US 3569790 A
Description (OCR text may contain errors)
United States Patent  PLUG-IN TYPE CONNECTOR HAVING SHORT SIGNAL PATH 6 Claims, 4 Drawing Figs.
 U.S.Cl 317/101, 339/17, 339/256, 339/273  Int. Cl. H051: 1/12  Field ofSearch 317/101 (C), 101 (CM), 101 (D), 101 (DH); 339/17, 18,
IBM Technical Disclosure Bulletin Vol. 6, No. 1, June, 1963 Page 36 Primary Examiner-Marvin A. Champion Assistant Examiner-Patrick A. Clifford Attorney-Hill, Sherman, Meroni, Gross & Simpson ABSTRACT: A plug-in type connector for use in electronic systems with high component density and, in particular,
systems involving impulse processing in the subnanosecond range, in which the conductive path across the connector structure is reduced to a minimum, employing contacting ele- 273 ments which comprise a contact pin and a hollow resilient cooperable contact element, such as a coiled spring, con-  References C'ted structed to resiliently receive the free end of the pin, with the UNlTED STATES PATENTS latter being formed to expand said cooperable element and 1,946,889 2/ 1934 Wessel 339/ l 8(C) conductively engage the same.
1 I B I I 1 Ba 1 1 7a 7' I 7 9a I i s N i-i PATENICTED m 9197;
saw 10F 2 PRIOR ART R K O.l TN NE Ed V NZ N A R F I $.44 v BY M ATTORNEYS PATENTEDHAR SIS?! 3,559,790
' SHEET 2 OF 2 I Fig.3
. I g -e v I 88 INVENTOR FRANZ JENIK ATTORNEYS PLUG-IN TYPE CONNECTOR HAVING SHORT SIGNAL PATII BACKGROUND OF THE INVENTION The continually increasing use of fast-acting integrated switching circuits in the form of micromodules in connection with the construction of large electronic systems, particularly data processing installations, has resulted, not only a in a reduction of space requirements, but has also made possible an increase in switching speeds as a result of the shorter line length required. A further improvement in switching characteristics can be achieved by the utilization of a construction in which the signal lines are in the form of strip lines with a predetermined wave resistance. As a result, the trend has been predominantly toward the utilization of micromodules assembled on a platelike multilayered carrier of insulative material, in which on each layer there are arranged suitably formed conductor paths, constructed, for example, in accordance with printed circuit techniques. Obviously, the shortest signal lines would be obtained with a predetermined wave resistance, selectable within limits, and it will be appreciated that the highest switchingv speed would be achieved if all the micromodules or units of a system were accommodated in a single large constructional assembly. This, however, is contradictory to the requirement that an installation be composed of small, easily separable subassemblies to enable and facilitate fast and simple maintenance operations.
It is a known practice to combine a number of microniodules which, individually, may consist, for example, of several gate and/or sweep circuits employing integrated circuit techniques, in the form of flat construction units which are constructed for plug-in assembly. Such a construction subassembly may, for example, consist of a multilayered conductor plate, on which the integrated modules are soldered in place It is adapted to be connected by means of plug-in contacts with a wiring or circuit plate which is specifically designed to provide signal lines with defined wave resistances,
as well as achieve a high effective conductor density, which plate, likewise, is multilayered.
A common type of plug-in connection (described in Elektronik, 1966, No. 10, pages 31 l3 15) is illustrated in FIG. 1 of the drawings. As subsequently discussed in detail, the connector illustrated is of generally elongated construction, utilizing an elongated pin and cooperable elongated contact spring, as well as an elongated supporting structure therefor, resulting in a long conductive path across the connector, that is not compatible with maximum switching speeds.
The present invention, therefore, has among its objects the production of a connector structure of the plug-in type in which the conductive path between the circuits to be connected is of a minimum length, at the same time enabling the realization of a high component density.
Another object of the invention is the production of such a connector structure which is extremely simple in construction, having a minimum number of parts, and which will provide a highly efficient conductive connection.
A further object of the invention isthe production of such a plug-in type of connector which may be fabricated, not only with small transverse dimensions, but also with very small longitudinal dimensions.
BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the invention will be readily apparent from the following description of a preferred embodiment thereof, taken in conjunction with the accompanying drawings, in which like reference characters indicate like or corresponding parts, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure, and in which:
FIG. I is a longitudinal sectional view of a known type of plug-in connector construction;
FIG. 2 is a transverse section through a construction subassembly illustrating the male portion of the plug-in connector structure in simplified form; I
FIG. 3 is an enlarged FIG. of a portion of the structure illustrated in FIG. 2, illustrating additional details of the connector structure and its cooperation with the female portion of the connector; and
FIG. 4 is a transverse sectional view similar to FIG. 3 of a modified form of springcontact element.
DESCRIPTION OF PREFERRED EMBODIMENT As briefly mentioned previously, the known plug-in connector illustrated in FIG. 1 is of elongated construction, in which the flat construction subassemblies (not illustrated) are provided with a plurality of conductor pins, such as the pin 1 which, for example, may have a transverse width greater than the thickness thereof illustrated in FIG. 1 and, for example, may be electrolytically reinforced or thickened. The pin 1 is adapted to be contacted at point A by a contact spring 2 mounted in a body or base member 3 which, in turn, is secured to a multilayered wiring or circuit plate 4, the contact spring being suitably connected as, for example, by soldering at point B with a conductor path of the multilayered wiring plate 4.
As the contact spring 2 must engage the pin 1 at point A with a sufficiently high contact pressure, which will not appreciably diminish with frequent plug-in and disconnection, the spring 2 must be constructed with a free length of sufficient magnitude. Furthermore, the spring must be securely supported in the insulating portion of the base of body member 3, as the wiring or circuit plate 4 is not designed for absorption of the torque created by the lateral deflection of the springs. Consequently, there is required, between the points A and B, a distance of about 15 to 20 mm., which, for constructional reasons, cannot be materially reduced.
The relatively long line sections formed by the contact springs not only unfavorably influence crosstalk between adjacent lines, but also result in a substantial increase in wave-resistance over that of the strip lines or conductors on the multilayered construction and circuit plates. Furthermore, the abutting portions cause a deformation of the pulses which must pass over such conductive line sections, and since there must be a delay up to the actual evaluation or further processing of the impulses for the dying out of the buildup processes, there arises therefrom a reduction in the switching speed. Of course, by mounting grounded shield members 342, as illustrated in FIG. 1, on the exterior of the base or body member 3, the L/C ratio of the line section within the plug can be reduced, and thereby the line conduction characteristics can be improved, but a matching to the relatively low wave-resistance of the strip lines is not possible.
Although theoretically there are also known requisite measures for the production of impact-free connections, their use in present applications is usually prohibited by space requirements and cost. For example, in the construction of a system with integrated modules, in practice the raster points at which respective plug-in contacts are to be disposed may have a spacing of 2.54 mm.
The problem underlying the invention thus is that of providing a plug-in connection which can also be utilized for circuit arrangements which operate with pulse lengths in the subnanosecond range. The invention proceeds from the premise that the lengths of the signal paths extending over the connectors must be considerably shortened in order to reduce reflection at the abutment or impact locations to a sufficient degree that they are no longer troublesome.
This is accomplished, according to the invention, in a plugin connector for the detachable electrical connection of lines of a multilayered conductor plate carrying micromodules at one side thereof, with lines of multilayered wiring or circuit plate at predetermined raster points, by an arrangement in which there are disposed perpendicularly to the plane of the conductor plate on the side thereof not occupied by micromodules, contact pins which may be secured in a pinsupporting plate disposed adjacent the conductor plate, and preventing the bending thereof. The free ends of the contact pins protruding from the pin-supporting plate are provided with a tapering configuration in the form of a truncated cone, which are cooperable with contact elements disposed at the corresponding points on the wiring or circuit plate, illustrated as being in the form of spiral or coiled springs, which are connected with the conductor lines. of the circuit plate, each spring being of a size to permit entry of the tapered portion of the cooperable pin, which action is operative to spread the springs and press the turns thereof against one another, as well as in firm engagement with the contact pin.
Referring to FIGS. 2 and 3, there is illustrated a multilayered conductor or assembly plate 5 which may be provided with conductor layers for respective signal lines, as well as conductor layers for voltage supply, etc., which is provided at one side with a plurality of micromodules, indicated generally by the numeral 6.
In the example illustrated, the respective modules 6 are arranged in 12 rows of 12 each, with the exception of the intersection points of the sixth and seventh rows with the sixth and seventh columns, which are not occupied. To provide mechanical reinforcement and support for the respective contact pins 7, there may be provided adjacent the free face of the plate 5 a pin-supporting plate or board 8 of insulating material, which is suitably secured in a protective cover member 9, which thus forms a housing for the modules 6 and associated structure, with the assembly thus described being adapted to be secured in to a cooperable assembly by a screw 10 disposed in the center of the assembly, which may be suitably constructed to prevent complete removal and loss of the screw when separated from the cooperable assembly.
As illustrated in FIG. 3, the pin-supporting board 8 is provided with bores or holes therein, each of which is lined with a metal-conductive layer 8a, formed with annular areas which encircle the respective openings at the outer surfaces of the plate 8. The contact pins 7 are inserted into the respective openings in the plate 8 in engagement with the metallized lining 80 thereof, and suitably secured, for example, by soldering, the diameter of the portions of the pins extending into the pin-supporting plate 8 preferably being less than the diameter of the portions of the pins projecting from the plate, and terminate at their free ends in tapered portions 7' illustrated as being in the form of a truncated cone. The conductor or assembly plate 5, likewise, may be provided at the various raster points with metallized areas 5a, which may be constructed in the same manner as the linings 8a in the pin-supporting board 8 to facilitate connection of the linings 8 with terminals of the micromodules 6. The metalizations 5a and 8a may be suitably conductively connected as, for example, by a soldering or welding process.
Cooperable with the respective contact pins 7 are cooperable contact elements 11, Ila which are mounted on the wiring or circuit plate 12 at each corresponding raster point thereon. The contact element in the embodiment illustrated are in the form of small coiled springs having several turns, for example three, positioned closely one upon the other, with the internal diameter of the spring coil being at least slightly less than the largest diameter of the contact pin 7.
As clearly illustrated in FIG. 3, the wiring plate 12 is provided at each raster point with an opening or bore therethrough, which is lined with a metallized coating 12a terminating in annular areas which encircle the associated bore or hole at the outer surfaces of the plate 12, the lining 12a thus generally corresponding to the lining 8a of the plate 8. Each of the springs 11, 11a is secured, by soldering or other suitable means, to the adjacent annular area of the corresponding lining 12a, with the latter in turn forming conductive connections from one side of the plate 12 to the other. To illustrate the unengaged position of the contact springs 11, the pin 7a in FIG. 3 has been broken away whereby the spring 11a appears in undeformed position. However, when engaged by a cooperable pin, such as the pin 7 of FIG. 3, the respective turns of the spring will be forced outward, generally conforming to the conical surface of the conical end portion 7 of the pin, at the same time applying compression forces to the respective turns, one upon the other, thus providing an extremely short mechanical connection between the pin 7 and the spring lining 12a, as compared, for example, with that of the construction of FIG. 1.
The construction of FIG. 4 is substantially identical with that of FIG. 3 with the exception of the mounting of the respective spring contact elements 11' In this embodiment one end of each coiled spring Il' terminates in an elongated end portion 13, which extends in an axial direction with respect to the centerline of the associated hollow terminal member, and is soldered or otherwise suitably conductively secured thereto.
As illustrated in FIG. 3, the protective cover or housing 9 may be constructed to receive and support the adjacent edges of the pin-supporting board 8, and the lower peripheral edge of the housing may be provided with an insulating layer whereby the housing may be seated upon the plate 12 without creating short circuits, such engagement forming a stop for limiting relative movement between the plates 8 and 12, and thus preventing the application of excessive forces on the contact structure by manipulation of the screw 10.
It will be appreciated from the above disclosure that, while the connector structure according to the present invention may not present a wave resistance matching that of the strip lines on the conductor plates, the signal path extending over the connector is materially shortened to a length of, for example, from 3 to 4 mm., as compared to the considerably greater distances involved in the known construction of FIG. 1.
1. In a plug-in type connector for the releasable connection of electrical lines, at predetermined raster points, between a multilayered assembly plate, including micromodules carried thereon at one side thereof, and conductor lines of multilayered wiring plate, the combination of a plurality of contact pins disposed at respective raster points, means supporting said pins in fixed operative positions with such pins exte nding adjacent and perpendicularly to said assembly plate, means on said supporting means conductively connecting the respective pins to cooperable conductor lines on said assembly plate, the respective pins having a transverse cross section adjacent the free ends thereof which diminishes toward such free ends to a minimum thereat, forming respective tapering end portions, said wiring plate having mounted thereon at each corresponding cooperable raster point a resilient annularly shaped contact element having in its rest position internal dimensions greater than the minimum transverse dimensions of the free end of the cooperable contact pin and less than the maximum transverse dimensions of the tapering portion thereof whereby said pins are operable, upon axial movement toward and into engagement with the respective contact elements to enter the same, with the tapering portion firmly engaging such contact element to effect a conductive connection therewith, and means on said wiring plate effecting conductive connection of said contact elements to respective conductor lines associated with such plate.
2. A connector according to claim I, wherein each of said resilient contact elements comprises a coiled spring, turns of which are expanded and pressed together by engagement therewith of a cooperable contact pin.
3. A connector according to claim 2, wherein said supporting means for the contact pins comprises a platelike member.
4. A connector according to claim 3, wherein said contact pins are mounted in bores in said supporting plate, the diameter of the portions of the pins disposed in said bores being less than that of the adjacent portions of said pins exteriorly of the bore.
5. A connector according to claim 2, wherein one end of each of said coiled springs terminates in an elongated end extending in an axial direction with respect to the centerlines of for securing said assembly and wiring plates in operatively connected relation, with said screw being operable to create contact pressure between the respective contact pins and cooperable contact elements.