DE3789947T2 - Modular distribution connector for circuit board. - Google Patents

Description

The invention relates to a modular collective connector for a printed circuit board and a connector system.

There is an increasing need to provide automated process control in various manufacturing units (for example, a wire E.D.M. plant). However, in the interest of minimizing capital investment, the user desires to initially install a relatively inexpensive unit that performs only the basic control functions and to have the ability to expand if justified at a later date.

To allow for such future expansion, the user is typically provided with at least one daughter board, which is connected to connectors on a mother or bus board, to which several further connectors are attached to accommodate additional daughter boards if required to increase the capacity of the system. However, the provision of additional connectors increases the initial capital outlay, while the fixed design of additional connectors may also result in limitations on the connections possible for the additional printed circuit boards, which may undesirably limit the types that can be used.

US Patent 4,322,120 discloses an electrical interconnect system for distributing power and data signals to and from insulating substrates carrying conductor traces and comprising a plurality of insulating housing means each having opposite parallel ends and a printed circuit board receiving slot on one surface disposed between and parallel to the ends. The housing means also includes printed circuit board receiving contacts disposed in the printed circuit board receiving slots and has collecting means extending between the opposite ends.

According to the invention, the electrical connection system is characterized in that that the collecting means has resilient contact regions formed at each of its ends which are arranged for abutting contact with complementary resilient contact regions of a similar insulating housing.

According to one aspect of the present invention there is an electrical connector system as defined in claim 1, and according to another aspect of the present invention there is an electrical connector as defined in claim 5.

Thus, additional connector modules only need to be added when needed, avoiding the initial capital outlay required by previous proposals. Furthermore, selectively separating the bridge area before or after inserting the contact elements into the housing allows different combinations of connections both to the circuit board and to the adjacent modules and to the circuit board connected in them.

In one version of the connector module, the housing has contact element receiving channels, and the contact elements have metal stampings formed with first and second contact areas at respective opposite ends. In a preferred example, a pin area extends from the bridge at a midpoint and out of the housing to allow a stud or wire connection to a similar pin area in an adjacent slot of the same module, the bridge being able to be severed at either side of the pin area to isolate either the first or second contact area from both the pin area and the second or first contact areas, respectively.

The provision of the pin area makes it possible for a further combination of connections to the circuit board tracks to be achieved by short-circuiting adjacent contact elements of the same connector module.

It is further preferred that the further board engaging contact spring means comprises two contact springs extending from opposite ends of the separable bridge portion proximate the first and second contact portions and defining an edge connector therebetween for engaging conductor tracks on opposite sides of a circuit board.

It is also preferred that one of the contact springs engaging another plate is connected to the bridge near the second contact spring via a separable region and that a tool receiving recess extends along the housing, transverse to which recess the separable region extends.

It can be seen that the selective separation of the bridge on one side of the pin area in combination with the possibility of separating the separable area of the second contact spring on both sides and the selective short-circuiting with adjacent contact elements creates the possibility that a large number of variations of different connections can be achieved.

A second embodiment of the connector collection system includes a flexible substrate attached to the housing; the substrate has a plurality of conductive traces, the flexible substrate and at least a portion of the conductive traces extending to the longitudinal edges thereof where the longitudinal edges have interconnection means for mechanical interconnection to a similar housing. The similar housing has a similar substrate, the substrate similarly overlapping the mating longitudinal edge such that the interconnection between the two housings mechanically locks them together and electrically interconnects them at at least a portion of the edge traces of the printed circuit board.

In the preferred version of the second embodiment, at least one of the longitudinal edges has an elastomeric insert disposed beneath the substrate and the electrical traces along the end edges thereof are resiliently biased against respective traces on the interconnectable printed circuit board. It is further preferred that each longitudinal edge has a recessed region with an elastomeric insert disposed within each recess, the inserts being deformable to the extent of abutment against the interconnectable end edges.

The modules of each embodiment can be assembled together by means of a mounting rail and/or have longitudinal edges equipped with notches or complementary joining areas for mutual fastening.

An exemplary embodiment of the invention will now be described with reference to the accompanying drawings, in which

Fig. 1 is a partial perspective view, partly in section, of two assembled connector modules;

Fig. 2 is a schematic perspective view of adjacent contact elements aligned with conductor tracks of a printed circuit board;

Fig. 3 is a view similar to Fig. 2, schematically showing various connections to the circuit board that can be achieved by selectively separating and shorting adjacent contact elements;

Fig. 4 is a perspective view of another embodiment of the modular collection system showing two modular housings mechanically interconnected with a printed circuit board shown floating for receipt within slots that form an entry for the edge guide of the printed circuit board.

Fig. 5 is a cross-sectional view taken substantially along line 5-5 of Fig. 4 showing a second housing assembly floating for receipt in a first housing

Fig. 6 is a view showing the continuous wrap of flexible substrate forming the subassemblies of the modular connector floating for receipt over the elastomeric inserts;

Fig. 7 the flexible substrate after it has been heat-fused or adhesively bonded to the elastomeric inserts;

Fig. 8 is a perspective view of the assembled elastomeric connector subassembly.

As shown particularly in Fig. 1, each connector module 11 of the first embodiment has a housing 12 which is integrally molded from a suitably rigid plastic and carries a series of identical, flat, stamped metal contact elements 13.

Each housing module 12 is formed as a block which is rectangular in plan and which in practice is elongated in the direction of extension Z of a joining edge 15 of a printed circuit board. First and second opposite longitudinal edges 16 and 17 of the block are each provided with complementary male and female dovetail joints 19 and 20 for fastening adjacent Modules 11 are formed in mutual edge relationship and a series of contact element receiving channels 21 opening onto a board receiving surface 22 extends from edge to edge such that upon mutual attachment of adjacent modules 11, corresponding channels 21 are brought into alignment of their ends. Each channel 21 is crossed by a relatively deep card receiving slot 23 and by a relatively shallow tool access recess 24 which extend along the board receiving surface 22 parallel to one another and adjacent but successively spaced from the first longitudinal edge 16 and the opening to the surface 22. The opposing surface 26 of the housing module 12 is formed at a generally central location with a similarly oriented, channel-shaped cross-sectional connector receiving recess 27. A bottom plate 28 of each channel 21 is discontinuous, with parallel wall portions defining a contact element anchoring base 31, 32 on each longitudinal side of the connector receiving recess 27 and a contact pin receiving opening 33 central to the recess. On each side of the recess, the channels define contact spring cavities 34, 35, respectively, of increased depth, located near the respective opposite longitudinal edges 16 and 17 of the housing, but spaced therefrom by contact spring retaining end wall portions 37, 38, respectively, extending from the bottom wall portion toward the connector receiving surface 22, allowing contact of the aligned contact elements of adjacent modules when assembled.

Each contact element 13 has substantially identical first and second oppositely oriented cantilever spring contacts 41 and 42 at respective ends, each with first and second perpendicularly disposed spring arm elements 42 and 44 extending from rigidly resilient vertical shafts 45 and 49, respectively, connected to first and second anchoring posts 51 and 52. A generally right-angled spring cantilever 53 is connected to the first post 51 to extend towards the first spring contact and has a reversely inclined first printed circuit board contact region 54 at a free end arranged in oppositely spaced relation to a second printed circuit board contact region 55 extending from a cantilever spring element 56 which is connected by a detachable region 57 to the second anchoring post 52 and which merges into a relatively solid stabilizing body region 58. The first and second anchoring regions are connected by a detachable bridge 61, with a central A contact pin 62 extends from this location.

It should be noted that the cantilever elements may have a progressively decreasing width as they extend towards the free contact ends to ensure a desirably progressive increase in spring stiffness with increasing deflection.

In assembling the module, the contact elements 13 are either fully inserted into respective channels 21 as shown in Fig. 1 or after the bridge 21 has been selectively severed on one side of the contact pin 62 to provide multiple interconnections to the traces on the printed circuit board 15 as described below. Furthermore, the region 57 can also be severed after being received in the housing to remove the second printed circuit board contact region 55 if a connection is required on only one side of the printed circuit board 15.

Once inserted into these channels, the first and second contact springs 41 and 42, respectively, are positioned in the cavities 34 and 35 by means of the anchoring posts which are frictionally seated in the sleeves so that the first contact region 56 projects beyond the first edge of the housing and the first and second printed circuit board contact regions 54 and 55 project into the printed circuit board receiving slots 23 for electrical connection to traces on respective opposite sides of a printed circuit board inserted into the slot. The detachable region 57 extends across the tool receiving recess 24.

Some of the possible interconnections will now be described with reference to the drawings, in which P1 and P2 denote adjacent traces on the same face of a printed circuit board, P3 and P4 denote traces on the opposite face which are aligned with traces P1 and P2 respectively.

As shown in Fig. 2, the entire contact element has the bridges 61, 61' un-separated, resulting in the contact areas 54 and 55 connecting both P1 and P2 to the two spring contacts 41 and 42 at each end of the contact element and therefore to the aligned contact elements of any adjacent modules assembled therewith. The connection of the pins 62 and 62' by means of a shunt, as shown in phantom in Fig. 3, connects all tracks P1-P4 to both adjacent contact elements 13, 13'.

According to the phantom representation in Fig. 3, the bridge 61 of the contact element 11 can be separated to the left of the pin 62, which isolates the contact springs 41 and 42 and results in P1 being connected only to the contact spring 42, while P2 is only connected to the contact spring 41. When the pins 62 and 62' are short-circuited as shown in the phantom representation, P1 is also connected to the two contact springs 41' and 42' of the contact element 13' and thus to both P2 and P4 of the circuit board.

Fig. 3 shows that the bridge 61 of the contact element 13 can be separated to the right of the pin 62, thereby creating the same connections as indicated above. However, when the pins 62 and 62' are short-circuited, P1 is connected only to 42. P2 is connected to 41, 41' and 42', and P3 is connected to both contact springs 41' and 42' of the contact element 13' and thus to both P2 and P4.

As observed by careful inspection of Fig. 3, many combinations of interconnections can be created by separating the bridges 61 and 61' and additionally by separating arm portions 57 or 57' to remove the contact portions 55 or 55', thereby isolating P1 and P2 after the contact elements have been placed in the housing module.

In an alternative example (not shown), the pin 62 is replaced by a conventional wire receiving slot into which a wire can be pushed to make a connection therewith.

Referring first to Fig. 4, the second embodiment of the modular connector system has a modular connector assembly, generally designated 102, which has an insulating housing, for example 104, with end walls 106 and 108. Between the end walls 106 and 108 extends a recess, for example 110, with side walls 112 and a bottom 114 (Fig. 5). The side walls 106 and 108 further have dovetail extensions 116 and dovetail slots 118 for mechanically connecting two identical housing parts. Fig. 4 also shows that a slot, for example 120, is provided on the underside of the insulating housing 104, which has a groove, for example 122, for receiving side edges 172 of the locking rail 170. It should be noted that when the two housings are locked together with the dovetail extensions within the dovetail slots and the locking bar 170 is in position within the slot 120, the modular connectors are firmly connected to one another since the modular connector housings are locked together along two different axes.

Referring to Fig. 6, a connector subassembly is formed from a continuous flexible substrate, e.g., 182, which is unwound from a wrap (e.g., 174). The flexible substrate 182 has electrical traces generally designated 184 in Fig. 6. The continuous flexible substrate is unwound from the wrap 174 and placed over a plurality of elastomeric inserts, e.g., 150. Note, referring to Fig. 6, that the elastomeric inserts have a planar surface, e.g., 152, and two angled surfaces, e.g., 154, facing away from the planar surface 152. Once the flexible substrate is properly aligned over the elastomeric inserts, the flexible substrate 182 may be heat fused or adhesively secured to the elastomeric inserts, whereby the flexible substrate 182 conforms to the shape of the planar surface and angled surfaces 154.

When the flexible substrate 182 is firmly secured to the elastomeric inserts, the elastomeric inserts and the flexible substrate may be adhesively secured to the insulating block shown at 132 in Fig. 8. It should be noted that the elastomeric inserts 150 are suitably spaced to allow the flexible substrate to conform to the configuration shown in Fig. 8. It is desirable that the flexible substrate lie along the top of the planar surface of the insulating block 132, fall into a recess, for example 140, with the elastomeric inserts adhesively secured to the side walls 142, 144 of the recess 140 and the planar surfaces of the recess facing opposite the flexible substrate which conforms between the two inserts along the bottom 146 of the recess 140. It is also noted that an insert 150 and a flexible substrate partially overlapping the insert 150 are secured to an end wall, for example 136, of the housing block 132, while a second elastomeric insert 150 having a second overlapping end of the flexible substrate is secured to an end wall, for example 138. It is also noted that collection areas, for example 160 and 162, are located between the opposing end walls Once the flexible substrate has been secured to the insulating block, the insulating block 132 is insertable within the recess 110 and adhesively secured therein. It should be noted that the block 132 and the housing 104 may be integrally formed into a single unitary component. As shown in Figs. 4 and 5, the elastomeric inserts secured to the end walls 136 and 138 of the insulating block 132 are slightly recessed within the end walls 106 and 108 of the housing 104 with the planar surfaces 152 of the elastomeric inserts extending beyond the end walls 106 and 108. In this manner, as shown in Fig. 5, a first insulating housing, e.g., 102, is aligned with an identical connector housing 2' with the elastomeric inserts in resiliently biased electrical interconnection along end walls 106 and 108. Furthermore, the two inserts 150 adhesively secured within recess 140 form an electrical connector for interconnecting a printed circuit board, e.g., 200, having edge guides 202 (Fig. 4) with conductor tracks, e.g., 204, extending toward edge guides 202. It can be seen from Fig. 6 that flexible substrate 182 includes a programming feature that can permit electrical interconnection between two tracks on opposite sides of a printed circuit board when the two tracks are not aligned and the two tracks skip at least one intermediate track. In particular, the flexible substrate has a track, for example 186, which is aligned with track 190, although tracks 186 and 190 are not electrically connected to each other, but instead are not electrically connected to each other in that region of the flexible substrate which falls within recess 140. Instead, track 186 is connected to track 188, skipping track 192. Track 194 and track 192 are still in line with tracks 188 and 196. When the flexible substrate 182 conforms to the elastomeric inserts 150, for example as shown in Fig. 7, and is placed within a recess 140 as shown in Fig. 8, the skipping regions are pushed out from under the inserts 150 and cannot be contacted by the printed circuit board during board insertion. In this manner, traces 194 and 196 may still be used as electrical interconnects to associated traces on a first side of the printed circuit board, and traces 190 and 192 may be used for electrical interconnection on opposite sides of the printed circuit board. Traces 186 and 188 skip traces 192 and 194 to electrically connect associated traces on opposite sides of the printed circuit board that are not aligned.

Referring to Figs. 1 and 4, it should be noted that the modular connectors, for example 11 and 102, are expandable to any extent. The modular connectors, for example 11 and 102, are advantageous in a system where several options are required, the options not always being supplied by the manufacturer as standard equipment. The present invention is then used as a modular energy collection system and as a modular printed circuit board. Options can be added to the system by the manufacturer or by the end user by simply extending the electrical connection between two modular connectors and inserting the logic for the options via printed circuit boards 15 and 200.

Claims (11)

1. An electrical interconnect system for distributing power and data signals to and from insulating substrates (15, 200) carrying conductive traces (P1-4, 184) thereon, the electrical interconnect system comprising a plurality of insulating housings (12, 104), each having opposing, parallel ends (16, 17, 106, 108) and a circuit board receiving slot (23, 140) on a surface (22) disposed between and parallel to the ends (16, 17, 106, 108), printed circuit board receiving contacts (13, 184) disposed in the printed circuit board receiving slot (23, 140) having collecting means (43, 49, 160, 162) disposed between the opposing Ends (16, 17, 106, 108), the collecting means (43, 49, 160, 162) being formed at each of the ends (16, 17, 106, 108) with compliant contact areas (41, 42, 160, 162) arranged for face-to-face contact with complementary, compliant contact areas of a similar insulating housing when the housings are arranged in end-to-end abutting relationship, the compliant contact areas (41, 42, 160, 162) extending beyond the opposite ends (16, 17, 106, 108), and for slidably contacting the complementary, compliant contact areas (41, 42, 160, 162) are profiled when the housings (12, 104) are moved relative to one another into an end-abutting relationship, and wherein the opposing ends (16, 17, 106, 108) of the insulating housings (12, 104) have latching structures (19, 20, 116, 118) that are complementary to latching structures on the opposing ends of the similar insulating housings, characterized in that the latching structures (19, 20, 116, 118) are slidably engageable with the complementary latching structures in a direction parallel to the plate receiving slots (23, 140) to guide the housings (12, 104) into an end-abutting relationship in the parallel direction, wherein the resilient contact areas (41, 42, 160, 162) are detachable from the latching structures (19, 20, 116, 118) and can only be brought into engagement with the complementary, flexible contact areas when the housings (12, 104) have been guided into an end-side alignment. 2. Electrical connection system according to claim 1, characterized in that the receiving contacts (13, 184) have means for selectively joining the receiving contacts (13, 184) of the same insulating block. 3. Electrical connection system according to claim 1 or 2, characterized in that the receiving contacts (13) are punched from flat metal plates. 4. Electrical connection system according to claim 1 or 2, characterized in that the receiving contacts (184) have conductor tracks (184) arranged on flexible substrates (182), the substrates (182) lying over a compliant, elastomeric material (150) and the substrates (142) and the elastomeric material (150) are arranged on the insulating housings (104) in a profile to form opposing contact surfaces. 5. Electrical connector with an insulating housing means in the form of an insulating module (12, 104) with a circuit board receiving slot (23, 140) provided therein and a plurality of receiving contacts (13, 184) arranged in the circuit board receiving slot (23, 140) and with a series of collecting means (43, 49, 160, 162) extending between the opposite, parallel ends (16, 17, 106, 108) of the module (12, 104), wherein the collection means (43, 49, 160, 162) are defined such that at least one is compliant and at least one is arranged to project beyond one of the opposite parallel ends (16, 17, 106, 108), and wherein the opposite parallel ends (16, 17, 106, 108) are adapted to be assembled in edge-to-edge relationship with another similar connector module (12, 104) to bring complementary conductive collection areas into electrical contact with selectively interconnected receptacle contacts on similar modules, characterized in that the collection means (43, 49, 160, 162) intersect the circuit board receiving slot (23, 140) and selectively communicate with the receptacle contacts (13, 184). 6. Electrical connector according to claim 5, characterized in that the receiving contacts (13, 184) have first and second contact elements (54, 55, 192, 194) which are connected by a possible bridge region (61), whereby if the latter is omitted, one collecting region (43, 49, 160, 162) is insulated from the other. 7. Electrical connector according to claim 6, characterized in that the housing means (12) has contact element receiving channels (21) extending between the opposing parallel ends (16, 17, 106, 108) and the receiving contacts (13), and that the collecting means (43, 49) have metal stampings formed with first and second contact areas (41, 42) at respective opposing ends. 8. Electrical connector according to claim 7, characterized in that a pin portion (62) extends from the bridge portion (61) at a middle position and out of the housing means (12) to enable a lug or wire connection to a similar pin portion of a contact element in an adjacent slot of the same module. 9. Electrical connector according to claim 7, characterized in that the receiving contacts (186-196) and the collecting means (160, 162) are formed by conductor traces (184) arranged on a flexible substrate (182), the flexible substrate (182) being attached to the housing means (104), the conductor traces (184) extending between the opposite, parallel ends (16, 17, 106, 108) and extending into the circuit board receiving slot (140) for electrical interconnection to the traces (204) of the printed circuit board. 10. Electrical connector according to claim 9, characterized in that the elastomeric inserts (250) are arranged beyond the flexible substrate (182) in the vicinity of the circuit board receiving slot (140) on opposite, parallel surfaces of the slot (140) and beyond the flexible substrate (182) at the opposite parallel ends (16, 17, 106, 108). 11. Electrical connector according to claim 5, characterized in that the insulating housing means (12) has a tool receiving slot (24) which is spaced from and runs parallel to the circuit board receiving slot (23) and transversely to which extend the collecting means (43, 49) which are exposed for selective separation by means of a tool insertable into the tool slot (23).