# US 5,708,539 A · Disk storage drive > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,708,539 A - Document ID: US5708539A - Status: Granted - Kind: A - Application number: 08/459,743 - Filed: 1995-06-02 - Granted: 1998-01-13 - Earliest claimed: 1980-03-05 - Assignees: Papst Licensing GmbH & Co. KG - Inventors: Bernhard Schuh - Web page: https://patentgrep.com/patent/US5708539A ## CPC - G11B 33/1473: {of/from bearings} - G11B 17/038: Centering or locking of a plurality of discs in a single cartridge - G11B 19/2009: {Turntables, hubs and motors for disk drives; Mounting of motors in the drive (means for clamping of disk to turntable G11B17/022 and subgroups)} - G11B 23/505: {of disk carriers} - G11B 25/043: {using rotating discs} - H02K 5/10: with arrangements for protection from ingress, e.g. water or fingers - H02K 11/014: {Shields associated with stationary parts, e.g. stator cores} - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) ## Abstract A disk storage has one or more disks provided with center holes. An electric motor extends coaxially through these holes and has an external rotor to the outer circumference of which the disks are secured so that they rotate with the rotor. A seal is provided for at least reducing the escape of contaminants from the motor. ## Claims ### Claim 1 A disk storage device comprising: a contaminant-free environment chamber; at least one storage disk having a center hole and mounted in said contaminant-free environment for cooperation with data access heads included in said storage device; a brushless DC motor extending coaxially through said center hole and having a stator and a rotor surrounding the stator, the rotor and the stator mounted inside the chamber; means connecting said storage disk to said rotor for rotation with said rotor; and a narrow gap located near the periphery of the rotor and formed by a portion of the rotor and a stationary part of said device for retarding the escape of contaminants from said brushless DC motor into said contaminant-free environment chamber. ### Claim 2 (depends on 1) The disk storage device of claim 1 wherein said means for retarding the escape of contaminants includes a surface near an axial extremity of said rotor which is spaced closely adjacent to a wall of said contaminant-free chamber. ### Claim 3 (depends on 1) The disk storage device of claim 1 wherein said narrow gap for retarding the escape of contaminants comprises a labyrinth seal formed by a member affixed to a rotating part of said motor cooperating with a member affixed to a stationary part of said motor. ### Claim 4 (depends on 1) The disk storage device of claim 1 in which said narrow gap for retarding the escape of contaminants comprises a labyrinth seal formed by a member affixed to one end of said rotor cooperating with a member affixed to said stator. ### Claim 5 (depends on 1) The disk storage device of claim 1 further comprising an airflow filter positioned within said contaminant-free environment chamber, said contaminant-free environment chamber being formed to direct an airflow through said filter to entrap any contaminants released from said motor into said contaminant-free environment chamber, said airflow being caused by the rotation of said rotor within said contaminant-free environment chamber during operation of said device. ### Claim 6 A disk storage device, comprising: a plurality of walls forming a chamber enclosing a substantially contaminant-free environment for cooperation with data access heads included in said storage device; at least one storage disk having a center hole and mounted in said contaminant-free environment; a brushless DC motor having a stator and a rotor with a substantially cylindrical air gap therebetween, the rotor and the stator mounted within said contaminant-free environment, said rotor having a storage disk mounting part extending coaxially through said center hole; means connecting said storage disk to said storage disk mounting part of said rotor; and a narrow gap formed by a portion of the rotor and a stationary part of said device for reducing the escape of contaminants from said brushless DC motor into said contaminant-free environment. ### Claim 7 (depends on 6) The disk storage device of claim 6 in which said rotor includes at least one portion made of magnetically conductive material peripherally surrounding said stator and further includes an annular permanent magnet affixed to an inner surface of said magnetically conductive portion, said magnet being spaced from said stator by a substantially cylindrical air gap. ### Claim 8 (depends on 7) The disk storage device of claim 7 wherein said motor further comprises a shaft and bearing system rotatably supporting said rotor. ### Claim 9 (depends on 8) The disk storage device of claim 8 in which said narrow gap for reducing the escape of contaminants comprises a cylindrical member affixed to one end of said rotor cooperating with a cylindrical member affixed to said stator. ### Claim 10 (depends on 9) The disk storage device of claim 9 wherein said narrow gap forms a particle movement path having at least one right-angle turn. ### Claim 11 (depends on 10) The disk storage device of claim 10 wherein said narrow gap forms a particle movement path having plural right-angle turns. ### Claim 12 (depends on 8) The disk storage device of claim 8 wherein said motor further comprises a bearing tube affixed to a wall of said contaminant-free chamber, said bearing tube supporting the bearings of said shaft and bearing system, and wherein the shaft of said shaft and bearing system is affixed to one end of said rotor and rotates within said bearings. ### Claim 13 (depends on 12) The disk storage device of claim 12 in which said narrow gap for reducing the escape of contaminants comprises a labyrinth seal formed by a member affixed to one end of said bearing tube cooperating with a member affixed to the end of said rotor at which said shaft is mounted. ### Claim 14 (depends on 12) The disk storage device of claim 12 wherein said narrow gap for retarding the escape of contaminants comprises a labyrinth seal formed by a member affixed to one end of said bearing tube cooperating with a member affixed to the end of said rotor at which said shaft is mounted. ### Claim 15 (depends on 8) The disk storage device of claim 8 in which said narrow gap for reducing the escape of contaminants comprises a labyrinth seal formed by a member affixed to one end of said rotor cooperating with a member affixed to said stator. ### Claim 16 (depends on 6) The disk storage device of claim 6 in which said narrow gap for reducing the escape of contaminants is formed by a surface near an axial extremity of said rotor which is spaced closely adjacent to a wall of said contaminant-free chamber. ### Claim 17 (depends on 6) The disk storage device of claim 6 in which said narrow gap for reducing the escape of contaminants comprises a labyrinth seal formed by a member affixed to a rotating part of said motor cooperating with a member affixed to a stationary part of said motor. ### Claim 18 (depends on 6) The disk storage device of claim 6 further comprising an airflow filter positioned within said contaminant-free environment chamber, said contaminant-free environment chamber being formed to direct an airflow through said filter to entrap any contaminants released from said motor into said contaminant-free environment chamber, said airflow being caused by the rotation of said rotor within said contaminant-free environment chamber during operation of said device. ### Claim 19 A disk storage device, comprising: a plurality of walls forming a chamber enclosing a substantially contaminant-free environment for cooperation with data access heads included in said storage device; at least one storage disk having a center hole and mounted in said contaminant-free environment; a brushless DC motor having a stator and a rotor with a substantially cylindrical air gap therebetween, the rotor and stator mounted within said contaminant-free environment, said rotor having a storage disk mounting part extending coaxially through said center hole; means connecting said storage disk to said storage disk mounting part of said rotor; and a narrow gap formed between a portion of the rotor and a stationary part of the device which is effective for retarding escape of said contaminants from said brushless DC motor to said contaminant-free environment. ### Claim 20 (depends on 19) The disk storage device of claim 19 wherein the narrow gap for retarding escape of said contaminants from said electric motor to said contaminant-free environment comprises a surface near an axial extremity of said rotor which is spaced closely adjacent to a wall of said contaminant-free chamber. ### Claim 21 (depends on 19) The disk storage device of claim 19 wherein the narrow gap for retarding escape of said contaminants from said electric motor to said contaminant-free environment comprises a member affixed to a rotating part of said motor cooperating with a member affixed to a stationary part of said motor. ### Claim 22 (depends on 21) The disk storage device of claim 21 wherein the narrow gap for retarding escape of said contaminants from said electric motor to said contaminant-free environment comprises a cylindrical member affixed to one end of said rotor cooperating with a cylindrical member affixed to said stator. ### Claim 23 (depends on 22) The disk storage device of claim 22 wherein said narrow gap forms a particle movement path having at least one right-angle turn. ### Claim 24 (depends on 23) The disk storage device of claim 23 wherein said narrow gap forms a particle movement path having plural right-angle turns. ### Claim 25 (depends on 19) The disk storage device of claim 19 wherein the narrow gap for retarding escape of said contaminants from said electric motor to said contaminant-free environment comprises a member affixed to one end of said rotor cooperating with a member affixed to said stator. ### Claim 26 (depends on 19) The disk storage device of claim 19 further comprising an airflow filter positioned within said contaminant-free environment chamber, said contaminant-free environment chamber being formed to direct an airflow through said filter to entrap any contaminants released from said motor into said contaminant-free environment chamber, said airflow being caused by the rotation of said rotor within said contaminant-free environment chamber during operation of said device.