Magnetic holddown for magnetic disc system
Abstract
Abstract A MAGNETIC BOLDDWON SYSTEM FOR PROVIDING AT SELECTED TIMES A MAGNETIC HOLDDOWN OF A MAGNETIC DISC WHEREIN THE DISC INCLUDES A RING OF MAGNETIC MATERIAL AND WHEREIN THE DISC IS TO BE HELD ON A SPINDLE ASSEMBLY IN A MAGNETIC DISC RECORDING AND REPRODUCING SYSTEM. THE SPINDLE ASSEMBLY INCLUDES A CENTRAL SPINDLE, A RIM MEMBER AND AN INTERCONNECTING WEB ORTION AND WITH THE WEB PROTION INCLUDING MAGNETIC SECTIONS SPACED APART BY A NONMAGNETIC SECTION. A STATIONARY ELECTROMAGNET IS LOCATED BELOW THE SPINDLE ASSEMBLY AND PROVIDES WHEN ENERGIZED A MAGNETIC FIELD TO PASS THROUGH THE MAGNETIC SECTIONS OF THE WEB PORTION TO INTERACT WITH THE RING OF MAGNETIC MATERIAL WHICH IS PART OF THE MAGNETIC DISC TO HOLD THE MAGNETIC DISC AGAINST THE SPINDLE ASSEMBLY. THE STATIONARY ELECTROMAGNET IS ALWAYS ENERGIZED WHEN THE MOTOR DRIVING THE SPINDLE ASSEMBLY IS ENERGIZED. THE STATIONARY ELECTROMAGNET IS ENERGIZED FOR A PREDETERMINED PERIOD OF TIME AFTER THE MOTOR DRIVING THE SPINDLE ASSEMBLY IS DE-ENERGIZED AND THE STATIONARY ELECTROMAGNET IS ENERGIZED FOR A PREDETERMINED PERIOD OF TIME WHEN POWER IS APPLIED TO THE SYSTEM BUT BEFORE THE MOTOR DRIVING THE SPINDLE ASSEMBLY IS ENERGIZED.
Inventors
- 👤 Albert V Mowrey
- 👤 John H Huiskes
- 👤 Abraham Brand
Bibliographic Details
Claims Analysis
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