Generator motor and electric vehicle using same

A generator motor comprising:

• a stator which is fixed to an inner diameter side of a housing;
• a rotor which is disposed to be opposed to an inner circumferential side of the stator and which is supported by bearings rotatably;
• and armature windings which are wound around teeth of a stator core, which teeth are adjacent to slots;
• wherein:
• a passage through which a cooling medium flows and injection holes which communicate with the passage and which inject the cooling medium at positions opposite to winding ends of the armature windings are provided in each of brackets provided on a shaft of the rotor through the bearings;
• the cooling medium is injected from the injection holes of the brackets disposed on axially opposite sides of the shaft toward the winding ends of the armature windings;
• and
• the flow rate distribution of the cooling medium from the plurality of injection holes is set so that the flow rate of the cooling medium from any of the injection holes is higher as the position of the injection hole is higher above the level of the shaft and wherein:
• the number of injection holes provided at positions opposite to the winding ends of the armature windings is large in a vertically upper portion of each of the brackets and gradually smaller in a portion thereof closer to the level of the shaft.