Browse Prior Art Database

Normalized Module Tolerance Process for Multi Process

IP.com Disclosure Number: IPCOM000123914D
Original Publication Date: 1999-Jul-01
Included in the Prior Art Database: 2005-Apr-05
Document File: 1 page(s) / 33K

Publishing Venue

IBM

Related People

Nakagawa, Y: AUTHOR [+4]

Abstract

Disclosed is a process method to minimize total tolerance when each parts has not enough tolerance like microdrive hard disk drive.

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This is the abbreviated version, containing approximately 100% of the total text.

Normalized Module Tolerance Process for Multi Process

   Disclosed is a process method to minimize total tolerance
when each parts has not enough tolerance like microdrive hard disk
drive.

   Microdrive hard disk use COMBO Module to control Mechanical
parts of HDD (Actuator arm, Spindle Motor, and so on).  COMBO Module
has big tolerance in Offset value itself.  Also many Mechanical Marts
have big tolerance distribution.  Normally, it is hard to meet the
controllable range with both COMBO offset and Mechanical parts
tolerance.  Then, it must to be need to tighten the spec for both
tolerances, or to fail at HDD Manufacturing test.

   Following is a Normalized Module Tolerance Process.
  (1) Measure COMBO Module offset value using Normalized
      resistor instead of actual Mechanical parts and store
      COMBO offset value in EEPROM on each card at card
      Manufacturing site.
  (2) Micro code can handle COMBO Module offset using by COMBO
      Offset from EEPROM after assembling with card and Disk
      Enclosure at HDD manufacturing site.

   This method can cancel COMBO Module tolerance, then need
discuss only Mechanical parts tolerance distribution.  No need to
tighten the spec for both.

   This method can be achieved Yield and Quality improvement
without SPEC change.  Also it is possible to avoid Module cost go up.

   This method can be possible to apply any other process
for multi process.