Straddle electric vehicle

1. A straddle electric vehicle which drives by use of driving power generated by an electric motor, comprising:

a battery case which accommodates a battery as an electric power supply for the electric motor, and is placed between a front wheel and a rear wheel;

a swing arm pivotably coupled at its front end portion to a vehicle body frame such that the swing arm supports the rear wheel by its rear end portion;

a transmission mechanism which changes a speed of the driving power generated by the electric motor;

an inverter connected to the battery and to the electric motor; and

an oil pan which reserves oil used for cooling and/or lubrication,

wherein the electric motor is placed rearward relative to the battery case and forward relative to the rear wheel,

wherein the battery case is mounted to a frame member extending below the battery case,

wherein the transmission mechanism is placed rearward relative to the battery case, the electric motor and the transmission mechanism are arranged substantially vertically, and the electric motor is placed above the transmission mechanism,

wherein the oil pan is placed below the transmission mechanism, and the inverter is placed above the electric motor, and

wherein the oil reserved in the oil pan is fed to the inverter, the electric motor and the transmission mechanism, and returned to the oil pan.

2. The straddle electric vehicle according to claim 1 ,

wherein a rotary shaft of the electric motor is placed above a pivot around which the swing arm is pivotable.

3. The straddle electric vehicle according to claim 2 ,

wherein a front end portion of the electric motor is placed forward relative to the pivot.

4. The straddle electric vehicle according to claim 1 ,

wherein a rotary shaft of the electric motor is placed rearward relative to an input shaft of the transmission mechanism.

5. The straddle electric vehicle according to claim 4 , comprising:

a motor accommodating section accommodating the electric motor; and

a transmission accommodating section accommodating the transmission mechanism;

wherein a front end portion of the motor accommodating section is placed rearward relative to a front end portion of the transmission accommodating section.

6. The straddle electric vehicle according to claim 5 ,

wherein the vehicle body frame includes a first frame which extends rearward and downward from a head pipe and is joined to a front portion of the transmission accommodating section; and

wherein the battery case is supported on the first frame in a state in which the battery case is mounted to the first frame.

7. The straddle electric vehicle according to claim 6 ,

wherein the vehicle body frame includes a second frame which is located above the first frame, extends rearward and downward from the head pipe, and is joined to a front portion of the motor accommodating section.

8. The straddle electric vehicle according to claim 7 ,

wherein the second frame is placed outward in a vehicle width direction relative to the battery case.

9. The straddle electric vehicle according to claim 5 ,

wherein the pivot is provided in the transmission accommodating section.

10. The straddle electric vehicle according to claim 5 ,

wherein an input shaft of the transmission mechanism is placed above the pivot; the straddle electric vehicle comprising:

a motor unit case including the motor accommodating section and the transmission accommodating section which are unitarily joined to each other;

wherein the motor unit case is configured as a portion of the vehicle body frame.

11. The straddle electric vehicle according to claim 1 ,

wherein an input shaft of the transmission mechanism is placed below the pivot.

12. The straddle electric vehicle according to claim 1 ,

wherein the vehicle body frame includes a down frame member extending downward from a head pipe and a lower frame member extending rearward from a lower end of the down frame member and below the battery case; and

wherein the battery case is placed rearward relative to the down frame member and mounted to the lower frame member.

13. The straddle electric vehicle according to claim 1 , further comprising:

an inverter connected to the battery and to the electric motor;

wherein the inverter is placed rearward relative to the battery case and above the electric motor.

14. A straddle electric vehicle which drives by use of driving power generated by an electric motor, comprising:

a battery case which accommodates a battery as an electric power supply for the electric motor, and is placed between a front and a rear wheel;

a swing arm pivotably coupled at its front end portion to a vehicle body frame such that the swing arm supports the rear wheel by its rear end portion;

a transmission mechanism which changes a speed of the driving power generated by the electric motor;

an inverter connected to the battery and to the electric motor; and

an oil pan which reserves oil used for cooling and/or lubrication,

wherein the electric motor is placed rearward relative to the battery case and forward relative to the rear wheel,

wherein the inverter is placed rearward relative to the battery case and above the electric motor,

wherein the transmission mechanism is placed rearward relative to the battery case, and the electric motor and the transmission mechanism are arranged substantially vertically such that the electric motor is placed above the transmission mechanism;

wherein the oil pan is placed below the transmission mechanism and the inverter is placed above the electric motor, and

wherein the oil reserved in the oil pan is fed to the inverter, the electric motor and the transmission mechanism, and returned to the oil pan.