公开(公告)号：GB1276969A

公开(公告)日：1972-06-07

申请号：GB5825970

申请日：1970-12-08

Applicant: IBM

Inventor： DAVY JOHN COLIN ,  HEATH JOHN STEWART

IPC: G11B5/48 ,  G11B5/55

Abstract: 1276969 Head supports for magnetic disc records INTERNATIONAL BUSINESS MACHINES CORP 8 Dec 1970 58259/70 Heading G5R Heads 19, Fig. 2, or 31, Fig. 4, are mounted on a radially-extending strut 21 or 41, which lies close enough to the record disc 13 to share in any rise in temperature of the disc and is supported on an axis 23 passing through the axis of rotation of the disc. The heating of the strut may be speeded by an electrical heater 27 mounted thereon. The position of the heads 31, Fig. 4, may be adjusted by means of a lead screw 33.

公开(公告)号：DE3069643D1

公开(公告)日：1984-12-20

申请号：DE3069643

申请日：1980-11-28

Applicant: IBM

Inventor： DAVY JOHN COLIN ,  FENTON BRIAN PETER ,  RAMAGE JOHN GILBERT

IPC: H02P1/30 ,  H02P1/42

Abstract: A single phase induction motor control system employs power line assisted starting and runs at higher than power line frequency from an electronically generated inverter supply. This inverter supply is employed to provide an out of phase mains frequency signal to the run winding during starting in order to create the rotating magnetic field needed to start the motor. After the motor has started, the power line supply is disconnected from the start winding and the inverter supply frequency is increased gradually to a final value corresponding to the desired operating speed. In this system no phase shifting capacitors are needed to provide the out of phase starting voltage and the run winding is optimized for running conditions.