Linchpin

Last updated
Wagon wheel, with forged linchpin A aesthetic linchpin.JPG
Wagon wheel, with forged linchpin
A modern linchpin with an integral spring retainer Lynch-pin.jpg
A modern linchpin with an integral spring retainer

A linchpin, also spelled linch pin, lynchpin, or lynch pin, is a fastener used to prevent a wheel or other part from sliding off the axle upon which it is riding. The word is first attested in the late fourteenth century and derives from Middle English elements meaning "axletree pin". [1] [2]

Contents

Securing implements onto the three-point hitch of a tractor is an example of application. Linchpins may also be used in place of an R-clip for securing hitch pins. [3]

Metaphorical use

The word "linchpin" is also used figuratively to mean "something [or someone] that holds the various elements of a complicated structure together". [4]

See also

Related Research Articles

<span class="mw-page-title-main">Wrench</span> Tool used to provide grip and mechanical advantage

A wrench or spanner is a tool used to provide grip and mechanical advantage in applying torque to turn objects—usually rotary fasteners, such as nuts and bolts—or keep them from turning.

<span class="mw-page-title-main">Shackle</span> Metal assembly which functions as a removable connecting link

A shackle, also known as a gyve, is a U-shaped piece of metal secured with a clevis pin or bolt across the opening, or a hinged metal loop secured with a quick-release locking pin mechanism. The term also applies to handcuffs and other similarly conceived restraint devices that function in a similar manner. Shackles are the primary connecting link in all manner of rigging systems, from boats and ships to industrial crane rigging, as they allow different rigging subsets to be connected or disconnected quickly.

<span class="mw-page-title-main">Stapler</span> Tool used to fasten paper or flesh together

A stapler is a mechanical device that joins pages of paper or similar material by driving a thin metal staple through the sheets and folding the ends. Staplers are widely used in government, business, offices, workplaces, homes, and schools.

<span class="mw-page-title-main">Fastener</span> Hardware device that mechanically joins or affixes two or more objects together

A fastener or fastening is a hardware device that mechanically joins or affixes two or more objects together. In general, fasteners are used to create non-permanent joints; that is, joints that can be removed or dismantled without damaging the joining components. Steel fasteners are usually made of stainless steel, carbon steel, or alloy steel.

<span class="mw-page-title-main">Clevis fastener</span> Fastener consisting of a U-shaped bracket through which a pin is placed

A clevis fastener is a two-piece fastener system consisting of a clevis and a clevis pin head.

<span class="mw-page-title-main">Split pin</span> Metal fastener with two tines that are bent during installation

A split pin, also known as a cotter pin, or cotter key in the US, is a metal fastener with two tines that are bent during installation, similar to a staple or rivet. Typically made of thick wire with a half-circular cross section, split pins come in multiple sizes and types.

<span class="mw-page-title-main">Safety wire</span> Locking device for bolts etc.

A safety wire or locking-wire is a type of positive locking device that prevents fasteners from falling out due to vibration and other forces. The presence of safety wiring may also serve to indicate that the fasteners have been properly tightened.

<span class="mw-page-title-main">Nail gun</span> Type of power tool

A nail gun, nailgun or nailer is a form of hammer used to drive nails into wood or other materials. It is usually driven by compressed air (pneumatic), electromagnetism, highly flammable gases such as butane or propane, or, for powder-actuated tools, a small explosive charge. Nail guns have in many ways replaced hammers as tools of choice among builders.

<span class="mw-page-title-main">Pintle</span> Pin or bolt used as part of a pivot or hinge

A pintle is a pin or bolt, usually inserted into a gudgeon, which is used as part of a pivot or hinge. Other applications include pintle and lunette ring for towing, and pintle pins securing casters in furniture.

<span class="mw-page-title-main">Castellated nut</span> A nut with slots cut into one end

A castellated nut, sometimes referred to as a castle nut, is a nut with slots or notches cut into one end. The name comes from the nut's resemblance to the crenellated parapet of a medieval castle. Castellated nuts are sometimes incorrectly referred to as castigated nuts.

<span class="mw-page-title-main">Circlip</span> Type of fastener or retaining ring

A circlip, also known as a C-clip, snap ring, or ', is a type of fastener or retaining ring that consists of a semi-flexible metal ring with open ends that can be snapped into place into a machined groove on a dowel pin or other part to permit rotation but to prevent axial movement. There are two basic types of circlips: internal and external. Circlips are used to secure pinned connections.

<span class="mw-page-title-main">Cotter (pin)</span> Pin or wedge passing through a hole to fix parts tightly together

A cotter is a pin or wedge with a flat bearing surface passing through a hole to fix parts tightly together. In British usage cotter pin has the same meaning, but in the U.S. it means a split pin.

<span class="mw-page-title-main">Bezel (jewellery)</span> Section on the hoop of a ring

A bezel is a wider and usually thicker section of the hoop of a ring, which may contain a gem or a flat surface. Rings are normally worn to display bezels on the upper or outer side of the finger. In gem-cutting the term bezel is used for those sloping facets of a cut stone that surround the flat table face, which is the large, horizontal facet on the top.

<span class="mw-page-title-main">R-clip</span> Type of fastener made of a springy material

An R-clip, also known as an R-pin, R-key, hairpin cotter pin, hairpin cotter, bridge pin, hitch pin clip or spring cotter pin, is a fastener made of a durable but flexible material, commonly hardened metal wire, resembling the shape of the letter "R".

<span class="mw-page-title-main">Spring pin</span> Mechanical fastener that secures the position of two or more parts relative to each other

A spring pin is a mechanical fastener that secures the position of two or more parts of a machine relative to each other. Spring pins have a body diameter which is larger than the diameter of the hole they are intended for, and a chamfer on either one or both ends to facilitate starting the pin into the hole. The spring action of the pin allows it to compress as it assumes the diameter of the hole. The force exerted by the pin against the hole wall retains it in the hole, therefore a spring pin is considered a self retaining fastener.

Cotter pin may refer to:

<span class="mw-page-title-main">Circle cotter</span> Ring type of retaining component

A circle cotter, also known as a cotter ring or split ring, is a formed wire fastener that is shaped like a circle, hence the name. The open end of the wire is in the middle of the cotter so when it is installed the inner tab is first installed in the hole. Because of this feature it is often used in applications where a sharp edge cannot be tolerated, such as fabric applications.

<span class="mw-page-title-main">Machine element</span> Elementary components used in the structure, controls, or mechanisms of a machine

Machine element or hardware refers to an elementary component of a machine. These elements consist of three basic types:

  1. structural components such as frame members, bearings, axles, splines, fasteners, seals, and lubricants,
  2. mechanisms that control movement in various ways such as gear trains, belt or chain drives, linkages, cam and follower systems, including brakes and clutches, and
  3. control components such as buttons, switches, indicators, sensors, actuators and computer controllers.
<span class="mw-page-title-main">Positive locking device</span>

A positive locking device is a device used in conjunction with a fastener in order to positively lock the fastener. This means that the fastener cannot work loose from vibrations. The following is a list of positive locking devices:

7-122. GENERAL. The word safetying is a term universally used in the aircraft industry. Briefly, safetying is defined as: "Securing by various means any nut, bolt, turnbuckle etc., on the aircraft so that vibration will not cause it to loosen during operation." These practices are not a means of obtaining or maintaining torque, rather a safety device to prevent the disengagement of screws, nuts, bolts, snap rings, oil caps, drain cocks, valves, and parts. Three basic methods are used in safetying; safety-wire, cotter pins, and self-locking nuts. Retainer washers and pal nuts are also sometimes used.

7-124d. Safety wire must be installed in a manner that will prevent the tendency of the part to loosen.

References

  1. linch-pin, n..OED Online. June 2014. Oxford University Press. (accessed December 21, 2024; original link now behind paywall).
  2. linchpin (n.). Online Etymology Dictionary. (accessed 1 June 2018).
  3. "Hitch Pins and Linch Pins Information on GlobalSpec". Archived from the original on 2010-08-18.
  4. "Linchpin". Dictionary.reference.com. Retrieved 2012-03-24.