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Summary
DescriptionTrispastos scheme.svg
Deutsch: Darstellung eines römischen Trispastos-Krans. Der Trispastos ("3-Rollen-Zug") stellte den einfachsten römischen Krantyp dar. Er bestand aus Hebebaum, einer Haspel, einem Seil und einem Flaschenzug mit drei Rollen. Dies entspricht einer Übersetzung von 3 zu 1. Ein einzelner Arbeiter an der Haspel konnte - unter der Annahme, dass 50 kg den maximalen Krafteinsatz darstellen, den ein Mann über einen längeren Zeitraum ausüben kann - Lasten von 150 kg heben (3 Rollen x 50 kg).
English: Scheme of an ancient Roman Trispastoscrane ("Three-pulley-crane"). Being the simplest Roman crane, the Trispastos consisted of a single-beam jib, a winch, a rope, and a block containing three pulleys. Having thus a mechanical advantage of 3:1, a single man working the winch could raise loads of 150 kg (3 pulleys x 50 kg), assuming that 50 kg represent the maximum effort a man can exert over a longer time period.
Français : Schéma d'une antique grue romaine du type trispastos utilisant trois poulies.
Date
Source
Own work
Based upon : Dienel, Hans-Liudger & Meighörner, Wolfgang: Der Tretradkran, Publication of the Deutsches Museum (Technikgeschichte Series), 2nd ed., München 1997, p.12f.
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Other versions
Pentaspastos-type crane
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