Patent · US Expired

Disc clamp employing resilient cone for spreading balls

US4958839A · kind A · utility

51Cited by
4References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 12, 1988
Grant dateSep 25, 1990
Priority date
Expiry dateJul 12, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T279/1091
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A ball-type clamping mechanism for clamping computer hard disks in a disk tester for accurate measuring of the disk's parameters comprises a cup-shaped support (10) which is installed on a rotating part of the tester and serves to support a computer hard disk (20) which rests on the upper surface of the support. The support has a cylindrical opening (12) with a diameter equal to or slightly greater than the diameter of the disk opening. Slidingly inserted into the support (10) is a cylindrical retainer (26) which carries clamping balls (28) uniformly spaced from each other in a circumferential direction and located in recesses (30) formed in the side wall of the retainer. The balls have a diameter larger than the side wall of the retainer (26). A pull rod (40) passes through the central opening in the bottom wall of the support and carries a clamping cone (42) which is made from a resilient material softer than the material of the balls (28). When the rod is pulled down, a conical surface (50) of the clamping cone (42) pushes the balls radially outwardly into contact with the inner periphery of the hard disk, so that the disk is clamped. The number of balls exceeds three, so that a…

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