A device (10) is disclosed for providing air to a tire which is mounted on a wheel rim which itself is free to rotate about a fixed, that is, non-rotatable axle 22. The device includes a pump (50, 52, 54, 62) which in use rotates with the tire and which is configured to provide, when activated, air under pressure to the tire. There is a pump drive system for activating the pump. The pump drive system comprising a piston rod (56) which is connected to and rotates with the tire and a body (40) which rotates in unison with the rod (56) while the pump is inactive. An electric motor (68) rotates the body (40) with respect to the rod (56) to activate the pump and provide air to the tire. Rotation of the body (40) is superimposed on rotation of the pump with the tire. The device also includes a stator component (26) and coils (30) and magnets (32) for generating, by electrical induction, power for driving the motor using the relative rotation between the second part and the stator component (26).

A pumping assembly for maintaining a pneumatic tires inflation pressure is described. The pumping assembly includes at least one double chamber pump connected to a cam. The cam is connected to a gravity mass to maintain the cam in a stationary position. The pump has a roller for engaging the cam and producing the pumping action as the tire rim rotates. The assembly is preferably mounted in a reservoir wherein the reservoir is in fluid communication with one or more tire cavities. The system requires no alteration to the tire and pumps the air directly into the valve stem. The pumps are configured to provide an amplication effect because of the way they are configured, and thus do not need high compression ratios.

An air maintenance tire pump simulator that simulates the environment of an air maintenance tire system is provided. The simulator includes at least one pneumatic cylinder, a structure that forms a closed cavity, and a pneumatic conduit extending between and fluidly connecting the pneumatic cylinder and the closed cavity. A cam is operably connected to a motor, and is also operably connected to the pneumatic cylinder. Engagement of the motor actuates rotation of the cam, which in turn actuates operation of the pneumatic cylinder to increase a pressure in the closed cavity. A method of simulating an air maintenance tire system is also provided.

A system for tire inflation including a drive mechanism defining a rotational axis, including an eccentric mass that offsets a center of mass of the drive mechanism from the rotational axis along a radial vector; a pump arranged radially distal the rotational axis of the drive mechanism, including a chamber defining a chamber lumen, and a reciprocating element arranged at least partially within the chamber lumen and translatable along a pump axis; a drive coupler coupled between the drive mechanism at a first position and the reciprocating element at a second position fixed to the reciprocating element; a torque regulation mechanism; and a controller, communicatively coupled to the torque regulation mechanism; wherein the system is operable between at least a first mode and a second mode by the torque regulation mechanism in cooperation with the controller.

A device for Controlling pressure is disclosed which comprises a pump (28) having opposed pistons (30) which reciprocate in cylinders (40) carried by a casing (38). The pistons (30) are at the outer ends of rings (50) which are themselves fitted to an eccentric (26). The eccentric (28) is integral with a clutch plate (24). A second clutch plate (22) is fixed to a non-rotating axle (18) which itself forms part of a hanging counterweight structure (20). A piston (84) pushes the eccentric and clutch plate (26, 24) against the clutch plate (22) thereby to prevent the eccentric (26) tire from rotating with the rings (50) upon a sensor detecting that a tire has a low pressure in it. Stopping the eccentric initiates the pumping action of the pistons (30).

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 system configured to pump fluid from the ambient environment to a target reservoir, the pumping system including: a fluid pump configured to statically mount to a rotating surface, the pump configured to rotate about an axis of rotation; a pump reservoir statically coupled to the fluid pump and configured to fluidly couple to the target reservoir, the pump reservoir including a collection area defined along a portion of the pump reservoir radially outward of the axis of rotation; and a liquid separation member arranged along a portion of the collection area, the liquid separation member including a membrane configured to preferentially permit liquid flow therethrough.

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.

A tire inflation system and method for a tire supported by a wheel, the tire inflation system including a pump system including a pump cavity configured to fluidly connect to the tire, an actuating element configured to actuate relative the pump cavity, a drive mechanism rotatably coupled to the wheel, the drive mechanism including a motion transformer and an eccentric mass, a valve fluidly connecting the pump cavity to a fluid reservoir; and a control system configured to operate the valve.

In variants, a two-stage pump can include a piston and a cylinder cooperatively defining a first stage in front of the piston fluidly connected to a second stage behind the piston, wherein a forward stroke of the piston pressurizes working fluid in the first stage and forces pressurized working fluid into the second stage, and a backward stroke of the piston further pressurizes working fluid in the second stage and exhausts pressurized working fluid out a pump exhaust.