Electric motor with a heat transfer component, circuit board and a ventilation fan

An electric motor comprising:

• a stator having a sleeve shape;
• a rotor disposed inside the stator;
• a shaft coupled to the rotor and stretching along a central axis of the stator;
• a board case provided on one end side of the stator in a direction along the central axis;
• a circuit board provided on an opposite side of the stator with the board case interposed;
• a heat generating component provided on a mounting surface, which is an opposite surface to a surface of the circuit board oriented to a side of the stator;
• a casing to cover a side of the mounting surface;
• a heat transfer component provided between a facing surface of the casing that faces the circuit board and the heat generating component, wherein
• the board case is provided with an extension portion that extends toward the circuit board and protrudes toward a side of the facing surface farther from the circuit board, and
• the heat transfer component is formed with a first engagement portion with which the extension portion engages;
• and
• an insulation component provided between the heat transfer component and the heat generating component, wherein
• the insulation component is formed with a second engagement portion with which the extension portion engages.