The present disclosure is directed to slotless electric motor, in particular, to a method of manufacturing a stator for a slotless electric motor. An aspect of the disclosure provides a method of manufacturing a stator for a slotless electric motor, the method comprising: disposing a conductor in the shape of an annular cylinder; bonding a plurality of bonded lengths of the conductor, wherein the plurality of bonded lengths are separated by non-bonded lengths; folding the conductor to provide a plurality of petals repeated along the conductor, wherein each petal comprises a pair of bonded lengths connected by a non-bonded length; rotating each petal about a point on the second circle to align in parallel the bonded lengths of all of the petals to thereby provide a stator comprising a cylindrically-shaped conductor wherein the bonded lengths are equidistantly disposed around and from a central longitudinal axis of the cylindrically-shaped conductor.

A coil molding apparatus being capable of easily forming the band-shaped coil into a wound state, without the winding posture in the coil winding jig being disturbed by spring back of the band-shaped coil. The coil molding apparatus includes: a coil winding jig for winding the band-shaped coil with inserting straight portions thereof into a plurality of comb-shaped grooves in the outer periphery; a coil conveying mechanism unit for pivotally conveying the band-shaped coil along the outer periphery of the coil winding jig; and guide members for inserting the band-shaped coil into the plurality of comb-shaped grooves by guiding in an arc shape while contacting with the side end of the band shaped groove thereby gradually reducing in diameter accompanying pivoting at a second half portion of pivot conveying of the band-shaped coil, then extending with maintaining curvature of the oprtion of which the diameter has already been reduced.

A coil forming apparatus is configured so as to, upon forming a band-shaped coil having side ends at both ends of a plurality of straight portions, in the course of pivotally conveying the band-shaped coil along the outer circumference of a coil winding jig by a coil conveying mechanism, sandwich the side end by a reforming portion of guide member, reform the band-shaped coil into an arc shape, then insert a plurality of the straight portion into a respective one of the plurality of comb-shaped grooves with reducing a diameter of guiding transfer way of the guide member while pressing a steady laminated part of the band-shaped coil in sliding contact manner, thereby inserting a plurality of the straight portion into a respective one of the plurality of comb-shaped grooves, possible of easily forming the band-shaped coil into a precisely wound state.

Certain aspects relate to a continuous winding formed from a conductor of rectangular cross-section, the winding having a compound bend in the crowns connecting successive linear segments where the compound bend does not stress the conductor insulation to its failure point. The compound bend can be formed by applying force to the conductor in a first direction, thereby shaping a first bend in the conductor to form a u-shaped conductor having a crown and two linear segments, where the crown includes a v-shaped bend and two straight segments on either side of the v-shaped bend that each connect to one of the linear segments. A second bend can be formed by applying force to the conductor in a second direction perpendicular to the first direction. The shape of the second bend can depend on the desired radius of the winding when circularly wound and positioned in a stator.

A multi-conductor winding for an electric machine includes a plurality of conductors having a substantially identical wire form with a plurality of end turns joining a plurality of slot segments. A first portion of the plurality of conductors is arranged in a first orientation and a second portion of the plurality of conductors is arranged in a second orientation that is a mirror image of the first orientation. The plurality of end turns of the plurality of conductors includes at least three distinct winding pitches.

Provided are a clamp jig for inhibiting an increase in the size of clamping equipment, and reducing the load during clamping by clamping after doing preliminary aligning of a segment end part; a stator manufacturing device; and a method for manufacturing a stator. The clamp jig 40 has a pair of clamp bodies 41, extended in a stator core radial direction, for clamping from both sides in the stator core circumferential direction the end part of an electric conductor, which is inserted in the stator core and welded; and a convex part 42 provided extending in the stator core axis direction at the bottom of the clamp body 41, the convex part being inserted between unwelded electric conductors.

A method for producing a winding for a stator of an electric rotating machine, the stator itself, a method for producing the stator, and an electric rotating machine. In the method for producing a winding for a stator of an electric rotating machine, a plurality of conductors are provided and are wound on a first fin along a first winding direction, so that the conductors loop around the first fin, and the first fin is then removed from the resultant winding of the conductors.

A method of forming a winding for an electric machine includes forming a plurality of conductors having a substantially identical wire form with a plurality of end turns joining a plurality of slot segments, defining a first portion of the plurality of conductors as first conductors, rotating a second portion of the plurality of conductors about a central axis to mirror the first conductors, defining the second portion of the plurality of conductors as second conductors, combining select ones of the first conductors and select ones of the second conductors to form conductor pairs, and combining a plurality of conductor pairs to form a multi-conductor winding.

The invention proposes a stator for a rotating electric machine, in particular for a motor vehicle, the stator (15) including: —a body (27) including notches (37) that are opened radially into an internal wall (40) of said body, —at least one winding (43) forming a phase of the stator, the winding formed from turns (54) includes a first half-phase (49) and a second half-phase (50) that are superposed radially in the notch (37), each turn including a series of axial strands (44) that are received in a series of associated notches and connecting strands (45, 46) that connect the successive axial strands (44) by extending alternatively to protrude with respect to the body (27). A length of wire of each turn of one of the half-phases is larger than the length of wire of each turn of the other half-phase. Furthermore, one of the half-phases has a number of turns higher than that of the other half-phase.

A multi-conductor winding for an electric machine includes a plurality of conductors having a substantially identical wire form with a plurality of end turns joining a plurality of slot segments. A first portion of the plurality of conductors is arranged in a first orientation and a second portion of the plurality of conductors is arranged in a second orientation that is a mirror image of the first orientation. The plurality of end turns of the plurality of conductors includes at least three distinct winding pitches.