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(11) | EP 0 090 549 B1 |
| (12) | EUROPEAN PATENT SPECIFICATION |
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| (54) |
Electrical contact assembly Zusammenbau eines elektrischen Kontaktes Assemblage d'un contact électrique |
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| Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). |
[0001] This invention relates to electrical connectors and more particularly to an electrical contact assembly for use in electrical connectors. A known type of electrical contacts are those that are formed as screw machine parts from bar stock. The bar stock from which these electrical contacts are machined has to be hard enough to enable them to be subjected to screw machine operations which can present problems when electrical conductors are crimped thereto due to the wire barrels breaking. These entire contacts are evenly gold plated thereover because they cannot be selectively gold plated. The insertion force when a pin is inserted thereinto is quite high.
[0002] Another type of known electrical contact assembly includes a screw machine wire barrel onto which is crimped a telescoped receptacle and hood. This type of contact can be selectively plated but a major drawback is aligning the receptacle and hood and simultaneously crimping them onto the wire barrel as properly aligned and concentric members. The wire barrel is a screw machine part and, due to its configuration, cannot be readily cold formed. The wire barrel would also be subject to breakage when crimped onto an electrical conductor because of the hardness of the metal if not subjected to annealing. The insertion force is not believed to be too low. Crimping of the receptacle onto the wire barrel does not provide a good mechanical and electrical connection and limits the diameter of the receptacle. The hood contains no beveled lead-in surface for the pin.
[0003] The present invention relates to an electrical contact assembly comprising a wire barrel onto which an electrical conductor is connected along with a receptacle contact member covered by a hood member. Examples are illustrated in FR-A-2 031 260 and BE-A-705 639. The invention is characterised in that the barrel member has a seamless bore at the forward end thereof, the receptacle contact member has a receptacle contact section and a securing section which is frictionally secured in the bore of the wire barrel and the hood member has an inner end crimped onto the wire barrel and covering the receptacle contact section. The hood has a beveled lead-in entrance to facilitate insertion of a pin contact member into electrical connection with the receptacle contact member at a substantially low insertion force.
Figure 1 is a perspective and exploded view of an electrical contact assembly.
Figure 2 is a perspective view of an assembled electrical contact assembly with an electrical pin contact exploded therefrom.
Figure 3 is a cross-sectional view of the assembled electrical contact assembly.
Figure 4 is a cross-sectional view taken along line 4-4 of Figure 1.
Figure 5 is a cross-sectional view taken along line 5-5 of Figure 3.
Figure 6 is a perspective view showing an electrical connector in which the electrical contact assemblies are mounted.
Figure 7 is a cross-sectional view showing the electrical contact assembly secured in an opening of the electrical connector.
[0004] Figures 1 through 5 illustrate the electrical contact assembly 10 of the present invention with Figure 6 showing an electrical connector EC in which the electrical contact assemblies are secured for matable connection with a similar electrical connector (not shown). Electrical contact assembly 10 includes a wire barrel 12, a receptacle contact member 14, and a hood member 16.
[0005] Wire barrel 12 can be a screw machine part or it can be made in accordance with cold-forming techniques in accordance with conventional practices. If wire barrel 12 is made as a screw machine part, copper alloy material is used, whereas if it is formed in accordance with cold-forming techniques, soft copper is used. It is preferable that soft copper be used so that wire barrel 12 can be cold-formed and it can be readily crimped onto electrical conductor 18.
[0006] Wire barrel 12 is provided with a bore 20 in which electrical conductor 18 is disposed for electrical connection therewith. A sight hole 22 is located in wire barrel 12 to make certain that electrical conductor 18 has been properly positioned within bore 20 prior to it being connected thereto. An annular shoulder 24 is located adjacent the front end of wire barrel 12 next to annular recess 26. A bore 28 extends inwardly from the front end of wire barrel 12.
[0007] Receptacle contact member 14 is a stamped and formed member that is preferably stamped from beryllium copper and includes a C-shaped section 30 which frictionally engages bore 28 of wire barrel 12 to form an excellent mechanical and electrical connection therewith thereby securing contact member 14 therewithin. The resilient characteristics of C-shaped section 30 adds to the retention characteristics of C-shaped section 30 in bore 28. Tapered channel-shaped section 32 extends between C-shaped section 30 and cylindrical section 34 and has arcuate-shaped contact-engaging members 36 extending outwardly therefrom which taper towards each other toward the front ends thereof. Contact member 14 is selectively plated in the electrical contact area only on the inside surfaces of contact-engaging members (36) with a heavy gold plating, and the rest of the contact member is flash plated. The selective gold plating can be done on the material before stamping and forming of contact member 14 takes place.
[0008] Hood member 16 is a stainless steel cylindrical member which has its inner end crimped into annular recess 26, whereas its front end has a beveled surface 38 for facilitating insertion of pin contact member 40 into electrical contact with receptacle contact member 14. Hood member 16 protects contact member 14 and prevents spring contact-engaging members 36 from being overstressed.
[0009] The electrical contact assembly of the present invention has a low insertion force because receptacle contact member 14 is a stamped and formed part. This is a significant factor when a large number of receptacle contact members are to be electrically connected with pin contact members. Another important factor is the saving that takes place on selective gold plating because only heavy gold plating takes place on the internal surfaces of contact-engaging members 36 whereas the rest of contact member 14 and wire barrel 12 are flash plated.
[0010] Figure 7 illustrates electrical contact assembly 10 secured in a passageway 42 in dielectric mounting block 44 of electrical connector EC by means of lances 46 of clip member 48 engaging shoulder 24 to prevent withdrawal of contact assembly 10. Shoulder 24 is limited in its inner movement within passageway 42 by surface 50 interposed between the larger and smaller diameter sections of passageways 42. Another dielectric block 52 abuts against block 44 and has a passageway 54 extending therethrough and in which part of the wire barrel of the contact assembly is disposed and along which part of electrical conductor 18 extends; the diameter of passageway 54 at the intersection between the passageways 42 and 54 is smaller in diameter than passageway 42 to maintain clip member 48 in passageway 42. An epoxy material or the like can be placed in passageway 54 to seal the wire barrel and its termination to conductor 18.
1. An electrical contact assembly (10) of the type including a wire barrel member
(12) to which an electrical conductor (18) is to be connected and a telescoped receptacle
contact member (14) and a hood member (16) secured onto the wire barrel member (12)
characterised in that said wire barrel member (12) has a seamless bore (28) at the
forward end thereof, said receptacle contact member (14) has a receptacle contact
section (34, 36) and a securing section (30) which is frictionally secured in the
bore (28) in said wire barrel member (12); and said hood member (16) has an inner
end crimped onto said wire barrel member (12) and covering said receptacle contact
section (34, 36).
2. An electrical contact assembly as set forth in claim 1 characterised in that said
securing section (30) is C-shaped.
3. An electrical contact assembly as set forth in claim 1 characterised in that said
receptacle section (34, 36) has arcuate-shaped contact-engaging members (36) tapering
toward each other toward the front end of said hood member (16).
4. An electrical contact assembly as set forth in claim 3 characterised in that said
receptacle section (34, 36) includes a tapered channel-shaped section (32) and a cylindrical
section (34) carrying said contact-engaging members (36).
5. An electrical contact assembly as set forth in claim 1 characterised in that said
hood member (16) has a bevelled inner surface (38) at a front end thereof.
1. Elektrische Kontaktanordnung (10) derjenigen Art, die ein Drahthülsenelement (12)
umfaßt, an dem ein elektrischer Leiter (18) anzuschließen ist, sowie ein teleskopisch
angeordnetes Buchsenkontaktelement (14) und ein auf dem Drahthülsenelement (12) festgelegtes
Haubenelement (16), dadurch gekennzeichnet, daß das Drahthülsenelement (12) eine nahtlose
Bohrung (28) an seinem vorderen Ende besitzt, daß das Buchsenkontaktelement (14) einen
Buchsenkontaktabschnitt (34, 36) und einen Befestigungsabschnitt (30) hat, der reibungsmäßig
in der Bohrung (28) in dem Drahthülsenelement (12) festgelegt ist, und daß das Haubenelement
(16) mit einem inneren Ende auf das Drahthülsenelement (12) gequetscht ist, und den
Buchsenkontaktabschnitt (34, 36) bedeckt.
2. Elektrische Kontaktanordnung nach Anspruch 1, dadurch gekennzeichnet, daß der der
Befestigungsabschnitt (30) C-förmig ist.
3. Elektrische Kontaktanordnung nach Anspruch 1, dadurch gekennzeichnet, daß der Buchsenabschnitt
(34, 36) bogenförmige Kontakteingriffselemente (36) hat, die aufeinanderzu zum Vorderende
des Haubenelements (16) hin verjüngt sind.
4. Elektrische Kontaktanordnung nach Anspruch 3, dadurch gekennzeichnet, daß der Buchsenabschnitt
(34, 36) einen verjüngten kanalförmigen Abschnitt (32) und einen zylindrischen Abschnitt
(34) umfaßt, welcher die Kontakteingriffselemente (36) trägt.
5. Elektrische Kontaktanordnung nach Anspruch 1, dadurch gekennzeichnet, daß das Haubenelement
(16) eine abgeschrägte innere Oberfläche (38) an ihrem Vorderende besitzt.
1. Assemblage (10) d'un contact électrique du type comprenant un élément de corps
(12) pour fil auquel un conducteur électrique (18) doit être connecté et un ensemble
télescopique d'un élément de contact femelle (14) et d'un élément à capuchon (16)
fixé sur l'élément de corps (12) pour fil, caractérisé en ce que ledit élément de
corps (12) pour fil présente un alésage (28) sans joint à son extrémité avant, ledit
élément de contact femelle (14) comporte un tronçon de contact femelle (34, 36) et
un tronçon de fixation (30) qui est fixé à frottement dans l'alésage (28) dudit élément
de corps (12) pour fil; et ledit élément à capuchon (16) présente une extrémité intérieure
sertie sur ledit élément de corps (12) pour fil et recouvrant ledit tronçon de contact
femelle (34, 36).
2. Assemblage d'un contact électrique selon la revendication 1, caractérisé en ce
que ledit tronçon de fixation (30) est de forme en C.
3. Assemblage d'un contact électrique selon la revendication 1, caractérisé en ce
que ledit tronçon femelle (34, 36) comporte des éléments (36) de forme incurvée, destinés
à porter contre un contact, se rapprochant l'un de l'autre vers l'extrémité avant
dudit élément à capuchon (16).
4. Assemblage d'un contact électrique selon la revendication 3, caractérisé en ce
que ledit tronçon femelle (34, 36) comporte un tronçon (32) en forme de profilé en
U conique et un tronçon cylindrique (34) portant lesdits éléments (36) destinés à
porter contre un contact.
5. Assemblage d'un contact électrique selon la revendication 1, caractérisé en ce
que ledit élément à capuchon (16) présente une surface intérieure chanfreinée (38)
à son extrémité avant.