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US 4,792,938 AGranted
Low-noise bearing for phonograph turntables and the like
OwnerWilliam H. Firebaughinventor
Life of this patent
Estimating the term…
Abstract
A low-noise (low "rumble") segmented bearing for high-fidelity phonograph turntables and the like. In a preferred belt-driven form, the bearing consists of four small, spaced polyurethane pads disposed so that the tension of the belt keeps the shaft in contact with all of them. A fifth pad supports the end of the shaft. The bearing is immersed in lubricant.
Claims4
A phonograph turntable having a central shaft,
- a housing surrounding said shaft, and
- low-noise bearing means fixed in said housing and engaging slidably the cylindrical surface of said shaft and comprising:
- a first and a second pair of small, angularly-spaced, fixed bearing pads,
- said pads being linearly spaced along said shaft to provide bearing engagement therewith at four spaced points, and further comprising:
- two pairs of adjusting screws extending through the wall of said housing,
- one of said pads being fastened to the inner end of each said screw,
- the end of each said pad being shaped as a generally convex figure of revolution.
4 more elements
A phonograph turntable having a central shaft,
- a housing surrounding said shaft and closed at the bottom and having an upper rim portion, and
- low-noise bearing means fixed in said housing and engaging slidably the cylindrical surface and the flat lower end of said shaft and comprising:
- an upper and a lower pair of small, generally convex, angularly-spaced fixed radial bearing pads,
- said pairs being linearly spaced along said shaft and facing generally oppositely, and supporting said cylindrical surface at four spaced points, and
- a small generally convex fixed thrust pad disposed to engage and support said lower end generally in point contact,
- all said pads being of a plastic-like material which is soft compared to said shaft,
- said upper pair being disposed substantially below said upper rim of said housing.
4 more elements
Dependencies are inferred from the claim text.