WO1999017407A1

WO1999017407A1 - Shielded connector with pcb boardlock

Info

Publication number: WO1999017407A1
Application number: PCT/IB1998/001513
Authority: WO
Inventors: James Johnstone; Barry Thomas Rodger; Stephen John Wrigley; Jim Braithwaite
Original assignee: The Whitaker Corporation
Priority date: 1997-09-30
Filing date: 1998-09-30
Publication date: 1999-04-08
Also published as: AU9180698A

Abstract

A shielded connector comprises an integral shield member (6) made of a relatively ductile material in order to form the deep drawn mating portion (22). The shield member has a boardlock (20) integrally formed therewith. The boardlock (20) is engaged by spring support beams (50) of the housing in order to enhance the resiliency of the boardlock and improve positioning on a circuit board prior to soldering.

Description

SHIELDED CONNECTOR WITH PCB BOARDLOCK

This invention relates to a connector with a shielding shell, for mounting on a circuit board, the connector provided with a boardlock.

It is known to provide connectors with stamped and formed shielding shells, where the shell has integral legs that plug into a plated through-hole of a printed circuit board (PCB) for mechanical and electrical connection thereto. It is known to provide the legs in the form of a boardlock that provisionally holds the connector to the circuit board during assembly, prior to soldering of the connector to the circuit board. Connection of the shielding shell to the circuit board provides an electrical ground connection for the connector shielding, and an additional mechanical connection of the connector to the PCB. In many connectors, the shielding shell is made of ductile metal that is easy to stamp and form, and particularly to form by deep-drawing. Boardlocks integrally formed with shielding shells made of a ductile metal often have insufficient resiliency to guarantee a secure and accurate location of the connector on the board. A loosely mounted connector may be soldered out of position, which is undesirable.

It is an object of the invention to provide a shielded connector with a boardlock that enables secure and accurate location of the connector on a board or panel, or the like. It would be further desirable to enable assembly of the connector to a PCB by simply plugging the connector on the board and subsequently soldering. It would be desirable to provide a cost effective connector to manufacture, assemble and handle. Objects of this invention have been achieved by providing the connector according to claim 1. Disclosed herein is a shielded connector comprising an insulative housing, a shielding member, and one or more boardlocks, each said boardlock having a plurality of mounting portions pluggable into a hole of a circuit board or panel for electrical and mechanical connection to the board or panel, each said boardlock having one or more support member for biasing the mounting portions against edges of the circuit board hole, wherein at least one of the mounting portions is electrically conductive and electrically interconnected to the shielding of the connector, and the support member form part of the insulative housing thereby providing enhanced resiliency of the boardlock arms. Advantageously therefore, dependency on the resilience of a relatively ductile shielding material is reduced or eliminated, and resilient mechanical securing of the connector to a circuit board is enhanced prior to soldering. Once soldered, the solder connection between the conductive mounting portion and the board securely locks the connector to the board in addition to electrically interconnecting the shielding to the board.

The housing spring support members may be in the form of spring beams, for example in the shape of cantilever beams integrally attached to a wall of the housing and extending to free ends that engage arms of the conductive boardlock mounting portions. The boardlock may comprise a pair of arms in substantially mirror image disposition between which the resilient portion in the form of housing support spring arms engage. The conductive boardlock arms may be separate from each other at their locking ends, although it is also possible to provide a boardlock that is bridged at the locking end. The spring support arms of the housing, and the boardlock may be designed such that substantially all or most of the resiliency is provided by the spring support members, thereby enabling stamping and forming of the boardlock in a cost effective and simple manner. For example, the boardlock may be provided with thin sections integrally interconnecting the boardlock to the shield member, the thin sections enabling easy and accurate bending of the boardlock into a vertical position for plugging into a circuit board hole. The shielding member may be an integral stamped and formed part having a deep drawn section in the form of a shroud that encloses a terminal receiving portion of the housing, because the provision of housing spring support for the boardlock enables the shield member to be stamped and formed from a ductile material.

In another embodiment the support member is positioned between extensions of the boardlock arms to encourage torsional flexing of the boardlock and enhance the elastic range thereof.

In yet another embodiment, the resilient portion may comprise resilient boardlock arms with mounting portions, integrally formed with the insulative housing, that serve to secure provisionally the connector to the board, whereas a further boardlock arm is conductive and interconnects the conductive mounting portion to the shielding shell of the connector.

Further advantageous aspects of the invention are set forth in the claims, or will be apparent from the following description and drawings.

Embodiments of this invention will now be described by way of example with reference to the figures in which; figure 1 is a rear isometric view of part of a connector according to this invention; figures 2-6 are isometric views of the shielding shell during manufacturing steps thereof, and assembly of the shielding shell to an insulative housing, the figures

2-6 showing successive steps in the manufacturing and assembly; figure 7 is a partial isometric view of another embodiment according to this invention; figure 8 is a side view of the embodiment of figure 7; figure 9 is a rear view of part of the connector of figure 7 mounted to a PCB shown in cross-section; figure 10 is front plan view of part of another connector embodiment according to this invention; figure 11 is a detail cross-sectional view through line 11-11 of figure 10; figure 12 is a perspective view of part of the connector of figure 10 with the shielding shell of the connector about to be mounted to the housing having a boardlock mounting portion shown in cross-section; figure 13 is a perspective view of the connector of figure 12 in the assembled state with the boardlock mounting portion of the housing shown in partial cross- section; figure 14 is a plan view in cross-section through line 14-14 of figure 10.

Referring to figures 1-6, particularly figure 1, an electrical connector 2 comprises an insulative housing 4 and a shield member 6. The insulative housing 4 extends from a mating face 8 to a terminal receiving face 10 and has cavities extending therethrough for receiving terminals therein. The terminals and terminal receiving cavities are not shown, however it should be understood that such features may be similar to those of a conventional connector. The connector 2 is for mounting on a printed circuit board, or a panel, or the like, which is not shown, but that mounts against a mounting face 12 of the connector, the mounting face 12 facing in a direction perpendicular to the mating face 8. The invention described herein could also apply to a connector where the mounting face 12 faces in any other direction. The connector housing 4 comprises a mating portion 14 and a mounting portion 16 ( see figure 4) .The mating portion 14 is provided with the terminal receiving cavities for receiving mating portions of the terminals therein. The mounting portion 16 extends rearwardly from the mating portion 14 and comprises the mounting face 12 that is positioned adjacent the printed circuit board when the connector is assembled thereto. The housing mounting portion comprises a boardlock section 18 that receives a boardlock 20.

The shield member 6 comprises a mating portion 22 in the form of a shroud that surrounds the mating portion 14 of the housing. The shield mating portion 22 extends from the mating end 8 to an intermediate face 24 where the shield member comprises a flange 26 extending substantially orthogonally to the mating portion 22. The flange 26 is in a plane corresponding substantially to the plane of the sheet metal from which the shield member is stamped and formed. The mating portion 22 is formed from the plane of the sheet metal as best seen in figure 2 as a single integral part that is deep drawn by stamping in a number of successive stages of a stamping die. Deep drawing is facilitated by employing relatively ductile material, particularly in order to reduce the formation of cracks during the forming process. Provision of an integral shield member having both the mating portion and flange, and boardlock 20, significantly reduces manufacturing costs, and in particular the costs of assembling the connector components. The flange 26 comprises means 28 which may be a threaded screw hole, for fixing a mating connector thereto, as is typical with conventional connectors. The boardlock 20 is interconnected to the flange 26 via a support section 30 extending substantially orthogonally from the flange 26, arranged proximate an end 32 of the connector. The support section 30 is bent through a 90 degree corner 32 from the flange 26 and is seated between support walls 34, 36 of the housing forming a gap therebetween for receiving the support section 30. The support section 30 comprises a pair of spaced apart thin sections 38 separated by a cut-out 40 that enhances the ease of bending of the support section from the flange 26. The bending operation of the support section from the flange is illustrated in figure 3. In addition, the material removed from the cut-out 40 enables provision of useful functional elements such as stamped-out fixing tabs 42 that cooperate with complementary clips of a mating connector.

During the forming process, the boardlock 20 is initially bent with the support section 30 as shown in figure 3, whereby the boardlock 20 and support section 30 is insertable in the gap between the housing support walls 36, 34 as shown in figures 4 and 5. Subsequently as shown in figure 6, the boardlock is bent 90 degrees into the vertical position for plugging into a circuit board received against the mounting face 12. The latter also securely fixes the shield to the connector housing. The boardlock 20 comprises a pair of arms 44 that extend from corner portions 46 where the arms are integrally connected to the support section 30. The housing lower support wall 34 has an arcuate corner 47 that supports the corner portions 46 during forming thereof i.e. when the boardlock 20 is bent into the vertical position. The corner portions 40 are separated by a gap 48 such that the corner portions 46 are thin strips, thinner than the major portion of the boardlock arms 44, in order to favourise bending at the corner portions 46 during the bending operation of the boardlock. In conjunction with the arcuate support surface 47 of the housing, the latter ensures an accurate positioning of the boardlock by accurately controlling the bending location thereof. The thin corner portions 46 can be provided because of resilient support of the boardlock arms 44 by resilient or spring support members 50 of the housing as will be described hereinafter. The pair of boardlock arms 44 comprise a housing engagement portion 52 separated by a gap 53 defined by inner edges 54 of the arms 44, the boardlock arms further comprising a mounting portion 56 extending to a free end 57. Proximate the free end 57 are protrusions 58 bulging outwards and forming with the free end a tapered guide surface 59 for assisting plugging of the boardlock through a hole of a circuit board or panel or the like, further forming a rear tapered retention surface 60 for engaging a lower edge of a hole in the circuit board thereby retaining the connector to the board. The tapered retention surface 60 draws the connector mounting face 12 securely against the board when a force is applied to the arms 44 tending to separate them.

The resilient support members 50 are provided with engagement portions 62 engaging the inner edges 54 of the boardlock, for resiliently outwardly biasing the arms 44. The engagement portions 62 are provided at ends of the spring support members 50, which are in the form of cantilever beam arms integrally attached at an attachment end 64 to the housing 4, and in particular to an intermediate wall 66 of the housing. The engagement portions 62 extend beyond a rear location face 68 of the support members that serves to accurately position the boardlock arms 44 thereagainst when the boardlock 20 is bent to the vertical position. The location face 68 and thin corner portions 46 of the boardlock thus co-operate to enable precise location of the boardlock whilst enabling simple manufacturing thereof. The spring support member in this embodiment provides a substantial proportion of the spring force of the boardlock arms 44, thus enabling greater choice of shielding material and design of the boardlock arms. It would also be possible to provide a housing spring member between the boardlock arms, that is not integrally formed with the housing. Other spring designs may be provided, such as a tubular or elliptical member seated between the boardlock arms against the edges 54, whereby the resiliency is derived from radial squeezing of the tube. In this embodiment, the free ends 57 of the boardlock arms 44 are separated, however it would possible to have another embodiment where the free ends are joined by a bridging portion that allows some pivotal bending of the two arms about the bridging portion.

In the preferred embodiment, the provision of the cantilever beam spring arms 50 extending integrally from the housing and engaging the boardlock arms when they are bent 90 degrees into the fully manufactured position as shown in figure 1, provides for a particularly reliable yet easy to manufacture connector. In addition, in view of the few parts, a particularly cost effective arrangement is achieved. Whilst the connectors of figures 2-6 shows one boardlock, the connector may be provided with a pair of boardlocks, one on either end of the connector, which would be the preferred embodiment. Alternatively, one boardlock may be provided on one end, the other end having a second boardlock formed directly from the housing. The boardlock also serves as an electrical interconnection between the shield member and a ground conductor on the board.

It is also possible to provide the boardlock as a separate member from the shield member but electrically connected thereto. The shield member may be made of more than one part, depending on functional needs and manufacturing costs. A preferred low-cost embodiment however has the shield member and boardlocks as an integral single part.

Referring to figures 7-9, another embodiment is shown, which comprises the same or similar features to the connector of figures 1-6 except for the design of the boardlock. The numbering of identical or similar parts will be maintained and the description of parts given the same numbers in figures 7-8 as in figures 1-6 may be taken form the description above referring to the embodiment of figures 1-6. Only the major differences will be described hereinafter. The boardlock 20' comprises a pair of arms 44' arranged in a first plane, and a pair of arms 44' ,44'' arranged in a second plane orthogonal to the first. Three of the arms 44' are integrally formed with the housing 4' and are resilient. Resiliency is provided by spring support members 50' in the form of cantilever beam arms attached at one end to the housing, for example by integral moulding therewith. The three arms 44' have mounting portions 56' proximate free ends 57' . The mounting portions have enlargened portions or protrusions 58' , with tapered retention surfaces 60' for engaging a lower corner 80 of a PCB through-hole 82, for securing the boardlock thereto. One of the arms 44'' is conductive, and could be integrally stamped and formed with the shield member 6 of the connector 2 in a similar manner to the embodiment of figures 1-6. Alternatively, the arm 44'' could be a separately formed piece of metal that engages the shield member, for example by plugging through a hole of the shield member in an interference fit. The conductive arm 44'' comprises a mounting portion 56'' proximate a free end 57''. The mounting portion has an enlargened portion or protrusion 58'', with a retention surface 60'' for engaging the lower corner 80 of the PCB through-hole 82.

The arm 44' facing the conductive arm 44'' in the second plane, provides a resilient positioning effect for ensuring that the conductive arm is biased against the PCB through-hole during soldering. It would also be possible to provide a pair of conductive arms, for example with the same construction as the arms 44 of the embodiment of figures 1-6, whereby a further pair of arms in a plane substantially orthogonal thereto are the arms formed integrally with the housing. The housing resilient arms thus provide a secure location and retention of the connector on a PCB prior to soldering, whereas the conductive arm provides an electrical and mechanical connection after soldering. The embodiment of figures 7-9 also has the advantage of reducing solder dribble during the soldering process, because the four arms 44', 44'' occupy a large volume of the PCB hole 82. An additional advantage is the high retention force provided by the four mounting portions 56' , 56' ' . Referring to figures 10-14, a third embodiment is shown, which comprises the same or similar features to the connector of figures 1-6 except for the design of the boardlock. The numbering of identical or similar parts will be maintained and the description of parts given the same numbers in figure 10-14 as in figures 1-6, may be taken from the description above referring to the embodiment of figures 1-6. Only the major differences between this embodiment and the embodiment of figures 1-6 will be described hereinafter.

The boardlock 20' ' is integrally interconnected to the flange 26 of the shield member via a support section 30'' extending substantially orthogonally from the flange 26 arranged proximate the front end 32 of the connector 2''. A pair of boardlock arms 44 are bent at 90° through a corner 32 from the support sections 30''. As in the previously described embodiments, the boardlock arms 44 have enlargened portions with the elements 57, 58, 59, 60 as previously described for reception through a plated through-hole of a printed circuit board and resilient retention therein by engagement of the tapered surfaces 60 with a corner of the PCB hole. The assembly and bending operation of the boardlock arms 44 of the embodiment of figures 10-14 may be very similar to that already described for the embodiment of figures 1-6 as shown in the steps depicted in figures 2-6.

The embodiment of figures 10-14 differs from the embodiment of figure 1-6 mainly in that instead of providing resilient support members engaging the boardlock arms 44, the boardlock arms 44 are each integrally connected via respective support extensions or sections 30' ' to the flange 26 and a support member 50' ' is positioned between the boardlock support extensions 30''. The support member 50'' is shown in figures 12 and 13 as a rigid integral portion of the housing 4'' that also defines with outer housing portions 51 channels or cavities 70 that receive, guide and locate the boardlock support extension 30'' in the housing. The boardlock extensions 30' ' thus participate in the flexibility of the boardlock arms 44 by acting partially in bending within the plane defined by the sheet metal of the support extensions, and partially in torsion about an axis extending through the support extensions 30'' from the flange 26 to the corner 32. The boardlock 44, extending from the corner 32 to the end 57, also participates in the flexibility by some bending thereof in the plane defined by the boardlock arms 44.

As slight torsional displacement of the boardlock support extensions 30' ' translates into fairly large displacement of the free end 57 of the boardlock arms 44, the elastic displacement range of the boardlock arms is enhanced, particularly in combination with the bending mode of the boardlock support extensions 30'' and arms 44.

Advantageously the conductive boardlock portion may be made of a ductile material while ensuring reliable fixing prior to soldering. The retention function is reliably performed by the housing support members prior to soldering, in a compact and cost effective manner. The housing support members enhance the elastic displacement range of the boardlock by either providing resilient support or enhancing resilient displacement modes of the boardlock by encouraging torsion in addition to bending. Greater versatility is thus achieved in design of the electrical connection of the shield member to a PCB, and the connector is positioned with greater accuracy on the PCB.

Claims

1. A shielded connector (2) comprising an insulative housing (4), a shielding member (6) formed from a relatively ductile sheet metal, and one or more boardlocks (20,20'), each said boardlock having a plurality of mounting portions (56, 56' , 56' ' ) pluggable into a hole of a board or panel for electrical and mechanical connection of the shielding member and connector respectively to the board or panel, wherein each said boardlock has one or more support members (50, 50' , 50' ' ) for enhancing the elastic range of at least one of said mounting portions (56, 56' , 56' ' ) against an edge (80) of the circuit board hole (82), wherein at least one of the mounting portions (56,56'') is electrically conductive and electrically interconnected to the shielding member (6,6'') of the connector, and the support members (50,50') form part of the insulative housing (4) thereby providing enhanced resiliency of the boardlock (20, 20' , 20" ) .

2. The connector of claim 1 wherein the support member (50) comprises a support spring member (50) separate from but resiliently engaging the arms (44) of the boardlock, the arms (44) being stamped and formed from metal.

3. The connector of claim 2 wherein the spring member comprises a pair of spring beams (50) having engagement portions (62) at the ends of the spring beams (50) positioned between inner edges (54) of the boardlock arms (44) .

4. The connector of claim 2 or 3 wherein the boardlock mounting portions (56) are integrally connected to the shielding member (6) via a bend (46) formed by thin strips that are thinner than the boardlock arms (44) .

5. The connector of any one of claims 2-4 wherein the support spring member (50) has a locating surface (68) for abutment of the boardlock thereagainst during manufacturing, thereby locating the boardlock with respect to the housing (4) .

6. The connector of any one of the preceding claims wherein the support member (50) comprises a pair of cantilever beam spring arms attached integrally to the housing at an attachment end (64) and extending to free ends where engagement portions (62) are provided that engage the boardlock, the attachment end (64) extending from an intermediate wall (24) of the housing proximate a flange (26) of the shielding member (6), the shielding member having a deep drawn mating portion (22) extending substantially orthogonally from the flange (26) .

7. The connector of claim 1 wherein each boardlock has at least two mounting portions (56) which are each positioned proximate an end of a respective boardlock arm

(44) that are bent approximately orthogonally from respective support extensions (30'') that electrically interconnect a flange (26) of the shielding member (6'') to the mounting portion (56) , and wherein the support member (50'') is positioned between the at least two boardlock extensions (30'') such that the support extensions flex in torsion when the boardlock mounting portions (56) are biased towards each other.

8. The connector of any preceding claim wherein the shielding member (6) and boardlock (20) are integrally formed from sheet metal.

9. The connector of any one of the preceding claims wherein the boardlock mounting portions (56,56') are substantially planar and symmetrical about a vertical axis which corresponds to a direction of plugging of the boardlock into the board hole.

10. The connector of claim 1 wherein the mounting portions (44' ) that are biased by the support members

(50' ) are integrally formed therewith, the support members being resilient.

11. The connector of claim 10 wherein said resilient support members are in the form of cantilever beams extending from the housing to free ends (57' ) , the mounting portions (44') arranged proximate the free ends (57').

12. The connector of any one of the preceding claims wherein the shielding member has a mating portion (22) deep drawn from sheet metal .

13. The connector of anyone of the preceding claims wherein the support member (50, 50' , 50' ' ) is integrally moulded with the insulative housing (4) .