Patent ID: 8683673
Filing Date: 2014-04-01
Classification: H02K,Y10T

Abstract:
1. A stator manufacturing method for manufacturing a stator for a rotary electric machine, the stator having a stator core including an outer cylinder with a cylindrical through bore formed through an axial direction of the outer cylinder and a core assembly shrink-fit in the through bore of the outer cylinder, the core assembly being equipped with segment cores wound by coils, the method including: a step of providing a guide unit operatively associated with the stator core and comprising a large-diameter portion having a bore defined by a diameter larger than an outer diameter of the core assembly, and a small-diameter portion having an end serving as the one end of the guide unit and a bore defined by a diameter i) larger than the inner diameter of the outer cylinder given when the outer cylinder is not heated in the heating step, ii) smaller than the inner diameter of the outer cylinder given when the outer cylinder is heated in the heating step, and iii) smaller than the outer diameter of the coil assembly, wherein both bores of the large-diameter and small-diameter portions are connected via a tapered through hole to be in line in a direction along the tapered through hole, the tapered through hole being shaped by a tapered surface connecting both surfaces respectively shaping both of the bores of the large-diameter and small-diameter portion; a step of heating the outer cylinder to a predetermined temperature so that the outer cylinder is thermally expanded to increase an inner diameter of the outer cylinder; a step of locating the guide unit such that one end of the guide unit is adjacent to the outer cylinder and both of the guide unit and the outer cylinder are in line with each other in the axial direction, after the temperature of outer cylinder reaches the predetermined temperature in the heating step; a step of forcibly inserting the core assembly through the guide unit and then inserting the core assembly into the outer cylinder in a state where the outer cylinder has been heated to the predetermined temperature in the heating step; and a first step of cooling the outer cylinder to reduce the diameter thereof, immediately after the inserting step is completed.