Power transmission device

Abstract

To provide a power transmission device which performs torque vectoring without a rotating electric machine for the torque vectoring.SOLUTION: A power transmission device 10 of a vehicle with an engine 2, a first rotary electric machine 3, a differential mechanism 5, and a second rotary electric machine 4 comprises: a main power transmission path 51 which distributes and transfers at least one power of the engine 2 and the first rotary electric machine 3 through the differential mechanism 5 to a left drive shaft 11L and a right drive shaft 11R respectively; a power generation transmission path 54 which transfers power of the engine 2 to the second rotary electric machine 4; and an adjusting power transmission path 55 which is arranged separated from the main power transmission path 51 to transfer power of the second rotary electric machine 4 to the left drive shaft 11L or the right drive shaft 11R. The adjusting power transmission path 55 includes a first disengaging mechanism 41C which engages and disengages transmission of power of the second rotary electric machine 4. The power generation transmission path 54 includes a second disengaging mechanism 42G which engages and disengages transmission of power from the engine 2 to the second rotary electric machine 4.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a power transmission device for a vehicle equipped with a driving engine and a rotating electric machine, and a rotating electric machine for generating electricity. [Background technology]

[0002] Conventionally, there are known power transmission devices for vehicles equipped with an engine and a rotating electric machine (motor) for driving, and a rotating electric machine (generator) for generating electricity, which are capable of realizing a variety of driving modes. For example, Patent Document 1 discloses a transaxle device (power transmission device) that can switch between an EV mode in which the vehicle runs solely on the motor using battery charging power, a series mode in which the engine drives a generator to generate electricity and the vehicle runs solely on the motor, and a parallel mode in which the vehicle runs using both the engine and the motor. In Patent Document 1, the engine and motor as drive sources are connected in parallel via a differential device built into the power transmission device, and their driving force is distributed and transmitted to the left and right wheels via the differential device. In addition, a generator and a differential device are connected in parallel to the engine via the power transmission device, and the driving force of the engine is transmitted to the generator in addition to the left and right wheels. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-046204 Summary of the Invention [Problem to be solved by the invention]

[0004] Recently, attention has been focused on so-called torque vectoring, a technology that actively generates a difference in rotation speed between the left and right wheels by applying a driving force for adjusting the driving force distribution between the left and right wheels, separate from the driving force for driving the left and right wheels. Torque vectoring can adjust the yaw moment, stabilize the vehicle posture, and achieve desired cornering performance. However, in order to implement torque vectoring in a vehicle such as that disclosed in Patent Document 1, it is necessary to add a new motor that applies a driving force for adjusting the driving force distribution, which poses challenges in terms of cost reduction and space saving.

[0005] The present invention was conceived in consideration of the above-described problems, and has as one object to provide torque vectoring in a vehicle power transmission equipped with an engine and a rotating electric machine for drive, and a rotating electric machine for generating electricity, without the need to add a new rotating electric machine for torque vectoring. However, the present invention is not limited to this object. Another object of the present invention is to provide effects that cannot be obtained by conventional techniques, which are derived from the configurations described in the following detailed description of the invention. [Means for solving the problem]

[0006] The disclosed vehicle control device can be realized as the following disclosed aspects (application examples), which solve at least part of the above-mentioned problems. Each of the aspects from aspect 2 onwards is an aspect that can be selected as an additional option, and each of the aspects from aspect 2 onwards is an aspect that can be omitted. None of the aspects from aspect 2 onwards discloses an aspect or configuration that is essential to the present invention.

[0007] Aspect 1. The disclosed power transmission device is for a vehicle equipped with an engine, a first rotating electric machine, a differential mechanism interposed between a left drive shaft and a right drive shaft, and a second rotating electric machine that generates electricity using power from the engine. The power transmission device includes a main power transmission path that distributes and transmits power from at least one of the engine and the first rotating electric machine to each of the left drive shaft and the right drive shaft via the differential mechanism, a generator power transmission path that transmits power from the engine to the second rotating electric machine, and an adjustment power transmission path that is separate from the main power transmission path and transmits power from the second rotating electric machine to the left drive shaft or the right drive shaft. The power transmission device includes a first connection / disconnection mechanism that is provided on the adjustment power transmission path and that connects and disconnects the transmission of power from the second rotating electric machine, and a second connection / disconnection mechanism that is provided on the generator power transmission path and that connects and disconnects the transmission of power from the engine to the second rotating electric machine.

[0008] Aspect 2. In an aspect including the aspect 1 described above, when both the generation of power by the second rotating electric machine via the power generation power transmission path and the transmission of power from the second rotating electric machine via the adjustment power transmission path are not required, it is preferable that both the first disconnecting mechanism and the second disconnecting mechanism are in a disconnected state.

[0009] Aspect 3. In any aspect including Aspect 1 described above, it is preferable that the main power transmission path be provided with a first power transmission path that transmits the power of the engine and a second power transmission path that transmits the power of the first rotating electric machine separately. In this case, it is preferable that a third connection / disconnection mechanism that connects and disconnects the transmission of power from the engine to the differential mechanism be provided on the first power transmission path.

[0010] Aspect 4. In an aspect including the above aspect 3, when the vehicle runs using the power of the first rotating electric machine, it is preferable that the first connecting / disconnecting mechanism is in an engaged state, the second connecting / disconnecting mechanism is in a disconnected state, and the third connecting / disconnecting mechanism is in a disconnected state.

[0011] Aspect 5. In an aspect including Aspect 3 above, when the vehicle is traveling using the power of the engine, it is preferable that the first connecting / disconnecting mechanism is in an engaged state, the second connecting / disconnecting mechanism is in a disengaged state, and the third connecting / disconnecting mechanism is in an engaged state.

[0012] Aspect 6. In an aspect including aspect 3 above, when the vehicle runs on the power of the first rotating electric machine and requires power generation by the second rotating electric machine via the generated power transmission path, it is preferable that the first connecting / disconnecting mechanism is in a disconnected state, the second connecting / disconnecting mechanism is in an engaged state, and the third connecting / disconnecting mechanism is in a disconnected state.

[0013] Aspect 7. In an aspect including the above aspect 3, when the vehicle requires both power generation using power from the engine and power transmission from the second rotating electric machine via the adjusted power transmission path, it is preferable that the first connecting / disconnecting mechanism is engaged, the second connecting / disconnecting mechanism is disengaged, and the third connecting / disconnecting mechanism is engaged. In this case, it is preferable that the vehicle runs using power from the engine, and the first rotating electric machine generates power using part of the power of the engine. [Effects of the Invention]

[0014] According to the disclosed power transmission device, torque vectoring can be performed without adding a new rotating electric machine for torque vectoring. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a top view illustrating a configuration of a front part of a vehicle equipped with a power transmission device according to an embodiment. [Figure 2] FIG. 2 is a skeleton diagram showing the power train of FIG. 1. [Figure 3] FIG. 2 is a skeleton diagram showing the powertrain of FIG. 1, illustrating the operation of the power transmission device in an EV mode. [Figure 4]FIG. 2 is a skeleton diagram showing the powertrain of FIG. 1, illustrating the operation of the power transmission device in a parallel mode. [Figure 5] FIG. 2 is a skeleton diagram showing the powertrain of FIG. 1, illustrating the operation of the power transmission device in a series mode. [Figure 6] FIG. 2 is a skeleton diagram showing the powertrain of FIG. 1, illustrating the operation of the power transmission device in a pseudo series mode. DETAILED DESCRIPTION OF THE INVENTION

[0016] A power transmission device according to an embodiment will be described with reference to the drawings. The embodiment described below is merely an example, and is not intended to exclude various modifications or applications of techniques not explicitly described in the embodiment. The configurations of the present embodiment can be modified in various ways without departing from the spirit of the invention. Furthermore, they can be selected or combined as needed.

[0017] In the following description, the forward direction of the vehicle is referred to as the forward direction (front of the vehicle), and the opposite direction is referred to as the rearward direction (rear of the vehicle). The forward direction of the vehicle is referred to as the forward direction when the vehicle is moving forward, and as the rearward direction when the vehicle is moving backward. Furthermore, left and right are defined based on the state in which the vehicle is facing forward. The left and right directions are perpendicular to the front-to-rear direction of the vehicle.

[0018] [1. Overall structure] FIG. 1 is a schematic diagram showing the front of a vehicle 1 to which a power transmission device 10 of this embodiment is applied. The vehicle 1 is a hybrid vehicle (HEV, Hybrid Electric Vehicle) or a plug-in hybrid vehicle (PHEV, Plug-in Hybrid Electric Vehicle) equipped with both an engine 2 and a motor 3 (first rotating electric machine) as drive sources. A plug-in hybrid vehicle is a hybrid vehicle that can externally charge a battery 7 (described below) or externally supply power from the battery 7. A plug-in hybrid vehicle is provided with a charging port (inlet) for inserting a charging cable that supplies power from external charging equipment and a receptacle (outlet) for external power supply.

[0019] As shown in FIG. 1, in addition to the engine 2 and motor 3, the vehicle 1 is also provided with a generator 4 (second rotating electric machine) for generating electricity and a differential mechanism 5. The engine 2, motor 3, and generator 4 are each connected to a power transmission device 10, and the differential mechanism 5 is built into the power transmission device 10. An axle 6 of a driving wheel W is also connected to the power transmission device 10. The power transmission device 10 is interposed between a left axle 6L of a left driving wheel WL and a right axle 6R of a right driving wheel WR. Hereinafter, the engine 2, motor 3, generator 4, differential mechanism 5, and power transmission device 10 will be collectively referred to as a power train PT.

[0020] The engine 2 is an internal combustion engine (gasoline engine, diesel engine) that uses gasoline or diesel as fuel. The engine 2 burns a mixture of fuel and air in a combustion chamber to output driving force (power, torque) for running the vehicle 1 and driving force for the generator 4 to generate electricity. The operating state of the engine 2 is controlled by a control device (not shown). For example, as shown in the figure, the engine 2 may be fixed to the right side of the power transmission device 10, with its crankshaft 2a disposed parallel to the axle 6 (aligned with the vehicle width direction of the vehicle 1).

[0021] The motor 3 is a motor-generator that functions both as an electric motor and as a generator. During power running, the motor 3 acts as an electric motor, receiving electric power from the battery 7 and electric power generated by the generator 4, and outputs driving force for running the vehicle 1. During regeneration, the motor 3 acts as a generator, charging the generated regenerated electric power into the battery 7. For example, as shown in the figure, the motor 3 may be fixed to the left side surface of the power transmission device 10, and its rotation shaft 3a may be arranged parallel to the axle 6.

[0022] The battery 7 is, for example, a lithium-ion secondary battery or a nickel-metal hydride secondary battery, and is a secondary battery capable of supplying a high-voltage direct current of several hundred volts. The motor 3 and battery 7 are electrically connected via a motor inverter (not shown). The motor inverter is a converter (DC-AC inverter) that converts between the power of a direct current circuit on the battery 7 side (DC power) and the power of an alternating current circuit on the motor 3 side (AC power), and is controlled by a control device (not shown).

[0023] The generator 4 is a motor-generator that functions both as an electric motor and as a generator, similar to the motor 3. The generator 4 functions as a conventional generator that charges the battery 7 with electric power generated by the driving force of the engine 2. The generator 4 also has a function of outputting driving force for adjusting the distribution of driving force between the left driving wheel WL and the right driving wheel WR (performing so-called torque vectoring).

[0024] That is, the vehicle 1 of this embodiment utilizes the generator 4 provided in a conventional hybrid vehicle or a plug-in hybrid vehicle as a motor for torque vectoring. The power transmission device 10 has a configuration that enables torque vectoring by the generator 4.

[0025] The generator 4 and the battery 7 are electrically connected via a generator inverter (not shown). The generator inverter is a converter (DC-AC inverter) similar to the motor inverter, and is controlled by a control device (not shown). For example, as shown in the figure, the generator 4 may be fixed to the left side surface of the power transmission device 10, and its rotation shaft 4a may be arranged parallel to the axle 6.

[0026] The vehicle 1 may be provided with a control device 8 that controls a connection / disconnection mechanism 41 and a switching mechanism 42 (described later) of the power transmission device 10. The control device 8 is, for example, an electronic control device configured as an LSI device or an embedded electronic device that integrates a microprocessor, ROM, RAM, etc. The control device 8 may be, for example, an integrated control device (Electronic Control Unit, upper control device) that controls various devices mounted on the vehicle. Alternatively, the control device 8 may be a lower-level control device than the integrated control device, provided separately from the control devices that control the engine 2, motor inverter, and generator inverter, and may control the connection / disconnection mechanism 41 and the switching mechanism 42 based on information received from the integrated control device.

[0027] The vehicle 1 may also be provided with a sensor 9 that detects information for determining whether torque vectoring is necessary. Torque vectoring is mainly performed when the vehicle 1 is turning, and therefore, in order to determine whether torque vectoring is necessary, information that can determine whether the vehicle 1 is turning is required. Torque vectoring can also be performed to stabilize the attitude of the vehicle 1, and therefore, the information for determining whether torque vectoring is necessary may include information that can determine whether the vehicle 1 is in a situation where its attitude is likely to become unstable. Examples of information for determining whether torque vectoring is necessary include the speed and steering angle of the vehicle 1. Examples of the sensor 9 include a vehicle speed sensor that detects the vehicle speed and a steering sensor that detects the steering angle.

[0028] The information detected by the sensor 9 may be transmitted to the control device 8. For example, when the vehicle speed is equal to or greater than a predetermined vehicle speed and the steering angle is equal to or greater than a predetermined angle, the control device 8 may determine that the vehicle is cornering and that torque vectoring is required. Note that the information detected by the sensor 9 may be transmitted to an integrated control device, which may then determine whether torque vectoring is required, and transmit the result of this determination to the control device 8.

[0029] In this embodiment, an example is shown in which the front wheels are driven as drive wheels W by a powertrain PT provided at the front of the vehicle 1, but the drive wheels W do not have to be the front wheels, and the powertrain PT does not have to be provided at the front of the vehicle 1. For example, the vehicle 1 may be one in which the powertrain PT is provided at the rear of the vehicle 1 to drive rear wheels (not shown). The vehicle 1 may be one in which the powertrain PT is provided at both the front and rear of the vehicle 1 to drive both the front and rear wheels.

[0030] [2. Power transmission device] 2 is a skeleton diagram of a powertrain PT including a power transmission device 10 of this embodiment. As described above, the vehicle 1 of this embodiment utilizes the generator 4 as a motor for torque vectoring, and the power transmission device 10 enables torque vectoring by the generator 4. The power transmission device 10 is provided with a main path 51 (main power transmission path, see the thick dashed line in FIG. 2), a power generation path 54 (power generation power transmission path, see the thick dotted line in FIG. 2), and an adjustment path 55 (adjustment power transmission path, see the thick dashed line in FIG. 2).

[0031] The main path 51 is a power transmission path that distributes and transmits the driving force of at least one of the engine 2 and the motor 3 to each of the left axle 6L and the right axle 6R via the differential mechanism 5. The power generation path 54 is a power transmission path that transmits the driving force of the engine 2 to the generator 4. The adjustment path 55 is provided separately from the main path 51 and is a power transmission path that transmits the driving force of the generator 4 to the left axle 6L or the right axle 6R.

[0032] The power transmission device 10 is provided with, for example, eight shafts 11 to 18 arranged parallel to one another as elements for forming the three types of power transmission paths 51, 54, and 55. Hereinafter, the rotating shaft connected to the axle 6 will be referred to as the drive shaft 11. In this embodiment, the drive shaft 11 is connected coaxially with the axle 6. The left drive shaft 11L is connected to the left axle 6L, and the right drive shaft 11R is connected to the right axle 6R. In addition, the rotating shafts connected coaxially with the crankshaft 2a, the rotating shaft 3a of the motor 3, and the rotating shaft 4a of the generator 4 will be referred to as the engine shaft 12, the motor shaft 13, and the generator shaft 14, respectively.

[0033] Of the rotating shafts arranged on the power transmission path (first path 52 described later) between the engine shaft 12 and the drive shaft 11, the rotating shaft located on the upstream side of the power transmission path is referred to as the upstream first countershaft 15, and the rotating shaft located on the downstream side is referred to as the downstream first countershaft 16. Furthermore, the rotating shaft arranged on the power transmission path (second path 53 described later) between the motor shaft 13 and the drive shaft 11 is referred to as the second countershaft 17. The rotating shaft arranged on the adjustment path 55 between the generator shaft 14 and the drive shaft 11 is referred to as the third countershaft 18. In this embodiment, the third countershaft 18 is arranged between the generator shaft 14 and the left drive shaft 11L. In other words, the adjustment path 55 in this embodiment transmits the driving force of the generator 4 to the left drive shaft 11L (left axle 6L).

[0034] Both ends of each of the eight shafts 11 to 18 are supported by a casing 10C of the power transmission device 10 via bearings (not shown). Openings are formed in the side surfaces of the casing 10C located above each of the drive shaft 11, engine shaft 12, motor shaft 13, and generator shaft 14, and these shafts 11 to 14 are connected to the axle 6, crankshaft 2a, rotating shaft 3a, and rotating shaft 4a located outside the casing 10C, respectively.

[0035] The differential mechanism 5 is a differential mechanism in which a differential gear supported by a container-shaped differential case 5c is interposed coaxially between the left drive shaft 11L and the right drive shaft 11R. A left side gear 5a fixed to the left drive shaft 11L, a right side gear 5b fixed to the right drive shaft 11R, and a differential pinion gear 5p pivotally supported by the differential case 5c are housed in a meshed state inside the differential case 5c.

[0036] The differential case 5c is provided with a ring gear 5r that is connected to the differential case 5c so as not to rotate relative to the differential case 5c. The rotation axes of the left side gear 5a and the right side gear 5b are arranged on the same straight line, and the rotation axis of the differential pinion gear 5p is arranged perpendicular to this. The left side gear 5a, the right side gear 5b, and the differential case 5c can transmit power to each other, and their respective structures (position, shape, number of teeth) are set so that the rotational speeds on the nomographic diagram are arranged linearly in this order.

[0037] The three types of power transmission paths 51, 54, and 55 are described in detail below. In the following description, a "fixed gear" refers to a gear that is integral with a shaft and rotates synchronously with (non-rotatable relative to) the shaft. Also, an "idling gear" refers to a gear that is pivotally supported so as to be rotatable relative to the shaft.

[0038] The main path 51 is a path that distributes and transmits the driving force of at least one of the engine 2 and the motor 3 to the left drive shaft 11L and the right drive shaft 11R via the differential mechanism 5. In this embodiment, the main path 51 is provided separately from a first path 52 (first power transmission path, see thin dashed line in FIG. 2) that transmits the driving force of the engine 2 and a second path 53 (second power transmission path, see thin dashed line in FIG. 2) that transmits the driving force of the motor 3.

[0039] That is, in the power transmission device 10 of this embodiment, the engine 2 and the motor 3 are connected in parallel to the differential mechanism 5 (drive shaft 11) via the first path 52 and the second path 53. Hereinafter, the driving force transmitted from each of the engine 2 and the motor 3 to the drive shaft 11 via the differential mechanism 5 will be referred to as the traveling driving force.

[0040] The first path 52 is a power transmission path related to power transmission from the engine 2 to the differential mechanism 5, and is responsible for transmitting driving force when the engine 2 is operating. The engine shaft 12, the upstream first countershaft 15, and the downstream first countershaft 16 are provided on the first path 52, and a connection / disconnection mechanism 41 (third connection / disconnection mechanism) that connects and disconnects the power transmission is interposed midway along the first path 52.

[0041] A fixed gear 12A for driving is provided on the engine shaft 12. An upstream fixed gear 15Au and a downstream fixed gear 15Ad are provided on the upstream first countershaft 15, which are constantly meshed with the fixed gear 12A of the engine shaft 12. An idler gear 16Au, which is constantly meshed with the downstream fixed gear 15Ad of the upstream first countershaft 15, a connecting / disconnecting mechanism 41, and a fixed gear 16Ad are provided on the downstream first countershaft 16. The fixed gear 16Ad is constantly meshed with a ring gear 5r of the differential mechanism 5.

[0042] The connecting / disconnecting mechanism 41 is, for example, a dog clutch, and includes a dog gear 41d, a hub 41h, and a sleeve 41s. The dog gear 41d is connected to the idler gear 16Au of the downstream first countershaft 16 so as to be non-rotatable relative to the downstream first countershaft 16. The hub 41h is provided integrally with the downstream first countershaft 16 and is non-rotatable relative to the downstream first countershaft 16. The sleeve 41s is non-rotatable relative to the hub 41h (downstream first countershaft 16) and is connected to the downstream first countershaft 16 so as to be slidable in the axial direction.

[0043] The sleeve 41s has an annular shape that can be fitted onto the hub 41h, and is provided with spline teeth (not shown) on its radially inner side that engage with the dog teeth of the dog gear 41d. The spline teeth engage with the dog teeth, thereby engaging the sleeve 41s with the dog gear 41d. An actuator (not shown) is controlled by the control device 8, causing the sleeve 41s to move leftward from a neutral position in the drawing and engage (mesh) with the dog gear 41d. Hereinafter, the state in which the sleeve 41s engages with the dog gear 41d will be referred to as the "engaged state," and the state in which the sleeve 41s does not engage with the dog gear 41d will be referred to as the "disengaged state."

[0044] The second path 53 is a power transmission path related to power transmission from the motor 3 to the differential mechanism 5, and is responsible for transmitting driving force when the motor 3 is in power running. When the motor 3 is in regeneration mode, part of the power due to the inertial rotation of the drive wheels W and part of the driving force of the engine 2 are transmitted to the motor 3 via the second path 53. Therefore, the second path 53 can also be a path related to power transmission from the differential mechanism 5 to the motor 3.

[0045] The motor shaft 13 and the second counter shaft 17 are provided on the second path 53. A fixed gear 13B is provided on the motor shaft 13. The second counter shaft 17 is provided with an upstream fixed gear 17Bu that is constantly meshed with the fixed gear 13B of the motor shaft 13, and a downstream fixed gear 17Bd. The downstream fixed gear 17Bd is constantly meshed with the ring gear 5r of the differential mechanism 5.

[0046] The power generation path 54 is a path for transmitting power from the engine 2 to the generator 4, and is responsible for transmitting power when the engine 2 is operating. The engine shaft 12 and the generator shaft 14 are provided on the power generation path 54, and a power generation path disconnection mechanism 42G (second disconnection mechanism) for connecting and disconnecting the power transmission is interposed midway on the power generation path 54.

[0047] A fixed power generation gear 12G is provided on the engine shaft 12. As shown in the figure, the fixed power generation gear 12G may be provided to the left of the fixed drive gear 12A in the figure (toward the generator 4). The generator shaft 14 is provided with an idling gear 14G that is constantly meshed with the fixed power generation gear 12G of the engine shaft 12, and a power generation path disconnecting mechanism 42G. The power generation path disconnecting mechanism 42G will be described in detail later.

[0048] The adjustment path 55 is a path related to power transmission from the generator 4 to the left drive shaft 11L or the right drive shaft 11R, and is responsible for transmitting power when the generator 4 is operating. In this embodiment, the adjustment path 55 is responsible for power transmission from the generator 4 to the left drive shaft 11L, transmitting the driving force of the generator 4 to the left drive shaft 11L. The driving force transmitted from the generator 4 to the left drive shaft 11L is input to the differential mechanism 5, and a driving force with the sign of the driving force reversed is transmitted to the right drive shaft 11R. As a result, driving forces for adjusting the driving force distribution between the left drive wheel WL and the right drive wheel WR are applied to both the left drive shaft 11L and the right drive shaft 11R. Hereinafter, the driving force transmitted to the drive shaft 11 via the adjustment path 55 is referred to as adjusted driving force.

[0049] The generator shaft 14, the third countershaft 18, and the left drive shaft 11L are provided on the adjustment path 55, and an adjustment path disconnection mechanism 42C (first connection / disconnection mechanism) that connects and disconnects power transmission therebetween is provided midway on the adjustment path 55. The generator shaft 14 is provided with an idling gear 14C and the adjustment path disconnection mechanism 42C. As shown in the figure, the idling gear 14C of the adjustment path 55 may be provided to the left of the idling gear 14G of the power generation path 54 in the figure (toward the generator 4). The third countershaft 18 is provided with an upstream fixed gear 18Cu that is constantly meshed with the idling gear 14C of the generator shaft 14, and a downstream fixed gear 18Cd. The left drive shaft 11L is provided with a fixed gear 11C that is constantly meshed with the downstream fixed gear 18Cd of the third countershaft 18.

[0050] The power generation path disconnection mechanism 42G is, for example, a dog clutch and has a power generation side dog gear 42g, a hub 42h, and a sleeve 42s. Similarly, the adjustment path disconnection mechanism 42C is, for example, a dog clutch and has an adjustment side dog gear 42c, a hub 42h, and a sleeve 42s. In this embodiment, the hub 42h and sleeve 42s of the power generation path disconnection mechanism 42G and the hub 42h and sleeve 42s of the adjustment path disconnection mechanism 42C are identical (common), as shown in the figure. The power transmission device 10 is provided with a switching mechanism 42 that functions as both the power generation path disconnection mechanism 42G and the adjustment path disconnection mechanism 42C. As shown in the figure, the switching mechanism 42 is interposed between the idler gear 14G of the power generation path 54 and the idler gear 14C of the adjustment path 55.

[0051] The generator-side dog gear 42g is connected to the idler gear 14G on the generator path 54 so as to be non-rotatable relative to the generator path 54. The adjustment-side dog gear 42c is connected to the idler gear 14C on the adjustment path 55 so as to be non-rotatable relative to the generator path 14. The hub 42h is provided integrally with the generator shaft 14 and is non-rotatable relative to the generator shaft 14. The sleeve 42s is non-rotatable relative to the hub 42h (generator shaft 14) and is connected to the generator shaft 14 so as to be slidable in the axial direction.

[0052] The sleeve 42s has an annular shape that can be fitted onto the hub 42h, and its radially inner side is provided with spline teeth (not shown) that engage with the dog teeth of the dog gears 42g, 42c. The sleeve 42s can move to both the left and right from a neutral position in the drawing by an actuator (not shown) being controlled by the control device 8. The engagement of the spline teeth with the dog teeth engages the sleeve 42s with the generator-side dog gear 42g or the adjustment-side dog gear 42c.

[0053] Specifically, the sleeve 42s moves from the neutral position to the left in the figure, thereby engaging (meshing) with the adjustment-side dog gear 42c. This causes the adjustment path disconnection mechanism 42C to enter an engaged state. At this time, the power generation path disconnection mechanism 42G enters a disconnected state. Hereinafter, the state in which the sleeve 42s moves to the left, the adjustment path disconnection mechanism 42C enters an engaged state, and the power generation path disconnection mechanism 42G enters a disconnected state will be referred to as the "first state."

[0054] Furthermore, the sleeve 42s moves from the neutral position to the right in the figure, thereby engaging (meshing) with the power generation side dog gear 42g. This causes the power generation path disconnection mechanism 42G to enter an engaged state. At this time, the adjustment path disconnection mechanism 42C enters a disconnected state. Hereinafter, the state in which the sleeve 42s moves to the right, the power generation path disconnection mechanism 42G enters an engaged state, and the adjustment path disconnection mechanism 42C enters a disconnected state will be referred to as the "second state."

[0055] When the sleeve 42s is in the neutral position, the sleeve 42s is not engaged with either the generator-side dog gear 42g or the adjustment-side dog gear 42c, and therefore both the adjustment path disconnection mechanism 42C and the power generation path disconnection mechanism 42G are in a disconnected state. Hereinafter, the state in which both the adjustment path disconnection mechanism 42C and the power generation path disconnection mechanism 42G are in a disconnected state will be referred to as the "neutral state." In the switching mechanism 42 of this embodiment, the first state, the second state, and the neutral state are alternatively selected.

[0056] [3. Effect] 3 to 6, the operation of the above-described power transmission device 10 will be described. In the power transmission device 10, the states of the connection / disconnection mechanism 41 and the switching mechanism 42, the operating state of the engine 2, the driving state of the motor 3, and the driving state of the generator 4 are switched to realize the following four types of driving modes. EV mode Parallel mode Series Mode Pseudo-series mode

[0057] [3-1.EV Mode] The EV mode is a driving mode in which the vehicle 1 runs solely on the driving force of the motor 3 using the charging power of the battery 7. The EV mode is selected, for example, when the driving load and vehicle speed are low or when the charging level of the battery 7 is high.

[0058] In the EV mode, the motor 3 is put into a power running state, whereby the driving force of the motor 3 is transmitted to the differential mechanism 5 via the second path 53 of the main path 51, as shown by the dotted arrows in Figure 3, and then distributed by the differential mechanism 5 to the left drive shaft 11L and the right drive shaft 11R as driving force for traveling.

[0059] In the EV mode, the switching mechanism 42 is set to the first state as shown in Fig. 3. That is, the adjustment path connecting / disconnecting mechanism 42C is set to the engaged state, and the power generation path connecting / disconnecting mechanism 42G is set to the disconnected state. Furthermore, by appropriately switching the generator 4 between the powering state and the regenerative state, torque vectoring is achieved while traveling in the EV mode.

[0060] Specifically, when the generator 4 is put into a powering state, the powering driving force of the generator 4 is transmitted to the left drive shaft 11L as a positive adjusted driving force (an adjusted driving force in the same direction as the traveling driving force, for example, 10 [N]) via the adjustment path 55, as shown by the outline arrow in FIG. 3 . As a result, a driving force obtained by adding the positive adjusted driving force to the traveling driving force is transmitted to the left drive shaft 11L. Meanwhile, the positive adjusted driving force transmitted to the left drive shaft 11L is input to the left side gear 5a and adjusted by the differential mechanism 5, so that a negative adjusted driving force (an adjusted driving force in the opposite direction to the traveling driving force, for example, −10 [N]) obtained by reversing the positive adjusted driving force is transmitted to the right drive shaft 11R. As a result, a driving force obtained by adding the negative adjusted driving force to the traveling driving force (a driving force obtained by subtracting the absolute value of the adjusted driving force from the traveling driving force) is transmitted to the right drive shaft 11R.

[0061] Conversely, when the generator 4 is in a regenerative state, the regenerative driving force of the generator 4 is transmitted to the left drive shaft 11L via the adjustment path 55 as a negative adjusted driving force (for example, -10 [N]), as shown by the white arrow in FIG. 3. As a result, a driving force obtained by adding the negative adjusted driving force to the traveling driving force is transmitted to the left drive shaft 11L. On the other hand, the negative adjusted driving force transmitted to the left drive shaft 11L is adjusted by the differential mechanism 5, and a positive adjusted driving force, which is the opposite of the negative adjusted driving force, is transmitted to the right drive shaft 11R. As a result, a driving force obtained by adding the positive adjusted driving force to the traveling driving force is transmitted to the right drive shaft 11R.

[0062] In this way, in the power transmission device 10, the driving force (power driving force, regenerative driving force) of the generator 4 is transmitted via the adjustment path 55, and an adjusted driving force is applied to each of the left drive shaft 11L and the right drive shaft 11R. This actively creates a rotation speed difference between the left drive wheel WL and the right drive wheel WR, thereby achieving torque vectoring.

[0063] In the EV mode, the engine 2 is stopped and the connection / disconnection mechanism 41 is disconnected. Furthermore, the switching mechanism 42 is in the first state, so the power generation path connection / disconnection mechanism 42G is disconnected. In this way, the engine 2 is disconnected from both the generator 4 and the differential mechanism 5, thereby suppressing unnecessary power loss within the power transmission device 10.

[0064] In the EV mode, when torque vectoring is not required, the generator 4 may be controlled to rotate along with the vehicle (0[N] control). Alternatively, when torque vectoring is not required in the EV mode, the switching mechanism 42 may be controlled to be in a neutral state. As described above, the EV mode is selected when the charge level of the battery 7 is high, and therefore power generation by the generator 4 using power from the engine 2 is not required. In this way, when both power generation by the generator 4 via the power generation path 54 and torque vectoring are not required, the switching mechanism 42 is placed in a neutral state, thereby eliminating the need for the 0[N] control of the generator 4 described above and reducing power consumption by the generator 4.

[0065] [3-2. Parallel Mode] The parallel mode is a driving mode in which the vehicle 1 runs using at least the driving force of the engine 2, and as needed, the driving force of the motor 3 is used to assist the vehicle 1 in running (the vehicle runs using both the engine 2 and the motor 3). The parallel mode is selected, for example, when the running load and vehicle speed are high.

[0066] In the parallel mode, as shown in FIG. 4, the connecting / disconnecting mechanism 41 is engaged and the engine 2 is operating. As a result, the driving force of the engine 2 is transmitted to the differential mechanism 5 via a first path 52 of the main path 51, as indicated by the arrows with thick dots in FIG. 4. In addition, the motor 3 is set to a power running state as necessary. As a result, the driving force of the motor 3 is transmitted to the differential mechanism 5 via a second path 53 of the main path 51, as indicated by the arrows with light dots in FIG. 4, and is added to the driving force of the engine 2. The driving force transmitted to the differential mechanism 5 is distributed and transmitted by the differential mechanism 5 to each of the left drive shaft 11L and the right drive shaft 11R as traveling driving force.

[0067] In parallel mode, the switching mechanism 42 is set to the first state as shown in FIG. 4. That is, the adjustment path connection / disconnection mechanism 42C is set to the engaged state, and the power generation path connection / disconnection mechanism 42G is set to the disconnected state. Furthermore, torque vectoring during traveling in parallel mode is achieved by appropriately switching the generator 4 between the power generation state and the regeneration state. In parallel mode, as in EV mode, torque vectoring is achieved by transmitting the driving force of the generator 4 to the drive shaft 11 as adjusted driving force via the adjustment path 55, as shown by the white arrow in FIG. 4.

[0068] As in the EV mode, in the parallel mode, when torque vectoring is not required, the generator 4 may be controlled to 0 [N]. Alternatively, when torque vectoring is not required, the switching mechanism 42 may be controlled to be in a neutral state.

[0069] [3-3. Series Mode] The series mode is a driving mode in which the vehicle 1 runs on the driving force of only the motor 3 while the engine 2 drives the generator 4 to generate electricity. The series mode is selected, for example, when the driving load and vehicle speed are medium or when the charge level of the battery 7 is low. In other words, the series mode is a driving mode that is selected when it is required that the vehicle 1 runs on the driving force of only the motor 3 and when it is required that the generator 4 generate electricity using the engine 2.

[0070] In the series mode, the motor 3 is put into a powering state, whereby the driving force of the motor 3 is transmitted to the differential mechanism 5 via the second path 53 of the main path 51, as shown by the dotted arrows in Figure 5, and then distributed by the differential mechanism 5 to the left drive shaft 11L and the right drive shaft 11R as a driving force for traveling.

[0071] In the series mode, as shown in Fig. 5, the connection / disconnection mechanism 41 is in the disconnected state, and the switching mechanism 42 is in the second state. That is, the power generation path connection / disconnection mechanism 42G is in the engaged state, and the adjustment path connection / disconnection mechanism 42C is in the disconnected state. In addition, the engine 2 is in the operating state, and the generator 4 is in the regenerative (power generation) state. As a result, the connection between the engine 2 and the differential mechanism 5 is cut off, and as shown by the hatched arrow in Fig. 5, the driving force of the engine 2 is transmitted to the generator 4 via the power generation path 54, causing the generator 4 to generate power.

[0072] [3-4. Pseudo Series Mode] In the series mode described above, the switching mechanism 42 is in the second state, and the adjustment path disconnection mechanism 42C is in the disconnected state. This disconnects the generator 4 from the left drive shaft 11L, making it impossible to achieve torque vectoring. Therefore, in the vehicle 1 of this embodiment, when both power generation using the driving force of the engine 2 and torque vectoring are required, the quasi-series mode is implemented.

[0073] The quasi-series mode is a driving mode in which the motor 3 is driven by a portion of the driving force of the engine 2 to generate electricity, while the vehicle 1 travels using the remaining driving force of the engine 2. In other words, the quasi-series mode is a driving mode in which the motor 3 is used as a generator to achieve both torque vectoring using the driving force of the generator 4 and power generation using the power of the engine 2. The quasi-series mode is selected, for example, when the charge level of the battery 7 is not very low (for example, moderate) and when, for example, a passenger requests that the battery 7 be charged.

[0074] In the pseudo series mode, as shown in Fig. 6, the connecting / disconnecting mechanism 41 is engaged and the engine 2 is operating, so that the driving force of the engine 2 is transmitted to the differential mechanism 5 via the first path 52 of the main path 51, as indicated by the dotted arrow in Fig. 6.

[0075] In addition, in the pseudo series mode, the motor 3 is placed in a regenerative (power generating) state. As a result, as shown by the hatched arrows in Fig. 6, a portion of the driving force of the engine 2 transmitted to the differential mechanism 5 is transmitted to the motor 3 via the second path 53 of the main path 51, causing the motor 3 to generate power. In addition, the remaining driving force of the engine 2 transmitted to the differential mechanism 5 is distributed and transmitted by the differential mechanism 5 to each of the left drive shaft 11L and the right drive shaft 11R as a traveling driving force.

[0076] In the quasi-series mode, the switching mechanism 42 is set to the first state. That is, the adjustment path connection / disconnection mechanism 42C is set to the engaged state, and the power generation path connection / disconnection mechanism 42G is set to the disconnected state. Furthermore, by appropriately switching the generator 4 between the power generation state and the regeneration state, torque vectoring is achieved while traveling in the quasi-series mode. In the quasi-series mode, as in the EV mode and parallel mode described above, the driving force of the generator 4 is transmitted to the drive shaft 11 as an adjusted driving force via the adjustment path 55, as shown by the white arrow in FIG. 6, thereby achieving torque vectoring.

[0077] As in the EV mode and the parallel mode, in the pseudo-series mode, when torque vectoring is not required, the generator 4 may be controlled to 0 [N]. Alternatively, when torque vectoring is not required, the switching mechanism 42 may be controlled to be in a neutral state. Alternatively, when torque vectoring is not required, the mode may be switched to the series mode.

[0078] If the charge level of the battery 7 becomes extremely low while the quasi-series mode is selected and torque vectoring is being performed, the mode may be switched to series mode. When switching to series mode while torque vectoring is being performed, it is preferable that the generator 4 be controlled so that the rotation speed difference between the left drive wheel WL and the right drive wheel WR gradually decreases in order to prevent a sudden change in cornering performance.

[0079] [4. Effects] (1) The power transmission device 10 described above is provided with a main path 51, a power generation path 54, and an adjustment path 55. In addition, a power generation path disconnection mechanism 42G is provided on the power generation path 54, and an adjustment path disconnection mechanism 42C is provided on the adjustment path 55.

[0080] In the power transmission device 10 described above, by disengaging the power generation path disconnection mechanism 42G and engaging the adjustment path disconnection mechanism 42C, the driving force of the generator 4 can be transmitted to the drive shaft 11 as an adjusted driving force via the adjustment path 55, which is provided separately from the main path 51. Therefore, torque vectoring can be achieved without adding a new rotating electric machine for torque vectoring, thereby reducing costs and saving space. Furthermore, torque vectoring can stabilize the posture of the vehicle 1 and improve its turning performance (cornering performance).

[0081] Furthermore, in the power transmission device 10 described above, by placing the power generation path connecting / disconnecting mechanism 42G in an engaged state and the adjustment path connecting / disconnecting mechanism 42C in a disconnected state, the generator 4 can also function as a conventional generator that generates electricity using the driving force of the engine 2. This makes it possible for the vehicle 1 to travel while the generator 4 is generating electricity, and the vehicle 1 can be traveled in a variety of travel modes.

[0082] (2) In the power transmission device 10 described above, when neither power generation by the generator 4 nor torque vectoring via the power generation path 54 is required, both the adjustment path disconnection mechanism 42C and the power generation path disconnection mechanism 42G are in a disconnected state. This reduces power consumption by the generator 4 and unnecessary power consumption by the battery 7.

[0083] (3) In the above-described power transmission device 10, the first path 52 and the second path 53 are provided as the main path 51. The first path 52 is provided with the disconnection mechanism 41. By providing the disconnection mechanism 41, it is possible to switch the disconnection state between the engine 2 and the differential mechanism 5 depending on whether or not the driving force needs to be transmitted from the engine 2 to the differential mechanism 5 via the first path 52. Therefore, it is possible to run the vehicle 1 in a wider variety of running modes.

[0084] (4) In the above-described power transmission device 10, when the vehicle 1 runs on the driving force of the motor 3, as in the EV mode, the adjustment path disconnection mechanism 42C is engaged, and the power generation path disconnection mechanism 42G and the disconnection mechanism 41 are disconnected. This enables torque vectoring while the vehicle 1 runs on the driving force of the motor 3, thereby stabilizing the posture of the vehicle 1 and improving cornering performance.

[0085] (5) In the above-described power transmission device 10, when the vehicle 1 runs on the driving force of the engine 2, as in the parallel mode, the adjustment path connecting / disconnecting mechanism 42C and the disconnecting mechanism 41 are engaged, and the power generation path connecting / disconnecting mechanism 42G is disconnected. This allows torque vectoring while the vehicle 1 runs on the driving force of the engine 2, thereby stabilizing the posture of the vehicle 1 and improving cornering performance. In addition, the driving force of the motor 3 can also be used to assist the running of the vehicle 1, ensuring the off-road capabilities of the vehicle 1.

[0086] (6) In the power transmission device 10 described above, when the vehicle 1 runs on the driving force of the motor 3 and requires power generation by the generator 4 via the power generation path 54, as in the series mode, the adjustment path connecting / disconnecting mechanism 42C and the connecting / disconnecting mechanism 41 are disconnected, and the power generation path connecting / disconnecting mechanism 42G is engaged. As a result, for example, when the charge level is extremely low, the motor 3 is driven by the power generated by the generator 4, and the vehicle 1 can run on the driving force of the motor 3.

[0087] (7) In the power transmission device 10 described above, when both power generation using the driving force of the engine 2 and torque vectoring are required, as in the quasi-series mode, the adjustment path connection / disconnection mechanism 42C and the connection / disconnection mechanism 41 are engaged, and the power generation path connection / disconnection mechanism 42G is disengaged. Furthermore, the vehicle 1 travels using the driving force of the engine 2, and the motor 3 generates electricity using a portion of the power of the engine 2. This allows the vehicle 1 to travel while generating electricity using the driving force of the engine 2, and also enables torque vectoring while traveling, thereby stabilizing the posture of the vehicle 1 and improving cornering performance.

[0088] [5. Other] The configurations of the power transmission device 10 and the vehicle 1 described above are examples. The configurations of the main path 51, the power generation path 54, and the adjustment path 55 of the power transmission device 10 described above are examples. For example, the adjustment path 55 may be a path that transmits the driving force of the generator 4 to the right drive shaft 11R. The main path 51 does not need to be provided with the first path 52 and the second path 53 separately. Furthermore, in the power transmission device 10 described above, the number and arrangement of the shafts and gears that form each of the main path 51, the power generation path 54, and the adjustment path 55 are examples.

[0089] Another example is the arrangement of the disconnecting mechanisms provided in each of the first path 52, the power generation path 54, and the adjustment path 55. The power generation path disconnecting mechanism 42G and the adjustment path disconnecting mechanism 42C may be provided separately. For example, the power generation path disconnecting mechanism 42G may be provided on the engine shaft 12, and the adjustment path disconnecting mechanism 42C may be provided on the third countershaft 18. If it is not necessary to connect or disconnect the power transmission from the engine 2 to the differential mechanism 5, the disconnecting mechanism 41 may be omitted. The power transmission device 10 may be provided with a disconnecting mechanism that connects and disconnects the power transmission from the motor 3 to the differential mechanism 5.

[0090] The left drive shaft 11L and the right drive shaft 11R only need to be connected to at least the left axle 6L and the right axle 6R, respectively, and the drive shaft 11 does not have to be connected coaxially with the axle 6. For example, the drive shaft 11 may be disposed at an axial position different from that of the axle 6, and the left drive shaft 11L and the left axle 6L may be connected to the right drive shaft 11R and the right axle 6R, respectively, via a gear train. [Industrial Applicability]

[0091] The present invention is applicable to the power transmission device manufacturing industry, and also to the vehicle manufacturing industry in which the power transmission device is mounted. [Explanation of symbols]

[0092] 1 vehicle 2 engines 3 Motor (Daiichi Electric Machinery) 4. Generator (second rotating electric machine) 5 Differential mechanism 10 Power transmission device 11 Drive shaft 11L left drive shaft 11R Right drive shaft 41 Connection / disconnection mechanism (third connection / disconnection mechanism) 42 Switching mechanism 42C Adjustment path disconnection mechanism (first disconnection mechanism) 42G Power generation path disconnection mechanism (second disconnection mechanism) 51 Main path (main power transmission path) 52 First path (first power transmission path) 53 Second path (second power transmission path) 54 Power generation path (power generation transmission path) 55 Adjustment path (adjustment power transmission path)

Claims

1. A power transmission device for a vehicle equipped with an engine, a first rotating electric machine, a differential mechanism interposed between a left drive shaft and a right drive shaft, and a second rotating electric machine that generates electricity using power from the engine, a main power transmission path that distributes and transmits power of at least one of the engine and the first rotating electric machine to each of the left drive shaft and the right drive shaft via the differential mechanism; a power generation power transmission path that transmits power from the engine to the second rotating electric machine; an adjustment power transmission path that is provided separately from the main power transmission path and transmits power of the second rotating electric machine to the left drive shaft or the right drive shaft; a first connecting / disconnecting mechanism provided on the adjusted power transmission path and configured to connect / disconnect the transmission of power from the second rotating electric machine; a second connection / disconnection mechanism that is provided on the generated power transmission path and that connects / disconnects the transmission of power from the engine to the second rotating electric machine; A power transmission device characterized by:

2. When both the power generation of the second rotating electric machine via the power generation power transmission path and the power transmission of the second rotating electric machine via the adjustment power transmission path are unnecessary, Both the first and second connecting / disconnecting mechanisms are in a disconnected state.

2. The power transmission device according to claim 1, wherein:

3. the main power transmission path is provided separately with a first power transmission path that transmits power from the engine and a second power transmission path that transmits power from the first rotating electric machine, A third connecting / disconnecting mechanism that connects and disconnects the transmission of power from the engine to the differential mechanism is provided on the first power transmission path.

3. The power transmission device according to claim 1 or 2, characterized in that:

4. When the vehicle runs using the power of the first rotating electric machine, the first connecting / disconnecting mechanism is in an engaged state, the second disconnecting mechanism is in a disconnected state, The third connecting / disconnecting mechanism is in a disconnected state.

4. The power transmission device according to claim 3, wherein:

5. When the vehicle runs on the power of the engine, the first connecting / disconnecting mechanism is in an engaged state, the second disconnecting mechanism is in a disconnected state, The third connecting / disconnecting mechanism is brought into an engaged state.

4. The power transmission device according to claim 3, wherein:

6. When the vehicle runs on the power of the first rotating electric machine and requires the second rotating electric machine to generate power via the generated power transmission path, The first disconnecting mechanism is in a disconnected state, the second connecting / disconnecting mechanism is in an engaged state, The third connecting / disconnecting mechanism is in a disconnected state.

4. The power transmission device according to claim 3, wherein:

7. When the vehicle requires both power generation using power of the engine and power transmission of the second rotating electric machine via the adjusted power transmission path, the first connecting / disconnecting mechanism is in an engaged state, the second disconnecting mechanism is in a disconnected state, the third connecting / disconnecting mechanism is in an engaged state, The vehicle runs on the power of the engine, and the first rotating electric machine generates electricity using a portion of the power of the engine.

4. The power transmission device according to claim 3, wherein:

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