A stator (50, 50A) having a central axis, the stator comprising: a core having a cylindrical portion and a plurality of teeth radially inwardly extending toward the central axis; an insulator (20, 20A) placed on an axial end surface of the core; a plurality of coil windings, the coil windings each wound around one of the teeth; lead wires extending from both ends of each of the coil windings; and a yarn securing the lead wires on to the insulator; the insulator having: an outer wall surrounding the central axis and erected in such a way as to axially extend away from the axial end surface; a plurality of teeth cover portions each extending radially inwardly from the outer wall toward the central axis and having a base; and a plurality of inner walls, the inner walls each being erected at and extending axially from a distal end portion of each of the teeth cover portions, the coil windings being placed on the corresponding teeth cover portions and between the outer wall and the corresponding inner walls, the lead wires being placed on the coil windings between the outer wall and the corresponding inner walls; and a passage portion formed in at least one of the teeth cover portions, the passage portion radially extending and being formed to pass the yarn therethrough, and the passage portion being spaced from the coil windings; wherein a notch to engage with the yarn is formed at a location above the passage portion in the outer wall; a groove and a notch are disposed in each inner wall; the notch of the outer wall is formed at a location at an upper end of the outer wall corresponding to the base of each tooth cover portion; and the yarn passes through the corresponding groove and notch in the corresponding inner wall, and engages with the corresponding notch at the upper end of the outer wall. a core having a cylindrical portion and a plurality of teeth radially inwardly extending toward the central axis; an insulator (20, 20A) placed on an axial end surface of the core; a plurality of coil windings, the coil windings each wound around one of the teeth; lead wires extending from both ends of each of the coil windings; and a yarn securing the lead wires on to the insulator; the insulator having: an outer wall surrounding the central axis and erected in such a way as to axially extend away from the axial end surface; a plurality of teeth cover portions each extending radially inwardly from the outer wall toward the central axis and having a base; and a plurality of inner walls, the inner walls each being erected at and extending axially from a distal end portion of each of the teeth cover portions, the coil windings being placed on the corresponding teeth cover portions and between the outer wall and the corresponding inner walls, the lead wires being placed on the coil windings between the outer wall and the corresponding inner walls; and an outer wall surrounding the central axis and erected in such a way as to axially extend away from the axial end surface; a plurality of teeth cover portions each extending radially inwardly from the outer wall toward the central axis and having a base; and a plurality of inner walls, the inner walls each being erected at and extending axially from a distal end portion of each of the teeth cover portions, the coil windings being placed on the corresponding teeth cover portions and between the outer wall and the corresponding inner walls, the lead wires being placed on the coil windings between the outer wall and the corresponding inner walls; and a passage portion formed in at least one of the teeth cover portions, the passage portion radially extending and being formed to pass the yarn therethrough, and the passage portion being spaced from the coil windings; wherein a notch to engage with the yarn is formed at a location above the passage portion in the outer wall; a groove and a notch are disposed in each inner wall; the notch of the outer wall is formed at a location at an upper end of the outer wall corresponding to the base of each tooth cover portion; and the yarn passes through the corresponding groove and notch in the corresponding inner wall, and engages with the corresponding notch at the upper end of the outer wall.