US Patent 9863445 Reservoir with draining compartment

A fluid reservoir comprises a first compartment, a second compartment, a port, a drain, and a tube. The port is fluidly connected to the first compartment and positioned at a port height. The drain is fluidly connected to the first compartment and the second compartment. An entrance to the drain is positioned in the first compartment at a drain entrance height which is lower than the port height. The tube is fluidly connected to the first compartment and the second compartment. An entrance to the tube is positioned in the first compartment at a tube entrance height which is higher than the drain height.