Bus bar unit

1. A bus bar unit in which a plurality of bus bars are formed by insert molding and arranged in an axial direction of a stator, wherein each of the plurality of bus bars comprises:

a main body portion extending in a circumferential direction of the stator;

a through hole which is formed in the main body portion, and into which a support pin for supporting the main body portion of a predetermined bus bar, from among the plurality of bus bars, is inserted in the axial direction of the stator during said insert molding; and

an inner projecting portion and an outer projecting portion provided respectively on an inner side portion and an outer side portion of the main body portion in a radial direction of the stator so as to increase a sectional area of the main body portion in the circumferential direction of the stator,

wherein a total projecting amount of (i) a projecting amount in the radial direction of the inner projecting portion and (ii) a projecting amount in the radial direction of the outer projecting portion of the main body portion is larger than a hole length of the through hole in the radial direction of the stator.

2. The bus bar unit as defined in claim 1 ,

wherein the plurality of bus bars comprises four bus bars, and a plurality of through holes is provided in each of the four bus bars at intervals in the circumferential direction of the stator, and

wherein, in the axial direction of the stator, the plurality of through holes provided in three bus bars is arranged along an axis parallel to the axial direction of the stator.

3. The bus bar unit as defined in claim 1 ,

wherein a space between an extending portion extending outwardly in the radial direction of the stator from the main body portion and the outer projecting portion is filled with an insulating resin, and

wherein the extending portion has, at a distal end thereof, a coil connecting portion, and the coil connecting portion is connected to a winding terminal.

4. The bus bar unit as defined in claim 1 ,

wherein each bus bar among the plurality of bus bars comprises through holes in the main body portion, each of the through holes is at a corresponding location among a plurality of locations arranged at intervals along the circumferential direction of the stator, and

wherein, at each location among the plurality of locations,

through holes of at least two bus bars among the plurality of bus bars are aligned with each other along an axis parallel to the axial direction of the stator, wherein the aligned through holes are arranged for receiving a support pin during said insert molding, and

a further bus bar among the plurality of bus bars and different from said at least two bus bars does not have a through hole at said location, wherein said further bus bar is arranged to be supported by the support pin received in the aligned through holes during said insert molding.

5. The bus bar unit as defined in claim 4 , further comprising:

an insulating resin in which the plurality of bus bars is embedded by said insert molding,

wherein the insulating resin is absent inside the aligned through holes.

6. The bus bar unit as defined in claim 1 ,

wherein the plurality of bus bars comprises four bus bars,

wherein each bus bar among the four bus bars comprises through holes in the main body portion, each of the through holes is at a corresponding location among a plurality of locations arranged at intervals along the circumferential direction of the stator, and

wherein, at each location among the plurality of locations,

three through holes of three bus bars among the four bus bars are aligned with each other along an axis parallel to the axial direction of the stator, and

a fourth bus bar among the plurality of bus bars and different from said three bus bars does not have a through hole at said location.

7. The bus bar unit as defined in claim 6 , further comprising:

an insulating resin in which the four bus bars are embedded by said insert molding,

wherein the insulating resin is absent inside the aligned through holes.