Rotor mechanism of rotating electrical machine and method of manufacturing same

#The present invention relates to a rotor mechanism that functions as a rotor or an armature of a rotating electrical machine such as an electrical motor and a method of manufacturing such a rotor mechanism, and more particularly relates to a rotor mechanism of a rotating electrical machine suitable for fastening a core and a shaft and a method of manufacturing such a rotor mechanism.

#JP2006-187063A discloses, as a fastening mechanism of a core and a shaft in which a large number of electromagnetic steel sheets constituting a rotor of a rotating electrical machine are stacked in layers, a fastening mechanism in which end plates arranged on both side surfaces of the core are directly pressed into the shaft and fixed thereto.

#This is achieved by a mechanism in which a collar is interposed between the core and the shaft that are constituent elements of the rotor and in which the shaft and the collar, and the collar and core are pressed and fastened with a predetermined clearance. On both side surfaces of the core, the end plates directly pressed into the shaft are arranged. When the core and the end plates are formed with a silicon steel sheet and the shaft is formed with a steel rod, the collar is formed of a non-ferrous metal material such as a magnesium alloy that has a higher linear expansion coefficient than at least the core and the shaft. Thus, even if the individual elements are thermally expanded under a high temperature environment, a clearance of the collar with respect to the shaft in a direction in which a diameter is reduced is acquired.

#FIG. 1 is a schematic configuration diagram of a rotor mechanism of a rotating electrical machine showing an embodiment of the present invention;

#FIG. 2 is an illustrative diagram showing a step of manufacturing the rotor mechanism of the rotating electrical machine;

#FIG. 3 is an illustrative diagram showing a step of manufacturing the rotor mechanism of the rotating electrical machine, subsequent to FIG. 2;

#FIG. 1 is a cross-sectional view showing an embodiment of a rotor mechanism of a rotating electrical machine according to the present invention. In FIG. 1, the rotor mechanism of the rotating electrical machine includes a cylindrical core 1, disc-shaped end plates 2 and 3 arranged on both sides of the core 1, a rotor shaft 4 that inserts through and supports the core 1 and the end plates 2 and 3, and a crimp retainer 5 that locates and fixes the core 1 and the end plates 2 and 3 on the rotor shaft 4.

#The rotor shaft 4 is cylindrical, includes, in an inner circumferential portion of a cylindrical portion, a flange 41 extending in an inner circumferential direction, is fastened through the flange 41 to an unillustrated drive shaft and is formed rotatably together with the drive shaft. The outside diameter of the rotor shaft 4 is formed to be substantially equal to the inside diameter of the core 1. In an outer circumferential portion of a region of the rotor shaft 4 supporting the core 1 on one side in the axial direction, a protrusion portion 42 that supports the end plate 3 on the other side is formed around the entire circumference. In the outer circumferential portion of the region of the rotor shaft 4 supporting the core 1 on the other side in the axial direction, a crimp groove 43 engaging with the crimp retainer 5 is formed around the entire circumference. The crimp groove 43 may not be provided on the entire circumference, and may be provided partially in the circumferential direction. In the example shown in the figure, the outer circumferential portion of the rotor shaft 4 has a smaller diameter outwardly of a portion (away from the support region of the core 1) where the crimp groove 43 is arranged.

#The protrusion portion 42 is formed in a stepped shape with a small-diameter portion 44 and a large-diameter portion 45. The small-diameter portion 44 is adjacent to the region supporting the core 1 and protrudes from the outer circumferential portion of the rotor shaft 4 to the outer circumference in the radial direction, the large-diameter portion 45 is formed to protrude, in an outside connecting (away from the support region of the core 1) to the small-diameter portion 44 in the axial direction, from the outer circumferential portion of the rotor shaft 4 to the outer circumference in the radial direction.