公开(公告)号：EP0049946A2

公开(公告)日：1982-04-21

申请号：EP81304124.1

申请日：1981-09-09

Applicant: MINNESOTA MINING AND MANUFACTURING COMPANY

Inventor： Ostroff, Arthur

IPC: G11B17/06 ,  G11B3/08 ,  G11B5/55 ,  G05D3/14

CPC classification number: G11B21/081 ,  G11B3/0952

Abstract: An initialization apparatus for a signal reproducing apparatus having a transducer (18) scanning a plurality of record tracks (16) on a record medium (12) where the position of the transducer (18) is controlled by a stepper motor (22) having fewer steps than the number of record tracks (16) required to be covered. A physical stop (28 or 30) is provided the transducer (18) near a selected "home" record track at one edge of the plurality of record tracks (16). A current selector supplies the phase windings of the stepper motor (22) with a reduced amplitude current during an initialization position. This enables a transducer controller to step the stepper through a sequence of steps under reduced current to the phase windings of the stepper motor (22) until the physical stop (28 or 30) is contacted, thus ensuring knowledge of the initialization of the transducer (18) at the "home" record track.

公开(公告)号：EP0049946B1

公开(公告)日：1984-10-31

申请号：EP81304124.1

申请日：1981-09-09

Applicant: MINNESOTA MINING AND MANUFACTURING COMPANY

Inventor： Ostroff, Arthur

IPC: G11B17/06 ,  G11B3/08 ,  G11B5/55 ,  G05D3/14

CPC classification number: G11B21/081 ,  G11B3/0952

公开(公告)号：EP0049946A3

公开(公告)日：1982-12-08

申请号：EP81304124

申请日：1981-09-09

Applicant: MINNESOTA MINING AND MANUFACTURING COMPANY

Inventor： Ostroff, Arthur

IPC: G11B17/06 ,  G11B03/08 ,  G11B05/55 ,  G05D03/14

CPC classification number: G11B21/081 ,  G11B3/0952

Abstract: An initialization apparatus for a signal reproducing apparatus having a transducer (18) scanning a plurality of record tracks (16) on a record medium (12) where the position of the transducer (18) is controlled by a stepper motor (22) having fewer steps than the number of record tracks (16) required to be covered. A physical stop (28 or 30) is provided the transducer (18) near a selected "home" record track at one edge of the plurality of record tracks (16). A current selector supplies the phase windings of the stepper motor (22) with a reduced amplitude current during an initialization position. This enables a transducer controller to step the stepper through a sequence of steps under reduced current to the phase windings of the stepper motor (22) until the physical stop (28 or 30) is contacted, thus ensuring knowledge of the initialization of the transducer (18) at the "home" record track.