Electric motor having sealed casing and manufacturing method thereof

Abstract

Provided are, an electric motor assembly capable of preventing a sealant from leakage through a lead-wire drawing portion, and an electric motor manufacturing method with use of the electric motor assembly. The electric motor assembly includes a rotor, a stator, a casing, a partition wall with through-holes, plugs made of a highly elastic material and including a tapered outer peripheral surface to be fitted into the through-holes, and lead wires connected to the stator. The plugs surround lead-wire insertion holes. A sealant is injected into the casing in a state that the lead wires are drawn through the lead-wire insertion holes. The injection pressure presses the plugs outwardly to bring the outer peripheral surfaces of the plugs into close contact with the inner peripheral surface surrounding the through-holes and elastically deforms the plugs in a diameter-reduction direction to cause the plugs to close the lead-wire insertion holes.