How to reduce rope hoist broken tooth

Forms of  rope hoist gear failure "broken tooth" and how to reduce the incidence of gear cut, summarize the following for your reference:
        Rope hoist  teeth like a cantilever under load to the tooth root bending stress generated by the largest and is alternating stress. When the gear loaded on one side, the stress changes by pulsation cycle; when the tooth sides under load, the stress cycle by symmetrical changes. Change gear by repeated bending stress the role of the tooth root stress concentration transition portion, when the stress exceeds the bending fatigue limit of the material, the tooth root fatigue crack, resulting in tooth fracture crack gradually extended. This break is called fatigue fracture. When the  rope hoist gear suddenly overloaded or worn by severe tooth thickness is too thin, it will also occur tooth broken, called overload broken. If the tooth width is too large, due to manufacturing and installation to the local error under load is too large, it will cause local break. In helical gears, the tooth working surface of the contact line is a slash, the teeth under load if load concentration occurs when the local break. If the bending deformation of the shaft caused by excessive localized tooth under load is too large, also the occurrence of local breaking.
Improve anti-fracture capacity   wire rope hoist  gear measures many, such as increasing the tooth root fillet radius to eliminate machining marks where the tooth root to reduce the stress concentration; increases the stiffness of the shaft and support materials to reduce tooth local overload extent; shot peening of teeth, cold rolling and other tooth surface processing to improve the hardness, toughness, etc. to keep the core portion.