Connector used for flexible flat cable

Abstract: A connector used for a flexible flat cable (100), comprises: a housing (10) having a plurality of contacts (11) mounted therein, and a cap plate (20) for capping and retaining a flexible flat cable (100) set in the housing (10). The housing (10) includes an opening (12) for receiving the flexible flat cable and a recess (13) formed substantially in the center of the opening in the longitudinal direction of the housing. Contact portions (11A) of contact portions of contacts (11) extend to the recess (13), and are mounted along the long side of the housing (10) at a predetermined pitch. The housing (10) and the cap plate (20) have latching means (14,22) for latching them to retain the flexible flat cable (100) positioned in the housing.

Description: FIELD OF THE INVENTION : The present invention relates to a small connector used for connecting a flexible flat cable to a printed circuit board (especially a flexible board), and in particular to a low-profile small connector on which multiple contacts are mounted at a short arrangement pitch. BACKGROUND OF THE INVENTION : An example of a flexible flat cable (including a flexible printed circuit (called an FPC) cable) is a ZIF (zero insertion force)-FPC connector or a connector disclosed in Utility Model Laid-open Japenese Publication 6-88083 (1994). For the first connector after the attachment of a cable a lever must be rotated in order for a cable electrode (or a conductive contact) to make contact with the contact of the connector, and special equipment is required to automate the job of assembling the cable and the connector. To eliminate the above problem, according to a method employed for the second connector, whereby a reinforcement plate (a cover) is attached to the surface of a cable and the cable with the reinforcement plate is directly assembled with the connector, the reinforcement plate engages a guide formed on the connector during the assembly of the cable and the connector to thereby position the cable correctly. However, a process for attaching the reinforcement plate to the surface of the cable can be required before the cable is assembled with the connector, and high accuracy is required for the attachment, especially for a connector whose contacts are arranged at a short pitch, so that strict control of the sizes of the parts must be exercised. United States Patent 4,936,792 discloses a connector used for flexible flat cable and having a housing with electrical contacts secured in opposing sides of the housing. A flexible flat cable is maintained in connection with the electrical contacts by a cover member which is pivotally mounted to the housing and latched to the housing by latching members. SUMMARY OF THE INVENTION : A connector according to the present invention has been developed in order to eliminate one or more of the above problems of the conventional connector. Specifically, it is one aim of the present invention to provide a flexible flat cable connector that has multiple contacts arranged at short pitches, and for which the exertion of the retention force requires only a simple operation, while taking into account the automation of the assembly of the cable and the connector. To achieve the above aim, according to the present invention, there is provided a connector used for a flexible flat cable, comprising: a housing having a plurality of contacts mounted therein, and a cap plate for capping and holding said flexible flat cable set in said housing, wherein said housing includes an opening for receiving the flexible flat cable therethrough and a recess formed in a substantially center portion of the opening along a longitudinal direction of the housing, and each of said plurality of contacts comprises a contact portion residing within the recess and a leg portion extended externally, said contacts being mounted at a predetermined pitch in the longitudinal direction of the housing, wherein said housing and said cap plate have latching means for latching the cap plate to said housing, wherein said cap plate comprises a ridge formed in a longitudinal direction thereof, said ridge being fitted in the recess of said housing when said housing and said cap plate are latched, so as to urge said flexible flat cable into conductive engagement with said contact portions of said contacts. BRIEF DESCRIPTIONS OF THE DRAWINGS : Figure 1 is a plan view showing a connector according to the present invention. Figure 2 is a side view showing the connector shown in figure 1. Figure 3 is a sectional view showing the connector shown in figure 1. Figure 4 is a perspective view showing a cover plate of the connector according to the present invention. Figure 5 is a sectional view showing a state of the connector being used. Figure 6 is a view showing a case where the connector shown in figure 1 is mounted on a printed circuit board. DETAILED DESCRIPTION OF THE INVENTION: The arrangement of the present invention will now be described by referring to one illustrated embodiment. A connector according to the present invention, which is used for flexible flat cable, comprises a housing 10 on which a plurality of contacts 11 are mounted; and a cap plate 20 for capping and retaining a flexible flat cable 100 that is positioned in the housing. In figures 1 to 3 is shown the housing of the connector of the present invention, and in figure 4 is shown the cap plate. The external shape of the entire housing is a square, and provided in the housing are an opening 12 for accepting and positioning the flexible flat cable, and a recess 13 formed substantially in the center of the opening and extending in the longitudinal direction of the housing (the ridge (protrusion) of the cap plate engages the recess with the cable positioned in between, as will be described later). The contacts are arranged at a constant pitch at the bottom of the opening in the housing and along the long sides of the housing that face each other. At this time, contact portions 1A of the contacts extend inside the recess in the housing, leg portions 11B of the contacts extend outward, and the main body between the contact portions and the leg portions of the contacts is securely fixed or embedded in grooves formed in the facing sides of the housing. In this embodiment, the contact portions of the contacts are leaf springs, which alternately project into the recess from the sides of the housing located opposite each other. The cap plate caps and holds the fexible flat cable, which is inserted into the opening in the housing, and brings conductive contact portions 100A of the flexible flat cable into contact with the corresponding contacts in the housing to provide electrical connections (see Figure 5). At this time, if the contact portions of the contacts, which are mounted on the housing, are sufficiently wide and cover the contact positions of the conductive contact portions of the flexible flat cable, precisely aligned electrical connections of the contacts and the contact portions of the cable can be obtained. The housing and the cap plate have latching means for latching them to each other, and when the two are latched, they are positioned in the housing that they hold the flexible flat cable. In the embodiment shown in the diagrams, the latching means comprises paired protrusions 22, which, as is shown in Figure 4, are formed along the short sides of the cap plate that face each other, and paired latch plates 14, which, as is shown in Figures 1 to 3, are mounted on the short sides of the housing that face each other. The latch plates each include a latch portion 14A, latch portions 14C (see Figure 1) and a base portion 14B (see Figures 1 and 2), with the first two portions being raised from the base portion. Both ends of the base portion 14B of the latch plate extend outside the housing, and are soldered, with the legs of the contacts, to conductive pads 31 (see Figure 6) on a printed board 30 (see Figure 5), for example. Grooves 14a are formed in the latch portions of the latch plate to engage the protrusions 22 on the cap plate. The latch portions 14C on the latch plate are fixed to the grooves that are formed in the short sides of the housing that face each other. A ridge 21 is formed on the cap plate in its longitudinal direction, and is fitted into the recess in the housing when the housing engages the cap plate. In Figure 6 is shown a case where the flexible flat cable connector according to the present invention is automatically mounted on a flexible printed board. As is shown, in this embodiment, an automated mounting apparatus holds and moves the housing of the connector by using a tape 40 attached to the surface of the housing. According to the connector of the present invention, since the cap plate caps and holds the flexible flat cable inserted into the opening in the housing (especially the ridge (the protrusion) formed on the cap plate that engages the recess in the housing via the cable), unlike the conventional connector, the process for attaching a reinforcement plate (cover plate) to the surface of the cable is not required. In addition, the accuracy of the positioning of the cable is not affected by the precision of the attachment of the reinforcement plate, and the engagement of the cover plate with the recess in the housing can correctly position the cable. Furthermore, when the ridge of the cap plate engages the recess in the housing via a cable, the force available for holding the cable and the strength of the connector can be increased, when compared with the conventional connector where the flat cover simply engages the housing. In addition, the thickness (the height) of the connector can be adequately reduced. Various changes to the foregoing described and shown structures would now be evident to those skilled in the art. Accordingly, the particularly disclosed scope of the invention is set forth in the following claims.

Claims: A connector used for a flexible flat cable (100), comprising: a housing (10) having a plurality of contacts (11) mounted therein, and a cap plate (20) for capping and holding said flexible flat cable (100) set in said housing (10), wherein said housing (10) includes an opening (12) for receiving the flexible flat cable (100) therethrough and a recess (13) formed in a substantially center portion of the opening (12) along a longitudinal direction of the housing (10), and each of said plurality of contacts (11) comprises a contact portion (11A) residing within the recess (13) and a leg portion (11B) extended externally, said contacts (11) being mounted at a predetermined pitch in the longitudinal direction of the housing (10), wherein said housing (10) and said cap plate (20) have latching means for latching the cap plate (20) to said housing (10), wherein said cap plate (20) comprises a ridge (21) formed in a longitudinal direction thereof, said ridge (21) being fitted in the recess (13) of said housing (10) when said housing (10) and said cap plate (20) are latched, so as to urge said flexible flat cable (100) into conductive engagement with said contact portions of said contacts (11). The connector according to claim 1, wherein said latching means comprises a pair of outwardly projecting protrusions (22) formed at opposed short sides of said cap plate (20) and a pair of latch plates (14) formed at opposed short sides of said housing (10), wherein the latch plates (14) each include a groove (14a) for engaging with the protrusions of said cap plate (20). A connector according to claim 1 or claim 2, wherein the contact portion (11A) of each of the contacts (11) mounted in said housing (10) sufficiently covers contact positions of conductive contact portions (100A) of the flexible flat cable (100).

Inventors: SUZUKI MASAO, SUZUKI, MASAO
Applicants: THOMAS & BETTS CORP, THOMAS & BETTS CORPORATION
Application year: 1998
Main classification: H01R12
IPC codes: H01R12, C07K14