US Patent 7281295 Canister vacuum cleaner with stair hugging swivel wheel assembly

A canister vacuum cleaner has a canister assembly and a stair hugging swivel wheel assembly. The stair hugging swivel wheel assembly pivotally connects to the canister assembly and has both a pendulum and a wheel rotatably mounted to a housing thereof. During use, the pendulum projects from the housing under the influence of gravity to inhibit or otherwise prevent the stair hugging swivel wheel assembly from pivoting whenever the canister assembly becomes oriented in an inclined position, such as when placed on a stairway. Preferably, the pendulum mates with a recess in the canister assembly co-located with a circular track in which the stair hugging swivel wheel assembly pivots.