Hybrid vehicle

Abstract

The invention relates to a hybrid vehicle. In a hybrid vehicle, (a) an engine and a first electric motor are disposed so as to be rotatable about a first axis, (b) a second electric motor, a speed reduction mechanism, and a differential gear are disposed so as to be rotatable about a second axis parallel to the first axis, and (c) in the direction of the second axis, a differential gear is disposed so as to be rotatable about the second axis. A second motor, a first planetary gear device, a second planetary gear device, and a differential gear are arranged in this order from the first motor side toward the engine side, (d) a second rotor shaft is connected to a sun gear of the first planetary gear device, and a ring gear of the first planetary gear device is connected to a sun gear of the second planetary gear device. The carrier of the second planetary gear device is connected to the differential gear.

Description

TECHNICAL FIELD

[0001] The present application relates to a hybrid vehicle that is provided with an engine, a first electric motor that is rotationally driven by the engine, a second electric motor, a reduction mechanism that reduces power of the second electric motor, and a differential gear that transmits power from the reduction mechanism. BACKGROUND

[0002] A hybrid vehicle that is provided with an engine, a first electric motor that is rotationally driven by the engine, a second electric motor, a reduction mechanism that reduces power of the second electric motor, and a differential gear that transmits power from the reduction mechanism is known. For example, the hybrid vehicle described in Japanese Patent Application Publication No. 2022-79981 is such a hybrid vehicle. In the hybrid vehicle described in Japanese Patent Application Publication No. 2022-79981, (a) the engine and the first electric motor are respectively arranged so as to be able to rotate about a first axis, (b) the second electric motor, the reduction mechanism, and the differential gear are respectively arranged so as to be able to rotate about a second axis that is parallel to the first axis, (c) in the second axis direction, the second electric motor, the reduction mechanism, and the differential gear are arranged in this order from the first electric motor side toward the engine side. In addition, in the hybrid vehicle described in Japanese Patent Application Publication No. 2022-79981, a stepped pinion type planetary gear device is provided as the reduction mechanism. The "stepped pinion type planetary gear device" refers to a device in which a large-diameter pinion and a small-diameter pinion that are rotationally fixed to each other, a sun gear that meshes with the large-diameter pinion, and a ring gear that is fixed to a non-rotating member and that meshes with the small-diameter pinion are provided, and power is input from the sun gear to the large-diameter pinion and power is output from a carrier. The stepped pinion type planetary gear device is a reduction mechanism in which the reduction ratio is easily increased and the efficiency of power transmission is difficult to reduce.

[0003] However, the stepped pinion type planetary gear device is likely to suppress an increase in the length in the axis direction thereof, and on the other hand, the outer diameter with respect to the axis thereof is likely to increase. Therefore, in a case where the engine that protrudes in the radial direction with the first axis as the center and the stepped pinion type planetary gear device that protrudes in the radial direction with the second axis as the center are arranged at a position that overlaps in the first axis direction (= the same direction as the second axis direction), in order to arrange the engine and the stepped pinion type planetary gear device so as not to physically overlap, it can be necessary to increase the axial distance between the first axis and the second axis. When the axial distance between the first axis and the second axis increases, the volume of the entire engine that is arranged so as to be able to rotate about the first axis and the entire power train that is arranged so as to be able to rotate about the second axis increases. Due to this, for example, the aerodynamic characteristics of the vehicle deteriorate, or the degree of freedom of the vehicle design decreases. SUMMARY

[0004] The present application has been achieved in view of the above-described circumstances, and has an object to provide a hybrid vehicle capable of suppressing an increase in the overall size of each device of an engine and a power train.

[0005] The gist of the present application is a hybrid vehicle provided with an engine, a first electric motor that is rotationally driven by the engine, a second electric motor, a reduction mechanism that reduces the power of the second electric motor, and a differential gear that transmits the power from the reduction mechanism, (a) the engine and the first electric motor are each configured to be rotatable about a first axis, (b) the reduction mechanism includes a first planetary gear device and a second planetary gear device, (c) the second electric motor, the first planetary gear device, the second planetary gear device, and the differential gear are each configured to be rotatable about a second axis that is parallel to the first axis, (d) in the direction of the second axis, the second electric motor, the first planetary gear device, the second planetary gear device, and the differential gear are sequentially arranged from the first electric motor side toward the engine side, (e) the output shaft of the second electric motor is connected to the sun gear of the first planetary gear device, the ring gear of the first planetary gear device is connected to the sun gear of the second planetary gear device, and the carrier of the second planetary gear device is connected to the differential gear.

[0006] According to the present application, (a) the engine and the first electric motor are each configured to be rotatable about a first axis, (b) the reduction mechanism includes a first planetary gear device and a second planetary gear device, (c) the second electric motor, the first planetary gear device, the second planetary gear device, and the differential gear are each configured to be rotatable about a second axis parallel to the first axis, (d) the second electric motor, the first planetary gear device, the second planetary gear device, and the differential gear are arranged in this order from the first electric motor side toward the engine side in the second axis direction, (e) an output shaft of the second electric motor is connected to a sun gear of the first planetary gear device, a ring gear of the first planetary gear device is connected to a sun gear of the second planetary gear device, and a carrier of the second planetary gear device is connected to the differential gear. According to the above-described (e), the reduction ratio of the reduction mechanism including the first planetary gear device and the second planetary gear device is increased, and an increase in the outer diameter with respect to the second axis is suppressed. In this way, the increase in the outer diameter of each device of the powertrain arranged to be rotatable about the second axis and arranged in the second axis direction to protrude from the first electric motor side toward the engine side according to the above-described (d) is suppressed. Thus, the engine arranged to be rotatable about the first axis and each device of the powertrain arranged to be rotatable about the second axis parallel to the first axis can be arranged while suppressing an increase in the axial distance between the first axis and the second axis. That is, an increase in the volume of the entire engine and each device of the powertrain can be suppressed. BRIEF DESCRIPTION OF DRAWINGS

[0007] Features, advantages, and technical and industrial significance of exemplary embodiments of the present application will be described below with reference to the accompanying drawings, wherein the same reference numerals denote the same elements throughout the drawings, and wherein:

[0008] Figure 1 is a schematic configuration view of a hybrid vehicle of Embodiment 1 of the present application.

[0009] Figure 2 is a schematic configuration view of a hybrid vehicle of Embodiment 2 of the present application.

[0010] Figure 3 is a schematic configuration view of a hybrid vehicle of Embodiment 3 of the present application. DETAILED DESCRIPTION

[0011] Each embodiment of the present application will be described below in detail with reference to the accompanying drawings. Furthermore, when not specifically mentioned in each embodiment, the drawings are appropriately simplified or modified, and the dimensional ratios and shapes of each part are not necessarily accurately depicted.

[0012] [Embodiment 1]

[0013] Figure 1 is a schematic configuration view of a hybrid vehicle 10 (hereinafter, simply denoted as "vehicle 10") of Embodiment 1 of the present application. In Figure 1 , the upper and lower directions in the direction of the vertical line of the vehicle 10 and the left and right directions in the vehicle width direction are respectively indicated by arrows. Figure 1 is a view of a case where the front is observed from the rear of the vehicle 10.

[0014] The vehicle 10 is provided with an engine 12, a crankshaft 30, a damper 14, an input shaft 32, a power distribution mechanism 20, a first motor MG1, a countershaft 26, a second motor MG2, a reduction mechanism 42 including a first planetary gear device 42a and a second planetary gear device 42b, a differential gear 44, a pair of axles 48, and a pair of drive wheels 50. The reduction mechanism 42 reduces the power output from the second motor MG2 and outputs to the differential gear 44. The damper 14, the input shaft 32, the power distribution mechanism 20, the first motor MG1, the countershaft 26, the second motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are housed in a drive axle housing 16. In Figure 1 , each device shown in the drive axle housing 16 is shown while reflecting the relative positional relationship of their vertical and horizontal directions to each other.

[0015] The engine 12, the damper 14, the input shaft 32, the power distribution mechanism 20, and the first motor MG1 are respectively configured to be rotatable about a first axis line CL1.

[0016] The engine 12 is a publicly known internal combustion engine. The damper 14 is a publicly known device that absorbs variation generated by the power input from the crankshaft 30 of the engine 12 and outputs to the input shaft 32. Further, in the present specification, power, driving force, force (= power), and torque are synonymous without particular distinction.

[0017] The first motor MG1 and the second motor MG2 are publicly known structures that are so-called motor generators having a function as a motor and a function as a generator.

[0018] The power distribution mechanism 20 is, for example, a known power distribution mechanism constituted by a known planetary gear device of a single pinion type. In the planetary gear device constituting the power distribution mechanism 20, the first rotor shaft 34 that is a rotor shaft of the first electric motor MG1 is linked to the sun gear SO, the engine 12 is linked to the carrier CA0 via the input shaft 32 and the damper 14, and the reverse drive gear 22 is linked to the ring gear RO. The planetary gear device constituting the power distribution mechanism 20 corresponds to the "third planetary gear device" in the present application. The sun gear SO corresponds to the "sun gear of the third planetary gear device" in the present application. The carrier CA0 corresponds to the "carrier of the third planetary gear device" in the present application.

[0019] The power output from the engine 12 is mechanically distributed by the power distribution mechanism 20 to the first electric motor MG1 and the reverse drive gear 22 via the damper 14 and the input shaft 32. The first electric motor MG1 is rotationally driven by the power of the engine 12 distributed to the first electric motor MG1 by the power distribution mechanism 20. For example, the first electric motor MG1 generates power by the power of the engine 12 distributed to the first electric motor MG1. The power distribution mechanism 20 functions as an electrically controlled continuously variable transmission that controls the differential state of the power distribution mechanism 20 by controlling the operating state of the first electric motor MG1. The generated power by the first electric motor MG1 is used for charging of a battery not shown, or for driving the second electric motor MG2.

[0020] The second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, the differential gear 44, and the pair of axles 48 are configured to be rotatable about the second axis line CL2, respectively. The second axis line CL2 is parallel to the first axis line CL1. Since the first axis line CL1 is parallel to the second axis line CL2, the first axis line CL1 direction and the second axis line CL2 direction are the same direction. The second axis line CL2 passes directly below the engine 12. In the second axis line CL2 direction, the second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are disposed in this order from the first electric motor MG1 side toward the engine 12 side. In this way, in the second axis line CL2 direction (= the same direction as the first axis line CL1 direction), the engine 12, the damper 14, the power distribution mechanism 20, and the first electric motor MG1 are disposed in this order from one side toward the other side, and the second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are disposed in this order from the other side toward one side.

[0021] In the second axis CL2 direction, the first motor MG1 and the second motor MG2 are arranged at overlapping positions. That is, when viewed in a radial direction centered on the second axis CL2, the second motor MG2 is arranged at a position overlapping the first motor MG1. In the present embodiment, the second motor MG2 is arranged directly below the first motor MG1. In the second axis CL2 direction, the engine 12 and the second planetary gear device 42b and the differential gear 44 are arranged at overlapping positions. That is, when viewed in a radial direction centered on the second axis CL2, the second planetary gear device 42b and the differential gear 44 are arranged at positions overlapping the engine 12. In the present embodiment, the second planetary gear device 42b and the differential gear 44 are arranged directly below the engine 12. That is, in the second axis CL2 direction, the second planetary gear device 42b and the differential gear 44, which constitute part of the reduction mechanism 42, are arranged projecting directly below the engine 12.

[0022] The second rotor shaft 40, which is a rotor shaft of the second motor MG2, is connected to the sun gear S1 of the first planetary gear device 42a. The second rotor shaft 40 corresponds to the "output shaft of the second motor" in the present application. The sun gear S1 corresponds to the "sun gear of the first planetary gear device" in the present application. A non-rotating member (for example, the drive axle housing 16) is connected to the carrier CA1 of the first planetary gear device 42a. The ring gear R1 of the first planetary gear device 42a is connected to the sun gear S2 of the second planetary gear device 42b, and engages with the reverse driven gear 36 described later via the peripheral gear 38. The ring gear R1 corresponds to the "ring gear of the first planetary gear device" in the present application. The peripheral gear 38 is a gear provided to the outer peripheral portion of the ring gear R1. The sun gear S2 corresponds to the "sun gear of the second planetary gear device" in the present application. The differential housing, which is a housing portion of the differential gear 44, is connected to the carrier CA2 of the second planetary gear device 42b. The carrier CA2 corresponds to the "carrier of the second planetary gear device" in the present application. A non-rotating member (for example, the drive axle housing 16) is connected to the ring gear R2 of the second planetary gear device 42b. By connecting the second motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 in this way, the reduction ratios of the first planetary gear device 42a and the second planetary gear device 42b are increased, and the increase in the outer diameter with respect to the second axis CL2 is suppressed.

[0023] For example, the outer diameter D2 [mm] (<D1) of the first planetary gear device 42a is set to be smaller than the outer diameter D1 [mm] of the second motor MG2, the outer diameter D3 [mm] (<D2) of the second planetary gear device 42b is set to be smaller than the outer diameter D2 of the first planetary gear device 42a, and the outer diameter D4 [mm] (<D3) of the differential gear 44 is set to be smaller than the outer diameter D3 of the second planetary gear device 42b. In this way, the outer diameters of the devices of the power train configured to be able to rotate about the second axis CL2 gradually become smaller as they go from the first motor MG1 side toward the engine 12 side in the second axis CL2 direction.

[0024] The differential gear 44 is a well-known differential gear that receives an input power and appropriately allows a speed difference between a pair of drive wheels 50 via a pair of axles 48 and transmits equal driving torques to each other.

[0025] The countershaft 26 is a rotating member provided to be able to rotate about a third axis CL3. The third axis CL3 is parallel to the first axis CL1 and the second axis CL2. The countershaft 26 is provided with a reverse driven gear 36 in a non-rotatable manner. The reverse driven gear 36 is engaged with the reverse drive gear 22 and is engaged with the outer peripheral gear 38. In the power distribution mechanism 20, a first motor torque Tmg1 [N m] that is a reaction force torque of a negative torque generated by the first motor MG1 is input to the sun gear S0 with respect to an engine torque Te [N m] of a positive torque input to the gear carrier CA0. The first motor torque Tmg1 is an output torque of the first motor MG1. Thereby, the ring gear R0 of the power distribution mechanism 20 exhibits an engine direct torque Td [N m] of a positive torque in a positive rotation. In this way, a part of the engine torque Te is transmitted as the engine direct torque Td to the ring gear R1 of the first planetary gear device 42a via the outer peripheral gear 38. The engine torque Te corresponds to the "power of an engine" in the present application.

[0026] According to the present embodiment, (a) the engine 12 and the first electric motor MGl are configured to be rotatable about a first axis line CLl, respectively, (b) the reduction mechanism 42 includes a first planetary gear device 42a and a second planetary gear device 42b, (c) the second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are configured to be rotatable about a second axis line CL2 parallel to the first axis line CLl, respectively, (d) the second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are arranged in this order from the first electric motor MGl side toward the engine 12 side in the second axis line CL2 direction, (e) the second rotor shaft 40 is linked to a sun gear SI of the first planetary gear device 42a, a ring gear Rl of the first planetary gear device 42a is linked to a sun gear S2 of the second planetary gear device 42b, and a carrier CA2 of the second planetary gear device 42b is linked to the differential gear 44. According to the above-described (e), the reduction ratio of the reduction mechanism 42 including the first planetary gear device 42a and the second planetary gear device 42b is increased, and an increase in the outer diameter of the reduction mechanism 42 with respect to the second axis line CL2 is suppressed. In this way, the increase in the outer diameter of the reduction mechanism 42 with respect to the second axis line CL2 is suppressed, and the outer diameter of each device of the power train (particularly, the reduction mechanism 42) which is arranged to protrude from the first electric motor MGl side toward the engine 12 side in the second axis line CL2 direction and is configured to be rotatable about the second axis line CL2 is easily made small by the arrangement of the above-described (d). Thus, the engine 12 configured to be rotatable about the first axis line CLl and each device of the power train configured to be rotatable about the second axis line CL2 parallel to the first axis line CLl can be arranged while suppressing an increase in the axial distance between the first axis line CLl and the second axis line CL2. That is, an increase in the volume of the entire engine 12 and each device of the power train can be suppressed. For example, by suppressing an increase in the vertical direction of the entire engine 12 and each device of the power train, deterioration in the aerodynamic characteristics of the vehicle 10 is suppressed, and the degree of freedom in the appearance design which can be selected in the vehicle 10 is improved.

[0027] According to the present embodiment, the ring gear Rl of the first planetary gear device 42a is linked to the engine 12 in a manner such that the engine torque Te is transmitted to the ring gear Rl of the first planetary gear device 42a as the engine direct torque Td. In this way, at the ring gear Rl of the first planetary gear device 42a, a configuration in which the engine direct torque Td and the second electric motor torque Tmg2 [N m] are added together is obtained. Thus, for example, the engine 12 can be controlled to an efficient operating state, and controlled in a manner such that a required drive torque is transmitted to the pair of drive wheels 50. The second electric motor torque Tmg2 is the output torque of the second electric motor MG2, and corresponds to the "second electric motor power" in the present application.

[0028] According to the present embodiment, (a) the power distribution mechanism 20 is provided by a planetary gear device of a single pinion type configured to be rotatable about the first axis line CL1, (b) the engine 12 is linked to the carrier CA0 of the power distribution mechanism 20, and the first motor MG1 is linked to the sun gear S0 of the power distribution mechanism 20. Thereby, the power distribution mechanism 20 is configured to be rotatable about the same first axis line CL1 as the engine 12, and the rotational speed of the engine 12 is increased and transmitted to the first motor MG1. In this way, in the case where the engine 12 is linked to the carrier CA0 of the power distribution mechanism 20 and the first motor MG1 is linked to the sun gear S0 of the power distribution mechanism 20, the first motor MG1 is easily rotatable at a high rotational speed compared to the case where this is not so, and thus the power generation efficiency in the first motor MG1 is improved.

[0029] [Embodiment 2]

[0030] Figure 2 is a schematic configuration view of a hybrid vehicle 110 (hereinafter, simply denoted as "vehicle 110") of Embodiment 2 of the present application. In Figure 2 , the upper and lower directions in the direction of the vertical line of the vehicle 110 and the left and right directions are respectively indicated by arrows. Figure 2 is a view of the case where the front is observed from the rear of the vehicle 110. In Figure 2 , each device shown in the drive axle housing 16 is shown reflecting the relative positional relationship of their vertical and horizontal directions to each other.

[0031] The vehicle 110 is substantially the same configuration as the vehicle 10 of the aforementioned Embodiment 1, but differs mainly in that the power of the engine 12 is not transmitted to the pair of drive wheels 50. Therefore, the description will be made centering on the different parts from Embodiment 1, and the substantially common parts are denoted by the same reference numerals and the description is appropriately omitted.

[0032] The first motor MG1 in the present embodiment is a rotary electric machine having at least the function as a generator among the functions as a motor and as a generator, and is, for example, a so-called motor generator.

[0033] The vehicle 110 is provided with the speed-increasing planetary gear device 120 instead of the power distribution mechanism 20 of the vehicle 10 of Embodiment 1. In addition, the vehicle 110 is not provided with the countershaft 26, the reverse drive gear 22, the reverse driven gear 36, and the outer peripheral gear 38 provided in the vehicle 10 of Embodiment 1, respectively.

[0034] The step-up planetary gear device 120 is, for example, a single pinion type planetary gear device. The first motor MGl is linked to the sun gear S3 of the step-up planetary gear device 120. The engine 12 is linked to the carrier CA3 of the step-up planetary gear device 120 via the input shaft 32 and the damper 14. The non-rotating member (for example, the drive axle housing 16) is linked to the ring gear R3 of the step-up planetary gear device 120. In the step-up planetary gear device 120, the rotation of the engine 12 is input to the carrier CA3, and the rotational speed is stepped up and output from the sun gear S3 to the first motor MGl. The first motor MGl is rotationally driven by inputting the power of the engine 12 via the step-up planetary gear device 120. The step-up planetary gear device 120 corresponds to the "third planetary gear device" in the present application. The sun gear S3 corresponds to the "sun gear of the third planetary gear device" in the present application. The carrier CA3 corresponds to the "carrier of the third planetary gear device" in the present application.

[0035] According to the present embodiment, as with the aforementioned embodiment 1, (a) the engine 12 and the first motor MGl are configured to be able to rotate around the first axis line CLl, respectively, (b) the reduction mechanism 42 includes a first planetary gear device 42a and a second planetary gear device 42b, (c) the second motor MGl, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are configured to be able to rotate around the second axis line CL2 parallel to the first axis line CLl, respectively, (d) in the second axis line CL2 direction, the second motor MGl, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are sequentially arranged from the first motor MGl side toward the engine 12 side, (e) the second rotor shaft 40 is linked to the sun gear Sl of the first planetary gear device 42a, the ring gear Rl of the first planetary gear device 42a is linked to the sun gear S2 of the second planetary gear device 42b, and the carrier CA2 of the second planetary gear device 42b is linked to the differential gear 44. Thereby, the same effects as embodiment 1 based on these structures are exerted.

[0036] According to the present embodiment, (a) the step-up planetary gear device 120 is provided by a planetary gear device of a single pinion type configured to be rotatable about the first axis CL1, (b) the engine 12 is coupled to the carrier CA3 of the step-up planetary gear device 120, and the first motor MG1 is coupled to the sun gear S3 of the step-up planetary gear device 120. Thus, the step-up planetary gear device 120 is configured to be rotatable about the first axis CL1 same as the engine 12, and the rotational speed of the engine 12 is stepped up and transmitted to the first motor MG1. Thus, the first motor MG1 is easily rotated at a high rotational speed, thereby improving the power generation efficiency in the first motor MG1. Preferably, for example, in a case where the first motor MG1 is configured to efficiently generate power at a small diameter and a high rotational speed, the power generation efficiency in the first motor MG1 can be improved compared to a case where this is not so, and the increase in the axial distance between the first axis CL1 and the second axis CL2 is easily suppressed.

[0037] [Embodiment 3]

[0038] Figure 3 is a schematic configuration view of a hybrid vehicle 210 (hereinafter, simply referred to as "vehicle 210") of Embodiment 3 of the present application. In Figure 3 , the upper and lower directions in the direction of the vertical line of the vehicle 210 and the left and right directions are respectively indicated by arrows. Figure 3 is a view of the case where the front is observed from the rear of the vehicle 210. In Figure 3 , each device shown in the drive axle housing 16 is shown reflecting the relative positional relationship of their vertical and horizontal directions to each other.

[0039] The vehicle 210 is of substantially the same configuration as the vehicle 110 of the aforementioned Embodiment 2, but differs mainly in that the step-up planetary gear device 120 is not provided. Therefore, the description will be made centering on the parts different from Embodiment 2, and the substantially common parts are designated by the same reference numerals and the description is appropriately omitted.

[0040] The vehicle 210 does not have the step-up planetary gear device 120 of the vehicle 110 of Embodiment 2, and the input shaft 32 and the first rotor shaft 34 are engaged in a non-rotatable manner at the fitting portion F such as a spline fitting. In this way, the vehicle 210 is directly coupled in a manner that the engine 12 and the first motor MG1 become the same rotational speed. The first motor MG1 is rotationally driven by the power of the engine 12.

[0041] According to the present embodiment, as with the aforementioned Embodiment 1 and Embodiment 2, (a) the engine 12 and the first electric motor MGl are configured to be rotatable about a first axis line CLl, respectively, (b) the reduction mechanism 42 includes a first planetary gear device 42a and a second planetary gear device 42b, (c) the second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are configured to be rotatable about a second axis line CL2 parallel to the first axis line CLl, respectively, (d) in the second axis line CL2 direction, the second electric motor MG2, the first planetary gear device 42a, the second planetary gear device 42b, and the differential gear 44 are arranged in this order from the first electric motor MGl side toward the engine 12 side, (e) the second rotor shaft 40 is linked to a sun gear SI of the first planetary gear device 42a, a ring gear Rl of the first planetary gear device 42a is linked to a sun gear S2 of the second planetary gear device 42b, and a carrier CA2 of the second planetary gear device 42b is linked to the differential gear 44. Thereby, the same effects as Embodiment 1 and Embodiment 2 based on these structures are exerted.

[0042] According to the present embodiment, the engine 12 and the first electric motor MGl are directly linked in a manner such that they become the same rotational speed. In the case where the engine 12 and the first electric motor MGl are directly linked, as compared with the case where the engine 12 and the first electric motor MGl are not directly linked but linked via, for example, a step-up planetary gear device 120, it is possible to reduce the size in the first axis line CLl direction of the engine 12 and the first electric motor MGl configured to be rotatable about the first axis line CLl. It is preferable that, for example, in the case where the first electric motor MGl is configured to be able to generate power with a large diameter and at a low rotational speed with high efficiency, as compared with the case where this is not so, it is possible to reduce the size in the first axis line CLl direction of the engine 12 and the first electric motor MGl.

[0043] Further, the above is each of the embodiments of the present application, and the present application can be implemented in a manner applied with various changes and improvements based on the knowledge of those skilled in the art without departing from the gist thereof.

[0044] In the aforementioned Embodiments 1, 2, and 3, a manner in which the damper 14 is provided between the engine 12 and the first electric motor MGl is adopted, but the present application is not limited thereto. For example, the present application can also be applied to a manner in which the damper 14 is not provided between the engine 12 and the first electric motor MGl.

[0045] In the above-described embodiments 1, 2, 3, the second axis CL2 passes directly below the engine 12, but the application is not limited to this. For example, the application can also be applied to a case where the second axis CL2 is offset to either of the front and rear of the vehicle 10, 110, 210 with respect to the first axis CL1 and the second axis CL2 does not pass directly below the engine 12. Even in such a case, the reduction ratio of the reduction mechanism 42 including the first planetary gear device 42a and the second planetary gear device 42b is increased, and the increase in the outer diameter with respect to the second axis CL2 is suppressed. Thereby, the engine 12 configured to be able to rotate around the first axis CL1 and each device of the powertrain configured to be able to rotate around the second axis CL2 can be arranged while suppressing the increase in the axial distance between the first axis CL1 and the second axis CL2. That is, the increase in the volume of the entire engine 12 and each device of the powertrain can be suppressed.

Claims

1. A hybrid vehicle comprising an engine, a first electric motor driven by the engine, a second electric motor, a reduction mechanism for reducing the power of the second electric motor, and a differential gear for transmitting power from the reduction mechanism, characterized in that, The engine and the first electric motor are respectively configured to rotate about a first axis. The reduction mechanism includes a first planetary gear assembly and a second planetary gear assembly. The second electric motor, the first planetary gear assembly, the second planetary gear assembly, and the differential gear are each configured to rotate about a second axis parallel to the first axis. Along the second axial direction, the second electric motor, the first planetary gear assembly, the second planetary gear assembly, and the differential gear are arranged sequentially from the first electric motor side toward the engine side. The output shaft of the second motor is connected to the sun gear of the first planetary gear assembly, the ring gear of the first planetary gear assembly is connected to the sun gear of the second planetary gear assembly, and the gear carrier of the second planetary gear assembly is connected to the differential gear.

2. The hybrid vehicle according to claim 1, characterized in that, The connection is made in such a way that the power of the engine is transmitted to the ring gear of the first planetary gear unit as the engine direct torque.

3. The hybrid vehicle according to claim 1 or 2, characterized in that, The hybrid vehicle includes a third planetary gear assembly configured to rotate about the first axis. The engine is connected to the gear carrier of the third planetary gear unit, and the first electric motor is connected to the sun gear of the third planetary gear unit.

4. The hybrid vehicle according to claim 1, characterized in that, The engine and the first electric motor are directly connected at the same rotational speed.

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