An air maintenance system for use with a pneumatic tire is described. The air maintenance system includes a pumping mechanism that is preferably mounted on the interior surface of a wheel rim to keep the pneumatic tire from becoming underinflated. The pumping mechanism includes at least one dual chamber pump, preferably at least two dual chamber pumps configured in series. More preferably, the dual chamber pumps are driven by an external mass that moves as the tire rotates. The tire's rotational energy operates the pump to ensure the tire cavity is maintained at the desired pressure level. An optional control valve shuts off airflow to the pumping mechanism when the tire cavity pressure is at the desired level.

The present invention relates generally to an air maintenance system for use with a tire and, more specifically, to an air maintenance pumping assembly

A tire air filling device according to one embodiment includes a cylinder having a first opening communicating with a tire; and a weight that is provided inside the cylinder, that has an air flow hole through which air to be supplied to the tire passes, and that moves in an axial direction of the cylinder upon a receipt of a centrifugal force, to supply the air from the first opening to the tire. The tire air filling device includes a weight spring interposed between the weight and an inner surface of the cylinder; and an inclined member attached to a check valve that prevents a backflow of the air from the tire to an inside of the cylinder, and to the cylinder in a state where the cylinder is inclined with respect to the check valve.

A system is used with a pneumatic tire mounted on a wheel rim to keep the pneumatic tire from becoming underinflated. The first system includes a plurality of pumps attached circumferentially to the wheel rim, each pump having pump parameters, and a control valve for controlling inlet air into a tire cavity of the pneumatic tire. The control valve has valve parameters. The system predicts system performance under various configurations and conditions through use of the pump parameters and the valve parameters.

A system is used with a pneumatic tire mounted on a wheel rim to keep the pneumatic tire from becoming underinflated. The first system includes a plurality of pumps attached circumferentially to the wheel rim, each pump having pump parameters, and a control valve for controlling inlet air into a tire cavity of the pneumatic tire. The control valve has valve parameters. The system predicts system performance under various configurations and conditions through use of the pump parameters and the valve parameters.

An air maintenance system includes a rotating inner ring associated with a vehicle wheel, a stationary outer ring maintaining a constant angular position, the stationary outer ring including ring segments secured together by a plurality of connecting shafts, an occlusion roller rotationally fixed to the stationary outer ring by a first connecting shaft of the plurality of connecting shafts, the occlusion roller having a protruding portion centered axially at a radially outer surface of the occlusion roller with axially outer portions of the occlusion roller being radially recessed from the protruding portion and supported by bearing surfaces of the rotating inner ring, spacer rollers rotationally fixed to the stationary outer ring by second and third connecting shafts of the plurality of connecting shafts and rotationally supported by the bearing surfaces, and a flexible tube defining a pump cavity, the air maintenance system pumping a fluid from the ambient environment into a pneumatic tire by applying an occluding force against the flexible tube, periodically occluding portions of the pump cavity. The spacer rollers have axially outer surfaces for rotational support by bearing surfaces of the rotating inner ring and a recess centered axially at the outer surface of the spacer rollers for avoiding any contact between the spacer rollers and the flexible tube.

An air maintenance system includes a rotating inner ring associated with a vehicle wheel, a stationary outer ring maintaining a constant angular position, the stationary outer ring including ring segments secured together by a plurality of connecting shafts, an occlusion roller rotationally fixed to the stationary outer ring by a first connecting shaft of the plurality of connecting shafts, the occlusion roller having a protruding portion centered axially at a radially outer surface of the occlusion roller with axially outer portions of the occlusion roller being radially recessed from the protruding portion and supported by bearing surfaces of the rotating inner ring, spacer rollers rotationally fixed to the stationary outer ring by second and third connecting shafts of the plurality of connecting shafts and rotationally supported by the bearing surfaces, and a flexible tube defining a pump cavity, the air maintenance system pumping a fluid from the ambient environment into a pneumatic tire by applying an occluding force against the flexible tube, periodically occluding portions of the pump cavity. The spacer rollers have axially outer surfaces for rotational support by bearing surfaces of the rotating inner ring and a recess centered axially at the outer surface of the spacer rollers for avoiding any contact between the spacer rollers and the flexible tube.

An air maintenance system includes a rotating inner ring secured to a vehicle wheel, a stationary outer ring maintaining a constant angular position, an occlusion roller rotationally fixed to the stationary outer ring, the occlusion roller having a protruding portion centered axially at a radially outer surface of the occlusion roller with axially outer portions of the occlusion roller being radially recessed from the protruding portion and supported by bearing surfaces of the rotating inner ring, spacer rollers rotationally fixed to the stationary outer ring and rotationally supported by the bearing surfaces, and a flexible tube defining a pump cavity, the air maintenance system pumping a fluid from the ambient environment into a pneumatic tire by applying an occluding force against the flexible tube, periodically occluding portions of the pump cavity. The spacer rollers have axially outer surfaces for rotational support by bearing surfaces of the rotating inner ring and a recess centered axially at the outer surface of the spacer rollers for avoiding any contact between the spacer rollers and the flexible tube.

An air maintenance system includes a rotating inner ring secured to a vehicle wheel, a stationary outer ring maintaining a constant angular position relative to a ground surface, a stationary mass secured to the stationary outer ring, a cylinder secured to the rotating inner ring, and a piston secured to the cylinder for linear motion relative to the cylinder and the rotating inner ring. The piston reciprocates axially back and forth as determined by a cam groove on an outer surface of the stationary outer ring operatively engaging one end of the piston such that the piston and cylinder pump air into a tire cavity of a pneumatic tire mounted to the vehicle wheel.

A pumping assembly keeps a pneumatic tire from becoming underinflated. The pumping assembly includes at least one pump attached to the tire rim, a cam fixed to the gravity mass for maintaining the cam in a fixed position relative to the gravity mass, and rollers for engaging the cam and producing the pumping action as the tire rim rotates and the gravity mass retards rotation of the cam.