Motor structure and their manufacturing method

• US 6,407,472 B1
• Filed: 08/24/1999
• Issued: 06/18/2002
• Est. Priority Date: 05/19/1997
• Status: Expired due to Fees

• Current Assignee: Minebea Company Limited (MinebeaMitsumi Inc.)
• Original Assignee: Minebea Company Limited (MinebeaMitsumi Inc.)
• Inventors: Takayanagi, Shinichi
• Primary Examiner(s): Ramirez, Nestor
• Assistant Examiner(s): LE, DANG D
• Application Number:
  US09/382,115
• Publication Number:
  US 20020047331A1
• Time in Patent Office: 1,029 Days
• Field of Search: 310/45, 310/216, 310/217, 310/254, 310/258, 310/259, 310/43, 295/96, 295/921, 296/09, 427/104, 427/58, 336/210-213, 336/216-219, 336/233, 336/234
• US Class Current: 310/45
• CPC Class Codes: H02K 1/187 to inner stators
• CPC Class Codes: H02K 15/12 Impregnating, heating or drying of windings, stators, rotors or machines
• CPC Class Codes: H02K 3/30 Windings characterised by the insulating material
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine

Abstract

The motor structure, which has a laminated structure of plural plates 1 and also has a stator pole assembly 10 formed with a component mounting portion, comprises a synthetic resin layer 6 which encloses and covers the plural plates 1 while holding the plates in a closely contacted state, overhang portions (8, 9) integral with the synthetic resin layer 6 and which serve to not only hold but also position motor components, and an insulating film 7′ which covers portions not coated with the synthetic resin. While the synthetic resin layer is formed on the surface of the lamination stack, pressure is applied to the laminated plates as constituents of the stator pole assembly from both upper and lower surfaces of the laminate. This application of pressure is performed using plate pressing projections formed in the mold.

Claims

1. A method for manufacturing a motor structure having a laminated structure of a plurality of plates and a stator pole assembly formed with a component mounting portion, comprising:

preparing a plurality soft iron plates each having an annular yoke portion, and a plurality of stator pole portions which project radially outwardly from the yoke portion and stator pole teeth formed at an end portion of each stator pole portion;

stacking the plurality of soft iron plates;

setting the stacked soft iron plates into a mold;

pressing both upper and lower surfaces of the stacked soft iron plates by protrusions which are formed in the mold;

injection molding a synthetic resin into the mold to cover a portion of the stacked soft iron plates including an outer peripheral surface of the stator pole teeth, and binding the stacked soft iron plates to each other with the synthetic resin layer and integrally forming a circular groove and a projection formed integrally with the synthetic resin layer to hold and position components of the motor, the circular groove being located at a first end of the inside of the yoke portion, and receiving a motor hub component of the motor, and the projection being formed circularly and being located on a second end of the inside of the yoke portion, opposite the first end of the inside of the yoke portion, a center of the projection forming a hole to communicate the interior of the hole with the circular groove, and the projection fitting into a positioning hole in a substrate to position the pole assembly into the substrate ; and

covering a portion of the stacked soft iron plates not covered with the synthetic resin layer with an insulting film.

2. A method for manufacturing a motor structure according to claim 1, wherein said protrusions press on the stator pole teeth portions and the yoke portion during molding.

3. A method for manufacturing a motor structure according to claim 1, further comprising forming said insulating film with an electrode position coating.

4. A method for manufacturing a motor structure according to claim 1, further comprising forming said insulating film with a spray coating.

5. A method for manufacturing a motor structure according to claim 1, further comprising forming said insulating film thinner than said synthetic resin layer.

6. A method for manufacturing a motor having a stator pole assembly formed with a component mounting portion, comprising:

stacking a plurality soft iron plates, each of said soft iron plates having an annular yoke portion, a plurality of stator pole portions which project radially outwardly from the yoke portion, and stator pole teeth formed at an end portion of each stator pole portion;

setting the stacked plurality of soft iron plates into a mold;

pressing upper and lower surfaces of the stacked soft iron plates by protrusions formed in the mold;

injecting a synthetic resin into the mold to cover a portion of the stacked soft iron plates including an outer peripheral surface of the stator pole teeth, and to bind the stacked soft iron plates to each other with synthetic resin layers while integrally forming a projection portion with the synthetic resin layer for positioning the stator pole assembly; and

covering any portion of the stacked soft iron plates not covered with the synthetic resin layer with an insulating film.

7. A method for manufacturing a motor structure having a laminated structure of a plurality of plates and a stator pole assembly formed with a component mounting portion, comprising:

preparing a plurality soft iron plates each having an annular yoke portion, and a plurality of stator pole portions which project radially outwardly from the yoke portion and stator pole teeth formed at an end portion of each stator pole portion;

stacking the plurality of soft iron plates;

setting the stacked soft iron plates into a mold;

pressing both upper and lower surfaces of the stacked soft iron plates by protrusions which are formed in the mold;

p1 injection molding a synthetic resin into the mold to cover a portion of the stacked soft iron plates including an outer peripheral surface of the stator pole teeth, and binding the stacked soft iron plates to each other with the synthetic resin layer and integrally forming a projection portion with the synthetic resin layer for positioning the stator pole assembly; and

covering a portion of the stacked soft iron plates not covered with the synthetic resin layer with an insulting film.