US 3840840 A
Description (OCR text may contain errors)
United States Patent 1191 Worth Oct. 8, 1974 1 FLAT CONDUCTOR CABLE CONNECTOR  Inventor: Sidney V. Worth, Flourtown, Pa.
 Assignee: Continental-Wirt Electronics Corporation, Warminster, Pa.
 Filed: Aug. 10, 1973  Appl. No.: 387,486
Primary ExaminerPaul R. Gilliam Assistant Examiner- Robert A. Hafer I Attorney, Agent, or Fir mvEdelson and Udell 5 7] ABSTRACT A connector for a multi-conductor insulated flat conductor cable tape having metal contact members which are respectively anchored to the several flat ribbon conductors of the cable, each said contact member having paired coplanar conductor-piercing prongs which are adapted to be so clinched together as to completely embrace and make electrical contact with a pierced segment of the insulated ribbon conductor to which it is anchored along a line which extends parallel to the longitudinally extending center line of the conductor. The contact member is stamped from a thin sheet of electrically conductive metal which is of a thickness much less than the width of the ribbon conductor to which it is anchored and since the clinching of the contact member to the conductor is in line with the conductor, i.e., lengthwise thereof, the connector may be employed for cables having very low center to center distances between the conductors thereof. Each contact member is provided with a'terminal for connecting the conductor to electrical circuitry. Also, the connector is provided with strainrelief means which prevents transmittal of disruptive strains to the interconnected conductor and contact.
14 Claims, 11 Drawing Figures PATENTED 81974 sum 1m 3 PATENIHJBET w M 3.840.840
sum 20$ 3 v FLAT CONDUCTOR CABLE CONNECTOR This invention relates generally to electrical connectors and more particularly to connectors for multiple conductor insulated cables of the so-called flat conductor cable type to provide the same with contact terminals for electrically connecting one or more of the several conductors of the cable to the components of an electrical circuit.
A relatively recent development in the electrical conductor art is the provision of a flat conductor cable tape which consists of a plurality of laterally spaced foil ribbons of copper or other electrically conductive material disposed in parallel relation in a common plane and encapsulated in a covering of insulating material, such as polyester or other plastic, which is suitably bonded to and about the several conductor ribbons of the cable. Such cable tapes are available in long lengths which can be cut into shorter lengths as required and may have an overall thickness of 0.015 inch for foil of 0.002 inch thickness and be of any width depending upon the number, spacing and width of the individual ribbons contained in the tape. While the width of the foil ribbon for any given cable is generally on the order of 0.05 inch, it may be more or less than this dimension depending upon the use specifications for the cable tape.
Heretofore and prior to the present invention, the known constructions of connectors for flat conductor cable tapes generally have had the disadvantage of limiting the number or density of contacts which may be disposed with adequate spacing therebetween in an inline relation, i.e., with all of the contact elements disposed in insulated non-interfering relation along a single line extending lengthwise of the connector, this being due primarily to the fact that the connection between each of the cable conductors and its associated contact element was of an over-all width which equalled or exceeded the width of the conductor itself.
Having in mind the foregoing, it is among the principal objects of the present invention to provide an improved construction of a connector to facilitate easy and rapid connection of the cable conductors to electrical circuitry and various electronic components.
More particularly, it is an important object of the invention to provide a connector contact member which is adapted to so pierce the foil ribbon conductor of the cable and be staked about segments of the conductor foil in a plane which intersects and extends longitudinally along the length of the conductor as to provide not only a firm and secure attachment of each such contact element to its associated conductor but also an increased area of electrical connection between each of the conductors and its contact element for lowering the resistance and thereby increasing the electrical conductivity of each such connection,
Also, it is a further important object of the invention to provide a connector for a flat conductor cable tape having contact elements which are adapted to respectively pierce and be staked about segments of the cable conductors in such manner that the overall-breadth of the connection between each conductor and its associated contact element is not appreciably greater than the thickness of the electrically conductive metal of which the contact element is formed, in consequence of which the integrity of the conductor is fully maintained in respect to all of its physical and electrical properties.
More specifically, it is an object of the invention to provide a connector having contact elements which are of a thickness substantially less than the width of the conductor itself whereby the several contact elements which are respectively secured to the flat conductors of the cable tape may be disposed in closely spaced parallel planes extending lengthwise of the cable conductors to provide as aforesaid an increased density of in-line contacts per unit of length of the connector for a cable having a very low center to center distance between the spaced conductors thereof.
Still another object of the present invention is to provide a contact member for a connector for cable tape 'of the flat conductor type which is adapted to effect a mechanically secure and good electrical connection between the contact member and its associated foil ribbon conductor even though the conductor is of an extremely narrow width, whereby the connector may be effectively employed in conjunction with-cable tapes having only low center to center distances between the several conductors thereof.
Still another object of the invention is to provide a connector for a flat-conductor cable having selfcontained means for precluding the imposition of any strains or'stresses upon the connections between the several conductors of the cable and their respectively associated contact elements.
Other objects and advantages of the present invention will appear more fully hereinafter it being understood that the invention consists substantially in the combination, construction, location and relative ar-' rangement of parts, all as described in the following specification, as shown in the accompanying drawings and as finally pointed out in the appended claims.
In the accompanying drawings:
FIG. 1 is a perspective view showing the connector of the present invention attached to one transversely cut end of a fiat conductor cable;
FIG. 2 is a greatly enlarged cross-sectional view through the cable-attached connector as taken along the line 22 of FIG. 1;
FIG. 3 is a detail sectional view as taken along the line 3-3 of FIG. 2;
FIG. 4 is a perspective view, greatly enlarged, of a contact element as constructed in accordance with and embodying the principles of the present invention.
FIG. 5 is a transverse sectional view through the connector as taken along the line 5-5 of FIG. 1;
FIG. 6 is an exploded view showing in perspective the several components of the assembly shown in FIG. 1;
FIG. 7 is a view, partly in section, showing the press for staking the contact elements to the cable conductors, one of the contact elements being shown positioned in said part prior to initiation of the staking operation; i i
FIG. 8 is a view of the press shown in FIG. 7 after completion of the. stakingoperation withthe contact elements shown fully staked to a conductor of the cable tape;
FIG. 9 is a longitudinal sectional view illustrating application of connectors constructed in accordance with the present invention for use as male and female plugs for interconnecting separate lengths of flat conductor cable tape, the connectors in this instance having included therein contact elements of a modified form;
FIG. is a perspective view of still another modified form of the contact element; and
FIG. 11 is an enlarged view of the portion inscribed within the broken line oval 11 of FIG. 8.
Referring now more particularly to FIGS. 1 to 6, it will be observed that the connector of the present invention, designated generally by the reference numeral 10, is shown applied to a flat conductor cable tape 11 which includes a plurality of coplanar laterally spaced foil ribbons 12 of copper or other suitable electrically conductive material disposed in parallel relationand encased in a common covering 13 of insulating material, such as polyester or other penetrable plastic material. The connector 10 which is clamped to the cable tape cross-wise thereof as hereinafter described is in the form of an assembly which includes an elongated vvcontact-supporting plate 14 overlying one face of the cable tape and a coverplate 15 of corresponding length overlying the opposite face of the tape. The connector is provided with a plurality of contact elements 16 (one form of which is illustrated in FIG. 4) which are respectively mechanically and electrically connected to the several foil ribbon conductors 12 of the cable.
As shown in FIG. 4, the contact elements 16 are typically formed as stampings out of a relatively thin but suitably hard and durable sheet material having good electrical conductivity properties, such as. berylium copper or phosphor bronze. Preferably, the thickness of the stamped contact element is 0.012 inch, which thickness may vary somewhat subject only to the condition that it is substantially less than the width of the conductors to which the contact elements are connected. The contact elements 16 are generally of a shape having a freely extending elongated electrical terminal stem 17 to provide for the contact a terminal which may be formed into any suitable shape, as for example, a flat terminal as shown or either a male or female prong-type connector as may be desired. The contact terminal stem 17 is provided at its conductoranchoring end with a transversely extending, rectangularly shaped part 18 which is furcated as shown to provide a central pair of sharply pointed conductor piercing tines 19-19 and a pair of sharply pointed relatively short conductorpiercing tooth-like prongs 2020 respectively disposed in spaced relation to either side of the tines 1919. Also, the opposite sides of the anchoring part 18 of contact 16 are respectively lanced to provide tabs 2121 which are oppositely bent out of the plane of the contact part 18 as shown in FIG. 4. It will be observed that whereas the tines 19-19 are of a length substantially greater than the 'overall thickness of the cable tape, the prongs 20--20 are each of a length such that when projected through one insulated surface of the cable they adequately pierce and extend completely through the foil ribbon metal conductor 12 of the cable.
It will be noted also that the tines 1919 and the tooth-like prongs 20-20 are all co-planar with the part 18 of the contact and its terminal stem 17 so that when the contacts are nested in the connector 10, as shown in FIG. 1, they are respectively disposed in parallel planes which extend lengthwise of the several conductors to which the contacts are anchored. Since the contacts are each of a thickness appreciably less than the widths of the conductor ribbons 12, the latter may contact part 18.
be of relatively small width to provide for a low center to center distance between the laterally spaced conductors and thereby allow for an increased density of inline contacts per unit of length of the connector 10. Preferably, the several contact 16 are disposed in parallel planes which are respectively coincident with the longitudinally extending center lines of the conductors, but it will be understood that this is not essential so long as the contacts are uniformly spaced with reference to said center line with each contact located within the marginal side edges of its associated conductor.
The contacts 16 are frictionally held nested in the plate 14 of the two-part connector assembly 10. To this end, the connector plate 14 is provided with a plurality of parallel slits 22 spaced-in parallel relation lengthwise of the connector, each such slit extending through the full depth of the plate 14 and having an upper portion 23 of a transverse dimension sufficient to permit the free projection therethrough of the contact terminal strip 17 and a lower portion 24 of an enlarged transverse dimension to permit the seating therein of the When the contacts 16 are respectively inserted into the several slits 22 of the base plate 14 of the connector 10 as shown best in FIGS. 6 and 7, they are frictionally held therein against displacement by engagement of the tabs 2121 with opposite wall surfaces of the slits, leaving fully exposed only the central pair of the pointed tines l919 and prongs 2020.. With the contacts 16 thus fitted in the several slits 22 of the base plate 14 and disposed with their conductor-piercing points extending freely from the plate 14 the contacts mechanically and electrically connecting each of them to a separate one of the cable conductors.
This anchoring of the cable to the contacts while fitted in the plate 14 of the connector may be effected by any suitable, means, preferably as by a press which as is'illustrated in FIGS. 7 and 8. With the plate 14 and its assembly of contacts positioned upon a suitable support 25, which may be part of the press itself, and disposed with the conductor-piercing points of the contacts presenting upwardly, the multiple-conductor cable 10 may then be anchored to the contacts by the vertically reciprocable ram 26 of the press which is provided with suitably shaped recesses 27 in its bottom end to oppositely roll the tines 19-19 about and into the top surface of the insulated cable tape. As the tines 19-19 and the outwardly spaced prongs 2020 of each contact 16 pierce the insulated foil ribbon conductor 12 to which it is to be anchored, the tines l9l9 are so staked or clinched around the conductor as best shown in FIG. 8 as to bring the pointed extremities thereof respectively in substantially coplanar engagement with the pointed extremities of the relatively short prongs 20--20, thereby pinching thin longitudinal sections of the conductor ribbons between the staked-over tines and their respectively associated prongs. It will be observed that the clinched-together tines and prongs of each contact remain substantially co-planar in a plane which is normal to and extends lengthwise of the flat conductor ribbon and that the tips Each contact thus provides two longitudinally spaced coplanar areas 28 of clinched electrical connection to its associated ribbon conductor. Actually, as the tines 19-19 slice through the insulated conductor cable from one side thereof and are rolled back into the cable conductors from the opposite side of the cable for respective engagement with the prongs 20-20 which have also penetrated the cable conductors, the foil ribbon conductor in each of the areas 28 thereof is compressed or compacted tightly between the conductorclinching parts of the contact, thereby lowering the resistance value of the two electrical connections of each contact with its associated ribbon conductor. Thus, there is effectively provided firm and secure mechanical connection between the contact and conductor with maximum electrical conductivity therebetween. Since the co-planar conductor-piercing points of the contact penetrate the insulated conductor lengthwise thereof along a single line which is spaced inwardly from opposite side edges of the foil ribbon they do not tend to sever or otherwise weaken the conductor, but instead insure that the integrity of the conductor throughout the regions thereof which are pierced by and connected to the contact points is effectively maintained to provide a good electrical and mechanical connection between the conductor and its associated contact.
With the multiple-conductor cablevtape anchored to the contacts 16 of the connector as above described, it
only remains to secure the cover plate 15 to the contact-supporting plate in covering relation to the anchored end of the cable tape. To this end the plate 15, as best shown in FIG. 6, is provided in the face 29 thereof which mates with face 30 of the plate 14 with a plurality of longitudinally spaced parallel recesses 31 each of a dimension to accommodate therein the clinched over extremities 32 of the cableconnected contacts 16 when the two connector parts 14 and 15 are secured together, as by screws 33 threaded into nuts 34 molded or otherwise provided at opposite ends of the connector, which latter ends respectively project beyond the marginal ends of the cable tape. Alternatively, in lieu of a plurality of spaced recesses 31, the cover plate 15 may be provided with a single recess of a length sufficient to commonly accommodate therein the clinched extremities of all of the contacts 16 mounted in in-line relation in the connector part 14 as previously described. Upon such securement together of the connector parts 14 and 15, as by the screws 33 or otherwise, the marginal side portions of the cable tape 1 1 are securely clamped between the mating faces of said parts thereby retaining in secure position the several contacts respectively anchored to the cable conductors with their terminal strips projecting from the assembled connector 10 as shown best in FIG. 1.
It is desirable to provide a strain relief for the cable tape and thus the cable connector of the present invention is provided with a self-contained means for precluding the imposition of any strains or stresses upon the connections between the several conductors of the cable and their respectively associated contacts. To this end, it will be noted that the plate 14 is provided along one of its longitudinally extending sides with a depending flange 35 which is spaced from the corresponding side of its associated cover plate 15 a distance equal to the thickness of the cable tape disposed therebetween. The end portion of the cable tape 11 which is clamped between the connector parts 14 and 15, as see in FIG. 2, is pre-set to a shape which, when the tape is anchored to the contacts 16, includes a Z-shaped portion 36 adapted to be snugly accommodated within the correspondingly shaped cable space formed between the flanged plate 14 of the connector and its cover plate 15. When the plate 15 is secured to covering relation to the cable, the Z-shaped bend in the latter serves to relieve the contact-to-cable conductor connections of strains and stresses which might be disruptive of the connections.
Also, as shown in the drawings, the cover plate 15 is preferably provided along the side thereof which is opposite that which includes the strain relief flange 35 with a flange 37 which overlaps the corresponding side of the plate 14 and serves'as a protective shield against exposure of the cut end of the cable tape to which the connector is attached.
FIG. 10 shows a modified form of a contact 16a wherein its furcated part 18a thereof is centrally provided with a single lanced tab 38 instead of the two end tabs 21 of the previously described contact. In all other material respects the contact 16a is similar to and employed in the same manner as the contact 16.
FIG. 9 illustrates still another modified form of a contact 16b wherein its furcated part 18b is provided with an endwise extending terminal stem adapted to project outwardly from one side of the cable connector as a linear extension of the end of the cable conductor to which the contact is secured. This FIG. 9 also illustrates the use of two connectors 39 and 40 each employing such contacts 16b having terminal stems which are adapted to be interengaged to form a completed electrical connection between two separate sections 11a and 11b of a multiple flatconductor cable. The connector 39 for the cable section 1 1a comprises a pair of elongated plates 41 and42 which coact in the same manner as the plates 14 and 15 of the previously described connector to clamp the cable section 11a therebetween. It will be noted, however, that the plate 41 is provided in its cable-engaging face with open-topped contact-receiving slits 43 which extend across the full width'thereof instead of vertically as in the plate 14, which slits 43 are disposed in spaced parallel relation along the length of the connector plate 41 to respectively accommodate therein the contacts 16b which are staked to the several conductors of the cable in the same manner as those previously described. The cable section 11a so disposed in the connector part 41 is then clamped in secured position by the mating connector part 42, which latter part is provided with a flange 44 which coacts with the part 41 in the same manner as the strain relief means of the connector 10 previously described.
The contact-receiving plate 41 of the connector 29 additionally includes as an integrally molded part thereof a laterally extending socketedpart 45 for housing therein the aforementioned several terminal stems 17b of the contacts 16b which strips in the case of the connector 39 are shaped or rolled into cylindrical or semi-cylindrical form to serve as female connector elements. The contacts 16b are held against displacement from the socket 45 by detents 46 sprung outwardly of the terminal strips 17b to present their free ends 47 in abutting engagement with an internal shoulder or stop 48 formed in the rear end of the molded extension 45. This extension 45 is provided at its outer end with one or more openings 49 to permit insertion therein of male terminals for registration with and connection respectively to the female connecting elements of the cable connector 39 which is in the form of and used as a female connector plug.
The complemental connector 40 for the cable section 1 lb also includes a pair of elongated plates 50 and 51 which differ from those of the connector 39 only in the following respects. First, the laterally extending terminal stems of the contacts 17c are shaped or'rolled into the form of male connector pins for respective insertion into and electrical engagement with the female connector elements of the connector 39. Second, the plate 50 of the connector 40 for the cable section 11b includes as an integrally molded part thereof a laterally extending part 52 which commonly encloses the several male connector pins of the connector 40 and is socketed at its free end to receive therein the molded socketed part 45 of the connector 39. Thus, when the parts 45 and 52 of the connectors 39 and 40 are interfitted one within the other they conjointly provide a protective sheath of insulation for the interengaged male and female elements of the cable connectors.
It will be understood, of course, that the cable coupling arrangement shown in FIG. 9 is illustrative of but one of various arrangements in which may be employed contacts and cable connectors constructed in accordance with and embodying the principles of the present invention. Also, the contacts per se are subjected to other variations and modifications which may be made from time to time without departing from the essential principles or real. spirit of the invention and accordingly it is intended to claim the same broadly, as well as specifically, as indicated by the appended claims.
What is claimed as new and useful is:
1. An electrical connector for an insulated ilat cable having a plurality of flat ribbon conductors embedded in the cable insulation in coplanar side by side spaced relation comprising an insulated structure secured to the cable in transversely extending relation to the conductors thereof and a plurality of electrically conductive metal contact members mounted in said structure in spaced parallel planes respectively extending perpendicular to the flat plane of the cable and lengthwise of the conductors thereof, each of said contact members having an outer terminal part for connection to an electrical circuit or component thereof and an inner retention part for retaining said contact member in said structure, said retention part having extending from one edge thereof .at least one pair of spaced-apart pointed elements for piercing a ribbon conductor of the insulated cable, one of said elements being of a length substantially exceeding the overall thickness of the insulated cable and so reversely bent and clinched about the cable as to substantially close the gap between the points of said spaced-apart elements whereby the latter conjointly embrace and make electrical contact with a longitudinally extending narrow segment of the ribbon conductor pierced thereby.
2. An electrical connector as defined in claim 1 wherein said pair of pointed elements constitute integral extensions of and are commonly disposed in coplanar relation to said retention part of each said contact member and wherein said elements are of a uniform thickness substantially less than the width of the ribbon conductor pierced thereby whereby the connector may be applied to a cable having a low center to center distance between the conductors thereof and thereby increase the density of contact members per unit length of the connector.
3. An electrical connector as defined in claim 1 wherein said connector structure is provided along the length thereof with a plurality of slits disposed in spaced parallel relation for respectively receiving therein said contact members with the terminals thereof projecting externally from one side of the structure.
4. An electrical connector as defined in claim 1 wherein said retention part of each said contact member is provided with two of said pairs of spaced-apart pointed elements all disposed in a common plane extending lengthwise of a cable conductor pierced thereby whereby to-provide each said conductor with a pair of longitudinally spaced coplanar areas of clinched electrical connection with its associated contact member.
5. An electrical connector as defined in claim 1 wherein said one edge of said contact member retention part extends lengthwise of the cable in contact with one insulated surface thereof along a line disposed intermediate the marginal side edges oft'he ribbon conductor pierced by said elements and wherein said elements effectively pinch therebetween said longitudinally extending segment of the pierced ribbon conductor.
6. In a connector as defined in claim 1 wherein said terminal part extends from said retention part in a direction opposite that of said pointed elements.
7. In a connector as defined in claim 1 wherein said terminal part extends from said retention part in a direction normal to that of said pointed elements.
8. In a connector as defined in claim lwherein said insulated structure is provided with spaced parallel recesses extending lengthwise of the cable in which said contact members are respectively nested.
9. In a connector as defined in claim 1 wherein said insulated structure includes a multi-slitted base member and a mating multi-recessed cover member adapted to be securedtogether with the slits of said base meme ber in coplanar registry respectively with the recesses of said cover member and wherein a multiconductor cable clamped between said base and cover members with the several ribbon conductors of the cable each having clinched thereto one of said contact members nested in the slitted base member.
10. In a connector as defined in claim 9 wherein one of said mating members of said insulating structure is provided with a depending flange disposed in spaced parallel relation to one side of the other of said mating members to provide an angularly shaped space between proximate surfaces of the mating members in which to receive a correspondingly shaped section of the cable whereby to provide a strain relief means for the cable clamped in said structure.
11. In a connector as defined in claim 9 wherein said base and cover members of said insulating structure are complementally shaped lengthwise-thereof to seal the transversely cut end of the cable clamped therebetween.
12. An electrical connection comprising in combination an insulated flat cable having a plurality of flat ribbon conductors embedded in the cable insulation and a contact member for each of a selected number of said conductors,-said contact member being formed of a stamping of thin sheet metal which includes a body portion having extending from one edge thereof an elongated terminal strip and from another edge thereof at least one pair of conductor-piercing tooth-like elements having pointed extremities arranged in spaced tandem relation in the plane of said body portion, one of said paired elements being of a length substantially longer than and the other being of a length not exceeding the overall thickness of its associated insulated conductor, each of said paired elements being projected through said insulated conductor with said body portion of said contact member extending lengthwise of the conductor with the longer one of said elements reversely bent back into the opposite side of the insulated conductor to present its pointed extremity into closely adjoining relation to the pointed extremity of the shorter one of said elements and thereby encircle and pinch between said elements a longitudinally extending narrow segment of the ribbon conductor.
13. An electrical connection as defined in claim 12 wherein said body portion of each said contact member is provided with a first pair of said longer length conductor-piercing elements and a second pair of shorter length elements all disposed in the fiat plane of said body portion and in spaced tandem relation.
14. An electrical connection as defined in claim 13 wherein said first pair of longer length conductorpiercing elements are disposed centrally between said second pair of shorter length elements and are adapted respectively to be clinched to the shorter elements in embracing relation about a pair of longitudinally spaced segments of the conductor lying in a common plane extending vertically with respect. to the plane of said conductor in parallel relation to the longitudinal center line of the conductor.