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 cleaning machine for cleaning annular discs is disclosed. Annular discs of rigid or flexible material are designed to receive a magnetic coating capable of operating as a memory for a computer. The cleaning machine uses a spindle that aligns and holds the disc. The spindle rotates and high pressure cleaning fluid simultaneously washes both sides of the disc. In one embodiment the spindle has a conical ferrule made of abrasion-resistant rubber. In another embodiment the spindle includes centrifugally-operable hold down arms that extend from the spindle during rotation to keep the disc on the spindle.