Content deleted Content added
No edit summary Tags: Reverted missing file added Mobile edit Mobile web edit |
Removing Heavy-duty-trolley-castors-wheels-cator-wheel-exporter.png; it has been deleted from Commons by EugeneZelenko because: c:Commons:Licensing: adv |
||
| (14 intermediate revisions by 13 users not shown) | |||
Line 2:
{{Other uses}}
[[File:Swivel
A '''caster''' (or '''castor''') is an undriven [[wheel]] that is designed to be attached to the bottom of a larger object (the "vehicle") to enable that object to be moved.
==Types==
[[File:Löffelholz-Codex Ms-Berol-Germ-Qu-132 Fol 010v.png|thumb|Drawing of a swivelling caster from Codex Löffelholz, Nuremberg 1505]]
Casters may be fixed to roll along a straight line path, or mounted on a [[wiktionary:Pivot|pivot]] or [[pintle]] such that the wheel will automatically align itself to the direction of travel.
===Rigid casters===
A basic, rigid caster consists of a wheel mounted to a stationary fork. The orientation of the fork, which is fixed relative to the vehicle, is determined when the caster is mounted to the vehicle.<ref>{{Cite book |last=Wagner |first=Markus |url=https://books.google.com/books?id=HkoRC4_vR1IC&pg=PA557 |title=VERZEICHNIS MECHATRONIK: Grundlagen-BEGRIFFE werden erklaert - in German language: alphabetical index of technical terms mechatronics |date=2015-05-19 |publisher=LEHRMITTEL WAGNER / Autor |isbn=978-3-86479-138-3 |language=de}}</ref> An example of this is the wheels found at the rear of a shopping cart in North America. Rigid casters tend to restrict vehicle motion so that the vehicle travels along a straight line.
===Swivel casters===
[[Image:Caster-wheels-chair.jpg|thumb|left|upright|Two wheeled swivel casters on a [[desk chair]] (no fork)]]
Like the simpler rigid caster, a swivel caster incorporates a wheel mounted to a fork, but an additional [[swivel joint]] above the fork allows the fork to freely rotate about 360°, thus enabling the wheel to roll in any direction. This makes it possible to easily move the vehicle in any direction without changing its orientation. Swivel casters are sometimes attached to handles so that an operator can manually set their orientation. The improved swivel caster was invented in 1920 by Seibert Chesnutt, US Patent 1341630, which was easily manufactured by stamping, and incorporated ball bearings for longer life. Basic swivel casters were in evidence in Charles Darwin's famous "office chair" as early as the 1840s.
Line 43 ⟶ 44:
=== Kingpinless casters ===
A Kingpinless caster has an inner raceway, an outer raceway which is attached to the vehicle, and ball bearings between the raceways. This mechanism has no [[kingpin (automotive part)|kingpin]], hence the name kingpinless. The absence of a kingpin eliminates most causes of swivel caster failure{{citation needed|date=February 2016}} and reduces or eliminates shimmy
== Caster flutter ==
| |||
