Patent Description:
In recent years, for purposes of reducing an environmental load and the like, hybrid vehicles including a motor in addition to an engine as drive sources of vehicle travel have been widespread.

In Patent document <NUM>, an automobile that includes an engine and a motor as drive sources for travel is disclosed. In the automobile disclosed in Patent document <NUM>, both of the engine and the motor, which are provided as the drive sources for the travel, are mounted in a front area.

The automobile disclosed in Patent document <NUM> can be switched between an engine-drive mode in which the automobile travels by using the engine and a motor-drive mode in which the automobile travels by using the motor. When a driver selects the motor-drive mode, the automobile travels by driving the motor.

Meanwhile, when the driver selects the engine-drive mode, the motor exerts a torque assist function at a start of the automobile, and the automobile travels at a specified vehicle speed or higher by driving the engine.

[Patent document <NUM>] <CIT>
<CIT> describes that a vehicle includes a motor, a high-voltage device, and a power converter. The motor moves the vehicle. The high-voltage device is disposed inside a vehicle cabin of the vehicle. The power converter is disposed outside the vehicle cabin. The power converter is connected to the motor and the high-voltage device to convert electric power output from the high-voltage device and to supply the converted electric power to the motor. The high-voltage device is arranged to be juxtaposed to the power converter along a front-rear direction of the vehicle.

By the way, further improvement in vehicle motion performance has been requested for the hybrid vehicle as described above. When it is attempted to improve the vehicle motion performance, it is beneficial to unitize and arrange the engine and the motor in an area near a center of the vehicle. When the engine and the motor are unitized and arranged in the area as described above, the vehicle can easily turn, and the vehicle motion performance can be improved.

Here, in the hybrid vehicle, a battery is a source of electricity for the motor. While the battery outputs a direct current (DC or DC current), a majority of the motors, each of which is used as a drive source for the travel of the vehicle, is driven by an alternating current (AC or AC current). For this reason, an inverter is interposed between the battery and the motor, and the inverter converts the DC current into the AC current.

For the conventional hybrid vehicles, a structure of fixing the inverter onto the motor is frequently adopted. This structure is adopted to reduce a distance between the motor and the inverter and to reduce a length of a bus bar as a connection wire between the motor and the inverter as much as possible.

However, in the vehicle, for which a drive unit unitizing the engine and the motor is adopted, direct fixation of the inverter onto the drive unit such as the motor is desirably avoided as much as possible. This is because, if the inverter is fixed onto the motor in the vehicle, for which the drive unit having the engine and the motor is adopted, the vibration generated during driving of the engine is directly transmitted to the inverter. It is considered that electrical components of the inverter are damaged by this vibration and, depending on a case, the vibration becomes a cause of failure.

Although it is considered that the failure of the inverter can be avoided by constructing the inverter of vibration-resistant parts even when a structure of fixing the inverter onto the motor is adopted. However, the adoption of such a structure causes an increase in manufacturing cost of the inverter and thus is difficult.

The present invention has been made to solve the problem as described above and therefore has a purpose of providing a vehicle capable of suppressing failure of an inverter while suppressing an increase in manufacturing cost by unitizing an engine and a motor.

The above problem is solved by the invention as defined in the independent claim.

The present inventors considered a structure of separately arranging the inverter from the drive unit. When the inverter is separately arranged from the drive unit, just as described, the vibration generated during driving of the engine is not directly transmitted to the inverter. Thus, failure of the inverter can be suppressed by adopting the inverter using high-price electrical components. Therefore, it is considered that the failure of the inverter can be suppressed by suppressing the increase in the manufacturing cost.

However, in the case where the inverter is separated from the drive unit, a distance between the inverter and the motor is increased, and thus a wire length of the connection wire that connects the inverter and the motor has to be increased by such an increase. As described above, in the related art for which a structure of connecting the inverter and the motor by a bus bar is adopted, in the case where the wire length is increased as described above, stress that acts on the bus bar during the vibration of the engine is increased. In the case where it is attempted to prevent the damage to the connection wire at the time when such an inverter is separately arranged from the drive unit, it is considered to make the bus bar strong by increasing a cross-sectional area, using a high-strength material, or the like. However, such a case causes the increase in the manufacturing cost and weight increase.

In view of the above, a vehicle according to an aspect of the present invention includes: a drive unit that has an engine and a motor, particularly arranged adjacent to each other, and is a drive source for travel of the vehicle; an inverter that converts a direct current (DC or DC current) into an alternating current (AC or AC current) and outputs the AC current; and a connection wire that electrically connects an output terminal of the inverter and an input terminal of the motor. The inverter is arranged separately from the drive unit. The connection wire has flexibility and/or is formed of a wire harness, a wire length of which is longer than a linear distance between the output terminal of the inverter and the input terminal of the motor.

In the vehicle according to the above aspect, the drive unit, in which the engine and the motor are unitized, is provided. Thus, compared to a case where the engine and the motor are not unitized, it is possible to downsize the drive source and to arrange the drive unit at or near a center of the vehicle. Therefore, it is possible to improve vehicle motion performance of the vehicle according to the above aspect.

In the vehicle according to the above aspect, the inverter is arranged separately from the drive unit. Thus, it is possible to suppress vibration generated during driving of the engine from having an impact on the inverter. Thus, in the vehicle according to the above aspect, it is possible to suppress failure of the inverter caused by the vibration during driving of the engine.

Furthermore, in the vehicle according to the above aspect, the wire harness having the flexibility is used instead of a bus bar to connect the inverter and the motor, and the wire length of the wire harness is set to be longer than the linear distance between the output terminal of the inverter and the input terminal of the motor. Thus, it is possible to suppress large stress from acting on the wire harness even when the vibration is generated during driving of the engine. That is, the wire harness having the flexibility is used, and the wire harness having the longer wire length than the linear distance is flexed and arranged between the inverter and the motor. In this way, even when the vibration is applied to the wire harness, buffering can be achieved. Therefore, it is possible to suppress the damage to the wire harness caused by the vibration while suppressing the increase in the cost.

In the vehicle according to the above aspect, the drive unit may be attached to a first position of a vehicle body, and the inverter may be attached to a second position that is separated from the first position in the vehicle body.

As described above, it is possible to suppress transmission of the vibration from the engine to the inverter via an attachment position of the vehicle body by separating the attachment position (the second position) of the inverter to the vehicle body from the attachment position (the first position) of the drive unit to the vehicle body. Thus, the adoption of the above configuration is further beneficial to suppression of the damage to the inverter caused by the vibration during driving of the engine.

In the vehicle according to the above aspect, the second position may be a portion formed with a floor tunnel in a floor panel, and the connection wire may be arranged in the floor tunnel.

As described above, when the inverter is attached to the portion formed with the floor tunnel in the floor panel, it is possible to effectively suppress the transmission of the vibration during driving of the engine to the inverter via the vehicle body. That is, the floor tunnel is a high-rigid portion that is provided to reinforce rigidity of the vehicle body. Thus, the attachment of the inverter to such a portion is beneficial to suppression of the transmission of the vibration caused by driving of the engine to the inverter.

As described above, when the connection wire is arranged in the floor tunnel, it is possible to suppress exposure of the connection wire to a cabin and narrowing of the cabin.

In the vehicle according to the above aspect, when the engine and the connection wire are seen from one side in a direction in which the engine and the motor are adjacent to each other, the connection wire may be arranged to be located on an inner side of an outer circumference of the engine.

As described above, since the connection wire is arranged to be located on the inner side of the outer circumference of the engine, it is possible to fit the connection wire within the floor tunnel while suppressing an increase in cross-sectional size of the floor tunnel.

The inverter is arranged separately from the cover member. In this way, it is possible to further suppress the vibration generated during driving of the engine from being transmitted to the inverter via the cover member. That is, the vibration of the engine is transmitted to the cover member that is provided to cover the periphery of the shaft. However, when the inverter is arranged separately from the cover member, it is possible to suppress the vibration generated during driving of the engine from being transmitted to the inverter via the cover member.

In the vehicle according to the above aspect, when the cover member and the connection wire are seen from an outer side in a direction that crosses an extending direction of the shaft, the connection wire may be arranged to be curved in a manner to run around a specified area above the cover member.

As described above, in the case where a configuration that the connection wire is arranged to be curved in the manner to run around the specified area above the cover member is adopted, it is possible to attach another member to the specified area and to efficiently use the space. Thus, it is beneficial to downsizing of the set configuration including the drive unit and auxiliary parts.

In the vehicle according to the above aspect, a motor cooling member as a member for cooling the motor may be attached to the specified area.

When the motor cooling member is attached to the specified area as described above, it is possible to efficiently use the space.

The vehicle according to the above aspect may further include: a motor cooling oil path as a path of oil for cooling the motor; and an ebullient cooler. The ebullient cooler particularly has: a circulation path for circulating an ebullient cooling refrigerant, a boiling point of which is lower than that of the oil flowing through the motor cooling oil path; an ebullient section that is disposed in the middle of the circulation path and in which the oil and the ebullient cooling refrigerant exchange heat; and a condensation section that condenses the ebullient cooling refrigerant. The motor cooling member may be the condensation section of the ebullient cooler.

As described above, when the ebullient cooler is attached to the motor, it is possible to effectively cool the heat generated during driving of the motor. Thus, in the case where the above configuration is adopted, the motor can be maintained at the appropriate temperature even when the motor is driven to generate high output or is continuously driven for a long time.

In the vehicle according to the above aspect, the condensation section may be attached to an upper side of the cover member in a vertical direction of the vehicle.

As described above, when such a configuration that the condensation section of the ebullient cooler is attached to the upper side of the cover member is adopted, it is possible to suppress the heat released from the condensation section from being transferred to the motor and the like via the cover member. That is, it is considered that the heat released from the condensation section is transferred to the cover member in the case where the condensation section is attached to a lower side of the cover member. In such a case, the heat released from the condensation section is transferred to the motor via the cover member.

Meanwhile, when the condensation section is attached to the upper side of the cover member as described above, it is possible to suppress the heat released from the condensation section from being transferred to the motor via the cover member.

In the vehicle according to the above aspect, a plurality of the connection wires may be provided, one end of each of the connection wires may be connected to respective one of a plurality of first connection portions in the output terminal, and the other end of each of the connection wires may be connected to respective one of a plurality of second connection portions in the input terminal. In the case where a first imaginary straight line running through the plurality of the first connection portions and a second imaginary straight line running through the plurality of the second connection portions are assumed, and the output terminal and the input terminal are seen from the outer side in the direction that crosses the extending direction of the shaft, at least one of the first imaginary straight line and the second imaginary straight line may extend in an oblique direction with respect to the extending direction of the shaft.

As described above, when the plurality of the first connection portions and/or the plurality of the second connection portions is arranged such that at least one of the first imaginary straight line and the second imaginary straight line extends in the oblique direction with respect to the extending direction of the shaft, it is possible to suppress the connection wires from overlapping each other in a cross-sectional direction of the cover member. Thus, it is possible to arrange the connection wires along a surface of the cover member and thus to suppress projection of the cover member in the cross-sectional direction.

In the vehicle according to the above aspect, the engine may be a rotary engine.

As described above, in the case where the rotary engine is adopted, the vibration is generated at a high speed. However, when the connection wires as described above are adopted, it is possible to suppress the damage to the inverter and the connection wires caused by the vibration during driving of the engine.

Particularly, the motor provided in the drive unit is arranged adjacent to a rear side of the engine.

Further particularly, the engine and the motor have a direct-coupling structure.

Further particularly, the engine and the motor are configured to share an output shaft.

In the vehicle according to each of the above aspects, it is possible to suppress the failure of the inverter while suppressing the increase in the manufacturing cost by unitizing the engine and the motor.

A description will hereinafter be made on an embodiment of the present invention with reference to the drawings. All of the features as shown in the drawings may not necessarily be essential. The embodiment, which will be described below, merely constitutes an example of the present invention, and the present invention is not limited to the following embodiment in any respect except for an essential configuration thereof.

In the drawings used in the following description, "F", "R", "U", "L", "Le", and "Ri" respectively indicate a front side of a vehicle, a rear side of the vehicle, an upper side of the vehicle, a lower side of the vehicle, a left side of the vehicle, and a right side of the vehicle.

A description will be made on a schematic configuration of a vehicle <NUM> according to this embodiment with reference to <FIG>.

As illustrated in <FIG>, in the vehicle <NUM>, a drive unit <NUM> for driving the vehicle <NUM> is particularly mounted in a rear portion of a front area 1a. The drive unit <NUM> includes one or more engines <NUM> to <NUM> and a motor <NUM>. A detailed structure of the drive unit <NUM> will be described below.

A propeller shaft <NUM> is particularly connected to an output shaft of the drive unit <NUM>. The propeller shaft <NUM> is a "shaft" that transmits drive power from the drive unit <NUM> to rear wheels <NUM>, <NUM> as drive wheels. The propeller shaft <NUM> particularly extends rearward at a center in a vehicle width direction of the vehicle <NUM>. A rear end of the propeller shaft <NUM> is particularly connected to a transmission <NUM>.

A differential gear <NUM> is particularly connected to the transmission <NUM>. Driveshafts <NUM>, <NUM> are respectively coupled to left and right portions of the differential gear <NUM> in the vehicle width direction. The driveshafts <NUM>, <NUM> are connected to the rear wheels <NUM>, <NUM>, respectively. That is, in the vehicle <NUM> according to this embodiment, the rear wheels <NUM>, <NUM> are particularly driven for travel by the drive power that is generated by the drive unit <NUM> mounted in the front area 1a.

Particularly, in the vehicle <NUM>, motors <NUM>, <NUM> are respectively connected to front wheels <NUM>, <NUM>. Although not illustrated in detail, each of the motors <NUM>, <NUM> is particularly a so-called in-wheel motor. Each of the motors <NUM>, <NUM> particularly functions as an assist motor that generates power at a start of the vehicle <NUM> and particularly transmits the power to respective one of the front wheels <NUM>, <NUM>. Each of the motors <NUM>, <NUM> also functions as a regenerative brake that generates electricity during deceleration of the vehicle <NUM>. The electricity, which is generated by the motors <NUM>, <NUM> during the deceleration of the vehicle <NUM>, is particularly stored in a capacitor <NUM> and the like.

A battery <NUM> and an inverter <NUM> are also mounted on the vehicle <NUM>. The battery <NUM> is an electricity storage module for supplying the electricity to the motor <NUM> in the drive unit <NUM>. The inverter <NUM> is an electricity conversion module that converts a direct current (DC or DC current) supplied from the battery <NUM> to an alternating current (AC or AC current).

Here, the vehicle <NUM> according to this embodiment particularly has, as drive modes of the drive unit <NUM>, an engine-drive mode and a motor-drive mode. The engine-drive mode is a mode in which the rear wheels <NUM>, <NUM> are driven by the drive power output from the engines <NUM> to <NUM> and the vehicle <NUM> thereby travels. The motor-drive mode is a mode in which the rear wheels <NUM>, <NUM> are driven by the drive power output from the motor <NUM> and the vehicle <NUM> thereby travels.

The vehicle <NUM> is particularly configured that the motor <NUM> does not generate the drive power at the time of driving in the engine-drive mode and that the engines <NUM> to <NUM> do not generate the drive power at the time of driving in the motor-drive mode.

In the vehicle <NUM>, a drive mode control section <NUM> particularly executes switching control between the engine-drive mode and the motor-drive mode. The drive mode control section <NUM> is particularly configured to include a microprocessor that has a CPU, ROM, RAM, and the like. The drive mode control section <NUM> particularly executes drive mode control on the basis of an instruction from a driver, a situation of the vehicle <NUM> (a vehicle speed, acceleration/deceleration, a battery remaining amount), or the like.

A description will be made on a mounting position of the drive unit <NUM> in the vehicle <NUM> with reference to <FIG>.

As described above, in the vehicle <NUM>, the drive unit <NUM> is particularly mounted in the rear portion of the front area 1a. More specifically, the drive unit <NUM> is particularly mounted such that center of gravity Ax10 of the drive unit <NUM> is located behind rotation center Ax23 of the front wheels <NUM>, <NUM> (only the front wheel <NUM> is illustrated in <FIG>). In addition, the drive unit <NUM> is particularly mounted such that the center of gravity Ax10 thereof is located below the rotation center Ax23 of the front wheels <NUM>, <NUM>.

That is, in the vehicle <NUM>, the drive unit <NUM> as a heavy object is made to be compact, and the drive unit <NUM> is thereby mounted in the rear portion of the front area 1a and below a hood <NUM> with a clearance being interposed therebetween. In this way, a position Ax1 of center of gravity of the vehicle <NUM> can be set to a low position substantially at the center in a longitudinal direction of the vehicle <NUM>.

A description will be made on a detailed configuration of the drive unit <NUM> and configurations of peripheries thereof with reference to <FIG>.

Particularly, as illustrated in <FIG> and <FIG>, each of the engines <NUM> to <NUM> provided in the drive unit <NUM> is a rotary engine having a rotary piston as an example. The adoption of the rotary engines as the engines <NUM> to <NUM> in the vehicle <NUM> is beneficial for downsizing of the drive unit <NUM>. Although not illustrated in detail, the drive unit <NUM> is particularly fixed to a front subframe via a mount. The front subframe corresponds to a "first position of a vehicle body" and is a part of the vehicle body that is provided, in a lower portion of the front area 1a, across front side frames disposed on the right and left sides.

As illustrated in <FIG>, an oil pan <NUM> is disposed below the engines <NUM> to <NUM>. The oil pan <NUM> particularly has a flat shape in which a dimension in a height direction is smaller than dimensions in the vehicle longitudinal direction and the vehicle width direction. This is beneficial to suppress a height of the drive unit <NUM> to be low.

As described above, in the vehicle <NUM> according to this embodiment, the oil pan <NUM> particularly has the flat shape, and thus an accommodation volume of engine oil therein is low. For this reason, the oil pan <NUM> has a primary purpose of collecting the engine oil that has flowed through the engines <NUM> to <NUM>. Thus, an oil tank <NUM> is particularly provided on a side of the drive unit <NUM> to store the engine oil collected in the oil pan <NUM>.

As illustrated in <FIG> and <FIG>, a radiator <NUM> and an oil cooler <NUM> are particularly disposed in front of the drive unit <NUM>. The radiator <NUM> is a device for cooling a coolant, a temperature of which has become high by heat from the engines <NUM> to <NUM>, and has a radiator fan 31a on a rear side thereof.

The oil cooler <NUM> is particularly arranged behind the radiator <NUM> and is disposed along the radiator <NUM>. The oil cooler <NUM> particularly has smaller plane size than the radiator <NUM>.

Pipes <NUM>, <NUM> particularly connect the engines <NUM> to <NUM> and the radiator <NUM>. A water pump <NUM> is provided to a connection portion between the pipe <NUM> and each of the engines <NUM> to <NUM>.

Two each of the oil cooler <NUM>, the engines <NUM> to <NUM>, the oil tank <NUM>, and the oil pan <NUM> are particularly connected by respective one of pipes <NUM> to <NUM> and the like. An oil pump <NUM> is provided to a connection portion between the pipe <NUM> and each of the engines <NUM> to <NUM>.

The motor <NUM> in the drive unit <NUM> is particularly arranged behind or adjacent to a rear side of the engine <NUM>. The engines <NUM> to <NUM> and the motor <NUM> particularly have a direct-coupling structure to share an output shaft. In a vertical direction and the vehicle width direction of the vehicle <NUM>, the motor <NUM> is particularly formed to have smaller external size than each of the engines <NUM> to <NUM>.

As illustrated in <FIG>, two heat exchangers <NUM>, <NUM> are particularly attached to a side housing 14b of the motor <NUM>. Both of the heat exchangers <NUM>, <NUM> are particularly arranged on the left side in the vehicle width direction. In addition, the heat exchanger <NUM> is particularly attached to the side housing 14b of the motor <NUM> in a state of being separated upward from the heat exchanger <NUM>. In addition, the heat exchangers <NUM>, <NUM> are particularly arranged to be located in front of a rear housing 14a of the motor <NUM>. In other words, the heat exchanger <NUM> and the heat exchanger <NUM> are particularly arranged to be located on the side housing 14b of the motor <NUM> in the longitudinal direction of the vehicle <NUM>.

In addition, each of the heat exchanger <NUM> and the heat exchanger <NUM> particularly has a flat external shape in which a dimension in a height direction is smaller than a dimension in a longitudinal dimension and a dimension in a width direction. The adoption of the heat exchanger <NUM> and the heat exchanger <NUM>, each of which has such an external shape, is beneficial to downsize a set configuration in which the heat exchangers <NUM>, <NUM> are attached to the drive unit <NUM>.

As illustrated in <FIG>, an end surface on a rear end side of the rear housing 14a of the motor <NUM> is particularly covered with a torque tube <NUM>. The torque tube <NUM> corresponds to a "cover member". An ebullient cooler <NUM> is particularly provided in an area from the side housing 14b of the motor <NUM> to a front portion of the torque tube <NUM>. The ebullient cooler <NUM> particularly has an ebullient section 44a, a condensation section 44b, pipes 44c, and an ebullient cooler fan 44d. Each of the pipes 44c in the ebullient cooler <NUM> is filled with an ebullient cooling refrigerant, a boiling point of which is lower than that of oil for cooling the motor <NUM>.

The ebullient section 44a is particularly a section that is attached to the side housing 14b of the motor <NUM> for heat exchange between the ebullient cooling refrigerant and the oil for cooling the motor <NUM> (motor cooling oil).

The condensation section 44b is particularly attached to the front portion of the torque tube <NUM>, which is arranged behind the motor <NUM>. The condensation section 44b is particularly a section that condenses the ebullient cooling refrigerant boiled (evaporated) by the heat exchange in the ebullient section 44a. Each of the pipes 44c is a circulation path for the ebullient cooling refrigerant between the ebullient section 44a and the condensation section 44b. The ebullient cooler fan 44d is a section that promotes the condensation of the ebullient cooling refrigerant by blowing air to the condensation section 44b.

In the ebullient cooler <NUM>, the ebullient cooler fan 44d is particularly arranged adjacent to a lower portion of the condensation section 44b. The ebullient cooler fan 44d particularly blows the air upward. Since the condensation section 44b and the ebullient cooler fan 44d in the ebullient cooler <NUM> are attached to the torque tube <NUM> behind the motor <NUM>, it is possible to prevent the air that has flowed through the condensation section 44b and has been warmed from being blown again to the housings 14a, 14b of the motor <NUM>. Thus, this is effective to maintain the motor <NUM> at an appropriate temperature.

Although not illustrated in detail, a paths, through each of which the motor cooling oil for cooling the motor <NUM> flows, and an oil control valve for switching the paths are particularly provided in the housings 14a, 14b of the motor <NUM>.

A description will be made on a cooling configuration of the motor <NUM> in the drive unit <NUM> with reference to <FIG>.

As illustrated in <FIG>, the motor <NUM> particularly has the housings 14a, 14b (only the side housing 14b is illustrated in <FIG>), a rotor-stator 14c, and an oil pan 14d. Motor cooling oil paths LN22, LN31, LN32 are particularly connected to upper portions of the housings 14a, 14b.

In the motor-drive mode, the motor cooling oil particularly flows through any of the motor cooling oil paths LN22, LN31, LN32 to cool the rotor-stator 14c and then flows into the oil pan 14d. The motor cooling oil that has been received by the oil pan 14d is particularly delivered to an oil pump <NUM> for the motor <NUM> through a motor cooling oil path LN33. A pressure-relief valve <NUM> is also connected to the motor cooling oil path LN33.

The motor cooling oil is particularly delivered from the oil pump <NUM> to the oil control valve <NUM> through a motor cooling oil path LN34. The oil control valve <NUM> is a valve that switches the motor cooling oil delivery path to one of a motor cooling oil path LN21 and the motor cooling oil path LN22.

The motor cooling oil path LN21 is connected to the oil control valve <NUM>. The oil control valve <NUM> is a valve that switches the motor cooling oil delivery path to one of a motor cooling oil path LN11 and a motor cooling oil path LN12.

The motor cooling oil path LN11 is particularly connected to the motor cooling oil path LN31 via the heat exchanger <NUM>. The motor cooling oil path LN12 is particularly connected to the motor cooling oil path LN32 via the heat exchanger <NUM>.

In an engine oil circulation path, the engine oil that is pumped out of the oil pump <NUM> flows from an engine cooling oil path LN41 to an engine cooling oil path LN42 via the heat exchanger <NUM>. The engine oil that has flowed into the engine cooling oil path LN42 through the heat exchanger <NUM> is delivered to an eccentric shaft. Then, the engine oil lubricates and cools a rotor.

In addition, some of the engine oil that has flowed into the engine cooling oil path LN42 is particularly injected into a combustion chamber of each of the engines <NUM> to <NUM> to lubricate and cool a housing, an apex seal, and a side seal.

In the heat exchanger <NUM>, the motor cooling oil and the engine oil can exchange the heat. That is, in the motor-drive mode, the heat generated in the motor <NUM> can be transferred to the engine oil so as to cool the motor <NUM> and can thereby increase a temperature of the engine oil. Thus, in the vehicle <NUM>, in the motor-drive mode, the engine oil circulation path can be shared to cool the motor <NUM>, and each of the engines <NUM> to <NUM> in a state where fuel is not supplied to the combustion chamber can be warmed. As a result, it is possible to downsize the cooling system for the drive unit <NUM> and to improve engine efficiency at the time when the drive mode is shifted to the engine-drive mode.

In the coolant circulation path for the engines <NUM> to <NUM>, the coolant that has flowed out of a high-pressure water jacket for the engines <NUM> to <NUM> flows from an engine coolant path LN43 to an engine coolant path LN44 via the heat exchanger <NUM>. The coolant that has flowed into the engine coolant path LN44 through the heat exchanger <NUM> flows into a low-pressure water jacket for the engines <NUM> to <NUM>.

In the heat exchanger <NUM>, the motor cooling oil and the engine cooling coolant can exchange the heat. Also, in this way, in the motor-drive mode, the heat generated in the motor <NUM> can be transferred to the coolant so as to cool the motor <NUM> and can thereby increase a temperature of the coolant. Thus, it is possible to downsize the cooling system for the drive unit <NUM> and to improve the engine efficiency at the time when the drive mode is shifted to the engine-drive mode. In the case where the cooling system for transferring the heat of the motor cooling oil to the coolant is used for the heat exchanger <NUM>, higher cooling performance can be achieved than a case where a cooling system for transferring the heat of the motor cooling oil to the engine oil is used for the heat exchanger <NUM>. This is because the radiator <NUM> for cooling the coolant is larger than the oil cooler <NUM> and also because the radiator <NUM> has the radiator fan 31a.

The ebullient section 44a of the ebullient cooler <NUM> is particularly disposed in the oil pan 14d of the motor <NUM>. Here, as it has been described with reference to <FIG>, an outer coat of the ebullient section 44a is attached to the side housing 14b of the motor <NUM>, and the ebullient cooling refrigerant, with which the pipes 44c are filled, can exchange the heat with the motor cooling oil in the oil pan 14d.

Particularly, the vehicle <NUM> also includes a valve control section <NUM> and an engine coolant temperature sensor <NUM>. The engine coolant temperature sensor <NUM> is, for example, provided to a pipe <NUM> between the engine <NUM> and the radiator <NUM>. The valve control section <NUM> is configured to include a microprocessor that has a CPU, ROM, RAM, and the like. The valve control section <NUM> is connected to the engine coolant temperature sensor <NUM> by a signal line SL1, is connected to the oil control valves <NUM>, <NUM> by signal lines SL2, SL3, respectively, and is connected to the ebullient cooler fan 44d of the ebullient cooler <NUM> by a signal line SL4.

In the motor-drive mode (in the case where the vehicle <NUM> travels by the drive power of the motor <NUM>), the valve control section <NUM> particularly executes switching control of the oil control valves <NUM>, <NUM> and drive control of the ebullient cooler fan 44d on the basis of information on an engine coolant temperature from the engine coolant temperature sensor <NUM>. More specifically, the valve control section <NUM> particularly executes the control as follows.

In the case where the engine coolant temperature is lower than a first threshold, the valve control section <NUM> particularly executes the switching control of the oil control valve <NUM> so as to connect the motor cooling oil path LN34 and the motor cooling oil path LN21, and particularly executes the switching control of the oil control valve <NUM> so as to connect the motor cooling oil path LN21 and the motor cooling oil path LN11. The ebullient cooler fan 44d is in a stopped state.

In the case where the engine coolant temperature is equal to or higher than the first threshold and is lower than a second threshold, the valve control section <NUM> particularly executes the switching control of the oil control valve <NUM> so as to connect the motor cooling oil path LN34 and the motor cooling oil path LN21, and particularly executes the switching control of the oil control valve <NUM> so as to connect the motor cooling oil path LN21 and the motor cooling oil path LN12. Then, the valve control section <NUM> particularly drives the ebullient cooler fan 44d.

In the case where the engine coolant temperature is equal to or higher than the second threshold, the valve control section <NUM> particularly executes the switching control of the oil control valve <NUM> so as to connect the motor cooling oil path LN34 and the motor cooling oil path LN21. Then, the valve control section <NUM> particularly maintains a driven state of the ebullient cooler fan 44d.

A description will be made on an arrangement mode of the inverter <NUM> in the vehicle <NUM> with reference to <FIG>.

As illustrated in <FIG>, the torque tube <NUM>, which is provided behind the motor <NUM> in the drive unit <NUM>, is particularly accommodated in an internal space (a lower space) 48a of a floor tunnel <NUM> in a floor panel (the vehicle body). The floor tunnel <NUM> is a portion that is provided behind a dash panel (not illustrated) for dividing the front area 1a and a cabin, and is provided as a portion that reinforces the floor panel.

Each of the components including the condensation section 44b of the ebullient cooler <NUM> is also accommodated in the internal space 48a of the floor tunnel <NUM>.

As illustrated in <FIG>, in the internal space 48a of the floor tunnel <NUM>, the inverter <NUM> is particularly arranged above the torque tube <NUM>. Particularly, at the position above the torque tube <NUM>, the inverter <NUM> is arranged along a longitudinal direction of the torque tube <NUM>. The inverter <NUM> particularly has a terminal 27a in a front portion thereof.

One or more, particularly three wire harnesses <NUM> are connected to the terminal 27a. Each of the three wire harnesses <NUM> is a flexible connection wire and electrically connects the inverter <NUM> and the motor <NUM>. The terminal 27a corresponds to an "output terminal".

Particularly, as illustrated in <FIG>, in the internal space 48a of the floor tunnel <NUM>, the inverter <NUM> is attached to the floor tunnel <NUM> via a bracket <NUM>. A clearance is provided between the inverter <NUM> and the torque tube <NUM>. The propeller shaft <NUM> is particularly accommodated in the internal space 47a of the torque tube <NUM>.

Here, even in the case where the torque tube <NUM> vibrates with the drive unit <NUM> during driving of the drive unit <NUM>, the vibration is not directly transmitted to the inverter <NUM> due to the clearance between the inverter <NUM> and the torque tube <NUM>.

In addition, as described above, while the drive unit <NUM> is attached to the front subframe, the inverter <NUM> is attached to the floor tunnel <NUM> that is separated from the first position. Accordingly, even when the vibration is generated during driving of the drive unit <NUM>, the transmission of the vibration from the drive unit <NUM> to the inverter <NUM> via an attachment position in the vehicle body is suppressed.

The front subframe corresponds to the "first position of the vehicle body", and the portion formed with the floor tunnel in the floor panel corresponds to a "second position of the vehicle body".

A description will be made on an arrangement structure of the wire harnesses <NUM> with reference to <FIG> and <FIG>.

As illustrated in <FIG> and <FIG>, the terminal 27a of the inverter <NUM> and a terminal (an input terminal) 14e of the motor <NUM> are particularly connected by the three wire harnesses <NUM>. The terminal 14e of the motor <NUM> is particularly disposed on the side housing 14b of the motor <NUM>. As illustrated in <FIG>, the terminal 27a as the output terminal of the inverter <NUM> and the terminal 14e as the input terminal of the motor <NUM> are arranged to have such a positional relationship that the terminal 27a and the terminal 14e oppose each other in the longitudinal direction of the vehicle <NUM>.

As illustrated in <FIG>, an end of each of the three wire harnesses <NUM> is particularly connected to respective one of connection portions 27a1 to 27a3 provided to the terminal 27a of the inverter <NUM>. In the case where an imaginary straight line L<NUM> that runs through the connection portions 27a1 to 27a3 is assumed, the connection portions 27a1 to 27a3 are disposed such that the imaginary straight line L<NUM> is oriented in an oblique direction at an angle θ<NUM> with respect to a center axis L<NUM> of the drive unit <NUM>. The angle θ<NUM> is an obtuse angle that is particularly larger than <NUM>°. Each of the connection portions 27a1 to 27a3 corresponds to a "first connection portion", and the imaginary straight line L<NUM> corresponds to a "first imaginary straight line".

Each of the three wire harnesses <NUM> particularly extends obliquely to the left in the vehicle <NUM> from the terminal 27a (arrows A1 to A3).

The other end of each of the three wire harnesses <NUM> is connected to respective one of connection portions 14e1 to 14e3 that are provided to the terminal 14e of the motor <NUM>. In the case where an imaginary straight line L<NUM> that runs through the connection portions 14e1 to 14e3 is assumed, the connection portions 14e1 to 14e3 are disposed such that the imaginary straight line L<NUM> is oriented at an angle θ<NUM> with respect to the center axis L<NUM> of the drive unit <NUM>. Particularly, the angle θ<NUM> is approximately <NUM>°. Each of the connection portions 14e1 to 14e3 corresponds to a "second connection portion", and the imaginary straight line L<NUM> corresponds to a "second imaginary straight line".

Each of the three wire harnesses <NUM> particularly extends obliquely to the left in the vehicle <NUM> from the terminal 14e (arrows B1 to B3).

Particularly, as illustrated in <FIG>, each of the three wire harnesses <NUM> has a wire length that is longer than a linear distance between respective one of the connection portions 27a1 to 27a3 of the terminal 27a and respective one of the connection portions 14e1 to 14e3 of the terminal 14e. Accordingly, the three wire harnesses <NUM> are arranged in a curved state so as to run around an area between the terminal 27a and the terminal 14e. In the area that is run around by the wire harnesses <NUM>, the condensation section 44b of the ebullient cooler <NUM> is particularly disposed. In addition, since the wire harnesses <NUM> are arranged to be curved to the left, it is possible to dispose the pipes 44c of the ebullient cooler <NUM> on the right side. In this way, it is possible to attach the inverter <NUM> and the ebullient cooler <NUM> to the drive unit <NUM> with high space efficiency and to downsize the drive unit <NUM>, the inverter <NUM>, and the ebullient cooler <NUM> as a whole.

As illustrated in <FIG>, the three wire harnesses <NUM> are particularly arranged to run above the torque tube <NUM> so as not to contact the torque tube <NUM>. In addition, the three wire harnesses <NUM> are particularly arranged within an outer circumference D of the engines <NUM> to <NUM> in the drive unit <NUM>. In particular, the three wire harnesses <NUM> are arranged to run above upper ends of the engines <NUM> to <NUM> and below an imaginary straight line Lu drawn in the longitudinal direction of the vehicle <NUM>. In this way, the wire harnesses <NUM> can fit within the internal space 48a of the floor tunnel <NUM> without increasing size of the floor tunnel <NUM> in a cross-sectional direction.

As illustrated in <FIG>, the three wire harnesses <NUM> are particularly arranged with clearances interposed therebetween and not to cross each other. In this way, the three wire harnesses <NUM> are prevented from contacting each other, which suppresses damage to coated portions, and the like.

In the above embodiment, as illustrated in <FIG>, the wire harnesses <NUM> are arranged to be curved to the left. However, in the present invention, the wire harnesses <NUM> may be arranged to be curved to the right.

In the above embodiment, the inverter <NUM> is attached to the floor tunnel <NUM>. However, the present invention is not limited thereto. When the inverter is attached to a different position from the position, to which the drive unit in the vehicle body is attached, the same effects as above can be exerted.

In the above embodiment, an AC motor is adopted as the motor <NUM>, and thus the inverter <NUM> is provided between the battery <NUM> and the motor <NUM>. However, in the present invention, any of various power converters can be provided according to the type of the motor. For example, in the case where a DC/DC converter (a DC chopper) or the like is adopted, by adopting the same connection wires as those in the above embodiment, the same effects as above can be exerted.

In the above embodiment, the drive unit <NUM>, which is configured to include the three engines <NUM> to <NUM> and the single motor <NUM>, is adopted. However, the present invention is not limited thereto. For example, a drive unit configured to include a single engine and a single motor or a drive unit configured to include a plurality of engines and a plurality of motors can be adopted.

In the above embodiment, each of the engines <NUM> to <NUM> is the rotary engine. However, a reciprocating engine can be adopted in the present invention. However, in the above embodiment in which the rotary engine is adopted, the drive unit <NUM> can be downsized, and the drive unit <NUM> can be arranged in the area near the center of the vehicle <NUM>. Thus, the adoption of the rotary engines as the engines <NUM> to <NUM> in the vehicle <NUM> is beneficial for achieving higher vehicle motion performance. However, the rotary engine is of a high-speed type and thus generates significant vibration at the time of driving. Meanwhile, when the inverter and the connection wires are configured as in the above embodiment, it is possible to suppress damage to the inverter and the connection wires.

In the above embodiment, an FR vehicle is adopted as an example of the vehicle <NUM>. However, the present invention is not limited thereto. For example, an RR vehicle, in which the drive unit is mounted in a rear portion and transmits the drive power to rear wheels, an MR vehicle, in which the drive unit is mounted to a position behind a driver's seat to transmit the drive power to rear wheels, or further an FF vehicle, in which the drive unit is mounted to a rear portion of a front area to transmit the drive power to front wheels, can be adopted.

Claim 1:
A vehicle (<NUM>) comprising:
a drive unit (<NUM>) that has an engine (<NUM>, <NUM>, <NUM>) and a motor (<NUM>) and is a drive source for travel of the vehicle (<NUM>);
an inverter (<NUM>) configured to convert a direct current into an alternating current and output the alternating current; and
a connection wire (<NUM>) configured to electrically connect an output terminal (27a) of the inverter (<NUM>) and an input terminal (14e) of the motor (<NUM>), wherein
the inverter (<NUM>) is arranged separately from the drive unit (<NUM>), and
the connection wire (<NUM>) has flexibility and/or is formed of a wire harness, a wire length of which is longer than a linear distance between the output terminal (27a) of the inverter (<NUM>) and the input terminal (14e) of the motor (<NUM>),
characterized in that the vehicle (<NUM>) further comprises:
a shaft (<NUM>) that is coupled to an output shaft of the drive unit (<NUM>) and configured to transmit drive power to a drive wheel (<NUM>, <NUM>); and
a cover member (<NUM>) configured to cover the periphery of the shaft (<NUM>), and
the inverter (<NUM>) is arranged separately from the cover member (<NUM>).