Motor assembly

A motor comprising:

• a housing that includes a bottom layer on which a first bearing accommodating surface is formed and a side surface which extends from the bottom layer;
• a rotor assembly that includes a rotation shaft and a rotor which is mounted on an outer circumferential surface of the rotation shaft and is accommodated inside the housing;
• a stator assembly that is accommodated inside the housing and surrounds the rotor;
• a housing cover that is coupled to an upper end of the housing and on which a second bearing accommodating surface is formed at a central portion thereof;
• a flow guide that is seated on an upper side of the housing cover;
• an impeller that is connected to the rotation shaft at an upper side of the flow guide;
• an impeller cover that covers the impeller;
• a first bearing that is accommodated in the first bearing accommodating surface and into which one end of the rotation shaft is inserted;
• and
• a second bearing that is accommodated in the second bearing accommodating surface and into which another end of the rotation shaft is inserted,
• wherein the housing cover includes:
• a cover body on which an opening is formed to be defined as an outer ring;
• a plurality of connection arms that connect the second bearing accommodating surface and an inner edge of the cover body;
• and
• a plurality of guide ribs that downwardly extend from the inner edge of the cover body,
• wherein the second bearing accommodating surface is defined as an inner ring and includes:
• a cylindrical surface;
• and
• a flat surface connecting an upper end of the cylindrical surface, and having a shaft through hole in a center thereof,
• wherein the second bearing is accommodated in a space defined by the cylindrical surface and the flat surface, and
• wherein one end of one of the connection arms is connected to the cylindrical surface and another end of the connection arm is connected to one of the guide ribs.