Abstract: A tire pressure indicating apparatus has a plurality of interconnected concentric cylindrical parts including, a base, a flexible diaphragm providing an annular U-shaped wall, a valve body, an indicator sleeve, a cover and a spring, the spring compressively engaged between the cover and the indicator sleeve, such that a pressure differential across the diaphragm acts in opposition to the spring to move the indicator sleeve axially so as to display a colored surface of the sleeve through a window in the cover, or an alternate color uncovered by sleeve movement.

Abstract: A tire pressure indicating apparatus has a plurality of interconnected concentric cylindrical parts including, a base, a flexible diaphragm providing an annular U-shaped wall, a valve body, an indicator sleeve, a cover and a spring, the spring compressively engaged between the cover and the indicator sleeve, such that a pressure differential across the diaphragm acts in opposition to the spring to move the indicator sleeve axially so as to display a colored surface of the sleeve through a window in the cover, or an alternate color uncovered by sleeve movement.

Abstract: An inner cylinder has a reduced diameter portion and a proximally disposed transverse aperture. An outer cylinder has a distally disposed transverse hole. The inner and outer cylinders are coaxially disposed and sealingly engaged distally, thereby forming a cylindrical space between them. A cylindrical piston within the cylindrical space is slidably urged proximally by a coil spring. A cylindrical seal separates the space between a higher pressure proximal zone and a lower pressure distal zone, the seal moving with the piston. A mounting cylinder is sealingly engaged with the outer cylinder and terminates proximally with an internal thread for engaging a typical valve stem or a wheel mount for mounting the apparatus on an automotive wheel in place of a typical valve stem.

Abstract: A tire pressure indicator is mounted onto the fill stem of a tire and provides a window for indicating if the tire has adequate pressure or not. The indicator show adequate, marginal and underinflated conditions by color bands opposite the window. The pressure indicator may be permanently mounted onto the tire and used to fill the tire and maintain pressure in the tire. As the tire is filled the indicator moves from one color band to the next until the indicator shows that adequate pressure has been attained whereupon the hose may be disconnected.