Vehicle and control method thereof

1. A vehicle having an informing unit configured to inform vehicle information that relates a driving state, the vehicle comprising:

a fuel consumption priority mode selection switch to select a fuel consumption priority mode that gives priority to fuel consumption;

a driving state determination module configured to determine whether the driving state is an economy driving state based on a first determination criterion when the fuel consumption priority mode selection switch is turned off, the driving state determination module determining whether the driving state is the economy driving state based on a second determination criterion that is stricter for determining whether the driving state is the economy driving state in comparison with the first determination criterion, when the fuel consumption priority mode selection switch is turned on;

an informing control module configured to control the informing unit to inform a driver of a determination result of the driving state determination module.

2. A vehicle according to claim 1 , further comprising a driving force related physical quantity acquisition unit that acquires a physical quantity relating a driving force demand by the driver,

wherein the first and second determination criteria respectively regard that the driving state is the economy driving state when the acquired physical quantity is equal to or less than a predetermined threshold, and wherein the threshold in the second determination criterion is smaller than that in the first determination criterion.

3. A vehicle according to claim 1 , further comprising a vehicle speed related physical quantity acquisition unit that acquires a physical quantity relating a vehicle speed,

wherein the first and second determination criteria respectively regard that the driving state is the economy driving state when the acquired physical quantity is equal to or less than a predetermined vehicle speed related threshold, and wherein the vehicle speed related threshold in the second determination criterion is smaller than that in the first determination criterion.

4. A vehicle according to claim 1 , further comprising:

a motor capable of outputting power for driving; and

an accumulator capable of supplying and receiving electric power from the motor.

5. A vehicle according to claim 1 , further comprising:

an internal combustion engine capable of outputting power for driving; and

a power transmitting mechanism having an axle-side rotational element connected to a predetermined axle, and an engine-side rotational element connected to an engine shaft of the internal combustion engine and configured to differentially rotate with respect to the axle-side rotational element, the power transmitting mechanism capable of outputting at least a part of power from the engine shaft to the axle side.

6. A vehicle according to claim 5 , wherein the power transmitting mechanism is an electric power-mechanical power input output structure connected to the predetermined axle and the engine shaft of the internal combustion engine and outputting at least a part of power from the internal combustion engine to the axle side with input/output of electric power and mechanical power.

7. A vehicle according to claim 6 , wherein the electric power-mechanical power input output structure includes a power generation motor capable of inputting and outputting power, and a three shaft-type power input output assembly connected with three shafts, the predetermined axle, the engine shaft of the internal combustion engine, and a rotating shaft of the power generation motor, the three shaft-type power input output assembly configured to input and output power to one remaining shaft, based on input and output of powers from and to any two shafts selected among the three shafts.

8. A vehicle according to claim 5 , wherein the power transmitting mechanism is a continuously variable transmission.

9. A control method of a vehicle including an informing unit configured to inform vehicle information that relates a driving state, and a fuel consumption priority mode selection switch to select a fuel consumption priority mode that gives priority to fuel consumption, the method comprising the steps of:

(a) determining whether the driving state is an economy driving state based on a first determination criterion when the fuel consumption priority mode selection switch is turned off, the step (a) determining whether the driving state is the economy driving state based on a second determination criterion that is stricter for determining whether the driving state is the economy driving state in comparison with the first determination criterion, when the fuel consumption priority mode selection switch is turned on; and

(b) controlling the informing unit so that a driver is informed of a determination at the step (a).

10. A control method of a vehicle according to claim 9 , wherein the first and second determination criteria used at the step (a) respectively regard that the driving state is the economy driving state when a physical quantity relating a driving force demand by the driver is equal to or less than a predetermined threshold, and wherein the threshold in the second determination criterion is smaller than that in the first determination criterion.

11. A control method of a vehicle according to claim 9 , wherein the first and second determination criteria used at the step (a) respectively regard that the driving state is the economy driving state when a physical quantity relating a vehicle speed is equal to or less than a predetermined vehicle speed related threshold, and wherein the vehicle speed related threshold in the second determination criterion is smaller than that in the first determination criterion.