Browse Prior Art Database

Optimization of Load/Unload with temperature sensor Disclosure Number: IPCOM000013740D
Original Publication Date: 2000-Jan-01
Included in the Prior Art Database: 2003-Jun-18
Document File: 2 page(s) / 42K

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Disclose is a method of Load/Unload function optimization by temperature sensor.

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Optimization of Load/Unload with temperature sensor

   Disclose is a method of Load/Unload function optimization by temperature

This invention has aimed at the following.
1. The performance of the VCM driver is used for FULL by detecting the
temperature with a temperature sensor, and changing

   GAIN of the device, which detects a reversed current. (LOAD/UNLOAD time
become·short, and stabilization of behavior)

   2. An unstable operation is pressed by changing the size of the current of
begin the kick of Load in proportion by detected
temperature. (It is possible to control at a proper not self-assertive early,
come late self-assertive, speed)

   Therefore, The behavior of LOAD can be done accurate control without the
influence of a surrounding temperature.

The relation between VCM current value and reversed current is measured before
of Load/Unload function.

So, The inclination of the correlation and offset are actually measured.
This inclination value optimized becomes small.

However, the resistance of VCM changes by the ambient temperature's changing
and doing, and the value of the correlation changes, too. (Show Fig.1)


The detected value of reverse current become strange when the current thrown
into VCM is output to the vicinity of the maximum value.

So, Actuator oscillates. The range of the VCM current that can be used in
present HDD to prevent it is narrowed. Therefore, Load/unload
performance becomes bad. GAIN of the reverse current detect is corrected
according to th...