GB2198597A

GB2198597A - An electrical connector assembly and a housing therefor

Info

Publication number: GB2198597A
Application number: GB8725789A
Authority: GB
Inventors: William Wilson
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1986-12-10
Filing date: 1987-11-04
Publication date: 1988-06-15
Anticipated expiration: 2007-11-04
Also published as: JPS63160180A; GB8725789D0; GB2198597B; GB8629473D0

Abstract

An electrical connector assembly for connecting a predetermined conductor (C) of a flat flexible cable (FFC) to a predetermined conductor (C1) of a circuit board (PC), comprises an insulating housing (2) having a flat, cable receiving, surface (36) into which open cavities (8) receiving electrical terminal (80) crimped to respective conductors (C) of the cable (FFC) on the cable receiving surface (36), the cavities (8) extending normally thereof. The terminals have contact springs (92) projecting into a board receiving channel (24) in the housing (2), to make contact with the conductors (C1) of the board (PD) when it has been inserted into the channel (24). A cover (54) can be latched to the housing (2) to provide strain relief for the cable (FFC) and is adapted for floating connection to a chassis plate of an electrical apparatus. The housing (2) can be moulded without the use of side cores. <IMAGE>

Description

AN ELECTRICAL CONNECTOR ASSEMBLY AND A HOUSING THEREFOR This invention relates to an electrical connector assembly for connecting predetermined conductors of a flat flexible cable each to a predetermined conductor of a circuit board extending normally of the cable.

There is, in the electronics industry, for example, in computer construction, a demand for such connector assemblies, especially for those which are economical to manufacture. The invention is intended inter alia to provide such an assembly which comprises an insulating housing which can readily be moulded by the use of straight action mould cores, that is to say without side cores.

According to one aspect of the invention, an electrical connector assembly for connecting predetermined conductors of a flat flexible cable each to predetermined conductor of a circuit board extending normally of the cable, comprises an insulating housing -having a planar, cable receiving surface, the housing defining at least one row of elongate, terminal receiving cavities each opening into the cable receiving surface at one end and extending normally thereof, and a circuit board receiving channel also extending normally of the cable receiving surface and communicating with a side of each cavity in the vicinity of its opposite end, an electrical terminal in each cavity having a contact spring projecting into said channel for engaging a predetermined conductor of a circuit board inserted into the channel in the direction of the cable receiving surface, said terminal having a leg connected at one end to said contact spring and having its other end connected to a predetermined conductor of a flat flexible cable on said cable receiving surface.

According to another aspect of the invention, an insulating housing for an assembly according to the invention, is elongate and substantially T-shaped as seen in cross-section, two parallel rows of parallel, elongate, terminal receiving cavities each opening at one end into outer surface of the cross-arm of the T, and at the other end, into the free end of the vertical arm of the T, a central wall of the housing extending between said rows of cavities having at its end remote from said upper surface a board stop surface facing away therefrom and being disposed intermediate the ends of the cavities and providing the base of a board receiving channel opening into the free end of the vertical arm of the T, said central wall being formed with a reduced cross-section partition projecting towards said outer surface of the cross arm and a larger cross section portion defining said board stop surface and cooperating with said partition to define an abutment shoulder facing towards said outer surface, the wall of each cavity opposite to said central wall being formed, intermediate said abutment surface and said free end of said vertical arm, with a latching shoulder facing away from said abutment surface.

The housing may be provided with a latch-on cover, which cooperates with the housing to provide strain relief for the cable. The cover may be adapted to secure the connector assembly to the chassis of an electronic apparatus, but to allow the assembly to float to a limited extend relative to the chassis to allow for circuit board misalignment. The housing may alternatively be panel mounted.

For a better understanding of the invention and to show how it may be carried into effect, reference will now be made by way of example to the accompanying drawings in which: FIGURES 1 and 2 are a side view and a cross-sectional view, respectively, of an insulating housing for an electrical connector, according to a first embodiment of the invention, for connecting the conductors of a flat flexible cable, to respective conductors of a printed circuit board; FIGURE 3 is a greatly enlarged view of Figure 2, showing in broken lines, the position of contact springs in the housing, and also showing in fragmentary form, a circuit board about to be inserted into the housing; FIGURES 4 and 5 are a side view and an end view, respectively, of a cover which is latchable to the housing;; FIGURE 6 is a fragmentary cross-sectional view of the housing, illustrating how the cover, which is shown in broken lines, is latched to the housing; FIGURE 7 is a fragmentary isometric view of the cover taken from above; FIGURE 8 is an isometric view showing a plurality of electrical terminals which have been crimped to respective conductors of a flat, flexible cable, for assembly to the housing; FIGURE 9 is an isometric view of one of the terminals prior to its being crimped to a conductor of the cable; FIGURE 10 is a fragmentary end view of the cover showing it secured to a mounting plate of the chassis of an apparatus; FIGURE 11 is a fragmentary sectional view showing one of the terminals, and the cover, assembled to the housing; and FIGURE 12 is an isometric view of a housing according to a second embodiment of the invention, in association with a panel to which the housing is to be mounted.

As shown in Figures 1 to 3, the housing, which is elongate and is substantially T-shaped as seen in cross section, is generally referenced 2, and is made of an insulating material, comprises a central terminal receiving part 4 at either end of which is a circuit board guiding part 6. The part 4 is formed with two parallel rows of parallel terminal receiving cavities 8 (shown schematically in Figure 1) each cavity 8 of one row being opposite to a cavity 8 of the other row. Each cavity 8 has an upper portion 10 for receiving a leg of an electrical terminal, as explained below, an intermediate portion 12 for receiving a transition member of the terminal and a lower portion 14 for receiving a contact member of the terminal. The cavities 8 are each defined by an outer housing wall 16 and a central inner housing wall 18.

Each wall 16 provides in each cavity 8, a terminal latching shoulder 20 intermediate the cavity portions 12 and 14 and facing downwardly, as seen in Figures 2 and 3. The wall 18 provides in each cavity 8, a first terminal abutment shoulder 22 intermediate the cavity portions 10 and 12 and facing in the opposite direction to the shoulders 20, that is to say upwardly, and a similarly facing second terminal abutment shoulder 21. The part 4 of the housing 2 is formed with a circuit board receiving central channel 24 extending between, and opening into, one side of each of the cavity portions 14 of the two rows. The base of the channel 24 is provided by a board stop lower face 26 of the wall 18.

Each housing part 6 is formed with an internal chamfered surface 28 at its lower extremity, the surfaces 28 cooperating to provide a board guiding mouth leading into board guiding grooves 30 in the parts 6, each groove 30 communicating at its upper end, with the channel 24. There project from opposite sides of the walls 16, at the top of the housing portion 4, a pair of opposed flanges 32 extending longitudinally of the housing 2 and each being formed with a longitudinally extending cable strain relief groove 34 opening upwardly of the housing part 4 into a planar, cable receiving upper surface 36 of the housing 2. The surface 36 has pad receiving portions 37 proximate to the cavities 8. The grooves 34 are parallel to each other each being proximate to a longitudinal edge of the respective flange 32. The cavities 8 extend at right angles to the surface 36.

The wall 18 has a reduced cross section longitudinal partition 38 upstanding therefrom between the cavity portions 10 of the two rows of cavities 8 and terminating in a rounded top 39, there projecting laterally from the partition 38 fin-like transverse partitions 41 each projecting between the cavities 8 of the same row. Each housing part 6 is surmounted by a lid latching cavity 40 which is best seen in Figure 6 and which is defined by inner and outer side wall portions 42 and 44 respectively, of the board guide part 6 at that end of the housing 2. Each cavity 40 is also defined by a lower wall 46 formed with a latch arm receiving opening 48 having a chamfered latch arm deflecting surface 50, the wall 42 having a latching shoulder 52 facing in the same direction as the shoulders 20.

The flanges 32 provide the cross-arm of the T-cross section housing 2.

A cover 54 for the housing 2 comprises, as shown in Figures 4, 5 and 7, an elongate body 56 made of an insulating material, and having an upper surface 58 and a lower surface 60. There project from the lower surface 60, a pair of opposed cable strain relief ribs 62, each proximate to a lateral face 64 of the body 56 and each being for reception in a respective one of the grooves 34 of the housing 2. From each end of the surface 60, there projects a pair of latch arms 66 (which are not shown in Figure 7), and each of which has an inwardly directed latching hook 68. There is formed in the surface 58, a longitudinally extending cavity 70 which lies substantially midway between the end faces 72 of the body 56 and which is bridged by a resilient strip 74 of the material of the body 56, as best seen in Figure 7.The strip 74 is surmounted by a stud 76 which is resiliently depressible by virtue of the resilience of the strip 74, as indicated by the arrow A in Figure 7. At each end of the cavity 70 is an undercut mounting lug 78 upstanding from the surface 58 and defining opposed grooves 77 extending longitudinally of the body 56 and having upper walls 79.

As shown in Figures 8 and 9, identical electrical terminals 80, for assembly to the housing 2, each comprise a contact member 82, which is formed integrally with an intermediate, annular, transition member 84, from which extends a leg 86, terminating in a crimping ferrule 88. The contact member 82 has formed integrally therewith, a forward ring 90 beneath which is latched, one end of a contact spring 92 which is bowed outwardly of the member 82 and extends through the portion 84. The spring 92 terminates in a hooked abutment 94 projecting from that end of the member 84 which is remote from the member 82. On its side opposite to that from which the contact spring 92 projects, the contact member 82 is formed with a resilient latching tongue 96 which projects obliquely rearwardly of the terminal 80.The ferrule 88, which is substantially U-shaped, has on each edge thereof a pair of tines 98, only two of which are shown.

Prior to assembly to the housing 2, the terminals 80 are mounted on a length of flat flexible cable FFC (Figure 8) having parallel conductors C. To this end, a strip of the terminals 80 is fed to an application machine (not shown) which bends the legs 86 to the position in which they are shown in Figures 8 and 9, inserts the two pairs of tines 98 of each ferrule 88 through the insulation of the cable FFC so as to embrace an individual conductor C thereof, and crimps the tines 98 about the conductor C. An adhesive pad P is then placed over each ferrule 88 as shown in Figure 8.Following this operation, each terminal 80 is inserted in the direction of the arrow B in Figure 3, with its ring 90 leading, into a respective cavity 8 of the housing 2, guided by the partitions 38 and 41, so that the contact member 82 of each terminal 80 lies in a cavity portion 14 of one row with its contact spring 92 facing the contact spring 92 of an opposite terminal 80 in the other row, and projecting arcuately into the channel 24, as indicated in broken lines in Figure 3.When the terminals 80 have been inserted into the cavities 8, the cable FFC lies on the cable receiving surface 36 of the housing 2, with the pads P lying the portions 37 of the surface 36, as shown in Figure 11, the legs 86 of the terminals 80 being received in the cavity portions 10 between the partitions 41, the transition members 84 being lodged in the cavity portions 12, with each hook 94 thereof abutting one of the shoulders 22. The lower end of each member 84 abuts a respective shoulder 21, and the members 82 of the terminals 80 are each received in one of the cavity portions 14, with the end of its latching tongue 96 overlying the shoulder 20 in the cavity portion 14. In the inserted position of the terminals 80, the cable FFC extends across the grooves 34 in the cable receiving surface 36.

The cover 54 is now assembled to the electrical connector provided by the housing 2 and the terminals 80. Each pair of latch arms 66 is inserted into a cavity 40, so that the hook 68 of the latch arm enters the respective opening 48 so that the latch arm 66 is cammed by the respective cam surface 50, to latch its hook 68 under the respective shoulder 52 in the opening 47. In the assembled position of the cover 54 each rib 62 of the cover 54 pushes the cable FFC down into the respective groove 34 as shown in Figure 11, thereby securing the cable FFC against strain so as to protect the crimped connections to the cable conductors C.

Terminals 80 on a plurality of strips of cable FFC may be assembled to the housing 2 in the manner described above, prior to the assembly of the cover 54 thereto.

In use, the connector assembly comprising the terminals 80, the housing 2, and the cover 54, may be secured to a chassis, for example, of an electronic apparatus, by inserting the lugs 78 on the cover 54 into holes (not shown) communicating with slots 100 (Figure 10), in a mounting plate 102 on the chassis, to depress the stud 76 against the action of the strip 74, whereby the stud 76 presses the plate 102 into firm engagement with the under sides of the walls 79 of the grooves 77 of the lugs 78 (Figure 10), as the latter are slid along the slots 100 to produce a bayonet joint between the mounting plate and the connector assembly. The stud 76 finally enters an oversized hole 103, between the slots 100, in the plate 102 and accordingly resiles into the hole 103.

With the connector assembly so mounted, a circuit board PC may be inserted, in the direction of the arrow D in Figure 3, by way of the grooves 24 in the housing parts 6 and guided by the mouth surfaces 28, into the channel 24, so that each contact spring 92 engages the proximate printed conductor C1 on the circuit board PC, electrically to connect the conductor C1 to a respective conductor C of the cable FFC.

As will be apparent from Figure 10 there will be some play between the plate 102 and the lower surfaces of the walls 79 of the grooves 77 so that the connector assembly will float so as to allow for circuit board misalignment.

As the grooves 30 and 34, the cavities 8 and the channel 24 all extend in the same direction, the housing 2 can be moulded by means of straight action core pins, without the provision of side cores.

According to the embodiment of Figure 12, in which parts which are similar to those described above, bear the same reference numerals with the addition of a prime symbol, the housing 2' is panel mounted, instead of the cover being mounted to a chassis. To this end, the part 6' is formed on each side thereof with a pair of latching projections 110 for engaging the lower surface of a panel 112 into a hole 114 in which, the part 6' is to be inserted, the opposite lower faces 116 of the part 4' each being formed with an elongate resilient arm 118 having a depending end portion 120 for engaging the upper surface of the panel 112, and with an abutment 122 also for engaging the upper side of the panel 112.

The surface 36' has thereon, in place of the grooves 34, parallel ribs 124 which extend along its longitudinal boundaries, lengthwise of the housing 2', and which cooperate with ribs, similar to the ribs 62, on a cover (not shown) to trap the cable, when the cover is in place on the housing 2', the ribs on the cover urging the cable against the ribs 124. The ends of the part 6' are provided with transverse bars 126 for engagement by latch arms on the cover.

Claims

CLAIMS:

1. An electrical connector assembly for connecting predetermined conductors of a flat flexible cable each to predetermined conductor of a circuit board extending normally of the cable, the connector comprising an insulating housing having a planar, cable receiving surface, the housing defining at least one row of elongate, terminal receiving cavities each opening into the cable receiving surface at one end and extending normally thereof, and a circuit board receiving channel also extending normally of the cable receiving surface and communicating with a side of each cavity in the vicinity of its opposite end, an electrical terminal in each cavity having a contact spring projecting into said channel for engaging a predetermined conductor of a circuit board inserted into the channel in the direction of the cable receiving surface, said terminal having a leg connected at one end to said contact spring and having its other end connected to a predetermined conductor of a flat flexible cable on said cable receiving surface.

2. An assembly as claimed in claim 1, further comprising a cover releasably latched to said housing and having a rib on each side of, and extending longitudinally of said row of cavities.

3. An assembly as claimed in claim 2, in which each rib protrudes into a groove formed in said cable receiving surface and also extends longitudinally of said row, the cable being frictionally engaged between each rib and the internal surface of each groove.

4. An assembly as claimed in claim 2, in which each rib urges the cable against a corresponding rib bounding said cable receiving surface and extending longitudinally thereof.

5. An assembly as claimed in claim 2, 3 or 4 in which one side of said cover engages said cable, the opposite side of said cover having a pair of spaced undercut lugs projecting therefrom for reception in a slot in a mounting plate for the connector assembly, a resilient member projecting from said opposite side of the cover for reception in a hole in said mounting plate.

6. An assembly as claimed in claim 5, in which said resilient member is in the form of a stud carried by a strip of the cover material, spanning an opening in said opposite side of said cover.

7. An assembly as claimed in any one of the preceding claims, in which said housing defines, in each cavity, an abutment shoulder on said one side of the cavity and facing towards said cable receiving surface, and a latching shoulder on the opposite side of said cable receiving surface, the terminal in said cavity having an abutment engaged with said shoulder to prevent movement of the terminal away from said cable receiving surface and a latching tongue engaged with said latching shoulder to restrain movement of said terminal towards said cable receiving surface, said abutment shoulder being nearer to said cable than said latching shoulder.

8. An assembly as claimed in any one of the preceding claims, in which the housing, which is elongate, comprises a central terminal receiving part through which the terminal receiving cavities extend and a board guiding portion at each end of said central portion and projecting therefrom in a direction away from said cable receiving surface, each board guiding portion having a board guiding groove communicating with said channel.

9. An insulating housing for an assembly as claimed in claim 1, the housing being elongate and being substantially T-shaped as seen in cross-section, two parallel rows of parallel, elongate, terminal receiving cavities each opening at one end into the outer surface of the cross-arm of the T, and at the other end, into the free end of the vertical arm of the T, a central wall of the housing extending between said rows of cavities having at its end remote from said upper surface a board stop surface facing away therefrom and being disposed intermediate the ends of the cavities and providing the base of a board receiving channel opening into the free end of the vertical arm of the T, said central wall being formed with a reduced cross section partition projecting towards said outer surface of the cross arm and a larger cross-section portion defining said board stop surface and cooperating with said partition to define an abutment shoulder facing towards said outer surface, the wall of each cavity opposite to said central wall being formed, intermediate said abutment surface and said free end of said vertical arm, with a latching shoulder facing away from said abutment shoulder.

10. A housing as claimed in claim 9, in which said central wall is formed with a further abutment shoulder intermediate the first mentioned abutment shoulder and said latching shoulder.

11. A housing as claimed in claim 9 or 10, which is formed at each end thereof with a cavity for receiving a latch arm on a cover for said outer surface of the cross arm, the base of the cavity having an opening therein for receiving a hooked end of said latch arm, the base being formed with a cam surface in each opening on one side thereof, and on the opposite side of said opening, with a latching shoulder for said hooked end.

12. A housing as claimed in claim 8, in which the vertical arm of the T is formed with a latching projection for engaging the underside of a panel, the cross-arm of the T being formed with a resilient arm extending longitudinally of the housing, for engaging the other side of the panel.

13. An electrical connector assembly for connecting predetermined conductors of a flat flexible cable each to a predetermined conductor of a printed circuit board, substantially as hereinbefore described with reference to the accompanying drawings.

14. An insulating housing for an assembly as claimed in claim 1, substantially as hereinbefore described with reference to the accompanying drawings.