Terminal positioning system

Information

  • Patent Grant
  • 6176748
  • Patent Number
    6,176,748
  • Date Filed
    Tuesday, November 24, 1998
    26 years ago
  • Date Issued
    Tuesday, January 23, 2001
    24 years ago
Abstract
An electrical connector includes a housing molded of dielectric material and having a recess defined by opposed side walls having inner surfaces. A plurality of terminals are mounted on the housing and include contact sections along at least one of the opposed side walls and exposed at the inner surface thereof. The terminals have distal ends at an end of the recess. At least some of the terminals have spacer tabs projecting laterally from edges of the contact sections of the terminals to maintain at least a minimum spacing between the distal ends of the terminals prior to molding the dielectric housing.
Description




FIELD OF THE INVENTION




This invention generally relates to the art of electrical connectors and, particularly, to a system to facilitate positioning terminals in an overmolded housing.




BACKGROUND OF THE INVENTION




Generally, a typical electrical connector includes an insulating or dielectric housing defining some form of mating configuration for mating the connector with a complementary mating connector or other connecting device. For example, the connector housing may define a male or plug connector, or the connector housing may define a female or socket connector. The dielectric housing may be a stand-alone component, or it may be adapted for mounting on a printed circuit board, in a panel or in association with other mounting structures.




One or more conductive terminals are mounted on or in the connector housing. The terminals can have a wide range of configurations depending on the use of the connector. However, the terminals typically have contact portions for engaging the contact portions of terminals in the complementary mating connecting device. One type of terminal is a stamped and formed terminal of sheet metal material, and such terminals may have a contact leg or blade of flat sheet metal material.




Some form of retention system must be employed to hold the terminals on or in the connector housing. The retention systems also vary widely. The terminals may be press-fit into terminal-receiving cavities, or the terminals may have latching portions for latching with complementary latches on the connector housing. One form of retention system involves overmolding a plastic housing about portions of the terminals to rigidify and hold the terminals on the housing.




One problem with overmolding terminals as described above concerns maintaining portions of the terminals, such as the contact portions, at proper positioning, spacing or pitch during the overmolding process. This is particularly problematic with the ever-increasing miniaturization of electrical connectors, whereby the terminals are very small and the contact portions of the terminals are extremely narrow and closely spaced. For instance, if the contact portions or other portions of the terminals are so closely spaced as to be touching each other, corresponding portions of the molding die may not even be able to be positioned between the terminal portions. The terminal portions actually can be damaged when the mold tooling is closed. In addition, when the molten dielectric (plastic) material is inserted into the mold, the material is under high pressure and can actually move or bend the terminal portions. The present invention is directed to solving these problems in such electrical connectors which include dielectric housings overmolded about metal terminals.




SUMMARY OF THE INVENTION




An object, therefore, of the invention is to provide an electrical connector with a new and improved system to facilitate positioning terminals during an overmolding process.




In the exemplary embodiment of the invention, an electrical connector includes a housing molded of dielectric material and having a recess defined by opposed side walls having inner surfaces. A plurality of terminals are mounted on the housing and include contact sections along at least one of the opposed side walls and exposed at the inner surface thereof. The terminals have distal ends at an end of the recess. At least some of the terminals have a spacer tab projecting laterally from an edge of the contact section of the terminal to maintain at least a minimum spacing between the distal ends of the terminals prior to molding the dielectric housing.




As disclosed herein, the terminals are at least partially insert-molded in the housing. Preferably, each terminal has one of the spacer tabs projecting from each opposite edge of the contact section of the terminal. The distal ends of the terminals are bent at an angle to the contact sections of the terminals outwardly of the recess at the end thereof.




In one embodiment of the invention, the distal ends of the terminals are angled to define a tapered head to engage a correspondingly tapered recess in a wall of a mold cavity. In another embodiment of the invention, the distal ends of the terminals are curved to define a curved head to engage a correspondingly curved recess in a wall of a mold cavity. Preferably, the curved distal ends of the terminals are parabolic.




Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWINGS




The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which:





FIG. 1

is a top perspective view of an electrical connector embodying the concepts of the invention;





FIG. 2

is a bottom perspective view of the connector;





FIG. 3

is a top plan view of the connector;





FIG. 4

is a bottom plan view of the connector;





FIG. 5

is a side elevational view of the connector;





FIG. 6

is an end elevational view of the connector;





FIG. 7

is an enlarged, fragmented bottom perspective view of one end of the connector;





FIG. 8

is a fragmented and enlarged view of retention sections of terminals according to one embodiment of the invention juxtaposed with an inner wall of the mold cavity;





FIG. 9

is a fragmented and enlarged perspective view of the distal ends of terminals according to a second embodiment of the invention juxtaposed with an outer wall of a mold cavity;





FIG. 10

is a view similar to that of

FIG. 9

, but with the distal ends of the terminals according to a third embodiment disposed in a mold cavity.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring to the drawings in greater detail, and first to FIGS.


1


-


6


, the invention is embodied in an electrical connector, generally designated


10


, which is designed for mounting on a circuit board. The connector includes a one-piece dielectric housing, generally designated


12


, molded of plastic material or the like. The housing defines a mating end


14


and a mounting end or face


16


. The housing is elongated and includes a metal securing member or “fitting nail”


18


at each longitudinal end thereof for fixing, as by soldering, to a pair of spaced securing pads on the circuit board. Mating end


14


of the housing has opposed side walls


20


including upper portions


21


that define a mating recess, generally designated


24


, and a bottom wall


25


. The upper portions


21


of opposed side walls have upper, inner surfaces


26


.




The housing also defines an elongated mounting recess, generally designated


28


, which is bounded by lower portions


30


of opposed side walls


20


. The mating recess


24


and mounting recess


28


are separated by a bottom wall


25


. Finally, a plurality of stiffening ribs


34


(

FIG. 4

) are molded integrally with and interconnect lower portions


30


of opposed side walls


20


and span mounting recess


28


.




A plurality of terminals, generally designated


36


, are insert-molded in housing


12


partially in upper portions


21


and lower portions


30


of opposed side walls


20


of mating recess


24


and mounting recess


28


, respectively. Each terminal is stamped and formed of conductive sheet metal material and includes a contact section


38


having a distal end


40


bent outwardly at an angle to the contact section, and a retention section


42


having a solder tail


44


bent outwardly at an angle to the retention section. As best seen in

FIGS. 1 and 3

, contact sections


38


of the terminals have inside faces generally flush with inner surfaces


26


of opposed side walls


20


.





FIGS. 2 and 7

best show a system for retaining sections of the terminals in the side walls of the housing. It should be understood that the system is disclosed herein for retaining retention sections


42


of the terminals. However, the system can be used for retaining other sections of the terminals, such as retaining contact sections


38


in side walls


20


within mating recess


24


.




With that understanding, and referring to

FIGS. 2 and 7

, a plurality of ribs


46


are molded integrally with housing


12


to project inwardly of opposed side walls


20


between retention sections


42


of adjacent terminals


36


. Side edges


48


of the ribs are molded to overlap and tightly capture side edges


50


of the terminal retention sections. Therefore, the ribs will resist any inward movement of the retention sections in the direction of arrow “A” (FIG.


7


).




Preferably, ribs


46


are trapezoidal in cross-section as clearly seen in FIG.


7


. The ribs are oriented such that the side edges of the ribs which overlap the side edges of the terminal retention sections are at the corners of the widest sides


46


a of the ribs. The narrowest sides


46


b of the ribs face inwardly into recess


28


.





FIG. 8

shows terminals


36


on a carrier


37


being positioned against an inner wall


80


of a mold cavity before molten plastic is injected around the terminals. The two left terminals


36


in

FIG. 8

are truncated for illustrative purposes. The inner wall


80


of the mold cavity has an array of projecting terminal supports


82


defining valleys


84


between adjacent terminal supports. When the molten plastic is injected into the mold cavity, plastic filling the valley


84


forms ribs


46


. The projections


82


engage terminal retention sections


42


. The terminal supports


82


are tapered inwardly to create diverging mouths


49


between adjacent ribs


46


to facilitate withdrawing the terminal supports inwardly from the terminals


36


after the ribs are overmolded over the edges of the terminals.





FIG. 9

shows terminals


36


on the carrier


37


being positioned against on outer wall


62


of a mold cavity before molten plastic is injected around the terminals. To precisely space the terminals in the housing of the connector, distal ends


40


of the terminals


36


are inserted into recesses


60


in outer wall


62


of the mold cavity.

FIG. 9

shows that the corners of distal ends


40


of the terminals are angled, as at


54


, to define a tapered head


55


. The recesses


60


are correspondingly tapered to accurately position each terminal


36


with respect to the mold and, consequently, the housing


12


. Angled corners


54


of adjacent terminals


36


provide a tapered mouth between the distal ends of each pair of adjacent terminals. The tapered mouth is in line with arrow “B” which defines the insertion direction of the partition


64


between adjacent recesses


60


in the wall


62


of the mold cavity.





FIG. 9

shows that each contact section


38


of each terminal


36


has spacer tabs


52


projecting laterally from opposite edges


38




a


of the contact sections. These spacer tabs maintain at least a minimum spacing between the contact sections and, particularly, between distal ends


40


of the terminals. This allows for the partition


64


of the wall


62


of the mold to enter between the distal ends


40


of the terminals in the direction of arrow “B” when the heads


55


are inserted into recesses


60


. Preferably, the spacer tabs


52


are as thick as the contact section


38


of the terminal


36


to insure that edges of adjacent tabs


52


abut instead of overlap.





FIG. 10

shows an alternate embodiment wherein the sides of distal ends


40


of terminals


36


are curved, as at


56


to define curved heads


58


. The recesses


66


are correspondingly carved to receive curved heads


58


. The correspondingly curved heads


58


and recesses


66


include fewer jagged surfaces thereby facilitating smooth insertion of the heads


58


into recesses


66


. The curved sides of the distal ends


40


define a rounded mouth between adjacent terminals for receiving the partition


70


between recesses


66


of the mold wall


68


in the direction of arrow “B” when heads


58


are inserted into recesses


66


. Preferably, the curvature of rounded sides or edges


56


of distal ends


40


is parabolic to define parabolic profiles for the sides of the mouth which receives the partition


70


between recesses


66


of mold wall


68


when heads


58


are inserted into recesses


66


.




It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.



Claims
  • 1. An electrical connector, comprising:a housing molded of dielectric material and having a recess defined by opposed side walls having inner surfaces; and a plurality of terminals mounted on the housing and including contact sections along at least one of the opposed side walls and exposed at the inner surface thereof, the terminals having distal ends at an end of the recess, and at least some of the terminals having a spacer tab projecting laterally from an edge of the contact section of the terminal to maintain at least a minimum spacing between the distal ends of the terminals prior to molding the dielectric housing; said spacer tab being generally coplanar with said contact section and substantially as thick as said contact section.
  • 2. The electrical connector of claim 1 wherein each terminal has one of said spacer tabs projecting from each opposite edge of the contact section of the terminal.
  • 3. The electrical connector of claim 1 wherein said dielectric housing is of molded plastic material, and the terminals are at least partially insert molded in the housing.
  • 4. The electrical connector of claim 1 wherein said distal ends of the terminals are angled to define a tapered head.
  • 5. The electrical connector of claim 1 wherein said distal ends of the terminals are curved to define a curved head.
  • 6. The electrical connector of claim 5 wherein said curved distal ends of the terminals are parabolic.
  • 7. The electrical connector of claim 1 wherein said distal ends of the terminals are bent at an angle to the contact sections of the terminals outwardly of the recess at the end thereof.
  • 8. The electrical connector of claim 7 wherein said distal ends of the terminals are angled to define a tapered head.
  • 9. The electrical connector of claim 7 wherein said distal ends of the terminals are curved to define a curved head.
  • 10. The electrical connector of claim 9 wherein said curved distal ends of the terminals are parabolic.
  • 11. An electrical connector, comprising:a dielectric housing having an open ended recess defining a mating end of the housing for receiving complementary mating connector device, the recess being defined by opposed side walls having inner surfaces; and a plurality of terminals mounted on the housing and including contact sections spaced along said opposed side walls and exposed at the inner surface thereof, the terminals having distal ends bent at angles to the contact sections outwardly of the recess thereof, and each terminal having a spacer tab projecting outwardly from each opposite edge of the contact section of the terminal to maintain at least a minimum spacing between the distal ends of the terminals prior to molding the dielectric housing; said spacer tab being generally coplanar with said contact section and substantially as thick as said contact section.
  • 12. The electrical connector of claim 11 wherein said dielectric housing is of molded plastic material, and the terminals are at least partially insert molded in the housing.
  • 13. The electrical connector of claim 11 wherein said distal ends of the terminals are angled to define a tapered head.
  • 14. The electrical connector of claim 11 wherein said distal ends of the terminals are curved to define a curved head.
  • 15. The electrical connector of claim 14 wherein said curved distal ends of the terminals are parabolic.
US Referenced Citations (10)
Number Name Date Kind
4330935 Blair, Jr. et al. May 1982
4418475 Ammon et al. Dec 1983
4429459 Lynch Feb 1984
4996766 Piorunneck et al. Mar 1991
5201883 Atoh et al. Apr 1993
5310357 Olson May 1994
5359761 Whitson et al. Nov 1994
5535513 Frantz Jul 1996
5718047 Nakayama et al. Feb 1998
5772474 Yagi et al. Jun 1998
Foreign Referenced Citations (3)
Number Date Country
1108257 Sep 1981 CA
693802 Jan 1996 DE
0092667 Jun 1986 EP