Vehicle driving device

A vehicle driving device comprising:

• a rotary electric machine that is a driving force source of a first wheel and a second wheel;
• a speed reduction device that reduces a speed of a rotation of the rotary electric machine;
• and
• a differential gear device that distributes to the first wheel and the second wheel, a driving force that is transmitted from the rotary electric machine via the speed reduction device, wherein
• the speed reduction device and the differential gear device are disposed coaxially with the rotary electric machine,
• the speed reduction device has a first planetary gear mechanism and a second planetary gear mechanism, the first planetary gear mechanism is disposed on a rotary electric machine side relative to the second planetary gear mechanism in an order of a power transmission path, and the first planetary gear mechanism is disposed on the rotary electric machine side relative to the second planetary gear mechanism along an axial direction,
• a helix angle of a helical tooth of the first planetary gear mechanism and a helix angle of a helical tooth of the second planetary gear mechanism are formed so that a thrust force of the first planetary gear mechanism and a thrust force of the second planetary gear mechanism are in mutually opposite directions in the axial direction, and
• the helix angle of the helical tooth of the first planetary gear mechanism is larger than the helix angle of the helical tooth of the second planetary gear mechanism.