Air-conditioning blower motor unit
An air-conditioning blower motor unit includes a brushless motor that is controlled by electronic parts arranged on a circuit board. A rotation shaft of the brushless motor that rotates a blower fan is rotatably held by bearing holders. The bearing holders and the circuit board are held by a support disk without overlapping each other. The support disk is held by the bearing holders via a vibration absorber.
1. An air-conditioning blower motor unit configured to rotate a blower fan by a brushless motor including a stator and a rotor, the stator including a plurality of electromagnetic coils formed by winding wires around an insulation member covering a stator core, and the rotor holding a permanent magnet and rotatable along a periphery of the stator, the air-conditioning blower motor unit comprising:
a metal bearing holder holding the stator and rotatably supporting a rotation shaft of the brushless motor;
a circuit board provided with an electronic part configured to control the brushless motor; and
a metal support disk holding the bearing holder and the circuit board at positions that do not overlap each other,
wherein the stator core includes a yoke portion that has an annular shape forming an inner hole, and teeth portions protruding from an outer circumference of the yoke portion radially;
the bearing holder is hollow and includes a first bearing holding member holding the stator, and a second bearing holding member partially inserted into a hollow interior of the first bearing holding member, the bearing holder being smaller in diameter than the yoke portion;
a vibration absorber is externally fitted to the second bearing holding member, and the support disk has a holding hole for fitting the vibration absorber;
the support disk elastically holds the bearing holder via the vibration absorber by sandwiching the vibration absorber externally fitted to the second bearing holding member between the first bearing holding member and the second bearing holding member;
the vibration absorber includes a plurality of fan-shaped portions arranged along a circumferential direction of the rotation shaft;
between adjacent fan-shaped portions, the bearing holder is locked, and end portions of the wires drawn from the electromagnetic coil pass through; and
the end portions of the wires are electrically connected to the circuit board.
2. The air-conditioning blower motor unit according to claim 1 , wherein a clearance is formed between the vibration absorber and the insulation member.
3. The air-conditioning blower motor unit according to claim 1 , wherein the fan-shaped portions protrude from an outer wall in a middle of a thickness direction of the vibration absorber, have a larger diameter than the bearing holder, and have one end surface in contact with one end surface of the yoke portion.
4. The air-conditioning blower motor unit according to claim 3 , wherein the vibration absorber includes a first vibration absorber formed by an annular body, and a second vibration absorber formed by an annular body provided with the fan-shaped portions, the second vibration absorber is larger in diameter than the first vibration absorber.
5. The air-conditioning blower motor unit according to claim 4 , wherein the second bearing holding member includes radial protrusion portions protruding radially outwardly, and the radial protrusion portions are locked with a portion between the adjacent fan-shaped portions.
6. The air-conditioning blower motor unit according to claim 5 , wherein a plurality of passage holes are recessed radially outwardly from an inner wall of the holding hole of the support disk and overlapped with the portion between the adjacent fan-shaped portions,
a stator side terminal portion protruding toward the support disk grips the end portions of the wires and is embedded in the insulation member,
the stator side terminal portion and the radial protrusion portions pass through the passage holes and are guided out toward the first vibration absorber, and
lower ends of the radial protrusion portions guided out enter an inner surface of the first vibration absorber, and a bus bar unit formed on the circuit board at a position facing an outer surface of the first vibration absorber and the stator side terminal portion are electrically connected on the outer surface of the first vibration absorber.
7. The air-conditioning blower motor unit according to claim 6 , wherein the support disk is fixed to a first casing member or a second casing member, and positioned at a hollow interior of a casing formed by the first casing member and the second casing member,
the support disk, the circuit board directly held by the support disk, the bearing holder elastically held by the support disk via the first vibration absorber and the second vibration absorber, and the brushless motor fixed to the bearing holder are accommodated in the hollow interior of the casing.