JPS56124174A - Magnetic disc device - Google Patents

Magnetic disc device

Info

Publication number
JPS56124174A
JPS56124174A JP2655480A JP2655480A JPS56124174A JP S56124174 A JPS56124174 A JP S56124174A JP 2655480 A JP2655480 A JP 2655480A JP 2655480 A JP2655480 A JP 2655480A JP S56124174 A JPS56124174 A JP S56124174A
Authority
JP
Japan
Prior art keywords
sensor
disc pack
shaft
output
reliability
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP2655480A
Other languages
Japanese (ja)
Inventor
Yasuo Matsumiya
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Ltd
Original Assignee
Hitachi Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP2655480A priority Critical patent/JPS56124174A/en
Publication of JPS56124174A publication Critical patent/JPS56124174A/en
Pending legal-status Critical Current

Links

Landscapes

  • Holding Or Fastening Of Disk On Rotational Shaft (AREA)

Abstract

PURPOSE: To obtain a high-reliability and inexpensive disc pack detecting mechanism, by providing a sensor plate which is moved upward to link with the sensor and detects rotating state of the disc pack due to a notch part when the disc pack is mounted.
CONSTITUTION: When disc pack 5 is not fitted to shaft 7 of spindle 1, shaft 7 is moved downward (to the position indicated by the broken line), and the photo transistor of sensor 14 receives the light of the light emitting diode because sensor plate 12 is not linked to sensor 14, and sensor 14 generates the output. When the disc pack is mounted, sensor plate 12 of shaft 7 is linked to sensor 14, and notch 12a does not exist in the position of sensor 14, and therefore, sensor 14 does not generate the output. When disc pack 5 is rotated and becomes the acceleration state, the period of output pulses of sensor becomes shorter according to rotation of notch part 12a, and thus, it is detected that the disc pack reaches the steady state. As a result, a high-reliability and inexpensive disc pack detecting mechanism is obtained.
COPYRIGHT: (C)1981,JPO&Japio
JP2655480A 1980-03-05 1980-03-05 Magnetic disc device Pending JPS56124174A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2655480A JPS56124174A (en) 1980-03-05 1980-03-05 Magnetic disc device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2655480A JPS56124174A (en) 1980-03-05 1980-03-05 Magnetic disc device

Publications (1)

Publication Number Publication Date
JPS56124174A true JPS56124174A (en) 1981-09-29

Family

ID=12196739

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2655480A Pending JPS56124174A (en) 1980-03-05 1980-03-05 Magnetic disc device

Country Status (1)

Country Link
JP (1) JPS56124174A (en)

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