Electrical insulation particularly for use in winding slots of dynamo-electric machines and method for its manufacture

• US 3,974,314 A
• Filed: 03/20/1974
• Issued: 08/10/1976
• Est. Priority Date: 03/29/1973
• Status: Expired due to Term

• Current Assignee: Micafil AG
• Original Assignee: Micafil AG
• Inventors: Fuchs, Heinz
• Primary Examiner(s): McCamish, Marion E.
• Assistant Examiner(s): Lipsey, Charles E.
• Application Number:
  US05/453,169
• Time in Patent Office: 874 Days
• Field of Search: 161/79, 161/82, 161/92, 161/93, 161/161, 161/184, 161/185, 161/197, 161/227, 161/DIG. 4, 174/110 N, 174/121 R, 174/121 SR, 174/138 E, 156/306, 156/309, 310/45, 310/215, 428/212, 428/236, 428/251, 428/268, 428/273, 428/282, 428/285, 428/286, 428/287, 428/74, 428/302, 428/317
• US Class Current: 428/212
• CPC Class Codes: B29C 70/00 Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
• CPC Class Codes: B29K 2309/08 Glass
• CPC Class Codes: B32B 2260/023 Two or more layers
• CPC Class Codes: B32B 2260/046 Synthetic resin
• CPC Class Codes: B32B 2305/08 Reinforcements
• CPC Class Codes: B32B 2305/80 Sintered
• CPC Class Codes: B32B 2307/206 Insulating
• CPC Class Codes: B32B 38/08 Impregnating
• CPC Class Codes: B32B 5/26 another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: H01B 3/48 fibrous materials fibre-reinforced plastics H01B3/47
• CPC Class Codes: Y10S 174/13 High voltage cable, e.g. above 10kv, corona prevention
• CPC Class Codes: Y10S 174/19 in a dynamo-electric machine
• CPC Class Codes: Y10T 428/24942 including components having same physical characteristic in differing degree
• CPC Class Codes: Y10T 428/249959 Void-containing component is wood or paper
• CPC Class Codes: Y10T 428/24999 Inorganic
• CPC Class Codes: Y10T 428/31739 Nylon type
• CPC Class Codes: Y10T 442/3691 Fabric layer contains glass strand material

Abstract

A laminated molded insulation material for insulation of electrical machines and particularly useful for conductor slot insulation of dynamo-electric machines is produced by covering both sides of a dielectrically strong, homogeneous electrically insulating polyheterocylene foil such as polyhydantoin with protective layers of tangled fibers such as an aromatic polyamide paper known under the trade name "Nomex". The composite consisting of the protective tangled fiber layers joined to the insulating foil is then enclosed on both sides by layers of a high-tensile strength, fiber-reinforced synthetic resin using, for example, a glass fleece or glass-silk fabric as the fiber material, and which are joined to the protective tangled fiber layers and in such manner that within the protective layers opposite the insulating foil there exists a continuous remainder of non-resin impregnated tangled-fiber structure consisting solely of tangled fibers.

Claims

1. A stiff multi-layer laminated molded structure for use as electrical insulation in electrical machines and particularly for use in slot insulation which comprises a continuous inner planar layer constituted by a dielectrically strong temperature stable homogeneous insulating synthetic resin foil, an intermediate tangled fiber planar layer coextensive with and adhered to each side of said insulating synthetic resin foil by means of a thermosetting synthetic resin binding agent and an outer thermosetting glass fiber reinforced synthetic resin planar layer coextensive with and adhered to each of said intermediate tangled fiber layers, said resin binding agents penetrating only the surface portions of each of said tangled fiber layers thereby leaving within each of the latter a core portion free from the binding agent for protecting said inner insulating synthetic resin foil against cracking due to imposed stresses.