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Publication numberUS3851297 A
Publication typeGrant
Publication dateNov 26, 1974
Filing dateMay 29, 1973
Priority dateJun 17, 1972
Also published asCA985388A1, DE2329426A1, DE2329426B2, DE2329426C3
Publication numberUS 3851297 A, US 3851297A, US-A-3851297, US3851297 A, US3851297A
InventorsG Munro
Original AssigneeAmp Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Substrate connector
US 3851297 A
Abstract
The invention concerns connectors having an elongate spring body of elastomer or formed as a tubular spring about which a single layer wire coil is wound. The coil turns are separated by cutting the coil longitudinally of the body to define discrete conductive paths of C-shape extending round part of the circumferential profile of the body. Exposed surface portions of the wires present contact points in a row along the body. Each C-shaped turn may present a pair of diametrically opposite contacts. The coil may be wound about a former disposed beside the spring body so that on cutting the turn portions at the former leads to the individual C-shaped turn portions extend freely from the spring body.
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Description  (OCR text may contain errors)

nited States Patent [191 unro 1 1 SUBSTRATE CONNECTOR [75] Inventor: Geoffrey Hector .lames Munro, St.

' Pierre Du Bois, Guernsey (Channel Is.) [73] Assignee: AMP Incorporated, Harrisburg, Pa. [22] Filed: May 29, 1973 [21] Appl. No.: 364,851

[30] Foreign Application Priority Data June 17, 1972 Great Britain 28483/72 [52] US. Cl 339/61 M, 339/17 L, 339/176 MP [51] Int. Cl. l-l05k 1/07 [58] Field 01 Search 339/17, 61, 59, 75 MP, 339/176 MF, 176 MP [56] References Cited UNITED STATES PATENTS 2,480,142 8/1949 Lager 339/61 R X 2,858,515 10/1958 Thunander et al. 339/17 LC 2,980,874 4/1961 Tarbox 339/17 F X 3,059,211 10/1962 Thomas et a1 339/17 F 3,188,601 6/1965 De Tar 339/75 MP 3,221,286 11/1965 Fedde 339/17 F 3307,13) 2/1967 Prise 339/17 F X 3,362,005 1/1968 Corns 339/17 M X 3,401,369 9/1968 Palmateer et al.. 339/17 LC 3,444,503 5/1969 Mallery 339/17 L X [111 3,851,297 Nov. 26, 1974 3,533,049 10/1970 Thompson 339/17 F X 3,818,414 6/1974 Davies et a1 339/17 M OTHER PUBLICATIONS Dunman, Printed Circuit Connector" IBM Technical Disclosure Bulletin, Vol. 7 No. 3, page 182, August 1964.

Primary Examiner-Roy D. Frazier Assistant ExaminerLawrence .1. Staab Attorney, Agent, or Firm-Wi1liam .l. Keating; Frederick W. Raring; .lay L. Seitchik [57] ABSTRACT The ipvention concerns connectors having an elongate spring body of elastomer or formed as a tubular spring about which a single layer wire coil is wound. The coil 7 Claims, 8 Drawing Figures This invention relates to electrical connectors and their method of manufacture. It is particularly but not exclusively concerned with connectors for connecting to or interconnecting lamina circuits such as are formed on printed circuit boards or substrates.

There is increasing need to effect releasable connection to circuit boards or substrates containing large numbers of integrated circuits and presenting large numbers of closely spaced connection points. It is important that such boards or substrates can readily be released from their interconnection within a greater circuit package for maintenance purposes. Conventional connectors have largely proved unsatisfactory in adaptation to the small sizes of connector and small contact pitch required.

It is an object of the present invention to provide a connector of a kind suitablefor manufacture in small sizes with small contact pitch and to provide an economic manner of manufacture for such a connector.

An electrical connector according to the present invention comprises an elongate spring body having a generally uniform cross-section, which is resiliently deformable transversely of its length and which has discrete conductive paths disposed in insulating spaced relationship around the body in which each path comprises a conductor wire of generally C-shaped turn form extending around part only of the circumferential periphery of and bonded to the body, exposed surface portions of the wire turns defining at least'a row of contact points distal from and extending along the spring body.

In one embodiment the wire of each C-shaped turn of at least one of the ends of theC-shape extends freely away from the spring body as a lead.

Suitably, the C-shaped turns extend around more than half of the circumferential periphery of the body and present diametrically opposite rows of contact points extending longitudinally of the body.

The spring body may be formed of elastomeric insulating material or for example it may be formed as a tubular spring of C-shaped cross-section. Such a spring may be ofmetal in which case the spring turns are insulated from the metal.

In a method of manufacture of an electrical connector according to the present invention, a single layer coil of conductor wire is wound around the spring body to extend longitudinally in closely spaced turns, the turns being bonded to the body and the coil being cut longitudinally of the body to separate adjacent turns which define the discrete conductive paths.

In a particular form of this method, the spring body is initially located beside a former body extending longitudinally of and projecting laterally from the spring body, the coil being wound in turns about the two bodies and cut longitudinally of the coil at turn portions around the former body, the former body being removed and wire portions extending from one or both ends of each of the separated turns. Suitably, a pair of connectors may be made simultaneously by disposing a former body between a pair of spring bodies, and winding the coil about the three bodies. The turns are then cut longitudinally of the former at locations between the spring bodies.

In order to reduce the offset effect due to the helical nature of coil turns, the spring body is suitably elastically deformed prior to winding the coil in the same sense as the lead of the coil, and is held in that condition until after the coil cutting operation when the deformation is relaxed. The coilturns are thus flattened.

The invention will now be described by way of example with reference to the accompanying partly diagrammatic drawings, in which:

FIG. I is a perspective view of a connector;

FIG. 2 is an end view of the connector of FIG. 1;

FIG. 3 is a fragmentary perspective view of a printed circuit board assembly including a connector according to FIGS. 1 and 2;

FIG. 4 is an enlarged fragmentary longitudinal section of part of the connector of FIGS. 1 and 2;

FIG. 5 is a fragmentary perspective view of a stage in the manufacture of a connector according to FIGS. I and 2;

FIG. 6 is a sectional view of a printed circuit edge connector embodying connectors according to FIGS. 1 and 2;

FIG. 7 is a fragmentary perspective view partially sectioned of a connector block assembly embodying the invention; and

FIG. 8 is an elevation of a spring body in relaxed, and deformed conditions established during manufacture of a connector according to the invention.

The connector of FIG. 1 comprises a tubular spring member 1 having a generally C-shaped cross-section with a longitudinally extending open seam 2 which may be closed by resilient deformation of the spring. The tubular spring is of metal but alternatively it could be of resilient insulating material or a body of elastomeric insulating material could be substituted for the tubular spring. A series of parallel wires 3 extend generally tangentially from the spring 1 and the wires terminate with arcuate portions 4 extending around and bonded to the tubular spring 1 in insulating spaced relationship. The wires are suitably insulated with a varnish type insulation and diametrically opposite parts of the arcuate portions 4 are cleaned of insulation on sides distal from the spring 1. The bare metal exposed is spot plated with contact metal such as gold or tin at 7 to provide rows 5 of contact points 6. The adhesive bonding material as seen in FIG. 4 secures the arcuate portions in insulating spaced relationship and allows flexure of the arcuate portions 4 concomitant with flexure of the tubular spring 1.

In use, as seen in FIG. 3, the connector of FIGS. 1 and 2 is clamped between opposed faces of adjacent circuit boards 9 with the tubular spring I compressively flexed between the boards. Groups of contact points 6 engage respective contacts of the circuit boards to effect desired interconnections between the upper and lower boards and to input or output circuits through the lead wires 3.

In order to manufacture a connector of this kind, as seen in FIG. 5, tubular springs l are suitably sprung onto opposite ends of a former 10 adapted to open the spring scams 2. The former is provided with longitudinal grooves II at opposite sides for wire cutting purposes as will be described. The external arcuate surfaces of the springs are coated with adhesive 8, FIG. 4, and a single layer coil of wire wound around the former in a series of closely spaced turns. After setting of the bonding adhesive, desired contact points 6, FIG. 4 are cleaned by a skimming or grinding process and the exposed Wire portions spot plated with a suitable contact metal 8, such as gold or tin. The wire coil is cut along the grooves 11 to separate the two connectors which are then removed from the former 10.

The wire ends 3 extend from both sides of the open seam 2 of each connector, and due to the expansion of these seams during the manufacture, the arcuate portions 4 of the wires extend around more than a semicircle when the spring is relaxed. The contact rows are suitably diametrically opposite in this condition. The wire ends 3 may be selectively removed or grouped into bundles according to the particular circuit connections required.

In the edge connector'of FIG. 6 a pair of connectors according to FIGS. 1 and 2 is positioned one on each side of a slot 12 in a housing 13. The springs l are arranged with arcuate portions projecting into the slot 12 with the rows of contact points 6 disposed to engage opposite sides of a printed circuit board 14. The wire ends 3 lead out from the housing for circuitry connection purposes.

It will be appreciated that the manufacture of the connector by coil winding techniques will normally result in diametrically opposite contact points 6 ofa conductor portion 4 being helically offset by half ofa pitch. Where fine wires are used on a close pitch and it is intended that a complementary contact surface of a printed circuit board will engage a plurality of contact points as a group, the half pitch offset is not material.

However, in situations where it is intended that the complementary printed circuit or substrate circuit will engage but a single contact point 6 then precautions must be taken to ensure selection of the appropriate contact points on diametrically opposite portions of the connector. In such situations it may be desirable to wind the arcuate portions 4 as flat turns or after winding the coil to displace marginal portions of the C- shaped spring bordering the open seam laterally in opposite directions in order to flatten the coil turns. This may suitably be effected by initially stressing the spring laterally in the sense of coil winding, in order elastically to deform the spring by an amount corresponding to the coil pitch and after winding the coil and bonding the turns, allowing the spring to relax from the stress to flatten the turns.

In an embodiment of the invention as shown in FIG. 7 the connector spring body is contained in an insulating housing comprising identical halves 16, 17 snapfitting together and about the spring body 1. Each housing half I6, 17 contain means, not shown, to engage ends of the spring body 1 at each side of the seam and arranged on closure of the two housing halves l6, 17 together to displace marginal portions of the spring body on each side of the seam relatively laterally in order to flatten the coil turns 4.

Each housing half I6, 17 has a groove-like recess 18, I9 receiving the spring body 1, and a plurality of passageways 20, 21 extending transversely of the recess and intersecting the recess generally tangentially of the spring body. Conductor wires 22 may be threaded into the passageways and clamped in position by resilient pressure of the spring body 1 which provides mechanical retention and contact pressure. Such an arrangement is applicable to flat flexible or tape cables, in which case a slot is provided for reception of the multiconductor cable in place of a plurality of passageways 22.

In FIG. 8 a spring body 1 of C-shaped section showing in broken lines 1 how it may be elastically deformed by lateral displacement on opposite sides of the seam prior to coil winding so that on relaxation afterwards, the helical coil turns are flattened. It will be appreciated that the broken line position represents a single turn helix of the same pitch and lead sense as the coil winding.

What is claimed is:

1. An electrical connector comprising an elongate spring body having a generally uniform cross-section, which is resiliently deformable transversely of its length and which has discrete conductive paths disposed in insulating spaced relationship around the body, said conductive paths comprising a conductor wire coil wound around said spring body and being disposed in closely uniformly spaced turns along said body, said conductor wire being bonded to said body and having a portion removed from each said turn thereby forming said discrete conductive paths, each path being of generally C-shaped turn form extending around part only of the circumferential periphery of the spring body, each path further comprising a lead portion extending freely away from said spring body, said lead portion being an integral part of the coil wound conductor wire, and exposed surface portions of the wire on each said turn defining at least a row of contact points distal from and extending along the spring body.

2. A connector as claimed in claim 1, in which the C- shaped turns extend around more than half of the circumferential periphery of the body and present diametrically opposite rows of contact points extending longitudinally of the spring body.

3. A connector as claimed in claim 2, in which the spring body is formed of elastomeric insulating material.

4. A connector as claimed in claim 2, in which the spring body is a tubular form of C-shaped cross-section.

points extending longitudinally of the spring body.

7. A connector as claimed in claim 2 in which the contact points are defined by spot depositions of metal plating on the exposed wire surface portions.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2480142 *Sep 21, 1945Aug 30, 1949Fred LagerElectric contact
US2858515 *Aug 12, 1954Oct 28, 1958Westinghouse Electric CorpElectrical connector with resilient gripping means
US2980874 *Sep 16, 1957Apr 18, 1961Tarbox John WElectric winding
US3059211 *May 24, 1960Oct 16, 1962Thomas & Betts CorpElectrical connector for flat conductor carriers
US3188601 *Aug 15, 1962Jun 8, 1965Litton Prec Products IncElectrical connector for tape-like electrical cable
US3221286 *Jul 31, 1961Nov 30, 1965Sperry Rand CorpConnector for printed circuit strip transmission line
US3307139 *May 12, 1965Feb 28, 1967Lockheed Aircraft CorpFlat cable connector
US3362005 *Jun 26, 1967Jan 2, 1968Berg Electronics IncHinge type connector for circuit boards
US3401369 *Jun 7, 1966Sep 10, 1968IbmConnector
US3444503 *Jun 7, 1967May 13, 1969Bell Telephone Labor IncConnector for electrical circuit board
US3533049 *Oct 30, 1967Oct 6, 1970Mb Metals LtdStrip cable connector
US3818414 *Mar 1, 1972Jun 18, 1974Plessey Handel Investment AgElectrical connectors
Non-Patent Citations
Reference
1 *Dunman, Printed Circuit Connector IBM Technical Disclosure Bulletin, Vol. 7 No. 3, page 182, August 1964.
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3951493 *Aug 14, 1974Apr 20, 1976Methode Manufacturing CorporationFlexible electrical connector and method of making same
US3985413 *Sep 6, 1974Oct 12, 1976Amp IncorporatedMiniature electrical connector
US4820170 *Jan 27, 1988Apr 11, 1989Amp IncorporatedLayered elastomeric connector and process for its manufacture
US4840569 *Jun 27, 1988Jun 20, 1989Itt CorporationHigh density rotary connector
US4897054 *Mar 15, 1989Jan 30, 1990Amp IncorporatedModular circuit board bussing connector
US5013248 *Nov 30, 1989May 7, 1991Amp IncorporatedMulticircuit connector assembly
US5161981 *Mar 10, 1992Nov 10, 1992Amp IncorporatedFoldable stacking connector
US5230632 *Dec 19, 1991Jul 27, 1993International Business Machines CorporationDual element electrical contact and connector assembly utilizing same
US5299939 *Mar 5, 1992Apr 5, 1994International Business Machines CorporationSpring array connector
US5475921 *Aug 4, 1993Dec 19, 1995The Wiremold CompanyMethod for making contact assembly
US5540594 *Jun 29, 1994Jul 30, 1996The Whitaker CorporationElastomeric connector having increased compression range
US5823792 *Mar 10, 1997Oct 20, 1998Molex IncorporatedWire-wrap connector
US5999414 *Mar 14, 1997Dec 7, 1999California Institute Of TechnologyPhysically separating printed circuit boards with a resilient, conductive contact
US7121837 *Mar 14, 2003Oct 17, 2006Fujitsu Component LimitedConnector
US7654827 *Aug 28, 2007Feb 2, 2010Japan Aviation Electronics Industry, LimitedElectrical connector having a space allowing an elastic connecting member to be escaped
US8127560Jun 1, 2007Mar 6, 2012Carleton Life Support Systems, Inc.Machined spring with integral retainer for closed cycle cryogenic coolers
US8378218Nov 13, 2009Feb 19, 2013Carleton Life Support Systems, Inc.Spring with multiple conducting coils
US8398443 *Dec 18, 2006Mar 19, 2013Roche Diagnostics Operations, Inc.Biological testing system and connector therefor
EP0036933A2 *Feb 11, 1981Oct 7, 1981Bohdan UlrichPluggable connector and its use in making a disconnectible electrical connection
WO1998040931A1 *Feb 23, 1998Sep 17, 1998Molex IncWire-wrap connector
Classifications
U.S. Classification439/591, 439/787, 439/723, 439/66, 439/637
International ClassificationH01R13/33, H01R12/16, H01R4/00, H01R13/00, H01R12/18, H01R43/00, H05K3/32
Cooperative ClassificationH01R12/7082, H01R12/87, H01R13/33, H01R12/79
European ClassificationH01R12/79, H01R12/70E, H01R13/33