Wear and overload signal system for charger hoists e.g. for concrete - activates warning signal or switches from drive system with overload or wear of carrying rope and prevents fall of hoist bucket

摘要

A second rope drum (8) turns in synchronism with the first known drum (5), on which a safety rope (9) is wound running in the same direction as the carrying rope (6). The safety rope runs parallel to the carrying rope across a second rope pulley (10) at the charger bucket (1) and is suspended at its free end to a spring loaded suspension bolt (11) or is fixed directly at the charger. The safety rope, in conjunction with the spring coupled at its free end, has a softer spring characteristic than the carrying rope, or the safety rope in conjunction with a spring mounted deflection has a softer spring characteristic than the carrying rope, which is fitted outside the charger bucket travel range with at least one sensor. The sensor monitors the movements of the safety rope or the spring for unpermitted wear, namely, with overloading of the load rope activates a warning signal or the switching off of the drive. ADVANTAGE - Protects against overload or wear of rope and overcomes disadvantages by also preventing drop of bucket, tipping or sticking fast, when bucket is travelling upwards.