Abstract: Embodiments of this document provides improved safety logic for a mobile container handler of the reach stacker or top pick type. The improved logic involves limitations surrounding the hoist function of the machine subsequent to attaching to a shipping container. This improvement addresses damage to the container spreader caused by abrupt joystick hoist inputs by the operator immediately subsequent to attaching onto a shipping container. Due to space between the spreader arms and spreader body, which is so designed to facilitate movement of the arms inside the spreader body, sudden vertical movement of the spreader results in impact forces being exerted on various parts of the spreader body and spreader arms. These impacts accelerate fatigue leading to premature catastrophic failure of the spreader body and/or spreader arms' structural steel.

Abstract: Embodiments of this document provides improved safety logic for a mobile container handler of the reach stacker or top pick type. The improved logic involves limitations surrounding the hoist function of the machine subsequent to attaching to a shipping container. This improvement addresses damage to the container spreader caused by abrupt joystick hoist inputs by the operator immediately subsequent to attaching onto a shipping container. Due to space between the spreader arms and spreader body, which is so designed to facilitate movement of the arms inside the spreader body, sudden vertical movement of the spreader results in impact forces being exerted on various parts of the spreader body and spreader arms. These impacts accelerate fatigue leading to premature catastrophic failure of the spreader body and/or spreader arms' structural steel.