Stator unit, motor, and method of manufacturing stator unit
A stator unit included in a motor includes a base member, an armature, a circuit board, and a mold resin portion. The base member extends substantially perpendicularly to a vertically extending center axis. The armature and the circuit board are positioned above the base member. The circuit board is electrically connected to the armature. The mold resin portion covers the armature and the circuit board. In a process of forming the mold resin portion, the base member is firstly supported by a first mold.
1. A stator unit included in a motor, the stator unit comprising:
a base member extending substantially perpendicularly to a center axis extending vertically;
an armature positioned above the base member;
a circuit board positioned above the base member and electrically connected to the armature; and
a mold resin portion covering the armature and the circuit board,
wherein the base member has an elastic member on a radially outer side with respect to the circuit board in plan view,
at least part of the elastic member is positioned on the radially outer side with respect to the mold resin portion,
the elastic member has an annular shape that is centered at the center axis, and
the mold resin portion is provided on a radially inner side with respect to an outer edge of the elastic member, with an outer periphery of the mold resin portion overlapping at least part of the elastic member in plan view.
2. The stator unit according to claim 1 ,
wherein at least part of the elastic member project from an upper surface of the base member.
3. The stator unit according to claim 1 ,
wherein the elastic member is one of a plurality of elastic members provided on the base member, and
wherein the plurality of elastic members are centered at the center axis and have different diameters.
4. The stator unit according to claim 1 ,
wherein the elastic member is a ring-shaped resin member.
5. The stator unit according to claim 1 ,
wherein the base member has a groove in an upper surface, the groove being positioned on the radially outer side with respect to the circuit board, and
wherein part of the elastic member is fitted in the groove.
6. The stator unit according to claim 1 , further comprising:
adhesive interposed between an upper surface of the base member and the elastic member.
7. The stator unit according to claim 1 ,
wherein the base member has an annular wall portion on an upper surface, and
wherein the elastic member is positioned on an upper surface of the wall portion.
8. The stator unit according to claim 1 ,
wherein the elastic member is positioned on a radially inner side with respect to a peripheral edge of an upper surface of the base member.
9. The stator unit according to claim 1 ,
wherein the mold resin portion has a gate resultant on an outer peripheral surface.
10. The stator unit according to claim 9 ,
wherein the gate resultant is positioned below the circuit board in an axial direction and above the base member in the axial direction.
11. The stator unit according to claim 1 ,
wherein the mold resin portion has a gate resultant on a lower surface.
12. The stator unit according to claim 11 ,
wherein the base member has a through hole extending through the base member in the axial direction, and
wherein the gate resultant is provided at a position of the lower surface of the mold resin portion that is within the through hole in plan view.
13. The stator unit according to claim 1 , further comprising:
a bearing housing having a cylindrical shape extending along the center axis,
wherein the armature is fixed to an outer peripheral surface of the bearing housing, and
wherein the base member is positioned below the armature and is fixed to the outer peripheral surface of the bearing housing.
14. The stator unit according to claim 13 ,
wherein the bearing housing is made of metal.
15. The stator unit according to claim 13 ,
wherein the bearing housing is made of resin.
16. A motor comprising:
the stator unit according to claim 1 ; and
a rotor unit supported in such a manner as to be rotatable about the center axis and having pole faces that each face the armature in a radial direction.