) disposed in said space (4), said first and second contact end portions (80, 60) alternately forming one arm of each of said U-shaped portions (81, 61) of adjacent electrical contactors (8, 6) with the forward end portion (21) of said slider being adapted to slide within said U-shaped portions (81, 61) when inserted into said space (4) of the housing (10). An electrical connector according to Claim 1 or 2, wherein said slider (12) is provided with an indentation (20) which defines substantially said forward end portion (21), the depth of said indentation (20) being greater than the thickness of said flat flexible cable (14). A connector according to Claim 3, wherein the indentation (20) provides a smoothly inclined surface facing the contact end portions (80, 60) and merging the forward end rearward portions (21, 22) of the slider (12). A connector according to any one of Claims 1 to 3, wherein the first and second contactors (8, 6) each have contact surfaces (82, 62) located opposite the respective. contact end portions (80, 60).

Inventors: ARAI CHIAKI C O DU PONT JAPAN, YODOGAWA AKIHIRO C O DU PONT J, ARAI, CHIAKI, C/O DU PONT JAPAN TECHNICAL CENTRE, YODOGAWA, AKIHIRO, C/O DU PONT JAPAN TECHN.CENTRE
Applicants: CONNECTOR SYSTEMS TECH NV, CONNECTOR SYSTEMS TECHNOLOGY N.V.
Application year: 1990
Main classification: H01R9
IPC codes: G11B23, H01R12, H01R24