Automatic adjustment of magnetic disk protection apparatus and method according to environment

• US 20050073764A1
• Filed: 09/30/2004
• Published: 04/07/2005
• Est. Priority Date: 10/03/2003
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Ogawa, Mitsuru, Shimotono, Susumu, Tanaka, Akiyoshi
• Granted Patent: US 7,154,692 B2
• Time in Patent Office: Days
• US Class Current: 360/60
• 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 20/10 Digital recording or reproducing
• CPC Class Codes: G11B 33/08 Insulation or absorption of undesired vibrations or sounds
• CPC Class Codes: G11B 5/40 Protective measures on heads, e.g. against excessive temperature G11B5/31 takes precedence; protection against wear G11B5/255 ; protective structure of the head: see under structures, e.g. G11B5/3106
• CPC Class Codes: G11B 5/5582 system adaptation for working during or after external perturbation, e.g. in the presence of a mechanical oscillation caused by a shock

Abstract

A portable information processing apparatus in provided with a magnetic disk device switchable to a state providing increased resistance to physical shock upon prediction that such a shock is likely. Under predetermined conditions, a second prediction may be issued that such a shock is no longer likely, allowing the magnetic disk device to switch to a normal state of operations. The shock-resistant state of the magnetic disk device can prevent data access and thus inhibit the progress of important process(es). Upon recognition that an important process is being delayed, the condition for issuing the second prediction may be relaxed to more quickly return the magnetic disk device to a normal operating state.

Claims

1. A portable information processing apparatus comprising:

a magnetic disk device switchable between a first shock-resistant state in which data access to a magnetic disk by a head is enabled and a second shock-resistant state in which data access to the magnetic disk by the head is disabled where said second shock-resistant state provides increased shock resistance as compared to said first shock-resistant state;

at least one first sensor for detecting a first shock-predictive physical quantity, said first shock-predictive physical quantity being a basis for issuing a first prediction that a shock to said magnetic disk device is likely;

at least one second sensor for detecting a second shock-predictive physical quantity, said second shock-predictive physical quantity being a basis for issuing a second prediction that a shock to said magnetic disk device is not likely;

first prediction means for issuing the first prediction in response to an output from said first sensor;

first magnetic disk device switching means for switching said magnetic disk device from the first shock-resistant state to the second shock-resistant state in response to the first prediction;

second prediction means for issuing the second prediction in response to an output from said second sensor after said first magnetic disk device switching means switches said magnetic disk device from the first shock-resistant state to the second shock-resistant state;

second magnetic disk device switching means for switching said magnetic disk device from the second shock-resistant state to the first shock-resistant state in response to the second prediction; and

condition relaxing means for relaxing a condition for issuing the second prediction in response to a delay of a predetermined process in said information processing apparatus caused by the disabled data access due to the second shock-resistant state of said magnetic disk device.

2. The information processing apparatus according to claim 1, further comprising:

at least one event detection means for detecting an event indicating a switch of said information processing apparatus from a first power state to a second power state, said second power state being a lower power state than said first power state; and

power status switching means for switching said information processing apparatus from said first power state to second power state in response to an output from said event detection means;

wherein said predetermined process is a power status switching process performed by said power status switching means.

3. The information processing apparatus according to claim 1, wherein said first shock-resistant state is a state in which the head of said magnetic disk device faces the magnetic disk and said second shock-resistant state is a state in which the head of said magnetic disk device does not face the magnetic disk.

4. The information processing apparatus according to claim 1, wherein:

said second prediction means compares a value relating to the output from said second sensor with a threshold and issues said second prediction on the basis of the result of the comparison; and

said condition relaxing means relaxes said condition by changing said threshold.

5. The information processing apparatus according to claim 4, wherein said first magnetic

disk device switching means comprises status estimation means for estimating a status of said information processing apparatus, said status representing how said information processing apparatus is being used by a user when said first magnetic disk device switching means switches said magnetic disk device from said first shock-resistant state to said second shock-resistant state;

and

said condition relaxing means changes the threshold according to said status estimated by said status estimation means.

6. The information processing apparatus according to claim 1, wherein said second prediction means issues said second prediction on the basis of pattern information relating to a time axis and/or a frequency axis of an output from said second sensor.

7. The information processing apparatus according to claim 6, wherein said pattern information relating to the time axis consists of a series of outputs based on the result of comparisons between an output from said second sensor and a threshold at successive points in time;

and

said condition relaxing means relaxes said condition by changing said threshold.

8. The information processing apparatus according to claim 6, wherein said pattern information relating to the frequency axis consists of a set of outputs based on comparisons between each frequency component of an output from said second sensor and a threshold;

and

said condition relaxing means relaxes said condition by changing said threshold.

9. The information processing apparatus according to claim 1, further comprising prohibition means for prohibiting said condition relaxing means from relaxing the condition during a predetermined time period after said first magnetic disk device switching means switches said magnetic disk device from said first shock-resistant state to said second shock-resistant state.

10. The information processing apparatus according to claim 1, further comprising re-relaxing means for causing said condition relaxing means to further relax the condition for issuing said second prediction if a data read/write disabled state of said magnetic disk device persists for a predetermined time period after said condition relaxing means relaxes the condition.

11. The information processing apparatus according to claim 2, further comprising:

acceleration detection means for detecting acceleration acting on the housing of said information processing apparatus;

statistics collecting means for collecting statistics concerning a history of the acceleration acting on the housing of said information processing apparatus after said event detection means detects an event; and

reflecting means for reflecting the statistics collected by said statistics collecting means in the degree of condition relaxation by said condition relaxing means.

12. A method for controlling a portable information processing apparatus comprising:

issuing a first prediction that a shock is likely to a magnetic disk device of the portable information processing apparatus in response to a first output from a first sensor, where said first sensor issues said first output in response to detecting a first shock predictive physical quantity;

in response to said first prediction, switching said magnetic disk device from a first shock-resistant state in which data access to a magnetic disk by a head is enabled to a second shock-resistant state in which data access to the magnetic disk by the head is disabled, where said second shock-resistant state provides increased shock resistance as compared to said first shock-resistant state;

issuing a second prediction that a shock is not likely to occur to said magnetic disk device after said magnetic disk device is switched from the first shock-resistant state to the second shock-resistant state and in response to a second output from a second sensor, where said second sensor issues said second output in response to detecting a second shock predictive physical quantity;

switching said magnetic disk device from the second shock-resistant state to the first shock-resistant state in response to the second prediction; and

relaxing a condition for issuing the second prediction in response to a delay of a predetermined process in said information processing apparatus caused by the disabled data access due to the second shock-resistant state of said magnetic disk device.

13. The control method according to claim 12, further comprising:

detecting an event indicating a switch of said information processing apparatus from a first power state to a second power state, said second power state being a lower power state than said first power state; and

switching said information processing apparatus from said first power state to said second power state in response to said detection;

wherein said predetermined process in said information processing apparatus is said step of switching said power state of said information processing apparatus.

14. The control method according to claim 12, wherein:

a value relating to the second output is compared with a threshold and a determination is made as to whether or not said second prediction should be issued on the basis of the result of the comparison; and

the condition for issuing said second prediction is relaxed by changing said threshold.

15. The control method according to claim 14, further comprising estimating a status of said information processing apparatus on the basis of said first output, said status representing how said information processing apparatus is being used by a user during a predetermined time period including the point of time at which said magnetic disk device is switched from said first shock-resistant state to said second shock-resistant state;

wherein relaxing said condition for issuing the second prediction comprises changing the threshold on the basis of said estimated status.

16. The control method according to claim 12, wherein said second prediction is issued on the basis of pattern information relating to a time axis and/or a frequency axis of the second output.

17. The control method according to claim 12, wherein the condition for issuing said second prediction is prohibited from being changed during a predetermined time period after said magnetic disk device is switched from said first shock-resistant state to said second shock-resistant state.

18. The control method according to claim 12, wherein the condition for issuing said second prediction is further relaxed in response to a data read/write disabled state of said magnetic disk device persisting after a lapse of a predetermined time period after the condition for issuing said second prediction is relaxed.

19. A computer-readable medium having embodied thereon computer-readable instructions effective when executing on a portable information processing apparatus to:

issue a first prediction that a shock is likely to a magnetic disk device of the portable information processing apparatus in response to a first output from a first sensor, where said first sensor issues said first output in response to detecting a first shock predictive physical quantity;

in response to said first prediction, switch said magnetic disk device from a first shock-resistant state in which data access to a magnetic disk by a head is enabled to a second shock-resistant state in which data access to the magnetic disk by the head is disabled, where said second shock-resistant state provides increased shock resistance as compared to said first shock-resistant state;

issue a second prediction that a shock is not likely to occur to said magnetic disk device after said magnetic disk device is switched from the first shock-resistant state to the second shock-resistant state and in response to a second output from a second sensor, where said second sensor issues said second output in response to detecting a second shock predictive physical quantity;

switch said magnetic disk device from the second shock-resistant state to the first shock-resistant state in response to the second prediction; and

relax a condition for issuing the second prediction in response to a delay of a predetermined process in said information processing apparatus caused by the disabled data access due to the second shock-resistant state of said magnetic disk device.

20. The medium according to claim 19 further comprising computer readable instructions effective when executing on said apparatus to:

detect an event indicating a switch of said information processing apparatus from a first power state to a second power state, said second power state being a lower power state than said first power state; and

switch said information processing apparatus from said first power state to said second power state in response to said detection;

wherein said predetermined process in said information processing apparatus is said step of switching said power state of said information processing apparatus.

21. The medium according to claim 19 wherein said computer-readable instructions are effective when executing on said apparatus to:

compare a value relating to the second output with a threshold and make a determination as to whether said second prediction should be issued on the basis of the result of the comparison; and

relax the condition for issuing said second prediction, when indicated, by changing said threshold.

22. The medium according to claim 19 further comprising computer-readable instructions effective when executing on said apparatus to prohibit the condition for issuing said second prediction from being changed during a predetermined time period after said magnetic disk device is switched from said first shock-resistant state to said second shock-resistant state.

23. The program according to claim 19 further comprising computer-readable instructions effective when executing on said apparatus to further relax the condition for issuing said second prediction in response to a data read/write disabled state of said magnetic disk device persisting after a lapse of a predetermined time period after the condition for issuing said second prediction is relaxed.