Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3798589 A
Publication typeGrant
Publication dateMar 19, 1974
Filing dateSep 27, 1972
Priority dateSep 27, 1972
Publication numberUS 3798589 A, US 3798589A, US-A-3798589, US3798589 A, US3798589A
InventorsDeardurff L
Original AssigneeOwens Corning Fiberglass Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Electrical lead
US 3798589 A
Abstract
An electrical lead suitable for use in ignition systems for internal combustion engines including an electrical conductor fully surrounded by insulation with an exposed conductor portion extending from the insulation at one end of the lead; and an electrically conductive termination cap fastened at one end including a closed central portion oriented transversely of the conductor in pressed electrically conductive contact with the exposed conductor portion.
Images(1)
Previous page
Next page
Description  (OCR text may contain errors)

United States Patent [1 1 Deardurfi Mar. 19, 1974 ELECTRICAL LEAD [75] Inventor: Lawrence R. Deardurff, Newark,

Ohio

[73] Assignee: Owens-Corning Fiberglass Corporation, Toledo, Ohio [22] Filed: Sept. 27, 1972 [21] App]. No.: 292,577

[52] US. Cl 339/223 S, 339/100, 339/256 C, 174/74 R, 338/66 [51] Int. Cl ..l-l01r 15/12 [58] Field of Search 339/223 R, 223 S, 256 C, 339/275 R, 275 T, 276 T, 100, 250; 338/66, 214, 266, 272, 322, 332; 174/74 R; 117/229 [5 6] References Cited UNITED STATES PATENTS 2.969,520 l/l96l Waldo 339/105 3,247,020 4/1966 Shulver et al 117/226 l,()56,65l 3/l9l3 Fuile 339/250 X 2,426,845 9/1947 Rogoff 339/223 S 2,965,871 l2/l960 Seyfarth r 339/l00 2,035,947 3/l936 Davis 339/100 Primary Examiner-Joseph H. McGlynn Assistant Examiner Albert A. Hafe1 Attorney, Ag'h: or F irm-Staelin & Overman; Ronald C. Hudgens 57 ABSTRACT An electrical lead suitable for use in ignition systems for internal combustion engines including an electrical conductor fully surrounded by insulation with an exposed conductor portion extending from the insulation 8 Claims, 11 Drawing Figures PATENTED MR 1 9 I974 .....H wwwmmwmmmwm II! A ELECTRICAL LEAD BACKGROUND OF THE INVENTION In recent years ignition cables used with internal combustion engines in vehicles have used electrical conductors of non-conducting elongated support eIe ments like bundles of glass filaments coated with electrically conductive material such as graphite. Many electrical terminations have been tried with these cables.

But prior termination arrangements have had drawbacks. For example, staple type terminations tend to damage a multifilament conductor. Without great care and proper application this damage tends to develop a high resistance electrical short in a conductor that can be especially detrimental to conductors using material like glass filaments with a conductive coating on them. High resistance shorts develop heat that can melt glass filaments; this heat can cause small insulating glass balls or spheres to be formed that augment the short in the initially damaged region of the conductor.

A similar result can occur when a termination staple makes nonuniform contact with a multifilament conductor.

High resistance shorts are difficult to determine until the ignition cable has been used for some time, for example on automobiles after purchase. Hence, the problem can cause considerable difficulty.

Another type of ignition cable termination, known as strip and fold, does not cause high resistance shorts. But this type of termination requires a considerable length of exposed conductor at each end of an ignition cable; in practice /1 of an inch or more of exposed conductor used at each end of a cable. The exposed conductor is folded back along the cable. A conductive termination cap is clamped onto the cable to effect electrical contact with the conductor along the length of the cable.

'A major drawback to strip and fold type of terminations is economic. Literally millions of ignition cables are produced daily. And the length of exposed conductor required to effect a satisfactory electrical connection is considerable. Accordingly, a satisfactory termination using less exposed conductor would effect considerable savings in material. Furthermore, in production strip and fold type terminations require slow and elaborate production methods to insure electrical contact between the termination cap and the exposed fold-back portion of the conductor.

Hence, there is a commercial need for another type of electrical lead suitable for use in ignition systems.

SUMMARY OF THE INVENTION An object of the invention is an improved electrical lead, especially one suitable for use in ignition systems.

Another object of the invention is an improved electrical lead using a relatively tightly packed bundle of glass filaments coated with electrically conductive material.

Yet another object of the invention is a more economically produced improved electrical lead.

The above and other objects are attained by an electrical lead comprising an elongated body capable of conducting electricity with the body fully surrounded by electrical insulation and having an exposed portion extending from one end of the lead; fastened at the one end is an electrically conductive termination cap that includes a closed end portion in pressed electrical contact with the exposed portion of the body.

The above and other objects and advantages will become more apparent as the invention is more fully described hereinafter with reference made to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation view of a automotive distributor using electrical leads according to the invention.

FIG. 2 is an enlarged side elevation viewof a portion of the distributor taken along the lines 2-2 shown in FIG. 1. This section view shows an embodiment of an end of an electrical lead according to the invention in place in the distributor shown in FIG. 1.

FIG. 3 is an exploded view in perspective of the electrical lead shown in FIGS. 1 and 2.

FIG. 4 is a side elevation view of the end region of the insulated conductor shown in FIGS. 1-3. FIG. 4 shows an exposed portion of the conductor projecting a short distance a from the end of the insulation.

FIG. 5 is a side elevation view of the termination cap used with the lead shown in FIGS. 1-3.

FIG. 6 is a side elevation view, partially in section, showing another lead according to the invention.

FIG. 7 is a side elevation view, in section, of the end region of another termination cap according to the invention.

FIG. 8 is a side elevation view in section of the end region of yet another termination cap according to the invention.

FIG. 9 is a side elevation view in section of the end region of still another termination cap according to the invention.

FIG. 10 is a view in perspective of another embodiment of an electrical lead according to the invention.

FIG. 11 is a side elevation view, partially in section, of an electrical lead like the lead shown in FIGS. 1-3 but modified to connect with a spark plug. The lead is shown on a spark plug but without the usual flexible spark plug cover.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 and 2 show an embodiment of the invention used with a conventional distributor 10 in an automotive ignition system. The ignition leads 12 connect the distributor 10 with spark plugs; the lead 14 connects the distributor 10 with a high tension or voltage source such as an ignition coil. In the embodiment shown the leads 12 and 14 use the same termination arrangements with the distributor 10.

As can be more clearly seen from the cross sectional view of FIG. 2 each of the leads 12 and 14 extends into the interior of a tubular sleeve 16 that is integral with the distributor cap 18. A cup-shaped member or insert 20 of conducting metal defines the lower portion of the inner wall of each of the sleeves 16. Each of the members 20 provides an extension 22 that forms an internal distributor contact for engagement with the rotor of the distributor 10. The leads 12 fit in snug-fit relation with the insert 20 within the tubular sleeve 16 to obtain good electrical contact.

Referring more particularly to FIGS. 2 through 4, it can be seen that the lead 12 includes an electrical cable comprising a conductor 30 surrounded along its length by a sheath or coating 32 of insulating material. An electrically conductive cap 34 terminates the lead 12.

As shown the conductor 30 is an elongated bundle of relatively closely or tightly packed together continuous glass filaments 36 having a thin electrically conducting film or coating on them formed of small conductive particles such as graphite. U.S. Pat. No. 3,247,020 discloses a method for adhering electrically conducting materials to glass filaments to form an electrically conductive film.

Besides graphite particles, a number of electrically conductive particles can be used to coat the glass filaments. For example, it is possible to use dispersions or colloidal suspensions of carbon black to form a coating of carbon black particles on the glass filaments. Further, it is possible to use metals and organometallic compositions that decompose under heat to form a metallic electrically conductive coating.

Other non-conducting filaments with an electrically conductive film on them can be used. For example, it is possible to use cotton, rayon, polyester, and various blends or mixtures thereof. Also, it is possible to use filaments or wires of conductive material such as silver, copper, and the like. Moreover, the invention embraces the use of monofilament conductors besides a grouping of elongated conductive elements.

The electrical insulating sheath 32 is a simple conventional single layer of elastomeric electrical insulating material. However, any suitable electrical insulating constructions can be used.

An exposed portion 38 of the conductive bundle 30 projects axially from the insulation 32 at one end of the lead 12. In practice, this portion 38 extends only a short distance beyond the end of the insulation; this distance is indicated as a in FIG. 4. Normally the distance a is not greater than the thickness of the insulating sheath 32 surrounding the conductor 30. In practice, an exposed portion 38 having a length a of from Vs to A of an inch has given good results in ignition systems.

As shown the termination cap 34 is an electrically conductive metal member fastened at the end of the lead 12. The cap 34 includes a closed end portion 40 oriented for extension generally transversely of the cable and arms 42 for extension along the length of the cable (conductor 30). The arms 42 are fashioned with pointed push points 44; the points 44 are embedded in the insulation 32 to fasten the cap 34 in place.

The cap 34 has a central dimpled portion 50 that provides a closed central end portion with a convex surface 52 pressed against the exposed portion 38 of the conductor 30 in electrical conducting communications or contact. And as can be more clearly seen in FIG. 2, the convex surface 52 is pressed or intruded lengthwise into the end of the exposed bundle of glass filaments 36 (portion 38) to establish electrical contact. The filaments 36 are dispersed over the surface 52. And this spread apart relation of the filaments 36 provides a larger electrical contact area between the cap 34 (surface 52) and the coated filaments 36. The surface 52 presses more firmly into the central portion of the bundle 30 located more closely adjacent to the end of the insulation 32.

The convex surface 52 is shown as a spherical surface that defines a circle at its base region; the circle is shown in FIG. 4 as having a diameter d. An annular flange portion 54 is integral with and surrounds the convex surface 52 at its base region. The surface 52 projects a height h above the annular surface 54. Good electrical conduction has resulted with h" smaller than d. Further, good electrical conduction has been obtained with d considerably larger than the diameter of the tightly packed bundle or conductor 30, e.g. two times larger.

FIG. 6 shows another lead, denoted by the reference numeral 12', according to the principles of the invention. The lead 12 uses an electrical termination cap 34 on the insulated conductor shown in FIGS. 1-4. The cap 34 includes a closed end portion 40 and a ferrule 56. The ferrule 56 is crimped onto the lead 12'. The end portion 40' provides an interior central convex surface 52' like the convex surface 52 of the cap 34. The cap 34 (convex surface 52) makes electrical contact with the conductor 30' as explained with respect to the lead 12.

FIGS. 7 through 9 show other termination caps according to the invention. FIG. 7 shows a portion of a cap 60 with a curved end portion 62 and a ferrule 64. The end portion 62 provides a concave conductor contacting surface 66. FIG. 8 shows a cap with an end portion 72 and a ferrule 74. The end portion 72 provides a convex surface 76 that is larger in size than the convex surfaces 52 and 54'. As shown the surface 76 comprises the entire internal end surface of the cap 70. FIG. 9 shows a cap 80 with an end portion 82 and a ferrule 84. The end portion 82 provides a planar conductor contacting surface 86. Like the termination cap 34 these additional termination caps are used with insulated conductors having an exposed conductor portion extending from the insulation at one end thereof. These caps are fastened on the insulated conductor with their closed ends in pressed electrical contact with the exposed conductor portion.

FIG. 10 shows a modified lead 92 according to the invention using the insulated conductor shown in FIGS. l-4. However, in FIG. 10 the embodiment uses an electrically conductive termination cap 94 having a striplike closed end portion 96 and arms 98. The end portion 94 provides a planar conductor contacting surface. And in fastened position at the end of the lead 92, this planar surface is in pressed electrical contact with the coated filaments 36 in the exposed portion 38 of the conductor 30. The arms 98 have pins like the pins 44 fashioned in the arms 42 to fasten the cap 34 to the insulation 32.

FIG. 11 shows an electrical lead 12" according to the invention snapped in electrical contact onto a spark plug 100. The lead 12" uses the insulated conductor shown in FIGS. I-4 and a termination cap 34" fastened at the end of the lead 12". The cap 34" is similar to the cap 34, but is modified to include an extension 102 that effects securement of the lead 12" on the spark plug 100. For clarity the lead is shown without the normal flexible protective cover over the end of the lead and the upper portion of the spark plug.

The electrical lead of the invention has been shown as a lead in an ignition system. But the lead has broader use. Hence, it is apparent that modifications and different arrangements can be made within the scope of the invention other than disclosed herein. The disclosure is merely illustrative, the invention comprehending all variations thereof.

I claim:

1. An electrical lead comprising:

an elongated bundle of filaments capable of conducting electricity;

electrical insulation fully surrounding the bundle, an exposed portion of the bundle extending from the insulation at one end of the lead; and 5 an electrically conductive termination cap including a portion defining a convex filament contacting surface and means fastening the cap to the lead with the convex filament contacting surface in pressed electrically conductive contact with the exposed portion of the bundle beyond the terminating end surface of the insulation, the filament contacting surface pressing the convex filaments against themselves and directly against the terminating end surface of the insulation.

2. The lead of claim 1 in which the convex filament contacting surface is curved in all directions.

its length, an exposed end of the bundle projecting beyond the insulation at one end of the lead; and an electrically conductive metal cap fastened at the one end including a convex surface pressed generally lengthwise into the end of the exposed bundle portion with at least some of the filaments of the bundle spread in electrically conductive contact with the convex surface, and pressed between said convex surface and said end of the insulation.

4. The electrical lead of claim 3 in which the coating includes electrically conductive particles.

5. The electrical lead of claim 4 in which the electrically conductive particles are graphite.

6. The electrical lead of claim 3 in which the base of the convex surface is larger than the cross sectional area of the closely packed filaments.

7. The electrical lead of claim 6 in which the convex surface is hemispherically shaped.

8. The electrical lead of claim 7 in which the exposed end of the bundle projects beyond the insulation a distance no greater than the thickness of such insulation.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US1056651 *Mar 31, 1911Mar 18, 1913Edward Hall FaileElectric-cable connector.
US2035947 *Nov 30, 1931Mar 31, 1936Gen Motors CorpConnecter
US2426845 *Nov 17, 1944Sep 2, 1947Burndy Engineering Co IncCable end sealing device
US2965871 *Dec 6, 1956Dec 20, 1960Gen Motors CorpSpark plug lead terminal connection
US2969520 *Sep 19, 1957Jan 24, 1961Aerojet General CoStrain relief for cable connectors
US3247020 *Jan 2, 1962Apr 19, 1966Owens Corning Fiberglass CorpElectrically-conductive elements and their manufacture
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4163597 *Aug 14, 1978Aug 7, 1979Stitt Spark Plug CompanyElectrical connector for a spark plug
US4274695 *Jan 31, 1979Jun 23, 1981Hitachi, Ltd.Device for electrically connecting spark plug to high-voltage cable
US4781812 *Oct 8, 1987Nov 1, 1988Imperial Industries Inc.Simple swaged knob accumulates more build-up before removal; stripped insulated sheath crimped and flattened
US5166477 *May 28, 1991Nov 24, 1992General Electric CompanyCable and termination for high voltage and high frequency applications
US5750928 *Dec 14, 1995May 12, 1998Escallier; BernardMethod of fabrication of electrical cable connector, electrical cable, and high-voltage transformer equipped with such cables
US6902759 *Sep 12, 2002Jun 7, 2005Innovaquartz IncorporatedCoating the glass strand with a metallorganic material, heating the metallorganically coated galss strand to degrade the metallorganic material and drive off the organic portion, leaving a metallic coating, cooling metal coated strand
US7828595Mar 3, 2009Nov 9, 2010John Mezzalingua Associates, Inc.Connector having conductive member and method of use thereof
US7833053Apr 22, 2009Nov 16, 2010John Mezzalingua Associates, Inc.Connector having conductive member and method of use thereof
US7845976Mar 30, 2009Dec 7, 2010John Mezzalingua Associates, Inc.Connector having conductive member and method of use thereof
US7892005May 19, 2010Feb 22, 2011John Mezzalingua Associates, Inc.Click-tight coaxial cable continuity connector
US7950958Nov 8, 2010May 31, 2011John Messalingua Associates, Inc.Connector having conductive member and method of use thereof
US8029315May 26, 2009Oct 4, 2011John Mezzalingua Associates, Inc.Coaxial cable connector with improved physical and RF sealing
US8075338Oct 18, 2010Dec 13, 2011John Mezzalingua Associates, Inc.Connector having a constant contact post
US8079860Jul 22, 2010Dec 20, 2011John Mezzalingua Associates, Inc.Cable connector having threaded locking collet and nut
US8113879Jul 27, 2010Feb 14, 2012John Mezzalingua Associates, Inc.One-piece compression connector body for coaxial cable connector
US8152551Jul 22, 2010Apr 10, 2012John Mezzalingua Associates, Inc.Port seizing cable connector nut and assembly
US8157589May 31, 2011Apr 17, 2012John Mezzalingua Associates, Inc.Connector having a conductively coated member and method of use thereof
US8167635Oct 18, 2010May 1, 2012John Mezzalingua Associates, Inc.Dielectric sealing member and method of use thereof
US8167636Oct 15, 2010May 1, 2012John Mezzalingua Associates, Inc.Connector having a continuity member
US8167646Oct 18, 2010May 1, 2012John Mezzalingua Associates, Inc.Connector having electrical continuity about an inner dielectric and method of use thereof
US8172612May 27, 2011May 8, 2012Corning Gilbert Inc.Electrical connector with grounding member
US8192237Feb 23, 2011Jun 5, 2012John Mezzalingua Associates, Inc.Coaxial cable connector having electrical continuity member
US8272893May 25, 2010Sep 25, 2012Corning Gilbert Inc.Integrally conductive and shielded coaxial cable connector
US8287310Sep 2, 2011Oct 16, 2012Corning Gilbert Inc.Coaxial connector with dual-grip nut
US8287320Dec 8, 2009Oct 16, 2012John Mezzalingua Associates, Inc.Coaxial cable connector having electrical continuity member
US8313345Oct 7, 2010Nov 20, 2012John Mezzalingua Associates, Inc.Coaxial cable continuity connector
US8313353Apr 30, 2012Nov 20, 2012John Mezzalingua Associates, Inc.Coaxial cable connector having electrical continuity member
US8323053Oct 18, 2010Dec 4, 2012John Mezzalingua Associates, Inc.Connector having a constant contact nut
US8323060Jun 14, 2012Dec 4, 2012John Mezzalingua Associates, Inc.Coaxial cable connector having electrical continuity member
US8337229Jan 28, 2011Dec 25, 2012John Mezzalingua Associates, Inc.Connector having a nut-body continuity element and method of use thereof
US8342879Mar 25, 2011Jan 1, 2013John Mezzalingua Associates, Inc.Coaxial cable connector
US8348697Apr 22, 2011Jan 8, 2013John Mezzalingua Associates, Inc.Coaxial cable connector having slotted post member
US8366481Mar 30, 2011Feb 5, 2013John Mezzalingua Associates, Inc.Continuity maintaining biasing member
US8382517May 1, 2012Feb 26, 2013John Mezzalingua Associates, Inc.Dielectric sealing member and method of use thereof
US8388377Apr 1, 2011Mar 5, 2013John Mezzalingua Associates, Inc.Slide actuated coaxial cable connector
US8398421Feb 1, 2011Mar 19, 2013John Mezzalingua Associates, Inc.Connector having a dielectric seal and method of use thereof
US8414322Dec 14, 2010Apr 9, 2013Ppc Broadband, Inc.Push-on CATV port terminator
US8444445Mar 25, 2011May 21, 2013Ppc Broadband, Inc.Coaxial cable connector having electrical continuity member
US8465322Aug 19, 2011Jun 18, 2013Ppc Broadband, Inc.Coaxial cable connector
US8469740Dec 24, 2012Jun 25, 2013Ppc Broadband, Inc.Continuity maintaining biasing member
US8475205Dec 24, 2012Jul 2, 2013Ppc Broadband, Inc.Continuity maintaining biasing member
US8480430Dec 24, 2012Jul 9, 2013Ppc Broadband, Inc.Continuity maintaining biasing member
US8480431Dec 24, 2012Jul 9, 2013Ppc Broadband, Inc.Continuity maintaining biasing member
US8485845Dec 24, 2012Jul 16, 2013Ppc Broadband, Inc.Continuity maintaining biasing member
US8506326Oct 24, 2012Aug 13, 2013Ppc Broadband, Inc.Coaxial cable continuity connector
US8529279Dec 12, 2012Sep 10, 2013Ppc Broadband, Inc.Connector having a nut-body continuity element and method of use thereof
US8550835Apr 11, 2013Oct 8, 2013Ppc Broadband, Inc.Connector having a nut-body continuity element and method of use thereof
US8562366Oct 15, 2012Oct 22, 2013Ppc Broadband, Inc.Coaxial cable connector having electrical continuity member
US8573996May 1, 2012Nov 5, 2013Ppc Broadband, Inc.Coaxial cable connector having electrical continuity member
US8591244Jul 8, 2011Nov 26, 2013Ppc Broadband, Inc.Cable connector
US8597041Oct 15, 2012Dec 3, 2013Ppc Broadband, Inc.Coaxial cable connector having electrical continuity member
US8647136Oct 15, 2012Feb 11, 2014Ppc Broadband, Inc.Coaxial cable connector having electrical continuity member
US8690603Apr 3, 2012Apr 8, 2014Corning Gilbert Inc.Electrical connector with grounding member
US8753147Jul 22, 2013Jun 17, 2014Ppc Broadband, Inc.Connector having a coupling member for locking onto a port and maintaining electrical continuity
US8758050Jun 10, 2011Jun 24, 2014Hiscock & Barclay LLPConnector having a coupling member for locking onto a port and maintaining electrical continuity
Classifications
U.S. Classification439/866, 174/74.00R, 338/66, 439/867
International ClassificationH01T13/04, H01T13/00, H01R4/00
Cooperative ClassificationH01T13/04, H01R2101/00
European ClassificationH01T13/04
Legal Events
DateCodeEventDescription
Jul 31, 1987ASAssignment
Owner name: OWENS-CORNING FIBERGLAS CORPORATION, FIBERGLAS TOW
Free format text: TERMINATION OF SECURITY AGREEMENT RECORDED NOV. 13, 1986. REEL 4652 FRAMES 351-420;ASSIGNORS:WILMINGTON TRUST COMPANY, A DE. BANKING CORPORATION;WADE, WILLIAM J. (TRUSTEES);REEL/FRAME:004903/0501
Effective date: 19870730
Free format text: TERMINATION OF SECURITY AGREEMENT RECORDED NOV. 13, 1986. REEL 4652 FRAMES 351-420;ASSIGNORS:WILMINGTON TRUST COMPANY, A DE. BANKING CORPORATION;WADE, WILLIAM J. (TRUSTEES);REEL/FRAME:4903/501
Owner name: OWENS-CORNING FIBERGLAS CORPORATION, A CORP. OF DE
Nov 13, 1986ASAssignment
Owner name: WADE, WILLIAM, J., ONE RODNEY SQUARE NORTH, WILMIN
Owner name: WILMINGTON TRUST COMPANY, ONE RODNEY SQUARE NORTH,
Free format text: SECURITY INTEREST;ASSIGNOR:OWENS-CORNING FIBERGLAS CORPORATION;REEL/FRAME:004652/0351
Effective date: 19861103
Owner name: WILMINGTON TRUST COMPANY,DELAWARE
Free format text: SECURITY INTEREST;ASSIGNOR:OWENS-CORNING FIBERGLAS CORPORATION;REEL/FRAME:4652/351
Owner name: WADE, WILLIAM, J.,DELAWARE
Owner name: WADE, WILLIAM, J., DELAWARE
Owner name: WILMINGTON TRUST COMPANY, DELAWARE