US3644989A - Method of jointing electrical cables and tool therefor - Google Patents

Method of jointing electrical cables and tool therefor Download PDF

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Publication number
US3644989A
US3644989A US947A US3644989DA US3644989A US 3644989 A US3644989 A US 3644989A US 947 A US947 A US 947A US 3644989D A US3644989D A US 3644989DA US 3644989 A US3644989 A US 3644989A
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US
United States
Prior art keywords
ferrule
punch
indentation
head
additional
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US947A
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English (en)
Inventor
John Edward Morby
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Alcan Research and Development Ltd
Original Assignee
Alcan Research and Development Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
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Application filed by Alcan Research and Development Ltd filed Critical Alcan Research and Development Ltd
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Publication of US3644989A publication Critical patent/US3644989A/en
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Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R43/00—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors
    • H01R43/04—Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors for forming connections by deformation, e.g. crimping tool
    • H01R43/058—Crimping mandrels
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
    • H01R4/10—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation
    • H01R4/18—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation by crimping
    • H01R4/20—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation by crimping using a crimping sleeve
    • H01R4/203—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation by crimping using a crimping sleeve having an uneven wire-receiving surface to improve the contact
    • H01R4/206—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation effected solely by twisting, wrapping, bending, crimping, or other permanent deformation by crimping using a crimping sleeve having an uneven wire-receiving surface to improve the contact with transversal grooves or threads
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
    • H01R4/58—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation characterised by the form or material of the contacting members
    • H01R4/62—Connections between conductors of different materials; Connections between or with aluminium or steel-core aluminium conductors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R4/00—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation
    • H01R4/58—Electrically-conductive connections between two or more conductive members in direct contact, i.e. touching one another; Means for effecting or maintaining such contact; Electrically-conductive connections having two or more spaced connecting locations for conductors and using contact members penetrating insulation characterised by the form or material of the contacting members
    • H01R4/64—Connections between or with conductive parts having primarily a non-electric function, e.g. frame, casing, rail
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49117—Conductor or circuit manufacturing
    • Y10T29/49174—Assembling terminal to elongated conductor
    • Y10T29/49181—Assembling terminal to elongated conductor by deforming
    • Y10T29/49183—Assembling terminal to elongated conductor by deforming of ferrule about conductor and terminal

Definitions

  • Such insulating materials normally contain a considerable proportion of a high-viscosity wax, which forms on the conductor surface an insulating film difficult to remove either by means of solvents or by mechanical action. Difficulties have also been experienced with insulated cables having dry, solid aluminum, sector conductors.
  • the present invention is therefore directed to providing a means for forming a more efficient compression joint, which leads to the breakdown of any wax film and/or oxide film on the conductor during the indenting of the ferrule to produce an electrical contact between the metal of the ferrule and the conductor of the cable.
  • the ferrules employed for forming compression joints between aluminum conductors are themselves necessarily made of aluminum to avoid corrosion problems due to local electrolytic action.
  • Aluminum metal is subject to'extensive plastic flow when subjected to compression between plain surfaces. It was recognized for the purpose of the present invention that a high interfacial pressure between the inner wall of the ferrule and the surface of the conductor would be necessary to break down the wax film and/or the surface oxide before metal to metal contact could be established.
  • the area on the external surface of the ferrule initially subjected to compression should be small so that the necessary high interfacial pressure could be developed for breakdown of the wax and/or oxide insulating layer.
  • the method of forming the joint must be such as to minimize the metal flow from beneath the indenting punch during compression so as to create maximum interfacial pressure and to avoid the punch breaking through the wall of the ferrule.
  • the present invention provides a method of forming a compression joint between a ductile metal ferrule and a cable inserted therein which comprises subjecting the wall of the ferrule to compression between a support and a punch having a flat head end and a series of surfaces arranged stepwise in relation to the head end and substantially normal to the direction of movement of the punch with the result that as the punch penetrates the ferrule, at successive intervals the surface of the ferrule is engaged by an additional plane surface, which has the effect of gripping a fresh area of the ferrule surface and drawing material into the indented recess in the ferrule wall, the sides of the punch between the successive stepped surfaces being slightly tapered to ensure easy withdrawal of the punch after the formation of the joint.
  • the stepped indenting punch may have any convenient cross section, but for ease in manufacture it is preferably circular or rectangular (including square). When it is rectangular the punch is in the overall form of a four-sided pyramid.
  • the stepped surfaces may be formed on one or both pairs of side faces.
  • the relatively small tip or head end of the punch provides the high local pressure required to break down the wax and/or oxide film on the conductors, while the steps, which are parallel with the head end, grip the metal of the ferrule during the process of indentation, the frictional engagement between the successive step surfaces and the surface of the ferrule thus serving to restrict lateral flow of metal away from the area beneath the head end of the indenting punch.
  • An indenting tool for use in carrying out the method of the present invention comprises a frame or body, having a jaw to receive a backing die or support shaped to act as a seating for the ferrule and a holder for the indenting punch, positioned opposite the jaw and movable towards and away from the jaw.
  • the holder for the indenting punch is preferably in the form of a piston, moving in a cylinder integral with or secured to the body and provided with an inletfor hydraulic fluid, so that the force for application to the indenting punch can be generated by means of a hydraulic pump.
  • the backing die is preferably removable from the jaw so that the backing die employed may be appropriate to the external diameter of the ferrule.
  • the external diameter of the ferrule is in turn governed by the sizes of the cables to be joined.
  • the ferrules have an internal diameter slightly exceeding the diameter of the conductors and have a wall thickness which varies between about 0.1 and 0.3 inches depending upon the sizes of the cables to be jointed. While the bore of the ferrule is in most cases plain, it may also be threaded so as to provide a series of sharp ridges for cutting through the wax film under the pressure of the indenting tool.
  • the method of the invention may be applied to the formation of compression joints between ferrules and both stranded and solid conductors.
  • the included angle at the apex of the punch is preferably 40-70 where the cable is stranded and to 105 where the cable is solid (the included angle being taken as twice the angle at which the plane of any side of the punch lies to the vertical).
  • the sides of the individual steps in the stepped indenting punch are themselves also slightly tapered at an angle, for example, of 515. Useful results are obtainable within a very wide range of variation of interval between successive steps. In general it may be stated that the number of steps should be not less than 5 or greater than per inch of taper.
  • the depth of the successive steps should be in the range of 0.25-0.1 inch.
  • the diameter of the tip of a conical indenting punch should preferably be in the range of 0.05 to 0.25 inch, while in the case of a punch of rectangular cross section the length may be in the range of 0.05 to l inch and the width in the range of0.05 to 0.25 inch.
  • a compression-type jointing tool constructed in accordance with the present invention has been utilized, employing appropriate backing dies, but only a single stepped indenting punch, with a wide range of impregnated aluminum conductor cables in the range of 0.04 to 1 square inch with highly satisfactory results.
  • FIG. 1 is a section of a compression indenting tool for use in applying the method of the present invention
  • FIG. 2 is a side view of a conical indenting punch
  • FIG. 3 is a side view of a pyramidal indenting punch
  • FIG. 4 is a section on the center line of the punch of FIG. 3,
  • FIG. 5 is a view of a compression joint made in accordance with the invention.
  • FIG. 6 is a longitudinal section of one form of ferrule for use in the method of the invention.
  • FIG. 7 is a longitudinal section of a second form of ferrule.
  • the compression indenting tool shown in FIG. 1 comprises a body 1, having a jaw 2, to which a backing die or support 3 of appropriate size can be releasably secured.
  • a cylinder 4 is secured in the body 1 and has a fluid inlet 5 for connection to a hydraulic pump for the supply of hydraulic fluid under pressure.
  • a piston 6 is provided in the cylinder 4 and is retained by an annular retainer 7.
  • the piston 6 carries an indenting punch 8 of the type discussed above.
  • the punch 8 is carried in a recess in the extension 9 of the piston and is secured by a cross pin 10.
  • FIG. 2 One form of indenting tool 8 is illustrated in FIG. 2 and has a shank 11, having an aperture 12 therein for engagement by pin 10.
  • the punch has a flat tip or head surface 14, surrounded by a series of annular surfaces 15, arranged stepwise around the tip or head surface 14.
  • the surface of the steps 16 between successive annular surfaces 15 is tapered at an angle of about 5 in relation to the axis of the punch.
  • the tip or head end surface 24 of the punch is rectangular, having a length approximately three times its width.
  • the included angles between the planes of the major sides 25 and the planes of the minor sides 26 are approximately equal.
  • the sides 26 are not formed with stepped surfaces, but the sides 25 are formed with a series of straight surfaces 27, which lie in planes substantially normal to the axis of the punch, separated by steps 28, which lie at a taper angle of about to the medial plane of the punch.
  • the surfaces and 27 need not be exactly normal to the axis of the punch but may slope inwardly or even to a slight extent outwardly without much effect on the satisfactory operation of the punch.
  • the punch of FIGS. 3 and 4 is mounted so that the surfaces 27 lie lengthwise of the ferrule.
  • the height of the steps are chosen to be less than the thickness of the wall of the ferrule.
  • FIGS. 6 and 7 Two forms of ferrule for use in the method of the invention are illustrated in FIGS. 6 and 7.
  • the ferrule 31 of FIG. 6 is in the form of a simple tube of aluminum or other ductile metal and having a wall 32 of substantial thickness, as indicated below, and a smooth bore 33.
  • the ferrule 41 of FIG. 7 has a wall 42 and a threaded bore 43 for the reasons indicated above.
  • the wall thickness and other dimensions of a ferrule for connecting a particular size of cable are the same for both the ferrule of FIG. 6 and the ferrule of FIG. 7.
  • the wall thickness of aluminum ferrules for use in connec tion with the method of the present invention may have a wall thickness varying between about 0.15 inches and about 0.30 inches, for ferrules varying between about 0.25 and l inch internal diameter, the larger the internal diameters of the ferrule requiring in general greater wall thicknesses.
  • FIG. 5 A compression joint made in accordance with the invention is illustrated in FIG. 5 and may employ a ferrule of the type in either of FIG. 6 or FIG. 7.
  • the ends of two stranded cables 44 and 45 are cleaned by brushing with a wire brush and are inserted into a ferrule 31 of appropriate interior diameter and the wall of the ferrule is deformed by means of the indenting tool already described as indicated at 46.
  • the wall of the ferrule should be indented in the case of a stranded cable, as indicated in FIG. 5, for a distance approximating to half the external diameter of the ferrule and to a lesser extent where the conductor is solid, although no hard and fast rule can be laid down.
  • a method of forming a compression joint between a ductile metal ferrule and a cable inserted therein, by indentation of the ferrule which comprises:
  • a method according to claim 1 which includes successively engaging the metal of the ferrule with surfaces extending longitudinally inward of the indentation in the successive longitudinal spaces among the head and additional punch surfaces, said longitudinal surfaces being tapered toward said head Kunch surface.
  • a method according to claim 1 for forming said joint between the ferrule and a stranded conductor constituting said cable which includes continuing said progressive increasing of said indentation, to indent the ferrule wall by a distance equal to approximately half the external diameter of the ferrule.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Manufacturing Of Electrical Connectors (AREA)
US947A 1969-01-08 1970-01-06 Method of jointing electrical cables and tool therefor Expired - Lifetime US3644989A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0255/69A GB1262951A (en) 1969-01-08 1969-01-08 Improved jointing method for cables

Publications (1)

Publication Number Publication Date
US3644989A true US3644989A (en) 1972-02-29

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Family Applications (1)

Application Number Title Priority Date Filing Date
US947A Expired - Lifetime US3644989A (en) 1969-01-08 1970-01-06 Method of jointing electrical cables and tool therefor

Country Status (7)

Country Link
US (1) US3644989A (de)
CA (1) CA945745A (de)
DE (1) DE2000573B2 (de)
FR (1) FR2027939A1 (de)
GB (1) GB1262951A (de)
NL (1) NL142026B (de)
ZA (1) ZA7034B (de)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5193379A (en) * 1990-09-27 1993-03-16 Burndy Corporation Dieless compression head
US6101862A (en) * 1998-05-20 2000-08-15 Framatome Connectors Usa, Inc. Hydraulic compression tool
US20090064754A1 (en) * 2007-09-10 2009-03-12 John Mezzalingua Associates, Inc. Hydraulic compression tool for installing a coaxial cable connector and method of operating thereof
US20110173810A1 (en) * 2007-09-10 2011-07-21 John Mezzalingua Associates, Inc. Pneumatic compression tool and method of usingthe compression tool to attach a cable connector
US8516696B2 (en) 2007-09-10 2013-08-27 John Mezzalingua Associates, LLC Hydraulic compression tool for installing a coaxial cable connector and method of operating thereof
US8595928B2 (en) 2007-09-10 2013-12-03 John Mezzalingua Associates, LLC Method for installing a coaxial cable connector onto a cable
US8661656B2 (en) 2007-09-10 2014-03-04 John Mezzallingua Associates, LLC Hydraulic compression tool for installing a coaxial cable connector and method of operating thereof
WO2015026696A1 (en) * 2013-08-21 2015-02-26 Tyco Electronics Corporation Filters for terminal crimping devices using ultrasonic signals
US20170302044A1 (en) * 2016-04-14 2017-10-19 Hubbell Incorporated Portable dieless hand held power tools
US10819077B2 (en) 2007-09-10 2020-10-27 John Mezzalingua Associates, LLC Compression tool with biasing member

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2164013A5 (de) * 1971-12-09 1973-07-27 Materiel Electr Indl
US4942757A (en) * 1989-03-31 1990-07-24 Burndy Corporation Hydraulic press with infinite head rotation

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3499098A (en) * 1968-10-08 1970-03-03 Bell Telephone Labor Inc Interconnected matrix conductors and method of making the same
US3509608A (en) * 1967-02-17 1970-05-05 Gen Electric Tab welded joint and method of making
US3514528A (en) * 1967-11-13 1970-05-26 Jimmy C Ray Insulation piercing connector for wires
US3515795A (en) * 1967-12-14 1970-06-02 Thomas & Betts Corp Connector for electrical conductors with deformable side panels for contact with such conductors
US3525799A (en) * 1968-05-17 1970-08-25 Raychem Corp Heat recoverable connector

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3509608A (en) * 1967-02-17 1970-05-05 Gen Electric Tab welded joint and method of making
US3514528A (en) * 1967-11-13 1970-05-26 Jimmy C Ray Insulation piercing connector for wires
US3515795A (en) * 1967-12-14 1970-06-02 Thomas & Betts Corp Connector for electrical conductors with deformable side panels for contact with such conductors
US3525799A (en) * 1968-05-17 1970-08-25 Raychem Corp Heat recoverable connector
US3499098A (en) * 1968-10-08 1970-03-03 Bell Telephone Labor Inc Interconnected matrix conductors and method of making the same

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5193379A (en) * 1990-09-27 1993-03-16 Burndy Corporation Dieless compression head
US5291772A (en) * 1990-09-27 1994-03-08 Burndy Corporation Compression tool ram
US6101862A (en) * 1998-05-20 2000-08-15 Framatome Connectors Usa, Inc. Hydraulic compression tool
US8516696B2 (en) 2007-09-10 2013-08-27 John Mezzalingua Associates, LLC Hydraulic compression tool for installing a coaxial cable connector and method of operating thereof
US8661656B2 (en) 2007-09-10 2014-03-04 John Mezzallingua Associates, LLC Hydraulic compression tool for installing a coaxial cable connector and method of operating thereof
US20110173810A1 (en) * 2007-09-10 2011-07-21 John Mezzalingua Associates, Inc. Pneumatic compression tool and method of usingthe compression tool to attach a cable connector
US20110179639A1 (en) * 2007-09-10 2011-07-28 John Mezzalingua Associates, Inc. Pneumatic compression tool and method of using the compression tool to attach a cable connector
US8272128B2 (en) 2007-09-10 2012-09-25 John Mezzalingua Associates, Inc. Method of using a compression tool to attach a cable connection
US20090064754A1 (en) * 2007-09-10 2009-03-12 John Mezzalingua Associates, Inc. Hydraulic compression tool for installing a coaxial cable connector and method of operating thereof
US8595928B2 (en) 2007-09-10 2013-12-03 John Mezzalingua Associates, LLC Method for installing a coaxial cable connector onto a cable
US7908741B2 (en) 2007-09-10 2011-03-22 John Mezzalingua Associates, Inc. Hydraulic compression tool for installing a coaxial cable connector
US11539179B2 (en) 2007-09-10 2022-12-27 John Mezzalingua Associates, LLC Compression tool with biasing member
US9246294B2 (en) 2007-09-10 2016-01-26 John Mezzalingua Associates, LLC Tool for attaching a cable connector to a cable
US10819077B2 (en) 2007-09-10 2020-10-27 John Mezzalingua Associates, LLC Compression tool with biasing member
US10090627B2 (en) 2013-08-21 2018-10-02 Te Connectivity Corporation Filters for terminal crimping devices using ultrasonic signals
WO2015026696A1 (en) * 2013-08-21 2015-02-26 Tyco Electronics Corporation Filters for terminal crimping devices using ultrasonic signals
US10109971B2 (en) * 2016-04-14 2018-10-23 Hubbell Incorporated Portable dieless hand held power tools
US20170302044A1 (en) * 2016-04-14 2017-10-19 Hubbell Incorporated Portable dieless hand held power tools

Also Published As

Publication number Publication date
FR2027939A1 (de) 1970-10-02
NL142026B (nl) 1974-04-16
CA945745A (en) 1974-04-23
NL7000213A (de) 1970-07-10
GB1262951A (en) 1972-02-09
DE2000573B2 (de) 1971-11-04
ZA7034B (en) 1971-08-25
DE2000573A1 (de) 1970-07-16

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