Portable computer hard disk protective reflex system

Abstract

A protective reflex system for a portable computer hard disk initiates protective action before the hard disk suffers the shock of an impact in the event they fall from, for example, a user's lap. A three axis accelerometer is mounted in the portable computer. The output of the accelerometer is continuously monitored by a dedicated processor. In the event of an acceleration event within a preset range of values, the dedicated processor passes a high priority interrupt to the central processing unit of the portable computer and then proceeds to park the disk heads. Alternately, the interrupt routine of the central processing unit may also cause the park operation. In addition to park operation, a brake operation may be performed by either the dedicated processor or the central processing unit.

I claim: 
     
       1. A protective reflex system for a portable computer hard disk which initiates protective action before the hard disk suffers .[.the.]. .Iadd.a .Iaddend.shock of an impact, said hard disk .[.having.]. .Iadd.including .Iaddend.at least .[.a.]. one head flying above at least one .[.motor driven.]. .Iadd.motor-drive .Iaddend.rotating disk and said portable computer .[.having.]. .Iadd.including .Iaddend.a central processing unit, said protective reflex system comprising: a three axis accelerometer mounted in the portable computer and generating signals proportional to accelerations along three axes; and   a dedicated processor for continuously monitoring said accelerometer signals and computing an acceleration vector, said dedicated processor further comparing a .[.scaler.]. .Iadd.scalar .Iaddend.value of said acceleration vector to a preset range of values .[.close to 1G.]. corresponding to a free fall condition and passing a high priority interrupt to the central processing unit of the portable computer when said .[.scaler.]. .Iadd.scalar .Iaddend.value falls within said preset range;   one of said dedicated processor .[.or.]. .Iadd.and .Iaddend.said central processing unit calling a routine to park said at least one head of the hard disk .[.rapidly.]. before the hard disk suffers .[.the.]. .Iadd.a .Iaddend.shock of an impact.   
     
     
       2. The protective reflex system recited in claim 1 wherein one of said dedicated processor .[.or.]. .Iadd.and .Iaddend.said central processing unit further calls a routine to brake .[.the.]. .Iadd.a .Iaddend.rotation of said hard disk. 
     
     
       3. The protective reflex system recited in claim 2 wherein said dedicated processor calls the routine to park said at least one head of the hard disk .[.rapidly.]. while said central processing unit calls the routine to brake the rotation of said hard disk, said routines .Iadd.to park and to brake .Iaddend.being processed simultaneously in parallel by said dedicated processor and said central processing unit. 
     
     
       4. The protective reflex system recited in claim 1 wherein said hard disk further .[.has.]. .Iadd.includes .Iaddend.a frame and said accelerometer is mounted on said frame. 
     
     
       5. The protective reflex system recited in claim 1 wherein said dedicated processor calls the routine to park said at least one head of the hard disk .[.rapidly.].. 
     
     
       6. A .[.reflexive.]. method for protecting a portable computer hard disk by initiating protective action before the hard disk suffers .[.the.]. .Iadd.a .Iaddend.shock of an impact, said hard disk .[.having.]. .Iadd.including .Iaddend.at least .[.a.]. one head flying above at least one .[.motor driven.]. .Iadd.motor-driven .Iaddend.rotating disk.Iadd., a three-axis accelerometer and a dedicated processor .Iaddend.and said portable computer .[.having.]. .Iadd.including .Iaddend.a central processing unit .[.and being further provided with a three-axis accelerometer and a dedicated processor.]., said reflexive method comprising the steps of: monitoring.Iadd., .Iaddend.by said dedicated processor.Iadd., .Iaddend.signals from said accelerometer proportional to accelerations along three axes;   computing.Iadd., .Iaddend.by said dedicated processor.Iadd., .Iaddend. an acceleration vector and comparing a .[.scaler.]. .Iadd.scalar .Iaddend.value of said acceleration vector to a preset range of values .[.close to 1G.]. corresponding to a free fall condition and passing a high priority interrupt to the central processing unit of the portable computer when said .[.scaler.]. .Iadd.scalar .Iaddend.value .[.exceeds.]. .Iadd.falls within .Iaddend.said preset range; and   parking.Iadd., .Iaddend.by said dedicated processor or said central processing unit.Iadd., .Iaddend.said at least one head of the hard disk .[.rapidly.]. before the hard disk suffers .[.the.]. .Iadd.a .Iaddend.shock of an impact.   
     
     
       7. The .[.reflexive.]. method recited in claim 6 further comprising the step of braking by one of said dedicated processor .[.or.]. .Iadd.and .Iaddend.said central processing unit .[.the.]. .Iadd.a .Iaddend.rotation of said hard disk. 
     
     
       8. The .[.reflexive.]. method recited in claim 7 wherein said step of parking said at least one head of the hard disk .[.rapidly.]. is performed by said dedicated processor while said step of braking the rotation of said hard disk is performed by said central processing unit, said steps .Iadd.of parking and braking .Iaddend.being performed simultaneously in parallel by said dedicated processor and said central processing unit.Iadd., respectively.Iaddend.. 
     
     
       9. The .[.reflexive.]. method recited in claim 6 wherein said step of parking said at least one head of the hard disk .[.rapidly.]. is performed by said dedicated processor. .Iadd.10. A storage device comprising: a moving storage medium;   at least one head positioned in transducing relationship with respect to said moving storage medium; and   a system for protecting the storage device, said system comprising: an accelerometer, operatively coupled to the storage device, for generating a signal proportional to an acceleration of the storage device;   means for comparing a magnitude of said signal to a predetermined magnitude, said predetermined magnitude being associated with a shock of an impact; and   means for repositioning said at least one head responsive to said magnitude of said signal generated by said accelerometer being greater than said predetermined magnitude and prior to said storage device suffering a shock of an impact. .Iaddend. .Iadd.11. The storage device of claim 10, wherein said means for repositioning places said at least one head in a protective position. .Iaddend. .Iadd.12. The storage device of claim 10, wherein said means for repositioning parks said at least one head over a portion of said moving storage medium not containing data previously written to said     
     
     
        moving storage medium. .Iaddend. .Iadd.13.  The storage device of claim 10, wherein said means for repositioning parks said at least one head in a nontransducing position. .Iaddend. .Iadd.14. A storage device comprising: a moving storage medium;   at least one head positioned in transducing relationship with respect to said moving storage medium; and   a system for protecting the storage device, said system comprising: a three-axis sensing device coupled to the storage device, for generating a signal proportional to an acceleration of the storage device;   means for comparing a magnitude of said signal to a predetermined magnitude, said predetermined magnitude being associated with a shock of an impact; and   means for moving said at least one head positioned in transducing relationship with respect to said moving storage medium responsive to said magnitude of said signal being greater than said predetermined magnitude and prior to said storage device suffering a shock of an impact. .Iaddend. .Iadd.15. The storage device of claim 14, wherein said means for moving positions said at least one head to a nontransducing position. .Iaddend. .Iadd.16. The storage device of claim 14 wherein said means for moving parks said at least one head over a portion of said moving storage medium not containing data previously written to said moving storage medium. .Iaddend. .Iadd.17. A storage device comprising:     a moving storage medium;   at least one head movably positioned in transducing relationship with respect to said moving storage medium; and   a system for protecting the storage device, said system comprising: a three-axis sensing device coupled to the storage device, for generating a signal proportional to an acceleration of the storage device;   means for comparing a magnitude of said signal to a predetermined magnitude, said predetermined magnitude being associated with a shock of an impact; and   means for stopping movement of at least one of said moving storage medium and said at least one head, responsive to said magnitude of said signal being greater than said predetermined magnitude and prior to said storage     
     
     
        device suffering a shock of an impact. .Iaddend. .Iadd.18.  A method of protecting data stored on a hard disk drive, said hard disk drive including at least one disk having a portion of the disk storing data, at least one transducing head positioned in transducing relation with respect to said at least one disk, an accelerometer and a microprocessor, said method comprising the steps of: comparing a signal from said accelerometer to a predetermined range of levels, said predetermined range of levels being associated with a shock of an impact; and   moving said at least one transducing head in response to said signal from said accelerometer being within said predetermined range of levels and prior to said hard disk drive suffering a shock of an impact. .Iaddend. .Iadd.19. The method of protecting data of claim 18, wherein the step of moving said at least one transducing head includes a step of parking said at least one transducing head off said at least one disk. .Iaddend. .Iadd.20. The method of protecting data of claim 18, wherein the step of moving said at least one transducing head includes a step of parking said at least one transducing head off the portion of said disk storing data.   
     
     
        .Iaddend. .Iadd.21.  A storage device comprising: a moving storage medium;   at least one head movably positioned in transducing relationship with respect to said moving storage medium; and   a system for protecting the storage device, said system comprising: a three-axis accelerometer, operatively coupled to the storage, device, for generating a signal proportional to an acceleration of the storage device;   means for comparing a magnitude of said signal to a predetermined magnitude, said predetermined magnitude being associated with a shock of an impact; and   means for interrupting an operation of the storage device responsive to said magnitude of said signal being greater than said predetermined magnitude and prior to said storage device suffering a shock of an impact. .Iaddend. .Iadd.22. The storage device of claim 21, wherein said means for interrupting includes means for interrupting an operation of said at least one head. .Iaddend. .Iadd.23. The storage device of claim 22, wherein said means for interrupting includes means for interrupting a write operation of said at least one head. .Iaddend. .Iadd.24. The storage device of claim 21, wherein said means for interrupting includes means for stopping a movement of at least one of said moving storage medium and said at least one head. .Iaddend.