US3918784A

US3918784A - Miniature connector for circuit component

Info

Publication number: US3918784A
Application number: US476494A
Authority: US
Inventors: Timothy Allen Lemke; Jay Forrest Vogel
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1974-06-05
Filing date: 1974-06-05
Publication date: 1975-11-11
Anticipated expiration: 1992-11-11

Abstract

The invention relates to a miniature connector having a dielectric housing which is flexible for conforming to irregularities in the printed circuit board. A plurality of contacts are mounted in the housing. Each of the contacts includes a leaf spring portion in the form of a cantilever beam integral with the base portion and latched to the housing. The housing includes an opening at one end allowing for receipt of projecting posts mounted to a printed circuit board. When the housing is mounted on the surface of the printed circuit board the posts are electrically attached to the base portions of the contacts. The housing includes additional openings for pluggable receipt of male electrical terminals wedgingly engaged between the posts and leaf springs which cooperate to engage and grip the terminals.

Description

Lemke et al.

[451 Nov. 11, 1975 MINIATURE CONNECTOR FOR CIRCUIT COMPONENT [75] Inventors: Timothy Allen Lemke, Dillsburg;

Jay Forrest Vogel, Boiling Springs,

both of Pa. [73] Assignee: AMP Incorporated, Harrisburg, Pa. [22] Filed: June 5, 1974 211 App]. No.: 476,494

[52] U.S. Cl 339/17 C; 339/170 CF; 339/75 M; 339/95 D; 339/176 MP [51] .Int. Cl. HOIR 13/10 [58] Field of Search 339/17 C, 17 CF, 17 L, 339/176 MP, 174, 61 M, 75 M. 17 LC, 17

LM, 95 D [56] References Cited UNITED STATES PATENTS 3,673,543 6/1972 Garner 339/17 CF X Primary E.\'mniner-Roy Lake Assistant Examiner-E. F. Desmond Attorney, Agent. or Firm-Gerald K Kita 57 ABSTRACT The invention relates to a miniature connector having a dielectric housing which is flexible for conforming to irregularities in the printed circuit board. A plurality of contacts are mounted in the housing. Each of the contacts includes a leaf spring portion in the form of a cantilever beam integral with the base portion and latched to the housing. The housing includes an opening at one end allowing for receipt of projecting posts mounted to a printed circuit board. When the housing is mounted on the surface of the printed circuit board the posts are electrically attached to the base portions of the contacts. The housing includes additional openings for pluggable receipt of male electrical terminals wedgingly engaged between the posts and leaf springs which cooperate to engage and grip the terminals.

9 Claims, 6 Drawing Figures US. Patent Nov. 11, 1975 Sheet 1 of3 US. Patent Nov. 11, 1975 Sheet30f3 3,918,784

MINIATURE CONNECTOR FOR CIRCUIT COMPONENT BACKGROUND OF THE PRIOR ART In the prior art it has been the practice to provide a printed circuit board with posts or pins projecting from one side allowing for lengths of wires to form circuit interconnections among the pins. On the other surface of the printed circuit board it has been the practice to mount electronic circuit components usually in the form of solid state elements provided with two rows of depending electrical leads and encapsulated to form a dual-in-line package. The depending leads provide male electrical terminals which require pluggable connection to the printed circuit board. Such connections were usually accomplished by plugging the terminals into headers which comprise resilient electrical sockets or receptacles contained within a dielectric housing. It has been a problem to electrically connect the sockets of such headers to the circuitry of the printed circuit board. Another problem exists in designing an operating socket of miniature size and in preventing damage to the sockets upon repeated or forcible insertion of the leads.

BRIEF DESCRIPTION OF THE PRESENT INVENTION The present invention provides a connector design wherein a dielectric housing of the connector is flexible for readily conforming to the surface of a printed circuit board. The electrical receptacle design of the present invention eliminates the complexity of prior art sockets enabling greater ease in manufacture and greater strength and resistance to damage than the sockets of the prior art. In addition each receptacle of the present invention is formed by an inexpensive metal leaf spring which cooperates with the noble metal terminal post or pin commonly associated with a printed circuit board. A plurality of contacts of the present invention may be supplied on a carrier strip for ease in assembly of the contacts within the housing. In addition the contacts of the present invention provide a press-fit to the terminal posts or pins of a printed circuit board mechanically and electrically mounting the connector to the printed circuit board. Receptacles in the housing are formed by the noble metal posts or pins and corresponding leaf spring portions of the contacts replacing the complex and fragile stamped and formed metal sockets of the prior art. Substantial conductivity of the receptacles is provided by the noble metal posts, allowing the spring portions to be designed for strength and spring properties with conductivity thereof being a secondary consideration. The press-fit connections of the contacts with posts which are already mounted in the printed circuit board eliminates the need for fabricating additional electrical connections to the circuits of the printed circuit board.

OBJECTS Accordingly it is an object of the present invention to provide a header for a dual-in-line package wherein electrical receptacles are mounted within a dielectric housing which is flexible in order to conform to the irregularities in a printed circuit board surface.

Another object of the present invention is to provide a header for a dual-in-line package in the form of a dielectric housing containing a plurality of leaf springs 2 for cooperating with noble metal posts of a circuit board to provide receptacles in the housing for pluggable receipt of the leads of a dual-in-line package. with the leaf springs further being latched in position within the housing to retain the contacts in desired positions.

Another object of the present invention is to provide an electrical connector of miniature size for mounting on a printed circuit board, the connector being in the form of a dielectric housing containing resilient springs therein which are press-fit over noble metal posts mounted in a printed circuit board and which cooperate with the posts to form electrical receptacles in the housing for wedgingly receiving therebetween the corresponding leads of a dual-in-line package.

Another object of the present invention is to provide an electrical connector containing electrical contacts latchably secured in place therein, with a contact having latching portions for connection to printed circuit board posts and wherein additional resilient portions of contacts cooperate with the posts to form electrical receptacles forgrippingly receiving male electrical terminals inserted through openings in the housing.

Other objects and many attendant advantages of the present invention will become apparent upon perusal of the following detailed description taken in conjunction with the drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged fragmentary perspective with parts illustrated in exploded configuration of a prior art printed circuit board provided with projecting posts over which is mounted an electrical connector according to the present invention.

FIG. 2 is an enlarged fragmentary elevation in section of the component parts of FIG. 1 illustrated in exploded configuration.

FIG. 3 is a fragmentary section of the component parts of FIG. 2 in fully assembled condition.

FIG. 4 is an enlarged fragmentary section taken along the line 44 of FIG. 2.

FIG. 5 is an enlarged fragmentary elevation in section illustrating a press-fit electrical connection according to a preferred embodiment of the present invention.

FIG. 6 is an enlarged perspective of an alternative embodiment of an electrical connector according to the present invention.

DETAILED DESCRIPTION With more particular reference to the drawings there is shown generally at 1 in FIG. 1 a state of the art printed circuit board provided with circuit paths electrically connected to an array of projecting electrical posts 2 which are plated with a noble metal such as gold for good electrical conductivity. As shown in FIG. 2 the posts depend from one surface 4 of the printed circuit board for wiring to be connected between posts to form circuit interconnections according to the practice wellknown in the prior art. The other surface 6 of the printed circuit board is reserved for mounting solid state circuit components in the form of dual-in-line packages for example.

As shown in FIGS. 1 and 2, the typical dual-in-line package is generally illustrated at 8 having an elongated encapsulated portion 10, containing the electrical circuit elements, and depending rows of electrical leads or male terminal 12, which are electrically connected to the solid state circuit elements contained within the encapsulated portion 10. It has been the practice in the prior art to pluggably mount a dualinline package such as the package 8 to the surface of the printed circuit board 6 and to provide a technique for electrically connecting the leads 12 to circuit paths of the printed circuit paths of the printed circuit board. Where permanent connections to the circuits was permitted the leads 12 could be soldered directly to the circuit paths of the printed circuit board. However for ease in replacement or repair, most applications require that the leads 12 be removably connected to the circuit paths of the printed circuit board. In the prior art this has been accomplished by the use of headers in the form of electrical connectors mounted to the printed circuit board and containing conducting sockets for removably receiving the leads 12. The drawbacks of prior art headers was that the sockets were difficult to fabricate in miniature size because of their complexity in shape and their requirement of strength for positively gripping the leads to establish the desired electrical connections. In addition the sockets were of such miniature size that they were too fragile to resist damage from repeated forcible insertion and removal of the leads 12. Further the sockets had to be electrically connected to the circuit pads of the printed circuit board by soldering or by additional hardware. Thus in addition to mounting the headers in place on the printed circuit board it was necessary to perform a sep-. arate operation to electrically connect the sockets with the circuit pads. Also in the prior art it was found necessary to rigidize the housing in order to precisely align the sockets with the spaced leads of the dual-in-line package. The housing therefore was very rigid and bulky and was not able to conform to irregularities in the printed circuit board and irregularities in spacing of the circuit paths to which the prior art sockets were to be electrically connected.

In the present invention, an electrical connector is illustrated generally at 14 in the form of a housing of dielectric material. The housing includes a plurality of inverted dielectric receptacles 16 joined together in parallel rows by a flexible web of dielectric material 18 integral with each of the receptacles 16. The flexible web permits individual orientation of the receptacle 16 independent of one another, with the web further being flexible to premit such individual orientation and to conform to irregularities in the surface 6 of the printed circuit board 1 when the housing 14 is mounted thereon in a manner to be explained.

As shown more particularly in FIGS. 2, 3, and 4, the receptacles 16 include

sidewalls

20, 20', 22 and 22' defining internal cavities 24. A plurality of electrical contacts generally shown at 26 are mounted within the interior of the housing 14. More particularly, the contacts 26 are mounted within corresponding internal cavities 24 of the individual receptacles 16. Each of the contacts 26 include a base portion 28 and an integral elongated cantilever beam or leaf spring 30. The base portion 28 of each contact is further provided with a central aperture 32 therethrough with a pair of integral diagonally projecting tabs or lances 34 which are struck from the base portion to project diagonally toward each other. The lances or tabs 34 as particularly shown in FIG. 5 include sharp corner edges 36 for a purpose to be described hereinafter. With more particular reference to FIGS. 2, 3, and 4, the assembly details of the contacts 26 within the receptacles 16 will be explained. The internal cavity 24 of each inverted receptacle extends through the bottom of the receptacle to define an least portions of each of the walls 22 and 22'. Since the bottom wall 38 only overlies portions of the sidewalls:

22 and 22', the peripheral sidewall 40 of the recess terminates short of the sidewall 24 of the receptacle. The sidewall 40 of the recess is provided with a plurality of arcuate compressible projections 42 which may .be.

molded integrally with the receptacle 16. The sidewall 40 of each recess is complementary in shape to the pe riphery of a corresponding contact 26. More particu larly each of the contacts .26 includes a generally square base as shown. Accordingly the sidewall 42 defines a complementary square recess for receipt of the Y base 28 of a corresponding contact therein. The base portion of a contact is forcibly'inserted into the recess,

compressing the projections 42 momentarily. When the base portion 28 is in registration against the bottom wall 38, the projections 42 will overlie the edge margins of the base portion to lock or latch the contact in place. Each contact is press-fit into a corresponding receptacle l6 and has the base portion fully exposed from the 1 bottom of the receptacle for ease in removal or replacement in case of damage thereto. The square con figuration of the base portion prevents rotational movement of the contact from its desired position in the receptacle asshown. The projecting leaf spring or cantilever beam 30 of the contact is located generally verti-.

cally within a corresponding receptacle 16. Each beam 30 is reversely curved along its length to provide a rounded contact surface 44 adjacent to an outwardly flared end portion 46. To complete the connector 14,

each of the receptacles is provided with a generally tapered and reduced opening or entrance aperture 48 through the top wall 50 of each receptacle and along an axis extending between the aperture 32 and the beam 30.

The opening in the bottom of each receptacle -16 fully exposes the base portion and also the aperture 32 of the base portion. When the connector 14 is mounted to the surface 6 of the printed circuit board 1, the apertures 32 of the contacts 26 will receive corresponding posts 2 therein. The posts 2 are of a configuration whereby they project outwardly on both sides of the printed circuit board 1. As shown more particularly in FIGS. 3 and 5, when a corresponding post is received through the aperture 32 of a corresponding contact, the diagonally projecting lances 34 will wedgingly engage opposite sides of the post 2 forcing their sharp corner edges 36 to engage and bite the post and thereby lockingly or latchingly retaining the housing and contacts in position on the printed circuitboard. Each contact is thus force-fit or press-fit over, a corre-:

sponding post to provide both a mechanical and electrical connection thereto. Such a connection isacconi:

plished merely by the press-fitting assembly over corresponding posts, thereby eliminating the need for a sepacles 16 was individually freely movable to allow for flexibility of the connector. Ordinarily. this would cause the spacings between the contacts of the connector to vary, making it difficult to simultaneously plug the plu-.

rality of leads of a dual-in-line package into the connector. However, once the contacts of the connector are forced-fitted over corresponding posts 2, the contacts and the individual receptacles will be maintained in rigid desired alignment, with the individual receptacles being allowed a degree of freedom by warpage of the web 18 only to permit ease in assembly over the posts and to vary slightly in height when mounted over surface of regularities of the printed circuit board.

As shown more particularly in FIGS. 2 and 3, a post 2 within each ofv the receptacles 16 extends adjacent a substantial length of a .corresponding beam 30. The adjacent beam 30 and post 2 within a corresponding re-.

ceptacle l6 cooperate to provide therebetween a grip ping type receptacle. More particularly, the opening or aperture 48 in the top wall 50 of a receptacle '16 is positioned on an axis extending generally between a cooperating post 2 and beam 30. When the leads 12 of a dual-in-line package 8 are pluggably inserted or received within the corresponding receptacles 16 of the connector 14, each lead 12 will enter a corresponding entrance 48 and will be pluggably inserted into the internal cavity 24 of the receptacle l6 and will thus lie along the axis extending generally between a cooperating post 2 and beam 30. Each of the beams 30 has its free end 46 curved outwardly away from such axis and accordingly away from the post 2. This prevents snagging of the corresponding lead 12 on the end 46 as the lead 12 enters between the beam 30 and corresponding cooperating posts 2. The beam 30 is fabricated from resilient metal and accordingly is slightly resiliently deflected away from the post 2 by the presence of the lead 12. The resilient beam thus resiliently compresses or clamps the lead 12 between the beam 30 and the post 2 to provide a mechanical and electrical connection at least between the post, and the lead 12. The noble metal post is adequate for establishing the desired electrical contact with the lead 12. The beam 30 thus can be selected from a metal with good spring properties; conductivity of the metal being of secondary importance. Accordingly the rigid post 2 and the resilient beam 30 provide atwo-sided clamping receptacle for receipt of a male terminal or lead 12 therein. The arcuate contact surface 44 of the beam 30 will engage the lead 12. The rigid post 2 provides a force-fitted connection of the contact 26 to the printed circuit board while simultaneously electrically connecting the lead 12 to the circuit pads of the printed circuit board. The posts additionally provide a rigid means for assuring alignment of the individual flexibly interconnected receptacles 16 of the connector housing. In addition, each post cooperates with a resilient beam to form an electrical receptacle. The post comprises a rigid structure against which an inserted male terminal or lead may be impinged and pressed. The post therefore lends rigidity to the electrical receptacle preventing damage thereof by repeated insertion and forceable withdrawal of the male terminal or lead. The resilient beam 30 itself is a simple cantilever beam or leaf spring enabling it to be of sufficient strength to withstand repeated resilient deflection by the insertion and withdrawal of the male terminal or lead.

An alternative housing is illustrated generally at 52 in FIG. 6. The housing comprises a pair of elongated receptacles 54 interconnected by a flexible web 56. Each of the receptacles 54 includes a plurality of contacts similar to the contact 26. In this alternative embodiment the receptacles are still individually flexible about the flexible web 56, but are molded such that an entire tacle row of contacts 26 are contained within a single recep- Although preferred embodiments and modifications thereof have been described and shown indetail, it is understood that additional modifications and embodiments are intended to be covered by the spirit and scope of the appended claims. 7

what is' claimed is: l. A connector, comprising: w A a dielectric housing having sidewalls defining an internal cavity,

a top wall of said housing having a tapered entrance 7 communicating with said cavity,

a bottom wall of said housing having an opening communicating with said cavity, a I r an enlarged recess ,in thebottom wall of said housing communicating with said opening, I integral projections on the housing projecting into said recess, H an electrically conducting terminal having a base portion received in said recess and having a resilient cantilever beam portion integral with said base,

said projections overlying the edges of said base portion to retain the base portion in said recess,

an aperture in said base portion in alignment with said opening,

a pair of locking tabs adjacent said aperture,

said aperture adapted to receive an electrically conducting post therethrough, said tabs adapted to lockingly engage a post received through said aperture, and said beam adapted for resilient compression on a male terminal received between said post and said beam.

2. A connector, comprising:

a dielectric housing having an internal cavity,

means having a resilient beam in said cavity and a base portion latched to said housing, said base portion having an aperture and a pair of opposed locking lances adjacent said aperture for locking onto a male terminal,

said housing having a first opening adjacent said base for receiving a first male terminal in locked receipt with said lances, and

said housing having a second opening adjacent said beam, the second opening of said housing being located on an axis extending between said first male terminal and said beam to permit receipt of another male terminal in said second opening in gripped relationship between said first male terminal and said beam.

3. In the combination of a printed circuit board and a connector mounted thereon, the improvement comprising:

an array of electrically conducting posts on said printed circuit board connected respectively to circuit paths on said printed circuit board,

said connector comprising a dielectric housing receiving therein at least portions of said posts, electrical contacts in said housing having first latching portions latched on said posts,

said contacts having resilient second portions separate from said latching portions, and

each of said resilient second portions opposing a corresponding post and cooperating with a corresponding post to form an electrical receptacle adapted for gripping receipt of a male electrical terminal pluggably received by said housing.

4. The structure as recited in claim 3. wherein. said housing comprises a plurality of individual receptacles joined together by a flexible web. each of said rcceptacles having an internal cavity for receiving at least one of said posts and at least one of said resilient portions of said contacts therein.

5. The structure as recited in claim 3, whereinv each of said latching portions comprises an aperture receiving a corresponding post and a pair of opposed locking tabs adjacent said aperture lockingly engaged on a corresponding post.

6. The structure as recited in claim 3, wherein, each of said contacts is latchingly engaged in and thereby rctained in said housing.

7. The structure as recited in claim 3, wherein, each of said resilient portions comprises an elongated cantilever beam.

8. The structure as recited in claim 7, wherein, each cantilever beam is tapered toward its free end.

9. A connector. comprising: I r a dielectric housing having an internal cavity. an electrically conducting terminal latchingly retaine in said internal cavity,

said terminal having a first portion provided: with locking means whereby said locking means is capa- I ble of locking engagement on a post received within said internal cavity of said housing,

said terminal includes a resilient portion separate from said locking means, and i said housing having an entrance opening commun i-r

Claims

1. A connector, comprising: a dielectric housing having sidewalls defining an internal cavity, a top wall of said housing having a tapered entrance communicating with said cavity, a bottom wall of said housing having an opening communicating with said cavity, an enlarged recess in the bottom wall of said housing communicating with said opening, integral projections on the housing projecting into said recess, an electrically conducting terminal having a base portion received in said recess and having a resilient cantilever beam portion integral with said base, said projections overlying the edges of said base portion to retain the base portion in said recess, an aperture in said base portion in alignment with said opening, a pair of locking tabs adjacent said aperture, said aperture adapted to receive an electrically conducting post Therethrough, said tabs adapted to lockingly engage a post received through said aperture, and said beam adapted for resilient compression on a male terminal received between said post and said beam.

2. A connector, comprising: a dielectric housing having an internal cavity, means having a resilient beam in said cavity and a base portion latched to said housing, said base portion having an aperture and a pair of opposed locking lances adjacent said aperture for locking onto a male terminal, said housing having a first opening adjacent said base for receiving a first male terminal in locked receipt with said lances, and said housing having a second opening adjacent said beam, the second opening of said housing being located on an axis extending between said first male terminal and said beam to permit receipt of another male terminal in said second opening in gripped relationship between said first male terminal and said beam.

3. In the combination of a printed circuit board and a connector mounted thereon, the improvement comprising: an array of electrically conducting posts on said printed circuit board connected respectively to circuit paths on said printed circuit board, said connector comprising a dielectric housing receiving therein at least portions of said posts, electrical contacts in said housing having first latching portions latched on said posts, said contacts having resilient second portions separate from said latching portions, and each of said resilient second portions opposing a corresponding post and cooperating with a corresponding post to form an electrical receptacle adapted for gripping receipt of a male electrical terminal pluggably received by said housing.

4. The structure as recited in claim 3, wherein, said housing comprises a plurality of individual receptacles joined together by a flexible web, each of said receptacles having an internal cavity for receiving at least one of said posts and at least one of said resilient portions of said contacts therein.

5. The structure as recited in claim 3, wherein, each of said latching portions comprises an aperture receiving a corresponding post and a pair of opposed locking tabs adjacent said aperture lockingly engaged on a corresponding post.

6. The structure as recited in claim 3, wherein, each of said contacts is latchingly engaged in and thereby retained in said housing.

9. A connector, comprising: a dielectric housing having an internal cavity, an electrically conducting terminal latchingly retained in said internal cavity, said terminal having a first portion provided with locking means whereby said locking means is capable of locking engagement on a post received within said internal cavity of said housing, said terminal includes a resilient portion separate from said locking means, and said housing having an entrance opening communicating with said cavity whereby a male terminal pluggably inserted in said opening may be received in resilient gripped relationship between said resilient portion and a post lockingly engaged by said locking means.