Motor

• US 20060208580A1
• Filed: 05/23/2006
• Published: 09/21/2006
• Est. Priority Date: 07/29/1999
• Status: Active Grant

• Current Assignee: Intellectual Ventures II LLC (Intellectual Ventures LLC)
• Original Assignee: Encap Motor Corporation
• Inventors: Neal, Griffith D.
• Granted Patent: US 7,154,200 B2
• Time in Patent Office: Days
• US Class Current: 310/43
• CPC Class Codes: 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
• CPC Class Codes: H02K 1/04 characterised by the material used for insulating the magnetic circuit or parts thereof
• CPC Class Codes: H02K 1/146 consisting of a generally annular yoke with salient poles
• CPC Class Codes: H02K 1/18 Means for mounting or fastening magnetic stationary parts on to, or to, the stator structures
• CPC Class Codes: H02K 1/182 to stators axially facing the rotor, i.e. with axial or conical air gap
• CPC Class Codes: H02K 1/185 to outer stators
• CPC Class Codes: H02K 1/187 to inner stators
• CPC Class Codes: H02K 11/00 Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection casings, enclosures or supports H02K5/00
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 15/10 Applying solid insulation to windings, stators or rotors
• CPC Class Codes: H02K 15/12 Impregnating, heating or drying of windings, stators, rotors or machines
• CPC Class Codes: H02K 15/14 Casings; Enclosures; Supports
• CPC Class Codes: H02K 15/16 Centering rotors within the stator; Balancing rotors
• CPC Class Codes: H02K 21/16 having annular armature cores with salient poles with homopolar co-operation H02K21/20
• CPC Class Codes: H02K 21/22 with magnets rotating around the armatures, e.g. flywheel magnetos
• CPC Class Codes: H02K 21/24 with magnets axially facing the armatures, e.g. hub-type cycle dynamos
• CPC Class Codes: H02K 2211/03 Machines characterised by circuit boards, e.g. pcb
• CPC Class Codes: H02K 3/38 around winding heads, equalising connectors, or connections thereto
• CPC Class Codes: H02K 3/46 Fastening of windings on the stator or rotor structure
• CPC Class Codes: H02K 3/47 Air-gap windings, i.e. iron-free windings
• CPC Class Codes: H02K 5/02 : Casings or enclosures characterised by the material thereof
• CPC Class Codes: H02K 5/08 : Insulating casings
• CPC Class Codes: H02K 5/1672 : radially supporting the rotary shaft at both ends of the rotor H02K5/1677 takes precedence
• CPC Class Codes: H02K 5/1675 : radially supporting the rotary shaft at only one end of the rotor H02K5/1677 takes precedence
• CPC Class Codes: H02K 5/1677 : radially supporting the rotor around a fixed spindle; radially supporting the rotor directly
• CPC Class Codes: H02K 5/1732 : radially supporting the rotary shaft at both ends of the rotor H02K5/1737 takes precedence
• CPC Class Codes: H02K 5/1735 : radially supporting the rotary shaft at only one end of the rotor H02K5/1737 takes precedence
• CPC Class Codes: H02K 5/225 : Terminal boxes or connection arrangements specially adapted for submersible motors H02K5/132
• CPC Class Codes: H02K 5/24 : specially adapted for suppression or reduction of noise or vibrations
• CPC Class Codes: H02K 7/083 : radially supporting the rotary shaft at both ends of the rotor H02K7/086, H02K7/09 take precedence
• CPC Class Codes: H02K 7/085 : radially supporting the rotary shaft at only one end of the rotor H02K7/086, H02K7/09 take precedence
• CPC Class Codes: H02K 7/086 : radially supporting the rotor around a fixed spindle; radially supporting the rotor directly H02K7/09 takes precedence
• CPC Class Codes: H02K 7/088 : radially supporting the rotor directly
• CPC Class Codes: H02K 7/09 : with magnetic bearings
• CPC Class Codes: H02K 7/14 : Structural association with mechanical loads, e.g. with hand-held machine tools or fans with fan or impeller for cooling the machine H02K9/06
• CPC Class Codes: Y10T 29/49009 : Dynamoelectric machine
• CPC Class Codes: Y10T 29/49012 : Rotor

Abstract

A motor has a stator substantially encapsulated within a body of thermoplastic material; and one or more solid parts used in the motor either within or near the body. The thermoplastic material has a coefficient of linear thermal expansion such that the thermoplastic material contracts and expands at approximately the same rate as the one or more solid parts. In another aspect, a motor for a hard disc drive comprises at least one conductor, at least one magnet, at least one bearing and a shaft; and a monolithic body of thermoplastic material substantially encapsulating the at least one conductor. The bearing is either encapsulated in the thermoplastic material, housed in a hollow cylindrical insert encapsulated in the thermoplastic material, or secured in a bore formed in the body of thermoplastic material. The motor has improved shock resistance.

Claims

1. A motor comprising:

a) a stator substantially encapsulated within a body of thermoplastic material; and

b) one or more solid parts used in the motor either within or near the body;

c) the thermoplastic material having a coefficient of linear thermal expansion such that the thermoplastic material contracts and expands at approximately the same rate as the one or more solid parts.

2. The motor of claim 1 wherein the one or more solid parts comprise a metal.

3. The motor of claim 1 wherein the one or more solid parts comprise a ceramic.

4. The motor of claim 1 wherein the one or more solid parts comprise a metal insert molded within the body.

5. The motor of claim 1 wherein the one or more solid parts comprise a metal bearing.

6. The motor of claim 1 wherein there are a plurality of solid parts that will be either within or near the body, and the solid parts have different coefficients of linear thermal expansion, and the thermoplastic material is designed to have a coefficient of linear thermal expansion intermediate the maximum and minimum coefficients of linear thermal expansion of the different solids.

7. The motor of claim 6 wherein the different solids comprise steel and copper.

8. The motor of claim 6 wherein the different solids comprise metal and ceramic.

9. A motor for a hard disc drive comprising:

a) at least one conductor, at least one magnet, at least one bearing and a shaft; and

b) a monolithic body of thermoplastic material substantially encapsulating the at least one bearing and at least one conductor.

12. The motor of claim 9 meeting hard disc drive manufacturing industry particulate emission standards.

10. A motor for a hard disc drive comprising:

a) at least one conductor, at least one magnet, at least one bearing, a hollow cylindrical insert, and a shaft; and

b) a monolithic body of thermoplastic material substantially encapsulating the insert and the at least one conductor;

c) the bearing being housed in the hollow cylindrical insert.

13. The motor of claim 10 meeting hard disc drive manufacturing industry particulate emission standards.

11. A motor for a hard disc drive comprising:

a) at least one conductor, at least one magnet, at least one bearing and a shaft; and

b) a monolithic body of thermoplastic material substantially encapsulating the at least one conductor;

c) the body of thermoplastic material comprising a bore, and the bearing being secured in the bore.

14. The motor of claim 11 meeting hard disc drive manufacturing industry particulate emission standards.

15. A motor with improved shock resistance comprising:

a) an assembly comprising windings and laminations; and

b) shock absorbing thermoplastic material substantially encapsulating the assembly;

c) wherein the shock absorbing thermoplastic material has a vibration dampening such that the assembly has a reduction of harmonics in the range of 300-2000 Hz of at least 5 decibels compared to an assembly with the same windings and laminations not being encapsulated.

16. A hard disk drive containing the motor of claim 15.