Disk drive apparatus and method including power backup

• US 5,602,805 A
• Filed: 01/13/1995
• Issued: 02/11/1997
• Est. Priority Date: 01/20/1994
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited
• Original Assignee: Ricoh Company Limited
• Inventors: Chigita, Kazuhiro
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): MAI, SON LUU
• Application Number:
  US08/372,666
• Time in Patent Office: 760 Days
• Field of Search: 369/53, 369/13, 369/243, 369/235, 360/69, 365/228, 365/229
• US Class Current: 369/13.02
• CPC Class Codes: G11B 11/10595 Control of operating function
• CPC Class Codes: G11B 19/04 Arrangements for preventing, inhibiting, or warning against double recording on the same blank or against other recording or reproducing malfunctions
• CPC Class Codes: G11B 33/121 the apparatus comprising a single recording/reproducing device
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 9/061 for DC powered loads

Abstract

The magneto-optical disk drive apparatus according to the present invention sends a notice for inhibition of writing write data into a magneto-optical disk to a host computer when a volume of electric charge in a secondary battery has not reached a predetermined level, so that, even when power supply from outside is disconnected, write data already stored in a write buffer can safely and accurately be written into a magneto-optical disk.

Claims

1. A magneto-optical disk drive apparatus having a function for reading or writing data into a magneto-optical disk comprising:

a magneto-optical disk drive;

a secondary battery consisting of a plurality of cells each storing power to be supplied to said magneto-optical disk drive from outside;

an electric charge volume detector for detecting a volume of electric charge stored in said secondary battery;

a write buffer for storing therein write data from a host computer;

a current switch for switching a current to said magneto-optical disk drive to that from said secondary battery when power supply is stopped;

a spindle motor for driving said magneto-optical disk; and

a controller for controlling said magneto-optical disk drive,

wherein said writing write data into said magneto-optical disk is inhibited when a volume of electric charge stored in said secondary battery has not reached a predetermined level.

2. A magneto-optical disk drive apparatus according to claim 1, further comprising a write data volume controller for limiting a volume of write data to be stored in said write buffer according to a volume of electric charge stored in said secondary battery.

3. A magneto-optical disk drive apparatus according to claim 1, further comprising a rotational speed controller for stopping power supply to said spindle motor once when external power supply is stopped, and power supply to said magneto-optical disk drive is switched to a secondary battery and maintaining the rotational speed of said spindle motor at a predetermined level when the rotational speed of said spindle motor has dropped to the predetermined level, wherein said write data stored in said write buffer writes into a magneto-optical disk when the rotational speed of said spindle motor is kept at the predetermined level.

4. A magneto-optical disk drive apparatus according to claim 3 further comprising:

a first clock switch for switching an operating clock of said controller for a magneto-optical disk drive from a normal clock to a slower clock when power supply to said spindle motor is once stopped; and

a second clock switch for switching an operating clock of said controller to the normal clock when the rotational speed of said spindle motor has dropped to a predetermined level and the rotational speed of said spindle motor is kept at the predetermined level.

5. A magneto-optical disk drive apparatus according to claim 1 further comprising a selector for selecting a cell in which a volume of electric charge has reached a predetermined level with said electric charge volume detector for detecting a volume of electric charge in each cell constituting said secondary battery consisting of a plurality of cells and supplying power to said magneto-optical disk drive.

6. A magneto-optical disk drive apparatus according to claim 1, further comprising a rotational speed controller for stopping power supply to said spindle motor once when external power supply is stopped, and power supply to said magneto-optical disk drive is switched to said secondary battery and maintaining a rotational speed of said spindle motor at a predetermined level when the rotational speed of said spindle motor has dropped according to a volume of electric charge stored in said secondary battery to said predetermined level, wherein said write data stored in said write buffer is written into said magneto-optical disk when the rotational speed of said spindle motor is kept at said predetermined level.

7. A magneto-optical disk driving method comprising the steps of:

making a determination as to whether an external power is being supplied;

charging a secondary battery when the external power is being supplied;

detecting a volume of electric charge stored in said secondary battery;

switching power supply from said secondary battery when the external power is not being supplied;

making a determination as to whether a write command has been received;

making a determination as to whether a volume of electric charge stored in said secondary battery is more than a specified value;

writing a write data in a write buffer into said magneto-optical disk when said volume is more than said specified value; and

outputting a notice to a host computer inhibiting data write when said detected volume of electric charge is not more than said specified value.

8. A magneto-optical disk driving method comprising the steps of:

receiving a write command;

detecting a volume of electric charge stored in a secondary battery;

computing a volume of data which can be written according to said detected volume of electric charge;

receiving said computed volume of data and writing it in said magneto-optical disk;

making a determination as to whether data write can be executed further with a remaining volume of electric charge stored in said secondary battery; and

outputting a notice to a host computer inhibiting data write when it is determined that further data write can not be executed with the remaining volume of electric charge stored in said secondary battery.

9. A magneto-optical disk driving method comprising the steps of:

receiving a write command;

stopping power supply from a secondary battery to a spindle motor;

making a determination as to whether a rotational speed of said spindle motor has dropped to a specified range;

resuming power supply to said spindle motor and maintaining said rotational speed; and

writing data in a write buffer into said magneto-optical disk.

10. A magneto-optical disk driving method comprising the steps of:

receiving a write command;

stopping power supply from a secondary battery to a spindle motor;

switching a clock to a clock slower than that in the normal operating mode;

making a determination as to whether a rotational speed of said spindle motor has dropped to a specified range;

restoring a clock in said normal operating mode;

resuming power supply to said spindle motor and maintaining said rotational speed; and

writing data in a write buffer into said magneto-optical disk.

11. A magneto-optical disk driving method comprising the steps of:

charging each of a plurality of secondary batteries;

detecting a volume of electric charge in each secondary battery;

making a determination as to whether a volume of electric charge in each secondary battery is higher than a predetermined specified value;

keeping a cell selector in a connected state when said volume is more than said predetermined specified value; and

separating a cell selector when said volume is less than said predetermined specified value.

12. A magneto-optical disk driving method comprising the steps of:

making a determination as to whether an external power is being supplied;

charging a secondary battery when the external power is being supplied;

detecting a volume of electric charge stored in the secondary battery;

switching power supply to that from said secondary battery when the external power is not being supplied;

stopping power supply from said secondary battery to a spindle motor;

computing a rotational speed of said spindle motor enabling its operation from a volume of electric charge in said secondary battery;

making a determination as to whether the rotational speed of said spindle motor has dropped to a specified range;

resuming power supply to said spindle motor and maintaining said rotational speed; and

writing data in a write buffer into said magneto-optical disk.