Patent ID: 8820479

Claim:
A system for maintaining oil inside a gearbox at least at a minimum level when oil is not being pumped into the gearbox and an inclination of the gearbox causes oil to drain from the gearbox by gravity, the system comprising: (a) the gearbox; (b) an intermediate tank; (c) an external tank; (d) first means for connecting the intermediate tank with the gearbox so that oil exiting the gearbox enters the intermediate tank; (e) second means for connecting the intermediate tank with the gearbox to cause the intermediate tank and the gearbox to communicate with each other such that, when oil exiting the gearbox enters the intermediate tank and settles to a level that is below a maximum level in the intermediate tank, the oil will pass from the intermediate vessel into the gearbox until the oil is at the same level in the intermediate tank and the gearbox; and (f) third means for connecting the intermediate tank with the external tank such that, when oil from the gearbox enters the intermediate tank and settles to a level that is above the maximum level, oil will drain from the intermediate vessel into the external tank by gravity.