US Patent 9297454 Gear unit with improved lubricant supply

In order to implement a reliable supply of lubricant to gear unit components during emergency or spinning operation of a gear unit, level control is provided in a lubricant sump of the gear unit as a function of the operating state by means of a control unit associated with a lubricant pump. During normal operation the level is adjusted to dry sump level. In contrast, the lubricant pump is switched off in emergency or spinning operation, so that a splash lubrication level is automatically achieved in the lubricant sump.