Dynamoelectric machine having encapsulated coil structure with one or more of phase change additives, insert molded features and insulated pinion

• US 6,946,758 B2
• Filed: 07/10/2003
• Issued: 09/20/2005
• Est. Priority Date: 01/09/2001
• Status: Expired due to Fees

• Current Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Original Assignee: Black & Decker Incorporated (Stanley Black & Decker, Inc.)
• Inventors: Du, Hung T., Walter, Richard T., Verbrugge, Brandon L., Ortt, Earl M., Stone, John C., West, Joshua F., Sell, Michael R.
• Primary Examiner(s): Lam, Thanh
• Application Number:
  US10/616,573
• Publication Number:
  US 20040056537A1
• Time in Patent Office: 803 Days
• Field of Search: 310/43, 310233-235, 310216-217, 310/261
• US Class Current: 310/43
• CPC Class Codes: H01R 39/14 Fastenings of commutators or slip-rings to shafts
• CPC Class Codes: H01R 39/32 Connections of conductor to commutator segment
• CPC Class Codes: H02K 1/30 using intermediate parts, e.g. spiders
• CPC Class Codes: H02K 1/32 with channels or ducts for flow of cooling medium
• CPC Class Codes: H02K 13/006 Structural associations of commutators
• CPC Class Codes: H02K 13/04 Connections between commutator segments and windings
• CPC Class Codes: H02K 15/12 Impregnating, heating or drying of windings, stators, rotors or machines
• CPC Class Codes: H02K 15/165 Balancing the rotor
• CPC Class Codes: H02K 23/00 DC commutator motors or generators having mechanical commutator; Universal AC/DC commutator motors
• CPC Class Codes: H02K 3/12 arranged in slots
• CPC Class Codes: H02K 3/30 Windings characterised by the insulating material
• CPC Class Codes: H02K 3/345 between conductor and core, e.g. slot insulation
• CPC Class Codes: H02K 3/46 Fastening of windings on the stator or rotor structure
• CPC Class Codes: H02K 3/48 in slots
• CPC Class Codes: H02K 3/487 Slot-closing devices
• CPC Class Codes: H02K 3/50 Fastening of winding heads, equalising connectors, or connections thereto
• CPC Class Codes: H02K 3/51 applicable to rotors only
• CPC Class Codes: H02K 5/08 Insulating casings
• CPC Class Codes: H02K 7/04 Balancing means
• CPC Class Codes: H02K 9/06 with fans or impellers driven by the machine shaft
• CPC Class Codes: H02K 9/22 : by solid heat conducting material embedded in, or arranged in contact with, the stator or rotor, e.g. heat bridges
• CPC Class Codes: Y10T 29/49009 : Dynamoelectric machine
• CPC Class Codes: Y10T 29/49011 : Commutator or slip ring assembly
• CPC Class Codes: Y10T 29/49012 : Rotor
• CPC Class Codes: Y10T 29/49071 : by winding or coiling
• CPC Class Codes: Y10T 29/49075 : including permanent magnet or core
• CPC Class Codes: Y10T 29/49078 : Laminated

Abstract

Magnet wires wound in slots in a lamination stack of a dynamoelectric machine are encapsulated, in whole or in part, with thermally conductive plastic. Pre-formed features having a thermal conductivity higher than the thermally conductive plastic are insert molded when the plastic is molded. The pre-formed features may include a finned end cap and a fan. Alternatively, end domes of the plastic over end coils of the wound magnet wires have a metallic layer on them, such as by being metallized. The end domes can be formed with features which are also metallized. The thermally conductive plastic can have a phase change additive in it. The magnet wires can have a layer of heat activated adhesive that is activated when the plastic is molded. Slots in the lamination stack can include slot liners formed of thermally conductive plastic. A fan can be formed when the thermally conductive plastic is molded to encapsulate the magnet wires.

Claims

1. An armature for an electric motor, comprising:

a shaft having a lamination stack thereon;

the lamination stack having a plurality of slots in which magnet wires are wound forming coils having end coils at opposed ends of the lamination stack;

thermally conductive plastic molded around the coils including the end coils; and

at least one feature pre-formed of material having a thermal conductivity higher than that of the thermally conductive plastic insert molded on at least one of the end coils when the plastic is molded so that it is disposed on an outer surface of the end coil.

2. The armature of claim 1 wherein the feature includes at least one end cap.

3. The armature of claim 2 wherein the feature further includes a fan.

4. The armature of claim 1 wherein the feature includes fins.

5. The armature of claim 1 wherein the slots of the lamination stack includes slot liners made of thermally conductive plastic.

6. The armature of claim 1 wherein the magnet wires have a layer of heat activated adhesive thereon, the thermally conductive plastic molded around the magnet wires and the heat of the thermally conductive plastic as it is molded activating the heat activated adhesive on the magnet wires and bonding the magnet wires together.

7. The armature of claim 1 wherein at least one fan is formed of the thermally conductive plastic when the thermally conductive plastic is molded to at least partially encase the magnet wires.

8. An electric motor including an armature and a stator, the armature, comprising:

a shaft having a lamination stack thereon;

the lamination stack having a plurality of slots in which magnet wires are wound forming coils having end coils at opposed ends of the lamination stack;

thermally conductive plastic molded around the coils including the end coils; and

at least one feature pre-formed of material having a thermal conductivity higher than that of the thermally conductive plastic insert molded on at least one of the end coils when the plastic is molded so that it is disposed on an outer surface of the end coil.

9. The apparatus of claim 8 wherein the feature includes at least one end cap.

10. The apparatus of claim 9 wherein the feature further includes a fan.

11. The apparatus of claim 8 wherein the feature includes fins.

12. The apparatus of claim 8 wherein the slots of the lamination stack includes slot liners made of thermally conductive plastic.

13. The apparatus of claim 8 wherein the magnet wires have a layer of heat activated adhesive thereon, the thermally conductive plastic molded around the magnet wires and the heat of the thermally conductive plastic as it is molded activating the heat activated adhesive on the magnet wires and bonding the magnet wires together.

14. The apparatus of claim 8 wherein at least one fan is formed of the thermally conductive plastic when the thermally conductive plastic is molded to at least partially encase the magnet wires.

15. A power tool having an electric motor including an armature and a stator, the armature, comprising:

a shaft having a lamination stack thereon;

the lamination stack having a plurality of slots in which magnet wires are wound forming coils having end coils at opposed ends of the lamination stack;

thermally conductive plastic molded around the coils including the end coils; and

at least one feature pre-formed of material having a thermal conductivity higher than that of the thermally conductive plastic insert molded on at least one of the end coils when the plastic is molded so that it is disposed on an outer surface of the end coil.

16. The apparatus of claim 15 wherein the feature includes at least one end cap.

17. The apparatus of claim 16 wherein the feature further includes a fan.

18. apparatus of claim 15 wherein the feature includes fins.

19. The apparatus of claim 15 wherein the slots of the lamination stack includes slot liners made of thermally conductive plastic.

20. The apparatus of claim 15 wherein the magnet wires have a layer of heat activated adhesive thereon, the thermally conductive plastic molded around the magnet wires and the heat of the thermally conductive plastic as it is molded activating the heat activated adhesive on the magnet wires and bonding the magnet wires together.

21. The apparatus of claim 15 wherein at least one fan is formed of conductive plastic when the thermally conductive plastic is molded to at least partially encase the magnet wires.