Patent · US Expired

Rotating mass balancing system

US5824898A · kind A · utility

13Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 28, 1996
Grant dateOct 20, 1998
Priority date
Expiry dateJun 28, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B19/20
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A system for balancing devices having motors and rotating masses to be coupled to the motors utilizes a momentum transfer mechanism to shift the rotating mass based on sensed imbalance. In this manner the mass is shifted to a position which accounts for the inherent imbalance in both the motor and the mass. A controller receives imbalance information from a velocity sensor and controls a solenoid to strike a base coupled to the motor to shift a lightly clamped mass relative to the motor. In one embodiment, a disk drive has disks initially biased by the system against a hub, and then shifted during rotation to create a disk drive having concentrically aligned disks offsetting imbalance inherent in a motor used to rotate the disks. In one embodiment, the disks are held to the hub by a clamp having screws. The screws are driven simultaneously through the same angle of rotation to ensure that the axial clamping force of each one is substantially equal. In a further embodiment, the screws are formed of a heat shrink material, and shrunk following initial light tightening to provide consistent axial clamping force.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.