BOOM CRANE OVERLOAD SAFEGUARD Russian patent published in 1995 - IPC

FIELD: mechanical engineering; boom cranes. SUBSTANCE: boom crane overload safeguard has body, directing and deflecting rollers and load lifting wire rope passed over rollers. One end of wire rope is secured in lock. Overload safeguard has also limit switch, double-arm lever with counterweight mounted on longer arm and end of shorter arm hinge-connected to overload safeguard body. Overload safeguard operates as follows. With crane boom with fitted on overload safeguard being raised from horizontal position into extreme upper position, moment built owing to cantilever arrangement of counterweight on lever longer arm increases causing deflection of load-lifting wire rope through double-arm lever and hinge-mounted deflecting roller. To make overload safeguard operate, load on hook which causes straightening of wire rope should also increase. EFFECT: enlarged operating capabilities. 1 dwg