# US 2009/0260218 A1 · Method for manufacturing a stator for inner-rotor type rotary electric machines > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2009/0260218 A1 - Document ID: US20090260218A1 - Status: Published application - Kind: A1 - Application number: 12/427,160 - Filed: 2009-04-21 - Published: 2009-10-22 - Earliest claimed: 2008-04-21 - Assignees: Denso Corporation - Inventors: Akito Akimoto; Masaomi Dobashi - Web page: https://patentgrep.com/patent/US20090260218A1 ## CPC - H02K 3/12: arranged in slots - H02K 15/066: inserted perpendicularly to the axis of the slots or inter-polar channels - Y10T 29/49009: Dynamoelectric machine - Y10T 29/49012: Rotor - H02K: DYNAMO-ELECTRIC MACHINES (dynamo-electric relays H01H53/00; conversion of DC or AC input power into surge output power {H03K3/53}) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract A tapered cage coil is prepared, having a small-diameter top coil end 101 and a large-diameter base coil end. The tapered cage coil is axially inserted into a stator core. Then, the tapered cage coil is radially expanded to thrust slot-accommodated portions of the coil into slots of the stator core. This can eliminate the necessity of deforming the base coil end to thereby facilitate the manufacturing procedures. At the same time, possible spring back can be mitigated. ## Claims ### Claim 1 A method for manufacturing a stator for an inner-rotor type rotary electric machine comprising: a stator core having an inner peripheral surface in which a number of slots are circumferentially provided at a predetermined pitch; and a tapered cage coil consisting of a distributed-winding coil having a number of slot-accommodated portions to be accommodated in the slots, the slot-accommodated portions being arranged at a predetermined circumferential pitch and positioned being radially apart from the axis by a predetermined distance, the tapered cage coil having a top coil end and a base coil end each of which is made up of a group of coil end portions, each coil end portion connecting two adjacent slot-accommodated portions to be radially projected from two adjacent slots which are distanced from each other by an electrical angle of “π”, wherein the method comprises steps of: preparing the tapered cage coil that includes the top coil end having a diameter smaller than that of the inner peripheral surface of the stator core, the base coil end having a diameter larger than that of the inner peripheral surface of the stator core, and the slot-accommodated portions which are provided being inclined from the top coil end to the base coil end so that a distance from the axis is increased toward the base coil end; starting axial insertion of the tapered cage coil into the stator core, with the top coil end being inserted first; individually inserting the slot-accommodated portions, during the axial insertion, into the slots from respective openings of the slots; stopping the axial insertion after the top coil end has projected from an end face of the stator core; and thrusting the slot-accommodated portions into the slots by axially compressing the top coil end while the slot-accommodated portions are plastically deformed in the axially outward direction, to shape the tapered cage coil into a completed form of the tapered cage coil. ### Claim 2 (depends on 1) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 1, further comprising steps of: preparing a circumferentially expanded wave-winding coil by bending a linear conductor wire into a wave pattern in which a base coil end portion configuring the base coil end, the slot-accommodated portion corresponding to a forward slot-accommodated portion, a top coil end portion configuring the top coil end, and the slot-accommodated portion corresponding to a return slot-accommodated portion are sequentially connected; preparing a circumferentially expanded stator coil by combining the circumferentially expanded wave-winding coils equivalent to the number of phases; and preparing the tapered cage coil by curling up the circumferentially expanded stator coil into a cylindrical shape. ### Claim 3 (depends on 1) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 1, wherein the tapered cage coil is made up of an insulation-coated flat conductor wire. ### Claim 4 (depends on 1) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 1, wherein the top coil end of the tapered cage coil is projected in the axial direction more than the base coil end of the tapered cage coil. ### Claim 5 (depends on 2) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 2, wherein: each of the top coil end portions of the circumferentially expanded wave-winding coil is formed to have a circumferential expansion width smaller than that of each of the base coil end portions of the circumferentially expanded wave-winding coil; each of the top coil end portions of the circumferentially expanded wave-winding coil is formed to have an axial projection length larger than that of each of the base coil end portions of the circumferentially expanded wave-winding coil; and the slot-accommodated portions of the circumferentially expanded stator coil are extended at a certain inclination with respect to a direction in which the circumferentially extended stator coil is extended, the direction corresponding to a direction perpendicular to the axial direction. ### Claim 6 (depends on 5) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 5, wherein the circumferentially expanded wave-winding coil is wrapped about a tapered jig, the jig having grooves axially extended, being communicable with openings of the slots of the stator core, and guide plates axially outwardly extended, being positioned on circumferentially lateral sides of each of the grooves, so that the slot-accommodated portions can be inserted into the grooves to prepare the tapered cage coil. ### Claim 7 (depends on 1) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 1, wherein the slot-accommodated portions of the tapered cage coil are linearly provided from the top coil end to the base coil end at a certain inclination. ### Claim 8 (depends on 1) The method for manufacturing a stator for an inner-rotor type rotary electric machine according to claim 1, wherein, of the slot-accommodated portions of the tapered cage coil, a portion near the top coil end has a relatively larger inclination with respect to the axial direction, compared with a portion near the base coil end.