US 3835445 A
A one piece plug for terminating a cord to connect electrically the cord to components in a telephone apparatus is constructed with features advantageous to the assembly of the cord with the plug. The plug has a base molded with a cover hinged integrally to one end of the base and in an open position. This avoids the alignment of the cover with the base during assembly with the cord. Also, the base is formed with a cord-input aperture in the one end and which advantageously circumscribes substantially the cord periphery to maintain the cord within the plug during assembly operations. A leading portion of the cord is inserted into the aperture and extended past the other end of the plug. The jacket is removed from the leading portion to expose individually insulated conductors. Then the cord is retracted and the conductors fanned out into associated troughs having the same spacing as the components. The cover is closed and bonded to the base to confine the conductors and prevent unintended lateral and longitudinal movement. Flat terminals are inserted into the base to move internal contacting portions thereof into engagement with the conductors. External contacting portions of the terminals engage associated components of the telephone apparatus when the plug is inserted thereinto.
Claims available in
Description (OCR text may contain errors)
United States Patent Hardesty Sept. 10, 1974 ELECTRICAL CONNECTING DEVICES FOR TERMINATING CORDS AND METHODS OF ASSEMBLING THE DEVICES TO CORDS Inventor: Edwin C. Hardesty, Perry Hall, Md.
Assignee: Western Electric Company,
Incorporated, New York, N.Y.
Filed: Dec. 4, 1972 Appl. No.: 311,575
U.S. Cl. 339/99 R, 339/105, 29/629 Int. Cl. HOlr 9/08, HOlr 13/58 Field of Search 339/97-99,
References Cited UNITED STATES PATENTS FOREIGN PATENTS OR APPLICATIONS 544,048 l/l965 Belgium 339/99 R Primary ExaminerBobby R. Gay Assistant ExaminerLawrence J. Staab Attorney, Agent, or Firm-E. W. Somers  ABSTRACT A one piece plug for terminating a cord to connect electrically the cord to components in a telephone apparatus is constructed with features advantageous to the assembly of the cord with the plug, The plug has a base molded with a cover hinged integrally to one end of the base and in an open position. This avoids the alignment of the cover with the base during assembly with the cord. Also, the base is formed with a cordinput aperture in the one end and which advantageously circumscribes substantially the cord periphery to maintain the cord within the plug during assembly operations. A leading portion of the cord is inserted into the aperture and extended past the other end of the plug. The jacket is removed from the leading portion to expose individually insulated conductors. Then the cord is retracted and the conductors fanned out into associated troughs having the same spacing as the components. The cover is closed and bonded to the base to confine the conductors and prevent unintended lateral and longitudinal movement. Flat terminals are inserted into the base to move internal contacting portions thereof into engagement with the conductors. External contacting portions of the terminals engage associated components of the telephone apparatus when the plug is inserted thereinto.
13 Claims, 10 Drawing Figures PATENTED SEPI 01974 SHEET 1 OF 4 PAIENTEDSEPIOIQM 3.835.445
sum 2 0r 4 PAIENTEDSEP 1 0w sum u or 4 ELECTRICAL CONNECTING DEVICES FOR TERMINATING CORDS AND METHODS OF ASSEMBLING THE DEVICES TO CORDS BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to devices for making electrical connections and to methods of making such connec- V tions, and more particularly, to devices for making electrical connections between a cord comprising flexible conductors and terminals wherein conductive terminals are combined with dielectric members to form plugs and methods of assembling the cord and the devices.
2. Description of the- Prior Art In the telephone industry, increasing use is being made of plug-type connectors on straight and retractile handset and line cords which are used between a base and a handset of a telephone and between the base and a terminal. In the presently-used plugs, a terminal is applied to each of a plurality of insulated conductors contained within a jacketed length of retractile cordage. These terminals are mounted within a dielectric structure which is attached securely to the associated cordage. The dielectric portions of the plugs, which are mounted on both ends of a length of the cordage, cooperate with receptacles in the handset and the base of the telephone to properly align the terminals of the plug with mating terminals within the components of the telephone.
One presently used plug is disclosed in US. Pat. No. 3,699,498 issued on Oct. 17, 1972. Conductors are confined in conductorreceiving troughs formed in a dielectric base by a cover bonded to the base. Flat terminals are inserted into individual grooves in the base in a side-by-side arrangement with contact portions thereof extending into engagement with the conductors. When the plug is inserted into a jack in a telephone handset, portions of terminals in the jack are received in associated ones of the grooves to engage side portions of the plug terminals.
The provisions in the just-identified plug for contacting the external component may be changed to that described in a continuation-in-part application filed on Mar. 8, 1972 in the names of E. C. Hardesty, C. L. Krumreich, A. E. Mulbarger, Jr. and S. W. Walden. There, the external contact portions of the terminal consists of an edge exposed to the exterior of a dielectric enclosure.
Of course, the terminals in the plugs are aligned with the contact elements in the telephone handset. The cord conductors in the just-described system are aligned with the terminals. In some systems, the conductors of the cord may not be spaced the same as the contact elements in the telephone. Provisions must be made for spreading out the conductors to be engaged by terminals which are aligned with the external contact elements.
A presently used plug incorporating provisions for spacing out the conductors is disclosed in U.S. Pat. No. 3,617,982 issued on Nov. 2, 1971. In this plug, a plurality of conductors are led into a back end of the plug, then the conductors are passed over the front end of the plug and connected to end portions of terminals seated on the underside of the plug.
The recent trend to the use of plug in type conductors in telephone handsets as exemplified by that shown in US. Pat. No. 3,617,982 has been accompanied by the use of fiat telephone cords. The use of flat cords lends toward increased. manufacturing economies provided that the plug is designed with regard for a flat cord system. Also, recent advances in terminal design in plugs may be adapted for use with fiat cords on a production line basis.
The prior art related to connecting electrically a plug to conductors held together in a flat configuration is shown for example in US. Pat. No. 2,929,043. There a twin-lead antenna cable is led in through an opening formed between a body and a separate hinged cover plate. The cover plate is provided with facilities for engaging and pressing the cable into electrical contact with converging toothed contact plates.
Also available is a solderless wire connector (US. Pat. No. 3,5 76,5 l 8) containing a slotted resilient metal contact plate. The plate is transversely supported within a base contoured to support conductors to be connected. The base has a hinged cover and a collar which cooperates with a collar on the cover to provide strain relief for the conductors when the cover is closed.
SUMMARY OF THE INVENTION This invention provides a device for making electrical connections. The device can be fabricated by using conventional molding techniques and can be assembled to a cord before the cord is heat treated to achieve retractile properties. Methods are provided for assembling plugs to conductors and for establishing electrical connections between the conductors and associated terminals.
An electrical connecting device which embodies the invention is molded to include a base with a cover hinged integrally with the base and in an open position. The base is formed with a plurality of conductorreceiving troughs. A leading end of a cord is inserted through an opening in the base which circumscribes substantially the periphery of the cord and which is adjacent the hinge and advanced to extend the leading end beyond the plug. The jacket is removed from a leading portion of the cord and the cord is retracted to fan out and position each conductor in a trough. Then, the cover is closed and bonded to the base to confine each conductor in a trough and to engage a portion of the jacket to provide strain relief therefor. Individual strain relief is also provided for each conductor. Flat blade-like terminals are inserted from an external face of the base into terminal-receiving grooves which are aligned with and which communicate with associated ones of the troughs. The terminals have tangs which extend into the troughs to make electrical contact with associated ones of the conductors.
BRIEF DESCRIPTION OF THE DRAWINGS Other features of the present invention will be more readily understood from the following detailed description of specified embodiments thereof when read in conjunction with accompanying drawings, in which:
FIG. 1 is a perspective view of a telephone set showing the inventive plugs inserted into a handset and a base portion thereof;
FIG. 2 is a perspective view of one of the plugs with a cord and terminals prior to assembly with the plug for purposes of clarity and further showing a hinged dielectric portion of the plug in an open position;
FIG. 3 is a perspective view of the plug shown in FIG. 2 with the conductors of the cord fanned out and received in associated ones of a plurality of conductorreceiving troughs;
FIGS. 4A4D are a sequence of views in elevation partially in section and showing the assembly of the plug with the cord and terminals in accordance with the principles of this invention;
FIG. 5 is a view showing the relationship between the plug illustrated in FIG. 2 being inserted into a handset portion of the telephone illustrated in FIG. 1;
FIG. 6 is a view similar to that of FIG. 5 but at a later time with the plug being seated and locked within the handset portion of the telephone; and
FIG. 7 is a perspective view of an apparatus which may be used to carry out the steps of the methods of this invention.
DETAILED DESCRIPTION OVERALL with a plug, designated generally by the numeral 14, at
the handset and thereof and at the base end thereof. The plug 14 has facilities for establishing an electrical connection between the cord 13 and internal contacting components 16-16 of the telephone (see FIG. 5).
Referring now to FIG. 2, a more detailed view of the structure of the retractile cord 13 can be seen. The retractile cord 13 includes a jacket 17 and a plurality of insulated conductors 18-18. The free end portion of each of the conductors 18-18 is designed to be connected to an associated one of a plurality of terminals 19-19.
Miniature plugs disclosed in the prior art may be advantageously used in many telephone environments where the insulated conductors 18-18 have the same spacing (0.037 inch) as the external components 16-16 with which the plug 14 makes contact. There are some telephone apparatus having external components which are spaced further apart (0.125 inch) than conductors 18l8 in the cord '13 to be connected thereto. This requires a fanning out of the conductors 18-18 in assembling the cord 13 to the plug 14 which is not feasible with some of the heretofore discussed prior art plugs. Plugs constructed in accordance with the present inventions permit the fannout out of the conductors 18l8 to be aligned with terminals which are aligned with external contact components.
DIELECTRIC PORTION The detailed construction of the plug 14 is shown in FIGS. 2, 3, and 4. A rigid, dielectric base, designated generally by the number, 30, is designed to be easily molded by using conventional injection-molding techniques. The rigid. dielectric base has a free end 31, a cord-input end 32 and a terminal-side 33 (see FIG. 4A).
7 It may be observed from FIGS. 3 and 4D that the base 30 is formed with a cord-input aperture 34 which circumscribes substantially the portion of the jacket 17 of the cord 13 extending therethrough. As can best be seen in FIG. 4A, the cord-input aperture 34 is formed entirely in the base 30 of the plug 14 and has a flared entrance to facilitate insertion of a leading end of the cord 13. The cord-input aperture 34 opens into a cavity 36 which terminates in a ledge 37 at the free end 31 of the base 30. This facilitates the automatic assembly of the plug 14 to the cord 13.
As has been noted, the formation of the cord-input aperture 34 entirely in the base 30 and sized to substantially circumscribe the cord 13 is advantageous during the assembly of the cord to the plug 14. This holds the cord 13 while other operations are performed by automated equipment. This is unlike prior art connectors having separate base and cover. In those, a portion of a conductor-access opening is formed in the base and a portion in a lid which is later bonded thereto. The cord 13 is generally positioned in the portion of the opening in the base and then the cover is applied. This will not suffice to hold the cord 13 in the base during assembly without additional steps and equipment.
A plurality of longitudinally extending partitions 38-38 are molded with the dielectric base 30 and extend into the cavity 36. A plurality of conductorreceiving troughs 39-39 (FIG. 2) are formed between the partitions 38-38 and open to the free end 31. The conductor-receiving troughs 3939 are designed to receive associated ones of the conductors 18l8. Each of the troughs 39-39 is dimensioned so that the conductor 18 therein cannot move laterally therein. This is necessary to insure that during the insertion of the terminals 19-19, the terminals remain aligned with the conductors 18-18 to make electrical engagement therewith.
It may be observed from FIG. 2 that the bottoms of the troughs 3939 are substantially coplanar with the top surface of the ledge 37. This facilitates the use of the ledge 37 for conductor cut-off during the assembly of the plug 14 to the cord 13.
The partitions 38-38 are discontinued somewhat short of the conductor access opening 34 and emerge into a sloping surface 41 formed adjacent the access opening. Attention is also directed to energy directors 42-42 formed longitudinally along the partitions 38-38. The energy directors 42-42 are dimensioned to provide for adequate bonding of a cover 46 to the base 30 of the plug 14 in accordance with the specifications provided by manufacturers of commercial ultrasonic equipment. For example, see D. J. Kolb Designing Plastic Parts for Ultrasonic Assembly in the Mar. 16, 1967 issue of Machine Design.
The cover 46 is molded integrally with the dielectric base 30 and is mounted pivotally along a plastic hinge 47 (see FIGS. 2, 3, and 4). The plastic hinge 47 extends transversely along the dielectric base 30.
The use of the hinged cover 46 offers certain advantages. Since it is pre-attached to the base 30, alignment problems on closure are circumvented. Also, by molding the cover integrally with the base 30 in a open position, the step of hingeing a separate part to the base is saved. Moreover, molding the cover in an open position presents the plug in a ready-for-assembly condition with no additional preparation necessary.
As can also be seen in FIG. 2, the cover 46 has a plurality of spaced parallel ribs 48-48 projecting therefrom toward the base 30. The ribs 48-48 are positioned to be intermediate the partitions 38-38. Also, the ribs 48-48 extend from the cover 46 a sufficient distance so that when the cover is closed and bonded to the base 30, the ribs will engage and confine the associated ones of the conductors 18-18. In this way, when the cover 46 is closed, the ribs 48-48 engage the conductors 18-18 received in the troughs 39-39 to secure the conductors within the troughs.
The ability to be able to precisely confine the conductors 18-18 is especially important. Prohibition against movement is necessary in order to cause the terminals 19-19 to penetrate the nylon-insulated conductors 18-18. The terminals 19-19 must be inserted with sufficiently high forces imparted thereto to penetrate the insulation. If the conductors 18-18 were free to move laterally, the terminals 19-19 may very well slice into the insulation on either side of the conductive elements and fail to establish engagement therewith.
The plug 14 also has provisions to alleviate strain relief on the cord jacket 17 during customer use. The cover 46 has a cord anchoring lug 49 (see FIG. 4A) projecting from the underside thereof. As can be seen in FIG. 4D, the cord anchoring lug 49 is spaced along the underside of the cover 46 so that when the cover is closed, the anchoring lug is aligned with a well 51 formed in the base 30. The well 51 communicates the exterior of the plug 14 with the cavity 36. When the cover 46 is closed (see FIG. 4D) with the cord 13 being inserted into the plug 14, the anchoring lug 49 engages the jacket 17 and urges a portion of the cord 13 into the well 51. The cord 13 assumes a tortuous configuration around the anchoring lug 49.
Strain relief is also provided for the individual conductors 18-18. As is shown in FIG. 2, a plurality of conductor anchoring teeth 5252 are formed on the underside of the cover 46 intermediate the hinge 47 and the free end thereof. The teeth 5252 are aligned with the conductor-receiving troughs 39-39. When the cover 46 is closed on the base with the conductors 18-18 received within the troughs 39-39, the teeth 5252 engage associated ones of the conductors (see FIG. 4D) and deform the insulation thereof to secure the conductors within the plug 14.
In this way, the terminals 19-19 function only to make electrical contact with the conductors 18-18 and are not required to retain the conductors and resist the forces imparted to the conductors during customer use. These forces occur notwithstanding the anchoring of the cord 13. This is due to the jacket having a much greater elongation than the core of the cord 13. If strain relief were not provided for the conductors 18-18, desirably on an individual basis, pull-out of one or more of the conductors may occur during use of the telephone.
As can best be seen in FIG. 4A, the plug 14 is formed with a plurality of spaced parallel terminal-receiving openings in the form of grooves 56-56 which are aligned on a one-to-one basis with associated ones of the conductor-receiving troughs 39-39. Each of the terminal-receiving grooves 56-56 is of a length substantially equal the overall length of a terminal 19. Each of the terminal-receiving grooves 56-56 communicates with the associated conductor-receiving trough 39 through a slot 57. The slot 57 is shorter than the associated terminal-receiving groove 56 and is of a length slightly less than the out-to-out distance of that portion of a terminal 19 which is to be received therein. The shortening of the slots 57-57 from the terminalreceiving grooves 56-56 forms abutments 58-58 (see FIG. 4A for example).
Formed integrally with the dielectric portion 30 is a resilient locking tab 61. The locking tab 61 is approximately 0.035 inch thick, 0.300 inch wide, 0.500 inch long, and is molded so that its longitudinal axis is oriented at an angle of approximately 15 with respect to the plane of the terminal-inserting side 33. A hinge end 62 of the locking tab 61 is molded into one side of a bridge projection 63, substantially in the middle of the projection.
The combined height of the bridge projection 63, thickness of the locking tab 61 and resilience of the locking tab permits insertion of the plug 14 into the handset 12 between opposing surfaces 64 and 66 (see FIG. 5). The tab 61 can be deflected inwardly of the dielectric base 30 to become substantially coplanar with the outermost surface of the bridge projection (see FIG. 5) and be moved slidably in engagement with the surface 64.
After being released, the locking tab 61 will resume its originally molded shape and orientation because of its natural resilience. Proper resilience to provide the desired flexing properties can be incorporated into the locking tab 61 when it is molded from polycarbonate with the aforementioned dimensions. The return of the tab 61 to its originally molded shape causes the free end of the tab to be urged downwardly into seating engagement with a ledge 67 (see FIG. 6) formed in the handset 12 and the base 11. This locks the plug 14 to the handset 12 and insures integrity of the connection during customer use.
TERMINALS As can best be seen in FIG. 2, each one of the terminals 19-19 is made from a generally flat strip of electrically conductive resilient material such as Phosphor bronze. Moreover, each one of the terminals 19-19 includes at least one contact or insulation-piercing tang 71 which provides electrical connection between the conductive portion of the conductor 18 and the associated one of the terminals 19-19.
Each of the blade-like terminals 19-19 also has a flat contact portion 72 which is utilized to complete the connection between the associated conductor 18 and an associated internal-contacting component 16 illustrated in FIG. 5, and positioned in the telephone 10.
Provisions are also made for seating properly the terminals 19-19 within the associated terminal-receiving grooves 56-56. Each of the terminals 19-19 is formed with positioning shoulders 74-74. These shoulders 74-74 engage with the end faces of the grooves 56-56 to locate the terminals 19-19 properly longitudinally within the grooves. The shoulders 74-74 also engage with the abutments 58-58 to seat the terminals 19-19 within the grooves properly with respect to depth. This insures that the terminals 19-19 are seated at a distance spaced from the conductor such that the tangs 71-71 engage with the conductive portion of the conductor. If spaced excessively, the tangs 71-71 may not extend to the conductive portions; and if spaced too closely, there may be a deforming of the tangs or of the conductor.
There are also provisions for retaining the terminals 19-19 within the terminal-receiving grooves 56-56. Each of the terminals 19-19 is formed with barbs 76-76 which extend from end ones of the tangs 71-71. These penetrate the material of the plug which define the terminal-receiving grooves 56-56 when the terminals are assembled therewith. The barbs 76-76 dig into the end walls of each of the slots 57-57 to securely anchor the terminal within the plug 14.
METHOD OF ASSEMBLING PLUG WITH CORD The construction of the plug 14 is especially adapted to be used with flat cordage. Moreover, the plug 14 is easily adapted to automated high speed manufacturing. In describing the assembly of the plug 14 and the cord 13, reference will be made to FIGS. 4A-4D which depict the steps of the method. Reference will also be made to FIG. 7 which illustrates an apparatus, designated generally by the numeral 80, which is exemplary of apparatus which may be used to carry out the steps of the method.
One of the plugs 14-14 with the cover 46 thereof in the open position is positioned in a workholder 81 (see FIG. 7). Then a leading end of the jacketed cord 13 is inserted between a grooved roller 82 and a drive roller 83. The groove in the roller 82 is constructed so that when the cord 13 is positioned therein, portions of the cord extend above the periphery of the roller. The drive roller 83 is mounted adjacent the grooved roller 82 so as to engage the portions of the cord 13 exposed above the groove. The drive roller 83 is turned to advance the leading end of the cord 13 through the plug 14 until it extends well beyond the free end 31 of the plug (see FIG. 4B).
A plate 84 and a spring-biased rod 86 are positioned between the base 30 and the cover 46 prior to the advancement of the leading end of the cord 13 through the plug 14. The cord 31 is advanced between the plate 84 and the tops of the partitions 38-38. Since the outside diameter of the cord 13 is significantly greater than the width of each of the troughs 39-39, successive sections of the cord are maintained in engagement with the top surfaces of the partitions 38-38. The plate 84 is of assistance in maintaining the path of the leading end of the cord 13 in a predetermined direction to facilitate further processing.
It is advantageous to construct the base 30 with the cord-input aperture 34 which circumscribes substantially the cord 13. This provides total lateral support for the cord 13 intermediate the convolutions and the free end thereof during its assembly with the plug 14. This is unlike prior art devices wherein only the base may include a U-shaped opening. in assembling those devices, the cord 13 must be held within the opening during the arrangement of the conductors 18-18 within the base and the assembly of a lid thereto.
in the next step of the inventive method, a stripping device 87 is controlled to remove a length of the jacket 17 from the cord 13. This exposes individual ones of the conductors 18-18 which have their own primary insulative covering. The stripping device 87 is then returned to an initial position.
Then the rotation of the drive roller 82 is reversed to withdraw the leading end portion of the cord toward and at least partially within the plug (see FIG. 4C). The cord 13 is retracted until the exposed individual conductors 18-18 extend to a point which will be intermediate the anchoring lug 49 and the anchoring teeth 52-52 (see FIG. 4D) when the cover is closed.
A combing head 91 is moved along a path spaced above and aligned with that of the cord. Simultaneously with the retraction of the cord 13, the conductors 18-18 are fanned out and received separately in associated ones of the conductor-receiving troughs. The fanning out of the conductors 18-18 simultaneous with the retraction of the cord 13 is accomplished by controlling a plurality of selectively movable camming blades 88 and 89 (see FIG. 7) which are mounted in the head 91.
To describe the fanning out operation, it is assumed that the cord 13 includes five conductors 18-18, a center conductor, two intermediate conductors and two outside conductors. As the cord 13 is retracted, the
.blades 88-88 are moved downwardly between the center and immediate conductors. Then the blades 88-88 are turned rotatably within the head 91 to space apart the center and intermediate conductors. Simultaneously therewith, the blades 89-89 are moved downwardly between the intermediate and outer conductor 18-18 and turned. This causes the conductors 18-18 to be spaced apart and permit the plate 84 to cause the conductors to be moved into the troughs 39-39.
This is accomplished by controlling the rod 86 to urge the plate 84 into engagement with the top surfaces of the partitions 38-38. This causes the jacketed portions of the cord 13 extending from the cord input aperture 37 to be urged into engagement with the sloping surface 41. Also, the individual conductors 18-18 are moved into associated ones of the troughs 39-39 and maintained therein by the plate 84.
Because the cord 13 is flat and because of the assembly process, the conductors 18-18 are spaced in a prearranged order in the troughs 39-39. It is unnecessary for an operator to identify the conductors 18-18 prior to the electrical connection with ones of the terminals 19-19. The order in the cord 13 is maintained in the plug 30 to correspond to the order of engagement with the external contacting components 16-16.
In a next step of the method which embodies the principles of this invention, an ultrasonic bonding tool 92 is moved downwardly into engagement with the dielectric cover 46. The bonding tool 92 is moved further downwardly to apply forces to the cover 46 to move pivotally the cover about the hinge 47 and to engage the cover with the base 30 (see FIG. 4D). Simultaneously, therod 86 is moved toward the free end 31 of the base while maintaining pressure against the plate 84. This maintains the plate 84 in engagement with the top surfaces of the partitions 38-38 to maintain the conductors 18-18 within the troughs 39-39 while the cover 46 is being closed.
As this is done, the anchoring lug 49 engages the jacketed portion of the cord 13 while the anchoring teeth 52-52 engage the individual conductors 18-18. This arrangement provides strain relief for both the cord 13 and for the individual conductors 18-18. With these provisions for strain relief, the maintenance of electrical continuity is greatly enhanced. Notwithstanding the very great difference in elongation characteristics between the jacket material and the individual conductors, the individual clamping of each conductor 18 will maintain the conductors in the troughs when subjected to forces imparted thereto during customer use.
As the cover 46 is moved pivotally to a closed position, the plate 84 is withdrawn slidably toward the free end 31 of the plug 14. During withdrawal, the plate 84 is maintained in engagement with portions of the top surfaces of the partitions 38-38. After the plate 84 and rod 86 are withdrawn completely and the cover 46 closed, the ultrasonic bonding tool 92 is controlled to bond the cover to the base 30.
The advantages of the cover 46 being integrally hinged with the base 30 should be apparent. Additional assembly steps and apparatus therefor are unnecessary. Also, tedious alignment problems of miniature bases and separate covers prior to bonding are overcome.
Moreover, the construction of the plug with the cordinput aperture 34 totally within the base 30 and with the cover 46 hinged to the base 30, facilitates the fanning out of the conductors 18-18. Since the cord 13 is held laterally at the cord-input aperture 34, additional holding facilities areunnecessary and only the facilities for fanning out the conductors 18-18 are required.
It should also be noted that as the cover 46 is closed on the base 30 and bonded ultrasonically thereto, the ribs 48 are received between associated conductors 18-18 to complete the lateral confinement thereof in the associated throughs 39-39.
The free end portions of the conductors 18-18 are trimmed off with a cutting device 93 and using the ledge 37 as a bearing surface. The extension onto the ledge 37 and the cut off is necessary to compensate for the snubbing action of the closing of the cover 46 on the conductors. Had the conductors 18-18 been retracted to precisely align the ends thereof with the ends of the troughs, then when the cover is closed, the snubbing action would cause the conductors to move longitudinally within the troughs. Also, the paths of the conductors l8l8 within the plug 14 vary. Presizing the conductors 18-18 would result in outside ones of the conductors being withdrawn in the troughs 39-39. This could possibly result in the loss of electrical contact of the outer ones of the terminals 19-19 with the outer conductors, i.e., those conductors adjacent the sides of the base 30.
The above-described arrangement is easily adaptable to an automation process. The flat cord 13 has the conductors 18-18 in an ordered predetermined sequence which are to be received in the same order in the troughs 39-39. The retraction of the length of the cord 13 back into the dielectric portion 30 maintains the conductors in the same order and no further identification is required.
in order to complete the assembly of the plug 14 to an end of the cord 13, five of the terminals 19-19 are inserted into the plug. The blade-like terminals 19-19 are inserted from the terminal-receiving face 33 of the plug 14 into associated ones of the terminal-receiving grooves 56-56 until the positioning shoulders 74-74 seat into engagement with the abutments 58-58 (see FIG. 4D). At that time, the contact tangs 71-71 extend through the aligned slots 57-57 and into the associated troughs 39-39. The tangs 71-71 penetrate the insulation of the conductors 18-18 confined in the troughs 39-39 and establish electrical contact with the conducitve elements thereof.
Also, the barbs 76-76 are caused to become embedded in the portion of the dielectric base 30 which defines the slots 57-57. This anchors the terminals- 71-71 against movement or inadvertent removal from the base 30.
In use, the lower edge portion of each of the bladelike terminals 19-19 engages electrically with an associated external contacting portion 16 (see FIG. 5).
Of course, apparatus other than the apparatus 80 may be used to practice the methods of this invention. For example, the assembly of the plug 14 to the cord 13 could be accomplished by using'a turntabletnot shown) with facilities for inserting the cord, stripping the cord etc. arranged about the periphery of the turntable. Successive cords 13-13 and associated plugs 14-14 are moved with the turntable (not shown) through the work stations.
It is to be understood that the above-described arrangements are simply illustrative of the invention. Other arrangements may be devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.
What is claimed is: 1. An electrical connector for terminating a cord including a plurality of insulated conductors and for making electrical contact external to the connector, which comprises:
a base, which includes a cord-input end having an aperture for receiving and substantially circumscribing the cord, the base also including a portion having conductor-receiving troughs and a plurality of terminal-receiving openings extending generally parallel to and communicating with the troughs and the exterior of the connector, the inverts of the troughs to which the terminal-receiving openings communicate being in substantially the same plane as a portion of the wall of the cord-input opening, the base being formed with a well between the cord-input end and the conductor-receiving troughs for receiving the portion of the jacketed cord, the base being formed with a ramp extending from the well to the troughs to facilitate the advance of a leading end of a cord from the cord input end beyond the troughs; a plurality of electrically conductive blade-like terminals positioned within the base each of which includes: an internal contact portion extending into the trough for piercing the insulation of and making electrical engagement with the conductor in the trough; and
an external contact portion positioned within the associated terminal-receiving opening for making electrical contact external to the connector; and
a cover having one end formed integrally with the base along a web portion which is substantially less in thickness than the cover or the walls of the base defining the cord-input aperture, the web portion being adjacent the cord-input end and moveable with respect thereto to cause a portion thereof to engage the portion of the base having the conductor-receiving troughs to confine the conductors and to prevent lateral movement thereof to insure that the positioning of the terminals within the openings cause the internal contact portions of the terminals to engage electrically the associated insulated conductors, the cover also being formed with an anchoring lug extending from the underside thereof and which engages the jacketed portion of the cord after the cord has been inserted into the cord-receiving opening and the cover closed, the portion of the cord engaged by the anchoring lug being formed along a tortuous path around the anchoring lug and extending into the well to provide strain relief for the cord during use thereof.
2. The electrical connector of claim 1, wherein the cover is formed with a plurality of conductor-engaging teeth on the underside thereof and extending toward the base, each of the teeth being aligned with an associated conductor-receiving trough. so that when the cover is closed on the base, each of the teeth engages the insulation of the conductor positioned in the associated conductor-receiving trough to provide strain relief for the individual conductors during use.
3. The electrical connector of claim 1, wherein the free end of the base extends beyond the cover when the cover is in a closed position to provide a bearing surface for cutting off exposed end portions of the conductors which extend beyond the free end of the cover.
4. The connector of claim 1, wherein the terminalreceiving openings include a plurality of spaced grooves opening to an external surface of the connector and associated slots communicating the grooves with associated ones of the troughs, each of the slots being of a size to permit the internal contact portion of a terminal to pass therethrough.
5. The connector of claim 4, wherein the internal contact portions of each terminal includes a plurality of contact tangs which extend through the slots and into electrical engagement with the conductor in the associated trough.
6. The connector of claim 5, wherein each of the terminals is formed with barbs extending from portions of the tangs which are positioned within the slots and an overall longitudinal dimension thereof is slightly greater than the longitudinal dimension of the slot which communicates the associated groove and trough to facilitate the end barbs of the terminal becoming embeded in the walls of the slot when the terminals are inserted to anchor the terminals within the base.
7. The connector of claim 4, wherein each of the grooves of each terminal-receiving opening is formed to extend beyond the ends of each associated slot to form an abutment at each end of the groove.
8. The connector of claim 7, wherein each of the terminals includes a shoulder at each end thereof for engaging the abutments of the associated terminalreceiving groove to seat the terminal properly within the opening.
9. The connector of claim 1, wherein the cord-input aperture has an inner portion approximately the same cross-section of the cord with the walls of the aperture diverging continuously from the inner portion to the cord-input end of the connector and forming a flared inlet to facilitate insertion of the leading end of the cord.
10. A method of assembling a device to a cord for connecting electrically individual conductors which comprise the cord to associated components external to the device, the device including a base having a cord-input aperture which circumscribes and is in engagement substantially with the periphery of a section of the cord extending therethrough, the base further having conductor-receiving troughs and terminalreceiving openings communicating with associated troughs and a cover hinged integrally to the base adjacent the cord-input aperture and adapted to mate with the base, which includes the steps of:
holding the base with the cover hinged open therefrom;
inserting the leading portion of the cord into the cord-input aperture;
causing relative motion between the device and the cord to advance the leading portion of the cord beyond the base;
exposing the individual insulated conductors of a predetermined length of the leading portion of the cord by removing the jacket therefrom;
retracting at least a section of the leading portion of the cord within the base; while positioning the individual ones of the conductors within associated ones of the troughs;
causing the cover to be closed on and secured to the base to confine the conductors within the associated troughs and prevent unintended lateral and longitudinal movement thereof; and
inserting and seating terminals in the terminalreceiving openings such that internal contact portions thereof extend into the troughs and pierce the insulation of the associated conductors to establish an electrical connection with the conductors and to expose external contact portions thereof for engagement with the external components.
11. The method of claim 10, wherein the cord is inserted into the device with the conductors arranged in a specific orientation such that when jacket is removed from leading portion of the cord, the. orientation of the conductors corresponds to that of the associated conductor-receiving troughs thereby obviating identification of the individual conductors before placement thereof in the associated troughs.
12. The method of claim 10, wherein the spacing of the troughs corresponding to the spacing of the external components is greater than that of the conductors within the jacketed cord and positioning of the conductors in the troughs includes fanning out the conductors while the cord is being retracted to align the conductors with the associated troughs.
13. The method of claim 10, wherein the cord is retracted so that leading portions of the individual conductors extend beyond a free end of the device opposite that end having the cord-input aperture and the method includes the further step of severing those portions of the conductors extending beyond the device subsequent to the closing of the cover.