Blower impeller apparatus with one way valves

An impeller apparatus comprising:

• a plurality of blades;
• and
• a plurality of flexible flaps interleaved between the blades, wherein when the impeller has a rotational speed below a threshold range the flaps remain in a closed position substantially restricting air flow between the blades, wherein the flaps flex open to permit air flow between the blades when the rotational speed exceeds the threshold range.

An apparatus comprising:

• an impeller having a plurality of blades;
• and
• a hub comprising a plurality of valves, wherein the hub is disposed within an inner periphery such that the valves are interleaved between the blades, wherein the valves remain in a closed position substantially restricting air flow between the blades when the impeller has a rotational speed below a threshold range, wherein the valves open to permit air flow between the blades when the impeller speed exceeds the threshold range.

An apparatus comprising:

• an enclosure having at least one vent;
• and
• a plurality of blowers for exchanging air between the interior and the exterior of the enclosure in co-operation with the vent, wherein each blower comprises an impeller having a plurality of blades and a plurality of one way valves, wherein the one way valves are interleaved with the blades to substantially restrict reverse air flow through the blower when the rotational speed of the impeller falls below a threshold range.