The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 23, 1990
Filed:
Oct. 17, 1988
Sanjoy Ghose, Santa Cruz County, CA (US);
Seagate Technology, Inc., Scotts Valley, CA (US);
Abstract
This invention provides a technique for effectively floating the rotor of a disc drive motor, thereby permitting small motions in the axial (non-critical) direction while maintaining significant stiffness in the radial (critical) direction. This is achieved by providing an electromagnetic actuator including a stepper motor having a housing, a stator located within the housing, and a rotor positionable relative to the stator driving a motor shaft to wind and unwind a band and thereby position the carriage. The drive shaft passes through ball bearings which support the shaft for rotation. The ball bearings themselves fit within an annular end bell portion of the motor housing which defines a channel for the bearing. An injected elastomer forms a tight-fitting ring between the bearings and the internal wall of the end bell, thereby radially supporting the outer race of the bearing. Preload springs are then installed on both sides of the rotor between the internal end walls of the end bells and both outer races of the bearing. The installation of these springs effectively floats the rotor to allow some distortion or movement of the rotor in the axial direction, while minimizing or eliminating the radial deflection components.