A pressure adjustment device for adjusting air pressure within a tire of a vehicle is disclosed. The device includes a housing formed of a cap and a base and including a piston, a spring and an air valve, wherein the cap includes an air inlet and the base includes an air outlet that is in fluid communication with the neck, wherein the piston moves proximally to compress the spring in response to a presence of a centrifugal force due to the vehicle traveling at least at a predetermined speed, where the proximal movement of the piston activates the air valve thereby enabling fluid to flow into the housing, and where the spring is configured to decompress when the centrifugal force decreases thereby deactivating the air valve and compressing the fluid within the housing distally out the air outlet toward the tire.

System for inflating a tire of a wheel, configured to be build inside or onto a hub of a vehicle, comprising a stationary section and a rotary section wherein the stationary section comprises a first clutch part, wherein the rotary section comprises a second clutch part, configured to selectively engage the first clutch part; an actuator, a driving unit, a pumping unit, and a housing, for housing at least the pumping unit, wherein the housing and the pumping unit are arranged to move together with movement of a wheel, in particular rotate together with the wheel.

A tire air filling device according to one embodiment includes: a cylinder; a weight which has an air flow hole and which receives a centrifugal force to move and cause air to be supplied to an inside of a tire; a first sealing member; a first spring; a first support portion; and a backflow prevention valve. The backflow prevention valve includes a slide member that slides in the air flow hole in an axial direction, a second spring that biases the slide member to a side opposite the tire, a second support portion that supports an end portion of the second spring in the axial direction; and a second sealing member interposed between an inner surface of the air flow hole and the slide member. The slide member, the second spring, and the second support portion are disposed inside the weight.

A self-inflation device for maintaining pressure in a tire includes a piston compartment, a piston, and an intake opening for fluidically connecting the piston compartment to ambient atmosphere. A valve controls airflow between the piston compartment and the inner space of the tire. Airflow between the piston compartment and the inner space is allowed when the valve is opened and prevented when the valve is closed. The piston is movable within the piston compartment between an air intake position, in which the intake opening fluidically connects the piston compartment and the ambient atmosphere, and a compression position, in which the piston fluidically seals the piston compartment from the intake opening, thereby creating a compression chamber. The piston opens and closes the valve, and cycles between the air intake and the compression positions, through application of centrifugal force onto the self-inflation device by rotation of the tire.

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 vehicle tire includes a selectively actuated stud deployment system for increased traction. The studs are contained in cells in the surface of the tire and forced to deploy by pneumatic or fluid pressure. When the pressure is released, the studs retract.

Systems and methods for inflating a tire are described herein. The systems and methods use a centrifugal force acting on a piston or the inertia of the piston to compress air to inflate the tire. Compressed air is ported into the tire, maintaining the pressure of the tire.

A self-inflation device for maintaining pressure in a tire, the self-inflation device includes a body having a piston compartment and an intake opening external to an inner space of the tire and a piston housed in the piston compartment and having a piston opening internal to the inner space. The piston is moved to a pulled position by centrifugal force applied by rotation of the tire to open the intake opening, and moved to a pushed position by air pressure from the inner space to block the intake opening and create a compression chamber within the piston compartment. The self-inflation device further includes a valve separating the compression chamber and the piston opening. The valve is opened when the piston is in the pushed position to allow airflow between the compression chamber and the inner space.

A tire air filling device according to one embodiment includes a cylinder having a first opening communicating with a tire; and a weight 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 airtight member interposed between the weight and an inner surface of the cylinder; and a weight spring that biases the weight to a side opposite to the tire. The cylinder has a second opening on a side opposite to the first opening, and a cap that is detachably attached to the second opening is provided.

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.