Editing Electrical connector (section)

===Hyperboloid contacts===
To deliver ensured signal stability in extreme environments, traditional pin and socket design may become inadequate. Hyperboloid contacts are designed to withstand more extreme physical demands, such as vibration and shock.<ref name="nykcs-circular">{{cite web |url=https://www.nykcs.com/circular-connector-terminology-guide/ |title=Circular Connector Terminology Guide |website=NYK Component Solutions |last1=Worley |first1=Jon |date=31 July 2018 |access-date=2018-10-15}}</ref> They also require around 40% less insertion force<ref name="hyperboloid-connsupp" />{{snd}} as low as {{convert|0.3|N|oz-f|0}} per contact,<ref name="ieh-catalog">{{cite web |url=https://www.iehcorp.com/_uploads/pdf/catalogs/hgm.pdf |title=IEH Hyperboloid Connectors |website=IEH Corporation |date=October 2017 |access-date=27 June 2019}}</ref>{{snd}}which extends the lifespan, and in some cases offers an alternative to [[zero insertion force]] connectors.<ref name="ieh-hyperboloid">{{cite web |url=https://www.iehcorp.com/about/technology/ |website=IEH Corporation |title=Our Technology |access-date=26 June 2019}}</ref><ref name="hyperboloid-connsupp">{{cite web |url=https://www.connectorsupplier.com/modern-hyperboloid-contacts-for-circular-io-connectors/ |title=Modern Hyperboloid Contacts for Circular I/O Connectors |date=8 June 2015 |last1=Lascelles |first1=Robert |website=ConnectorSupplier.com |access-date=27 June 2019}}</ref>

In a connector with hyperboloid contacts, each female contact has several equally spaced longitudinal wires twisted into a hyperbolic shape. These wires are highly resilient to strain, but still somewhat elastic, hence they essentially function as linear springs.<ref name="hyperboloid-connector-tips">{{cite web |url=https://www.connectortips.com/would-you-trust-your-life-to-a-50-year-old-connector-design/ |title=Would you trust your life to a 50-year old connector design? |author=David Brearley |date=9 October 2015 |website=Connector Tips |access-date=27 June 2019}}</ref><ref name="hyperboloid-su-patent">{{cite patent |country=SU |number=1125684A1 |status=application |title=Hyperboloid-shaped socket for connection device |invent1=Pustynskij Nikolaj |pubdate=1983 |url=https://patents.google.com/patent/SU1125684A1}}.</ref> As the male pin is inserted, axial wires in the socket half are deflected, wrapping themselves around the pin to provide a number of contact points. The internal wires that form the hyperboloid structure are usually anchored at each end by bending the tip into a groove or notch in the housing.<ref name="hyperboloid-uk-patent">{{cite patent |country=GB |publication-number=2366097A |status=application |title=Hyperboloid electrical socket |pubdate=27 February 2002 |invent1=Donald Richard Lacoy |url=https://patents.google.com/patent/US6464546B2}}.</ref>

Whilst hyperboloid contacts may be the only option to make a reliable connection in some circumstances, they have the disadvantage of taking up greater volume in a connector, which can cause problems for high-density connectors.<ref name="hyperboloid-connsupp" /> They are also significantly more expensive than traditional pin and socket contacts, which has limited their uptake since their invention in the 1920s by Wilhelm Harold Frederick.<ref name="hyperboloid-us-patent">{{cite patent |country=US |publication-number=1833145A |status=patent |title=Connecter |pubdate=7 July 1925 |invent1=Wilhelm Harold Frederick |url=https://patents.google.com/patent/US1833145A}}.</ref> In the 1950s, Francois Bonhomme popularised hyperboloid contacts with his "Hypertac" connector, which was later acquired by [[Smiths Group]]. During the following decades, the connectors steadily gained popularity, and are still used for medical, industrial, military, aerospace, and rail applications (particularly trains in Europe).<ref name="hyperboloid-connector-tips" />