Rotary electric machine

1. A rotary electric machine comprising:

a stator core which includes core back portions having an arc shape, and teeth which protrude from inner circumference wall surfaces of the core back portions to an inner direction in a diameter direction of the core back portions;

a stator which includes bobbins having an electric insulation capability, which are arranged at both end surfaces in a shaft direction of the stator core, and coils which are wound around the teeth via the bobbins; and

a rotor which is coaxially arranged at an inner circumference of the stator;

wherein the bobbins include coil winding portions, which are arranged at end surfaces in a shaft direction of the teeth, on which the coils are wound; flange portions, which are arranged at end surfaces in a shaft direction of the core back portions, at which a plurality of bus ring maintaining portions are separately formed in a diameter direction of the core back portions, each of the plurality of bus ring maintaining portions extending in the shaft direction and a circumference direction of the core back portions; and wall portions which are arranged in an inner direction in a diameter direction of the core back portions at the bus ring maintaining portions,

wherein a plurality of bus rings, which are concentrically arranged at the bus ring maintaining portions, include coil connecting portions which protrude in an outer direction in a shaft direction of the stator core with respect to the bus ring maintaining portions,

wherein terminals of the coils are bent in an outer direction in a diameter direction of the stator core at positions of end surfaces of the wall portions, and are connected to the coil connecting portions of the bus rings,

wherein the end surfaces of the wall portions protrude in an outer direction in a shaft direction of the stator core with respect to end surfaces of the bus rings, and are positioned in an inner direction in a shaft direction of the stator core with respect to end surfaces of the coil connecting portions, and

wherein the terminals of the coils are separated from the end surfaces of the wall portions.

2. A rotary electric machine as recited in claim 1 , wherein the wall portions comprise protruding portions, about which the terminals of the coils are bent.

3. A rotary electric machine comprising:

a stator core which includes core back portions having an arc shape, and teeth which protrude from inner circumference wall surfaces of the core back portions to an inner direction in a diameter direction of the core back portions;

a stator which includes bobbins having an electric insulation capability, which are arranged at both end surfaces in a shaft direction of the stator core, and coils which are wound around the teeth via the bobbins; and

a rotor which is coaxially arranged at an inner circumference of the stator;

wherein the bobbins include coil winding portions, which are arranged at end surfaces in a shaft direction of the teeth, on which the coils are wound; flange portions, which are arranged at end surfaces in a shaft direction of the core back portions, at which a plurality of bus ring maintaining portions are separately formed in a diameter direction of the core back portions, each of the plurality of bus ring maintaining portions extending in the shaft direction and a circumference direction of the core back portions; and wall portions which are arranged in an inner direction in a diameter direction of the core back portions at the bus ring maintaining portions,

wherein a plurality of bus rings, which are concentrically arranged at the bus ring maintaining portions, include coil connecting portions which protrude in an outer direction in a shaft direction of the stator core with respect to the bus ring maintaining portions,

wherein terminals of the coils are bent in an outer direction in a diameter direction of the stator core at positions of end surfaces of the wall portions, and are connected to the coil connecting portions of the bus rings,

wherein the end surfaces of the wall portions protrude in an outer direction in a shaft direction of the stator core with respect to end surfaces of the bus rings, and are positioned in an inner direction in a shaft direction of the stator core with respect to end surfaces of the coil connecting portions, and

wherein boundaries of film exfoliations of the terminals of the coils are positioned in an outer direction in a shaft direction of the stator core with respect to the end surfaces of the wall portions of the bobbins.

4. A rotary electric machine as recited in claim 3 , wherein a bend radius of the terminals of the coils is Rc, and an air distance, by which an insulation capability between the terminals of the coils and the other bus rings which are different from the bus ring to which the terminals of the coils are connected, is maintained, is Dv, and a distance Ds in a shaft direction between the end surfaces of the wall portions of the bobbins and the end surfaces of the bus rings is set as the following formula:

Ds≥Dv−Rc.

5. A rotary electric machine as recited in claim 4 , wherein the wall portions comprise protruding portions, about which the terminals of the coils are bent.

6. A rotary electric machine as recited in claim 3 , wherein the wall portions comprise protruding portions, about which the terminals of the coils are bent.

7. A rotary electric machine comprising:

a stator core which includes core back portions having an arc shape, and teeth which protrude from inner circumference wall surfaces of the core back portions to an inner direction in a diameter direction of the core back portions;

a stator which includes bobbins having an electric insulation capability, which are arranged at both end surfaces in a shaft direction of the stator core, and coils which are wound around the teeth via the bobbins; and

a rotor which is coaxially arranged at an inner circumference of the stator;

wherein the bobbins include coil winding portions, which are arranged at end surfaces in a shaft direction of the teeth, on which the coils are wound; flange portions, which are arranged at end surfaces in a shaft direction of the core back portions, at which a plurality of bus ring maintaining portions are separately formed in a diameter direction of the core back portions, each of the plurality of bus ring maintaining portions extending in the shaft direction and a circumference direction of the core back portions; and wall portions which are arranged in an inner direction in a diameter direction of the core back portions at the bus ring maintaining portions,

wherein a plurality of bus rings, which are concentrically arranged at the bus ring maintaining portions, include coil connecting portions which protrude in an outer direction in a shaft direction of the stator core with respect to the bus ring maintaining portions,

wherein terminals of the coils are bent in an outer direction in a diameter direction of the stator core at positions of end surfaces of the wall portions, and are connected to the coil connecting portions of the bus rings,

wherein the end surfaces of the wall portions protrude in an outer direction in a shaft direction of the stator core with respect to end surfaces of the bus rings, and are positioned in an inner direction in a shaft direction of the stator core with respect to end surfaces of the coil connecting portions, and

wherein a bend radius of the terminals of the coils is Rc, and an air distance, by which an insulation capability between the terminals of the coils and the other bus rings which are different from the bus ring to which the terminals of the coils are connected, is maintained, is Dv, and a distance Ds in a shaft direction between the end surfaces of the wall portions of the bobbins and the end surfaces of the bus rings is set as the following formula:

Ds≥Dv−Rc.

8. A rotary electric machine as recited in claim 7 , wherein the wall portions comprise protruding portions, about which the terminals of the coils are bent.