Electric motor

• US 7,608,954 B2
• Filed: 06/27/2006
• Issued: 10/27/2009
• Est. Priority Date: 06/30/2005
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu General Company Limited (Fujifilm Holdings Corporation)
• Inventors: Yamada, Masaki, Matsuzaki, Hirokazu, Kojima, Tomonori
• Primary Examiner(s): LE, THANH TAM T
• Application Number:
  US11/475,161
• Publication Number:
  US 20070001534A1
• Time in Patent Office: 1,218 Days
• Field of Search: 310/43, 310/45, 310/71, 310/89, 310/194
• US Class Current: 310/89
• CPC Class Codes: H02K 1/14 Stator cores with salient poles
• CPC Class Codes: H02K 1/182 to stators axially facing the rotor, i.e. with axial or conical air gap
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 21/24 with magnets axially facing the armatures, e.g. hub-type cycle dynamos
• CPC Class Codes: H02K 2203/06 Machines characterised by the wiring leads, i.e. conducting wires for connecting the winding terminations
• CPC Class Codes: H02K 2203/12 Machines characterised by the bobbins for supporting the windings
• CPC Class Codes: H02K 2211/03 Machines characterised by circuit boards, e.g. pcb
• CPC Class Codes: H02K 3/524 for U-shaped, E-shaped or similarly shaped cores
• CPC Class Codes: H02K 5/08 Insulating casings
• CPC Class Codes: H02K 7/08 Structural association with bearings

Abstract

A gap surface (225) on which a circuit board (5) for driving control is mounted is provided between a first inner surface (222) and a second inner surface (223), a tip end of a terminal pin (6) is projected in a part of the gap surface (225), and further a first concave portion (228) formed by recessing surroundings of the terminal pin (6) in an axis line direction of the terminal pin is provided in the gap surface (225). Thus, an electric motor can be assembled in a short period of time.

Claims

1. An electric motor, comprising:

a cylindrical synthetic resin compact;

a stator embedded in the synthetic resin compact and including a stator iron core, a winding section, a coil wound on the winding section and having a start end and a termination end, and an insulator for insulating the winding section;

a pair of terminal pins erected on the insulator, and connected to the start end and the termination end of the coil;

a circuit board for driving control; and

a rotor arranged so as to face a teeth surface of the stator, wherein the synthetic resin compact includes;

a first inner surface;

a second inner surface positioned away from the first inner surface in an axial direction of the cylindrical synthetic resin compact and having a diameter greater than that of the first inner surface;

a gap surface provided in a gap between the first and second inner surfaces for mounting the circuit board, the terminal pin penetrating the synthetic resin compact so that a tip portion thereof projects from the gap surface; and

a first concave portion provided on the gap surface so as to surround the terminal pin and concaved in an axis line direction of the terminal pin.

2. The electric motor according to claim 1, wherein the second inner surface is located outside the first inner surface in the axial direction and has a second concave portion provided at a portion adjacent to the terminal pin and recessed in a radial direction of the stator.

3. The electric motor according to claim 2, wherein a width in a circumferential direction of the first concave portion is same as a width in a circumferential direction of the second concave portion.

4. The electric motor according to claim 2, wherein a width in a circumferential direction of the second concave portion is greater than a width in a circumferential direction of the first concave portion.

5. The electric motor according to claim 2, further comprising lid members provided at both ends of the synthetic resin compact, the second concave portion having a width depending on a distance between the lid member and the terminal pin.

6. The electric motor according to claim 1, wherein the synthetic resin compact further includes a convex portion integrally formed on a bottom surface of the first concave portion so as to surround the terminal pin, said convex portion having a height smaller than a depth of the first concave portion.

7. The electric motor according to claim 2, wherein the stator is further provided with an insulating sheet for covering the circuit board, the insulating sheet having a locking claw for fitting in the second concave portion.