US3972535A — Spindle drive motor

Claim 1

Independent Claim 98 words

In a flexible disk drive system of the type including a rotatable hub and means for clamping a portion of a disk against said hub to rotate said disk as said hub is rotated, the improvement comprising: stepper motor means including a stator and a rotor mounted for rotation with respect thereto, said stator including pairs of opposed radially directed poles each having a coil wound thereon, said rotor comprising a cylinder of ferromagnetic material having a plurality of teeth fixed along the circumference thereof and a drive shaft fixed thereto coincident with the axis of said cylinder;

Claim 2

Dependent Claim 98 words

In a flexible disk drive system of the type including a rotatable hub and means for clamping a portion of a disk against said hub to rotate said disk as said hub is rotated, the improvement comprising: stepper motor means including a stator and a rotor mounted for rotation with respect thereto, said stator including pairs of opposed radially directed poles each having a coil wound thereon, said rotor comprising a cylinder of ferromagnetic material having a plurality of teeth fixed along the circumference thereof and a drive shaft fixed thereto coincident with the axis of said cylinder;

Claim 3

Dependent Claim 104 words

means directly connecting said hub to said drive shaft for rotation therewith; and motor control means coupled to said stepper motor means for successively applying energizing pulses to the coil of successive pole pairs and including means for initially energizing coils of a selected pole pair for a selected detent period, and for subsequently successively applying energizing pulses to the coils wound on said pole pairs following said selected pole pair, said energizing pulses decreasing in duration from an initial to a final duration during a selected speed increase interval, whereby during said interval the motor speed increases from zero to a desired speed.

Claim 4

Dependent Claim 104 words

means directly connecting said hub to said drive shaft for rotation therewith; and motor control means coupled to said stepper motor means for successively applying energizing pulses to the coil of successive pole pairs and including means for initially energizing coils of a selected pole pair for a selected detent period, and for subsequently successively applying energizing pulses to the coils wound on said pole pairs following said selected pole pair, said energizing pulses decreasing in duration from an initial to a final duration during a selected speed increase interval, whereby during said interval the motor speed increases from zero to a desired speed.

Claim 5

Dependent Claim 58 words

The system of claim 1 including command source means for supplying a first control signal when it is desired to drive said disk and control means for supplying a second control signal when said disk is properly clamped against said hub; and gate means responsive to said first and second control signals for actuataing said motor control means.

Claim 6

Independent Claim 137 words

A system for driving a flexible magnetic disk of the type which has a central opening and is contained within a cartridge said comprising: a motor including a stator and a rotor mounted concentrically about a common axis; said rotor comprising a cylinder of ferromagnetic material having uniformly spaced teeth formed along the periphery thereof and a drive shaft fixed thereto extending along said common axis; bearing means supporting said rotor for rotational movement about said common axis; a hub mounted directly on the end of said drive shaft remote from said rotor; clamping means for selectively clamping the portion of a disk around the central opening thereof against said hub; and motor control means for supplying pulses to said motor of increasing frequency and decreasing duration to accelerate said rotor from rest to a desired speed.

Claim 7

Independent Claim 137 words

A system for driving a flexible magnetic disk of the type which has a central opening and is contained within a cartridge said comprising: a motor including a stator and a rotor mounted concentrically about a common axis; said rotor comprising a cylinder of ferromagnetic material having uniformly spaced teeth formed along the periphery thereof and a drive shaft fixed thereto extending along said common axis; bearing means supporting said rotor for rotational movement about said common axis; a hub mounted directly on the end of said drive shaft remote from said rotor; clamping means for selectively clamping the portion of a disk around the central opening thereof against said hub; and motor control means for supplying pulses to said motor of increasing frequency and decreasing duration to accelerate said rotor from rest to a desired speed.

Claim 8

Dependent Claim 66 words

The system of claim 3 wherein said stator includes a plurality of poles arranged in pairs, each pole pair being comprised of first and second aligned poles extending oppositely toward said common axis; a plurality of separate coils, each wound on one of said poles; said motor control means including means for energizing said pole pairs in sequence by successively applying pulses to the coils thereof.

Claim 9

Dependent Claim 41 words

The system of claim 4 including means responsive to said clamping means clamping a disk against said hub for supplying an enabling signal; and wherein said motor control means includes means responsive to said enabling signal for generating a drive signal.

Claim 10

Dependent Claim 118 words

The system of claim 5 wherein said motor control means includes one shot means settable by the start of said drive command signal to a selected first state for a selected duration with said one shot means being switchable to a second state at the end of said selected duration; detent drive means coupled to said one shot means for initially applying energizing pulses to coils wound about a selected pole pair when said one shot is in said first state; and circuit means for subsequently successively applying energizing pulses to the coils wound about different pole pairs, said pulses decreasing in duration from a first predetermined duration to a second predetermined duration during a selected time period.

Claim 11

Dependent Claim 61 words

The system of claim 4 wherein each of said poles defines a pair of teeth spaced a distance equal to the distance between adjacent teeth along said rotor periphery; and wherein poles of different pole pairs are spaced along said rotor periphery such that the teeth of only one pole pair at a time are aligned with teeth on said rotor.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1979-08-03	1980-02-02	1980-08-03	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1983-08-03	1984-02-02	1984-08-03	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1987-08-03	1988-02-02	1988-08-03	$7700.00	Window Closed / Lapsed

Spindle drive motor

Abstract

Inventors

Bibliographic Details

Claims Analysis

References Cited (Backward Citations)

USPTO Annuity & Maintenance Windows

Assigned Categories & Tags

Assign Category Tag