EP0119467B1 - Verfahren zur Befestigung einer schmiedbaren Metallhülse auf einem Stab aus Verbundmaterial und durch die Ausführung dieses Verfahrens erhaltener Isolator - Google Patents

Verfahren zur Befestigung einer schmiedbaren Metallhülse auf einem Stab aus Verbundmaterial und durch die Ausführung dieses Verfahrens erhaltener Isolator Download PDF

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Publication number
EP0119467B1
EP0119467B1 EP84101546A EP84101546A EP0119467B1 EP 0119467 B1 EP0119467 B1 EP 0119467B1 EP 84101546 A EP84101546 A EP 84101546A EP 84101546 A EP84101546 A EP 84101546A EP 0119467 B1 EP0119467 B1 EP 0119467B1
Authority
EP
European Patent Office
Prior art keywords
sleeve
rod
composite material
electrical insulator
metal
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
Application number
EP84101546A
Other languages
English (en)
French (fr)
Other versions
EP0119467A1 (de
Inventor
Denis Dumora
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.)
Ceraver SA
Original Assignee
Ceraver SA
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
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=9286150&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0119467(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Ceraver SA filed Critical Ceraver SA
Priority to AT84101546T priority Critical patent/ATE25166T1/de
Publication of EP0119467A1 publication Critical patent/EP0119467A1/de
Application granted granted Critical
Publication of EP0119467B1 publication Critical patent/EP0119467B1/de
Expired legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B17/00—Insulators or insulating bodies characterised by their form
    • H01B17/38—Fittings, e.g. caps; Fastenings therefor
    • H01B17/40—Cementless fittings
    • 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
    • Y10T29/49227—Insulator making
    • 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
    • Y10T29/49826—Assembling or joining
    • Y10T29/49908—Joining by deforming
    • Y10T29/49925—Inward deformation of aperture or hollow body wall
    • Y10T29/49934—Inward deformation of aperture or hollow body wall by axially applying force

Definitions

  • the present invention relates to a method for fixing a malleable metal sleeve to a rod of composite material according to the preamble of claim 1.
  • the sleeve may for example be made of steel or of aluminum alloy, while the rod may consist of fibers glass impregnated with synthetic resin.
  • a method according to the preamble of claim 1 is described in document DE-A-1 400 003.
  • the sleeve belongs to an end fitting of an electrical insulator, the rod of which is the insulating element, it is understandable that its attachment to the rod is an extremely critical operation. If one proceeds by mechanical shrinking, it is necessary that the compression is sufficient to ensure the maintenance of the rod in its sleeve, even in the event of significant tensile force; but this compression should not be excessive so as not to risk damaging the fibers and causing cracks.
  • This method has drawbacks because it creates a creep of the metal of the sleeve, perpendicular to the compression forces in two opposite directions, symmetrically with respect to the median plane of the compressed zone; this causes tensile forces in the fibers of the rod in two opposite directions.
  • the application of the compression forces is not homogeneous along all the generatrices of the sleeve, an ovalization of the rod is observed with delamination of the fibers.
  • the known process therefore causes deterioration of the fibers capable of considerably reducing the performance of the insulator concerned.
  • the object of the present invention is to avoid these drawbacks and to propose a method which reduces the risk of deterioration of the rod when the sleeve is compressed. This object is achieved by the method as characterized in claim 1.
  • the elastic elongation limit of the glass fibers E is of the order of 3% while the deformation of the metal can cause the sleeve to lengthen of the order of 6% to 10%.
  • the method according to the invention causes progressive tightening of the sleeve on the rod capable of stretching the fibers in one direction from the inlet of the sleeve, unlike known methods.
  • the compressive force is variable depending on the annular zones considered.
  • the present invention also relates to an electrical insulator obtained by the implementation of the above method. It comprises at least one end fitting having a sleeve in which one end of the rod has been fixed.
  • the inlet of the sleeve has an uncompressed bead on the rod.
  • the fitting 2 comprises a cylindrical sleeve 3 provided with an internal cylindrical housing 6 with an axis 9 and capable of receiving with gentle friction the end 11 of a rod 10 of composite material, for example based on glass fibers impregnated with synthetic resin.
  • the play between the rod and the interior wall of the housing 6 has been deliberately exaggerated in the figure).
  • the end face of the rod 10 applied against the bottom 7 of the housing 6 has been referenced 8.
  • the inlet of the fitting 2 is provided with a bead 5 which will not be compressed on the rod 10.
  • Such an arrangement makes it possible to separate the zones of maximum mechanical stress, which are located in the compressed zone of the fitting 2, zones of maximum electrical stresses which are situated substantially outside the fitting beyond the plane 12.
  • the area of the sleeve interested in the necking is referenced by L. It is limited on the one hand by a plane 13, orthogonal to the axis 9 and located after the bead 5, and on the other hand by a plane orthogonal to the axis 9 and passing substantially through the terminal face 8 of the rod 10.
  • FIG. 3 has shown in solid lines the fitting 2 ′ after shrinking and we have recalled by dotted lines its initial configuration.
  • the sleeve and the fixing end have been referenced respectively 3 'and 4'.
  • the metal of the sleeve is hardened around the end 11 ′ of the rod 10 whose fibers have been drawn only in the direction shown diagrammatically by the arrow 20.
  • FIGS 4 and 5 show very schematically a device for implementing the method which has just been described.
  • Figure 4 shows the device in the starting position (see Figure 1), while the right part shows the device after the shrinking operation has been performed (see Figure 3).
  • This device comprises eight curvilinear sectors 41 to 48; one of them, the sector 41 is seen in the final position and in the initial position in FIG. 4, while they are all seen in FIG. 5 under the references 41 'to 48' in the final position.
  • These sectors are arranged radially with respect to the axis 9 of the rod 10 and are regularly distributed around this axis.
  • a part 51 of the external face of the sector 41 constitutes a compression zone for the constriction.
  • the translational movement 60 of the fitting caused by the rotary movement of the sectors is such that the compression zone of a sector is applied successively at any point in a zone of the sleeve corresponding to the width of the compression zone.
  • the transverse curvature of the sector compression zone is substantially zero. This provision simplifies the manufacturing of sectors but is not compulsory.
  • the number of sectors is of course not limited to eight; it can be modified, for example as a function of the diameter of the sleeve to be shrunk.
  • the longitudinal profile of the compression zone is chosen as a function of the force which it is desired to impart to this or that annular zone of the sleeve.
  • the method according to the invention makes it possible to preserve the fibers of the rod while ensuring the desired attachment for the rod in its sleeve.
  • the following advantage should also be noted, relating to an organic insulator comprising a rod of any length, two constricted fittings and an insulating coating possibly provided with fins. It appears from Figures 1 and 3 that the distance between the planes "entry of the two fittings is not changed by the method according to the invention. It is therefore possible to place the rod and its fittings, directly and without adjustment, in a mold to produce a one-piece insulating coating.

Landscapes

  • Insulators (AREA)
  • Insulating Bodies (AREA)
  • Forging (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Joining Of Building Structures In Genera (AREA)
  • Dowels (AREA)
  • Gripping Jigs, Holding Jigs, And Positioning Jigs (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)
  • Inorganic Insulating Materials (AREA)
  • Organic Insulating Materials (AREA)
  • Shaping Of Tube Ends By Bending Or Straightening (AREA)
  • Treatments Of Macromolecular Shaped Articles (AREA)
  • Clamps And Clips (AREA)

Claims (6)

1. Verfahren zur Befestigung einer schmiedbaren metallischen Hülse (3) auf einem Stab (10) aus Verbundmaterial, wobei die Hülse einen zylindrischen Innenraum (6) aufweist, in den ein Ende (11) des Stabs eingeführt ist und wobei man einen Kompressionsvorgang durchführt, der zu einer Längung der Hülse führt, dadurch gekennzeichnet, daß der Kompressionsvorgang in kontinuierlicher Weise mithilfe von Werkzeugen durchgeführt wird, deren Punkte radialen Kontakts mit der Hülse (3) gleichmäßig über einen Ringbereich der Hülse verteilt sind und sich im wesentlichen vom Eingang der Hülse bis im wesentlichen zum Ende des Stabs (10) bewegen, um so das Metall der Hülse um den Stab herum zu verformen, ohne das Verbundmaterial über seine Grenze der elastischen Längung hinaus zu dehnen.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß die Kompressionskraft gemäß den betroffenen Ringbereichen variabel ist.
3. Elektrischer Isolator mit einem Stab (10) aus Verbundmaterial und mindestens einer Armatur (2) mit einer Hüise (3), dadurch gekennzeichnet, daß der Stab in der Hülse durch das Verfahren nach einem der Ansprüche 1 und 2 befestigt wird.
4. Elektrischer Isolator nach Anspruch 3, dadurch gekennzeichnet, daß der Eingang der Hülse einen Wulst (5) aufweist, der nicht auf den Stab (10) komprimiert wird.
5. Elektrischer Isolator nach Anspruch 3, dadurch gekennzeichnet, daß das Metall der Hülse (3) aus Stahl, einer Aluminiumlegierung oder einer Aluminiumbronze ist.
6. Elektrischer Isolator nach Anspruch 3, dadurch gekennzeichnet, daß das Verbundmaterial aus mit einem synthetischen Harz imprägnierten Glasfasern besteht.
EP84101546A 1983-02-22 1984-02-16 Verfahren zur Befestigung einer schmiedbaren Metallhülse auf einem Stab aus Verbundmaterial und durch die Ausführung dieses Verfahrens erhaltener Isolator Expired EP0119467B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84101546T ATE25166T1 (de) 1983-02-22 1984-02-16 Verfahren zur befestigung einer schmiedbaren metallhuelse auf einem stab aus verbundmaterial und durch die ausfuehrung dieses verfahrens erhaltener isolator.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8302853 1983-02-22
FR8302853A FR2541501B1 (fr) 1983-02-22 1983-02-22 Procede pour fixer un manchon metallique malleable sur un jonc en materiau composite

Publications (2)

Publication Number Publication Date
EP0119467A1 EP0119467A1 (de) 1984-09-26
EP0119467B1 true EP0119467B1 (de) 1987-01-21

Family

ID=9286150

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84101546A Expired EP0119467B1 (de) 1983-02-22 1984-02-16 Verfahren zur Befestigung einer schmiedbaren Metallhülse auf einem Stab aus Verbundmaterial und durch die Ausführung dieses Verfahrens erhaltener Isolator

Country Status (14)

Country Link
US (1) US4656720A (de)
EP (1) EP0119467B1 (de)
JP (1) JPS59163035A (de)
AT (1) ATE25166T1 (de)
AU (1) AU569867B2 (de)
BR (1) BR8400786A (de)
CA (1) CA1264531A (de)
DE (1) DE3462197D1 (de)
ES (1) ES8501564A1 (de)
FR (1) FR2541501B1 (de)
MX (1) MX159352A (de)
NO (1) NO164565C (de)
NZ (1) NZ207222A (de)
ZA (1) ZA841263B (de)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2604821B1 (fr) * 1986-10-02 1990-01-12 Ceraver Isolateur composite a revetement isolant surmoule
US5233132A (en) * 1986-10-02 1993-08-03 Sediver Societe Europeenne D'isolateurs En Composite insulator comprising a fiber-resin rod and an insulating coating molded thereover
US6544286B1 (en) * 2000-07-18 2003-04-08 Tissue Engineering Refraction, Inc. Pre-fabricated corneal tissue lens method of corneal overlay to correct vision
GB0414131D0 (en) 2004-06-24 2004-07-28 Tyco Electronics Raychem Irela A method of manufacturing a crimped assembly, and related apparatuses
CN103639652B (zh) * 2013-11-26 2016-03-16 常熟市福熙机械零部件制造有限公司 耐高温紧固件的生产工艺

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE495241C (de) * 1927-08-17 1930-04-04 Reinhold Pfundt Verfahren zum Befestigen von Beschlaegeteilen an Isolierkoerpern
DE909954C (de) * 1939-12-07 1954-04-26 Aeg Vorrichtung zur Befestigung von Beschlaegeteilen an Isolierkoerpern
DE1400003A1 (de) * 1956-05-07 1968-10-10 British Insulated Callenders Verfahren zum Herstellen einer zugfesten Verbindung zwischen einer Metallarmatur undeinem glatten zylindrischen Stab oder Rohr aus glasfaserverstaerktem synthetischen Werkstoff
GB816926A (en) * 1956-05-07 1959-07-22 British Insulated Callenders Method of attaching fittings to rods or tubes of resin-bonded fibre and fittings attached to such rods or tubes
FR1241157A (fr) * 1959-07-21 1960-09-16 Grands Travaux De Marseille Sa Procédé et appareil pour la réalisation de têtes d'ancrage sur un câble tendu ou non, ou sur une barre
US3549790A (en) * 1969-03-27 1970-12-22 Anderson Electric Corp Strain insulator
JPS5633538B2 (de) * 1974-03-25 1981-08-04
JPS5286968A (en) * 1976-01-14 1977-07-20 Fuji Machine Mfg Method and device for making turnbuckle body
JPS5411337A (en) * 1977-06-24 1979-01-27 Koromensukii Zabuodo Tekusuchi Permanent connection bitween parts of pipe stopper mold
JPS6054730B2 (ja) * 1978-03-02 1985-12-02 日本碍子株式会社 合成樹脂碍子
JPS5598418A (en) * 1979-01-20 1980-07-26 Ngk Insulators Ltd Synthetic resin insulator

Also Published As

Publication number Publication date
CA1264531A (fr) 1990-01-23
JPS59163035A (ja) 1984-09-14
EP0119467A1 (de) 1984-09-26
AU2477084A (en) 1984-08-30
NO164565C (no) 1990-10-17
AU569867B2 (en) 1988-02-25
DE3462197D1 (en) 1987-02-26
NZ207222A (en) 1987-02-20
JPH021570B2 (de) 1990-01-12
NO840618L (no) 1984-08-23
FR2541501B1 (fr) 1985-08-02
MX159352A (es) 1989-05-17
NO164565B (no) 1990-07-09
ATE25166T1 (de) 1987-02-15
FR2541501A1 (fr) 1984-08-24
ES529922A0 (es) 1984-11-16
US4656720A (en) 1987-04-14
BR8400786A (pt) 1984-09-25
ES8501564A1 (es) 1984-11-16
ZA841263B (en) 1984-09-26

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