A jewel bearing is a plain bearing in which a metal spindle turns in a jewel-lined pivot hole. The hole is typically shaped like a torus and is slightly larger than the shaft diameter. The jewel material is usually some form of synthetic sapphire, such as ruby. Jewel bearings are used in precision instruments, but their largest use is in mechanical watches.
Read more about Jewel Bearing: History, Characteristics, Uses
Famous quotes containing the words jewel and/or bearing:
“The general who advances without coveting fame and retreats without fearing disgrace, whose only thought is to protect his country and do good service for his sovereign, is the jewel of the kingdom.”
—Sun Tzu (6th–5th century B.C.)
“In our most trivial walks, we are constantly, though unconsciously, steering like pilots by certain well-known beacons and headlands, and if we go beyond our usual course we still carry in our minds the bearing of some neighboring cape; and not till we are completely lost, or turned round,—for a man needs only to be turned round once with his eyes shut in this world to be lost,—do we appreciate the vastness and strangeness of nature.”
—Henry David Thoreau (1817–1862)