Background of the Invention
1 Field of the Invention
The invention relates to terminal modules, or modular interconnect terminals, and to components of such terminal modules for use in establishing interconnections between parts of telecommunication systems and the like. More particularly, it relates to unit frames or bodies of use in electrical interconnection modules, or terminal modules and to modules formed by folding the unit frames into box-like structures. The frames are equipped with standard connectors bearing contacts and/or have contacts molded into them so that each frame supports a plurality of individual contacts. The contacts are interconnected on a selective basis by means of conductors on flexible circuit boards so that the boards are supported by the unit frames. The unit frames include regions about which they may be bent to form box-like terminal modules and include latching means which may be engaged to secure the modules as units.
Description of the Prior Art
Prior art telephone termination systems, and particularly those used in association with key telephones in business office environments, have required excessive expenditures of both time and money for installation, for maintenance and for changes in the wiring systems after they have been installed.
Examples of prior art modular connectors are shown in J. P. Nijman in U.S. Pat. No. 3,970,802 entited "Flexible Circuit Connecting Arrangement for Interconnection Modules", and assigned to the same assignee as the present invention.
In U.S. Pat. No. 3,970,802 a pair of spaced apart plates are positioned back-to-back with each plate supporting a matrix of connector terminals. The connector terminals project into the space between the back sides of the plates and are interconnected in prearranged patterns which permit interconnections between subscriber telephones and certain common equipment to be easily established or altered by engaging mating connector contacts with the contacts at the front sides of the respective plates. A flexible plastic sheet bearing a printed circuit arranged in the desired pattern enables the ready interconnection of the connector terminals between the spaced apart plates, thereby providing a flexible and efficient means for interconnecting the connector terminals. However, using the apparatus shown in Nijman it is necessary to separately fabricate the plates and to separately handle the plates and the printed circuit boards in order to establish connectors between contacts in the plates. It is then also necessary to secure the plates and the printed circuit together in the spaced apart relationships by means of spacers, nuts and bolts. Therefore, to produce the Nijman apparatus a considerable expenditure of time and money is required and the resulting apparatus is unduly complex.
Summary of the Invention
In view of the foregoing, a primary object of the present invention is to provide improved and more economical terminal unit frames and terminal modules for use in telecommunication systems and the like. One object is to provide terminal unit frames with substantially coplanar panels supporting contacts for interconnection by soldering from a common direction, with the frames being thereafter foldable to place the panels in a spaced-apart back-to-back relationship. It is a further object to provide terminal unit frames and terminal modules of simplified construction which at the same time enable a reduction in the possibilities for errors in the interconnections through the modules. It is an additional object to provide terminal modules which may be more readily assembled than the modules available heretofore. It is yet an additional object to provide terminal modules enabling greater flexibility in the number and kinds of contacts which may be supplied and in the interconnections between contacts.
To attain the foregoing and related objects, unit frames or bodies are provided with hinge regions about which they may be folded and with pockets, or receptacles, into which electrical contact elements may be fitted. For use as modular interconnect modules, the bodies are fitted with a plurality of electrical contacts in respective front and back panels forming the bodies. The electrical contacts may be supplied to the frames by molding the contacts into the plates or by placing individual contacts or standard connectors bearing contacts into prepared sockets in the plates. Connections between contacts in the front plate and contacts in the back plate are completed by a flexible printed board having a desired conductive pattern on at least one face or by a plurality of individual conductors. Terminal modules in accordance with the invention are formed by folding the unit frames through angles of 90 degrees in three preprepared places. The frames are held in a folded four-sided box configuration by locking elements or spigots extending from an edge of the back plate to engage holes near one edge of a front plate.
Brief Description of the Drawings
The above mentioned and other features and objects of this invention and the manner of obtaining them will become more apparent, and the invention itself will be best understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view of a flat plastic piece suitable for use as the unit frame of a terminal module in accordance with the invention,
FIG. 2 is a side view of the plastic piece in FIG. 1, taken along line II--II, and showing additional elements including connectors and contact elements in place together with a printed circuit board,
FIG. 3 is a side view similar to FIG. 2, taken along line II--II of FIG. 1, but showing other connectors and contact elements, and FIG. 4 is a side elevational view of a terminal module according to the invention in its finished state.
Description of Preferred Embodiments
Turning to FIG. 1, an essentially flat plastic plate of piece, which may be used as a unit frame, is indicated at 10. The plastic piece, or unit frame, may be an integral sheet or thermoplastic which has been moulded or otherwise formed to include planar and rectangular members or panels 12 and 14 which are interconnected between their edges 22 and 24 by a plurality of interconnecting struts, posts or standards such as 16, 18 and 20. A series of spaced cantilever struts 26, 28 and 30, which in a preferred embodiment are aligned with the struts 16, 18 and 20, are extended from the edge 32 of the plate 14. The plates may be called the first panel or back panel 12 and the second panel or front panel 14 for purposes of identification.
Cutouts, or slots, 34a, 34b, 34c etc. are provided in each plate, or unit frame, adjacent to the sides of each of the struts 16, 18, 20, 26, 28, 30 to extend the struts into the plate. Bevel cutouts, identified as 36a, 36b, 36c etc. in FIG. 2, are formed in each strut near the juncture of the strut with a plate to leave a narrow neck portion 38a, 38b, 38c etc. and thus provide hinge areas or hinge means. The struts may be folded about each of the hinge means by a full 90 degrees to form corners of the structure as shown in FIG. 4. Ribs 40a, 40b, 40c etc., formed preferably of plastic material integral to the plate 10, extend along each of the struts and extend out from the struts in a direction orthagonal to planes parallel to the plates and struts. The ribs 40a, 40b etc. give support for the struts and make the assembly of FIG. 4 more rigid.
Locking or latching means integral to the plate 10 are provided to enable the assembly to be locked in the position of FIG. 4. The locking means includes protrudences 42a, 42b and 42c, which may be called retention spigots, integral to the corresponding projecting cantilever struts or standards 26, 28, 30. Each of the protrudences is received and held by one of a plurality of appropriately positioned apertures 44a, 44b, 44c spaced along one edge of plate 12. The spigots 42a-42c are each of conical shape for easy entrance into the appropriate aperture. A portion 46a, 46b or 46c of reduced cross section is located behind the wide portion of each spigot and shoulders 48a, 48b, 48c and 50a, 50b, 50c form bounderies of sections 46a, 46b, 46c which engage the plate around apertures 44a, 44b, 44c and hold the plates in the back-to-back relationship of FIG. 4.
In FIG. 1, contact pockets to receive contacts are indicated in the front panel 12 at 52. These contact pockets, as preformed units, may be inserted into a hold at 54 in the front panel 12 or may be molded as a part of the front panel. Similarly, openings 56, 58 in the back plate 14 can be used to support a variety of connectors; or in preferred instances, receptacles for contacts may be formed as the plate 14 is made, and contacts may then be inserted in the receptacles. Suitable connectors are indicated at 60 and 62, 64, 66.
FIG. 2 is a side view in partial section of a plastic piece, taken along the lines II--II of FIG. 1, showing connectors and contact elements in place and a printed circuit board PC secured by solder or the like at 53 and 55 in position against the contact elements. Exemplary contact pockets 52 are shown in position in the front plate 12. As indicated above, preprepared pockets, or assemblies of pockets, may be inserted into an opening in plate 12 or they may be molded as part of plate 12, requiring then that contact elements be inserted as a manufacturing step for terminal modules in accordance with the present invention. Contact elements at 70 are oriented in a common direction and supported by substantially coplanar panels 12 and 14 to enable electrical connection to the printed circuit board PC through soldered points at 53 or the like as well as provide mechanical support between printed circuit board PC and panel 12. Interconnection of the contact elements in the flat panels and the flexible printed circuit board is accomplished by the application of solder from a common direction.
Separate connectors 60 are indicated to be present in the openings, 56, 58 of back plate 14. Here also the connectors 60 may be molded in a preferred example into plate 14 and the contact elements may be inserted as a step in manufacturing terminal modules in accordance with the invention. If separate connectors are employed at 60 they may be standard connectors shown in the aforementioned U.S. Pat. No. 3,970,802. Contact elements at 72 provide electrical connections to the printed circuit board PC as indicated by solder at 55 as well as mechanical connections between PC and back plate 14.
FIG. 3 is a side view of a plastic piece much like the view shown in FIG. 2. In FIG. 3, a plurality of connectors is indicated at 62, 64, 66 which may be "57 series connectors" produced by the Amphenol Division of Bunker Ramo Corporation, the assignee of the present invention.
FIG. 4 is an illustration of a terminal module assembled for use in accordance with the invention. In this view, the embodiment of the invention shown in FIG. 3 is shown folded and locked in position by interaction of the retention spigots 42a, 42b, 42c in the respective apertures 44a, 44b, 44c.
Preparation and assembly of the terminal module of FIG. 4 involves a number of steps including the preparation of a piece of flexible material as shown in FIG. 3 by casting, cutting, drilling and the like to provide plates 12 and 14; contact pockets 52; struts 16, 18, 20, 26, 28 and 30; the retention spigots 42a, 42b, 42c, the orifices 44a, 44b, 44c; the ribs 40a, 40b, 40c, 40d etc; the bevel cutouts 36a, 36b, 36c; etc. A printed circuit board is prepared, using conventional techniques to establish selected paths between various spots on the board. The piece of material 10 is then provided with terminals incorporating contact elements and with individual contact elements which are placed in contact pockets to establish contacts 70, 72. The printed circuit board is secured by soldering or the like at points such as 53, 55 to the contacts 70, 72 to prepare the terminal module to the state shown in FIG. 3. Thereafter, the flat plastic piece with the attachment is folded about the three hinges or narrow neck portions 38a, 38b, 38c to form a box-like structure. Retention spigots 42a, 42b, 42c are inserted then in apertures 44a, 44b, 44c to lock the terminal module in the configuration shown in FIG. 4.
While the principles of the invention have been described above in connection with specific apparatus and applications, it is to be understood that this description is made only by way of example and not as a limitation on the scope of the invention.