TROLLEY

摘要

A novel crane trolley has four guiding pulleys lying on opposed upper and lower guiding surfaces, arranged diagonally to eliminate the need for having eight guiding pulleys. On each side of the trolley are upper and lower guiding pulleys, with the lower in front on one side and the upper in front on the other side. The pulleys may be mounted under spring tension. Two such trolleys may be hinged together to support heavy loads.