Electrical Connector Assembly

Abstract

An electrical connector assembly for interconnecting an electrical circuit element having a plurality of electrical contacts extending therefrom with a printed circuit board having a plurality of openings therein. The connector assembly comprises an insulated housing member mounted on the board and formed with a plurality of compartments each receiving an electrical contact which is mounted in an opening in the board. Each contact has a mounting section positioned in the opening, a generally hook-shaped blade section extending upwardly from the mounting section and terminating in a free end, and a wire-wrap tail extending downwardly from the mounting section. Slots in the housing open into the compartments above the blade sections for receiving the electrical leads from the electrical circuit element. Abutment means is provided in each of the compartments to engage each of the free ends of the contacts to preload the contacts. The contacts releasably retain the housing on the board.

Description

BACKGROUND OF THE INVENTION

This invention relates generally to an electrical connector assembly and, more particularly, to such an assembly for interconnecting an electrical circuit element having a plurality of electrical contacts extending therefrom with a mounting member having conductive openings therein.

The present invention will be described specifically with respect to a connector assembly for interconnecting an electrical circuit member, referred to in the art as a dual in-line plug, to a mounting member such as a printed circuit board. However, it will be appreciated that the connector assembly of the invention could be used for interconnecting other types of circuit elements to mounting members.

The connector assembly of the type to which this invention relates is often referred to as a dual in-line package socket. Conventionally, such a socket consists of a two-piece molded dielectric body or housing. Individual contacts for each lead of the dual in-line plug are provided in the housing. The contacts are assembled into one portion of the body, and then the other half of the body is bonded or snapped onto the contact body assembly. This type of construction results in a multiplicity of components which raises the cost of the finished product. Further, the finished part is relatively large, that is, requires more volume than is absolutely necessary. These two latter-mentioned considerations are of major importance for components used in high density packaged, high production volume electronic units. Also, in conventional dual in-line packaged sockets, the contacts are soldered into the printed circuit board. This is disadvantageous in that solder often remains on the wire-wrap posts of the contacts and individual soldering of contacts into the printed circuit board is relatively expensive. Also, the solder must be removed from the contacts in order to replace them. Still further, special fastening means is usually required to hold the socket on the board.

The purpose of the present invention is to overcome the attendant disadvantages of the prior art dual in-line packaged socket by providing a structure which is simple in construction, thereby minimizing production cost by eliminating components and permitting the use of high production techniques with a minimum of assembly required. More particularly, by the present invention, the cost and inconvenience of utilizing soldering techniques to fix the socket contacts in the printed circuit board is eliminated. In addition, the contacts are automatically preloaded when the socket is mounted on the board and the contacts serve to releasably retain the socket on the board.

SUMMARY OF THE INVENTION

According to the principal aspect of the present invention, there is provided an electrical connector assembly for interconnecting an electrical circuit element having a plurality of electrical contacts extending therefrom with a mounting member having a plurality of openings therein. The connector assembly comprises an insulated housing member positioned on the mounting member and formed with a plurality of compartments each receiving an electrical contact which is mounted in an opening in the mounting member. Each contact has a mounting section positioned in the opening, a generally hook-shaped blade section extending upwardly from the mounting section and terminating in a free end, and a lower end section extending downwardly from the mounting section. Slots in the housing open into the compartments above the blade sections for receiving the electrical leads from the electrical circuit element. Abutment means is provided in each of the compartments to engage each of the free ends of the contacts to preload the contacts. The contacts are initially press-fitted into the openings in the mounting member. Thereafter, the housing member of the connector assembly is mounted over the contacts flush with the board to automatically preload the contacts simultaneously. The contacts serve to releasably retain the housing member on the mounting member. Thus, soldering and special fastening devices are eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating an electrical circuit element positioned to be mounted in an electrical connector assembly constructed in accordance with the present invention, such assembly being positioned on a planar mounting member;

FIG. 2 is an enlarged transverse cross-sectional view of the connector assembly shown in FIG. 1 positioned on the mounting member with one lead of the electrical circuit element inserted in a compartment of the connector assembly fully engaged with a contact therein;

FIG. 3 is a plan view of a die stamping of a plurality of contacts connected to a common carrier strip prior to forming of the contacts into their final configuration;

FIG. 4 is an end view of the stamping illustrated in FIG. 3;

FIG. 5 is an end view of the stamping after it has been formed into the desired configuration; and

FIG. 6 is a perspective view of the mounting member upon which the electrical connector assembly of the invention is adapted to be mounted, with a plurality of contacts mounted in one row of openings in the mounting member with the carrier strip still joining the contacts.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1 in detail, there is shown the electrical connector assembly or socket of the present invention, generally designated 10, which may be used to interconnect an electrical circuit member 12 to a mounting member 14. The electrical circuit element 12, which may be a dual in-line plug, has a plurality of electrical leads 16 which extend laterally outwardly from opposite sides of the element and downwardly below the lower surface of the element. The element 12 may be an integrated circuit or other electrical circuit component.

The mounting member 14 is a printed circuit board which may be either a single layer, as shown, or multi-layered in construction. The board is formed with two rows of openings 18 therein which are plated-through with a conductive metal coating as well known in the art. The connector or socket assembly 10 comprises a hollow housing or shell 20, generally rectangular in configuration and preferably formed as an integral plastic molding. The housing includes a pair of side walls 22 and an intermediate upstanding wall 24 spaced from the side walls. Transverse walls 26 and end walls 27 define two rows of separate compartments 28 for receiving electrical contact elements 30. If desired, the housing could be divided longitudinally into two separate strips each having a row of compartments therein. In this case, the two strips could be joined together in any suitable manner, such as by hubs in one strip tightly engaged in openings in the other strip.

Slots 32 are formed in the upper wall 34 of the housing 20 and open into the upper portion of the compartments 28. Passages 36 in the lower portion of the housing 20 communicate the compartments 28 to the lower surface 38 of the housing. The two rows of compartments 28 are arranged in a pattern so that the slots 32 will be in registry with the leads 16 of the electrical circuit element 12 when the latter is properly positioned over the housing and the passages 36 will be in alignment with the openings 18 in the mounting member 14.

The contacts 30 in the two rows of compartments 28 are identical in structure but are mounted in the openings 18 in the mounting member 14 so as to face in opposite directions as best seen in FIG. 2. Each contact includes a central mounting section 40 which is positioned in an opening 18 in the mounting member 14, a hook-shaped resilient blade section 42 which extends upwardly from the mounting section and terminates in a free end 44, and a relatively rigid lower end section or terminal portion 46 which extends downwardly from the mounting section. The terminal portion 46 is generally square in cross-section and may be tapered at its tip end 48 to facilitate insertion of the contact into the openings 18. The terminal portion 46 is often referred to as a wire-wrap tail.

The central mounting section 40 is slightly wider than the blade section 42 at the junction of the two sections so as to define an upwardly facing shoulder 50 as best seen in FIG. 3. A tapered transitional section 52 provides the width transition between the terminal portion 46 and the lower end 54 of the mounting section 40. The lower end 54 of the mounting section is not as wide as the upper end 56 and preferably is undercut as indicated at 58 immediately below the upper portion to define a downwardly facing shoulder 60. The width of the lower end 54 is dimensioned so that an interference fit is provided between the contacts and the openings 18 when the contacts are forced into the openings. When a contact is forced into an opening 18, the shoulder 60 will rest on the top surface of the mounting member 14, correctly positioning the contact thereon.

The blade section 42 of each contact 30 includes a generally straight, vertically extending root portion 62 adjacent to the mounting section 40, an upper reverse-bent portion 64 and a convex spring contacting portion 66 between the reverse-bent portion 64 and the free end 44 of the contact. Preferably the blade section is formed with a lower concave portion between the convex contacting portion 66 and the free end 44.

The contacts 30 are made from a single, long, thin sheet of metal, such as a phosphorus bronze, joined by a common carrier strip 70, as best seen in FIGS. 3 and 4. The contacts are initially stamped from a flat sheet in planar form and thereafter are formed into proper configuration, as seen in FIG. 5, while the individual contacts are still joined together by the carrier strip 70. The contacts are slightly bevelled to a reduced section 72 where the contacts are connected to the carrier strip 70 which allows the strip to be broken away from the contacts after the latter are press-fitted into the openings 18 in the mounting member 14. As will be noted in FIGS. 4 and 5, the blade section 42 of the contacts has a thickness less than that of the remainder of the contacts to provide the spring contacting portion 66.

To mount the contacts in the openings 18 of the mounting member 14, a plurality of contacts joined by the carrier strip 70 are initially positioned over the openings in alignment therewith. A suitable tool, not shown, is then brought into engagement with the shoulders 50 on the mounting sections of the contacts and moved vertically downwardly to press-fit the mounting portions of the contacts into the openings until the shoulders 60 engage the upper surface of the mounting member 14, as seen in FIG. 6. Thereafter, the carrier strip 70 is broken away at the bevelled sections 72. Thus, the contacts are rapidly mounted in the support member 14 since the plurality of the contacts are inserted simultaneously. It will be understood, however, that if desired, the contacts could be mounted separately into the openings 18 in the mounting member.

The housing 20 is mounted over the contacts onto the mounting member 14 after the contacts have been press-fitted into the openings 18. To this end, the passages 36 in the housing 20 are sufficiently wide so that when the housing is initially mounted on the contacts, the upper reverse portion 64 of the contacts will extend a short distance into the passages. The outer wall portion of the passages 36 adjacent the lower surface 38 of the housing are bevelled as indicated at 74, so that upon downward movement of the housing, the spring contacting portions 66 of the contacts will deflect inwardly a sufficient distance to allow the lower portion of the housing to pass downwardly over the contacting portions of the contacts. An inwardly facing ledge 76 is formed on the inner surface of the side wall 22 of each compartment 28 in the housing adjacent to but spaced above the lower surface 38 of the housing to provide a vertically extending abutment shoulder 78. This shoulder is engaged by the free end 44 of each contact after the housing is mounted over the contacts flush with member 14 as seen in the left side of the assembly shown in FIG. 2. The engagement of the free ends 44 of the contacts with the shoulders 78 preloads the contacts.

When the housing 20 is mounted over the contacts 30, the convex contacting portions 66 of the contacts extend into the area of the compartments 28 immediately below the slots 32 so that when the contact leads 16 of the electrical circuit element 12 are inserted into the slots, the leads will engage such contacting portions of the contacts. As seen in the right side of the assembly shown in FIG. 2, when a lead 16 is inserted through the slot 32, the contacting portion 66 of the contact 30 will deflect inwardly, removing the free end 44 of the contact off the ledge 76. Preferably, an inclined ramp 80 is formed between the inner surface 82 of the side wall 22 and the shoulder 78 formed by ledge 76. Thus, as the tip of lead 16 engages the ramp 80, the lead will be shifted into tight engagement with contact 30.

Thus, by the present invention, the contacts 30 are mounted in openings in the mounting member 14, and the housing 20 is thereafter mounted over the contacts to preload the contacts simultaneously. Since the contacts are press-fitted into the mounting member 14 and the free ends 44 of the contacts engage the ledges 76 of the housing, the housing is firmly retained on the mounting member by the contacts. In order to remove the housing from the mounting member, a tool, not shown, having two rows of fingers positioned in a manner like the leads 16 of the circuit element 12, is positioned over the connector assembly 20 and moved downwardly so that the fingers will remove the free ends of the contacts from the ledges 76 whereupon the assembly 20 may be raised to remove the same from the contacts and the mounting member 14. This allows for easy replacement of a contact if desired. Also, by the present invention, there is no necessity of making solder connections between the contacts and the supporting member, thus minimizing manufacturing costs and eliminating the problem of solder remaining on the contact tails 46.

Claims

What is claimed is:

1. An electrical connector assembly for receiving an electrical circuit element having electrical leads extending therefrom comprising:

a planar mounting member having openings therein:

an electrical contact mounted in each of said openings, said contact having a mounting section press-fit into said opening, a generally hook-shaped blade section extending upwardly from said mounting section and terminating in a free end, and a lower end section extending downwardly from said mounting section, said hook-shaped blade section including an upper reverse bent portion and a convex contacting portion between said reverse bent portion and said free end;

an insulated housing member on said mounting member having a plurality of compartments receiving said hook-shaped blade sections of said contacts, said compartments opening at the bottom of said housing member and being dimensioned to slidably receive said contact hook-shaped blade sections thereinto from said bottom thereby permitting said housing member to be mounted over said contacts onto said mounting member, said housing member having a side wall adjacent to said contacting portions of said contacts and an upper wall, said upper wall extending over said reverse bent portions of said contacts, slots in said upper wall adjacent to said side wall opening into said compartments above said contacting portions for receiving the electrical leads of said electrical circuit element, and abutment means in each of said compartments engaging each of said free ends to preload said contacts and to retain said contacts within said compartments whereby said housing member is retained on said mounting member by said contacts, said abutment means comprising a ledge formed on said side wall adjacent to the bottom of said housing member, said ledge providing an upwardly facing horizontal surface and an upstanding shoulder in each said compartment engaged by said free end of said contact.

2. An assembly as set forth in claim 1 wherein:

said free end is reversely bent with respect to said convex contacting portion.

3. An assembly as set forth in claim 1 wherein:

said shoulder extends vertically; and

said free end of each said contact embodies a vertical surface engaging said shoulder.