Patent ID: 12214666

DETAILED DESCRIPTION

Next, a vehicle driving apparatus according to an embodiment of the present disclosure will be described with reference to the attached drawings.

FIG.1is a perspective view illustrating a state where the vehicle driving apparatus according to an embodiment of the present disclosure is installed in a vehicle.FIG.2is a plan view illustrating a state where the vehicle driving apparatus according to an embodiment of the present disclosure is installed in the vehicle.FIG.3is a cross-sectional view illustrating internal structures of a drive motor, a generator, and an electric power conversion apparatus casing in the vehicle driving apparatus according to an embodiment of the present disclosure as seen from a forward side of the vehicle. Note that inFIG.1toFIG.3, an intake pipe and an exhaust pipe that extend from an internal combustion engine can be included.

First, a description will be made about an arrangement structure of each configuration in a vehicle driving apparatus1according to the present embodiment with reference toFIG.1toFIG.3.

In the vehicle driving apparatus1according to the present embodiment, an internal combustion engine2, a drive motor4, a generator6as an electrical generator, an electric power conversion apparatus casing8a,and a reduction gear10as a speed reduction mechanism reducing a speed of a rotation output of the drive motor4are integrally formed. Note that as described later, in the present embodiment, an inverter8band a converter8c(FIG.3) as electric power conversion apparatuses are built in the electric power conversion apparatus casing8a.Further, as described later, in the present embodiment, a drive shaft12(FIG.2) of the vehicle is driven by a driving force of the drive motor4but is not directly driven by motive power generated by the internal combustion engine2.

Further, as illustrated inFIG.1andFIG.2, the vehicle driving apparatus1is housed in a motor room11ain a front portion of a vehicle11, and this motor room11ais covered by a bonnet11b. Further, the drive motor4, the reduction gear10(FIG.2), the internal combustion engine2, and the generator6, which constitute the vehicle driving apparatus1, are arranged in this order in a vehicle width direction of the vehicle11. That is, the vehicle driving apparatus1is arranged between body side frames11con both sides of the vehicle11and below the bonnet11b.

In addition, the vehicle driving apparatus1according to the present embodiment includes a radiator14dedicated to the internal combustion engine for cooling the internal combustion engine2, an oil cooler18(FIG.2), and a radiator16dedicated to the electric power conversion apparatuses. Note that the radiator16dedicated to the electric power conversion apparatuses is configured to cool the electric power conversion apparatuses, and the oil cooler18is configured to cool the drive motor4and the generator6.

The internal combustion engine2is configured to generate motive power by combusting fuel loaded on the vehicle, an input shaft of the generator6is driven by the motive power generated by the internal combustion engine2, and electric power is thereby generated. The electric power generated by the generator6is accumulated as electrical energy in a lithium-ion battery20(FIG.2) as a storage battery. Note that in the present embodiment, a rotary piston engine is employed as the internal combustion engine2.

The drive motor4is configured to be driven by the electrical energy accumulated in the lithium-ion battery20and to drive the drive shaft12of the vehicle11. An output shaft of the drive motor4is connected with an input shaft of the reduction gear10as the speed reduction mechanism, and a rotation output of the drive motor4drives the drive shaft12via the reduction gear10. Further, the drive motor4is configured to perform regeneration of electrical energy from kinetic energy of the vehicle and to thereby generate alternating current electric power when the vehicle11is decelerated. In the present embodiment, a permanent magnet motor driven by alternating current is employed as the drive motor4.

The generator6is configured to generate alternating current electric power by motive power generated by the internal combustion engine2, and the input shaft thereof is driven to be rotated by an output shaft of the internal combustion engine2. The alternating current electric power generated by the generator6is converted to a direct current by the converter8cin the electric power conversion apparatus casing8aand is accumulated in the lithium-ion battery20.

The reduction gear10is a speed reduction mechanism arranged between the drive motor4and the internal combustion engine2in a width direction of the vehicle11and is provided in a halfway portion of a transmission path for transmitting motive power of the drive motor4to wheels of the vehicle11. The reduction gear10performs speed reduction for rotation of an output shaft4d(FIG.3) of the drive motor4, and the rotation is transmitted to the wheels (not illustrated) via the drive shaft12. Note that in the present embodiment, the reduction gear10is employed as a speed reduction mechanism, but a transmission having a speed change function may be employed as a speed reduction mechanism.

The electric power conversion apparatus casing8ais a casing of the electric power conversion apparatuses, and in its internal portion, the inverter8band the converter8c(FIG.3) as the electric power conversion apparatuses are built in the integral casing. Further, the inverter8bis configured to convert direct current electric power supplied from the lithium-ion battery20to alternating current electric power. The converter8cis configured to convert alternating current electric power generated by the generator6and alternating current electric power regenerated by the drive motor4to direct current electric power. The electric power converted to an alternating current by the inverter8bis supplied to the drive motor4, and the drive motor4is driven. Further, the electric power converted to a direct current by the converter8cis charged to the lithium-ion battery20. Note that in the electric power conversion apparatus casing8a,a DC-DC converter (not illustrated) boosting and/or dropping a direct current voltage or a junction box may be built.

Further, the electric power conversion apparatus casing8ais arranged above the drive motor4, the reduction gear10, the internal combustion engine2, and the generator6and is arranged to overlap with those in a planar view (top view). In addition, the electric power conversion apparatus casing8a,a casing of the drive motor4, and a casing of the generator6are joined together and form an integrated casing. Here, in general, a motor, a generator, and electric power conversion apparatuses are respectively housed in independent casings, and those casings are electrically connected together by wire harnesses. On the other hand, in the vehicle driving apparatus1of the present embodiment, the drive motor4, the generator6, and the electric power conversion apparatus casing8aare integrated, and wire harnesses for connecting those together are not provided. Thus, conductors extending in an internal portion of the integrated casing respectively connect the electric power conversion apparatus casing8awith the drive motor4and the electric power conversion apparatus casing8awith the generator6.

Further, as illustrated inFIG.2, a center C1of the electric power conversion apparatus casing8ain the vehicle width direction is positioned on a side where the drive motor4is arranged with respect to a central axis line C2of the vehicle11that extends in a front-rear direction of the vehicle11. Thus, the overlapping amount (hatched part S1inFIG.2) between the drive motor4and the electric power conversion apparatus casing8ais larger than the overlapping amount (hatched part S2inFIG.2) between the generator6and the electric power conversion apparatus casing8a.That is, the vehicle driving apparatus1of the present embodiment, the ratio of the weight occupied by the internal combustion engine2to the whole weight is high. Thus, the position of the center of gravity of the whole vehicle driving apparatus1tends to deviate to a side where the internal combustion engine2is arranged with respect to the central axis line C2of the vehicle11. In the present embodiment, the center C1of the electric power conversion apparatus casing8ais positioned on the side where the drive motor4is arranged with respect to the central axis line C2of the vehicle11, and deviation in weight balance of the vehicle driving apparatus1is thereby inhibited.

As illustrated inFIG.2, the radiator14dedicated to the internal combustion engine is a flat-plate-shaped heat exchanger arranged on a front side of the vehicle relative to the internal combustion engine2and is configured such that traveling air contacts with a plate surface of the heat exchanger due to traveling of the vehicle and heat of a cooling liquid is dissipated to the atmosphere. Further, the internal combustion engine2and the radiator14dedicated to the internal combustion engine are connected together by piping for the cooling liquid and are configured such that the cooling liquid circulates between the radiator14dedicated to the internal combustion engine and the internal combustion engine2. That is, the cooling liquid whose temperature is raised by cooling the internal combustion engine2is sent to the radiator14dedicated to the internal combustion engine, causes its heat to be dissipated, causes its temperature to be lowered there, and is thereafter returned to the internal combustion engine2.

The radiator16dedicated to the electric power conversion apparatuses is a long and narrow flat-plate-shaped heat exchanger arranged on the front side of the vehicle relative to the radiator14dedicated to the internal combustion engine and is configured such that traveling air of the vehicle contacts with a plate surface of the heat exchanger and heat of a cooling liquid is dissipated to the atmosphere. Further, the electric power conversion apparatus casing8aand the radiator16dedicated to the electric power conversion apparatuses are connected together by an inflow pipe16aand an outflow pipe16band are configured such that the cooling liquid circulates. That is, the cooling liquid whose temperature is raised by cooling the electric power conversion apparatuses in the electric power conversion apparatus casing8aflows into the radiator16dedicated to the electric power conversion apparatuses via the inflow pipe16a.The cooling liquid flowing thereinto causes its heat to be dissipated in the radiator16dedicated to the electric power conversion apparatuses, and the cooling liquid whose temperature is lowered is returned to the electric power conversion apparatus casing8avia the outflow pipe16band again cools the electric power conversion apparatuses.

The oil cooler18is a long and narrow flat-plate-shaped heat exchanger arranged on a lower side of the radiator14dedicated to the internal combustion engine and is configured such that traveling air of the vehicle contacts with a plate surface of the heat exchanger and heat of a cooling liquid is dissipated to the atmosphere. Piping connects the oil cooler18with the drive motor4and the oil cooler18with the generator6. In addition, the generator6and the drive motor4are connected together by a transfer pipe. That is, the cooling liquid whose temperature is raised by cooling the drive motor4flows into the oil cooler18, heat of the cooling liquid flowing thereinto is dissipated in the oil cooler18, the cooling liquid whose temperature is lowered is returned to the generator6, and the generator6is cooled. The cooling liquid cooling the generator6is sent to the drive motor4via the transfer pipe, and the drive motor4is cooled.

The electric power conversion apparatuses in the electric power conversion apparatus casing8aare cooled by the radiator16dedicated to the electric power conversion apparatuses, and a water-based cooling liquid circulates between the electric power conversion apparatus casing8aand the radiator16dedicated to the electric power conversion apparatuses and cools the electric power conversion apparatuses. That is, hot water whose temperature is raised by cooling the electric power conversion apparatuses is sent to the radiator16dedicated to the electric power conversion apparatuses and is cooled. In addition, cold water whose temperature is lowered by being cooled by the radiator16dedicated to the electric power conversion apparatuses is returned to the electric power conversion apparatus casing8aand cools the electric power conversion apparatuses in the internal portion thereof.

Next, again referring toFIG.3, a description will be made about connection structures of the drive motor4, the generator6, and the electric power conversion apparatus casing8ain the vehicle driving apparatus1of the present embodiment.

FIG.3is a cross-sectional view illustrating internal structures of the drive motor4, the generator6, and the electric power conversion apparatus casing8a.

As illustrated inFIG.3, the drive motor4has a motor casing4aas a casing of the drive motor4, a rotor4band a stator4cthat are housed in this motor casing4a,and the output shaft4d.The rotor4bis joined to the output shaft4ddirected in the horizontal direction and is supported rotatably around, as a center, a horizontal axis line with respect to the motor casing4a. The stator4cis fixed to the motor casing4aand is configured to rotate and drive the rotor4bby causing an alternating current to flow through a coil constituting the stator4c.Meanwhile, in deceleration, the output shaft4dis driven to be rotated on kinetic energy carried by the vehicle. Accordingly, because the rotor4bis driven to be rotated together with the output shaft4d,an induced current is produced in the stator4c,and the kinetic energy of the vehicle is regenerated as electrical energy.

The generator6has a generator casing6aas a casing of the generator6, a rotor6band a stator6cthat are housed in this generator casing6a,and an input shaft6d.The rotor6bis joined to the input shaft6ddirected in the horizontal direction and is supported rotatably around, as a center, a horizontal axis line with respect to the generator casing6a.The stator6cis fixed to the generator casing6aand is configured such that when the rotor6bis driven to be rotated by a driving force of the internal combustion engine2, an induced current flows through a coil constituting the stator6c,and alternating current electric power is generated.

In the electric power conversion apparatus casing8a,the inverter8band the converter8care housed and integrated as an electric drive system unit. The inverter8band converter8care formed of circuit substrates including electric power semiconductor elements such as an IGBT (insulated-gate bipolar transistor) and a MOSFET (MOS field-effect transistor) for switching and a diode for rectification. Note that depending on a configuration of an electric drive system of the vehicle, a DC-DC converter converting a direct current voltage may be included in the electric power conversion apparatus casing8a.

In addition, because the electric power semiconductor element on the circuit substrate produces heat when operating, in order to cool this, a cooling liquid chamber8dis provided in the electric power conversion apparatus casing8a.The inflow pipe16aand the outflow pipe16bare connected with this cooling liquid chamber8d,and a cooling liquid different from the cooling liquid circulating in the oil cooler18is caused to circulate between the cooling liquid chamber8dand the radiator16dedicated to the electric power conversion apparatuses (FIG.1). As described above, the cooling liquid is caused to circulate in the cooling liquid chamber8d,the cooling liquid chamber8dthereby acts as a water jacket, and the inverter8band the converter8cin the electric power conversion apparatus casing8aare cooled. Further, so that the cooling liquid is caused to efficiently flow in the cooling liquid chamber8d,wall surfaces in the cooling liquid chamber8dare formed flat.

Further, one end portion of a bottom surface of the electric power conversion apparatus casing8ais fastened and fixed to an upper end portion of the motor casing4aof the drive motor4and is integrated together. In addition, another end portion of the bottom surface of the electric power conversion apparatus casing8ais fastened and joined to an upper end portion of the generator casing6aof the generator6and is integrated together so as to straddle over the reduction gear10and the internal combustion engine2. As described above, in the present embodiment, the electric power conversion apparatus casing8a,the motor casing4a,and the generator casing6athat are configured as separate bodies are fastened together, and an integrated casing is thereby configured; however, a portion or all of those casings may integrally be molded.

Here, as described above, the electric power supplied from the lithium-ion battery20is supplied to the drive motor4via the inverter8bin the electric power conversion apparatus casing8a.Thus, plural bus bars24as first conductors for connecting the inverter8bwith the drive motor4extend in an internal portion of the motor casing4aand the electric power conversion apparatus casing8athat are integrated. Further, the alternating current electric power regenerated by the drive motor4is charged to the lithium-ion battery20via the converter8c.Thus, the bus bars24extending in the internal portion of the motor casing4aand the electric power conversion apparatus casing8athat are integrated are used also when the alternating current electric power regenerated by the drive motor4is supplied to the converter8c.Accordingly, a harness or the like is not provided that is for delivery and reception of electric power between the drive motor4and the electric power conversion apparatuses and passes through external portions of the motor casing4aand the electric power conversion apparatus casing8a.

Similarly, the alternating current electric power generated by the generator6is charged to the lithium-ion battery20via the converter8cin the electric power conversion apparatus casing8a.Thus, plural bus bars26as second conductors for connecting the generator6with the converter8calso extend in an internal portion of the generator casing6aand the electric power conversion apparatus casing8athat are integrated. Accordingly, a harness or the like is not provided that is for delivery and reception of electric power between the generator6and the electric power conversion apparatus (converter8c) and passes through external portions of the generator casing6aand the electric power conversion apparatus casing8a.

Next, a description will be made about connection of an intake pipe and an exhaust pipe to the internal combustion engine with reference toFIG.4andFIG.5.

FIG.4is a perspective view of the vehicle driving apparatus1according to an embodiment of the present invention as seen from an obliquely rearward left side.FIG.5is a side cross-sectional view of the vehicle driving apparatus1according to an embodiment of the present disclosure as seen from a left side.

As illustrated inFIG.4andFIG.5, in the internal combustion engine2included in the vehicle driving apparatus1, to a side surface thereof on a rear side in the front-rear direction of the vehicle11, an intake pipe2aand an exhaust pipe2bare connected.

The intake pipe2afirst extends from an upper portion of a side surface on a rear side of the internal combustion engine2(on a rearward side of the vehicle11) to the rearward side of the vehicle11and thereafter extends to a front side of the internal combustion engine2while passing above the internal combustion engine2and the generator6. Further, the drive shaft12extends on the rear side of the internal combustion engine2while crossing the vehicle11, and the intake pipe2ais connected with the internal combustion engine2on an upper side of the drive shaft12. In addition, an air cleaner28is provided in a distal end portion of the intake pipe2aand is configured to remove dust in air to be taken into the internal combustion engine2.

Meanwhile, the exhaust pipe2bextends from a lower portion on the side surface on the rear side of the internal combustion engine2(on the rearward side of the vehicle11) to the rearward side of the vehicle11and is inserted into a tunnel portion provided at a center of a lower portion of the vehicle11. Further, a catalyzer (catalytic converter)30is provided in a halfway portion of this exhaust pipe2band is configured to remove harmful components in exhaust gas. Further, the exhaust pipe2bis connected with the internal combustion engine2on a lower side of the drive shaft12on the rear side of the internal combustion engine2, first extends downward to bypass the drive shaft12, thereafter extends upward, and is connected with the catalyzer30. Thus, as illustrated inFIG.5, the drive shaft12extends in the width direction of the vehicle11through a portion between the intake pipe2aand the exhaust pipe2bthat extend from the internal combustion engine2to the rearward side of the vehicle11. Accordingly, the internal combustion engine2and its intake pipe2aand exhaust pipe2bcan efficiently be accommodated in the narrow motor room11aon a lower side of the bonnet11b.

In the vehicle driving apparatus1of an embodiment of the present disclosure, in the vehicle width direction of the vehicle11, the drive motor4, the internal combustion engine2, and the generator6are arranged in this order (FIG.2). As a result, because the internal combustion engine2with a comparatively large weight is positioned between the drive motor4and the generator6, the weight balance between left and right of the vehicle11is less likely to be unstable, and the weight balance can be inhibited from being deteriorated. Further, because the internal combustion engine2is positioned between the drive motor4and the generator6, the internal combustion engine2is positioned on a comparatively inner side in the vehicle width direction, inertia moments around a yaw axis and around a roll axis of the vehicle11can be lowered, and lowering of motion performance can thereby be inhibited.

Further, in the vehicle driving apparatus1of the present embodiment, because a rotary piston engine is employed as the internal combustion engine2, the internal combustion engine2is less likely to be bulky in the motor room11aeven when being arranged between the drive motor4and the generator6. Thus, even when the internal combustion engine2is arranged between the drive motor4and the generator6, a space in the motor room11acan effectively be utilized.

In addition, in the vehicle driving apparatus1of the present embodiment, a rotary piston engine is employed as the internal combustion engine2, and the intake pipe2aand the exhaust pipe2bextend rearward from a rear side of the rotary piston engine (FIG.4). Accordingly, routing of the intake pipe2aand the exhaust pipe2bcan be simplified, and intake efficiency and exhaust efficiency can be improved.

Further, in the vehicle driving apparatus1of the present embodiment, because the reduction gear10is arranged between the drive motor4and the internal combustion engine2in the vehicle width direction of the vehicle11, speed reduction can be performed by easily connecting an output of the drive motor4to the reduction gear10.

In addition, in the vehicle driving apparatus1of the present embodiment, the bus bars24are arranged in the internal portion of the electric power conversion apparatus casing8aand the casing of the drive motor4, and the bus bars26are arranged in the internal portion of the electric power conversion apparatus casing8aand the casing of the generator6(FIG.3). Thus, an insulating material for securing insulation of each of the bus bars extending in the internal portions of the casings can be simplified compared to insulating materials for harnesses connecting electric devices in external portions of casings. Accordingly, costs required for insulating materials and weights can be reduced.

Further, in the vehicle driving apparatus1of the present embodiment, because the center C1of the electric power conversion apparatus casing8ais positioned on the side where the drive motor4is arranged with respect to the central axis line C2of the vehicle11(FIG.2), the weight balance of the whole vehicle driving apparatus1can further be improved.

In addition, in the vehicle driving apparatus1of the present embodiment, because the electric power conversion apparatus casing8aand the casing of the drive motor4are joined together and the inverter8bis included as the electric power conversion apparatus, direct current electric power supplied from the lithium-ion battery20or the like can be converted to an alternating current and can be supplied to the drive motor4in a short distance. Accordingly, the alternating-current drive motor4can be operated in a compact configuration. Further, because the electric power conversion apparatus casing8aand the casing of the generator6are joined together and the converter8cis included as the electric power conversion apparatus, alternating current electric power generated by the generator6can easily be converted to a direct current. Accordingly, an output of the alternating-current generator6can be charged to a battery or the like in a compact configuration.

Further, in the vehicle driving apparatus1of the present embodiment, an overlapping amount S1between the drive motor4and the electric power conversion apparatus casing8ais configured to be larger than an overlapping amount S2between the generator6and the electric power conversion apparatus casing8a.Thus, the electric power conversion apparatus casing8ais arranged, the center of gravity of the vehicle driving apparatus1can thereby be moved to the drive motor4side, and the weight balance of the whole vehicle driving apparatus1can further be improved.

In addition, in the vehicle driving apparatus1of the present embodiment, because the drive motor4, the internal combustion engine2, and the generator6are arranged below the bonnet11b, a space below the bonnet11bcan effectively be utilized.

In the above, an embodiment of the present disclosure is described, but various changes may be added to the above-described embodiment. That is, in the above-described embodiment, the internal combustion engine drives the generator, and the drive shaft is not directly driven by the internal combustion engine; however, the present disclosure can be applied to a vehicle driving apparatus in which a drive shaft is driven by motive power of an internal combustion engine. Further, the present disclosure can also be applied to a vehicle driving apparatus whose battery is principally charged by an external electric power source. In addition, in the above-described embodiment, a rotary piston engine is employed as the internal combustion engine; however, various types of engines can be employed as the internal combustion engine. For example, a horizontally opposed engine can be employed as the internal combustion engine. This horizontally opposed engine has a low overall height similarly to a rotary piston engine and is suitable because the space factor in the motor room is not decreased even in a case where the casings of the electric power conversion apparatuses and so forth are arranged above the internal combustion engine.

Next, a vehicle driving apparatus1aaccording to another exemplary embodiment of the present disclosure will be described with reference toFIG.6toFIG.8.FIG.6is a plan view (top view) illustrating a state where the vehicle driving apparatus1aaccording to the other exemplary embodiment of the present disclosure is installed in a vehicle.FIG.7is a plan view (top view) of the vehicle driving apparatus1aaccording to the other exemplary embodiment of the present disclosure. ThisFIG.7illustrates only main parts among components illustrated inFIG.6).FIG.8is a front view of the vehicle driving apparatus1aaccording to the other exemplary embodiment of the present disclosure. ThisFIG.8also illustrates only main parts among the components illustrated inFIG.6(different fromFIG.7,FIG.8illustrates the inverter8b,the air cleaner28, and so forth).

As illustrated inFIG.6, similarly to the vehicle driving apparatus1according to the above-described embodiment, in the vehicle driving apparatus1aaccording to the other exemplary embodiment of the present invention, the drive motor4, the reduction gear10, the internal combustion engine2, and the generator6are arranged in this order in the vehicle width direction. However, the vehicle driving apparatus1adoes not include the electric power conversion apparatus casing8aas in the vehicle driving apparatus1, but the inverter8b,the converter8c,and so forth are separately arranged. Specifically, in the vehicle driving apparatus1a, the inverter8bis arranged above the drive motor4, and the converter8cis arranged above the internal combustion engine2. Further, in the vehicle driving apparatus1a, a junction box8eis arranged on the inverter8b(seeFIG.8), the junction box8ehousing terminals and so forth for joining, branching, and relaying electric wires of the inverter8b,the converter8c,the lithium-ion battery20, and so forth. In addition, as indicated by broken lines inFIG.6, the generator6, the converter8c,the junction box8e,and the lithium-ion battery20are electrically connected together in this order. Note that as the reduction gear10, a transaxle may be used that includes a speed reduction mechanism and a differential mechanism.

Further, as illustrated inFIG.8, in the vehicle driving apparatus1aaccording to the other exemplary embodiment, in a front view, an oil pan2dis provided in a lower portion of an internal combustion engine body2c, and an output shaft2x(see broken lines inFIG.8) of the internal combustion engine2is arranged to be offset to a vehicle upward side with respect to the output shaft4d(see broken lines inFIG.8) of the drive motor4. The output shaft2xof the internal combustion engine2is arranged to be offset above the vehicle relative to the output shaft4dof the drive motor4as described above, and a capacity of the oil pan2din the lower portion of the internal combustion engine body2ccan thereby appropriately be secured. Note that usually, the output shaft2xof the internal combustion engine2is arranged in a general center position of the internal combustion engine2in a vehicle up-down direction (the center position between an upper end and a lower end of the internal combustion engine2), and the output shaft4dof the drive motor4is arranged in a general center position of the drive motor4in the vehicle up-down direction (the central position between an upper end and a lower end of the drive motor4). Thus, when the output shaft2xof the internal combustion engine2is arranged to be offset upward with respect to the output shaft4dof the drive motor4, the center position of the internal combustion engine2in the vehicle up-down direction is positioned above the center position of the drive motor4in the vehicle up-down direction.

Meanwhile, because the output shaft2xof the internal combustion engine2and the input shaft6dof the generator6are coupled together, those output shaft2xand input shaft6dare positioned on generally the same axis line (see broken lines inFIG.7andFIG.8).

Further, as illustrated inFIG.7, in a planar view, a front end portion of the internal combustion engine2is positioned on a vehicle forward side of a front end portion of the drive motor4. Accordingly, in a collision of a vehicle front portion, an object moving from the front toward the vehicle driving apparatus1acan be caused to contact with the internal combustion engine2earlier than the drive motor4, and the drive motor4can thereby appropriately be protected by the internal combustion engine2.

Further, as illustrated inFIG.7, in a planar view, the output shaft2x(see the broken lines inFIG.7) of the internal combustion engine2is arranged to be offset to the vehicle forward side with respect to the output shaft4d(see the broken lines inFIG.7) of the drive motor4, and a heat exchanger2eas an auxiliary device (engine auxiliary device) of the internal combustion engine2is mounted on a front portion of the internal combustion engine body2cin front of the drive motor4and the reduction gear10(seeFIG.8also). Usually, the output shaft2xof the internal combustion engine2is arranged in a general center position of the internal combustion engine2in the vehicle front-rear direction (the center position between a right end and a left end of the internal combustion engine2), and the output shaft4dof the drive motor4is arranged in a general center position of the drive motor4in the vehicle front-rear direction (the central position between a right end and a left end of the drive motor4). Thus, when the output shaft2xof the internal combustion engine2is arranged to be offset forward with respect to the output shaft4dof the drive motor4, the center position of the internal combustion engine2in the vehicle front-rear direction is positioned in front of the center position of the drive motor4in the vehicle front-rear direction.

The heat exchanger2ehas an oil cooler for cooling oil, a water pump for supplying water for cooling the oil to the oil cooler, an oil filter for removing impurities in the oil, and so forth. Although the water pump is driven by the output shaft2xof the internal combustion engine2, because its vehicle-width-direction dimension becomes large when a shaft of the water pump is arranged on the same axis line as the output shaft2x,the shaft of the water pump is arranged to be shifted from the output shaft2x(in this case, motive power is transmitted from the output shaft2xto the shaft of the water pump via a chain). Thus, the heat exchanger2eincluding the water pump is provided on a vehicle-width-direction inner side with respect to the internal combustion engine body2c.Accordingly, the heat exchanger2eis positioned in front of the drive motor4and the reduction gear10.

After all, the output shaft2xof the internal combustion engine2is arranged to be offset in front of the vehicle relative to the output shaft4dof the drive motor4, and a space can thereby be formed in front of the drive motor4and the reduction gear10. In the other exemplary embodiment, by using such a space, the above-described heat exchanger3eis arranged (specifically, the heat exchanger2eis arranged to overlap with the reduction gear10in a front view). Accordingly, an increase in a dimension of the vehicle driving apparatus1ain the vehicle width direction can appropriately be inhibited. Further, the heat exchanger2eis arranged in front of the drive motor4and the reduction gear10, in a collision of the vehicle front portion, an object moving from the front toward the vehicle driving apparatus1acan be caused to contact with the heat exchanger2eearlier than the drive motor4and the reduction gear10, and the drive motor4and the reduction gear10can thereby appropriately be protected by the heat exchanger2e.

Note that the auxiliary device of the internal combustion engine2is not limited to use of the above-described heat exchanger2e.The auxiliary device of the internal combustion engine2is a device necessary for operating the internal combustion engine2, for example. In other examples, an electrical generator (alternator), an injection pump, and so forth that are driven by motive power produced by the internal combustion engine2can be applied.

Further, as illustrated inFIG.6andFIG.7, in the vehicle driving apparatus1aaccording to the other exemplary embodiment, the converter8cis arranged to overlap with an upper surface of the internal combustion engine2in a planar view. Specifically, an outer side end of the converter8cin the vehicle width direction is positioned on an inner side of an outer side end of the internal combustion engine2in the vehicle width direction, and a front end portion of the converter8cis positioned on a vehicle rearward side of the front end portion of the internal combustion engine2. Accordingly, in a planar view, the whole converter8coverlaps on the internal combustion engine2(FIG.7). The converter8cis arranged as described above, and in a collision of the vehicle front portion, the body side frame11cor the like that is deformed can thereby be inhibited from interfering with the converter8c. Specifically, in a collision of the vehicle front portion, the deformed body side frame11cor the like can be caused to contact with the internal combustion engine2earlier than the converter8c,and the converter8ccan thereby appropriately be protected by the internal combustion engine2.

Further, as illustrated inFIG.6andFIG.8, in a planar view, the inverter8band the junction box8eare arranged to overlap with an upper surface of the drive motor4. Specifically, such that outer side ends of the inverter8band the junction box8ein the vehicle width direction are positioned on an inner side of an outer side end of the drive motor4in the vehicle width direction, those are arranged on the drive motor4. Accordingly, in a collision of the vehicle front portion, the inverter8band the junction box8ecan thereby appropriately be protected by the drive motor4.

Further, as illustrated inFIG.6andFIG.8, the air cleaner28on the generator6is arranged to be offset outward in the vehicle width direction with respect to the converter8c.Accordingly, in a collision of the vehicle front portion, the damaged air cleaner28can appropriately be inhibited from interfering with the converter8c.In addition, the intake pipe2aconnecting the air cleaner28and the internal combustion engine2together is separately arranged from the converter8c. Specifically, the intake pipe2ais arranged with respect to the converter8csuch that the intake pipe2adoes not overlap with the converter8cin a planar view (FIG.6) and the intake pipe2adoes not overlap with the converter8cin a front view (FIG.8). Accordingly, in a collision of the vehicle front portion, the damaged intake pipe2acan appropriately be inhibited from interfering with the converter8c.

Advantageous Effect of Disclosure

A vehicle driving apparatus according to the present invention includes a drive motor, an internal combustion engine, and an electrical generator and can inhibit a weight balance and motion performance of a vehicle from being deteriorated and lowered.

REFERENCE SIGNS LIST

1vehicle driving apparatus1avehicle driving apparatus2internal combustion engine2aintake pipe2bexhaust pipe2cinternal combustion engine body2doil pan2eheat exchanger (auxiliary device)2xoutput shaft4drive motor4amotor casing4brotor4cstator4doutput shaft6generator (electrical generator)6a generator casing6brotor6cstator6dinput shaft8aelectric power conversion apparatus casing8binverter (electric power conversion apparatus)8cconverter (electric power conversion apparatus)8dcooling liquid chamber8ejunction box10reduction gear (speed reduction mechanism)11vehicle11amotor room11bbonnet11cbody side frame12drive shaft14radiator dedicated to internal combustion engine16radiator dedicated to electric power conversion apparatuses16ainflow pipe16boutflow pipe18oil cooler20lithium-ion battery24bus bar (first conductor)26bus bar (second conductor)28air cleaner30catalyzer