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Summary
DescriptionPentaspastos scheme.svg
Deutsch: Darstellung eines römischen Pentaspastos-Krans. Der Pentaspastos ("5-Rollen-Zug") stellte einen mittelgroßen römischen Krantyp dar. Er bestand aus Hebebaum, zwei Haspeln, einem Seil und einem Flaschenzug mit fünf Rollen. Dies entspricht einer Übersetzung von 5 zu 1. Die zwei Arbeiter an der Haspel konnten - unter der Annahme, dass 50 kg den maximalen Krafteinsatz darstellen, den ein Mann über einen längeren Zeitraum ausüben kann - Lasten von ca. 450 kg heben.
English: Scheme of an ancient Roman Pentaspastoscrane ("Five-pulley-crane"). Being a medium-sized Roman crane, the Pentaspastos consisted of a single-beam jib, two winches, a rope, and a block containing five pulleys. Having thus a mechanical advantage of 5:1, the two men working the winch could raise loads of ca. 450 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 pentaspastos utilisant cinq 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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Trispastos-type crane
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