Stator of electric rotating machine

This application is related to Japanese Patent Application No. 2008-109549 filed on Apr. 18, 2008, the contents of which are hereby incorporated by reference.

1. Field of the Invention

The present invention relates to a stator of an electric rotating machines and an electric rotating machine having the stator.

2. Description of Related Art

In recent years, there is a growing need of electric rotating machines usable as electric motors or generators which are compact in size and of high quality.

For example, an electric rotating machine mounted on a vehicle is required to generate more output power because of an increase of vehicle loads, although the space assigned to mount the electric rotating machine in an engine compartment is becoming smaller.

As described, for example, in Japanese Patent No. 3604326, there is known a compact and high-output electric rotating machine having a structure in which the resistance of phase windings thereof is small, the lamination factor of electric conductors accommodated in the magnetic circuit of a stator thereof is large, and the turn portions of the phase windings are in proper alignment and wound densily.

This patent document describes, as an assembling method of the stator, a step of preparing a stator winding of a predetermined shape by winding pillar-conductors in the circumferential direction a plurality of times so as to be laminated in the slot direction (in the radial direction), a step of disposing a plurality of divided cores in a ring around the outer periphery of the stator winding in a state of being overlapped at their lap portions, a step of moving the divided cores radially inwardly so that they are inserted into the stator winding, and a step of fixing the divided cores to one another.

However, the stator of an electric rotating machine of the type in which its stator core is constituted by a plurality of divided cores has a problem in that it is difficult for the electric rotating machine to output a sufficiently large power, because the divided portions (surfaces of the divided cores) have a magnetic resistance.

Although the above patent discloses reducing the magnetic resistance by the provision of the Lap portions, the effect is restrictive.

In addition, there is another problem that an eddy current occurs in each lap portion, causing iron loss (core loss) to increase.

The present invention provides a stator of an electric rotating machine comprising:

a stator core having slots formed at an inner periphery thereof along a circumferential direction thereof; and

a stator winding constituted by conductive wires wound on the slots

the stator winding including in-slot portions accommodated in the slots and turn portions each connecting each adjacent two of the in-slot portions outside of the slots,

the stator core including a core member having at least three first tooth portions extending in a radial direction of the stator core and a core back portion integrally connecting the first tooth portions at a radially end side thereof,

the core member being configured such that each of the first tooth portions folded toward the core back portion is capable of unfolding to extend between a corresponding adjacent two of the in-slot portions when the core member is at a predetermined axial position with respect to the stator winding.

According to the present invention, there is provided a compact and high-output electric rotating machine including a stator having less magnetic resistance in a stator core thereof.

Other advantages and features of the invention will become apparent from the following description including the drawings and claims.