Electric motor with plastic encapsulated stator

• US 4,048,530 A
• Filed: 05/05/1975
• Issued: 09/13/1977
• Est. Priority Date: 05/05/1975
• Status: Expired due to Term

• Current Assignee: The Superior Electric Co.
• Original Assignee: The Superior Electric Co.
• Inventors: Kaufman, George A. Jr.
• Primary Examiner(s): Duggan, Donovan F.
• Application Number:
  US05/574,356
• Time in Patent Office: 862 Days
• Field of Search: 310/43, 310/90, 310/254, 310/89
• US Class Current: 310/89
• CPC Class Codes: H02K 5/04 Casings or enclosures characterised by the shape, form or construction thereof
• CPC Class Codes: H02K 5/08 Insulating casings
• CPC Class Codes: H02K 5/15 Mounting arrangements for bearing-shields or end plates
• CPC Class Codes: H02K 5/1732 radially supporting the rotary shaft at both ends of the rotor H02K5/1737 takes precedence

Abstract

An electric motor having a stator and a rotor in which the stator is formed with an encapsulating hardened plastic shell formed with a through aperture in which the rotor is positioned and which has portions that accurately concentrically support the motor with respect to the stator.

Claims

1. An electric motor comprising a stator and a rotor;

said stator including a tubular stack of laminations having an axis, winding means positioned on said stack and a hardened plastic covering encapsulating said stack and windings and being formed to provide a through opening aligned with the stack axis;

said rotor having portions disposed within the opening and an axis; and

support means positioned at each end of the stack including means integral with the plastic covering for supporting the rotor essentially coaxially in the stator and means for securing the integral means to the hardened plastic covering with the covering constituting the sole structure for securing the integral means to the stack to prevent movement of the integral means transverse to the axis of the stator stack and outwardly therefrom, in which the integral means of the support means includes at least a metal insert formed with a through hole positioned adjacent an end portion of the opening and being adhered to the covering, in which the insert has an inner surface transverse to the axis, in which the stator stack has an adjacent surface and in which the inner surface and the adjacent surface abut at the outer periphery of the stack and insert, in which the insert includes a substantial exposed portion extending diametrically along one end surface of the stator, in which the insert and covering are formed to have cooperating mechanically interlocking portions, in which the support means includes another insert having an inner surface transverse to the stator axis, in which the stator stack has an adjacent surface transverse to the stator axis, in which the inner surface of the another insert and its adjacent stack surface are spaced apart with covering material being positioned therebetween for solely supporting the insert, in which the stator stack is formed to have inwardly extending poles having inner faces that define a portion of the through opening, in which the poles are spaced from each other, in which the covering material fills the spaces between the poles to occupy all of the interior of the stator that is unoccupied by the other parts of the stator, in which the covering material in the spaces extends for the complete length of the stator stack to interconnect both support means, in which the support means further includes a bearing positioned adjacent each end of the through opening for rotatably supporting the rotor and in which there are cooperating means on the stator and rotor for limiting axial movement of the rotor with respect to the stator.