Method for pulling a stator winding system into a stator lamination stack

1. A method for pulling a stator winding system of an electric machine into a stator lamination stack of the electric machine, said method comprising:

(a) configuring first and second end parts of a winding tool completely inside a shell section thereof, when viewed radially with respect to a tool axis, for guidance and displacement relative to one another by the shell section in a direction of the tool axis by a shortening section between a smaller and a greater distance from one another, with the shell section formed with tool slots for the windings, with the tool slots running parallel to the tool axis of the winding tool, disposed in a circularly distributed manner about the tool axis and closed toward the tool axis;

(b) winding windings of a number of phases of the stator winding system onto the winding tool as layer windings while the two end parts are at the greater distance from each other,

(c) during winding of the windings, holding winding overhangs of the windings radially within the shell section by guide surfaces of the end parts;

(d) guiding the windings in a transition section from sections of the windings disposed in the tool slots to the winding overhangs held by the first end part by guide elements of the first end part such that, when viewed in a tangential direction about the tool axis, the windings extend over an angle that is smaller than an angle in a region of the shell section;

(e) disposing the winding tool with the windings wound thereon in relation to the stator lamination stack such that the tool axis is aligned with an axis of rotation of the electric machine, the first end part projects into the stator lamination stack, and the tool slots are located at same positions in the radial direction and the tangential direction as those of stator slots of the stator lamination stack, into which stator slots the windings are to be inserted and which stator slots run parallel to the axis of rotation of the electric machine, are disposed in a circularly distributed manner about the axis of rotation and are open toward the axis of rotation, and which stator slots have at their end facing the axis of rotation a gap region which is tapered relative to a rest of the stator slot;

(f) displacing the first and second end parts of the winding tool in a direction of the tool axis such that the first and second end parts are first displaced relative to one another at the smaller distance from one another, and the second end part detaches from the winding overhangs wound onto the second end part, as the first and second end parts are displaced;

(g) pushing the first end part through the stator lamination stack in a direction of the axis of rotation to thereby cause the windings to be pulled into the corresponding ones of the stator slots, with the windings being located with their transition sections in the gap regions of the stator slots, and with the winding overhangs that have been detached from the second end part being guided radially outward by guide bevels, which are disposed on the shell section, and then sliding radially outward along the shell section toward the stator lamination stack;

(h) retracting, with or without moving the first and second end parts to the greater distance from one another, the first end part through the stator lamination stack;

(i) the first end part detaching from the winding overhangs wound onto the first end part before or during retraction; and

(k) bending radially outward the winding overhangs detached from the first end part.

2. The method of claim 1 , further comprising:

mounting the guide surfaces of the first end part of the winding tool in a base part of the first end part to enable displacement of the guide surfaces between a first position, in which the guide surfaces project axially from the base element as viewed in the direction of the tool axis, and a second position in which the guide surfaces are retracted into the base element as viewed in the direction of the tool axis; and

moving the guide surfaces of the first end part from the first position to the second position after the first end part has been pushed through the stator lamination stack, thereby releasing the winding overhangs from the first end part before the first end part is retracted.

3. The method of claim 2 , further comprising:

mounting sliding elements in the base element for radial displacement between a first position in which the sliding elements are retracted into the base element as viewed orthogonally to the tool axis, and a second position in which the sliding elements project radially from the base element as viewed orthogonally to the tool axis; and

bending winding overhangs initially wound onto the guide surfaces of the first end part radially outward by the sliding elements.

4. The method of claim 1 , wherein only the windings of a single phase of the stator winding system are wound onto the winding tool at a time, and further comprising repeatedly executing step (a) to (k) until the windings of all the phases of the stator winding system have been pulled into the stator lamination stack.