Electronically commutated motor

A fan (20), driven by an electronically commutated motor (21), said motor comprising:

• a permanent-magnet external rotor (22) having a rotor shaft (34);
• an internal stator (50) having a stator lamination stack (52) with stator poles (52′, 52″, 52″′, 52″″) between which respective slots (54′, 54″, 54″′, 54″″) are defined;
• a plastic coating (77) which extends through the slots (54′, 54″, 54″′, 54″″) and, together with the stator lamination stack (52), forms a bearing tube (70) for reception of at least one bearing (72, 76) for journaling of the rotor shaft (34),
• said bearing tube (70) being formed with a first axial extension (90′) configured to engage around, and thereby support, a first rotor bearing (72), wherein
• the rotor shaft (34) comprises, at a first end (35), an abutment (92) between which and an inner ring (72′) of the first rotor bearing (72) is provided an axially extending compression spring (94) that urges said inner ring (72′) in a direction toward a second rotor bearing (76).

A method of making an electronically commutated motor having

• an external rotor;
• an internal stator (50) having a lamination stack (52) with a plurality of poles, defining between them slots (54′, 54″, 54″′, 54″″),
• a plastic coating (77) extending through the slots and forming, together with the lamination stack (52), a bearing tube (70) supporting at least one rolling bearing (72, 76) for journaling a shaft (34) of said external rotor,
• comprising the step of
• fixing said at least one rolling bearing in position, by molding material of said plastic coating (77) around said rolling bearing (72).